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Multiwalled Carbon Nanotubes Reinforced Alumina Composites

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Journal of wuhan university of technology(Materials science) 2011年第6期26卷 1171-1173页

作者：张金咏 State Key Laboratory of Advanced technology for Materials Synthesis and Processing Wuhan University of Technology

1wt% multiwalled carbon nanotube （MWNTs） reinforced alumina composites was sintered to full density by spark plasma sintering. And pure alumina and graphite/alumina composites were also prepared by the same way for comparison. Indentation and single edge V-notched beam （SEVNB） toughness were measured respectively. The experimental results show that MWNTs could not improve toughness of alumina too much as that once expected. And SEVNB toughness was more valid than indentation toughness.

关键词： MWNT alumina toughness

DFT and TDDFT investigations on the ground and excited states for polynuclear platinum(II) complexes containing the rigid phenylacetylide ligand

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science china Chemistry 2007年第5期50卷 599-606页

作者： ZHOU Xin1, PAN QingJiang2, LI MingXia1,2, ZHANG HongXing1 & Tang AuChin1 1 State Key Laboratory of Theoretical and Computational Chemistry, Institute of Theoretical Chemistry, Jilin university, Changchun 130023, china 2 School of Chemistry and Materials science, Heilongjiang university, Harbin 150080, china State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry Jilin University Changchun China School of Chemistry and Materials science Heilongjiang University Harbin China

We have studied the ground and excited states of the three dendriticpolynuclear Pt(ll) complexes 1-[Cl(PH3)2PtC ident to C]-3,5-[HC ident to C]C6H3 (1),1,3-[CI(PH3)2PtCident to C]2-5-[HC ident to C]C6H3 (2),and 1,3,5-[CI(PH3)2-PtC ident to C]3C6H3 (3),by using theB3LYP and UB3LYP methods,*** approach with the PCM model was performed to predict theemission spectra properties of 1-3 in CH2Cl2 *** first predicted the excited-stategeometries for the three *** the change of the number of Pt(ll) atom,1-3 show thedifferent geometry structures in both the ground and excited states;furthermore,the increase of themetal density from 1 to 3 results in the red shift of the lowest-energy emissions along *** luminescent properties of 1 are somewhat different from those of 2 and *** emissionproperties of 2 and 3 are richer than *** conclusion can give a good support for designing thehigh efficient luminescent materials.

关键词： excited state luminescence dendritic platinum(ll) complexes DFT TDDFT

Principle of Interaction between Plastic Volumetric and Shear Strains and the Constitutive Model for Geotechnical Materials

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工程科学（英文版） 2007年第2期5卷 129-138页

作者： Wang Jingtao(1.Department of Architectural Engineering, Xinyang Normal university, Xinyang 464000, Henan, china 2.School of Civil Engineering and Mechanics, huazhong university of science and technology, wuhan 430074, china)

Here is proposed the principle of interaction between plastic volumetric and shear strains, revealing the main origin of generating the complexity and variety of deformations for geotechnical materials. Here are also explained the manners of the interaction between plastic volumetric and shear strains and the conditions of generating shear dilatancy. It is demonstrated that dependency of the stress path exists and is a combination of effects of this interaction. According to this principle, it is theoretically proved that the space critical state line exists, and is unique and independent of the stress history. Based on this principle, the constitutive models that are able completely and accurately to characterize the basic behavior features for geotechnical materials have been constructed within the framework of thermodynamics. What is determined is a general expression of the constitutive relation as well as the inequality of the dissipative potential increment for obeying the second law of thermodynamics.

关键词： interaction between volumetric and shear strains constitutive model for rock and soil dependency of stress path pressure-sensitivity shear dilatancy

Detection of *** DNA in gastric epithelial cells by in situ hybridization

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World Journal of Gastroenterology 2002年第2期8卷 305-307页

作者： Xin-Liang Lu Ke-Da Oian Xun-Qiu Tang Yong-Liang Zhu Qin Du,Department of Digestive Diseases,Second Affiliated hospital,Zhejiang university medical college,Hangzhou 310009,Zhejiang Province,china Department of Digestive Diseases Second Affiliated Hospital Zhejiang University Medical College Hangzhou 310009 Zhejiang Province China. luxl@***

AIM: To investigate the presence of *** DNA within gastric epithelial cells in patients with *** infection and its possible carcinogenic mechanism. METHODS: Total 112 patients, with pathologically confirmed chronic superficial gastritis, chronic atrophic gastritis, intestinal metaplasia, atypical hyperplasia or gastric cancer were studied. Among them, 28 were *** negative and 84 *** positive. *** DNA in gastric epithelial cells was detected by GenPoint catalyzed signal amplification system for in situ hybridization. RESULTS: In the *** positive group, zero out of 24 chronic superficial gastritis (0.0%), four out of 25 precancerous changes (16.0%) and thirteen out of 35 gastric cancers (37.1%) showed *** DNA in the nucleus of gastric epithelial cells, the positive rates of *** DNA in the nucleus of gastric epithelial cells were progressively increased in chronic superficial gastritis, precancerous changes and gastric cancer groups (chi(2)=12.56, P=0.002); One out of 24 chronic superficial gastritis (4.2%), eleven out of 25 precancerous changes (44.0%) and thirteen out of 35 gastric cancers (37.1%) showed *** DNA in the cytoplasm of gastric epithelial cells (chi(2)=10.86, P=0.004). In the *** negative group, only one patient with gastric cancer was found *** DNA in the nucleus of gastric epithelial cells; Only two patients, one patient with precancerous changes and another with gastric cancer, showed *** DNA in the cytoplasm of gastric epithelial cells. Furthermore, *** DNA must have been in the cytoplasm as long as it existed in the nucleus of gastric epithelial cells. CONCLUSION: *** DNA exists both in the nucleus and the cytoplasm of gastric epithelial cells in patients with *** infections. The pathological progression from chronic superficial gastritis, precancerous changes to gastric cancer is associated with higher positive rates of *** DNA presence in the nucleus of gastric epitheli

关键词： In Situ Hybridization DNA, Bacterial Epithelial Cells Gastric Mucosa Helicobacter Infections Helicobacter pylori purification Humans Stomach Diseases

Murine fertilized ovum, blastomere and morula cells lacking SP phenotype

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science china(Life sciences) 2007年第6期50卷 762-765页

作者： XU YiXin1, HE ZhiYing2, ZHU HaiYing2, CHEN XueSong2, LI JianXiu2, ZHANG HongXia2, PAN XingHua3 & HU YiPing2 1 ChangZheng hospital, affiliated to Second Military medical university, Shanghai 200003, china 2 Department of Cell Biology, Second Military medical university, Shanghai 200433, china 3 Department of Genetics, Yale university School of Medicine, New Haven, CT 06519, USA ChangZheng hospital affiliated to Second Military Medical University Shanghai China Department of Cell Biology Second Military Medical University Shanghai China Department of Genetics Yale University School of Medicine New Haven USA

In the field of stem cell research, SP (side population) phenotype is used to define the property that cells maintain a high efflux capability for some fluorescent dye, such as Hoechst 33342. Recently, many researches proposed that SP phenotype is a phenotype shared by some stem cells; some progenitor cells,; that SP phenotype is regarded as a candidate purification marker for stem cells. In this research, murine fertilized ova (including conjugate; single nucleus fertilized ova), 2-cell stage; 8-cell stage blastomeres, morulas; blastocysts were isolated; directly stained by Hoechst 33342 dye. The results show that fertilized ovum, blastomere; morula cells do not demonstrate any ability to efflux the dye. However, the inner cell mass (ICM) cells of blastocyst exhibit SP phenotype, which is consistent with the result of embryonic stem cells (ESCs) in vitro. These results indicate that the SP phenotype of ICM-derived ESCs is an intrinsic property; independent of the culture condition in vitro,; that SP phenotype is one of the characteristics of at least some pluripotent stem cells, but is not shared by totipotent stem cells. In addition, the result that the SP phenotype of ICM cells disappeared when the inhibitor verapamil was added into medium implies that the SP phenotype is directly associated with ABCG2. These results suggest that not all the stem cells demonstrate SP phenotype,; that SP phenotype might act as a purification marker for partial stem cells such as some pluripotent embryonic stem cells; multipotent adult stem cells, but not for all stem cells exampled by the totipotent stem cells in the very early stage of mouse embryos.

关键词： ABCG2/BCRP, stem cell, fertilized ovum, blastocyst, inner cell mass, embryonic stem cell, SP phenotype

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天然气井油管腐蚀沟槽的形成原因

天然气工业 2002年第1期22卷 95-97页

作者：罗逸华中科技大学化学系

借助X—衍射分析、X—光电子能谱分析、扫描电镜能谱分析和电子探针分析等表面分析及腐蚀试验方法 ,对气井油管腐蚀沟槽的形成原因及特点进行了分析。实验结果证实 ,N80油管钢抗CO2 腐蚀的能力仅为A3钢的四分之一 ,并且其中的MnS等夹杂... 详细信息

借助X—衍射分析、X—光电子能谱分析、扫描电镜能谱分析和电子探针分析等表面分析及腐蚀试验方法 ,对气井油管腐蚀沟槽的形成原因及特点进行了分析。实验结果证实 ,N80油管钢抗CO2 腐蚀的能力仅为A3钢的四分之一 ,并且其中的MnS等夹杂物可与基体铁构成腐蚀原电池并诱发晶间腐蚀 ,从而成为沟槽发生源。它在高压酸性碳酸气体的作用下产生的非均匀性点 (坑 )腐蚀是沟槽得以产生与拓展的根本原因。高压天然气流对管壁的破坏作用服从流体动力学的冲蚀规律 ,这种携带地层岩土微粒的高压气流对管壁的撞击作用是促使蚀点沿流体方向逐渐扩展并形成狭长沟槽的原动力。因此 ,CO2 腐蚀及高速气流撞击磨蚀是造成沟槽产生和扩展的主要原因。

关键词：天然气气井油管腐蚀二氧化碳腐蚀冲蚀形成原因

Influences of Laser Powers on Microstructure and Properties of the Al-Si/Al+Al_2O_3 Coating on the AZ91D Magnesium Alloy

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稀有金属材料与工程 2011年第S4期40卷 226-230页

作者： Qian Jiangang1,Zhang Jiaxiang1,2,Li Shuqing2,Wang Chun2,Gong Shuili21School of Chemistry and Environment,Beijing university of Aeronautics and Astronautics,Beijing 100191,china2science and technology on Power Beam Processes Laboratory,Avic Beijing Aeronautical Manufacturing technology Research Institute,Beijing 100024,china Beijing Univ Aeronaut & Astronaut Sch Chem & Environm Beijing 100191 Peoples R China Avic Beijing Aeronaut Mfg Technol Res Inst Sci & Technol Power Beam Proc Lab Beijing 100024 Peoples R China

An Al-Si/Al+Al2O3 coating was prepared on an AZ91D Mg alloy substrate by laser cladding of the plasma-sprayed coating.X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used to identify the phases and to study the morphology,*** adhesion strength and the porosity ratio of the coating were measured by using a tensile testing machine and an optical microscope (OM),*** microhardness was measured using a micro Vickers hardness *** results show that after laser cladding,the adhesion strength of the coating increased from 10.78 to 25.17 *** the laser power was 1400W,the metastable γ-Al2O3 phase in the coating transformed completely into the stable α-Al2O3 *** with the increase of the laser power,the porosity ratio of the coating *** when the laser power was over 1400W,the porosity ratio *** microhardness of the surface was the hardest which was improved from HV0.05125 to *** larger the power of the laser was,the harder the coating *** when the power was 1600W,the microhardness increased slightly,even the microhardness of the internal decreased.

关键词： laser-clad plasma-sprayed magnesium alloy Al-Si/Al+Al2O3 coating

CONTROLLED/"LIVING" RADICAL POLYMERIZATION OF STYRENE IN AN AQUEOUS DISPERSION SYSTEM

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Chinese Journal of Polymer science 2002年第5期20卷 445-451页

作者： Bin Zhang Zhao-bin Zhang Xiao-long Wan Chun-pu Hu Sheng-kang Ying Lab of Living Polymerization, East china university of science and technology.Shanghai 200237,china Lab of Living Polymerization East China University of Science and Technology 上海 200237

Atom transfer radical polymerization (ATRP) of styrene catalyzed by cuprous (CuX)/1,10-phenanthroline (Phen) and CuX/CuX2/Phen was conducted in an aqueous dispersed system. A stable latex was obtained by using ionic surfactant sodium lauryl sulfonate (SLS) or composite surfactants, such as SLS/polyoxyethylene nonyl phenyl ether (OP-10), SLS/hexadecanol and SLS/OP-10/hexadecanol, Among which SLS and SLS/OP-10/hexadecanol systems established better dispersed effect during the polymerization, It was found that Phen was a more suitable ligand than N,N,N',N',N'-pentamethyldiethylenetriamine (PMDETA) to maintain an appropriate equilibrium of the activator Cu(I) and the deactivator Cu(II) between the organic phase and the water phase, The effect of several initiators (such as EBiB, CCl4 and 1-PEBr) and the temperature on such a kind of ATRP system was also observed. The number-average molar mass (M-n) of polystyrene (PS) increased with the conversion and the molar mass distribution (M-w/M-n) remained narrow. These experimental data show that the polymerization could be controlled except for the quick increase of monomer conversion and the number-average molar mass of PS in the initial stage of polymerization. Furthermore, the initiator efficiency was found to be low (similar to57%) in CuX/Phen catalyzed system. To overcome this problem, Cu(II)X-2 (20 mol%-50 mol% based on CuX) was introduced into the polymerization system. In this case, higher initiator efficiency (60%-90%), low M-w/M-n of PS (as low as 1.08) were achieved and the molar masses of the PS fit with the theoretical ones.

关键词： controlled/'living' radical polymerization polystyrene water dispersed polymerization 1,10-Phenanthroline

Multipliers on Dirichlet Type Spaces

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Acta Mathematica Sinica,English Series 2001年第2期17卷 263-272页

作者： Peng Yan HU Department of Mathematics. Normal college of Shenzhen university. Shenzhen. Guangdong 518060. P. R. china Ji Huai SHI Department of Mathematics. university of science and technology of china. Hefei. Anhui 230026, P. R. china Department of Mathematics Normal College of Shenzhen University Shenzhen Guangdong 518060 P. R. China Department of Mathematics University of Science and Technology of China Hefei Anhui 230026 P. R. China

In this paper, we characterize the pointwise multiplier space M(D_τ, D_μ) of Dirichlet type spaces in the unit ball of C^n for the values of τ, μ in three cases: (i)τn. and construct two functions to show that M... 详细信息

关键词： Dirichlet space Pointwise multiplier Holomorphic function