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Numerical simulation of 3D-microstructures in solidification processes based on the CAFE method

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International Journal of Minerals,Metallurgy and Materials 2009年第6期16卷 640-645页

作者： Jin-long Wang Fu-ming Wang Yan-yu Zhao Jiong-ming zhang Wei Ren School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing 100083 China

It was analyzed that the finite element-cellular automaton （CAFE） method was used to simulate 3D-microstructures in solidification processes. Based on this method, the 3D-microstructure of 9SMn28 free-cutting steel was simulated in solidification processes and the simulation results are consistent with the experimental ones. In addition, the effects of Gaussian distribution parameters were also studied. The simulation results show that the higher the mean undercooling, the larger the columnar dendrite zones, and the larger the maximum nucleation density, the smaller the size of grains. The larger the standard deviation, the less the number of minimum grains is. However, the uniformity degree decreases first, and then increases gradually.

关键词： finite element-cellular automaton model numerical simulation solidification 3D-microstructure Gaussian distribution parameters

A Novel β-1,4-N, 6-O-Diacetylmuramidase from Streptomyces griseus and its Chemical Modification

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Chinese Chemical Letters 2006年第11期17卷 1469-1472页

作者： Chang Kui SUN yu Zhen zhang ming CHEN State Key Laboratory of Microbial Technology Shandong University Ji＇nan 250100

A novel lysozyme named β-1, 4-N, 6-O-diacetylmuramidase R2 was purified and characterized from Streptomyces griseus. The molecular weight of the enzyme was determined by MALDI-TOF-MS as 23.5 kDa. The N-terminal amino acid sequence was DTSGVQGIDVSHWQG. Chemical modification of β-1, 4-N, 6-O-diacetylmuramidase R2 indicated that sulfhydryl group and carbamidine of arginine residues are not essential for the activity of the enzyme, but lysine residues and imidazole of histidine residues are essential for the activity. The number of essential tryptophan and carboxyl groups was found that only one tryptophan residue and three carboxyl groups in the active site.

关键词： Chemical modification β-1 4-N 6-O-diacetylmuramidase lysozyme.

Comparative pyrolysis kinetics of heavy oil and its SARA fractions using distributed activation energy model

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Petroleum Science 2023年第5期20卷 3231-3239页

作者： Qing-An Xiong yu-ming zhang Pei Qiao Guo-Tong Li Jia-Zhou Li Wei zhang College of Mechanical and Transportation Engineering China University of PetroleumBeijing102249China

The pyrolysis behaviors of Qingdao vacuum residue(QD-VR)and its SARA(saturates,aromatics,reins,and asphaltenes)fractions were evaluated by thermo-gravimetric with mass spectrometer(TG-MS).The pyrolysis kinetics were determined by Friedman,one-parallel and four-parallel distributed activation energy model(DAEM),*** results indicated that the pyrolysis behavior of QD-VR was similar to that of *** saturates,the release of H_(2),CH_(4),CO,and CO_(2) occurred in 80-400℃,while the temperature range for QD-VR and other fractions is 200-800℃.The average activation energy(Ea)via Friedman method was 179.72 kJ/mol and increased with the conversion ***-parallel Gaussian DAEM was more suitable to describe the pyrolysis process of the single SARA fractions,while four-parallel Gaussian DAEM was more suitable to describe the pyrolysis process of heavy ***,comparing the weighted E_(a) from one-parallel(227.64 kJ/mol)and four-parallel Gaussian DAEM(204.63 kJ/mol),the results suggested that during pyrolysis process of heavy oil,there was an interaction between the SARA fractions,which could reduce the E_(a) of heavy oil ***,during heavy oil pyrolysis,resins and asphaltenes could increase the E_(a) of saturates and aromatics,while saturates and aromatics could decrease the E_(a) of resins and asphaltenes.

关键词： Heavy oil Pyrolysis kinetics SARA fractions DAEM

Thermal hydraulic and mechanical analysis of CH HCSB TBM

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核聚变与等离子体物理 2006年第3期26卷 181-185页

作者： WANG Xiao-yu FENG Kai-ming zhang Guo-shu yuAN Tao Southwestern Institute of Physics Chengdu 610041

Based on the structure design and results of neutronics analysis of the CH HCSB TBM (Chinese helium cooled solid breeder test blanket module), thermal hydraulic and mechanical analyses have been carried out. Results s... 详细信息

关键词：热水力分析中子物理学分析再生区热核反应

Micro-positron emission tomography imaging of angiogenesis based on ^(18)F-RGD for assessing liver metastasis of colorectal cancer

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Hepatobiliary & Pancreatic Diseases International 2021年第4期20卷 345-351页

作者： ming-yu zhang Hui-Jie Jiang Hao Jiang Rong-Jun zhang Zhen-Chang Wang Department of Nuclear Medicine Beijing Friendship HospitalCapital Medical UniversityBeijing 100050China Department of Radiology The Second Affiliated Hospital of Harbin Medical UniversityHarbin 150086China Jiangsu Institute of Nuclear Medicine Wuxi 214063China Department of Radiology Beijing Friendship HospitalCapital Medical UniversityBeijing 100050China

Background:Positron emission tomography (PET) imaging is a non-invasive method to visualize and quantify the tumor *** study aimed to explore the feasibility of ^(18)F-AIF-NOTA-E[PEG_(4-c)(RGDfk)]_(2) (denoted as ^(18)F-RGD) PET quantitative parameters to distinguish the angiogenesis in colorectal cancer (CRC) mice which has different metastatic ***:Twenty Lo Vo and twenty LS174T of CRC liver metastases animal models were established by implantation of human CRC cell lines via intrasplenic ***-based micro-PET imaging of animal model was performed and the uptake of ^(18)F-RGD tracer in the tumor tissues was quantified as tumor-to-liver maximum or mean standardized uptake value (SUVmax or SUVmean) *** correlation was used to analyze the relationship between radioactive parameters and tumor ***:The SUVmax and SUVmean ratios of Lo Vo model were significantly higher than those of LS174T in both liver metastasis and primary tumor lesions (P<0.05).A significant difference was observed in both vascular endothelial growth factor (VEGF) and Ki67 expressions between Lo Vo and LS174T primary tumors (P<0.05).The tumor-to-liver SUVmax or SUVmean ratio of ^(18)F-RGD showed a moderate correlation with VEGF expression (r=0.5700,P=0.001 and r=0.6657,P<0.001,respectively),but the SUVmean ration showed a weak correlation with Ki67 expression (r=0.3706,P<0.05).The areas under the receiver operating characteristic (ROC) curves of ^(18)F-RGD SUVmean ratio,SUVmax ratio for differentiating Lo Vo from LS174T tumor were 0.801 and 0.759,***:The tumor-to-liver SUVmean ratio of ^(18)F-RGD was a promising image parameter for the process of monitoring tumor angiogenesis in CRC xenograft mice model.

关键词： RGD peptide Positron emission tomography Colorectal liver metastases Vascular endothelial growth factor

Methods for Thickness Determination of SiC Homoepilayers by Using Infrared Reflectance Spectroscopy

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Chinese Physics Letters 2010年第6期27卷 240-243页

作者： LI Zhi-yun SUN Ji-Wei zhang yu-ming zhang Yi-Men TANG Xiao-Yan Key Laboratory of Wide Band-Gap Semiconductor Materials and Devices School of Microelectronics Xidian University Xi'an 710071

Infrared reflectance spectra have been widely used to measure layer thickness based either on calculation or on curve fitting, and two traditional methods for thickness determination have been studied. Considering the disadvantages of those two methods, we propose a new fitting model based on the fitting of the fringe order difference. In comparison with the measured results, the new fitting model shows its superiority not only for its stable and accurate results which have great agreement with the results from SEM, but also for its simple and quick fitting process.

关键词： THICKNESS measurement SILICON carbide INFRARED spectroscopy CURVE fitting COMPARATIVE studies SCANNING electron microscopy

Correlations of the expression of Cx43,SCFFBXW7,p-cyclin E1(Ser73),p-cyclin E1(Thr77)and p-cyclin E1(Thr395)in colon cancer tissues

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World Journal of Gastrointestinal Oncology 2025年第1期17卷 207-213页

作者： Rong-Gang Luan ming-Da Liu Zi-Feng Deng Cong-Lan Lu Mei-Ling yu ming-yu zhang Rong Liu Ran An You-Liang Yao Dong-Bei Guo Yong-Xing zhang Lei Zhao Department of Gastrointestinal Surgery Air Force Hospital of Eastern TheaterAnhui Medical UniversityNanjing 230032Jiangsu ProvinceChina State Key Laboratory of Molecular Vaccinology and Molecular Diagnostics School of Public HealthXiamen UniversityXiamen 361102Fujian ProvinceChina Trauma Surgery Air Force Hospital of Eastern TheaterAnhui Medical UniversityNanjing 230032Jiangsu ProvinceChina Department of Orthopaedics Air Force Hospital of Eastern TheaterAnhui Medical UniversityNanjing 230032Jiangsu ProvinceChina

BACKGROUND Previous cellular studies have demonstrated that elevated expression of Cx43 promotes the degradation of cyclin E1 and inhibits cell proliferation through ***,reduced expression results in a loss of this capacity to facilitate cyclin E *** ubiquitination and degradation of cyclin E1 may be associated with phosphorylation at specific sites on the protein,with Cx43 potentially enhancing this process by facilitating the phosphorylation of these critical *** To investigate the correlation between expression of Cx43,SKP1/Cullin1/F-box(SCF)FBXW7,p-cyclin E1(ser73,thr77,thr395)and clinicopathological indexes in colon *** Expression levels of Cx43,SCFFBXW7,p-cyclin E1(ser73,thr77,thr395)in 38 clinical colon cancer samples were detected by immunohistochemistry and were analyzed by statistical methods to discuss their *** Positive rate of Cx43,SCFFBXW7,p-cyclin E1(Ser73),p-cyclin E1(Thr77)and p-cyclin E1(Thr395)in detected samples were 76.32%,76.32%,65.79%,5.26%and 55.26%*** expressions of these proteins were not related to the tissue type,degree of tissue differentiation or lymph node ***43 and SCFFBXW7(r=0.749),p-cyclin E1(Ser73)(r=0.667)and p-cyclin E1(Thr395)(r=0.457),SCFFBXW7 and p-cyclin E1(Ser73)(r=0.703)and p-cyclin E1(Thr395)(0.415)were correlated in colon cancer(P<0.05),and expressions of the above proteins were positively correlated in colon *** Cx43 may facilitate the phosphorylation of cyclin E1 at the Ser73 and Thr195 sites through its interaction with SCFFBXW7,thereby influencing the ubiquitination and degradation of cyclin E1.

关键词： Colon cancer Cx43 SCFFBXW7 Phosphorylation of cyclin E1 Sites of cyclin E1 Correlation analysis

Ultrasonic Nebulization Extraction Coupled with Gas Chromatography-Mass Spectrometry for Analysis of Volatile Components in Traditional Chinese Patent Medicine

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Chemical Research in Chinese Universities 2011年第2期27卷 203-207页

作者： LIANG yue WANG Lu WANG Zi-ming yu Cui zhang Han-qi SHI yu-hua College of Chemistry Jilin University Changchun 130012 P. R. China

The ultrasonic nebulization extraction（UNE） was developed and applied to the extraction of volatile components from traditional Chinese patent medicine Xiaoyao Pills. Several parameters of ultrasonic nebulization extraction including the sample particle size, solvent volume, extraction time and ultrasonic power were studied and selected. As a result, 2.4 g of sample with particle size of 80 mesh was extracted with 15 mL of n-hexane for 20 min at an ultrasonic power of 35 W. The volatile components were analyzed by gas chromatography-mass spectrometry （GC-MS） under the optimal conditions and 57 compounds were identified. The precision, repeatability and stability of the proposed method were also studied. Compared with ultrasonic-assisted extraction（UAE） and hydrodistillation（HD） extraction, the proposed method is more efficient, faster and easier to be operated at room temperature with smaller sample and energy consumption. It is suggested that the ultrasonic nebulization extraction can be used as a novel alternative method for the extraction of volatile components from traditional Chinese patent medicine.

关键词： Ultrasonic nebulization extraction Gas chromatography-mass spectrometry Volatile component Traditional Chinese patent medicine

Simulation of SiC radiation detector degradation

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Chinese Physics B 2019年第1期28卷 300-305页

作者： Hai-Li Huang Xiao-Yan Tang Hui Guo Yi-Men zhang yu-Tian Wang yu-ming zhang School of Microelectronics Xidian University Key Laboratory of Wide Band-Gap Semiconductor Materials and Devices Xidian University

Simulation on the degradation of 4H-SiC Schottky detector was carried out using ISE TCAD, and the limit of the driftdiffusion analytical model was discussed. Two independent defect levels, rather than a pair of specific carrier lifetime, were induced to describe Z1/2 defects in simulation to calculate the charge collection efficiency versus bias voltage. Comparison between our calculation and the reported experimental results shows that an acceptable agreement was achieved, proving the feasibility of regarding Z1/2 defect as two individual defect levels. Such a treatment can simplify the simulation and may help to further investigate the detector degradation.

关键词： 4H-SiC detector degradation simulation Z1/2 defect