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Fly Ash/Paraffin composite Phase change Material Used to Treat Thermal and Mechanical Properties of Expansive Soil in cold Regions

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Journal of Renewable Materials 2022年第4期10卷 1153-1173页

作者： Yong chen Yinghao huang Min Wu Shuo Wang Geotechnical Engineering Department Nanjing Hydraulic Research InstituteNanjing210024China State Key Laboratory of hydrology-Water Resources and hydraulic Engineering Science Nanjing210029China

Phase change materials(PcMs)can store large amounts of energy in latent heat and release it during phase changes,which could be used to improve the freeze-thaw performance of *** composite phase change material was prepared with paraffin as the PcM and 8%class c fly ash(cFA)as the supporting *** tests were conducted to reveal the influence of phase change paraffin composite class c fly ash(cFA-PcM)on the thermal properties,volume changes and mechanical properties of expansive *** results show that PcM failed to establish a good improvement effect due to *** can effectively adsorb phase change materials,and the two have good ***-PcM reduces the volume change and strength attenuation of the soil,and 8 wt.%PcM is the optimal ***-PcM turns the phase change latent heat down of the soil and improves its thermal ***-PcM makes the impact small of freeze-thaw on soil pore structure damage and improves soil volume change and mechanical properties on a macroscopic *** addition,cFA-8 wt.%PcM treated expansive soil has apparent advantages in resisting repeated freeze-thaw cycles,providing a reference for actual engineering design.

关键词： composite phase change material freeze-thaw performance expansive soil thermal properties mechanical properties

Phase Evolution and Magnetic Studies of La and Refractory Metals co-substituted α-Fe/R_2Fe_(14)B-type Nanocomposites

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Journal of Materials Science & Technology 2000年第2期16卷 102-106页

作者： W. c. changt, S.h. Wang, S.J. chang and M. Y. Tsai (Department of Physics, chung cheng University, Ming-hsiung, chia-Yi, 621, Taiwan-china Q.chen) (Rhodia Inc., Rare Earths and Gallium, cN 7500, cranbury, New Jersey 08512, U.S.A.) Department of Physics Chung Cheng University Ming-Hsiung Chia-Yi 621 Taiwan Rhodia Inc. Rare Earths and Gallium CN 7500 Cranbury NJ 08512 United States

Phase evolution and magnetic properties of (Nd_o.95La_0.05)9.5-11Febal.M_2B10.5. where M=cr, Ti, Nb, V, Mo, Zr, hf, Ta, Mn or W, melt spun ribbons have been investigated. Almost all the alloy ribbons. except for(Nd_0.95La_0.05)_9.5Fe_78M_2B_10.5(M=Mo and Mn),consist merely two magnetic phases, namely α-Fe and R_2Fe_14B, which display a better combination of _ih_c and magnetic energy product. Remanence (Br) and coercivity (i_h_c) values in the range of 8.0 to 9.1 kG and 9.5 to 18.9 kOe. respectively, can be achieved. Among compositions studied, the Ti and W-substitutions were found to be most effective in increasing the Br and i_h_c, respectively. For a fixed refractory metal substitution, namely, M=c_r, Ti or Nb, an increase in the total rare earth concentration resulted in nanocomposites of small grain sizes and a high volume fraction of the R_2Fe_14B phase, leading to an increase in the magnetic properties.

关键词： Fe/R2Fe B-type Nanocomposites Phase Evolution and Magnetic Studies of La and Refractory Metals co-substituted type La

GLOBAL WELL-POSEDNESS FOR FRAcTIONAL NAVIER-STOKES EQUATIONS IN VARIABLE EXPONENT FOURIER-BESOV-MORREY SPAcES

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Acta Mathematica Scientia 2021年第1期41卷 164-176页

作者： Muhammad Zainul ABIDIN Jiecheng chen college of Mathematics and computer Science Zhejiang Normal UniversityJinhua 321004China

In this paper we study the cauchy problem of the incompressible fractional Navier-Stokes equations in critical variable exponent Fourier-Besov-Morrey space F N^(s(·))p(·),h(·),q(R^(3))with s(·)=4-2α-3/p(·).We prove global well-posedness result with small initial data belonging to FN^(4-2α-3/p(·))p(·),h(·)q(R^(3)).The result of this paper extends some recent work.

关键词： fractional Navier-Stokes equations global well-posedness Fourier-Besov-Morrey space

Terrestrial vegetation carbon sinks in china,1981―2000

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Science china Earth Sciences 2007年第9期50卷 1341-1350页

作者： FANG JingYun GUO ZhaoDi PIAO ShiLong chen AnPing Department of Ecology College of Environmental Scienceand Key Laboratory for Earth Surface Processes of the Ministry of EducationPeking UniversityBeijing 100871China

Using china's ground observations,e.g.,forest inventory,grassland resource,agricultural statistics,climate,and satellite data,we estimate terrestrial vegetation carbon sinks for china's major biomes between 1981 and *** main results are in the following:(1)Forest area and forest biomass car-bon(c)stock increased from 116.5×10^(6) ha and 4.3 Pg c(1 Pg c=10^(15) g c)in the early 1980s to 142.8×10^(6) ha and 5.9 Pg c in the early 2000s,*** biomass carbon density increased form 36.9 Mg c/ha(1 Mg c=10^(6) g c)to 41.0 Mg c/ha,with an annual carbon sequestration rate of 0.075 Pg c/***,shrub,and crop biomass sequestrate carbon at annual rates of 0.007 Pg c/a,0.014―0.024 Pg c/a,and 0.0125―0.0143 Pg c/a,respectively.(2)The total terrestrial vegetation c sink in china is in a range of 0.096―0.106 Pg c/a between 1981 and 2000,accounting for 14.6%―16.1%of carbon dioxide(cO_(2))emitted by china's industry in the same *** addition,soil carbon sink is estimated at 0.04―0.07 Pg c/***,carbon sequestration by china's terrestrial ecosystems(vegetation and soil)offsets 20.8%―26.8%of its industrial cO_(2) emission for the study period.(3)considerable uncertainties exist in the present study,especially in the estimation of soil carbon sinks,and need further intensive investigation in the future.

关键词： carbon sink china crops forests grasslands shrubs soils terrestrial ecosystems

hierarchical hesitant fuzzy K-means clustering algorithm

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Applied Mathematics(A Journal of chinese Universities) 2014年第1期29卷 1-17页

作者： chen Na XU Ze-shui XIA Mei-mei School of Economics and Management Southeast University School of Applied Mathematics Nanjing University of Finance and Economics Business School Sichuan University School of Economics and Management Tsinghua University

Due to the limitation and hesitation in one＇s knowledge, the membership degree of an element to a given set usually has a few different values, in which the conventional fuzzy sets are invalid. hesitant fuzzy sets are a powerful tool to treat this case. The present paper focuses on investigating the clustering technique for hesitant fuzzy sets based on the K-means clustering algorithm which takes the results of hierarchical clustering as the initial clusters. Finally, two examples demonstrate the validity of our algorithm.

关键词： 90B50 68T10 62h30 hesitant fuzzy set hierarchical clustering K-means clustering intuitionisitc fuzzy set

The Non-fragile Robust h∞ controller design with system uncertainty

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The Non-fragile Robust H∞ controller design with system unc...

The effect of anodizing temperature on the structure and electrical properties of Al-Ti composite oxide film

第25届中国控制与决策会议

作者： YANG chang-wei chen Jie The 365 institute Northwestern Polytechnical University School of Aeronautics Northwestern Polytechnical University

ISBN: (纸本)9781467355322

This paper presents a non-fragile robust h∞ controller design with system uncertainty. With the additive controller gain variations, the necessary and sufficient conditions for the existence of non-fragile state feedback controller are given and transformed to the LMI problems, which simplifies the solutions to get non-fragile robust h∞ state feedback controllers. The flight control simulation results show the reliability and validity of the method.

关键词： non-fragile control, h control, robust control, Linear Matrix Inequality (LMI)

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Science china(Technological Sciences) 2005年第6期48卷 612-621页

作者： chen Jinju YANG Bangchao JIANG Meilian FENG Zhesheng School of Micro-electronics and Solid Electronics University of Electronics Science and Technology of ChinaChengdu 610054China

The Al?Ti composite oxide films with high dielectric constant were prepared by hydrolysis precipitation and anodizing. The growth, structure and electrical properties of the Al?Ti composite oxide films formed at different anodizing temperatures from 25°c to 85°c have been studied by dissolution of anodic oxide films, Auger electron spectroscopy (AES), and electrical measurements. With the anodizing temperature increasing, the film growth rate increases, the structure of two layers in the Al?Ti composite oxide film converts into three layers, I–V characteristics change evidently, and the specific capacitance achieves a peak value at about 75°c. The local breakdown in the composite oxide films formed at 50°c occurs obviously, which may be contributed to the lowest leakage current and the highest withstanding voltage.

关键词： anodizing temperature Al-Ti composite oxide film structure electrical properties

Synthesis of Aminoalkyl-substituted Polymethoxychalcone Derivatives and Their Antiproliferative Activities Against Three human cancer cell Lines

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chemical Research in chinese Universities 2016年第5期32卷 754-759页

作者： chen Mingxia ShI Ling TANG Jiaqing WANG Qiuan college of chemistry and chemical Engineering Hunan University Changsha 410082 P. R. China

Two novel series of sixteen aminoalkyl-substituted polymethoxychalcone derivatives 2a--2h and 3a--3h were synthesized from 2＇-hydroxy-3,4,5,4＇,6＇-pentamethoxy chalcone（1） through extending alkoxy side chain at the 2＇-position, and introducing amine hydrogen bond receptor at the end of the side chain. The structures of all the synthesized compounds were confirmed by 1h NMR, 13c NMR and MS techniques. Furthermore, all the compounds were tested for antiproliferative activities in vitro against a panel of three human cell lines（heLa, hcc1954 and SK-OV-3） via ccK-8 assay. The results show that all the target compounds exhibit antiproliferative activities against the three human cancer cells with Ic50 values of 4.62-48.21μmol/L, except compound 2h against SK-OV-3 cells. Most of these compounds were more active when compared to the positive control cis-Platin.

关键词： Polymethoxychalcone Aminoalkyl-substituted derivative Antiprolifertive activity

Photocatalytic Reduction of Nitro compounds Using TiO2 Photocatalyst by UV and Vis Dye-sensitized Systems

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chinese Journal of chemistry 2011年第3期29卷 399-404页

作者： chen, Shifu Zhang, huaye Yu, Xiaoling Liu, Wei Department of chemistry Huaibei Normal University Huaibei Anhui 235000 China

Nitro-aromatic compounds can be photocatalytically reduced into the corresponding amine-aromatic com- pounds using TiO2 as a photocatalyst in the UV/TiO2/holes scavenger and Vis/TiO2/dye-sensitized systems. In the UV/TiO2/holes scavenger system, reaction substrate alcohols such as methanol could be used as the holes scavengers, and in the Vis/TiO2/dye-sensitized system, substrate alcohols could be oxidized to the corresponding aldehydes with high selectivity. When methanol was used as the holes scavengers and the illumination time was 6 h, 87.2% ofp-nitrotoluene could be photocatalytically reduced into p-toluidine. In the Vis/TiO2/dye-sensitized system, the effect of aromatic alcohols for the photocatalytic reduction of nitrobenzene was better than that of other alcohols At the same time, aromatic alcohols can be easily oxidized, and the production efficiencies of the corresponding aldehydes were higher than those of other alcohols. The possible reaction mechanisms were also proposed.

关键词： photochemistry synthetic method nitro-aromatic compounds UV/TiO2/holes scavenger Vis/TiO2/dye-sensitized systems