检索结果-南通市图书馆

Properties and applications of cold supersonic gas jet

在线全文

学校读者我要写书评

暂无评论

Science china(Physics,Mechanics & Astronomy) 2006年第6期49卷 709-715页

作者： ZHANG Shaofeng1,2.MA Xinwen1,2.LIU Huiping2.LI Bin1,2.& ZHU Xiaolong1,2.1. Institute of Modern Physics,chinese academy of {2.,Lanzhou 730000,china 2. graduate University of chinese academy of {2.,beijing 100049,china Institute of Modern Physics Chinese Academy of Sciences Lanzhou China graduate University of chinese {2. of sciences Beijing China

By analyzing the formation mechanism of a supersonic gas jet,a set of equations which describe the atomic beam properties were established. The influence of initial temperature,initial pressure,background gas pressure and pumping speed was discussed in detail. A simulation program was developed based on the equations,and the results under different initial conditions were obtained. The results are in good agreement with the experimental data,and suggest that,in order to get much smaller transverse momentum in collision experiments,it is necessary to lower the initial temperature and the initial pressure of the supersonic gas jet,together with increasing the pumping speed. These results are very instructive for construction of a new generation of cold supersonic gas jets.

关键词： cold supersonic gas jet,zone of silence,nozzle,skimmer.

Effects of the grain size distribution on the temperature-dependent magnetic susceptibility of magnetite nanoparticles

在线全文

学校读者我要写书评

暂无评论

Science china Earth sciences 2010年第7期53卷 1071-1078页

作者： ZHAO XiangYu1,2.& LIU QingSong1 1 Paleomagnetism and Geochronology Laboratory (SKL-LE), Institute of Geology and Geophysics, chinese academy of {2., beijing 10002., china 2.graduate University of chinese academy of {2., beijing 100049, china Paleomagnetism and Geochronology Laboratory (SKL-LE) Institute of Geology and Geophysics Chinese Academy of Sciences Beijing China graduate University of chinese {2. of sciences Beijing China

Magnetite is an important magnetic remanence carrier in natural samples and therefore is of great interest in paleo-, rock-, and environmental magnetism. The magnetic properties of magnetite depend on many factors, e.g., concentration and grain size distribution (GSD). In this study, we theoretically investigated the temperature-dependent susceptibility (TDS) of magnetite nanoparticles with a lognormal GSD. Results show that the TDS is affected highly by the GSD mainly in three aspects. Firstly, the unblocking process becomes smoother with the increase of distribution width, characterizing as a wider Hopkinson peak on the TDS curve. Secondly, the blocking temperature increases with the increase of the median diameter or/and the distribution width. Thirdly, the maximum susceptibility decreases with the increase of distribution width, and has a logarithmic function relation with the standard deviation of the distribution. As a case study, this model was further applied to the thermal products of the chinese loess/paleosol samples to determine the granulometry of newly-formed magnetite upon heating based on TDS curves. The results demonstrate the fidelity and feasibility of this method to determine the GSD of nano-sized magnetic particles.

关键词： Néel theory temperature dependence of susceptibility grain size distribution

Conceptual design and simulation analysis of thermal behaviors of TGR blast furnace and oxygen blast furnace

在线全文

学校读者我要写书评

暂无评论

Science china(Technological sciences) 2010年第1期53卷 85-92页

作者： ZHANG Hui1,2.LI HuiQuan1,TANG Qing1 & BAO WeiJun1 1 National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology,Institute of Process Engineering,chinese academy of {2.,beijing 100190,china 2.graduate University of chinese academy of {2.,beijing 100049,china National Engineering Laboratory for Hydrometallurgical Cleaner Production Technology Institute of Process Engineering Chinese Academy of Sciences Beijing China graduate University of chinese {2. of sciences Beijing China

Extensive use of carbon based fuel is the main inducement for global warming and more extreme *** carbon dioxide emission and enhancing energy use is a common subject in steel *** the integrated steel plant,decreasing carbon dioxide emission must consider energy balance in the whole iron and steel works,and secondary energy must be actively *** promising blast-furnaces,top gas recovery blast furnace(TGR-BF) and oxygen blast furnace have been *** this paper,conceptual TGR blast furnace and oxygen blast furnace are *** on the idea of blast furnace gas de-CO2.circulating as reducing agent and the idea of pure oxygen blast decreasing the thermal reserve zone temperature,process modeling is conducted with ASPEN *** is shown that the developed model reasonably describes the energy balance and mass balance feature of the furnace,and provides basic thermodynamic condition for *** effects of changes in different operation conditions are studied by sensitivity analysis and reference data from simulation.

关键词： TGR blast-furnace thermal behavior simulation analysis CO2 emission decreasing

Debris Flow Hazard Assessment Based on Support Vector Machine

在线全文

学校读者我要写书评

暂无评论

Wuhan University Journal of Natural sciences 2006年第4期11卷 897-900页

作者： YUAN Lifeng 1, 2., ZHANG Youshui 3 1. Institute of Mountain Hazards and Environment, chinese academy of {2., Chengdu 610041, Sichuan, china 2. graduate University of chinese academy of {2., beijing 100049, china 3. Institute of Geographical {2. and Natural Resources Research, chinese academy of {2., beijing 100101, china Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu Sichuan China graduate University of chinese {2. of sciences Beijing China Institute of Geographical sciences and Natural Resources Research Chinese Academy of Sciences Beijing China

Seven factors, including the maximum volume of once flow , occurrence frequency of debris flow , watershed area , main channel length , watershed relative height difference , valley incision density and the length ratio of sediment supplement are chosen as evaluation factors of debris flow hazard degree. Using support vector machine （SVM） theory, we selected 2.9 basic data of 37 debris flow channels in Yunnan Province as learning samples in this study. We create a debris flow hazard assessment model based on SVM. The model was validated though instance applications and showed encouraging results.

关键词： debris flow hazard assessment support vector machine (SVM)

CH_4 uptake flux of Leymus chinensis steppe during rapid growth season in Inner Mongolia,china

在线全文

学校读者我要写书评

暂无评论

Science china Earth sciences 2010年第7期53卷 977-983页

作者： GENG YuanBo1, LUO GuangQiang1,2.& YUAN GuoFu1 1 Institute of Geographic sciences and Natural Resources Research, chinese {2. of sciences, beijing 100101, china 2.graduate University of chinese {2. of sciences, beijing 100049, china Institute of Geographic sciences and Natural Resources Research Chinese Academy of Sciences Beijing China graduate University of chinese {2. of sciences Beijing China

The influence of near ground atmosphere CH4 concentration, soil water content, soil Eh, plants, soil temperature, and pH on CH4 uptake flux of Leymus chinensis steppe during rapid growth season was studied using field in-situ measurement in Xilin River basin of Inner Mongolia, china. The results showed that CH4 uptake flux was positively correlated with near ground atmosphere CH4 concentration and soil Eh but negatively correlated with soil water content. Precipitation may decrease the CH4 flux by increasing the soil water content. The average fluxes of three treatments during the observation period were 1.52.(natural conditions, 1.51 (aboveground plants were excluded), and 2.00 mg m?2.d?1 (all plants were removed), respectively. The difference between the CH4 flux of natural condition treatment and that of removing aboveground plants treatment is small, whereas the flux of removing all plants treatment is larger than the other two treatments. This means that the contribution of aboveground plants to CH4 uptake flux is smaller than that of roots or roots-removing process. CH4 uptake flux is not sensitive to soil temperature and the narrow-ranged soil pH (6.36–7.86). The Leymus chinensis steppe acts as a sink for CH4, and thus more studies should be focused on its affecting factors and related mechanisms.

关键词： CH4 uptake flux Leymus chinensis steppe affecting factors static opaque chamber/gas chromatography method

Bio-regeneration of p-complexation desulfurization adsorbents

在线全文

学校读者我要写书评

暂无评论

Science china Chemistry 2005年第6期48卷 538-544页

作者： LI Wangliang1,2. XING Jianmin1, XIONG Xiaochao1,2. SHAN Guobin1,2.& LIU Huizhou1 1. Laboratory of Separation Science and Engineering, Institute of Process Engineering, chinese academy of {2., beijing 100080, china 2. graduate School of the chinese academy of {2.,beijing 100039, china Laboratory of Separation Science and Engineering Institute of Process Engineering Chinese Academy of Sciences Beijing China graduate School of the chinese {2. of sciences Beijing China

The coupling of adsorption desulfurization and biodesulfurization is a new approach to produce clean fuels. Sulfur compounds are firstly adsorbed on adsorbents, and then the ad-sorbents are regenerated by microbial conversion. p-Complexation adsorbent, Cu(I)-Y, was ob-tained by ion exchanging Y-type zeolite with Cu2. and then by auto-reduction in helium at 450℃ for 3 h. Dibenzothiophene (DBT) was used as a model compound. The effects of cell concentra-tion, volume of oil phase, the ratio of aqueous phase to adsorbent on DBT desorption by a bac-terium were studied. The amounts of DBT desorbed and 2.HBP produced can be apparently increased with addition of n-octane. BDS activity can be improved by increasing cell concentra-tion and the ratio of water-to-adsorbent. 89% of DBT desorbed from the adsorbents can be converted to 2.HBP within 6 h and almost 100% within 2. h, when the volume ratio of oil-to-water was 1/5 mL/mL, the cell concentration was 60 g·L?1, and the ratio of adsorbent-to-oil was 0.03 g·mL?1. The amount of 2.HBP produced was strongly dependent on the volume ratio of oil-to- water, cell concentration and amount of adsorbent. Adsorption capacity of the regenerated ad-sorbent is 95% that of the fresh one after being desorbed with Pseudomonas delafieldii R-8, washed with n-octane, dried at 100℃ for 2. h and auto-reduced in He.

关键词： adsorption desulfurization p-complexation adsorbents bio-regeneration Pseudomonas delafieldii desorption.

Novel Tumor-associated Antigen of Hepatocellular Carcinoma Defined by Monoclonal Antibody E4-65

在线全文

学校读者我要写书评

暂无评论

Acta Biochimica et Biophysica Sinica 2007年第5期39卷 359-365页

作者： Ke ZOU~(1,2., Jihang JU~(1,2., and Hong XIE~~(1*)1 Institute of Biochemist13, and Cell Biology, Shanghai Institutes for Biological sciences, chinese {2. of sciences, Shanghai 2.0031, china. 2.graduate School of the chinese {2. of sciences beijing 100049, china Institute of Biochemistry and Cell Biology Shanghai Institutes for Biological Sciences Chinese Academy of SciencesShanghai 200031 China graduate School of the chinese {2. of sciencesbeijing 100049 China

A monoclonal antibody, E4-65, produced by immunizing mice with SMMC-772. cells, a human hepatocellular carcinoma (HCC) cell line, was used to identify and characterize an unreported HCC-associated antigen. Indirect immunofluorescence studies showed that E4-65 antibody reacted with five out of eight HCC cell lines, but not with 10 non-HCC tumor cell lines or a normal liver cell line. Using immunohistochemical examination, E4-65 antigen was detected on the cell membranes and in the cytoplasm of human liver tumor tissues, but was not found in most other tumors, or normal adult or fetal tissues, except for a weakly positive reaction in tissues of the digestive system. Western blot analysis showed that E4-65 antibody bound to a 45 kDa protein in the human HCC cell line and tissue lysates. Enzyme treatment and lectin blotting did not detect the carbohydrate chain in E4-65 antigen. This HCC-associated protein represents a potentially useful target for diagnoses and immunotherapy of human HCC.

关键词： hepatocellular carcinoma immunohistochemistry monoclonal antibody neoplasm antigen

Interannual variability of Antarctic Oscillation and its influence on East Asian climate during boreal winter and spring

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Science china Earth sciences 2006年第5期49卷 554-560页

作者： FAN Ke1,2.3 & WANG Huijun2.1. Nansen-Zhu International Research Center, Institute of Atmospheric Physics, chinese academy of {2., beijing 10002., china 2. Department of Atmospheric Science, Yunnan University, Kunming 650091, china 3. graduate University of the chinese academy of {2., beijing 100049, china Nansen-Zhu International Research Center Institute of Atmospheric Physics Chinese Academy of Sciences Beijing China Department of Atmospheric Science Yunnan University Kunming China graduate University of the chinese {2. of sciences Beijing China

The interannual variability of Antarctic Oscillation (AAO) and its influence on East Asian climate during both boreal winter and spring are addressed. The results show that the positive AAO anomaly decreases the cold activity over East Asia during both boreal winter and spring. AAO-related barotropic meridional teleconnection from Antarctic to Arctic is found through analysis of mean me- ridional circulations. This meridional teleconnection is remarkable over Eurasia during boreal winter and over the Pacific Ocean during boreal spring. The results also show that zonal mean zonal wind at high latitudes in Southern Hemisphere has well positive correlation with that of Eurasia during boreal winter and has negative correlation with Pacific North American teleconnection (PNA) during boreal spring, which again display the meridional teleconnection. Thus, local meridional teleconnection is a possible linkage for interaction of circulations at mid-high latitudes between both hemispheres.

关键词： Antarctic Oscillation, Eurasian west wind, meridional teleconnection, mean meridional circulation.

Taxonomic revision of Lepisorus(***.) Ching ***(Polypodiaceae) from china

在线全文

学校读者我要写书评

暂无评论

Journal of Systematics and Evolution 2009年第6期47卷 581-598页

作者： ~(1,2.Xin-Ping QI ~1Xian-Chun ZHANG~* 1(State Key Laboratory of Systematic and Evolutionary Botany,Institute of Botany,chinese academy of {2.,beijing 100093,china) 2.graduate University of chinese academy of {2.,beijing 100049,china) (State Key Laboratory of Systematic and Evolutionary Botany Institute of Botany Chinese Academy of Sciences Beijing 100093 China) (graduate University of chinese {2. of sciences Beijing 100049 China)

The taxonomy of Lepisorus(***.) Ching *** in china was revised based on herbarium specimen examinations,field observations,and microscopic study of rhizome scales,soral paraphyses,leaf epidermis, and *** a result,nine species were recognized:Lepisorus macrosphaerus(Baker) Ching,Lepisorus asterolepis (Baker) Ching,Lepisorus marginatus Ching,Lepisorus kuchenensis(***) Ching,Lepisorus megasorus(***.) Ching,Lepisorus kawakamii(Hayata) Tagawa,Lepisorus subsessilis Ching & ***,Lepisorus affinis Ching, and Lepisorus nudus(Hook.) *** kawakamii(Hayata) Tagawa was reinstated;Lepisorus gyirongensis Ching & *** and Lepisorus longus Ching were reduced to synonyms *** and ***,respectively. The subdivision ofLepisorus macrosphaerus was not *** scales and paraphyses are the most useful characters for species delimitation as well as for infrageneric *** of the leaf epidermis and spore ornamentation are usually stable and thus of great significance in understanding the relationships among groups within the genus.

关键词： china Lepisorus Lepisorus sect.Lepisorus Polypodiaceae taxonomic revision