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ELECTROHYDRODYnAMIC DISPERSIOn OF DEFORMABLE AEROSOLS In THE PRESEnCE OF An ELECTRIC FIELD AnD CHEMICAL REACTIOn USIng TAYLOR DISPERSIOn MODEL

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Journal of Hydrodynamics 2011年第2期23卷 247-257页

作者： RUDRAIAH n. DEVARAJU n. ng Chiu-On UGC-CAS in Fluid Mechanics Department of Mathematics Bangalore University Bangalore-560 001 India National Research Institute for Applied Mathematics (NRIAM) Bangalore-560 070 India Department of Mechanical Engineering The University of Hong Kong

Under the effects of electric field and chemical reaction, the problem of dispersion of aerosols in a poorly conducting fluid in a channel is solved analytically using the mixture theory together with a regular perturbation technique. It is shown that the aerosols are dispersed relative to a plane moving with the mean speed of atmospheric fluid as well as the mean speed of agglomeration of aerosol with a relative diffusion coefficient, called the Taylor dispersion coefficient. This coefficient is numerically computed and the results reveal that it increases with an increase in the electric number, but decreases with increasing porous parameter. The physical explanations for the phenomena are given in this article.

关键词： dispersion aerosols electrohydrodynamics mixture theory

A transcription assay for EwS oncoproteins in Xenopus oocytes

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Protein & Cell 2010年第10期1卷 927-934页

作者： King Pan ng Felix Cheung Kevin A.w.Lee Department of Biology The Hong Kong University of Science and TechnologyClear Water BayKowloon Hong KongChina

Aberrant chromosomal fusion of the Ew.ng's sarcoma oncogene(EwS)to several different cellular partners produces the Ew.ng's family of oncoproteins(EwSfusion-proteins,EFPs)and associated tumors(EFTs).EFPs are potent transcriptional activators,dependent on the n-terminal region of EwS(the EwS-activationdomain,EAD)and this function is thought to be central to EFT oncogenesis and *** EFPs are promising therapeutic targets,but detailed molecular studies will be pivotal for exploring this *** studies have so far largely been restricted to intact mammalian cells while recent evidence has indicated that a mammalian cell-free transcription system may not support bona fide EAD ***,the lack of manipulatable assays for the EAD presents a significant barrier to *** Xenopus laevis oocytes we describe a plasmid-based micro-injection assay that supports efficient,bona fide EAD transcriptional activity and hence provides a new vehicle for molecular dissection of the EAD.

关键词： EwS/ATF1 Ew.ng's sarcoma microinjection Xenopus oocytes transcription EwS-activation domain

Effects of Risk Perception on Disaster Preparedness Toward Typhoons:An Application of the Extended Theory of Planned Behavior

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International Journal of Disaster Risk Science 2022年第1期13卷 100-113页

作者： Sai Leung ng Graduate Institute of Earth Science Chinese Culture UniversityTaipei 11114TaiwanChina

This study adopted an extended theory of planned behavior to understand how risk perception affected disaster preparedness *** intercept survey(n=286)was conducted at a typhoon-prone district of Hong Kong,China in 2019,then the data were analyzed using structural equation *** results indicated that risk perception and intention of preparedness were predictors of disaster preparedness *** perception significantly affected intention of preparedness and the effect was partially mediated by subjective *** perception also significantly affected attitude and perceived behavioral control,but attitude and perceived behavioral control were not significantly correlated with intention of *** only may this study supplement the existing literature of disaster preparedness toward typhoons,but also it provides insights for the planning and management of natural hazards and disaster risk reduction in Hong Kong,China.

关键词： Disaster preparedness behaviour Hong Kong,China Risk perception Structural equation modelling Theory of planned behaviour Typhoon preparedness

(E)-1-[4-(2-hydroxy-5-methoxybenzylideneamino)-phenyl]ethanone and (E)-1-[4-(2-hydroxy-4-methoxybenzylideneamino) phenyl]ethanone:X-ray and DFT-calculated structures

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Chinese Journal of Structural Chemistry 2011年第1期30卷 111-119页

作者： SAHn Onur BYKGngR Orhan ALBAYRAK igdem ODABASOGLU Mustafa Department of Physics Faculty of Arts and SciencesOndokuz Mayls University Department of Science Education Sinop University Chemistry Programme Pamukkale University 20159 Denizli

The isomeric structures of（E）-1-[4-（2-hydroxy-5-methoxybenzylideneamino）-phenyl] ethanone（I） and（E）-1-[4-（2-hydroxy-4-methoxybenzylideneamino） phenyl]ethanone（Ⅱ） ,both C16H15nO3,have been determined using X-ray diffraction techniques and characterized by IR,and their molecular structures have also been optimized at the B3LYP/6-31G（d,p） level using density functional theory（DFT） . The energetic behaviors of the title compounds in solvent media have been examined using B3LYP method with the 6-31G（d,p） basis set by applying the polarizable continuum model（PCM） . The total energies of the title compounds decrease with the increasing polarity of the solvent. In addition,DFT calculations of the title compounds＇ molecular electrostatic potentials（MEP） were performed at the B3LYP/6-31G（d,p） level of theory. X-ray study shows that the title compounds both have strong intramolecular O-H…n hydrogen bonds. The molecules of Ⅰ are linked into a one-dimensional framework structure by C-H…π interactions,while in Ⅱ,intermolecular π···π interactions result in the formation of infinite chains running along the [010].

关键词： crystal structure Schiff base DFT molecular electrostatic potential

Phenotypic nutrient up-take differences in an alley cropping system in semi-arid Machakos, Kenya

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Journal of Environmental Sciences 2001年第2期13卷 164-169页

作者： D.n. Mungai C.L.Coulson C.J. Stigter J.K. ng’ang’a D.n.Mugendi Department of Geography University of NairobiNairdbiKenya Department of Botany University of NairobiNairobiKenya Department of Enviromnental Sciences Graduate School of Productian EcologyWageningen UniversityDuivendaal 26701 APThe Netherlands Department of Meteorology University of NairobiNairobiKenya Kenya Forestry Research Instiute(KEFRI NairobiKanya)

Alley cropping of Cassia siamea and maize was studied in semi arid Kenya for soil fertility improvement. Katumani composite maize was planted except in the short rains of 1988 (SR88) when a hybrid variety was sown. Therefore the grain yield per row increased differently in the alley cropped maize (CM). Sole maize (SM) and CM yields were higher in SR88 than in the long rains of 1988 (LR88) by 62% and 38%, while yields from the same treatments in LR89 were only 21% and 45% of those in SR88 These differences in relative maize yields are attributed to differences between the two maize varieties in competition under nutrient stress conditions.

关键词： alley cropping Cassia siamea maize nutrients maize yield semi arid condition soil moisture Kenya

Assessment of the kinetic–frictional model for dense granular flow

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Particuology 2008年第1期6卷 50-58页

作者： Boon Ho ng Mojtaba Ghadiri Institute of Particle Science&Engineering University of LeedsLeeds LS2 9JTUK

This paper aims to quantitatively assess the application of kinetic-frictional model to simulate the motion of dry granular materials in dense condition, in particular, the annular shearing in Couette configuration. The weight of frictional stress was varied to study the contribution of the frictional stress in dense granular flows. The results show that the pure kinetic-theory-based computational fluid dynamics （CFD） model （without frictional stress） over-predicts the dominant solids motion of dense granular flow while adding frictional stress [Schaeffer, D. G. （1987）. Instability in the evolution equations describing incompressible granular flow. Journal of Differential Equations, 66（1）, 19-50] with the solids pressure of [Lun, C. nTK., Savage, S. B., Jeffrey, D. J., ＆ Chepurniy, n. （1984）. Kinetic theories for granular flow： Inelastic particles in Couette flow and slightly inelastic particles in a general flow field. Journal of Fluid Mechanics, 140, 223-256] in the CFD model improves the simulation to better conform available experimental results. The results also suggest that frictional stress transmission plays an important role in dense granular flow and should not be neglected in granular flow simulations. Compatible simulation results to the experimental data are seen by increasing the weight of frictional stress to a factor of 1.25-1.5. These improved simulation results suggest the current constitutive relations （kinetic-frictional model） need to be improved in order to better reflect the real dense granular flow.

关键词： Gas-solids flow CFD Constitutive relations Couette flow Kinetic theory Kinetic-frictional model

‘whole-molecule Disorder’ Refinement of 4-Tricyanovinyl-n,n-diethylaniline

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Chinese Journal of Structural Chemistry 2011年第9期30卷 1286-1288页

作者： ng Seik w.ng Department of Chemistry University of Malaya Chemistry Department Faculty of Science King Abdulaziz University

The molecule of 4-tricyanovinyl-n,n-diethylaniline is disordered about an axis that is close to the axis passing through the 1,4-carbon atoms. The disorder is a 1：1 type of disorder that involves only part of the molecule as the diethylamino substitutent and the three nitrogen atoms of the tricyanovinyl substituent are ordered. The treatment of the nearly ‘whole-molecule disorder’ by employing a small number of restraints is described. Crystal data： C15H14n4, triclinic, P , a = 7.1996（5）, b = 7.7232（5）, c = 12.4171（8） , α = 99.350（1）, β = 94.647（1）, γ = 103.312（1）o and V = 657.90（8） 3 at –173 K.

关键词： whole-molecule disorder

On compact splitting complex submanifolds of quotients of bounded symmetric domains

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Science China Mathematics 2017年第6期60卷 1057-1076页

作者： MOK ngaiming ng SuiChung Department of Mathematics The University of Hong Kong Department of Mathematics Shanghai Key Laboratory of PMMPEast China Normal University

we study compact complex submanifolds S of quotient manifolds X =Ω/F of irreducible bounded symmetric domains by torsion free discrete lattices of automorphisms, and we are interested in the characterization of the totally geodesic submanifolds among compact splitting complex submanifolds S C X, i.e., under the assumption that the tangent sequence over S splits holomorphically. we prove results of two types. The first type of results concerns S C X which are characteristic complex submanifolds, i.e., embedding Ω as an open subset of its compact dual manifold M by means of the Borel embedding, the non-zero （1, 0）-vectors tangent to S lift under a local inverse of the universal covering map π → X to minimal rational tangents of M. we prove that a compact characteristic complex submanifold S C X is necessarily totally geodesic whenever S is a splitting complex submanifold. Our proof generalizes the case of the characterization of totally geodesic complex submanifolds of quotients of the complex unit ball B^n obtained by Mok （2005）. The proof given here is however new and it is based on a monotonic property of curvatures of Hermitian holomorphic vector subbundles of Hermitian holomorphic vector bundles and on exploiting the splitting of the tangent sequence to identify the holomorphic tangent bundle Ts as a quotient bundle rather than as a subbundle of the restriction of the holomorphic tangent bundle Tx to S. The second type of results concerns characterization of total geodesic submanifolds among compact splitting complex submanifolds S C X deduced from the results of Aubin （1978） and Yau （1978） which imply the existence of Kahler-Einstein metrics on S C X. we prove that compact s- plitting complex submanifolds S C X of sufticiently large dimension （depending on ） are necessarily totally geodesic. The proof relies on the Hermitian-Einstein property of holomorphic vector bundles associated to TS, which implies that endomorphisms of such bundles are parallel, and the co

关键词： bounded symmetric domains tangent sequence splitting complex submanifolds varieties of minimal rational tangents K/ihler-Einstein metrics

Synthesis,Crystal Structure and Conformational Analysis of (E)-5-Methoxy-2-((4-methoxyphenylimino)methyl)phenol

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Chinese Journal of Structural Chemistry 2010年第3期29卷 359-364页

作者： ■AHn Onura BYKGngR Orhana ALBAYRAK i■demb ODABA■O■LU Mustafac Department of Physics Faculty of Arts and SciencesOndokuz Mayis University Department of Science Education Sinop University Chemistry Programme Pamukkale University

The title compound,（E）-5-methoxy-2-（（4-methoxyphenylimino）methyl）phenol（C15H15nO3）,crystallizes in monoclinic,space group P21/c with a=9.4361（6）,b=10.6212（5）,c=12.9338（9）,β=93.064（5）o,V=1294.41（14）3,Z=4,Dc=1.320 g/cm3,F（000）=544,Rint=0.116,T=296 K,μ=0.09 mm-1,the final R=0.051 and wR=0.148 for 1836 observed reflections with I2σ（I）.An extensive two-dimensional network of C–H…O hydrogen bonds and π-ring interactions are responsible for the crystal *** hydrogen bonds and C–H…π interactions produce R22（14）,R44（30） and R44（31） *** addition to the molecular geometry from X-ray experiment,the molecular geometry of the title compound in the ground state has been calculated using the semi-empirical（AM1 and PM3） and density functional theory method（DFT）（B3LYP） with 6-31G（d） basis *** determine the conformational flexibility,molecular energy profile of the title compound was obtained by semi-empirical（PM3 and AM1） and DFT/B3LYP calculations with respect to the selected degree of torsional freedom,which varied from –180° to ＋180° in a step of 10°.

关键词： crystal structure Schiff base PM3 AM1 DFT conformational analysis