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Theoretical analysis and applications of Y-Inversion Ventilation System in a mine fire zone

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Mining Science and Technology 2010年第5期20卷 672-676页

作者： YANG Shengqlang PANG Weidong WEN Hu YU Baohua MA Zhihe HUANG Ruiling State Key Laboratory of Coal Resources and Mine Safety School of Safety and Engineering China University of Mining & Technology Xuzhou 221008 China china national machinery import & export corporation Beijing 100037 China School of Safety and Engineering Xi 'an University of Science and Technology Xi'an 710054 China Xuzhou Mining Group Xuzhou 221000 China

Based on mine fire fighting practices at the 1110 working face of the Brapukuria Coal Mine,Bangladesh,we introduce and discuss the Y-Inversion Ventilation System,the latest technology used both in mine fire zone management and the unsealing *** ventilation system can ensure that all miners breathed fresh air,providing protection for them during fire fighting and unsealing the fire *** the other hand,adjusting the amount of air at the working face and forming a CO leakage path controlled the state of the fire and as well ensured that the different fire extinguishing measures could be applied *** are all fundamental techniques which ensured successful fire extinguishing and unsealing of the fire *** also analyzed the main reasons for the spontaneous coal combustion that occurred at the 1110 working *** application of advanced composite polymer colloidal perfusion techniques,polymer foam MEA perfusion and fire-prevention technology by infusing nitrogen,used in mine fire zone management and unsealing,are *** value the experience with these techniques very highly and are of the opinion that these techniques could be widely used in mine fire fighting practices under similar spontaneous coal combustion conditions elsewhere.

关键词： Brapukuria Coal Mine coal mine fire zone management Y-Inversion Ventilation System

The application of digital technology in BEPCII RF system

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Radiation Detection Technology and Methods 2018年第1期2卷 105-112页

作者： Mu-Yuan Wang Yi Sun Guang-Wei Wang Wei-Min Pan Hai-Ying Lin Qun-Yao Wang Qiang Ma Zhong-Quan Li Jian-Ping Dai Peng Sha Zheng-Hui Mi Hong-Lei Wang Dan-Yang Zhao University of Chinese Academy of Sciences Beijing 100049China Institute of High Energy Physics CASBeijing 100049China china national Electronics import&export corporation(CEIEC) BeijingChina

Background The Beijing Electron Positron Collider(BEPCII)is a high-brightness collider and operates in compatible mode of synchronous light *** summer,BEPCII spare cavity,which was all made in china,had been put into BEPCII operation,and the LLRF system for the spare cavity was also upgraded at the *** The purpose is to stably control the amplitude and phase of the spare cavity and apply digital technology to achieve some intelligent *** The digital method is applied in the superconducting cavity feedback control of the accelerator and it introduces the digital technology of the RF low-level control system that has been stably applied to the BEPCII spare cavity *** addition,some functions such as quench detector and input protection as well as horizontal test have been realized in the RF system *** The amplitude and phase stabilities of cavity voltage with beam in the digital LLRF have reached±0.09%(RMS)and±0.055°(RMS),*** The BEPCII spare cavity with digital LLRF system has been stably operated for 2 *** DLLRF system has been reliable and stable,and the performance of the spare cavity with beam was very good.

关键词： Digital low-level Radio frequency Spare cavity

Effect of VC and NbC additions on microstructure and properties of ultrafine WC-10Co cemented carbides

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中国有色金属学会会刊：英文版 2009年第6期19卷 1520-1525页

作者：肖代红贺跃辉罗伟红宋旼 State Key Laboratory of Powder Metallurgy Central South University Hunan import and export Company of Chinese Automobile Industry

The nanocomposite WC-Co powders were prepared through planetary ball milling *** of grain growth inhibitor addition and the vacuum sintering parameters on the microstructure and properties of ultrafine WC-10Co cemented carbides were investigated using X-ray diffractometer,scanning electron microscope and mechanical property *** results show that VC and NbC additions can refine the WC grains,decrease the volume fraction of Co3W3C phase in ultrafine WC-10Co cemented carbides,and increase the hardness and fracture toughness of the base *** sintering for 60 min at 1 400℃,the average grain size and hardness of ultrafine-grained WC-10Co-1VC cemented carbide are 470 nm and HRA 91.5,*** fracture toughness of cemented carbide WC-10Co-1NbC alloy is over 7 MN·m -3/2 .

关键词：纳米硬质合金性能测试仪微观结构风险投资 WC相超细碳化铌 X射线衍射仪

With Belt and Road Vitality, export to Main tain Growth Momentum

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船舶经济贸易 2019年第4期 68-70页

作者：无 Shipbuilding Branch of china Chamber of Commerce for import and export of machinery and Electronic Products

china ship export achieved good performance in 2018 as a result of great efforts of the national shipbuilding industry with strong support of various national policies and nirasures of stabilize foreign trade. china s... 详细信息

关键词： china ship export result of great efforts foreign trade

柳珊瑚酸钠对豚鼠离体工作心脏及其缺血再灌注血流动力学的影响(英文)

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中国药理学报 1995年第3期16卷 285-288页

作者：许实波彭汶铎胡宇彤中山大学生物系药理室 Guangzhou Medicines and Health Products import & export corporation Guangzhou 510181 China

目的:研究柳珊瑚酸钠(suberogorgin,Sub)对正常和缺血再灌注损伤工作心脏的作用.方法:用含edetic acid 0.2 μmol·L^(-1)的克-亨氏液(37±0.5 C)从左肺静脉对心脏进行灌注.左房灌注压和左室负荷分别为1.0和7.2kPa,50 min低流缺血期间,... 详细信息

目的:研究柳珊瑚酸钠(suberogorgin,Sub)对正常和缺血再灌注损伤工作心脏的作用.方法:用含edetic acid 0.2 μmol·L^(-1)的克-亨氏液(37±0.5 C)从左肺静脉对心脏进行灌注.左房灌注压和左室负荷分别为1.0和7.2kPa,50 min低流缺血期间,冠脉流量为正常灌注时的4.7±0.2％,此后进行35 min的再灌注.结果:Sub 10 μmol·L^(-1)使正常工作心脏的AP,LVSP,+dp/dt_(max),-dp/dt_(max),CO和SV分别提高14％,17％,17％,22％,15％和32％,但使LVEDP和HR各下降200％和11％;Sub 50 μmol·L^(-1)则降低上述指标.对于缺血再灌注损伤的心脏,Sub 10 μmol·L-1使除HR外的上述指标恢复至缺血前水平,而Sub 50 μmol·L^(-1)仅使这些指标部分恢复.结论:Sub对心肌缺血再灌注损伤有明显的保护作用.

关键词：柳珊瑚酸心脏心肌再灌注损伤血液动力学

Effects of Vertical Irregularity in Steel Braced Frames on Response to Earthquake

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Journal of Civil Engineering and Architecture 2018年第2期12卷 106-112页

作者： Md.Mahmud Sazzad Gazi Md.Sharfaraz Imam Azad Md.SamdaniAzad Niloy Samadder Department of Civil Engineering Rajshahi University of Engineering&TechnologyRajshahi6204Bangladesh Department of Civil&Environmental Engineering Faculty of EngineeringMahidol UniversityThailand china national machinery import&export corporation(CMC) Beijing100037China

This paper deals with the irregular profile of braced steel frame building in vertical direction with shear link bracing *** underlying fact of the paper is the effect of seismic force in braced frames with different types of irregularities including mass irregularity,mass discontinuity and overhanging *** each successive model,the position of shear link bracings has been fixed to make the study *** study has investigated the vulnerable effect of irregular profiles in steel frame *** attain the behavior of each frame,linear time history analysis method has been adopted for the present ***356 standard has been used here for linear time history *** on different frames exhibit that regular profile with symmetry in mass is more efficient while using overhanging mass is detrimental considering the time dependent displacements and accelerations.

关键词： Steel frame shear link time history analysis irregular profile.

Risks and Firms' Decision Making on Outward Foreign Direct Investment: An Empirical Analysis of china's State-owned Enterprises

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china & World Economy 2022年第6期30卷 163-182页

作者： Xiaosong Wang Huan Wu Le Li School of Economics Renmin University of ChinaChina Post-doctoral Workstation of china export and Credit Insurance corporation China china Bohai Bank China

This study explored how the risks encountered by Chinese state-owned enterprises(SOEs)affected their decision-making on outward foreign direct investment(OFDI),using data regarding the relationship between the host countries and *** following conclusions were *** SOEs with fixed capital exhibited a higher probability of conducting OFDI and did so on a larger *** risks in host countries significantly hindered the OFDI of Chinese *** pursuit of natural resources,Chinese SOEs chose to take *** amount of OFDI by SOEs was positively related to the political,economic,and geographical relations between china and the corresponding hostcountry.

关键词： bilateral relations OFDI risks SOEs

Wildlife export Quota and Its Administrative System

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Journal of Forestry Research 1998年第2期9卷 95-101页

作者：孟宪林马建章陈化鹏常弘高二虎温战强 Administrative Office for Endangered Species of Wild Fauna and Flora import and export Beijing P.R. China College of Wildlife Resources Northeast Forestry University China Department of Biology Zhongshan University Zhongshan China Monitoring Centre of Environment and Wildlife National Forestry Agency China

The authors discussed the administrative system of export quota and its method of calculation in the international wildlife trade. Three methods for determining wildlife export quota in china was put forvvard, based on the trend and status, domestic use, and historical export of wildlife resources. They include the single factor method, the double factor method, and the multiple faCtor method. In addition, the approaches and measures to establish and carry out the administrative system of wildlife export quota in china were discussed in this paper.

关键词： export quota International wildlife trade Administrative system of wildlife export

Oil and gas cooperation between china and Central Asia in an environment of political and resource competition

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Petroleum Science 2014年第4期11卷 596-605页

作者： Hu Bin College of Petroleum Engineering China University of Petroleum Beijing The Planning Department China National Petroleum Corporation (CNPC)

This paper investigates Central Asia＇s oil and gas resources, special geopolitics and energy competition, and approaches, challenges and prospects in cooperation between china and Central Asia. The objective is to propose measures for oil and gas cooperation between china and Central Asia. Central Asia is rich in oil and gas resources. Its remaining recoverable reserves of crude oil and natural gas account for 1.9% and 10.6 %, respectively, of the world＇s total reserves. Moreover, there is great exploration and development potential. As a strategic channel connecting Eurasia, Central Asia has a prominent geopolitical status. Many powerful countries such as the United States, Russia and china, as well as Europe, have an intense energy competition in Central Asia. In the oil and gas cooperation with Central Asia, the china national Petroleum corporation （CNPC） focuses on establishing a coordination group, promoting overall oil and gas business opportunities and sustainable development, innovating and applying specialty engineering technology and improving project economic benefits. Through its efforts over the last nearly two decades, the china national Petroleum corporation has completed a 50-million-tonne a year oil and gas production centre in Central Asia and oil and gas pipelines passing through multiple countries, becoming an important channel for securing china＇s energy imports. If appropriate measures are taken in the ＇Thirteenth Five-Year Plan＇ period or later, the china national Petroleum corporation will develop a 100-million-tonne p.a. oil and gas production centre in Central Asia and a strategic oil and gas import channel exceeding this amount of production. This cooperation between china and Central Asia is however faced with the following challenges： increasing multinational competition uncertainty, potential risks in the political systems of Central Asian countries, frequently occurring violence and also resource policy tightening in Central Asia. To f

关键词： Central Asia oil and gas cooperation competition energy channels oil and gas productioncentre mode innovation proposal