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Combination of a reaction cell and an ultra-high vacuum system for the in situ preparation and characterization of a model catalyst
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作者 Yi-Jing Zang Shu-Cheng Shi +5 位作者 Yong Han Hui Zhang Wei-Jia Wang Peng Liu Mao Ye Zhi Liu 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第5期13-21,共9页
An in-depth understanding of the structure-activity relationship between the surface structure,chemical composition,adsorption and desorption of molecules,and their reaction activity and selectivity is necessary for t... An in-depth understanding of the structure-activity relationship between the surface structure,chemical composition,adsorption and desorption of molecules,and their reaction activity and selectivity is necessary for the rational design of high-performance catalysts.Herein,we present a method for studying catalytic mechanisms using a combination of in situ reaction cells and surface science techniques.The proposed system consists of four parts:preparation chamber,temperatureprogrammed desorption(TPD)chamber,quick load-lock chamber,and in situ reaction cell.The preparation chamber was equipped with setups based on the surface science techniques used for standard sample preparation and characterization,including an Ar+sputter gun,Auger electron spectrometer,and a low-energy electron diffractometer.After a well-defined model catalyst was prepared,the sample was transferred to a TPD chamber to investigate the adsorption and desorption of the probe molecule,or to the reaction cell,to measure the catalytic activity.A thermal desorption experiment for methanol on a clean Cu(111)surface was conducted to demonstrate the functionality of the preparation and TPD chambers.Moreover,the repeatability of the in situ reaction cell experiment was verified by CO_(2) hydrogenation on the Ni(110)surface.At a reaction pressure of 800 Torr at 673 K,turnover frequencies for the methanation reaction and reverse water-gas shift reaction were 0.15 and 7.55 Ni atom^(-1) s^(-1),respectively. 展开更多
关键词 Surface science Model catalysts Ultra-high vacuum Temperature-programmed desorption in situ reaction cell
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In Situ Reaction Strengthening and Toughening of B_(4)C/TiSi_(2)Ceramics
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作者 夏涛 涂晓诗 +2 位作者 张帆 ZHANG Jinyong REN Lin 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS CSCD 2023年第1期12-19,共8页
B_(4)C-SiC-TiB_(2)ceramics were prepared by in situ reactive hot-pressing sintering with TiSi_(2)as an additive.The reaction pathways of TiSi_(2)and B_(4)C were investigated.The sintering was found to be a multistep p... B_(4)C-SiC-TiB_(2)ceramics were prepared by in situ reactive hot-pressing sintering with TiSi_(2)as an additive.The reaction pathways of TiSi_(2)and B_(4)C were investigated.The sintering was found to be a multistep process.The reaction started at approximately 1000℃,and TiB_(2)was formed first.Part of Si and C started to react at 1300℃,and the unreacted Si melted at 1400℃to form a liquid phase.TiSi_(2)predominantly affected the intermediate sintering process of B_(4)C and increased the sintering rate.Due to the unique reaction process of TiSi_(2)and B_(4)C,a large number of aggregates composed of SiC and TiB_(2)were generated.The results showed that composite ceramics with the optimal flexural strength of 807 MPa,fracture toughness of 3.2 MPa·m1/2,and hardness of 32 GPa,were obtained when the TiSi_(2)content was 10 wt%. 展开更多
关键词 in situ reaction hot pressing sintering TiSi_(2) B_(4)C composite ceramics reaction mechanism
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Al-Si/Al_2O_3 in situ composite prepared by displacement reaction of CuO/Al system 被引量:3
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作者 Zhang Jing Yu Huashun +1 位作者 Chen Hongmei Min Guanghui 《China Foundry》 SCIE CAS 2010年第1期19-23,共5页
Al2O3 particle-reinforced ZL109 composite was prepared by in situ reaction between CuO and Al2O3 . The microstructure was observed by means of OM, SEM and TEM. The Al2O3 particles in sub-micron sizes distribute unifo... Al2O3 particle-reinforced ZL109 composite was prepared by in situ reaction between CuO and Al2O3 . The microstructure was observed by means of OM, SEM and TEM. The Al2O3 particles in sub-micron sizes distribute uniformly in the matrix, and the Cu displaced from the in situ reaction forms net-like alloy phases with other alloy elements. The hardness and the tensile strength of the composites at room temperature have a slight increase as compared to that of the matrix. However, the tensile strength at 350℃ has reached 90.23 MPa, or 16.92 MPa higher than that of the matrix. The mechanism of the reaction in the CuO/AI system was studied by using of differential scanning calorimetry(DSC) and thermodynamic calculation. The reaction between CuO and Al involves two steps. First, CuO reacts with Al to form Cu20 and Al2O3 at the melting temperature of the matrix alloy, and second, Cu20 reacts with Al to form Cu and Al2O3 at a higher temperature. At ZL109 casting temperature of 750- 780 ℃, the second step can also take place because of the effect of exothermic reaction of the first step. 展开更多
关键词 aluminium matrix composites in situ reaction Al2O3 particles ZL109 CUO
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Reaction procedure of a graphite fiber reinforced Ti-Al composite produced by squeeze casting-in situ reaction 被引量:2
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作者 WU Gaohui LIU Yanmei +2 位作者 XIU Ziyang JIANG Longtao YANG Wenshu 《Rare Metals》 SCIE EI CAS CSCD 2010年第1期98-101,共4页
The in situ reaction procedure and microstructure evolution of a graphite fiber reinforced Ti-Al composite (Grf/Ti-Al) was investigated, and the stability of TiAl3 at high temperature was discussed. As-cast material... The in situ reaction procedure and microstructure evolution of a graphite fiber reinforced Ti-Al composite (Grf/Ti-Al) was investigated, and the stability of TiAl3 at high temperature was discussed. As-cast material was prepared by pressing molten pure aluminum into a preform, which was composed of titanium particles and graphite fibers. The in situ reaction procedure of the as-cast material was investigated by differential scanning calorimetry (DSC), and phases in the products were detected by X-ray diffraction (XRD). Experimental results showed that TiAl3 was formed first. With an increase in temperature, TiC and Al4C3 were observed, but TiAl3 decreased. In the final product, Al2O3 and TiO2 were observed. It was considered that the previous forming TiAl3 decomposed, then TiC precipitated, and subsequently, oxidation resulted in the formation of Al2O3 and TiO2. 展开更多
关键词 inTERMETALLICS titanium aluminide composites microstmcture squeeze casting in situ reaction
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Microstructure and mechanism of in-situ Al_2O_(3(p))/Al nano-composites synthesized by sonochemistry melt reaction 被引量:2
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作者 CHEN Deng-bin ZHAO Yu-tao +2 位作者 ZHU Hai-yan ZHENG Meng CHEN Gang 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2012年第1期36-41,共6页
The Al2O3(p)/Al nano-composites were fabricated from Al-K2ZrF6-Na2B4O7 system by sonochemistry in situ reaction. The fabrication mechanisms, including high intensity ultrasonic influence on microstructures and reinf... The Al2O3(p)/Al nano-composites were fabricated from Al-K2ZrF6-Na2B4O7 system by sonochemistry in situ reaction. The fabrication mechanisms, including high intensity ultrasonic influence on microstructures and reinforcement particles-aluminum matrix interface, were investigated by X-ray diffraction (XRD), scanning electron microscopy (SEM) and transmission electron microscopy (TEM). The XRD results show that the component of the as-prepared composites is Al2O3 reinforcement. The SEM analysis results indicate that Al2O3 particles are uniformly distributed in the aluminum matrix. The TEM results show that the morphologies of Al2O3 particles present in nearly sphere-shape, the sizes are in the range of 20-100 nm, and the interfaces are net and no interfacial outgrowth is observed. Analysis with secondary development Image-J software shows that Al2O3 recoveries are firstly improved and then decreased with increasing ultrasonic power. When the power is 0.4 kW, the distribution is the best, and a maximum number of particles are obtained. The reaction mechanisms were investigated. 展开更多
关键词 SONOCHEMISTRY NANO-COMPOSITES in situ reaction reaction mechanism
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Kinetics and Mechanism of Oxidation Induced Contraction of MgAl2O4 Spinel Carbon Composites Reinforced by Al4C3 in situ Reaction
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作者 YANG Mengyao XIAO Guoqing +4 位作者 YANG Ding'ao YUAN Shouqian ZAO Jizeng ZHAO Wei GAO Song 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2020年第4期778-785,共8页
Kinetics and mechanism of oxidation induced contraction of MgAl2O4 spinel carbon composites reinforced by Al4C3 in situ reaction were researched in air using vertical high temperature thermal dilatometer from 25℃to 1... Kinetics and mechanism of oxidation induced contraction of MgAl2O4 spinel carbon composites reinforced by Al4C3 in situ reaction were researched in air using vertical high temperature thermal dilatometer from 25℃to 1400℃.It is shown that oxidation induced contraction of MgAl2O4 spinel carbon composites reinforced Al4C3 in situ reaction is the common logarithm of oxidation time t and the oxygen partial pressure P inside MgAl2O4 spinel carbon composites reinforced by Al4C3 in situ reaction in air at 1400℃is as follows:P=F(-2.75×10^-4A+2.13×10^-3)lnt.The nonsteady diffusion kinetic equation of O2 at 1400℃inside the composites is as follows:J=De lnt.Acceleration of the total diffusional?flux of oxygen inside the composites at 1400℃is in inverse proportion to the oxidation time.The nonsteady state effective diffusion coefficient De of O2(g)inside the composites decreases in direct proportional to the increase of the amount of metallic aluminium.The method of preventing the oxidation induced contraction of MgAl2O4 spinel carbon composites reinforced by Al4C3 in situ reaction is to increase the amount of Al.The slag erosion index of MgO-Al2O3 spinel carbon composite reinforced by Al4C3 in situ reaction is 0.47 times that of MgO-CaO brick used in the lining above slag line area of a VOD stainless steel-making vessel.HMOR of MgO-Al2O3 spinel carbon composite reinforced by Al4C3 in situ reaction is 26.7 MPa,HMOR of the composite is 3.6 times the same as that of MgO-CaO brick used in the lining above slag line area of a VOD vessel.Its service life is two times as many as that of MgO-CaO brick. 展开更多
关键词 KinETICS mechanism OXIDATION CONTRACTION MgAl2O4 spinel carbon Al4C3 in situ reaction
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ANALYSIS OF THE GROWTH MECHANISM OF TiAl_3 WHISKERS PREPARED BY IN SITU REACTION IN MOLTEN ALUMINUM
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作者 B. Yang YQ. Wang J. Zhang and B.L. Zhou (Institute of Metal Research, Chinese Academy of Sciellces, Shenyang 110015, China Nanchang University, Nanchang 330029, China International Center for Materials Physics, Chinese Academy of Sciences, Shenyang 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1997年第5期403-408,共6页
Some TiAl3 whiskers are found to be produced simultaneously during the formation process of TiB2 Particulates fabricated by in situ reaction in molten aluminum. The thec t of temperature of molten aluminum on the morp... Some TiAl3 whiskers are found to be produced simultaneously during the formation process of TiB2 Particulates fabricated by in situ reaction in molten aluminum. The thec t of temperature of molten aluminum on the morphologies of the TiAl3 whiskers and the growth mechanism of the whiskers are studied in this paper. The results show that the aspect rutio of the TiAl3 whiskers decreases with the increase of the temperoture. The growth of the whiskers is proved to be controlled by a Vapor-LiquidSoltd (VLS) mechanism. The titanium and aluminum atoms in the catalytic droplet,however, have been coofrmed to react with each othen which is dtherent from other whlskcrs growing by a VLS mcchanism where the compostion in the catalytic droplet is a constant. 展开更多
关键词 in situ reaction TiAl_3 whisker MORPHOLOGY growth mechanism
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Effect of Ti/B Additions on the Formation of Al_3 Ti of in situ TiB_2/Al Composites 被引量:3
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作者 Bin Yang Jishan Zhang +1 位作者 Xianjin Duan Shuangchun Hu(State Key Laboratory for Advanced Metals and Materials, University of Science and ’Techno1ogy Beijing, Beding 100083, China) 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 1999年第4期285-288,共4页
A novel technique for fabricating TiB_2/Al composites in molten aluminum was introduced. The formation mechanism of brittleAl,Ti particulates up to 30 m in size produced in the composites was studied and a method of e... A novel technique for fabricating TiB_2/Al composites in molten aluminum was introduced. The formation mechanism of brittleAl,Ti particulates up to 30 m in size produced in the composites was studied and a method of eliminating them was proposed. The resultsshow that (l) the brittle Al,Ti particulates are always present in the composites when the molar ratio of Ti to B 'T,:nB is l:2; and (2) theformation of the brittle Al,Ti phase can be avoided entirely from the final product by using a proper 'T,:nB of l:4 in the Ti-B-Al preforms.In the former case, the tensile elongation of the composite is only 4%, much lower than the value of pure aluminum (20%). In the latercase, the tensile elongation of this composite is 10%, higher than the value of the composite with a lot ofAl,Ti (4%), whereas the ultimatetensile stfength of the former is nearly that of the later. 展开更多
关键词 in situ reaction TiB2 /Al composites Al3Ti phase
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Microstructures and Mechanism of Al_2O_3/Al Composites Fabricated by the Reaction between SiO_2 and Molten Aluminum
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作者 程晓敏 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2003年第3期50-52,共3页
Al 2O 3/Al composite was fabricated by the reaction between SiO 2 and molten aluminum.The microstructures of the composite obtained under different reaction conditions were analyzed. The formation mechanism of the ... Al 2O 3/Al composite was fabricated by the reaction between SiO 2 and molten aluminum.The microstructures of the composite obtained under different reaction conditions were analyzed. The formation mechanism of the composite microstructure was discussed. Results show that the reaction kinetics is influenced remarkably by the reaction temperature, reaction time and the quantity of SiO 2.The morphologies of Al 2O 3 have different features,depending on the reaction temperature.The composite has equiaxed Al 2O 3 grains when materials reacted below 1200℃,and the composite is composed of a large number of fine Al 2O 3 grains and aluminum.The composite has a frame shaped Al 2O 3 microstructure at the reaction temperature of above 1250℃. 展开更多
关键词 Al 2O 3/Al composite in situ reaction vitreous silica MICROSTRUCTURE
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Syntheses, Structures and Interactions with DNA of Two in situ Generated Palladium(Ⅱ) Complexes
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作者 YOU Li-Xin LI Jin-Shi +2 位作者 XIONG Gang WANG Shu-Ju SUN Ya-Guang 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第8期1238-1246,共9页
Two new complexes [Pd(L-phe)2·2H2O] (1) and [Pd(4,4'-dcbpy)(en)·H2O] (2) (L-phe = L-phenylalanine, 4,4'-dcbpy = 2,2'-bipyridyl-4,4'-dicarboxylate, en = ethylenediamine) were synthesized and c... Two new complexes [Pd(L-phe)2·2H2O] (1) and [Pd(4,4'-dcbpy)(en)·H2O] (2) (L-phe = L-phenylalanine, 4,4'-dcbpy = 2,2'-bipyridyl-4,4'-dicarboxylate, en = ethylenediamine) were synthesized and characterized. L-phenylalanine was in situ formed via the hydrolysis of N-(tert-butoxycarbonyl)-L-phenylalanine, and ethylenediamine came from the in situ reaction of piperazine (pip) under hydrothermal conditions. The single-crystal X-ray structure analyses reveal that the Pd(Ⅱ) ion constructs a square planer coordination geometry in complexes 1 and 2, respectively. Complex 1 extends into a 2D layered structure via H-bond interactions and complex 2 connects into a 3D network through hydrogen bonds and 7r-tr stacking interactions. The interactions of 1 and 2 with fish sperm DNA (FS-DNA) were examined via UV-Vis absorption spectra and fluorescence spectroscopy. The cleavage reaction for plasmid DNA has been assayed by agarose gel electrophoresis. The results indicate that two complexes interact with DNA and the insertion is the main binding mode. 展开更多
关键词 crystal structure Pd(II) complex in situ reaction L-phenylalanine
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Preparation of Poly ( L-lactic acid ) / Vermiculites Composites by in situ Copolymerization of Lactic Acid and Hydroxylic Vermiculites
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作者 徐红 刘欢 +2 位作者 马辉 钟毅 毛志平 《Journal of Donghua University(English Edition)》 EI CAS 2012年第4期326-330,共5页
L-lactic acid (L-LA) based copolymer/hydroxylation vermiculites composites (PLLA-co-bis A/HVMTs) were prepared by in situ reaction among L-LA, adipic acid, and hydroxylation lamellar vermiculites (HVMTs) using bisphen... L-lactic acid (L-LA) based copolymer/hydroxylation vermiculites composites (PLLA-co-bis A/HVMTs) were prepared by in situ reaction among L-LA, adipic acid, and hydroxylation lamellar vermiculites (HVMTs) using bisphenol-A epoxy resin as chain extending agent. HVMTs were obtained by sulfuric acid-leaching of lamellar vermiculites (VMTs). The effects of sulfuric acid leaching on the VMTs structure were characterized by X-ray diffraction (XRD), 29Si magic-angle spinning nuclear magnetic resonance(29Si NMR), Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FE-SEM), and thermogravimetric analysis (TGA). FTIR, FE-SEM, and TGA were used to characterize the reaction activity of HVMTs. The results indicated that VMTs with increased hydroxyl groups had been successfully obtained and could react with -COOH of the reaction system. The amount of L-LA based copolymer grafted on the surface of HVMTs was more than 22%. The onset decomposition temperature of L-LA based copolymer grafted on the surface of HVMTs was 30℃ higher than that of free L-LA based copolymer. 展开更多
关键词 L-lactic acid(L-LA) based copolymer vermiculites in situ reaction COMPOSITES
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In Situ High-Temperature Reaction-Induced Local Structural Dynamic Evolution of Single-Atom Pt on Oxide Support 被引量:1
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作者 Dongxu Yan Yanxia Gao +2 位作者 Ming-Yu Qi Hongpeng Jia Yi-Jun Xu 《Precision Chemistry》 2023年第5期299-308,共10页
The dynamic evolution of active site coordination structure during a high-temperature reaction is critically significant but often difficult for the research of efficient single-atom catalysts(SACs).Herein,we for the ... The dynamic evolution of active site coordination structure during a high-temperature reaction is critically significant but often difficult for the research of efficient single-atom catalysts(SACs).Herein,we for the first time report the in situ activation behaviors of the local coordination structure of Pt single atoms(Pt_(1))during the high-temperature oxidation of light alkanes.The distinctly enhanced activity of the catalyst is attributed to the in situ evolved Pt_(1)−oxygen vacancy(Pt_(1)−OV)combination ensemble as an efficient and stable active site.Theoretical calculations reveal that the lattice oxygen adjacent to Pt_(1)and the H dissociated from CH4 constitute the lattice hydroxyl,which is the initial step in the formation of the Pt_(1)−OV combination.Pt_(1)and nearby unsaturated Mn can donate the charge back to O−O to promote the dissociation of O_(2).This work provides molecular-level insight into the in situ reaction-induced evolution of a single-atom coordination environment for designing efficient SACs under harsh conditions. 展开更多
关键词 Pt single atom in situ reaction high temperature coordination structure ALKANE
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Competitive precipitation behavior of hybrid reinforcements in copper matrix composites fabricated by powder metallurgy 被引量:2
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作者 Tao Lan Yi-hui Jiang +2 位作者 Xiao-jun Zhang Fei Cao Shu-hua Liang 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2021年第6期1090-1096,共7页
Copper matrix composites reinforced by in situ-formed hybrid titanium boride whiskers(TiB_(w))and titanium diboride particles(TiB_(2p))were fabricated by powder metallurgy.Microstructural observations showed competiti... Copper matrix composites reinforced by in situ-formed hybrid titanium boride whiskers(TiB_(w))and titanium diboride particles(TiB_(2p))were fabricated by powder metallurgy.Microstructural observations showed competitive precipitation behavior between TiB_(w) and TiB_(2p),where the relative contents of the two reinforcements varied with sintering temperature.Based on thermodynamic and kinetic assessments,the precipitation mechanisms of the hybrid reinforcements were discussed,and the formation of both TiB_(w) and TiB_(2p) from the local melting zone was thermodynamically favored.The precipitation kinetics were mainly controlled by a solid-state diffusion of B atoms.By forming a compact compound layer,in situ reactions were divided into two stages,where Zener growth and Dybkov growth prevailed,respectively.Accordingly,the competitive precipitation behavior was attributed to the transition of the growth model during the reaction process. 展开更多
关键词 metal matrix composite hybrid reinforcement in situ reaction growth kinetics
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Syntheses and Crystal Structures of Cd(Ⅱ) and Ni(Ⅱ) Complexes Containing Flexible Sulfide and Nitrogen Heterocyclic Ligands 被引量:3
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作者 郝晓敏 谷长生 +3 位作者 韩丝银 苗艳丽 李泳 宋文东 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2015年第3期408-416,共9页
Two new coordination polymers [Cd(EBLA)(ip)(H2O)] (1) and [Ni(EBSA) (im)2(H2O)], (2) were synthesized by hydrothermal and solution methods using 2,2'-dithio- salicylicacid (EBSA), lH-imidazo[4,5-f][... Two new coordination polymers [Cd(EBLA)(ip)(H2O)] (1) and [Ni(EBSA) (im)2(H2O)], (2) were synthesized by hydrothermal and solution methods using 2,2'-dithio- salicylicacid (EBSA), lH-imidazo[4,5-f][1,10]phenanthroline (ip), imidazole (im), Cd(NO3)2-4H2O and Ni(NOa)z'6H20. The complexes were characterized by elemental analysis and FT-IR. Meanwhile, the crystal structures, fluorescence properties of complex 1 and thermogravimetrie analysis of complex 2 have been studied. In complex 1, 2,2'-dicarboxydiphenylthioether (EBLA) was prepared with 2,2'-dithiosalicylicacid (EBSA) in situ reaction by hydrothermal method. Complex 1 is a dinuclear structure and Cd2+ is five-coordinated in a distorted trigonal bipyramidal geometry. Complex 2 is a one-dimensional infinite linear chain and Ni2+ is six-coordinated to form a distorted octahedral geometry. Hydrogen bonding and π-π interactions are observed in these complexes. 展开更多
关键词 2 2'-dithiosalicylicacid in situ reaction crystal structure
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Hepatitis C and B Virus Infection in Chinese Patients with Extrahepatic Bile Duct Carcinoma 被引量:1
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作者 CHENMingyi HUANGZhiqiang +3 位作者 CHENLezhen GAOYabing PENGRuiyun WANGDewen 《The Chinese-German Journal of Clinical Oncology》 CAS 2002年第1期21-27,共7页
Objective In China, the incidence of extrahepatic bile duct carcinoma (EBDC) tends to increase over the past decades. The etiology of the noted increase in EBDC is not identified. Approximately, in a half of the overa... Objective In China, the incidence of extrahepatic bile duct carcinoma (EBDC) tends to increase over the past decades. The etiology of the noted increase in EBDC is not identified. Approximately, in a half of the overall Chinese patients with EBDC, the causative factors in the development of EBDC have not been demonstrated.There is a high prevalence of hepatitis C virus (HCV) or hepatitis B virus (HBV) in China, both of which can induce malignant transformation of infected cells and strongly associated with hepatocellular carcinoma (HCC). In this study, EBDC tissues from Chinese patients were examined for the presence of HCV and HBV infection to investigate further the potential causes of EBDC.Methods HCV NS5 protein and HBsAg were detected by labeled streptavidin biotin (LSAB) method; HCV RNA and HBV DNA were detected by in situ polymerase chain reaction (IS-PCR) in formalin fixed, paraffin embedded specimens from 51 Chinese patients with EBDC. HCV RNA and HBV DNA were detected by IS-PCR in 34 Chinese patients with specimens of benign lesions of hepatobiliary tract (control group) .Results In 51 case tissue sections of EBDC, NS5 protein was detected in 14 (27.5%), and HBsAg in 5 (9.8%), HCV RNA in 18 (35.4%) and HBV DNA in 8 (15.9%) .respectively, of which HCV and HBV co-infection was detected in 2 (3.9%). In 34 case tissue sections of the control group, HCV RNA was detected in 2 (5.9 % ), and HBV DNA in 3 (8.8%).Conclusion In this study using standard histochemical and PCR techniques, HCV and HBV genomes and their encoding proteins were detected in the tissues of EBDC. The data show that there is a higher than expected incidence of HCV and HBV presence in EBDC tissues than would be expected on serologic grounds. The detectable rate of HCV RNA in EBDC tissues was significantly higher than in control group (x2 = 9.808, P = 0.002). As a result, this study indicates that there is a correlation between the presence of HCV infection and EBDC, and HCV infection has possible etiologic significance in the development of EBDC in China. While HBV DNA was detected in EBDC tissues with the difference in the detectable rate of HBV, DNA being not significance between EBDC tissues and the control group (x2 = 0.853, P = 0.356) . Further research is necessary to determine the presence of a causal relationship between HCV/HBV infection and the development of EBDC. 展开更多
关键词 extrahepatic bile duct carcinoma hepatitis C virus hepatitis B virus in situ polymerase chain reaction ETIOLOGY IMMUNO-HISTOCHEMISTRY
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Syntheses, Structures and Fluorescent Property of Two Cd(Ⅱ) 3D Coordination Polymers with Mixed Ligands of Azide and Piperazine Derivatives
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作者 都凤磊 李志华 +1 位作者 林平 杜少武 《Chinese Journal of Structural Chemistry》 SCIE CAS CSCD 2012年第11期1657-1661,共5页
Two new coordination polymers, [Cd(N3)2(Baep)l/2]n (1) and [Cd2(N3)4(CH3OH)(Bapp)I/.2]n (2) (Baep = 1,4-bis(2-aminoethyl)piperazine, Bapp = 1,4-bis(3-aminopropyl)piperazine) were synthesized. The c... Two new coordination polymers, [Cd(N3)2(Baep)l/2]n (1) and [Cd2(N3)4(CH3OH)(Bapp)I/.2]n (2) (Baep = 1,4-bis(2-aminoethyl)piperazine, Bapp = 1,4-bis(3-aminopropyl)piperazine) were synthesized. The crystal of 1 is of monoclinic system, space group P21/c with a = 9.341(7), b = 11.677(9), c = 8.195(6) A, fl = 93.925(13), V= 891.8(11) A3, Z= 4, μ(MoKa) = 2.42 mm-1, Mr = 280.58, Dc = 2.090 g/cm3, the final R = 0.0297 and wR = 0.0720. The crystal of 2 is of triclinic system, space group PI with a = 9.121(5), b = 9.666(5), c = 10.250(6) A, a = 72.91(2), β= 77.10(2), V = 73.95(2)°, V = 820.0(8)°, Z = 2,μ(MoKa) = 2.62 mm-1, Mr= 522.10, Dc = 2.114 g/cm3, the final R = 0.0251 and wR = 0.0632. Single-crystal X-ray diffraction studies reveal that 1 is a 3D structure based on a dinuclear unit {Cd2(N3)a(Baep)}, in which the Baep ligands formed in situ display two different bridging modes. Compound 2 also has a 3D structure based on a tetranuclear cluster {Cda(N3)8(CH3OH)2(Bapp)}, in which the azido anions exhibit four different bridging modes (μ-1,1, μ-1,3, μ-l,l,1 and μ-1,1,3). The thermal stability and fluorescent property of 1 and 2 have also been investigated. 展开更多
关键词 cadmium azide piperazine derivatives in situ reaction FLUORESCENCE
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MECHANISM OF TiC FORMATION IN LIQUID ALUMINIUM
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作者 W.H. Jiang W.D. Pan and G.H. Song(Dept. of Metal Materials Engineering, Shenyang Polytechnic University, Shenyang 110023, ChinaC. Badini) 《Acta Metallurgica Sinica(English Letters)》 SCIE EI CAS CSCD 1997年第2期141-144,共4页
The mechanism of in situ formation of TiC phase in liquid aluminium during the contact reaction was studied in the present work. The results show that TiC phase forms through two reactions, i.e., 3Al+Ti→Al3 Ti and A... The mechanism of in situ formation of TiC phase in liquid aluminium during the contact reaction was studied in the present work. The results show that TiC phase forms through two reactions, i.e., 3Al+Ti→Al3 Ti and Al3 Ti+C→TiC+3Al. Itis proposed that aluminium acts as a catalyst activating the reaction of TiC formation. 展开更多
关键词 in situ reaction TiC/Al composite MECHANISM
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Investigation on Hepatitis C and B Virus Infection in Carcinoma of the extrahepatic bile duct in CHINA
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作者 陈明易 黄志强 +3 位作者 陈乐真 高亚兵 彭瑞云 王德文 《Chinese Journal of Cancer Research》 SCIE CAS CSCD 2000年第3期12-18,共7页
Objective: The incidence of carcinoma of extrahepatic bile duct tends to increase during recent decade in China, but its cause is unclear. This study is to investigate the hepatitis C virus (HCV) and Hepatitis B virus... Objective: The incidence of carcinoma of extrahepatic bile duct tends to increase during recent decade in China, but its cause is unclear. This study is to investigate the hepatitis C virus (HCV) and Hepatitis B virus (HBV) infection in the tissues of carcinoma of extrahepatic bile duct and study their correlation. Methods: HCV RNA and HBV DNA was detected by in situ polymerase chain reaction (IS-PCR) in sections of 51 cases of carcinoma of extrahepatic bile duct and 34 cases of control group. Results: Of 51 carcinoma of extrahepatic bile duct, HCV RNA was detected in 18 (35.4%), HBV DNA in 8 (15.9%). In 34 cases of control group, HCV RNA was detected in 2 (5.9%), and HBV DNA in 3 (8.8%). Conclusion:The prevalence of hepatitis C and B viralinfection in the tissues of carcinoma of extrahepatic bile duct was significantly higher than in control group. The findings suggest a correlation between HCV, HBV infection and carcinoma of extrahepatic bile duct, inferring HCV and HBV might be involved in the development of carcinoma of extrahepatic bile duct. 展开更多
关键词 Hepatitis C virus Hepatitis B virus Carcinoma of extrahepatic bile duct in situ polymerase chain reaction
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Reaction Processes of the Titanium Matrix Composites Fabricated from Ti-Al-B2O3 System
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作者 崔涛 YU zhuli 朱和国 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2017年第3期650-653,共4页
Titanium matrix composites reinforced with a-Al2O3 and TiB2 particles were fabricated by in situ synthesis from a Ti-Al-B2O3 system. The reaction processes and microstructure were analyzed by using differential scanni... Titanium matrix composites reinforced with a-Al2O3 and TiB2 particles were fabricated by in situ synthesis from a Ti-Al-B2O3 system. The reaction processes and microstructure were analyzed by using differential scanning calorimetry(DSC), scanning electron microscopy(SEM) and X-ray diffraction(XRD). The results showed that the reactions in the Ti-Al-B2O3 system can occur spontaneously and consist of three steps: 1) 15 Al + 7B2O3 → 7α-Al2O3 + AlB12 + 2B; 2) 14 B + 2Al → AlB12 + AlB2 and 3) 7Ti + AlB(12) + AlB2 → 7TiB2 + 2Al. The final reinforcements were composed of α-Al2O3 and TiB2 particles, which were uniformly distributed in the titanium matrix. 展开更多
关键词 titanium matrix composites in situ reaction differential scanning calorimetry(DSC) scanning electron microscopy(SEM) X-ray diffraction(XRD)
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Effect of electroacupuncture on the mRNA and protein expression of Rho-A and Rho-associated kinase Ⅱ in spinal cord injury rats 被引量:9
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作者 You-jiang Min Li-li-qiang Ding +5 位作者 Li-hong Cheng Wei-ping Xiao Xing-wei He Hui Zhang Zhi-yun Min Jia Pei 《Neural Regeneration Research》 SCIE CAS CSCD 2017年第2期276-282,共7页
Electroacupuncture is beneficial for the recovery of spinal cord injury, but the underlying mechanism is unclear. The Rho/Rho-associated kinase(ROCK) signaling pathway regulates the actin cytoskeleton by controlling... Electroacupuncture is beneficial for the recovery of spinal cord injury, but the underlying mechanism is unclear. The Rho/Rho-associated kinase(ROCK) signaling pathway regulates the actin cytoskeleton by controlling the adhesive and migratory behaviors of cells that could inhibit neurite regrowth after neural injury and consequently hinder the recovery from spinal cord injury. Therefore, we hypothesized electroacupuncture could affect the Rho/ROCK signaling pathway to promote the recovery of spinal cord injury. In our experiments, the spinal cord injury in adult Sprague-Dawley rats was caused by an impact device. Those rats were subjected to electroacupuncture at Yaoyangguan(GV3), Dazhui(GV14), Zusanli(ST36) and Ciliao(BL32) and/or monosialoganglioside treatment. Behavioral scores revealed that the hindlimb motor functions improved with those treatments. Real-time quantitative polymerase chain reaction, fluorescence in situ hybridization and western blot assay showed that electroacupuncture suppressed the m RNA and protein expression of Rho-A and Rho-associated kinase Ⅱ(ROCKⅡ) of injured spinal cord. Although monosialoganglioside promoted the recovery of hindlimb motor function, monosialoganglioside did not affect the expression of Rho-A and ROCKⅡ. However, electroacupuncture combined with monosialoganglioside did not further improve the motor function or suppress the expression of Rho-A and ROCKⅡ. Our data suggested that the electroacupuncture could specifically inhibit the activation of the Rho/ROCK signaling pathway thus partially contributing to the repair of injured spinal cord. Monosialoganglioside could promote the motor function but did not suppress expression of Rho A and ROCKⅡ. There was no synergistic effect of electroacupuncture combined with monosialoganglioside. 展开更多
关键词 nerve regeneration spinal cord injury electroacupuncture Rho/Rho-associated kinase signaling pathway monosialoganglioside motor function cytoskeleton real-time quantitative polymerase chain reaction western blot assay hybridization in situ neural regeneration
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