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Complete catalytic oxidation of o-xylene over CeO_2 nanocubes

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Journal of Environmental Sciences 2011年第1期23卷 160-165页

作者： lian he Yunbo Yu Changbin Zhang Hong he State Key. Laboratory of Environmental Chemistry and Ecotoxicology Research Center for Eco-Environmental Sciences Chinese Academy of Sciences Beijing 100085 China

The activities of CeO2 nanocubes calcined at different temperatures were tested for catalytic oxidation of o-xylene. Using CeO2 nanocubes as catalysts, complete catalytic oxidation of o-xylene was achieved below 210℃. The CeO2 nanomaterials were characterized by means of BET, X-ray diffraction （XRD）, transmission electron microscopy （TEM）, and high-resolution transmission electron microscopy （HRTEM）. From the TEM images, all CeO2 nanocubes displayed cubic morphology irrespective of calcination temperature. The HRTEM images revealed that these nanocubes were enclosed by reactive {001} planes, which may contribute to the intrinsically catalytic property of o-xylene oxidation. The higher activity of CeO2 nanocubes calcined at 550℃ than those calcined at above 550℃ was attributed to their smaller crystallite size and larger surface area. The influences of reaction conditions were also studied, which found that a higher reaction temperature was necessary for complete catalytic oxidation of o-xylene at higher weight hourly space velocity （WHSV） and o-xylene concentration.

关键词： CeO2 nanocubes o-xylene catalytic oxidation calcination temperature

Characterization and Crystal Structure of Bis(N'-ethyl-N-piperazinly-carbodithioato-S,S') Nickel(II) Complex:Ni(S_2CNC_4H_8NC_2H_5)_2

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Chinese Journal of Structural Chemistry 2006年第10期25卷 1260-1264页

作者： WANG Ying YAN lian-he School of Chemical Engineering Nanjing University of Science and Technology Nanjing Jiangsu 210094 China

The title compound has been prepared and characterized by elemental analysis, infrared and FT-Raman spectra, and thermal analysis. The crystal and molecular structures of bis（N＇-ethyl-N-piperazinly-carbodithioato-S,S＇） nickel（Ⅱ） complex （Ni（S2CNC4H8NC2H5）2） were determined by X-ray diffraction methods. The crystal crystallizes in the triclinic system, space group PI^- with a = 0.66770（15）, b = 0.85066（12）, c = 0.8973（2） nm,α= 84.97（2）, β =78.71（2）,γ= 80.12（2）°, Mr = 437.34, V= 0.49160（17） nm^3, Z = 1, Dc = 1.477 g/cm^3, F（000） = 230, R = 0.0422 and wR = 0.1290. In the structure, the central Ni atom is coordinated in a slightly distorted square plane by four S atoms from two bidentate S2CNC4H8NC2H5 ligands with the four Ni-S bond distances in the range of 0.22065（10）～0.22076（9） nm. The IR and FT-Raman spectral data are in agreement with the structural data. Thermal analysis indicates that the title compound decomposes completely at the temperature of 799.88℃, leaving NiS.

关键词： crystal structure N-ethylpiperazine nickel complex FT-Raman

Shadowing and Inverse Shadowing for C^1 Endomorphisms

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Acta Mathematica Sinica,English Series 2006年第5期22卷 1321-1328页

作者： Yu Jun ZHU Jin lian ZHANG lian Fa he College of Mathematics and Information Science Hebei Normal University Shijiazhuang 050016 P. R. China School of Mathematical Sciences Peking University Beijing 100871 P. R. China

In this paper, we consider the shadowing and the inverse shadowing properties for C^1 endomorphisms. We show that near a hyperbolic set a C^1 endomorphism has the shadowing property, and a hyperbolic endomorphism has the inverse shadowing property with respect to a class of continuous methods. Moreover, each of these shadowing properties is also ＂uniform＂ with respect to C^1 perturbation.

关键词： shadowing property inverse shadowing property endomorphism Hyperbolic set

Crystal Structure and Characterization of Bis(4-isoniazidylthioformyl) Disulfide Hydration Sodium Coordination Polymer:n[(4-Pyridyl-CONHNCS_2)_2^(2-)]·[Na_2(H_2O)_8^(2+)]_n

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Chinese Journal of Structural Chemistry 2006年第6期25卷 740-746页

作者： WANG Ying BEI Feng-Li YAN lian-he School of Chemical Engineering Nanjing Universityof Science and Technology Nanjing 210094 China

The title compound has been prepared and characterized by elemental analysis, infrared spectra, NMR and thermal analyses, and its crystal structure was determined by X-ray diffraction method. The crystal crystallizes in the monoclinic system, space group C2/c with a = 2.3066（5）, b = 0.53320（ 11）, c = 2.3236（5） nm,β= 102.76（3）°, V = 2.7872（ 10） nm^3, Mr = 612.67, Z = 4, Dc = 1.460 g/cm^3, R = 0.0570 and wR = 0.1271. In the title compound, two 4-isoniazidylthioformyl units are bridged by S-S bond （0.2037（3） nm）. The Na ions are linked by O（4）, O（4A）, O（1） and O（1A） to form a one-dimensional hydration sodium coordination polymer. The Na ion is coordinated by a meridional arrangement of the six O atoms to assume a slightly distorted octahedron as a result of intermolecular hydrogen bonds. The thermal analytical data indicate that it decomposes completely at the temperature of 609.26 ℃.

关键词： crystal structure bridging isoniazide coordination polymer

Melt electrospinning of daunorubicin hydrochloride-loaded poly (ε-caprolactone) fibrous membrane for tumor therapy

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Bioactive Materials 2017年第2期2卷 96-100页

作者： he lian Zhaoxu Meng Department of Biomedical Engineering School of Medical DevicesShenyang Pharmaceutical UniversityShenyang110016China

Daunorubicin hydrochloride is a cell-cycle non-specific antitumor drug with a high therapeutic *** present study outlines the fabrication of daunorubicin hydrochloride-loaded poly (ε-caprolactone)(PCL) fibrous membranes by melt electrospinning for potential application in localized tumor *** diameters of the drug-loaded fibers prepared with varying concentrations of daunorubicin hydrochloride(1, 5, and 10 wt%) were 2.48 ± 1.25, 2.51 ± 0.78, and 2.49 ± 1.58 μm, respectively. Fluorescenceimages indicated that the hydrophobic drug was dispersed in the hydrophilic PCL fibers in theiraggregated state. The drug release profiles of the drug-loaded PCL melt electrospun fibrous membraneswere approximately linear, with slow release rates and long-term release periods, and no observed burstrelease. The MTT assay was used to examine the cytotoxic effect of the released daunorubicin hydrochlorideon heLa and glioma cells (U87) in vitro. The inhibition ratios of heLa and glioma cells followingtreatment with membranes prepared with 1, 5, and 10 wt% daunorubicin hydrochloride were 62.69%,76.12%, and 85.07% and 62.50%, 77.27%, and 84.66%, respectively. Therefore, PCL melt electrospun fibrousmembranes loaded with daunorubicin hydrochloride may be used in the local administration ofoncotherapy.

关键词： Melt electrospinning Drug delivery system Poly(ε-caprolactone) Daunorubicin hydrochloride Tumor therapy

Paternal transgenerational glucose intolerance with epigenetic alterations in second generation offspring of GDM

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Asian Journal of Andrology 2013年第4期15卷 451-452页

作者： Guo-lian Ding he-Feng Huang Women's Hospital School of Medicine ZhejiangUniversity Hangzhou 310006 China

Gestational diabetes mellitus （GDM） has been shown to be associated withhigh risk of diabetes in offspring. In addi tion to intergenerational transmission （F1 offspring）, intrauterine hyperglycemia also has effects on the second generation （F2 off spring）. However, the mechanisms involved and the possibilities of transgenerational transmission are still unclear. In a recent study published in Diabetes, we have uti lized GDM mouse model to identify hyper glycemic intrauterine environment causing a high risk of diabetes in offspring by alter ing epigenetic modification. Furthermore, the results indicate that the abnormality of phenotype and imprinted genes expression are more obvious in male offspring than that of female. The changes of epigenetics in sperm may contribute to transgenera tional transmission. A growing body of research suggests that exposure to the abnormal environment in uterus can lead to chronic health problems later in life.1 Intrauterine hyperglycemia is a major characteristic of GDM and has been suggested as an important determinative fac tor for the risk of diabetes in adulthood, it1 addition to the effects of genetic factors.2 The mechanism involved in the association between intrauterine hyperglycemia and a high risk of diabetes in offspring remains unclear.3 In mammals, epigenetic reprogram ming is involved in germ cells and early embryonic development.4＇5 Because erasure and establishment of the genomic imprints for some imprinted genes begin when migra tory primordial germ ceils enter the embry onic genital ridge through gametogenesis, epigenetic abnormalities that occur duringthis phase may be involved in transgenera tional transmission.6 In the study, Ding et al.7 established a GDM mouse model of intrauterine hypergly cemia. The female （9） and male （or） F1 adults of control and GDM mice were intercrossed to obtain F2 offspring of four groups：（i） C0＂ C9; （ii） CCYGDMg; （iii） GDMCrCg; and （iv） GDMcYGDMg. We found that intrau terine hypergl

关键词： Paternal transgenerational intolerance

An improved algorithm for retrieving thin sea ice thickness in the Arctic Ocean from SMOS and SMAP L-band radiometer data

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Acta Oceanologica Sinica 2024年第3期43卷 127-138页

作者： lian he Senwen Huang Fengming Hui Xiao Cheng School of Geospatial Engineering and Science Sun Yat-Sen Universityand Southern Marine Science and Engineering Guangdong Laboratory(Zhuhai)Zhuhai 519082China Key Laboratory of Comprehensive Observation of Polar Environment(Sun Yat-Sen University) Ministry of EducationZhuhai 519082China

The aim of this study was to develop an improved thin sea ice thickness(SIT)retrieval algorithm in the Arctic Ocean from the Soil Moisture Ocean Salinity and Soil Moisture Active Passive L-band radiometer *** SIT retrieval algorithm was trained using the simulated SIT from the cumulative freezing degree days model during the freeze-up period over five carefully selected regions in the Beaufort,Chukchi,East Siberian,Laptev and Kara seas and utilized the microwave polarization ratio(PR)at incidence angle of 40°.The improvements of the proposed retrieval algorithm include the correction for the sea ice concentration impact,reliable reference SIT data over different representative regions of the Arctic Ocean and the utilization of microwave polarization ratio that is independent of ice *** relationship between the SIT and PR was found to be almost stable across the five selected *** SIT retrievals were then compared to other two existing algorithms(i.e.,UH_SIT from the University of Hamburg and UB_SIT from the University of Bremen)and validated against independent SIT data obtained from moored upward looking sonars(ULS)and airborne electromagnetic(EM)induction *** results suggest that the proposed algorithm could achieve comparable accuracies to UH_SIT and UB_SIT with root mean square error(RMSE)being about 0.20 m when validating using ULS SIT data and outperformed the UH_SIT and UB_SIT with RMSE being about 0.21 m when validatng using EM SIT *** proposed algorithm can be used for thin sea ice thickness(he Arctic Ocean and requires less auxiliary data in the SIT retrieval procedure which makes its implementation more practical.

关键词： Arctic sea ice sea ice thickness remote sensing Soil Moisture Active Passive(SMAP) Soil Moisture Ocean Salinity and Soil(SMOS)

Cosmic Neutrino Time Delay Relative to Photons

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Chinese Physics Letters 2004年第7期21卷 1236-1239页

作者： LUOXin-lian PENGQiu-he ZHANGLing-Di BAIHua CHOUChih-Kang DepartmentofAstronomy NanjingUniversityNanjing210093

By solving the Friedmann-Robertson-Walker (FRW) geodesic equations for a free test particle with finite mass, we extend the widely used time-of-flight delay expression, which is just valid locally in the neighbourhood of our Galaxy, to the cosmic distance scale. If neutrino masses are known, this may provide a potential method to determine a large scale geometry of the Universe.

关键词： Gravitation and cosmology Particle physics and field theory Astrophysics and astroparticles

Performance Study of the MPC based on BPNN Prediction Model in Thermal Management System of Battery Electric Vehicles

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Journal of Thermal Science 2024年第6期33卷 2318-2335页

作者： he lian'ge JING Haodong ZHANG Yan LI Pengpai GU Zihan Key Laboratory of Advanced Manufacture Technology for Automobile Parts(Chongqing University of Technology) Ministry of EducationChongqing 400054China Ningbo Shenglong Group Co. Ltd.Ningbo 315104China Chongqing Tsingshan Industrial Co. Ltd.Chongqing 402761China

In this paper,a model predictive control(MPC)based on back propagation neural network(BPNN)prediction model was proposed for compressor speed control of air conditioning system(ACS)and battery thermal management system(BTMS)coupling system of battery electric vehicle(BEV).In order to solve the problem of high cooling energy consumption and inferior thermal comfort in the cabin of the battery electric vehicle thermal management system(BEVTMS)during summer time,this paper combines the respective superiorities of artificial neural network(ANN)predictive modeling and MPC,and creatively combines the two methods and uses them in the control of ***,based on ANN and heat transfer theory,BPNN prediction model,ACS and BTMS coupling system were established and ***,a mathematical method of MPC was established to control the speed of the ***,the state parameters of the coupled system were predicted using a BPNN prediction model,and the predicted values were passed to the MPC,thus achieving accurate control of the compressor speed using the ***,the effects of PID control and MPC based on BPNN prediction model on thermal comfort of cabin and compressor energy consumption at different ambient temperatures were compared in simulation under New European Driving Cycle(NEDC)*** results showed for the constructed BPNN prediction model predicted and tested values of the selected parameters the mean squared error(MSE)ranged from 2.498%to 8.969%,mean absolute percentage error(MAPE)ranged from 4.197%to 8.986%,and mean absolute error(MAE)ranged from 3.202%to 8.476%.At ambient temperatures of 25℃,35℃ and 45℃,the MPC based on the BPNN prediction model reduced the cumulative discomfort time in the cabin by 100 s,39 s and 19 s,respectively,compared with the PID *** three NEDC conditions,the energy consumption is reduced by 1.82%,2.35%and 3.48%,*** the ambient temperature was 35℃,the MPC based on BPNN prediction model

关键词： air conditioning system battery thermal management system back propagation neural network model predictive control battery electric vehicle