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Analysis and optimization of performance parameters of the^(220)Rn chamber in flow-field mode using computational fluid dynamics method

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Nuclear Science and Techniques 2024年第10期35卷 70-85页

作者： shao-hua Hu Yong-Jun Ye Zheng-Zhong He De-Tao Xiao xiang-Yu Xu Jian-Kai Wang Qing-Zhi Zhou School of Nuclear Science and Technology University of South ChinaHengyang 421001China School of Resources Environment and Safety Engineering University of South ChinaHengyang 421001China

The impact of the radiation dose produced by^(222)Rn/^(220)Rn and its progeny on human health has garnered increasing interest in the nuclear research *** establishment of robust,regulatory,and competent^(220)Rn chambers is crucial for accurately measuring radioactivity ***,studying the uniformity of the^(220)Rn progeny through experimental methods is challenging,because measuring the concentration of^(220)Rn and its progeny in multiple spatial locations simultaneously and in real time using experimental methods is ***,achieving precise control of the concentration of^(220)Rn and its progeny as well as the reliable sampling of the progeny pose significant *** solve this problem,this study uses computational fluid dynamics to obtain the flow-field data of the^(220)Rn chamber under different wind speeds and progenyreplenishment *** analysis of the concentration distribution of the progeny and quantitative analysis of the progeny concentration and uniformity of the progeny concentration are *** research findings indicated that the progeny concentration level is primarily influenced by wind speed and the progeny-complement *** speed also plays a crucial role in determining progeny concentration uniformity,whereas the progeny-complement rate has minimal impact on *** ensure the accuracy of^(220)Rn progeny concentration sampling,we propose a methodology for selecting an appropriate sampling area based on varying progeny *** study holds immense importance for enhancing the regulation and measurement standards of^(220)Rn and its progeny.

关键词： Thoron Progeny Regulatory CFD simulation

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Cultural Exploration into Differences of Chinese and American Family Values

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学术界 2014年第12期 267-272页

作者： xiang hua School of Education Xi’an University

Chinese and American family values,marital views,educational mode,family ethics,and profit distributions have their own special characteristics. In this paper,the differences in values are discussed from the cultural dimension so as to provide a reference to form a core concept for the values difference,correctly treat and judge Sino- American family values and seek a developmental tendency for family values in the cultural conflict.

关键词： China the United States family values differences

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Investigation of multilevel ion-pairing effect of triferrocenylmethane in organic phase

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Chinese Chemical Letters 2014年第10期25卷 1379-1381页

作者： De-Bo xiang Hui-Bo shao Key Laboratory of Cluster Science(Ministry of Education of China) School of ChemistryBeijing Institute of Technology China Aviation Lithium Battery Co. Ltd.

The intramolecular electronic communication and multilevel ion-pairing effect of triferrocenylmethane（TriFcM） in organic phase was studied with the ＂thin-layer electrochemistry＂ *** pairs of symmetric peaks in cyclic voltammetry of TriFcM correspond to three one-electron electrochemical reaction processes and indicate strong intramolecular electronic communication,which could be used to study the multilevel ion-pairing *** different formation constants of ion-pairs between the three ferroceniums of TriFcM and perchlorate in thin organic film were obtained and compared.

关键词： Triferrocenylmethane Thin-layer electrochemistry Intramolecular electronic communication Multilevel ion-pairing effect

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Soil Organic Carbon, Black Carbon, and Enzyme Activity Under Long-Term Fertilization

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Journal of Integrative Agriculture 2014年第3期13卷 517-524页

作者： shao Xing-hua ZHENG Jian-wei Department of Life Science Shangrao Normal University

The present study aims to understand the effects of long-term fertilization on soil organic carbon （SOC）, black carbon （BC）, enzyme activity, and the relationships among these parameters. Paddy field was continuously fertilized over 30 yr with nine different fertilizer treatments including N, P, K, NP, NK, NPK, 2NPK （two-fold NPK）, NPK＋manure （NPKM）, and CK （no fertilization）, N, 90 kg urea-N ha^-1 yr^-1; P, 45 kg triple superphosphate-P205 ha^-1 yr^-1; K, 75 kg potassium chloride-K20 ha^-1 yr^-1; and pig manure, 22 500 kg ha^-1 yr^-1. Soil samples were collected and determined for SOC, BC content, and enzyme activity. The results showed that the SOC in the NPKM treatment was significantly higher than those in the K, P, and CK treatments. The lowest SOC content was found in the CK treatment. SOC content was similar in the N, NP, NK, NPK, 2NPK, and NPKM treatments. There was no significant difference in BC content among different treatments. The BC-to-SOC ratios （BC/SOC） ranged from 0.50 to 0.63, suggesting that BC might originate from the same source. Regarding enzyme activity, NPK treatment had higher urease activity than NPKM treatment. The urease activity of NPKM treatment was significantly higher than that of 2NPK, NP, N, P, K, CK, and NPKM treatment which produced higher activities of acid phosphatase, catalase, and invertase than all other treatments. Our results indicated that long-term fertilization did not significantly affect BC content. Concurrent application of manure and mineral fertilizers increased SOC content and significantly enhanced soil enzyme activities. Correlation analysis showed that catalase activity was significantly associated with invertase activity, but SOC, BC, and enzyme activity levels were not significantly correlated with one another. No significant correlations were observed between BC and soil enzymes. It is unknown whether soil enzymes play a role in the decomposition of BC.

关键词： organic carbon black carbon enzyme activity fertilization

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Conjugacy Classes and Characters for Extensions of Finite Groups

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Chinese Annals of Mathematics,Series B 2014年第5期35卷 743-750页

作者： xiang TANG Hsian-hua TSENG Department of Mathematics Washington University St.Louis MO 63130 USA Department of Mathematics Ohio State University 100 Math Tower231 West 18th Ave. ColumbusOH 43210 USA

Let H be an extension of a finite group Q by a finite group G. Inspired by the results of duality theorems for etale gerbes on orbifolds, the authors describe the number of conjugacy classes of H that map to the same conjugacy class of Q. Furthermore, a generalization of the orthogonality relation between characters of G is proved.

关键词： Group extensions Conjugacy classes Orthogonality of characters2000 MR Subject Classification 20E22 20C05

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Optimal Reinsurance and Investment Strategy with Delay in Heston’s SV Model

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Journal of the Operations Research Society of China 2021年第2期9卷 245-271页

作者： Chun-xiang A Ai-Lin Gu Yi shao School of Mathematics and Statistics Zhaoqing UniversityZhaoqing 526061GuangdongChina School of Applied Mathematics Guangdong University of TechnologyGuangzhou 510520China

In this paper,we consider an optimal investment and proportional reinsurance problem with delay,in which the insurer’s surplus process is described by a jump-diffusion *** insurer can buy proportional reinsurance to transfer part of the insurance claims *** addition to reinsurance,she also can invests her surplus in a financial market,which is consisted of a risk-free asset and a risky asset described by Heston’s stochastic volatility(SV)*** the performance-related capital flow,the insurer’s wealth process is modeled by a stochastic differential delay *** insurer’s target is to find the optimal investment and proportional reinsurance strategy to maximize the expected exponential utility of combined terminal *** explicitly derive the optimal strategy and the value ***,we provide some numerical examples to illustrate our results.

关键词： Proportional reinsurance Stochastic differential delay equation(SDDE) Heston’s stochastic volatility(SV)model Hamilton–Jacobi–Bellman(HJB)equation

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Dynamic Manipulability and Optimization of a Two DOF Parallel Mechanism

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Chinese Journal of Mechanical Engineering 2010年第4期23卷 403-409页

作者： shao hua WANG Jinsong WANG Liping GUAN Liwen Department of Precision Instrument and Mechanology Tsinghua University Beijing 100084 China

The dynamic dexterity is an important issue for manipulator design, some indices were proposed for analyzing dynamic dexterity, but they can evaluate the dynamic performance just at one pose in the workspaee of the manipulator, and can＇t be applied to dynamic design expediently. Much work has been done in the kinematic optimization, but the work in the dynamic optimization is much less. A global dynamic condition number index is proposed and applied to the dynamic optimization design the parallel manipulator. This paper deals with the dynamic manipulability and dynamic optimization of a two degree-of-freedom （DOF） parallel manipulator. The particular velocity and particular angular velocity matrices of each moving part about the part＇s pivot point are derived fi＇om the kinematic formulation of the manipulator, and the inertial force and inertial movement are obtained utilizing Newton-Euler formulation, then the inverse dynamic model of the parallel manipulator is proposed based on the virtual work principle. The general inertial ellipsoid and dynamic manipulability ellipsoid are applied to evaluate the dynamic performance of the manipulator, a global dynamic condition number index based on the condition number of general inertial matrix in the workspace is proposed, and then the link lengths of the manipulator is redesigned to optimize the dynamic manipulability by this index. The dynamic manipulability of the origin mechanism and the optimized mechanism are compared, the result shows that the optimized one is much better. The global dynamic condition number index has good effect in evaluating the dynamic dexterity of the whole workspace, and is efficient in the dynamic optimal design of the parallel manipulator.

关键词： dynamic manipulability dynamic optimization parallel manipulator

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Seismic performance evaluation of steel frame-steel plate shear walls system based on the capacity spectrum method

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2008年第3期9卷 322-329页

作者： Jian-hua shao Qiang GU Yong-kang SHEN College of Civil Engineering Hohai University Nanjing 210098 China Department of Civil Engineering Suzhou University of Science and Technology Suzhou 215011 China

This paper presents some methods that the standard acceleration design response spectra derived from the present China code for seismic design of buildings are transformed into the seismic demand spectra, and that the base shear force-roof displacement curve of structure is converted to the capacity spectrum of an equivalent single-degree-of-freedom （SDOF） system. The capacity spectrum method （CSM） is programmed by means of MATLABT.0 computer language. A dual lateral force resisting system of 10-story steel frame-steel plate shear walls （SPSW） is designed according to the corresponding China design codes. The base shear force-roof displacement curve of structure subjected to the monotonic increasing lateral inverse triangular load is obtained by applying the equivalent strip model to stimulate SPSW and by using the finite element analysis software SAP2000 to make Pushover analysis. The seismic performance of this dual system subjected to three different conditions, i.e. the 8-intensity frequently occurred earthquake, fortification earthquake and seldom occurred earthquake, is evaluated by CSM program. The excessive safety of steel frame-SPSW system designed according to the present China design codes is pointed out and a new design method is suggested.

关键词： Steel frame-steel plate shear walls (SPSW) system Capacity spectrum method (CSM) Seismic demand spectrum Base shear force-roof displacement Seismic performance evaluation

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TOWARDS EXPLORING WHEN AND WHAT PEOPLE REVIEWED FOR THEIR ONLINE SHOPPING EXPERIENCES

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Journal of Systems Science and Systems Engineering 2018年第3期27卷 367-393页

作者： Liangqiang Li hua Yuan Yu Qian Peiji shao School of Management and Economics University of Electronic Science and Technology of China Chengdu 611731 China

Web 2.0 technologies have attracted an increasing number of people with various backgrounds to become active online writers and viewers. As a result, exploring reviewers＇ opinions from a huge number of online reviews has become more important and simultaneously more difficult than ever before. In this paper, we first present a methodological framework to study the ＂purchasing-reviewing＂ behavior dynamics of online customers. Then, we propose a review-to-aspect mapping method to explore reviewers＇ opinions from the massive and sparse online reviews. The analytical and experimental results with real data demonstrate that online customers can be sectioned into groups in accordance with their reviewing behaviors and that people within the same group may have similar reviewing motivations and concerns for an online shopping experience.

关键词： E-commerce online review review dynamics opinion mining

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Parthenolide inhibits proliferation of vascular smooth muscle cells through induction of G_0/G_1 phase cell cycle arrest

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2009年第7期10卷 528-535页

作者： shao-xiang WENG Mei-hua SUI Shan CHEN Jian-an WANG Geng XU Ji MA Jiang SHAN Lu FANG Department of Cardiology the Second Affiliated Hospital School of Medicine Zhejiang University Hangzhou 310009 China Department of Chemical and Biochemical Engineering Zhejiang University Hangzhou 310027 China Department of Pathology and Laboratory Medicine Medical University of South Carolina Charleston SC 29425 USA

Objective： This study is to determine the effect of the natural product parthenolide, a sesquiterpene lactone isolated from extracts of the herb Tanacetum parthenium, on the proliferation of vascular smooth muscle cells （VSMCs）. Methods： Rat aortic VSMCs were isolated and cultured in vitro, and treated with different concentrations ofparthenolide （l 0, 20 and 30 μmol/L）. [^3H]thymidine incorporation was used as an index of cell proliferation. Cell cycle progression and distribution were determined by flow cytometric analysis. Furthermore, the expression of several regulatory proteins relevant to VSMC proliferation including IκBα, cyclooxygenase-2 （Cox-2）, p21, and p27 was examined to investigate the potential molecular mechanism. Results： Treatment with parthenolide significantly decreased the [^3H]thymidine incorporation into DNA by 30%-56% relative to control values in a dose-dependent manner （P〈0.05）. Addition of parthenolide also increased cell population at G0/G1 phase by 19.2%-65.7% （P〈0.05） and decreased cell population at S phase by 50.7%-84.8% （P〈0.05）, which is consistent with its stimulatory effects on p21 and p27. In addition, parthenolide also increased IκBα expression and reduced Cox-2 expression in a time-dependent manner. Conclusion： Our results show that parthenolide significantly inhibits the VSMC proliferation by inducing G0/G1 cell cycle arrest. IκBα and Cox-2 are likely involved in such inhibitory effect ofparthenolide on VSMC proliferation. These findings warrant further investigation on potential therapeutic implications ofparthenolide on VSMC proliferation in vivo.

关键词： Parthenolide Vascular smooth muscle cell (VSMC) Cell proliferation IκBα Cyclooxygenase-2 (Cox-2) p21

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