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Transactions of Nonferrous Metals Society of China 2022年第1期32卷 104-121页

作者： Zhi-ping GUAN Ming-yu LI kai-xin xia Zhi-gang LI Dan GAO Po ZHAO Pin-kui MA Jia-wang SONG State Key Laboratory of Automotive Simulation and Control Jilin UniversityChangchun 130022China School of Materials Science and Engineering Jilin UniversityChangchun 130022China

SiC_(p)/AZ91 composites were prepared by vacuum pressure *** microstructure,mechanical properties and wear resistance of composite were *** indicated that SiC particles were uniformly distributed in the metal matrix and had a good interface bonding with the metal ***_(17)Al_(12) preferably precipitated near the SiC particles,and high-density dislocations were induced by the mismatch of the coefficient of thermal expansion(CTE)between the SiC particle and the AZ91 matrix,thereby accelerating the aging precipitation of the *** with AZ91 alloy,the addition of SiC particles improves the hardness and compressive strength of the composite,which is mainly due to the load transfer strengthening and grain refinement strengthening ***,a stable support surface-protecting matrix formed during the wear process because of the excellent wear resistance of SiC.

关键词： magnesium matrix composites SiC particle vacuum pressure infiltration aging behavior wear

Palladium installed copper-organic framework for C–C coupling reactions

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Science China Chemistry 2025年

作者： Yu-Mei Wang Mei-xia Tao kai-Ming Mo Xu Chen Shu-Hua Zhong Elena S Shubina Guo-Hong Ning Dan Li College of Chemistry and Materials Science Guangdong Provincial Key Laboratory of Supramolecular Coordination ChemistryJinan University A.N.Nesmeyanov Institute of Organoelement Compounds Russian Academy of Sciences

The formation of C–C bonds is a crucial aspect of organic synthesis. Synthesists' long-term objective is to identify novel catalysts to optimize reaction systems based on traditional transition metal catalysis. This study explores the synthesis and catalytic potential of palladium-installed covalent metal-organic frameworks(CMOFs) based on copper cyclic trinuclear units(Cu-CTUs). By incorporating palladium ions into the imine-based framework JNM-7 through a straightforward immersion method, we achieved a notable enhancement in catalytic activity for critical C–C coupling reactions, including C–H arylation and Sonogashira cross-coupling. The resulting JNM-7-Pd demonstrated remarkable stability and recyclability, maintaining its efficiency over at least three cycles without any decline in efficiency.

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A tip clearance prediction model for multistage rotors and stators in aero-engines

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Chinese Journal of Aeronautics 2021年第2期34卷 343-357页

作者： Huibin SUN Jing WANG kai CHEN Huateng xia xin FENG Zhiyong CHANG Key Laboratory of High Performance Manufacturing for Aero Engine Ministry of Industry and Information TechnologyNorthwestern Poly technical UniversityXi'an 710072China AECC South Industry Company Limited Zhuzhou 412002China

Tip clearances of multistage rotors and stators greatly affect aero-engines’ aerodynamic efficiency, stability and safety. The inevitable machining and assembly errors, as well as the complicated error propagation mechanism, cause overproof or non-uniform tip clearances. However, it is generally accepted that tip clearances are difficult to predict, even under assembly state. In this paper, a tip clearance prediction model is proposed based on measured error data. Some 3 D error propagation sub-models, regarding rotors, supports and casings, are built and combined. The complex error coupling relationship is uncovered using mathematical methods. Rotor and stator tip clearances are predicted and analyzed in different phase angles. The maximum, minimum and average tip clearances can be calculated. The proposed model is implemented by a computer program,and a case study illustrates its performance and verifies its feasibility. The results can be referred by engineers in assembly quality judgement and decision-making.

关键词： Tip clearance Prediction Error propagation model Rotor and stator Aero-engine Assembly

Simultaneously Improving the Tensile and Impact Properties of Isotactic Polypropylene with the Cooperation of co-PP and β-nucleating Agent through Pressure Vibration Injection Molding

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Chinese Journal of Polymer Science 2016年第8期34卷 1001-1013页

作者： Man Zhou xin-peng Li Ming Jin Chao xia kai-zhi Shen 张杰 College of Polymer Science and Engineering State Key Laboratory of Polymer Materials Engineering Sichuan University Chengdu 610065 China

In this article, crystalline morphology and molecular orientation of isotactic polypropylene （iPP）, random copolymerized polypropylene （co-PP） and ,β-nucleating agent （β-NA） composites prepared by pressure vibration injection molding （PVIM） have been investigated via polarized light microscopy, scanning electron microscopy, wide-angle X-ray diffraction and differential scanning calorimetry. Results demonstrated that the interaction between co-PP and iPP molecular chains was beneficial for the mechanical improvement and the introduction of β-NA further improved the toughness of iPP. In addition, after applying the pressure vibration injection molding （PVIM） technology, the shear layer thickness increased remarkably and the tensile strength improved consequently. Thus, the strength and toughness of iPP/co-PP/β-NA composites prepared by PVIM were simultaneously improved compared to those of the pure iPP prepared by conventional injection molding （CIM）： the impact toughness was increased by five times and tensile strength was increased by 9 MPa. This work provided a new method to further enhance the properties of iPP/co-PP composites through dynamic processing strategy.

关键词： Mechanical properties Orientation structures Periodical shear field Morphology.

Coordinated organogel templated fabrication of silver/polypyrrole composite nanowires

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Chinese Chemical Letters 2011年第1期22卷 123-126页

作者： Bo Tian Li Li Ming Tang kai Chen Yu xia xin Jin Laboratory of Advanced Materials Department of Chemical Engineering Tsinghua University Beijing 100084 China

A new method to fabricate metal/conducting polymer composite nanowires is presented by taking silver/polypyrrole composite nanowires as an example. A silver （D-coordinated organogel as template was prepared firstly, and redox-polymerization of pyrrole took place on the gel fiber, giving product of silver/polypyrrole nanowires. The silver/polypyrrole nanowires were characterized by multiple techniques. This strategy could be carried out in one-step procedure at room temperature, and it proves the utility of coordinated organogels in template synthesis of polymer nanostructures.

关键词： Coordinated organogel Template polymerization Polypyrrole Composite nanowires

Breaking the linear correlations for enhanced electrochemical nitrogen reduction by carbon-encapsulated mixed-valence Fe_(7)(PO_(4))_(6)

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Journal of Energy Chemistry 2022年第8期31卷 182-187,I0006页

作者： Lehui Ma Fanfan Xu Linlin Zhang Zhongfen Nie kai xia Mingxia Guo Mingzhu Li xin Ding College of Chemistry and Chemical Engineering Qingdao UniversityQingdao 266071ShandongChina

Electrochemical nitrogen reduction(NRR)is deemed as a consummate answer for the traditional Haber–Bosch *** the linear correlations between adsorption and transition-state energies of intermediates is vital to improve the kinetics of ammonia synthesis and obtain a less energy-intensive ***,carbon-encapsulated mixed-valence Fe_(7)(PO_(4))_(6) was prepared and applied as an electrocatalyst for high-efficiency NRR.A dramatic faradaic efficiency(FE)of 36.93%and an NH_(3) production rate of 13.1μg h^(-1) mg_(cat)^(-1) were obtained at-0.3 V versus RHE,superior to nearly all Fe-based *** and DFT calculations revealed that the superior performance was ascribed to the synergistic effect of mixed-valence iron pair,which braked the linear correlations to improve the kinetics of ammonia from collaborative hydrogenation and*NH_(3) *** work proves the feasibility of mixedvalence catalysts for nitrogen reduction and thus opening a new avenue towards artificial nitrogenfixation catalysts.

关键词： N2 reduction reaction(NRR) Mixed-valence Linear correlations Nitrogen fixation N_(2)activation

Effects of stocking density on growth performance, blood parameters and immunity of growing pigs

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Animal Nutrition 2020年第4期6卷 529-534页

作者： Xue Li xia Xiong xin Wu Gang Liu kai Zhou Yulong Yin Scientific Observing and Experimental Station of Animal Nutrition and Feed Science in South-Central Ministry of AgricultureHunan Provincial Engineering Research Center of Healthy LivestockKey Laboratory of Agro-ecological Processes in Subtropical RegionInstitute of Subtropical AgricultureChinese Academy of SciencesChangshaHunan410125China University of Chinese Academy of Science Beijing100049China Key Laboratory of Adaptation and Evolution of Plateau Biota Qinghai Key Laboratory of Animal Ecological GenomicsLaboratory of Plateau Fish Evolutionary and Functional GenomicsNorthwest Institute of Plateau BiologyChinese Academy of SciencesXining810001China

This study was conducted to evaluate the effects of different stocking densities on growth performance,blood parameters,intestinal morphology and intestinal immunity of growing pigs.A total of288 male pigs(44.35±0.50 kg)were randomly assigned to groups with stocking densities of 2.46,1.23 and 0.82 m2/pig for a *** results showed that there was no significant difference on growth performance among *** in the stocking density of 0.82 m2/pig had the lowest backfat thickness and spleen weight index among groups(P<0.05).With increasing stocking density,the serum concentrations of blood urea nitrogen(BUN),transglutaminase(TGG),alkaline phosphatase(AKP)and immunoglobulin A(Ig A)were increased,and albumin(ALB),albumin-to-globulin ratio(ALB:GLO),insulin-like growth factor-1(IGF-1)and immunoglobulin(Ig M)were decreased(P<0.05),and cortisol tended to increase and glucose tended to decrease(0.05

关键词： Stocking density Growth performance Blood parameter Intestinal morphology Growing pig

Heteroatom tuning in agarose derived carbon aerogel for enhanced potassium ion multiple energy storage

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Carbon Energy 2024年第3期6卷 239-254页

作者： kaijun Xie xin Liu Haolin Li Long Fang kai xia Dongjiang Yang Yihui Zou xiaodong Zhang State Key Laboratory of Bio-fibers and Eco-textiles Shandong Collaborative Innovation Center of Marine Biobased Fibers and Ecological TextilesInstitute of Marine Biobased MaterialsCollege of Chemistry and Chemical EngineeringCollege of Environmental Science and EngineeringQingdao UniversityQingdaoChina

The incorporation of heteroatoms into carbon aerogels(CAs)can lead to structural distortions and changes in active sites due to their smaller size and electronegativity compared to pure ***,the evolution of the electronic structure from single-atom doping to heteroatom codoping in CAs has not yet been thoroughly investigated,and the impact of codoping on potassium ion(K+)storage and diffusion pathways as electrode material remains *** this study,experimental and theoretical simulations were conducted to demonstrate that heteroatom codoping,composed of multiple heteroatoms(O/N/B)with different properties,has the potential to improve the electrical properties and stability of CAs compared to single-atom *** states near the Fermi level have revealed that doping with O/N/B generates a greater number of active centers on adjacent carbon atoms than doping with O and O/N *** a result of synergy with enhanced wetting ability(contact angle of 9.26°)derived from amino groups and hierarchical porous structure,ON-CA has the most optimized adsorption capacity(−1.62 eV)and diffusion barrier(0.12 eV)of K^(+).The optimal pathway of K^(+)in ON-CA is along the carbon ring with N or O *** K^(+)storage material for supercapacitors and ion batteries,it shows an outstanding specific capacity and capacitance,electrochemical stability,and rate ***,the assembled symmetrical K^(+)supercapacitor demonstrates an energy density of 51.8 Wh kg^(−1),an ultrahigh power density of 443Wkg^(−1),and outstanding cycling stability(maintaining 83.3%after 10,000 cycles in 1M KPF6 organic electrolyte).This research provides valuable insights into the design of highperformance potassium ion storage materials.

关键词： agarose carbon aerogels O/N/B codoping potassium-ion battery potassium-ion supercapacitor

Regulation of Circadian Genes by the MAPK Pathway:Implications for Rapid Antidepressant Action

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Neuroscience Bulletin 2020年第1期36卷 66-76页

作者： xin-Ling Wang kai Yuan Wen Zhang Su-xia Li George Fu Gao Lin Lu Savaid Medical School University of the Chinese Academy of SciencesBeijing 101408China Peking-Tsinghua Center for Life Sciences and PKU-IDG/McGovern Institute for Brain Research Peking UniversityBeijing 100191China National Institute on Drug Dependence and Beijing Key Laboratory on Drug Dependence Research Peking UniversityBeijing 100191China Key Laboratory of Pathogenic Microbiology and Immunology Institute of MicrobiologyChinese Academy of SciencesBeijing 100101China Chinese Center for Disease Control and Prevention Beijing 102206China Institute of Mental Health National Clinical Research Center for Mental DisordersKey Laboratory of Mental Health and Peking University Sixth HospitalPeking UniversityBeijing 100191China

Accumulating evidence suggests that the circadian rhythm plays a critical role in mood regulation,and circadian disturbances are often found in patients with major depressive disorder(MDD).The mitogen-activated protein kinase(MAPK)/extracellular signal-regulated kinase(ERK)pathway is involved in mediating entrainment of the circadian ***,the MAPK/ERK signaling pathway has been shown to be involved in the pathogenesis of MDD and the rapid onset of action of antidepressant therapies,both pharmaceutical and *** review provides an overview of the involvement of the MAPK/ERK pathway in modulating the circadian system in the rapid action of antidepressant *** pathway holds much promise for the development of novel,rapid-onset-of-action therapeutics for MDD.

关键词： Major depressive disorder-MAPK pathway Circadian system Rapid antidepressant therapy