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Meet Our New Editorial Board Members of Rising Stars

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Chinese Journal of chemistry 2024年第16期42卷 1797-1805页

作者： Editorial Office of Chinese Journal of chemistry 不详

Editorial Board Memberof Rising Stars:Xiulin Fan,Professor,school of Materials Science and engineering Zhejiang university,Hangzhou,***:2003.2007,*** university,china.2007-2012,*** university,china(Supervisor:*** Chen).

关键词： china. Editorial Hangzhou

Differences between laminar convections through parallel plain planes with uniform wall temperature and heat flux in terms of process parameter

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Science china(Technological Sciences) 2010年第3期53卷 789-799页

作者： WANG LiangBi,LIN ZhiMin,WU Xiang&SONG KeWei school of Mechatronic engineering,lanzhou Jiaotong {3.,lanzhou 73.070,china 1. school of Mechatronic engineering Lanzhou Jiaotong University Lanzhou 730070 China

Using the process parameter description,we analyzed the difference between the characteristics of laminar convections through parallel plain planes with uniform temperature and heat *** results show the following.(1)On the wall surface of the developing region,under uniform heat flux boundary condition,the heat flux normal to the wall surface is transported through a convection process although the velocity is zero;the velocity gradient contributes to this transport,but under uniform temperature boundary condition,the heat flux normal to the wall surface is transported through a difussion process.(2)Inside the flow of the developing region,whether under uniform temperature or heat flux boundary condition,the heat flux along the main flow direction and the heat flux normal to the wall surface are transported through a convection process,and the contributions of velocity and velocity gradient are dependent on the thermal boundary condition.(3.On the wall surface of the fully developed region,under uniform heat flux boundary condition,the heat flux normal to the wall surface is transported through a convection process;the velocity gradient contributes to this transport,but under uniform temperature boundary condition,the heat flux normal to the wall surface is transported through a diffusion process.(4)Inside the flow of the fully developed region,under uniform temperature boundary condition,the heat flux along the main flow direction and the heat flux normal to the wall surface are transported through a convection process,and the velocity and velocity gradient contribute to these transports;under uniform heat flux boundary condition,the heat flux along the main flow direction and the heat flux normal to the wall surface are transported through a convection ***,the transport of the heat flux along the main flow direction is a no-net convection process;the velocity gradient contributes to the transport of the heat flux only in the normal direction o

关键词： mechanism of convective heat transfer description of process parameter parallel plain planes uniform wall temperature uniform wall heat flux laminar flow

Guided wave propagation in multilayered piezoelectric structures

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Science china(Physics,Mechanics & Astronomy) 2009年第7期52卷 1094-1104页

作者： GUO YongQiang1, CHEN WeiQiu2,3.& ZHANG YongLiang4 1 Key Laboratory of Mechanics on Disaster and Environment in Western china, Ministry of Education, and school of Civil engineering and Mechanics,{3., lanzhou 73.000, china 2 Key Laboratory of Soft Soils and Geoenvironmental engineering, Ministry of Education, and Department of Civil engineering, Zhejiang university, Hangzhou 3.0058, china 3.Department of engineering Mechanics, Zhejiang university, Hangzhou 3.0027, china 4 school of Civil engineering, lanzhou Jiaotong university, lanzhou 73.070, china Key Laboratory of Mechanics on Disaster and Environment in Western china Ministry of Education and School of Civil Engineering and Mechanics Lanzhou University Lanzhou 730000 China Key Laboratory of Soft Soils and Geoenvironmental engineering Ministry of Education and Department of Civil Engineering Zhejiang University Hangzhou 310058 China Department of engineering Mechanics Zhejiang University Hangzhou 310027 China school of Civil engineering Lanzhou Jiaotong University Lanzhou 730070 China

A general formulation of the method of the reverberation-ray matrix (MRRM) based on the state space formalism and plane wave expansion technique is presented for the analysis of guided waves in multilayered piezoelectric structures. Each layer of the structure is made of an arbitrarily anisotropic piezoelectric material. Since the state equation of each layer is derived from the three-dimensional theory of linear piezoelectricity, all wave modes are included in the formulation. Within the framework of the MRRM, the phase relation is properly established by excluding exponentially growing functions, while the scattering relation is also appropriately set up by avoiding matrix inversion operation. Consequently, the present MRRM is unconditionally numerically stable and free from computational limitations to the total number of layers, the thickness of individual layers, and the frequency range. Numerical examples are given to illustrate the good performance of the proposed formulation for the analysis of the dispersion characteristic of waves in layered piezoelectric structures.

关键词： multilayered piezoelectric structures the method of reverberation-ray matrix guided waves dispersion characteristic

Size effect of fullerene cages and encaged clusters in M3.@C2n

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Science china chemistry 2009年第5期52卷 584-589页

作者： GAN LiHua school of chemistry and Chemical engineering, Southwest {3., Chongqing 400715, china school of chemistry and Chemical engineering Southwest University Chongqing 400715 China

Based on the calculated findings that the sizes of encaged clusters determine the structures and the stability of C80-based trimetallic nitride fullerenes (TNFs), more extensive density functional theory calculations were performed on M3.@C68, M3.@C78 and M3.@C80 (M=Sc, Y and La). The calculated results demonstrated that the structures and stability undergo a transition with the increasing of the sizes of the cages and clusters. Sc3. is planar inside the three considered cages, Y3. is slightly pyramidal inside C68-6140 and C78-5 and planar inside I h C80-7, however, La3. is pyramidal inside all the three cages. Those cages with pyramidal clusters inside deformed considerably, compared with their parent cages. In these cases, the bonding of metallic atoms toward the cages does not play an impor-tant role, and the encaged cluster tends to be located inside the cages with the largest M-M and M-C distances so that the strain energy can be released mostly. These calculations revealed the size effect of fullerene cages and encaged clusters, and can explain the position priority of M3. inside fullerene cages and the differences in yield of M3.@C2n.

关键词： trimetallic nitride fullerenes (TNFs) density functional theory (DFT) size effect stability

Theoretical study of bifurcated bent blue-shifted hydrogen bonds CH_2…Y

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Science china chemistry 2008年第7期51卷 623-631页

作者： LI AnYong school of chemistry and Chemical engineering, Southwest {3., Chongqing 400715, china school of chemistry and Chemical engineering Southwest UniversityChongqing 400715China

Ab initio quantum chemistry methods were applied to study the bifurcated bent hydrogen bonds Y… H2CZ (Z = O, S, Se) and Y…H2CZ2 (Z = F, Cl, Br) (Y = Cl-, Br-) at the MP2/6-3.1++G(d,p) and MP2/6-3.1++G(2df,2p) levels. The results show that in each complex there are two equivalent blue-shifted H-bonds Y…H—C, and that the interaction energies and blue shifts are large, the energy of each Y…H—C H-bond is 15-27 kJ/mol, and Δr(CH) = -0.1 - -0.5 pm and Δv(CH) = 3. - 80 cm-1. The natural bond orbital analysis shows that these blue-shifted H-bonds are caused by three factors: large rehybridization; small direct intermolecular hyperconjugation and larger indirect intermolecular hy- perconjugation; large decrease of intramolecular hyperconjugation. The topological analysis of elec- tron density shows that in each complex there are three intermolecular critical points: there is one bond critical point between the acceptor atom Y and each hydrogen, and there is a ring critical point inside the tetragon YHCH, so these interactions are exactly H-bonding.

关键词： bifurcated bent H-bonds blue-shifted H-bonds topological property of electron density intramolecular hyperconjugation

Responding Depth of Photocatalytic Activity of TiO_2 Self-assembled Films

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Journal of Materials Science & Technology 2004年第4期20卷 472-474页

作者： Weichang HAO, Feng PAN, Tianmin WANG and Shukai ZHENG)Center of Materials Physics and chemistry, school of Science, Beijing university of Aeronautics and Astronautics, Beijing 100083.{3.Department of Materials Science, lanzhou university, lanzhou 73.000,{3. Ctr. of Mat. Phys. and Chem. Sch. of Sci. Beijing Univ. of Aero. and Astron. Beijing 100083 China Dept. of Mat. Sci. Lanzhou Univ. Lanzhou 730000 China

The electrostatically self-assembly method is getting strategically important to prepare multilayer thin films. With careful choice of component materials, this method should allow for the preparation of multilayer thin films with a variety of excellent technological properties. Ti02/PSS multilayer thin films with ordered structure were prepared by electrostatic self-assembly method. UV-Vis-NIR spectrophotometer, X-ray photoelectron spectroscopy (XPS), and atom force microscopy (AFM) were used to characterize the structure and performance of the multilayer films. Because electrostatically self-assembly method allows molecular-level control over the film composition and thickness, this paper studied the responding depth of photocatalytic activity of Ti02 self-assembled films in detail.

关键词： Responding depth Titanium dioxide Photocatalytic activity Electrostatically self-assembly

Structures and stability of isomers of[C,N,N,P]system

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Science china chemistry 2005年第5期48卷 415-423页

作者： KAN Wei1,2, ZHONG Hua1, YU Haitao1, FU Honggang1,3.& SUN Jiazhong1,3.1. school of chemistry and Materials Science, Heilongjiang university, Harbin 150080,{3. 2. school of chemistry and Chemical engineering, Qiqihar university, Qiqihar 161006,{3. 3. State Key Laboratory of Theoretical and Computational chemistry, Institute of Theoretical chemistry, Jilin university, Changchun 13.023.{3. 1. school of chemistry and Materials Science Heilongjiang University 150080 Harbin China 2. school of chemistry and Chemical engineering Qiqihar University 161006 Qiqihar China 3. Jilin university State Key Laboratory of Theoretical and Computational Chemistry Institute of Theoretical Chemistry 130023 Changchun China

Nine isomers, twenty transition states, and some relative dissociation fragments of [C,N,N,P] system were located at the B3.YP/6-3.1G(d) and QCISD(t)/6-3.1+G(2df) (single-point) levels of theory, and the isomerization, structures, and stability of these obtained isomers were suggested. The results indicate that four nonlinear chainlike isomers NCNP, NCPN, CNPN, and CNNP with 2A′ electronic state are kinetically stable. Other isomers are kinetically unstable to-wards isomerization or dissociation because of the corresponding smaller reaction barriers. Furthermore, calculated vibrational frequencies, rotational constants, dipole moments, the first adiabatic ionization energies, and adiabatic electron affinities of the four isomers may provide some theoretical information that is helpful for identifying their existence in future laboratory and interstellar investigations. The results are also compared with [Si,N,N,P] system.

关键词： potential energy surface, [C,N,N,P] system, isomerization, kinetic stability.

Boron rings containing planar octa- and enneacoordinate cobalt, iron and nickel metal elements

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Science china chemistry 2008年第7期51卷 607-613页

作者： LUO Qiong school of chemistry and Chemical engineering, Central South {3., Changsha 410083. china school of chemistry and Chemical engineering Central South UniversityChangsha 410083China

For a series of boron rings with planar hyper-coordinate 8th group transition metal atoms, singlet 1FeB8-2, multiplet kFeB9n (n = -1, k = 1; n = 0, k = 2), singlet 1CoB8n(n = -1, +1, +3., multiplet kCoB9n (n = +1, k = 2; n = 0, k = 1) and singlet 1NiB9+, the geometry structures have been optimized to be local minima on corresponding potential hyper-surfaces. The electron structures are discussed by orbital analysis and the aromaticity is predicted by nucleus-independent chemical shifts calculation at both the B3.YP/6-3.1+G* and BP86/6-3.1+G* levels of theory, respectively. The results suggest that all these structures with high symmetry planar geometries are stable and have aromatic properties with six π valence electrons.

关键词： planar hyper-coordinate transition metal DFT

Impacts of permafrost changes on alpine ecosystem in Qinghai-Tibet Plateau

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Science china Earth Sciences 2006年第11期49卷 1156-1169页

作者： WANG Genxu1,3., LI Yuanshou2 , WU Qingbai2 & WANG Yibo3.1. Institute of Mountain Hazards and Environment, Chinese Academy of Sciences, Chengdu 610041, china 2. Cold and Arid Regions Environmental and engineering Research Institute, Chinese Academy of Sciences, lanzhou 73.000, china 3. Resource and Environment school, lanzhou university, lanzhou 73.000, china 1. Institute of Mountain Hazards and Environment Chinese Academy of Sciences Chengdu 610041 China 3. Resource and Environment school Lanzhou University Lanzhou 730000 China 2. Cold and Arid Regions Environmental and engineering Research Institute Chinese Academy of Sciences Lanzhou 730000 China

Alpine cold ecosystem with permafrost environment is quite sensitive to climatic changes and the changes in permafrost can significantly affect the alpine ecosystem. The vegetation coverage, grassland biomass and soil nutrient and texture are selected to indicate the regime of alpine cold ecosystems in the Qinghai-Tibet Plateau. The interactions between alpine ecosystem and permafrost were investigated with the depth of active layer, permafrost thickness and mean annual ground temperature (MAGTs). Based on the statistics model of GPTR for MAGTs and annual air temperatures, an analysis method was developed to analyze the impacts of permafrost changes on the alpine ecosystems. Under the climate change and human engineering activities, the permafrost change and its impacts on alpine ecosystems in the permafrost region between the Kunlun Mountains and the Tanggula Range of Qinghai-Tibet Plateau are studied in this paper. The results showed that the per- mafrost changes have a different influence on different alpine ecosystems. With the increase in the thickness of active layer, the vegetation cover and biomass of the alpine cold meadow exhibit a significant conic reduction, the soil organic matter content of the alpine cold meadow ecosystem shows an exponential decrease, and the surface soil materials become coarse and gravelly. The alpine cold steppe ecosystem, however, seems to have a relatively weak relation to the permafrost environment. Those relationships resulted in the fact that the distribution area of alpine cold meadow decreased by 7.98% and alpine cold swamp decreased by 28.11% under the permafrost environment degradation during recent 15 years. In the future 50 years the alpine cold meadow ecosystems in different geomorphologic units may have different responses to the changes of the permafrost under different climate warming conditions, among them the alpine cold meadow and swamp ecosystem located in the low mountain and plateau area will have a relatively

关键词： permafrost environment, alpine cold ecosystem, statistics relationship, climate change, impacts, Qinghai-Tibet Plateau.