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灰色关联聚类在宇宙射线μ子成像中的应用 被引量:2
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作者 王月 陈宗海 +1 位作者 王红艳 杨宏伟 《核电子学与探测技术》 CAS CSCD 北大核心 2011年第8期871-873,共3页
该工作为宇宙线μ子探测裂变核材料研究中的一部分。宇宙射线μ子成像目标存在粒子数偏少的客观条件,符合灰色系统理论的"小样本"、"贫信息"的特点,首次探索应用灰色关联聚类分析提高宇宙射线μ子成像中对物质区分... 该工作为宇宙线μ子探测裂变核材料研究中的一部分。宇宙射线μ子成像目标存在粒子数偏少的客观条件,符合灰色系统理论的"小样本"、"贫信息"的特点,首次探索应用灰色关联聚类分析提高宇宙射线μ子成像中对物质区分效率的方法。 展开更多
关键词 灰色关联分析 灰色聚类 宇宙射线μ子成像 物质区分
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以学科思想为统领把握解决问题的基本思路——初三化学“碳酸盐的性质和检验”教学探讨
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作者 石英 何彩霞 《教育与装备研究》 2017年第10期29-32,共4页
"初步学会根据某些性质检验和区分一些常见物质"是学生在初三化学学习中需要达成的基本知识和技能。以学科思想方法为统领,依据碳酸盐组成结构与其性质的内在关系,阐述了"利用共性检验一类物质、利用性质差异区分不同物质"的基本思... "初步学会根据某些性质检验和区分一些常见物质"是学生在初三化学学习中需要达成的基本知识和技能。以学科思想方法为统领,依据碳酸盐组成结构与其性质的内在关系,阐述了"利用共性检验一类物质、利用性质差异区分不同物质"的基本思路。以此为指导,就"碳酸盐的性质与检验"一课的主要教学活动设计进行了探讨,力求帮助学生在知识学习的同时获得解决相关问题的思路方法,促进知识的迁移和运用。 展开更多
关键词 碳酸盐的性质与检验 物质的组成与性质 物质的检验与区分 教学设计
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Effects of transport on aerosols over the eastern slope of the Tibetan Plateau:synergistic contribution of Southeast Asia and the Sichuan Basin 被引量:1
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作者 SU Hong-Juan XIN Jin-Yuan +8 位作者 MA Yong-Jing LIU Zirui WEN Tian-Xue WANG Shi-Gong FAN Guang-Zhou LI Wei WANG Lu HE Zhi-Ming WANG Yue-Si 《Atmospheric and Oceanic Science Letters》 CSCD 2018年第5期425-431,共7页
The aerosol optical properties and chemical components of PM2.1(particulate matter with a diameter of 2.1μm or less)were investigated at Mount Gongga on the eastern slope of the Tibetan Plateau from April 2012 to Dec... The aerosol optical properties and chemical components of PM2.1(particulate matter with a diameter of 2.1μm or less)were investigated at Mount Gongga on the eastern slope of the Tibetan Plateau from April 2012 to December 2014.The annual mean aerosol optical depth(AOD)was 0.35±0.23,and the?ngstr?m exponent was 1.0±0.38.The AOD exhibited higher values in summer and winter,but lower values in spring and autumn.Dividing the observational periods into dry and wet seasons,the authors found that the concentrations of K^+,elemental carbon,secondary inorganic aerosols,and primary and secondary organic carbon in the dry(wet)season were 0.29(0.21),0.88(0.60),7.4(4.5),7.5(5.1),and 3.9(12)μg m?3,respectively.Combined with trajectory analysis,the authors found that higher concentrations of K^+,elemental carbon,and primary organic carbon indicated the effects of biomass burning from Southeast Asia during the dry season.However,the oxidation of volatile organic compounds was the main source of aerosols during the wet season,which originated from the Sichuan Basin. 展开更多
关键词 Tibetan Plateau aerosol optical depth aerosol components biomass burning regional transport
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Effects of Row Spacing on Component, Biomass and Energy of Elymus sibiricus L.
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作者 Jinping Liu Minghong You 《Journal of Environmental Science and Engineering(A)》 2013年第10期617-624,共8页
In the study, E. sibiricus L. cv. chuancao No. 2 was allocated to plots in a randomized block design with five row gradients (30, 45, 60, 75 and 90 cm). At the flowering stage, the root, stem, leaf and inflorescence... In the study, E. sibiricus L. cv. chuancao No. 2 was allocated to plots in a randomized block design with five row gradients (30, 45, 60, 75 and 90 cm). At the flowering stage, the root, stem, leaf and inflorescence of population, as well as the quantitative traits of components, biomass structure, accumulation and distribution proportion of energy were measured and analyzed. For different row spacings, there are highly significant differences between total tillers and ratio of fertile tillers per square meter and significant differences among the eustipes length, eustipes number and natural height of each tiller; but there are no significant differences among the leaf length, leaf width and leaf number of each tiller. A significant difference is found between the depth and distribution range of root, inflorescence stalk, and ear number of fertile tillers, and the biomass of leaf, stem, root and inflorescence. The influenced order is stem 〉 leave 〉 root 〉 inflorescence. No significant influence is found among the energy values of single leaf, stem, root and inflorescence; but a significant influence is found among the energy accumulation of the leaf, stem, root and inflorescence with the effect degree being stem 〉 leaf 〉 inflorescence 〉 root. Significant differences are also found among the energy distribution of each component with the order of leaf〉 stem 〉 inflorescence 〉 root. 展开更多
关键词 Biomass structure COMPONENT Elymus sibiricus L. ENERGY row space.
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Backfilling technology and strata behaviors in fully mechanized coal mining working face 被引量:55
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作者 Zhang Qiang Zhang Jixiong +1 位作者 Huang Yanli Ju Feng 《International Journal of Mining Science and Technology》 2012年第2期151-157,共7页
Based on the principle of fully mechanized backflling and coal mining technology and combined with the Xingtai Coal Mine conditions, we mainly optimized the coal mining equipment and adjusted the coal mining method in... Based on the principle of fully mechanized backflling and coal mining technology and combined with the Xingtai Coal Mine conditions, we mainly optimized the coal mining equipment and adjusted the coal mining method in the Xingtai Coal Mine 7606 working face for implementation this technology. Firstly, we define the practical backfilling process as the "(from backfilling scraper conveyor's) head to tail back- filling, step by step swinging up of the tamping arm, gradual compacting, moving formed backfilling scra- per conveyor when the second tamping arm cannot pass and connecting the immediate roof by back material push front material movement". Meanwhile, the stress changes of backfill body in coal mined out area was monitored by stress sensors, and the roof caving law was analyzed by monitoring the dynamic subsidence of -210 west roadway of this face. The site tests results show that using this new backfilling and coal mining integrated technology, the production capacity in the 7606 working face can reach to 283,000 ton a year, and 282,000 ton of solid materials (waste and fly ash) is backfilled, which meets the needs of high production and efficiency. The goaf was compactly backfilled with solid material and the strata behavior was quite desirable, with an actual maximum vertical stress of the backfill body of 5.5 MPa. Backfill body control the movement of overburden within a certain range, and there is no col- lapses of major areas in the overlying strata upon backfilled gob. The maximum subsidence and speed were 231 mm and 15.75 mm/d respectively, which proved the practical significance of this integrated technology. 展开更多
关键词 Fully mechanized backfilling and coalmining technologyHydraulic supportFormed backfilling scraper conveyorBackfilling technologyStrata behaviors
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Urban Integrated Activity Zone (UIAZ) in Shanghai
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作者 Shunyao Zhang Yi Chen 《Sociology Study》 2014年第11期965-973,共9页
Urban integrated activity zone (UIAZ) refers to multi-functional area that can provide various services. Integrated activity zone (IAZ), which is based on the existing financial district and Central Business Distr... Urban integrated activity zone (UIAZ) refers to multi-functional area that can provide various services. Integrated activity zone (IAZ), which is based on the existing financial district and Central Business District (CBD), often weakens administrative boundaries and changes the original single functional partition. It emphasizes the mixture of different functions and the vitality of the central area. The construction of IAZ is different from the simple space construction of economy and material production. IAZ emphasizes the participation of city dwellers in urban renewal process. Shanghai IAZs are those vigorous public activity centers in Shanghai. ]ust like those active cells, IAZs in Shanghai are to inspire and improve the comprehensive competitiveness and vitality of the city at macro, intermediate, and micro level, they are the public places in which urban cultural life takes place, develops, and precipitates. This paper provides broad and profound presentation on IAZ structure planning in Shanghai: mix-used function, multi-dimensions scale, people oriented development (POD) transportation, commercial development, and city form vitality. This paper provides not only qualitative analysis, but also makes a serious attempt to quantify the result and statement. 展开更多
关键词 Integrated activity zone (IAZ) mix-used function city vitality
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Carbon and nitrogen isotopes analysis and sources of organic matter in the upper reaches of the Chaobai River near Beijing,China 被引量:8
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作者 LU FengYun LIU ZhuQing JI HongBing 《Science China Earth Sciences》 SCIE EI CAS 2013年第2期217-227,共11页
The carbon and nitrogen isotopes in the surface sediments,plants,and soil in the upper reaches of the Chaobai River have been researched.The results showed 27.75‰-21.58‰ and 1.32‰-6.74‰ for carbon and nitrogen iso... The carbon and nitrogen isotopes in the surface sediments,plants,and soil in the upper reaches of the Chaobai River have been researched.The results showed 27.75‰-21.58‰ and 1.32‰-6.74‰ for carbon and nitrogen isotopic ratios in the surface sediments,respectively.The sources of sedimentary organic matter in this area are soil organic matter,aquatic vascular plants,and riverine plankton,respectively,and a significant contributor to sediment in the Chaohe River,the Baihe River,and the Miyun Reservoir areas is soil organic matter.Furthermore,part of sedimentary organic matter in the Miyun Reservoir is attributed to the input from the Chaohe River and the Baihe River,the other is from C4 vegetation growing around individual point stations at the Miyun Reservoir.Compared with the situation in Hebei Province,the contribution of soil organic matter decreased significantly and river plankton and aquatic vascular plants increased significantly in Beijing municipal areas.This study reveals that the source of organic matter has a close relationship with the soil erosion. 展开更多
关键词 carbon isotopes nitrogen isotopes organic matter Chaobai River material source
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Study of Substrate and Physico-Chemical Base Classification of the Rivers of Nepal
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作者 JHA Bibhuti Ranjan WAIDBACHER Herwig +1 位作者 SHARMA Subodh STRAIF Michael 《Geo-Spatial Information Science》 2010年第1期70-76,共7页
The rivers in Nepal are classified in terms of geographical regions but a more scientific classification such as on the ba-sis of morphology is clearly lacking. This study was done in 9 rivers namely Jhikhukhola of th... The rivers in Nepal are classified in terms of geographical regions but a more scientific classification such as on the ba-sis of morphology is clearly lacking. This study was done in 9 rivers namely Jhikhukhola of the Koshi system, Aandhikhola, Arungkhola, East Rapti, Karrakhola, Seti and main channel Narayani of the Gandaki system, and two independent systems within Nepal, Bagmati and Tinau. Among the morphologies, river bed or the substratum was taken as the main variable for the analysis which was categorized into 7 types as rocks, boulders, cobbles, pebbles, gravels, sand and silt. There were 23 sampling sites each with 2 stretches of around 100m in those rivers. The data were taken as a percentage, and to avoid biases it was observed visually by the same person for a complete year in every season. With 23 sites each with 2 stretches and 4 replicates corresponding to 4 seasons, there are altogether 184 observations, each termed as a case, that constitute this work. Canonical Discrimination Analysis (CDA) which is most suitable when the data pool is huge was applied to see if the rivers studied distinguish themselves in terms of its morphology. The result was remarkably successful and was close to the established regional classification of the rivers. This kind of river classification has great application in the utilization, conservation and restoration of the most important natural re-source of the country. 展开更多
关键词 Nepal rivers morphology physico-chemical parameter river classification
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