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Hydrogen production using novel catalysts is regarded as one of the most needed technology for the future economic needs and water splitting to give H _2 gas, which is a challenging task for large-scale production. This work reports the synthesis of Meso-Cu-BTC metal organic framework and further used for understanding its role in electrochemical hydrogen evolution reaction (HER) in 1 M NaOH solution. Meso-Cu-BTC electrocatalyst showed a less overpotential of 89.32 mV and an onset potential of 25 mV with an appreciable current density. Results show a low Tafel slope of 33.41 mVdec ^−1 and long-term durability. Thus, the overall results show that Meso-Cu-BTC acted as a good candidate for electrocatalysis towards hydrogen evolution.

This article reports microstructural, morphological, optical, and photoresponse characteristics of pure and zirconium-doped V2O5 nanorods (Zr:V2O5; Zr at. 1, 3, 5, and 7 wt%) that were synthesized via the wet precipitation method. Undoubtedly, under experimental conditions, a growth mechanism has been proposed which explains morphological evolution. The microstructural analysis confirmed that the prepared samples showed a broad peak consistent with the V2O5 orthorhombic structure, and the absences of other reflections in this pattern ensure the phase purity. The optimized average crystallite size is determined by using Scherrer's equation from the most influential (002) peak of diffraction, which has coincided with those calculated by the TEM micrograph. SEM images showed agglomerated particles on the surfaces owing to an increase in the Zr-doping levels. The outcomes of Raman and XPS indicate that Zr doping can facilitate the generation of V5+ and oxygen vacancy. The recorded UV-DRS spectra reveal the redshifts, and the estimated optical bandgap (Eg) was decreasing with increasing Zr amount, which is further confirmed by PL studies. We used the nebulizer spray technique, a cost-effective, sophisticated, and effective way to formulate an n-ZrxV2O5/p-Si photodetector. The formulated n-ZrxV2O5/p-Si photodetector has good photoconducting behavior. [ABSTRACT FROM AUTHOR]

In the present work, Nickel doped Molybdenum trioxide (NixMoO3) where Ni = X (X = 5, 10, and 15%) nanoparticles (NPs) were synthesized by a wet chemical method. These nano crystals are structurely analysized by X-ray diffraction and confirm the formation of orthorhombic structure in both MoO3 and Ni-doped MoO3 samples. The impact of Ni doping on crystallite size, micro strain, and texture co efficient are obtained from XRD pattern. The morphology studies of FE-SEM and HR-TEM show that the presence of one dimensional (1D) nanorods with an average diameter of particle size around 28–32 nm and the compositional stoichiometry is confirmed by EDAX technique. The functional group and the vibrational mode of metal oxide (Mo = O) are confirmed by FT-IR spectra. The photocatalytic activities of pure and Ni-doped MoO3 are attributed to the degradation efficiency under UV–Visible light irradiation. The result shows that these structure exhibits promising degradation of Methylene blue (MB) is calculated along with the kinetic study, cyclic efficiency, and growth mechanism. The ability of the catalysts generates electron-hole pairs which create free radicals and also help to undergo the secondary reactions. The MoO3 and Ni-doped MoO3 samples normally reveal better results against in antibacterial activity such as Escherichia Coli (E. Coli) and Staphylococcus aureus (S. aureus) bacteria. Overall, the results demonstrate that the doping of Ni2+ ions inside the MoO3 matrix enhances the performance in antibacterial activity. Highlights: Ni decorated MoO3 nanorods of various concentrations (5, 10 & 15%) have been investigated. Morphological, structural & optical properties of Ni incorporation of MoO3 nanorods are studied by various experimental parameters. Degradation rate constant is found through the pseudo-first-order kinetic model. Recycle test and photocatalytic mechanisim are studied under UV-Visible light irradiation. The bacteria strain observes through disc diffusion technique. [ABSTRACT FROM AUTHOR]

This paper studies earnings management using 363 closed-end mutual fund firm-years of data. Closed-end fund assets consist of unrestricted and restricted securities, and realized and unrealized income. While unrestricted securities are not subject to earnings management, restricted security values are largely discretionary. Managerial valuation of restricted securities is modeled as contingent on unrestricted returns relative to a performance benchmark. Four unrestricted performance regions are identified. Known multi-period compensation incentives become the basis for hypothesizing earnings management behaviors in the regions in the form of restricted security valuation. Across several benchmarks, the results are consistent with multi-period maximization rather than simpler single-period compensation maximization or income smoothing. Funds with extreme unrestricted performance show relatively larger income-decreasing earnings management, and funds with slightly-below benchmark returns show relatively larger income-increasing earnings management than those slightly above. These results clarify the relationship between complex earnings management behavior and managerial incentives. [ABSTRACT FROM AUTHOR]

Manganese oxide (Mn2O3) nanoparticles have been synthesized in co-precipitation method and followed by annealing of the samples at 200°C, 400°C and 600°C at 10 hours. The prepared samples are characterized with X-ray diffraction (XRD), scanning electron microscopy (SEM), energy dispersive analysis of X-ray spectroscopy (EDAX), UV-visible spectroscopy and vibrating-sample magnetometer (VSM). The XRD spectra reveals that the body centred cubic structure of Mn2O3 powder was obtained. Annealing temperature proliferates the crystallite sizes from 31 to 81nm are calculated by Scherer's formula. The SEM image unveils that the materials have an irregular nano-stick like morphology. Optical properties are appraised by UV-visible spectroscopy; band gap values deceased with increasing annealing treatment. Low annealing temperature treatment sample shows high transmittance in visible region. FT-IR studies shows that the number of surface hydroxyl group dwindle with the enhance of annealing temperature. The magnetization (VSM) is conducted to the sample and the saturation magnetization (Ms) is 38.73emu/g. [ABSTRACT FROM AUTHOR]

A group-set of male Fischer 344 rats was kept on a choline-devoid (CD) diet for 3, 6, 9, 12 or 16 months. A second set was fed the same diet for 3, 6 and 9 months, followed by a control, choline-supplemented diet for 3 months. A third set was fed the CD diet for 0, 3, 6, 9 and 12 months and the control diet for the duration (16 months) of the experiment. [H]Thymidine was injected into some of the animals to assess the extent of liver cell proliferation. In the latter animals, liver triacylglycerols were also determined as an index of the hepatonecrogenic action of a CD diet. Foci of enzyme-altered hepatocytes were detected histochemically and the presence of tumors was established histologically. Cell proliferation and triacylglycerols were both high after 3 months and declined steadily as the length of CD diet feeding increased. Upon subsequent feeding with the control diet, triacylglycerols promptly cleared from the liver, while cell proliferation remained at reduced but still relatively high levels for at least 3 months. Increasing but small numbers of foci of enzyme-altered hepatocytes were detected in some of the rats under experimentation for 6 months or longer. The incidence of hepatocellular carcinomas was 13, 27, 33 and 73% respectively in rats fed the CD diet for 3, 6, 9 or 12 months and the control diet for the duration of the experiment. On the other hand, only 26% of the rats fed exclusively the CD diet for 16 months developed carcinomas. The results were taken as evidence that: (i) liver cell proliferation persists beyond discontinuation of a CD diet; (ii) the liver contains initiated cells—capable of full evolution to cancer even in the absence of active promotion—after a relatively short 3-month exposure to a CD diet; and (iii) occurrence of a late event(s) is critical for the genesis of the tumors. Whether a CD diet is a complete carcinogen able to initiate liver cells or acts merely as a promoter of the evolution of endogenous initiated cells is briefly discussed. [ABSTRACT FROM PUBLISHER]

Liver DNA was labeled in a group of weanling Fischer-344 male rats by placing mini-osmotic pumps, loaded with [methyl-H]thymidine, under the dorsal skin for 14 days. The animals were then placed on either a cholinesupplemented or a choline-devoid diet, and subgroups on each diet were killed after 1, 2, 4, 8 and 16 weeks. Liver DNA total and specific radioactivities were determined in all rats. The results were used to estimate the half-life (½) of liver cells, and the fractional rates of liver cell death ( and proliferation (). In rats fed the control choline-supplemented diet, liver cells were estimated to die at an overall d of 0.16% per day, and to have a t, h of 439.5 days; was higher in younger than in older rats. In rats fed the choline-devoid diet, liver cells died at a ranging from 4.82 down to 0.93% per day, as the length of the feeding period increased; corresponding ½ were 14.3 and 74.6 days. In these rats, was more than sufficient to compensate for cell loss. The results show that liver-cell death represents a major consequence of feeding a choline-devoid diet to rats, and that the necrogenic action of the diet is a major factor responsible for the highly increased turnover of liver cells present in these animals. However, evidence was obtained that the diet has also a primary mitogenic action, beyond those related to replacement of dead cells, and to cell accretion due to normal growth of the animals and the liver. [ABSTRACT FROM PUBLISHER]

Groups of rats were fed for 1, 4 or 7 months choline-devoid or choline-supplemented diets, that provided ∼50% of the methionine, and 0.15% or 150% of the choline requirements of young, growing rats. liver DNA was isolated and analyzed by the nuclease Pl-enhanced version of the P-postlabeling assay, which detects aromatk/hydrophobic DNA adducts and I-compounds (adduct-like DNA modifications shown to accumulate in tissues of aging rats). DNA adducts and qualitative differences in the patterns of I-compounds were not observed in rats fed the two diets. However, in rats fed the choline-devoid diet there was a drastic reduction in the accumulation of I-compounds, compared with that in rats fed the control diet. These results extend previous evidence of a lack of relevant DNA adducts in the liver of rats fed the choline-devoid diet, and suggest the possibility of a role of I-compounds in the carcinogenicity of this diet. [ABSTRACT FROM PUBLISHER]