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RNAi,a new therapeutic strategy against viral infection

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Cell Research 2004年第6期14卷 460-466页

作者： Fischer l.TAN,James q.YIN Institute of Biophysics Institute of Biophysics Chinese Academy of Sciences 15 Datun Road Beijing 100101 China. Chinese Academy of Sciences 15 Datun Road Beijing 100101 China.

RNA interference (RNAi) is an adaptive defense mechanism triggered by double-stranded RNA (dsRNA). It is a powerful reverse genetic tool that has been widely employed to silence gene expression in mammalian and human cells. RNAi-based gene therapies, especially in viral diseases have become more and more interesting and promising. Recently, small interfering RNA (siRNA) can be used to protect host from viral infection, inhibit the expression of viral antigen and accessory genes, control the transcription and replication of viral genome, hinder the assembly of viral particles, and display influences in virus-host interactions. In this review, we attempt to present recent progresses of this breakthrough technology in the above fields and summarize the possibilities of siRNA-based drugs.

关键词： RNAi siRNA viral infection gene therapy.

A brief review：experimental investigation of zonal flows and geodesic acoustic modes in fusion plasmas

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Plasma Science and Technology 2018年第9期20卷 72-84页

作者： K J ZHAO J q DONG J q lI l W YAN Southwestern Institution of Physics Chengdu 610041People＇s Republic of China

Zonal flows self-generated by turbulence play an important role in regulating turbulence,reducing transport level,and thus improve plasma confinement in fusion *** zonal flows and geodesic acoustic modes have been identified in various *** related issues,such as the poloidal and toroidal symmetries,coupling to turbulence,effects on turbulence and transport,nonlinear energy transfer between turbulence and zonal flows,dependence of the plasma parameters,roles in the confinement regime transitions etc are overviewed briefly in this *** interaction between zonal flows and magnetic islands is emphasized.

关键词： zona flow tokamak turbulence fusion plasma

Spalling characteristics of high-temperature treated granitic rock at different strain rates

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Journal of Rock Mechanics and Geotechnical Engineering 2024年第4期16卷 1280-1288页

作者： l.F.Fan q.H.Yang X.l.Du The Key laboratory of Urban Security and Disaster Engineering of Ministry of Education Beijing University of TechnologyBeijing100124China

The dynamic spalling characteristics of rock are important for stability analysis in rock *** paper presented an experimental investigation on the dynamic spalling characteristics of granite with different temperatures and strain rates.A series of dynamic spalling tests with different impact velocities were conducted on thermally treated granite at different *** dynamic spalling strengths of granite with different temperatures and strain rates were determined.A model was proposed to correlate the dynamic spalling strength of granite,high temperature and strain *** results show that the spalling strength of granite decreases with increasing ***,the spalling strength of granite with a higher strain rate is larger than that with a lower strain *** proposed model can describe the relationship among dynamic spalling strength of granite,high temperature and strain rate.

关键词： Dynamic spalling characteristics High temperature Strain rate Dynamic loading Granite

STUDY OF RAY IRRADIATION ON DIAMOND-lIKE CARBON FIlMS

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Acta Metallurgica Sinica(English letters) 2002年第1期15卷 26-32页

作者： G.A. liu T.M. wang E.q Department of Applied Physics Southwest Jiao Tong University Chengdu 610031 China Beijing University of Aeronautics and Astronautics Beijing 100083 China Department of Physics Lanzhou University Lanzhou 730000 China

Diamond-like carbon (DlC) films have been deposited on glass substrates usingradio-frequency (rf) plasma deposition method. Gamma -ray, ultraviolet (UV) ray were used toirradiate the DlC films. Raman spectroscopy and infrared (IR) spectroscopy were use to characterizethe changing characteristics of SP^3 C-H bond and hydrogen content in the films due to theirradiations. The results show that, the damage degrees induced by the UV ray on the SP^3 C-H bondsare much stronger than that by the gamma -ray. When the irradiation dose of gamma -ray reaches 1 OX10^4 Gy, the SP^3 C-H bond reduces about 50 percent in number. The square electrical resistance ofthe films is reduced due to the irradiation of UV ray and this is caused by severe oxidation of thefilms. By using the results on optical gap of the films and the fully constrained network theory,the hydrogen content in the as-deposited films is estimated to be l0-25at. percent.

关键词： diamond-like carbon film gamma -ray irradiation ultraviolet rayirradiation SP^3 C-H bond infrared transmittance

Deformation behaviors of as-built and hot isostatically pressed Ti-6Al-4V alloys fabricated via electron beam rapid manufacturing

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Journal of Materials Science & Technology 2019年第11期35卷 2552-2558页

作者： Z.liu Z.B.Zhao J.R.liu l.wang S.X.Zhu G.Yang S.l Gong q.J.wang R.Yang institute of metal research chinese academy of sciencesshenyang110016china school of materials science and engineering university of science and technology of chinahefei230000china avic manufacturing technology institute beijing100024china

The deformation behavior of as-built and hot isostatically pressed(HIP)Ti-6Al-4V alloys fabricated using electron beam rapid manufacturing(EBRM)were investigated in this *** deformation characteristics were characterized using a laser scanning confocal microscope and electron back-scattered diffraction(EBSD).In the as-built sample,prismatic slip was the main mode of deformation,as well as a small amount of basal slip and *** planar slip lines with large length scales were observed across severalα*** hot isostatical pressing,prismatic and basal slip were the main mode of deformation,accompanied by abundant cross-slip and multiple slip,and most of the slip lines were blocked within an a *** differences in deformation behavior were associated with the coarsening of a laths and the more retained p phase after HIP compared to the as-built *** cross-slip and multiple slip can lead to superior elongation-to-failure and a greater strain hardening effect in the HIP alloy compared to the as-built sample.

关键词： Electron beam rapid manufacturing Ti-6Al-4V Hot isostatic pressure Mechanical properties Slip behavior

Finite Element Prediction of the Thermal Conductivity of GNP/Al Composites

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Acta Metallurgica Sinica(English letters) 2022年第5期35卷 825-838页

作者： X.S.Yang l.Zhou K.Y.liu Z.Y.liu q.Z.wang B.l.Xiao Z.Y.Ma School of Electromechanical and Automotive Engineering Yantai UniversityYantai264005China Shi-Changxu Innovation Center for Advanced Materials Institute of Metal ResearchChinese Academy of SciencesShenyang110016China

A 3 D multi-scale finite element model was developed to predict the effective thermal conductivity of graphene nanoplatelet(GNP)/Al *** factors influencing the effective thermal conductivity of the GNP/Al composites were investigated,including the orientation,shape,aspect ratio,configuration and volume fraction of *** results show that GNPs shape has a little influence on the thermal conductivity of GNP/Al composites,and composites with elliptic GNPs have the highest thermal *** addition,with increasing the aspect ratio of GNPs,the thermal conductivity of GNP/Al composites increases and finally tends to be *** GNPs configuration strongly influences the thermal conductivity of GNP/Al composites,and the thermal conductivity of the composites with layered GNPs is the highest among the five *** effective thermal conductivity is sensitive to volume fraction of ***,when the volume fraction of layered GNPs reaches 1.54%,the thermal conductivity of GNP/Al composites is as high as 400 W/m *** findings of this study could provide a good theoretical basis for designing high thermal conductivity GNP/Al composites.

关键词： Multi-scale finite element model Thermal conductivity GNP/Al composites Shape Aspect ratio Configuration

Current diffusion and efficiency droop in vertical light emitting diodes

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Chinese Physics B 2019年第1期28卷 561-569页

作者： R q Wan T li Z q liu X Y Yi J X wang J H li W H Zhu J M li l C wang State Key laboratory of High Performance Complex Manufacturing College of Mechanical and Electrical EngineeringCentral South University Semiconductor lighting Technology Research and Development Center Institute of SemiconductorsChinese Academy of Sciences College of Materials Science and Opto-Electronic Technology University of Chinese Academy of Sciences

Current diffusion is an old issue, nevertheless, the relationship between the current diffusion and the efficiency of light emitting diodes(lEDs) needs to be further quantitatively clarified. By incorporating current crowding effect(CCE) into the conventional ABC model, we have theoretically and directly correlated the current diffusion and the internal quantum efficiency(IqE), light extraction efficiency(lEE), and external quantum efficiency(EqE) droop of the lateral ***, questions still exist for the vertical lEDs(V-lEDs). Here firstly the current diffusion length l_s(I) and l_s(II) have been clarified. Based on this, the influence of CCE on the EqE, IqE, and lEE of V-lEDs were investigated. Specifically to our V-lEDs with moderate series resistivity, l_s(III) was developed by combining l_s(I) and l_s(II), and the CCE effect on the performance of V-lEDs was investigated. The wall-plug efficiency(WPE) of V-lEDs ware investigated finally. Our works provide a deep understanding of the current diffusion status and the correlated efficiency droop in V-lEDs, thus would benefit the V-lEDs' chip design and further efficiency improvement.

关键词： efficiency droop vertical light emitting diodes current crowding effect current blocking layer

EFFECT OF ANNEAlING TREATMENT ON THE STRUCTURE OF CdS FIlMS

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Acta Metallurgica Sinica(English letters) 2003年第4期16卷 313-318页

作者： G.B.liu W.l.wang C.G.Hu K.J.liao q.Feng l.H.Feng DepartmentofAppliedPhysics ChongqingUniversityChongqing400044China OptoelectronTechnologyandSystemlaboratoryofEducationMinistry ChongqingUniversityChongqing400044ChinaManuscriptreceived25November2002 DepartmentofMaterialScience SichuanUniversityChengdu610064China

The effect of annealing treatment on the structure of CdS films was investigated. The cadmium sulfide thin films were prepared by chemical bath deposition, and were annealed at nitrogen atmosphere at different temperatures. The films were characterized by SEM and XPS (X-ray photoelectron spectroscopy). X-ray photoelectron spectroscopy was used to examine the chemical states on the CdS films surface. It was found that thermal annealing could produce large grains of CdS thin films, remove the air contamination and reduce the oxygen content on the CdS films surface. Therefore, the CdS films changed more uniform and smoother surface after thermal annealing.

关键词： XPS CdS thin film CBD (chemical bath deposition)

OPTICAl CHARACTERIZATION OF TiO_2 THIN FIlM ON SIlICON SUBSTRATE DEPOSITED BY DC REACTIVE MAGNETRON SPUTTERING

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Acta Metallurgica Sinica(English letters) 2005年第3期18卷 194-198页

作者： H.q.wang H.Shen D.C.Ba B.W.wang l.S.Wen D.Chen SchoolofMechanismandAutomobile ShenyangInstituteofAeronauticalEngineeringShenyang110034Ghina／／MechanismandAeronauticalCollegeNortheasternUniversityShenyang110004China TheSchoolofPhysicsandEngineering ZhongshanUniversityGuangzhou510275Ghina MechanismandAeronauticalCollege NortheasternUniversityShenyang110004China GuangzhouInstimdeofEnergyConversion Guangzhou510070China InstituteofMetalResearch TheChineseAcademyofSciencesShenyang110016China MaterialandScienceEngineeringAcademy SouthChinaUniversityofTechnologyGuangzhou510641China

TiO2 thin film has attracted considerable attention in recent years, due to its different refractive index and transparency with amorphous and different crysta ls in the visible and near-infrared wavelength region, high dielectric constant, wide band gap, high wear resistance and stability, etc, for which make it being used in many fields. This paper aims to investigate the optical characterizatio n of thin film TiO2 on silicon wafer. The TiO2 thin films were prepared by DC re active magnetron sputtering process from Ti target. The reflectivity of the film s was measured by UV-3101PC, and the index of refraction (n) and extinction coef ficient (k) were measured by n & k Analyzer 1200.

关键词： optical characterization TiO2 thin film DC reactive magnetron sputtering n & k