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Effects of samarium content on microstructure and mechanical properties of Mg–0.5Zn–0.5Zr alloy

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Journal of Materials science & technology 2019年第7期35卷 1368-1377页

作者： Kai Guan Fanzhi Meng Pengfei Qin Qiang Yang Dongdong zhang Baishun Li Wei Sun Shuhui Lv Yuanding Huang Norbert Hort jian Meng State Key Laboratory of Rare Earth Resource Utilization. Changchun Institute of Applied Chemistry Chinese Academy of Science Changchun 130022 university of science & technology of china Hefei 230026China school of Materials science and Engineering Changchun University of Science and TechnologyChangchun 130022China Key Laboratory of Superlight Material and Surface technology Ministry of EducationCollege of Material Science and Chemical EngineeringHarbin Engineering UniversityHarbin 150001China MagIC-Magnesium Innovation Centre Helmholtz-Zentrum GeesthachtMax-Planck Strasse 121502CeesthachtGermany

Effects of samarium (Sm) content (0, 2.0, 3.5, 5.0, 6.5 wt%) on microstructure and mechanical proper-ties of Mg-0.5Zn-0.5 Zr alloy under as-cast and as-extruded states were thoroughly investigated. Results indicate that grains of the as-cast alloys are gradually refined as Sm content increases. The dominant intermetallic ph^se changes from Mg3Sm to Mg4iSm5 till Sm content exceeds 5.0 wt%. The dynami-cally precipitated intermetallic phase during hot-extrusion in dll Sm-containing alloys is Mg3Sm. The intermetallic particles induced by Sm addition could act as heterogeneous nucleation sites for dynamic recrystallization during hot extrusion. They promoted dynamic recrystallization via the particle stim-ulated nucleation mechanism, and resulted in weakening the basal texture in the as-extruded alloys. Sm addition can significantly enhance the strength of the as-extruded Mg-0.5Zn-0.5Zr alloy at room temperature, with the optimal dosage of 3.5 wt%. The optimal yield strength (YS) and ultimate tensile strength (UTS) are 368 MPa and 383 MPa, which were enhanced by approximately 23.1% and 20.8% com-pared with the Sm-free alloy, respectively. Based on microstructural analysis, the dominant strengthening mechanisms are revealed to be grain boundary strengthening and dispersion strengthening.

关键词： Magnesium alloys Samarium Transmission electron microscopy (TEM) Microstructure Mechanical properties

Murine calcium-activated chloride channel family member 3 induces asthmatic airway inflammation independently of allergen exposure

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Chinese Medical Journal 2013年第17期126卷 3283-3288页

作者： MEI Li HE Li WU Si-si zhang Bo XUYong-jian zhang Zhen-xiang ZHAO jian-ping zhang Hui-lan Department of Respiratory Medicine Tongji Hospital of Tongji Medical College Huazhong University of Science and Technology Wuhan Hubei 430030 China Department of Respiratory Medicine Jingzhou Central Hospital Jingzhou Hubei 434020 China

Background Expression of murine calcium-activated chloride channel family member 3 （mCLCA3） has been reported to be increased in the airway epithelium of asthmatic mice challenged with ovalbumin （OVA）. However, its role in asthmatic airway inflammation under no OVA exposure has not yet been clarified. Methods mCLCA3 plasmids were transfected into the airways of normal BALB/c mice. mCLCA3 expression and airway inflammation in mouse lung tissue were evaluated. Cell differentials and cytokines in bronchoalveolar lavage fluid （BALF） were analyzed. The expression of mCLCA3 protein and mucus protein mucin-5 subtype AC （MUC5AC） were analyzed by Western blotting. The mRNA levels of mCLCA3, MUC5AC and interleukin-13 （IL-13） were determined quantitatively. Results mCLCA3 expression was not detected in the control group while strong immunoreactivity was detected in the OVA and mCLCA3 plasmid groups, and was strictly localized to the airway epithelium. The numbers of inflammatory cells in lung tissue and BALF were increased in both mCLCA3 plasmid and OVA groups. The protein and mRNA levels of mCLCA3 and MUC5AC in the lung tissue were significantly increased in the mCLCA3 plasmid and OVA groups compared to the control group. The level of IL-13, but not IL-4, IL-5, IFN-y, CCL2, CCL5 or CCL11, was significantly increased compared with control group in BALF in the mCLCA3 plasmid and OVA groups. The level of IL-13 in the BALF in the mCLCA3 plasmid group was much higher than that in the OVA group （P 〈0.05）. The level of mCLCA3 mRNA in lung tissue was positively correlated with the levels of MUC5AC mRNA in lung tissue, IL-13 mRNA in lung tissue, the number of eosinophils in BALF, and the content of IL-13 protein in BALE The level of IL-13 mRNA in lung tissue was positively correlated with the number of eosinophils in BALF and the level of MUC5AC mRNA in lung tissue. Conclusion These findings suggest that increased expression of a single-gene, mCLCA3, could simulate an asthma attack, a

关键词： murine calcium-activated chloride channel family member 3 asthma inflammation

Stability control measures for roof cutting and NPR supporting of mining roadways in fault areas of kilometre-deep coal mine

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Journal of Mountain science 2023年第10期20卷 3051-3065页

作者： SUN Xiao-ming WANG jian zhang Yong ZHAO Wen-chao GUO Zhi-biao HE Man-chao CHEN Feng MIAO Cheng-yu State Key Laboratory for Geomechanics and Deep Underground Engineering China University of Mining and Technology(Beijing)Beijing 100083China school of Mechanics and Civil Engineering China University of Mining and Technology(Beijing)Beijing 10oo83China school of Civil Engineering Nanyang Institute of TechnologyNanyang 4730ooChina

The study focuses on the stability control measures for mining roadways in fault zones of deep mines,using Daqiang Coal Mine as a case *** control system under consideration,referred to as"pre-splitting cutting roof+NPR anchor cable"(PSCR-NPR),is subjected to scrutiny through theoretical analysis,numerical modelling,and field ***,a comprehensive analysis is undertaken to evaluate the stability control mechanism of this particular *** study provides evidence that the utilization of deep-hole directional energy-concentrated blasting facilitates the attainment of directional roof cutting in *** aforementioned procedure leads to the formation of a uniform structural surface on the roof of the roadway and causes modifications in the surrounding geological *** examination of the lateral abutment pressure and shear stress distribution,both prior to and subsequent to roof cutting,indicates that the implementation of pre-splitting techniques leads to a noteworthy reduction in *** proposition of incorporating the safety factor Q for roof cutting height is suggested as a method to augment comprehension of the pressure relief phenomenon in the field of *** analysis of numerical simulation has indicated that the optimal pressure relief effect of a mining roadway in a fault area is attained when the value of Q is *** NPR anchor cable exhibits noteworthy characteristics,including a high level of prestress,continuous resistance,and substantial *** the excavation of the roadway,a notable reduction in radial stress occurs,leading to the reinstatement of the three-phase stress state in the surrounding *** restoration is attributed to the substantial prestress exerted on the radial *** termination point of the NPR anchor cable is strategically positioned within a stable rock formation,allowing for the utilization of the mechanical characteristics of the deep stable rock *** posi

关键词： Kilometre-deep mine Fault Mining roadway Pre-splitting cutting roof High pre-stress NPR anchor cable

Efficient preparation of trans-α,β-unsaturated aldehydes from saturated aldehydes by oxidative enamine catalysis

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science china Chemistry 2011年第12期54卷 1932-1936页

作者： zhang ShiLei XIE HeXin SONG AiGuo WU DeYan ZHU Jin ZHAO SiHan LI jian YU XinHong WANG Wei Department of Chemistry ＆ Chemical Biology University of New Mexico MSC03 2060 NM 87131 USA school of Pharmacy East China University of Science ＆ Technology Shanghai 200237 China

A mild and highly efficient amine-catalyzed, IBX-mediated oxidation of aldehydes to （E） selective a, β-unsamrated aldehydes has been achieved in good yields. The process features a new oxidation of enamines to imin... 详细信息

关键词： aldehydes enals enamines IBX oxidative enamine catalysis

牌/麻将类智力运动对老年人焦虑的影响:基于第8轮CLHLS数据

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中国健康心理学杂志 2024年第6期32卷 807-814页

作者：张思奇郭凯林陆梦琦王军利杨剑中国矿业大学体育学院江苏徐州221116 安徽新华学院艺术学院福建师范大学体育科学学院安徽财经大学会计学院华东师范大学体育与健康学院

目的:分析牌/麻将类智力运动对我国老年人焦虑的影响,为老年人心理健康保障提供理论参考。方法:基于中国老年健康影响因素跟踪调查项目第8轮获得的全国数据,利用Logistic回归分析牌/麻将类智力运动对老年人焦虑的影响,辅以更换模型与变... 详细信息

目的:分析牌/麻将类智力运动对我国老年人焦虑的影响,为老年人心理健康保障提供理论参考。方法:基于中国老年健康影响因素跟踪调查项目第8轮获得的全国数据,利用Logistic回归分析牌/麻将类智力运动对老年人焦虑的影响,辅以更换模型与变量以及倾向得分匹配法进行稳健性检验。结果:我国老年人焦虑检出率为11.80%、牌/麻将类智力运动参与度为19.04%。牌/麻将类智力运动参与可降低老年人焦虑风险,控制其余因素后,发现几乎每天参与牌/麻将类智力运动的老年人,患焦虑风险降低了9.3%(系数:-0.093,P<0.05);亚组分析结果显示,牌/麻将类智力运动更有利于降低男性(系数:-0.121,P<0.05)、城镇(系数:-0.102,P<0.05)、无老伴(系数:-0.149,P<0.01)、独居(系数:-0.217,P<0.05)、有养老保险(系数:-0.118,P<0.05)以及经常参加体育锻炼(系数:-0.125,P<0.05)老年人焦虑风险。结论:牌/麻将类智力运动参与有助于降低老年人的焦虑风险,同时不同特征老年人间存在差异。

关键词：智力运动麻将焦虑 Logistic回归分析中国老年健康影响因素跟踪调查老年人

Non-monotonic influence of a magnetic field on the electrochemical behavior of Fe_(78)Si_9B_(13) glassy alloy in NaOH and NaCl solutions

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International Journal of Minerals,metallurgy and Materials 2014年第10期21卷 1009-1018页

作者： Hong-di zhang Xiao-yu Li Jing Pang Li-juan Yin Hai-jian Ma Ying-jie Li Yan Liu Wei-min Wang Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials (Ministry of Education) Shandong University Qingdao Yunlu Energy technology Co. Ltd. school of Mechanical and Electrical Engineering Weifang University

The corrosion behavior and microstructure of Fe78Si9B13 glassy alloy in NaOH and NaCl solutions under a 0.02-T magnetic field were investigated through electrochemical testing and scanning electron microscopy （SEM）. The current-density prepeak （PP） in the anodic polarization curves in low-concentration NaOH solutions （classified as type I） tends to disappear when the NaOH concentration is increased to 0.4 mol/L and the magnetic field is applied. Under the magnetic field, the height of the second current-density peak is increased in low-concentration NaOH solutions （type I） but decreased in high-concentration NaOH solutions （type Ⅱ）. The non-monotonic effect of the magnetic field was similarly observed in the case of polarization curves of samples measured in NaCl solutions, Ring-like corroded patterns and round pits are easily formed under the magnetic field in NaOH and NaC1 solutions. These experimental results were discussed in terms of the magnetohydrodynamic （MHD） effect.

关键词： amorphous alloys electrochemical behavior magnetic field anodic polarization micrographs

Third generation of vortex identification methods:Omega and Liutex/Rortex based systems

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Journal of Hydrodynamics 2019年第2期31卷 205-223页

作者： Chaoqun Liu Yi-sheng Gao Xiang-rui Dong Yi-qian Wang jian-ming Liu Yu-ning zhang Xiao-shu Cai Nan Gui Department of Mathematics University of Texas at ArlingtonArlington 76019TexasUSA College of Energy and Power Engineering University of Shanghai for Science and TechnologyShanghai 200093China school of Aerospace Engineering Tsinghua UniversityBeijing 100084China school of Mathematics and Statistics Jiangsu Normal UniversityXuzhou 221116China Key Laboratory of Condition Monitoring and Control for Power Plant Equipment(Ministry of Education) School of EnergyPower and Mechanical EngineeringNorth China Electric Power UniversityBeijing 102206China Institute of Nuclear and New Energy technology Collaborative Innovation Center of Advanced Nuclear Energy TechnologyKey Laboratory of Advanced Reactor Engineering and Safety of Ministry of EducationTsinghua UniversityBeijing 100084China

A vortex is intuitively recognized as the rotational/swirling motion of fluids,but a rigorous and universally-accepted definition is still not *** tube/filament has been regarded equivalent to a vortex since Helmholtz proposed the concepts of vorticity tube/filament in 1858 and the vorticity-based methods can be categorized as the first generation of vortex identification *** the last three decades,a lot of vortex identification methods,including 0,A,and Aci criteria,have been proposed to overcome the problems associated with the vorticity-based *** of these criteria are based on the Cauchy-Stokes decomposition and/or eigenvalues of the velocity gradient tensor and can be considered as the second generation of vortex identification *** from 2014,the Vortex and Turbulence Research Team at the university of Texas at Arlington(the UTA team)focus on the development of a new generation of vortex identification *** first fruit of this effort,a new Omega(/2)vortex identification method,which defined a vortex as a connected region where the vorticity overtakes the deformation,was published in *** 2017 and 2018,a Liutex(previously called Rortex)vector was proposed to provide a mathematical definition of the local rigid rotation part of the fluid motion,including both the local rotational axis and the rotational ***/Rortex is a new physical quantity with scalar,vector and tensor forms exactly representing the local rigid rotation of ***,a decomposition of the vorticity to a rotational part namely Liutex/Rortex and an anti-symmetric shear part(RS decomposition)was introduced in 2018,and a universal decomposition of the velocity gradient tensor to a rotation part(7?)and a non-rotation part(NR、was also given in 2018 as a counterpart of the traditional Cauchy-Stokes *** in early 2019,a Liutex/Rortex based Omega method called Omega-Liutex,which combines the respective advantages o

关键词： Vortex definition vortex identification Omega Liutex/Rortex direct numerical simulation turbulence

Re-evaluating Transarterial Chemoembolization Failure/Refractoriness:A Survey by Chinese College of Interventionalists

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Journal of Clinical and Translational Hepatology 2021年第4期9卷 521-527页

作者： Bin-Yan Zhong Wan-Sheng Wang Shen zhang Hai-Dong Zhu Lei zhang jian Shen Xiao-Li Zhu Gao-Jun Teng Cai-Fang Ni Department of Interventional Radiology the First Affiliated Hospital of Soochow UniversitySuzhouJiangsuChina Center of Interventional Radiology&Vascular Surgery Department of RadiologyZhongda HospitalMedical SchoolSoutheast UniversityNanjingJiangsuChina

Background and Aims:The recognition of transarterial chemoembolization(TACE)failure/refractoriness among Chinese clinicians remains *** an online survey conducted by the Chinese College of Interventionalists(CCI),the aim of this study was to explore the recognition of TACE failure/refractoriness and review TACE application for hepatocellular carcinoma(HCC)treatment in clinical ***:From 27 August 2020 to 30 August 2020 during the CCI 2020 annual meeting,a survey with 34 questions was sent by email to 264 CCI clinicians in china with more than 10 years of experience using TACE for HCC ***:A total of 257 clinicians participated and responded to the *** participants agreed that the concept of“TACE failure/refractoriness”has scientific and clinical significance(n=191,74.3%).Nearly half of these participants chose TACE-based combination treatment as subsequent therapy after so-called TACE failure/refractoriness(n=88,46.1%).None of the existing TACE failure/refractoriness definitions were widely accepted by the participants;thus,it is necessary to re-define this concept for the treatment of HCC in china(n=235,91.4%).Most participants agreed that continuing TACE should be performed for patients with preserved liver function,presenting portal vein tumor thrombosis(n=242,94.2%)or extrahepatic spread(n=253,98.4%),after the previous TACE treatment to control intrahepatic lesion(s).Conclusions:There is an obvious difference in the recognition of TACE failure/refractoriness among Chinese clinicians based on existing *** work should be carried out to re-define TACE failure/refractoriness.

关键词： Hepatocellular carcinoma TACE Failure Refractoriness Survey

连续退化和随机冲击下基于状态的结构维修策略优化（英文）

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浙江大学学报（英文版）A辑：应用物理与工程 2019年第4期20卷 272-289页

作者： Xiao-sheng zhang jian-qiao CHEN Jun-hong WEI Hubei Key Laboratory for Engineering Structural Analysis and Safety Assessment Department of MechanicsHuazhong University of Science and Technology

目的:结构在使用过程中,其性能往往发生劣化而导致其安全性能(可靠度)不断降低。本文旨在探讨结构在连续退化和冲击荷载共同作用下,其可靠度随时间的变化情况。此外,研究结构的最佳维修策略,使其在满足可靠度约束条件的同时,将平均费用... 详细信息

目的:结构在使用过程中,其性能往往发生劣化而导致其安全性能(可靠度)不断降低。本文旨在探讨结构在连续退化和冲击荷载共同作用下,其可靠度随时间的变化情况。此外,研究结构的最佳维修策略,使其在满足可靠度约束条件的同时,将平均费用降到最低。创新点:1.在连续退化和冲击荷载的共同影响下,建立结构时变可靠度计算模型。2.在前述可靠度分析的基础上,建立基于状态维修的非周期检测模型;基于剩余使用寿命检测策略,确定检测时间,并确定系统的最优维护策略,旨在将平均维护成本率降至最低。3.针对无限时间域和有限时间域,分别确定对应的最佳维修策略。方法:1.通过理论推导,构建结构时变可靠度计算公式(公式(13)),分析各参数与可靠度之间的变化关系(图4)。2.通过仿真模拟,运用蒙特卡洛法确定结构在使用过程中的最佳维修策略(图5和6)。结论:1.与仅考虑连续退化的情况相比,随机冲击荷载的存在,使得系统的可靠度降低,更容易发生失效。2.冲击载荷的存在,对最佳维修策略具有显著影响。3.有限时间域的最优解与无限时间域的最优解之间存在很大的不同,因此,有必要对这两种情况分别进行研究。

关键词：软失效硬失效剩余寿命可靠度维修成本率有限时域