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31.
利用磁控溅射的方法在氧化后的单晶Si基片上制备了TiNi形状记忆合金薄膜,利用示差扫描量热法和原位X射线衍射研究了薄膜的马氏体相变特征。通过60keV质子注入(辐照)薄膜样品研究了H+离子对合金薄膜马氏体相变特征的影响,结果表明氢离子注入后引起了马氏体相变开始Ms和结束点Mf以及逆马氏体相变开始As和结束温度Af的下降,而对R相变开始Rs和结束温度Rf影响不大。掠入射X射线衍射表明H+离子注入后有氢化物形成。H+离子注入形成的氢化物是引起相变点的变化的主要因素。 相似文献
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简述了高聚物薄膜玻璃化转变的复杂性,并结合文章作者的的一些研究结果介绍了扫描力显微术(SFM)在研究高聚物玻璃化转变中的一些方法,包括观察高聚物薄膜形貌的变化,测量其摩擦力、粘附力和弹性模量等物理量的变化,最后指出SFM是研究高聚物薄膜玻璃化转变的有力工具。 相似文献
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Zh. D. Chaplanova Yu. K. Mikhailovskii V. E. Agabekov V. K. Ol’khovik N. A. Galinovskii E. A. Gracheva 《Journal of Applied Spectroscopy》2007,74(3):333-337
We have studied the spectral properties and morphology of thin films (TVD films) formed by thermal vacuum deposition of 4,4′-bis[(E)-1-(1,3-benzoxazol-2-yl)-2-ethenyl]-1,1′-biphenyl
and its substituted derivatives. We have shown that introducing bulky 2,2′-oxyhexyl substituents into the biphenyl units leads
to a shift of the fluorescence maximum for the TVD films toward shorter wavelengths, a decrease in their photostability, and
aggregation of the films during storage.
__________
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 74, No. 3, pp. 300–303, May–June, 2007. 相似文献
36.
High temperature scanning tunneling spectroscopy (HT-STS) was used to investigate the electronic structure of Au(1 1 1) at different temperatures in the energy range 0-1 eV below the Fermi level. We concentrated on the influence of temperature on the Shockley surface state (SS) appearing on noble metals surface due to a surface projected bulk bang gap in [1 1 1] direction. The influence of temperature on the projected band gap edge (BE) was also investigated. The experiment was carried out in the temperature range 294-580 K. As the result of the experiment a delicate shift of the SS and the BE in direction of the Fermi level was reported. 相似文献
37.
Leszek Wachowski Antoni Grodzicki Piotr Piszczek Monika Richert Magdalena Hofman 《Reaction Kinetics and Catalysis Letters》2007,91(1):93-99
Hydrogenation of styrene has been applied as a test reaction to study the catalytic activity of TiO2 deposited by the CVD (chemical vapour deposition) method on the surface of a carbonaceous material enriched in nitrogen (CN). 相似文献
38.
Hiroshi Aoki Ken Hosoya Tomohisa Norisuye Nobuo Tanaka Daisuke Tokuda Norio Ishizuka Kazuki Nakanishi 《Journal of polymer science. Part A, Polymer chemistry》2006,44(2):949-958
An investigation was made of the gelation of dimethacrylate‐type crosslinking agents in view of an application for separation media. The study mainly centered on a crosslinking agent, glycerol dimethacrylate (GDMA), which is relatively hydrophilic because of a hydroxyl group in the middle of its structure. The gelation of GDMA was compared with that of other hydrophobic crosslinking agents such as ethylene glycol dimethacrylate and 1,6‐hexanediol dimethacrylate. The diluents used in the study were toluene, toluene with methanol, and cyclohexanol. The gelation was observed in real time with a charge coupled device camera and dynamic light scattering (DLS). Also, the separated dry gels were extensively characterized with scanning electron microscopy, BET (N2 absorption and desorption isotherm), and Fourier transform infrared. DLS analysis showed a stronger molecular interaction of GDMA gelation in toluene, whereas this interaction was much weaker in an alcoholic solvent such as toluene with methanol or cyclohexanol. This indicated that GDMA gelation might proceed through hydrogen bonding as well as a crosslinking reaction of vinyl groups. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 949–958, 2006 相似文献
39.
Huseyin Zengin Gulay Zengin Dennis W. Smith 《Journal of polymer science. Part A, Polymer chemistry》2006,44(24):6988-6996
This study focuses on the preparation, characterization, and optical properties of new bis(3,4‐diphenylethynylphenyl)phenylamine. This is the first nitrogen‐containing bis‐ortho‐diynylarene (BODA) monomer having a nitrogen atom as the spacer group. BODA monomers are usually prepared from common bisphenols, thereby providing great synthetic versatility and the opportunity to develop a wide array of novel polyarylene thermosets by varying the aromatic spacer group. The new bis(3,4‐bisphenylethynylphenyl)phenylamine was synthesized in five steps. This compound emits an intense blue color (λ = 438 nm) upon irradiation by UV light and may be suitable for use as an emitting layer in electroluminescent devices. Bis‐(3,4‐bisphenylethynylphenyl)phenylamine and its polymer have photoluminescence quantum yields 34 and 38%, respectively, and long excited‐state lifetimes of 3.2 and 3.6 ns, respectively. The structure of the monomer and its polymer were characterized using spectroscopic techniques including Ultraviolet–visible Spectrophotometer, Photoluminescence Spectrophotometer, Fourier Transform infrared spectroscopy, and Gel Permeation Chromatography. The polymerizations were studied by Differential Scanning Calorimeter. The amount of weight loss and the thermostability of the nitrogen‐containing polymer were determined from thermogravimetric analysis. The electrical conductivity of neat HCl‐doped BODA‐derived polymer film was measured according to the standard four‐point probe technique. © 2006 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 6988–6996, 2006 相似文献
40.