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Semi-solid A356 alloy slurry for rheocasting prepared by a new process 被引量:3
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作者 Liu Zheng Liu Xiaomei Mao Weimin 《China Foundry》 SCIE CAS 2013年第3期176-180,共5页
To obtain the semi-solid slurry with uniform and fine structure morphology that satisfies the requirement of rheocasting process, a new process for preparing semi-solid AI alloy slurry was developed, in which local ch... To obtain the semi-solid slurry with uniform and fine structure morphology that satisfies the requirement of rheocasting process, a new process for preparing semi-solid AI alloy slurry was developed, in which local chilling was combined with low superheat pouring and slight electromagnetic stirring (LSPSEMS). The morphology and the size of primary a-AI in the A356 alloy slurry prepared with the new process, i.e., LSPSEMS with local chilling, were investigated using MIAPS image analyzing software, and the grain refinement mechanism was discussed. The results indicate that the semi-solid primary phase consists of particle-like or globular-like a-AI, and the morphology and grain size of primary a-AI in the slurry can be markedly improved by the new process. The fine primary a-AI distributes uniformly in the slurry, which satisfies the requirement of rheocasting. Compared with the alloy prepared by LSPSEMS, the average equal-area-circle grain diameter of primary a-AI in semi-solid A356 alloy ingot prepared by the new process is decreased from 85.6μm to 68.8 μm at the central area, 112.6 μm to 77.6 μm at the transition area and is 84.7 μm in the edge area, respectively. The corresponding shape factor of primary a-AI is increased from 0.78 to 0.83, 0.54 to 0.77 and 0.28 to 0.59, respectively. In addition, the pouring temperature could be suitably raised from 620-630℃ of the traditional process to 650℃ using this technique, which is convenient for practical operation. The mechanism of grain refinement, in the new process, is that the local chilling quickens up the temperature decrease in the center of the melt. The nuclei could not grow up in a short time so the finer grains are formed in the melt. 展开更多
关键词 SEMI-SOLID A356 alloy new process RHEOCASTING
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Study on the mechanism of coal liquefaction reaction and a new process concept 被引量:1
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作者 史士东 李文博 +2 位作者 王勇 郭治 李克健 《Journal of Coal Science & Engineering(China)》 2008年第1期119-124,共6页
The coal hydrogenation reaction process is simply considered as three steps.In the first step,the smaller molecules associated with coal structure units are released as some gases and water in the condition of solvent... The coal hydrogenation reaction process is simply considered as three steps.In the first step,the smaller molecules associated with coal structure units are released as some gases and water in the condition of solvent and heating.In this step,some weaker bonds of the coal structure units are ruptured to form free radicals.The radicals are stabi- lized by hydrogen atoms from donor solvent and/or H2.In the second step,chain reaction occurs quickly.In the process of chain reaction,the covalent bonds of coal structure units are attacked by the radicals to form some asphaltenes.In the third step,asphaltenes are hydrogenated form more liquids and some gases.In coal liquefaction,the second step of coal hydrogenation reaction should be controlled to avoid integration of radicals,and the third step of coal hydrogenation should be accelerated to increase the coal conversion and the oil yield.A new concept of coal liquefaction process named as China direct coal lique- faction (CDCL) process is presented based on the mechanism study of coal liquefaction. 展开更多
关键词 coal liquefaction reaction mechanism new process
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A New Synthesis Process of Highly Efficient and Low Toxic Fungicide Difenoconazole
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作者 He Yongli Zhou Wei Tao Yachun 《Plant Diseases and Pests》 CAS 2020年第2期14-15,共2页
A new synthesis method of difenoconazole is studied.Difenoconazole is prepared from m-dichlorobenzene by Friedel Crafts reaction,cyclization,bromination,nucleophilic substitution and etherification.The new process imp... A new synthesis method of difenoconazole is studied.Difenoconazole is prepared from m-dichlorobenzene by Friedel Crafts reaction,cyclization,bromination,nucleophilic substitution and etherification.The new process improves the selectivity of the reaction and simplified the pu-rification process.The total yield of this process is 84%,which provides a green and economical synthetic route for industrialization. 展开更多
关键词 DIFENOCONAZOLE SYNTHESIS new process
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High Spatial Resolution Mapping of Dykes Using Unmanned Aerial Vehicle(UAV) Photogrammetry: New Insights On Emplacement Processes 被引量:1
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作者 Alexander CRUDEN Stefan VOLLGGER +1 位作者 Greg DERING Steven MICKLETHWAITE 《Acta Geologica Sinica(English Edition)》 SCIE CAS CSCD 2016年第S1期52-53,共2页
Remote sensing has played a pivotal role in our understanding of the geometry of dykes and dyke swarms on Earth,Venus and Mars(West and Ernst,1991;Mege and Masson,1995;Ernst et al.,2005).Since the 1970’s
关键词 PHOTOGRAMMETRY High Spatial Resolution Mapping of Dykes Using Unmanned Aerial Vehicle new Insights On Emplacement processes UAV
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Three-Dimensional Rigid-Plastic FEM Simulation of Bulk Forming Processes with New Contact and Remeshing Techniques 被引量:1
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作者 Debin Shan and Youngsuk Kim School of Mechanical Engineering, Kyungpook National University, Taegu 702-70 1, South Korea Hyunsoo Kim Graduate School of Mechanical Engineering, Kyungpook National University, Taegu 702-701, South Korea E-mail: shandb@public 《Journal of Materials Science & Technology》 SCIE EI CAS CSCD 2001年第3期329-332,共4页
Some techniques such as die surface description, contact judgement algorithm and remeshing are proposed to improve the robustness of the numerical solution. Based on these techniques, a three-dimensional rigid-plastic... Some techniques such as die surface description, contact judgement algorithm and remeshing are proposed to improve the robustness of the numerical solution. Based on these techniques, a three-dimensional rigid-plastic FEM code has been developed. Isothermal forging process of a cylindrical housing has been simulated. The simulation results show that the given techniques and the FEM code are reasonable and feasible for three-dimensional bulk forming processes. 展开更多
关键词 Three-Dimensional Rigid-Plastic FEM Simulation of Bulk Forming processes with new Contact and Remeshing Techniques FEM Simulation
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NEW PROGRESS IN MINERAL PROCESSING——REPORT ON FIRST INTERNATIONAL CONFERENCE ON MODERN PROCESS MINERALOGY AND MINERAL PROCESSING 被引量:1
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作者 Shi Daxin (Beijing General Research Institute of Mining and Metallurgy, Beijing 100044) 《有色金属》 CSCD 1993年第3期81-84,共4页
The first International Conference on Modern Process Mineralogy and Mineral Processing, organized by the Nonferrous Metals Society of China and hosted by Beijing General Research Institute of Mining and Metallurgy,was... The first International Conference on Modern Process Mineralogy and Mineral Processing, organized by the Nonferrous Metals Society of China and hosted by Beijing General Research Institute of Mining and Metallurgy,was held on September 22-25,1992,in Beijing,China.About 350 scholars and experts from 25 countries and regions showed up at the conference and 130 papers were presented,among them 98 papers are of mineral processing.Some of the papers given in mineral processing are summed up as follows. 展开更多
关键词 new PROGRESS IN MINERAL processING REPORT ON FIRST INTERNATIONAL CONFERENCE ON MODERN process MINERALOGY AND MINERAL processING
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New process of low-temperature methanol synthesis from CO/CO_2/H_2 based on dual-catalysis
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作者 曾健青 TSUBAKINoritatsu FUJIMOTOKaoru 《Science China Chemistry》 SCIE EI CAS 2002年第1期106-112,共7页
A new process of low-temperature methanol synthesis from CO/CO2/H2 based on dual-catalysis has been developed. Some alcohols, especially 2-alcohol, were found to have high catalytic promoting effect on the synthesis o... A new process of low-temperature methanol synthesis from CO/CO2/H2 based on dual-catalysis has been developed. Some alcohols, especially 2-alcohol, were found to have high catalytic promoting effect on the synthesis of methanol from CO hydrogenation. At 443 K and 5 MPa, the synthesis of methanol could process high effectively, resulting from the synergic catalysis of Cu/ZnO solid catalyst and 2-alcohol solvent catalyst. The primary results showed that when 2-butanol was used as reaction solvent, the one-pass average yield and the selectivity of methanol, in 40 h continuous reaction at temperature as low as 443 K and 5 MPa, were high up to 46.51% and 98.94% respectively. The catalytic activity was stable and the reaction temperature was 80 K or so lower than that in current industry synthesis process. This new process hopefully will become a practical method for methanol synthesis at low temperature. 展开更多
关键词 dual-catalysis METHANOL LOW-TEMPERATURE SYNTHESIS new process.
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The New Standards System for Processing Food to Be Proved
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《China Standardization》 2005年第2期34-35,共2页
It is reported that the work of re-structuring the frame of China nationalstandards system for processing food has been finished with the print and distribution of 2004-2005Development Plan of National Standards for F... It is reported that the work of re-structuring the frame of China nationalstandards system for processing food has been finished with the print and distribution of 2004-2005Development Plan of National Standards for Food (hereinafter Plan). According to the demand of thePlan, there will be great changes among the current national standards and the professionalstandards for processing food, in which some standards will be integrated with others, somestandards will be cancelled, and some will be brought into the new standards system after the reviewof standards. The standards after being changed and the new national standards and the professionalstandards that need to be developed compose the new standards system for processing food. 展开更多
关键词 BE The new Standards System for processing Food to Be Proved
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A NEW HEAT-TREATMENT PROCESS FOR 2014 ALUMINUM ALLOY AND ITS MECHANISM
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作者 Wang, Lingyun Huang, Guangjie Chao, Denju Chongqing Univsrsity, Chongqing 630044, China 《中国有色金属学会会刊:英文版》 CSCD 1993年第3期42-47,共6页
The plan of heat-treatment process for 2014Al alloy is designed using orthogonal method, the heat-treatment experiments are made and the mechanical properties are tested according to the designed plan. The effect of s... The plan of heat-treatment process for 2014Al alloy is designed using orthogonal method, the heat-treatment experiments are made and the mechanical properties are tested according to the designed plan. The effect of solid solution temperature, ageing temperature, ageing time on microscopic mechanism of the mechanical properties of the 2014Al alloy is studied using microscope, transmission electron microscope. The best heat treatment process of the 2014Al alloy is developed. The experimental results indicate that the strength σ<sub>b</sub>, yield stress σ<sub>0.2</sub>, percentage elongation δ of the alloy reach separately 490~500 MPa, 450~490 MPa, 10~12% adopting the new heat treatment process. Compared with GB, the strength increases 20~30%, the percentage elongation increases 30~40%. The mechanism of the new heat-treatment process is also discussed. 展开更多
关键词 2014Al new heat treatment process MECHANISM ULTIMATE tensile strength yield stress PERCENT age ELONGATION
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Feasibility study of a process for the reduction of sulfur oxides in flue gas of fluid catalytic cracking unit using the riser reactor
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作者 Fa-Lu Dang Gang Wang +2 位作者 Jing-Cun Lian Yu Yang Mei-Jia Liu 《Petroleum Science》 2025年第2期909-924,共16页
In this work,a new process for achieving the recovery of elemental sulfur by utilizing a fluidized catalytic cracking(FCC) riser reactor for SOxtreatment(FCC-DeSOx) is proposed.The process leverages the high temperatu... In this work,a new process for achieving the recovery of elemental sulfur by utilizing a fluidized catalytic cracking(FCC) riser reactor for SOxtreatment(FCC-DeSOx) is proposed.The process leverages the high temperatures and hydrocarbon concentrations in the FCC riser reactor to convert SOxinto H_(2)S.Subsequently,H_(2)S,along with the cracked gas,is processed downstream to produce sulfur.Thermodynamic analysis of the key reduction reactions in the FCC-DeSOxprocess revealed that complete conversion of SOxto H_(2)S is feasible in the dry gas(hydrogen-rich) prelift zone,as well as the upper and lower zones of the riser,upon achieving thermodynamic equilibrium.Experimental studies were conducted to replicate the conditions of these reaction zones using a low concentration of hydrogen gas as the reducing agent.Through process optimization,investigation of the minimum reaction time,and kinetic studies,the potential of this method for the complete reduction of SOxwas further confirmed. 展开更多
关键词 Sulfur oxides new catalytic cracking process Thermodynamic analysis Kinetic analysis Sulfur recovery
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NEW INQUIRY INTO THE APPLICATION OF CASE TOOLS TO CIM PROCESS
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作者 Ying Jing He Zhijun Huang Bo 《Computer Aided Drafting,Design and Manufacturing》 1996年第1期32-38,共2页
There is an urgent necessity to introduce the life cycle development method and a Computer-Aided Software Engineering (CASE) environment to support the development of a Computer Integrated Manufacturing (CIM) system. ... There is an urgent necessity to introduce the life cycle development method and a Computer-Aided Software Engineering (CASE) environment to support the development of a Computer Integrated Manufacturing (CIM) system. In this paper, we present several ideas while inquiring how to apply CASE tools to CIM process effectively, and propose five proper applicable paradigms to enhance the possibility of applications that the CIM process may make better use of CASE tools. 展开更多
关键词 CIM new INQUIRY INTO THE APPLICATION OF CASE TOOLS TO CIM process
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全过程的农业社会化服务对农业新质生产力的影响机制与空间效应研究
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作者 周为 程晨 《云南农业大学学报(社会科学版)》 2026年第1期17-25,共9页
农业新质生产力是农业现代化的现实要求,全过程的农业社会化服务区别于传统单一服务,覆盖生产全环节更能为农业新质生产力的发展提供坚实支撑。本研究基于2012—2023年中国30个省级面板数据,通过实证分析探讨全过程的农业社会化服务对... 农业新质生产力是农业现代化的现实要求,全过程的农业社会化服务区别于传统单一服务,覆盖生产全环节更能为农业新质生产力的发展提供坚实支撑。本研究基于2012—2023年中国30个省级面板数据,通过实证分析探讨全过程的农业社会化服务对农业新质生产力的影响及其作用机制。研究结果表明:第一,全过程的农业社会化服务通过提高劳动者素质、优化劳动资料配置与改善劳动对象利用水平直接推动农业新质生产力发展;第二,全过程的农业社会化服务通过促进农业效率提升、技术进步、创新驱动与规模经营,间接助力农业新质生产力发展;第三,全过程的农业社会化服务在邻近地区展现出显著的正向空间溢出效应。据此,本研究提出对策建议:构建全方位社会化服务体系,强化技术渗透与各要素协同;深化土地经营权市场化改革,释放规模经济效能;强化跨区域服务网络协同,放大空间溢出效应。 展开更多
关键词 农业社会化服务 农业新质生产力 全过程 机制分析 空间效应
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Review on biomass metallurgy:Pretreatment technology,metallurgical mechanism and process design 被引量:10
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作者 Jianliang Zhang Hongyuan Fu +4 位作者 Yanxiang Liu Han Dang Lian Ye Alberto N.Conejio Runsheng Xu 《International Journal of Minerals,Metallurgy and Materials》 SCIE EI CAS CSCD 2022年第6期1133-1149,共17页
The metallurgy industry consumes a considerable amount of coal and fossil fuels,and its carbon dioxide emissions are increasing every year.Replacing coal with renewable,carbon-neutral biomass for metallurgical product... The metallurgy industry consumes a considerable amount of coal and fossil fuels,and its carbon dioxide emissions are increasing every year.Replacing coal with renewable,carbon-neutral biomass for metallurgical production is of great significance in reducing global carbon consumption.This study describes the current state of research in biomass metallurgy in recent years and analyzes the concept and scientific principles of biomass metallurgy.The fundamentals of biomass pretreatment technology and biomass metallurgy technology were discussed,and the industrial application framework of biomass metallurgy was proposed.Furthermore,the economic and social advantages of biomass metallurgy were analyzed to serve as a reference for the advancement of fundamental theory and industrial application of biomass metallurgy. 展开更多
关键词 BIOMASS pretreatment technology blast furnace ironmaking direct reduction new process design benefit assessment
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“科教赛社”融合育人的新文科拔尖创新人才培养模式研究——以东北大学W学院为例
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作者 张晓杰 刘晓瑜 陈玉芬 《科教文汇》 2026年第2期73-78,共6页
培养新文科拔尖创新人才是新时代高等教育人才培养的重要目标之一。为解决传统教学中存在的理论与实践相脱节、科研与教学相隔离、学生学业与竞赛相分离的问题,东北大学W学院将教学创新、科研创新、竞赛创新、实践创新等四个人才培养创... 培养新文科拔尖创新人才是新时代高等教育人才培养的重要目标之一。为解决传统教学中存在的理论与实践相脱节、科研与教学相隔离、学生学业与竞赛相分离的问题,东北大学W学院将教学创新、科研创新、竞赛创新、实践创新等四个人才培养创新系统有机集成,提出“科教赛社”融合育人的新文科拔尖创新人才全过程培养模式。该模式着力推进科研成果与教学资源互通转化、科学研究与学科竞赛贯通融合、科研训练与社会实践协同配合、教育教学与学科竞赛彼此互嵌,全过程、全方位拓展学生的成长空间,有利于推动新文科拔尖创新人才的立体培养以及新文科建设的全面进步。 展开更多
关键词 “科教赛社”多维融合 新文科建设 拔尖创新人才 全过程培养
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Application of New Materials and New Technology for Pavement of Garden Road in Garden Engineering
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作者 SHAOXiaoli 《外文科技期刊数据库(文摘版)自然科学》 2022年第4期036-039,共4页
The main goal of landscape engineering construction is to improve the urban ecological environment, create a good and comfortable living environment for people and improve the quality of life. In order to better carry... The main goal of landscape engineering construction is to improve the urban ecological environment, create a good and comfortable living environment for people and improve the quality of life. In order to better carry out the construction of garden projects and guarantee the ultimate quality and effect of garden construction, in the actual construction stage, it is necessary to comprehensively manage the construction, consider the key elements and mitigation in the construction, and strengthen the attention and improvement of various construction problems. Judging from the current construction situation, it is necessary to make professional selection of pavement materials and strengthen the application of brand-new construction techniques in the construction of garden projects, so as to ensure the environmental protection and energy conservation of the construction, and on a certain basis, to strengthen the effect and quality of garden pavement construction. This paper mainly analyzes the application of new materials and techniques for pavement of garden roads in garden projects, hoping to improve the aesthetic and rationality of garden projects. 展开更多
关键词 garden engineering pavement of garden road new materials new processes applied analysis
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Online single particle measurement of fireworks pollution during Chinese New Year in Nanning 被引量:4
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作者 Jingyan Li Tingting Xu +9 位作者 Xiaohui Lu Hong Chen Sergey A.Nizkorodov Jianmin Chen Xin Yang Zhaoyu Mo Zhiming Chen Huilin Liu Jingying Mao Guiyun Liang 《Journal of Environmental Sciences》 SCIE EI CAS CSCD 2017年第3期184-195,共12页
Time-resolved single-particle measurements were conducted during Chinese New Year in Nanning, China. Firework displays resulted in a burst of SO2, coarse mode, and accumulation mode (100-500 nm) particles. Through s... Time-resolved single-particle measurements were conducted during Chinese New Year in Nanning, China. Firework displays resulted in a burst of SO2, coarse mode, and accumulation mode (100-500 nm) particles. Through single particle mass spectrometry analysis, five different types of particles (fireworks-metal, ash, dust, organic carbon-sulfate (OC-sulfate), biomass burning) with different size distributions were identified as primary emissions from firework displays. The fireworks-related particles accounted for more than 70% of the total analyzed particles during severe firework detonations. The formation of secondary particulate sulfate and nitrate during firework events was investigated on single particle level. An increase of sulfite peak (80SO3) followed by an increase of sulfate peaks (97HSO7+96SO7) in the mass spectra during firework displays indicated the aqueous uptake and oxidation of SO2 on particles. High concentration of gaseous SO2, high relative humidity and high particle loading likely promoted SO2 oxidation. Secondary nitrate formed through gas-phase oxidation of NO2 to nitric acid, followed by the condensation into particles as ammonium nitrate. This study shows that under worm, humid conditions, both primary and secondary aerosols contribute to the particulate air pollution during firework displays. 展开更多
关键词 Chinese new YearFireworksParticle typesSecondary process
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Analysis of Mineralization System and Prediction of New-Type Ore Deposits 被引量:1
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作者 Zhai Yusheng Peng Runmin Deng Jun Wang Jianping Department of Geology and Mineral Resources, China University of Geosciences, Beijing 100083 《Journal of Earth Science》 SCIE CAS CSCD 2000年第2期15-20,共6页
The discovery of new-type ore deposits, an important approach to guarantee the mineral resources supply in the 21st century, often brings about a gigantic increase in the mineral resources reserves. The analysis of mi... The discovery of new-type ore deposits, an important approach to guarantee the mineral resources supply in the 21st century, often brings about a gigantic increase in the mineral resources reserves. The analysis of mineralization system is of great importance to the discovery of new type ore deposits. ① The understanding of the relationship among various ore deposit types within a mineralization system in a region can help us to locate the unknown ore deposit types from the known ore deposit types, evidence that has been proved in the mineral prospecting history of ore belts in the middle and lower reaches of the Yangtze River, China. ② The understanding of the spatial structure of a mineralization system, especially of the vertical zonation, is helpful for the discovery of the concealed ore deposit types. ③ Clarifying the temporal structure of a mineralization system, including the iteration relationship between the mineral deposit types in the mineralization, leads to the location of the missing mineralization chains from the known mineralization chains (mineral deposit type), a method often proved to be effective in the magmatic hydrothermal mineralization system.④ Clarifying the factors restraining the diversity of mineral deposit types in mineralization system leads to the discovery of the potential of new type mineral deposits in relevant region. ⑤ Studying new mineralization setting and new ore forming processes leads to discovery of new type mineral deposit. More probabilities of discovery of new type mineral deposits are present in biogenic mineralization system, deep sea mineralization system, low temperature mineralization system, tectonic mineralization system and superimposed mineralization system. 展开更多
关键词 mineralization system new type mineral deposit new ore forming process from known to unknown concealed ore deposit mineral deposit forecasting.
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New Urbanization Evolution System and Practices in Press Reports 被引量:1
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作者 WANG Jie GUO Xin 《Journal of Landscape Research》 2015年第2期40-42,46,共4页
China has witnessed decades of urbanization, its value, and the plight it is faced with, and development tendency have related and infl uenced social mechanism and system of China. Through adopting media analysis, thi... China has witnessed decades of urbanization, its value, and the plight it is faced with, and development tendency have related and infl uenced social mechanism and system of China. Through adopting media analysis, this paper analyzed reports on "new urbanization" in quality newspapers, so as to provide references for introducing the role of "new urbanization" in the current social transformation, the game-playing relationship and interaction of different social power relation in discourse fi eld, role of social classes in "new urbanization", and their infl uence on the construction and development tendency. 展开更多
关键词 new urbanization Urbanization process Media analysis
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New Combination of Semilate Rice: Yuanliangyou 1000
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作者 Jinhe HU Guoxiang LIU +3 位作者 Qiyun DENG Xiaojing WU Shuwen HE Fei ZHU 《Agricultural Biotechnology》 CAS 2018年第6期74-77,80,共5页
Yuanliangyou 1000 is new combination of semilate rice bred by Yuan S and R900 by Institute of Grain and Oil Crops of Nanchang Academy of Agricultural Science,Yuanshi Seed Industry High Tech Co.,Ltd.and Jiangxi Pusheng... Yuanliangyou 1000 is new combination of semilate rice bred by Yuan S and R900 by Institute of Grain and Oil Crops of Nanchang Academy of Agricultural Science,Yuanshi Seed Industry High Tech Co.,Ltd.and Jiangxi Pusheng Agricultural Development Co.,Ltd.It passed through new variety certification of Jiangxi Province in 2017,and approval number was Ganshendao 20170020,which was suitable for plantation of semilate rice in Jiangxi.In this paper,breeding process,combination characteristic,main cultivation technique and seed production technology of Yuanliangyou 1000 were introduced. 展开更多
关键词 Semilate RICE new COMBINATION Yuanliangyou 1000 BREEDING process
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基于XLNet和多粒度对比学习的新闻主题文本分类方法 被引量:1
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作者 陈敏 王雷春 +2 位作者 徐瑞 史含笑 徐渺 《郑州大学学报(理学版)》 CAS 北大核心 2025年第2期16-23,共8页
新闻主题文本内容简短却含义丰富,传统方法通常只考虑词粒度或句粒度向量中的一种进行研究,未能充分利用新闻主题文本不同粒度向量之间的关联信息。为深入挖掘文本的词向量和句向量间的依赖关系,提出一种基于XLNet和多粒度特征对比学习... 新闻主题文本内容简短却含义丰富,传统方法通常只考虑词粒度或句粒度向量中的一种进行研究,未能充分利用新闻主题文本不同粒度向量之间的关联信息。为深入挖掘文本的词向量和句向量间的依赖关系,提出一种基于XLNet和多粒度特征对比学习的新闻主题分类方法。首先,利用XLNet对新闻主题文本进行特征提取获得文本中词、句粒度的特征表示和潜在空间关系;然后,通过对比学习R-Drop策略生成不同粒度特征的正负样本对,以一定权重对文本的词向量-词向量、词向量-句向量和句向量-句向量进行特征相似度学习,使模型深入挖掘出字符属性和语句属性之间的关联信息,提升模型的表达能力。在THUCNews、Toutiao和SHNews数据集上进行实验,实验结果表明,与基准模型相比,所提方法在准确率和F 1值上都有更好的表现,在三个数据集上的F 1值分别达到了93.88%、90.08%、87.35%,验证了方法的有效性和合理性。 展开更多
关键词 自然语言处理 文本分类 新闻主题 XLNet 对比学习
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