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D-CONVERGENCE OF ONE-LEG METHODS FOR STiFF DELAY DiFFERENTiAL EQUATiONS

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Journal of Computational Mathematics 2001年第6期19卷 601-606页

作者： cheng-ming Huang shou-fu Li Hong-yuan Fu Guang-nan chen Department of Mathematics Huazhong University of Science and TechnologyWuhan 430074China Department of Mathematics Xiangtan UniversityXiangtan 411105China institute of Applied Physics and Computational Mathematics Beijing 100088China

Focuses on a study which explored the numerical solution of delay differential equations. Linear stability of numerical methods; Application of one-leg methods; Error analysis.

关键词： nonlinear delay differential equations one-leg methods D-convergence

Reflection Asymmetric Shell Model on the Projected Woods-Saxon+BCS Basis

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Chinese Physics Letters 2001年第12期18卷 1564-1567页

作者： GAO Zao-Chun chen Yong-shou MENG Jie Department of Technical Physics Peking UniversityBeijing 100871 China institute of Atomic Energy P.O.Box 27518Beijing 102413 institute of Theoretical Physics Chinese Academy of SciencesBeijing 100080

The projected Woods-Saxon (WS) quasi-particle states have been used as the bases in the calculation of the reflection asymmetric shell model (RASM). The WS potential has been modified but constrained to give the similar single-particle levels of the standard WS potential. Correspondingly, the multipole interactions in the total RASM Hamiltonian are constructed according to the modified WS potential. The calculated octupole band of 228Th from this approach is in good agreement with experimental data.

关键词： potential Saxon bases

Dynamics of luffing motion of a hydraulically driven shell manipulator with revolute clearance joints

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Defence Technology（防务技术） 2022年第4期18卷 689-708页

作者： chen Zhi-qun Qian Lin-fang chen Guang-song Nie shou-cheng Yin Qiang Yue Cai-cheng School of Mechanical Engineering Nanjing University of Science and TechnologyNanjing210094China Northwest institute of Mechanical and Electrical Engineering Xianyang712099ShaanxiChina China North industry Corporation Beijing100053China

in this study,a modeling method for investigating the dynamic characteristics of a hydraulically driven shell manipulator with revolute clearance joints is *** model accounts for the effect of the clearance,the flexibility of the rotating beam,and the coupled dynamic characteristics of the hydraulic cylinder.A modified contact force model was developed to simulate the physical properties of realistic revolute joints with small clearances,heavy loads,and variable contact stiffnesses and damping coefficients with variations of the *** the strong coupling relationship between the hydraulic cylinder and the flexible beam,a system equation of motion combining the state variables of the hydraulic cylinder and mechanical system was *** complex nonlinear friction force of the hydraulic cylinder motion was constructed using a modified Lu Gre model,and the parameters of the friction model were identified using intelligent identification ***,a test system for the shell manipulator was established to achieve experimental ***,the effects of the clearance size and the stiffness of the cylinder support on the dynamic response were investigated.

关键词： Parameter identification Shell manipulator Hydraulic cylinder Revolute clearance joint

D-CONVERGENCE OF RUNGE-KUTTA METHODS FOR STiFF DELAY DiFFERENTiAL EQUATiONS

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Journal of Computational Mathematics 2001年第3期19卷 259-268页

作者： cheng-ming Huang Hong-yuan Fu shou-fu Li Guang-nan chen institute of Applied Mathematics Academy of Mathematics and Systems SciencesChinese Academy of SciencesBeijing 100080China Graduate School China Academy of Engineering PhysicsBeijing 100088China institute for Computational and Applied Mathematics Xiangtan UniversityXiangtan 411105China Graduate School China Academy of Engineering PhysicsBeijing 100088China

Focuses on a study which examined the numerical solution of delay differential equations (DDE). information on the Runge-Kutta methods for DDE; Results of the D-convergence analysis of Runge-Kutta methods; Details on ... 详细信息

关键词： delay differential equations Runge-Kutta methods D-convergence

一种提高镁合金零部件抗火焰蔓延性的尺寸设计类判据

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Transactions of Nonferrous Metals Society of China 2024年第4期34卷 1123-1135页

作者：胡波韩嘉璇李德江李子昕曾小勤丁文江林占宏金晨赵寿上海交通大学材料科学与工程学院轻合金精密成型国家工程研究中心&金属基复合材料国家重点实验室上海200240 青海盐湖特立镁有限公司西宁810000

基于能量守恒定律提出了一种用于预测棒状镁合金样品火焰蔓延时间的判据,该判据表明火焰蔓延时间主要受合金材料和样品尺寸影响。控制体的初始温度和起燃温度以及样品的S/l_c比值(样品横截面面积/横截面周长)是火焰蔓延时间的决定性因... 详细信息

基于能量守恒定律提出了一种用于预测棒状镁合金样品火焰蔓延时间的判据,该判据表明火焰蔓延时间主要受合金材料和样品尺寸影响。控制体的初始温度和起燃温度以及样品的S/l_c比值(样品横截面面积/横截面周长)是火焰蔓延时间的决定性因素。火焰蔓延时间正比于ΔH(将单位质量的样品从初始温度加热到起燃温度所需的能量)和S/l_c比值,这在Mg-8.5Al-0.5Zn-0.2Mn、Mg-2.7Nd-0.4Zn-0.6Zr和Mg-4.0Y-3.3Nd-0.5Zr镁合金中得到验证。对于尺寸相同的样品,Mg-8.5Al-0.5Zn-0.2Mn合金样品有着最大的ΔH以及最长的火焰蔓延时间;对于材质、长度和横截面面积相同的样品,圆形横截面样品的S/lc比值最大,其抗火焰蔓延性能也最佳。

关键词：镁合金零部件抗火焰蔓延性显微组织尺寸设计判据

High-resolution anatomical and spatial transcriptome analyses reveal two types of meristematic cell pools within the secondary vascular tissue of poplar stem

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Molecular Plant 2023年第5期16卷 809-828页

作者： Juan Du Yichen Wang Wenfan chen Mingling Xu Ruhong Zhou Huixia shou Jun chen State Key Laboratory of Plant Physiology and Biochemistry College of Life SciencesZhejang University866Yu Hangtang RoadHangzhouZhejiang 310058China MOE Key Laboratory of Biosystems Homeostasis&Protection College of Life SciencesZhejang University866 Yu Hangtang RoadHangzhouZhejang 310058China institute of Quantitative Biology College of Life SciencesZhejiang UniversityHangzhouZhejiang 310058China Hangzhou Botanical Garden Taoyuanling RoadHangzhouZhejiang 310013China

The secondary vascular tissue emanating from meristems is central to understanding how vascular plants such as forest trees evolve,grow,and regulate secondary radial ***,the overall molecular characterization of meristem origins and developmental trajectories from primary to secondary vascular tissues in woody tree stems is technically *** this study,we combined high-resolution anatomic analysis with a spatial transcriptome(ST)technique to define features of meristematic cells in a developmental gradient from primary to secondary vascular tissues in poplar *** tissue-specific gene expression of meristems and derived vascular tissue types were accordingly mapped to specific anatomical *** analyses were used to track the origins and changes of meristems throughout the development from primary to secondary vascular ***,two types of meristematic-like cell pools within secondary vascular tissues were inferred based on high-resolution microscopy combined with ST,and the results were confirmed by in situ hybridization of,transgenic trees,and single-cell *** rectangle shape procambium-like(PCL)cells develop from procambium meristematic cells and are located within the phloem domain to produce phloem cells,whereas fusiform shape cambium zone(CZ)meristematic cells develop from fusiform metacambium meristematic cells and are located inside the CZ to produce xylem *** gene expression atlas and transcriptional networks spanning the primary transition to secondary vascular tissues generated in this work provide new resources for studying the regulation of meristem activities and the evolution of vascular plants.A web server(https://***/stRNAPal/)was also established to facilitate the use of ST RNA-seq data.

关键词： poplar stem primary and secondary meristem primary and secondary vascular tissue spatial transcriptome single-cell sequencing

Performance Evaluation of Advanced Wave Energy Converters in the Nearshore Areas of the North indian Ocean

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China Ocean Engineering 2022年第6期36卷 980-993页

作者： WAN Yong ZHANG Wen FAN chen-qing Li Li-gang DAi Yong-shou The College of Oceanography and Space informatics China University of PetroleumQingdao 266580China The Laboratory of Physical Oceanography and Remote Sensing The First Institute of OceanographySOAQingdao 266061China

The 21st Century Maritime Silk Road is a profound measure for mankind,whilst its development is severely restricted by the energy shortage of surrounding *** the core construction area of Maritime Silk Road,the North indian Ocean is rich in wave *** development and utilization of wave energy not only can overcome energy shortage,but also promote communication between peripheral ***,previous researchers often focused on wave energy itself,without combining devices to analyze wave energy ***,we conducted an overall assessment of wave energy resources using 20-year ERA5 data and determined the sites considered as superior for the construction of Wave Energy Farm(WEF)in the coastal *** order to point out which type of Wave Energy Converter(WEC)is best suited for the sites,we carried out the performance evaluation of eight advanced WECs using three parameters:the mean power output,the capacity factor and the capture width *** results show that the performance of Wave Star is superior to other devices,which is supposed to be the primary consideration of the Wave Energy Farms(WEFs)in the future.

关键词： ocean energy wave energy characteristics site selection wave energy converter performance evaluation

硫酸化焙烧——水浸法从镍精矿中同步提取金属及矿相转化

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Transactions of Nonferrous Metals Society of China 2024年第3期34卷 1003-1015页

作者：杜守明牟文宁李丽莹石树正陈欢欢雷雪飞郭瑞罗绍华王乐东北大学材料科学与工程学院沈阳110819 东北大学秦皇岛分校资源与材料学院秦皇岛066004 东北大学秦皇岛分校资源与材料学院河北省电介质与电解质功能材料重点实验室秦皇岛066004 秦皇岛市资源清洁转化与高效利用重点实验室秦皇岛066004 华北理工大学冶金与能源学院唐山063210

提出低温NH_(4)HSO_(4)焙烧—水浸工艺从金川镍精矿中同步提取Ni、Cu和Co,并系统研究硫酸化焙烧和水浸出过程中一些因素对金属提取的影响。结果表明,在优化的焙烧和水浸条件下,95.7%Ni、98.9%Cu和96.8%Co被提取。利用TG-DTA、XRD、SEM和... 详细信息

提出低温NH_(4)HSO_(4)焙烧—水浸工艺从金川镍精矿中同步提取Ni、Cu和Co,并系统研究硫酸化焙烧和水浸出过程中一些因素对金属提取的影响。结果表明,在优化的焙烧和水浸条件下,95.7%Ni、98.9%Cu和96.8%Co被提取。利用TG-DTA、XRD、SEM和EDS等手段分析矿相的转化机理,在NH_(4)HSO_(4)及其分解的SO_(3)和NH3的硫酸化反应下,有价金属被转化为水溶性金属—铵配合物从而得到有效的提取。通过提高浸出温度使铁离子与铵离子结合形成NH_(4)[Fe_(3)(SO_(4))_(2)(OH)_(6)]沉淀可除去浸出液中的杂质铁。在焙烧过程中收集的挥发物为(NH_(4))_(2)SO_(4)和(NH_(4))_(2)SO_(3),可用作硫酸化焙烧的试剂。

关键词：镍精矿 NH_(4)HSO_(4)焙烧同步提取水浸出矿相转化

Effects of nature organic matters and hydrated metal oxides on the anaerobic degradation of lindane,p,p'-DDT and HCB in sediments

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Journal of Environmental Sciences 2003年第5期15卷 618-621页

作者： ZHAO Xu QUAN Xie ZHAO Hui min chen Jing wen chen shou ZHAO Ya zhi School of Environmental Science and Technology Dalian University of TechnologyDalian 116012China.

Effects of natural organic matters(NOM) and hydrated metal oxides(HMO) in sediments on the anaerobic degradation of γ 666, p,p' DDT and HCB were investigated by means of removing NOM and HMO in Liaohe River sediments sequentially. The results showed that the anaerobic degradation of γ 666, p,p' DDT and HCB followed pseudo first order kinetics in different sediments. But, the extents and rates of degradation were different, even the other conditions remained the same. Anaerobic degradation rates of γ 666, p,p' DDT and HCB were 0 020 d -1 , 0 009 d -1 and 0 035 month -1 respectively for the sediments without additional carbon resources. However, with addition of carbon resources, the anaerobic degradation rates of γ 666, p, p ' DDT and HCB were 0 071 d -1 , 0 054 d -1 and 0 088 month -1 in the original sediments respectively. After removing NOM, the rates were decreased to 0 047 d -1 , 0 037 d -1 and 0 066 month -1 ; in the sediments removed NOM and HMO, the rates were increased to 0 067 d -1 , 0 059 d -1 and 0 086 month -1 . These results indicated that NOM in the sediments accelerated the anaerobic degradation of γ 666, p,p' DDT and HCB; the HMO inhibited the anaerobic degradation of γ 666, p,p' DDT and HCB.

关键词： lindane p,p' DDT HCB anaerobic degradation sediments natural organic matters