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Energy dissipation and contour integral characterizing fracture behavior of incremental plasticity

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Acta Mechanica Sinica 2011年第2期27卷 251-258页

作者： Qi-Lin He Lin-Zhi Wu ming Li hong-Bo chen chen Center for Composite Materials Harbin Institute of Technology 150080 Harbin China

J ep -integral is derived for characterizing the frac- ture behavior of elastic-plastic materials. The J ep -integral differs from Rice’s J-integral in that the free energy density rather than the stress working density is employed to define energy-momentum tensor. The J ep -integral is proved to be path-dependent regardless of incremental plasticity and deformation plasticity. The J epintegral possesses clearly clear physical meaning：（1） the value J ep tip evaluated on the infinitely small contour surrounding the crack tip represents the crack tip energy dissipation; （2） when the global steadystate crack growth condition is approached, the value of J ep farss calculated along the boundary contour equals to the sum of crack tip dissipation and bulk dissipation of plastic zone. The theoretical results are verified by simulating mode I crack problems.

关键词： J-integral · Energy dissipation · Proportional loading · Deformation plasticity · Incremental plasticity

Severe acute pancreatitis in the elderly: Etiology and clinical characteristics

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World Journal of Gastroenterology 2008年第16期14卷 2517-2521页

作者： ming-Jun Xin hong chen Bin Luo Jia-Bang Sun Department of General Surgery Xuanwu Hospital Capital Medical University Beijing 100053 China

AIM: To investigate the etiology and clinical characteristics of severe acute pancreatitis (SAP) in elderly patients (≥ 60 years of age). METHODS: We reviewed retrospectively all the SAP cases treated in Xuanwu Hospital in Beijing between 2000 and 2007. RESULTS: In 169 patients with SAP, 94 were elderly and 16 died. Biliary and idiopathic etiologies were the first two causes that accounted for over 90% of SAP in the elderly. Biliary, hyperlipemic and alcoholic etiologies were the first three causes in the young. The proportion of co- morbidity of cholelithiasis, biliary infection, hypertension and coronary heart disease in the aged was significantly higher than that in their young partners. The scores of APACHE Ⅱ and Ranson were also significantly higher in the elderly except the CT score. Organ failures were more common in the elderly, but the local pancreatic complications were not different between the two groups. Mortality of the aged was correlated with the severity of SAP, multiple co-morbidity and incidence of multiple organ dysfunction syndrome (MODS). MODS was the main cause of death. CONCLUSION: The etiology of SAP in the elderly is quite different from that in the young. Biliary and unknown factors are main causes in the aged. The elderly are subject to major organ failures but there is no difference in the occurrence of local pancreatic complications between the elderly and the young. It is crucial to monitor and improve the functions of major organs so as to prevent MODS in the aged with SAP.

关键词： Severe acute pancreatitis Elderly Etiology Mortality Complication

Effect of 2-(8-hydroxy-6-methoxy-1-oxo-1H-2-benzopyran-3-yl) propionic acid in combination with carboplatin on gastric carcinoma growth in vivo

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World Journal of Gastroenterology 2007年第4期13卷 509-514页

作者： Jin-Lian chen Jin-Shui Zhu Jing hong ming-Xiang chen Jin-Lai Lu Wei-Xiong chen Bo Shen Zu-ming Zhu Ni-Wei chen Department of Gastroenterology Shanghai Sixth People's Hospital Shanghai Jiaotong University Shanghai 200233 China

AIM： To investigate the effects of 2-（8-hydroxy-6- methoxy-l-oxo-lH-2-benzopyran-3-yl） propionic acid （NM-3） alone and in combination with carboplatin on tumor growth and apoptosis in mouse models of human gastric cancer constructed by subcutaneous implantation of histologically intact tumor tissue. METHODS： Human gastric cancer SGC-7901 tissues were implanted into the dorsal subcutis of nude mice. One week after tumors reached to a volume of 50-100 mm3 for around 1 wk, these mice were randomly divided into 8 groups （n = 10）. NM-3 was injected peritoneally at the dose of 10 mg/kg, 20 mg/kg or 40 mg/kg every other day for 5 wk, combined with carboplatin （5 mg/kg） every third day for 4 wk. As controls of combined treatment, another 4 groups of mice were injected with either NM-3 at 10 mg/kg, 20 mg/kg or 40 mg/kg, or with carboplatin alone （5 mg/kg）. The control mice received normal saline. Tumor weight, tumor growth inhibition （TGI）, and intratumoral microvessel density （MVD） were evaluated. Apoptosis of human gastric cancer was detected by TUNEL method and flow o/tometry analysis, respectively. RESULTS： The mean tumor volume （692.40 ± 58.43 mm3, 548.30 ± 66.02 mm3, 382.13 ± 43.52 mm3） after treatment with carboplatin combined NM-3 at the dose of 10 mg/kg, 20 mg/kg or 40 mg/kg was lower than that after treatment with either NM-3 at the dose of 10 mg/kg, 20 mg/kg or 40 mg/kg or with carboplatin alone. Compared with the normal saline group, NM-3 administered at 10 mg/kg, 20 mg/kg or 40 mg/kg significantly reduced the tumor weight in these groups （P 〈 0.05）. Carboplatin used alone at 5 mg/kg showed minimal effects. But NM-3 in combination with carboplatin had greater effects of tumor weight than either NM-3 or carboplatin alone. NM-3 alone at the dose 10 mg/kg or in combination with carboplatin had no obvious effects on body changes. Two mice died of diarrhea in each of the two groups treated with 40 mg/kg NM-3 or with 40 mg/kg NM-3 in combination with carboplatin. A

关键词： NM-3 Carboplatin Gastric carcinoma Angiogenesis Apoptosis

Expression of Bmi-1 and PAI-1 in esophageal squamous cell carcinoma

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World Journal of Gastroenterology 2014年第18期20卷 5533-5539页

作者： Yan Zhang Ya-Lou Zhang hong-ming chen hong-Wei Pu Wen-Jing Ma Xiao-Mei Li hong Ma Xiao chen College of Basic Medical Sciences Xinjiang Medical University Clinical Research Institute Xinjiang Medical University Vocational and Technical College Xinjiang Medical University Department of Pathology Xinjiang Medical University

AIM: To determine the correlation between invasiveness, migration and prognosis in esophageal squamous cell carcinoma (ESCC) and expression of the B-cell-specific Moloney leukemia virus insert site 1 (Bmi-1) and plasm... 详细信息

关键词： Esophageal squamous cell carcinoma B-cell-specific moloney leukemia virus insert site 1 Plasminogen activator inhibitor-1 Metastasis Prognosis

Adaptive PMD compensation experiment in 40 Gb/s CSRZ system

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Optoelectronics Letters 2007年第3期3卷 207-210页

作者： ZHANG Qi chen ming-hua chen hong-wei ZHANG Ji-yu Department of Electronic Engineering Tsinghua Univ. Beijing 100084 China

In 40 Gb/s systems with low polarization-mode dispersion(PMD) fibers,first-order PMD is the dominate factor with quite small value. An adaptive PMD compensator consisting of an electrical polarization controller(PC) ,a section of polariza-tion maintaining fiber(PMF) ,a degree of polarization(DOP) detector and a feedback control module is employed in 40 Gb/s NSFCNet. This compensator has a simple structure and high speed,which can compensate up to 20 ps first-order PMD adaptively and the average searching time is 2 ms.

关键词：自适应PMD补偿器补偿实验 CSRZ系统一阶PMD 光纤极化

Hydrothermal Synthesis and Characterization of Double Perovskites RSrMnFeO_6(R=La,Pr,Nd,Sm)

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Chemical Research in Chinese Universities 2010年第4期26卷 517-521页

作者： ZHANG Gang-hua YUAN hong-ming chen Yan LI Wei-juan YANG Mei-qi FENG Shou-hua State Key Laboratory of Inorganic Synthesis and Preparative Chemistry College of Chemistry Jilin University Changchun 130012 P. R. China

A series of double perovskites RSrMnFeO6（R=La, Pr, Nd, Sm） was synthesized under mild hydrothermal conditions. Crystal growths of the samples were sensitive to alkalinity, temperature, filling fraction, and composition of initial reaction mixture. The desired series of compounds belongs to the class of AA＇BB＇O6 perovskites with a random distribution of Mn and Fe atoms over the B-cation sub-lattice. Their structures show the distorted orthorhombic symmetry with space group Pnma. The shapes and sizes of the crystals were analyzed on a Rigaku JSM-6700F by scanning electron microscopy. Analysis done by XPS, Mossbauer spectroscopy and iodometric titration reveals that Mn and Fe ions have ＋4 and ＋3 oxidation states, respectively.

关键词： Double perovskites Orthorhombic Hydrothermal synthesis

Investigations on if-E Curve in Cyclic Derivative Chronopotentiometry (Ⅴ)——A Microcomputer-based Data Acquisition System for if-E Curve Measurements

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Chemical Research in Chinese Universities 1992年第2期8卷 158-159页

作者： SHEN Xue-ming , chen hong-yuan and GAO hong (Department of Chemistry, Nanjing University, Nanjing, 210008)

Introduction Quantitative analysis in cyclic derivative chronopotentiometry(CDC) is based on the measurement of the depth of incision on the (dE/dt)～E curve. A serious disadvantage of the method is that a large charging current obscures the measurement. To improve the sensitivity and the accuracy of CDC, a microcomputer-based data acquisi-

关键词： Cyclic derivative chronopotentiometry if-E curve Instrument

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PARM: a New QSAR Research Method Based on Genetic Algorithm

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Chinese Chemical Letters 1997年第11期8卷 975-978页

作者： hong ming chen Jia Ju ZHOU Tian Rui REN Gui Rong XIE (Laboratory of Computer Chemsitry, Institute of Chemical Metallurgy Chinses Academy of Sciences, Beijing 100080) Laboratory of Computer Chemsitry Institute of Chemical Metallurgy Chinese Academy of Sciences Beijing 100080 China

Based on Waiters' GERM([3])(Genetic Evolved Receptor Model) algorithm, an improved algorithm PARM(Pseudo Atomic Receptor Model) was put forward. FARM uses combination of genetic algorithm and cross-validation technique to produce atomic-level pseudo receptor model, based on a set of known structure-activity relationship. This algorithm has been applied to one system and afforded reasonable results. In recent years, there have appeared numerous computer programs([1,2]) which can build potential new ligands, based on three-dimensional structure of a receptor protein. Hower, in drug discovery, it is common to have measured activity data for a set of compounds acting upon a particular receptor protein but not to have knowledge of the three-dimensional structure of the protein active site. To solve this kind of problem, in present work, we put forward a FARM algorithm which was based on Waiters' GERM algorithm to predict bioactivity.

关键词： QSAR PARM

FOUR NEW SESQUITERPENES FROM LIGULARIA VIRGAUREA

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Chinese Chemical Letters 1991年第11期2卷 849-852页

作者： hong ming chen and Zhong Jian JIA~② Institute of Organic Chemistry, Lanzhou University, Lanzhou 730000

Four new sesquiterpenes were isolated from the roots of Ligularia virgaurea, and identified as furanomexicanane-9-ene-8-one(1), 9β, 10β-epoxyfuranomexicanane-8-one(2), virgauride(3) and virgaurin A(4) by spectral me... 详细信息

关键词： ppm DE FOUR NEW SESQUITERPENES FROM LIGULARIA VIRGAUREA