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Palladium-catalyzed 3,4-hydroaminocarbonylation of conjugated dienes for formation ofβ,γ-unsaturated amides

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Science China Chemistry 2023年第5期66卷 1474-1481页

作者： hui-yi yang Liang-Quan Lin Na-Qi Li Zhi-hui Ren Zheng-hui Guan Key Laboratory of Synthetic and Nature Molecule of Ministry of Education Department of Chemistry&Materials ScienceNorthwest UniversityXi’an 710127China

Hydrocarbonylation of conjugated dienes is one of the most promising yet challenging methods for the synthesis of carbonyl ***,we reported the development of an unprecedented palladium-catalyzed branched selective 3,4-hydroaminocarbonylation of 1,3-dienes with CO and amines hydrochloride to affordβ,γ-unsaturated *** reaction employs readily available starting materials(including anilines,amines,amino acids,peptides,aryl-1,3-dienes,alyl-1,3-dienes)and tolerates a wide range of functional groups,thus providing a facile and effective approach to access a diverse array ofα-substitutedβ,γ-unsaturated *** investigations suggested that the hydropalladation of dienes is irreversible,and the insertion of CO into the allyl-Pd species is probably the rate-limiting step.

关键词： palladium-catalyzed carbonylation reaction regioselectivity conjugated diene amides synthesis

A simple route for preparation of TRIP-assisted Si-Mn steel with excellent performance using direct strip casting

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International Journal of Minerals,Metallurgy and Materials 2024年第10期31卷 2173-2181页

作者： hui Xu Lejun Zhou Wanlin Wang yang yi School of Metallurgy and Environment Central South UniversityChangsha 410083China National Center for International Research of Clean Metallurgy Central South UniversityChangsha 410083China

The complex producing procedures and high energy-consuming limit the large-scale production and application of advanced high-strength steels(AHSSs).In this study,the direct strip casting(DSC)technology with unique sub-rapid solidification characteristics and cost advantages was applied to the production of low-alloy Si-Mn steel with the help of quenching&partitioning(Q&P)concept to address these *** this method with the conventional compact strip production(CSP)process,the initial microstructure formed under different solidification conditions and the influence of heat treatment processes on the final mechanical properties were *** results show that the initial structure of the DSC sample is a dual-phase structure composed of fine lath martensite and bainite,while the initial structure of the CSP sample consists of pearlite and *** volume fraction and carbon content of retained austenite(RA)in DSC samples are usually higher than those in CSP samples after the same Q&P *** samples typically demonstrate better comprehensive mechanical properties than the CSP *** DSC sample partitioned at 300℃ for 300 s(DSC-Pt300)achieves the best comprehensive mechanical properties,with yield strength(YS)of 1282 MPa,ultimate tensile strength(UTS)of 1501 MPa,total elongation(TE)of 21.5%,and product of strength and elongation(PSE)as high as 32.3 GPa·%.These results indicate that the excellent mechanical properties in low-alloy Si-Mn steel can be obtained through a simple process(DSC-Q&P),which also demonstrates the superiority of DSC technology in manufacturing AHSSs.

关键词： direct strip casting sub-rapid solidification quenching and partitioning TRIP-assisted AHSSs microstructure

Cross-species transmission and host range genes in poxviruses

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Virologica Sinica 2024年第2期39卷 177-193页

作者： Chen-hui yang A-Ling Song Ye Qiu Xing-yi Ge College of Biology Hunan Provincial Key Laboratory of Medical VirologyHunan UniversityChangsha410012China

The persistent epidemic of human mpox, caused by mpox virus (MPXV), raises concerns about the future spread ofMPXV and other poxviruses. MPXV is a typical zoonotic virus which can infect human and cause smallpox-likesymptoms. MPXV belongs to the Poxviridae family, which has a relatively broad host range from arthropods tovertebrates. Cross-species transmission of poxviruses among different hosts has been frequently reported andresulted in numerous epidemics. Poxviruses have a complex linear double-strand DNA genome that encodeshundreds of proteins. Genes related to the host range of poxvirus are called host range genes (HRGs). This reviewbriefly introduces the taxonomy, phylogeny and hosts of poxviruses, and then comprehensively summarizes thecurrent knowledge about the cross-species transmission of poxviruses. In particular, the HRGs of poxvirus aredescribed and their impacts on viral host range are discussed in depth. We hope that this review will provide acomprehensive perspective about the current progress of researches on cross-species transmission and HRGvariation of poxviruses, serving as a valuable reference for academic studies and disease control in the future.

关键词： Poxvirus Host range gene(HRG) Host spectrum Cross-species transmission

Vibration attenuation performance of wind turbine tower using a prestressed tuned mass damper under seismic excitation

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Earthquake Engineering and Engineering Vibration 2024年第2期23卷 511-524页

作者： Lei Zhenbo Liu Gang Wang hui hui yi School of Civil Engineering Chongqing UniversityChongqing 400045China Key Laboratory of New Technology for Construction of Cities in Mountain Area Chongqing UniversityMinistry of EducationChongqing 400045China

With the rapid development of large megawatt wind turbines,the operation environment of wind turbine towers(WTTs)has become increasingly *** particular,seismic excitation can create a resonance response and cause excessive vibration of the *** investigate the vibration attenuation performance of the WTT under seismic excitations,a novel passive vibration control device,called a prestressed tuned mass damper(PS-TMD),is presented in this ***,a mathematical model is established based on structural dynamics under seismic ***,the mathematical analytical expression of the dynamic coefficient is deduced,and the parameter design method is obtained by system tuning ***,based on a theoretical analysis and parameter design,the numerical results showed that the PS-TMD was able to effectively mitigate the resonance under the harmonic basal ***,the time-history analysis method is used to verify the effectiveness of the traditional pendulum tuned mass damper(PTMD)and the novel PS-TMD device,and the results indicate that the vibration attenuation performance of the PS-TMD is better than the *** addition,the PS-TMD avoids the nonlinear effect due to the large oscillation angle,and has the potential to dissipate hysteretic energy under seismic excitation.

关键词： wind turbine tower prestressed tuned mass damper vibration control seismic excitation numerical simulation

Effect of solute Ce,Mn,and Si on mechanical properties of silicon steel:insights from DFT calculations

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Journal of Iron and Steel Research International 2024年第3期31卷 700-709页

作者： Xiang-jun Liu Ji-chun yang hui-ping Ren Xiao-bin Jia Ming-yi Zhang Chang-qiao yang School of Materials and Metallurgy Inner Mongolia University of Science and TechnologyBaotou 014010Inner MongoliaChina Key Laboratory of Integrated Exploitation of Bayan Obo Multi-Metal Resource Inner Mongolia University of Science and TechnologyBaotou 014010Inner MongoliaChina Inner Mongolia North Heavy Industries Group Co. Ltd.Baotou 014010Inner MongoliaChina Inner Mongolia Metal Material Research Institute Baotou 014010Inner MongoliaChina

The influence of solute Ce,Mn,and Si on the mechanical properties of silicon steel was investigated by first-principles ***,Mn,and Si can all be solubilized in Fe *** significantly reduces the incompressibility and rigidity of the system but also significantly improves the toughness and *** effect of Mn on mechanical properties of the system is not *** has a significant effect on the improvement in incompressibility and rigidity but a limited effect on the improvement in toughness and *** metallic bond strength of Fe-Ce,Fe-Mn,and Fe-Si doped systems is weaker than that of the pure Fe system,which can be used to explain the reduction in the incompressibility and rigidity of these doped *** relatively high electron cloud density in the doped system may be responsible for the increase in toughness.

关键词： Silicon steel Rare earth First-principles calculation Elastic modulus Electronic structure

Photocatalytic in situ H_(2)O_(2) production and activation for enhanced ciprofloxacin degradation over CeO_(2)-Co_(3)O_(4)/g-C_(3)N_(4):key role of CeO_(2)

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Rare Metals 2024年第6期43卷 2695-2707页

作者： Hong-Jie Zhu yi-Kai yang Ming-hui Li Lu-Ning Zou Hai-Tao Zhao Shandong Provincial Key Laboratory of Chemical Energy Storage and Novel Cell Technology School of Chemistry and Chemical Engin College of Ecology and Environment Anhui Normal UniversityWuhu241002China Liaocheng yiLu Advanced Materials Co. LtdLiaocheng 252000China

The abused ciprofloxacin antibiotics have caused significant environmental *** oxidative degradation of ciprofloxacin exhibits promising efficacy,it often entails excessive energy ***,it is necessary to explore an effective and ecologically sustainable degradation ***,we demonstrated that g-C_(3)N_(4) decorated with the coordinated CeO_(2)and Co_(3)O_(4)(CeO_(2)-Co_(3)O_(4)/CN)exhibited effective ciprofloxacin photodegradation via in situ H_(2)O_(2) production and activation *** indicate that the introduced CeO_(2) enhances the transference of photogenerated electrons to O_(2) by adjusting the oxygen vacancy of photocatalyst,thereby increasing the generation of superoxide radicals,which in turn generate H_(2)O_(2),resulting in a 22.4-fold increase in H_(2)O_(2) generation over g-C_(3)N_(4).Moreover,the in situ H_(2)O_(2)generation facilitated by CeO_(2) is confirmed to be essential for ciprofloxacin degradation via CeO_(2)-Co_(3)O_(4)/CN,as it provides enough oxidant for Co_(3)O_(4) to activate into hydroxyl radicals for the pollutants ***,CeO_(2)-Co_(3)O_(4)/CN achieves a ciprofloxacin degradation ratio of 97.7%within 80 *** study introduces a novel approach that combines H_(2)O_(2) generation and activation,offering an innovative perspective for achieving clean and efficient purification of antibiotic-contaminated water.

关键词： CeO_(2) In situ H_(2)O_(2)generation Ciprofloxacin degradation Photocatalyst

Cooperative composites anchored with single atom Pb and carbon confined PbO nanoparticles for superior lead-carbon batteries

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Journal of Energy Chemistry 2024年第10期97卷 486-497页

作者： Puqiang He yi yang hui Huang Jing Huang Hongbiao Wang Yapeng He Zhongcheng Guo Faculty of Metallurgical and Energy Engineering Kunming University of Science and Technology Metallurgical Electrode Material Engineering Technology Research Center of Yunnan Province Kunming Hendera Technology Co.LTD.

The mitigation of sulphation and parasitic hydrogen evolution is considered as prominent research emphasis for the development of lead-carbon batteries（LCBs） in large-scale energy storage ***,cooperative Pb-C composites consisting of single atom Pb and carbon-encapsulated PbO nanoparticles were prepared by freeze-drying technique and pyrolytic reduction to address above *** innovative use of Pb2+to cross-link sodium alginate enabled a uniform distribution of Pb in the composites,generating Pb-C-PbO three-phase *** analysis and theoretical calculations revealed the synergistic interactions between single-atom Pb and PbO nanoparticles in suppressing parasitic hydrogen evolution and promoting the adsorption of Pb *** presence of monatomic Pb and PbO enhanced the affinity of the composites for the negative active materials and facilitated the transformation of the active materials from bulk into spherical shapes to enhance the specific surface area,thereby counteracting *** the coordinated integration of various functionalities offered by Pb@C-x,the cycle life of the battery at HRPSoC reaches 7025 cycles,which is two times for LCB with pure carbon ***,the discharge capacity increased from 3.52 to 3.79 *** study provides substantial insights into the construction of Pb-C composites for LCBs to inhibit negative sulphation and hydrogen evolution.

关键词： Hydrogen evolution Lead carbon composites Lead-carbon battery Negative sulphation Single-atom

Cutting performance of saw blades with microtextured rougher and finisher sawteeth

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Advances in Manufacturing 2024年第2期12卷 317-334页

作者： yang Lu Jian-Xin Deng Zhi-hui Zhang Jia-Xing Wu Ran Wang yi-Chen Bao Key Laboratory of High Efficiency and Clean Mechanical Manufacture of MOE School of Mechanical EngineeringShandong UniversityJinan250061People’s Republic of China

The problems of severe sawtooth wear,harsh sawing noise,and low surface quality during the processing of circular saw blades need to be *** improve the cutting performance of TiC-based cermet saw blades,microtextures parallel to the cutting edge were fabricated on rough and fine sawteeth by laser *** cutting tests were performed on a sawing platform under lubricated *** of the sawing arc length and working sawtooth cutting force variations were developed for sawing steel pipes,and the accuracy of the sawing force model was verified *** results indicate that the variations in the sawing force are proportional to the sawing arc *** circular saw blades with microtextures that did not penetrate the sawtooth rake face exhibited the lowest cutting force,sawing noise,and highest machined surface ***,the worn-out distance of the rougher and finisher sawteeth was reduced by approximately 7.4%and 44.1%,respectively,compared with conventional circular saw *** main failure modes of sawteeth were tip wear,rake face adhesion,and oxidative *** addition,the mechanism by which the textures improve the cutting and wear properties of TiC-based circular saw blades was *** study provided a significant concept for enhancing the cutting performance of circular saw blades and improving the machined surface quality.

关键词： Circular saw blades Micro textures Cutting performance Wear performance

Inhibiting shuttle effect of lithium polysulfides by double metal selenides for high-performance lithium-sulfur batteries

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Rare Metals 2024年第6期43卷 2546-2559页

作者： Lei Li Xue-Jing yang yi-yang Li Bo Jin hui Liu Meng-yang Cui Dong-Bo Guan Xing-You Lang Qing Jiang Key Laboratory of Automobile Materials Ministry of Educationand College of Materials Science and EngineeringJilin UniversityChangchun 130022China

Lithium-sulfur batteries(LSBs)have attracted the attention of more and more researchers due to the advantages of high energy density,environmental friendliness,and low production ***,the low electronic conductivity of active material and shuttling effect of lithium polysulfides(LiPSs)limit the commercial development of *** solve these problems,we design a core-shell composite with nitrogen-doped carbon(NC)and two types of selenides(FeSe_(2)-NC@ZnSe-NC).The FeSe_(2)-NC@ZnSe-NC has a strong adsorption capacity,and can effectively adsorb *** the same time,it also effectively alleviates the shuttling effect of LiPSs,and improves the utilization of the active substance during the charge/discharge reaction *** mechanism involved in FeSe_(2)-NC@ZnSe-NC is demonstrated by both experiments and density-functional theory(DFT)*** electrochemical test results indicate that LSB with S/FeSe_(2)-NC@ZnSe-NC delivers an initial discharge capacity of 1260 mAh·g^(-1)at *** after 500 cycles at 1C,the capacity decay rate per cycle is 0.031%,and the capacity retention rate is 85%.The FeSe_(2)-NC@ZnSe-NC core-shell structure verifies a rational strategy to construct an electrode material for high-performance LSBs.

关键词： Lithium-sulfur batteries Shuttling effect Metal selenide Nitrogen-doped carbon Lithium polysulfides