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Chinese Journal of Polymer Science 2014年第2期32卷 169-176页

作者： wei-li zheng wei-li Hu 陈仕艳 Yi zheng Bi-hui Zhou 王华平 Key Laboratory of High Performance Fibers and Products of Ministry of Education State Key Laboratory for Modification of Chemical Fibers and Polymer Materials College of Materials Science and Engineering Donghua University

The freshly prepared water-wet amidoximated bacterial cellulose （Am-BC） serves as an effective nanoreactor to synthesis zinc oxide nanoparticles by in situ polyol method. The obtained ZnO/Am-BC nanocomposites have been characterized by field emission scanning electron microscopy （FE-SEM）, X-ray diffraction （XRD）, Fourier transformed infrared spectroscopy （FTIR） and thermogravimetric analysis （TGA）. The influence of the zinc acetate concentration on the morphologies and size ofZnO nanoparticles and the possible formation mechanism were discussed. The results indicated that uniform ZnO nanoparticles were homogeneously anchored on the Am-BC nanofibers through strong interaction between the hydroxyl and amino groups of Am-BC and ZnO nanoparticles. The loading content of ZnO nanoparticles is higher using Am-BC as a template than using the unmodified bacterial cellulose. The resultant nanocomposite synthesized at 0.05 wt% shows a high photocatalytic activity （92%） in the degradation of methyl orange.

关键词： Amidoximated bacterial cellulose Nanoreactor ZnO nanoparticles High photocatalytic activity.

Collapse analysis of tunnel floor in karst area based on Hoek-Brown rock media

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Journal of Central South University 2017年第4期24卷 957-966页

作者： YANG Xiao-li li zheng-wei liU zheng-an XIAO Hai-bo School of Civil Engineering Central South University Changsha 410075 China

Collapse shape of tunnel floor in Hoek-Brown rock media is investigated with the functional catastrophe theory. The stability of rock system in tunnel floor, which is determined by thickness, half collapse width, half length of cave and detaching curve, has great secure and economic significance in practical engineering. To investigate the failure mechanisms and the outline of detaching block, a reliable damage model is presumed by making reference to the limit analysis theory. The analytical solutions of detaching curve, half collapse width on tunnel floor and the critical and maximum values of collapse thickness are derived based on Hoek-Brown criterion and functional catastrophe theory. The result shows that 0.5 is a most probable condition for instability, and the shape of detaching curve is a part of parabola. It is reasonable by comparing with previous theory and analogous experiments. The effects of major factors on thickness and half collapse width are further discussed. Numerical calculations and parametric analysis are carried out to illustrate the effects of different parameters on the mechanism, which is significant to the stability analysis of tunnel floor in rock media.

关键词： karst functional catastrophe theory Hoek-Brown criterion safety thickness tunnel floor upper bound

Structure,optical,and magnetic properties of Mn-doped ZnO films prepared by sputtering

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International Journal of Minerals,Metallurgy and Materials 2010年第4期17卷 475-480页

作者： li-wei Wang zheng Xu Fu-junZhang Su-ling Zhao li-fang Lu Institute of Optoelectronics Technology Key Laboratory of Luminescence and Optical Information （Ministry of Education of China） Beijing Jiaotong University Beijing100044 China

The microstructural, optical, and magnetic properties and room-temperature photoluminescence （PL） ofMn-doped ZnO thin films were studied. The chemical compositions were examined by energy dispersive X-ray spectroscopy （EDS） and the charge state of Mn ions in the ZnO：Mn films was characterized by X-ray photoelectronic spectrometry （XPS）. From the X-ray diffraction （XRD） data of the samples, it can be found that Mn doping does not change the orientation of ZnO thin films. All the films prepared have a wurtzite structure and grow mainly along the c-axis orientation. The grain size and the residual stress were calculated from the XRD results. The optical transmittance of the film decreases with the increase of manganese content in ZnO. The room-temperature photoluminescence of the films shows that the in- tensity of near band energy （NBE） emission depends strongly on the Mn content. The hysteresis behavior indicates that the films with the Mn content below 9at% are ferromagnetic at room temperature.

关键词： ZnO magnetron sputtering ferromagnetism optical properties photoluminescence

Bovine Serum Albumin Loaded Solid lipid Nanoparticles Prepared by Double Emulsion Method

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Chemical Research in Chinese Universities 2010年第1期26卷 136-141页

作者： li Zhen li Xin-wei zheng li-qiang liN Xiao-hong GENG Fei YU li Key Laboratory of Colloid and Interface Chemistry Ministry of Education Shandong University Jinan 250100 P. R. China

Solid lipid nanoparticles loaded with bovine serum albumin（BSA） were prepared by a double emulsion method. As the mass fraction of the model drug BSA increased from 0 to 15%, the particle size gradually increased. The physical stability of the nanoparticles was investigated by zeta potential measurement and they were shown to be quite stable. Fluorescence spectroscopy confirmed that the loaded position of BSA was on the interface between the inner aqueous phase and the solid lipid phase. Both Fourier-transform infrared spectroscopy and circular dichroism spectra indicate that BSA in the nanoparticles was not destroyed, but the secondary structure was disrupted slightly.

关键词： Solid lipid nanoparticle Double emulsion Bovine serum albumin Drug model

Noise character analysis and the restraint of self-pulsation laser diodes

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Optoelectronics Letters 2008年第3期4卷 168-171页

作者： JIANG Ning PAN wei LUO Bin ZHANG wei-li zheng Di Institute of Optical Communication and Optical Devices South West Jiaotong University Chengdu 610031 China

We calculate the Langevin noise sources of self-pulsation laser diodes,analyze the effects of active region noise and saturable-absorption region noise on the power fluctuation as well as period fluctuation,and propose a novel method to restrain the noise effects. A visible SIMUliNK model is established to simulate the system,the results indicate that the effects of noise in absorption region can be ignored;that with the increase of DC injecting current,the noise effects enhance power jitter,and nevertheless,the period jitter is decreased;and that with external sinusoidal current modulating the self-pulsation laser diode,the noise-induced power jitter and period jitter can be suppressed greatly. This work is valuable for clock recovery in all-optical network.

关键词：噪音分析分析方法激光二极管预防措施

Facile fabrication of Fe/Zr binary MOFs for arsenic removal in water:High capacity,fast kinetics and good reusability

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Journal of Environmental Sciences 2023年第6期128卷 213-223页

作者： Qi Guo Yuan li li-wei zheng Xiao-Yangwei Yan Xu Yi-Wen Shen Ke-Gang Zhang Chun-Gang Yuan Hebei Key Lab of Power Plant Flue Gas Multi-Pollutants Control Department of Environmental Science&EngineeringNorth China Electric Power UniversityBaoding 071000China Wetland Research Center for Baiyangdian Lake North China Electric Power UniversityBaoding 071000China

A water-stable bimetallic Fe/Zrmetal-organic framework[UiO-66(Fe/Zr)]for exceptional decontamination of arsenic in water was fabricated through a facile one-step *** batch adsorption experiments revealed the excellent performances with ultrafast adsorption kinetics due to the synergistic effects of two functional centers and large surface area(498.33 m^(2)/g).The absorption capacity of UiO-66(Fe/Zr)for arsenate[As(V)]and arsenite[As(III)]reached as high as 204.1 mg/g and 101.7 mg/g,*** model was suitable to describe the adsorption behaviors of arsenic on UiO-66(Fe/Zr).The fast kinetics(adsorption equilibrium in 30min,10mg/L As)and pseudo-second-ordermodel implied the strong chemisorption between arsenic ions and UiO-66(Fe/Zr),which was further confirmed by DFT theoretical *** results of FT-IR,XPS analysis and TCLP test demonstrated that arsenic was immobilized on the surface of UiO-66(Fe/Zr)through Fe/Zr-O-As bonds,and the leaching rates of the adsorbed As(III)and As(V)from the spent adsorbent were only 5.6%and 1.4%,***-66(Fe/Zr)can be regenerated for five cycles without obvious removal efficiency *** original arsenic(1.0mg/L)in lake and tapwater was effectively removed in 2.0 hr[99.0%of As(III)and 99.8%of As(V)].The bimetallic UiO-66(Fe/Zr)has great potentials in water deep purification of arsenic with fast kinetics and high capacity.

关键词： Arsenic Removal Metal-organic frameworks Bimetallic

Isothermal compression behavior and constitutive modeling of Ti-5Al-5Mo-5V-1Cr-1Fe alloy

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Transactions of Nonferrous Metals Society of China 2018年第6期28卷 1114-1122页

作者： li-li CHANG li-wei zheng School of Materials Science and Engineering Shandong UniversityJi＇nan 250061China

Hot compression behavior of Ti-5 Al-5 Mo-5 V-1 Cr-1 Fe alloy with an equiaxed（α＋β） starting microstructure was investigated by isothermal compression test and optical microscopy. Based on the true strain-stress data with temperature correction, constitutive models with a high accuracy were developed and processing maps were established. Strain inhomogeneity at different locations in the compressed sample is reduced by raising temperature, leading to a uniform distribution of α phases. For the temperature range of 800-840 ℃ with a strain rate of 10 s^-1, the transformed volume fraction of α phase increases and the average grain size of α phase decreases slightly with increasing the temperature, indicating co-existence of dynamic recovery and dynamic recrystallization. Flow localization and faint β grain boundaries are observed at the strain rate of 10 s^-1 in the temperature range of 860-900 ℃. The processing map analysis shows that hot working of Ti-5 Al-5 Mo-5 V-1 Cr-1 Fe alloy should be conducted with the strain rate lower than 0.01 s^-1 to extend its workability.

关键词： Ti-5Al-5Mo-5V-1Cr-IFe alloy isothermal compression constitutive equations processing map

Raman Frequency Conversion of Picosecond Pulses in the YVO4 Crystal

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Chinese Physics Letters 2013年第8期30卷 66-69页

作者： XU Yang CHEN Meng li zheng-wei BAI Zhen-Xu YANG Chao CHEN li-Yuan li Gang liU Yang Institute of Laser Engineering Beijing University of TechnologyBeijing 100124 The Northern Institute of Electronic Equipment of China No.1 HuanyuanHaidian DistrictBeijing 100083

We compare the stimulated Raman scattering(SRS)performance of a-cut and c-cut YVO4 in a single-pass Raman *** undoped YVO4 crystal shows its good SRS capability in a quasi-transient *** non-axial scattering angles of Raman radiation are also studied,and the result is in good agreement with the physical model based on the phase matching ***-order Raman Stokes and anti-Stokes lights with good beam quality are obtained by means of Raman *** experiments show that Raman amplification is a practical way to avoid unexpected nonlinear effects and to obtain new wavelength picosecond lasers.

关键词： scattering Crystal Stokes

Metabolic-epigenetic nexus in regulation of stem cell fate

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World Journal of Stem Cells 2022年第7期14卷 490-502页

作者： Yi liu Di-Xin Cui Yue Pan Si-Han Yu li-wei zheng Mian Wan State Key Laboratory of Oral Diseases National Clinical Research Center for Oral DiseasesDepartment of Pediatric DentistryWest China Hospital of StomatologySichuan UniversityChengdu 610041Sichuan ProvinceChina State Key Laboratory of Oral Diseases National Clinical Research Center for Oral DiseasesDepartment of Cariology and EndodonticsWest China Hospital of StomatologySichuan UniversityChengdu 610041Sichuan ProvinceChina

Stem cell fate determination is one of the central questions in stem cell biology,and although its regulation has been studied at genomic and proteomic levels,a variety of biological activities in cells occur at the metabolic *** studies have established the metabolome during stem cell differentiation and have revealed the role of metabolites in stem cell fate *** metabolism is considered to play a biological regulatory role as an energy source,recent studies have suggested the nexus between metabolism and epigenetics because several metabolites function as cofactors and substrates in epigenetic mechanisms,including histone modification,DNA methylation,and ***,the epigenetic modification is sensitive to the dynamic metabolites and consequently leads to changes in *** nexus between metabolism and epigenetics proposes a novel stem cell-based therapeutic strategy through manipulating *** the present review,we summarize the possible nexus between metabolic and epigenetic regulation in stem cell fate determination,and discuss the potential preventive and therapeutic strategies via targeting metabolites.

关键词： Metabolism Epigenetic regulation Stem cell fate Nexus effect

Effect of acupressure on sleep quality of middle-aged and elderly patients with hypertension

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International Journal of Nursing Sciences 2014年第4期1卷 334-338页

作者： li-wei zheng Yao Chen Feng Chen Ping Zhang li-Fang Wu Fujian University of Traditional Chinese Medicine FuzhouChina Department of Cardiology Fujian General HospitalFuzhouChina

Purpose:To evaluate the effect of acupressure on blood pressure and sleep quality in middle-aged and elderly patients with ***:A total of 75 elderly hypertensive patients with sleep disorders were randomly divided into either an experimental group(n=38)or a control group(n=37).All subjects received conventional treatment and health *** experimental group also received acupressure *** score of PSQI(Pittsburgh Sleep Quality Index)and blood pressure were measured and recorded before and after the ***:After the intervention,the systolic(SBP)and diastolic blood pressure of the experimental group decreased significantly(plity in middleaged and elderly patients with hypertension.

关键词： Acupressure Hypertension Sleep quality