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Phase behavior of rotationally asymmetric Brownian kites containing 90°internal angles

Chinese Physics B 2021年第12期30卷 467-472页

作者： Huaqing Liu Yiwu Zong Zhanglin Hou thomas g.Mason Kun Zhao Key Laboratory of Systems Bioengineering(Ministry of Education) School of Chemical Engineering and TechnologyTianjin UniversityTianjin 300072China Wenzhou Institute University of Chinese Academy of SciencesWenzhou 325001China Department of Physics and Astronomy University of California-Los AngelesLos AngelesCA 90095USA Department of Chemistry and Biochemistry University of California-Los AngelesLos AngelesCA 90095USA Physics Department Tianjin UniversityTianjin 300072China

Previous Monte Carlo simulations have shown that ordered tetratic phases can emerge in a dense two-dimensional Brownian system of rotationally asymmetric hard kites having 90°internal ***,there have been no experimental investigations yet to compare with these simulation ***,we have fabricated two types of micron-sized kites having internal angles of 72°-90°-108°-90°and 72°-99°-90°-99°,respectively,and we have experimentally studied their phase behavior in two-dimensional *** and in contrast to the Monte Carlo simulations,the experimental results show a phase sequence of isotropic fluid-hexagonal rotator crystal-square crystal as the area fractionφA increases for both types of *** observed square crystal displays not only a quasi-long-range translational order but also(quasi-)long-range 4-fold bond-and molecular-orientational order;these characteristics confirm that tetratic order can emerge even in dense Brownian systems of rotationally asymmetric particles.A model based on local polymorphic configurations(LPCs)is proposed to understand the origin of the square lattice order in these dense kite *** results in this study provide a new route to realize custom-designed self-assembly of colloids by controlling LPCs.

关键词： tetratic order colloidal kites two-dimentional system phase behavior

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Brownian motion and thermophoresis effects on unsteady stagnation point flow of Eyring-Powell nanofluid: a galerkin approach

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Communications in theoretical Physics 2020年第12期72卷 71-82页

作者： Z H Khan M Usman t Zubair M Hamid R U Haq State Key Laboratory of Hydraulics and Mountain River Engineering College of Water Resource and HydropowerSichuan UniversityChengdu610065China BIC-ESAt College of EngineeringPeking UniversityBeijing 100871China State Key Laboratory for turbulence and Complex Systems Department of Mechanics and Engineering SciencePeking UniversityBeijing 100871China Institute of Ocean Research Peking UniversityBeijing 100871China School of Mathematical Sciences Peking UniversityBeijing 100871China Department of Mechanics and Engineering Science Fudan UniversityShanghai 200433China Department of Electrical Engineering Bahria UniversityIslamabad CampusIslamabad 44000Pakistan

this article concerns the analysis of an unsteady stagnation point flow of Eyring–Powell nanofluid over a stretching *** influence of thermophoresis and Brownian motion is also considered in transport *** nonlinear ODE set is obtained from the governing nonlinear equations via suitable *** numerical experiments are performed using the galerkin scheme.A tabular form comparison analysis of outcomes attained via the galerkin approach and numerical scheme(RK-4)is available to show the credibility of the galerkin *** numerical exploration is carried out for various governing parameters,namely,Brownian motion,steadiness,thermophoresis,stretching ratio,velocity slip,concentration slip,thermal slip,and fluid parameters,and Hartmann,Prandtl and Schmidt *** velocity of fluid enhances with an increase in fluid and magnetic parameters for the case of opposing,but the behavior is reversed for assisting *** Brownian motion and thermophoresis parameters cause an increase in temperature for both cases(assisting and opposing).the Brownian motion parameter provides a drop-in concentration while an increase is noticed for the thermophoresis *** the outcomes and the behavior of emerging parameters are illustrated *** comparison analysis and graphical plots endorse the appropriateness of the galerkin *** is concluded that said method could be extended to other problems of a complex nature.

关键词： Eyring-Powell fluid stagnation point flow Brownian motion and thermophoresis galerkin method

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Sustainable intensification of African agriculture:a necessity,but not yet a reality

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Frontiers of Agricultural Science and Engineering 2020年第4期7卷 383-389页

作者： Bruno gÉRARD International Maize and Wheat Improvement Center(CIMMYt) Texcoco 56237Mexico

After decades of well-intentioned and professional research for development,agriculture in sub-Saharan Africa is still dominated by low-input,subsistence food crop production on small,rainfed land holdings using hand *** are the drivers and constraints to development in African agriculture,and how can the region intensify farming in economical and environmentally sustainable ways to satisfy its rapidly rising and shifting food demands?

关键词： Sustainable agriculture shifting

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Region-based classification of PolSAR data using radial basis kernel functions with stochastic distances

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International Journal of Digital Earth 2019年第6期12卷 699-719页

作者： Rogerio g.Negri Alejandro C.Frery Wagner B.Silva tatiana S.g.Mendes Luciano V.Dutra UNESP-Universidade Estadual Paulista ICT-Instituto de Ciencia e TecnologiaSão Jose dos CamposBrazil LaCCAN-Laboratorio de de Computacao Cientifica e Analise Numerica UFAL-Universidade Federal de AlagoasMaceioBrazil Secao de Ensino de Engenharia Cartografica IME-Instituto Militar de EngenhariaRio de JaneiroBrazil DPI-Divisao de Processamento de Imagens INPE-Instituto Nacional de Pesquisas EspaciaisSao Jose dos CamposBrazil

Region-based classification of PolSAR data can be effectively performed by seeking for the assignment that minimizes a distance between prototypes and *** et al.[“Classification of segments in PolSAR imagery by minimum stochastic distances between wishart distributions.”IEEE Journal of Selected topics in Applied Earth Observations and Remote Sensing 6(3):1263–1273]used stochastic distances between complex multivariate Wishart models which,differently from other measures,are computationally *** this work we assess the robustness of such approach with respect to errors in the training stage,and propose an extension that alleviates such *** introduce robustness in the process by incorporating a combination of radial basis kernel functions and stochastic distances with Support Vector Machines(SVM).We consider several stochastic distances between Wishart:Bhatacharyya,Kullback-Leibler,Chi-Square,Rényi,and *** perform two case studies with PolSAR images,both simulated and from actual sensors,and different classification scenarios to compare the performance of Minimum Distance and SVM classification *** this,we model the situation of imperfect training *** show that SVM with the proposed kernel functions achieves better performance with respect to Minimum Distance,at the expense of more computational resources and the need of parameter *** and data are provided for reproducibility.

关键词： PolSAR image classification stochastic distance minimum distance classifier SVM

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Phase selection rules for complex multi-component alloys with equiatomic or close-to-equiatomic compositions

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自然杂志 2013年第2期35卷 85-96页

作者： gUO Sheng LIU Chain t NationalAcademy of Engineering Center ofAdvanced Structural Materials Department of Mechanical and Biomedical Engineering College of Science and Engineering City University of Hong Kong Kowloon

Alloying greatly expands the amount of available materials beyond the naturally existing ones, and more importantly offers the material scientists opportunities to initiatively control the composition-structure-property relationship in materials. Since commonly used metallic materials are mostly multi-component alloys, the know-how of alloying through compositional control, certainly plays a critical role in designing materials with desired structure and properties. However, alloying in multi-component alloys is an extremely complicated issue, as the alloyed products could be the amorphous phase, various solid solutions and intermetallic compounds containing two or more alloy components. By narrowing down the scope of the multi-component alloys to those with equiatomic or close-to-equiatomic compositions only, and also aiming at framing out the rules that govern the phase selection upon alloying in multi-component alloys in a broad sense, we have identified here a simple and easily executable two-parameter scheme that can effectively predict the formation of the amorphous phase, solid solutions and intermetallic compounds, in multi-component alloys, simply from the given alloy compositions. We believe this scheme reveals a clear physical scenario governing the phase selection in multi-component alloys, helps to simplify the alloy design, and benefits the future development of advanced metallic alloys like bulk metallic glasses and high entropy alloys.

关键词：材料合金化结构特性金属化合物

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First testing of an AUV mission planning and guidance system for water quality monitoring and fish behavior observation in net cage fish farming

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Information Processing in Agriculture 2014年第2期1卷 131-140页

作者： D.Karimanzira M.Jacobi t.Pfuetzenreuter t.Rauschenbach M.Eichhorn R.taubert C.Ament Fraunhofer Advanced System technology(ASt) Am Vogelherd 5098693 IlmenauGermany technical University Ilmenau Helmholtzplatz 598693 IlmenauGermany

Recently,underwater vehicles have become low cost,reliable and affordable platforms for performing various underwater *** many aquaculture systems are closed with no harmful output,open net cage fish farms and land-based fish farms can discharge significant amounts of wastewater containing nutrients,chemicals,and pharmaceuticals that impact on the surrounding *** aquaculture development has often occurred outside a regulatory framework,government oversight is increasingly common at both the seafood quality control level,and at baseline initiatives addressing the basic problem of pollution generated by culture operations,*** European marine and maritime *** requires regular,sustainable and cost-effective monitoring of the water *** monitoring needs devices to detect the water quality in a large sea area at different depths in real *** paper presents a concept for a guidance system for a carrier(an autonomous underwater vehicle)of such devices for the automated detection and analysis of water quality parameters.

关键词： Autonomous underwater vehicle Water quality monitoring Vehicle guidance

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the Rationale for Reviewing Current Concepts of Urban Planning and Developing New Ones in India

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Built Heritage 2017年第3期1卷 34-43页

作者： A.g.Krishna Menon Departments of Architecture and Urban Design School of Planning and ArchitectureNew DelhiIndia

Urban planning in India is heir to a colonial paradigm that imposed practices developed from the experiences of Western urbanisation to the local Indian *** paper suggests that this paradigm exacerbates the complex problems of contemporary urbanisation,but there is little attempt among Indian urban planners to acknowledge and address the consequences of their colonial *** forces of globalisation are reinforcing this postcolonial intellectual malaise by reposing greater faith in capital-and technology-intensive solutions to solve problems instead of reforming the inherited processes of urban *** paper argues that the nascent field of urban conservation in India offers the potential to review the dominant paradigms of urban planning and develop more context-specific and appropriate strategies for tackling the problems of Indian urbanisation.

关键词： historic space historic metropolitan context evolution reflection

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Disposal and Use of Sewage on Agricultural Lands in Pakistan: A Review

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Pedosphere 2010年第1期20卷 23-34页

作者： g. MURtAZA A. gHAFOOR M. QADIR g. OWENS M. A. AZIZ M. H. ZIA SAIFULLAH Institute of Soil and Environmental Sciences University of AgricultureFaisalabad-38040 (Pakistan) Centre for Environmental Risk Assessment and Remediation University of South Australia International Centre for Agricultural Research in the Dry Areas (ICARDA) International Water Management Institute (IWMI) technical Services Department Fauji Fertilizer Company Ltd.

Raw sewage is widely used on agricultural soils in urban areas of developing countries to meet water shortages. Although it is a good source of plant nutrients, such sewage also increases the heavy metal load to soils, which may impact the food chain. Management options for sewage contaminated soils includes addition of nontoxic compounds such as lime, calcium sulfate and organic matter, which form insoluble metal complexes, thus reducing metal phytoavailability to plants. In this paper we review the variation in irrigation quality of sewage at different sites and its impact on the quality of soils and vegetables. Although quality of sewage was highly variable at source, yet the effluent from food industries was relatively safe for irrigation. In comparison effluent samples collected from textile, dyeing, calendaring, steel industry, hospitals and clinical laboratories, foundries and tanneries were hazardous with respect to soluble salts, sodium adsorption ratio and heavy metals like zinc, copper, iron, manganese, nickel, cobalt and cadmium. the sewage quality in main drains was better than that at the industry outlet, but was still not safe for irrigation. In general, higher accumulation of metals in fruits and vegetable roots was recorded compared to that in plant leaves, Edible parts of vegetables （fruits and/or leaves） accumulated metals more than the permissible limits despite the soils contained ammonium bicarbonate diethylenetriaminepentaacetie acid extractable metals within a safe range. In either case further scientific investigations are needed to ensure safe management strategies. Cadmium appeared to be the most threatening metal especially in leafy vegetables. It is advisable to avoid leafy vegetables cultivation in sewage irrigated areas everywhere to restrict its entry into food chain.

关键词： contamination heavy metals irrigation soil quality vegetables

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A Review of Environmental Sociology and the Sociology of Natural Resources:Insights for the Development of Environmental Sociology in China

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Chinese Journal of Population,Resources and Environment 2009年第4期7卷 25-31页

作者： Courtney g.Flint Department of Natural Resources and Environmental Sciences University of Illinois at Urbana-ChampaignS409 Turner HallMC-0471102 S.Goodwin AvenueUrbanaIL 61801United States

Environmental sociology and the sociology of natural resources are two key subdisciplines of the sociological study on the interactions between nature and human *** discussion on the relationships of these two fields has largely focused on their distinctions and synthesis in western(particularly American) *** sociology emerged as an important sociological subdiscipline in China in the early 1990s and is under vigorous disciplinary construction at *** contrast,the sociology of natural resources is still a novel term for most Chinese *** article provides a systematic review of recent literature on the relationships between environmental and natural resource sociologies,which should provide important implications for the further development of environmental sociology in China.

关键词： environmental sociology sociology of natural resources distinctions synthesis transdisciplinarity

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Low-Frequency Dependence of Conductivity and Dielectric Properties of Polyaniline/ZnFe_(2)O_(4) Nanocomposites

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Chinese Physics Letters 2011年第11期28卷 218-221页

作者： g.D.Prasanna H.S.Jayanna Ashok R Lamani M.L.Dinesha C.S.Naveen g.J.Shankaramurthy Department of Pg Studies and Research in Physics Kuvempu UniversityShankarghatta-577451KarnatakaIndia Bapuji Institute of Engineering and technology Davangere-577004KarnatakaIndia

Conducting polyaniline/ZnFe_(2)O_(4) nanocomposites are synthesized by using a simple and inexpensive one-step in-situ polymerization method in the presence of ZnFe2O4 *** structural,morphological and electrical properties of the samples are characterized by x-ray diffraction,Fourier transform infrared spectra and scanning electron *** results reveal the formation of polyaniline/ZnFe2O4 *** morphology of these samples is studied by scanning electron ***,the ac conductivity(σac)of these composites is investigated in the frequency range of 1 kHz–10 *** presence of polarons and bipolarons are responsible for the frequency dependence of ac conductivity in these *** ac conductivity is found to be constant up to 1MHz and thereafter it increases *** ac conductivity of 0.695 S・cm^(−1) at room temperature is observed as the maxima for the polyaniline with 40wt%of the ZnFe2O4 nanocomposite.

关键词： composites ZnFe2O4 conductivity

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