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[Objective] Characterized by its abundant sources, green and low-carbon nature, and wide-ranging applications, hydrogen energy has become a significant strategic choice for accelerating energy transformation and upgrading, fostering new economic growth points, and achieving carbon neutrality goals. The hydrogen energy industry chain encompasses the production, storage, transportation, and utilization of hydrogen, with its storage and transportation being a crucial link connecting the upstream and downstream sectors of the chain. Hydrogen can be stored and transported in high-pressure gaseous, low-temperature liquid, and solid states. Among these, high-pressure gaseous storage and transportation have become dominant due to several advantages, including simple equipment structure, low cost, and high technological maturity. However, metallic materials used in hydrogen storage and transport equipment may suffer from high-pressure hydrogen embrittlement in such environments, characterized by reduced toughness and fracture toughness and accelerated fatigue crack propagation. This poses a significant threat to the safe operation of hydrogen storage and transport equipment. [Methods] The process of high-pressure hydrogen embrittlement is extremely complex, encompassing the physical adsorption of hydrogen on the material surface, chemical adsorption, as well as the dissolution, diffusion, and segregation of hydrogen atoms within the material. Numerous scholars have conducted in-depth studies on hydrogen embrittlement theories, forming various hypotheses, including hydrogen pressure theory, hydrogen-enhanced decohesion, hydrogen-enhanced localized plasticity, adsorption-induced dislocation emission, and hydrogen-enhanced strain-induced vacancy theory. However, these theories typically explain only certain aspects of hydrogen embrittlement and cannot independently account for all phenomena. In general, hydrogen embrittlement results from the combined effect of multiple mechanisms. To ensure safety, standards such as ASME VIII-3, JPEC-TD-0003, and T/CATSI 05003 mandate hydrogen compatibility testing for materials used in high-pressure hydrogen storage vessels. Hydrogen compatibility testing of materials involves directly testing the mechanical properties of materials in a high-pressure hydrogen environment. This includes tests like hydrogen embrittlement sensitivity, slow strain rate tensile, fatigue crack propagation rate, fatigue, and hydrogen-induced cracking stress intensity factor threshold tests. [Results] The hydrogen embrittlement sensitivity test is primarily used for the qualitative evaluation of a material's hydrogen embrittlement performance, while other tests provide basic data for the design of hydrogen storage and transport equipment. This testing must consider the impact of service conditions, environment, and stress on the results. Hydrogen compatibility testing apparatuses have high requirements for functionality and safety, including high-pressure hydrogen environment chambers, loading systems, displacement and gas supply systems, signal acquisition and processing systems, and safety assurance systems. Currently, only a few institutions have developed such testing equipment globally, resulting in scarce data on material hydrogen compatibility testing. In China, Zhejiang University has developed a 140-MPa high-pressure hydrogen environment material performance testing apparatus, meeting the testing requirements of various tests in GB/T 34542.2 and is at the forefront of testing capabilities worldwide. [Conclusions] Using the material 4130X as an example, fatigue crack growth rate tests were conducted in air and 50-MPa hydrogen. The results showed that high-pressure hydrogen significantly accelerated the fatigue crack propagation of 4130X. The acceleration level increased gradually with the extension of the crack and eventually stabilized. The fatigue crack growth rate in 50-MPa hydrogen was approximately 20 times that in air. [ABSTRACT FROM AUTHOR]

In this paper, we investigated the stickiness effect of the Hamilton system of the Hydrogen atom exposed to intense laser field. Even for the one electron system, its Poincare surface of section shows the chaotic and regular parts due to the laser field which can be explained by KAM (Kolmogorov, Arnold, and Moser) theory. The unstable periodic orbit (UPO) in chaotic "sea" was located by variational method and the corresponding stable manifold (SM) and unstable manifold (UM) of the UPO were numerically calculated. It was shown that the dynamics of ionization of the one electron system is governed by the UPO. On one hand, the SM of UPO is well superposed with the recurrence plot, which indicates that the SM overlaps just the stable initial points in phase space. On the other hand, the UM is almost coincide with the densely distributed points on Poincare surface of section. This indicated that the UM is just the ionization channels of the trajectories driven by laser field. Furthermore, the survival probabilities of different regions which gradually cross the UM and SM tangential flow nearby the stable island are studied. They obey an algebraic decaying law. The similar decay trend are also observed on different regions on the UM which possess almost the same decay parameters with that of region nearby the UPO. These observations confirmed that the stability properties of UPO play very important role in the stickiness effect of the phase space nearby the KAM stable islands. [ABSTRACT FROM AUTHOR]

Triacetone triperoxide (TATP) explosive is frequently used by criminals because of its high power and easy preparation. Therefore, the traceability analysis of TATP is of great significance for fighting crime and maintaining public safety. The stable isotope ratio mass spectrometry (IRMS) is a high-precision tool for the measurement of stable isotope ratio, which has been widely used in food science. environmental protection, geology, forensic science, and other fields. A few of studies have been reported to apply IRMS to analyze the isotopic ratio of TATP, verifing the feasibility of using IRMS to distinguish TATP from different sources. However, to realize the precise source tracing of TATP, it is necessary to further study the influence of synthetic raw materials and processes on the stable isotope ratio of TATP. To the end, in this work IRMS was used to explore the characteristics of stable isotope ratio of TATP synthesized by different raw materials and processes. We revealed that the values of carbon isotope (C). hydrogen isotope values (H) and oxygen isotope values (O) of TATP ranged from 31.62% to 27. 50% (SD<0.06%). from 144.09% to -107.85% (SD 2. 78%) and from 30. 61% to 38. 02% (SD <0.5%), respectively. The variation in carbon and hydrogen isotope values mostly determined by the isotopic composition of the precursor acetone, which was the donor of the carbon atoms and the main donor of hydrogen atoms in TATP. The variation in oxygen isotope values mostly depended on the isotopic composition of the precursor hydrogen peroxide, which was the donor of oxygen atoms in TATP. Significantly, the reaction pathway of TATP synthesized from acetone and hydrogen peroxide was postulated based on the results of IRMS. Moreover, a linear relationship was found for the carbon isotope values of the precursor acetone and TATP. This can be used in forensic investigations to link TATP samples to their corresponding acetone precursors. The linear relationship of the hydrogen isotope values of the precursor acetone and TATP was poor because of the possible hydrogen exchange during the synthesis. Benzoic acid serving as a catalyst has no significant impact on the stable isotope ratios of TATP. However the reaction time has a great influence on the isotopic composition of TATP. With the increasing of reaction time, the reaction yields increased and the carbon isotope values of TATP also increased because of the kinetic isotope effect. These finding are of great significance for investigating the source of TATP at the crime scene. [ABSTRACT FROM AUTHOR]

Copyright of Electroplating & Finishing is the property of Electroplating & Finishing Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective Hydrogen diffusion law and performance of Q345R( HIC), SA516 Gr70N+ 316L composite steel plate and 316L in wet H2S environment was studied by hydrogen osmosis technology. Methods The atomic hydrogen concentration, effective diffusion coefficient, strength, toughness and fracture morphology of the materials under different pH conditions were compared by methods of electrochemical hydrogenation technique, tensile test, impact test and fracture analysis. Results The results show that the concentration of atomic hydrogen Co and the effective diffusion coefficient Deff( of hydrogen in Q345R( HIC) increase with the decrease of solution pH value. When pH =3, the Co and Deff in Q345R(HIC) materials can reach 17 moL/m³ and 2. 22X 10-10m2/s. The infiltration of large number of hydrogen atoms make the materials produce dislocation pin effect. Hydrogen hardening occurred, and white spots of hydrogen damage appeared in the material. No hydrogen damage occurred in 316L. Conclusion The 316L composite layer can effectively avoid the damage of the diffusion hydrogen on the substrate SA516 Gr7ON or Q345R. For Q345R ( HIC), with the decrease of solution pH value, the more atomic hydrogen infiltrate into the material, the greater the damage of the material performance is. [ABSTRACT FROM AUTHOR]

Copyright of Journal Of Sichuan University (Natural Sciences Division) / Sichuan Daxue Xuebao-Ziran Kexueban is the property of Editorial Department of Journal of Sichuan University Natural Science Edition and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Multiple chitinases are required for effective hydrolysis of insect epidermal chitin and play an indispensable role in insect molting. As chitin is absent in plants and mammals, these enzymes can be potential targets for the design of green insecticides. In this paper, three dual-target inhibitors against the Asian corn borer (Ostrinia furnacalis)-derived chitinases OfChtI and OfChi-h, anacardic acid, di(2- ethylhexyl) phthalate (DEHP), and shionone, were obtained through high-throughput screening of 1 680 natural products. The respective Ki values for OfChtI are 0.57, 0.53 and 3.95 μmol/L, and are 0.48, 1.42 and 27.33 μmol/L for OfChi-h. The molecular docking results showed that all three inhibitors were bound to the substrate-binding sites of the target enzymes through hydrophobic stacking interaction. In addition, the 1-carboxyl oxygen atom of anacardic acid, as a hydrogen bond acceptor, formed hydrogen bonds with guanidine hydrogen atoms of Arg274 side chain in OfChtI and Arg439 side chain in OfChih, respectively. The carbonyl and etheryl oxygen atoms of DEHP, as hydrogen bond receptors, formed hydrogen bonds with hydrogen atoms of Arg274 guanidine group side chain in OfChtI; the etheryl oxygen atom of DEHP, as a hydrogen bond acceptor, formed hydrogen bond with guanidine hydrogen atom of Arg439 side chain in OfChi-h. The insecticidal activity was determined to be 33.3% for anacardic acid and DEHP at 2 mmol/L, while shionone showed no obvious insecticidal activity. This study may provide a clue for the development of novel green pesticides targeting multiple chitinases simultaneously. [ABSTRACT FROM AUTHOR]

Biodiesel has been one of the most promising types of renewable and clean energy. Replacing fossil fuels with biodiesel can effectively reduce environmental pollution and the consumption of non-renewable energy. It is often produced by a transesterification reaction between methanol and triglyceride under the action of a catalyst. The catalyst is indispensable during reactions. Homogeneous catalyst has been widely used in industrial applications. But the homogeneous catalyst is difficult to separate and easy to saponify with oil. Fortunately, solid catalysts behave the high activity and are easy separation from the solution. In this study, a solid catalyst was fabricated with γ-Al2O3 as a carrier, while Sr and Zn as active atoms. γ-Al2O3 has been widely used as the carrier of active substances, due to the high thermal stability and developed micro pore structure. The strontium doped γ-Al2O3 presented a high catalytic activity for transesterification reaction, due to the high basic strength of Sr atom. Zinc atom was added to form the diatomic catalyst. Zn atom served as the dual properties of acid and base, which adsorbed the acid grease for esterification reaction. Doping both Sr and Zn atoms into γ-Al2O3 can effectively improve the yield of biodiesel. A γ-Al2O3 (110) surface model, strontium doped γ-Al2O3 (110) surface model, and Sr-Zn doped γ-Al2O3 (110) surface model were constructed. The surface doping energy of Sr and Sr-Zn doped catalysts was calculated to obtain the most stable surface. A system evaluation was made to clarify the influence of atomic doping on the stability of the catalysts. After that, the catalyst adsorption model of methanol was established to take the most stable surface as the adsorption carrier. The adsorption energy of methanol on different catalysts was calculated to obtain the best adsorption site of methanol on the catalyst surface. An investigation was made to explore the influence of zinc doping on the catalyst adsorption effect of methanol. Mulliken charge layout was selected to analyze the charge density of each atom in methanol molecule under various adsorption states. The state density and differential charge density of methanol adsorption were also calculated on different catalysts, and the atomic bonding trend, charge transfer amount and charge transfer direction before and after methanol adsorption on the catalyst surface were obtained to explore the mechanism of the catalyst in the transesterification reaction. There was the minimum doping energy on the catalyst surface when the Sr atom was added to the different sites on γ-Al2O3 (110) surface, where the Sr atom was tended to replace Al3c-1 and Al4c-2 coordination aluminum. Zn atom tended to coordinate with Al4C-4 when doping, indicating the minimal doping energy on the catalyst surface. Specifically, the O atom of the methanol molecule gained charge, but the H atom lost charge, where the H atom on the methanol hydroxyl group was bonded with the O atom on the catalyst surface when Sr/γ-Al2O3 and Sr-Zn/γ-Al2O3 (110) surfaces adsorbed methanol. The absolute value of adsorption energy on the surface of the catalyst adsorption methanol increased, when Zn atom doped Sr/γ-Al2O3 (110) surface, indicating the adsorption energy of −305.60 kJ/mol. The number of electrons also increased to gain by oxygen atom on methanol. Hydrogen atoms on the hydroxyl group were bonded better to the surface of the catalyst. Both Sr/γ-Al2O3 and Sr-Zn/γ-Al2O3 can activate methanol effectively, particularly with the stability of Sr/γ-Al2O3 catalyst that is enhanced by Zn atomic doping. The solid catalyst can also greatly contribute to the subsequent biodiesel synthesis. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Test & Measurement Technology is the property of Publishing Center of North University of China and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Copyright of Shipin Kexue/ Food Science is the property of Food Science Editorial Department and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

We compared the sodium-water reaction in vapor sodium phase at 1273 K with that in the sodium/metal multiphase domain by applying the accelerated quantum chemical molecular dynamics method. Considering the gas/liquid mixture condition on the sodium-water interface as well as the solid reaction products such as sodium oxides, the sodium-water reaction itself is regarded as multiphase reaction. In case of the water adsorption over the vapor sodium phase, sodium atoms lost electrons, and desorbed as hydrogen molecule. In case of the sodium vapor over the transition metal titanium surface, a pair of hydrogen atom was produced. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Ecology & Rural Environment is the property of Journal of Ecology & Rural Environment Editorial Office and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Based on B3LYP method of quantum chemistry methods, the optimized structure and frequency of the aromatic acid and single-molecule water system were calculated using the GAUSSIAN09 at B3LYP/6-311 + +G (d, p) level. Quantum chemical simulation was used to study the structure changes, charge distribution, frequency changes and the binding energy. AIM theory was used to study the electron density of the system topology. The results show that all the systems form two hydrogen bonds, the hydrogen 1 (the hydrogen atom in the carboxyl group as a proton donor) is stronger than the hydrogen 2 (the hydrogen atom in water as a proton donor) . The hydrogen 1 plays a leading role of affecting the binding energy. In the system of aromatic acid and single-molecule water, the binding energy is in the range of 38. 0-40. 0 kj/mol which decreases with the increase of aromatic ring. [ABSTRACT FROM AUTHOR]