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Microstructure and kinetics of hot deformation WE43 magnesium alloy

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Rare Metals 2008年第4期27卷 405-409页

作者： GAO Jiacheng wang Qiang wang yong li Wei NIU Wenjuan College of Materials Science and Engineering National Engineering Research Center for Magnesium Alloys Chongqing University Chongqing 400044 China

The effect of compression on the microstructures and flow behavior of WE43 magnesium alloy was investigated in this article. The relationship between flow stress and strain rate was discussed. According to the empirical formula ε = Aδ^n exp （-Q/R T）, the value of heat activation of WE43 magnesium alloys is 297,15 kJ/mol. A mechanism of deformation softening of WE43 alloy in testing hot deformation was identified to be dynamic recrystallization.

关键词： WE43 magnesium alloy hot deformation microstructure kinetics

High temperature corrosion behavior of arc-sprayed aluminum coatings on steel

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中国有色金属学会会刊：英文版 2004年第z1期14卷 451-454页

作者： SUN Jian-bo wang yong DONG li-xian College of Mechanical and Electronic Engineering University of Petroleum Dongying 257061 China College of Mechanical and Electronic Engineering University of Petroleum Dongying 257061 China College of Mechanical and Electronic Engineering University of Petroleum Dongying 257061 China

Aluminum coatings were sprayed on the substrate of steel Q235 by arc spraying. The test samples of Q235, Al coatings and Al coatings with seal coat were placed in box type electric resistance furnace at 400, 500,600, 650 ℃ when their oxidation behaviors were studied. And their oxidation kinetics curves were protracted. Microstructure, microhardness, bond strength and distribution of section elements were investigated by optical microscope(OM), Vickers microhardness instrument, electric tensile test machine and EPMA. Al coatings and Al coatings with seal coat can enhance the oxidation-resistance of substrate under 500 ℃. The latter has the best corrosion resistance. The coatings can't protect the substrate against oxidation above 600 ℃. After a long time corrosion there is enriched oxygen element at interface.

关键词： arc spraying Al coating Al coating with seal coat high temperature corrosion oxidation kineticscurve

数字经济与碳排放强度：来自“一带一路”国家的经验证据

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广西师范大学学报(哲学社会科学版) 2025年第1期061卷 115-127页

作者：王立勇许娇冯涵一中央财经大学国际经济与贸易学院俄亥俄州立大学

数字经济依托互联网、云计算等高新技术，已成为引领社会变革的推动力，数字经济的蓬勃发展成为驱动经济增长新引擎。基于“一带一路”沿线47个国家的面板数据，分析数字经济对碳排放强度的影响及其内在机制，并分析数字经济碳减排的空... 详细信息

数字经济依托互联网、云计算等高新技术，已成为引领社会变革的推动力，数字经济的蓬勃发展成为驱动经济增长新引擎。基于“一带一路”沿线47个国家的面板数据，分析数字经济对碳排放强度的影响及其内在机制，并分析数字经济碳减排的空间溢出效应，研究结果表明：数字经济发展对碳排放强度具有显著的负向影响，即随着一国数字经济发展水平的提高，其碳排放强度倾向于降低；数字经济发展水平的提高会通过“技术创新效应”“贸易规模效应”和“贸易结构效应”对一国碳排放强度产生影响；本国数字经济发展对周边国家碳排放强度具有显著的抑制作用，即一国数字经济水平的提高具有空间溢出效应。我国应持续推进数字经济高质量发展，深入挖掘数字贸易发展新动能，并搭建数字化平台，积极推动碳减排技术的国际合作。

关键词：数字经济碳排放强度一带一路贸易机制

Synthesis, Crystal Structure and Insecticidal Activities of Novel Neonicotinoid Derivatives

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Chemical Research in Chinese Universities 2010年第3期26卷 380-383页

作者： ZHAO Yu wang Gang li yong-qiang wang Su-hua li Zheng-ming State Key Laboratory of Elemento-Organic Chemistry Research Institute of Elemento-Organic Chemistry National Pesticide Engineering Research Center（Tianjin） Nankai University Tianjin 300071 P. R. China

Ten new N-oxalyl derivatives of neonicotinoid compound were designed and synthesized. Their structures were confirmed by ^1H NMR spectra, elemental analysis and X-ray diffraction. The preliminary insecticidal activities of the new compounds were evaluated. The results of bioassays indicate that the title Compounds exhibit moderate insecticidal activities. Surprisingly, the insecticidal activity of compound 7b against bean aphids at 200 mg/kg is 100%, which is comoarable to that of the commercialized imidacloprid.

关键词： Neonicotinoid N-Oxalyl derivative Insecticidal activity Bean aphid Imidacloprid

Molecular design,synthesis and biological activities of amidines as new ketol-acid reductoisomerase inhibitors

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Chinese Chemical Letters 2008年第6期19卷 651-654页

作者： Bao Lei wang yong Hong li Jian Guo wang Yi Ma Zheng Ming li Elemento-Organic Chemistry Institute State-Key Laboratory of Elemento-Organic Chemistry Nankai University Tianjin 300071 China

Diamidine （A） was identified in our in vitro bio-assay as a possible inhibitor of ketol-acid reductoisomerase （KARI） from the ACD database search based on the known three-dimensional crystal structure of KARI. An investigation on interaction of A on KARI active sites, led to the design and synthesis of 15 novel monoamidines. Some of those showed better biological activity than A on rice KARI （in vitro） and in greenhouse herbicidal tests （in vivo）. The structure-biological activity relationship was investigated, which provides valuable information to further study of potential KARI inhibitors.

关键词： KARl Molecular design Synthesis Biological activity

A Possible Experimental Test on Five-Dimensional Gravitation Theory of Complex Field

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Communications in Theoretical Physics 2008年第2期49卷 382-384页

作者： wang yong-Jiu li Ai-Gen TANG Zhi-Ming Institute of Physics Hunan Normal University Changsha 410081 China

By appropriately choosing additional dimensions of space-time, the mass spectrum of mesons is obtained, and the calculated results agree with the experimental data.

关键词： gravitation complex field experiment inspect

Solidification microstructure of high borated stainless steels with rare earth and titanium additions

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Rare Metals 2020年第12期39卷 1483-1491页

作者： yong-wang li Hai-Tao liu Zhao-Jie wang Zhi-Heng Zhang Wei-Ting li Hui-Ying Shen Xiao-Ming Zhang Guo-Dong wang State Key Laboratory of Rolling and Automation Northeastern UniversityShenyang 110819China

To study the effects of rare earth(RE)and Ti on the solidification micros true ture of high borated stainless steels,1.6 wt%B stainless steel doped with RE and2.1 wt%B stainless steel doped with Ti were prepared by ingot casting,*** solidification microstructure of researched steels was characterized in *** modification mechanism was clarified based on the heterogeneous nucleation theory and the thermodynamic *** solidification microstructure of 1.6 wt%B and 2.1 wt%B stainless steels was characterized by the continuous and network-like eutectic borides around the matrix *** was found that the fine RE compounds could act as the heterogeneous nuclei for both borides and austenite during ***,the eutectic borides were more dispersed in the modified ***,lots of fine‘eutectic cells’were formed in the matrix *** a result of the preferential formation of TiB2 during solidification,the amount of the eutectic borides in the steel modified with Ti was significantly ***,the continuity of the eutectic borides network was *** a word,the present work provides a promising method to modify the solidification microstructure for high borated stainless steels.

关键词： Borated stainless steels Solidification microstructure Rare earth Titanium

Studies on vibration characteristics of a pear using finite element method

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Journal of Zhejiang University-Science B(Biomedicine & Biotechnology) 2006年第6期7卷 491-496页

作者： SONG Hui-zhi wang Jun li yong-hui Department of Biosystems Engineering Zhejiang University Hangzhou 310029 China

The variation of the vibration characteristics of a Huanghua pear was investigated using finite element simulations. A new image processing technique was used to obtain the unsymmetrical and un-spherical geometrical model of a pear. The vibra-tion characteristics of this type of pear with the correlation of its behavior with geometrical configurations and material charac-teristics were investigated using numerical modal analysis. The results showed that the eigenfrequency increased with the in-creasing pear Young’s modulus, while decreased with increasing pear density, and decreased with increasing pear volume. The results of this study provided foundation for further investigations of the physical characteristics of fruits and vegetables by using finite element simulations.

关键词： Pear Vibration characteristics Unsymmetrical and un-spherical model Finite element analysis

Soil organic carbon contents, aggregate stability,and humic acid composition in different alpine grasslands in Qinghai-Tibet Plateau

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Journal of Mountain Science 2016年第11期13卷 2015-2027页

作者： CAO Zhi-yuan wang yong li Jie ZHANG Jin-jing HE Nian-peng Key Laboratory of Ecosystem Network Observation and Modeling Institute of Geographic Sciences and Natural Resources Research Chinese Academy of Sciences Beijing 100101 China

Alpine grassland soils on Qinghai-Tibet Plateau store approximately 33.5 Pg of organic carbon(C) at 0–0.75 m depth and play an important role in the global carbon *** investigated soil organic C(SOC),water-soluble organic C(WSOC),easily oxidizable organic C(EOC),humic C fractions,aggregate-associated C,aggregate stability,and humic acid(HA) composition along an east-west transect across Qinghai-Tibet Plateau,and explored their spatial patterns and controlling *** contents of SOC,WSOC,EOC,humic C fractions and aggregate-associated C,the proportions of macroaggregates(2-0.25) and micro-aggregates(0.25-0.053 mm),and the aggregate stability indices all increased in the order alpine desert liphatic C/aromatic C ratio of HA increased as alpine desert lity indices along this *** all these C fractions,SOC content and aggregate stability were more closely associated with humic C and silt and clay sized C in comparison with WSOC,EOC,and macro- and microaggregate *** results suggested that alpine meadow soils containing higher SOC exhibited high soil aggregation and aggregate *** annual precipitation should be the main climate factor controlling the spatial patterns of SOC,soil aggregation,and aggregate stability in this *** resistant and stable C fractions rather than labile C fractions are the major determinant of SOC stocks and aggregate stability.

关键词： Soil organic carbon Aggregate stability Humic acid Carbon-13 nuclear magnetic resonance Latitudinal transect Qinghai-Tibet Plateau