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831.
Santa T Al-Dirbashi OY Ichibangase T Fukushima T Rashed MS Funatsu T Imai K 《Biomedical chromatography : BMC》2007,21(11):1207-1213
The applicability of benzofurazan derivatization regents to carboxylic acids analysis in LC/ESI-MS/MS (high-performance liquid chromatography/electrospray ionization tandem mass spectrometry) was examined. The product ion spectra of DAABD-AE {4-[2-(N,N-dimethylamino)ethylaminosulfonyl]-7-(2-aminoethylamino)-2,1,3-benzoxadiazole}, DAABD-PZ {4-[2-(N,N-dimethylamino)ethylaminosulfonyl]-7-N-piperazino-2,1,3-benzoxadiazole}, DAABD-PiCZ {4-[4-carbazoylpiperidin-1-yl]-7-[2-(N,N-dimethylamino)ethylaminosulfonyl]-2,1,3-benzoxadiazole}, DAABD-ProCZ {4-[2-carbazoylpyrrolidin-1-yl]-7-[2-(N,N-dimethylamino) ethylaminosulfonyl]-2,1,3-benzoxadiazole} and DAABD-Apy {4-[2-(N,N-dimethylamino)ethylaminosulfonyl]-7-(3-aminopyrrolidin-1-yl)-2,1,3-benzoxadiazole}, and their acetylated compounds were obtained. An intense fragment ion at m/z 151 corresponding to (dimethylamino)ethylaminosulfonyl moiety was observed in each spectra, suggesting that these reagents were suitable for ESI-MS/MS analysis. DAABD-AE, DAABD-APy and DAABD-PZ were applied to the analysis of octanoic acid and it was found that DAABD-AE and DAABD-APy gave high signal intensity suitable for LC/ESI-MS/MS. 相似文献
832.
We consider a random walk in random environment with random holding times, that is, the random walk jumping to one of its nearest neighbors with some transition probability after a random holding time. Both the transition probabilities and the laws of the holding times are randomly distributed over the integer lattice. Our main result is a quenched large deviation principle for the position of the random walk. The rate function is given by the Legendre transform of the so-called Lyapunov exponents for the Laplace transform of the first passage time. By using this representation, we derive some asymptotics of the rate function in some special cases. 相似文献
833.
Koichi Nabetani Paul Tseng Masao Fukushima 《Computational Optimization and Applications》2011,48(3):423-452
We consider the generalized Nash equilibrium problem (GNEP), in which each player’s strategy set may depend on the rivals’
strategies through shared constraints. A practical approach to solving this problem that has received increasing attention
lately entails solving a related variational inequality (VI). From the viewpoint of game theory, it is important to find as
many GNEs as possible, if not all of them. We propose two types of parametrized VIs related to the GNEP, one price-directed
and the other resource-directed. We show that these parametrized VIs inherit the monotonicity properties of the original VI
and, under mild constraint qualifications, their solutions yield all GNEs. We propose strategies to sample in the parameter
spaces and show, through numerical experiments on benchmark examples, that the GNEs found by the parametrized VI approaches
are widely distributed over the GNE set. 相似文献
834.
The parabolic Anderson problem with a random potential obtained by attaching a long tailed potential around a randomly perturbed lattice is studied. The moment asymptotics of the total mass of the solution is derived. The results show that the total mass of the solution concentrates on a small set in the space of configuration. 相似文献
835.
Saito T Fukushima T Yui Y Miyazaki S Nakamoto A Namera A Inokuchi S 《Analytical and bioanalytical chemistry》2011,400(1):25-31
We present a method based on monolitic spin column extraction and gas chromatography–mass spectrometry as an analytical method
for screening diquat (DQ), paraquat (PQ), and fenitrothion in serum and urine. This method is useful for clinical and forensic
toxicological analyses. Recovery of DQ, PQ, and fenitrothion from serum and urine, spiked at concentrations between 0.1, 2.5,
20, and 45 μg/ml, ranged from 51.3% to 106.1%. Relative standard deviation percentages were between 3.3% and 14.8%. Detection
and quantitation limits for serum and urine were 0.025 and 0.05 μg/ml, respectively, for DQ, 0.1 and 0.1 μg/ml, respectively,
for PQ, and 0.025 and 0.05 μg/ml, respectively, for fenitrothion. Therefore, these compounds can be detected and quantified
in the case of acute poisoning. 相似文献
836.
Matano Y Saito A Fukushima T Tokudome Y Suzuki F Sakamaki D Kaji H Ito A Tanaka K Imahori H 《Angewandte Chemie (International ed. in English)》2011,50(35):8016-8020
A profusion of phospholes: Diacenaphtho[1,2-b:1',2'-d]phospholes, a new class of arene-fused phosphole π-systems, were synthesized and their structural and electrochemical properties studied. The P-sulfide derivative has a high electron-transporting ability (μ(E) =2.4×10(-3) cm(2) V(-1) s(-1)) in a vacuum-deposited film. 相似文献
837.
Shigeru Oae Koich Shinhama Daikich Fukushima Yong H. Kim 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-2)
Abstract Symmetrical disulfides were known to be oxidized with excess N2O4 to the corresponding sulfonic anhydride in good yields. We have found that the oxidation of methyl phenyl disufide or an intermediate, phenyl methanethiolsulfinate undergoes via forming the unstable intermediate, i.e. the thionitrite, which are derived by the cleavage of sulfur-sulfur bond of the subsrates. The oxidation products were symmetrical disulfides, thiolsulfonates, and sulfonic acids which were undoubtedly derived from the scission of sulfur-sulfur bond. 相似文献
838.
839.