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Erosive Wear and Wear Mechanism of in situ TiC_P/Fe Composites

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Journal of Materials science & technology 2005年第5期21卷 719-723页

作者： Zhaojing LIU, Zhiliang NING , Fengzhen LI, Xiurong YAO and Shanzhi RENSchool of Materials science and Engineering, harbin university of science and technology, harbin 150080, china School of Materials science and Engineering Harbin University of Science and Technology Harbin 150080 China

The base structure of in situ TiCp/Fe composites fabricated under industrial condition was changed by different heat treatments. Erosive wear tests were carried out and the results were compared with that of wear-resistant white cast iron. The results suggest that the wear resistance of the in situ TiCp/Fe composite is higher than that of wear-resistant white cast iron under the sand erosive wear condition. The wear mechanism of the wear-resistant white cast iron was a cycle process that base surface was worn and carbides were exposed, then carbides was broken and wear pits appeared. While the wear mechanism of in situ TiCp/Fe composite was a cycle process that base surface was worn and TiC grains were exposed and dropped. The wear resistance of in situ TiCp/Fe composite was lower than that of wear-resistant white cast iron under the slurry erosive wear condition. Under such circumstance, the material was not only undergone erosive wear but also electrochemistry erosion due to the contact with water in the medium. The wear behaviours can be a combination of two kinds of wear and the sand erosive wear is worse than slurry erosive wear.

关键词： In situ TiCp/Fe composite Erosive wear Wear mechanism

TECHNIQUES ABOUT DIRECT OPTIMIZING CONTROL OF GREEN SAND QUALITY

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Chinese Journal of Mechanical Engineering 2002年第1期15卷 83-86,93页

作者： Li Dayong Xu Xiongfei Ma Xuliang Zhang Yutong School of Material science and Engineering，harbin university of science and technology， harbin 150080，china School of Material science and Engineering Harbin University of Science and Technology Harbin 150080

Green sand casting is still a main method in the world at present and it isvery significant to develop the technology of controlling green sand quality. A new concept, fromcontents test to contents control, is advanced. In order to realize the new idea, a new method toon-line test active clay and moisture of green sand - double powers energizing alternately (DPEA)method is put forwards. The principle of the new method is to energize standard sand sample with ACand DC powers and to test the electric parameters, and then, to calculate active clay and moistureof green sand by using artificial neural network (ANN). Based on this new method, a directoptimizing system for controlling green sand quality is developed. Techniques about testing andcontrolling methods, hardware and software are discussed.

关键词： New technology Green sand quality Optimizing control

TENSILE FRACURE IN AN Al-Li ALLOY 8090

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中国有色金属学会会刊：英文版 1995年第2期5卷 106-108页

作者： Jiang, Daming Wang,Yinong Hong, Bande Lei, Tingquan(harbin Institute of technology, harbin 150080)Sun Fenglian(harbin university of science and technology, harbin 150001) harbin Inst of technology Harbin China

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关键词： Al-Li alloy tensile fracture dimple rupture cleavage

The estimation-valued property of B-valued asymptotic martingale

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Progress in Natural science:Materials International 2006年第7期16卷 773-776页

作者： KONG Fanliang (Department of Mathematics, harbin university of science and technology, harbin 150080, china) harbin Univ Sci & Technol Dept Math Harbin 150080 Peoples R China

In this paper, with the Doob decomposition of B-valued asymptotic martingale, we study the estimation-valued property of B-valued asymptotic martingale in Banach space B, which has the Radon-Nikodym Property and is du... 详细信息

关键词： Banach space asymptotic martingale Doob decomposition uniformly compact bounded variation topological convergence.

Landscape Change and its effect on the environment of Daqing City

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Progress in Natural science:Materials International 2005年第7期15卷 641-649页

作者： ZANG Shuying, ZHANG Jing and JIA Li ( college of Life and Environment science, harbin Normal university, harbin 150080, china college of Resources Environment & Tourism, Capital Normal university, Beijing 100037, china college of Economics and Management, Northeast Agricultural university, harbin 150030, china) college of Life and Environment science Harbin Normal University Harbin 150080 China. college of Resources Environment & Tourism Capital Normal University Beijing 100037 China. college of Economics and Management Northeast Agricultural University Harbin 150030 China

In this paper, we will study the temporal-spatial landscape change from 1978 to 2001 in Daqing City, based on the mul- ti spectral scanner (MSS) and thematic mapper (TM) images of remote sensing (RS) of 1978, 1988, 1992, 1996 and 2001. In order to explain the effects of the component change on the whole landscape, we make a statistic analysis about the transfer probability matrix of the component types of the landscape by using the ARCGIS platform through the overlay analysis of different landscape components. Based on the transfer probability matrix, we calculate the in-transfer ratio, the out-transfer ratio and the contributor ratio of the special transfer process of the main landscape components. The results illustrate that the cultivated-land, grassland, swamp, and alkaline land are the main contributors resulting in the landscape change: the out-transfer ratios of grassland and swamp are much higher than the in-transfer ones; the in-transfer ratio of alkaline land is much higher than the out-transfer one; the in-transfer ratio of the land-lot is always higher than its out-transfer with the highest rate per year, although there is a small difference among the in-transfers and the out-transfers per year. The main landscape changing processes are the salination of cultivated-land, salination or desertification of grassland, salination and degeneration of swamp. Results in this paper can provide scientific basis for investigating the landscape change mechanism of resources-based city.

关键词： landscape change environmental effect transfer probability resources-based city.

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.

WEAR AND LIFE　OF　PCBN　TOOLS WHEN DRY-CUTTING　BEARING　STEEL　GCr15

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Chinese Journal of Mechanical Engineering 2002年第3期15卷 218-221页

作者： Liu Xianli Zhang Zhongmin Li ZhenjiaDepartment of Mechanical Engingeering, harbin university of science and technology,harbin 150080, chinaLiu Linjiang Yuan ZhejunJilin university harbin Institute of technology *** Department of Mechanical Engingeering Harbin University of Science and Technology Harbin 150080 China

The wear forms and reasons of PCBN tools when dry-cutting bearing steel GCr15are studied systematically. The effect law of the workpiece hardness on PCBN tools is gained andtool wearing with the quickest speed at the workpiece critical hardness is proved. The life equationat two kinds of workpiece hardness demonstrates that the effect of the cutting speed on the PCBNtool life is less than that of carbide tools and ceramic tools.

关键词： Dry-cutting PCBN tool Tool wear Tool life Bearing steel GCr15

Cell cycle-dependent gene networks relevant to cancer

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Progress in Natural science:Materials International 2008年第8期18卷 945-952页

作者： Yun Xiao a,1, Xia Lia,b,*,1, Yueying Yang a, Yadong Wangc, Shaoqi Rao a,b a college of Bioinformatics science and technology, and Bio-pharmaceutical Key Laboratory of Heilongjiang Province and State, harbin Medical university, harbin 150086, china b Biomedical Engineering Institute of Capital Medical university, Beijing 10004, china c Department of Computer science, harbin Institute of technology, harbin 150080, china college of Bioinformatics science and technology and Bio-pharmaceutical Key Laboratory of Heilongjiang Province and State Harbin Medical University Harbin 150086 China Biomedical Engineering Institute of Capital Medical university Beijing 10004 China Department of Computer science Harbin Institute of Technology Harbin 150080 China

The analysis of sophisticated interplays between cell cycle-dependent genes in a disease condition is one of the largely unexplored areas in modern tumor biology research. Many cell cycle-dependent genes are either oncogenes or suppressor genes, or are closely associated with the transition of a cell cycle. However, it is unclear how the complicated relationships between these cell cycle-dependent genes are, especially in cancers. Here, we sought to identify significant expression relationships between cell cycle-dependent genes by analyzing a HeLa microarray dataset using a local alignment algorithm and constructed a gene transcriptional network specific to the cancer by assembling these newly identified gene-gene relationships. We further characterized this global network by partitioning the whole network into several cell cycle phase-specific sub-networks. All generated networks exhibited the power-law node-degree distribution, and the average clustering coefficients of these networks were remarkably higher than those of pure scale-free networks, indicating a property of hierarchical modularity. Based on the known protein-protein interactions and Gene Ontology annotation data, the proteins encoded by cell cycle-dependent interacting genes tended to share the same biological functions or to be involved in the same biological processes, rather than interacting by physical means. Finally, we identified the hub genes related to cancer based on the topological importance that maintain the basic structure of cell cycle-dependent gene networks.

关键词： Cell cycle Microarray HeLa cell Gene network

Synthesis and magnetic properties of CdS/α-Fe_2O_3 hierarchical nanostructures

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science china(Physics,Mechanics & Astronomy) 2009年第7期52卷 997-1002页

作者： CHEN YuJin1,2,3, SHI XiaoLing1, CAO MaoSheng1 & ZHU ChunLing4 1 School of Materials science and Engineering, Beijing Institute of technology, Beijing 100081, china 2 Micro-Nano Technologies Research Center, Hunan university, Changsha 410082, china 3 college of science, harbin Engineering university, harbin 150001, china 4 college of Material science and Chemical Engineering, harbin Engineering university, harbin 150001, china School of Materials science and Engineering Beijing Institute of Technology Beijing China Micro-Nano Technologies Research Center Hunan University Changsha China college of science Harbin Engineering University Harbin China college of Material science and Chemical Engineering Harbin Engineering University Harbin China

CdS/α-Fe2O3 hierarchical nanostructures, where the CdS nanorods grow irregularly on the side surface of α-Fe2O3 nanorods, were synthesized via a three-step process. The diameters and lengths of CdS nanorods can be tuned by changing the ethylenediamine (EDA) and Cd ion concentrations. The magnetic investigations by superconducting quantum interference device indicate that the hierarchical nanostructures have an Morin transition at lower temperature (230 K) than that of the single bulk α-Fe2O3 materials (263 K). Importantly, the hierarchical nanostructures exhibit weakly ferromagnetic characteristics at 300 K. A sharp peak assigned to the surface trap induced emission are observed in room temperature PL spectra. Combining with the optoelectronic properties of CdS, the CdS/ α-Fe2O3 hierarchical nanostructures may be used as multi-functional materials for optoelectronic and magnetic devices.

关键词： α-Fe2O3 CdS hierarchical nanostructures magnetic properties