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991.
Ken-ichi Mawatari Satoshi Mashiko Mitsuo Watanabe Kazuya Nakagomi 《Analytical sciences》2003,19(7):1071-1073
For the determination of khellin in urine and serum, fluorometry using HPLC-postcolumn photoirradiation has been developed. Khellin and visnagin of similar structure were separated on a column of Capcell Pak C8. The mobile phase consisted of 40%(v/v) ethanol containing 75 mmol l(-1) H2O2. The postcolumn reagent, 70 mmol l(-1) KH2PO4-NaOH buffer (pH 12.7) containing 50%(v/v) ethanol, were mixed with the mobile phase, which was irradiated with ultraviolet light to induce fluorescence. The fluorescence was monitored with excitation at 378 nm and emission at 480 nm. The calibration graph for khellin was linear over the range of 65 - 2620 ng ml(-1) using an injection volume of 20 microl. The pretreatment of the urine or serum samples consisted of diluting steps or deproteinizing steps using perchloric acid, respectively. 相似文献
992.
The rotational spectra of the deuterated carbon chain molecules, C3D, C4D, C3HD, and C4HD, have been measured with the Fourier transform microwave (FTMW) spectrometer. The C3D and C4D radicals are produced by discharging the DCCD gas diluted in Ar. On the other hand, the gaseous mixture of HCCH, DCCD, and HCCD diluted in Ar is used for producing C3HD and C4HD. For C3D, the molecular constants are determined from a joint least-squares analysis with the previously published millimeter- and submillimeter-wave data by considering the vibronic interaction between the 2Π ground state and the low-lying 2Σ vibronic state. The molecular constants of C4D are determined by use of the conventional Hamiltonian of the 2Σ radical, while the effective rotational constant and centrifugal distortion constant are derived for C3HD and C4HD. In the present study, the hyperfine interaction constants of the deuterium nuclei in C3D and C4D are determined accurately. In particular, the nuclear quadrupole interaction constant, eQq, of the C3D radical is found to be significantly smaller than those of C2D and C4D, indicating that C3D has a floppy motion of the CCD bending mode due to the large Renner-Teller effect. 相似文献
993.
994.
The kinetics of dissociation and racemization of [Fe(phen)3]2+ have been studied in aqueous methanol solutions containing perchlorate, chloride, and thiocyanate ions. The racemization rate was decreased by ClO?4 and increased by SCN?, while the dissociation rate was decreased by ClO?4 and increased slightly by Cl? and remarkably by SCN?. The effect of anions on the reaction rates became remarkable with the increase in methanol content of the solutions. The results were reasonably explained in terms of ion association. The dissociation rate of the complex ion in the ion-pair increased in the order, ClO?4 < Cl? < SCN?, of associated anions, suggesting the ion-pair interchange mechanism for the dissociation. The ion-association constants were determined to be 11 ± 4, 18 ± 4, and 25 ± 15 (I = 0.1, 25°C) for ClO?4, Cl?, and SCN?, respectively, in 0.64 mole-fraction (0.8 volume-fraction) aqueous methanol. 相似文献
995.
996.
997.
We determine the intermediate mass distribution of the dual resonance pomeron at the one-loop level and we show that the mass distribution obtained is remarkably similar to a suitably defined mass distribution in the dual multiperipheral model. Thus it is suggestive to identify the intermediate states of the dual resonance pomeron with multipheripheral processes. 相似文献
998.
Sayori Nakagawa Satoshi Fukumoto Naohiro Ishii 《Mathematical and Computer Modelling》2003,38(11-13):1357
This paper considers three checkpointing schemes which combine a double modular redundancy and three types of checkpoints: compare-and-store-checkpoint (CSCP), store-checkpoint (SCP), and compare-checkpoint (CCP). An execution time of a task is divided equally into n intervals, and at the end of each interval, a CSCP is always placed. Further, each CSCP interval is also divided equally into m intervals, and at the end of each interval, either CCP or SCP is placed except the last one. Introducing the overheads of comparison, storage, and retry, the mean execution times to complete a task for three schemes are obtained, using the theory of probability. Optimal checkpointing intervals, which minimize the mean times, are analytically derived, and are numerically computed. Three schemes are compared as numerical examples and the best checkpointing scheme is chosen. 相似文献
999.
Mitsuhiro Nakamura Masashi Mamino Shojiro Maki Satoshi Kojima Yoshihiro Ohmiya 《Tetrahedron letters》2005,46(1):53-56
A series of Latia luciferin analogues having methyl-substituted phenyl groups instead of the natural 2,6,6-trimethylhexene ring was synthesized and their bioluminescence activity were measured. The Latia luciferase was found to be able to moderately recognize the appropriately methyl-substituted phenyl analogues with the same light production kinetics as that of natural luciferin. 相似文献
1000.
T. Fukui introduced an invariant for the blow-analytic equivalence of real singularities. For a nondegenerate analytic function (germ) f, he discovered a formula for computing the one-dimensional invariant, denoted by A(f) := A
1(f). We find a formula for A(f) for any f (real or complex, degenerate or not). We then define, and characterise, various notions of stability of A(f), using the formula. For real analytic f, the Fukui invariant with sign is defined, and computed by a similar formula. In the case where f is an analytic function of two complex variables, A(f) can also be computed using the tree-model of f. 相似文献