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61.
62.
T. Tanabe K. Haga M. Yasue K. Sato K. Ogino Y. Kadota M. Tochi K. Makino T. Kitahara T. Shiba 《Nuclear Physics A》1983,399(1):241-258
The 24, 26Mg(6Li, d)28, 30Si reactions have been studied at 73 MeV bombarding energy. The angular distributions were analyzed with exact finite-range distorted wave Born approximation calculations assuming a direct α-cluster transfer. Extracted spectroscopic strengths leading to low-lying levels of 28Si and relative spectroscopic strengths between transitions to 28Si and 30Si ground states are consistent with those previously obtained by several α-transfer reactions. Many strongly populated levels have been observed at Ex ? 10 MeV for 28Si. A marked similarity was found between the deuteron spectrum and the 24Mg(α, α)24Mg excitation function in this excitation energy region. A brief comparison of the present α-transfer results with previous two-nucleon transfer data leading to 28,30Si is also presented. 相似文献
63.
Synthesis of fluorinated chitin derivatives has been achieved using chitinase from Bacillus sp. as a catalyst. 6'-Fluoro- (1a), 6-fluoro- (1b) and 6,6'-difluoro- (1c) chitobiose oxazoline derivatives were newly prepared as TSAS monomers for chitinase. Ring-opening polyaddition of these monomers proceeded effectively at pH 8.0-9.0 and 30-40 degrees C, giving rise to alternatingly 6-fluorinated chitin derivatives (2a and 2b) from 1a and 1b, and fully 6-fluorinated chitin derivative (2c) from 1c under total control of regioselectivity and stereochemistry. XRD measurements revealed that polysaccharides 2a and 2b had crystalline structures similar to that of alpha-chitin. [reaction: see text] 相似文献
64.
Hirakawa K 《Analytical and bioanalytical chemistry》2006,386(2):244-248
Hydrogen peroxide (H2O2) is one of the most important reactive oxygen species. In the present study, a fluorometry method for detecting H2O2 utilizing folic acid was evaluated. Folic acid was decomposed by H2O2 in the presence of Cu(II) into pterine-6-carboxylic acid, leading to strong fluorescence enhancement. In the absence of the
metal ion, superoxide and H2O2 could not decompose folic acid. Also, H2O2 plus sodium hypochlorite (a source of singlet oxygen) could not induce fluorescence enhancement. These results demonstrate
that H2O2 can be selectively detected using folic acid plus Cu(II). The limit of detection (LOD; at S/N=3) for H2O2 is 0.5 μM. This method based on the fluorescence enhancement of folic acid was applied in order to determine small amounts
of H2O2 generated through the autooxidation of semicarbazide (generation rate: ∼0.01 μM min−1), a carcinogenic compound.
相似文献
65.
Kamisetty NK Pack SP Nonogawa M Devarayapalli KC Kodaki T Makino K 《Analytical and bioanalytical chemistry》2006,386(6):1649-1655
Aminosilane-treated molecular layers on glass surfaces are frequently used as functional platforms for biosensor preparation.
All the amino groups present on the surface are not available in reactive forms, because surface amino groups interact with
remaining unreacted surface silanol groups. Such nonspecific interactions might reduce the efficiency of chemical immobilization
of biomolecules such as DNA, enzymes, antibodies, etc., in biosensor fabrication. To improve immobilization efficiency we
have used additional surface silanization with alkylsilane (capping) to convert the remaining silanol groups into Si–O–Si
linkages, thereby liberating the amino groups from nonspecific interaction with the silanol groups. We prepared different
types of capped amine surface and evaluated the effect of capping on immobilization efficiency by investigating the fluorescence
intensity of Cy3-NHS (N-hydroxysuccinimide) dye that reacted with amino groups. The results indicate that most of the capped amine surfaces resulted
in enhanced efficiency of immobilization of Cy3-NHS compared with the untreated control amine surface. We found a trend that
trialkoxysilanes had greater capping effects on immobilization efficiency than monoalkoxysilanes. It was also found that the
aliphatic chain of alkylsilane, which does not participate in the capping of the silanol, had an important function in enhancing
immobilization efficiency. These results would be useful for preparation of an amine-modified surface platform, with enhanced
immobilization efficiency, which is essential for developing many kinds of biosensors on a silica matrix.
Enhancement of amine funtionality by capping with alkylsilane 相似文献
66.
Anti-selective asymmetric hydrogenation of alpha-amino-beta-keto esters via dynamic kinetic resolution under low hydrogen pressure has been achieved by an easily-handled cationic iridium complex with tetrakis[3,5-bis(trifluoromethyl)phenyl]borate (BARF) as a counterion. 相似文献
67.
Kazuhisa Makino 《Discrete Applied Mathematics》2010,158(18):2024-2030
Gopalan et al. studied in [P. Gopalan, P.G. Kolaitis, E.N. Maneva, C.H. Papadimitriou, The connectivity of Boolean satisfiability: computational and structural dichotomies, in: Proceedings of the 33rd International Colloquium on Automata, Languages and Programming, ICALP 2006, 2006, pp. 346-357] and [P. Gopalan, P.G. Kolaitis, E.N. Maneva, C.H. Papadimitriou, The connectivity of Boolean satisfiability: computational and structural dichotomies, SIAM J. Comput. 38 (6) (2009) 2330-2355] connectivity properties of the solution-space of Boolean formulas, and investigated complexity issues on the connectivity problems in Schaefer’s framework. A set S of logical relations is Schaefer if all relations in S are either bijunctive, Horn, dual Horn, or affine. They first conjectured that the connectivity problem for Schaefer is in P. We disprove their conjecture by showing that there exists a set S of Horn relations such that the connectivity problem for S is -complete. We also investigate a tractable aspect of Horn and dual Horn relations with respect to characteristic sets. 相似文献
68.
Jun Hayashi Nozomu Hashimoto Noriaki Nakatsuka Hirofumi Tsuji Hiroaki Watanabe Hisao Makino Fumiteru Akamatsu 《Proceedings of the Combustion Institute》2013,34(2):2435-2443
Soot formation characteristics of a lab-scale pulverized coal flame were investigated by performing carefully controlled laser diagnostics. The spatial distributions of soot volume fraction and the pulverized coal particles were measured simultaneously by laser induced incandescence (LII) and Mie scattering imaging, respectively. In addition, the radial distributions of the soot volume fraction were compared with the OH radical fluorescence, gas temperature and oxygen concentration obtained in our previous studies [1], [2]. The results indicated that the laser pulse fluence used for LII measurement should be carefully controlled to measure the soot volume fraction in pulverized coal flames. To precisely measure the soot volume fraction in pulverized coal flames using LII, it is necessary to adjust the laser pulse fluence so that it is sufficiently high to heat up all the soot particles to the sublimation temperature but also sufficiently low to avoid including a too large of a change in the morphology of the soot particles and the superposition of the LII signal from the pulverized coal particles on that from the soot particles. It was also found that the radial position of the peak LII signal intensity was located between the positions of the peak Mie scattering signal intensity and peak OH radical signal intensity. The region, in which LII signal, OH radical fluorescence and Mie scattering coexisted, expanded with increasing height above the burner port. It was also found that the soot formation in pulverized coal flames was enhanced at locations where the conditions of high temperature, low oxygen concentration and the existence of pulverized coal particles were satisfied simultaneously. 相似文献
69.
M. Tanaka H. Kohri T. Ohta M. Yosoi M. Fujiwara K. Ueda S. Imoto K. Takamatsu J. -P. Didélez G. Frossati A. de Waard Yu. Kiselev S. Makino H. Fujimura K. Fukushima S. Fukushima H. Kondoh 《Physics of Particles and Nuclei》2013,44(6):959-963
The project in producing the hyperpolarized 3He and 19F are addressed in pursuit of radiation free medical diagnosis. The program for production of the hyperpolarized 3He by the brute force method with the Pomeranchuk cooling and the rapid melting of the solid 3He started a few years ago, and is still on the way, while a new program for production of the hyperpolarized 19F by means of the PHIP (ParaHydrogen Induced Polarization) has just got started. Particular attention is placed upon a new idea of the hyperpolarization catalyst to be used for 19F. 相似文献
70.
Hiroshi Nagai Minami Watanabe Shingo Sato Mioko Kawaguchi Yue-Yun Xiao Kazutaka Hayashi Ryuichi Watanabe Hajime Uchida Masayuki Satake 《Tetrahedron》2019,75(17):2486-2494
The marine cyanobacterium Moorea producens is a rich source of diverse compounds that possess a variety of biological activities. In the present study, eight new aplysiatoxin derivatives, namely 6, 8–13, and 15, along with aplysiatoxin (1), debromoaplysiatoxin (2), 3-methoxyaplysiatoxin (3), anhydroaplysiatoxin (4), anhydrodebromoaplysiatoxin (5), oscillatoxin B2 (7), and 30-methyloscillatoxin D (14) were isolated and identified from the Okinawan M. producens. In cytotoxicity and diatom growth inhibition tests, the fifteen compounds tested (1–15) showed moderate or no activity at a concentration of 10?μg/mL. 相似文献