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Fluctuation with dust of de Sitter ground state of scalar-tensor gravity

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Science China(Physics,Mechanics & Astronomy) 2014年第3期57卷 411-417页

作者： tang yanke ZHANG HongSheng CHEN ChiYi LI XinZhou Department of Physics Dezhou University Shandong Provincial Key Laboratory of Functional Macromolecular Biophysics Dezhou University Center for Astrophysics Shanghai Normal University State Key Laboratory of Theoretical Physics Institute of Theoretical PhysicsChinese Academy of Sciences Hangzhou Normal University Shanghai United Center for Astrophysics Shanghai Normal University

An exact de Sitter solution of scalar-tensor gravity is found in our recent work, in which the non-minimal coupling scalar is rolling along a non-constant potential. Based on this solution, a dust-filled FRW universe is explored in frame of scalar-tensor gravity in this article. The effective dark energy induced by the sole non-minimal scalar can be quintessence-like, phantom-like, and more significantly, can cross the phantom divide. The rich and varied properties of scalar-tensor gravity even with only one scalar is shown.

关键词： scalar tensor gravity de Sitter space dark energy phantom divide

Evidence of Quasi-periodic Oscillation in the Optical Band of the Blazar 1ES 1959+650

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Research in Astronomy and Astrophysics 2022年第11期22卷 14-20页

作者： Fu-Tong Dong Ning Gai yanke tang Yi-Fan Wang Ting-Feng Yi College of Physics and Electronic Information Dezhou UniversityDezhou 253023China Technological Vocational College of Dezhou Dezhou 251200China Key Laboratory of Colleges and Universities in Yunnan Province for High-energy Astrophysics Department of PhysicsYunnan Normal UniversityKunming 650500China

We analyzed the optical monitoring data in the R band of Te V blazar 1ES 1959+650 from 2002 to 2018,and provided evidence of a quasi-periodic oscillation in this *** light curve shows a stable and persistent periodicity at~540 days,detected by the Lomb–Scargle periodogram,Jurkevich and weighted wavelet z-transform *** red noise power spectrum was estimated using the PSRESP method,and this period was found to be at>3σsignificance *** are also two possible periodicities at~268 and~1100 days detected by all three ***,their significance levels are relatively low,and thus these two periods cannot be verified by the present *** discuss several possible physical models that could explain the periodic variability in this object.

关键词： galaxies:active methods:numerical galaxies:individual(1ES 1959+650)

Stellar structure and evolutionary and Asteroseismology

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Stellar structure and evolutionary and Asteroseismology

RELATIONSHIP BETWEEN MORPHOLOGY AND MECHANICAL PROPERTIES OF COPPER-IN-HYDROPHILIC POLYMER GRADIENT COMPOSITE FILM(CPGCF)

2010粒子物理宇宙学研讨会

作者： yanke tang Key Lab of Biophysics in Universities of Shandong & Department of physics, Dezho uUniversity,China

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RELATIONSHIP BETWEEN MORPHOLOGY AND MECHANICAL PROPERTIES OF...

基于双中子星引力波标准汽笛法测量的哈勃参量对于宇宙学参数的限制能力的预言

Third East Asian Polymer Conference

作者： Jianguo tang, yanke Che, Haiyan Liu, and Yao Wang Functional Composite Materials Laboratory, College of Chemical Engineering, Qingdao University, Qingdao 266071, P. R. China,

Gradient materials are considered by the morphological structure that the concentrations of two elementary components, such as polymers, metals, or ceramics, change gradually on their cross-section. The properties and functions of those materials correspond to the position on cross-section. This gradient morphology is quite effective to dissolve interface problems. Most successful examples concerned about metal-ceramic and metal-metal composites. For example, gradient metal-matrix composites offer the advantage of continuously varying mechanical and thermophysical properties such as strength, thermal diffusivity and coefficient of thermal ***, although in the database of web of science there are more than 1200 publications corresponding

关键词： gradient morphology electrochemical polyvinyl alcohol Introduction

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北京师范大学学报（自然科学版） 2019年第2期55卷 185-193页

作者：刘洋万昊宜张同杰唐延柯北京师范大学天文学系北京100875 中国科学院国家天文台北京100012 德州学院天文科学研究院山东德州253023

展示了一种新的测量哈勃参数(H(z))的方法的应用,并用定义品质因子的方式对其所得H(z)进行了评估.这种测量H(z)的方法基于对双中子星系统的引力波汽笛法的分析,其中利用了光度距离(dL)的各向异性.引力波的成功探测预示着引力波标准汽笛... 详细信息

展示了一种新的测量哈勃参数(H(z))的方法的应用,并用定义品质因子的方式对其所得H(z)进行了评估.这种测量H(z)的方法基于对双中子星系统的引力波汽笛法的分析,其中利用了光度距离(dL)的各向异性.引力波的成功探测预示着引力波标准汽笛法潜在的可能性.在此之前对其相应效果进行预言和研究是十分必要的.把这种方法应用在几个比较主流的引力波探测项目上,并进行Fisher Matrix的计算,包括advanced LIGO(aLIGO)、Einstein telescope(ET)、DECIGO等.结果显示,aLIGO和ET测得的H(z)精度都比较差,而DECIGO测得的H(z)显示出良好的精度.利用DECOIGO得到的H(z)的相对误差信息,对H(z)进行模拟,然后用贝叶斯定理对宇宙学参量进行预言,最后利用画contour图和计算品质因子(FoM)方法评估出其限制宇宙学参量的能力.对于DECIGO 3a观测的引力波标准汽笛法,其相应H(z)数据的品质因子为170.82.如果进行10a期的观测,其相应H (z)数据的品质因子更是高达569.42.显示出引力波标准汽笛法的极大前景和潜力.

关键词：光度距离各向异性引力波标准汽笛法双中子星系统哈勃参量宇宙学参量

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欧洲平移式驮背运输发展经验及启示

铁道货运 2024年第1期42卷 58-66页

作者：陈诚唐浩裴程姚彦珂许植深中国铁道科学研究院集团有限公司运输及经济研究所北京100081 中铁快运股份有限公司多式联运部北京100055

驮背运输是多式联运的有效组织模式之一,欧洲驮背运输已经形成自装卸式、吊装式和平移式多种模式。平移驮背运输模式是近年来新兴的组织模式,具有便捷换装、绿色环保、运维成本低等特点。分析欧洲CargoBeamer公司平移式驮背运输网络、... 详细信息

驮背运输是多式联运的有效组织模式之一,欧洲驮背运输已经形成自装卸式、吊装式和平移式多种模式。平移驮背运输模式是近年来新兴的组织模式,具有便捷换装、绿色环保、运维成本低等特点。分析欧洲CargoBeamer公司平移式驮背运输网络、场站设施、车辆装备和货运产品情况,结合我国2个驮背运输示范项目的开展情况,分析我国铁路驮背运输在载运装备空间、装卸效率、全程运输成本等方面存在的问题,对比分析自装卸式、吊装式和平移式驮背运输在载用装备、作业效率、场地设施、组织管理方面的特点,最后结合我国货运发展环境从运输距离、目标市场、场站管理、车辆装备和低碳环保等方面提出欧洲平移式驮背运输模式对我国的启示。

关键词：欧洲平移式驮背运输 CargoBeamer 发展经验换装换轨

A visco-elastoplastic constitutive model of aircraft polymethylmethacrylate related to strain rate and temperature

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Chinese Journal of Aeronautics 2023年第6期36卷 435-445页

作者： Bo ZHANG yanke LIU Haoyu YU Yuansong ZENG Lihui LANG Yong LI School of Mechanical Engineering and Automation Beihang UniversityBeijing 100191China Departmentof Material Application Researching AVIC Manufacturing Technology InstituteBeijing 00024China

The visco-elastoplastic mechanical behavior related to the applied strain rate and temperature around the glass transition temperature of Polymethylmethacrylate(PMMA)has been systematically *** uniaxial tensile test was performed at strain rate and temperature rangs 1.0×10^(-4)-1.0×10^(-2)s^(-1)and 363-393 K,respectively,and the Dynamic Mechanical Analysis(DMA)test was carried out between 363 K and 413 K at various ***,the robust complex constitutive model considering the temperature and strain rate effect is proposed.A nonlinear viscoelastic model is established to describe the viscoelastic response on the basis of the Zhu-Wang-tang(ZWT)model and the time temperature equivalence principle,including the dependence of strain rate and *** the yield stress,the cooperative model is *** viscoplastic mechanical response is manifested as the competition performance of the softening deformation and hardening *** predicted mechanical responses maintain good consistency with the experimental results,indicating that the visco-elastoplastic constitutive model proposed can accurately predict the mechanical behavior of PMMA materials within the imposed strain rate and near the glass transition temperature range.

关键词： Constitutive model Mechanical response Polymethylmethacrylate Viscoelastic Viscoplastic

基质金属蛋白酶-3促进骨肉瘤MG-63细胞的增殖、侵袭及其可能的机制

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中国肿瘤生物治疗杂志 2015年第2期22卷 214-219页

作者：江摩郑燕科余家明徐鹏安汤善华解放军第184医院骨科江西鹰潭335000

目的:研究基质金属蛋白酶-3(matrix metalloproteinase-3,MMP-3)对骨肉瘤细胞增殖、侵袭的影响,并初步探讨MMP-3促进骨肉瘤侵袭和转移的机制。方法:收集2013年1月1日至2013年11月1日期间解放军第184医院骨科收治的骨肉瘤患者40例和健康... 详细信息

目的:研究基质金属蛋白酶-3(matrix metalloproteinase-3,MMP-3)对骨肉瘤细胞增殖、侵袭的影响,并初步探讨MMP-3促进骨肉瘤侵袭和转移的机制。方法:收集2013年1月1日至2013年11月1日期间解放军第184医院骨科收治的骨肉瘤患者40例和健康人40名的血液标本,ELISA法检测其中MMP-3含量,并采用SPSS软件分析MMP-3含量与骨肉瘤Enneking分期的相关性。RT-PCR分别检测不同骨肉瘤细胞株U2-OS、HOS-143b、MG-63中MMP-3的表达。MTT法、Transwell侵袭实验观察50、100、200 ng/ml MMP-3刺激或转入MMP-3-shRNA慢病毒(MOI=50、100、200)对MG-63细胞增殖和侵袭的影响,Western blotting方法检测MMP-3过表达或沉默对MG-63细胞中侵袭、转移相关的蛋白p-AKT、核蛋白NF-κB表达的影响。结果:骨肉瘤患者血清中MMP-3的含量高于正常人(F=186.4,P=0.000);且MMP-3含量与骨肉瘤Enneking分期成正相关(r=0.736,P=0.043)。与其他3株细胞相比,MG-63细胞株中MMP-3表达最高(t=5.12,P<0.05)。MMP-3刺激导致MG-63细胞内MMP-3过表达,p-AKT和核内NF-κB表达升高,并促进MG-63细胞的增殖和侵袭;转入MMP-3-shRNA慢病毒导致MMP-3表达沉默,p-AKT和核内NF-κB表达降低,抑制MG-63细胞的增殖和侵袭。结论:MMP-3可能通过增加AKT磷酸化水平和促进NF-κB核转位来促进骨肉瘤细胞的增殖和侵袭。

关键词：基质金属蛋白酶-3 骨肉瘤 MG-63细胞侵袭增殖 AKT磷酸化 NF-κB核转位

Paecilomyces variotii extracts（ZNC） enhance plant immunity and promote plant growth

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Paecilomyces variotii extracts（ZNC） enhance plant immunity...