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“一带一路”倡议下的行业出口质量升级

南开经济研究 2024年第5期 67-86页

作者：司志宾秦凤鸣程敏山东大学经济学院 250100 南开大学经济学院 :300071

本文基于BACI数据库HS6分位层面的贸易数据,测度了2010—2016年中国对214个国家和地区的行业出口质量,并利用双重差分模型识别了“一带一路”倡议对行业出口质量的影响。统计和实证结果都表明,“一带一路”倡议的实施可以显著提高行业... 详细信息

本文基于BACI数据库HS6分位层面的贸易数据,测度了2010—2016年中国对214个国家和地区的行业出口质量,并利用双重差分模型识别了“一带一路”倡议对行业出口质量的影响。统计和实证结果都表明,“一带一路”倡议的实施可以显著提高行业出口质量,该结果通过了各项稳健性检验。在此基础上,进一步探讨了倡议影响出口质量的潜在作用路径,发现倡议通过促进“出口竞争效应”和“OFDI逆向溢出效应”,最终使得行业出口质量整体上得到提高。另外,异质性分析表明,倡议对“一路”国家、较不发达国家以及低技术、价格竞争行业、优先发展行业具有更明显的“提质”效应。结构分解发现,行业出口质量的提高主要是由产品内效应和低质量产品的退出实现的。在此基础上,本文引入离散时间的生存分析模型,发现“一带一路”倡议提高了产品退出出口市场的风险率,从而减少了其出口持续时间,验证了质量分解的结果;但同时可以通过提高产品质量来减少其退出市场的风险,有助于延长出口持续时间。综合来看,“一带一路”倡议发挥了“优胜劣汰”的作用。本文的研究为理解“一带一路”倡议在促进贸易平衡与可持续发展等方面的作用提供了新的视角与解释。

关键词： “一带一路”倡议行业出口质量结构分解生存分析

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Effect of Multi-pass Compression on the Microstructure of 7 085 Aluminum Alloy

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Journal of Wuhan University of Technology(Materials Science) 2022年第6期37卷 1240-1245页

作者：赵晓东 ZHANG Qizhu 李亚杰 qin fengming YANG Xiaohui CHU Zhibing School of Materials Science and Engineering Taiyuan University of Science and TechnologyTaiyuan 030024China

The isothermal compression tests of 7085 aluminum alloy were carried out on Gleeble-3800 thermal simulator by two-pass(30%per-pass)and three-pass(20%per-pass)at 300-400℃and the strain rate of 0.01 s^(-1).The effect of compression strategy on microstructure evolution of 7085 aluminum alloy was analyzed by optical microscopy(OM)and electron backscattering diffraction(EBSD).The results show the softening mechanism of 7085 aluminum alloy is mainly recovery,the recrystallization degree is sluggish when the samples deform at 300℃.The fraction of recrystallized grains just reaches 23.2%at a higher deformation temperature of 400℃,while a large amount of sub-grains with equiaxed morphology are formed inside the deformed *** deformation paths have a significant effect on the microstructure evolution of the 7085 aluminum alloys,and more uniform and fine microstructures are obtained at the three-pass *** addition,a short holding time of 5 s is not enough to trigger the static *** the holding time reaches 120 s,the dislocations rearrange and a large number of recrystallized grains and regular sub-grains appear inside the original *** a word,more uniform and fine microstructures are obtained at three-pass deformation at 400℃and 120 s of 7085 aluminum alloy.

关键词： 7085 aluminum alloy multi-pass hot deformation microstructure evolution recrystallization

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柳钢正火高强度船板EH36的研制开发

河南冶金 2024年第1期32卷 8-11,43页

作者：吴明哲王立群林木覃凤鸣柳州钢铁股份有限公司广西柳州545000

通过采用合理的成分体系、Nb+V+Ti微合金化设计,严格二阶段控制轧制,合理的正火工艺制度,实现了正火高强高韧低温系列产品的开发,扩展了柳钢船板品种系列,为沿海防城港基地3800 mm中厚板机组的产品开发提供了设计依据。

关键词：高强度船板 EH36 控制轧制正火低温韧性

Impact of Foreign Bank Presence on Foreign Direct Investment in China

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China & World Economy 2015年第4期23卷 40-59页

作者： Steven Ongena Shusen Qi fengming qin Department of Banking and Finance University of Zurich Zurich Switzerland Department of Finance Maastricht University Maastricht the Netherlands Department of Finance School of Economics Shandong University Jinan China

We analyze the impact of foreign bank presence on foreign direct investment （FDI） in China. The connection between the two couM be particularly relevant for an emerging economy like China because the supply of financial services provided by banks may act as a constraining factor. Foreign bankpresence may then enable and foster FDI and not simply result from it. Our estimates demonstrate that FDI across regions in China is increasing in the existing network of regional branches of foreign banks, which itself is driven （and, therefore, instrumented） by the timing of the regional phasing out of the local limits for foreign banks on local currency business. The effect of foreign bank presence on FDI is particularly strong for some specific sectors （farming, manufacturing, construction, transportation, wholesale/ retail trade and real estate） if those sectors are strongly represented in the source economies.

关键词： China foreign bank presence foreign direct investment

Hot Deformation Behavior and Processing Maps of As-cast Mn18Cr18N Steel

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Journal of Wuhan University of Technology(Materials Science) 2017年第4期32卷 935-943页

作者：陈慧琴 wang zhenxing qin fengming jia peijie zhao xiaodong School of Materials Science and Engineering Taiyuan Universityof Science and Technology Taiyuan 030024China

Hot deformation behavior of as-cast Mn18Cr18 N austenitic stainless steel was studied in the temperature range of 950-1200 ℃ and strain rate range of 0.001-1 s^（-1） using isothermal hot compression tests. The true stress-strain curves of the steel were characterized by hardening and subsequent softening and varied with temperatures and strain rates. The hot deformation activation energy of the steel was calculated to be 657.4 k J/mol, which was higher than that of the corresponding wrought steel due to its as-cast coarse columnar grains and heterogeneous structure. Hot processing maps were developed at different plastic strains, which exhibited two domains with peak power dissipation efficiencies at 1150 ℃/0.001 s^（-1） and 1200 ℃/1 s^（-1）, respectively. The corresponding microstructures were analyzed by optical microscopy（OM）, scanning electron microscopy（SEM）, and electron backscatter diffraction（EBSD）. It has been confirmed that dynamic recrystallization（DRX） controlled by dislocation slipping and climbing mechanism occurs in the temperature and strain rate range of 1050-1200 ℃ and 0.001-0.01 s^（-1）; And DRX controlled by twinning mechanism occurs in the temperature and strain rate range of 1100-1200 ℃, 0.1-1 s^（-1）. These two DRX domains can serve as the hot working windows of the as-cast steel at lower strain rates and at higher strain rates, respectively. The processing maps at different strains also exhibit that the instability region decreases with increasing strain. The corresponding microstructures and the less tensile ductility in the instability region imply that the flow instability is attributed to flow localization accelerated by a few layers of very fine recrystallized grains along the original grain boundaries.

关键词： Mn18Cr18N steel hot deformation hot processing map dynamic recrystallization hot workability

MoS_(2) nanoflowers and PEDOT:PSS nanocomposite enabling wearable dual-mode pressure sensors

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Science China(Technological Sciences) 2024年第6期67卷 1737-1747页

作者： WANG fengming YANG WeiJia MA Ke SHEN GengZhe SU DaoJian LI BaiJun WANG ShuangPeng qin BoLong ZHANG Chi XIN Yue CAO XiaoBing HE Xin School of Applied Physics and Materials Wuyi UniversityJiangmen529020China Biomaterials R&D Center Zhuhai Institute of Advanced TechnologyChinese Academy of SciencesZhuhai519003China Joint Key Laboratory of the Ministry of Education Institute of Applied Physics and Materials EngineeringUniversity of MacaoMacao999078China

A versatile sensing platform employing inorganic MoS_(2) nanoflowers and organic poly(3,4-ethylene dioxythiophene):poly(styrene sulfonate)(PEDOT:PSS)has been investigated to develop the resistive and capacitive force-sensitive *** microstructure of the sensing layer heightens the sensitivity and response time of the dual-mode pressure sensors by augmenting electron pathways and inner stress in response to mechanical ***,the capacitive and resistive sensors exhibit sensitivities of 0.37 and 0.12 kPa^(-1),respectively,while demonstrating a remarkable response time of approximately 100 ***,it is noteworthy that the PEDOT:PSS layer exhibits excellent adhesion to polydimethylsiloxane(PDMS)substrates,which contributes to the development of highly robust force-sensitive sensors capable of enduring more than 10000loading/unloading *** combination of MoS_(2)/PEDOT:PSS layers in these dual-mode sensors has shown promising results in detecting human joint movements and subtle physiological ***,the sensors have achieved a remarkable precision rate of 98%in identifying target *** outcomes underscore the significant potential of these sensors for integration into applications such as electronic skin and human-machine interaction.

关键词： MoS_(2)/PEDOT:PSS nanocomposite force-sensitive sensor multi-scaled microstructure physiological signals monitoring object grasping recognition

Influence of Annealing Treatment on Microstructure Evolution and Mechanical Property of Friction Stir Weld AZ31 Mg Alloys

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Journal of Wuhan University of Technology(Materials Science) 2019年第2期34卷 417-425页

作者：李亚杰 qin fengming LIU Cuirong LI Leijun ZHAO Xiaodong 吴志生 School of Materials Science and Engineering Taiyuan University of Science and Technology Department of Chemical and Materials Engineering University of Alberta

In order to improve microstructure distribution and mechanical properties of Mg alloy joint by annealing treatment, die-casting AZ31 Mg alloy was successfully welded at rotation speed of 1 400 rpm and travel speed of 200 mm/min. The welded joints were annealed at 150-300 ℃ for 15-120 min and then were subjected to transverse tensile. The microstructure of annealed joints was analyzed by optical microscopy and electron backscatter diffraction. The experimental results indicate that(0001) texture intensity in stir zone significantly reduces and sharp transition of grain size is relieved in the interface between stir zone and thermo-mechanically affected zone after annealed at 200 ℃ for 30 min. Meanwhile, the elongation is increased from 7.5% to 13.0% and strength is increased slightly. It is because that annealing treatment can inhibit twin transformation and retain its ability to coordinate deformation during tensile deformation, which contributes to the improvement of plasticity. In addition, annealing treatment can increase the width of interfacial transition zone and lead to gradual transition of grain size between the SZ and TMAZ, which balances dislocation diffusion rate in different zone.

关键词： magnesium alloys friction stir welding annealing treatment texture distribution plasticity

Has Minority Foreign Investment in China's Banks Improved Their Cost Efficiency?

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China & World Economy 2008年第3期16卷 57-74页

作者： James Laurenceson fengming qin School of Economics University of Queensland Brisbane Australia School of Economics Shandong University Shandong China

Since 2001, foreign investors have been permitted to acquire minority ownership stakes m China＇s banks. This paper assesses whether there is any evidence of a cost efficiency payoff m those banks that have taken on foreign investment. Data envelopment analysis isfirst used to generate measures of cost efficiency for China＇s banks over the period 2001-2006. A second stage regression is then performed to determine whether foreign investment has an impact on cost efficiency. The results indicate a positive relationship, although one that is not statistically significant. Policy implications are discussed.

关键词： banking cost efficiency foreign investment

SAF2205双相不锈钢多层多道焊接头的组织及性能

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焊接学报 2023年第6期44卷 74-81,I0007,I0008页

作者：李亚杰刘瑞秦凤明马承睿太原科技大学太原030024

采用TIG/PAW复合焊接对SAF2205双相不锈钢进行多层多道焊接,并进行固溶处理,利用OM、SEM、EBSD等设备,通过电化学腐蚀、拉伸、冲击等试验研究焊缝组织演变与综合性能的关系.结果表明:TIG填丝盖面焊接处的焊缝铁素体含量为70.5%,由于添... 详细信息

采用TIG/PAW复合焊接对SAF2205双相不锈钢进行多层多道焊接,并进行固溶处理,利用OM、SEM、EBSD等设备,通过电化学腐蚀、拉伸、冲击等试验研究焊缝组织演变与综合性能的关系.结果表明:TIG填丝盖面焊接处的焊缝铁素体含量为70.5%,由于添加焊丝的原因,焊缝奥氏体晶粒最大为177μm^(2),大于母材142μm^(2);PAW焊缝铁素体含量为65.4%,因为焊接顺序的不同,后续焊接对焊缝有加热作用,导致铁素体含量最少;在TIG焊缝中,热输入较大,导致铁素体晶粒粗化最大为8147μm^(2),大于母材264μm^(2),导致奥氏体形核位置减少,奥氏体仅为3.96%.在1050℃固溶处理60 min后焊缝两相接近1∶1,并且奥氏体趋于均匀化,随固溶时间的延长耐腐蚀性增强.焊态焊缝抗拉强度大于846 MPa,拉伸断裂均在母材.焊缝冲击吸收能量为144 J,小于母材(156 J),焊缝表现为复合断裂.

关键词： SAF2205双相不锈钢复合焊接TIG/PAW 微观组织固溶处理综合性能