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Research progress in the inner surface modification of metal tubes by plasma processing

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Progress in Natural science:Materials International 2006年第11期16卷 1119-1126页

作者： ZHANG Guling~ 1,2.**, WU Xingfang~1, GU Weichao~2. chen Guangliang~2. FENG Wenran~2. NIU Erwu~2. LI Li~2. L Guohua~2. chen Huan~2. FAN Songhua~2. LIU Chizi~2.and YANG Size~2.1. School of Material {2. and Engineering, University of {2. and Technology beijing, beijing 100083, china 2. beijing National Laboratory for Condensed Matter Physics, Institute of Physics, Chinese Academy of {2.s, beijing 100080, china) School of Material science and Engineering University of Science and Technology Beijing Beijing 100083 China beijing National Laboratory for Condensed Matter Physics Institute of Physics Chinese Academy of Sciences Beijing 100080 China

The recent progress in inner surface hardening of tubes by plasma processing is summerized. Several techniques of inner surface plasma source ion implantation and deposition are introduced, and their advantages and disadvantages are discussed. The basic principles, technical features and new progress of inner surface plasma source ion implantation methods for metal tubes, which were developed in our laboratory, are described in detail. And perspectives of the future technical development for inner surface ion implantation of tubes are presented.

关键词： PSII metal tubes inner surface surface modification.

The numerical method for three-dimensional impact with friction of multi-rigid-body system

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science china(Physics,Mechanics & Astronomy) 2006年第1期49卷 102-118页

作者： ZHAO Zhen1,2. LIU Caishan2.& chen Bin2.1. beijing Institute of Graphic Communication, beijing 102.00, china 2. Department of Mechanics & Engineering science, Peking University, beijing 100871, china beijing Institute of Graphic Communication Beijing China Department of Mechanics & Engineering science Peking University Beijing China

The differential equations for planar impacts reduce to an algebraic form, and can be easily solved. For three dimensional impacts with friction, there is no closed-form solution, and numerical integration is required due to the swerve behavior of tangential impulse during collisions. The dynamic governing equations in the impact process are built up in impulse space based on the Lagrangian equation in this paper. The coefficient of restitution defined by Poisson is used as the condition of impact termination. A valid nu- merical method for solving three-dimensional frictional impact of multi-rigid body system is established. The singular cases of tangential movement in sticking point are especially noticed and analyzed. Several examples are present to reveal the different kinds of tan- gential movement modes varied with the normal impulse during collision.

关键词： multi-rigid body, impact, friction.

Association of physical activity with risk of chronic kidney disease in china:A population-based cohort study

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Journal of Sport and Health science 2024年第2期13卷 204-211页

作者： Kexiang Shi Yunqing Zhu Jun Lv Dianjianyi Sun Pei Pei Huaidong Du Yiping chen Ling Yang Bing Han Rebecca Stevens Junshi chen Zhengming chen Liming Li Canqing Yu china Kadoorie Biobank collaborative group Department of Epidemiology&Biostatistics School of Public HealthPeking University Health Science CenterBeijing 100191China Peking University Center for Public Health and Epidemic Preparedness&Response Beijing 100191China Key Laboratory of Epidemiology of Major Diseases(Peking University) Ministry of EducationBeijing 100191China Clinical Trial Service Unit&Epidemiological Studies Unit(CTSU) Nuffield Department of Population HealthUniversity of OxfordOxford OX37LFUK Medical Research Council Population Health Research Unit at the University of Oxford Oxford OX37LFUK NCDs Prevention and Control Department Henan Center for Disease Control and PreventionZhengzhou 450016China china National Center for Food Safety Risk Assessment Beijing 100022China 不详

Background:Information on the association between physical activity(PA)and the risk of chronic kidney disease(CKD)is *** aimed to explore the associations of total,domain-specific,and intensity-specific PA with CKD and its subtypes in ***:The study included 475,376 adults from the china Kadoorie Biobank aged 30-79 years during 2.04-2.08 at *** interviewer-administered questionnaire was used to collect the information about PA,which was quantified as metabolic equivalent of task hours per day(MET-h/day)and categorized into 4 groups based on *** regression was used to analyze the association between PA and CKD ***:During a median follow-up of 12.1 years,5415 incident CKD cases were documented,including 1159 incident diabetic kidney disease(DKD){2.es and 362.incident hypertensive nephropathy(HTN)*** PA was inversely associated with CKD risk,with an adjusted hazard ratio(HR,95%confidence interval(95%CI))of 0.83(0.75-0.92.for incident CKD in the highest quartile of total PA as compared with participants in the lowest *** results were observed for risk of DKD and HTN,and the corresponding HRs(95%CIs)were 0.75(0.58-0.97)for DKD risk and 0.56(0.37-0.85)for HTN *** nonoccupational PA,low-intensity PA,and moderate-to-vigorous-intensity PA were significantly associated with a decreased risk of CKD,with HRs(95%CIs)of 0.80(0.73-0.88),0.85(0.77-0.94),and 0.85(0.76-0.95)in the highest quartile,***:PA,including nonoccupational PA,low-intensity PA,and moderate-to-vigorous-intensity PA,was inversely associated with the risk of CKD,including DKD,HTN,and other CKD,and such associations were dose dependent.

关键词： Chronic kidney disease Domain Intensity Physical activity

A New Method for Fractal Dimension Determination by STM at Nanometer Scale

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International Journal of Minerals,Metallurgy and Materials 1999年第1期13卷 64-68页

作者： Qikai Li Yue Zhang Wuyang Chu chen Wang Chunli Bai (Applied science School. University of science and Technology beijing, beijing 100083. china)(Chemical Institute, Chinese Academy of science, beijing 100080. china) Applied science School University of Science and Technology Beijing Beijing 100083 China Chemical Institute Chinese Academy of Science Beijing 100080 China

A new method for determining the fractal dimension by STM at nanomeler scale has been ***- Mandelbrot fractal curves were used to verify the accuracy and reliability. The Computer simulation showed that fractal dimen- sion obtained with this method generally outran the traditional yard method. The new method has been applied to the fractal dimension determination of the fractures of Ti3Al and Ti-2.Al-11Nb alloys. The results show that the fractal dimension of Ti-2.Al-11Nb alloy is higher than that of Ti3Al, and it varies with the crark extending orientation.

关键词： fractal dimension STM nanometer scale Ti-Al alloy

Weight hierarchies of linear codes satisfying the Near-Chain condition

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Progress in Natural science:Materials International 2005年第9期15卷 784-792页

作者： LIU Zihui1** and chen Wende2.1. School of Mathematical sciences, Peking University, {2. 100871, china 2. Laboratory of Systems and Control and Key State Laboratory of Information Security, Institute of Systems science, Academy of Mathematics and Systems science, Chinese Academy of sciences, beijing 100080, china) School of Mathematical sciences Peking University Beijing 100871 China Laboratory of Systems and Control and Key State Laboratory of Information Security Institute of Systems Science Academy of Mathematics and Systems Sciences Chinese Academy of Sciences Beijing 100080 China

The weight hierarchies of a linear [n,k;q] code C satisfying the Near-Chain condition are studied, almost all the weight hierarchies of such code are determined.

关键词： weight hierarchy Near-Chain condition difference sequence linear code.

Chinese expert consensus on refined diagnosis,treatment,and management of advanced primary liver cancer(2.2. edition)

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Structure and kinematic analysis of a novel 2.DOF translational parallel robot

肝脏研究（英文） 2024年第2期8卷 61-71页

作者： Xiufeng Liu Feng Xia Yue chen Huichuan Sun Zhengqiang Yang Bo chen Ming Zhao Xinyu Bi Tao Peng Aizier Ainiwaer Zhiwen Luo Fusheng Wang Yinying Lu National Clinical Research Center for Infectious Diseases Society of Hepatology,{2. Medical Association Translational Medicine Branch,china Association of Gerontology and Geriatrics Department of Medical Oncology Bayi Hospital Affiliated to Nanjing Chinese Medical University NanjingJiangsuChina Department of Hepatobiliary Surgery Southwest HospitalArmy Medical University ChongqingChina Senior Department of Hepatology The Fifth Medical Center of PLA General HospitalBeijingChina Department of Liver Surgery and Transplantation Liver Cancer InstituteZhongshan HospitalFudan UniversityShanghaiChina Department of Interventional Therapy National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Department of Radiation Oncology National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Department of Minimally Invasive Interventional Therapy Liver Cancer Study and Service GroupSun Yat-sen University Cancer CenterGuangzhouGuangdongChina Department of Hepatobiliary Surgery National Cancer Center/National Clinical Research Center for Cancer/Cancer HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijingChina Department of Hepatobiliary Surgery The First Affiliated Hospital of Guangxi Medical UniversityNanningGuangxiChina Senior Department of Infectious Diseases The Fifth Medical Center of PLA General HospitalBeijingChina Comprehensive Liver Cancer Center The Fifth Medical Center of PLA General HospitalBeijingChina

Hepatocellular carcinoma(HCC),commonly known as primary liver cancer,is a major cause of malignant tumors and cancer-related deaths in china,accounting for approximately 85％of all cancer cases in the *** guidelines have been used to diagnose and treat liver ***,these guidelines provide a broad definition for classifying advanced liver cancer,with an emphasis on a singular approach,without considering treatment options for individual ***,it is necessary to establish a comprehensive and practical expert consensus,specifically for china,to enhance the diagnosis and treatment of HCC using the Delphi *** classification criteria were refined for Chinese patients with HCC,and the corresponding optimal treatment regimen recommendations were *** recommendations took into account various factors,including tumor characteristics,vascular tumor thrombus grade,distant metastasis,liver function status,portal hypertension,and the hepatitis B virus replication status of patients with primary HCC,along with treatment *** findings and rec-ommendations provide detailed,scientific,and reasonable individualized diagnosis and treatment strategies for clinicians.

关键词： Hepatocellular carcinoma (HCC) Targeted therapy Immunotherapy Refined diagnosis and treatment Expert consensus

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Progress in Natural science:Materials International 2007年第10期17卷 1213-1219页

作者： chen Tao1, Wu Chao2.and Liu Xinjun2.1. School of Application science and Technology, Harbin University of science and Technology, Harbin 150080, china 2. Department of Precision Instruments, Tsinghua University, beijing 100084, china) School of Application science and Technology Harbin University of Science and Technology Harbin 150080 China Department of Precision Instruments Tsinghua University Beijing 100084 China

This paper addresses the analysis of a novel parallel robot with 2.translational degrees of freedom (DOFs). The robot can position a rigid body in a plane with constant orientation. The kinematic structure of the robot is first described in detail. Some kinematic problems, such as the inverse and forward kinematics, velocity, and singularity are then analyzed. The working and assembly modes are discussed. Since it is the most important index to design a robot, the workspace of the robot is studied systematically in this paper. Based on the analysis of reachable workspace and singularity, a kind of workspace concept characterizing the region that the end-effector of the robot can reach in practice is defined. The results of this paper will be very useful for the design and application of the robot.

关键词： parallel robot degree of freedom kinematics workspace.

Fractal Structure of the Core Loss Spectrum of Co-based Amorphous Soft Magnetic Alloy with Constant Permeability

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International Journal of Minerals,Metallurgy and Materials 1999年第1期13卷 54-56页

作者： Yiping chen (Applied science School, University of science and Technology beijing, beijing 100083, china) Applied science School University of Science and Technology Beijing Beijing 100083 China

In order to check the traditional core loss formula, the core loss spectrum P(f) of Co-based amorphous soft magnetic alloy with constant permeability has been studied. It is found that within a high frequency range from 10 kHz to 2.0 kHz and at Bm = 0. 1 T,the P(f) has the fractal structure P (f) = Po, and with the increasing of induced anisotropy energy Ku, the fractal dimension Dfrises, thus the total power loss at high frequency increases and the frequency characteristic of P(f) becomes worse.

关键词： amorphous soft magnetic alloy constant permeability core loss fractal

In situ reproductive organs of Early Cretaceous ferns from Northeast china

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Chinese science Bulletin 1997年第23期42卷 1977-1980,2026页

作者： DENG Shenghui and chen Fen1. Research Institute of Petroleum and Development, beijing 100083 2.{2. University of Geosciences, beijing 100083,{2. Research Institute of Petroleum and Development Beijing china University of Geosciences Beijing China

FILICOPSIDA is a predominant group of the Early Cretaceous floras of Northeast china, whichapproximates 100 species and accounts for more than one third of the floras. The majority ofthis group are of great importance and significance in stratigraphy. The previous studies ofthese ferns are mainly morphological, with only a few concerning the in situ spores andsporangia. In recent years. the authors have carried out a research project on the in situreproductive organs of the Early Cretaceous ferns from/ basins of Inner Mongolia, Liaoning,Jilin and Heilongjiang of Northeast china. The study focuses on 35 species of 17 genera be-longing to 10 families. The present note briefly introduces the results of this study by listingsome representative species.

关键词： Northeast china Early Cretaceous Filicopsida in situ reproductive organs.