Time-Dependent Quantum Wave Packet Calculation for Reaction S-(^(2)P)+H_(2)(^(1)∑_(g)^(+))→SH-(^(1)∑)+H(^(2)S) on Ab Initio Potential Energy Surface

The time-dependent wave packet propagation method was applied to investigate the dynamic behaviours of the reaction S-(^(2)P)+H_(2)(^(1)∑_(g)^(+))→SH-(^(1)∑)+H(^(2)S)based on the electronic ground state(^(2)A′)potential energy surface of the SH_(2)-ionic molecule.The collision energy dependent reaction probabilities and integral cross sections are obtained.The numerical results suggest that there are significant oscillation structures over all the studied range of the collision energies.The vibrational excitation and rotational excitation of the diatomic reagent H_(2) promote the reactivity significantly as suggested by the numerical total reaction probabilities with the initial rotational quantum number of j=0,2,4,6,8,10,and the vibrational quantum number v=0,1,2,3,4.The numerical integral cross sections are quite consistent with the experimental data reported in previous work.

Fast charge transfer kinetics in Sv-ZnIn_(2)S_(4)/Sb_(2)S_(3)S-scheme heterojunction photocatalyst for enhanced photocatalytic hydrogen evolution

Constructing a S-scheme heterojunction with tight interface contact and fast charge transfer is beneficial to improving the photocatalytic hydrogen evolution performance.Herein,a unique one-dimensional(1D)/two-dimensional(2D)S-scheme heterojunction containing 1D Sb_(2)S_(3) nanorods and 2D ZnIn_(2)S_(4) with affluent sulfur vacancies(denoted as Sv-ZnIn_(2)S_(4)@Sb_(2)S_(3)) was designed.The introduced sulfur vacancy can promote the effective adsorption of H+for the following interfacial hydrogen-evolution reaction.Furthermore,the larger contact area and stronger electron interaction between Sb_(2)S_(3) and ZnIn_(2)S_(4) effectively inhibits the recombination of photo-generated electron–hole pairs and abridges the migration distance of charges.As a result,the optimal Sv-ZnIn_(2)S_(4)@Sb_(2)S_(3) sample achieves H_(2) evolution activity of 2741.3 mol·h^(−1)·g^(−1),which is 8.6 times that of pristine ZnIn_(2)S_(4) and 3.0 times that of the Sv-ZnIn_(2)S_(4) samples.Based on the experimental result,the photo-reactivity S-scheme mechanism of hydrogen evolution from water splitting with Sv-ZnIn_(2)S_(4)@Sb_(2)S_(3) is proposed.This work provides an effective method for developing S-scheme heterojunction composites of transition metal sulfide with high hydrogen evolution performance.

Amino acid compounds released by the giant freshwater prawn Macrobrachium rosenbergii during ecdysis:a factor attracting cannibalistic behaviour?

Ecdysis is a comm on phe nomenon that happe ns throughout the life phase of the giant freshwater prawn Macrobrachium rosenbergii.It is vital to better understand the correlation between cannibalism and biochemical compound that exists during the moulting process.The objective of the present study was to determine the amino acid profile released by M.rosenbergii during the ecdysis process that promotes cannibalism.To accomplish this,changes in amino acid levels(total amino acid(TAA)and free amino acid(FAA))of tissue muscle,exoskeleton,and sample water of culture medium from the moulting(E-stage)and non-moulting(C-stage)prawns were analysed using highperformanee liquid chromatography(HPLC).Comparison study revealed that among the TAA compounds,proline and sarcosine of tissues from moulting prawn were found at the highest levels.The level of FAA from water that contains moulting prawns(E-stage)was dominated by tryptophan and proline.Significant values obtained in the present study suggested that these amino acid compounds act as a chemical cue to promote cannibalism in M.rosenbergii during ecdysis.The knowledge of compositions and compounds that were released during the moulting process should be helpful for better understanding of the mechanism and chemical cues that play roles on triggering cannibalism,and also for future dietary man ipulati on to improve feeding efficie ncies and feeding man agement,which in directly impacts productivity and profitability.

An Integrated Study for the Utilization of Anthraquinone Compounds Extract“Heshouwu”In vivo and their Comparative Metabolism in Liver Microsomes Using UPLC-ESI-Q-TOF/MS^(n)

Objective: Anthraquinone(AQ), a major bioactive component of the traditional Chinese medicine He ShouW u, has widespread applications in industry and medicine. The objective of the current study is to explore the differences in the bioavailability of anthraquinones in vivo and the metabolism in liver microsomes. Materials and Methods: In vivo, we used a reliable UPLC?ESI?Qq Q?MS/MS method to measure seven AQ compounds in the jugular vein plasma of rats following oral administration of He Shou Wu. Furthermore, in order to quantify the bioavailability of AQs in vivo and to further understand the metabolism of these compounds, we compared the in vitro metabolism of AQ in different species with respect to metabolic profiles, the enzymes involved, and catalytic efficiency using liver microsomes from human(HLM), mouse(MLM), rat(RLM), and beagle dog(DLM). Results: We identified two metabolic pathways, including the hydroxylation and glucuronidation of AQ, in the liver microsomes of humans and other species using UPLC?ESI?Q?TOF. We found that substitutions on the AQ ring were crucial to the activity and regioselectivity of its hydroxylation. In general, hydroxylation activity decreased greatly with β?COOH(rhein) and enhanced dramatically with β?OH(emodin). We also found that glucuronidation of the compound emodin?8?O?β?D?glucoside acts as the main isoform in AQ hydroxylation in HLM and DLM. Total microsomal intrinsic clearance values for AQ were greatest in mouse microsomes, followed by those in dog, human, and rat microsomes. Conclusion: The absorption of different anthrquinone compounds varied based on the compound structure, the metabolism types and products of anthraquinones in liver microsomes were different in different species. These findings provide vital information for a deeper unuunderstanding of the metabolism of AQs.