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Single-pulse chaotic dynamics of functionally graded materials plate

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Acta Mechanica Sinica 2013年第4期29卷 593-601页

作者： Yu-Gao Huangfu Fang-qi chen College of Mathematics and Information Science Henan Polytechnic University Department of Mathematics Nanjing University of Aeronautics and Astronautics

Single-pulse chaos are studied for a functionally graded materials rectangular plate. By means of the global perturbation method, explicit conditions for the existence of a SiZnikov-type homoclinic orbit are obtained for this sys- tem, which suggests that chaos are likely to take place. Then, numerical simulations are given to test the analytical predic- tions. And from our analysis, when the chaotic motion oc- curs, there are a quasi-period motion in a two-dimensional subspace and chaos in another two-dimensional supplemen- tary subspace.

关键词： Functionally graded materials ~ Single-pulse ~Melnikov's method ~ Homoclinic orbit ~ Numerical simula-tion

Electrical conductivity of hydrous silicate melts and aqueous fluids: Measurement and applications

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Science China Earth Sciences 2016年第5期59卷 889-900页

作者： GUO Xuan chen qi NI HuaiWei CAS Key Laboratory of Crust-Mantle Materials and Environments School of Earth and Space Sciences University of Science and Technology of China

The combination of magnetotelluric survey and laboratory measurements of electrical conductivity is a powerful approach for exploring the conditions of Earth's deep interior. Electrical conductivity of hydrous silicate melts and aqueous fluids is sensitive to composition, temperature, and pressure, making it useful for understanding partial melting and fluid activity at great depths. This study presents a review on the experimental studies of electrical conductivity of silicate melts and aqueous fluids, and introduces some important applications of experimental results. For silicate melts, electrical conductivity increases with increasing temperature but decreases with pressure. With a similar Na^+ concentration, along the calc-alkaline series electrical conductivity generally increases from basaltic to rhyolitic melt, accompanied by a decreasing activation enthalpy. Electrical conductivity of silicate melts is strongly enhanced with the incorporation of water due to promoted cation mobility. For aqueous fluids, research is focused on dilute electrolyte solutions. Electrical conductivity typically first increases and then decreases with increasing temperature, and increases with pressure before approaching a plateau value. The dissociation constant of electrolyte can be derived from conductivity data. To develop generally applicable quantitative models of electrical conductivity of melt/fluid addressing the dependences on temperature, pressure, and composition, it requires more electrical conductivity measurements of representative systems to be implemented in an extensive P-T range using up-to-date methods.

关键词： Silicate melts Aqueous fluids Electrical conductivity Laboratory measurement Partial melting

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承力盘数量对桩周土影响的试验研究

科学技术与工程 2025年第1期25卷 321-328页

作者：牛雷陈亚晴徐丽娜齐晨晖钱永梅吉林建筑大学土木工程学院长春130118 吉林建筑大学交通科学与工程学院长春130118

为了探讨承力盘数量对扩盘桩的承载力及桩周土体的影响,通过自行研制的小型半面桩模型试验设备,采用数字图像相关(digital image correlation,DIC)技术设备实时记录桩周土体变形情况,并以此分析桩周土体位移与破坏特征。试验研究表明,... 详细信息

为了探讨承力盘数量对扩盘桩的承载力及桩周土体的影响,通过自行研制的小型半面桩模型试验设备,采用数字图像相关(digital image correlation,DIC)技术设备实时记录桩周土体变形情况,并以此分析桩周土体位移与破坏特征。试验研究表明,加载时承力盘下土体受压形成压缩区且该区域的影响范围随着荷载增大逐渐变大,同时向两侧土体挤压;承力盘上方裂隙持续发展至最后形成临空区,且该区域随荷载增加而扩大。三盘桩较单盘桩和二盘桩的承载力提升较大,但其荷载-沉降曲线形状较为相似。施加荷载过程中,靠近承力盘和承力盘下方的桩周土体位移变化最明显。因此,研究结果对于承力盘数量对桩周土体影响等相关方向研究做了补充。

关键词：半面桩模型试验扩盘桩承力盘数量竖向承载力土体破坏状态

排放物气候效应指标GWP和GTP的研究进展

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气候变化研究进展 2025年第1期21卷 69-77页

作者：陈琪张华柳丽婷王秋艳周喜讯谢冰中国气象局地球系统数值预报中心北京100081 中国气象科学研究院灾害天气国家重点实验室北京100081 南京信息工程大学南京210044 近地面探测技术重点实验室无锡241035 中国气象局气候预测研究重点开放实验室国家气候中心北京100081

衡量排放物气候效应的指标有两种最为常见:全球增温潜能(GWP)和全球温变潜能(GTP)。这些指标是制定排放政策的基本科学依据,对制造业和相关经济部门的政策制定者有重要的参考价值,同时对理解排放和减排水平对过去和未来气候变化的定量... 详细信息

衡量排放物气候效应的指标有两种最为常见:全球增温潜能(GWP)和全球温变潜能(GTP)。这些指标是制定排放政策的基本科学依据,对制造业和相关经济部门的政策制定者有重要的参考价值,同时对理解排放和减排水平对过去和未来气候变化的定量影响有重要的科学意义。文中围绕IPCC第五和第六次评估报告针对GWP和GTP的讨论,对排放物气候效应指标的基本概念及其30余年的发展史进行了综述,详细介绍了常见排放物气候效应指标GWP和GTP的概念和算法,并系统分析了两者的区别和适用性。GTP与全球平均地表气温变化的关系更密切,因此在评估温室气体对地表气温的影响方面具有潜在优势。然而,GTP也存在一些不确定性,例如气候敏感性因素的影响、地球系统中的热交换以及目标时间点的选择。此外,还介绍了一些新的排放物气候效应指标,并探讨了排放物气候效应指标未来的发展方向。

关键词：排放物气候效应指标全球增温潜能(GWP) 全球温变潜能(GTP)

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Recent progress on surface chemistryⅡ:Property and characterization

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Chinese Chemical Letters 2025年第1期36卷 8-57页

作者： Xin Li Zhen Xu Donglei Bu Jinming Cai Huamei chen qi chen Ting chen Fang cheng Lifeng Chi Wenjie Dong Zhenchao Dong Shixuan Du qitang Fan Xing Fan qiang Fu Song Gao Jing Guo Weijun Guo Yang He Shimin Hou Ying Jiang Huihui Kong Baojun Li Dengyuan Li Jie Li qing Li Ruoning Li Shuying Li Yuxuan Lin Mengxi Liu Peinian Liu Yanyan Liu Jingtao Lü Chuanxu Ma Haoyang Pan JinLiang Pan Minghu Pan Xiaohui qiu Ziyong Shen qiang Sun Shijing Tan Bing Wang Dong Wang Li Wang Lili Wang Tao Wang Xiang Wang Xingyue Wang Xueyan Wang Yansong Wang Yu Wang Kai Wu Wei Xu Na Xue Linghao Yan Fan Yang Zhiyong Yang Chi Zhang Xue Zhang Yang Zhang Yao Zhang Xiong Zhou Junfa Zhu Yajie Zhang Feixue Gao Yongfeng Wang Center for Carbon-based Electronics and Key Laboratory for the Physics and Chemistry of Nanodevices School of ElectronicsPeking UniversityBeijing 100871China Spin-X Institute School of MicroelectronicsSouth China University of TechnologyGuangzhou 511442China School of Materials and Energy Guangzhou Key Laboratory of Low-Dimensional Materials and Energy Storage DevicesGuangdong University of TechnologyGuangzhou 510006China Faculty of Materials Science and Engineering Kunming University of Science and TechnologyKunming 650093China i-Lab CAS Key Laboratory of Nanophotonic Materials and DevicesSuzhou Institute of Nano-Tech and Nano-BionicsChinese Academy of SciencesSuzhou 215123China CAS Key Laboratory of Molecular Nanostructure and Nanotechnology CAS Research/Education Center for Excellence in Molecular SciencesBeijing National Laboratory for Molecular Sciences(BNLMS)Institute of ChemistryChinese Academy of SciencesBeijing 100190China State Key Laboratory for Organic Electronics and Information Displays&Jiangsu Key Laboratory for Biosensors Institute of Advanced MaterialsJiangsu National Synergetic Innovation Center for Advanced MaterialsNanjing University of Posts and TelecommunicationsNanjing 210023China Institute of Functional Nano and Soft Materials(FUNSOM) Jiangsu Key Laboratory for Carbon-Based Functional Materials and DevicesSoochow UniversitySuzhou 215123China Hefei National Research Center for Physical Sciences at the Microscale and Synergetic Innovation Center of Quantum Information and Quantum Physics University of Science and Technology of ChinaHefei 230026China Institute of Physics&University of Chinese Academy of Sciences Beijing 100190China State Key Laboratory of Catalysis Dalian Institute of Chemical PhysicsChinese Academy of SciencesDalian 116023China College of Chemistry Beijing Normal UniversityBeijing 100875China Beijing National Laboratory for Molecular Sciences(BNLMS) College of Chemistry and Molecular EngineeringPeking UniversityBeijing 100871China School

Surface with well-defined components and structures possesses unique electronic,magnetic,optical and chemical *** a result,surface chemistry research plays a crucial role in various fields such as catalysis,energy,materials,quantum,and *** science mainly investigates the correspondence between surface property and *** probe microscopy(SPM)techniques are important tools to characterize surface properties because of the capability of atomic-scale imaging,spectroscopy and manipulation at the single-atom *** this review,we summarize recent advances in surface electronic,magnetic and optical properties characterized mainly by SPM-based *** focus on elucidating theπ-magnetism in graphene-based nanostructures,construction of spin qubits on surfaces,topology properties of surface organic structures,STM-based light emission,tip-enhanced Raman spectroscopy and integration of machine learning in SPM studies.

关键词： Surface chemistry Scanning probe microscopy π-Magnetism Spin qubits Tip-enhanced Raman spectroscopy

Development of a novel fabricating thin-walled TA2 titanium tube via high-frequency induction welding

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Progress in Natural Science:Materials International 2024年第2期34卷 314-322页

作者： Yanfeng Liu qi chen Jibing chen Junsheng Yang Shijie Dong School of Mechanical Engineering Wuhan Polytechnic University Hubei Sanjiang Aerospace Jiangbei Mechanical Engineering Co. Ltd

Due to the problems of low welding efficiency, large heat-affected zone, and poor welding quality in the process of welding thin-walled titanium tubes by argon arc welding, there are few studies on the use of high-frequency induction welding(HFIW) of thin-walled titanium alloy tubes. The evolution law of weld microstructure and mechanical properties of the thin-walled titanium tube needs to be further studied because of rapid welding speed and the small heat-affected zone of HFIW. Therefore, a novel manufacturing method via high-frequency induction welding is proposed in this paper to solve the existing problems. With an industrial-grade titanium TA2 tube(wall's thickness is 0.5 mm) as the research object, a comparative study is conducted in this research to examine the morphology, microstructure, microhardness, and tensile characteristics of welded joints at different welding power. The findings demonstrated a significant efficacy of HFIW in resolving these challenges. The mechanical properties and microstructue of heat-affected zone(HAZ) were characterized. The lowest hardness is measured at202 HV, while the base material was recorded as 184 HV, when the welding speed of HFIW is set at 50 m/***, the heat-affected zone has the highest hardness at 224 HV, a tensile strength of 446.8 MPa and a postfracture elongation of 16%. The results showed that HFIW can not only greatly improve the welding efficiency,significantly improve the microstructure of weld joint and HAZ, and improve the mechanical properties of thinwalled titanium pipe, but also provide a highly feasible welding method for welding ultra-thin-walled pipes.

关键词： Thin-walled tube TA2 titanium High-frequency induction welding Heat-affected zone Microstructure Mechanical property

哌嗪及其衍生物CO_(2)吸收剂的研究进展

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现代化工 2025年第1期45卷 46-50页

作者：孔明梁启晨吴勇刘帅蔡旺锋天津大学化工学院天津300350 安徽兴欣新材料有限公司安徽省企业研发中心安徽池州247260 绍兴兴欣新材料股份有限公司浙江绍兴312300

介绍了哌嗪与CO_(2)反应的机理。总结了单组分哌嗪衍生物、含哌嗪类有机胺的混合胺液吸收剂、哌嗪类有机胺与无机类溶剂混合吸收剂、哌嗪浸渍改性固体类吸附剂捕集CO_(2)的优劣。并对哌嗪类衍生物吸收剂捕集CO_(2)研究提出了展望。

关键词：哌嗪有机胺二氧化碳吸收解吸

Formulation of grain growth diagram in simulated weld HAZ of Ti-microalloyed steel

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Acta Metallurgica Sinica(English Letters) 2009年第4期22卷 308-312页

作者： Chibin GUI qi chen Kun CUI Department of Naval Architecture and Ocean Engineering School of Naval Architecture and Power Engineering Navy University of Engineering Wuhan 430033 China

In this paper, the response of TiN particles to welding thermal cycle and the kinetic behavior of the grain growth in weld heat-affected zone of the Ti-microalloyed steel have been studied by using the simulation technology. Based on the theory of the TiN particle dissolution and coarsening kinetic models in weld thermal cycle and some metallographic data from thermal simulated samples, the grain growth diagram of Ti-microalloyed steel is presented. The experimental data from thermal simulated weld samples agreed well with the value of the diagram predicted.

关键词： Ti-microalloyed steel Grain growth in weld HAZ Simulation technology

Disparities in the Levels of Whole-Blood Epstein-Barr Virus between the Cancer and Non-Cancer Populations in Zhejiang,China

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Biomedical and Environmental Sciences 2024年第9期37卷 993-1002页

作者： qingjun Jia Meichun Zeng qi chen Hangzhou Center for Disease Control and Prevention(Hangzhou Health Supervision Institution) Hangzhou 310021ZhejiangChina Department of Pathology The First Affiliated HospitalCollege of MedicineZhejiang UniversityHangzhou 310003ZhejiangChina

Objective This study aimed to investigate the prevalence of Epstein-Barr virus(EBV)infection in patients with and without *** A total of 26,648 participants who underwent whole-blood EBV DNA(WBEBV)assays between January 1,2020,and August 31,2023,were *** chi-square test was used for categorical data analysis,and R software was used to analyze the differences in EBV DNA load levels and the diagnostic capabilities of *** Positive rates were 10.2%and 25.4%for healthy controls(HC)and patients,*** positivity rate for EBV-associated neoplasms(EN)was the highest at 7.53%,followed by leukemia(Le)at 5.49%.The subgroup analysis showed that the positivity rate for abnormal proliferation or hyperplasia(APH)was 31.9%,followed by 30.5%for *** WBEBV of patients with transplants(TP),especially living-related transplants(LT),was the highest among all *** at diagnosis was used to differentiate between infectious mononucleosis(IM)and chronic active Epstein-Barr virus(CAEBV),with a sensitivity of 67.4%(95%confidence interval[CI]:57.6-75.8)and specificity of 72%(95%CI:63.3-79.3).We conclude that the prevalence of EBV infection is low in the healthy population in this region and that a high EBV load at baseline is more common in LT,IM,and Lymphocyte Leukemia(LL).Conclusion This study used a large-sample survey to characterize the prevalence of whole-blood EBV levels in various diseases,including the stages and *** EBV detection rate was higher in patients with malignant disease than in those with benign *** study provides clinicians with baseline information regarding EBV-associated diseases.

关键词： Epstein-Barr virus Epstein-Barr virus DNA Whole blood Epstein-Barr virus DNA Viral load