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The Affine Complete Hypersurfaces of Constant Gauss-Kronecker Curvature

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Acta Mathematica Sinica,English Series 2009年第8期25卷 1353-1362页

作者： bao Fu wang Department of Mathematics Sichuan University Chengdu 610064 P. R. China

Given a bounded convex domain Ω with C∞ boundary and a function ψ∈C∞（δΩ）, Li-Simon-Chen can construct an Euclidean complete and W-complete convex hypersurface M with constant affine Gauss-Kronecker curvature,... 详细信息

关键词： Gauss-Kronecker curvature affine completeness

CONVERGENCE OF THE WEIGHTED NONLOCAL LAPLACIAN ON RANDOM POINT CLOUD

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Journal of Computational Mathematics 2021年第6期39卷 865-879页

作者： Zuoqiang Shi bao wang Department of Mathematical Sciences Tsinghua UniversityBeijing 100084China Department of Mathematics University of UtahSalt Lake CityUT 84112USA

We analyze the convergence of the weighted nonlocal Laplacian(WNLL)on the high dimensional randomly distributed point *** analysis reveals the importance of the scaling weight,µ∼|P|/|S|with|P|and|S|being the number of entire and labeled data,respectively,in *** established result gives a theoretical foundation of the WNLL for high dimensional data interpolation.

关键词： Weighted nonlocal Laplacian Laplace-Beltrami operator Point cloud Highdimensional interpolation

Systematics of β and γ Parameters of O(6)-Like Nuclei in the Interacting Boson Model

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Chinese Physics Letters 1997年第7期14卷 503-506页

作者： wang bao-lin Department of Physics Huaiyin Teacher’s CollegeHuaiyin 223001

By comparing quadrupole moments between the interacting boson model(IBM)and the collective model,a simple calculation for the triaxial deformation parameters β and γ in the O(6)-like nuclei is presented,based on the intrinsic frame in the *** systematics of the β and γ are *** realistic cases are calculated for the even-even Xe,Ba,and Ce isotopes,and the smooth dependences of the strength ratio sθ_(3)/and the effective charges e2 on the proton and neutron boson numbers Nπand Nv are discovered.

关键词： collective boson charges

A prediction of drag reduction by entrapped gases in hydrophobic transverse grooves

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Science China(Technological Sciences) 2013年第12期56卷 2973-2978页

作者： wang bao wang JiaDao CHEN DaRong State Key Laboratory of Tribology Tsinghua University

The drag reduction effect of super-hydrophobic surface induced by the entrapped gas is unstable due to the gradual disappearance of the trapped *** this paper,a hydrophobic transverse grooved surface was designed to sustain gas in valleys.A detail numerical simulation was presented to investigate the flow field near the proposed *** water flowed over this surface,the entrapped gas was blocked by the ridges and the solid-liquid interface was replaced by the liquid-gas interface due to the entrapped gas,furthermore the micro-vortex formed in the *** there was an effective slippage between water and solid induced by the entrapped gas,the velocity gradient of boundary layer decreased,which contributed to a remarkable drag reduction ***,considering the extra undesired pressure drag reduction which negatively impacted the drag reduction effect of this method,the total drag coefficient including the viscous drag coefficient and the pressure coefficient was *** effective drag reduction rate of about 15%was achieved and the effect of this method was confirmed by experiments conducted in a high-speed water tunnel when grooves were optimized.

关键词： hydrophobic transverse groove gas skin-friction drag reduction computational fluid dynamics(CFD)

Underwater drag reduction by gas

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Friction 2014年第4期2卷 295-309页

作者： Jiadao wang bao wang Darong CHEN State Key Laboratory of Tribology Tsinghua UniversityBeijing 100084China

Publications on underwater drag reduction by gas have been gathered in the present *** methods,results and conclusions from the publications have been discussed and *** stable existence of gas is a requirement for underwater drag reduction induced by slippage at the water-solid interface.A superhydrophobic surface can entrap gas in surface structures at the water-solid ***,many experimental results have exhibited that the entrapped gas can disappear,and the drag gradually increases until the loss of drag reduction with immersion time and underwater *** some other surface structures were also experimented to hold the entrapped gas,from the analysis of thermodynamics and mechanics,it is difficult to prohibit the removal of entrapped gas in underwater surface ***,it is essential to replenish a new gas supply for continued presence of gas at the interface for continued underwater drag *** gas supplement is an effective method for underwater drag reduction,however,that needs some specific equipment and additional energy to generate gas,which limits its practical *** or supercavitation is a method for passive gas generation,but it is only adaptive to certain vehicles with high ***,even at low speed,the evaporation induced by liquid-gas-solid interface of a transverse microgrooved surface for continued gas supply has been discovered,which should be a promising method for practical application of underwater drag reduction by gas.

关键词： drag reduction entrapped gas skin friction underwater

Genomic insights into ruminant evolution: from past to future prospects

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Zoological Research 2019年第6期40卷 476-487页

作者： bao wang Lei Chen Wen wang State Key Laboratory of Genetic Resources and Evolution Kunming Institute of ZoologyChinese Academy of SciencesKunming Yunnan 650223China Kunming College of Life Science University of Chinese Academy of SciencesKunming Yunnan 650204China Center for Ecological and Environmental Sciences Northwestern Polytechnical UniversityXi'an Shaanxi 710072China Center for Excellence in Animal Evolution and Genetics Chinese Academy of SciencesKunming Yunnan 650223China

Ruminants(Ruminantia) are among the most successful herbivorous mammals, exhibiting wideranging morphological and ecological characteristics(such as headgear and multichambered stomach)and including various key livestock species(e. g.,cattle, buffalo, yak, sheep, and goat). Understanding their evolution is of great significance not only in scientific research but also in applications potential for human society. The rapid growth of genomic resources provides unprecedented opportunities to dissect the evolutionary histories and molecular mechanisms underlying the distinct characteristics of ruminants. Here we summarize our current understanding of the genetic, morphological, and ecological diversity of ruminants and provide prospects for future studies.

关键词： Rumin antia Genome evolution Phylogenomics Traits Adaptive evolution

Ca^(2+)-Calmodulin is Involved in Betacyanin Accumulation Induced by Dark in C_3 Halophyte Suaeda salsa

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Journal of Integrative Plant Biology 2007年第9期49卷 1378-1385页

作者： Chang-Quan wang bao-Shan wang College of Life Sciences Shandong Normal University Jinan 250014 China College of Life Sciences Shandong University of Technology Zibo 255049 China

The C3 halophyte Suaeda salsa was used to investigate the roles of Ca^2＋, Ca^2＋ channels, and calmodulin （CAM） in betacyanin metabolism. Seeds of S. salsa were cultured in both the dark and light for 3 days. The fresh weight and betacyanin content were much higher in S. salsa seedlings formed in the dark than in seedlings formed in the light. The addition of Ca^2＋ to the half-strength MS nutrient solution promoted betacyanin accumulation in the dark, whereas Ca^2＋ depletion by EGTA suppressed the dark-induced betacyanin accumulation in shoots of S. salsa. The Ca^2＋ channel blocker LaCl3 also inhibited dark-induced betacyanin accumulation. The highest activity of CaM and the maximum betacyanin content decreased by 51% and 45%, respectively, in shoots of S. salsa seedlings treated with the potent CaM antagonist chlorpromazine in the dark. Furthermore, the other CaM antagonist N-（6-aminohexyl）-5-chloro-l-naphthalenesulfonamide （W-7） also inhibited the activity of CaM and dark-dependent betacyanin accumulation, whereas its less active structural analog N-（6-aminohexyl）- 1-naphthalenesulfonamide （W-5） had little effect on the responses to dark of S. salsa seedlings. These results suggest that Ca^2＋, Ca^2＋-regulated ion channels, and CaM play an important role in dark-induced betacyanin accumulation in the shoots of the C3 halophyte S. salsa.

关键词： betacyanin Ca^2+ calmodulin darkness Suaeda salsa.

Equivalent Conditions of Local Asymptotics for the Solutions of Defective Renewal Equations, with Applications

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Acta Mathematicae Applicatae Sinica 2010年第3期26卷 503-512页

作者： Kai-yong wang Yue-bao wang Department of Mathematics Soochow University Suzhou 215006 China School of Mathematics and Physics Suzhou University of Science and Technology Suzhou 215009 China

The paper obtains some equivalent conditions of local asymptotics for the solutions of defective renewal equations in the heavy-tailed case. As applications, the paper gives a different proof of a classical result about the local distribution of the supremum of a random walk. These results are also applied in examples involving the renewal function for terminating renewal processes and the age-dependent branching processes.

关键词： Local asymptotics defective renewal equation heavy-tailed distribution random walk renewal

Theoretical Study on the Stable Structures and Aromaticities for Pnictogen Dianionic Sb4^2-, Bi4^2-, and （SbBi）2^2- Clusters

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Chinese Journal of Chemical Physics 2009年第1期22卷 75-81页

作者： Xing-bao wang Xian-xing Chi School of Physics and Electronic Information Wenzhou University Wenzhou 325027 China

Through the theoretical calculation of structural optimization, vibrational frequencies and atomization energies with one method of density functional theory （B3LYP） and two post- Hartree-Fock approaches （MP2, CCSD（T））, several stable isomers for new three pnictogen dianionic Sb4^2-, Bi4^2-, and （SbBi）2^2- species were determined. For two homoatomic Sb4^2- and Bi4^2- species, there are three stable isomers： square （D4h）, roof-shaped （C2v-1）, and C2v-2 structure with the square isomer being the ground state. For the heteroatomic dian- ionic （SbBi）2^2- species, there are also three stable isomers： rhombus （D2h）, roof-shaped （C1）, and C2v structures with the rhombic isomer being the ground state. The calculated NICS values show that nucleus-independent chemical shifts （NICS） values of roof-shaped isomers for Sb4^2-, Bi4^2-, and （SbBi）2^2- species are all negative, consequently indicating that these roof-shaped isomers possess aromaticities. NICS values for the planar ring isomers are all positive, suggesting that these three planar ring isomers have antiaromatic characters. The aromaticity for the two stable roof-shaped and square isomers are preliminarily explained and discussed with MO analysis.

关键词： Pnictogen cluster Ab initio Aromaticity Nucleus-independent chemical shift