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151.
152.
采用透射电子显微术(TEM),研究了用磁控溅射技术在柔性金属基体上制备的、钇稳定的ZrO2(YSZ)为过镀层的YBa2Cu3O7-y(YBCO)薄膜的横断面结构。所得YBCO膜的超导临界转变温度Tc为91K,临界电流密度Jc=2×103A/cm2(77K,0T)。基体为Ni基合金(HasteloyC)。YSZ层为致密、均匀的细晶组织,约12μm厚,具有织构取向,并与基体紧密连接。YBCO层的厚度不均匀,约500nm;YBCO/YSZ界面有时连接较差,在该界面上有杂质出现,杂质有可能引发裂纹。 相似文献
153.
Polycrystalline Fe2TiO5 films were prepared on nesa silica glass substrates by the sol-gel method, and their photoanodic properties were measured in a three-electrode wet cell with an aqueous buffer solution of pH = 7. Gel films were crystallized into Fe2TiO5 when fired at 500°C. The photoanodic current significantly increased when the films were fired at 700°C, and then decreased with increasing firing temperature. Thicker films obtained by repeating the gel film deposition and firing showed smaller photocurrent, and the 50 nm thick film prepared via non-repetitive deposition exhibited the maximum photocurrent. Although the photoresponse was extended to wavelengths near 500 nm, the maximum quantum yield was as low as 0.12 at a wavelength of 340 nm. 相似文献
154.
R. WinterP.G. Nixon R.J. TerjesonJ. Mohtasham N.R. HolcombD.W. Grainger D. GrahamD.G. Castner G.L. Gard 《Journal of fluorine chemistry》2002,115(2):107-113
A new perfluorinated acrylate monomer containing the SF5(CF2)6-perfluorinated side chain was synthesized and polymerized into films. Bulk monomer characterization is consistent with the molecular structure based on FTIR, mass spectrometry and NMR analyses. The surface properties of polymer coatings were studied with aqueous wetting (contact angle) and X-ray photoelectron spectroscopy (XPS) methods. The surface composition is shown to be highly enriched in the terminal side chain SF5-chemistry and exhibits properties consistent with a highly apolar, non-wetting perfluorinated polymer surface. Depth-dependent XPS studies using angular-resolved methods (ADXPS) confirmed a non-stoichiometric enrichment of sulfur and fluorine at the film ambient interface, consistent with a surface presence of the terminal SF5-group and possibly film structural anisotropy in the surface zone. Time-of-flight (TOF) secondary ion mass spectrometry (SIMS) analysis supplements the XPS data by showing the presence of all expected SF5-acrylate chemistry components in the outer 15 Å of the film surface. 相似文献
155.
《Surface and interface analysis : SIA》2005,37(3):310-315
Carbon film coatings have been produced by a hot‐wall chemical vapor deposition (CVD) method under moderate conditions from pyrolysis of a mixture of propane and argon on an Fe(110) substrate at temperatures of 800–900 °C for different deposition times. The effects of temperature and reaction time on the growth of the carbon films were studied. Field‐emission scanning electron microscopy (FESEM), Raman microscopy, Auger electron spectroscopy (AES) and x‐ray diffraction methods have been performed to study the surface morphologies, growth features and microstructures of the carbon film coatings. The FESEM analyses indicated that carbon films on an Fe substrate consisted of flat‐layer and filamentous morphologies. Raman and AES analyses showed that the carbon initially was crystalline but the degree of disorder in the top layer of the carbon film increased with increasing deposition temperature. High‐resolution transmission electron microscopy studies are also in agreement with Raman results. The same trend was observed when the deposition time was increased from 5 to 30 min. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
156.
本文合成了2,5-二(2-菲基)-[3,2-b]并二噻吩(PhTT), 表征了其基本的物理和化学性质, 制备了相应的有机薄膜晶体管. 相似文献
157.
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159.
We report the electroanalytical determination of lead by anodic stripping voltammetry at in-situ-formed, bismuth-film-modified, boron-doped diamond electrodes. Detection limits in 0.1 mol L–1 nitric acid solution of 9.6x10–8 mol L–1 (0.2 ppb) and 1.1x10–8 mol L–1 (2.3 ppb) were obtained after 60 and 300 s deposition times, respectively. An acoustically assisted deposition procedure was also investigated and found to result in improved limits of detection of 2.6×10–8 mol L–1 (5.4 ppb) and 8.5×10–10 mol L–1 (0.18 ppb) for 60 and 300 s accumulation times, respectively. Furthermore, the sensitivity obtained under quiescent and insonated conditions increased from 5.5 (quiescent) to 76.7 A mol–1 L (insonated) for 60 s accumulation and from 25.8 (quiescent) to 317.6 A mol–1 L (insonated) for 300 s accumulation. Investigation of the use of ultrasound with diluted blood revealed detection limits of the order of 10–8 mol L–1 were achievable with excellent inter- and intra-reproducibility and sensitivity of 411.9 A mol–1 L . For the first time, electroanalytical detection of lead in diluted blood is shown to be possible by use of insonated in-situ-formed bismuth-film-modified boron-doped diamond electrodes. This method is a rapid, sensitive, and non-toxic means of clinical sensing of lead in whole human blood. 相似文献
160.
M. Röder J. Hahn U. Falke S. Schulze F. Richter M. Hietschold 《Mikrochimica acta》1997,125(1-4):283-286
A series of BN films was deposited by means of r.f. magnetron sputtering of a h-BN target onto Si(1OO) surfaces. Hereby, the substrate bias voltage was varied. Special interest is focussed to the influence of the deposition parameters on the orientation of the growing hexagonal BN film with respect to the substrate. For structural investigation, cross section samples were prepared. In addition to HRTEM and diffraction investigations, especially electron energy loss spectroscopy (EELS) was applied successfully for phase identification. For negative bias voltages of U
B
=–300 V and U
B
=–350V, we found a phase system consisting of a first-grown 25 nm thick layer of hexagonal structure with the c axis parallel to the substrate surface followed by the cubic phase.Dedicated to Professor Dr. rer. nat. Dr. h.c. Hubertus Nickel on the occasion of his 65th birthday 相似文献