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Properties of Xanthoceras sorbifolia Husk Fibers With Chemical Treatment for Applications in Polymer Composites

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Journal of Materials Science & Technology 2015年第2期31卷 164-170页

作者： Hongyu wang Xudan Yao Guoxin Sui Liming Yin lihua wang Institute of Metal Research Chinese Academy of Sciences Shenyang Institute of Applied Ecology Chinese Academy of Sciences

Surface science of natural fibers plays an important role in polymer/natural fiber composites. The Xanthoceras sorbifolia husk fibers were selected and chemically treated by sodium hydroxide(Na OH) solution,coupling agents,their combination,and the mixtures of acetic acid with hydrogen peroxide,respectively. 3-aminopropyltriethoxysilane(KH550),γ-methacryloxypropyltrimethoxylsilane(KH570) and organic titanate(JN-9A) were used as coupling agents in this work. Cellulose content was found to be increased after alkalization due to the removal of the non-cellulose substances,which was evidenced by attenuated total reflectance-Fourier transform infrared(ATR e FTIR) spectroscopy spectrum analysis and thermogravimetric analysis(TGA) measurements. The highest cellulose content was obtained in the bleached fibers. TGA analysis revealed an improvement in thermal stability of the treated fibers,especially for alkali-KH570 treated fibers. The tensile strength of the alkali-KH570 treated fiber and the alkali-bleached fiber were higher than that of other fibers due to high cellulose content and high crystallinity.

关键词： Xanthoceras sorbifolia husk fibers Chemical treatm

Effects of RE,V,Ti and B composite modification on the microstructure and properties of high chromium cast iron containing 3% molybdenum

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Rare Metals 2009年第6期28卷 606-611页

作者： GUO Erjun wang lihua wang Liping HUANG Yongchang School of Materials Science and Engineering Harbin University of Science and Technology Harbin 150080 China

The effects of RE, V, Ti and B on the microstructure and properties of high chromium cast iron containing 3% molybdenum under as-cast and heat treatment conditions were investigated with the method of comparing experiments. The results show that with the increase of RE content, the primary austenite of high chromium cast iron is obviously refined. The morphology of carbide is changed from netlike and lath to small multiangular isolated blocks or massive blocks, the isolated degree of carbide is improved obviously, and the size is significantly refined. The addition of V and B into high chromium cast iron can refine the microstmcture, reduce coarse columnar crystals and make the carbide smaller and uniform. Through composite modification with RE, V, Ti and B, the hardness, wear resistance and impact toughness of high chromium cast iron are increased conspicuously. After heat treatment, the hardness of high chromium iron is increased significantly, but the toughness and wear resistance do not show great improvement.

关键词： high-chromium cast iron rare earth composite modification microstructure mechanical properties

Relation between stabilization energy, crystal field coefficient and the magnetic exchange interaction for Tb^(3+) ion

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Rare Metals 2006年第Z1期25卷 602-604页

作者： ZHANG Xiangmu MA Wenjuan CUI Shuwen wang lihua Physics Department Cangzhou Normal College Cangzhou 061001 China Physics Department Cangzhou Normal College Cangzhou 061001 China Institute of Mechanics Chinese Academy of Sciences Beijing 100080 China Physics Department Cangzhou Normal College Cangzhou 061001 China

Based on a single ion model, Hamiltonian of the simplest form about magnetocrystalline anisotropy for Tb3+ ion was solved by using the numerical method. The relation between the stabilization energy, crystal field coefficient B20 and the magnetic exchange interaction was studied as temperature approaches to 0 K. The results show that the stabilization energy contributed by Tb3+ is linear with crystal field coefficient B20 approximately, but it is insensitive to the change of magnetic exchange interaction for the strong magnetic substances such as TbCo5, Tb2Co17 and Tb2Fe14B compounds.

关键词： single ion model magnetic exchange interaction crystal field coefficient stabilization energy

Analysis of rare earth elements in high purity europium oxide

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Rare Metals 2005年第3期24卷 216-220页

作者： LU Yiqiang CAO Yanqiu wang lihua XIN Renxuan Applied Science School University of Science and Technology Beijing Beijing 100083 China Institute of Nuclear Energy Technology Tsinghua University Beijing 100084 China

Five trace impurities as Ce, Pr, Sm, Gd, and Dy are separated from europium oxide with P507 extraction resin by extraction chromatography. When determined simultaneously by ICP-AES, the impurities show their recovery ratios between 88% and 105%. A lower than 10% relative standard deviation of these elements is obtained when their contents in europium oxide are 5μg/g. The satisfactory results indicate this simple method is sensitive and accurate. It has been employed in the analysis of these five rare earth elements in 99.99% europium oxide.

关键词： analytical chemistry rare earth elements separation ICP-AES extraction resin

Character of the Si and Al Phases in Coal Gangue and Its Ash

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Acta Geologica Sinica(English Edition) 2009年第6期83卷 1116-1121页

作者： wang lihua ZHAO Pengda LI Geng China University of Geosciences Beijing 100083 China School of Gemmology China University ofGeosciences Beijing 100083 China

Analysis of the Si and AI phases in coal gangue fuel and its ash is important for use of coal gangue ashes. A comprehensive study by theoretical and experimental analyses with differential thermal analysis, X-ray diffraction and Infrared Spectroscopy has been made in the present article to explore the diagram of the Si and Al phases in coal gangue fuel and its ashes. It is found that kaolinite and quartz are the main phases in coal gangue fuel. The ratio of moles A1203 to SiO2 （i.e., Al2O3 （mole） / SiO2 （mole）） is usually no more than 0.5 in most coal gangue fuel and its ashes. The kaolinit at about 984℃ releases a large quantity of SiO2, which makes calcine coal gangue more active than coal gangue itself. The relationship between the ratio A1203 （mole）]SiO2（mole）and the components of coal gangue ash is analyzed, resulting in a formula to calculate the quantity of each phase. Applying the formula to the testing samples from an electric plant in north China supports the above conclusions.

关键词： Si and AI phases Al2O3 (mole)/SiO2(mole) coal gangue fuel coal gangue ash

One-pot hydrothermal synthesis of hierarchical porous manganese silicate microspheres as excellent Fenton-like catalysts for organic dyes degradation

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Nano Research 2022年第4期15卷 2977-2986页

作者： Yuyu Zheng lihua wang Liyun Zhang Heng Zhang Wancheng Zhu Department of Chemical Engineering Qufu Normal UniversityQufu 273165China

Towards bottlenecks demonstrated by typical Fenton-like catalysts in advanced oxidation processes(AOPs)for wastewater treatment,novel hierarchical porousMn^(2+)Mn_(6)^(3+)SiO_(12)(Mn_(7)SiO_(12),MSO-12)microspheres(specific surface area:434.90 m^(2)·g^(-1),pore volume:0.78 cm^(3)·g^(-1))were rationally designed and achieved via a simple one-pot hydrothermal method(150℃ and 12.0 h)without any pre-prepared templates or organic solvents,by using abundant MnCl_(2)·4H_(2)O and Na_(2)SiO_(3)·9H_(2)O as the basic raw *** MSO-12 microspheres are confirmed as high-efficiency Fenton-like catalysts for degradation of organic dyes(methylene blue(MeB),Rhodamine B(RhB),and methyl blue(MB))in the presence of H_(2)O_(2),with impressively high specific consumption amount of MeB(R=12.35 mg·g^(-1)·min^(-1))and extremely low leaching of Mn(Mnloss%=0.27%).Simultaneously,the synergetic effect of adsorption and degradation on the superior removal of MeB is *** excellent recycling performances,especially the satisfactory removal of MeB from the actual water bodies(e.g.,tap water and river water),as well as potential applications for degradation of RhB and MB enable the MSO-12 microspheres as a novel promising competitive candidate Fenton-like catalyst.

关键词： hierarchical porous manganese silicate microspheres Fenton-like catalysts degradation organic dyes

Precise location of proton of beta-secretase for catalytic aspartates(Asp 32 and Asp 228)in Alzheimer’s patients

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Neural Regeneration Research 2010年第8期5卷 572-578页

作者： Shu Liu Huaqiao wang lihua Zhou Zhibin Yao Department of Anatomy and Brain Research Zhongshan School of Medicine Sun Yat-sen University Guangzhou 510080 GuangdongProvince China

BACKGROUND：β-secretase （β-site APP cleavage rate-limiting enzyme, BACE） has been proposed as a promising therapeutic target for Alzheimer＇s disease （AD）. BACE inhibition reduces production of β-amyloid peptide （Aβ） and promotes neural regeneration. Two catalytic aspartates （Asp 32 and Asp 228） exist in a monoprotonated state in the active BACE site, but the precise proton location remains ***：To explore the entire process of BACE enzymatic hydrolysis using quantum chemistry calculations, and to identify the precise proton location for Asp 32 and Asp 228 during the enzymatic ***, TIME AND SETTING：According to protonation state of BACE, four tautomers were designed and quantum chemistry calculations were performed at the Department of Human Anatomy, Zhongshan School of Medicine, Sun Yat-sen University, China between October 2008 and March ***：Hardware：linux workstation （Department of Equipment, Sun Yat-sen University, China）; software：QSITE, Glide, Maestro （Schrodinger LLC, USA）, MOPAC 2007 （CAChe Research LLC, USA）, Triton 4.0 （National Centre for Biomolecular Research, Czech Republic） were ***：Using crystal structures of BACE to build a catalytic model （enzyme, catalytic water, and substrate peptide EVNLAAEF） on the computer and superimposition, four BACE tautomers （32i, 320, 228i, and 2280） in the monoprotonated state were developed with Schrodinger package. Hybrid quantum mechanical/molecular mechanic （QM/MM） calculations were performed at the B3LYP density functional theory level to identify the precise proton location for the dyad aspartic residues （Asp 32 and Asp 228）. Using the most possible tautomer as the reactant, the entire enzymatic hydrolysis of substrate EVNL/AAEF was simulated at the semiempirical *** OUTCOME MEASURES：The precise proton location of was measured by analyzing co-planarities of 4 BACE tautorners （32i, 32o, 228i, and 2280） in the monoprotonated state, because the dihedral formed by the ca

关键词： Alzheimer's disease β-secretase QM/MM enzymatic hydrolysis quantum chemistry calculation digital medicine neurodegenerative diseases neural regeneration

Dynamics Modeling and Stability Analysis of Tilt Wing Unmanned Aerial Vehicle During Transition

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Computers, Materials & Continua 2019年第6期59卷 833-851页

作者： Yonghong Zhang Yunfei Deng Yunping Liu lihua wang School of information and control Nanjing University of Information Science and TechnologyNanjing210044China

In the transition mode of quad tilt wing-unmanned aerial vehicle(QTW-UAV),the system stability of UAV will change with the tilt angle changes,which will cause serious head drop ***,with the complex air flow and other disturbances,the system is prone to side bias,frying,stall and other kinetic stability problems,hence the system stability analysis has become an urgent problem to be *** solve the stability problem,we need the quantitative criteria of system stability and effective tool of stability analysis,and can improve the stability of the motion control by optimizing the structural parameters of the ***,based on the design of the mechanical structure,the quantitative relationship between the structure parameters of the aerial vehicle and kinetic stability of the system transition mode is established by the Lyapunov exponent *** this paper,the dynamic modeling of the position and attitude angle is carried out and the stability of the system is analyzed by Lyapunov exponent,the results show that changing the mechanical structure of the system can improve the flight stability for the system transition mode and lay a theoretical foundation for the system stability *** with the Lyapunov direct method,this method can be construct easily,has a simple calculation process and so *** improve the flight stability by optimizing the structure and the experiment confirms that expanding area can enhance flight stability within limits.

关键词： QTW-UAV transition stability dynamics model lyapunov exponent

Compressive Sensing Sparse Sampling Method for Composite Material Based on Principal Component Analysis

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Transactions of Nanjing University of Aeronautics and Astronautics 2018年第2期35卷 282-289页

作者： Sun Yajie Gu Feihong Ji Sai wang lihua Jiangsu Engineering Centre of Network Monitoring Nanjing University of Information Science and Technology Nanjing 210044 P. R. China Jiangsu Collaborative Innovation Center on Atmospheric Environment and Equipment Technology Nanjing University of Information Science and Technology Nanjing 210044 P. R. China School of Computer and Software Nanjing University of Information Science and Technology Nanjing 210044 P. R. China School of Information and Control Nanjing University of Information Science and Technology Nanjing 210014 P. R. China

Signals can be sampled by compressive sensing theory with a much less rate than those by traditional Nyquist sampling theorem,and reconstructed with high probability,only when signals are sparse in the time domain or a transform *** signals are not sparse in real world,but can be expressed in sparse form by some kind of sparse *** used sparse transformations will lose some information,because their transform bases are generally *** this paper,we use principal component analysis for data reduction,and select new variable with low dimension and linearly correlated to the original variable,instead of the original variable with high dimension,thus the useful data of the original signals can be included in the sparse signals after dimensionality reduction with maximize ***,the loss of data can be reduced as much as possible,and the efficiency of signal reconstruction can be ***,the composite material plate is used for the experimental *** experimental result shows that the sparse representation of signals based on principal component analysis can reduce signal distortion and improve signal reconstruction efficiency.

关键词： principal component analysis compressive sensing sparse representation signal reconstruction