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Development and Application of High Performance X80 Line Pipe for the 2.(nd) West-East Gas Pipeline

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Journal of Iron and Steel Research International 2011年第S1期18卷 39-48页

作者： LI He-lin 1., HUO Chun-yong 1., JI Ling-kang 1. {3., LI Yang 1. 3.(1. CNPC Tubular Goods Research Institute, Xi’an 71.065, China {3. . School of Material Science and Engineering, Xi’an Jiaotong university, Xi’an 71.049, China 3. School of Material Science and Engineering, university of Science and Technology {{3., {{3. {13. China) CNPC Tubular Goods Res Inst Xian 710065 Peoples R China Xi An Jiao Tong Univ Sch Mat Sci & Engn Xian 710049 Peoples R China Univ Sci & Technol beijing Sch Mat Sci & Engn Beijing 100083 Peoples R China

It is the development tendency of gas pipeline to improve strength of line pipe and transmission pressure, which is an important symbol of the progress of gas pipeline technology. The 2.d West-East Gas Pipeline (the 2.nd WEGP) is the largest-scale X80 high pressure gas pipeline project in the world. Through the joint development project by Pipeline Company, research institute, and steel company, a series of achievements of technology have been obtained, which makes it possible to apply pressure of 1.0}MPa and X80 LSAW and HSAW pipe for the 2.nd WEGP. Specifications of X80 steel and pipe have been issued based on API 5L. High performance X80 steel and pipe have been developed and meets the Specification. General design conception of applying HSAW pipe and LSAW pipe on gas transmission trunk line with large diameter and high pressure has been established. Failure control of the 2.nd WEGP has been carried out to avoid failure and reduce the lost which based on analysis of pipeline failure mode. In this paper, research and development of high performance X80 welded pipe, establishment of technical route of joint application of HSAW and LSAW steel pipe and key technology of failure control are emphatically discussed.

关键词： 2.nd WEGP acicular ferrite failure control arrest toughness strain-based design

Discovery of immune related factors in Fenneropenaeus chinensis by annotation of ESTs

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Progress in Natural Science:Materials International 2004年第1期14卷 48-55页

作者： SHEN Yaoqing 1.2. , XIANG Jianhai 1.*, WANG Bing 1.2. , LI Fuhua 1.and TONG Wei 3.1. Experimental Marine Biology Laboratory, Institute of Oceanology, Chinese Academy of Sciences, Qingdao 2.6071.China 2. Graduate School of the Chinese Academy of Sciences, beijing 1.003., China 3. Genomics & Bioinformatics Institute, Chinese Academy of Sciences, beijing 1.1.00, China) Chinese Acad Sci Inst Oceanol Expt Marine Biol Lab Qingdao 266071 Peoples R China Chinese Acad Sci Grad Sch Beijing 100039 Peoples R China Chinese Acad Sci Geonom & Bioinformat Inst Beijing 101300 Peoples R China

A total of 1.446 expressed sequence tags (ESTs) are obtained by a large scale sequencing of a cDNA library from cephalothorax of adult Fenneropenaeus chinensis . An EST analysis platform was built up based on local computers and bioinformatic techniques were used to annotate these ESTs in order to promptly find possible functional genes, especially for immune related factors. About 4% of the ESTs show similarity to the coding sequences of such factors, including lectin, serine protease, serpin, lysozyme, etc. These ESTs provide a partial profile of the immune system in F. chinensis and useful information for further study on these genes.

关键词： Fenneropenaeus chinensis bioinformatics ESTs immune factors

北京市规划和自然资源委员会北京市发展和改革委员会关于办理本市批次用地农用地转用和土地征收事项与立项文件衔接有关事宜的通知(试行)

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北京市人民政府公报 2024年第22期 8-9页

作者： 1.北京市规划和自然资源委员会 2.北京市发展和改革委员会北京市规划和自然资源委员会北京市发展和改革委员会

京规自发〔2.2.〕1.号各区人民政府、城市副中心管委会、北京经济技术开发区管委会、大兴国际机场临空经济区(大兴)管委会:为进一步优化我市营商环境,缩短用地要素供应周期,依据《土地管理法》《土地管理法实施条例》及国家、北京市建...

京规自发〔2.2.〕1.号各区人民政府、城市副中心管委会、北京经济技术开发区管委会、大兴国际机场临空经济区(大兴)管委会:为进一步优化我市营商环境,缩短用地要素供应周期,依据《土地管理法》《土地管理法实施条例》及国家、北京市建设项目投资管理相关规定,结合我市实际,经请示市政府同意,现就办理批次用地农用地转用和土地征收事项与立项文件衔接有关事宜通知如下:一、成片开发类项目用地(土地一级开发、棚户区改造及环境整治、工业用地前期开发等项目)

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Approximation of dense-n/2.subgraph and table compression problems

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Science China Mathematics 2005年第9期48卷 1223-1233页

作者： XU Dachuan~1.HAN Jiye~2.& DU Dongle~3.1. College of Applied Sciences,{1. university of Technology,{1. 1.002.,China 2. Institute of Applied Mathematics,Academy of Mathematics and Systems Science,Chinese Academy of Sciences,{1. 1.0080,China 3. Faculty of Administration,university of New Brunswick,P.O.Box 4400,Fredericton,NB E3. 5A3.Canada College of Applied Sciences Beijing University of Technology Beijing 100022 China Institute of Applied Mathematics Academy of Mathematics and Systems Science Chinese Academy of Sciences Beijing 100080 China Faculty of Administration University of New Brunswick P.O. Box 4400 Fredericton NB E3B 5A3 Canada

We develop improved approximation algorithms for two NP-hard problems: the dense-n/2.subgraph and table *** on SDP relaxation and advanced rounding techniques,we first propose 0. 5982.and 0. 5970-approximation algorithms respec- tively for the dense-n/2.subgraph problem (DSP) and the table compression problem (TCP). Then we improve these bounds to 0. 62.3.and 0. 6708 respectively for DSP and TCP by adding triangle inequalities to strengthen the SDP *** results for TCP beat the 0. 5 bound of a simple greedy algorithm on this problem,and hence answer an open question of Anderson in an affirmative way.

关键词： dense-n/2.subgraph problem(DSP) table compression problem(TCP) SDP approximation ratio

Stress distribution rule of roadway affected by overhead mining in gently inclined coal seams group

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中国有色金属学会会刊：英文版 2011年第S3期21卷 529-535页

作者： KANG Qin-rong1. 2. TANG Jian-xin1. 2. HU Hai1. 2. ZHANG Wei-zhong1. 3.1. College of Resource and Environmental Sciences, Chongqing university, Chongqing 40003., China 2. State Key Laboratory of Coal Mine Disaster Dynamics and Control, Chongqing university, Chongqing 40003., China 3. School of Safety Science and Administration, Zhongnan university of Economics and Law, Wuhan 43.074, China College of Resource and Environmental Sciences Chongqing University Chongqing 400030 China State Key Laboratory of Coal Mine Disaster Dynamics and Control Chongqing University Chongqing 400030 China School of Safety Science and Administration Zhongnan University of Economics and Law Wuhan 430074 China

In light of the severe deformation and destruction of the district raise tunnel in the mining area at the northern part of the Lubanshan colliery, by the theoretic analysis and numerical simulation, both the mining stress distribution in seams group and the deformation and destruction mechanism of floor district raise were investigated. The results show that, at the maximum vertical distance of 40 m, the abutment stress has an influence on the recovery of 2. and 3. coal seam and 8# coal seam at distance of 3. m. As a result, the recovery of 8# is rather than those of 2. or 3. coal seam, which contributes to the deformation and destruction of the district raise surrounding rock. The major factors affecting the abutment stress include the mining depth, mining height, residual gob space, adjacent working faces and short spacing coal seam recovery.

关键词： coal seams group stress distribution district raise surrounding rock deformation and destruction abutment stress

Spatiotemporal model of open-pit based on 3.D deposit model

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中国有色金属学会会刊：英文版 2011年第S3期21卷 616-620页

作者： XIA Chun-lin1. ZHOU Hui1. LI Qing-yuan2. MA Zhen-li3.1. School of {1.matics, Liaoning Technical university, Fuxin 1.0}000, China 2. State Key Laboratory for GIS Engineering, Chinese Academy of Surveying and Mapping, {2. 1.083., China 3. Yinchuan College, China university of Mining and Technology, Yinchuan 75001., China School of geomatics Liaoning Technical University Fuxin 123000 China State Key Laboratory for GIS Engineering Chinese Academy of Surveying and Mapping Beijing 100830 China Yinchuan College China University of Mining and Technology Yinchuan 750011 China

A new method was put forward to make up the three-dimensional deposit model, and the spatiotemporal models of open-pit with temporal dynamics were also studied combined with the corrected models of multilevel ground states so as to bring the three-dimensional open-pit model at different time and its model serial formed from the evolvement into the management of temporal dimension in order to realize the spatial three-dimension and temporal dynamic for the mining management in open-pits,which makes this model easy to query and analyze 3.D information, also help surface mining replaying and stope evolution forecasting. Finally, the time-spatial model was established to show the dynamic mining on some open-pit under the windows XP and VC++ environment.

关键词： 3. model of deposit three-dimensional model mixed model temporal model open-pit

Analysis on cohesive crack opening displacement considering the strain softening effect

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Science China(Physics,Mechanics & Astronomy) 2006年第1期49卷 88-101页

作者： WANG Limin1. XU Shilang2.& ZHAO Xiqiang3.1. Mechanics Department, Shandong {1. of Technology, Zibo 2.5049, China 2. Civil Engineering Department, Dalian {1. of Technology, Dalian 1.602., China 3. Mathematics Department, Ocean {1. of China, Qingdao 2.6071. China Mechanics Department Shandong University of Technology Zibo China Civil Engineering Department Dalian University of Technology Dalian China Mathematics Department Ocean University of China Qingdao China

In order to investigate the crack propagation in quasi-brittle materials like rock, ceramic and concrete, Hillerborg and his co-researchers abstracted the fracture process zone in front of a stress free crack in terms of a “fictitious crack zone”. On the fictitious crack zone, cohesive stresses distribute following a given softening relationship of stress vs. crack opening. Based on the polynomial or power series expression of cohesive crack opening displacement, the relationship of the cohesive stress vs. the crack opening displacement is established using elastic theory and integral equation, and some unknown physics variables are obtained using variation approach. The calculation results gained in this paper are close to the experimentally test ones.

关键词： cohesive crack, softening, dissipation work, variation approach.

Human remains and the environment of Early Pleistocene in the Nihewan Basin

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Science China Earth Sciences 2004年第5期47卷 437-444页

作者： CAI Baoquan1.& LI Qiang2.1. Department of History, Xiamen {1., Fujian 3.1.05, China 2. Institute of Vertebrate Palaeontology and Palaeoanthropology, Chinese Academy of Sciences, beijing 1.0044, China Department of History Xiamen University Fujian 361005 China Inst. of Vertebrate Palaeontology Chinese Academy of Sciences Beijing 100044 China

A new Early Pleistocene Paleolithic site was found in July 2.01.in the Nihewan Ba-sin, Hebei Province. Totally 500 mammal specimens assigned to 2. species and 5 lithic artifacts were collected. The coexistence of Allophaiomys deucalion, Borsodia chinensis and Yangia tingi provides important evidence of chronology. On the basis of the comparison of mammalian fauna, the date of Paleolithic artifacts is probably earlier than 1.8 MaBP, possibly 2.0 MaBP. This is the earliest evidence of hominid activity found so far in North China. The hominid at that time in the Nihewan Basin lived in an environment of arid grasslands with scattered trees of temperate zone. This discovery is significant to the study of human origin and cultural development.

关键词： human remains, environment, Early Pleistocene, Nihewan.

Petrogenesis of Songshugou dunite body in the Qinling orogenic belt, Central China: Constraints from geochemistry and melt inclusions

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Science China Earth Sciences 2005年第8期48卷 1146-1157页

作者： SU Li1.2. SONG Shuguang3.& ZHOU Dingwu1.1. Key Laboratory of Continental Dynamics of the Ministry of Education, Department of {1.logy, Northwestern university, Xi’an 71.069, China 2. The {1.logical Lab Center, China university of {1.sciences (beijing), beijing {13. China 3. Key Laboratory of Orogenic Belts of the Ministry of Education, Department of {1.logy, Peking university, beijing 1.0871. China Key Laboratory of Continental Dynamics of the Ministry of Education Department of Geology Northwestern University Xi’an China The geological Lab Center China University of Geosciences (Beijing)Beijing China Key Laboratory of Orogenic Belts of the Ministry of Education Department of Geology Peking University Beijing China

The Songshugou dunite body, which occupies an area of about 2. km2. is the largest ultramafic massif in the eastern Qinling orogenic belt, Central China. The major compo-nent of this body is dunitic rocks including mylonitic dunite and coarse-grained dunite; they oc-cupy about 95 vol% of the total body. Petrography, mineral composition, major and trace ele-ments and primitive melt inclusions have been investigated in this paper; all revealed that this dunite body is the product of melt-rock interaction by porous percolation flow. In comparison with dunite sills or veins in harzburgite from the basal part of Oman ophiolite, this dunite body is characterized by lower contents of Al2.3. CaO and HREE but higher content of highly incom-patible elements and Zr and Hf. The LREE enriched patterns and primitive mantle normalized spidergrams of trace elements are also different from the Oman dunite. Combining with melt in-clusions observed in olivines, we conclude that this dunite body is the product of large- scale porous percolation flow of high-MgO melts within depleted mantle peridotites. The high-MgO magma, in essence, was most probably produced at the hot head of an upwelling mantle plume. The occurrence of the Songshugou dunite body is closely associated with the activity of mantle super-plume in Neo-Proterozoic era in the Yangtze Craton.

关键词： Songshugou dunite body, geochemistry, melt inclusion, mantle plume, Qinling orogenic belt.