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Indirect electrocatalytic conversion of cheap organic raw materials via the activation of S─H and N─H bonds into the value-added S─N/S─S bonds chemicals for industrial rubber production is a promising strategy to realize the atomic economic reaction, during which the kinetic inhibition that is associated with the electron transfer at the electrode/electrolyte interface in traditional direct electrocatalysis can be eliminated to achieve higher performance. In this work, a series of di-copper-substituted phosphotungstatebased foams (PW 10 Cu 2 @CMC) are fabricated with tunable loadings (17 to 44 wt%), which can be successfully applied in indirect electrocatalytic syntheses of sulfenamides and disulfides. Specifically, the optimal PW 10 Cu 2 @CMC (44 wt%) exhibits excellent electrocatalytic performance for the construction of S─N/S─S bonds (yields up to 99%) coupling with the efficient production of H 2 (≈50 µmol g -1  h -1 ). Remarkably, it enables the scale-up production (≈14.4 g in a batch experiment) and the obtained products can serve as rubber vulcanization accelerators with superior properties to traditional industrial rubber additives in real industrial processes. This powerful catalysis system that can simultaneously produce rubber vulcanization accelerator and H 2 may inaugurate a new electrocatalytic avenue to explore polyoxometalate-based foam catalysts in electrocatalysis field., (© 2023 Wiley-VCH GmbH.)

This paper reports the energies and charge and spin distributions of the mono-substituted N defects, N 0 , N s , N + and N s -H in diamonds from direct Δ-SCF calculations based on Gaussian orbitals within the B3LYP function. These predict that (i) N - , N s and N s all absorb in the region of the strong optical absorption at 270 nm (4.59 eV) reported by Khan et al., with the individual contributions dependent on the experimental conditions; (ii) N s -H, or some other impurity, is responsible for the weak optical peak at 360 nm (3.44 eV); and that N 0 is the source of the 520 nm (2.38 eV) absorption. All excitations below the absorption edge of the diamond host are predicted to be excitonic, with substantial re-distributions of charge and spin. The present calculations support the suggestion by Jones et al. that N s contributes to, and in the absence of N + is responsible for, the 4.59 eV optical absorption in N-doped diamonds. The semi-conductivity of the N-doped diamond is predicted to rise from a spin-flip thermal excitation of a CN hybrid orbital of the donor band resulting from multiple in-elastic phonon scattering. Calculations of the self-trapped exciton in the vicinity of N s indicate that it is essentially a local defect consisting of an N and four nn C atoms, and that beyond these the host lattice is essential a pristine diamond as predicted by Ferrari et al. from the calculated EPR hyperfine constants.- all absorb in the region of the strong optical absorption at 270 nm (4.59 eV) reported by Khan et al., with the individual contributions dependent on the experimental conditions; (ii) N s -H, or some other impurity, is responsible for the weak optical peak at 360 nm (3.44 eV); and that N s + is the source of the 520 nm (2.38 eV) absorption. All excitations below the absorption edge of the diamond host are predicted to be excitonic, with substantial re-distributions of charge and spin. The present calculations support the suggestion by Jones et al. that N s + contributes to, and in the absence of N s 0 is responsible for, the 4.59 eV optical absorption in N-doped diamonds. The semi-conductivity of the N-doped diamond is predicted to rise from a spin-flip thermal excitation of a CN hybrid orbital of the donor band resulting from multiple in-elastic phonon scattering. Calculations of the self-trapped exciton in the vicinity of N s 0 indicate that it is essentially a local defect consisting of an N and four nn C atoms, and that beyond these the host lattice is essential a pristine diamond as predicted by Ferrari et al. from the calculated EPR hyperfine constants.

In order to improve the photocatalytic properties of P25, using urea, thiourea and methionine as modifiers, the modified catalysts N-P25, S-P25 and N,S-P25 with visible light catalytic activity are prepared by grinding-calcination method, respectively. The properties of modified photocatalysts are characterized by scanning electron microscopy (SEM) and UV-Vis absorption spectroscopy, and the degradation property of acid red B in visible light by the modified photocatalysts is investigated. The results show that the wavelength ranges of light response of the N-P25, S-P25 and N,S-P25 modified photocatalysts expands, intensive absorption appears in both ultraviolet and visible light regions; the N,S-P25 prepared under the condition of calcination temperature of 700 ℃ and calcination time of 20 h has the highest catalytic activity on the degradation of acid red B, and the degradation reaction of acid red B in visible light conforms to the apparent first order reaction kinetics. The study proves that the modified P25 catalyst can improve the photocatalytic degradation of acid red B under visible light conditions, and enriches the research ideas of photocatalytic degradation of dye wastewater in visible light.

Abstract Canine vector-borne infections (CVBIs) are a global health problem. The military working dogs of Sri Lanka die at an early age, and CVBIs have been a leading speculated cause. We examined CVBIs in the working dogs of the Sri Lanka air force (SLAF) and free-roaming dogs (FRDs) and privately owned dogs (PODs) country-wide. Giemsa-stained smears were prepared and conventional PCR-positive DNA was subjected to sequencing and phylogeny. Of the 668 dogs sampled, 212 (31.7%) had one or more CVBIs. The prevalence of infections among the FRDs (40.0%) was significantly higher than SLAF working dogs (30.0%; χ2 = 10.5216; p = 0.0012) and PODs (26.2%; χ2 = 5.3414, p = 0.0208) but not between SLAF dogs and PODs (χ2 = 1.7655, p = 0.1838). Many infected dogs were asymptomatic (57.4%), which was higher among the FRDs. Seven infectious agents were identified: Babesia gibsoni, B. canis, Ehrlichia canis, Anaplasma platys, Leishmania sp., Hepatozoon canis, and filaria worms. The most common infection was B. gibsoni (13.8%), followed by E. canis (9.9%). Three tick species: Rhipicephalus linneai, Rhipicephalus haemaphysaloides and Haemophysalis bispinosa were found infesting the dogs. The SLAF dogs were thoroughly quarantined upon arrival, but the infection prevalence was similar to PODs.

We study the set of periods of the Morse-Smale diffeomorphisms on the n -dimensional sphere S n , on products of two spheres of arbitrary dimension S m × S n with m ≠ n , on the n -dimensional complex projective space C P n and on the n -dimensional quaternion projective space H P n . We classify the minimal sets of Lefschetz periods for such Morse-Smale diffeomorphisms. This characterization is done using the induced maps on the homology. The main tool used is the Lefschetz zeta function., (© The Author(s) 2021, corrected publication 2024.)

With unique chemical reactivity, α‐oxoketene S,S‐ and N,S‐acetals have attracted enormous attention in the past decades, whereas limited reports exist for their synthesis via eco‐compatible protocols. Herein, we developed a one‐pot protocol for symmetrical and unsymmetrical α‐oxoketene S,S‐/N,S‐acetals through chemoselective alkylation of α‐enolic dithioesters using Mitsunobu chemistry at room temperature. The operationally simple and user‐friendly mild protocol tolerates a wide range of alcohols and α‐enolic dithioesters/β‐ketothioamides. Short reaction time, good yields, highly selective C−S functionalization, and E/Z‐stereoselectivity are imperative characteristics of this strategy. [ABSTRACT FROM AUTHOR]

Introduction: The development of technology in the arena of organ transplantation bloomed during 1980s in India. In later years, there was a shortage of organs as the rate of cadaver donation was quite low; therefore, this led to unethical and coerced practice in organ transplantation. The socioeconomic group that was most impacted by these activities consisted of individuals in dire need of funds and were prepared to trade with important organs in return for money. Methods: The study adopts a desk-based methodology, categorized into primary and secondary data. The primary data consist of analysis of the Transplantation of Human Organs and Tissues Act (THOTA), 1994 read with 2011 Amendment and 2014 Rules. Further various orders and resolutions of the Government of India, and committees constituted by the Center as well as Hon’ble High Court were analyzed. The Secondary data included analysis of parliamentary questions, and numerous judgments of Hon’ble Supreme Court of India and various High Courts across the country. Results: Various provisions of THOTA, 1994 should be re-examined. Due to rampant poverty, illicit organ trafficking is on a rise, with women targeted the most for kidneys, thus impacting the social structure of the society. The most trafficked organ among the liver, lungs, kidney, and heart is kidney. Conclusion: There is a dire need for health legislations with provisions to increase the donor pool. It is recommended that in addition to using the cadaver organ pool through road deaths and brain-dead victims, we should transition to both the presumed consent and opt-out method of permission and creating awareness of the donation of organs among the general public.