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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 beijing,beijing,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—15.μm 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

7th CIIE likely to prove solid growth platform for many companies

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china Textile 2024年第4期 20-21页

作者： Editorial department of china Daily

The robust demand of the Chinese market and the improving business environment in the country make china a big growth opportunity for companies wishing to further expand their operations,said corporates that have registered to participate at this year's china International Import *** 7th edition of the annual CIIE,to be held in Shanghai from Nov 5.to 10,started its 100-day countdown on Saturday.

关键词： companies likely operations

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STATISTICAL EVALUATION OF CRITICAL INCLUSION FACTOR FOR SECONDARY RECRYSTALLIZATON IN 3%Si STEEL Lecturer,department of Materials Engineering,Southwestern Jiaotong university,Chengdu 610031,china

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Acta Metallurgica Sinica(English Letters) 1990年第5期3卷 327-331页

作者： LI Shuchen Southwestern Jiaotong university,Chengdu,chinaCHEN Mengzhe KE Jun university of Science and Technology beijing,beijing,china

On the basis of statistical data of MnS in the conventional 3% Si steel sheeets after various annealing processes,the critical inclusion factor has been evaluated to be 20 mm^(-1).The inhi- bition of MnS to grain grow... 详细信息

关键词： 3%Si steel secondary recrystallization inclusion factor

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-20M,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

Implementation of a multiple round quantum dense coding using nuclear magnetic resonance

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Science china(Physics,Mechanics & Astronomy) 2005年第6期48卷 706-715页

作者： ZHANG Jingfu1, XIE Jingyi2, WANG Chuan1, DENG Zhiwei3, LU Zhiheng4, & LONG Guilu1,5.1. Key Laboratory For Quantum Information and Measurements of MOE, department of Physics, Tsinghua university, beijing 100084,china 2. department of Materials Science and Engineering, beijing Normal university, beijing 100875. china 3. Testing and Analytical Center, beijing Normal university, beijing 100875.china 4. department of Physics, beijing Normal university, beijing 100875. china 5. Key Laboratory For atomic and Molecular Nanosciences, Tsinghua university, beijing 100084,china Key Laboratory For Quantum Information and Measurements Department of Physics Tsinghua University Beijing 100084 China department of Materials Science and Engineering Beijing Normal University Beijing 100875 China Testing and Analytical Center Beijing Normal University Beijing 100875 China department of Physics Beijing Normal University Beijing 100875 China Key Laboratory for Atomic and Molecular Nanosciences Tsinghua University Beijing 100084 China

A multiple round quantum dense coding scheme based on the quantum phase estimation algorithm is proposed and implemented in a three qubit nuclear magnetic resonance (NMR) quantum computer. Using an m + 1 qubit system, Bob can transmit one of 2m+1 messages to Alice, through manipulating only one qubit and exchanging it between Alice and Bob for m rounds. The information capacity is enhanced to m + 1 bits as compared to m bits in a classical scheme. The scheme has been demonstrated in NMR system, and the experimental results show a good agreement between theory and experiment.

关键词： quantum dense coding, multiple round, nuclear magnetic resorance

Electrical Properties of Expanded Graphite Intercalation Compounds

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Journal of Materials Science & Technology 2001年第3期17卷 371-374页

作者： Xiuyun CHUAN department of geology, Peking university, beijing 100871, china Daizhang CHEN and Xunruo ZHOU department of Materials Science, china university of Geosciences, beijing 100083, china E-mail: cxyljhcj@*** Dept. of Geol. Beijing Univ. Beijing 100871 China

The intercalation compounds of CuCl2 were synthesized with expanded graphite, whose magnitude of the electrical conductivity is about 10(3)S(.)cm(-1). Their electrical conductivity is 3 similar to6 times as high as that of the expanded graphite, and about 10 times as high as that of GIC made of the non-expanded graphite. The microanalysis results of chemical compounds by X-ray energy spectrum scanning of TEM testified that the atomic ratio of chloride and cupric is nonstoichoimetric. The multivalence and exchange of electrovalence of the cupric ion was confirmed by the XPS-ESCA. Vacancy of chlorine anion increases the concentration of charge carrier. The special stage structure, made of graphite and chloride, produces a weak chemical bond belt and provides a carrier space in the direction of GIC layer. These factors develop the electrical properties.

关键词： In Ph Electrical Properties of Expanded Graphite Intercalation Compounds Graphite ESCA

THE PHYSICAL ENTROPY OF SINGLE CONSERVATION LAWS

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Journal of Computational Mathematics 1998年第5期16卷 437-444页

作者： (department of Mathematics, Peking university, beijing 100871, china) 北京大学数学系北京

By means of the comparisons with the formulas in statistical mechanics and thermodynamics, in this paper it is demonstrated that for the single conservation law partial derivative(t)u + partial derivative(x)f(u) = 0, if the flux function f(u) is convex (or concave), then, the physical entropy is S = -f(u); Furthermore, if we assume this result can be generalized to any f(u) with two order continuous derivative, from the thermodynamical principle that the local entropy production must be non-negative, one entropy inequality is derived, by which the O.A. Olejnik's famous E- condition can be explained successfully in physics.

关键词： conservation laws entropy entropy production

Tectonic Units and Their Fundamental Characteristics on the Northern Margin of the Alxa Block

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Acta Geologica Sinica(English Edition) 1993年第4期67卷 373-385页

作者： Wu Tairan geology department, china university of Geosciences, beijing and He Guoqi geology department, Peking university Jiang Minxi geology department China University of Geosciences Beijing China

The northern margin of the Alxa block is the junction of a tectonic units. Four first-order tectonic units are distinguished: 1. the Yagan structural zone characteristic of an immature island arc; 2. the Zhusileng-Hangwula structural zone, which was a passive continental margin in the Early Palaeozoic and was transformed into an active continental margin in the Late Palaeozoic;3. the Shalazha structural zone characteristic of a mature island arc; 4. the Nuru-Langshan structural zone, which was a Proterozoic orogenic belt and later evolved into an extensional transtional crust in the Palaeozoic. The above-mentioned tectonic units differ remarkably in sedimentary formations, magmatic rock associations, metamorphism and geochemistry and are bounded by faults between one another.

关键词： Alxa structural zone boundary rock association

L~∞ CONVERGENCE OF TRUNC ELEMENT FOR THE BIHARMONIC EQUATION

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Journal of Computational Mathematics 1997年第1期15卷 14-22页

作者： M. Wang(department of Mathematics, beijing university, beijing, china) 北京大学数学系北京

The paper considers the L∞ convergence for TRUNC finite elements solving the boundary value problems of the biharmonic equation. The nearly optimal L∞ estimates for the error of first order derivatives are *** TRUNC plate element is proposed and developed by Argyris et al.. The numerical experiences show that the element has very good .***,[1l2]. The mathematicalproof of convergence of the TRUNC element is given by Shi Zong-ci in paper [3]. Thispaper will consider the L~∞ convergence for the TRUNC plate element.

关键词：双谐波方程边值问题收敛性有限元法

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Science china Earth Sciences 2004年第10期47卷 886-895页

作者： TANG Liangjie1,2, JIA Chengzao3, PI Xuejun4, CHEN Suping1,2, WANG Zhiyu5. XIE Huiwen4 1. Key Laboratory for Hydrocarbon Accumulation of Education Ministry, beijing 102.4., china 2. Basin & Reservoir Research Center, university of petroleum, beijing 102.4., china 3. Petro{5. Company Limited, beijing 100011, china 4. Tarim Oilfield Company, Petro{5. Company Ltd., Kurle 841000, china 5. department of geology, university of petroleum, beijing 102.4., china Key Laboratory for Hydrocarbon Accumulation of Education Ministry Beijing China Basin & Reservoir Research Center University of Petroleum Beijing China Petrochina Company Limited Beijing China Tarim Oilfield Company PetroChina Company Ltd. Kurle China department of geology University of Petroleum Beijing China

The salt beds of Lower Tertiary developed in the mid-segment of Kuqa foreland fold belt, northern Tarim basin. They considerably controlled structural deformation of the belt. Ac- cording to the field observation, seismic profile interpretation and drilling data, three different structural styles of supra-salt, intra-salt and sub-salt occurred in the Kuqa foreland fold belt. Su- pra-salt structural styles mainly include thrust faults and fault-related sags. Intra-slat structural styles essentially are salt-pillows, intra-salt faults and folds, and salt weld structures. Sub-salt structural styles mainly consist of imbricated thrust faults, duplex structures, pop-up and fault-related folds. It is indicated that great differences exist among supra-salt, intra-salt and sub-salt structures of Kuqa foreland fold belt. The salt-related structures were formed in the same structural stress field. The dynamic mechanism of the salt-related structures is mainly associated with gravitation, compression and plastic flow of salt beds.

关键词： salt-related structural style, supra-salt structure, intra-salt structure, sub-salt structure, Kuga foreland fold belt.