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Synthesis, insecticidal activities and DFT study of pyrimidin-4-amine derivatives containing the 1,2,4-oxadiazole motif

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Frontiers of Chemical Science and Engineering 2022年第7期16卷 1090-1100页

作者： yong-Hui wen Long Cheng Tian-Ming Xu Xing-Hai Liu Ning-Jie Wu College of Chemical Engineering Zhejiang University of TechnologyHangzhou 310014China Zhejiang Base of National Southern Pesticide Research Centre Zhejiang Research Institute of Chemical IndustryHangzhou 310023China

Twenty six novel pyrimidin-4-amine derivatives containing the 1,2,4-oxadiazole motif were synthesized. Their chemical structures were confirmed by ^(1)H nuclear magnetic resonance (NMR), ^(13)C NMR, and high-resolution mass spectrography. The insecticidal activity results indicated that some of them possessed excellent insecticidal activity (100%) against Mythimna separate, especially for compounds 6d, 6f, 6o, 6w, 6y and 6z. These compounds exhibited no activity against the insects Aphis medicagini and Tetranychus cinnabarinus. The structure- insecticidal activity relationships are discussed. Density functional theory analysis can potentially be used to design more active compounds. These results provide useful insecticide design information for further optimization.

关键词： synthesis pyrimidin-4-amine derivatives 1,2,4-oxadiazole insecticidal activity structure-activity relationship

基于集聚度和Arcgis的江苏省卫生资源配置差异性研究

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现代医院管理 2024年第3期22卷 1-4页

作者：李瑞雪温勇舒星宇南京邮电大学理学院南京市210046 南京邮电大学社会与人口学院南京市210046

目的通过研究江苏省卫生资源配置的区域差异性,为合理优化资源配置,更快更好地推动“健康江苏”建设提供参考依据。方法采用描述统计分析法、集聚度法和Arcgis空间插值法对2010年和2020年江苏省各市卫生资源配置情况进行对比分析。结果... 详细信息

目的通过研究江苏省卫生资源配置的区域差异性,为合理优化资源配置,更快更好地推动“健康江苏”建设提供参考依据。方法采用描述统计分析法、集聚度法和Arcgis空间插值法对2010年和2020年江苏省各市卫生资源配置情况进行对比分析。结果十年间江苏省苏南、苏中和苏北地区卫生资源集聚度相差较大,存在不公平现象。苏南地区的卫生资源相对充足,基本满足居民对医疗服务的需求;苏中和苏北地区卫生资源虽然在地理配置与人口配置的公平性上有较大改善,但仍不及苏南地区。结论江苏省卫生资源配置存在明显的地区差异,苏南地区优于苏中、苏北地区。政府应发挥主导作用,优化资源空间布局,缩小区域间差异。

关键词：卫生资源配置集聚度 Arcgis空间插值江苏省

Study of Friction between Liquid Crystals and Crystalline Surfaces by Molecular Dynamic Simulations

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Communications in Theoretical Physics 2016年第10期65卷 467-473页

作者： yong-wen Zhang Xiao-Song Chen Wei Chen CAS Key Laboratory of Theoretical Physics Institute of Theoretical Physics Chinese Academy of Sciences P.O. Box 2735 Beijing 100190 China School of Physical Sciences University of Chinese Academy of Sciences Beijing 100049 China Computer Network Information Center Chinese Academy of Sciences P.O. Box 349 Beijing 100190 China

The lubrication characteristics of liquid crystal(LC) molecules sheared between two crystalline surfaces obtained from molecular dynamics(MD) simulations are reported in this *** consider a coarse-grained rigid bead-necklace model of the LC molecules confined between two atomic surfaces subject to different shearing velocities.A systematic study shows that the slip length of LC lubrication changes significantly as a function of the LC-surface interaction energy,which can be well described though a theoretical *** slip length increases as shear rate increases at high LC-surface interaction ***,this trend can not be observed for low interaction *** orientation of the LC molecules near the surface is found to be guided by the atomics *** influence of temperature on the lubrication characteristics is also discussed in this article.

关键词： liquid crystal friction slip length molecular dynamics simulation

Improving the Mechanical and Tribological Properties of NiTi Alloys by Combining Cryo-Rolling and Post-Annealing

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Acta Metallurgica Sinica(English Letters) 2022年第2期35卷 317-325页

作者： yong wen Yan-Fei Wang Hao Ran Wei Wei Jun-Ming Zhang Chong-Xiang Huang School of Aeronautics and Astronautics Sichuan UniversityChengdu 610065China

By combining cryo-rolling and post-annealing treatments,the nanostructured NiTi alloy is produced.A diff erential scanning calorimetry measurement was used to test the eff ect of the preparation process on phase *** cryo-rolling changes the tensile fracture of NiTi alloy to a ductile ***,the recovered structure exhibits signifi cant strength improvement,while the tensile plasticity is still comparable to that of the coarse-grained *** optimized mechanical performance is due to the strengthening eff ect of refi ned microstructure and the high work hardening capability rendered by moderate dislocation ***-on-plate reciprocating dry-sliding wear test reveals that the nanostructured NiTi alloy also has enhanced wear resistance,which is primarily ascribed to the high content of residue martensite formed during *** results provide an eff ective route to optimize the mechanical and wear properties of NiTi alloys.

关键词： NiTi alloy Phase transformation Strength and ductility Wear resistance Cryogenic rolling

Extending Structures for Gel'fand-Dorfman Bialgebras

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Acta Mathematica Sinica,English Series 2024年第2期40卷 619-638页

作者： Jia Jia wen Yan yong HONG School of Mathematics Hangzhou Normal UniversityHangzhou 311121P.R.China

Gel'fand-Dorfman bialgebra,which is both a Lie algebra and a Novikov algebra with some compatibility condition,appeared in the study of Hamiltonian pairs in completely integrable *** also emerged in the description of a class special Lie conformal algebras called quadratic Lie conformal *** this paper,we investigate the extending structures problem for Gel'fand-Dorfman bialgebras,which is equivalent to some extending structures problem of quadratic Lie conformal ***,given a Gel'fand-Dorfman bialgebra(A,o,[.,.]),this problem is how to describe and classify all Gel'fand-Dorfman bialgebra structures on a vector space E(A⊂E)such that(A,o,[.,.])is a subalgebra of E up to an isomorphism whose restriction on A is the identity *** by the theories of extending structures for Lie algebras and Novikov algebras,we construct an object gH2(V,A)to answer the extending structures problem by introducing the notion of a unified product for Gel'fand-Dorfman bialgebras,where V is a complement of A in *** particular,we investigate the special case when dim(V)=1 in detail.

关键词： Gel'fand-Dorfman bialgebra Lie conformal algebra Extending structures problem Novikovalgebra

Hot deformation behavior and microstructural evolution of powder metallurgical TiAl alloy

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Rare Metals 2017年第4期36卷 236-241页

作者： Na Liu Zhou Li wen-yong Xu Yue Wang Guo-Qing Zhang Hua Yuan Science and Technology on Advanced High TemperatureStructural Materials Laboratory Beijing Institute of Aeronautical Materials Beijing 100095 China

The hot deformation behavior of powder met- allurgical （PM） TiAI alloys was investigated on Gleeble- 3500 thermomechanical simulator, at a temperature range of 1050-1200 ℃ with an interval of 50℃ and a strain rate range of 0.001-1.000 s-1. The results show that the flow stress of PM TiAI alloy is sensitive to deformation tem- perature and strain rate, the peak stress decreases with the increase in deformation temperature and decrease in strain rate, and dynamic recrystallization occurs during the hot compression. The deformation active energy was calcu- lated and the flow stress model during high-temperature deformation was established based on the Arrhenius equations and Zener-Hollomon parameter. The deformed microstructure consists of refined homogeneous γ and α2/γ grains.

关键词： TiAI alloy Powder metallurgy Hotdeformation Flow stress

Hydrogen induced cracking of X80 pipeline steel

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International Journal of Minerals,Metallurgy and Materials 2010年第5期17卷 579-586页

作者： Chao-fang Dong Kui Xiao Zhi-yong Liu wen-jing Yang Xiao-gang Li Corrosion and Protection Center University of Science and Technology Beijing Beijing 100083 China

The hydrogen-induced cracking （HIC） behavior of X80 pipeline steel was studied by means of electrochemical charging, hydrogen permeation tests, tension test, and scanning electron microscopy （SEM）. The experimental results indicate that the increase of charging time and charging current density or the decrease of the solution pH value leads to an increase of the hydrogen content in X80 steel, which plays a key role in the initiation and propagation of HIC. It is found that the majority of macro-inclusions within the as-used X80 steel do not constitute a direct threat to HIC except aluminum oxides, which directly or indirectly lead to HIC. The hydrogen trap density at room temperature is estimated to be pretty high, and this is an essential reason why the steel is sensitive to HIC. After hydrogen charging, the elongation loss rate and area reduction of X80 steel decline obviously, taking a noticeable sign of hydrogen-induced plasticity damages. It is demonstrated that the losses of these plastic parameters have a linear relation to the fracture size due to hydrogen.

关键词： pipeline steel hydrogen induced cracking electrochemical charging fracture

Theoretical Approximation of Focusing-Wave Induced Load upon A Large-Scale Vertical Cylinder

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China Ocean Engineering 2017年第5期31卷 598-606页

作者： XUE Hong-xiang HU Zhe TANG wen-yong ZHANG Xiao-ying WANG Kun-peng State Key Laboratory of Ocean Engineering Shanghai Jiao Tong University Collaborative Innovation Center for Advanced Ship and Deep-Sea Exploration Key Laboratory of Ships and Ocean Engineering of Fujian Province Jimei University School of Naval Architecture and Ocean Engineering Jiangsu University of Science and Technology

Until now, most researches into the rogue-wave-structure interaction have relied on experimental measurement and numerical simulation. Owing to the complexity of the physical mechanism of rogue waves, theoretical study on the wave-structure issue still makes little progress. In this paper, the rogue wave flow around a vertical cylinder is analytically studied within the scope of the potential theory. The rogue wave is modeled by the Gauss envelope, which is one particular case of the well-known focusing theory. The formulae of the wave-induced horizontal force and bending moment are proposed. For the convenience of engineering application, the derived formulae are simplified appropriately, and verified against numerical results. In addition, the influence of wave parameters, such as the energy focusing degree and the wave focusing position, is thoroughly investigated.

关键词： rogue wave Gauss envelope upright cylinder potential theory analytical approximation

Stability and Collective Excitation of Two-Dimensional BECs with Two-and Three-Body Interactions in an Anharmonic Trap

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Communications in Theoretical Physics 2009年第3期51卷 433-440页

作者： yong wen-Mei WEI Xiu-Fang ZHOU Xiao-Yan XUE Ju-Kui College of Physics and Electronics Engineering Northwest Normal University Lanzhou 730070 China College of Science Gansu Agricultural University Lanzhou 730070 China Department of Physics Lanzhou City University Lanzhou 730070 China

The stability and collective excitation of Bose-Einstein condensates with both two- and three-body interactions in a two-dimensional anhaxmonic trap （i.e., harmonic plus quartic trap） are investigated. By using the variational method, the influence of the three-body interaction and the anharmonicity on the stability axe discussed in detail. It is found that the anhaxmonicity of the trap and the three-body interaction have significant effect on the stability and collective excitations of the system.

关键词： Bose Einstein condensates stability anharmonicity three-body interaction