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Degree One Loading by Pressure Variations at the CMB

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Journal of Earth Science 2013年第5期24卷 736-749页

作者： ming fang Bradford H Hager Weijia Kuang Department of Earth Atmospheric & Planetary Sciences Massachusetts Institute of Technology Planetary Geodynamics Laboratory NASA Goddard Space Flight Center

Hemispherical asymmetry in core dynamics induces degree-1 pressure variations at the core mantle boundary （CMB）, which in turn deforms the overlaying elastic mantle, at the same time keeps center of mass of the whole Earth stationary in space. We develop a systematic procedure to deal with the degree-1 CMB pressure loading. We find by direct calculation a surprisingly negative load Love number h1=-1.425 for vertical displacement. Further analysis indicates that the negative hi corre- sponds to thickening above the positive load that defies intuition that pressure inflation pushes over- laying material up and thins the enveloping shell. We also redefine the pressure load Love numbers in general to enable comparison between the surface mass load and the CMB pressure load for the whole spectrum of harmonic degrees. We find that the gravitational perturbations from the two kinds of loads at degrees n〉l are very similar in amplitude but opposite in sign. In particular, if the CMB pressure variation at degree 2 is at the level of -1 hpa/yr （1 cm water height per year）, it would perturb the variation of Earth＇s oblateness, known as the J2, at the observed level.

关键词： Degree One Loading by Pressure Variations at the CMB MRSP

Investigation on Viscoelasticity of Waterborne Polyurethane with Azobenzene-containing Pendant Groups under Ultraviolet and Visible-light Irradiation

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Chinese Journal of Polymer Science 2019年第12期37卷 1267-1272,I0007页

作者： Yi-Jun Liu Dong Liu Si-Han Li Hua-Qing Liang fang-ming Zhu GDHPPC Lab School of ChemistrySun Yat-sen UniversityGuangzhou 510275China Key Lab for Polymer Composite and Functional Materials of Ministry of Education School of ChemistrySun Yat-sen UniversityGuangzhou 510275China

In this study,a novel waterborne polyurethane(WPU)with azobenzene-containing(azo-containing)pendant groups was synthesized by isophorone diisocyanate,long-chain diol of polycaprolactone,2-ethyl-2-methyl-butanoic acid(2,2-dimethylolpropionic acid),10-(4-(phenyldiazenyl)phenoxy)decyl-3-hydroxy-2-(hydroxymethyl)-2-methylpropanoate,and N,N-diethyl-ethanamine(triethylamine).Moreover,the influence of ultraviolet and visible(UV-Vis)light irradiation on the viscoelasticity of azo-containing WPU film in terms of the reversible trans-cis photoisomerization of azo-containing pendant groups was investigated by UV-Vis light spectroscopy,atomic force microscopy,and dynamic thermomechanical *** results revealed that the adhesion of azo-containing WPU with single crystal silicon atomic force microscope probe was about 13 n N when irradiated by 450 nm Vis light for 60 s at 25°***,the adhesion increased to 82 n N after irradiation with 365 nm UV light for 60 s at 25°*** addition,the azo-containing WPU presented a photo-induced reversible transition of tensile modulus and tanδin the range from about 2 MPa to 22 MPa and 6000 to 0.35 with UV-Vis light cyclic irradiation for 120 s at 25°C,respectively.

关键词： Waterborne polyurethane Viscoelasticity Photoisomerization Azobenzene

Dielectric monitoring method for the drug release mechanism of drug-loading chitosan microspheres

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Chinese Science Bulletin 2010年第13期55卷 1246-1254页

作者： fang ming GAO JinLong WANG Sheng LIAN YiWei ZHAO KongShuang College of Chemistry Beijing Normal University Beijing 100875 China

The chitosan microspheres loaded with model drug, salicylate molecular, are prepared, and the dielectric spectroscopy of this kind of suspension is measured, meanwhile a significant relaxation is observed for the microspheres suspension. By the modeling analytic of the relaxation, the parameters, which can reflect the properties of microspheres and continuous medium, are obtained. Furthermore, the releasing process of microspheres in aqueous phase is monitored real-timely, namely, by analyzing the time-dependent variation of the parameters reflecting the relaxation characteristics and electrical parameters in each phase the releasing process is detected. The research shows that the controlled release process of chitosan microspheres loaded with salicylate in aqueous phase is divided into three phases according to different releasing mechanisms. At the release stage, the quantitative relation between the phase parameters obtained by dielectric analysis and the amount of the salicylate carried in microspheres was derived, and a real-time monitoring method was established through releasing material in the microspheres at different times obtained by measuring and analyzing the dielectric spectroscopy.

关键词：壳聚糖微球连续介质监测方法释放机制药物载药释放过程光谱测量

Ferroelectricity based on coordination compound:Transition metal Co(Ⅱ) sulfates templated by homochiral2-methylpiperazine(C_5H_(14)N_2)[Co(H_2O)_6](SO_4)_2

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Chinese Chemical Letters 2014年第6期25卷 967-972页

作者： Li-Zhuang Chen Deng-Deng Huang Qi-Jian Pan fang-ming Wang School of Biology and Chemical Engineering Jiangsu University of Science and Technology State Key Laboratory of Coordination Chemistry School of Chemistry and Chemical EngineeringNanjing University

Reacting homochiral （R）-2-methylpiperazine with cobalt sulfate heptahydrate by the solution method in the presence of concentrated sulfuric acid （H2SO4） yielded two coordination compounds （C5H14N2） [CO（H2O）6]（SO4）2 （1 and 2）. They are polymorphs, but their hydrogen bonds structure differ significantly. Both 1 and 2 crystallize in chiral space group P21 which is related with point group C2, and experimental results suggest that 1 displays ferroelectric behaviors.

关键词： Co(Ⅱ) compound Homochiral Ferroelectric Dielectric

Clinical use of low-dose aspirin for elders and sensitive subjects

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World Journal of Clinical Cases 2019年第20期7卷 3168-3174页

作者： Yan Zhang Xiang-ming fang Guo-Xun Chen Department of Gastroenterology Affiliated Puren Hospital of Wuhan University of Science and TechnologyWuhan 430000Hubei ProvinceChina Department of Nutrition University of Tennessee at KnoxvilleKnoxvilleTN 37996United States

The use of low-dose aspirin(LDA)has been a common preventive measure to reduce the risk of cardiovascular *** is attributed to aspirin’s ability to inhibit platelet *** the other hand,the use of LDA in human subjects has been associated with the development of gastrointestinal injuries like ulcer and bleeding,especially for those sensitive subjects such as elder human *** opinion review will summarize the recent clinical reports regarding the use of LDA and the development of gastrointestinal conditions in *** on these reports,it seems that the use of LDA is commonly associated with gastrointestinal injuries,and stopping its use leads to recovery in elderly ***,we would like to suggest that gastroduodenal health and conditions should be seriously taken into consideration when LDA is recommended to the elderly,or other alternative means to reduce the risk of cardiovascular events such as nutritional interventions should be suggested.

关键词： Low-dose aspirin Gastrointestinal damages Upper gastrointestinal bleeding Human subjects Chinese elders

Science Letters:Hydrogen transfer reduction of ketones using formic acid as a hydrogen donor under hydrothermal conditions

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Journal of Zhejiang University-Science A(Applied Physics & Engineering) 2009年第11期10卷 1631-1635页

作者： Zheng SHEN fang-ming JIN Ya-lei ZHANG Bing WU Jiang-lin CAO State Key Laboratory of Pollution Control and Resources Reuse MOE Key Laboratory of Yangtze River Water Environment College of Environmental Science and Engineering Tongji University Shanghai 200092 China

The hydrothermal experiments with ketones and formic acid showed that the hydrogen transfer reduction of ketones can be conducted using formic acid as a hydride donor in the presence of NaOH at 300 ℃. The yield of alcohols was considerably higher at a much lower ratio of hydrogen source to ketones than the traditional Meerwein-Ponndorf-Verley （MPV） reduction, reaching 60% for isopropanol from acetone and 70% for lactic acid from pyruvic acid. Water molecules may act as a catalyst in the hydrogen transfer reduction of ketones under hydrothermal conditions.

关键词： Hydrogen transfer reduction Formic acid Ketone Hydrothermal reaction

The first 2D organic-inorganic hybrid relaxor-ferroelectric single crystal

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Science China Chemistry 2023年第2期66卷 466-474页

作者： Wenjuan Wei Hongqiang Gao ming fang Yang Yang Yan Guan Yen Wei Yunzhi Tang Department of Chemistry Tsinghua UniversityBeijing100084China Faculty of Materials Metallurgy and Chemistry Jiangxi University of Science and TechnologyGanzhou341000China Institute of Nuclear and New Energy Technology Tsinghua UniversityBeijing100084China The Analytical Instrumentation Center of Peking University the Center for Physicochemical Analysis and Measurements in ICCASBeijing100871China

Inorganic relaxor ferroelectric solid solution single crystals are spurring new generations of high performance electromechanical devices,including transducers,sensors,and actuators,due to their ultrahigh electric field induced strain,large piezoelectric constant,high electromechanical coupling factor and low dielectric ***,relaxor ferroelectric single crystals found in organic-inorganic hybrid perovskites are very limited,but achieving these superior properties in them will be of great significance in the design of modern functional ***,here the first two-dimensional(2D)organic-inorganic hybrid relaxor ferroelectric single crystal,[Br(CH_(2))_(3)NH_(3)]_(2)PbBr_(4)(BPA_(2)-PbBr_(4),BPA=3-bromopropylamine),achieves some of superior ***,BPA_(2)-PbBr_(4)reveals a successive relaxor ferroelectric-ferroelectric-paraelectric phase transitions accompanying by a large degree of relaxationΔT_(relax)=61 K and ultralow energy loss(tanδ<0.001).Meanwhile,it exhibits a superior second harmonic generation(SHG)effect with maximum value accounts for 95%of the standard KDP due to great deformation of structure(3.2302×10^(-4)).In addition,temperature dependent luminescence spectra(80-415 K)exhibit fluorescence and phosphorescence overlapping emission originated from inorganic and organic components with the nanosecond-scale short lifetime and the millisecond-scale long lifetime,respectively,and the color of the emitted light is continuously adjustable,which is the first to achieve luminescence and relaxor ferroelectricity compatibility.

关键词： 2D organic-inorganic hybrid perovskites ferroelectrics relaxor ferroelectrics paraelectrics luminescence

Bio-inspired Backstepping Adaptive Sliding Mode Control for Parallel Mechanism with Actuation Redundancy

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International Journal of Automation and computing 2014年第5期11卷 555-564页

作者： Xue-Mei Niu Guo-Qin Gao Xin-Jun Liu Zhi-ming fang School of Electrical and Information Engineering Jiangsu University Department of Mechanical Engineering Tsinghua University

This paper presents a bio-inspired backstepping adaptive sliding mode control strategy for a novel 3 degree of freedom(3-DOF) parallel mechanism with actuation redundancy. Based on the kinematic model and the dynamic model, a sliding mode controller is designed to assure the tracking performance, and an adaptive law is introduced to approximate the system uncertainty including parameters variation, external disturbances and un-modeled part. Furthermore, a bio-inspired model is introduced to solve the inherent chattering problem of sliding mode control and provide a chattering free control. The simulation and experimental results testify that the proposed bio-inspired backstepping adaptive sliding mode control can achieve better performance(the tracking accuracy,robustness, response speed, etc.) than the conventional slide mode control.

关键词： Parallel mechanism redundant actuation kinematics analysis dynamics analysis adaptive sliding mode control bioinspired model

Compound-specific carbon isotope compositions of individual long-chain n-alkanes in severe Asian dust episodes in the North China coast in 2002

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Chinese Science Bulletin 2006年第17期51卷 2133-2140页

作者： GUO Zhigang LI Juyuan FENG Jialiang fang ming YANG Zuosheng College of Marine Geosciences Ocean University of China Qingdao 266003 China Institute of Geology Shengli Oil-field Company Petrochemical Corporation of China Dongying 257015 China Institute for Environment and Sustainable Development Hong Kong University of Science and Technology Clear Water Bay KowloonHong Kong China

The molecular compositions and com- pound-specific carbon isotope compositions of indi- vidual long-chain n-alkanes of atmospheric aerosols collected during two severe Asian dust episodes in Qingdao in spring of 2002 were analyzed using gas chromatography/mass spectrometry (GC/MS) and gas chromatography/isotope ratio mass spectrometry (GC/IRMS). Typical plant wax n-alkanes (C29 and C31) had lower δ 13C values than those from anthropo- genic (engine exhaust) sources (C21―C23). The av- erage δ 13C value of plant wax n-alkane C29 in non-dust episode periods was -30.5‰ (?30.3‰― ?31.9‰), while -31.3‰ (?31.1‰―?31.5‰) in dust episode periods; for C31, it was ?31.4‰ (?31.1‰― ?33.0‰) in non-dust episode periods, and ?31.7‰ (?31.3‰―?32.6‰) in dust episode periods. Plant wax in the dust episode samples was mainly from herbaceous plants via long-range transport, while local plant wax was mainly from deciduous plants and woody plants. In North China coast, 83.3% of the plant wax in the severe dust episode samples was from C3 plants while 80.0% for the non-dust samples, indicating that plant wax transported to the north- western Pacific Ocean by airborne dust from East Asia was mainly from C3 plants. The results suggestthat the molecular and molecular-isotopic composi- tions of individual long-chain n-alkanes can, as an effective indicator, identify the terrestrial organic components in the dust from East Asia and sedi- ments in the northwest Pacific Ocean.

关键词：亚洲尘暴华北地区碳同位素 GC-MS GC-IRMS