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1.
Studies on characteristics of nanostructure of N-TiO2 thin films and photo-bactericidal action 总被引：1，自引：0，他引：1
Pseudomonas aeruginosa strain （AS 1.50） and Bacillus subtilis strain （AS 1.439） from Ming lake were decomposed by photocatalytic nanostructure N-TiO2 thin films in a photo-reactor under UV irradiation. The different thickness nanostructure N-TiO2 thin films coated on mesh grid were prepared by sol-gel method and immobilized at 500 ℃ （films A） or 350 ℃ （films B） for 1 h in a muffle furnace. The results showed that N-TiO2 thin film B （8.18 nm thickness, 2.760 nm height and 25.15 nm diameter） has more uniform granular nanostructure and thinner flat texture than N-TiO2 thin film A （12.17 nm thickness, 3.578 nm height and 27.50 nm diameter）. The bactericidal action of N-TiO2 thin film A and film B for Pseudomonas aeruginosa strain （AS 1.50） and Bacillus subtilis varniger strain （AS1.439） were investigated in this work. More than 95% of photocatalytic bactericidal efficiency for Pseudomonas aeruginosa strain （AS 1.50） and 75% for Bacillus subtilis strain （AS 1.439） were achieved by using N-TiO2 thin films-B for 70-80 rain of irradiation during the photo-bactericidal experimental process. The results indicated that the photo-induced bactericidal efficiency of N-TiO2 thin films probably depended on the characteristics of the films. 相似文献
2.
Vanadium oxides condensed films are prepared on glass substrates, using spray pyrolysis （SP） technique. The effects of substrate temperature, vanadium concentra- tion in initial solution and the solution spray rate on the nano-structural, electrical, and optical properties of depos- ited films were investigated. Characterizations of the sam- ples were performed using X-ray diffraction （XRD）, scanning electron microscopy （SEM）, and UV-Vis spec- troscopy methods. The type and concentration of the charge carriers were determined and measured by Hall effect experiment. XRD patterns showed that the prepared films had polycrystalline structure, mostly tetragonal fl-V205 and V409 phases with the preferred orientation along （200） direction. The Hall effect experiment revealed that all samples were n-type, except the ones deposited at substrate temperatures Tsub ： 300 ~C and Tsub = 450 ~C, vanadium concentration 0.1 mol/L and solution spray rate 10 mL/min. The charge carrier concentrations obtained were in the range 1016-1018 cm-3. The lowest sheet resistance （R~） was obtained for the samples prepared at T~ub = 450 ~C, vana- dium concentration 0.05 mol/L and solution spray rate 10 mL/min. It was also found that the optical transparency of the samples changed from 20% to 75% and the optical bandgap of the samples was from 2.22 eV to 2.58 eV, depending on the deposition conditions. 相似文献
3.
Low valence vanadium oxide（VO2-x） thin films were prepared on SiO2/Si substrates at room temperature by direct current facing targets reactive magnetron sputtering, and then processed through rapid thermal annealing. The effects of the annealing on the structure and phase transition property of VO2 were discussed. X-ray photoelectron spectroscopy, X-ray diffraction technique and Fourier transform infrared spectroscopy were employed to study the phase composition and structure of the thin films. The resistance-temperature property was measured. The results show that VO2 thin film is obtained after annealed at 320℃ for 3 h, its phase transition temperature is 56 ℃, and the resistance changes by more than 2 orders. The vanadium oxide thin films are applicable in thermochromic smart windows, and the deposition and annealing process is compatible with micro electromechanical system process. 相似文献
4.
Ba0.6Sr0.4TiO3 （BST） thin films with and without HfO 2 buffer layer were fabricated on Pt/Ti/SiO2/Si substrates by pulsed laser deposition. Dependences of HfO 2 thickness on the dielectric property and leakage current of BST thin films were focused. The dielectric constant of BST thin films increased and then decreased with the increase of HfO 2 thickness, while the dielectric relaxation was gradually improved. The loss tangent and leakage current under positive bias decreased with the HfO 2 thickness increasing. The leakage current analysis based on the Schottky emission indicated an improvement of the BST/Pt interface with HfO 2 buffer layer. The loss tangent, tunability and figure of merit of optimized HfO 2 buffered BST thin film achieved 0.009 8, 21.91% （E max = 200 kV/cm）, 22.40 at 10 6 Hz, respectively. 相似文献
5.
冰片在中风及假手术大鼠体内的药代动力学研究(英文)简 总被引：1，自引：0，他引：1
Pan XU Ying LI Shou-ying DU Yang LU Jie BAI Qing-li GUO 《Journal of Zhejiang University. Science. B》2014,15(1):84-91
Objective： This study was designed to investigate the pharmacokinetics of borneol in the pathological conditions of stroke and evaluate the pharmacokinetic differences of borneol caused by stroke after oral administration of borneol and Xingnaojing （XNJ）. Methods： The rats were divided into two groups, ischemia-reperfusion （IR） and sham-operated （SO） rats. Each group contained two subgroups： pure borneol and XNJ subgroups. After administration with the same dosages of borneol 162.0 mg/kg, plasma samples were collected. The cerebral ischemia-reperfusion model was created by reversible middle cerebral artery occlusion （MCAO）. The blood samples were collected punc- tually after oral administration and a specific gas chromatographic system-flame ionization detector （GC-FID） method was developed and employed to determine the level of borneol in the plasma. The pharmacokinetic parameters were analyzed using non-compartmental methods with Kinetica. Results： After administration of borneol, the maximum plasma concentration （Cmax） and area under the curve （AUC） values in stroke rats significantly increased by 302% and 275%, respectively, compared with the SO rats, and the same phenomenon appeared after administration of XNJ. In the rats with the same physiological conditions, the Cmax and AUC had higher values in the borneol subgroup （P〈0.05）. Conclusions： These results suggest that the pathological damages of ischemia-reperfusion have a significant impact on the pharmacokinetic traits of borneol and that there are some components in XNJ inhibiting the absorption of borneol. 相似文献
6.
Nano-Ag particles/polyacrylamide （PAM） composites were synthesized by γ irradiation method and then blended with ethylene vinyl acetate （EVA）. Dielectric behaviors of the Ag/PAM/EVA composites are investigated as a function of both the concentration and size of Ag particles. When concentration of the Ag fillers is rarely low, dielectric anomalies were first observed in contrast to the traditional percolation theory. As concentration of Ag increases, volume resistivity and breakdown field strength are enhanced, loss tangent （tan δ） reduced and dielectric constant kept invariable. In addition, the above variation became larger when the diameter of the Ag nano-particles is smaller. Such dielectric anomalies may be understood by considering the unique ＂Coulomb Blockade Effect＂ of the nano-sized Ag particles. 相似文献
7.
In the present work,hierarchical nanostructured titanium dioxide（TiO2） films were fabricated on Ti-25Nb-3Mo-2Sn-3Zr（TLM） alloy for biomedical applications via one-step anodization process in ethylene glycolbased electrolyte containing 0.5wt% NH4F.The nanostructured TiO2 films exhibited three distinct types depending on the anodization time：top irregular nanopores（INP）/beneath regular nanopores（RNP）,top INP/middle regular nanotubes（RNT）/bottom RNP and top RNT with underlying RNP.The evolution of the nanostructured TiO2 films with anodization time demonstrated that self-organizing nanopores formed at the very beginning and individual nanotubes originated from underlying nanopore dissolution.Furthermore,a modified two-stage self-organizing mechanism was introduced to illustrate the growth of the nanostructured TiO2 films.Compared with TLM titanium alloy matrix,the TiO2 films with special nano-structure hold better hydrophilicity and higher specific surface area,which lays the foundation for their biomedical applications. 相似文献
8.
In2O3 nanoparticles were prepared from or with different indium salts by chemical precipitation under the conditions of various pH values. The crystal structure and ceramic microstructure of the samples were characterized by X-ray diffraction （XRD） and transmission electron microscopy （TEM）. The results show that the mean grain size of In2O3 is less than 100 nm, and their particle homogeneity and dispersibility are satisfactory. The gas sensitivity defined as Ra/Rg was detected in a static system. The results show that the sensors made by as-prepared nanoparticles has high sensitivity to many gases such as alcohol, HCHO, NH3 , et al. The response time is less than 20 s and the recovery time is lower than 30 s. 相似文献
9.
In this study, the surface chemical properties of carbon nanotubes （CNTs） and carbon nanofibers （CNFs） grown by catalytic decomposition of methane on nickel and cobalt based catalysts were studied by DRIFT （Diffuse Reflectance Infrared Fourier Transform） and transmission Infrared （IR） spectroscopy. The results show that the surface exists not only carbon-hydrogen groups, but also carboxyl, ketene or quinone （carbonyl） oxygen-containing groups. These functional groups were formed in the process of the material growth, which result in large amount of chemical defect sites on the walls. 相似文献
10.
To investigate the application of reformed coke oven gas （COG） in producing the direct reduction iron （DRI）, we simulated a countercurrent gas solid moving bed reactor in which the iron ore pellet was reduced by reformed COG. An ordinary differential equation （ODE） was set based on the unreacted shrinking core model considering both mass and energy balances of the reactor. The concentration and temperature profiles of all species within the reactor were obtained by solving the ODE sys tem. The solid conversion and gas utilization were studied by changing gas flow rate, solid flow rate, reactor length, and the ratio of O/CHa to guide the practical application of COG in DRI production. Model results showed that COG was suitable for the DRI production. In order to meet the requirement of the industrial production, the minimum gas flow rate was set as 130,000 Nm3/h, and the maximum production was 90 t/h. The reactor length and the mole ratio x（O）： x（CH4） were depended on the actual industrial situations. 相似文献
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12.
INTRODUCTION Monocrystalline SBN (Strontium barium nio-bium, SrxBa1?xNb2O6, denoted SBNx?100, where 0.25≤x≤0.75) solid solution, is currently being inves-tigated as potential material for many micro-device applications, such as piezoelectric infrared detectors, piezoelectric, electro-optic modulators, and holo-graphic storage (Koch et al., 1998), because SBN has one of the largest known linear electro-optic coeffi-cients (r33=1300 pm/V for SBN75), two orders of magnitude larger th… 相似文献
13.
Amorphous InGaZnO (a-IGZO) films were deposited on the corning eagle XG (EXG) glass substrates using magnetron sputtering
method. The structure, surface morphology, electrical and optical properties of these films were investigated by X-ray diffraction
(XRD), scanning electron microscopy (SEM), semiconductor parameter analyzer and spectrophotometry, respectively. The influence
of oxygen flow on the electrical properties of IGZO thin films was studied, showing that increasing oxygen flow changes the
resistivity with six orders of magnitude. The contact resistance of ITO/IGZO is 7.35×10−2 Ω·cm2, which suggests that a good ohmic contact exists between In2O3: Sn (ITO) and IGZO film. 相似文献
14.
反应磁控溅射方法在玻璃基片上沉积Cu-Al-O薄膜,并对薄膜进行退火处理,研究溅射功率和退火温度对薄膜结构和光电学性质的影响。用X射线衍射仪、分光光度计等仪器对薄膜的性质进行表征,采用拟合正入射透射谱数据计算薄膜的厚度。结果表明：不同溅射功率条件下制备的薄膜为非晶态,透射率在近红外部分达到60%以上,电阻率随溅射功率的增加呈U型变化,在120 W附近,电阻率达到极小值;退火后,薄膜的XRD谱出现Cu4O3、Cu O和Al2O3的混合相,薄膜透射率有所提高,电阻率随退火温度的提高而先增大后减小。 相似文献
15.
层状型的金属硫化物(SnS)1.2TiS2是一种新型的热电材料,其结构是由SnS层和TiS2层(一种自然超晶格)相叠加而形成.在这些热电材料中,发现了不同化合物的纳米化叠加态,由于这些沿层面叠加的超晶格的特殊性质,在不影响电子输运的情况下,可使声子的输运减小到最小,从而提升了材料的热电性能.计算了(SnS)1.2TiS2的电子结构与声子结构,通过对纯TiS2体材料与(SnS)1.2TiS2中的TiS2层的电子、声子结构的对比,证实了SnS插层对TiS2层的电子结构及电学输运性质影响很小.这些发现有利于提高层状材料的热电性能. 相似文献
16.
研究了利用RFCVD技术,在铝片等基体表面沉积类金刚石膜。对膜的硬度、电阻率、附着力进行分析发现,在合适的气体流量比和射频功率密度下,这些性能可显著提高。 相似文献
17.
张治国 《泉州师范学院学报》2008,26(6):29-33
分析热蒸发时锌液滴在舟内跳动的原因,给出解决问题的方法．用反应蒸发法制备成功ZnO导电薄膜,并给出薄膜的形貌显微照片、XRD图谱、光电效应的测量结果以及其结果与电阻率、薄膜光电子迁移率的关系． 相似文献
18.
报道了紫外光源在制备金属薄膜材料方面的应用研究,金属钯是一种优良的催化剂,首先在各种衬底上面淀积靶的金属有机化合物薄膜,通过紫外分解钯的金属有机化合物,形成数埃到几十埃的色膜,然后再利用钯的催化效应,在无电极电镀中淀积出几十纳米到几微米厚的各种金属薄膜（如Cu、Au、Ni等）。 相似文献
19.
用X射线衍射仪检测薄膜的结构;用分光光度计测量薄膜的透射率和反射率,采用拟合正入射透射谱数据的方法计算薄膜的厚度;用Van der Pauw方法测量薄膜表面电阻和霍尔迁移率,并计算出电阻率和载流子浓度.结果表明,生成单相Cu2O薄膜的氧气流量范围很小,在氧气流量为5-7sccm范围,薄膜主要成分为Cu2O,其中氧氩流量比为6∶25时,生成单相多晶结构的Cu2O薄膜,其表面电阻0.68MΩ/□,电阻率58.29Ω.cm,霍尔迁移率4.73cm2·V-1·s-1,载流子浓度3×1016cm-3. 相似文献
20.
Y3+-doped (Bi1/2Na1/2)TiO3-CaTiO3-BaTiO3 (BNCBT) positive temperature coefficient of resistivity (PTCR) ceramics sintered in air atmosphere were investigated in this study. (Bi1/2Na1/2) TiO3 (BNT) component can remarkably increase the onset temperature Tc of PTCR ceramics with the expensive of the resistivity R25 increase. CaTiO3 (9-27 mol%) component can decrease the resistivity, and adjust the effects of BNT phase on the Tc point. For the sample containing 3 mol% CaTiO3, the Tc raises from 122° to 153° when only 0.6 mol% BNT added, while for the ones with higher CaTiO3 content (9-27 mol%), Tc is only increased by a rate of 8-9°/1.0 mol% BNT. The effects of BNT and CaTiO3 components on Rmln (negative temperature coefficient effect) are also discussed. 相似文献