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Direct Current Electric Arc-Electroslag Ladle Furnace

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Journal of university of science and technology beijing 2001年第2期8卷 98-100页

作者： Ping Wang, Jie Fu, Minsheng sun, Xiangmao Kong, Zhimin Ma, Meilun shi, Xingjiang Wang (Metallurgy school, university of science and technology beijing, beijing 100083, china) (Machinery Engineering school, university of science and technology beijing, Be Univ sci & Technol beijing Met Sch Beijing 100083 Peoples R China Univ sci & Technol beijing Machinery Engn Sch Beijing 100083 Peoples R China Anyang Iron & steel Grp Co Ltd Anyang 455004 Peoples R China

In order to solve the high consumption problem of small capacity ladle furnace (LF), the operation principle and control method of the DC are and electroslag heating ladle furnace are introduced. With only one arcing electrode, the distance between the are and the wall of ladle is enlarged, and consequently the consumption of the ladle refractory is decreased. In the invention, a signal electrode is embedded in the refractory lining of the ladle, which contacts directly with the liquid steel and the ladle shell. Two graphite anode ends are submerged in the slag layer. The signal electrode is used as voltage reference during refining process. The electroslag voltage between anode end and liquid steel is applied to control the depth of anode end in the slag layer during the refining process with this ladle furnace.

关键词： ladle furnace secondary refining DC electroslag

Full-scale experimental research on fire fume refluence of sloped long and large curved tunnel

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science china(Technological sciences) 2011年第S1期54卷 89-94页

作者： ZHONG MaoHua 1,shi CongLing 1,HE Li 1,shi JieHong 1 & FU TaiRan 2 1 china academy of safety science and technology,beijing 100012,china 2 Key Laboratory for Thermal science and Power Engineering of Ministry of Education,Department of Thermal Engineering,Tsinghua university,beijing 100084,china 1. china academy of safety science and technology Beijing 100012 China 2. Key Laboratory for Thermal science and Power Engineering of Ministry of Education Department of Thermal Engineering Tsinghua University Beijing 100084 China

A full-scale experimental research is conducted on the fire fume refluence of a sloped long and large curved tunnel in the underground plant of a hydraulic and hydropower engineering project under three different fire *** a result,the eddy effect and pattern of the fire fume flow in the tunnel in case of fire is discovered and the refluence of the fume layers in case of fire is *** analysis of the temperature measurement resulted in the course of the experiment,the main characteristics and performance of the fire fume refluence are discussed under the three different fire powers.

关键词： large and long tunnel fire fume refluence experiment

A computational model for feature binding

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science china(Life sciences) 2008年第5期51卷 470-478页

作者： shi ZhiWei1,2, shi ZhongZhi1, LIU Xi1,2 & shi ZhiPing1 1 Key Laboratory of Intelligent Information Processing, Institute of Computing technology, chinese academy of sciences, beijing 100190, china 2 Graduate university of chinese academy of sciences, beijing 100049, china Key Laboratory of Intelligent Information Processing Institute of Computing Technology Chinese Academy of Sciences Beijing 100190 China Graduate university of chinese academy of sciences Beijing 100049 China

The "Binding Problem" is an important problem across many disciplines, including psychology, neuroscience, computational modeling, and even philosophy. In this work, we proposed a novel computational model, Bayesian Linking Field Model, for feature binding in visual perception, by combining the idea of noisy neuron model, Bayesian method, Linking Field Network and competitive mechanism. simulation Experiments demonstrated that our model perfectly fulfilled the task of feature binding in visual perception and provided us some enlightening idea for future research.

关键词： Binding Problem computational model Bayesian Linking Field Model

Association of physical activity with risk of chronic kidney disease in china:A population-based cohort study

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Journal of sport and Health science 2024年第2期13卷 204-211页

作者： Kexiang shi Yunqing Zhu Jun Lv Dianjianyi sun Pei Pei Huaidong Du Yiping Chen Ling Yang Bing Han Rebecca stevens Junshi Chen Zhengming Chen Liming Li Canqing Yu china Kadoorie Biobank collaborative group Department of Epidemiology&Biostatistics School of Public HealthPeking University Health Science CenterBeijing 100191China Peking university Center for Public Health and Epidemic Preparedness&Response Beijing 100191China Key Laboratory of Epidemiology of Major Diseases(Peking university) Ministry of EducationBeijing 100191China Clinical Trial service Unit&Epidemiological studies Unit(CTsU) Nuffield Department of Population HealthUniversity of OxfordOxford OX37LFUK Medical Research Council Population Health Research Unit at the university of Oxford Oxford OX37LFUK NCDs Prevention and Control Department Henan Center for Disease Control and PreventionZhengzhou 450016China china National Center for Food safety Risk Assessment Beijing 100022China 不详

Background:Information on the association between physical activity(PA)and the risk of chronic kidney disease(CKD)is *** aimed to explore the associations of total,domain-specific,and intensity-specific PA with CKD and its subtypes in ***:The study included 475,376 adults from the china Kadoorie Biobank aged 30-79 years during 2004-2008 at *** interviewer-administered questionnaire was used to collect the information about PA,which was quantified as metabolic equivalent of task hours per day(MET-h/day)and categorized into 4 groups based on *** regression was used to analyze the association between PA and CKD ***:During a median follow-up of 12.1 years,5415 incident CKD cases were documented,including 1159 incident diabetic kidney disease(DKD)cases and 362 incident hypertensive nephropathy(HTN)*** PA was inversely associated with CKD risk,with an adjusted hazard ratio(HR,95%confidence interval(95%CI))of 0.83(0.75-0.92)for incident CKD in the highest quartile of total PA as compared with participants in the lowest *** results were observed for risk of DKD and HTN,and the corresponding HRs(95%CIs)were 0.75(0.58-0.97)for DKD risk and 0.56(0.37-0.85)for HTN *** nonoccupational PA,low-intensity PA,and moderate-to-vigorous-intensity PA were significantly associated with a decreased risk of CKD,with HRs(95%CIs)of 0.80(0.73-0.88),0.85(0.77-0.94),and 0.85(0.76-0.95)in the highest quartile,***:PA,including nonoccupational PA,low-intensity PA,and moderate-to-vigorous-intensity PA,was inversely associated with the risk of CKD,including DKD,HTN,and other CKD,and such associations were dose dependent.

关键词： Chronic kidney disease Domain Intensity Physical activity

Monitoring the concentration of N_2O in the Fildes Peninsula, maritime Antarctica

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chinese science Bulletin 2000年第21期45卷 2000-2004页

作者： sUN Liguang, XIE Zhouqing, ZHAO Junlin, XING Guangxi, shi shulian & Du LijuanInstitute of Polar Environment, university of science and technology of china, Hefei 230026, china Institute of Environmental science, beijing Normal university, beijing 100875, china Laboratory of Material Cycling in Pedosphere, Institute of soil science, chinese academy of sciences, Nanjing 2 10008, china Institute of Polar Environment University of Science and Technology of China Hefei China Institute of Environmental science Beijing Normal University Beijing China Laboratory of Material Cycling in Pedosphere Institute of Soil Science Chinese Academy of Sciences Nanjing China

Gases in the marine boundary layer in Fildes Peninsula, maritime Antarctica were sampled and analyzed for the first time. sampling sites included areas covered by moss and lichen growth, penguin colonies and an area where scientific research stations are located. A total of 211 samples were analyzed for N2O concentrations, with an average of (321.33±3.07) nL/L. This is above the global average value of 314 nL/L. It is found that the N2O concentrations evidently increase during the summer months. Concentrations around the research stations are higher than at remote areas, indicating a potential source from human activities on the island. N2O concentrations at a large penguin colony on Barton Peninsula are the highest among the sampled areas. This may explain why N2O concentrations in Fildes Peninsula are higher than the global average. Our preliminary conclusions are that human activities and emissions from penguin dropping-amended soil and vegetation soil constitute the major sources of N2O in the

关键词： Antarctica Fildes Peninsula N2O soil penguin dropping.

study on the atmospheric photochemical reaction of CF_3 radicals using ultraviolet photoelectron and photoionization mass spectrometer

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science china Chemistry 2008年第4期51卷 316-321页

作者： YAO Li1,2, DU Lin1,2, YIN shi1,2 & GE MaoFa1 1 beijing National Laboratory for Molecular {2.s (BNLMs), state Key Laboratory for structural Chemistry of Unstable and stable species, Institute of Chemistry, chinese academy of {2.s, beijing 100080, china 2 Graduate university of chinese academy of {2.s, beijing 100080, china 1. beijing National Laboratory for Molecular sciences (BNLMs) State Key Laboratory for Structural Chemistry of Unstable and Stable Species Institute of Chemistry Chinese Academy of Sciences Beijing 100080 China 2. Graduate university of chinese academy of sciences Beijing 100080 China

A study of the atmospheric photochemical reaction of CF3 radical with CO and O2 was performed by using a homemade ultraviolet photoelectron spectrometer-photoionization mass spectrometer (PEs- PIMs). The electronic structures and mechanism of ionization and dissociation of CF3OC(O)OOC(O)- OCF3 were investigated. It was indicated that the two bands on the photoelectron spectrum of CF3OC(O)OOC(O)OCF3 are the result of ionization of an electron from a lone pair of oxygen and a fluo- rine lone pair of CF3 group. The outermost electrons reside in the oxygen lone pair. The experimental and theoretical first vertical ionization energy is 13.21 and 13.178 eV, respectively, with the PEs and OVGF method. They are in good agreement. The photo ionization and dissociation processes were discussed with the help of theoretical calculations and PEs-PIMs experiment. After ionization, the parent ions prefer the dissociation of the C-O bond and giving the fragments CF3OCO+ and CF3+. It demonstrated that the ultraviolet photoelectron and photoionization mass spectrometer could be ap- plied widely in the study of atmospheric photochemical reaction.

关键词： photochemical reaction CF3 radical ultraviolet photoelectron and photoionization mass spectroscopy transient species

suitability evaluation for land reclamation in mining area:A case study of Gaoqiao bauxite mine

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中国有色金属学会会刊：英文版 2011年第S3期21卷 506-515页

作者： WANG shi-dong1, 2, LIU Chang-hua2, ZHANG He-bing2 1. College of Resources science and technology, beijing Normal university, beijing 100875, china 2. school of surveying and Land Information Engineering, Henan Polytechnic university, Jiaozuo 454000, china [a] College of Resources science and technology Beijing Normal University Beijing 100875 China [b] school of surveying and Land Information Engineering Henan Polytechnic University Jiaozuo 454000 China

suitability evaluation plays an important role in land reclamation because the choice of evaluation methods affects the accuracy and objectivity of the suitability evaluation results. Furthermore, it influences the decision-making related to land reclamation. An improved method, which is called limit comprehensive conditions method, was developed after different suitability evaluation methods were studied. Based on this method, the reclaimed land of the Gaoqiao bauxite mining area was evaluated. The Gaoqiao mining area was divided into seven evaluation units that were evaluated respectively by selecting evaluation factors and establishing grade standards. The results show that the proposed method is more applicable and easier to handle. Moreover, its evaluation results are more scientific compared with the traditional evaluation methods. The improved method can be beneficial to the rapid monitoring and the effective management of reclaimed land in the opencast mine area.

关键词： mining area land reclamation suitability evaluation Gaoqiao bauxite mine

services Discovery for Distributed Network Measurement

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计算机工程 2002年第S1期28卷 28-32页

作者： LI Wei, QIAN DepeiLI Yunchun, shi Nayan(Dept. of Computer science &technology,beijing university of Aeronautics &Astronautics,beijing 100083,china) Dept. of Computer science &technology Beijing University of Aeronautics &AstronauticsBeijing 100083China

More and more distributed applications are deployed around interconnected network, which makes it necessary for network measurement services to address the scalability and robustness requirements. This paper discusses a service discovery forintegrated network measurement architecture (INMA), including finding the location of measurement agent, the path of the measurement and the network attributes of the end-to-end path or host. It also describes the functions of the major building blocks used to construct the measurement architecture.

关键词： service discovery Network measurement Directory server

Friction and wear properties of copper matrix composites reinforced by tungsten-coated carbon nanotubes

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Rare Metals 2011年第6期30卷 657-663页

作者： NIE Junhui JIA Xian JIA Chengchang LI Yi ZHANG Yafeng shi Na school of Materials science and Engineering University of Science and Technology Beijing Beijing 100083 China china Iron ＆ steel Research Institute Group Beijing 100081 China Journals Publishing Center University of Science and Technology Beijing Beijing 100083 China

Carbon nanotubes （CNTs） were coated by tungsten layer using metal organic chemical vapor deposition process with tungsten hexacarbonyl as a precursor. The W-coated CNTs （W-CNTs） were dispersed into Cu powders by magnetic stirring process and then the mixed powders were consolidated by spark plasma sintering to fabricate W-CNTs/Cu composites. The CNTs/Cu composites were fabricated using the similafprocesses. The friction coefficient and mass wear loss of W-CNTs/Cu and CNTs/Cu composites were studied. The results showed that the W-CNT content, interfacial bonding situation, and applied load could influence the friction coefficient and wear loss of W-CNTs/Cu com- posites. When the W-CNT content was 1.0 wt.%, the W-CNTs/Cu composites got the minimum friction coefficient and wear loss, which were decreased by 72.1% and 47.6%, respectively, compared with pure Cu specimen. The friction coefficient and wear loss of W-CNTs/Cu composites were lower than those of CNTs/Cu composites, which was due to that the interracial bonding at （W-CNTs）-Cu interface was better than that at CNTs-Cu interface. The friction coefficient of composites did not vary obviously with increasing applied load, while the wear loss of composites increased significantly with the increase of applied load.

关键词： carbon nanotubes tungsten layer copper friction coefficient wear loss