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961.
Designs, Codes and Cryptography - In this paper, we analyze the security of subset-resilient hash function families, which is first proposed as a requirement of a hash-based signature scheme called... 相似文献
962.
Tomokatsu Hayakawa S. Tamil Selvan Masayuki Nogami 《Journal of Sol-Gel Science and Technology》2000,19(1-3):779-783
We have investigated the energetic correlation between rare-earth ions and semiconductor nanocrystals, using europium ion (Eu3+) doped silica (SiO2) gel with adsorbed cadmium sulfide (CdS) particles. Samples were prepared by a sol-gel technique, in which several methods for the precipitation of CdS colloids were attempted. The fluorescence intensities were compared for different gels, with and without CdS particles. The intrinsic emission lines due to 5D0 7FJ(J = 0–4) transitions of Eu3+ were observed, which were enhanced for 24 h-immersed gel (dried at 50°C). From the results on the decay dynamics of fluorescence, we proposed the model that surface-trapped electrons on CdS particles nonradiatively excited 4f electrons in Eu3+ ions due to an energy transfer process. 相似文献
963.
Moriuchi T Kamikawa M Bandoh S Hirao T 《Chemical communications (Cambridge, England)》2002,(14):1476-1477
The conjugated homobimetallic palladium(II) complex [(L1)Pd(qd)Pd(L1)] (qd = quinonediimine) was obtained in a one-pot reaction by the in-situ oxidative complexation of 1,4-phenylenediamine with the palladium(II) complex [(L1)Pd(MeCN)] (H2L1 = N,N'-bis(2-phenylethyl)-2,6-pyridinedicarboxamide) while in the absence of an additional ligand [(L1)Pd(MeCN)] was converted to the amide-bridged macrocyclic tetramer [Pd(L1)]4. 相似文献
964.
F Kα X-ray fluorescence (XRF) spectra of various fluorides were measured and to investigate the chemical state of fluorine in xHoF3-20BaF2-10AlF3-(70 − x)GeO2 (mol%, x = 10-50) glass. The main peak (Kα1,2) position and the relative intensity of the satellite peak attributable to Kα3,4 were discussed relating to the M-F bond covalency. Results showed that the fluorine in xHoF3-20BaF2-10AlF3-(70 − x)GeO2 (mol%, x = 10-50) glass had a completely different chemical state from that of starting materials. Quantitative analyses of the glasses were also undertaken using XRF measurements for each component. These results suggest that 30% fluorine in the 50HoF3-20BaF2-10AlF3-20GeO2 system is substituted by oxygen through pyrohydrolysis of the fluorides. 相似文献
965.
Kubo Y Sugasaki A Ikeda M Sugiyasu K Sonoda K Ikeda A Takeuchi M Shinkai S 《Organic letters》2002,4(6):925-928
[structure: see text] Porphyrin tetramer 1 was newly designed and synthesized to construct a novel cooperative [60]fullerene (C(60)) binding system. Compound 1 has a p-terphenyl axis, which is expected to act as a scaffold for a guest-binding information transducer. In toluene, 1 can bind 2 equiv of C(60) to produce a 1:2 1/C(60) complex with association constants of 5800 M(-1) (K(1)) and 2000 M(-1) (K(2)). These values are significantly greater than those for control porphyrin dimers such as 2 and 3. 相似文献
966.
Takaomi Suzuki Naoki Sugihara Eiichi Iguchi Katsuya Teshima Shuji Oishi Masayuki Kawasaki 《Crystal Research and Technology》2007,42(12):1217-1221
The specific surface free energy of ruby and quartz single crystal was experimentally obtained using contact angle of water and formamide droplets on the crystal surfaces, and compared with the morphology of each crystal. The ruby crystals satisfied Wulff's relationship even though their shape were not equilibrium form. The specific surface free energies of the growing faces of synthetic quartz crystal, ‐X, +X, Z, and S faces were obtained as 51.9, 55.6, 57.4, and 58.9 mN/m, respectively. The growth rates of these faces were 0.09, 0.23, 0.28, and 0.33 mm/day, respectively. The growth rate of each face of the quartz crystal can be regarded as a function of the experimentally obtained specific surface free energy. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim) 相似文献
967.
Plasma-induced surface radicals formed on a variety of organic polymers have been studied by electron spin resonance (ESR), making it possible to provide a sound basis for future experimental design of polymer surface processing, i.e., plasma treatment. On the basis of the findings from such studies, several pharmaceutical applications in the field of drug engineering have been devised, which include preparation of double-compressed tablets for reservoir-type drug delivery system (DDS) of sustained- and delayed-release, and fabrication of functionalized composite powders applicable for matrix-type DDS by a mechanical application of plasma-irradiated polymer powder. 相似文献
968.
We present information criteria for statistical model evaluation problems for stochastic processes. The emphasis is put on the use of the asymptotic expansion of the distribution of an estimator based on the conditional Kullback–Leibler divergence for stochastic processes. Asymptotic properties of information criteria and their improvement are discussed. An application to a diffusion process is presented. 相似文献
969.
Jae-Dong Kim Yong-Il Park Koichi Kobayashi Masayuki Nagai Masayuki Kunimatsu 《Solid State Ionics》2001,140(3-4):313-325
The CO tolerance of a proton exchange membrane fuel cell (PEMFC) was investigated by ac impedance spectroscopy. The impedance of the fuel cell could be obtained by feeding oxygen into the cathode side and simulated gas into anode side. Furthermore, the anode impedance could be obtained by feeding hydrogen into the cathode side and simulated gas into anode side. The CO gas had a greater effect on the charge transfer reaction (high frequency arc) and hydrogen dissociative chemisorption (medium frequency arc) but little effect on the low frequency arc. Although the cathode impedance is a main part at high temperature, irrespective of CO concentration (≤100 ppm), the impedance of the full cell depends on anode impedance at low temperature and high CO concentration. It was found that CO gas has little effect on cathode impedance. 相似文献
970.
Chikashi Nakamura Miki Hasegawa Masayuki Hara Jun Miyake 《Applied biochemistry and biotechnology》1999,77(1-3):169-179
A tetraheme cytochrome (BCytc) was isolated from the photosynthetic reaction centers (RC) of Rhodopseudomonas viridis while maintaining the redox activity. BCytc was removed from the H-subunit-detached RC by polyacrylamide electrophoresis using an alkyl ether sulfate mixed with sodium
dodecyl sulfate. Redox titration of BCytc showed a simple one-step redox titration curve and a lowered midpoint potential than that of one in RC. Direct electron transfer
between BCytc and electrode surfaces, such as indium tin oxide, was successfully performed, indicating a potential for molecular electronic
material. 相似文献