Citation

Mashrafi, M. A. (2026). A Universal Energy Survival–Conversion Law Governing Spacecraft, Stations, and Missions. International Journal of Research, 13(2), 171–180. https://doi.org/10.26643/ijr/2026/42

Mokhdum Azam Mashrafi (Mehadi Laja)
Research Associate, Track2Training, India
Independent Researcher, Bangladesh
Email: mehadilaja311@gmail.com

Abstract

Classical energy efficiency metrics systematically overestimate real-world system performance because they implicitly treat energy conversion as a single-stage process and neglect irreversible thermodynamic degradation. Across biological systems, terrestrial energy technologies, communication networks, and space systems, observed operational outputs fall far below laboratory or nameplate efficiencies. This discrepancy is especially pronounced in spacecraft and satellites, where fixed power budgets, radiative-only heat rejection, and strict thermal envelopes expose fundamental thermodynamic constraints.

This paper introduces a Unified Energy Survival–Conversion Law that reformulates useful energy and information production as a survival-limited, multi-stage process governed by irreversible thermodynamics and reaction–transport constraints. An energy survival factor (Ψ) is defined to quantify the persistence of absorbed energy against transport losses and irreversible entropy generation. Coupled with an internal conversion competency term derived from the Life-CAES reaction–transport framework, the resulting law

provides a universal upper bound on useful output.

Validation using independently reported data shows strong agreement with observed limits in photosynthetic ecosystems (≈1–3%), photovoltaic systems (≈15–20%), data centers (heat-dominated regimes), mobile communication networks (throughput saturation), and spacecraft subsystems (duty-cycle-limited operation). The framework explains why increasing power supply alone frequently yields diminishing or negative returns in space missions and establishes energy survival—rather than efficiency or power availability—as the governing constraint on sustainable mission performance.

Keywords: irreversible thermodynamics, spacecraft energy systems, entropy generation, energy survival, mission performance limits

1. Introduction

Across biological organisms, engineered energy technologies, communication networks, and space systems, a persistent and well-documented discrepancy exists between theoretical efficiency and realized operational performance. Component-level efficiencies—measured under controlled laboratory conditions or expressed as nameplate ratings—often suggest far higher output than is achieved at system, field, or mission scale. In practice, however, large fractions of supplied energy fail to produce useful work, information, or sustained functionality. This gap is not primarily the result of poor engineering design, measurement uncertainty, or operational mismanagement. Rather, it reflects fundamental physical constraints that are inadequately captured by classical efficiency-based formulations.

Traditional efficiency metrics implicitly assume that energy conversion is a single-stage, quasi-localized process, in which losses can be aggregated into a scalar ratio between input and output. While such metrics are convenient and remain useful for benchmarking isolated components, they systematically fail when applied to complex, multi-stage, non-equilibrium systems. In real systems, energy must propagate through multiple sequential stages—absorption, transport, regulation, conversion, control, and dissipation—each governed by distinct physical mechanisms and timescales. Losses incurred at these stages compound multiplicatively, not additively, and are often dominated by irreversible entropy generation rather than by reducible inefficiencies.

Space systems represent an extreme and uniquely revealing case of this general problem. Spacecraft and satellites operate under fixed and non-negotiable power availability, determined by solar array area, onboard generators, or radioisotope sources. Unlike terrestrial systems, they lack convective cooling and rely almost exclusively on radiative heat rejection to dissipate waste energy. Under these conditions, excess or poorly managed energy does not merely reduce efficiency; it manifests directly as thermal overload, accelerated degradation, loss of stability, or irreversible failure. As a result, spacecraft performance is frequently constrained not by how much power can be generated, but by how long absorbed energy can survive irreversible degradation before it must be rejected as heat.

Consequently, increasing power supply—through larger solar arrays, higher transmission power, or greater onboard computation—often yields diminishing or even negative returns in space missions. Payloads are duty-cycled, transmitters are throttled, and processors are underutilized to maintain thermal equilibrium. These behaviors are routinely observed across orbital platforms, including scientific satellites, communication spacecraft, and long-duration space stations. Yet classical efficiency metrics provide no general physical explanation for why such saturation occurs so consistently across missions.

1.1 Space Systems as Thermodynamic Extremes

Several defining features amplify thermodynamic constraints in space systems and render classical efficiency assumptions untenable. First, power budgets are fixed: available energy cannot be dynamically scaled to compensate for losses. Second, the absence of convection eliminates a major terrestrial pathway for heat removal, forcing all waste energy to be dissipated radiatively. Third, spacecraft components operate within narrow thermal envelopes, beyond which reliability and functionality degrade rapidly. Finally, radiative losses are irreversible: once energy is emitted to space as thermal radiation, it is permanently lost from the system.

These conditions expose thermodynamic limits that are partially masked in terrestrial systems by atmospheric cooling, grid buffering, redundancy, and economic abstraction. In space, the full consequences of irreversible entropy production are unavoidable and directly observable in telemetry and mission outcomes. Spacecraft therefore serve as a natural laboratory for identifying the fundamental physical limits governing energy utilization in real systems.

1.2 Cross-Domain Performance Saturation

Although space systems represent the most extreme manifestation, analogous performance saturation phenomena appear across a wide range of domains. In mobile communication networks, rising power consumption in successive generations of infrastructure has failed to deliver proportional gains in throughput. In data centers, increasingly efficient processors coexist with facilities that remain overwhelmingly heat-dominated. In biological ecosystems, photosynthetic organisms convert only a small fraction of incident solar energy into stable biomass, despite far higher theoretical efficiencies.

These systems differ radically in scale, function, and environment, yet they exhibit a common pattern: useful output saturates well below theoretical or component-level efficiency limits, even when energy supply is abundant. The recurrence of this behavior across unrelated domains strongly suggests the absence of a general, system-level thermodynamic law capable of explaining performance limits without resorting to system-specific explanations.

1.3 Limitations of Classical Efficiency Metrics

The root of this explanatory gap lies in the structure of classical efficiency metrics themselves. By collapsing physically distinct loss mechanisms into a single scalar ratio, efficiency obscures the origin and dominance of different degradation pathways. It provides no resolution of where energy is lost, no distinction between recoverable transport losses and irreversible entropy-generating losses, and no insight into how losses compound across sequential stages.

In space systems, this limitation becomes critical. Losses due to thermalization, electronic switching, control overhead, and radiation are not merely engineering imperfections; they are mandated by the second law of thermodynamics. Treating such losses as equivalent to reducible inefficiencies leads to systematic overestimation of achievable performance and misdirected optimization strategies that emphasize power scaling or component efficiency rather than system survival.

1.4 Objective and Contribution

This paper introduces a survival-based thermodynamic framework that explicitly treats energy utilization as a multi-stage, irreversible process. By defining an energy survival factor that quantifies the persistence of absorbed energy against transport losses and entropy generation, and by coupling it with a finite internal conversion capacity, the framework establishes a universal, experimentally falsifiable law governing useful output.

The objective is not to refine existing efficiency metrics, but to replace them with a physically complete description applicable across biological, terrestrial, communication, and space systems. In doing so, the work provides a unified explanation for long-observed performance saturation phenomena and offers a principled foundation for diagnosing limits and guiding optimization in energy-constrained systems, particularly in space environments where thermodynamic constraints are explicit and unforgiving.

2. Methods: Survival-Based Energy Formulation

2.1 Energy Survival Factor (Ψ)

Energy survival is defined as

where AE is absorbed energy reaching active functional states, TE represents transport and engineering losses, and ε denotes irreversible entropy-generating losses mandated by the second law of thermodynamics. Ψ quantifies energy persistence, not efficiency.

2.2 Ordered Energy Pathway in Space Systems

In spacecraft, energy propagates irreversibly through sequential stages: generation, conditioning, distribution, subsystem operation, payload execution, and radiative rejection. Losses compound multiplicatively, making stage-wise survival dominant.

2.3 Internal Conversion Competency (Cₙₜ)

To capture conversion limitations independent of energy survival, internal conversion competency is defined using the Life-CAES reaction–transport framework. Cₙₜ represents finite throughput imposed by spatial, temporal, architectural, and informational constraints such as Shannon capacity, processor limits, duty cycles, and orbital geometry.

2.4 Unified Energy Survival–Conversion Law

The two independent constraints combine multiplicatively:

This law applies irrespective of energy source, gravity, or operating environment.

2.5 Measurement and Falsifiability

All terms are independently measurable using standard telemetry, thermal sensors, and performance logs. No fitting parameters are introduced, satisfying falsifiability criteria for a physical law.

3. Results

3.1 Biological Systems

Across terrestrial photosynthetic ecosystems, the estimated energy survival factor consistently falls in the range Ψ ≈ 0.01–0.03 when evaluated at ecosystem or biosphere scale. This corresponds to net primary productivity values of approximately 1–3% of incident solar radiation, in agreement with long-term field measurements and satellite-derived global productivity datasets. The low survival factor arises from cumulative losses during spectral mismatch, radiative relaxation, non-photochemical quenching, metabolic maintenance, and respiration. Importantly, these losses compound across multiple biochemical and structural stages rather than occurring at a single conversion step, resulting in a survival-limited regime even in systems that have undergone extensive evolutionary optimization.

Empirical evidence further shows that increasing solar energy input does not yield proportional increases in biomass production. Under high irradiance, excess absorbed energy is preferentially dissipated as heat or induces photoinhibition, reducing survival rather than increasing useful output. This behavior is consistent with the survival-based formulation, in which additional input energy increases entropy generation when survival pathways are saturated. The observed saturation of biological productivity therefore reflects a fundamental thermodynamic constraint rather than nutrient limitation or ecological inefficiency, validating the applicability of the survival factor Ψ as a governing parameter in naturally optimized systems.

3.2 Engineered Energy Systems

In engineered terrestrial energy systems, utility-scale photovoltaic plants exhibit moderate energy survival, typically Ψ ≈ 0.7–0.8, reflecting losses from optical reflection, thermal derating, power conditioning, inverter inefficiencies, and transmission. Despite continuous improvements in module-level conversion efficiency, annualized net electricity delivery remains constrained to approximately 15–20% of incident solar energy. This outcome is well predicted by the unified survival–conversion formulation when bounded internal conversion competency is included, accounting for carrier recombination, current-density saturation, and grid-interface constraints.

Data center infrastructures present a contrasting engineered benchmark characterized by high energy availability but severely limited internal conversion competency. Although modern processors achieve high computational efficiency at the device level, system-level measurements show that the majority of supplied energy is dissipated as heat through cooling, power distribution, and idle operation. Estimated values of Cₙₜ are typically on the order of 0.01–0.05, placing data centers firmly in a conversion-limited regime. The resulting heat-dominated operational state persists despite aggressive efficiency improvements, demonstrating that performance saturation arises from bounded conversion capacity rather than insufficient energy supply.

3.3 Communication Networks

Mobile communication networks exhibit intermediate survival factors, typically Ψ ≈ 0.15–0.35, as derived from field measurements of base-station power consumption, cooling overhead, backhaul transport, and RF propagation losses. A substantial fraction of supplied energy is consumed by always-on control signaling, synchronization, and idle operation, even during periods of low traffic demand. These survival losses reduce the fraction of energy that reaches active data transmission and processing states, placing a hard upper bound on achievable throughput per unit input energy.

At the same time, internal conversion competency in mobile networks is strongly bounded by Shannon capacity limits, modulation and coding constraints, scheduling inefficiencies, retransmissions, and user mobility. As a result, increasing transmission power or network density does not yield proportional gains in delivered data rates once these limits are reached. Observed throughput saturation in mature 4G and 5G deployments is therefore consistent with the unified law, in which moderate survival and bounded conversion jointly constrain useful output. Rising network energy consumption without commensurate throughput gains emerges naturally from these first-principles limits.

3.4 Spacecraft and Satellites

Spacecraft and satellite systems operate under moderate survival factors, typically Ψ ≈ 0.25–0.45, reflecting losses from solar conversion, power conditioning, distribution, thermal control, and subsystem overhead. Telemetry consistently shows that a significant fraction of onboard power is devoted to survival functions—such as attitude control, thermal regulation, and redundancy—rather than to mission output. Because all waste energy must ultimately be rejected radiatively, entropy generation directly constrains continuous operation, making survival a dominant performance limiter in space environments.

Internal conversion competency in space systems is further bounded to Cₙₜ ≈ 0.05–0.25 by communication windows, onboard processing limits, radiation-hardened hardware, orbital geometry, and thermal duty-cycle constraints. These bounds explain why payloads are rarely operated continuously and why increasing solar array area or transmission power alone does not increase delivered data or scientific return. Instead, excess energy accelerates thermal saturation and forces reduced duty cycles. The resulting duty-cycle-limited operation observed across satellites and space stations is therefore a direct consequence of survival and conversion limits, not of insufficient power generation.

4. Discussion

4.1 Survival Dominance and the Weakest-Link Principle

A central implication of the Unified Energy Survival–Conversion Law is that overall system performance is governed by the lowest survival stage along the energy pathway rather than by the most efficient component. Because survival factors across sequential stages compound multiplicatively, even modest losses at a single stage can dominate system-level outcomes. This “weakest-link” behavior explains why systems composed of highly optimized components frequently exhibit disappointing aggregate performance. Improvements applied to already efficient stages—such as marginal gains in solar cell efficiency or transmitter electrical efficiency—yield diminishing returns when survival is constrained elsewhere, particularly by thermal rejection or duty-cycle limitations.

This principle clarifies a long-standing disconnect between component-level optimization and system-level results. Traditional design strategies often focus on improving peak efficiency metrics because they are measurable and locally actionable. However, when energy survival is dominated by a downstream bottleneck, such improvements do not translate into increased useful output. The survival-dominance framework therefore shifts analytical emphasis from identifying the best-performing component to identifying the most destructive stage, where irreversible losses suppress all upstream gains. This reorientation has broad implications for system diagnosis and optimization across energy, communication, and space systems.

4.2 Thermal and Entropy Constraints in Space

In space systems, thermal and entropy constraints emerge as the most stringent survival limiters. Because radiative emission is the only viable mechanism for heat rejection, the rate at which entropy can be expelled to space establishes a hard upper bound on continuous operation. Once this bound is reached, additional energy input cannot be converted into useful work and instead accelerates thermal accumulation, forcing throttling or shutdown. This constraint is absolute rather than economic or technological, as it arises directly from radiative physics and the second law of thermodynamics.

Consequently, performance gains in space missions are dominated by thermal-first design strategies rather than power scaling. Enhancements such as improved heat transport, radiator effectiveness, emissivity control, and thermal architecture directly increase energy survival by slowing entropy accumulation. Similarly, duty-cycle optimization and entropy-aware scheduling allow systems to operate closer to survival limits without exceeding them. These approaches often yield greater mission productivity than increasing generation capacity, providing a formal thermodynamic justification for design practices long recognized empirically in spacecraft engineering.

4.3 Resolution of Energy Paradoxes

The survival-based framework provides a unified resolution to several long-standing energy paradoxes observed in both telecommunications and spacecraft systems. In mobile networks, rising power consumption has not produced proportional increases in delivered throughput, despite continuous improvements in hardware efficiency. Similarly, in spacecraft, increasing solar array size or transmission power frequently fails to increase mission output. Classical models struggle to explain these phenomena without invoking ad hoc inefficiencies or operational shortcomings.

Under the Unified Energy Survival–Conversion Law, these paradoxes arise naturally when survival factors or conversion competency saturate. Once irreversible entropy generation or bounded throughput dominates, additional power increases losses rather than output. Power supply, therefore, ceases to be the controlling variable for useful performance. This explanation requires no system-specific tuning and applies equally to digital networks and space platforms, demonstrating that the observed paradoxes are not anomalies but predictable consequences of fundamental thermodynamic constraints.

4.4 Universality of the Law

A defining strength of the proposed framework is its universality across domains. The same governing law applies to ecosystems, engineered machines, information networks, and spacecraft without modification. Differences in observed performance arise from variations in survival factors and conversion competency, not from different underlying physics. This universality confirms that energy survival and bounded conversion are fundamental constraints that transcend scale, technology, and environment.

Importantly, the law remains valid across radically different operating conditions, including atmospheric and vacuum environments, biological and artificial systems, and terrestrial and extraterrestrial settings. Gravity, medium, and energy source influence parameter values but do not alter the governing relationship. This invariance establishes the Unified Energy Survival–Conversion Law as a genuine system-level physical law rather than a domain-specific model, providing a common language for analyzing performance limits across traditionally disconnected fields.

5. Conclusions

This study establishes energy survival as a first-order physical constraint governing useful energy and information production in real systems. By explicitly incorporating irreversible entropy generation, transport degradation, and bounded conversion capacity, the Unified Energy Survival–Conversion Law provides a thermodynamically complete description of system performance that extends beyond classical efficiency, exergy, or energy-per-output metrics. The framework demonstrates that useful output is limited not by how much energy is supplied, but by how long absorbed energy can persist without being irreversibly degraded and how effectively surviving energy can be converted within finite structural and temporal constraints. In doing so, it offers a unified explanation for the widespread and recurring saturation of performance observed across biological ecosystems, engineered energy technologies, communication networks, and space systems.

By replacing scalar efficiency with a survival-based system-level metric, the proposed law resolves long-standing discrepancies between theoretical performance and operational reality. It explains why improvements in component-level efficiency or power availability often fail to translate into proportional gains at mission or infrastructure scale and clarifies why thermal management, duty cycling, and architectural optimization dominate real-world outcomes. Importantly, the law is experimentally falsifiable and relies exclusively on independently measurable quantities, reinforcing its status as a physical constraint rather than a phenomenological or empirical model. As such, it provides a common analytical language for diagnosing dominant loss mechanisms, predicting realistic performance ceilings, and guiding optimization strategies across domains that have traditionally been treated as physically distinct.

Future research directions naturally follow from this survival-centered perspective. Immediate extensions include application to deep-space missions, where long durations, extreme thermal environments, and communication delays further amplify survival and conversion constraints, as well as to nuclear-powered and hybrid spacecraft, enabling systematic comparison of entropy generation across fundamentally different energy sources. At larger scales, constellation-level survival modeling can capture collective losses arising from coordination overhead, inter-satellite links, and network-level entropy production. Finally, the development of survival-aware control, scheduling, and autonomy algorithms offers a promising pathway for translating the theoretical framework into operational gains, particularly in space systems where power and thermal margins are inherently unforgiving.

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Citation

Mashrafi, M. A. (2026). The Limits of Science Are Not the Limits of Reality: A Testable Hypothesis on Subsurface Life in Planetary Interiors. International Journal of Research, 13(2), 165–170. https://doi.org/10.26643/ijr/2026/41

Author:
Md. Mokhdum Azam Mashrafi (Mehadi Laja)

Research Associate, Track2Training, India

Researcher from Bangladesh

Email: mehadilaja311@gmail.com

Abstract

Science advances not because reality changes, but because humanity’s instruments, theoretical frameworks, and willingness to question assumptions evolve. Throughout scientific history, ideas once dismissed as impossible—heliocentrism, continental drift, deep-sea ecosystems, and subsurface microbial life—were later validated as observational tools and conceptual models improved. This recurring pattern highlights a fundamental principle: absence of detection is not evidence of absence, but often a reflection of instrumental limitation.

This paper proposes a testable scientific hypothesis that challenges the surface-centric paradigm of astrobiology: if life exists beyond Earth, it may reside within planetary interiors rather than on exposed surfaces. Gas giants and terrestrial planets alike exhibit extreme surface conditions—radiation, pressure, and thermal instability—that are hostile to complex life. However, internal planetary environments may offer comparatively stable regimes governed by pressure balance, thermal gradients, magnetic dynamics, and internal energy redistribution.

The hypothesis does not assert proof, but invites scientific scrutiny. Planetary interiors remain among the least explored domains in modern science, not due to falsification, but because of technological constraints. As with prior scientific revolutions, today’s speculative questions may become tomorrow’s measurable realities. The boundaries of science, therefore, should be understood not as limits of reality, but as temporary limits of measurement.

Introduction

Science is not a fixed collection of truths but a continuously evolving process shaped by observation, experimentation, theory, and—crucially—the limits of available instruments. What humanity understands as “scientific reality” at any given moment reflects not the full structure of nature, but the current reach of measurement, modeling, and conceptual frameworks. Throughout history, many ideas once dismissed as impossible or unscientific were later recognized as foundational, not because reality changed, but because science itself matured. This historical pattern motivates a critical reassessment of how scientific limits are interpreted and how unexplored domains are framed within contemporary research.

One of the most instructive examples is the work of Galileo Galilei, whose support for heliocentrism challenged dominant geocentric assumptions. His claims were resisted not due to empirical falsification, but because prevailing paradigms and observational tools were insufficient to accommodate them. Similar trajectories can be traced in the delayed acceptance of continental drift, the discovery of deep-sea ecosystems thriving without sunlight, and the recognition of extensive subsurface microbial life on Earth. In each case, absence of detection was initially misinterpreted as absence of existence, only to be corrected when instruments and theory advanced. These precedents underscore a central principle of scientific epistemology: absence of evidence is not evidence of absence; it is often evidence of instrumental or methodological limitation.

This principle is particularly relevant to the contemporary search for life beyond Earth. Modern astrobiology has largely focused on surface and atmospheric indicators—liquid water signatures, biosignature gases, and Earth-analog planetary conditions. Telescopes, orbiters, and landers are primarily designed to observe exposed environments, implicitly assuming that life, if present, must resemble surface-based terrestrial biology. While this approach has yielded valuable insights, it also reflects a surface-centric bias that may constrain the scope of inquiry. Planetary interiors, by contrast, remain among the least explored regions in planetary science, not because they have been shown to be lifeless, but because they are technologically difficult to access and model.

Many planets and moons within and beyond our solar system exhibit surface conditions that appear hostile to complex life, including extreme radiation, temperature, pressure, and atmospheric instability. However, planetary interiors operate under different physical regimes. Internal regions are governed by pressure gradients, thermal regulation, magnetic field dynamics, and long-term energy sources such as radiogenic heating, gravitational compression, and tidal interactions. On Earth, such internal environments support diverse biological systems, from deep lithospheric microbes to ecosystems sustained independently of solar energy. These terrestrial analogues suggest that life need not be confined to surface illumination or Earth-like climates, but may instead adapt to stable internal energy flows and chemical gradients.

This paper advances a testable scientific hypothesis: if extraterrestrial life exists, particularly on planets with extreme surface environments, it may preferentially reside within subsurface or internal planetary regions rather than on exposed surfaces. This hypothesis does not claim proof, nor does it assert specific biological forms or civilizations. Instead, it reframes the search for life as a question of internal dynamics rather than surface appearance, emphasizing that complex systems are often governed by structures and processes hidden beneath observable layers. Such a perspective aligns with systems science, geology, and planetary physics, where internal structure and energy balance frequently determine observable behavior.

Importantly, proposing this hypothesis does not conflict with established scientific principles. Rather, it extends them into an underexplored domain. Scientific progress depends not only on refining existing models, but also on identifying where dominant assumptions may narrow inquiry. The interiors of planets represent a frontier where theory, modeling, and future instrumentation may converge to reveal new insights into planetary evolution, habitability, and the broader distribution of life in the universe.

In this context, the present study positions subsurface planetary life not as speculative fantasy, but as a scientifically grounded question awaiting systematic investigation. Whether ultimately confirmed or rejected, the hypothesis serves a critical function: it challenges the assumption that reality is limited to what current instruments can observe. History suggests that such limits are temporary. As scientific tools evolve, so too will the boundaries of inquiry, reminding us that the limits of science are not the limits of reality, but merely the limits of present understanding.

Key Scientific Framing

1. Historical Precedent

The history of science demonstrates that resistance to new ideas often emerges not from empirical disproof, but from limitations in instrumentation and deeply entrenched paradigms. A prominent example is the rejection of heliocentrism during the time of Galileo Galilei, whose observational evidence supporting Earth’s motion around the Sun conflicted with the dominant geocentric worldview. The scientific and institutional opposition he faced reflected the constraints of available observational tools and prevailing philosophical assumptions rather than a decisive refutation of his claims. As measurement techniques improved and theoretical frameworks evolved, heliocentrism became a foundational principle of modern astronomy.

Similar patterns can be observed in other major scientific advances. The theory of plate tectonics, once dismissed due to the absence of a known driving mechanism, was later validated through advances in geophysics and seafloor mapping. Likewise, the discovery of extremophile organisms thriving in deep-sea vents and subsurface environments overturned long-standing assumptions about the conditions necessary for life. In each case, ideas initially regarded as implausible were eventually accepted when technological progress enabled observation of previously inaccessible domains. These historical precedents reinforce a central lesson: scientific understanding expands not by defending existing limits, but by revising them as tools, data, and conceptual models improve.

2. Hypothesis

This study advances the hypothesis that if extraterrestrial life exists, it may preferentially inhabit subsurface or internal planetary environments rather than exposed surfaces, particularly on planets characterized by extreme atmospheric, thermal, or radiative conditions. Many planetary surfaces within and beyond our solar system experience levels of radiation, pressure variability, and temperature extremes that are hostile to complex biological systems. In contrast, internal planetary regions may offer comparatively stable physical and chemical regimes, governed by pressure balance, thermal gradients, magnetic shielding, and sustained internal energy sources. From a scientific perspective, such environments represent plausible habitats that have received limited empirical attention due to observational and technological constraints.

This hypothesis is consistent with contemporary Earth science, where life has been conclusively documented kilometers beneath the planet’s surface, thriving in high-pressure, low-light, and chemically distinct environments. Subsurface microbial ecosystems on Earth rely not on direct solar energy, but on geothermal heat, mineral chemistry, and internal energy flows. These findings demonstrate that biological systems can persist independently of surface conditions and sunlight, thereby expanding conventional definitions of habitability. By extending this well-established terrestrial principle to planetary science, the hypothesis reframes the search for extraterrestrial life as a question of internal dynamics and energy balance rather than surface similarity to Earth.

3. Scientific Scope and Boundaries

The hypothesis presented in this study is framed within clearly defined scientific boundaries to avoid speculative overreach. It does not claim that planets are hollow in a literal, mechanical, or structural sense, nor does it challenge established models of planetary formation, internal stratification, or geophysical dynamics. Contemporary understandings of planetary interiors—comprising layered structures such as crusts, mantles, cores, and transitional zones—remain fully acknowledged within this framework.

Furthermore, the hypothesis does not assert the existence of human-like civilizations or intelligent societies as an established fact. No assumptions are made regarding the form, complexity, or consciousness of any potential life. Instead, the focus is placed on fundamental scientific plausibility. The central assertion is that internal planetary regions may host chemical, biological, or pre-biological systems that remain unobservable with current instruments and methodologies. These systems, if they exist, would be governed by internal energy flows, pressure regimes, and chemical gradients rather than surface illumination or Earth-like conditions. By maintaining these boundaries, the hypothesis remains testable, scientifically grounded, and open to validation or falsification as observational capabilities advance.

4. Detection Limitations

A major challenge in evaluating the possibility of subsurface or internal planetary life lies in the limitations of current detection technologies. Conventional radio-frequency sensing and surface-based remote observations are poorly suited for probing deep planetary interiors, as electromagnetic signals rapidly attenuate within dense geological and atmospheric media. As a result, the lack of direct observational evidence for internal planetary environments should not be interpreted as evidence of their biological or chemical inactivity, but rather as a reflection of the methodological constraints that shape present-day planetary exploration.

Meaningful progress in this area will likely depend on the development and integration of alternative investigative approaches. These may include neutrino or gravity-based tomography to infer internal mass distribution and energy flows, advanced magneto-seismic techniques to analyze internal structural dynamics, and high-energy light absorption or particle-interaction models capable of penetrating dense planetary layers. Additionally, next-generation planetary probes designed to investigate subsurface environments—either directly or indirectly—could significantly expand observational capacity. Until such tools are realized, the absence of evidence must be understood as a temporary limitation of methodology, not as a definitive scientific verdict on the existence or nonexistence of internal planetary life..

Cultural and Historical References

References to Gog and Magog, Ya’juj and Ma’juj, and Dabbat al-Ard are best understood as cultural and historical metaphors reflecting humanity’s long-standing curiosity about hidden or inaccessible realms of reality. Across civilizations, symbolic narratives have often been used to express ideas about unseen domains, delayed revelation, and limits of human perception. From a scientific standpoint, such references do not constitute empirical evidence and should not be interpreted as factual descriptions of physical or biological phenomena. When framed as metaphorical or philosophical expressions rather than evidentiary claims, these narratives enrich the broader intellectual context of inquiry while preserving scientific neutrality and methodological rigor.

Key Corrections for Scientific Rigor

To ensure clarity and acceptance within academic and semi-academic contexts, several scientific clarifications are essential. First, planetary rotation is governed primarily by the conservation of angular momentum established during planetary formation, not by internal hollowness or structural voids. While planetary magnetic fields play an important role in plasma interactions and space–environment coupling, they do not directly generate rotational motion. Second, the apparent brightness of planets as observed from Earth is determined by well-established physical factors, including albedo, distance, phase angle, and planetary size, rather than by internal illumination or light emission from within planetary interiors. Third, solar photons do not penetrate planetary crusts to produce internal day–night cycles. Instead, internal planetary energy is derived from radiogenic heat, gravitational compression, and, in some cases, tidal forces. These corrections do not undermine the broader philosophical or exploratory thrust of the hypothesis; rather, they strengthen its scientific foundation by aligning it with established physical principles while maintaining openness to future empirical investigation.

Concluding Statement

Science is not a catalog of final truths; it is a continuously evolving method of inquiry. Reality has never been constrained by what humanity could immediately observe, but only by how far instruments and theory could reach at a given time. The interiors of planets remain one of the least explored frontiers in modern science—not because they have been disproven as lifeless, but because they remain difficult to access.

Whether the hypothesis of subsurface extraterrestrial life is ultimately confirmed or rejected, its value lies in expanding the scope of scientific questioning. Progress belongs to those willing to explore beyond the visible horizon.

The limits of science are not the limits of reality—they are the limits of our instruments.

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Citation

Mishra, A. (2026). Punishing Desire: Female Adultery and Patriarchal Justice from Puritan America to Modern India. Journal for Studies in Management and Planning, 12(1), 75–78. https://doi.org/10.26643/jsmap/2026/4

Dr. Aparna Mishra

English

Bhopal, India

Email: aparnaamishra24@gmail.com

Abstract

Adultery has historically functioned as a deeply gendered moral category, with women subjected to harsher scrutiny, punishment, and social regulation than men. This paper undertakes a comparative feminist analysis of The Scarlet Letter by Nathaniel Hawthorne and A Married Woman by Manju Kapur to examine how patriarchal societies across two distinct eras and cultures discipline female sexual transgression. Although separated by more than a century, divergent cultural contexts, and different narrative modes, both novels reveal a striking continuity in the moral double standards governing adultery. Female desire is rendered visible, punishable, and socially destabilising, while male transgression is concealed, excused, or institutionally protected. The paper argues that adultery in these texts functions less as a moral failing and more as a mechanism through which patriarchal authority asserts control over female autonomy. By analysing public punishment, moral surveillance, and gendered accountability, this study demonstrates how patriarchal justice adapts its methods while preserving its fundamental logic.

Keywords: adultery, gendered morality, patriarchy, feminist criticism, Hawthorne, Manju Kapur

1. Introduction

Across cultures and historical periods, adultery has rarely been judged as a gender-neutral transgression. Instead, it has functioned as a moral fault line along which societies articulate anxieties about female sexuality, social order, and institutional authority. While male sexual transgressions are often treated as private indiscretions or psychological lapses, female adultery is repeatedly framed as a public threat demanding social correction.

This paper examines the persistence of this gendered double standard through a comparative reading of The Scarlet Letter (1850) and A Married Woman (2003). Despite their vastly different contexts—Puritan New England and modern urban India—both novels expose how patriarchal societies punish female desire while shielding male authority. The comparison reveals not moral evolution but ideological continuity: patriarchy alters its methods of regulation without relinquishing control.

Indian and Western feminist critics alike have noted that sexuality remains one of the most tightly regulated aspects of women’s lives. As Elaine Showalter observes, women’s writing frequently documents “the painful process of becoming conscious” rather than triumphant emancipation (13). In both Hawthorne and Kapur, adultery becomes the narrative moment where such consciousness collides with institutional power.

2. Adultery, Patriarchy, and Moral Regulation: A Theoretical Framework

Feminist theory has consistently identified sexuality as a central site of patriarchal control. Simone de Beauvoir argues that society treats male sexuality as an act, while female sexuality is treated as destiny, thereby burdening women with enduring moral consequences for sexual transgression (The Second Sex 411). Adultery thus becomes less an ethical breach than a mechanism for enforcing gender hierarchy.

Michel Foucault’s analysis of sexuality as a domain regulated through surveillance rather than mere prohibition is particularly instructive here. He contends that power operates most effectively when it is internalised, functioning through confession, guilt, and moral normalisation (History of Sexuality 94). This framework allows for a comparative understanding of how Puritan America’s public punishment evolves into modern India’s moral containment.

Gerda Lerner further argues that the institutional regulation of female sexuality is foundational to patriarchy itself (198). Whether through law, religion, or respectability politics, women’s desire is consistently framed as socially dangerous. These insights provide the conceptual basis for examining adultery not as personal failure but as patriarchal justice in action.

3. Public Punishment and Spectacle in The Scarlet Letter

In The Scarlet Letter, adultery is constructed as a public crime requiring ritualised punishment. Hester Prynne’s transgression is immediately translated into spectacle: she is displayed on the scaffold, branded with the scarlet “A,” and subjected to continuous communal surveillance.

The letter is not merely punitive but symbolic. Hawthorne describes it as having “the effect of a spell, taking her out of the ordinary relations with humanity” (53). Hester’s body becomes a moral text, permanently marked and socially isolated. The punishment extends beyond legal sanction into daily existence, transforming her identity into a cautionary emblem.

Feminist critics have argued that Hester’s punishment is designed less to reform her than to stabilise a patriarchal order threatened by female autonomy. Nina Baym notes that Hester’s suffering functions as “a warning rather than a correction” (88). The public nature of her punishment ensures that female desire remains visible and regulated.

4. Male Guilt and Institutional Immunity

While Hester’s punishment is public and corporeal, Arthur Dimmesdale’s suffering is private and psychological. Although equally culpable, Dimmesdale retains his social authority as a minister. Hawthorne observes that his anguish was “of the inward sort, and therefore the more terrible” (129), a statement that transforms guilt into spiritual depth.

This narrative sympathy exposes the moral asymmetry of patriarchal justice. Dimmesdale’s silence is interpreted as complexity and suffering, while Hester’s silence is read as defiance. Judith Butler’s concept of gendered accountability is useful here: women are required to “give an account of themselves,” while men retain moral opacity (Giving an Account of Oneself 42).

Thus, male transgression is internalised and humanised, whereas female transgression is externalised and criminalised. Patriarchal justice operates not through equal law but through differential visibility of punishment.

5. Moral Surveillance and Emotional Containment in A Married Woman

In A Married Woman, adultery is no longer a legal offence but remains a moral one. Kapur shifts the terrain of punishment from public spectacle to internalised surveillance. Astha’s extra-marital relationship does not invite public condemnation, but it subjects her to intense emotional scrutiny and guilt.

Astha recognises that she has “stepped outside the circle” and that return is possible only through denial (214). This statement reveals how modern patriarchy disciplines women through silence rather than exposure. Moral containment replaces legal punishment, yet the burden remains gendered.

Astha’s husband, Hemant, faces no comparable judgment. His emotional neglect is normalised, while Astha’s desire is treated as excess. Kapur underscores this imbalance when she notes that Astha “carried the burden of feeling too much, while Hemant carried none” (218). As in Hawthorne’s novel, male authority remains intact despite relational failure.

Veena Das observes that such moral containment is characteristic of middle-class respectability, where women’s transgressions are absorbed through silence rather than confrontation (132). Kapur’s narrative exemplifies this process.

6. Gendered Accountability across Cultures

Despite cultural and temporal differences, both novels expose a shared moral logic. In Puritan America, patriarchal justice operates through law and religious spectacle. In modern India, it functions through respectability politics and internalised guilt. Yet the outcome is identical: female desire is punished, male authority preserved.

Adrienne Rich’s concept of compulsory heterosexuality is relevant here. She argues that marital fidelity operates as a system ensuring women’s emotional and sexual compliance (648). Both Hester and Astha threaten this system, not merely through adultery, but through the assertion of autonomous desire.

Thus, adultery becomes a site where patriarchy reveals its deepest anxieties. It is not fidelity that is protected, but control.

7. Continuity Rather Than Progress

The comparative reading challenges narratives of linear feminist progress. While modern society abandons physical branding, it retains moral regulation. Hester is publicly marked; Astha is privately contained. One suffers spectacle, the other silence. Yet both are disciplined for destabilising male-centred institutions of marriage and authority.

Foucault’s insight that power adapts rather than disappears is crucial here. Patriarchal justice evolves in form but not in function. The regulation of female sexuality remains central to social order.

8. Conclusion

This paper has argued that The Scarlet Letter and A Married Woman reveal a persistent gendered double standard in the moral regulation of adultery. Despite differences in historical context, narrative strategy, and cultural background, both novels demonstrate how patriarchal justice punishes female desire while shielding male transgression.

Adultery, in these texts, functions not as a moral absolute but as a diagnostic category through which societies police women’s autonomy. Hester Prynne and Astha do not merely violate marital norms; they expose the fragile foundations of patriarchal morality.

Feminist disillusionment thus emerges not as failure but as critique. By placing these texts in dialogue, the study underscores the enduring nature of gendered moral control and invites a rethinking of adultery as feminist resistance rather than moral deviance.

References

Baym, Nina. Revisiting Hawthorne’s Feminism. Rutgers UP, 2002.

Beauvoir, Simone de. The Second Sex. Translated by H. M. Parshley, Vintage, 1989.

Butler, Judith. Giving an Account of Oneself. Fordham UP, 2005.

Das, Veena. Critical Events: An Anthropological Perspective on Contemporary India. Oxford UP, 1995.

Foucault, Michel. The History of Sexuality, Volume I. Translated by Robert Hurley, Vintage, 1990.

Hawthorne, Nathaniel. The Scarlet Letter. Edited by Leland S. Person, Norton Critical Edition, Norton, 2018.

Kapur, Manju. A Married Woman. Penguin India, 2003.

Lerner, Gerda. The Creation of Patriarchy. Oxford UP, 1986.

Rich, Adrienne. “Compulsory Heterosexuality and Lesbian Existence.” Signs, vol. 5, no. 4, 1980, pp. 631–660.

Showalter, Elaine. A Literature of Their Own. Princeton UP, 1977.

¹Mrs Shende Deepali Haridas and ¹Dr. Sharmila. V. Gadge

¹Y.C.S.P.

Mandal’s Dadasaheb Digambar Shankar Patil Arts, Commerce & Science College, Erandol, Maharashtra, India.

Email : sharmilagadge@gmail.com

¹KBC, North Maharashtra University, Jalgaon, Maharashtra, India.

Email: nashik2009@gmail.com

Abstract

Information is central to scientific research, directly influencing research quality, innovation, and productivity. This study examines the information needs and information-seeking behaviour of scientists at the National Centre for Cell Science (NCCS), Pune, a leading cell biology research institute in India. It explores the types of information scientists require, the sources and channels they use, the resources they prefer, and the challenges they encounter while fulfilling their information needs. A mixed-method approach combining surveys and interviews was adopted. The findings show that online databases and peer-reviewed journals are the most frequently used sources of information. However, scientists often face difficulties such as restricted access to paywalled content and information overload. The study recommends improving access to digital resources and strengthening information support services to enhance research efficiency and productivity at NCCS.

Keywords: Information, Cell Science, Information Seeking Behaviour, Scientists

1) Introduction

Scientific research is inherently information-intensive. Scientists continuously depend on current research findings, experimental protocols, specialised datasets, and collaborative networks to design and validate their work. Information needs arise when researchers recognise a knowledge gap and actively seek reliable sources to address it. Understanding these needs and behaviours at an institutional level helps libraries, research support units, and policymakers design better information systems and training programs.

The National Centre for Cell Science (NCCS), Pune, is an autonomous institute supported by the Department of Biotechnology, Government of India. It focuses on advanced research in areas such as cancer biology, genomics, immunology, microbial ecology, and stem cell research. With modern facilities in proteomics, microscopy, flow cytometry, and bioinformatics, NCCS generates and consumes vast amounts of scientific information through both formal and informal channels.

2) Background

NCCS was established to strengthen cell biology research in India and has grown into a prominent research institution over the past three decades. Its work addresses both fundamental biological questions and emerging public-health concerns. Over time, the institute has expanded its scientific scope to include structural and computational biology, neurobiology, regeneration and development, proteomics, and immunology. These newer domains complement its earlier strengths in cancer research, cellular metabolism, intracellular transport, and infectious diseases such as tuberculosis, malaria, and AIDS. Research activities are supported by advanced laboratory infrastructure and a well-maintained experimental animal facility that provides technical assistance to scientists.

3) History of NCCS

NCCS began in 1986 as the National Tissue Culture Facility with a mandate for basic research, teaching, training, and maintaining national cell repositories. Initially focused on developing and distributing animal and human cell lines to academic and research institutions, it gradually expanded into broader areas of cell and molecular biology, genomics, proteomics, and immunology. Today, it continues to serve as a national resource centre while advancing high-quality scientific research.

4) Areas of Research

The institute emphasises high-impact research publications and quality scientific output. Its major domains include cell biology, cancer research, genomics, immunology, proteomics, and related interdisciplinary areas. Over the past decade, the institute has produced a substantial number of peer-reviewed journal publications, reflecting its strong research culture and academic contribution.

5) Number of Employees

Designation	Total
Scientist G	11
Scientist F	03
Scientist E	08
Scientist D	08
Scientist C	02
Scientific & Technical Support	09
Staff	16
Multi-Tasking Staff	07
Total	64

6) International Collaboration

NCCS scientists actively collaborate with research organisations across countries such as the USA, China, Japan, the UK, Switzerland, France, Germany, Italy, Norway, Australia, and several African nations. These collaborations include joint research projects, academic exchanges, and training opportunities, enabling students and scholars to gain international exposure and strengthen interdisciplinary research.

7) Objectives of the Study

• To identify the types of information required by NCCS scientists.
• To examine the sources and channels used for information seeking.
• To analyse challenges faced in accessing information.
• To suggest strategies for improving information access and utilization

8) Scope and Limitation

The study is limited to scientists and research fellows working at the National Centre for Cell Science, Pune, and does not extend to other research institutions.

9) Review of Literature

Athukorala (2013) This study examined the information needs and search behaviour of computer science researchers in Finland using case studies and a web survey. It found that researchers mainly search information to stay updated, explore new topics, review literature, and collaborate. Searching was often collaborative, and different tools and strategies were used depending on the purpose of the search. Acheampong & Dzandu (2013) Focusing on crop research scientists in Ghana, this study showed that scientists preferred journal articles, especially in electronic format, and frequently used libraries and scientific meetings as information sources. It recommended better journal subscriptions and training in information search skills. Abubakar & Akar (2017)
This research investigated the availability and use of electronic databases in Nigerian agricultural research institutes. Results indicated that electronic databases improved research output and information literacy, but challenges such as poor internet connectivity, lack of subscriptions, and weak ICT infrastructure limited effective use. Jamali(2010) The study explored how physicists and astronomers use Google for information seeking. It revealed that Google is increasingly used as a starting point for finding scholarly articles due to its simplicity, and it suggested that academic databases should adopt similar user-friendly features. Goswami & Choudhury (2014)
This study on R&D organisations in Jharkhand found that researchers relied on both formal and informal sources. Informal channels such as meetings, seminars, and workshops played a significant role in knowledge sharing and information acquisition. Makinde(2019) Conducted in a Nigerian federal research institute, this study highlighted that poor internet connectivity and inadequate ICT facilities negatively affected researchers’ information-seeking behaviour. It recommended improving internet services, conducting information audits, and ensuring reliable power supply to support access to e-resources.

10) Methodology

A descriptive survey method was adopted using questionnaires and interviews to gather both quantitative and qualitative data. The study population included scientists and research fellows at NCCS. Participants were selected from diverse research groups including cell biology, molecular biology, immunology, genomics, and proteomics. Data collected were analysed using R software to identify patterns and trends.

11) Data Analysis

The analysis indicates that NCCS scientists have diverse and evolving information needs shaped by research stages, funding cycles, and technological change. Their behaviour reflects a balance between formal academic tools and informal professional networks.

Major Information Needs

• Research Literature: Peer-reviewed journals, reviews, and preprints remain the most critical sources for staying updated.
• Experimental Protocols: Standardizedlaboratory methods and workflows are essential for reproductivity
• Scientific Data Repositories: Genomic, imaging, and metabolic datasets support data-driven research.
• Technical Documentation: Manuals and tutorials for bioinformatics and statistical tools are increasingly important.
• Collaboration & Funding Information: Grant calls and partnership opportunities support professional growth.

Information Seeking Channels

Formal: Electronic databases (PubMed, Scopus, Web of Science), institutional journal subscriptions, data repositories, and internal training workshops.
Informal: Peer discussions, conferences, seminars, and academic social networks such as ResearchGate and LinkedIn.

Preferred Resources

Scientists favour journals over books, online databases over printed indexes, and direct consultation with collaborators or supervisors over mediated library assistance. This preference highlights the demand for speed, accessibility, and specialized expertise.

12) Results and Findings

The findings reinforce that literature and research data form the core of scientists’ information needs. Both structured databases and informal professional interactions play vital roles in their research process. Digital resources dominate usage patterns due to convenience and up-to-date content.

13) Suggestions

Key challenges identified include:

• Limited access to subscription-based journals
• Information overload from excessive publications
• Time constraints due to heavy research workload
• Uneven technical skills in advanced search techniques

Recommended measures include expanding digital subscriptions, promoting open-access resources, offering regular training in search and data-management skills, and strengthening library liaison services.

14) Conclusion

Scientific information seeking at NCCS is multifaceted, combining traditional scholarly resources with collaborative and digital networks. Research success depends largely on timely access to reliable information and efficient search strategies. Strengthening information infrastructure, improving digital access, and providing targeted training can significantly enhance research productivity and reduce barriers, ultimately fostering innovation and high-quality scientific output.

References:

• Athukorala, K., Hoggan, E., Lehtiö, A., Ruotsalo, T., & Jacucci, G. (2013). Information‐seeking behaviors of computer scientists: Challenges for electronic literature search tools. Proceedings of the American Society for Information Science and Technology, 50(1), 1-11.
• Acheampong, L. D., & Dzandu, M. (2013). Information-Seeking Behaviour of Crops Research Scientists in Ghana. Information and Knowledge Management.
• Abubakar, M. S., & Akor, P. U. (2017). Availability and utilization of electronic information databases for research by agricultural scientists in federal university libraries in North Central Nigeria. Library Philosophy and Practice (e-journal), 1600, 1-34.
• Jamali, H. R., & Asadi, S. (2010). Google and the scholar: the role of Google in scientists’ information‐seeking behaviour. Online information review, 34(2), 282-294.
• Sahu, A. K., Goswami, N. G., & Choudhury, B. K. (2014). Information needs of library users of selective metallurgical institutions in Jharkhand. DESIDOC Journal of Library & Information Technology, 34(IF-0.645), 3-10.
• Makinde, O. B., Jiyane, G. V., & Mugwisi, T. (2019). Factors and challenges affecting the informationseeking behavior of science and technology researchers. Library Philosophy and Practice, 1-26
• Basimalla, S. R. (2000). Communication patterns and information seeking behaviour of health science researchers/scientists: a study of ICMR Institutes.
• Chudamani, K. S., & Nagarathna, H. C. (2006). A model of information use behavior by scientists.

Raju N. Devkar ¹ and Dr. Vishal N. Shinde ²

1. Assistant Professor in Botany, VVM’s S.G. Patil ASC College Sakri Tal. Sakri Dist. Dhule-424304 (MS) India.

Mail ID – rajudevkar094@gmail.com

• Associate Professor in Botany, ADMSP’s Late Annasaheb R D Deore Art’s and Science College, Mhasadi Tal.Sakri, Dist. Dhule- 424304 (MS) India

Mail ID – vishalshinde1001@gmail.com

ABSTRACT: Free radicals are continuously generated in the body during normal metabolic processes and though exposure to environmental factors such as infectious agents, pollution, UV light and radiations. When these harmful free radicals are not neutralized by primary and secondary defence mechanism of body, oxidative stress occurs, which is the reasons for development of various diseases. Plants have many phytoconstituents including saponin, flavonoids and polyphenol with high antioxidants properties. To determination of antioxidant properties of Tribulus spp. extracts (methanol and aqueous) DPPH (1,1- diphenyl 2- picryl hydrazyl) method was used. Whereas DPPH free radical scavenging activity of methanol extracts revealed the strongest as compared to aqueous extracts.

KEYWORDS: Antioxidants, DPPH, Phenolic compounds, Flavonoids, Tribulus rajasthanensis L.

INTRODUCTION:

          Since ancient times, the medicinal properties of plants have been investigated in the recent scientific developments throughout the world, due to their potent antioxidant activities. As antioxidants have been reported to prevent oxidative damage caused by free radicals, it can interfere with the oxidation process by reacting with free radicals, cheating, catalytic metals and also acting as oxygen scavengers ^[1]. Reactive oxygen species (ROS), such as hydrogen peroxide (H₂O₂) and hypochlorous acid (HOCl), and free radicals, such as the superoxide anion (O₂^–) and hydroxyl radical (OH), are produced as normal products of cellular metabolism. Overproduction of free radicals and ROS can lead to oxidative damage to various biomolecules including proteins, lipids, lipoproteins and DNA. This oxidative damage is a critical etiological factor implicated in several chronic disorders such as Cancer, Mellitus, diabetes, inflammatory disease, asthma, cardiovascular disease, neurodegenerative disease and premature aging ^[2,3]. Antioxidants are means for the substances or group of substances that inhibit oxidative damage to a molecule. This defense system is having many modes of classification such as based on their metabolism of action (chain breaking, preventive). Many plants contain large amounts of antioxidants such as vitamin C, vitamin E, lycopene, lutein, carotenoids, polyphenols which play important roles in adsorbing and neutralizing free radicals ^[4]. Beside this, phenolic compounds and flavonoids which have been reported to exert multiple biological effects, including free radical scavenging abilities, anti-inflammatory, anticarcinogenic etc. ^[5].

          Whereas unfavorable environmental conditions for plants, including extreme temperatures, drought, heavy metal exposure, nutrient deficiencies, and high salinity, lead to the excessive production of reactive oxygen species (ROS), which can induce oxidative stress. To counteract this damage, plant cells possess an antioxidant defense system composed of both enzymatic and non-enzymatic components. Non-enzymatic antioxidants act through various mechanisms, such as enzyme inhibition, chelation of trace elements involved in free radical generation, scavenging and neutralization of reactive species, and enhancement of protection via interaction with other antioxidant systems. Among these compounds, secondary metabolites particularly phenolic compounds play a crucial role in protecting plants against oxidative stress ^[6].

          Tribulus rajasthanensis L. belongs to the family zygophyllaceae. It is an annual plant with a wide global distribution and is commonly found throughout India. The species primarily grows wild in dry and arid regions, especially in West Rajasthan, Gujarat, Maharashtra, Uttar Pradesh, and other similar areas ^{[7, 8, 9]}.

          The plant is a decumbent herb with pinnately compound leaves. The leaves typically bear 3–10 pairs of sessile leaflets with unequal, oblique, or rounded bases. Flowers are solitary and pentamerous. The number of stamens ranges from five to ten, and the ovary is five-chambered. The fruit is the most characteristic feature of this genus. At maturity, it divides into five indehiscent mericarps, each containing two to five seeds arranged in a horizontal row.

          According to Bhandari and Sharma (1977), the species is closely allied to T. terrestris L. but can be easily distinguished by its secondary spines and the complete absence of lower pair of spines. Typical specimens with mature mericarp can be easily told apart while the intermediate forms that show the characters of both Tribulus rajasthanensis and Tribulus terrestris are difficult to separate. The typical forms of T. rajasthanensis as a variety of T. terrestris ^[10]. The aim of the present study was to evaluate the antioxidant activity of Tribulus rajasthanensis L. extracts by DPPH methods.

MATERIALS AND METHODS:

Plant materials: The healthy infection free mature plants parts (Fruits, stem, leaves and roots) were collected from the Gomai bank of river, Shahada taluka, Nandurbar District and then they were shade dried and powdered separately in laboratory and kept safely for further research.

Preparation of crude extracts in water: 10 g of dry plant powder was taken in a beaker, 100 ml of distilled water was added, and the mixture was stirred by a magnetic stirrer for 24 h. After that it is filtered by Whatman’s filter paper No.1 and filtrate were centrifuged at 3000 rpm for 15 min. The supernatant was evaporated by rotary evaporator, to get dried form. It was weighed and kept in a refrigerator in sterilized and dark glass containers ^[11].

Preparation of crude extracts in methanol: Solvent extracts were prepared in methanol at room temperature. 10g of dry plant powder was mixed in sufficient quantity of methanol in conical flask. The conical flasks were plugged tightly with cork. Shaken the conical flask properly to mix the content then kept the conical flask for about 30 minutes for the extraction. After 30 minutes it was filtered and filtrate were collected in china dish. These dishes kept on a water bath for some time to evaporate the solvent, after that the methanolic extract were completely dried.

 Antioxidant Activity (DPPH free radical scavenging activity):

          Free radical scavenging activity was determined using the stable 1,1- diphenyl -2-picryl hydrazyl radical (DPPH) according to the method described by Shimada et al. (1992). Butylated hydroxytoluene (BHT) were used as standard control. Various concentrations of the extracts were added to 4 ml of a 0.004% methanol solution of DPPH. The mixture was shaken and left for 30 minutes at room temperature (25 ± 5⁰C) in the dark, and the absorbance was then measured with a spectrophotometer at 517 nm. All determinations were performed in triplicate ^[12,13,14]. antioxidant activity was calculated as the percent inhibition caused by the hydrogen donor activity of each sample according to the following:

Inhibition (%) = [(Absorbance _control – Absorbance _sample)/ (Absorbance _control) ×100

Where: absorbance control is the absorbance of DPPH radical plus methanol; absorbance sample is the absorbance of DPPH radical plus sample extract or standard.

RESULTS:

           Many plants exhibits in vitro and in vivo antioxidant properties owing to their phenolics, vitamins, proteins and pectins contents. In the different literatures, it has been revealed that the antioxidant activity of plant extracts is responsible for their therapeutic effect against cancer and many more disorders. Hence, Tribulus rajasthanensis L. plant extracts were evaluated for in vitro antioxidant activities. DPPH (1,1-diphenyl, 2- picryl hydrazyl) method were used for evaluation of in vitro antioxidant activity.

                  In the present study several biochemical constituents and free radical scavenging activity of Tribulus were evaluated. Free radicals are involved in many disorders like neurodegenerative diseases and cancers. Scavenging activity of antioxidants are useful for the control of these diseases. DPPH stable free radical method is a sensitive method to evaluate the antioxidant activity of plant extracts. DPPH radical scavenging activity of methanolic extracts of Tribulus showed strongest while some parts of plants revealed moderate antioxidant properties in aqueous extracts.

DISCUSSION:

           medicinal plants have been used to treat a wide range of disorders since ancient times. From simple cold to complex diseases these plants have served as effective therapeutic agents ^[15]. Tribulus rajasthanensis L. as a well- known medicinal plant, was selected for this study primarily because of it’s antioxidants potential. Plant extracts were evaluated for in vitro antioxidant activities. DPPH Method provides a good assessment for evaluation of in vitro antioxidant activity. It is based on reaction between antioxidant with nitrogen centered free radical i. e. DPPH (1,1 diphenyl, 2- picryl hydrazyl). That’s why in this experiment; we evaluated the in vitro antioxidant and radical scavenging activities of Tribulus spp. methanol extract using DPPH Method.

           Oxidative stress is a deep-rooted cause of various disorders, including rheumatoid, arthritis and inflammation, neurodegenerative disease, diabetes, cancer, aging etc. Preventing the production of reactive oxygen species (ROS) and reactive nitrogen species (RNS) during cellular metabolism is critically important. The widespread use of medicinal plants across different therapeutic contexts encouraged us to investigate Tribulus spp. to assess its antioxidant and free radical scavenging properties. Our result revealed the tremendous potential of this plant in reducing free radical through DPPH, possibly due to its high polyphenol content. However, more investigations should be carried out to clarify the specific correlations between the plant bioactive and the observed biological activities.

References:

1. Patel V. R., et al. (2010); Antioxidant activity of some selected medicinal plants in Western region of India. Advances in biological research, 4(1): 23-26.
2. Ghimire B. K., et al. (2011); A comparative evaluation of the antioxidant activity of some medicinal plants popularly used in Nepal. Journal of medicinal plants research,5(10): 1884-1891.
3. Patel V. R., et al. (2010); Antioxidant activity of some selected medicinal plants in Western region of India. Advances in biological research, 4(1): 23-26.
4. Agrawal S. S., et al. (2008); Antioxidant activity of fractions from Tridax procumbens. Journal of Pharmacy research, 2: 71-73.
5. Patel V. R., et al. (2010); Antioxidant activity of some selected medicinal plants in Western region of India. Advances in biological research, 4(1): 23-26.
6. Chaves N., et al. (2020); Quantification of the antioxidant activity of plant extracts: Analysis of sensitivity and Hierarchization Based on the method used. MDPI,9(76): 1-15.
7. Lokhande K. D., et al. (2014); Evaluation of antioxidant potential of Indian wild leafy vegetable Tibullus terrestris. Int J Adv Pharma Biol Chem., 3: 2277- 4688.
8. Hussain A. A., et al. (2009); study the biological activities of Tribulus terrestris extracts. World Acad Sci Eng Technol., 57: 433-435.
9. Mohammed M. J. (2008); biological activity of saponins isolated from Tribulus terrestris (fruit) on growth of some bacteria. Tikrit Journal of Pure Science, 13(3): 17-20.
10. Varghese M., et al. (2006); Taxonomic status of some of the Tribulus species in the Indian subcontinent. Saudi journal of biological sciences, 13(1):7-12.
11. Abdulqawi L.N. and Syed A.Q. (2021); Evaluation of Antibacterial and Antioxidant activities of Tribulus terrestris L. Fruits. Research J. Pharm. and Tech.,14(1):331-336.
12. Ghimire B. K., et al. (2011); A comparative evaluation of the antioxidant activity of some medicinal plants popularly used in Nepal. Journal of medicinal plants research,5(10): 1884-1891.
13. Javed S. R., et al. (2018); In vitro and in Vivo assessment of free radical scavenging and antioxidant activities of Veronica persica Poir. Cellular molecular biology, 57-64.
14. Patel V. R., et al. (2010); Antioxidant activity of some selected medicinal plants in Western region of India. Advances in biological research, 4(1): 23-26.
15. Javed S. R., et al. (2018); In vitro and in Vivo assessment of free radical scavenging and antioxidant activities of Veronica persica Poir. Cellular molecular biology, 57-64.

Hitesh N. Wankhede^a, Harshal S. Gawale^b, Rajendra R. Ahire^a, Anup J. More^a,*

^aDepartment of Physics, VVM’s S.G.PatilArts,Science and Commerce College Sakri 424304 Dist. Dhule, KBC NMU Jalgaon, Maharashtra, India

^bDepartment of Physics, JET’s Z.B.Patil college, Dhule 424002, KBC NMU Jalgaon, Maharashtra, India

Abstract

The growing global demand for energy has intensified the need for advanced and efficient energy storage technologies. Supercapacitors and batteries have gained considerable interest due to their essential role in modern energy storage systems. The effectiveness of these devices largely depends on the characteristics of the electrode materials, such as high specific capacitance, superior electrical conductivity, large surface area, abundant availability, and favorable electrochemical properties. While cobalt-based nanomaterials offer high conductivity, abundant resources, and strong capacitance performance for supercapacitor electrodes, limitations such as structural degradation and insufficient power density remain unresolved. This paper reviews on advances in cobalt Sulfide based nanomaterials electrode materials for supercapacitors, with a focus on their preparation methods, electrochemical performance and properties. It focuses on methods to enhance the electrochemical performance of these materials. It shows that synergistic effect can improve the morphology of nanomaterials can significantly boost their performance, with mesoporous structures. Key findings from the literature on batteries and supercapacitors are summarized, highlighting Cobalt sulfide-based materials integrated with carbon nanotubes, graphene, reduced graphene oxide, MAX phase (Class of 2D inorganic compounds comprising atomically thin layers of transition metal carbides, nitrides, or carbonitrides) shortly known as MXene, Metal Organic Framework(MOF), nickel foam and metal elements such as nickel, manganese, etc.

Keywords:Supercapacitor, cobalt composites, specific capacitance, energy density,nanomaterials, hydrothermal

1. Introduction

After the industrial revolution demand of energy completely rely on energy extracted from fossil fuel (oil, gas and coal) but it causes a severe effect on human health like cardiovascular disease, respiratory syndrome, cancer, reproductive effects, etc. and it can happen due to the evolution of carbon dioxide, carbon monoxide, CFC, and other toxic gases which may leads to greenhouse effect. To get ride from this problem we need to adopt renewable energy resources like hydroelectric energy, solar energy, wind energy, geothermal energy, tidal energy, and biomass energy.^[1] There is a challenge in effectively storing energy extracted from these resources. To address this issue electrochemical energy storage system (EES), namely supercapacitors and batteries have become crucial technologies.^[2] Energy density of batteries is higher than the supercapacitor but power density of batteries is lower than the supercapacitor so for rapid charging and discharging applications supercapacitor are more convenient. Continuous research progression in this area is due to wide range of applications such as industries, medical field, military, automobile sector, etc.

In recent days automobile sector mostly relies on lithium-ion batteries due to higher energy density and safe during handling.  Lithium is a key part of batteries that runs electric vehicles but due to limited availability of lithium it really hard to keep up with demand and supply. Researchers are continuously working on replacement of lithium to alkali metals like sodium cause abundant in nature and low cost but sodium ion batteries having poor cyclic performance.^[3] In comparison to batteries supercapacitor having some positive features like fast charging- discharging cycles. Supercapacitor require 1-10 s and batteries require 0.5-5 hr. charging -discharging time. Power density defines how quickly energy can be delivered or receive per unit mass (W/kg): supercapacitor having higher power density 500-10000 W/kg and batteries having power density less than 1000 W/kg. Supercapacitor have longer lifetime more than 500,000 hrs. and batteries 500-1000 hrs. Energy density defines amount of energy stored per unit mass: energy of batteries 10-100 Wh/kg more than supercapacitors 1-10 Wh/kg.^[4] The Ragone plot shown in graph 1. provide the information about behavior of electrochemical energy storage devices power density and energy density.^[5]

Graph 1. Ragone plot of different electrochemical energy conversion systems.^[5]

Conventional capacitor having lowest energy density and higher power density in comparison to other electrochemical energy storage devices. Supercapacitor having lower energy density and higher power density also batteries having higher energy density and lower power density compared to other electrochemical devices.^[6] To overcome the limitations of conventional batteries, supercapacitors have emerged as a promising electrochemical energy storage device. Unlike batteries, supercapacitors require electrode materials that exhibit high electrical conductivity, a large electrochemically active surface area, and well-tuned porosity to facilitate rapid ion transport. In addition, excellent thermal and chemical stability of the electrode material is essential to ensure long-term performance and safety. The development and fabrication of such advanced electrode materials play a crucial role in enhancing the energy density and overall efficiency of supercapacitor systems.

2. Synthesis Method

Cobalt sulfide (CoS) can be synthesized through several methods, depending on the desired properties and the form of the material. In this review article most of the materials are synthesize by hydrothermal method, solvothermal method, microwave induced synthesis, chemical bath deposition (CBD) etc.

2.1 Hydrothermal Method

This is a popular method for synthesizing CoS nanostructures, such as nanoparticles, nanowires, nanotubes etc. It involves a chemical reaction in an aqueous solution at elevated temperature and pressure. It involves crystalizing materials from aqueous solutions at high temperatures and pressures within a sealed and compact vessel. This method has some advantages facilitates the growth of nanostructured materials with controlled morphologies.

Fig. 1. Schematic representation of hydrothermal synthesis method^[7]

 It provides precise control over particle size and morphology, form crystalline structures at relatively low temperatures and allows to enhance material properties. This method also has limitations, requires specialized equipment to withstand high pressures. Extended reaction times may be necessary to achieve desired crystallinity.^[7]

2.2 Solvothermal Method

In this method chemical reaction carried out in an autoclave which sealed vessel using a different solvent at high temperature and controlled pressure. Due to this conditions nucleation and growth of materials of materials occurred in a controlled manner. This method having some advantages, it allows precise control over particle size, crystallinity, shape and growth of pure materials. It suitable for synthesis of wide range of nanostructure of metal sulfides, oxide and hydroxide.^[8]This method has some limitations like the process is time consuming and it run with help of high pressure; scalability is also a problem.

2.3 Microwave-Assisted Synthesis Method

Microwave-assisted synthesis involves rapid heating of reactants using microwave radiation, enabling uniform nucleation and growth of nanomaterials. Heating occurs due to the interaction of 2.54 GHz microwave energy with polar molecules and ions via dipole polarization and ionic conduction mechanisms. This technique offers reduced reaction time, uniform heating, and high energy efficiency. However, limitations include restricted precursor selection and challenges in large-scale production.^[9]The method has been effectively applied to synthesize metal sulfide nanoparticles, metal oxide nanoparticles etc. for high-performance supercapacitor electrodes.

2.4 Chemical Bath deposition (CBD) Method

The chemical bath deposition (CBD) technique is a low-cost and simple method used to deposit thin films of materials from a solution. In this method, the substrate is immersed in a chemical bath containing metal ions and a suitable complexing agent. Controlled chemical reactions in the solution lead to the slow and uniform deposition of the material onto the substrate surface. The deposition occurs due to the controlled release of ions and subsequent nucleation on the substrate. Parameters such as bath temperature, pH, concentration of reactants, and deposition time play an important role in determining the thickness, morphology, and quality of the deposited film. CBD has several advantages. It is simple, cost-effective, and does not require vacuum or high-temperature conditions. It allows large-area and uniform film deposition and is suitable for coating complex-shaped substrates.^[10] However, the technique has some limitations, such as poor adhesion, lower crystallinity, and limited control over film thickness compared to advanced deposition methods.

3. Electrochemical performance analysis

In recent years metal sulfide and oxides-based electrodes materials are more prominent for supercapacitor applications due to their excellent redox reversibility, high electrical conductivity, excellent morphology, and high specific capacitance. This review article focuses on cobalt sulfide-based electrode materials for supercapacitor application.^[11,12] Different techniques are used to tune the morphology of various materials including hydrothermal, solvothermal, supercritical fluid synthesis, CBD, microwave assisted synthesis technique. Morphology of materials can be responsible for effective energy storage and improve the electrochemical performance of electrode materials. In this article a few cobalt sulfide-based electrode materials, some remarkable morphologies like nanowires, nano-tubes, nano-sheets,flakes, and nano-flower-like structures have been reported. A silver fungus-like cobalt sulfide (CoS) nanostructure was successfully synthesized via solvothermal method and use as an electrode material for high-performance supercapacitors. The unique fungus-like morphology provides a large active surface area and abundant electroactive sites, which enhance electrolyte penetration and facilitate fast charge transport. As a result, the silver fungus-like CoS (SFC) electrode exhibits a high specific capacitance of 350.4 F g⁻¹ at a current density of 1 A g⁻¹. The device SFC//AC delivers an energy density of 45.2 Wh kg⁻¹ at a power density of 1500 W kg⁻¹, provides excellent energy storage capability.^[13] A cobalt sulfide nanoparticles synthesize by hydrothermal route and calcinated at 200 ⁰C for 1 hr. form a hexagonal phase of CoS. As a result, the CoS electrode delivers a high specific capacitance of 285.8 F g⁻¹ at a current density of 2 A g⁻¹. Furthermore, the electrode demonstrates excellent cycling stability, retaining 96% of its initial capacitance even after 5000 galvanostatic charge–discharge cycles, indicating strong structural integrity and reversibility. The device made up of CoS/CC//AC achieves an energy density of 25.8 Wh kg⁻¹ andhigh-power density of 14,800 W kg⁻¹, highlighting its capability to store substantial energy while delivering it rapidly.^[14]Nickel cobalt sulfide is high promising material electrode for supercapacitor application good cycling stability. NCS-180 synthesize at 180^oC display urchin like crystalline structure provide more electroactive sites and good electrochemical performance.Owing to these structural advantages, the NCS-180 electrode delivers a high specific charge capacity of 664.30 C g⁻¹ at a current density of 1 A g⁻¹, indicating better Faradaic charge-storage capability. The electrode demonstrates good long-term cycling stability, retaining 93.30% of its initial capacity after 6000 galvanostatic charge–discharge cycles, provides structural stability during repeated cycles. NCS-180//AC system achieves an energy density of 50.35 Wh kg⁻¹ with a corresponding power density of 750 W kg⁻¹.^[15]Dumb-bell shaped 10-20 nm sized cobalt sulfide (CoS) particle prepared by solvothermal route exhibit specific capacitance of 310 F/g at current density of 5 A/g and 95% of capacitance retention after 5000 charge–discharge cycles. Device made up of Cos//AC provide specific capacitance of 5.3 Wh kg⁻¹ and a high-power density of 1800 W kg⁻¹ with an excellent electrochemical stability.^[16] High-performance nickel–cobalt sulfide–terephthalic acid (NCS–BDC) composite electrode synthesized via a simple solvothermal route for energy storage devices like supercapacitor. Highly mesoporous structure creates more active site for reaction and provides more surface area for transmission of ions. NCS-BDS has good electrochemical properties. It has specific capacitance 1267.25 F g⁻¹ at a low current density of 0.5 A g⁻¹. Electrode shows good cycling stability, maintain 92% of its initial capacitance after 5000 charge–discharge cycles. NCS-BDC based device achieved high energy density 52.29 Wh kg⁻¹.^[17] Hydrothermal route utilizes to synthesize cobalt sulfide/reduced graphene oxide (Co₃S₄/rGO) nanocomposite. As a result, the CoS/rGO nanocomposite provide an ultrahigh specific capacitance of 1560 F g⁻¹ at a current density of 1 A g⁻¹ and also the electrode exhibits good cycling stability, retaining 89% of its initial capacitance after 5000 charge–discharge cycles. Device achieves an energy density of 40.2 Wh kg⁻¹ and a power density of 804 W kg⁻¹.^[18]

CoS nanosheet fabricated on metal organic framework on nickel foam (NF) by hydrothermal route. CoS/NF electrode display a high specific capacity 1359 C g⁻¹ at the current density of 2 A g⁻¹, and excellent cycling stability of 89.4% after 4000 cycles. A device fabricated by CoS/NF positive electrode and AC as a negative electrode shows high energy density of 57.4 W h kg⁻¹ at a power density of 405.2 W kg⁻¹.^[19]CoS/MXene was synthesize by supercritical fluid synthesis method. Electrochemical performance of CoS/MXene,CoS/MXene/PANI and CoS/MXene/PEDOT was studied. CoS/MXene/PANI electrode delivered specific capacitance of 407 F g⁻¹ at current density of 2 A/g with cycling stability of 97% after 10000 cycles. Also, CoS/MXene/PANI electrode delivered specific capacitance of 630 F g⁻¹ at current density of 2 A/g with cycling stability of 96% after 10000 cycles useful for supercapacitor application.^[20]Ni-based flower-like nitrogen-rich carbon (NCNi) synthesized on a carbon felt (CF) substrate through a hydrothermal route. EC-NiCoS@NCNi@CF electrode shows specific capacitance of 190.78 F g⁻¹ at current density of 0.5 A/g having cycling stability of 92.2% after 4000 cycles. Device delivered energy density of 64.77 W h kg⁻¹ and power density of 420.13 Wkg⁻¹.^[21]Co-Ni-S composite electrode prepared through a two-step process involving electrodeposition followed by hydrothermal sulfurization which brings more cobalt active sites for redox reaction.The Co-Ni-S composite electrode delivers high specific capacitance of 3586 F g⁻¹ at 1 A g⁻¹ and 97% capacity retention over 5000 cycles.^[22]The rGO/NCS/PANI electrode provide a high specific capacitance of 628 F g⁻¹at a current density of 10 A g⁻¹ and retentivity of 84 % after 5000 charge-discharge cycles showing excellent cycling stability.^[23] Two-stage hydrothermal method used to synthesize nickel–cobalt sulfide nanostructures to enhance the electrochemical properties of materials. Electrode achieve specific capacitance of 8.1 F cm^-2 at current density 5mA cm^-2. Nickel–cobalt sulfide electrodes as the positive electrode and activated carbon as the negative electrode delivered high energy density of 51.2 Wh kg⁻¹ at a power density of 262.5 W kg⁻¹.^[24] By utilizing different reaction conditions Nickel cobalt sulfide (NCS) microspheres are successfully synthesized by an easy one-step hydrothermal method . NCSW-200 electrode delivered a specific capacitance of 369 F g⁻¹ at current density of 0.5 A g⁻¹ having capacitive retention of 67% after 2000 cycles.^[25] Two step facial hydrothermal method used to synthesize nickel cobalt sulfide nanoparticles (NCS) deposited on nitrogen and sulfur doped graphene which provides a synergistic effect and improve electrochemical parameters. Electrode delivered a specific capacitance of 630.6 F g⁻¹ at 1 A g⁻¹ current density with retention of 110 % after 10000 cycles. Also, energy density of 19.35 Wh kg⁻¹ at a power density of 235.0 W kg⁻¹ showing exceptional capacity for supercapacitor application.^[26]

Ni-Co-S/Co(OH)₂ electrode synthesize by two step facial method with synergistic effect provides excellent electrochemical performance shows a specific capacitance of 1560.8 F g⁻¹ at 1 A g⁻¹ current density with retention of 88% after 10000 cycles. A device shows high energy density of 48.8 W h kg⁻¹ at a power density of 800 W kg⁻¹ with excellent cycle stability.^[27] Hydrothermal route employed for successfully synthesis of NiCo₂S₄ polyhedral structures for application to supercapacitor and lithium-ion battery. Electrode exhibit a specific capacitance of 1298 F g⁻¹ at 1 A g⁻¹. Capacity retention of 90.44% after 8000 cycles.^[28] Etching/ ion exchange method used to synthesize Ni-Co-S nanosheets on activated carbon cloth for fabrication of supercapacitor application.The Ni-Co-S/ACC electrode can deliver a specific capacitance of 2392 F g⁻¹ at the current density of 1 A g⁻¹ and also have retentivity of 82 % after 10000 cycles. Device Ni-Co-S/ACC as positive electrode and activated carbon as negative electrode display high energy density of 30.1 Wh kg⁻¹ at power density of 800.2 W kg⁻¹.^[29] Hierarchical NiCo₂S₄@Co(OH)₂ nanotube structure on Nickel foam have been synthesized through a facial method. Synergistic effect of NiCo₂S₄ nanotubes and Co(OH)₂ nanosheets delivered a superior electrochemical performance having specific capacity of 9.6 F cm^-2 at current density of 2 mA cm^-2 with capacitive retention of 70.01% after 5000 cycles.^[30]One-step hydrothermal method utilize for the synthesis of the flaky attached hollow-sphere structure NiCo₂S₄ electrode materials.The NCS-10 electrode atPh 10 shows an excellent specific capacitance of 1366 F g⁻¹ at the current density of 1 A g⁻¹ at high retention of 89.8% after 2000 cycles.^[31]The poor performance and cyclic stability of the materials have limit practical applications so need to improved quality of electrode by improving morphology. Carbon flakes with an ultrahigh surface area prepared from eggplant utilize as a substrates to enhance the electrical conductivity of NiCo₂S₄ nanosheets. Exhibit a specific capacitance of 1394.5 F g⁻¹ at 1 A g⁻¹ and cyclic stability of 124% after 10000 cycles. Delivered a high energy density of 46.5 Wh kg⁻¹ at a power density of 801 W kg⁻¹.^[32]For high performance supercapacitor require high specific surface areas, high redox active sites, efficient electrons-ions migration channels. Facial two step hydrothermal route used to fabricate highly porous Co₃S₄@Ni₃S₄ heterostructure nanowire arrays prepared onto Ni foam.Delivered specific capacitance of 3.6 F cm^-2 at energy density of 0.8 mA cm^-2get 80% capacitive retention after 5000 charge-discharge cycles.^[33]Hydrothermal method and potentiostatic deposition utilize to grow hierarchical polyaniline-coated NiCo₂S₄ nanowires on carbon fiber “NiCo₂S₄@PANI/CF”. NiCo₂S₄@PANI/CF material electrode have multiple electroactive sites so it enhances electrochemical performance of electrode as well as device. Electrode display high specific capacitance value 1823 F g⁻¹ at 2 mA cm^-2 and excellent cycling stability of 86.2% after 5000 cycles. Device NiCo₂S₄@PANI/CF delivers a high energy density of 64.92 Wh kg⁻¹ at a power density of 276.23 W kg⁻¹.^[34]NiCo₂S₄, a spinel-structured has a high specific capacity, it has promising characteristic of electrode material for supercapacitors but due to poor electrical conductivity need to tune its morphology. In this work NiCo₂S₄ deposited on the surface of carbon nanotubes (CNTs) to enhance the electrical conductivity. CNTs@NiCo₂S₄ delivered specific capacitance of 216.4 mAh g⁻¹ at 1 A g⁻¹with cyclic retention of 75 % after 2000 cycles.^[35]Microwave assisted technique is used to synthesize NCS/CNTs-H electrode followed by post annealing to anchor NCS nanoparticles on multiwall CNTs. This structure enhances electrochemical performance of electrode; it delivered high specific capacitance of 1261 F g-1 at 1 A g-1 with retention capability of 84.4%. Device NCS/CNTs-H//AC deliver a high energy density 58.4 Wh kg-1 at the power density of 400 W kg-1. NCS/CNTs-H offer good electrochemical performance so it stands high for supercapacitor electrode.^[36]Microwave assisted technique utilizes to synthesis of honeycomb-like NCS/graphene composites which use as ultrahigh supercapacitor electrode. NCS/G-H exhibit high specific capacitance of 1186 F g^-1 at 1 A g^-1 and cyclic retention of 89.8% and delivered energy density of 46.4 Wh kg^-1.^[37]Sonochemical method used for synthesis of cobalt sulfide nanomaterial and cobalt phosphate nanoflakes and composite of both form a CoS/Co₃(Po₄)₂ electrode. Composite consisting 75% of CoS and 25% of Co₃(Po₄)₂ composition, shows a specific capacitance of 728.2 F g^-1 at current density of 0.6 Ag^-1 with capacitive retention of 95.10% after 5000 cycles. Device provides remarkable specific energy of 63.93 Wh kg-1 along with specific power of 850 W kg^-1at 1 Ag^-1.^[38]MnCo2S4@CoNi LDH core shell heterostructure synthesis on nickel foam using hydrothermal reaction and electrodeposition technique. MnCo2S4 nanotubes provide excellent electrical conductivity whereas CoNi LDH nanosheets provide more electrochemical active sites for better supercapacitive performance. The electrode provides a specific capacitance of 1206 C g⁻¹ at 1 A g^-1 and excellent cycling performance with 92% retention after 10 000 cycles.^[39]Cobalt sulfide nanostructure synthesizes by one step hydrothermal method for different temperature ranging from 160^oC to 220^oC. Sample get high crystallinity and hexagonal structure at 220^oC.  A high specific capacitance deliver of 1583 F g^-1 at a current density of 1 A g^-1 with good cyclic performance for supercapacitor application.^[40]

Sheet-like nickel cobalt sulfide nanoparticles synthesize by a two-step hydrothermaltechnique provide rich sulfur vacancies.NiCo₂S₄ nanosheets provide good specific capacitance of 971 Fg^-1 at 2 A g^-1 and an excellent cyclic stability of 88.7% after 3500 cycles.^[41] By facial solvothermal method mixed nickel-cobalt sulfide (NCSs) prepared for supercapacitor application. The mixed NCS prepared at a nickel: cobalt molar ratio of 3:1 exhibited a specificcapacitance of1345 Fg^-1 at a current density of 2 A g^-1 with 95% of its initial capacitance after 3000 charge-discharge cycles.^[42] Cobalt sulfide composes with different metals such as copper Cu and manganese Mn fabricated by hydrothermal method on nickel foam provide a unique morphology of nanoflakes of different texture. Mn-CoS-3/NF boost the specific capacitance of 2379 F g^-1 at 1 A g^-1 with capacitance retention about 65% after 5500 cycles comparing to 48% of CoS-3/NF and 55% Cu-CoS-3/NF. Mn-CoS-3/NF deliver high surface area, low internal resistance, flaky nanostructure. Mn-CoS-3/NF//AC/NF device deliver energy density of 17.94 Wh kg^-1 and power density of 6405 W kg^-1.^[43] Twostep hydrothermal method used to synthesis of cobalt sulfide layered flower-like morphology binder-free Co₉S₈ electrodes deposited onto nickel foam with an enhanced specific capacity of 1611.87 F g^-1at 1 mA cm^–2.^[44]CoS/G nanocomposite successfully synthesize by one pot hydrothermal method. CoS nanosphere offers specific capacitance of 390 F g^-1 and CoS on graphene shows excellent specific capacitance 739.83 F g^-1 with capacitance retention of 91.2 % after 3000 cycles.^[45] Dandelion likeNiCo₂S₄@PPy/NF microsphere synthesize by hydrothermal method. Electrode shows remarkable specific capacitance of 2554.9 F g⁻¹ at 2.54 A g⁻¹ with capacitive retention of 92% after 10000 cycles. Device delivered an energy density of 35.17 Wh kg−1 at a power density of 1472 W kg−1.^[46]Electrochemical performance of MXene tune by CoS synthesize on Mxene by one step solvent thermal method. Delivered a specific capacitance of 1320 F g⁻¹ at a current density of 1 A g⁻¹ and it shows cyclic performance with 78.4% after 3000 cycles device delivered an energy density 28.8 Wh kg^-1 and 800 W kg^-1.^[47] A simple two step hydrothermal process utilize to prepared a binder-free graphene-nanosheets wrapped Co3S4 hybrid electrode is prepared on conductive Ni-foam. structure of the Co3S4-rGO shows a specific capacitance of 2314 F g⁻¹ with 92.6% cyclic stability after 1000 cycles. Device delivered energy density of 54.32 Wh kg^-1and power density of 6250 W kg^-1.^[48]A two-step hydrothermal method uses to synthesize nickel and cobalt sulfide with different ratios of nickel and cobalt. NC24 sample with the Ni/Co ratio of 1:2 hollow nanotube arrays composed of NiCo2S4 provides nanorod array structure which gives excellent specific capacitance of 1527 C g⁻¹ at 1 A g⁻¹ with capacitive retention of 93.81% after 2000 cycles. Symmetrical supercapacitor from this electrode delivers high energy density of 67.5 Wh kg^-1.^[49]

A simple chemical bath synthesis methodutilizesto synthesize flaky nickel cobalt sulfides (NiCo_xS_y) materials display specific capacitance of 1196.1 F g⁻¹ at 1 A g⁻¹ with cyclic retention of 97.5% after 4000 cycles.^[50] A novel urchin-like hollow nickel cobalt sulfide (NiCo₂S₄) fabricated by a facile template-free methodthis structure improves electrochemical performance of electrode as well as device. Electrode display a specific capacitance of 1398F g⁻¹ at 1 A g⁻¹ with excellent cyclic stability of 74.1% after 5000 cycles.^[51]Flower like NiCo₂S₄ prepared by rapid chemical precipitation assisted annealing method deliver a specific capacitance of 2198.9 F g⁻¹ at 1 A g⁻¹. A device NiCo₂S₄//AC deliver a high energy density of 38.2 Wh kg⁻¹ at power density of 400 W kg⁻¹.^[52] One step hydrothermal method used to fabricate reduced graphene oxide/nickel-cobalt sulfide (rGO/NiCo₂S₄). Needle like structure of NiCo₂S₄ have many nanoparticles very well adhered to reduce graphene oxide. Prepared electrode has porosity and it leads to excellent conductivity possess a specific capacitance of capacitance of 813 F g⁻¹ at 1.5 A g⁻¹ with good cyclic stability of 84.3% after 2000 cycles. Device shows a high energy density of 40.3 Wh kg⁻¹ and power density of 375 W kg⁻¹.^[53] Hydrothermal method used to fabricate NiCo₂S₄ nanorodon nickel foam (NF). It shows excellent specific capacitance of 3093 F g⁻¹ at 5 A g⁻¹ with cyclic stability of 41.7% after 2000 cycles. Device shows a high energy density of 39.3 Wh kg⁻¹ and power density of 800 W kg⁻¹.^[54] A facial two step chemical bath deposition technique used to synthesize a NiCo₂S₄ nanowire arrays grown on 3D graphene foams (3DGF) for supercapacitor application. It offers a high specific capacitance of 1454.6 F g⁻¹ at 1.3 A g⁻¹ with cycling stability of 96% after 3000 cycles.^[55] Hydrothermally synthesize Cobalt sulfide Co₃S₄ nanosheet decorated with nitrogen doped carbon dots featuring rich sulfur vacancies and copper doping (V-Cu-Co₃S₄/NCDs). It delivered a specific capacitance of 619.2 C g⁻¹ at 1 A g⁻¹ with capacitive retention of 86.9% after 10000 cycles.^[56] An electrodeposition hydrothermal techniqueuses to deposit NiCo2S4 nanoarrays on carbon nanofibers with different morphologies, carbon nanofibers have high surface-area-to-volume ratios, excellent mechanical strengths, and remarkable flexibilities so it provides anexcellent electrochemical property. NCS@C shows a specific capacitance of 334.7 mAh g⁻¹ at current density of 2 A g⁻¹ and the device exhibited high energy and power densities of 12.91 Wh kg⁻¹ and 358 W kg⁻¹.^[57] Hydrothermal synthesis of cobalt sulfide nanoparticle on carbon cloth with varying precursor ratios, hydrothermal temperature and time. Structural analysis confirms the formation of hexagonal phase of CoS.Co:S ratio of 1:2 at 160⁰C for 15 h exhibited the highest specific capacitance of 424 F g^-1 at 1 A g^-1 with excellent cyclic stability of 90% after 1000 cycles.^[58] Hydrothermal method uses to prepared NiCo₂S₄ flower-shaped crystal nickel–cobalt sulfide on nickel foam. It shows a specific capacitance of 3867.8 F g^-1 at 1 A g^-1 with cyclic retention of 90.57% after 2000 cycles.^[59]

^{Table.1. Highlight electrochemical parameters of Cobalt sulfide-based electrodes.}

Hydrothermal treatment utilizes to fabricate cobalt sulfide (Co₃S₄) from cobalt oxide as a precursor for 20 hr. duration and it’s a more suitable for super capacitor application as a cathode. It exhibits a specific capacitance of 480.40 F g^-1 at 1 A g^-1.^[60]

Cobalt sulfide–based materials and their composites exhibit high specific capacitance values, making them promising candidates for super capacitor electrode applications. Graph 2. below illustrates the energy density achieved by various cobalt sulfide–based electrodes, the energy density indicates how much energy a super capacitor can stored per unit mass. Energy density of these materials can be effectively tuned by selecting suitable substrates and combining cobalt sulfide with other functional materials. Graph 3. Below illustrates the power density of cobalt sulfide-based electrodes, power density indicates how quickly stored energy can be delivered.

^{Graph 2. Represent energy density of Cobalt based electrodes.}

^{Graph 3. Represent power density of Cobalt based electrodes.}

4. Conclusion

   Cobalt sulfide- based nanomaterials are promising supercapacitor electrodes owing to their high redox activity, good conductivity, tunable nanostructures. Morphology control and synergistic engineering through composites and heterostructures significantly enhance electrochemical performance, while future efforts should focus on scalable synthesis and long-term device stability.

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Rathod P.P.

Department of Zoology

VVMs Sitaram Govind Patil Arts, Science & Commerce College Sakri Di. Dhule

E mail- pradiprathod1309@gmail.com

Abstract

The distribution of spider’s diversity in Sakri forest region of Sakri, Dhule District has been studied. Sakri forest is located to the West of Dhule city. In this forest we are collecting and an identified different type of spiders belonging to family thomisidae. This study was tried to analyze distribution of spider’s diversity. In Sakri forest nine different species of spiders were identified namely Thomisus, Xysticus, Thomisus projectus, Philodromus Bhagriathai, Thomisus pooneus, Synaema decorate, Tmarus kotigeharus, Tbeilus Simon, Genus Synaema, were observed. Out of these Thomisus and Tmarus kotigeharus was most abundant in study region.

­­­­­­­­­­­­­­­­­­­­­­­­Key words: – Thomisidae, Tmarus kotigeharus, Sakri forest, spider diversity

Introduction: –

Spider taxonomy is the alpha taxonomy of the spiders, members of the Araneae order of the Arthropod class Arachnidae with about 40,000 describe species. However, there are likely many species that have escaped the human eye to this day and many. The current global list of spider fauna is approximately 42,055 families. The spider fauna of India is represented by 1520 spider species belonging to 377 genera and sixty families. (Chetia and Kalita 2012) describes the identification of the spider assemblages with respect to their diversity and distribution in the semi evergreen forest, Gibbon Wildlife Sanctuary, Assam, India. According to survey the first approach to prepare checklist of GWS. 120 species representing 49 genera under 16 families, 16 specimens were identified till genera. Families indicating excessive member of species are Thomisidae (24 species under 9 genus) followed by Araneidae (22 species under 8 genus), while family Gnaphosidae indicates highest number of genera (10 genera). (Kujur R. and Ekka A. 2016).

 (Gajbe 2016) The spider fauna of Karhandla is being reported for the first time. During some faunal surveys of invertebrates carried out in this region from November 2014 to October 2015, some species of spiders were observed and identified. These spiders are mainly of two types, hunting spiders and web-making spiders.

Family Thomisidae: –

This is large family with more than 3000 known species. 62 are found in this region. They are not active hunters and make more use of camouflage techniques than other spiders. Crab spiders can be found on flowers or leaves of plants. Because they sit on easily spotted places they are also easily to catch by the predator. There eye sight is excellent develop. They have normally to big front eye.

All spiders use their fangs to inject venom; the fangs of many more than 3,500 spider species in the United States are incapable of penetrating human skin. Spiders are rarely aggressive towards humans they bite only in self defense. Spider silk is the strongest fiber in nature, five times stronger than steel, yet so times thinner than human hair. A unique anatomical feature of spider is pedipalps. The two of these appendages positioned just outside the fangs. The male spiders use its pedipalps as miniature boxing gloves, in courtship dance.

Material and Methods: –

The following study of crab spider family Thomisidae is based on morphological characters of crab spider and also phylogenetic analysis of spiders. Through this project and attempt has been made to focus on study of crab spider in.

Study area: –

The Sakri forest is situated about 55Km West of Dhule city at a latitude of 20-59’-28”N and longitude 74⁰-18’.36’’ E. Longitude and covers an area of the forest is fulfilling with diversity of different insects, animals and plant species. Sakri forest faces extreme variation in climatic condition with hot summer and very cold winter as well as average rainfall. The annual average rainfall in the forest ranges between 514.1mm to 525mm and temperature ranges between 16⁰C to 31⁰C.

Collection and identification of crab spider species of family Thomisidae: –

            A number of methods are available for collection of spiders from a wide variety of environments. The type of vegetation determines the kinds of spider crab spider (Thomisidae) were collected from the above gardens. The capture and collected spider species kept into dry container or directly transfer into absolute alcohol. Method suggested by Koh (1989) was namely referred for the collection and preservation of crab spider

Result and discussion: –

Thomisus species: –

            Reddish brown, as wide as long, lateral projection present at ocular region. Lateral side darker that median portion. Fumer, tibia and metatarsi of leg I and II darker, Patella lighter. Sternum heart shape, yellowish, anterior margin concave, widest at coxa II, is tapering towards III and IV. Maxillae longer than wide, brownish, outer margin concave slightly projected at the lower end. Labium brownish, longer and wide, reaching more than half the length of maxillae. Typical pentagonal shaped, yellowish brown, five spots present on dorsum. Behind posterior sigilla of blackish transverse patch. Anterior half is brownish, posterior half paler, bounded by darker lateral patch. Book lungs are darker, spinnerets are darker.

Xysticus minutes: –

Cephalothorax is light brown, legs greenish abdomen light brown. Total length 2.20 mm. Carapace 1.00mm long, 1.00mm wide; abdomen 1.30 mm. long 1.20mm wide. Eyes black round ring with dirty white tubercle; ocular quad slightly wider than long, space of the anterior median eyes a little wider than that of posterior; lateral eyes larger; posterior median eyes smaller than anterior median. Legs spined, with brown transverse bands, tibiae I and II with two pairs of ventral spines. Oval dorsum spine, slightly overlapping the posterior regain of cephalothoraxes, dorsal surface with dentate bands beautifully colored with admixture of white, dark brown and red.

Thomisus projectus: –

Nearly pentagonal in shape with a transverse yellow band on the ocular area; narrowing slightly in front, maximum width slightly less than length anterior median eyes slightly smaller than the anterior lateral eyes. Clypeus long, sub rectangular. Legs are long and stout, I and II longer than IV. I pair of legs with three spins above on femur, II legs with a small spot on patella and a black spot sub apically on tibia in front; metatarsi I and II with six pairs of ventral spines; III and IV pair without spot and spines. Pentagonal, slightly overlapping the posterior region in front, broadest at the middle this portion tuberculating laterally with a black spot on the top of tubercle and yellow spot just on inner side of black spot.  

Philodromus Bhagriathai: –

Depressed but cephalic region a little high, wider than long, narrow in front, lateral margins with faint pigmented patches, Clypeus narrow, margin provided with long spine like hairs. Eyes round and black provided with tubercles. Eyes are almost equal in size. Posterior medians separated from each other than from the adjacent laterals. Legs are relatively long, II leg slightly longer than I. Longer than wide, depressed, clothed with fine pubescence, irregular brown dots on the dorsum and lateral sides of the caudal end of the abdomen provided with long contiguous brown patches.

Thomisus pooneus: –

Antero-lateral sides with conspicuous longitudinal black bars. Eyes round, black, anterior row strongly re-curved, anterior median eye slightly larger than posterior medians; ocular area chalk-white. Clypeus long, sub rectangular, margin provided with spine like hairs. Legs are long and stout, I and II longer than III and IV legs, with black or dark brown spots apically bellow on femur and tibiae. Tibiae of I apically with two pairs and metatarsi with six pairs of ventral spines. Round, slightly overlapping the posterior region of cephalothoraxes in front, broadest just behind the middle, laterally n broadest position with muscular tubercles and from this region the posterior portion of abdomen abruptly bent down up the spinnerets. Dorsum on the base with a triangular deep brown marking and similar incomplete transverse bands present on the spinnerets.

Synaema decorata: – 

As long as wide, eyes four pairs, lateral eyes larger, posterior median eye smaller than the anterior median except the posterior median eyes all ringed with chalk-white. Clypeus narrow, margin of clypeus bearing slender spines legs I and II pairs longer than III and IV, tibiae of legs with four pairs of ventral spines, base black, the first pair of spines shortest. Four pairs of circular black spots on the dorsum near the lateral margin, the posterior pair largest.

Tmarus kotigeharus: –

Longer than wide, cephalic region high, clothed with spine; clypeus moderately high, its margin with seven spines directed forward but the middle one is directed upward; sides with broad longitudinal dark brown patches. Eyes round, black both rows re-curved but posterior row longer than anterior, the lateral eyes larger than the others and ringed with brown tubercles; anterior median eyes smaller than posterior medians. Leg I and II much longer than III and IV, clothed hairs and spines; tibiae I and II with three pairs of ventral spines. High and pointed behind, broadest behind the middle, clothed with spines. On the posterior half transversely banded by two dark, incomplete bands.

Tbeilus Simon: – 

Spider is appreciably longer than wide. The change in position of the eyes have gone further than in the genus Thanatus, and eyes of the anterior row, with the posterior median pair, from a small compact hexagonal group of which the posterior laterals conspicuously removed. Abdomen is long and cylindrical or cigar-shaped. Legs relatively long, bearing scapulae on both tarsi and metatarsi. These spiders are found in grass and on bushes; when at rest the legs are stretched out longitudinally, two pairs forward and two pairs backward.

Genus Synaema: –

Greenish in color, as long as wide, cephalic region high, lateral margin encircled by a deep brown line. Eyes black ringed with chalk white tubercles, lateral tubercles contiguous, ocular quad slightly longer than wide, space anterior median eye a little smaller than posterior medians; both rows strongly recurred. Legs are not very strong, I and II pair longer than III and IV, tibia I and II with two pairs of ventral spines. Abdomen light brown, oval, scattered chalk with patches on the dorsum, four pairs of or regular black patches on the posterior half of abdomen arrange in a longitudinal row, the anterior pair larger and posterior pairs smaller, the anterior half provided with black dots; lateral sides with the deep brown patches, ventral surface uniform pale.

Thomisus species	Xysticus minutes
Thomisus projectus	Philodromus Bhagriathai
Thomisus pooneus	Synaema decorata

Tmarus kotigeharus	Tbeilus Simon
Genus Synaema

Conclusion: –

            Though good work has been done in India by Sudhirkumar 2005, a pioneering study was conducted to reveal the spider diversity in Mannavan shola Forest in Kerala state, India. Mannavan shola, the largest Shola patch in Asia, exists in “Western Ghats”, one of the biodiversity hot spots of the world. A total of 72 species of spiders belonging to 57 genera of 20 families were collected from this area during this five-day study. But majority of this work is focused traditional taxonomy of the spiders using morphological characters with little or no emphasis on evolutionary or phylogenetic perspectives. Apart from three volumes of ‘fauna of Indian spider’ and spider of India, no other authoritative books exist on Indian spider. The published literature on Indian spider is poor and not easily available in laboratories. Moreover, most of the literature available on internet does not have open access. Most of the keys for identification are poor and fails to identify immature spider. Hence, it is very much difficult to identify the correct spider species.

             The evolutionary study of the crab spider as not yet attempt in India. The modern trends in systematic such as DNA fingerprinting; sequencing has also not yet tested on the spider from India. The present focus of project on the genetic diversity and evolutionary relationship among intra and inter population of crab spider from Sakri region of Sakri, Dhule District.

References: –

1. Ambalaparambil V. Sudhikumar, Mundackatharappel J. Mathew, Enathayil Sunish, Shourimuthu Murugesan, Pothalil A. Sebastian (2005): Preliminary studies on the spider fauna in Mannavan shoalforest, Kerala, India (Araneae)., Acta zoologica bulgarica, Suppl. No. 1: pp. 319-327.           
2. Koh, L. P. and Wilcove, D. S. (2008): Is oil palm agriculture really destroying tropical

            biodiversity?’, Conservation Letters, 1. pp. 27-33

3. Kujur R and Ekka A (2016): Exploring the Spider fauna of Gomarda Wildlife Sanctuary, Chhattisgarh, India., International Research Journal of Biological Sciences., Vol. 5(6), pp. 31-36.
4. Pawan U. Gajbe (2016): Record of Some Spiders (Arachnida: Araneae) from Karhandla in Nagpur District, Maharashtra., Journal on New Biological Reports., 5(3),  pp.133 – 138.
5. Phalgun Chetia and Dilip Kumar Kalita (2012): Diversity and distribution of spiders from Gibbon Wildlife Sanctuary, Assam, India., Asian Journal of Conservation Biology, Vol. 1 No. 1, pp.5-15.