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131.
We have developed a simple and practical procedure for a direct reductive conversion from a variety of tertiary amides to the corresponding tertiary amines using an InBr3/Et3SiH reducing system. This reducing system can be applied to the reduction of a secondary amide and provides a more efficient alternative to conventional methods that use aluminum and boron hydrides. 相似文献
132.
Saito H Shirai T Kudo H Mitsubayashi K 《Analytical and bioanalytical chemistry》2008,391(4):1263-1268
A bioelectronic sensor for triethylamine (TEA) was developed with a flavin-containing monooxygenase type 3 (FMO-3). The TEA
biosensor consisted of a Clark-type dissolved-oxygen electrode and an FMO-3 immobilized membrane. The FMO-3 solution was mixed
with a poly(vinyl alcohol) containing stilbazolium groups (PVA-SbQ), coated on to the dialysis membrane, and the membrane
was irradiated with a fluorescent light to immobilize the enzyme. In order to amplify the biosensor output, a substrate regeneration
cycle, obtained by coupling the monooxygenase with l-ascorbic acid (AsA) as reducing reagent system, was applied. The effect of pH on the determination of TEA was studied. The
maximum response was achieved at pH >9.0. A drop of the phosphate buffer solution with the AsA was put on the sensing area
of the oxygen electrode, and the FMO-3 immobilized membrane was placed on the oxygen electrode and covered with a supporting
Nylon mesh net which was secured with a silicone O-ring. A measurement system for TEA solution was constructed using the FMO-3
biosensor, a personal computer, a computer-controlled potentiostat, and an A/D converter. The FMO-3 biosensor was used to
measure TEA solution from 0.5 to 4.0 mmol L−1 with 10.0 mmol L−1 AsA. The biosensor also had good reproducibility, for example a 6.31% coefficient of variation for five measurements, and
the output current was maintained over a few hours. In order to improve the selectivity of the TEA biosensor, three type of
biosensor with FMO isomer types 1, 3, and 5 were constructed and used to measure nitrogen and sulfur compounds. The outputs
of the isomer biosensors indicated individual patterns for each sample solution. The selectivity of TEA biosensor would be
improved, and determination of sulfur and nitrogen compounds would be possible, by using the different output of biosensors
prepared from different FMO isomers. 相似文献
133.
Kohji Matsumoto Takashi Nakamura Hirofumi Tsumura 《Proceedings of the American Mathematical Society》2008,136(6):2135-2145
In this paper, we prove the existence of meromorphic continuation of certain triple zeta-functions of Lerch's type. Based on this result, we prove some functional relations for triple zeta and -functions of the Mordell-Tornheim type. Using these functional relations, we prove new explicit evaluation formulas for special values of these functions. These can be regarded as triple analogues of known results for double zeta and -functions.
134.
Ohkubo A Nishino Y Yokouchi A Ito Y Noma Y Kakishima Y Masaki Y Tsunoda H Seio K Sekine M 《Chemical communications (Cambridge, England)》2011,47(46):12556-12558
In this study, it was found that the arrangement of consecutive thiocarbonyl groups of s(2)T and m(5)s(2)C remarkably stabilized the pre-protonated form of the triplex, and that the stabilization of the pre-protonated form increased the pKa value of a cytosine derivative in the triplex. 相似文献
135.
Suzuki H Murou M Kitano H Ohno K Saruwatari Y 《Colloids and surfaces. B, Biointerfaces》2011,84(1):111-116
Silica particles (SiP) were modified with 2-bromoisobutyryl group-carrying silane coupling reagent, and a polymer brush of carboxymethylbetaine, poly[1-carboxy-N,N-dimethyl-N-(2'-methacryloyloxyethyl)methanaminium inner salt] (PolyCMB), was introduced onto surface of the particles using surface-initiated atom transfer radical polymerization (ATRP). After purification by simple ultrafiltration, the layer of the PolyCMB brush-carrying silica particle (SiP-PolyCMB) in aqueous medium showed a clear iridescence at the bottom of a quartz cell upon a slow sedimentation, indicating the formation of colloidal crystals due to both electrostatic and steric repulsion between the particles. The peak of the reflection spectra gradually shifted to a smaller wavelength region due to the formation of more densely packed ordered structure of the SiP-PolyCMB. Moreover, SiP-PolyCMBs dispersed in water showed neither salt- nor freeze-thaw cycle-induced coagulation, and were resistant against the non-specific adsorption of proteins such as bovine serum albumin and egg white lysozyme, which is in contrast with the noticeable adsorption of the proteins to the bare silica particles. 相似文献
136.
Kohji Yanagawa 《代数通讯》2013,41(8):3122-3146
137.
138.
Tomonori Ito Tomoyuki Nakamura Toru Akiyama Kohji Nakamura 《Applied Surface Science》2008,254(23):7659-7662
Surface phase diagrams of GaN(0 0 0 1)-(2 × 2) and pseudo-(1 × 1) surfaces are systematically investigated by using our ab initio-based approach. The phase diagrams are obtained as functions of temperature T and Ga beam equivalent pressure pGa by comparing chemical potentials of Ga atom in the vapor phase with that on the surface. The calculated results imply that the (2 × 2) surface is stable in the temperature range of 700-1000 K at 10−8 Torr and 900-1400 K at 10−2 Torr. This is consistent with experimental stable temperature range for the (2 × 2). On the other hand, the pseudo-(1 × 1) phase is stable in the temperature range less than 700 K at 10−8 Torr and less than 1000 K at 10−2 Torr. Furthermore, the stable region of the pseudo-(1 × 1) phase almost coincides with that of the (2 × 2) with excess Ga adatom. This suggests that Ga adsorption or desorption during GaN MBE growth can easily change the pseudo-(1 × 1) to the (2 × 2) with Ga adatom and vice versa. 相似文献
139.
Tomoki Yamashita Kosuke Sano Toru Akiyama Kohji Nakamura Tomonori Ito 《Applied Surface Science》2008,254(23):7668-7671
Structural trends in group III-V semiconductor nanowires (NWs) are systematically investigated based on Monte-Carlo simulations using our empirical potential calculations. The calculated NW stacking sequences for the selective area growth demonstrate that the averaged periodicity between wurtzite segments, which is independent of the NW size, decreases with increasing ionicity of semiconductors fi. It is also found that the periodicity is affected by the nucleus size of NWs: The calculated periodicity in InP (InAs) NWs with the nucleus size consisting of ∼ 10 atoms are 0.76 (0.86) nm, reasonably consistent with the experimentally reported one. On the other hand, the nucleus size to reproduce the experimentally reported periodicity in GaAs NWs is estimated to be more than 70 atoms. These results thus imply that the nucleus size as well as fi is of importance in determining the averaged periodicity between wurtzite segments. 相似文献
140.
Masataka Chida Hidenori Katsurada Kohji Matsumoto 《Abhandlungen aus dem Mathematischen Seminar der Universit?t Hamburg》2014,84(1):31-47
We prove a formula of Petersson’s type for Fourier coefficients of Siegel cusp forms of degree 2 with respect to congruence subgroups, and as a corollary, show upper bound estimates of individual Fourier coefficients. The method in this paper is essentially a generalization of Kitaoka’s previous work which studied the full modular case, but some modification is necessary to obtain estimates which are sharp with respect to the level aspect. 相似文献