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Nuclear Science and Techniques 2022年第12期33卷 1-11页

作者： Chang‑Jun Li Xing‑Fu Cai ming‑qing xiao Yong‑Gang Huo Peng Xu Su‑Fen Li xiao‑Yan Cao Xi’an Research Institute of High-Tech Xi’an 710025China Air Force Engineering University Xi’an 710051China

Radioactive tritium leakage from high-pressure storage vessels is a common nuclear leakage *** leakage conditions have different effects on tritium diffusion,resulting in different degrees of radioactive *** study focuses on tritium leakage from high-pressure storage vessels and analyzes the influence of different leakage orifice shapes,leakage positions,and the presence of obstacles in the scene space on tritium leakage *** results show that there is little difference in the radial diffusion velocity of tritium gas along the jet axis between circular and square leakage *** radial diffusion velocity of tritium gas in the long-axis direction of the rectangular leakage orifice is larger than that in the short-axis direction,and the larger the aspect ratio of the rectangle is,the greater the difference is in the diffusion *** addition,leakage from the storage vessel below the air inlet is beneficial to the dilution of tritium,whereas leakage from the air vents leads to a slow decrease in the tritium *** obstacles present in the tritium scene space hinder the migration of tritium gas and prolong the time for the tritium concentration to reach *** study provides a theoretical basis for the disposal of tritium in tritium leakage accidents by analyzing the influence of different leakage conditions in storage vessels on tritium gas diffusion.

关键词： Tritium leakage Leakage orifice shape Leakage position Obstacles

Quantum Topological Studies on the Molecular Complexes-CO_2-NCH and CO_2-OH_2

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Chemical Research in Chinese Universities 1993年第1期9卷 65-69页

作者： LI qing-ming and FU xiao-yuan (Department of Chemistry, Beijing Normal University, Beijing, 100875)ZHANG Jing-chang and CAO Wei-liang (Beijing Institute of Chemical Technology, Beijing, 100031)

Topological properties of charge distribution for the title complexes and their constituent are analyzed by using ab initio calculations at 3-21G basis set. The results obtained are compared with those originated from ab initio and energy decomposition method. It has been determined that the title molecular complexes are T-shaped. The characteristics of the bonds and the changes originated from the formation of the complexes are discussed.

关键词： Charge density Molecular complex ab initio calculation

Theoretical studies on the substitution effect of fluorine on ethylene

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Chinese Journal of Chemistry 1993年第3期11卷 217-224页

作者： LI,qing-ming FU,xiao-Yuan Beijing Normal University,Beijing 100875ZHANG,Jing-Chang CAO,Wei-Liang Beijing Institute of Chemical Technology,Beijing 100031 Beijing Normal University Beijing 100875 Beijing Institute of Chemical Technology Beijing 100031

The substitution effect of fluorine on ethylene is investigated by means of studying the properties of the charge distribution at the bond critical points with the theory of atoms in *** is found that fluorine atom acts not only as a σ electron acceptor,but also as a π electron donor,and these double effects are reflected in the quantity of ellipticity,Lap- lacian and the charge density of charge distribution at the bond critical *** C—C,C—F bonds,the major axis of elliptical contours is perpendicular to the molecular plane,but for C—H bond,it is parallel to the molecular *** effects originating from the substi- tution have also been discussed.

关键词： Theoretical studies on the substitution effect of fluorine on ethylene

Finite-sensor fault-diagnosis simulation study of gas turbine engine using information entropy and deep belief networks

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Frontiers of Information Technology & Electronic Engineering 2016年第12期17卷 1287-1304页

作者： De-long FENG ming-qing xiao Ying-xi LIU Hai-fang SONG Zhao YANG Ze-wen HU Aeronautics and Astronautics Engineering College Air Force Engineering University Xi'an 710038 China Air Force Xi'an Flight Academy Xi'an 710306 China

Precise fault diagnosis is an important part of prognostics and health management. It can avoid accidents, extend the service life of the machine, and also reduce maintenance costs. For gas turbine engine fault diagnosis, we cannot install too many sensors in the engine because the operating environment of the engine is harsh and the sensors will not work in high temperature, at high rotation speed, or under high pressure. Thus, there is not enough sensory data from the working engine to diagnose potential failures using existing approaches. In this paper, we consider the problem of engine fault diagnosis using finite sensory data under complicated circumstances, and propose deep belief networks based on information entropy, IE-DBNs, for engine fault diagnosis. We first introduce several information entropies and propose joint complexity entropy based on single signal entropy. Second, the deep belief networks （DBNs） is analyzed and a logistic regression layer is added to the output of the DBNs. Then, information entropy is used in fault diagnosis and as the input for the DBNs. Comparison between the proposed IE-DBNs method and state-of-the-art machine learning approaches shows that the IE-DBNs method achieves higher accuracy.

关键词： Deep belief networks (DBNs) Fault diagnosis Information entropy Engine

Development of a micro-monitoring system based on the liquid crystal display

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Chinese Journal of Biomedical Engineering(English Edition) 2002年第3期11卷 133-139页

作者： DU xiao-lan,WU Bao-ming,HE qing-hua, xiao Jian, LIU Yan

objective: To introduce the development of a portable multi-parameter monitoring system. Methods: Using signal detecting and data processing techniques, this monitor with a graphic liquid crystal display (LCD) and a single-chip microprocessor 8Xc196Kc can dynamically measure electrocardiogram(ECG), breath wave, blood pressure (BP), breath frequency (BF), heart rate (HR) and body temperature (BT) in real-time. Results: This monitor can dynamically display the ECG, breath wave and other parameters in real time. It can also provide a 24h trend graph for each measured parameter and exchange data, through the serial communication interface (RS232), with the PC or hand-held PC (HPC). Conclusions: This portable monitoring system has a man-machine interface friendly. It is capable of performing continuous monitoring and also used as terminal of a central monitoring system or a tele-monitoring system.

关键词： monitor single-chip microcomputer LCD

THEORETICAL STUDIES ON THE SUBSTITUTION EFFECT OF FLUORINE ON ETHANE

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Chinese Journal of Structural Chemistry 1993年第4期 258-266页

作者： Li qing-ming Fu xiao-YuanChemistry Department,Beijing Normal University,Beijing 100875Zhang Jing-Chang Cao Wei-LiangApplied Chemistry Department,Beijing Institute of Chemical Technology,Beijing 100031

The substitution effect of fluorine on ethane has been investigated by means of studying the properties of the charge distribution at the bond critical points with the theory of atoms in *** is found that the major substitution effects of fluorine atom are positive a inductive and polarity *** the same time,fluorine atom partially provides π electrons to other chemical bonds by means of hy-perconjugation in molecules with two fluorine atoms and one or two carbon atoms in the same plane,and these effects are reflected in the quantity of bond ellipticity,Laplacian and the charge density of charge distribution at the bond critical *** substitution of hydrogen by fluorine in ethane strengthens all the bonds in substituted *** effects originating from the substitution of hydrogen by fluorine have also been discussed.

关键词： THEORETICAL STUDIES ON THE SUBSTITUTION EFFECT OF FLUORINE ON ETHANE

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淮山药淀粉糊化及质构特性

食品工业科技 2017年第6期38卷 110-115页

作者：赵小梅李清明苏小军舒青青廖卢艳肖潇韦本辉湖南农业大学食品科学与技术学院湖南长沙410128 作物种质创新与资源利用重点实验室湖南长沙410128 广西农业科学院经济作物研究所广西南宁530007

本实验选用新选育高淀粉含量淮山药提取淀粉,并采用快速粘度仪和质构仪研究了淀粉浓度、pH、蔗糖、卡拉胶、柠檬酸以及食盐对淮山药淀粉糊化以及质构特性的影响。实验结果表明增大淀粉浓度和蔗糖使淮山药淀粉的热稳定性变差,添加食盐能... 详细信息

本实验选用新选育高淀粉含量淮山药提取淀粉,并采用快速粘度仪和质构仪研究了淀粉浓度、pH、蔗糖、卡拉胶、柠檬酸以及食盐对淮山药淀粉糊化以及质构特性的影响。实验结果表明增大淀粉浓度和蔗糖使淮山药淀粉的热稳定性变差,添加食盐能增强其热稳定性;增加淀粉浓度、添加柠檬酸以及食盐可以增大淮山药淀粉的凝胶性,添加卡拉胶则相反;除pH外其他因素皆可增加淮山药淀粉的凝沉性;pH在弱酸及碱性条件下对淮山药淀粉的糊化及质构性质无太大影响;添加柠檬酸和食盐可减小淮山药淀粉凝胶的硬度、粘性和咀嚼性,增加淀粉浓度、添加蔗糖对其影响则相反。

关键词：淮山药淀粉糊化特性质构特性

中美贸易摩擦背景下中国商品出口地理方向的优化

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华南师范大学学报（社会科学版） 2019年第2期 93-98页

作者：蔡一鸣罗冰明小晴华南师范大学经济与管理学院

降低对美国市场的依赖是应对中美贸易摩擦的可行策略之一,而这意味着中国商品出口地理方向的调整。出口市场组合模型可以用于确定最优出口地理方向中每个市场的出口份额。根据该模型以及2008—2017年的中国出口贸易数据,可以得到如下政... 详细信息

降低对美国市场的依赖是应对中美贸易摩擦的可行策略之一,而这意味着中国商品出口地理方向的调整。出口市场组合模型可以用于确定最优出口地理方向中每个市场的出口份额。根据该模型以及2008—2017年的中国出口贸易数据,可以得到如下政策含义:在减少对美国市场过分依赖的同时,中国还要尽量减少对欧洲市场的出口份额,大幅度地增加对非洲、大洋洲和北美其他市场的出口份额,而亚洲和拉丁美洲在不同条件下也可以成为出口扩张的备选市场。

关键词：贸易摩擦中国出口出口地理方向优化

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中国文化产品对欧盟出口增长集约边际分析

佛山科学技术学院学报（社会科学版） 2022年第6期40卷 71-78页

作者：明小晴杨清广州华商学院经济贸易学院广东广州511399 华南师范大学经济管理学院广东广州510006

Hummels和Klenow的测算方法可用于测算中国与欧盟贸易伙伴国文化产品出口的集约边际值。利用扩展的贸易引力模型研究文化距离与文化产品出口增长集约边际的定量关系,实证分析结果显示文化距离对文化产品出口增长的集约边际有抑制作用。... 详细信息

Hummels和Klenow的测算方法可用于测算中国与欧盟贸易伙伴国文化产品出口的集约边际值。利用扩展的贸易引力模型研究文化距离与文化产品出口增长集约边际的定量关系,实证分析结果显示文化距离对文化产品出口增长的集约边际有抑制作用。集约边际减少表明企业出口产品数量的减少,这将不利于出口企业收入的稳定,不利于维持原有国际市场份额。要维持文化产品出口集约边际增长可从以下两方面入手:第一,加强文化交流,促进中国文化认同感;第二,政府企业协同合作,优化文化产品出口结构。

关键词：文化产品出口集约边际文化距离贸易引力模型

Robust Stability Analysis for T-S Fuzzy Singular Systems with Constraints

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Robust Stability Analysis for T-S Fuzzy Singular Systems wit...