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Growth Habit of the Basic Oxysulfate Magnesium Whisker 被引量:2
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作者 吴健松 高义民 《Journal of Wuhan University of Technology(Materials Science)》 SCIE EI CAS 2016年第2期248-253,共6页
The growth habit of the basic magnesium oxysulfate whisker was investigated based on the theoreticalmodelof anion coordination polyhedron growth units.It is found that typicalbasic magnesium oxysulfate whisker growth ... The growth habit of the basic magnesium oxysulfate whisker was investigated based on the theoreticalmodelof anion coordination polyhedron growth units.It is found that typicalbasic magnesium oxysulfate whisker growth is consistent with anion tetrahedralcoordination incorporation rules.The growth units of basic magnesium oxysulfate whiskers are [Mg-(OH)_4]^(2-) and HSO_4^-.[Mg-(OH)_4]^(2-) is the favorable growth unit and whisker growth is in the direction of the [Mg-(OH)_4]^(2-) combination.A plurality of [Mg-(OH)_4]^(2-) s combine and become a larger dimensionalgrowth unit in a one-dimensionaldirection.Then HSO_4^- and larger dimensionalgrowth units connect as basic magnesium sulfate whiskers,according to the structuralcharacteristics of the basic magnesium sulfate whisker,which can guide the synthesis of magnesium hydroxide whisker. 展开更多
关键词 model of anion coordination polyhedron growth units basic magnesium oxysulfate whisker growth habit crystal morphology
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A Landscape Pattern Characterization Method Based on the Natural Complex: A Case Study of Songhua River Basin, China
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作者 TANG Jing YU Lingxue +2 位作者 ZHANG Xing LI Ying YANG Gao 《Chinese Geographical Science》 2025年第3期492-509,共18页
The‘human-land relationship’has long been a central topic in geography,ecology,and social sciences.And dynamic monit-oring of the land use/cover change(LUCC)and landscape pattern studies of land use provide essentia... The‘human-land relationship’has long been a central topic in geography,ecology,and social sciences.And dynamic monit-oring of the land use/cover change(LUCC)and landscape pattern studies of land use provide essential theoretical support for this field.On the basis of physicogeographical regionalization and landscape ecology theory,this study proposed a method for characterizing land-scape pattern by using the minmium natural complex as the basic evaluation unit,constructing a four-level classification framework that included natural area,landscape region,landscape subregion,and landscape group.The method was tested in the Songhua River Basin,China,and the results revealed that:(1)the landscape pattern characterization in the Songhua River Basin validated the feasibility of the proposed method,and the use of the minimum natural complex as the basic measurement unit for landscape pattern characterization be-nefited research in this field.(2)The multiscale landscape pattern characterization system,which was framed around natural area,land-scape region,landscape subregion,and landscape group,accurately reflected the spatial heterogeneity of the physical geographic envir-onment and the impact of human activities on the landscape pattern in the Songhua River Basin.The nature-dominated landscape region was mainly concentrated in high-altitude mountainous and hilly areas,the human-dominated landscape region was located on plains and platforms,and the human-land interaction landscape region exhibited a landscape pattern that is closely related to natural factors such as temperature,precipitation,and soil.(3)The proposed method not only revealed the complex interactions between the physical geograph-ic environment and human activities but also provided scientific support for land use planning and ecological environment management.Future research should incorporate higher-resolution data and socioeconomic factors to further explore the dynamic changes in land-scape patterns and their impacts on the regional ecological environment. 展开更多
关键词 human-land relationship minimum natural complex basic evaluation unit landscape pattern characterization Songhua River Basin China
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Spatial Narrative and The Kite Runner
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作者 张金艳 《海外英语》 2017年第20期188-189,共2页
This article analyzes The Kite Runner with the help of spactial narrative. The novel will be analyzed from three angles—the function of spatial narrative, the basic unit of spatial narrative, the periphery of spatial... This article analyzes The Kite Runner with the help of spactial narrative. The novel will be analyzed from three angles—the function of spatial narrative, the basic unit of spatial narrative, the periphery of spatial narrative and the overall effect presented in the novel by using these narrative techniques. 展开更多
关键词 Spatial Narrative Contemporary English Novel The Kite Runner function of Spatial Narrative the basic unit of Spatial Narrative the periphery of Spatial Narrative
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Design and analysis of a truss deployable antenna mechanism based on a 3UU-3URU unit 被引量:7
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作者 Yundou XU Jinwei GUO +3 位作者 Luyao GUO Wenlan LIU Jiantao YAO Yongsheng ZHAO 《Chinese Journal of Aeronautics》 SCIE EI CAS CSCD 2019年第12期2743-2754,共12页
Space deployable structures with large calibers, high accuracy, and large folding ratios are indispensable equipment in the aerospace field. Given that the single-DOF 3 RR-3 RRR deployable unit cannot be fully folded,... Space deployable structures with large calibers, high accuracy, and large folding ratios are indispensable equipment in the aerospace field. Given that the single-DOF 3 RR-3 RRR deployable unit cannot be fully folded, this study proposes a 3 UU-3 URU deployable unit with two kinds of DOF: folding movement and orientation adjustment. First, based on the G-K formula, the DOF of the 3 UU-3 URU unit is analyzed. Then, the 3 UU-3 URU unit is used to construct a deployable truss antenna with a curved surface, and the DOF of the whole deployable antenna containing multiple 3 UU-3 URU units is calculated. The structural design of a deployable antenna with two loops is carried out with specific parameters and geometric relations. Next, a DOF simulation of a basic combination unit composed of three 3 UU-3 URU units is performed. Finally, a prototype of the basic combination unit is manufactured, and the DOF of the mechanism is experimentally verified. 展开更多
关键词 basic combination unit Degree of freedom(DOF) Deployable truss antenna Simulation analysis Structural design
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Experimentation of a 1-pixel bit reconfigurable ternary optical processor 被引量:1
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作者 王宏健 金翊 +1 位作者 欧阳山 周裕 《Journal of Shanghai University(English Edition)》 CAS 2011年第5期430-436,共7页
A detailed experiment of 1-pixel bit reconfigurable ternary optical processor (TOP) is proposed in the paper. 42 basic operation units (BOUs) and 28 typical logic operators of the TOP are realized in the experimen... A detailed experiment of 1-pixel bit reconfigurable ternary optical processor (TOP) is proposed in the paper. 42 basic operation units (BOUs) and 28 typical logic operators of the TOP are realized in the experiment. Results of the test cases elaborately cover the every combination of BOUs and all the nine inputs of ternary processor. Both the experiment process and results analysis are given in this paper. The experimental results demonstrate that the theory of reconfiguring a TOP is valid and that the reconfiguration circuitry is effective. 展开更多
关键词 ternary optical processor (TOP) decrease-radix design basic operation units (BOUs) RECONFIGURABILITY recon figuration circuitry
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Comprehensive Drafts of Woven Fabrics
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作者 Oghale Omojuwouvie Okpu Ojeo Oluwafunmilayo Loromeke 《Journal of Textile Science and Technology》 2020年第3期130-143,共14页
The crux of this paper is based on the pattern drafting of woven fabrics. It is necessary because many textile designers or weavers cannot generate and develop their personal pattern drafts for weaving. It is obvious ... The crux of this paper is based on the pattern drafting of woven fabrics. It is necessary because many textile designers or weavers cannot generate and develop their personal pattern drafts for weaving. It is obvious that they mainly copy other people’s designs to weave. This paper therefore has provided an easy and simple way to learn, focus and develop their original designs to weave. The practical production method is used to create, generate and develop the pattern drafts in this paper. The paper focuses on the components of the pattern draft which will surely help to forecast and have a view of the appearance of the design before it is woven on the cloth. In conclusion, the weaver will be able to record and document his/her original works for posterity. 展开更多
关键词 Pattern Draft basic Unit Lifting Plan Threading and Treadling Drafts
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A preliminary analysis of multi-genre
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作者 REN Guo-wei 《Sino-US English Teaching》 2010年第12期38-41,共4页
The paper attempts to make a preliminary exploration on the analytic framework of multi-generic phenomenon. Three strata have been identified in a multi-generic analytical framework and basic analytic unit for each st... The paper attempts to make a preliminary exploration on the analytic framework of multi-generic phenomenon. Three strata have been identified in a multi-generic analytical framework and basic analytic unit for each stratum has been well-established. Textual structure is identified as the basic analytic unit for texts, generic structural potential for member genres and schematic structure for multi-generic integration. Each basic analytic unit is responsible for generating the corresponding concrete form of representation. 展开更多
关键词 multi-genre three-stratum hierarchical framework basic analytic unit
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Study on the Route and Method of Natural Resources Investigation —— A Case Study of Xuzhou City
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作者 SHANBingying ZHANGXiao 《外文科技期刊数据库(文摘版)自然科学》 2022年第4期189-193,共5页
The survey on natural resources can better reflect the national conditions and strength. In order to study and formulate the natural resources survey technical route and survey method that are in line with the actual ... The survey on natural resources can better reflect the national conditions and strength. In order to study and formulate the natural resources survey technical route and survey method that are in line with the actual situation, first of all, a comparative analysis is made on the unification of natural resources ownership and survey to find out the similarities and differences between the two tasks, so as to determine the natural resources survey technical route. Then, referring to the technical characteristics of the basic units determined in the unification of natural resources ownership, the survey unit and the survey patch are proposed as the basic units of natural resources survey work, and the corresponding definitions and division methods are given. Finally, relying on the natural resources survey work in Xuzhou urban area, the rationality of the survey unit and the survey patch is analyzed, which can provide a reference for the further development of natural resources survey work. 展开更多
关键词 natural resources survey technical route basic unit survey module investigating plaque
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Research on the Contents and Improvement Strategies of Animal Epidemic Prevention at Grass-roots Level
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作者 LI Chundong ZHANG Baocang 《外文科技期刊数据库(文摘版)自然科学》 2021年第11期008-010,共5页
The development of animal epidemic prevention at the grass-roots level is of great significance to the development of animal husbandry and the safety of animal products in the region. The occurrence of animal epidemic... The development of animal epidemic prevention at the grass-roots level is of great significance to the development of animal husbandry and the safety of animal products in the region. The occurrence of animal epidemic events in recent years has profoundly reflected the shortcomings of the grass-roots animal epidemic prevention system and laid the general tone for grass-roots units to strengthen animal epidemic prevention management and standardize animal epidemic prevention procedures. This paper focuses on the grass-roots animal epidemic prevention work, analyzes the basic content of animal epidemic prevention and the improvement strategies of animal epidemic prevention in the new era for reference. 展开更多
关键词 basic unit animal epidemic prevention epidemic prevention content perfect strategy
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Ba_(2)B_(9)O_(13)F_(4)·BF_(4):first fluorooxoborate with unprecedented infinite [B_(18)O_(26)F_(8)] tubes and deep-ultraviolet cutoff edge 被引量:1
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作者 Huan Pei Xuefei Wang +3 位作者 Jie Zhang Fangfang Zhang Zhihua Yang Shilie Pan 《Science China Chemistry》 SCIE EI CAS CSCD 2023年第4期1073-1077,共5页
Fluorooxoborate has emerged as a promising system for exploring optical materials due to their rich structural chemistry and physicochemical properties,yet so far not fully studied.Herein,we report a new fluorooxobora... Fluorooxoborate has emerged as a promising system for exploring optical materials due to their rich structural chemistry and physicochemical properties,yet so far not fully studied.Herein,we report a new fluorooxoborate,Ba_(2)B_(9)O_(13)F_(4)·BF_(4),which contains the greatest variety of structural basic units,[BO_(3)],[BO_(2)F_(2)],[BO_(3)F],and[BF_(4)],and exhibits unprecedented 1D infinite[B_(18)O_(26)F_(8)]tubes.The unique structure avoids the dangling bonds caused by terminal oxygens,which is beneficial to the large bandgap and deep-ultraviolet cutoff edge.This article expands the crystal structure of fluorooxoborates and contributes to the exploration of deep-ultraviolet optical materials in fluorooxoborate systems. 展开更多
关键词 fluorooxoborate unprecedented infinite tubes four basic units deep-ultraviolet
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