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41.
Shuzo Hattori Shinzo Morita Masao Yamada Junji Tamano Masayuki Ieda 《Polymer Engineering and Science》1983,23(18):1043-1046
This paper presents the preliminary results of efforts to improve dry processed electron beam resist materials using plasma polymerization coating technology. Three approaches investigated were chemical susceptibility modification, the use of multilayer resist structures, and the effect of grafting reactions. 相似文献
42.
K. Yamakawa D. Ravichandran A. S. Bhalla S. Trolier-McKinstry J. P. Dougherty R. Roy 《Ferroelectrics Letters Section》1996,22(1):41-45
Ferroelectric SrBi2Ta2O9 thin films were prepared from Sr metals, Ta-ethoxide and Bi, 2-ethylhexanoate. The films were prepared from both stoichiometric and 10 mol% Bi rich solutions. The stoichiometric film crystallized at 800°C had a spontaneous polarization value of 5 μC/cm2. The Bi rich film had lower crystallinity, finer grains and a smaller polarization. It was found to be necessary to anneal the films at high temperatures or for long time to achieve ferroelectricity. The non-crystalline states of sol-gel derived films differ from that observed in films deposited by physical vapor deposition. Crack free films were produced with the film thicknesses of 0.4 μm. 相似文献
43.
The environmental stability in distilled water and the failure mechanism of cathodically chromated tin, lead, and lead/tin alloy joints bonded with an ethylene–acrylic acid copolymer have been investigated by T-peel tests and ESCA and SEM analyses of the fractured surfaces. The peel strength of chromated lead/tin alloy joints and of both untreated and chromated tin joints is kept unchanged with water immersion, whereas that of untreated lead/tin alloy joints and of both untreated and chromated lead joints decreases rapidly with water immersion. ESCA and SEM observations show that lead/tin alloy surfaces consist of both lead and tin phases and that the tin phase interface deteriorates gradually with water immersion after premature deterioration of the lead phase interface. The stabilization effect of chromate treatments for lead/tin alloy joints is due to retardation of the underfilm corrosion of the tin phase. 相似文献
44.
45.
Fatty acid synthetase was isolated from guinea pig Harderian gland. This enzyme complex exhibited a unique character as compared with the fatty acid synthetase from the liver of the same animal. The former enzyme produced many odd-numbered and methyl-branched fatty acids in the presence of methylmalonyl-CoA. These fatty acids are characteristic components of the lipid secreted from this gland. The chemical structure of this lipid has been identified as 1-O-alkyl-2,3-diacylglycerol by previous work from this laboratory (Yamazaki, T., Seyama, Y., Otsuka, H., Ogawa, H., & Yamakawa, T. (1981) J. Biochem. 89, 683-691). Apparent Km values (5 X 10(-6) M) for acetyl-CoA and propionyl-CoA were the same, but the Vmax for propionyl-CoA was much higher than that for acetyl-CoA. The pI value of the fatty acid synthetase from Harderian gland was 5.3, and the molecular weight of the enzyme was 9 X 10(5) daltons. The beta-ketoacyl reductase had pro-S stereospecificity and the enoly reductase had pro-R stereospecificity for NADPH. The results presented in this paper indicate that the fatty acid synthetase from guinea pig Harderian gland can produce a set of fatty acids needed for the synthesis of the lipid secreted from this gland, and that the fatty acid synthetase has a characteristic organ specificity. 相似文献
46.
47.
Composite organic-inorganic nanoparticles (COINs) with chemically encoded optical signatures 总被引:1,自引:0,他引:1
To obtain a coding system for multiplex detection, we have developed a method to synthesize a new type of nanomaterial called composite organic-inorganic nanoparticles (COINs). The method allows the incorporation of a broad range of organic compounds into COINs to produce surface enhanced Raman scattering (SERS)-like spectra that are richer in variety than fluorescence-based signatures. Preliminary data suggest that COINs can be used as Raman tags for multiplex and ultrasensitive detection of biomolecules. 相似文献
48.
Intense white photoluminescence (PL) at room temperature has been observed in ZnO thin films formed by anodization at 26? C. The PL depends on the preparation conditions of the films. The PL is attributed to radiative recombination between localized electrons and holes in gap states which are formed by native defects in the films. We suggest that the anodized ZnO films might be useful for optoelectronic devices, since the low temperature anodization process used is inexpensive and fast. 相似文献
49.
Anisotropy of styrene–butadiene rubber (SBR) was investigated. The anisotropy of the copolymer varies linearly with the styrene content and the ultimate value coincides with that of polystyrene at elevated temperature. From these facts, the transverse configuration of the pendant phenyl group is estimated irrespective of the styrene content of SBR. 相似文献
50.
Toshiaki Tanaka Hitoshi Kawaji Tooru Atake Koichi Kikuchi Kazuya Saito Shinzo Suzuki Yohji Achiba Isao Ikemoto 《Fullerenes, Nanotubes and Carbon Nanostructures》1994,2(2):121-127
The heat capacity of C70 has been measured by adiabatic calorimetry between 14 and 320 K. The orientational phase transition is observed as a broad hump in the heat capacity curve, which is strongly influenced by small amount of solvent remaining in the sample. 相似文献