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Present Situation and Prospects of High-purity Elements in China
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作者 Zhang Weihuo Emei Semiconductor Material Research Institute.Emei 614200,China 《Rare Metals》 SCIE EI CAS CSCD 1992年第3期228-231,共4页
1.IntroductionHigh-purity elements are the basic materials in electronics,communication,aerospace,atomicenergy and semiconductor material industries.Its development is a decisive factor for high-tech in-dustries.The h... 1.IntroductionHigh-purity elements are the basic materials in electronics,communication,aerospace,atomicenergy and semiconductor material industries.Its development is a decisive factor for high-tech in-dustries.The high-purification of non-ferrous metals is of great significance.It conduces to determining 展开更多
关键词 high CDTE In GAAS present situation and prospects of High-purity Elements in China
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The Present Situation and Prospects of China in Building Socialism
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《International Understanding》 1994年第1期5-8,共4页
ThePresentSituationandProspectsofChinainBuildingSocialismAttheinvitationofMr.Otani,MayorofHamadaofShinianeCo... ThePresentSituationandProspectsofChinainBuildingSocialismAttheinvitationofMr.Otani,MayorofHamadaofShinianeCounty,Japan,Mr.Zha... 展开更多
关键词 The present situation and prospects of China in Building Socialism
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The Present Situation and Development Countermeasures for Meat Products Industry in Henan 被引量:2
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作者 欧阳华澍 王国贞 +3 位作者 娄鹏雁 王东栋 苗双双 陈献文 《Agricultural Science & Technology》 CAS 2011年第8期1245-1248,共4页
This paper introduces the development and present situation of meat industry in Henan Province so as to get comprehensive understanding of this industry,including the advantages and insufficiencies of this industry,an... This paper introduces the development and present situation of meat industry in Henan Province so as to get comprehensive understanding of this industry,including the advantages and insufficiencies of this industry,and then puts forward some countermeasures for the future development of the meat products of Henan Province,to realize the rapid,healthy and sustainable development of meat industry in Henan and create huge economic and social benefits in Henan. 展开更多
关键词 Henan Province Meat products industry present situation Development countermeasures
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Present Situation and Benefit Analysis of the Straw Recycling in Southwest China 被引量:4
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作者 GAO Xue-song ZENG Min +1 位作者 DENG Liang-ji ZHONG Chang-biao 《Asian Agricultural Research》 2010年第2期40-44,共5页
Currently,sustainable agricultural development in China is facing some big challenges of how to promote the present developing pattern,to lengthen material transformation chain,to increase the utilization rate of mate... Currently,sustainable agricultural development in China is facing some big challenges of how to promote the present developing pattern,to lengthen material transformation chain,to increase the utilization rate of material and energy in agricultural system and to form a healthy agricultural ecological circulation system.China is a major country producing crops and straws.Both high-efficient utilizing pattern of straw and technological system are needed urgently.According to the field survey,we point out the status of straw utilization and the main recycling pattern in typical farming areas in Sichuan,China through the literature review and data collection.Based on the statistical analysis,the economic,environmental and social benefits of each utilization way are analyzed,and the methods and measures are proposed in order to promote recycling utilization of the straw in Sichuan farming area,and to offer theoretical guidance for energy saving,food safety,and pollution control. 展开更多
关键词 Straw utilization present situation BENEFIT SICHUAN China
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The Major Ore Clusters of Super-Large Iron Deposits in the World, Present Situation of Iron Resources in China, and Prospect 被引量:2
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作者 ZHAO Yiming FENG Chengyou LI Daxin 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2014年第6期1895-1915,共21页
The metamorphosed sedimentary type of iron deposits(BIF) is the most important type of iron deposits in the world, and super-large iron ore clusters of this type include the Quadrilatero Ferrifero district and Caraj... The metamorphosed sedimentary type of iron deposits(BIF) is the most important type of iron deposits in the world, and super-large iron ore clusters of this type include the Quadrilatero Ferrifero district and Carajas in Brazil, Hamersley in Australia, Kursk in Russia, Central Province of India and Anshan-Benxi in China. Subordinated types of iron deposits are magmatic, volcanic-hosted and sedimentary ones. This paper briefly introduces the geological characteristics of major super-large iron ore clusters in the world. The proven reserves of iron ores in China are relatively abundant, but they are mainly low-grade ores. Moreover, a considerate part of iron ores are difficult to utilize for their difficult ore dressing, deep burial or other reasons. Iron ore deposits are relatively concentrated in 11 metallogenic provinces(belts), such as the Anshan-Benxi, eastern Hebei, Xichang-Central Yunnan Province and middle-lower reaches of Yangtze River. The main minerogenetic epoches vary widely from the Archean to Quaternary, and are mainly the Late Archean to Middle Proterozoic, Variscan, and Yanshanian periods. The main 7 genetic types of iron deposits in China are metamorphosed sedimentary type(BIF), magmatic type, volcanic-hosted type, skarn type, hydrothermal type, sedimentary type and weathered leaching type. The iron-rich ores occur predominantly in the skarn and marine volcanic-hosted iron deposits, locally in the metamorphosed sedimentary type(BIF) as hydrothermal reformation products. The theory of minerogenetic series of mineral deposits and minerogenic models has applied in investigation and prospecting of iron ore deposits. A combination of deep analyses of aeromagnetic anomalies and geomagnetic anomalies, with gravity anomalies are an effective method to seeking large and deep-buried iron deposits. China has a relatively great oresearching potential of iron ores, especially for metamorphosed sedimentary, skarn, and marine volcanic-hosted iron deposits. For the lower guarantee degree of iron and steel industry, China should give a trading and open the foreign mining markets. 展开更多
关键词 major ore clusters of super-large iron deposits present situation of iron ore resources in China genetic type temporal-spatial distribution ore-searching potential
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Present situation and future of welding machinery industry  被引量:5
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作者 LI Jianguo and ZHU Qi (Chengdu Electric Welding Machine Research Institute (610051 )) 《China Welding》 EI CAS 1994年第2期142-145,共4页
The present situation of welding machinery industry in China is presented in detail.On the basis of the analysis, the future development and practicable way are proposed.
关键词 present situation and future of welding machinery industry
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Management present situation and countermeasures of coal mines safety in production 被引量:1
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作者 张树东 于常武 《Journal of Coal Science & Engineering(China)》 2008年第2期326-328,共3页
Analyzed of the present situation of Chinese coal mines safety in production and the reasons for coal mining accident,and realized the coal mines safety in production, which should increase the legal safeguards of coa... Analyzed of the present situation of Chinese coal mines safety in production and the reasons for coal mining accident,and realized the coal mines safety in production, which should increase the legal safeguards of coal mine safety in production,and safety input,established the comprehensive coal mine safety evaluation system,comprehen- sively enhance quality of coal mine workers,established and improved early warning me- chanism of safety production of coal mine. 展开更多
关键词 coal mine safety COUNTERMEASURES present situation MANAGEMENT
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Present Situations and Suggestions for Large-scale Development of Chenopodium quinoa Willd. 被引量:1
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作者 Wei LU Xinyu WANG +4 位作者 Yu ZHAO Ming GUO Meiyan PEI Zhimin WEI Chuan LU 《Asian Agricultural Research》 2021年第3期14-16,共3页
In this paper,based on the study of Chenopodium quinoa Willd.planting,it is concluded that the current situations of large-scale development of C.quinoa Willd.include the following four aspects:first,the research on C... In this paper,based on the study of Chenopodium quinoa Willd.planting,it is concluded that the current situations of large-scale development of C.quinoa Willd.include the following four aspects:first,the research on C.quinoa Willd.varieties needs to be strengthened;second,it is insufficient to master the training environment and cultivation techniques;third,the large-scale planting of C.quinoa Willd.is not enough;fourth,the degree of mechanization of C.quinoa Willd.planting is not enough.In view of the above situation,this paper puts forward the following effective suggestions to strengthen the large-scale development of C.quinoa Willd.:the first is to increase the investment in C.quinoa Willd.variety research;the second is to strengthen the analysis of introduction and screening of C.quinoa Willd.varieties;the third is to study the best planting environment and cultivation techniques of C.quinoa Willd.;the fourth is to increase the scale of mechanized production of C.quinoa Willd.;the fifth is to increase the research and development of C.quinoa Willd.related products and their deep processing technology. 展开更多
关键词 Chenopodium quinoa Willd. Large-scale development present situations Suggestions
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Present Situation of China's Shale Gas Exploration and Development 被引量:1
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作者 LIU Zhiqiang LIU Lian +4 位作者 HUANG Min FEI Hongcai ZHOU Jian ZHANG Yuxu HAO Ziguo 《Acta Geologica Sinica(English Edition)》 CAS CSCD 2018年第5期2026-2027,共2页
In recent years,with China's continuous investment in shale gas exploration and the continuous efforts of scientific workers,China’s shale gas exploration and development has achieved leap-forward development.In2011... In recent years,with China's continuous investment in shale gas exploration and the continuous efforts of scientific workers,China’s shale gas exploration and development has achieved leap-forward development.In2011,China's State Council approved shale gas as a new mineral resource.In 2014,shale gas was first proved at geological reserves of 106.8 billion m^3. 展开更多
关键词 present situation of China’s Shale Gas Exploration and Development
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Thoughts on Present Situation of Development of Rural Animal Husbandry and Its Relationship with Construction of Ecological Agriculture and Revitalization of Rural Industry 被引量:1
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作者 Dejun TAN Guogui WANG +4 位作者 Yunfen ZHU Xiaofei CHEN Jin MA Rong LI Junhui XIE 《Asian Agricultural Research》 2021年第7期20-23,31,共5页
After several rounds of phased ups and downs of development,rural animal husbandry finally presents a shrinking and depressed development situation under the comprehensive action of the failure of transformation and u... After several rounds of phased ups and downs of development,rural animal husbandry finally presents a shrinking and depressed development situation under the comprehensive action of the failure of transformation and upgrading and the increasing production costs and breeding risks.Actively exploring and guiding the healthy and sound development of rural animal husbandry is not only an important measure to promote the construction of ecological agriculture,but also the main starting point to realize the revitalization of rural industry.This paper analyzes the present situation of the development of rural animal husbandry in recent years,the influence of animal husbandry on the construction of ecological agriculture and the revitalization of rural industry,and puts forward the corresponding measures,in order to promote the steady and efficient development of animal husbandry in the grand strategy of revitalizing rural industry. 展开更多
关键词 present situation of the development of rural animal husbandry Construction of ecological agriculture Revitalization of rural industry
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Present Situation and Prospect of Grub Control in Sweet Potato Field
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作者 Yan Hui Xue Cheng +1 位作者 Li Qiang Zhang Yungang 《Plant Diseases and Pests》 CAS 2015年第2期1-4,15,共5页
Grub is one of the major pests affecting yield and quality of sweet potato. Although traditional chemical pesticides have quick effect, the disadvantages of high toxicity, strong pest resistance, and heavy pollution h... Grub is one of the major pests affecting yield and quality of sweet potato. Although traditional chemical pesticides have quick effect, the disadvantages of high toxicity, strong pest resistance, and heavy pollution hinder the development of modern ecological agriculture, while physical means such as light trapping, sex pheromone method and biological control methods are more safe and lasting compared with chemical means. To provide reference and guidance for grub control and sweet potato production, the control methods against sweet potato grubs are comprehensively explored, and strategy and prospects of using biological technology to control pests are analyzed. 展开更多
关键词 Sweet potato GRUB Biological control present situation PROSPECT
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Present Status and Future Prospects of Laser Fusion Research at ILE Osaka University
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作者 K.Mima K.A.Tanaka +13 位作者 R.Kodama T.Johzaki H.Nagatomo H.Shiraga Y.Sentoku N.Miyanaga H.Azechi M.Nakai T.Norimatu K.Nagai J.Sunahara K.Nishihara T.Taguchi H.Sakagami 《Plasma Science and Technology》 SCIE EI CAS CSCD 2004年第1期2179-2184,共6页
Reviewed are the present status and future prospects of the laser fusionresearch at the ILE Osaka. The Gekko XII and Peta Watt laser system have been operated forinvestigating the implosion hydrodynamics, fast ignitio... Reviewed are the present status and future prospects of the laser fusionresearch at the ILE Osaka. The Gekko XII and Peta Watt laser system have been operated forinvestigating the implosion hydrodynamics, fast ignition, and the relativistic laser plasmainteractions and so on. In particular, the fast ignition experiments with cone shell target havebeen in progress as the UK and US-Japan collaboration programs. In the experiments, the implodedhigh density plasmas are heated by irradiating 500 J level peta-watt laser pulse. The thermalneutron yield is found to increase by three orders of magnitude by injecting the peta-watt laserinto the cone shell target. The Rayleigh-Taylor instability experiment results are also reviewed isthis paper. 展开更多
关键词 laser fusion present ststus future prospects
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Present situation and countermeasure of low-alloy spring steel wire rod for domestic automobile
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作者 XING Xianqiang Sinosteel Zhengzhou Research Institute of Steel Wire Products Co.,Ltd., Zhengzhou 450001,Henan,China 《Baosteel Technical Research》 CAS 2010年第S1期60-,共1页
The variety,inner quality and surface quality of low-alloy spring steel wire rod for domestic automobile is summarized in detail.And according to commercial low-alloy spring steel wire rod variety, product quality lev... The variety,inner quality and surface quality of low-alloy spring steel wire rod for domestic automobile is summarized in detail.And according to commercial low-alloy spring steel wire rod variety, product quality level and its actual application situation on automobile supplied by present industrially developed country metallurgy enterprises,it is pointed that the variety of low-alloy spring steel wire rod for domestic automobile can't satisfy the requirements of automobile industry development,compare with overseas advanced technology,product quality has the following gaps:the first is that steel purity is low,the control level of non-metallic inclusions is not steady,there is often large grain difficult deforming non-deformation inclusions existing,the control level of steel purity has big difference,the level of large steel factory is high,but its steady has a large gap compare with foreign advanced level,not to mention small steel factory which research and development powder is low.The second is surface complete decarburization can' t be avoided completely.The third is that surface defects are more.The fourth is that composition segregation and structure segregation are not steady,steel wire can't be drawn normally when the segregation is serious. In all,the segregation of 55SiCrA is superior to 60Si2MnA obviously.The industrialization of domestic high level low-alloy spring steel wire rod can't seek quick success and instant benefits,independent innovation perseveringly must be adopted,the success may be reached after master core technologies and adopt the science way of step by step. 展开更多
关键词 AUTOMOBILE low-alloy spring steel wire rod present situation COUNTERMEASURE
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Investigation of Present Situation of Urban Road Traffic in Nanchang City and Countermeasures
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作者 ZENG Yan MIN Zhongrong +1 位作者 XU Wei YU Zhenya 《Journal of Landscape Research》 2017年第1期1-4,7,共5页
The present situation of urban road traffic in Nanchang City was surveyed systematically from the present situation of the road structure,characteristics of trafficvolume,residents' trips,etc.,then the existing pr... The present situation of urban road traffic in Nanchang City was surveyed systematically from the present situation of the road structure,characteristics of trafficvolume,residents' trips,etc.,then the existing problems were analyzed,and some countermeasures were put forward finally. 展开更多
关键词 Nanchang City Road traffic present situation INVESTIGATION
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The Present Situation of Chattel Guarantee System and Its Improvements—Taking the Angle of American Uniform Commercial Code(UCC)
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作者 仇晓光 刘聪 《海外英语》 2011年第12X期376-379,共4页
Although there are appropriate stipulations for the chattel guarantees in the law of China, this guarantee system could not adapt to the request of economy's development because of the following reasons: the scope... Although there are appropriate stipulations for the chattel guarantees in the law of China, this guarantee system could not adapt to the request of economy's development because of the following reasons: the scope of chattel guarantees is narrow according to relevant stipulations; the transaction cost of the chattel is high; mortgage registration of chattel is in a mess; lack of efficiently executive guarantee system, etc. To counter the problems existing in the present Chinese chattel guarantee system, in this article, the author proposed some corresponding suggestions and countermeasures, hoping to perfect the chattel guarantee system in China. 展开更多
关键词 Chattel GUARANTEE System AMERICAN UNIFORM COMMERCIAL CODE present situation
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Research present situation and analysis on classification of rock drillability
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作者 张志红 马芹永 《Journal of Coal Science & Engineering(China)》 2001年第1期39-45,共7页
Rock drillability reflects the drill bit fragments rock hardly or easily. At present, rock drillability classification indexes have rock single axle compressive strength, point load intensity, fracture stress during c... Rock drillability reflects the drill bit fragments rock hardly or easily. At present, rock drillability classification indexes have rock single axle compressive strength, point load intensity, fracture stress during chiseling, drill speed, chiseling specific work, acoustic parameter, cutting magnitude and so on. Every index reflects rock drillability but isnt overall. It is feasible that using many indexes of fuzzy mathematics method etc. to evaluate rock drillability. 展开更多
关键词 DRILLABILITY ROCK CLASSIFICATION research present situation INDEX
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An Analysis on Present Situation of Land Use Based on GIS in Caocun Town
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作者 Zhan HUANG Zhongxiang YU 《Asian Agricultural Research》 2017年第3期52-56,共5页
Taking Caocun Town for example,we use GIS technology to systematically analyze the present situation of land use in Caocun Town on the basis of land reclamation rate model and land use degree model from quantitative s... Taking Caocun Town for example,we use GIS technology to systematically analyze the present situation of land use in Caocun Town on the basis of land reclamation rate model and land use degree model from quantitative structure,spatial distribution and degree of land use,in order to provide a basis for adjustment and optimization of land use structure,comprehensive land consolidation and full tapping of land use potential in Caocun Town,and provide a reference for rational land use and land protection policy formulation. 展开更多
关键词 present situation of land use GIS Caocun Town
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THE PRESENT SITUATION OF THE DEVELOPMENT OF RARE EARTHS IN CHINA
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作者 Liu Yujiu(Bureau of Rare and Rare Earth Metals,China National Nonferrous Metals Industry Corporation,Beijing P.R.China) 《Journal of Rare Earths》 SCIE EI CAS CSCD 1990年第1期67-73,共7页
1.Rare Earth Resources in China1.1.Reserves and distributionChina is the country which is the richest in the world in rare earth(RE)resources of allavailable varieties of minerals and their deposits are located in vas... 1.Rare Earth Resources in China1.1.Reserves and distributionChina is the country which is the richest in the world in rare earth(RE)resources of allavailable varieties of minerals and their deposits are located in vast areas in China.Reserveshave been estimated at a grand total of 36 million ton,which is 80% of the world(RE)de-posits.The majority of these deposits are concentratedly located in Baiyunebo mine of the 展开更多
关键词 RE THE present situation OF THE DEVELOPMENT OF RARE EARTHS IN CHINA
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Survey and Analysis on Present Situation of Biological Experiment Teaching in Some Middle Schools in Yangjiang Area
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作者 Sainan LI Haoyao WU +1 位作者 Yina LU Liping ZHOU 《Asian Agricultural Research》 2021年第5期53-56,共4页
Experimental teaching is an important part of biology teaching in middle school.In the form of questionnaire,this paper conducts a survey on some leading teachers of biology in the middle schools in the Yangjiang area... Experimental teaching is an important part of biology teaching in middle school.In the form of questionnaire,this paper conducts a survey on some leading teachers of biology in the middle schools in the Yangjiang area about the biological experiment teaching in the implementation of the new curriculum,and analyzes the results of the survey.The problems and deficiencies in the implementation of biological experiment teaching in some middle schools in this area are found,and the relevant reform measures and suggestions are put forward in order to promote the better development of biological experiment teaching in middle schools. 展开更多
关键词 Biological experiment teaching in middle school present situation Questionnaire survey ANALYSIS
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Analysis of TEDA's Present Situation in Drawing Capital from Transnational Corporations and Its Measures
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作者 Chi Chang-gui Wan Qian Chen Lan-yi M. A. of economics. Vice Director of the Commission Office of TEDA Deputy Chief of Secretary Seation of the Commission Office of TEDA M. A. of economics, Secretary Section of the Commission of TEDA 《南开经济研究》 CSSCI 北大核心 1994年第S3期46-54,共9页
Ⅰ. The present Situation of Transnational Corporations’ Investment in TEDA (1 ) General situation Since its founding ten years ago, especially since 1992. TEDA has achieved encouraging successesin undertaking major ... Ⅰ. The present Situation of Transnational Corporations’ Investment in TEDA (1 ) General situation Since its founding ten years ago, especially since 1992. TEDA has achieved encouraging successesin undertaking major projects. drawing the attention of leading consortia, omnibearingly solicitingbusiness and drawing foreign capital. By September 30, 1994, TEDA had approved 2054 solely for- 展开更多
关键词 TEDA Analysis of TEDA’s present situation in Drawing Capital from Transnational Corporations and Its Measures
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