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The characteristics of arc beam shaping in hybrid plasma and laser deposition manufacturing

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Science China(Technological Sciences) 2006年第2期49卷 238-247页

作者： ZHANG Hai’ou1. QIAN Yingping1.3. WANG Guilan1.& ZHENG Qiguang2 1. School of Material Science and Technology, Huazhong University of Science and Technology, Wuhan 43.074, China 2. Institute of Laser Technology and engineering, Huazhong University of Science and Technology, Wuhan 43.074, China {1., Hubei University of Technology, Wuhan 43.068, China 1. School of Material Science and Technology Huazhong University of Science and Technology Wuhan 430074 China 3. mechanical engineering college Hubei University of Technology Wuhan 430068 China 2. Institute of Laser Technology and engineering Huazhong University of Science and Technology Wuhan 430074 China

As a new direct metal prototyping technology,the hybrid plasma and laser deposition manufacturing (PLDM) is proposed in this paper. In order to figure out the characteristics of plasma arc beam and mould in the PLDM process of high temperature alloy, the high speed CCD camera is used to obtain the picture around the plasma arc. Afterwards the sketch of picture is clearly obtained. And the effect of laser parameter, such as average power, pulse width, pulse repetition frequency and the angle between laser beam and plasma arc beam on the plasma arc appearance, is studied experimentally. The results show that the modality of plasma arc beam is markedly influenced by laser beam. And the improvements of shape precision and surface state of the layer deposited by PLDM are confirmed.

关键词： plasma hybrid laser, direct deposition, plasma arc beam, molding character, high-temperature alloy.

Mathematic Expression of Kinetic Compensation Effect and Relationship between the Exothermic Decomposition Temperature and Critical Temperature of Thermal Explosion of Eighty-six Energetic Materials

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含能材料 2001年第1期9卷 8-9页

作者： HU Rong zu 1. YANG De suo 2, ZHANG Jiao qiang 3. (1. Department of Chemistry,Northwest University, Xi′an 71.065, China 2. Department of Chemistry and Chemical {1., Baoji {1. of Arts and Science, Baoji 721.07, China 3. Department of 西北大学陕西西安 710065 宝鸡文理学院陕西 721007 西北工业大学陕西西安 710072

Two relationships are established using the least squares method,between the kinetic parameters (the apparent activation energy and pre exponential constant),and the exothermic decomposition temperature and ther... 详细信息

关键词： critical temperature of thermal explosion decomposition temperature DSC energetic materials.

Interfacial Microstructure and Properties of Ti(C, N)/Ni Bonded by Transient Liquid-phase Diffusion

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Journal of Wuhan University of Technology(Materials Science) 2009年第3期24卷 432-439页

作者：周世权熊惟皓 School of mechanical Science and {1. Huazhong University of Science and Technology Department of mechanical {1. University of Waterloo School of Materials Science and engineering Huazhong University of Science and Technology

Effects of the main process parameters（temperature and time） on microstructure and properties of Ti（C, N）/Ni interface bonded by （Cu＋Nb） interlayer in a vacuum diffusion bonding device were investigated. The interfacial microstructures consisted initially of Ni3.b metallic compound and eutectic of Ni3.b ＋ CuNiss, and finally transformed to （Ti, Nb）（C, N）＋Ni3.b near Ti （C, N） and NiCuss ＋ Ni3.b near Ni when diffusion bonding temperature was 1.523.1.573.K. It was clear that Cu was a constituent in the transient liquid phase （TLP） into which Ni was dissolved by forming Cu-Ni transition liquid. Nb was dissolved in Cu-Ni transition liquid rapidly. Ti （C, N） conld be wetted by resultant Ni-Nb-Cu transient liquid phase which was followed by a little （Ti, Nb）（C, N） solid solution formed at interface. This increased the interface combining capability. Ultimately the interface shear strength was able to reach 1.0 MPa. The theoretle analysis and experimental results show that the growth of interfacial reaction layer Ni3.b accords with parabola law, and the activation energy of diffusion reaction is 1.5.0±0.5 kJ/mol, while the diffusion reaction speed constant is 1..53.mm/s^1.2.

关键词： vacuum diffusion bonding transient liquid phase (TLP) diffusion bonding interlayer activation energy

盾构隧洞斜螺栓接头在不均匀沉降作用下的受力分析

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水利水电技术(中英文) 2024年

作者：刘闯齐慧君杰德尔别克·马迪尼叶提 1.国电南京自动化股份有限公司 2.河海大学水利水电学院 3.新疆农业大学水利与土木工程学院新疆农业大学水利与土木工程学院国电南京自动化股份有限公司河海大学水利水电学院

With the construction of water transfer projects， shield tunnels have been widely used. Long distance water transfer tunnels inevitably traverse sections of poor geology and potential uneven settlement may occur in shield tunnels under non-uniform geology. As the main load-bearing structure， the current assembled outer lining mainly uses diagonal bolted joints. A reasonable modelling of the diagonal bolted joints and an analysis of their mechanical behavior under uneven settlement is of great importance for the analysis of the longitudinal stability of tunnels. In this paper， the mechanical performance of inclined bolted joints under the action of external forces is investigated. The distribution of axial force and bending moment of the inclined bolts under different operating conditions is studied， the bolts are simulated using the generalized displacement method of buried beams， and a numerical simulation method is established considering the interpolation of the corner displacement. By comparing the finite element analysis results with the test results， it is concluded that the interpolation of the corner displacement of the bolt has a significant influence on the numerical simulation， and it will generate a certain bending stress under uneven settlement， which provides a reference for engineering design.

关键词：盾构隧洞不均匀沉降装配式外衬斜螺栓受力分析

Regulation of eight avr genes by hrpG and hrpX in Xanthomonas campestris pv. campestris and their role in pathogenicity

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Progress in Natural Science:Materials International 2006年第12期16卷 1288-1294页

作者： XU Rongqi~ 1.3., LI Xianzhen~3. WEI Hongyu~3. JIANG Bole~2, LI Kai~3. HE Yongqiang~ 2,3., FENG Jiaxun~ 1.3.and TANG Jiliang~ 1.2 **(1. Guangxi Key Laboratory of Subtropical Bioresources Conservation and Utilization 2. The Key Laboratory of Ministry of Education for Microbial and Plant Genetic engineering 3. {1. of Life Science and Technology, Guangxi University, Nanning 53.004, China) Guangxi Key Laboratory of Subtropical Bioresources Conservation and Utilization Guangxi University Nanning 530004 China college of Life Science and Technology Guangxi University Nanning 530004 China The Key Laboratory of Ministry of Education for Microbial and Plant Genetic engineering Guangxi University Nanning 530004 China

Eight putative avirulence genes in Xanthomonas campestris pv. campestris (Xcc) strain 8004 were characterized by Tn5gusA5 mutagenesis and gene expression analysis. The virulence test of mutants on Chinese radish showed that all mutants in individual avr genes except avrBs2 mutant were not significantly different from the wild type in virulence. The avrBs2 mutant showed reduced virulence and bacterial growth in planta. Gene expression analysis using β-glucuronidase as reporter indicated that avrBs1.1.avrBs1.avrXccB,avrXccC,avrXccE1.were regulated by hrpG, whereas avrXccA1. avrXccA2 and avrBs2 were not. RT-PCR analysis showed that all hrpG-regulated genes except avrBs1.were also regulated by hrpX. In addition, it was demonstrated that avrBs1.was responsible for elicitation of a type III dependent hypersensitive reaction (HR) on nonhost plant pepper ECW-1.R, and wild type Xcc 8004 was unable to cause HR on pepper ECW-20R.

关键词： Xanthomonas campestris pv. campestris avirulence gene virulence expression analysis.

Digital close-range photogrammetric application to small-scale physical simulation experiment

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中国有色金属学会会刊：英文版 2011年第S3期21卷 681-685页

作者： LI Chun-yi1. CUI Xi-min2, YU Yi-ju3.1. School of Surveying and Landing Information {1., Henan Polytechnic University, Jiaozuo 454003. China 2. {1. of Geoscience and Surveying {1., China University of Mining and Technology, Beijing 1.0083. China 3. Surveying and Mapping Press, Beijing 1.0045, China [a] School of Surveying and Landing Information engineering Henan Polytechnic University Jiaozuo 454003 China [b] college of Geoscience and Surveying {1. China University of Mining and Technology Beijing 100083 China [c] Surveying and Mapping Press Beijing 100045 China

In order to research the possibility of digital close-range photogrammetric surveying in small scale physical simulation experiment, physical model coinciding with engineering practice was constructed based on similar theory. The datum processing method and surveying precision of digital close-range photogrammetric were analyzed. And the function relationship between overburden subsidence factor qr and the ratio z/H of stratum horizon z and mining depth H was researched. The results show that surveying points position mean error along horizontal direction is ±0.1.1. mm and vertical direction is ±0.1.2 mm. Therefore, multi-taking station cross direction digital close-range photogrammetric can completely satisfy the precision need of physical simulation experiment. And the empirical formula can be utilized to represent evolution law of stratum subsidence factor.

关键词： close-range photogrammetric physical simulation light-rays adjustment surveying precision subsidence factor

Key technology of mine underground mobile positioning based on LiDAR and coded sequence pattern

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中国有色金属学会会刊：英文版 2011年第S3期21卷 570-576页

作者： WANG Zhi1. 2, WU Li-xin1. 2, LI Hui-ying3.1. {1. of Resources and Civil {1., Northeastern University, Shenyang 1.0004, China 2. Academy of Disaster Reduction and Emergency Management, Ministry of Civil Affairs and Ministry of Education, Beijing Normal University, Beijing 1.0875, China 3. {1. of Computer Science and Technology, Jilin University, Changchun 1.0}01., China [a] college of Resources and Civil {1. Northeastern University Shenyang 110004 China [b] Academy of Disaster Reduction and Emergency Management Ministry of Civil Affairs and Ministry of Education Beijing Normal University Beijing 100875 China [c] college of Computer Science and Technology Jilin University Changchun 130012 China

Technologies of underground mobile positioning were proposed based on LiDAR data and coded sequence pattern landmarks for mine shafts and tunnels environment to meet the needs of fast and accurate positioning and navigation of equipments in the mine underground without satellite navigation signals. A coded sequence pattern was employed for automatic matching of 3. scans. The methods of SIFT feature, Otsu segmentation and fast hough transformation were described for the identification, positioning and interpretation of the coded sequence patterns, respectively. The POSIT model was presented for speeding up computation of the translation and rotation parameters of LiDAR point data, so as to achieve automatic 3. mapping of mine shafts and tunnels. The moving positioning experiment was applied to evaluating the accuracy of proposed pose estimation method from LiDAR scans and coded sequence pattern landmarks acquired in an indoor environment. The performance was evaluated using ground truth data of the indoor setting so as to measure derivations with six degrees of freedom.

关键词： LiDAR coded sequence pattern mobile positioning SLAM algorithm POSIT algorithm

Comparison study of trapped water in human erythrocytes by EPC and DSC method and its application

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Science China(Technological Sciences) 2004年第3期47卷 343-351页

作者： ZHAO Gang1. HE Liqun1. GUO Xiaojie2, LIU Zhong3. LUO Dawei1.3.& GAO Dayong1.3.1. Cryobiomedical engineering Research Institute, Department of Thermal Science and Energy engineering, University of Science and Technology of China, Hefei 23.027, China 2. Red Cross Blood Center of Hefei, Hefei 23.022, China 3. Department of mechanical engineering, University of Kentucky, Lexington, KY 40506-01.8, USA Univ Sci & Technol China Cryobiomed Engn Res Inst Dept Thermal Sci & Energy Engn Hefei 230027 Peoples R China Red Cross Blood Ctr Hefei Hefei 230022 Peoples R China Univ Kentucky Dept Mech Engn Lexington KY 40506 USA

The novel differential scanning calorimetry method for determining trapped water volume of human red blood cell during freezing process has been reexamined. Results show that the final erythrocyte volume is 53. of its isotonic volume after freezing to -40℃. An electronic particle counter (MultisizerTM III, Beckman Coulter Inc., USA) was used to measure cell volume changes in response to hypertonic solution. Using this approach, when extracellular solution was 3.86 mOsm, the equilibrium cell volume was found to be 57% of its isotonic value. Both results indicate that 3.%—40% of intracellular water is trapped and cannot respond to osmotic difference between intra- and extracellular solution. These findings are consistent with the published data: at least 20%—3.% of the isotonic cell water volume is retained within RBCs during freezing. Some applications of the values of trapped water are addressed.

关键词： differential scanning calorimeter/DSC, electronic particle counter/EPC, cell volumetric change, red blood cell/RBC/erythrocyte

Preparation and Enhanced Daylight-Induced Photo-Catalytic Activity of Transparent C-Doped TiO_2 Thin Films

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Journal of Wuhan University of Technology(Materials Science) 2010年第5期25卷 738-742页

作者：白爱英 college of Materials Science and {1. Taiyuan University of Technology Xin Zhou Vocational Technical college

The transparent C-doped TiO2 nanostructure films were fabricated on the silicate glass substrates by sol-gel spin-coated method. The as-prepared films were characterized by X-ray diffraction （XRD）, scanning electron microscopy （SEM）, UV-visible absorption spectra （UV-vis） and X-ray photoelectron spectroscopy （XPS）. The photocatalytic activity was evaluated via the photocatalytic oxidation of methylene blue in aqueous under daylight irradiation at room temperature. The results show that the daylight-induced photocatalytic activities of the as-prepared films are improved by the C-doping. The calcination temperatures significantly affect the morphology, microstructure and photocatalytic activity of the as-prepared samples. At 723.K, the C-doped TiO2 films exhibit the highest photocatalytic activity due to the synergetic effects of good crystallization, appropriate oxygen vacancies and strong absorption in the near UV and visible-light region.

关键词： C-doped TiO2 films daylight-induced photocatalytic activity spin-coated