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Different Versions of Perturbation Expansion Based on the Single-Trajectory Quadrature Method

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Communications in Theoretical Physics 2002年第3期38卷 271-280页

作者： ZHAO Wei-qin ju Chang-Sheng China Center of Advanced Science and Technology CCAST World Lab. P.O. Box 8730 Beijing 100080 China Institute of High Energy Physics the Chinese Academy of Sciences P.O. Box 9184 Beijing 100039 China Institute of High Energy Physics the Chinese Academy of Sciences P.O. Box 9184 Beijing 100039 China

The newly developed single trajectory quadrature method is applied to a two-dimensional example. Theresults based on different versions of new perturbation expansion and the new Green's function deduced from thismethod are compared with each other, also compared with the result from the traditional perturlbation theory. As thefirst application to higher-dimensional non-separable potential thc obtained result further confirms the applicability andpotential of this new method.

关键词： single trajectory quadrature, new perturbation expansion, Green function

Theoretical Study on the Intermolecular Interactions of Tetrazole Dimers

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Chinese Journal of Structural Chemistry 2005年第10期24卷 1203-1210页

作者： ZHOU Su-qin ju Xue-Hai XIAO He-Ming Department of Chemistry Nanjing University of Science and Technology Nanjing 210094 China

Tetrazole monomers （Ⅰ, Ⅱ） and all of their possible stable dimers （1, 2, 3, 4, 5, 6, 7 and 8） were fully optimized by DFT method at the B3LYP/6-311＋＋G^＊＊ level. Among the eight dimers, there were two 1H-tetrazole dimers, three 2H-tetrazole dimers and three hetero dimers of 1H-tetrazole and 2H-tetrazole. Vibrational frequencies were calculated to ascertain that each structure was stable （no imaginary frequencies）. The basis set superposition errors （BSSE） are 2.78, 2.28, 2.97, 2.75, 2.74, 2.18, 1.23 and 3.10 kJ/mol, and the zero point energy （ZPE） corrections for the interaction energies are 4.88, 4.18, 3.87, 3.65, 3.54, 3.22, 2.87 and 4.34 kJ/mol for 1, 2, 3, 4, 5, 6, 7 and 8, respectively. After BSSE and ZPE corrections, the greatest corrected intermolecular interaction energy of the dimers is -43.71 kJ/mol. The charge redistribution mainly occurs on the adjacent N-H…N atoms between submolecules. The charge transfer between two subsystems is very small. Natural bond orbital （NBO） analysis was performed to reveal the origin of the interaction. Based on the statistical thermodynamic method, the standard thermodynamic functions, heat capacities （C^0P）, entropies （S^0T） and thermal corrections to enthalpy （H^0T）, and the changes of thermodynamic properties from monomer to dimer in the temperature range of 200.00 K to 700 K have been obtained. 1H-tetrazole monomer can spontaneously turn into two stable dimers at 298.15 K.

关键词： tetrazole dimer intermolecular interaction DFT natural bond orbital,thermodynamic properties

Synthesis and Crystal Structure of a Two-dimensional Silver Framework Constructed by H_2idc (H_2idc = Iminodiacetic Acid)

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Chinese Journal of Structural Chemistry 2005年第6期24卷 711-715页

作者： LINXiu-E CAORong WANGYan-qin LIXiao-ju BIWen-Hua YUANDa-Qiang StateKeyLaboratoryofStructuralChemistry FujianInstituteofResearchontheStructureofMatterTheChineseAcademyofSciencesFuzhouFujian350002China

A new compound formulated [Ag2(idc)](NO3)?H2O (H2idc = iminodiacetic acid) was synthesized under mild conditions and characterized by IR spectrum and single-crystal X-ray diffraction. The crystal crystallizes in the monoclinic system, space group of P21/n with a = 5.5029(2), b = 11.1316(5), c = 15.5319 (1) ?, β = 96.038(3)o, V = 946.15(6) ?3, Z = 4, R = 0.0619 and wR = 0.1606. Its structure is a 2D polymer, whose repeat units consist of dinuclear silver cluster coordinated by two bridging iminodiacetic acids. In the complex, the Ag(I) ions adopt three coordinate fashions, and the Ag-Ag metal-metal contacts of 2.8418 ? are observed.

关键词： silver iminodiacetic acid crystal structure metal-metal interaction

Pretreatment of Cylindrical Coconut Activated Carbon and Performance as Catalyst Support

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Chemical Research in Chinese Universities 2013年第5期29卷 941-946页

作者： PAN Chong-gen YE Lin-qin WANG ju-hua BAO Li-xia QUE Yong-sheng National Center for International Research Zhejiang University Hangzhou 310058 P. R. China

Cylindrical coconut activated carbon（CCAC） support was graphitized at a high temperature（1900 ℃） in argon, then oxidized with an O2-N2-H2O mixture, and treated with nitric acid. Pretreatment of carbon support on its mechanical strength, physical structure, chemical composition and surface properties of cylindrical CCAC support was investigated by X-ray diffraction（XRD）, surface area analysis, scanning electron microscopy（SEM）, energy dis- persive spectroscopy（EDS）, thermogravimetric-differential thermogravimetric（TG-DTG） analysis and temperature programmed desorption-mass spectrometry（TPD-MS）, and the effect of CCAC support on the catalytic activities was also studied. The results show that the degree of graphitization, the purity（phosphorus, sulphur）, pore struc- ture（micropore, mesopore） and oxygen-containing functional groups（--COOH, --OH, --COOR） of carbon supports are obviously different, which have a great influence on the performance of Ru-based catalysts. After a series of pre- treatments, the surface physical and chemical properties of the commercial CCAC are modified and improved, and the activity of as-prepared Ru/AC catalyst is increased significantly.

关键词： Cylindrical coconut activated carbon(CCAC) Thermal treatment Mesopore Catalyst

Evaluating Soil Moisture Predictions Based on Ensemble Kalman Filter and SiB2 Model

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Journal of Meteorological Research 2019年第2期33卷 190-205页

作者： Xiaolei FU Zhongbo YU Ying TANG Yongjian DING Haishen LYU Baoqing ZHANG Xiaolei JIANG qin ju State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of Sciences College of Civil Engineering Fuzhou University State Key Laboratory of Hydrology–Water Resources and Hydraulic Engineering Hohai University Department of Geography Michigan State University College of Earth and Environmental Sciences Lanzhou University

Soil moisture is an important variable in the fields of hydrology, meteorology, and agriculture, and has been used for numerous applications and forecasts. Accurate soil moisture predictions on both a large scale and local scale for different soil depths are needed. In this study, a soil moisture assimilation and prediction based on the Ensemble Kalman Filter(EnKF) and Simple Biosphere Model(SiB2) have been performed in Meilin watershed, eastern China, to evaluate the initial state values with different assimilation frequencies and precipitation influences on soil moisture predictions. The assimilated results at the end of the assimilation period with different assimilation frequencies were set to be the initial values for the prediction period. The measured precipitation, randomly generated precipitation,and zero precipitation were used to force the land surface model in the prediction period. Ten cases were considered based on the initial value and precipitation. The results indicate that, for the summer prediction period with the deeper water table depth, the assimilation results with different assimilation frequencies influence soil moisture predictions significantly. The higher assimilation frequency gives better soil moisture predictions for a long lead-time. The soil moisture predictions are affected by precipitation within the prediction period. For a short lead-time, the soil moisture predictions are better for the case with precipitation, but for a long lead-time, they are better without precipitation. For the winter prediction period with a lower water table depth, there are better soil moisture predictions for the whole prediction period. Unlike the summer prediction period, the soil moisture predictions of winter prediction period are not significantly influenced by precipitation. Overall, it is shown that soil moisture assimilations improve its predictions.

关键词： soil moisture Ensemble Kalman Filter (EnKF) Simple Biosphere Model (SiB2) prediction

Preparation and characterization of the magnetic layered double hydroxide fluorescence composite

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Preparation and characterization of the magnetic layered dou...

Curcumin attenuates iron-overloaded stress to macrophages via up-regulation of SOD and Nrf2

第八届中国功能材料及其应用学术会议

作者： CAO ju-qin DONG Li-e ZHANG Feng-yuan GOU Guo-jing Medical chemistry department School of Basic MedicalNingxia medical university

ISBN: (纸本)9783037859698

A fluorescence composite of magnetic layered double hydroxide(MLDH) and fluorescein(FLU)was synthesizedby ion change *** crystal structure and properties of the intercalated compoundMLDH-FLU were investigated through XRD,IR,TEM and TG-DSC *** show that fluorescein is suited for intercalation assembly with MLDH,producing MLDH-FLU composite which could be used as afluorescence probe to test the celltransmission efficiency of MLDH delivery system.

关键词： Magnetic layered double hydroxides Intercalation Supra-molecular assembly Fluorescence probe

来源： cnki会议评论

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Traditional Medicine Research 2023年第8期8卷 68-75页

作者： Lin-Chao Zhu Pan-Li Tan ju-qin Sun Yi-Min Yao Medical Laboratory The First Affiliated Hospital of Zhejiang Chinese Medical University(Zhejiang Provincial Hospital of Chinese Medicine)Hangzhou 310006China

Background:It is known to all that iron overload is a fatal adverse effect on cells and ***,our study aimed to investigate the effects of curcumin on iron-overloaded stress in ***:Ferric ammonium citrate was added to the macrophage cell line(RAW264.7)to establish an iron-overloaded macrophage *** counting kit 8 assay was used to detect cell *** dismutase,reactive oxygen species,malondialdehyde,and apoptosis were performed to analyze the severity of cellular oxidative *** addition,quantitative real-time polymerase chain reaction and western blot were used to detect the expression of nuclear factor erythroid 2-related factor ***:The result showed that iron overload of macrophage was visualized by incubating in 40μM ferric ammonium citrate for 24 *** curcumin significantly reversed the iron overload-induced apoptotic cells at low(10μM)and middle(20μM)***,the levels of malondialdehyde and reactive oxygen species activity in the groups of curcumin at low(10μM)and middle(20μM)concentrations were significantly decreased,while superoxide dismutase activity was obviously increased compared with that of the ferric ammonium citrate group ***,we found that low(10μM)and middle(20μM)dose curcumin up-regulated nuclear factor erythroid 2-related factor 2 expression at mRNA and protein levels compared with the ferric ammonium citrate group ***:Curcumin reduces iron-overloaded stress in macrophages by activating nuclear factor erythroid 2-related factor 2 and enhancing the superoxide dismutase activity,thereby protecting cell apoptosis.

关键词： iron overload curcumin superoxide dismutase Nrf2 macrophage

Analysis of influence of observation operator on sequential data assimilation through soil temperature simulation with common land model

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Water Science and Engineering 2018年第3期11卷 196-204页

作者： Xiao-lei Fu Zhong-bo Yu Yong-jian Ding Ying Tang Hai-shen Lü Xiao-lei Jiang qin ju College of Civil Engineering Fuzhou UniversityFuzhou 350116China State Key Laboratory of Hydrology-Water Resources and Hydraulic Engineering Hohai UniversityNanjing 210098China State Key Laboratory of Cryospheric Science Northwest Institute of Eco-Environment and ResourcesChinese Academy of SciencesLanzhou 730000China Department of Geography Environmentand Spatial SciencesMichigan State UniversityEast LansingMI 48824USA

An observation operator is a bridge linking the system state vector and observations in a data assimilation system. Despite its importance, the degree to which an observation operator influences the performance of data assimilation methods is still poorly understood. This study aimed to analyze the influences of linear and nonlinear observation operators on the sequential data assimilation through soil temperature simulation using the unscented particle filter(UPF) and the common land model. The linear observation operator between unprocessed simulations and observations was first established. To improve the correlation between simulations and observations, both were processed based on a series of equations. This processing essentially resulted in a nonlinear observation operator. The linear and nonlinear observation operators were then used along with the UPF in three assimilation experiments: an hourly in situ soil surface temperature assimilation, a daily in situ soil surface temperature assimilation, and a moderate resolution imaging spectroradiometer(MODIS) land surface temperature(LST) assimilation. The results show that the filter improved the soil temperature simulation significantly with the linear and nonlinear observation operators. The nonlinear observation operator improved the UPF's performance more significantly for the hourly and daily in situ observation assimilations than the linear observation operator did, while the situation was opposite for the MODIS LST assimilation. Because of the high assimilation frequency and data quality, the simulation accuracy was significantly improved in all soil layers for hourly in situ soil surface temperature assimilation, while the significant improvements of the simulation accuracy were limited to the lower soil layers for the assimilation experiments with low assimilation frequency or low data quality.

关键词： Observation operator Unscented particle filter(UPF) Soil temperature MODIS LST Data assimilation

The Influence of SelW on GSH and GPx after Post-Transcriptional Gene Silencing in Mouse Skeletal Muscle Cells

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畜牧兽医学报 2009年第S1期40卷 62-66页

作者： WANG Xiao-long XU Kai qin Ou-ju CHEN Xiao-feng YANG Chuan-ping Wildlife Medicine Dept. Wildlife Resource CollegeNortheast Forestry University Key Laboratory of Forest Tree Genetic Improvement and Biotechnology of Ministry of Education Northeast Forestry University

The expression of Selenoprotein W(SelW)in C2C12 skeletal muscle cells was specifically decreased to examine its influence on the amount of glutathione(GSH)and the activity of glutathione peroxidase(GPx).SelW knock-down was performed by RNA interference(RNAi)in cultured muscle cells and verified by Real-time PCR and Western *** addition,cell viability,GSH content and GPx activity were *** results showed that the mRNA level and protein expression of SelW were decreased successfully by 71.9%and 68.8%relative to control values,cell viability decreased by 21.5%,GSH increased by 29.76%,and GPx increased by 47.58%.WST assay showed that compared with blank control,the value of positive group dropped 21.5%;In GSH and GPx assay,compared with blank control the positive group increased29.76%and 47.58%*** conclusion,SelW knock-down by RNAi caused significant cytotoxity in skeletal muscle cells and led to compensatory increases in GSH content and GPx *** findings are consistent with the suggestions from bioinformatics indicating an antioxidative role for SelW in skeletal muscle cells.

关键词： SelW GSH GPx anti-oxidation skeletal muscle cell