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Chinese Chemical Letters 2014年第1期25卷 163-165页

作者： yong-hai hui yong-Cheng Chen hai-Wei Gong Zheng-Feng Xie Key Laboratory of Oil & Gas Fine Chemicals Ministry of Education & Xinjiang Uyghur Autonomous RegionCollege of Chemistry and Chemical EngineeringXinjiang University

A new, convenient and excellent yield procedure for the preparation of bis（indolyl）methanes （BIMs） by Friedel-Crafts reaction of indoles with imines in the presence of dithiocarbohydrazone Schiff base/ Zn（CIO4）2.6H2O as a highly stable, effective and readily available catalyst is described. Moderate to good yields （up to 99% yield） were obtained with both substrates for imine derivatives. This procedure is simple, practical and economic.

关键词： Friedel-Crafts reaction Indoles Imines BIMs

Catalytic conjugate addition of indole toα,β-unsaturated ketones by Co(ClO_4)-2·6H_2O/bis-Schiff base complexes

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Chinese Chemical Letters 2012年第5期23卷 525-528页

作者： yong hai hui Chun Mei Chen Zheng Feng Xie Key Laboratory of Oil and Gas Fine Chemicals Ministry of Education and Xinjiang Uyghur Autonomous RegionCollege of Chemistry and Chemical EngineeringXinjiang UniversityUrumqi 830046China

Co（ClO_4））_2·6H_2O/bis-Schiff base complexes promoted the conjugate addition of indole toα,β-unsaturated ketones under mild conditions,giving the corresponding addition products with high *** the complex has bee... 详细信息

关键词： Conjugate addition Indole α β-Unsaturated ketone Schiff base

A catalysis study of mesoporous MCM-41 supported Schiff base and CuSO_4·5H_2O in a highly regioselective synthesis of 4-thiazolidinone derivatives from cyclocondensation of mercaptoacetic acid

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Chinese Chemical Letters 2016年第3期27卷 335-339页

作者： hai-Xia Pang yong-hai hui Kui Fan Xue-Jian Xing Yang Wu Jing-hui Yang Wei Shi Zheng-Feng Xie Key Laboratory of Oil & Gas Fine Chemicals Ministry of Education & Xinjiang Uyghur Autonomous RegionCollege of Chemistry and Chemical EngineeringXinjiang University Oil & Gas Field Applied Chemistry Key Laboratory of Sichuan Province School of Chemistry and Chemical EngineeringSouthwest Petroleum University

Mesoporous MCM-41 supported Schiff base and Cu SO4· 5H2 O shows high catalytic activity in the cyclocondensation of mercaptoacetic acid with imines（or aldehydes and amines） to afford pharmaceutically important thiazolidinone derivatives. The catalytic reactions involving twocomponents or three-components afforded the desired product in high yields（up to 98% and 99%）.Moreover, the catalyst works well with respect to recyclability, giving the product in 85% and 83% yields after recycling six times.

关键词： MCM-41 Schiff base Cyclocondensation Mercaptoacetic acid Catalysis

Aza-Michael addition reactions between nitroolefins and benzotriazole catalyzed by MCM-41 immobilized heteropoly acids in water

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Chinese Chemical Letters 2013年第1期24卷 28-30页

作者： Shao-Lei Xie yong-hai hui Xiang-Ju Long Chang-Chun Wang Zheng-Feng Xie Key Laboratory of Oil & Gas Fine Chemicals Ministry of Education & Xinjiang Uyghur Autonomous RegionCollege of Chemistry and Chemical EngineeringXinjiang University

MCM-41 supported heteropoly acids （HPAs） catalysts were synthesized, characterized and their catalytic activity was evaluated in an aza-Michael addition reaction between nitroolefins and benzotriazole in water at room temperature. 50 wt% PW/MCM-41 showed the highest activity （up to 96% yield）. The catalyst was used in six consecutive experiments without obvious loss of activity, confirming the success of the anchoring process and the catalyst stability.

关键词： Aza-Michael additionMCM-41Heteropoly acidsHeterogenous catalysts

Mn(OAc)_2/Schiff base as a new efficient catalyst system for the Henry reaction of nitroalkanes with aldehydes

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Chinese Chemical Letters 2012年第6期23卷 690-694页

作者： Guang Peng Zhou yong hai hui Ning Ning Wan Qiu Ju Liu Zheng Feng Xie Ji De Wang Key Laboratory of Oil and Gas Fine Chemicals Ministry of Education and Xinjiang Uyghur Autonomous RegionCollege of Chemistry and Chemical Engineering Xinfiang University Urumqi 830046 China

A series of novel Schiff bases bearing triazole structure were synthesized and characterized by LR and NMR. Mn（OAc）2/Schiff base efficiently catalyzed Henry reaction of nitroalkanes with aldehydes to produce the corresponding products of ^-nitroalcohols, under mild conditions with high yields （up to 99%）. A reaction mechanism is proposed based on the experimental results.

关键词： Schiff base Henry reaction Aldehydes Nitroalkanes

A Study on the Impact of Chemical Structure on the Evolution of Aggregate Structure in Fiber-shaped High Density Polyethylene Vitrimer

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Chinese Journal of Polymer Science 2024年第10期42卷 1557-1565,I0013页

作者： Bing Wang Yuan-Chu Gao hai Wang hui Niu State Key Laboratory of Fine Chemicals School of Chemical EngineeringDalian University of TechnologyDalian116024China

Vitrimers have emerged as a prominent research area in the field of polymer *** of the studies have focused on synthesizing polymers with versatile dynamic crosslinking structures,while the impact of chemical structure on aggregate structure of vitrimers,particularly during polymer processing,remains insufficiently *** present study employed commercial maleic anhydride-grafted-high density polyethylene(M-g-HDPE)as the matrix and hexanediol as the crosslinker to facilely obtain fiber-shaped HDPE vitrimers through a reaction extrusion and post-drawing *** chemical structure characterization,morphology observation,thermal and mechanical properties investigation,as well as aggregate structure analysis,this work revealed the influence of dynamic bonds on the formation of aggregate structures during fiber-shaped vitrimers processing.A small amount of dynamic bonds in HDPE restricts the motion of PE chain during melt-extruding and post-drawing,resulting in a lower orientation of the PE ***,lamellar growth and fibril formation during post-drawing at high temperature are enhanced to some extent due to the competition between dynamic bond and chain *** uneven morphology of fibershaped HDPE vitrimers can be attributed to the stronger elastic effect brought by dynamic bonding,which plays a more dominant role in determining the mechanical properties of fiber-shaped vitrimers compared to aggregate *** Vitrimers have emerged as a prominent research area in the field of polymer *** of the studies have focused on synthesizing polymers with versatile dynamic crosslinking structures,while the impact of chemical structure on aggregate structure of vitrimers,particularly during polymer processing,remains insufficiently *** present study employed commercial maleic anhydride-grafted-high density polyethylene(M-g-HDPE)as the matrix and hexanediol as the crosslinker to facilely obtain fiber-shap

关键词： High density polyethylene vitrimer Fiber-shaped Aggregate structures Transesterification reaction

Prefrontocortical Astrocytes Regulate Dominance Hierarchy in Male Mice

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Neuroscience Bulletin 2024年第3期40卷 415-417页

作者： yong Tang hai-Yan Yin Peter Illes School of Acupuncture and Tuina Chengdu University of Traditional Chinese MedicineChengdu 610075China International Joint Research Center on Purinergic Signaling Chengdu University of Traditional Chinese MedicineChengdu 610075China Rudolf Boehm Institute for Pharmacology and Toxicology University of Leipzig04107 LeipzigGermany

Social hierarchy is a general self-organizational scheme in animal societies in which each member achieves a certain status of domination or subordination when getting access to resources,with profound consequences for survival,health,reproductive success,and multiple behaviors[1,2].The prefrontal cortex(PFC)was recognized as a central regulator of neuronal circuits determining the formation of social hierarchy;brain areas upstream of the PFC convey information about social status,and downstream brain regions execute dominance behavior[3].Social deficits have been suggested to be due to an elevation of excitatory/inhibitory(E/l)balance within the mouse dorsomedial(dm)PFC[4].A compensatory increase of inhibitory cell excitability partially rescued social deficits caused by such a disturbance of E/l balance.

关键词： consequences hierarchy determining

Dynamics of a Reaction-diffusion-ODE System in a Heterogeneous Media

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Acta Mathematicae Applicatae Sinica 2024年第2期40卷 275-301页

作者： Cong-hui ZHANG hai-feng ZHANG Mei-rong ZHANG School of Science Beijing University of Civil Engineering and ArchitectureBeijing 102616China Institute of Applied System Analysis Jiangsu UniversityZhenjiang 212013China Department of Mathematical Sciences Tsinghua UniversityBeijing 100084China

The existence and stability of stationary solutions for a reaction-diffusion-ODE system are investigated in this *** first show that there exist both continuous and discontinuous stationary *** a good understanding of the stability of discontinuous stationary solutions is gained under an appropriate *** addition,we demonstrate the influences of the diffusion coefficient on stationary *** results we obtained are based on the super-/sub-solution method and the generalized mountain pass ***,some numerical simulations are given to illustrate the theoretical results.

关键词： reaction-diffusion-ODE system discontinuous stationary solutions stability asymptotic behavior monotone solutions

Strength and ductility optimization of HPDC AlSi8MgCuZn2 alloys by modifying pre-aging treatment

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China Foundry 2024年第4期21卷 343-351页

作者： Yuan-hang Jiang hui-ting Zheng Fei Liu hai-dong Zhao National Engineering Research Center of Near-net Shape Forming for Metallic Materials South China University of TechnologyGuangzhou 510641China

Considering the components produced by high pressure die casting(HPDC)process usually with ultra-large sizes and complex morphologies,high temperature solid solution treatment is not a suitable method to further improve their mechanical *** this study,two-stage aging treatment with different pre-aging times was designed and employed to further improve the mechanical properties of HPDC Al8SiMgCuZn *** characteristics of precipitates were evaluated by a transmission electron microscope(TEM),and the precipitation strengthening mechanism was *** results reveal that the strengthening is mainly contributed by the precipitation ofβ″phase after two-stage aging,and the number density and size of the precipitates are significantly depended on the pre-aging *** number density of precipitates is increased with the pre-aging time prolonged from 0 h to 4 h,and then decreases with the further increase of pre-aging time from 4 h to 6 *** precipitates with the highest density and smallest size are observed after pre-aging for 4 *** pre-aged at 100℃for 4 h and then artificial aged at 200℃for 30 min,the yield strength of 207 MPa,ultimate tensile strength of 325 MPa and elongation of 7.6%are achieved.

关键词： high pressure die cast aluminum alloy microstructural heterogeneity mechanical properties precipitation strengthening two-stage aging

Effect of low-speed waterjet pressure on the rock-breaking performance of unsubmerged cavitating abrasive waterjet

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Petroleum Science 2024年第4期21卷 2638-2649页

作者： Chen-Xing Fan Deng Li yong Kang hai-Tao Zhang Hubei Key Laboratory of Waterjet Theory and New Technology Wuhan University School of Power and Mechanical Engineering Wuhan University

Unsubmerged cavitating abrasive waterjet(UCAWJ) has been shown to artificially create a submerged environment that produces shear cavitation, which effectively enhances rock-breaking performance. The shear cavitation generation and collapse intensity depend on the pressure difference between the intermediate high-speed abrasive waterjet and the coaxial low-speed waterjet. However, the effect of the pressure of the coaxial low-speed waterjet is pending. For this purpose, the effect of low-speed waterjet pressure on rock-breaking performance at different standoff distances was experimentally investigated,and the effects of erosion time and ruby nozzle diameter on erosion performance were discussed. Finally,the micromorphology of the sandstone was observed at different locations. The results show that increased erosion time and ruby nozzle diameter can significantly improve the rock-breaking performance. At different standoff distances, the mass loss increases first and then decreases with the increase of low-speed waterjet pressure, the maximum mass loss is 10.4 g at a low-speed waterjet pressure of0.09 MPa. The surface morphology of cavitation erosion was measured using a 3D profiler, the increase in both erosion depth and surface roughness indicated a significant increase in the intensity of the shear cavitation collapse. At a low-speed waterjet pressure of 0.18 MPa, the cavitation erosion surface depth can reach 600 μm with a roughness of 127 μm.

关键词： Rock-breaking Coaxial low-speed waterjet pressure Abrasive waterjet Cavitation Unsubmerged environment