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“一带一路”倡议下的我国海外投资可持续性研究

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经济问题 2022年第7期 35-43页

作者：姜作利姜美玲山东大学法学院山东济南250014 济宁医学院马克思主义学院山东济宁272067

投资是发展的重要动力,监管不当会对东道国经济、社会和环境产生巨大的影响,从而导致东道国为了保护本国的经济利益而中断海外投资项目的发展,这从本质上不利于一国海外投资的可持续发展,这就意味着必须要规范我国海外投资者的投资行为... 详细信息

投资是发展的重要动力,监管不当会对东道国经济、社会和环境产生巨大的影响,从而导致东道国为了保护本国的经济利益而中断海外投资项目的发展,这从本质上不利于一国海外投资的可持续发展,这就意味着必须要规范我国海外投资者的投资行为,提高其在“一带一路”沿线国家和地区的适应能力,因此,总结海外投资政策及法律中可持续发展原则在规范和指引海外投资行为的具体内容尤为关键,并且分析发现虽然我国的海外投资政策对于海外投资可持续发展的作用巨大,但是整体不够体系化和规范化。基于此,要构建海外投资法律制度体系,设立可持续发展基本原则,促进“优质投资”,做好海外投资可持续性宣传和危机公关,实现东道国可持续性减贫探索的新路径,以期待更好地实现“一带一路”倡议下海外投资的可持续发展目标。

关键词：海外投资投资可持续性人类命运共同体可持续发展绿色发展

Mechanical Properties of a Low-thermal-expansion Aluminum/Silicon Composite Produced by Powder Metallurgy

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Journal of Materials Science & Technology 2014年第4期30卷 417-422页

作者： Y.Q.Liu S.H.Wei J.Z.Fan Z.L.Ma T.zuo National Engineering & Technology Research Center for Nonferrous Metal Matrix Composites Beijing General Research Institute for Nonferrous Metals

AI matrix composite containing high volume fraction silicon has been promising candidate for lightweight and low-thermal-expansion components. Whereas, optimization of its mechanical properties still is an open challenge. In this article, a flexile powder metallurgy processing was used to produce a fully dense AI-4.0Cu （wt%） alloy composite reinforced with 65 vol.% Si particles. In this composite, Si particles were homogenously distributed, and the particle size was refined to the range of 3-15 μm. Tensile and flexural strength of the composite were 282 and 455 MPa, respectively, about 100% and 50% higher than the best properties reported in literature. The measured fracture toughness of the composite was 4.90 MPa m1/2. The improved strength of 65%Si/AI was attributed to the optimized particle characteristics and matrix properties. This investigation is expected to provide a primary understanding of the mechanical behaviors of Si/AI composites, and also promote the structural applications of this low-thermal-expansion material.

关键词： Aluminum matrix composite Powder metallurgy Mechanical properties Coefficient of thermal expansion Fracture

Synthesis and properties of tetrathiafulvalene-porphyrin assemblies

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Frontiers of Chemical Science and Engineering 2011年第4期5卷 422-428页

作者： Meijiang LI Rui HUANG Changzhi WU Hujin zuo Guoqiao LAI Yongjia SHEN Key Laboratory of Organosilicon Chemistry and Material Technology of Ministry of Education Hangzhou Normal UniversityHangzhou 310012China Laboratory for Advanced Materials and Institute of Fine Chemicals East China University of Science&TechnologyShanghai 200237China

Two donor-σ-acceptor molecular systems incorporating tetrathiafulvalene(TTF)and tetraphenylpor-phyrin(TPP)units,TTF-TPP(dyad 1)and TTF-TPP-TTF(triad 2),were *** dyad 1 and triad 2 and their synthetic intermediates have been characterized by 1H nuclear magnetic resonance(1H NMR)and mass spectro-graphy(MS).Their ultraviolet and visible spectroscopy(UV-Vis)and cyclic voltammetry(CV)showed negligible intramolecular charge transfer interaction in their ground ***ﬂuorescence intensity was strongly quenched compared with TPP,which implied the photoinduced electron transfer occurred from the TTF unit to the TPP unit in the excited *** the other hand,theirﬂuorescence intensity could be modulated by sequential oxidation of the TTF unit using chemical methods,which exhibited their potential application inﬂuorescence molecular switch.

关键词： tetrathiafulvalene tetraphenylporphyrin dyad triad ﬂuorescence molecular switch

巨噬细胞迁移抑制因子调节登革病毒2型感染诱导人脐静脉内皮细胞自噬的研究

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中华微生物学和免疫学杂志 2022年第3期42卷 185-193页

作者：苟小琴吴宁左丽贵州医科大学基础医学院免疫学教研室贵阳550000

目的:研究原代人脐静脉内皮细胞(primary human umbilical vein endothelial cells,HUVEC)被登革病毒2型(dengue virus type 2,DENV2)感染后,巨噬细胞迁移抑制因子(macrophage migration inhibitory factor,MIF)对腺苷酸激活蛋白激酶(adenosine 5′-monophosphate-activated protein kinase,AMPK)/细胞外调节蛋白激酶(extracellular regulated protein kinases,ERK)/雷帕霉素靶蛋白(mammalian target of rapamycin,mTOR)自噬信号途径的影响。方法:TCID 50检测DENV2对C6/36细胞的毒力,RT-PCR检测DENV2感染后HUVEC内病毒NS1基因部分片段;透射电子显微镜观察自噬体结构,Western blot检测不同剂量病毒感染HUVEC后对微管关联蛋白Ⅱ(microtubule-associated proteinsⅡ,LC3-Ⅱ)表达的影响和不同时间MIF的蛋白质水平变化,分析MIF与自噬相关蛋白LC3-Ⅱ的相关性;MIF抑制剂和通路抑制剂分别预处理DENV2感染的HUVEC,Western blot检测MIF、AMPK、ERK、mTOR和LC3-Ⅱ蛋白变化,分析MIF与AMPK自噬通路的关联。结果:实验用毒株对C6/36细胞的TCID 50为10-9.09/ml,被感染的HUVEC内可检测病毒NS1基因部分片段序列。不同剂量病毒感染后,在HUVEC内可形成自噬小体或自噬溶酶体,自噬水平有差异。DENV2感染HUVEC引起MIF和LC3-ⅡmRNA水平的变化呈正相关,MIF抑制剂的处理影响通路蛋白AMPK、ERK和LC3-Ⅱ的表达,但几乎不影响MIF的蛋白质水平。结论:DENV2感染HUVEC引起的MIF变化可影响自噬水平,MIF通过调控AMPK/ERK/mTOR途径影响自噬。

关键词：登革病毒2型巨噬细胞迁移抑制因子自噬腺苷酸激活蛋白激酶原代人脐静脉内皮细胞

Inverse hydrogen bonds between SiH_4 and hydrides of Na,Mg and Be

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Science China Chemistry 2011年第1期54卷 186-193页

作者： YUAN Kun zuo GuoFang LIU YanZhi ZHU YuanCheng LIU XinWen ZHANG JunYan Key Laboratory for New Molecule Design and Function of Gansu Education Department College of Life-Science and Chemistry Tianshui Normal University Tianshui 741001 China State Key Laboratory of Solid Lubrication Lanzhou Institute of Chemical Physics Chinese Academy of Sciences Lanzhou 730000 China

The optimized geometries of the three complexes between MeHn (Me=Na,Mg,Be;n=1 or 2) and SiH4 have been calculated at the B3LYP/6-311++g**,MP2/6-311++g(3df,3pd) and MP2/aug-cc-pvtz levels,*** red-shift inverse hydrogen bonds (IHBs) based on Si-H,an electron donor,were *** calculated binding energies with basis set super-position error (BSSE) correction of the three complexes are-5.98,-8.65 and-3.96 kJ mol-1 (MP2/6-311++g(3df,3pd)),respectively,which agree with the results obtained via MP2/aug-cc-pvtz (-6.18,-9.12 and-4.28 kJ mol-1,respectively).The relative stabilities of the three complexes are in the order of SiH4···MgH2 > SiH4···NaH > SiH4···*** bond orbital theory (NBO) analysis and the chemical shift calculation of the related atoms revealed that the charges flow from SiH4 to MeHn and the chemical shifts of the interacting H shift to ***,the Si1-H3 of SiH4 acts as both a bond hydrogen donor and an electron ***,compared with conventional hydrogen bonds,they formed IHB *** in molecules (AIM) theory have been used to investigate the topological properties of the critical points in the three IHB structures.

关键词： SiH4 氢化钠氢键氢化物优化几何构型镁电子供体相对稳定性

Liver injury associated with acute pancreatitis:The current status of clinical evaluation and involved mechanisms

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World Journal of Clinical Cases 2021年第34期9卷 10418-10429页

作者： Wei Liu Juan-Juan Du Zeng-Hui Li Xin-Yu Zhang Hou-Dong zuo Sichuan Key Laboratory of Medical Imaging Department of RadiologyThe Affiliated Hospital of North Sichuan Medical CollegeNanchong 637000Sichuan ProvinceChina

Acute pancreatitis(AP)is a very common acute disease,and the mortality rate of severe AP(SAP)is between 15%and 35%.The main causes of death are multiple organ dysfunction syndrome and *** mortality rate of patients with SAP related to liver failure is as high as 83%,and approximately 5%of the SAP patients have fulminant liver *** function is closely related to the progression and prognosis of *** this review,we aim to elaborate on the clinical manifestations and mechanism of liver injury in patients with AP.

关键词： Acute pancreatitis Liver injury Liver dysfunction Cytokines Oxidative stress

带约束拉杆十字形钢管混凝土短柱轴压试验研究

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建筑钢结构进展 2022年第7期24卷 38-48页

作者：赵小芹左志亮蔡健广州城市理工学院土木工程学院广州510800 华南理工大学土木与交通学院广州510641 华南理工大学亚热带建筑科学国家重点实验室广州510641

进行了11个带约束拉杆和5个不带约束拉杆十字形钢管混凝土短柱试件的轴压试验研究,讨论在不同约束拉杆间距与直径、钢板厚度与屈服强度以及截面尺寸下十字形钢管混凝土短柱的破坏特点、承载力、延性、拉杆与钢管的应变发展特点等轴压性... 详细信息

进行了11个带约束拉杆和5个不带约束拉杆十字形钢管混凝土短柱试件的轴压试验研究,讨论在不同约束拉杆间距与直径、钢板厚度与屈服强度以及截面尺寸下十字形钢管混凝土短柱的破坏特点、承载力、延性、拉杆与钢管的应变发展特点等轴压性能。结果表明,约束拉杆的设置改变了钢管的屈曲模态,延缓了钢管局部屈曲的发生,限制了阴角处钢管的外鼓变形,使钢板的纵、横向应变分布更为均匀,保证了钢管纵向承载力的发挥,提高了核心混凝土的约束效应,有助于提高十字形钢管混凝土轴压短柱的承载力和延性;减小拉杆间距、增大板厚、增大拉杆直径时,拉杆约束钢管外鼓变形的作用增大。采用现行规程中的矩(方)形钢管混凝土柱轴压承载力计算公式对试件峰值荷载进行估算,结果表明只有当钢板相对宽厚比小于22时,不带拉杆试件的承载力才能按叠加材料强度的EC4公式估算;带拉杆试件的承载力至少可按材料强度叠加法估算,拉杆间距较小或钢板厚度较大时可近似用GJB 4142—2000和DBJ 13-51—2003公式估算。最后,考虑钢管和拉杆的约束效应以及不带拉杆钢管纵向承载力低的情况,提出了十字形钢管混凝土柱轴压承载力计算公式,计算值与试验值吻合良好。

关键词：十字形钢管混凝土短柱约束拉杆轴压试验极限承载力

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艺术,如何与时间“在一起”?

北京电影学院学报 2022年第1期 60-70页

作者：左官春刘魁东南大学马克思主义学院

近年来,时间问题成为艺术学理论发展的重要议题。艺术时间具有永恒之美的绵延属性,但却纠缠于艺术史时代发展主题当中,其根源在于艺术史就是一部哲学遮蔽时间在场性的存在遗忘史。关乎艺术本源的线性时间规定弃绝了艺术时间的存在性,因... 详细信息

近年来,时间问题成为艺术学理论发展的重要议题。艺术时间具有永恒之美的绵延属性,但却纠缠于艺术史时代发展主题当中,其根源在于艺术史就是一部哲学遮蔽时间在场性的存在遗忘史。关乎艺术本源的线性时间规定弃绝了艺术时间的存在性,因而澄明艺术时间在场性的"在一起"从未在艺术文本中显现。为此,艺术时间需要从哲学分析范式中退场,回到艺思同源的在的场域,从而实现艺术与时间的在场性同一。

关键词：艺术时间图像印象当代性 “在一起”

Optical sampling system using periodically-poled lithium niobate waveguide and nonlinear polarization rotation mode-locked fiber laser

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Frontiers of Optoelectronics 2012年第2期5卷 208-213页

作者： Jian LI Aiying YANG Lin zuo Junsen LAI Yunan SUN School of Optoelectronics Beijing Institute of TechnologyBeijing 100081China

A novel design of optical sampling system has been developed by using sum-frequency generation （SFG） in a periodically-poled lithium niobate （PPLN） waveguide and using passive mode-locked fiber laser pulses as optical sampling pulses. The system achieved high temporal resolution and high sensitivity using a 30 mm length PPLN with quasi phase match period of 19.3 μm and 151 fs sampling pulses which were generated by passive modelock fiber laser based on nonlinear polarization rotation （NPR）. Clear eye-diagram of 10 Gbit/s non-return-to-zeros （NRZ） pseudorandom binary sequence （PRBS） optical signal were successfully reconstructed by this system.

关键词： periodically-poled lithium niobate (PPLN),optical sampling nonlinear polarization rotation (NPR)fiber laser sum-fi'equency generation (SFG)