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Deposition of CrN Coatings by Filtered Cathodic Vacuum Arc

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Deposition of CrN Coatings by Filtered Cathodic Vacuum Arc

Fifth International Conference on Surface Engineering

作者： j.L.Mo,M.h.Zhu,j.An,h.Sun,Y.X.Leng,N.huang Key Laboratory of Advanced Technologies of Materials,Ministry of Education,Southwest jiaotong University,Chengdu 610031,China

CrN coatings were deposited on cemented carbide substrates by filtered cathodic vacuum arc technique(FCVA).The effect of different deposition parameters:nitrogen partial pressure,substrate-bias voltage and preheating of the specimens,on the structural and mechanical properties of the coatings was investigated.X-ray diffraction analysis was used to determine the structure and the composition of the *** tribological behaviour and wear properties of the coatings against Si3N4 ball with diameter of 4 mm were studied under reciprocating sliding *** results showed that a smooth and dense CrN coating with best properties can be obtained provided a pure Cr interlayer was *** optimal deposition parameters were the nitrogen partial pressure of 0.1 Pa,substrate-bias voltage of-100 ***,preheating of the substrate was not good for improving the properties of the *** FCVA CrN coating showed high hardness and good wear resistance,which was probably attributed to its smooth surface and dense ***,the coating flaked off at relatively high normal load(20 N).The wear mechanism of the CrN coatings was a combination of abrasion and oxidation.

关键词： PVD Filtered cathodic vacuum arc technique CrN coating Tribological properties

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硫酸生产是否真的需要催化剂

化工粉体工程设计 1994年第1X期 40-42,39页

作者： j.j.h.Masseling D.Netzer 郭峰

实际上,所有的硫酸生产均以使用催化剂促进二氧化硫氧化为三氧化硫的接触法为基础。本文叙述了一个用气体反复循环以补偿每次转化较少的非催化系统。

关键词：三氧化硫硫酸生产吸收塔焚硫炉硫酸装置催化剂床层弛放气反应热二氧化硫气体

Drought Resistant Rice: an Integrated Crop Improvement Strategy

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分子植物育种 2007年第2期5卷 211-212页

作者： R. Serraj j. Cairns G. Atlin A. Kumar j. Bernier D. Brar K. McNally h. Leung P. herve R. Bruskiewich.j. Bennett International Rice Research Institute DAPO 7777 Metro Manila Philippines

Rice physiological sensitivity to drought and its impact on crop productivity in water-limited environments are well-documented (O'Toole, 2004). however, rice yields in drought-prone rainfed lowlands and most

关键词：干旱耐受能力稻子种植

What happens in the smooth muscle cell for lower vasoreactivity in severe shock

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中国病理生理杂志 2001年第8期 66-67页

作者： Zhao KS Liu j Yang GY Department of Pathophysiology First Military Medical University Guangzhou 510515 China

It is very difficult for doctor to treat patient with persistent hypotension in the late stage of shock. The aim of present study was to elucidate the reason for lower vasoreactivity in severe shock. Irreversible hemorrhagic shock of rat was reproduced and the vasoreactivity of arteriole in spinotrapezius muscle to norepinephrine (NE) was measured. The resting membrane potential of isolated arterial strips was detected with a microelectrode. The effect of NO on the membrane potential and intracellular ［Ca2＋］i level in isolated arteriolar smooth muscle cells (ASMCs) was determined with fluorescent probes under confocal microscope. KATP channel of ASMCs was measured with patch clamp method. It was shown that membrane hyperpolarization appeared in arteroles 2 h post hemorrhage, while the resting potential was increased from (-36.9±6.3) mV of control value to (-51.0±9.1) mV with the NE threshold increased to 15 times more than preshock value. The hyperpolarization of ASMCs was closely related to vascular hyporeactivity (correlation coefficient 0.96, P＜0.01). The hyperpolarization was enhanced by lack of ATP, increase in h＋，and OONO- in ASMCs. Single KATP channel conducatance, mean open time and open probability was increased in ASMCs, and the increased ［Ca2＋］i level of ASMCs stimulated by NE was reduced to 50% of normal value. The vasoreactivity, blood pressure and survival rate could be improved by the treatment of glybenclamide and NahCO3. The study indicates that hyperpolarization of ASMCs is a major reason for lower vasoreactivity in severe shock, since it inhibits the voltage dependent Ca2＋ channel (POC) with the reduction of NE stimulated ［Ca2＋］i increase. The decrease in ATP and increase in h+, and OONO- in ASMCs involves in the activation of KATP channel, leading to the ASMCs hyperpolarization.

关键词： cell

Neutron Distribution Measurements For high-Precision NAA

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Neutron Distribution Measurements For High-Precision NAA

Rac1 regulates the release of Weibel-Palade Bodies in human aortic endothelial cells

作者： K.Takamiya M.Takimoto S.Shibata R.Okumura Y.Nakano j.h.Moon S.h.Kim Korea Atomic Energy Research Institute

INTRODUCTION:A neutron flux is important parameter in neutron activation analysis,radioisotope production and other neutron irradiation *** the case of neutron activation analysis,the analytical accuracy depends on the estimation of neutron flux at irradiations. In order to neglect a neutron flux parameter in the analytical determination,a standard comparison method is *** this method,standard materials are irradiated with analytical samples at a *** only one standard material is irradiated in many cases even through many

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Chinese Medical journal 2004年第8期117卷 1143-1150页

作者：杨水祥闫娟 Shailesh S.Deshpande Kaikobad Irani Charles j.Lowenstein Cardiovascular Center Tongren hospital Capital University of Medical SciencesBeijing100730China Division of Cardiology Department of Medicine Department of PathologyJohns Hopkins UniversitySchool of MedicineBaltimoreMaryland 21205USA

Background The release of Weibel-Palade Bodies (WPB) is a form of endothelial cell activation But the signal transduction pathway leading to WPB release is not yet defined We hypothesized that small G-protein rac1 and reactive oxygen species (ROS) mediate the ligand induced release of Weibel-Palade Bodies Methods We tested this hypothesis by using wild-type and mutant adenoviral rac1 expression vectors, and by manipulating the production and destruction of superoxide and hydrogen peroxide in human aortic endothelial cells (hAEC) Kh*2/5DResults Thrombin (1 0 Unit, 30 min) induced the increase of WPB release by 3 7-fold in hAEC, and that h 2O 2 (0 1 mmol/L, 30 min) induced by 4 5-fold These results correlated with thrombin-stimulated activation of rac-GTP binding activity by 3 5-fold, and increase of ROS production by 3 4-fold The dominant negative adenoviral rac-N17 gene transfer dramatically inhibited the release of WPB by 64 2% (control) and 77 3% (thrombin-stimulation), and decreased ROS production by 65 5% (control) and 83 6% (thrombin-stimulation) compared with non-infected cells, respectively Anti-oxidants, catalase and N-acetyl-cysteine significantly decreased the release of WPB by 34% and 79% in control cells, and further decreased by 63 6% and 46 7% in rac-N17 transferred cells compared with non-infected cells We also confirmed that rac1 was located upstream of ROS in the WPB release pathway Kh*2/5DConclusions Small G-protein rac1 medicates ligand-induced release of Weibel-Palade Bodies in human aortic endothelial cells, and the signal pathway of WPB release is a rac1-dependent ROS regulating mechanism

关键词： Weibel-Palade Bodies von Willebrand factor P-selectin rac thrombin exocytosis reactive oxygen species

Depositional and Diagenetic Controls on Sandstone Reservoirs with Low Porosity and Low Permeability in the Eastern Sulige Gas Field, China

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Acta Geologica Sinica(English Edition) 2014年第5期88卷 1513-1534页

作者： YANG Renchao FAN Aiping A.j.van LOON hAN Zuozhen WANG Xiuping Shandong Provincial Key Laboratory of Depositional Mineralization & Sedimentary Minerals College of Earth Science and Engineering Shandong University of Science and Technology Institute of Geology Adam Mickiewicz UniversityMaków Polnych 16 61-606 Poznan Poland

In order to determine the genesis and the factors that control the low-porosity and low- permeability sandstone reservoirs in the eastern Sulige Gas Field in the Ordos Basin, systematic studies on the sedimentary facies and diagenesis were conducted by means of analysis of cores, thin sections, fluid inclusions, X-ray diffraction, cathode luminescence and scanning electron microscope. It was found that the sand bodies of the major gas reservoirs in the Shan1 section （P1S1） and the he8 section （P2h8） were formed during the Permian as sedimentary facies such as braided-channel bars, braided-river channels and point bars of a meandering river. Four types of diagenetic facies developed subsequently： in order from the best to the poorest properties these are type A （weak compaction, early calcite cement-chlorite film facies）, type B （moderate compaction, quartz overgrowth-feldspar corrosion-kaolinite filling facies）, type C （strong compaction, late calcite cement-quartz corrosion facies） and type D （matrix filling and strong compaction facies）. This diagenesis is undoubtedly the main reason for the poor reservoir properties of sandstone reservoirs, but the sedimentary facies are the underlying factors that greatly affect the diagenesis and thus the reservoir performance. Favorable diagenetic facies developed mainly in relatively small lithofacies such as braided-river channels, channel bars and point bars. The vertical distribution of the physical properties and the diagenetic facies of the reservoirs are related to the stratigraphic succession. Most of the sandstones between mudstones and thin beds of sandstone are unfavorable diagenetic facies. Analyses indicate that siliceous cementation can hardly be stopped by hydrocarbon filling. Authigenic chlorite could hardly protect the primary porosity. It not only occupies pore space, but also blocks pathways through sandstone reservoirs, so that it has significant influence on the permeability. Authigenic chlorite cannot be

关键词： Ordos Basin Sulige Gas Field sandstone reservoir sedimentary facies diagenesis,diagenetic facies

Structure-based protein-protein interaction networks and drug design

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Frontiers of Electrical and Electronic Engineering in China 2013年第3期8卷 183-191页

作者： hammad Naveed jingdong j. han Chinese Academy of Sciences Key Laboratory of Computational Biology Chinese Academy of Sciences-Max Planck PartnerInstitute for Computational Biology Shanghai Institutes for Biological Sciences Chinese Academy of Sciences Shanghai200031 China

Proteins carry out their functions by interacting with other proteins and small molecules, forming a complex interaction network. In this review, we briefly introduce classical graph theory based protein-protein interaction networks. We also describe the commonly used experimental methods to construct these networks, and the insights that can be gained from these networks. We then discuss the recent transition from graph theory based networks to structure based protein-protein interaction networks and the advantages of the latter over the former, using two networks as examples. We further discuss the usefulness of structure based protein-protein interaction networks for drug discovery, with a special emphasis on drug repositioning.

关键词： protein-protein interaction network structure-based drug design drug reposition

Observation of inhomogeneity in congruent LiTaO3 crystal

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Beijing Synchrotron Radiation Facility 2001年第2期 142-144,页

作者： X.B.hu h.D.jiang h.Liu S.S.jiang Q.Li j.Y.Wang C.Q.Zhang B.Ten BeijingSynchrotronRadiationLaboratory InstituteofHighEnergyBeijing100039210093People’sRepublicofChina NationalLaboratoryofSolidStateMicrostructures NanjingUniversityNanjing210093People’sRepubli

The inhomogeneity in a congrunet LiTaO3 crystal has been observed by transmission synchrotron *** extraordinary regions exist in congruent LiTaO3 crystal and they often show diffraction intensity different from that of ordinary regions in synchrotron *** thermal analysis indiates that the Curie temperature of the extraordinary region is lower than that of ordinary region,and the extraordinary region is really a high defect density *** diffraction contrast of the extraordinary region in synchrotron topographs is explained qualitatively by a calculation at the selected wavelength.2001 Published by Elsevier Science B.V.

关键词： LiTaO3晶体钽酸锂晶体同步辐射形貌术结构分析 X射线分析