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The primary objective of this study is to conduct a thorough examination of relativistic structures within the framework of f(ℛ,풯 ) gravity, where ℛ is the Ricci scalar and 풯 is the trace of the energy–momentum tensor. We investigate the emerging characteristics of compact stars, focusing on the ℛ + 2ξ풯 model, where ξ is the coupling constant. In the initial sections of the paper, we concentrate on the examination of exact interior solutions involving perfect fluid. With this aim, we introduce the metric coefficient L = S(1 + 2ar2)d/2, where a and S are arbitrary constants to be computed from the matching conditions and d is a positive odd integer. It is worth noticing that we select a group of 10 significant compact stars from recent studies, namely, Vela X − 1, EXO 1785 − 248, 4U1820 − 30, SMCX − 4, HerX − 1, PSR J1614 − 2230, PSRJ1903 + 327, CenX − 3, 4U1538 − 52 and LMCX − 4. To investigate the viability of our model, we conduct various checks, including the analysis of energy density and pressure components, equilibrium, and energy conditions, stability analysis and the adiabatic index. An important part of this work provides the slowly rotating property of stars, accompanied by the derivation of the moment of inertia. The relationship of mass, energy density, radius and moment of inertia for stellar objects are observed. Our findings demonstrate that obtained results are physically acceptable and consistent with our considered model. [ABSTRACT FROM AUTHOR]

Synthesis of mixed transition metal nitrides often leads to the formation of more than one phases in the final product. A control over molar ratio of metals (Fe:Ni) along with synthetic strategy is used to form phase pure product (Fe 3 Ni 7 N@C). The synthesized material is used as an efficient and cost-effective electrocatalyst for oxygen evolution reaction (OER). Fe 3 Ni 7 N@C requires a low overpotential of 290 mV to achieve a catalytic current density of 10 mA cm−2 which holds Tafel slope of 40 mV dec−1 superior to the noble metal benchmark catalysts. The physicochemical integrity of Fe 3 Ni 7 N@C is maintained up to 12 h activity as evident from post catalytic characterization. Fe3Ni7N@C nanoparticles for oxygen evolution reaction. [Display omitted] • A control over molar ratio of metals (Fe:Ni) is used to form phase pure product (Fe 0.3 Ni 0.7 N@C). • Fe 0.3 Ni 0.7 N@C is used as an efficient electrocatalyst for oxygen evolution reaction (OER). • Fe 0.3 Ni 0.7 N@C requires a low overpotential of 290 mV to achieve a catalytic current density of 10 mA cm−2. • The physicochemical integrity of Fe 0.3 Ni 0.7 N@C is maintained up to 12 h activity. [ABSTRACT FROM AUTHOR]

Transition metal oxyhydroxides have been used as promising electrocatalysts for water splitting however, their catalytic activity is restricted due to low surface area and poor conductivity. Herein, we report novel composite FeOOH@ZIF-12/graphene composite as electrocatalyst for water oxidation, whereby ZIF-12 provide extra surface for the FeOOH dispersion whilst graphene act as excellent electron mediator. The composite shows a low overpotential value of 291 mV to attain a current density of 10 mA cm−2 and a low Tafel slope value of 78 mV dec−1. The catalyst offers a maximum current density of 101 mA cm−2, while it gives a turnover frequency (TOF) value of 0.031 s−1 at an overpotential of 291 mV only. The excellent activity and remarkable stability of composite is attributed to highly conductive and porous support. [Display omitted] • FeOOH nanoparticles are incorporated in ZIF-12/graphene matrix. • The synthesized composite is utilized as electrocatalyst for water oxidation. • The composite shows a low overpotential value of 291 mV @ 10 mA cm−2. • The catalyst offers a maximum current density of 101 mA cm−2 with a TOF value of 0.031 s−1. [ABSTRACT FROM AUTHOR]

Abstract The development of efficient and cost-effective electrocatalysts for oxygen evolution reaction is a priority research area. Metal-organic frameworks (MOFs) have recently captured attention as heterogeneous water oxidation catalysts. In spite of their robustness and stability under specific pH conditions, the relatively low current density achieved is their main drawback. Herein, we explored a cobalt based framework [Co(bpy)(fa)] n (DMF) 0.25 (bpy) 0.25 (1) {bpy = 4,4ʹ-bipyridine, fa = fumarate, DMF = dimethylformamide} as an efficient electrocatalyst for the water oxidation reaction. Compound 1 exhibits excellent activity in a neutral phosphate buffer solution. Chronoamperometric studies show that 1 offers a current density of 10 mA cm−2 at only η = 382 mV. Onset over-potential of 248 mV is observed which holds a Tafel slope value of 84 mV dec−1. The catalyst showed a turnover frequency (TOF) of 2 × 10−3 s−1 for oxygen evolution reaction (OER) at 289 mV. Detailed electrochemical studies, including long-term electrolysis, indicates the potential of compound 1 to be utilized as heterogeneous catalyst toward the oxygen evolution reaction. [ABSTRACT FROM AUTHOR]

• Mn-derived compounds are promising electrocatalyst. • Post-synthetic modification of Mn-based materials, proved to be effective for HER. • Kinetic & thermodynamics improved by synthesizing polymetallic Mn-based compounds. Green hydrogen production driven by electrocatalysis is a good substitute for carbon-based fuels and may offer a sustainable way of producing renewable energy. Although Pt-based catalysts have been used for water reduction studies, they suffer from scarcity and high cost. Among earth-abundant transition metals, manganese is an attractive option for the manufacture of robust and efficient water reduction catalysts owing to its peculiar electrochemical properties. In this succinct perspective, we will delineate the synthesis approaches of Mn-based catalysts conjoining fundamentals of the HER process, and then we will review the Mn-based promoters. In the penultimate section, we will explore how the morphology, composition and structure of the catalyst influence the HER performance. Lastly, challenges and future perspectives will be featured. [ABSTRACT FROM AUTHOR]

Objective: Globally millions of people working in various industries and are exposed to different toxins which may affect their genetic stability and DNA integrity. Present study was designed to estimate the expression variation of genes related to DNA repair (XRCC1, PARP1) and lead toxicity (ALAD) in exposed industrial workers. Methods: About 200 blood samples were collected from workers of brick kiln, welding, furniture and paint industry (50/industry) along with age and gender matched controls. mRNA expression of genes was measured using RT-PCR. Serum levels of total ROS, POD, TBAR activity was calculated. Blood lead levels were estimated by atomic absorption spectrometer. Results: Relative expression of XRCC1 and PARP1 gene was significantly (P < 0.001) upregulated, while ALAD gene expression was downregulated in exposed group compared to control. Expression of XRCC1 and PARP1 was increased (P < 0.001) in exposed workers with > 30 year age compared to control with > 30 year age. Same was observed when < 30 year age group of control and exposed was compared. Likewise, XRCC1 and PARP1 expression was increased (P < 0.001) in exposed workers with > 30 year age compared to workers with < 30 year age. Whereas, ALAD gene showed significant (P < 0.01) decrease in > 30 year age workers compared to control of same age and exposed with < 30 year of age. Relative expression of XRCC1 and PARP1 was increased (P < 0.001) in exposed smokers compared to exposed non-smokers and control smokers. Whereas, ALAD gene expression reduced (P < 0.001) significantly in both groups. Blood lead content was higher (P < 0.001) in exposed group compared to control. Strong correlation was observed between XRCC1, PARP1 and ALAD gene versus age, total exposure duration, exposure per day and lead deposition. ROS, TBARS and POD activity was higher (P < 0.01) in exposed group compared to control group. Conclusion: Present study suggested deregulation of genes related to DNA repair and lead intoxication in exposed group compared to controls. Strong correlation was observed between selected genes and demographic parameters. Present results revealed altered activity of oxidative stress markers which would induce oxidative damage to DNA integrity and limit the function of repair enzymes. [ABSTRACT FROM AUTHOR]

[Display omitted] • Transition metal nitrides (TMNs) have gained substantial interest to catalyse water splitting reaction. • Iron and nickel based TMNs are considered as ideal electrocatalysts because of the abundance, low cost, and high catalytic activity. • Single phase TMNs have unsatisfactory performance due to inadequate M−H/M−OH bond strength. • Recent developments pertaining to Fe and Ni-based TMNs are presented for electrochemical water splitting. Transition metal nitrides (TMNs) have gained substantial interest to generate hydrogen from direct dissociation of water via catalytic strategy. Due to the unique noble metal like structure, high electric conductivity, corrosion resistance, broad pH stability and probable structural modifications TMNs are gauged as efficient hydrogen evolution reaction (HER), oxygen evolution reaction (OER) and overall water splitting (OWS) electrocatalysts. Iron and nickel based TMNs are considered as ideal electrocatalysts because of the abundance, low cost and high catalytic activity as compared to the expensive benchmark catalysts. However, the single phase TMNs have unsatisfactory performance due to inadequate M−H/M−OH bond strength. Most researchers have focused in designing advanced heterostructures by doping other metals, metallic compounds, and conductive substrates to improve catalytic performance due to the tailored electronic structure to modify M−H/M−OH bond strength, boost electrochemical stability and synergistic effects. In this review, we highlight the recent developments pertaining to Fe and Ni-based TMNs from the stance of advanced nanoarchitecture electrocatalysts for electrochemical water splitting. The key challenges and future perspectives confronting expansion of water splitting catalysts are critiqued. [ABSTRACT FROM AUTHOR]