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Science china(Technological Sciences) 2012年第8期55卷 2362-2376页

作者： YE JianHong JENG DongSheng chan A H c Division of civil Engineering University of DundeeDundee DD14HNUK Department of civil Engineering University of BirminghamBirminghamB152TTUK

In this study,based on the dynamic Biot＇s theory ＂u-p＂ approximation,a 3D finite element method（FEM） numerical soil model is developed,in which the Generalized Newmark-β method is adopted to determine the time *** developed 3D FEM soil model is a part of the coupled model PORO-WSSI 3D for 3D wave-seabed-marine structures interaction problem,and is validated by the analytical solution proposed by Wang（2000） for a laterally infinite seabed loaded by a uniform *** adopting the developed 3D soil model,the consolidation of seabed under a caisson breakwater and hydrostatic pressure is *** numerical results show that the caisson breakwater built on seabed has very significant effect on the stresses/displacements fields in the seabed foundation after the transient deformation and primary consolidation are *** parametric study indicates that the Young＇s modulus E of seabed is the most important parameter to affect the settlement of breakwater,and the displacement fields in seabed *** the consolidation status as the initial condition,the interaction between ocean wave,caisson breakwater and seabed foundation is briefly *** 3D ocean wave is determined by solving the Navier-Stokes equations with finite volume method（FVM）.The numerical results indicate that there is intensive interaction between oceean wave, caisson breakwater and seabed foundation; and the breakwater indeed can effectively block the wave energy propagating to the coastline.

关键词： consolidation wave-seabed-breakwater interaction unsaturated seabed breakwater Biot's theory Navier-Stokes equation

Asymmetric synthesis of tetrahydropyran[3,2-c]quinolinones via an organocatalyzed formal[3+3]annulation of quinolinones and MBH 2-naphthoates of nitroolefin

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chinese chemical Letters 2020年第3期31卷 697-700页

作者： Jian Li Qi-Long Hu Xue-Ping chen ke-Qiang Hou Albert S.c.chan Xiao-Feng Xiong Guangdong key Laboratory of chiral Molecule and Drug Discovery School of Pharmaceutical SciencesSun Yat-sen UniversityGuangzhou 510006China

An efficient asymmetric and enantio-swithchable organocatalytic[3+3]annulation reaction using MBH-2-naphthoates of nitroalkenes and 4-hydroxyquinolin-2(1H)-ones has been *** substituted tetrahydropyrano[3,2-c]qui noli nones scaffolds with two adjacent stereogenic centers are obtained with high yield(up to 95%yield)and good stereoselectivities(up to>20:1 dr and 96%ee)in an enantio-switchable ***,gram scale synthesis was achieved and the nitro group could easily transform into an amino group without any appreciable loss in the diastereo-and enantioselectivity.

关键词： Organocatalysis Asymmetric synthesis Enantioswitchable cinchona alkaloid Tetrahydropyran[3,2-c]quinolines

Porphyrins and Phthalocyanines catalyzed Direct c--H Arylation

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chinese Journal of chemistry 2016年第10期34卷 955-961页

作者： ching Tat To Wu Yang kin Shing chan Department of chemistry The Chinese University of Hong Kong Shatin New Territories Hong Kong China

catalytic direct functionalization of unreactive c--H bonds represents a sustainable and more atom economical transformation process. Porphyrin and pbthalocyanine derivatives show promising catalytic activities in direct c-- H arylation reactions. These reactions share a common c--c bond formation process via homolytic radical substi- tution. This review summarizes the catalytic direct c--H arylation reactions catalyzed by metalloporphyrins, free base porphyrins and free base phthalocyanines.

关键词： porphyrin phthalocyanine c--H arylation c--c coupling radical reaction

Recent Decrease in the Difference in Tropical cyclone Occurrence between the Atlantic and the Western North Pacific

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Advances in Atmospheric Sciences 2022年第9期39卷 1387-1397页

作者： Johnny c.L.chan kin Sik LIU Guy carpenter Asia-Pacific climate Impact centre School of Energy and EnvironmentCity University of Hong KongTat Chee Ave.KowloonHong KongChina

climatologically,among all ocean basins,the western North Pacific(WNP)has the largest annual number of tropical cyclones(Tcs)of around 26 while the Atlantic has around 13,yielding a difference of ***,the difference is-7 in 2020,with 30 Tcs in the Atlantic and 23 in the WNP,which is the most negative difference within the last 46 *** fact,during the last 26 years,the difference in Tc number is below 10 in ten years,with four years being *** a decreasing difference in Tc number can be attributed to the natural multidecadal variation of the Atlantic Multidecadal Oscillation and Interdecadal Pacific Oscillation,as well as other external forcings such as anthropogenic aerosol forcing and increased greenhouse gases,with the additional impact from the La Niña *** result has significant implications on climate model projections of future Tc activity in the two ocean basins.

关键词： tropical cyclone frequency Atlantic Multidecadal Oscillation Interdecadal Pacific Oscillation climate change

Growing Threat of Rapidly-Intensifying Tropical cyclones in East Asia

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Advances in Atmospheric Sciences 2022年第2期39卷 222-234页

作者： kin Sik LIU Johnny c.L.chan Guy carpenter Asia-Pacific climate Impact centre School of Energy and EnvironmentCity University of Hong KongTat Chee Ave.KowloonHong KongChina

This study examines the long-term change in the threat of landfalling tropical cyclones(Tcs) in East Asia over the period 1975–2020 with a focus on rapidly intensifying(RI) Tcs. The increase in the annual number of RI-Tcs over the western North Pacific and the northwestward shift of their genesis location lead to an increasing trend in the annual number of landfalling RI-Tcs along the coast of East Asia. The annual power dissipation index(PDI), a measure of the destructive potential of RI-Tcs at landfall, also shows a significant increasing trend due to increases in the annual frequency and mean landfall intensity of landfalling RI-Tcs. The increase in mean landfall intensity is related to a higher lifetime maximum intensity(LMI) and the LMI location of the landfalling RI-Tcs being closer to the coast. The increase in the annual PDI of East Asia is mainly associated with landfalling Tcs in the southern(the Philippines, South china, and Vietnam) and northern parts(Japan and the korean Peninsula) of East Asia due to long-term changes in vertical wind shear and Tc heat potential. The former leads to a northwestward shift of favorable environments for Tc genesis and intensification, resulting in the northwestward shift in the genesis, RI, and LMI locations of RI-Tcs. The latter provides more heat energy from the ocean for Tc intensification, increasing its chances to undergo RI.

关键词： tropical cyclone landfall tropical cyclone intensity climate change rapid intensification

Dynamically encircling an exceptional point in antiparity-time symmetric systems:asymmetric mode switching for symmetry-broken modes

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Light(Science & Applications) 2019年第1期8卷 376-384页

作者： Xu-Lin Zhang Tianshu Jiang c.T.chan State key Laboratory of Integrated Optoelectronics College of Electronic Science and EngineeringJilin UniversityChangchunChina Department of Physics The Hong Kong University of Science and TechnologyClear Water BayHong KongChina

Dynamically encircling an exceptional point(EP)in parity-time(PT)symmetric waveguide systems exhibits interesting chiral dynamics that can be applied to asymmetric mode switching for symmetric and anti-symmetric *** counterpart symmetry-broken modes(i.e.,each eigenmode is localized in one waveguide only),which are more useful for applications such as on-chip optical signal processing,exhibit only non-chiral dynamics and therefore cannot be used for asymmetric mode ***,we solve this problem by resorting to anti-parity-time(anti-PT)symmetric systems and utilizing their unique topological structure,which is very different from that of PT-symmetric *** find that the dynamical encircling of an EP in anti-PT-symmetric systems with the starting point in the PT-broken phase results in chiral *** a result,symmetry-broken modes can be used for asymmetric mode switching,which is a phenomenon and application unique to anti-PT-symmetric *** perform experiments to demonstrate the new wave-manipulation scheme,which may pave the way towards designing on-chip optical systems with novel functionalities.

关键词： symmetric asymmetric symmetry

Plasma Epstein-Barr virus DNA as a biomarker for nasopharyngeal carcinoma

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chinese Journal of cancer 2014年第12期33卷 598-603页

作者： k.c.Allen chan Li ka Shing Institute of Health Sciences The Chinese University of Hong Kong Department of chemical Pathology The Chinese University of Hong Kong Prince of Wales Hospital State key Laboratory in Oncology in South china Sir Y.K. Pao Centre for Cancer The Chinese University of Hong Kong Prince of Wales Hospital

Nasopharyngeal carcinoma(NPc)is common in southern china and Southeast ***-Barr virus(EBV)infection is an important etiology for NPc,and EBV genome can be detected in almost all tumor tissues of NPc in this *** EBV DNA,when quantitatively analyzed using real-time polymerase chain reaction(PcR),has been developed as a biomarker for *** this review,the different clinical applications of plasma EBV DNA in the management of NPc,including screening,monitoring,and prognostication,are *** addition,the biological issues of circulating EBV DNA,including the molecular nature and clearance kinetics,are also explored.

关键词：病毒DNA 生物标志物鼻咽癌等离子体聚合酶链反应东南亚地区 EBV 中国南部

Asymptotic analysis of dispersive tsunami from a slender fault

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Journal of Hydrodynamics 2019年第6期31卷 1073-1084页

作者： Yile Li chiang c.Mei I-chi chan katy TexasUSA Department of civil and Environmental Engineering Massachusetts Institute of TechnologyCambridgeMAUSA Department of civil Engineering National Taiwan UniversityTaipeiChina

An approximate theory is developed for the two-dimensional propagation of tsunami emanated from a slender fault of fine *** significant contrasts between the sea depth,fault width,fault length and the bathymetric length scales,we invoke parabolic approximation to deduce a linear kademtsev・Petviashivili(k-P)equation governing the two-dimensional propagation of dispersive long waves over great *** techniques are employed to explore the far-field radiation in the forward and spanwise directions in a sea of constant *** solution can be used as a convenient input for predicting local variations of wave scattering and possibly breaking along a coast.

关键词： Slender fault dispersion in transocean tsunami Linear kademtsev-Petviashivi1i approximation

Purge and trap method to determine alpha factors of VOc liquid-phase mass transfer coefficients

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chinese Science Bulletin 2000年第S1期45卷 76-79页

作者： S.c.Lee L.Y.chan c.Y.chan Department of civil & Structural Engineering The Hong Kong Polytechnic UniversityHong KongChina Correspondence should be addressed to Wang XinmingDepartment of Civil & Structural EngineeringThe Hong Kong Polytechnic UniversityHong KongChina Correspondence should be addressed to Wang XinmingDepartment of Civil & Structural EngineeringThe Hong Kong Polytechnic UniversityHong KongChina Correspondence should be addressed to Wang Xinming

A theoretical approach and laboratory practice of determining the alpha factors of volatile organic compound (VOc) liquid-phase mass transfer coefficients are present in this study. Using Purge & Trap concentrator, VOc spiked water samples are purged by high-purity nitrogen in the laboratory, the VOc liquid-phase mass transfer rate constants under the laboratory conditions are then obtained by observing the variation of VOcs purged out of the water with the purge time. The alpha factors of VOc liquid-phase mass transfer coefficients are calculated as the ratios of the liquid-phase mass transfer rate constants in real water samples to their counterparts in pure water under the same experimental conditions. This direct and fast approach is easy to control in the laboratory, and would benefit mutual comparison among researchers, so might be useful for the study of VOc mass transfer across the liquid-gas interface.

关键词： mass transfer coefficient purge and trap volatile organic compounds alpha factor.

current Transport in copper Schottky contacts to a−Plane/ c−Plane n-Type MoSe_(2)

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chinese Physics Letters 2011年第8期28卷 254-257页

作者： c.k.Sumesh k.D.Patel V.M.Pathak R.Srivastav Department of Physics Faculty of Technology and EngineeringCharotar University of Science and TechnologyCHANGA 388421GujaratIndia Department of Physics Sardar Patel UniversityVallabh Vidyanagar 388120GujatatIndia

We identically prepared cu-nMoSe_(2)(a−plane)and cu-nMoSe_(2)(c−plane)Schottky barrier diodes(SBDs)on the same n-type MoSe_(2) single *** effective Schottky barrier heights(SBHs)and ideality factors were obtained from the current−voltage-temperature(I–V–T)*** barrier height and ideality factor,estimated from the conventional thermionic emission model by assuming a Gaussian barrier distribution,are highly dependent on temperature.A notable deviation from the theoretical Richardson constant value is also observed in the conventional Richardson *** decrease in the experimental barrier heightΦB0 and an increase in the ideality factor n with a decrease in temperature have been explained on the basis of barrier height inhomogeneities at the metal−semiconductor *** is proven that the presence of a distribution of barrier heights is responsible for the apparent decrease of the zero bias barrier *** voltage dependence of the standard deviation causes the increase of the ideality factor at low *** value of the Richardson constant obtained without considering the inhomogeneous barrier heights is much closer than the theoretical *** cu-nMoSe_(2)(a−plane)Schottky diode shows better results in comparison with the nMoSe_(2)(c-plane)Schottky diode.

关键词： Schottky temperature ideality