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Developing effective and long-lasting electrocatalysts for oxygen evolution reaction (OER) is critical for increasing sustainable hydrogen production. This paper describes the production and characterization of CoFeP nanoparticles (CFP NPs) as high-performance electrocatalysts for OER. The CFP NPs were produced using a simple hydrothermal technique followed by phosphorization, yielding an amorphous/crystalline composite structure with improved electrochemical characteristics. Our results reveal that CFP NPs have a surprisingly low overpotential of 284 mV at a current density of 100 mA cm−2, greatly exceeding the precursor CoFe oxide/hydroxide (CFO NPs) and the commercial RuO2 catalyst. Furthermore, CFP NPs demonstrate exceptional stability, retaining a constant performance after 70 h of continuous operation. Post-OER characterization analysis revealed transformations in the catalyst, including the formation of cobalt–iron oxides/oxyhydroxides. Despite these changes, CFP NPs showed superior long-term stability compared to native metal oxides/oxyhydroxides, likely due to enhanced surface roughness and increased active sites. This study proposes a viable strategy for designing low-cost, non-precious metal-based OER catalysts, which will help advance sustainable energy technology. [ABSTRACT FROM AUTHOR]

Water electrolysis is a highly efficient route to produce ideally clean H2 fuel with excellent energy conversion efficiency and high gravimetric energy density, without producing carbon traces, unlike steam methane reforming, and it resolves the issues of environmental contamination via replacing the conventional fossil fuel. Particular importance lies in the advancement of highly effective non-precious catalysts for the oxygen evolution reaction (OER). The electrocatalytic activity of an active catalyst mainly depends on the material conductivity, accessible catalytically active sites, and intrinsic OER reaction kinetics, which can be tuned via introducing N heteroatoms in the catalyst structure. Herein, the efficacious nitrogenation of CuS was accomplished, synthesized using a hydrothermal procedure, and characterized for its electrocatalytic activity towards OER. The nitrogen-doped CuO@CuS (N,CuO@CuS) electrocatalyst exhibited superior OER activity compared to pristine CuS (268 and 602 mV), achieving a low overpotential of 240 and 392 mV at a current density of 10 and 100 mA/cm2, respectively, ascribed to the favorable electronic structural modification triggered by nitrogen incorporation. The N,CuO@CuS also exhibits excellent endurance under varied current rates and a static potential response over 25 h with stability measured at 10 and 100 mA/cm2. [ABSTRACT FROM AUTHOR]

Designing efficient electrocatalytic systems through facile synthesis remains a formidable task. To address this issue, this paper presents the design of a combination material comprising two transition metal oxides (copper oxide and manganese oxide (CuO/MnO2)), synthesized using a conventional microwave technique to efficiently engage as an active oxygen evolution reaction (OER) catalyst. The structural and morphological properties of the composite were confirmed by the aid of X-ray diffraction (XRD) studies, field emission scanning electron microscopy (FESEM), X-ray photoelectron spectroscopy (XPS), and energy-dispersive spectrometry (EDS). FESEM clearly indicated well-aligned interlacing of CuO with MnO2. The OER performance was carried out in 1 M KOH. The assembled CuO/MnO2 delivered a benchmark current density (j = 10 mA cm−2) at a minimal overpotential (η = 294 mV), while pristine CuO required a high η (316 mV). Additionally, the CuO/MnO2 electrocatalyst exhibited stability for more than 15 h. These enhanced electrochemical performances were attributed to the large volume and expanded diameter of the pores, which offer ample surface area for catalytic reactions to boost OER. Furthermore, the rate kinetics of the OER are favored in composite due to low Tafel slope (77 mV/dec) compared to CuO (80 mV/dec). [ABSTRACT FROM AUTHOR]

Sexual selection is a major force influencing the evolution of sexually reproducing species. Environmental factors such as larval density can manipulate adult condition and influence the direction and strength of sexual selection. While most studies on the influence of larval crowding on sexual selection are either correlational or single‐generation manipulations, it is unclear how evolution under chronic larval crowding affects sexual selection. To answer this, we measured the strength of sexual selection on male and female Drosophila melanogaster that had evolved under chronic larval crowding for over 250 generations in the laboratory, along with their controls which had never experienced crowding, in a common garden high‐density environment. We measured selection coefficients on male mating success and sex‐specific reproductive success, as separate estimates allowed dissection of sex‐specific effects. We show that experimental evolution under chronic larval crowding decreases the strength of sexual and fecundity selection in males but not in females, relative to populations experiencing crowding for the first time. The effect of larval crowding in reducing reproductive success is almost twice in females than in males. Our study highlights the importance of studying how evolution in a novel, stressful environment can shape adult fitness in organisms. [ABSTRACT FROM AUTHOR]

Cation-disordered rocksalt (DRX) cathodes have been viewed as next-generation high-energy density materials surpassing conventional layered cathodes for lithium-ion battery (LIB) technology. Utilizing the opportunity of a better cation mixing facility in DRX, we synthesize Na-doped DRX as an efficient electrocatalyst toward oxygen evolution reaction (OER). This novel OER electrocatalyst generates a current density of 10 mA cm−2 at an overpotential (η) of 270 mV, Tafel slope of 67.5 mV dec−1, and long-term stability >5.5 days' superior to benchmark IrO2 (η = 330 mV with Tafel slope = 74.8 mV dec−1). This superior electrochemical behavior is well supported by experiment and sparse Gaussian process potential (SGPP) machine learning-based search for minimum energy structure. Moreover, as oxygen binding energy (OBE) on the surface closely relates to OER activity, our density functional theory (DFT) calculations reveal that Na-doping assists in facile O2 evolution (OBE = 5.45 eV) compared with pristine-DRX (6.51 eV). [ABSTRACT FROM AUTHOR]

Rapid exaggeration of host and pathogen traits via arms race dynamics is one possible outcome of host–pathogen coevolution. However, the exaggerated traits are expected to incur costs in terms of resource investment in other life-history traits. The current study investigated the costs associated with evolved traits in a host–pathogen coevolution system. We used the Drosophila melanogaster (host)–Pseudomonas entomophila (pathogen) system to experimentally derive two selection regimes, one where the host and pathogen both coevolved, and the other, where only the host evolved against a non-evolving pathogen. After 17 generations of selection, we found that hosts from both selected populations had better post-infection survivorship than controls. Even though the coevolving populations tended to have better survivorship post-infection, we found no clear evidence that the two selection regimes were significantly different from each other. There was weak evidence for the coevolving pathogens being more virulent than the ancestral pathogen. We found no major cost of increased post-infection survivorship. The costs were not different between the coevolving hosts and the hosts evolving against a non-evolving pathogen. We found no evolved costs in the coevolving pathogens. Thus, our results suggest that increased host immunity and pathogen virulence may not be costly. [ABSTRACT FROM AUTHOR]

Vehicle number plate recognition technique is used for extracting an area of number plate from captured vehicle image. We use this technique because as we know there is highly increase in number of vehicles all over the world and it keeps increasing. So for the purpose of law enforcement and traffic management it become difficult to track each and every single vehicle so to overcome this, we need this type of technique. This system is very helpful for traffic police in order to find the details of a vehicle violating the traffic rules. This technique is used for various applications such as automatic toll collection, Border crossings, parking system, Traffic control, stolen cars tracking etc. The technique used in this paper is a histogram based approach which has advantage of simple and fast response as compare to other techniques. In this paper we use various algorithms from distinct edge detection to region of interest extraction. [ABSTRACT FROM AUTHOR]

For efficient water splitting, it is essential to develop inexpensive and super-efficient electrocatalysts for the oxygen evolution reaction (OER). Herein, we report a phosphate-based electrocatalyst [Fe3Co(PO4)4@reduced-graphene-oxide(rGO)] showing outstanding OER performance (much higher than state-of-the-art Ir/C catalysts), the design of which was aided by first-principles calculations. This electrocatalyst displays low overpotential (237 mV at high current density 100 mA cm−2 in 1 M KOH), high turnover frequency (TOF: 0.54 s−1), high Faradaic efficiency (98%), and long-term durability. Its remarkable performance is ascribed to the optimal free energy for OER at Fe sites and efficient mass/charge transfer. When a Fe3Co(PO4)4@rGO anodic electrode is integrated with a Pt/C cathodic electrode, the electrolyzer requires only 1.45 V to achieve 10 mA cm−2 for whole water splitting in 1 M KOH (1.39 V in 6 M KOH), which is much smaller than commercial Ir-C//Pt-C electrocatalysts. This cost-effective powerful oxygen production material with carbon-supporting substrates offers great promise for water splitting. The sluggish kinetics of the oxygen evolution reaction (OER) is the main obstacle in water splitting which is generally catalyzed by precious metals. Here, authors report a DFT predicted non-precious bimetallic phosphate electrocatalyst that displays high OER activity and stability. [ABSTRACT FROM AUTHOR]

We report a highly efficient and cost-effective binder-free catalyst for the hydrogen evolution reaction (HER) using V2O5 particles on nickel foam (NF) (V2O5/Ni(OH)2@NF). This low-cost catalyst exhibits Pt-like activity with a low overpotential of 39 mV at 10 mA cm−2 (lowest among V-based materials which are known to be generally non-explosive and safe) and long-term stability in a 1 M KOH solution. The overall performance is highly comparable to that of a commercial 20% Pt/C catalyst on NF. Furthermore, the V2O5/Ni(OH)2@NF outperforms the Pt/C catalyst at a higher current density (100 mA cm−2) which is more preferable for industrial applications. First principles calculations show that the remarkable HER activity is ascribed to the near-zero adsorption free energy (ΔGH*) on the Ni-site of Ni(OH)2@NF and the Ni- and O-sites of in situ generated V2O5@NF, due to the charge transfer arising from adsorbed O atoms on Ni(111), along with high conductivity of NF. O-adsorption on the Ni transition metal surface downshifts the d-band center of the transition metal, which helps in quick hydrogen desorption by weakening the hydrogen binding strength. As a result, most Ni fcc sites of V2O5/Ni(OH)2@NF are more active than pristine Ni fcc sites. The V2O5/Ni(OH)2@NF catalyst initiates overall water splitting at 1.53 V in a 6 M KOH solution for solar-to-hydrogen generation in a two-electrode set-up using a solar panel. [ABSTRACT FROM AUTHOR]