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free vibration of membrane/bounded incompressible fluid

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Applied Mathematics and Mechanics(English Edition) 2012年第9期33卷 1167-1178页

作者： S.TARIVERDILO j.MIRZAPOUR M.SHAHMARDANI G.REZAZADEH Department of Civil Engineering Faculty of EngineeringUrmia UniversityUrmia 15311-57561Iran Department of Mechanical Engineering Faculty of EngineeringUrmia UniversityUrmia 15311-57561Iran

Vibration of a circular membrane in contact with a fluid has extensive applications in industry. The natural vibration frequencies for the asymmetric free vibra- tion of a circular membrane in contact with a bounded incompressible fluid are derived in this paper. Considering small oscillations induced by the membrane vibration in an incompressible and inviscid fluid, the velocity potential function is used to describe the fluid field. Two approaches are used to derive the free vibration frequencies of the sys- tem, which include a variational formulation and an approximate solution employing the Rayleigh quotient method. A good correlation is found between free vibration frequencies evaluated by these methods. finally, the effects of the fluid depth, the mass density, and the radial tension on the free vibration frequencies of the coupled system are investigated.

关键词： Rayleigh quotient asymmetric free vibration membrane variational formulation

＇OBOR＇ and South Asia： Can India and China Cope with the Emerging ＇New Normal＇ in the Region？

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fudan journal of the Humanities and Social Sciences 2017年第2期10卷 161-178页

作者： j. jeganaathan Department of National Security Studies Central University of Jammu Jammu and KashmirIndia fudan University Shanghai China

Ever since President Xi jinping announced the ＇One Belt, One Road＇ project in 2013, more than 66 countries across the continent expressed their interest to be part of this grand project of the century. In South Asia, most of the countries embraced the idea except India. There is no doubt that OBOR is likely to have farreaching implications on South Asian politics, economy and security. China has been engaging in the region through various economic and development projects for last two decades. This has raised serious security and strategic concerns in India. China＇s growing bilateral trade investments and development-oriented connectivity projects in India＇s neighbourhood have been popularly dubbed as China＇s ＇String of Pearl Strategy＇ aimed to contract India＇s sphere of influence in the region. There is a deficit of trust between emerging India and rising China over their interests and intentions. Many observers, however, view OBOR as a game changer at least in South Asia, where this would necessitate re-alignment and re-balancing. But, how does India perceive this project is a matter of serious concern that would shape the nature of implications on South Asia？ In this context, this article examines the impact of OBOR on South Asia Region from sub-regional perspectives and it explores how China can play a constructive role by reconciling its grand strategy with national interests of South Asian countries in order to minimise the adverse impact of OBOR [especially China-Pakistan Economic Corridor （CPEC）] on the peace and security of the region through effective CBMs.

关键词： India and OBOR Sub-regional trade and connectivity South AsiaCPEC India and jammu and Kashmir

Development of Self-Organized Polymeric Lewis Acid-Catalysts for the Zero-Emission Synthesis of 2-Amino Alcohols

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复旦学报（自然科学版） 2005年第5期44卷 678-679页

作者： j. Inanaga Institute for Materials Chemistry and Engineering Kyushu UniversityHakozaki Higashi-ku Fukuoka 812-8581 Japan

β-Amino alcohols are versatile synthetic intermediates for a wide range of biologically active natural and unnatural products. They can also serve as good chiral ligands for some asymmetric metal complex *** nucleophilic ring-opening of epoxides with an amine is one of the most efficient routes to obtain such β-amino alcohols with 1,2-trans stereochemistry. Therefore, various homogeneous catalysts have been developed for this transformation. Meanwhile, the development of efficient heterogeneous catalysts that can be easily prepared, recovered, and reused without losing their activities has currently received much attention from a practical and environmental point of view, and not a few such reusable heterogeneous catalysts (e. g., supported on inorganic materials or insoluble polymers) have been developed[1]. In general, however, they tend to show lower catalytic activities and selectivities compared to the corresponding homogeneous one, and the preparation of them are often tedious.

关键词：酒精二氨基乙醇聚合体异类催化剂有机物

The Category of Modules on an n-Trivial Extension: the Basic Properties

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Algebra Colloquium 2020年第3期27卷 607-620页

作者： Dirar Benkhadra Driss Bennis j.R.Garcia Rozas CeReMAR Center Faculty of Sciences Mohammed V University in RabatRabatMorocco Departamento de Matematicas Universidad de Almeria 04071 AlmenaSpain

In this paper we investigate a categorical aspect of n-trivial extension of a ring by a family of ***,we introduce the right(resp.,left)n-trivial extension of a category by a family of *** other results,projective,injective and flat objects of this category are characterized,and two applications are presented at the end of this *** characterize when an n-trivial extension ring is k-perfect and establish a result on the self-injective dimension of an n-trivial extension ring.

关键词： trivial extension of rings n-trivial extension of abelian categories

Impact of nitrogen doping on growth and hydrogen impurity incorporation of thick nanocrystalline diamond films

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Chinese Physics B 2011年第5期20卷 433-438页

作者：顾利萍唐春玖江学范 j.L.Pinto Department of Physics Jiangsu Key Laboratory for Advanced Functional MaterialsChangshu Institute of Technology Department of Physics I3N(Institute for NanostructuresNanomodelling and Nanofabrication)University of AveiroCampus Universita'rio de Santiago3810-193 AveiroPortugal

A much larger amount of bonded hydrogen was found in thick nanocrystalline diamond （NCD） films produced by only adding 0.24% N2 into 4% CH4/H2 plasma, as compared to the high quality transparent microcrystalline diamond （MCD） films, grown using the same growth parameters except for nitrogen. These experimental results clearly evidence that defect formation and impurity incorporation （for example, N and H） impeding diamond grain growth is the main formation mechanism of NCD upon nitrogen doping and strongly support the model proposed in the literature that nitrogen competes with CHx （x = 1, 2, 3） growth species for adsorption sites.

关键词： thick nanocrystalline diamond films nitrogen doping crystalline quality

EffECT Of Ar PRESSURE ON STRUCTURAL AND ELECTRICAL PROPERTIES Of Cu fILMS DEPOSITED ON GLASS BY DC MAGNETRON SPUTTERING

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Acta Metallurgica Sinica(English Letters) 2002年第1期15卷 39-44页

作者： P. Wu f.P. Wang L.Q. Pan Y. Tian H. Qiu Dept. of Phys. Univ. of Sci. and Technol. Beijing Beijing 100083 China

Cu films with thickness of 630-1300nm were deposited on glass substrates without heating by DC magnetron sputtering in pure Ar gas. Ar pressure was controlled to 0.5, 1.0 and 1.5Pa respectively. The target voltage was fixed at 500V but the target current increased from 200 to 1150mA with Ar pressure increasing. X-ray diffraction, scanning electron microscopy and atomic force microscopy were used to observe the structural characterization of the films. The resistivity of the films was measured using four-point probe technique. At all the Ar pressures, the Cu films have mixture crystalline orientations of [111], [200] and [220] in the direction of the film growth. The film deposited at lower pressure shows more [111] orientation while that deposited at higher pressure has more [220] orientation. The amount of larger grains in the film prepared at 0.5Pa Ar pressure is slightly less than that prepared at 1.0Pa and 1.5Pa Ar pressures. The resistivities of the films prepared at three different Ar pressures represent few differences, about 3-4 times of that of bulk material. Besides the deposition rate increases with Ar pressure because of the increase in target current. The contribution of the bombardment of energetic reflected Argon atoms to these phenomena is discussed.

关键词： Cu film DC magnetron sputtering deposition Ar pressure structure reststivity

The Chronological History and Taxonomic Variation of the Genus Cupressus (Cupressaceae) in India

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云南植物研究 2006年第5期28卷 469-470页

作者： j.Silba Department of Horticulture State University of New YorkFarmingdale N YUSAHonorary Alumni

Recent embryological evidence of studies of seedlings of Cupressus *** with chemotaxonomic studies of heartwood components has demonstrated that Cupressus lusitanica *** indeed originate from the country of *** the mid-sixteenth century,Portuguese merchants established early trade routes between India and *** trade developed from the spice industry confirms Miller’s (1768) original description that Cupressus lusitanica did indeed originate from *** authors suggested that Cupressus lusitanica cultivated in Portugal was introduced from wild populations of Cupressus in ***,this latter theory was never accepted by native botanist in the country of Mexico,including noted botanist *** (1948).In fact,all Cupressus species in India seem to have a different embryology than that of all Cupressus species in Nepal, Bhutan, China and Vietnam (Silba,1994).

关键词： Cupressus Chronological history Taxonomic variation

The information content of financial survey response data

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financial Innovation 2015年第1期1卷 131-150页

作者： j Christopher Westland University of Illinois

Market data for financial studies typically derives from either historical transactions or contemporaneous surveys of sentiment and *** research communities analyzing data from these opposing categories of source data see themselves as distinct,with advantages not shared by the *** research investigates these latter claims in an information theoretic context,and suggests where methods and controls can be *** current research develops a fisher Information metric for Likert scales,and explores the effect of particular survey design decisions or results on the information content.A fisher Information metric outperforms earlier metrics by converging reliably to values that are intuitive in the sense that they suggest that information captured from subjects is fairly *** results of the analysis suggest that varying bias and response dispersion inherent in specific surveys may require increases of sample size by several orders of magnitude to compensate for information loss and in order to derive valid conclusions at a given significance and power of tests.A prioritization of quality of design,and the factors relevant to survey design are presented in the conclusions,and illustrative examples provide insight and guidance to the assessment of information content in a survey.

关键词： financial transactions Information theory Survey Economics Mathematical models

Uptake and transformation of arsenic during the reproductive life stage of Agaricus bisporus and Agaricus campestris

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journal of Environmental Sciences 2016年第11期28卷 140-149页

作者： Michelle M.Nearing Iris Koch Kenneth j.Reimer Environmental Sciences Group Royal Military College of Canada

fruiting bodies from the Agaricus genus have been found to contain non-toxic arsenobetaine（AB） as a major compound. It is unknown whether AB is formed during the vegetative or reproductive life stages of the fungus, or by the surrounding microbial community, but AB＇s structural similarity to glycine betaine has led to the hypothesis that AB may be adventitiously accumulated as an osmolyte. To investigate the potential formation of AB during the reproductive life stage of Agaricus species, growth substrate and fungi were collected during the commercial growth of Agaricus bisporus and analyzed for arsenic speciation using HPLC-ICP-MS. AB was found to be the major arsenic compound in the fungus at the earliest growth stage of fruiting（the primordium）. The growth substrate mainly contained arsenate（As（V））. The distribution of arsenic in an A. bisporus primordium grown on As（V） treated substrate, and in a mature Agaricus campestris fruiting body collected from arsenic contaminated mine tailings, was mapped using two dimensional XAS imaging. The primordium and stalk of the mature fruiting body were both found to be growing around pockets of substrate material containing higher As concentrations, and AB was found exclusively in the fungal tissues. In the mature A. campestris the highest proportion of AB was found in the cap, supporting the AB as an osmolyte hypothesis. The results have allowed us to pinpoint the fungus life stage at which AB formation takes place,namely reproduction, which provides a direction for further research.

关键词： Arsenobetaine Arsenic Agaricus fungi HPLC-ICP-MS XAS imaging