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Chinese Journal of Chemical Engineering 2021年第3期34卷 198-205页

作者： Nanhua wu Xiaohua Lu Rong An Xiaoyan ji Division of Energy Science/Energy Engineering LuleåUniversity of Technology97187 LuleåSweden State Key Laboratory of Materials-Oriented and Chemical Engineering Nanjing Tech UniversityNanjing 211816China Key Laboratory of Advanced Catalytic Materials and Technology School of Petrochemical EngineeringChangzhou UniversityChangzhou 213164China Herbert Gleiter Institute of Nanoscience Nanjing University of Science&TechnologyNanjing 210094China

Abnormal melting point depression of metal nanoparticles often occurs in heterogeneous catalytic reactions,which leads to a reduction in the stability of reactive *** study this abnormal phenomenon,the original and surface-energy modified Gibbs-Thomson equations were analyzed in this work and further modified by considering the effect of the *** results revealed that the original Gibbs-Thomson equation was not suitable for the particles with radii smaller than 10 ***,the performance of the surface-energy modified Gibbs-Thomson equation was improved,and the deviation was reduced to(-350-100)K,although further modification of the equation by considering the interfacial effect was necessary for the small particles(r<5 nm).The new model with the interfacial effect improved the model performance with a deviation of approximately-50 to 20 K,where the interfacial effect can be predicted quantitatively from the thermodynamic properties of the metal and ***,the micro-wetting parameterα_W can be used to qualitatively study the overall impact of the substrate on the melting point depression.

关键词： Melting point depression Metal nanoparticle Gibbs–Thomson equation Substrate Interfacial effect

A Fully Actuated System Approach for Stabilization of Discrete-Time Multiple-Input Nonlinear Systems with Distinct Input Delays

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Journal of Systems Science & Complexity 2022年第2期35卷 670-687页

作者： wu Ai-Guo ZHANG jie ji Youzhou Harbin Institute of Technology(Shenzhen) Shenzhen 518055China HIT wuhu Robot Technology Research Institute Wuhu 241008China

In this paper,the problem of stabilization is considered for discrete-time multiple-input nonlinear systems with distinct input delays law based on the fully actuated system *** order to compensate the input delays,a prediction scheme is presented to predict future states based on the closed-loop linear ***,a stabilizing law is constructed for nonlinear delayed systems by replacing the future states in the control law for the corresponding delay-free systems with their ***,numerical examples are given to verify the effectiveness of the proposed approach.

关键词： Fully actuated system approach input delays nonlinear systems prediction scheme

糖尿病与冠状动脉造影病变程度及特征的相关性分析

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中国医药 2009年第10期4卷 753-754页

作者：伦增瑞王健徐海年张俊刚赵春华季祥武山东省潍坊市人民医院心内一科 261041

目的探讨糖尿病与冠状动脉造影病变程度及其特征的关系。方法453例住院患者作为研究对象，所有患者均经选择性冠状动脉造影，根据造影结果对资料进行分组比较。结果合并糖尿病患者更多见前降支病变和多支病变；冠心病患者右冠状动脉和... 详细信息

目的探讨糖尿病与冠状动脉造影病变程度及其特征的关系。方法453例住院患者作为研究对象，所有患者均经选择性冠状动脉造影，根据造影结果对资料进行分组比较。结果合并糖尿病患者更多见前降支病变和多支病变；冠心病患者右冠状动脉和前降支病变较多见。随着糖尿病患病时间的延长，冠状动脉的病变程度逐渐加重，相关系数=0．356，P=0．001。糖尿病患者患病时间与Gensini评分呈正相关关系，相关系数=0．245，P=0．026。结论随着糖尿病患病时间的延长，Gensini评分基本呈逐渐增加的关系。这说明糖尿病是冠状动脉病变严重程度的相关因素。糖尿病是冠状动脉病变严重程度的相关因素，糖尿病患者病程愈长冠状动脉造影病变程度及范围愈重。

关键词：冠状动脉粥样硬化性心脏病糖尿病冠状动脉造影

Effect of Pd doping on the acetone-sensing properties of NdFeO_3

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International Journal of Minerals,Metallurgy and Materials 2012年第2期19卷 141-145页

作者： Zhan-lei wu Ru Zhang Ma Zhao Shao-ming Fang Zhou-xiang Han ji-fan Hu Kai-ying Wang Henan Provincial Key Laboratory of Surface ＆ Interface Zhengzhou University of Light hduslry Zhengzhou 450002 China School of Physics Shandong University Jinan 250100 China Institute for Mierosystem Technology Vestfold University College Horten 3184 Norway

The acetone-sensing properties of the undoped and Pd doped perovskite-type oxides NdFeO3 were investigated from room temperature to 400°C. The perovskite-type NdFeO3 was synthesized by a sol-gel method, and the dopants Pd with the content from 1wt% to 5wt% were implanted into NdFeO3 nanoparticles by thermal diffusion. X-ray diffraction （XRD） and scanning electron microscopy （SEM） techniques show that NdFeO3 is an orthorhombic structure with the average particle size of about 40 nm. A giant acetone-sensing response of 675.7 is observed when the Pd content in NdFeO3 powders is about 3wt%. The response and recovery time of the sensor to the 5×10–4 acetone gas are 16 and 1 s, respectively. At the same time, it performs a good selectivity to acetone gas and may be a new promising material candidate for the acetone-sensor development.

关键词： neodymium compounds nanostructures palladium doping acetone sensors sol-gel process

Numerical simulation of humping phenomenon in high speed gas metal arc welding

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Frontiers of Materials Science 2011年第2期5卷 90-97页

作者： ji CHEN Chuan-Song wu State Key Lab of Advanced Welding Production Technology Harbin Institute of Technology Harbin 150001 China Institute of Materials Joining Shandong University Jinan 250061 China

It is of great significance to obtain a thorough understanding of the physical mechanisms responsible for humping bead phenomenon in high speed gas metal arc welding （GMAW） in order to raise welding efficiency. Experiments were conducted to observe the weld pool behaviors in high speed GMAW, and it was found that both the severely deformed weld pool surface and strong backward flowing play a dominant role in humping bead formation. In this study, a mathematical model is developed to quantitatively analyze the forming mechanism of humping beads for high speed GMAW through considering both the momentum and heat content distribution of the backward flowing molten metal inside the weld pool. The transient development of temperature profiles in the weld pool with severe deformation demonstrates the humping bead forming process under some welding conditions. The predicted and measured humping bead dimensions are in agreement.

关键词： numerical simulation humping weld bead high-speed GMAW

Weak Solutions to the Cahn–Hilliard Equation with Degenerate Diffusion Mobility in R^N

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Acta Mathematica Sinica,English Series 2019年第10期35卷 1629-1654页

作者： ji Hui wu Lei LU College of Mathematics Physics and StatisticsShanghai University of Engineering ScienceShanghai 201620P.R.China College of Sciences Shanghai UniversityShanghai 200444P.R.China College of Mechanical Engineering Beijing University of TechnologyBeijing 100124P.R.China

This paper is concerned with a popular form of Cahn-Hilliard equation which plays an important role in understanding the evolution of phase separation. We get the existence and regularity of a weak solution to nonlinear parabolic, fourth order Cahn-Hilliard equation with degenerate mobility M(u)= u^m(1-u)^m which is allowed to vanish at 0 and 1. The existence and regularity of weak solutions to the degenerate Cahn-Hilliard equation are obtained by getting the limits of Cahn-Hilliard equation with non-degenerate mobility. We explore the initial value problem with compact support and obtain the local non-negative result. Further, the above derivation process is also suitable for the viscous Cahn–Hilliard equation with degenerate mobility.

关键词： Degenerate non-degenerate viscous convergence

Long-Term Outcome of A Large Series of Gastric Cancer Patients in China

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Chinese Journal of Cancer Research 2010年第3期22卷 167-175页

作者： Ai-wen wu jia-fu ji Hong Yang Yan-ning Li Shuang-xi Li Lian-hai Zhang Zi-yu Li Xiao-jiang wu xiang-long Zong Zhao-de Bu ji Zhang xiang-qian Su Yi Wang Guang-wei Xu Key Laboratory of Carcinogenesis and Translational Research （Ministry of Education） Department ofGastrointestinal Surgery Peking University School of Oncology Beijing Cancer Hospital ＆ Institute Beijing100142 China

Objective：The outcome of gastric cancer treatment in China is relatively poor compared with those in Japan and *** factors are not quite clear till *** aim of this study is to present data on gastric cancer patients from a single high volume cancer center of China and to illuminate relevant factors regarding unsatisfactory ***：A total of 2312 consecutive pathologically proven gastric carcinoma patients were treated in Beijing Cancer Hospital from January 1995 to December *** information including demographic information,tumor characteristics,therapeutic experience and survival was retrieved from the Database specially designed for Gastric Cancer Collaborative Group,Beijing Cancer ***：There were 1633 males and 679 females with a median age of 58.8 years（range 19-89）.Merely 181 patients were in the early stage（7.8%）.Curative resection was performed in less than 72% of the *** number of lymph nodes harvested varied from 0 to 71（average 9） while the median number of positive lymph node was 2（0-37）.Only in 650 patients the number of lymph nodes harvested was more than *** the end of follow-up,874 patients were still alive while 1132 *** 1,2,5,10-year overall survival were 68.50%,51.88%,36.83%,and 30.49%,*** analysis demonstrated that TNM stage,tumor location,tumor size,surgery,and vascular invasion were independent prognostic ***：The outcome of gastric cancer in China is not as good as *** detection and standardized curative resection should be prompted at present to improve the outcome.

关键词： Gastric cancer Management Outcome

The Maximum Principle for One Kind of Stochastic Optimization Problem and Application in Dynamic Measure of Risk

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Acta Mathematica Sinica,English Series 2007年第12期23卷 2189-2204页

作者： Shao Lin ji Zhen wu School of Mathematics and Systems Science Shandong University Jinan 250100 P. R. China

The authors get a maximum principle for one kind of stochastic optimization problem motivated by dynamic measure of risk. The dynamic measure of risk to an investor in a financial market can be studied in our framewor... 详细信息

关键词： backward stochastic differential equation perturbation method Ekeland's variational principle dynamic measure of risk

Theoretical Calculations of Optical Spectra and Their Pressure-Induced Shifts of MgAl_2O_4:Cr^(3+)

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Communications in Theoretical Physics 2008年第5期49卷 1339-1344页

作者： wu Fei ZHANG ji-Ping College of Physical Science and Technology Sichuan University Chengdu 610065 China

The energy levels of spectrum, wavefunetions and crystal-field parameters of MgAl2O4：Cr^3＋ at normal pressure have been calculated by the means of diagonalizing the complete d^3 energy matrix （DCEM）. With these results, the g factor of the ground state at normal pressure and the pressure-induced shift （PS） of the spectra1 levels are also calculated uniformly, and the calculated results are all in good agreement with the experimental ones. And the contributions of various crystal-field parameters to the energy levels at normal pressure and the variational rates of the R1 line shifting with the pressure are calculated, from which the physical origin of the red shift of the R1 line shifting with increasing pressure have been clearly shown.

关键词： crystal fields energy spectrum g factor high-pressure effect

Effect of the C.–1388 A>G polymorphism in chicken heat shock transcription factor 3 gene on heat tolerance

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Journal of Integrative Agriculture 2015年第9期14卷 1808-1815页

作者： ZHANG Wen-wu KONG Li-na ZHANG De-xiang ji Cong-liang ZHANG Xi-quan LUO Qing-bin College of Animal Science South China Agricultural University Key Laboary of Chicken Genetics Breeding and ReproductionMinistry of Agriculture/South China Agricultural University Guangdong Enterprise Laboary of Healthy Animal Husbandry and Environment Control South China Agricultural University Guangdong Wens Food Group Limited Company

Heat stress is one of the main factors that inlfuence poultry production. Heat shock proteins (HSPs) are known to affect heat tolerance. The formation of HSPs is regulated by heat shock transcription factor 3 (HSF3) in chicken. A DNA pool was established for identifying single nucleotide polymorphisms (SNPs) of the chicken HSF3, and 13 SNPs were detected. The bioinformatic analysis showed that 8 SNPs had the capacity to alter the transcription activity of HSF3. The dual luciferase report gene assay showed that there was a signiifcant difference (PG (S1) and C.–1 388 A>G (S4) sites at the 5′-untranslated region (UTR) of chicken HSF3. The elec-trophoretic mobility shift assay showed that the S4 site was a transcription binding factor. The analysis of the association of the S1 and S4 sites with heat tolerance index revealed that the S4 site was signiifcantly correlated with the CD3+T cel , corticosterone, and T3 levels in Lingshan chickens and with the heterophil/lymphocyte value in White Recessive Rock. These results showed that the S4 site at the 5′ UTR of chicken HSF3 might have an impact on heat tolerance in summer and could be used as a potential marker for the selection of chicken with heat tolerance in the future.

关键词： chicken heat shock factor 3 dual luciferase report gene heat tolerance