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Perturbation Solutions for Thermal Process of Honeycomb Regenerator

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Journal of Iron and Steel Research International 2007年第4期14卷 6-10,48页

作者： AI Yuan-fang MEI Chi HUANG guo-dong jiang Shao-iian School of Energy Science and Engineering Central South University Changsha 410083 Hunan China

A parameter perturbation for the unsteady-state heat-transfer characteristics of honeycomb regenerator is presented. It is limited to the cases where the storage matrix has a small wall thickness so that no temperature variation in the matrix perpendicular to the flow direction is considered. Starting from a two-phase transient thermal model for the gas and storage matrix, an approximate solution for regenerator heat transfer process is derived using the multiple-scale method for the limiting case where the longitudinal heat conduction of solid matrix is far less than the convective heat transfer between the gas and the solid. The regenerator temperature profiles are expressed as Taylor series of the coefficient of solid heat conduction item in the model. The analytical validity is shown by comparing the perturbation solution with the experiment and the numerical solution. The results show that it is possible for the perturbation to improve the effectiveness and economics of thermal research on regenerators.

关键词： honeycomb regenerator thermal process asymptotic analysis semi-analytic method

Instability analysis of free deformation zone of cylindrical parts based on hot-granule medium-pressure forming technology

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Transactions of Nonferrous Metals Society of China 2016年第8期26卷 2188-2196页

作者： Miao-yan CAO Chang-cai ZHAO guo-jiang dong Sheng-fu YANG College of Mechanical Engineering Yanshan University Qinhuangdao 066004 China Key Laboratory of Advanced Forging & Stamping Technology and Science Ministry of Education Yanshan University Qinhuangdao 066004 China College of Vehicles and Energy Yanshan University Qinhuangdao 066004 China

The cylindrical part of sheet metal based on hot-granule medium-pressure forming (HGMF) technology was *** stress functions of the free deformation zone and the fracture instability theory were combined to establish the analytical expression of the critical pressure of punch. The results show that the active friction between the granule medium and the sheet metal, as well as the non-uniform internal pressure presented by the solid granule medium, can obviously improve the forming performance of the sheet metal. The critical pressure of punch increases with the increment of the friction coefficient between the granule medium and sheet metal, as well as the plastic strain ratio, whereas it decreases with the increase of the material-hardening exponent. Furthermore, the impact on the critical pressure from high to low order is the plastic strain ratio, the friction coefficient,and material-hardening exponent. The deep-drawing experiment with HGMF technology on AZ31B magnesium alloy sheet verified the instability *** words: hot-granule

关键词： hot-granule medium-pressure forming deep-drawing instability cylindrical part

Noise Effect on the 2D Stochastic Burgers Equation

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Acta Mathematica Sinica,English Series 2024年第9期40卷 2065-2090页

作者： Zhao dong jiang Lun WU guo Li ZHOU RCSDS Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190P.R.China Beijing Normal University-Hong Kong Baptist University United International College Zhuhai 519087P.R.China Guangdong Provincial Key Laboratory of Interdisciplinary Research and Application for Data Science(IRADS) UICZhuhai 519087P.R.China School of Statistics and Mathematics Chongqing University Key Laboratory of Nonlinear Analysis and Its Applications(Chongqing University) Ministry of EducationChongqing 400044P.R.China

By comprehensive utilizing of the geometry structure of 2D Burgers equation and the stochastic noise,we find the decay properties of the solution to the stochastic 2D Burgers equation with Dirichlet boundary ***,the e... 详细信息

关键词： 2D stochastic Burgers equation regularity

Ergodicity of 3D Stochastic Burgers Equation

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Acta Mathematica Sinica,English Series 2024年第2期40卷 498-510页

作者： Zhao dong jiang Lun WU guo Li ZHOU RCSDS Academy of Mathematics and Systems ScienceChinese Academy of SciencesBeijing 100190P.R.China Department of Mathematics Computational FoundrySwansea UniversitySwansea SA18ENUK College of Mathematics and Statistics Chongqing UniversityChongqing 400044P.R.China

3D Burgers equation is an important model for *** is natural to expect the long-time behaviour for this hydrodynamics ***,there is no result about the long-time behaviour for this deterministic ***,if the system is perturbed by stochastic noise,we establish the existence and uniqueness of invariant measure for 3D stochastic Burgers equation.

关键词： 3D stochastic Burgers equations maximum principle ergodicity

Comparative study on forming limit prediction of AA7075-T6 sheet with M−K model and Lou−Huh criterion

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Transactions of Nonferrous Metals Society of China 2020年第6期30卷 1463-1477页

作者： guo-jiang dong Zhi-wei CHEN Zhuo-yun YANG Bo-cheng FAN Hebei Key Laboratory of Special Delivery Equipment Yanshan UniversityQinhuangdao 066004China Key Laboratory of Advanced Forging&Stamping Technology and Science of Ministry of Education of China Yanshan UniversityQinhuangdao 066004China

In order to effectively predict the fracture of AA7075-T6 sheet, the forming limit curves of AA7075-T6 high-strength sheet were drawn according to Morciniak Kuczyski (M K) model and Lou Huh criterion, respectively. The errors between the predicted values of the two theoretical prediction models and experimental values were calculated by error analysis. The forming limit curves were verified by the punch stretch test to evaluate the prediction accuracy of M K model and Lou Huh criterion. The error analysis results show that the mean error of Lou Huh criterion with the optimal parameters for all tensile specimens is 25.04%, while the mean error of M K model for all tensile specimens is 74.24%. The prediction accuracy of Lou Huh criterion in predicting the fracture of AA7075-T6 sheet is higher. The punch stretch test results show that the forming limit curve drawn by Lou Huh criterion can effectively predict the fracture of AA7075-T6 sheet, but the prediction accuracy of M K model is relatively poor.

关键词： ductile fracture criterion M K model forming limit diagram AA7075-T6 sheet

Formability and strengthening mechanism of AA6061 tubular components under solid granule medium internal high pressure forming

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Transactions of Nonferrous Metals Society of China 2018年第2期28卷 226-234页

作者：毕江赵长财杜冰国庆波董国疆燕山大学先进锻压成形技术与科学教育部重点实验室秦皇岛066004 哈尔滨工业大学先进焊接与连接国家重点实验室哈尔滨150001 秦皇岛北方管业有限公司秦皇岛066004 燕山大学车辆与能源学院秦皇岛066004

A new technological process of tube forming was developed, namely solution treatment → granule medium internal high pressure forming → artificial aging. During this process, the mechanical properties of AA6061 tube can be adjusted by heat treatment to satisfy the process requirements and the processing method can also be realized by granule medium internal high pressure forming technology with the features of convenient implementation, low requirement to equipment and flexible design in product. Results show that, at a solution temperature of 560 ℃ and time of 120 min, the elongation of AA6061 increases by 313%, but the strength and the hardness dramatically decrease. At an aging temperature of 180 ℃ and time of 360 min, the strength and hardness of AA6061 alloy are recovered to the values of the as-received alloy. The maximum expansion ratio（MER） of AA6061 tube increases by 25.5% and the material properties of formed tube reach the performances of raw material.

关键词： AA6061 alloy internal high pressure forming heat treatment strengthening mechanism

In situ mitigation strategies for field emission-induced cavity faults using low-level radiofrequency system

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Nuclear Science and Techniques 2022年第11期33卷 46-60页

作者： Feng Qiu Yuan He An-dong Wu Zhen-Long Zhu guo-dong jiang Tian-Cai jiang Zheng Gao Qi Chen Zong-Heng Xue Jin-Ying Ma Cheng-Ye Xu Zi-Qin Yang Gui-Rong Huang Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China School of Nuclear Science and Technology University of Chinese Academy of SciencesBeijing 100049China

In the Chinese ADS front-end demo superconducting radiofrequency linac(CAFe)at the Institute of Modern Physics,a burst-noise signal-triggered cavity fault frequently appears during beam *** events are characterized by a rapid burst noise in the cavity pick-up,which may lead to an unexpected low-level radiofrequency(LLRF)response that eventually causes a cavity *** eliminate the undesirable reaction of the LLRF control loop,we propose a method that uses a burstnoise detection and processing algorithm integrated into the LLRF feedback *** algorithm can prevent undesired regulations in LLRF *** analysis revealed that some burst-noise events did not exhibit measurable energy *** contrast,the other events were accompanied by a rapid loss of cavity stored energy and exhibited similarities to the‘‘E-quench’’phenomena reported in other laboratories.A particle-in-cell simulation indicated that the suspected E-quench phenomenon may be related to a plasma formation process inside the ***,the LLRF algorithm is robust to the two different types of burst-noise events and can significantly mitigate the corresponding cavity faults in CAFe beam commissioning.

关键词： Field emission Flashover E-quench Superconducting LLRF CAFe Plasma formation

Neg-Entropy Mechanism as a Target for Natural Medicines

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Engineering 2024年第7期38卷 11-12页

作者： Tian-Le Gao Hui-Hui guo Jian-dong jiang Institute of Materia Medica Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050China Institute of Medicinal Biotechnology Chinese Academy of Medical Sciences&Peking Union Medical CollegeBeijing 100050China

Current strategies for drug discovery research mainly focus on molecular targets,in which structure biology plays a central role,such as the detailed mechanism of a drug-target *** principle of this approach is the presumed molecular mechanism or genetic background of the disease being *** this approach has brought progress in understanding the mode of action for some drugs,most prevalent illnesses-especially chronic diseases-are multifactorial and present with a group of symptoms,as is often the case in cardiovascular diseases,metabolic disorders,cancers,and so *** newly emerging term“multi-morbidity”(i.e.,multiple co-occurring diseases)describes a grand challenge for this strategy,and successful drug intervention for multimorbidity should be multifaceted[1].So,our research team has shifted its attention to a new direction that views the disease as a whole instead of a single-molecule abnormality,and focusing on drugs with multiple targets.

关键词： drugs diseases cardiovascular

Evaluation of Improved Ultrasonic Nebulizer for Miniature Simultaneous Microwave Plasma Torch Spectrometer

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Chemical Research in Chinese Universities 2006年第3期22卷 297-301页

作者： FENG guo-dong jiang Jie HUAN Yan-fu ZHENG Jian LI Ming CAO Yan-bo JIN Qin-han YU Ai-min Department of Analytical Chemistry College of Chemistry Jilin University Changchun 130021 P. R. China

A new automatic sample solution introduction system for miniature simultaneous microwave plasma torch（MPT） atomic emission spectrometer was developed. The operating parameters were optimized. The detection limits of the spectrometer with an ultrasonic nebulizer for Ag, Al, Ba, Ca, Cr, Cu, Fe, Mg, Mn, Sr, and V are 5-10 times lower than those obtained with a pneumatic nebulizer and are also lower than those obtained by a Model JX-lOlO MPT spectrometer. Two practical samples were analyzed to test the reliability and sensitivity of the system.

关键词： Microwave plasma torch Miniature simultaneous spectrometer Ultrasonic nebulizer Automatic introduction system