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Tribological properties of cobalt-based alloy coating with different cobalt contents by electro-spark deposition

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Rare Metals 2013年第1期32卷 40-46页

作者： qi-Feng Jing Ye-fa Tan Engineering Institute of Engineering Corps PLA University of Science & Technology Unit 78649 of PLA

The cobalt-based alloy coating with different Co contents was deposited on 45 steel by electro-spark deposition with the self-made electrode. The coating has a compact and uniform microstructure with low porosity and no visible microcracks. When Co content increases grad- ually, oxygen content of coating samples 1-5 decreases first and then increases in the range of 2.52 wt%-3.05 wt%; sample 3 has the lowest oxygen content of 2.52 %. Mi- crohardness of the coating is improved remarkably com- pared with the substrate （HV 230.18）. With Co content increasing, microhardness of the coating samples 1-5 first rises slightly and then declines rapidly in the range of HV 580.61-1052.33. Sample 3 gets the maximum of HV 1052.33, which is about 4.6 times that of the substrate. The coating presents excellent wear resistance, which first increases and then decreases when Co content increases. Sample 3 shows the best wear resistance of about 6.4 times that of the substrate. Main wear mechanism of the coating is abrasive wear and fatigue wear, along with oxidation wear under high speed or heavy load conditions.

关键词： Electro-spark deposition Cobalt Content Microstructure Wear resistance Wear mechanism

Intermolecular Stetter reaction of aromatic aldehydes with(E)-(2-nitrovinyl)cyclohexane induced by N-heterocyclic carbene and thiourea

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Chinese Chemical Letters 2016年第7期27卷 1032-1035页

作者： qing-fang Cheng Jing-Wen Wang qi-fa Wang zhou Liu Jiangsu Key Laboratory of Marine Biotechnology Huaihai Institute of Technology School of Chemical Engineering Huaihai Institute of Technology

Intermolecular Stetter reaction of aromatic aldehydes with（E）-（2-nitrovinyl）cyclohexane catalyzed by thiazolium A has been *** reaction rate and efficiency are profoundly impacted by the presence of thiourea *** r... 详细信息

关键词： Intermolecular Stetter reaction N-heterocyclic carbene Thiourea Thiazolium Nitroalkene β-Nitro ketone

The consensus on liver autotransplantation from an international panel of experts

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Hepatobiliary & Pancreatic Diseases International 2017年第1期16卷 10-16页

作者： qi-fa Ye Norbert Senninger Zhongnan Hospital of Wuhan University Institute of Hepatobiliary Diseases of Wuhan University Transplant Center of Wuhan University Hubei Key Laboratory of Medical Technology on Transplantation Research Center of National Health Ministry on Transplantation Medicine Engineering and Technology The 3rd Xiangya Hospital of Central South University Department of General Surgery University Clinics of Münster

IntroductionMore than 1.0 million patients worldwide are diagnosed with space-occupying lesions in the liver every year, with the number approaching 0.5 million per year in China, and only 20% of the lesions are resectable Due to a lack of available donors, only a limited number of patients underwent allogeneic liver transplantation, the remaining patients simply receive palliative care. Therefore, discovering new options for treating these patients is a high priority. Liver autotransplantation （LAT） is a surgical technique that adopts liver transplantation skills to radically treat spaceoccupying hepatic lesions, benign or malignant,

关键词： The consensus on liver autotransplantation from an international panel of experts

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缺血再灌注损伤对载脂蛋白M表达的影响

苏州大学学报（医学版） 2005年第3期25卷 402-404,408页

作者：许贤林叶启发何小舟张晓膺罗光华朱江 Ning Xu 巢志复华中科技大学同济医学院附属同济医院器官移植研究所湖北武汉430030 苏州大学附属第三医院江苏常州213003 瑞典隆德大学医院临床化学研究所瑞典隆德s22185

目的探讨肝缺血再灌注损伤时肝内载脂蛋白M(apoM)mRNA及血浆apoM的表达。方法将40只健康雄性SD大鼠随机分成5组(每组8只)。假手术组(对照组)进腹后仅分离十二指肠韧带,不阻断血流;IR1组灌注0.5h;IR2组缺血60min后再灌注1.0h;IR3组缺血60... 详细信息

目的探讨肝缺血再灌注损伤时肝内载脂蛋白M(apoM)mRNA及血浆apoM的表达。方法将40只健康雄性SD大鼠随机分成5组(每组8只)。假手术组(对照组)进腹后仅分离十二指肠韧带,不阻断血流;IR1组灌注0.5h;IR2组缺血60min后再灌注1.0h;IR3组缺血60min后再灌注2.0h、IR4缺血60min后再灌注3.0h。在各时间点活杀大鼠,检测血浆谷丙转氨酶(ALT)水平、肝组织病理变化、血浆apoM蛋白及肝组织apoMmRNA。结果血浆ALT的水平随着灌注时间的延长而升高,肝组织损伤随着灌注时间的延长而逐渐加重。肝组织apoMmRNA的表达则先有一过性下降(IR1组),此后随着灌注时间的延长其表达明显增强。血浆apoM蛋白有相同的变化趋势,但其表达的上升有相应的滞后(IR2组)。结论在肝缺血再灌注损伤过程中,肝脏apoMmRNA的表达和血浆蛋白水平有迅速、明显的变化,提示apoM可能具有急性时相反应蛋白的特性。

关键词：缺血再灌注急性时相反应蛋白载脂蛋白M 肝

Embedding Derivatives and Integration Operators on Hardy Type Tent Spaces

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Acta Mathematica Sinica,English Series 2022年第6期38卷 1069-1093页

作者： Mao fa WANG Lv zhou School of Mathematics and Statistics Wuhan UniversityWuhan 430072P.R.China

In this paper,we completely characterize the positive Borel measuresμon the unit ball B_(n)such that the differential type operator R^(m)of order m∈N is bounded from Hardy type tent space HT_(q,α)^(p)(B_(n))into L^(s)(μ)for full range of p,q,s,α.Subsequently,the corresponding compact description of differential type operator R^(m)is also *** an application,we obtain the boundedness and compactness of integration operator J_(g)from HT_(q,α)^(p)(B_(n))toHT_(s,β)^(t)(B_(n)),and the methods used here are adaptable to the Hardy spaces.

关键词： Embedding derivative integration operator Hardy type tent space Carleson measure

Design and Analysis for a Three-Rotational-DOF Flight Simulator of Fighter-Aircraft

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Chinese Journal of Mechanical Engineering 2018年第3期31卷 48-59页

作者： Chang-Chun zhou Yue-fa fang Robot Research Center Beijing Jiaotong University

Most of researchers focused on traditional six degrees of freedom(DOF) Stewart flight simulator,which can not be adaptive in fighter?aircraft flight simulator. A three rotational DOF flight simulator of fighter?aircraft based on dou?ble parallel manipulator and hybrid structure is presented. The flight simulator is composed of two identical 3?RRS(revolute?revolute?spherical) spherical parallel manipulators and one cabin,called Twins. The cabin has an additional independent DOF for 360° continuous rotation,so it can be applied as a flight simulator for a fighter?aircraft to achieve spin maneuvering. Because of the introduction of the hybrid structure and double parallel manipulator of themechanism,the redundancy exists with respect to both kinematics and actuation. Kinematics is carried out and Jaco?bian matrix is established by means of screw theory. The inverse kinematics is given out by the analytical method. 64 groups inverse solutions are showed in a table by permutation. Forward kinematics is solved by an e ectively numeri?cal method. The forward numerical method is realized based on the analytically inverse kinematics and Jacobian matrix. The numerical examples show that the forward numerical method can be used in real?time control. The rollingmotion is considered in forward kinematics and a numerical example is given out. The proposed flight simulator can spin and there are three rotational DOF with a hybrid structure so that the novel flight simulator can be used in the field of the fighter?aircraft for pilots to train.

关键词： Parallel manipulator Hybrid mechanisms Actuation redundancy Flight simulator Kinematics Screw theory Jacobian matrix

Hydrothermal preparation of Nb-doped NaTaO_(3) with enhanced photocatalytic activity for removal of organic dye

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Chinese Journal of Chemical Engineering 2022年第6期35卷 142-149页

作者： Hao zhou qi Yin State Key Laboratory of Clean Energy Utilization Zhejiang UniversityHangzhou 310027China

The construction of efficient photocatalysts has received much attention in wastewater *** this study,Nb-doped NaTaO_(3) was prepared with different doping ratio by a facile hydrothermal *** prepared catalysts were analyzed by X-ray diffraction,scanning electron microscopy,Brunauer-EmmettTeller(BET)theory,ultraviolet–visible diffuse reflectance *** the synthesized catalysts were employed to degrade a model pollutant,methylene blue(MB),under a 250 W mercury *** characterization tests confirm that Nb was successfully doped into the crystal structure of NaTaO_(3) and the modified NaNb_(x)Ta_(1)·xO_(3)(x is the doping ratio;x=0.25,0.5,0.75)samples were formed,which were in regular cubic shapes just like pure NaTaO_(3).The synthesized NaNb_(x)Ta_(1)·xO_(3)(x=0.25,0.5,0.75)had improved specific surface area and narrowed band gaps compared with pure NaTaO_(3).In photocatalytic degradation experiments,NaNb0.75Ta0.25O_(3) presented the best photocatalytic activity ascribed to the narrow band gap and the high surface area,degradating 95.7%of MB after 180 min of reaction,which was even twice the ability of pure NaTaO_(3).Besides,the effects of possible inorganic anions and cations in wastewater on photocatalytic degradation were *** spin resonance(ESR)tests and capture experiments were also conducted and a possible photocatalytic mechanism was *** work provides a direction for constructing superior NaTaO_(3)-based photocatalysts to be widely utilized in environmental protection.

关键词： Photocatalytic degradation Methylene blue NaTaO_(3)

A chromosome minimalist view of genome regulation and evolution based on mouse chromosome engineering

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Zoological Research 2022年第6期43卷 949-951页

作者： qi zhou MOE Laboratory of Biosystems Homeostasis and Protection and Zhejiang Provincial Key Laboratory for Cancer Molecular Cell Biology Life Sciences InstituteZhejiang UniversityHangzhouZhejiang 310058China Center for Reproductive Medicine 2nd Affiliated HospitalSchool of MedicineZhejiang UniversityHangzhouZhejiang 310052China Evolutionary&Organismal Biology Research Center School of MedicineZhejiang UniversityHangzhouZhejiang 310058China

What is the minimum number of chromosomes that a eukaryotic species can tolerate?This question has long fascinated biologists as chromosomal rearrangements are associated with both speciation and various genetic *** a... 详细信息

关键词： evolution Kunming chromosome

Characteristics of the Structure and Properties of ZnSnO3 Films by Varying the Magnetron Sputtering Parameters

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Acta Metallurgica Sinica(English Letters) 2016年第9期29卷 827-833页

作者： fa-Yu Wu Jian-Wei Li Yi qi Wu-Tong Ding Yuan-Yuan Guo Yan-Wen zhou Laser Advanced Manufacturing Technology Center School of Materials and Metallurgy University of Science and Technology Liaoning Anshan 114051 China SINOTRUK (Hong Kong) Limited Jinan Casting and Forging Center Zhangqiu 250200 China School of Material Science and Engineering Shenyang University of Technology Shenyang 110870 China

Transparent conductive oxide ZnSnO3 films were prepared by radio-frequency magnetron sputtering from powder targets and were characterized by X-ray photoelectron spectroscopy, X-ray diffraction, transmission electron microscopy, atomic force microscopy, surface profile, UV-Vis spectroscopy, and Hall effect. The structures of the films were either amorphous or nanocrystalline depending on sputtering parameters including deposition time, target power, chamber pressure, and the target-substrate separation. The average transmittance of the ZnSnO3 films within the visible wavelength was approximately 80% and the resistivity of the ZnSnO3 films was in the range of 10^-3-10^-4 Ω cm. The structural, optical, and electrical properties of the ZnSnO3 films could be adjusted and regulated by optimizing the sputtering process, allowing materials with specific properties to be designed.

关键词： ZnSnO3 film Powder target Magnetron sputtering Optical property Electrical property