Synthesis,Characterization and Biocompatibility of Potassium Ferrite Nanoparticles简

In the present study,morphology,size distribution,structure,biocompatibility and magnetic properties of potassium ferrite nanoparticles(KFeO_2 NPs),synthesized by conventional sol—gel method have been reported.The formation of spherical nanoparticles with orthorhombic structure has been confirmed by scanning electron microscopy and X-ray diffraction.The particle size,as obtained by transmission electron microscopy has been found to be in the range of 4—7 nm.Further,the size distribution has been scrutinized using Analyse-it software,where a platykurtic feature in the size distribution was observed.Fourier transform-infrared spectroscopy and thermogravimetric analysis showed the formation of metal(Fe,K) bonds at Neel temperature of 337℃.Vibrating sample magnetometer analysis revealed the superparamagnetic behaviour of the synthesized KFeO_2NPs,with saturation magnetization of 25.72 emu/g.In vitro cytotoxicity test,using MTT assay,on T cell lines(Jurkat cells) showed that KFeO_2 NPs are biocompatible at a particle concentration of 100 |j.g/ml.     

Plasmon-enhanced Performance of Dye-sensitized Solar Cells Based on Electrodeposited Ag Nanoparticles简

In the present work,pulse current deposition is used to deposit evenly distributed and uniformly sized Ag nanoparticles onto a TiO_2 nanotube array as photoelectrode in dye-sensitized solar cells(DSSCs),and the size and amount of loading Ag nanoparticles are controlled by the pulse deposition time.Due to the enhanced light absorption and electron—hole separation caused by plasmon effect,DSSCs based on Ag-modified TiO_2nanotube arrays show higher energy conversion efficiencies than those based on bare nanotubes with the same tube length.Particularly,DSSC based on nanotubes modified using pulse deposition time 1 s/3 s delivers the highest energy conversion efficiency of 1.68%and the largest short-circuit current of 4.37 mA/cm~2,while DSSC consisting of bare nanotubes exhibits efficiency of 1.20%and short-circuit current of2.27 mA/cm~2,which represents a 40%enhancement of cell efficiency in DSSC based on Ag-modified TiO_2nanotubes.It is also noted that overly long pulse deposition time will not further increase DSSC efficiency due to agglomeration of Ag particles.For example,when the pulse deposition time is increased to 2 s/6 s,DSSC based on Ag-modified nanotubes exhibits a lower efficiency of 1.42%.Moreover,high-concentration TiCl_4treatment on TiO_2 nanotube arrays can further increase the energy conversion efficiencies to 3.82%and2.61%for DSSC based on Ag-modified TiO_2 nanotubes and DSSC based on bare TiO_2 nanotubes,respectively,by significantly creating more surface area for dye loading.     

全球石墨烯技术领域专利计量分析简

石墨烯（Graphene）是一种由碳原子构成的单层片状结构的新材料，是由碳原子以sp^2杂化轨道组成六角型呈蜂巢晶格的平面薄膜。石墨烯目前是世上最薄却最坚硬的纳米材料，具有良好的电子运输、导电导热及机械特性，可广泛应用于纳米器件、传感器、基因检测等领域。     

Quaternary Ammonium-based Composite Particles for Antibacterial Finishing of Cotton-based Textiles简

The antibacterial finishing of cotton-based fabrics has been achieved from quaternary ammonium-based composite particles. This functionalization is based on the simple dilution of a quaternary ammonium cation （QAC） hybrid alkoxide within a sol-gel derived crystalline suspension （CS） of TiO2 in liquid solution. This protocol yields the preparation of QAC-Ti02 （QT） composite sols by using a same CS over a long period of time, and enables an easy regeneration of derived QT sols after quite long aging periods. Composite sols can then be impregnated on various kinds of substrates, including textile fabrics. Fourier transform infrared spectroscopy studies, as well as optical and scanning electron microscopy observations, have been used to investigate chemical and morphological features arising from QT particles. Antibacterial tests have then been performed on so-finished textiles and are discussed in relation to chemical and morphological features. It is shown that this sol-gel route flexibly yields a similarly strong antibacterial activity on cotton-based fabrics against both Gram-negative and Gram-positive bacteria, Le. tested fabrics exhibit an antibacterial activity （a（~cording to the ISO 20743-2005 standard） ranging between 7.5 and 7.9 against both kinds of bacteria tested here. Finishing treatments also allow preserving the hand feeling and visual aspect of the textiles and promote a rather good attachment of impregnated particles on the surface of textile fibers.     

Simultaneously Enhanced Cryogenic Tensile Strength,Ductility and Impact Resistance of Epoxy Resins by Polyethylene Glycol简

Rubbers have been well accepted for modifying brittle epoxies but rubber modified epoxies usually posses lowered tensile strength though enhanced ductility and fracture resistance. In this work, a polyethylene glycol （PEG-4000） is used to modify diglycidyl ether of bisphenol A/methyltetrahydrophthalic anhydride system for enhancing cryogenic tensile strength, ductility and impact resistance. The results display that the cryogenic tensile strength, ductility （failure strain） and fracture resistance （impact strength） are all enhanced for the modified epoxy system at proper PEG contents. The maximum tensile strength （127.8 MPa） at the cryogenic temperature （77 K） with an improvement of 30.1% is observed for the modified system with the 15 wt% PEG content. The ductility and impact resistance at both room temperature and cryogenic temperature are all improved for the modified epoxy system with proper PEG-4000 contents. These observations are explained by the positron annihilation lifetime spectroscopy results and scanning electron microscopy results. Moreover, the glass transition temperature decreases slightly with increasing PEG content.     

Fabrication of Shape-Controlled Au Nanoparticles in a TiO2-Containing Mesoporous Template Using UV Irradiation and Their Shape-Dependent Photocatalysis简

A SiO_2-TiO_2 template with ordered tubular mesochannels has been prepared by the sol—gel method.Au nanorods are deposited in the tubular mesochannels of the SiO_2—TiO_2 template,and the shape of Au is changed from nanorods to nanospheres by ultraviolet irradiation during thermal deposition.The photocatalytic activity of mesoporous SiO_2—TiO_2 with/without Au nanorods/nanospheres is evaluated.Deposition of Au in the mesoporous SiO_2—TiO_2 template enhances the photocatalysis of TiO_2.Interestingly,the sample containing Au nanorods exhibits higher photocatalytic activity than that with Au nanospheres.Photocatalysis by exciting surface plasmon resonance is not detected in the composite samples regardless of the shape of the deposited Au nanoparticles.     

Effect of Sm+ Rare Earth Ion on the Structural,Thermal,Mechanical and Optical Properties of Potassium Hydrogen Phthalate Single Crystals简

Rare earth Sm~+ ion doped potassium hydrogen phthalate(KHP) single crystal was grown by slow evaporation technique.Single crystal and powder X-ray diffraction analyses confirm the crystalline perfection of Sm~+ ion doped KHP crystal.The functional groups of pure and Sm~+ ion doped KHP crystals were identified by Fourier transform infrared spectroscopy(FTIR) spectral studies.Thermogravimetric and differential thermal analyses were carried out to study the thermal behavior of the grown crystals.UV—Vis studies explored the optical transmittance of the grown crystals in the entire visible region.The mechanical strength and etching studies were performed to assess the perfection of the pure and Sm~+ ion doped KHP crystals.The refractive index and birefringence properties of the grown crystal were analyzed.The second harmonic generation efficiency of Sm~+ ion doped KHP crystals was observed by Kurtz—Perry powder test.     

Effect of Hydrodynamic Conditions on Corrosion Inhibition of Cu-Ni (90/10) Alloy in Seawater and Sulphide Containing Seawater Using 1,2,3-Benzotriazole简

Electrochemical studies of the effect of hydrodynamic conditions on corrosion inhibition of Cu—Ni(90/10) alloy in synthetic seawater and sulphide containing synthetic seawater by 1,2,3-benzotriazole(BTAH) are presented.Impedance,potentiodynamic polarization and cyclic voltammetric(CV) studies are employed in the present investigation.The studies are carried out by using Cu—Ni(90/10) alloy rotating disc electrode at different rotation speeds and at different immersion periods.Reynolds numbers at each rotation speed infer that the flow of seawater is laminar.With increasing rotation speed of the electrode immersed in seawater without sulphide and BTAH,both the charge transfer resistance(R_(ct)) and film resistance(R_(film)) are increased.However,in the presence of sulphide ions and without BTAH,both the R_(ct) and R_(film) are found to decrease with increasing rotation speed at identical immersion periods.Interestingly,when BTAH is added to seawater or seawater containing sulphide,both the R_(ct) and R_(film) are increased to such a great extent that an inhibition efficiency of 99.99%is obtained.In the presence of BTAH,the phase angle Bode plots are more broadened and the maximum values of phase angle are increased to a value close to 90° as the rotation speed is increased.The BTAH film is highly protective even under hydrodynamic condition also.Potentiodynamic polarization studies infer that BTAH functions as a mixed inhibitor under hydrodynamic conditions also.CV studies reveal that the protective BTAH film is stable even at anodic potentials of +850 mV vs Ag/AgCI.     

脉冲激光沉积制备SnS薄膜及其光学特性的研究

利用脉冲激光沉积法在玻璃衬底上制备SnS薄膜,研究了SnS薄膜的晶体结构、表面形貌以及有关光学特性。所制备的SnS薄膜样品为斜方晶系多晶结构,在(111)晶面上有很强的择优取向性;衬底温度在100~400℃范围内,表面形貌有所区别,随着温度升高,薄膜表面分别呈现大小晶粒共存、片状颗粒、针状颗粒和锥状颗粒的形貌特征;紫外区的SnS薄膜透过率极低,可见光范围的透过率很低,近红外区的透过率较大;样品在可见区和紫外区吸收强烈,吸收系数达105cm-1量级,直接禁带宽度为1.39~1.46 eV。     

脉冲激光沉积法在Si(111)衬底上生长高c轴取向LiNbO3薄膜

在氧压20Pa,衬底温度600℃,靶材与衬底距离4cm的最优化条件下,利用脉冲激光沉积(PLD)技术首次在无诱导电压和任何缓冲层的情况下,在单晶Si(111)衬底上生长具有优良结晶品质和高c轴取向的LiNbO3晶体薄膜.利用X射线衍射(XRD)、扫描电子显微镜(SEM)和原子力显微镜(AFM)对LiNbO3薄膜的结晶品质,择优取向性以及表面形貌进行了系统的分析.结果表明生长出了具有优异晶体质量的c轴取向LiNbO3薄膜,表面光滑平整且无裂纹产生,表面粗糙度约4.8nm,有利于硅基光电子器件的制备和利用.     

脉冲激光沉积氢化锂薄膜(英文)

用脉冲激光沉积制备了氢化锂薄膜,对薄膜的结构和表面形貌进行了,给出了氢气压和靶基距与沉积速率的关系。运用扫描电镜和X射线衍射仪测试薄膜的性质。测试结果显示,氢气压为10-1mbar时,薄膜表面粗糙且呈现多晶态。对薄膜粗糙度与氢气压的关系进行了讨论。     

脉冲激光沉积ZrW2O8薄膜的制备和性能

采用脉冲激光沉积法在石英基片上沉积制备了ZrW2O8薄膜.用X射线衍射仪(XRD)、原子力显微镜(AFM)研究了不同衬底温度对薄膜结构组分、表面粗糙度和形貌的影响,用台阶仪和分光光度计测量薄膜的厚度和不同衬底温度下制备薄膜的透射曲线,用变温XRD分析了ZrW2O8薄膜的负热膨胀特性.实验结果表明:在衬底温度为室温、550℃和650℃下脉冲激光沉积的ZrW2O8薄膜均为非晶态,非晶膜在1200℃保温3min后淬火得到立方相ZrW2O8薄膜;随着衬底温度的升高,ZrW2O8薄膜的表面粗糙度明显降低;透光率均约为80%,在20～600℃温度区间内,脉冲激光沉积制备的ZrW2O8薄膜的负热膨胀系数为-11.378×10-6 K-1.     

脉冲激光沉积磷掺杂多晶硅薄膜的压阻性能

采用脉冲激光沉积法(PLD)制备磷掺杂多晶硅薄膜,研究磷掺杂分数对多晶硅薄膜压阻性能的影响。结果表明,随着磷掺杂分数增大,多晶硅薄膜的应变系数先增大后减小。在磷掺杂分数为0.3%(质量分数)时,电阻横向应变系数的绝对值达到最大,为24.3,电阻纵向应变系数的绝对值达到最大,为12.6。横向电阻应变的非线性在1%~2.5%之间,电阻的温度系数为0.05%/℃,应变系数的温度系数为-0.06%/℃。     

PLD制备钛酸铅薄膜过程的RHEED分析

本文采用反射式高能电子衍射(RHEED)监测脉冲激光沉积法制备钛酸铅薄膜过程.根据PbTiO3/MgO(001)薄膜、PbTiO3/Si(100)薄膜生长过程中RHEED强度的时间演变,分析基片对薄膜生长模式的影响.并且观测不同生长时刻的RHEED强度的空间分布,讨论生长过程中薄膜表面的台阶尺寸变化.另外,比较在不同氧分压下沉积的钛酸铅薄膜表面的RHEED图案,发现氧气将改变薄膜的微结构,提高薄膜的结晶性.     

硅基氧化铱薄膜的脉冲激光沉积及其微观结构研究

采用脉冲激光沉积技术，在Si（100）基片上制备了高致密的氧化铱（IrO2）薄膜，研究了不同沉积温度对薄膜结构的影响。利用X射线衍射（XRD）、拉曼光谱、扫描电镜（SEM）和原子力显微镜（AFM）对制备的IrO2薄膜进行了表征。结果表明：在20Pa氧分压，250℃～500℃范围内，得到的薄膜为多晶的IrO2物相，其晶粒尺寸和粗糙度随着沉积温度的升高而增加；所得到的IrO2薄膜表面粗糙度低，厚度均匀，与基片结合良好。     

Si(100)衬底上PLD法制备高取向度AlN薄膜

采用脉冲激光沉积法(PLD),以KrF准分子为脉冲激光源,Si(100)为衬底,同时引 入缓冲层TiN和Ti_0.8Al_0.2N,制备了结晶质量优异的A1N薄膜,X射线衍射(XRD)及反射 式高能电子衍射(RHEED)分析表明A1N薄膜呈(001)取向、二维层状生长.研究发现,薄膜 的生长模式依赖于缓冲层种类,直接在Si衬底上或MgO／Si衬底上的A1N薄膜呈三维岛状生 长;而同时引入缓冲层TiN和Ti_0.8Al_0.2N时,A1N薄膜呈二维层状生长.此外,激光能量密 度大小对A1N薄膜的结晶性有显著的影响,激光能量密度过大,薄膜表面粗糙,有颗粒状沉积 物生成.在氮气气氛中沉积,能使薄膜的取向由(001)改变为(100).     

Properties of ZnO Thin Films Grown on Si (100) Substrates by Pulsed Laser Deposition

ZnO thin films were grown on Si (100) substrates by pulsed laser deposition using a ZnO target.The substrate temperature was varied in the range of room temperature to 800 ℃,and the oxygen partial pressure of 0.1333 Pa (1 m Torr) to 1333 Pa (10 Torr).The properties of the resulting films were investigated by photoluminescence (PL),grazing incidence X-ray diffraction (GIXRD),X-ray photoelectron spectroscopy (XPS),and field emission scanning electron microscopy (FESEM).Based on the ultraviolet (UV,～380 nm) to...     

脉冲激光沉积法制备VO_2热致变色薄膜研究进展

基于半导体和金属间的相变特性,伴随着温度、电场、压力的变化,具有相关智能特性的VO_2薄膜材料具有较大的应用潜力.本文主要阐述脉冲激光沉积技术在制备金属氧化物方面的物理过程和技术特点,详细介绍脉冲激光沉积制备VO_2薄膜材料的工艺参数和国内外研究进展,并与几种常规制备方法进行对比,给出脉冲激光沉积掺杂对VO_2薄膜材料特性的影响,以及采用脉冲激光沉积制备VO_2纳米材料,讨论了脉冲激光沉积制备具有智能特性的VO_2薄膜材料存在的问题和发展方向.