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41.
We investigated simultaneous determination of haloperidol (HAL), its three metabolites [reduced HAL (R-HAL), 3-(4-fluorobenzoyl)propionic acid (FBPA) and 4-(4-chlorophenyl)-4-hydroxypiperidine (CPHP)] and two related compounds [spiperone (SPI) and droperidol (DRO)] in phosphate-buffered saline using high-performance liquid chromatography (HPLC) coupled with dual ultraviolet detection (220 and 250 nm). Retention times of HAL, R-HAL, FBPA, CPHP, SPI and DRO were 16.8, 11.8, 10.2, 4.1, 12.6 and 8.3 min, respectively. Their lower limits of detection were 7.5, 14, 4.5, 12, 10 and 20 ng/mL in the same order. The coefficients of variation for their intra- and inter-day assays were less than 7.8 and 9.4%, respectively. Of the other centrally acting drugs, only amoxapine interfered with the peak of DRO. Using our procedure, the binding study of tested compounds to synthetic melanin, human serum albumin and alpha1-acid glycoprotein was performed by determining the unbound concentration to total concentration ratio. These results indicated that simultaneous assay of HAL, R-HAL, FBPA, CPHP, SPI and DRO in phosphate-buffered saline by HPLC equipped with dual ultraviolet detection is simple, sensitive and reproducible. Also, our assay system can be applied to the binding study of these compounds to synthetic melanin, human serum albumin and alpha1-acid glycoprotein. 相似文献
42.
The synthesis and properties of a new class of heterocyclic compounds 5–8 derived from 2-aminobenzo-phenone and diethyl 2,5-dioxo-1,4-cyclohexanedicarboxylate were investigated. 相似文献
43.
Both the enantiomers of sclerosporin and sclerosporal were synthesized from (-)-carvone. (4R,9R,10S)-(+)-Sclerosporin and (4R,9R,10S)-(-)-sclerosporal were identified as the natural enantiomers by a comparison of their CD-spectra. An intramolecular Diels-Alder route was proved to be an efficient method of preparing sufficient amounts of (+)- for the biological study. 相似文献
44.
Experimental visualization for ionic wind motion originated from DC corona discharges in a needle-plate electrode system has
been investigated. A vapor-phase biacetyl tracer with laser-induced phosphorescence emission is used for optically characterizing
the ionic wind profile. The ionic wind blows the excited biacetyl molecules away in continuing the visible phosphorescence
emission for a long radiative lifetime. The captured image with elapsing time from the excitation presents the shifting location
of radiative tracer along the ionic wind direction. The experimental results show the ionic wind profile enhanced in the electric
field direction corresponding to the corona discharge progress. Especially, the ionic wind near an initiating point of corona
discharges is focused as an advantage of this optical technique. The ionic wind velocity along the electrode axis can be obtained
at the location close enough to the corona discharge initiation point, and the velocity at 0.5 mm from the discharge point
is figured out as 9.3 to 19.2 m/s under the condition of the EHD Reynolds number of 0.95×103 to 2.1×103. 相似文献
45.
S.?OrimoEmail author Y.?Nakamori G.?Kitahara K.?Miwa N.?Ohba T.?Noritake S.?Towata 《Applied Physics A: Materials Science & Processing》2004,79(7):1765-1767
First-principles calculations have been applied to lithium amide, LiNH2, to characterize its electronic structure. Based on the theoretical study, we predict that an effective method for destabilizing LiNH2 is to partially substitute Li by other elements with larger electronegativity, such as Mg. Experimental results on dehydriding reactions of LiNH2 with/without the partial Mg substitutions suggest the destabilization of the samples with increasing Mg concentrations, which is in good agreement with our prediction. The dehydriding reactions of LiNH2 with partial Mg substitutions are useful as hydrogen-storage materials for fuel-cell applications. PACS 81.05.Zx; 71.20.Ps; 82.30.-b 相似文献
46.
Scattering of particle-like patterns in dissipative systems is studied, especially we focus on the issue how the input-output relation is controlled at a head-on collision where traveling pulses or spots interact strongly. It remains an open problem due to the large deformation of patterns at a colliding point. We found that a special type of unstable steady or time-periodic solutions called scattors and their stable and unstable manifolds direct the traffic flow of orbits. Such scattors are in general highly unstable even in the one-dimensional case which causes a variety of input-output relations through the scattering process. We illustrate the ubiquity of scattors by using the complex Ginzburg-Landau equation, the Gray-Scott model, and a three-component reaction diffusion model arising in gas-discharge phenomena. 相似文献
47.
M. Aoki K. Miwa T. Noritake G. Kitahara Y. Nakamori S. Orimo S. Towata 《Applied Physics A: Materials Science & Processing》2005,80(7):1409-1412
It was revealed that LiBH4 is destabilized by mixing with LiNH2 and the mixture desorbs a large amount of hydrogen. First-principles calculations predicted that the enthalpies of dehydrogenation for LiBH4 alone and the mixture of LiBH4+2LiNH2 are 75 kJ/molH2 and 23 kJ/molH2, respectively. Motivated by this prediction, we experimentally examined the dehydrogenation properties for LiBH4 and the mixture under hydrogen pressure. The amounts of desorbed hydrogen from LiBH4 and the mixture at 703 K and 522 K were 10.6 mass% and 7.8 mass%, respectively. The dehydrogenation pressure of the mixture was much higher than that of LiBH4 alone, although the mixture was measured at approximately 180 K lower temperature. This result suggests that the mixture is much unstable as compared with LiBH4 alone.PACS 81.05.Zx; 71.20.Ps; 82.30.-b 相似文献
48.
Photochemical efficiency of o-quinodimethane (3) ring closure at room temperature was determined by using a time-delayed, two-color photolysis technique. o-Quinodimethane (3) was generated by the photolysis of 1,2-bis[(phenylseleno)methyl]benzene (1) by a KrF (248 nm) laser pulse and thus-generated 3 was photolyzed by a subsequent XeCl (308 nm)/XeF (351 nm) laser pulse with varying delay time of 0 to 3 s. The time profile of 3 was monitored by the chemical analyses of benzocyclobutene (5) (a photochemical product of 3), which was formed by a one-photon process, and the spiro dimer of 3 (4) (a thermal product of 3) in the two-color photolysis experiments. The time profile of 3 followed a second-order decay kinetics. The photochemical efficiency was obtained by the analysis of the delay-time dependence of the product yields; those of the consumption of 3 and the conversion 3-->5 by a single pulse of the excimer laser were 81% and 5.7% for the XeCl laser, and 73% and 2.3% for the XeF laser. This difference was attributed to the different excited states involved in the photolysis. In contrast to the photolysis of 3 in argon or rigid organic matrixes, it was revealed that photochemical conversion 3-->5 was not the main path in the solutions, and intermolecular reactions predominated. 相似文献
49.
50.