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The α-Geometric Structures on Manifold of Positive Definite Hermite Matrices

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Acta Mathematica Sinica,English Series 2014年第12期30卷 2137-2145页

作者： Xiao min duan Hua Fei SUN Lin Yu PENG Department of Mathematics Beijing Institute of Technology School of Science Dalian Jiaotong University Department of Mathematics University of SurreyGuildfordSurrey GU2 7XHUK

Geometric structures of a manifold of positive definite Hermite matrices are considered from the viewpoint of information geometry.A Riemannian metric is defined and dual α-connections are *** the fact that the manifold is ±l-flat is ***,the divergence of two points on the manifold is given through dual potential ***,the optimal approximation of a point onto the submanifold is ***,some simulations are given to illustrate our results.

关键词： Positive definite Hermite matrices information geometry optimal approximation

Can Current AGCMs Reproduce Historical Changes in the Atmospheric Diabatic Heating over the Tibetan Plateau?

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Atmospheric and Oceanic Science Letters 2014年第2期7卷 143-148页

作者： duan an-min XIAO Zhi-Xiang HU Jun duan an-min XIAO Zhi-Xiang HU Jun State Key Laboratory of Numerical Modelling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmospheric Physics Chinese Academy of Sciences Beijing 100029 China University of Chinese Academy of Sciences Beijing 100049 China Key Laboratory of Meteorological Disaster Nanjing University of Information Science and Technology Ministry of Education Nanjing 210044 China

Recent studies have demonstrated a persistent decreasing trend in the spring sensible heat(SH) source over the Tibetan Plateau(TP) during the past three decades. By comparing simulations from nine state-of-the-art atmospheric general circulation models(AGCMs) driven by historical forcing fields with both observational data and five reanalysis datasets, the authors found that the AGCMs are unable to reproduce the change in the SH flux over the TP. This deficiency arises because the observed decreasing trend in SH flux depends primarily on the change in surface wind speed according to the bulk formula, whereas in the models it is also influenced largely by changes in the land-air temperature difference related to the systematic cold bias. In addition, an obvious discrepancy exists in other aspects of the diabatic heating simulated by the models, suggesting that a significant improvement is required in the physical schemes associated with land surface processes and diabatic heating over the complicated topography.

关键词： Tibetan Plateau AGCMs diabatic heating trend

Photoresponsive thin films containing an azobenzene derivative intercalated with a layered double hydroxide

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Chinese Science Bulletin 2010年第34期55卷 3894-3900页

作者： WANG XinRui LU Jun WEI min duan Xue State Key Laboratory of Chemical Resource Engineering Beijing University of Chemical Technology Beijing 100029 China

Two kinds of optically transparent thin films with photochromic properties have been fabricated based on co-intercalation of 4-(4-anilinophenylazo)benzenesulfonate(AO5)and sodium dodecylbenzene sulfonate(SDS)into the galleries of a ZnAl layered double hydroxide(LDH)by two synthetic methods:solvent evaporation and in situ *** two films possess LDH crystallites in different orientations relative to the substrates depending on their fabrication method:horizontal and *** relationship between the photochromic behavior of the interlayer chromophore and the orientation of the LDH crystallites is studied *** orientation of the LDH crystallite influences the photochromic behavior of the *** films exhibited different absorption and wettability characteristics,providing the potential for application of dye-LDH films as photochromic materials and light sensitive switches.

关键词：层状双金属氢氧化物偶氮苯衍生物光敏薄膜光致变色行为十二烷基苯磺酸钠晶粒取向光致变色材料 LDH

Exciton-Dependent Pre-formation Probability of Composite Particles

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Communications in Theoretical Physics 2007年第6期47卷 1106-1110页

作者： ZHANG Jing-Shang WANG Ji-min duan Jun-Feng China Institute of Atomic Energy P.O. Box 275（41） Beijing 102413 China

In Iwamoto-Harada model the whole phase space is full of fermions. When the momentum distributions of the exciton states are taken into account, the pre-formation probability of light composite particles could be improved, and the exciton state-dependent pre-formation probability has been proposed. The calculated results indicate that the consideration of the momentum distribution enhances the pre-formation probability of [1, m] configuration, and suppresses that of [ι 〉 1, m] configurations seriously.

关键词： pre-formation probability pre-equilibrium emission

A New Ocean Mixed-Layer Model Coupled into WRF

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Atmospheric and Oceanic Science Letters 2012年第3期5卷 170-175页

作者： WANG Zi-Qian duan an-min The State Key Laboratory of Numerical Modeling for Atmospheric Sciences and Geophysical Fluid Dynamics Institute of Atmos- pheric Physics Chinese Academy of Sciences Beijing 100029 China Graduate University of Chinese Academy of Sciences Beijing 100049 China

A new mesoscale air-sea coupled model (WRF- OMLM-Noh) was constructed based on the Weather Research and Forecasting (WRF) model and an improved Mellor-Yamada ocean mixed-layer model from Noh and Kim (OMLM-Noh). Through off-line tests and a simulation of a real typhoon, the authors compared the performance of the WRF-OMLM-Noh with another existing ocean mixed-layer coupled model (WRF-OMLM-Pollard). In the off-line tests with Tropical Ocean Global Atmosphere Program's Coupled Ocean Atmosphere Response Experiment (TOGA-COARE) observational data, the results show that OMLM-Noh is better able to simulate sea surface temperature (SST) variational trends than OMLM -Pollard. Moreover, OMLM-Noh can sufficiently reproduce the diurnal cycle of SST. Regarding the typhoon case study, SST cooling due to wind-driven ocean mixing is underestimated in WRF-OMLM-Pollard, which artificially increases the intensity of the typhoon due to more simulated air-sea heat fluxes. Compared to the WRF- OMLM-Pollard, the performance of WRF-OMLM-Noh is superior in terms of both the spatial distribution and temporal variation of SST and air-sea heat fluxes.

关键词： WRF-OMLM-Noh sea surface temperature ocean mixed layer air-sea coupled model

Functional response, host stage preference and interference of two whitefly parasitoids

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Insect Science 2016年第1期23卷 134-144页

作者： Hai-Yun Xu Nian-Wan Yang min duan Fang-Hao Wan State Key Laboratory for Biology of Plant Diseases and Insect Pests Institute of Plant Protection Chinese Academy of Agricultural Sciences Beijing Agricultural Genome Institute at Shenzhen Chinese Academy of Agricultural Sciences Shenzhen Qingdao Agricultural University Qingdao Shandong Province China

The functional responses of two parasitoids, Eretmocerus hayati Zolnerowich ＆ Rose and Encarsia sophia Girault ＆ Dodd, of whitefly Bemisia tabaci Gennadius Middle East-Asia minor 1 were studied under laboratory conditions. In addition, the influence of host density and host stage on the competitive interactions between the two parasitoids, and biological control effect on whitefly were evaluated. In the functional response study, adult parasitoids were tested individually, with a conspecific or heterospecific competitor. Both Er. hayati and En. sophia exhibited a type II response to increasing host density, whether a conspecific or heterospecific competitor was present or not. Difference of searching rates and handling times between treatments suggested interference interactions existed between two parasitoid species. In the host stage preference study, two parasitoid species were jointly tested. Er. hayati had a competitive advantage over En. sophia when provided young host instars （first and second instar）, whereas no advantage was found on old host instars （third and fourth instar）. The biological control effect ofEr hayati and En. sophia in different introductions varied with host density. However, the effect of host instar on host mortality was not significant. These findings provide information for the practice of biological control and give better insight into how parasitoid species may coexist in diverse environments.

关键词： Bemisia tabaci Encarsia sophia Eretmocerus hayati functional response interspecific competition

Uncertainties in Quantitatively Estimating the Atmospheric Heat Source over the Tibetan Plateau

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Atmospheric and Oceanic Science Letters 2014年第1期7卷 28-33页

作者： duan an-min WANG Mei-Rong XIAO Zhi-Xiang State Key Laboratory of Numerical Modeling for Atmospheric Science and Geophysical Fluid Dynamics Institute of Atmospheric PhysicsChinese Academy of Sciences Nanjing University of Information Science&Technology University of Chinese Academy of Sciences

As a huge,intense,and elevated atmospheric heat source(AHS) approaching the mid-troposphere in spring and summer,the Tibetan Plateau(TP) thermal forcing is perceived as an important factor contributing to the formation and variation of the Asian summer *** numerous studies devoted to determine the strength and change of the thermal forcing of the TP on the basis of various data sources and methods,uncertainties remain in quantitative estimation of the AHS and will persist for the following reasons:(1) Routine meteorological stations cover only limited regions and show remarkable spatial inhomogeneity with most distributed in the central and eastern ***,all of these stations are situated at an altitude below 5000 ***,the large area above that elevation is not included in the data.(2) Direct observations on heat fluxes do not exist at most stations,and the sensible heat flux(SHF) is calculated by the bulk formula,in which the drag coefficient for heat is often treated as an empirical constant without considering atmospheric stability and thermal roughness length.(3) Radiation flux derived by satellite remote sensing shows a large discrepancy in the algorithm in data inversion and complex terrain.(4) In reanalysis data,besides the rare observational records employed for data assimilation,model bias in physical processes induces visible errors in producing the diabatic heating fields.

关键词： Tibetan Plateau atmospheric heat source data bias uncertainties

Significantly reduced function of T cells in patients with acute arterial thrombosis

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Journal of Geriatric Cardiology 2015年第3期12卷 287-293页

作者： Wen-Wen YAN Kun-Shan ZHANG Qiang-Lin duan Le-min WANG i University School of Medicine ShanghaL China

Objectives To explore the intrinsic factors related to the pathogenesis of acute arterial thrombosis （AAT） and to elucidate the patho- genesis of AAT on the basis of differentially expressed genes. Methods Patients with acute myocardial infarction （AMI）, stable angina （SA） and healthy controls （n = 20 per group） were recruited, and the whole human genome microarray analysis was performed to detect the differentially expressed genes among these subjects. Results Patients with AMI had disease-specific gene expression pattern. Biological functional analysis showed the function of T cells was significantly reduced, the mitochondrial metabolism significantly decreased, the ion metabolism was abnormal, the cell apoptosis and inflammatory reaction increased, the phagocytosis elevated, the neutrophil-mediated immunity increased and the post-traumatic repair of cells and tissues increased in AMI patients. The biological function in SA group and healthy controis remained stable and was comparable. Conclusions The reduced function ofT cell gene models in AAT showed the dysfunction of the immune system. The pathogenesis of AAT may be related to the inflammatory reaction after arterial intima infection caused by potential pathogenic microorganisms.

关键词： Acute arterial thrombosis Gene expression pattern Myocardial infarction Stable angina

Simulation and prototype testing of multi-wire drift chamber arrays for the CEE

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Nuclear Science and Techniques 2020年第1期31卷 102-111页

作者： Li-ming Lyu Han Yi Li-min duan Zhao Zhang Zhi-Gang Xiao Department of Physics Tsinghua UniversityBeijing 100084China Institute of Modern Physics Chinese Academy of SciencesLanzhou 730000China

The building of a large-scale external-target experiment, abbreviated as CEE, in the cooling storage ring at the Heavy Ion Research Facility in Lanzhou has been planned. The CEE is a multi-purpose spectrometer that will be used for various studies on heavy-ion collisions. A multi-wire drift chamber(MWDC) array is the forward tracking detector of the CEE. In this work, GEANT4 simulations were performed for the MWDC forward tracking array with a focus on the track reconstruction algorithm. Combined with the time of flight information,particle identification is achieved. The residue is about 30 μm, while the tracking efficiency is higher than 90%with the current redundancy. In addition, a prototype of the forward tracking system using three MWDCs was assembled and tested using a high-energy proton beam. The firing efficiency of the detector and the reconstruction accuracy of the prototype were derived. The track residue for the protons at about 400 MeV/c is better than 300 μm, meeting the requirements of the CEE. Suggestions for improving the performance of the forward tracking system are given.

关键词： CEE Multi-wire drift chamber array Track finding and reconstruction