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81.
Lithuanian Mathematical Journal - We survey some recent developments in the analytic theory of multiple Dirichlet series with arithmetical coefficients as numerators. 相似文献
82.
ω-(Phenylthio)-ω-chloroalkyl acetates were allowed to react with MeLi (3.2 equiv) to give 2-(phenylthio) cycloalkanols which were produced by the regioselective intramolecular insertion by (phenylthio) carbenes. 相似文献
83.
Kiyoshi Fuda Kohji Kishio Shigeru Yamauchi Kazuo Fueki 《Journal of Physics and Chemistry of Solids》1985,46(10):1141-1146
The 17O NMR measurement was made to elucidate the microscopic nature of vacancy motion in Y2O3-doped CeO2. Spin-lattice relaxation rate, T?11, spin-spin relaxation rate, T?12, and resonance intensity were measured at v0 = 8.13 MHz as a function of temperature [385 < T (K) < 1110] and composition []. The static electric field gradient associated with lattice defects resulted in the composition dependences of the line width and the intensity. In low dopant concentrations, doubly peaked temperature dependence of T?11 was found, while a single and asymmetric peak was observed in high concentrations. T?11 of 4.0 and 6.0 doped samples were analyzed using a barrier height distribution model for the oxygen vacancy jump. The mean value of the activation energy was found to increase with the Y2O3 concentration. 相似文献
84.
85.
Fluorescent nucleosides with modified nucleobases are useful tools for detecting nucleic acids and probing their structures and functions. Nucleobases are suitable for modification because 1) intrinsically light-absorbing nucleobases can be converted to fluorescent chromophores by simple chemical modification, 2) attaching substituents to nucleobases at appropriately selected positions does not inhibit base pairing or duplex formation, and 3) duplex formation and protein interactions affect the environment of nucleobases, causing changes in their fluorescence intensities and/or wavelengths. This review summarizes recent fluorescent nucleosides and their photophysical properties, such as absorption wavelength, emission wavelength, and fluorescence quantum yield together with their solvent dependency. 相似文献
86.
For 1/2<<1 fixed, letE
(T) denote the error term in the asymptotic formula for
. We obtain some new bounds forE
(T), and an _-result which is the analogue of the strongest _-result in the classical Dirichlet divisor problem. 相似文献
87.
Takeshi Sasami Yoko Odawara Akihiro Ohkubo Mitsuo Sekine Kohji Seio 《Tetrahedron letters》2007,48(30):5325-5329
2-N-Carbamoyldeoxyguanosine and its derivatives were synthesized and incorporated into ODNs. The Tm analyses revealed higher selective base recognition ability of 2-N-carbamoylguanine than that of guanine. The new guanine analog must be useful for the development of functional oligodeoxynucleotides capable of precise base recognition. 相似文献
88.
To not only improve the inherently poor stability of the phenylboranylidene group as a protecting group of the 2',3'-cis-diol function of ribonucleosides but also introduce a colorimetrically detectable function into its mother structure, various 2-[(dialkylamino)methyl]phenylboronic acid derivatives having a [(4,4'-dimethoxytrityl)oxy]methyl group were synthesized. The reaction of uridine with these substituted phenylboronic acid derivatives gave the corresponding 2',3'-O-phenylboranylideneuridine derivatives. The stability of these phenylboranylidene groups was examined. As a result, it was shown that the steric hindrance around the amino group greatly influenced the stability of the 2-substituted phenylboranylidene groups. The 2-aminomethyl-5-[[(4,4'-dimethoxytrityl)oxy]methyl]phenylboranylidene group was the most stable. Its 2-dimethylamino counterpart, the 2-[(dimethylamino)methyl]-5-[[(4,4'-dimethoxytrityl)oxy]methyl]phenylboranylidene group, was the second most stable. When the most and second stable protecting groups were applied to the synthesis of m(2)(2,2)G(5)(')ppT on controlled pore glass, the second stable protecting group showed the best result. The use of this DMTr-containing protecting group enabled us to estimate colorimetrically the amount of the m(2)(2,2)G residue that was incorporated into the reactive site of the pT-loaded CPG resin. 相似文献
89.
Kazumasa Ibi Kohji Kawai Shinzi Kato Prof. Dr. Fumio Ando Jugo Koketsu 《无机化学与普通化学杂志》2007,633(4):621-624
A series of O‐triorganosilyl carbamoselenoates were isolated in good yields from the reaction of sodium or potassium carbamoselenoates with triorganosilyl chlorides. The O‐silyl carbamoselenoates readily reacted with RbF and CsF and with organo‐germanium, ‐tin, and ‐lead halides and gave the corresponding heavy alkali metal and Se‐substituted Group 14 organometal and carbamoselenoates in moderate to good yields. 相似文献
90.
Kiyoshi Shibata Hiroshi Kimura Akira Tsuchida Tsuneo Okubo Shohei Sato Kohji Yoshinaga 《Colloid and polymer science》2006,284(4):372-379
Electro-optic responses of colloidal crystals consist of poly(maleic anhydride-co-styrene)-modified silica spheres (P(MA-ST)/SiO2) in acetonitrile and the crystals immobilized with a gelator, N-benzyloxycarbonyl-L-isoleucilaminooctadecane (Z-L-Ile-C-18), are studied by reflected-light intensity measurements and time-resolved reflection spectroscopy. Application of
an alternating electric field deforms P(MA-ST)/SiO2 crystal lattices reversibly. The response waveforms from the crystals are dependent on the frequency and strength of the
applied electric field; similar dependencies have been qualitatively observed for the colloidal crystals consisting of polystyrene
or silica spheres in aqueous media in our previous studies. Both gelated and ungelated P(MA-ST)/SiO2 crystals change the reflection intensity, however, the amplitude is larger for the latter. The small response for the gelated
P(MA-ST)/SiO2 crystals is attributed to the higher elastic modulus (G). The G value of the gelated P(MA-ST)/SiO2 crystals in acetonitrile is estimated from the change in the inter-sphere distance to be 8.0 Pa, which is about 2.3 and 2.4
times larger than that for ungelated P(MA-ST)/SiO2 crystals in acetonitrile and colloidal silica crystals in aqueous media, respectively. 相似文献