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Synthesis and Crystal Structure of N′-(4-fluorobenzylidene)-2-(1H-1,2,4-triazole-1-yl)acetohydrazide

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Chemical Research in Chinese Universities 2006年第5期22卷 571-573页

作者： LI Wei-hua ZHANG Shu-fang hou bao-rong YU Zhi-gang Institute of Oceanology Chinese Academy of Sciences Qingdao 266071 P. R. China College of Chemistry and Chemical Engineering Ocean University of China Qingdao 266033 P. R. China

N′-（4-fluorobenzylidene）-2-（ 1H-1,2,4-triasole-1-yl） acetohydrazide was synthesized by the reaction of 4-flu- orobenzaldehyde with 2-（ 1H-1,2,4-triazole-1-yl） acetohydrazide. The structure was confirmed via elemental analysis, MS, ^1H NMR, IR, and X-ray diffraction. It crystallized in a monoclinic system with space group P2 （ 1 ）, α = 0.4905（1） nm, b =0. 8160（2） nm, c = 1.4105（3） nm, β =93. 33（3）°, Z=2, V=0.5636（2） nm^3, Do =1.457 Mg/m^3,μ =0. 112 mm^-1 , F（000） =256, and final R1 =0. 0685. Several intermolecular hydrogen-bond interactions existed in the crystal structure, facilitating the stabilization of the compound.

关键词： 1H-1,2,4-Triazole Acetohydrazide Crystal structure Biological activity

Lower limit law of welding windows for explosive welding of dissimilar metals

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Journal of Iron and Steel Research International 2017年第8期24卷 852-857页

作者： Chang-gen Shi Xuan Yang Yu-heng Ge Jun You Hong-bao hou PI.A University of Science and Technology Nanjing 210007JiangsuChina Baicheng Ordnance Test Center Baicheng 137001JilinChina

The influence of explosive charge thickness on the quality of explosive welding of dissimilar metals was *** lower limit law should be followed in the course of explosive *** welding experiments of stainless steel（410S）and steel（Q345R）were carried out in three different kinds of explosive charge thicknesses,namely 15,25and *** of morphology and mechanical properties of three samples were observed and *** was found that micro and small wavy bonding is mainly formed for charge thickness of 15mm whose strength is the highest with minor deformation and few defects in the interface;small and middle wavy bonding are mainly formed for charge thickness of 25 mm whose strength is comparatively mediocre;big wavy bonding is mainly formed for charge thickness of 35 mm whose strength is the *** cause of high bonding strength of the micro and small wavy interface was analyzed and verified on the basis of the results of Electron Probe Micro-Analyzer（EPMA）tests of three selected samples.

关键词： Explosive welding Welding window Lower limit law Cladding plate Bonding interface

Effect of phosphate conversion film on fatigue and corrosion fatigue behavior of an as-rolled Mg–3.08Zn–0.83Al(in wt.%)alloy

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Journal of Iron and Steel Research International 2023年第12期30卷 2557-2565页

作者： bao-jie Wang Dao-kui Xu Shuo Wang Xiang-bo Xu En-hou Han School of Environmental and Chemical Engineering Shenyang Ligong UniversityShenyang110159LiaoningChina Key Laboratory of Nuclear Materials and Safety Assessment Institute of Metal ResearchChinese Academy of SciencesShenyang110016LiaoningChina Binzhou Institute of Technology Binzhou256606ShandongChina Shandong Key Laboratory of Advanced Aluminium Materials and Technology Binzhou256606ShandongChina Key Lab of Electromagnetic Processing of Materials Ministry of EducationNortheastern UniversityShenyang110819LiaoningChina

Through investigating and comparing the fatigue behavior of an as-rolled Mg–3.08Zn–0.83Al(in wt.%)alloy performing surface phosphate conversion film treatment,it revealed that the determined fatigue strength of surface treated samples at 106 cycles in air was 65 MPa,whereas the fatigue strength was only 35 MPa when tested in 3.5 wt.%NaCl *** analysis demonstrated that in air,the fatigue crack initiation was mainly dominated by the interaction between the retarding effect of phosphate conversion film on cyclic slips occurring in the underneath *** the matrix cannot endure the accumulated stress concentration due to the irreversibility of cyclic slips,the fatigue crack will preferentially initiate at sample *** the phosphate conversion film cracked easily under the cyclic loading and lost its protectiveness on the substrate in 3.5 wt.%NaCl solution,fatigue cracks were preferentially nucleated at the localized corrosion pits.

关键词： Mg alloy Corrosion fatigue Surface film Pitting Crack initiation

Investigation on Yield Behavior of 7075‑T6 Aluminum Alloy at Elevated Temperatures

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Chinese Journal of Mechanical Engineering 2020年第5期33卷 225-236页

作者： Jianping Lin Xingyu bao Yong hou Junying Min Xinlei Qu Zhimin Tao Jiajie Chen School of Mechanical Engineering Tongji UniversityShanghai 201804China Shandong Nanshan Aluminum Co. LtdShandong 265706China Pan Asia Technical Automotive Center Shanghai 202106China

Aluminum alloys have drawn considerable attention in the area of automotive *** strength aluminum alloys are usually deformed at elevated temperatures due to their poor formability at room *** this work,the yield behavior of 7075 aluminum alloy in T6 temper(AA7075-T6)within the temperature ranging from 25°C to 230°C was *** and biaxial tensile tests with the aid of induction heating system were performed to determine the stress *** curves and the yield loci of AA7075-T6 at elevated temperatures,*** Mises,Hill48 and Yld2000-2d yield criteria were applied to predicting yield loci which were compared with experimentally measured yield loci of the *** show that yield stress corresponding to the same equivalent plastic strain decreases with increasing temperature within the investigated temperature range and the shape of yield loci evolves nearly *** experimental yield locus expands with an increase of equivalent plastic strain at the same temperature and the work hardening rate of AA7075-T6 exhibits obvious *** nonquadratic Yld2000-2d yield criterion describes the yield surfaces of AA7075-T6 more accurately than the quadratic von Mises and Hill48 yield criteria,and an exponent of 14 in the Yld2000-2d yield function gives the optimal predictions for the AA7075-T6 at all investigated temperatures.

关键词： Aluminum alloy Yield behavior Biaxial tensile test Warm condition

Recent advances in screening active components from natural products based on bioaffinity techniques

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Acta Pharmaceutica Sinica B 2020年第10期10卷 1800-1813页

作者： Xiaofang hou Meng Sun Tao bao Xiaoyu Xie Fen Wei Sicen Wang School of Pharmacy Health Science CenterXi’an Jiaotong UniversityXi’an 710061China College of Pharmacy Shaanxi University of Chinese MedicineXi’an 712046China Shaanxi Engineering Research Center of Cardiovascular Drugs Screening&Analysis Xi’an 710061China

Natural products have provided numerous lead compounds for drug ***,the traditional analytical methods cannot detect most of these active components,especially at their usual low concentrations,from complex natural ***,we reviewed the recent technological advances(2015-2019)related to the separation and screening bioactive components from natural resources,especially the emerging screening methods based on the bioaffinity techniques,including biological chromatography,affinity electrophoresis,affinity mass spectroscopy,and the latest magnetic and optical *** screening methods are uniquely advanced compared to other traditional methods,and they can fish out the active components from complex natural products because of the affinity between target and components,without tedious separation ***,these new tools can reduce the time and cost of the drug discovery process and accelerate the development of more effective and better-targeted therapeutic agents.

关键词： Screening Active components Natural products Bioaffinity techniques

Remote sensing survey and research on internal solitary waves in the South China Sea-Western Pacific-East Indian Ocean(SCS-WPAC-EIND)

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Acta Oceanologica Sinica 2022年第10期41卷 154-170页

作者： Junmin Meng Lina Sun Hao Zhang Beilei Hu Fucheng hou Sude bao First Institute of Oceanography Ministry of Natural ResourcesQingdao266061China Technology Innovation Center for Ocean Telemetry Ministry of Natural ResourcesQingdao266061China

Internal solitary waves(ISWs)are common mesoscale dynamic processes in the ocean that are spread throughout the world’s *** South China Sea(SCS),Western Pacific(WPAC)and Indian Ocean(EIND)(SCS-WPACEIND)are areas where ISWs frequently *** particular,in the northern part of the South China Sea,Sulu Sea,Celebes Sea,Andaman Sea,Lombok Strait and northeastern part of Taiwan Island,ISWs exist almost *** sensing is an important technique to carry out investigations and research on ISWs on a large *** particular,optical sensors represented by the Moderate Resolution Imaging Spectroradiometer(MODIS)can observe ISWs for a long time and on a large scale,while SAR sensors such as Sentinel-1 A/B can compensate for the deficiencies in optical sensors and comprehensively observe *** on many years of remote sensing surveys of ISWs,this paper uses MODIS and Sentinel-1 satellite remote sensing images of more than 70000 scenes from 2010 to 2020 to carry out survey studies of ISWs in the *** survey systematically gives the temporal and spatial distribution characteristics of ISWs in the SCS-WPAC-EIND and focuses on the analysis of the ISW characteristics in main areas in the SCS-WPAC-EIND,thereby providing basic data for further research on ISWs.

关键词： internal solitary waves SCS-WPAC-EIND remote sensing MODIS Sentinel-1A/B

Symmetries and Mei Conserved Quantities of Nonholonomic Controllable Mechanical Systems

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Communications in Theoretical Physics 2006年第3X期46卷 415-418页

作者： XIA Li-Li LI Yuan-Cheng WANG Jing hou Qi-bao College of Physics Science and Technology China University of Petroleum Dongying 257061 China

This paper concentrates on studying the symmetries and a new type of conserved quantities called Mei conserved quantity. The criterions of the Mei symmetry, the Noether symmetry and the Lie symmetry are given. The conditions and the forms of the Mei conserved quantities deduced from these three symmetries are obtained. An example is given to illustrate the application of the result.

关键词： control nonholonomic mechanical system Mei symmetry Noether symmetry Lie symmetry conserved quantity

Interactive Effects of Elevated CO_2 and Temperature on Rice Planthopper, Nilaparvata lugens

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Journal of Integrative Agriculture 2014年第7期13卷 1520-1529页

作者： SHI bao-kun HUANG Jian-li HU Chao-xing hou Mao-lin State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Sciences

It is predicted that the current atmospheric CO2 concentration will be doubled and global mean temperature will increase by 1.5-6＆#176;C by the end of this century. Although a number of studies have addressed the separate effects of CO2 and temperature on plant-insect interactions, few have concerned with their combined impacts. In the current study, a factorial experiment was carried out to examine the effect of a doubling CO2 concentration and a 3℃ temperature increase on a complete generation of the brown planthopper （Nilaparvata lugens） on rice （Oryza sativa）. Both elevated CO2 and temperature increased rice stem height and biomass of stem parts. Leaf chlorophyll content increased under elevated CO2, but only in ambient temperature treatment. Water content of stem parts was reduced under elevated temperature, but only when coupled with elevated CO2. Elevated CO2 alone increased biomass of root and elevated temperature alone enhanced leaf area and reduced ratio of root to stem parts. Brown planthopper （BPH） nymphal development was accelerated, and weight of and honeydew excretion by the F1 adults was reduced under elevated temperature only. Longevity of brachypterous females was affected by a signiifcant interaction between CO2 and temperature. At elevated temperature, CO2 had no effect on female longevity, but at ambient temperature, the females lived shorter under elevated CO2. Female fecundity was higher at elevated than at ambient temperature and higher at elevated CO2 than at ambient CO2. These results indicate that the combined effects of elevated temperature and CO2 may enhance the brown planthopper population size.

关键词： climate change elevated CO2 global warming Nilaparvata lugens rice development

An energy conduction model for cell image segmentation

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Chinese Science Bulletin 2011年第10期56卷 1048-1054页

作者： MA JingFeng BU JiaJun hou Kai bao ShangLian CHEN Chun College of Computer Science and Technology Zhejiang University Hangzhou 310027 China Beijing Key Laboratory of Medical Physics and Engineering Peking University Beijing 100871 China Beijing Healthway Technology Limited Company Beijing 100084 China

Cell image segmentation is an essential step in cytopathological *** their execution speed is fast,the results of cell image segmentation by conventional pixel-based,edge-based and continuity-based methods are often *** structures in a cell image can be obtained with a method that quickly adjusts the threshold ***,the processing time of such a method is usually long and the final results may be sensitive to intensity differences and other *** this article,a new energy model is proposed that synthesizes a differential equation from the conventional and level set methods,and utilizes the nonuniformity property of cell images (*** are more uneven than the background).The feasibility and robustness of the proposed model was demonstrated by processing relatively complicated background images of both simulated and real cell images.

关键词：细胞图像图像分割传导模型水平集方法能量执行速度精细结构快速调整