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Acta Metallurgica Sinica(English Letters) 1992年第9期5卷 178-182页

作者： QIAO Lijie LIU Rui XIAO Jimei University of science and technology {2.,{2.,china

The effects of stress components on nucleation sites and propagation directions of stress cor- rosion cracks in brass were investigated with specimens under mode Ⅱ and mode Ⅲ loadings. The results indicated that under mode Ⅱ loading,stress corrosion cracks nucleated on the site with maximum normal stress component and propagated along the plane perpendieular to the maximum normal stress,under mode Ⅲ loading,the stress corrosion crack was not evident on the 45°plane due to the general corrosion in aqueous solution with high NH_4OH concentra- tion,while stress corroded in aqueous solution with low NH_4OH concentration, numerous cracks with spacings of 10—150μm were found on the 45°plane with maximum normal stress and no stress corrosion cracks was observed on the plane with maximum shear stress.

关键词： stress corrosion cracking stress compoonent brass ammonia solution

Focus on polymer chemistry papers in science in china Series B:Chemistry of the year 2.09

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science china Chemistry 2010年第12期53卷 2663-2664页

作者： TIAN Ying science china Press,16 Donghuangchenggen North Street,{2. 100717,china science china Press Beijing China

The journal science in china Series B:Chemistry published 11 and 37 papers in polymer fields in 2.08 and 2.09,respectively,leading to a percentage increase of 2.6% and thereby a great historic breakthrough of the *** papers mainly focus on three fields:(1) polymer synthesis,(2. functional polymer materials and (3) biomedical *** research groups published a series of papers in science in china Series B:Chemistry and detailedly introduced their works in the related fields.

关键词： BZ ZK ATRP Focus on polymer chemistry papers in science in china Series B PDMAEMA

Role of science and technology in environmentally sound urbanization in {2.

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Journal of Environmental sciences 1999年第3期11卷 298-302页

作者： Qin Da\|he, Liu Jian Bureau of science and technology for Resources and Environment, Chinese Academy of sciences, beijing\ 100864, china Bur. Sci. Technol. Rsrc. Environ. Chinese Academy of Sciences Beijing 100864 China

In the process of accelerating industrialization, urbanization is inevitable and important to chinas modernization drive. While people are cherishing the advantages of living in cities, the increasing negative impact of urbanization has to be put on the top of priority list. As urbanization proceeds, the existing pollution problem aggravates with not only increasing quantity of pollutants, but diversity as well. science and {2. have been contributing to urbanization process in both positive and negative ways. Nonetheless, the role of science and {2. in promoting sustainable urbanization is increasingly important. china has been conducting environmental research and development since the early 1970s, and now is capable of supplying most technologies needed for urban environmental protection. To keep pace with the rapid urbanization process in china, environmental research and {2. development should be strengthened. This is mostly dependent on domestic resources with introduction of advanced yet cost\|effective technologies from the rest of the world. With a survey of current urban environmental R & D in china and on\|going activities of the Chinese Academy of sciences (CAS), recommendations on future UCL(University College London)\|CAS collaboration in the domain of urban environment are made.

关键词： science technology urbanization environment.

Density functional theory study of the reaction paths of reactions of CH3C（O）O2.radicals with HO2.in the gas phase

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Progress in Natural science:Materials International 2006年第12期16卷 1269-1274页

作者： ZHOU Yuzhi~ 1,2., ZHANG Shaowen~1 and LI Qianshu~1**(1. State Key Laboratory of Explosion science and technology, {2. Institute of technology, {2. 100081, china 2. {2. Institute of Education, {2. 100044, china) State Key Laboratory of Explosion science and technology Beijing Institute of Technology Beijing 100081 China beijing Institute of Education Beijing 100044 China

A DFT study on the reactions between CH_3C（O）O_2.nd HO_2.adicals has been carried out. It is suggested that both the triplet and singlet potential surfaces involve a complex mechanism with the formation of loosely bound intermediate complexes of reactants and products. The reaction prefers to occur on the triplet surface to produce peracetic acid (CH_3C（O）O_2.) and triplet O_2.olecule. The CH_3C（O）O_2. can further convert into CH_3C（O）O and HO radicals.

关键词： acetyl peroxy radicals HO2.radicals reaction mechanism DFT.

Remarks on Hard Lefschetz conjectures on Chow groups Dedicated in celebration of science china on the occasion of its 60th birthday

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science china Mathematics 2010年第1期53卷 105-114页

作者： FU BaoHua Institute of Mathematics, Academy of Mathematic and Systems science, Chinese Academy of sciences, {2. 100190, china Institute of Mathematics Academy of Mathematic and Systems Science Chinese Academy of Sciences Beijing China

We propose two conjectures of Hard Lefschetz type on Chow groups and prove them for some special cases. For abelian varieties, we show that they are equivalent to the well-known conjectures of Beauville and Murre.

关键词： Chow groups abelian varieties Bloch-Beilinson conjectures Beauville conjecture Murre conjecture

Tuning surface active oxygen of lanthanum oxide via partial dissolution and regrowth of crystallites

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Journal of Natural Gas Chemistry 2011年第5期20卷 483-486页

作者： Zhiming Gao, Huili Li Key Laboratory of Cluster science, ministry of Education of {2. Department of Chemistry, School of science, beijing Institute of technology, beijing 100081, {2. Key Laboratory of Cluster science Ministry of Education of China Department of Chemistry School of Science Beijing Institute of Technology Beijing 100081 China

A commercial lanthanum oxide was modified into X%-La2.3 samples via partial dissolution and regrowth of crystallites, wherein the X value denotes the weight percent of the initial metal oxide powder dissolved by nitric acid. BET measurements and TEM observations indicate that the 2.%-La2.3 sample has an increased specific surface area, relatively thin and small crystallites in size. TPD/TPR profiles also show that the 2.%-La2.3 sample has more surface active oxygen than the 0%-La2.3 sample. Among the four X%-La2.3 samples, the highest activity for methane oxidation was obtained over the 2.%-La2.3 sample. Therefore, the present work proves that the method of partial dissolution and regrowth of crystallites are effective to modify surface property of lanthanum oxide.

关键词： solid state reaction surface oxygen crystallite regrowth TPR metal oxide

Flotation Separating Rutile from Calcium and Silicon Gangue Minerals

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Rare Metals 2001年第4期20卷 205-208页

作者： Hao Ding1, HaiLin 2.1) beijing Academy of Building Materials, beijing 100041, {2. 2. University of science and technology beijing, beijing 100083, {2. 北京建筑材料研究院北京 100041 北京科技大学北京 100083

Rutile separation from calcite, apatite and quartz by flotation was investigated. The results show that the rutile separation from calcium and silicon gangue minerals can be realized with alkyl-imino-bismethylene phos... 详细信息

关键词： rutile calcium and silicon gangue minerals flotation separate alkyl-imino-bismethylene phosphoric acid sodium hexametaphosphate

The mathematical model of wetting angle of heterogeneous nucleation

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science china(Technological sciences) 2004年第4期47卷 391-397页

作者： HUANG Cheng1, SONG Bo1, MAO Jinghong2.& ZHAO Pei3 1. School of Metallurgical and Ecological Engineering, University of science and technology {2., {2. 100083, china 2. School of Material science, University of science and technology {2., {2. 100083, china 3. Central Iron and Steel Research Institute, {2. 100081, china School of Metallurgical and Ecological Engineering University of Science and Technology Beijing Beijing China School of Material science University of Science and Technology Beijing Beijing China Central Iron and Steel Research Institute Beijing China

The heterogeneous nucleation has been analyzed in terms of the thermodynamic theory, and the mathematical model of wetting angle of heterogeneous nucleation has been developed based on the dynamic requirements of hetero- and homogeneous nucleation. With the wetting angel model, the wetting angles of different catalysts in liquid iron have been calculated. The result shows that the wetting angle of most catalysts is smaller than 40, and the value of f() is far less than 1. The wetting angles of TiN, TiC and RE2.3 are smaller, while the wetting angle of MnO is bigger among the ordinary nucleation catalysts. The wetting angles calculated by this model are in agreement with the results of other research work.

关键词： heterogeneous nucleation, mathematical model, wetting angle, undercooling.

Structure and kinematic analysis of a novel 2.DOF translational parallel robot

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Progress in Natural science:Materials International 2007年第10期17卷 1213-1219页

作者： Chen Tao1, Wu Chao2.and Liu Xinjun2.1. School of Application science and technology, Harbin University of science and technology, Harbin 150080, china 2. Department of Precision Instruments, Tsinghua University, beijing 100084, china) School of Application science and technology Harbin University of Science and Technology Harbin 150080 China Department of Precision Instruments Tsinghua University Beijing 100084 China

This paper addresses the analysis of a novel parallel robot with 2.translational degrees of freedom (DOFs). The robot can position a rigid body in a plane with constant orientation. The kinematic structure of the robot is first described in detail. Some kinematic problems, such as the inverse and forward kinematics, velocity, and singularity are then analyzed. The working and assembly modes are discussed. Since it is the most important index to design a robot, the workspace of the robot is studied systematically in this paper. Based on the analysis of reachable workspace and singularity, a kind of workspace concept characterizing the region that the end-effector of the robot can reach in practice is defined. The results of this paper will be very useful for the design and application of the robot.

关键词： parallel robot degree of freedom kinematics workspace.

Recommendation Method for Contrastive Enhancement of Neighborhood Information

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Computers, Materials & Continua 2024年第1期78卷 453-472页

作者： Hairong Wang beijing Zhou Lisi Zhang He Ma School of Computer science and Engineering North Minzu UniversityNingxia750021China

Knowledge graph can assist in improving recommendation performance and is widely applied in various person-alized recommendation ***,existing knowledge-aware recommendation methods face challenges such as weak user-item interaction supervisory signals and noise in the knowledge *** tackle these issues,this paper proposes a neighbor information contrast-enhanced recommendation method by adding subtle noise to construct contrast views and employing contrastive learning to strengthen supervisory signals and reduce knowledge ***,first,this paper adopts heterogeneous propagation and knowledge-aware attention networks to obtain multi-order neighbor embedding of users and items,mining the high-order neighbor informa-tion of users and ***,in the neighbor information,this paper introduces weak noise following a uniform distribution to construct neighbor contrast views,effectively reducing the time overhead of view *** paper then performs contrastive learning between neighbor views to promote the uniformity of view information,adjusting the neighbor structure,and achieving the goal of reducing the knowledge noise in the knowledge ***,this paper introduces multi-task learning to mitigate the problem of weak supervisory *** validate the effectiveness of our method,experiments are conducted on theMovieLens-1M,MovieLens-2.M,Book-Crossing,and Last-FM *** results showthat compared to the best baselines,our method shows significant improvements in AUC and F1.

关键词： Contrastive learning knowledge graph recommendation method