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991.
Kishikawa N Hamachi C Imamura Y Ohba Y Nakashima K Tagawa Y Kuroda N 《Analytical and bioanalytical chemistry》2006,386(3):719-724
A simultaneous method for the determination of haloperidol (HP) and its metabolite, reduced haloperidol (RHP), in human serum was developed by means of high-performance liquid chromatography (HPLC) with fluorescence detection. Suzuki coupling reaction with a fluorescent arylboronic acid, 4-(4,5-diphenyl-1H-imidazol-2-yl)phenylboronic acid (DPA), was employed to convert HP and RHP into highly fluorescent compounds. HP and RHP were extracted from human serum by liquid-liquid extraction with a mixture of n-hexane and isoamyl alcohol (99:1, v/v) and subsequently labeled by reaction with DPA. Separation of DPA derivatives of HP and RHP was performed on a silica column with a mixture of acetonitrile and H(2)O (90:10, v/v) containing triethylamine and acetic acid as a mobile phase. The proposed method allowed sensitive detection of HP and RHP in human serum with a detection limit (at a signal to noise ratio of 3) of 0.22 and 0.20 ng/mL, respectively. The applicability of the method for therapeutic drug monitoring (TDM) was demonstrated by analyzing human serum samples from schizophrenic patients receiving HP. 相似文献
992.
Kazutaka Kuroda Hideo Nagai 《Stochastics An International Journal of Probability and Stochastic Processes》2013,85(3-4):309-331
We consider a continuous time portfolio optimization problems on an infinite time horizon for a factor model, recently treated by Bielecki and Pliska ["Risk-sensitive dynamic asset management", Appl. Math. Optim. , 39 (1990) 337-360], where the mean returns of individual securities or asset categories are explicitly affected by economic factors. The factors are assumed to be Gaussian processes. We see new features in constructing optimal strategies for risk-sensitive criteria of the portfolio optimization on an infinite time horizon, which are obtained from the solutions of matrix Riccati equations. 相似文献
993.
Amponsaa-Karikari A Kishikawa N Ohyama K Nakashima K Kuroda N 《Biomedical chromatography : BMC》2009,23(1):101-106
A sensitive, selective and reliable method has been developed and validated for the determination of halofantrine and its metabolite desbutylhalofantrine in rat plasma using 9,10-diphenylanthracene as an internal standard. The method is based on peroxyoxalate chemiluminescence detection of hydrogen peroxide produced from fused aromatic rings in the structures of halofantrine and desbutylhalofantrine upon UV irradiation. Using spiked rat plasma, good linear relationships were obtained for both halofantrine and desbutylhalofantrine between peak height ratios (vs internal standard) and their corresponding concentrations over a range of 0.01-0.8 microg/mL with correlation coefficients of at least 0.997. The detection limits at signal-to-noise ratio of 3 using 0.2 mL of rat plasma were 1.5 and 1.4 ng/mL for halofantrine and desbutylhalofantrine, respectively. Relative standard deviations (n = 3) intra- and inter-day were between 0.5 and 5.4% for all the studied concentrations. Using this method with simple sample treatment, halofantrine and desbutylhalofantrine in rat plasma could be precisely determined without interference from endogenous substances. The method was successfully applied to the measurement of the time courses of plasma halofantrine concentration after oral administration of the drug (7 mg/kg) to rats. 相似文献
994.
The sum of the rate constants for solvolysis and scrambling of carbon bridging and nonbridging oxygen-18 at 4-MeC(6)H(4)CH(CF(3))OS((18)O(2))Tos in 50/50 (v/v) trifluoroethanol/water, (k(solv) + k(iso)) = 5.4 × 10(-6) s(-1), is 50% larger than k(solv) = 3.6 × 10(-6) for the simple solvolysis reaction of the sulfonate ester. This shows that the ion pair intermediate of solvolysis undergoes significant internal return to form reactant. These data give a value of k(-1) = 1.7 × 10(10) s(-1) for internal return of the carbocation-anion pair to the substrate. This rate constant is larger than the value of k(-1) = 7 × 10(9) s(-1) reported for internal return of an ion pair between the 1-(4-methylphenyl)ethyl carbocation and pentafluorobenzoate anion to the neutral ester (4-MeC(6)H(4)CH(CH(3))O(2)CC(6)F(5)) in the same solvent. The partitioning of ion pairs to the 1-(4-methylphenyl)ethyl carbocation and to the highly destabilized 1-(4-methylphenyl)2,2,2-trifluoroethyl carbocation is compared and contrasted. 相似文献
995.
We have studied micro-photoluminescence spectra of a self-assembled single GaAs quantum dot under 8 K. With strong pulsed excitation, the micro-photoluminescence spectrum shows bright emission lines originated from an exciton, a positively charged exciton, and a biexciton, together with weak lower energy emissions reflecting multi-excitonic structures with more carriers. We have identified the origins of these weak emission lines, and showed the existence of charged biexciton states, through single photon correlation measurements and excitation power dependence of the photoluminescence intensity. In addition, investigating the radiative recombination process of the charged biexciton, we have determined the electron–hole exchange energy in the GaAs quantum dot. 相似文献
996.
The generation of lower (third) and higher harmonics of femtosecond laser radiation in plasmas produced by laser ablation
of different targets with a small atomic number Z (B, Be, Li) has been investigated. The high (10−3) efficiency of third-harmonic generation was observed in plasma produced on the boron surface. Efficient third-harmonic generation
was also observed in beryllium plasma using femtosecond pulses of Ti:sapphire laser radiation (λ = 790 nm) and its second
harmonic (395 nm). We could tune the higher harmonics generation spectrum by tuning the crystal converter when using 395-nm
radiation to be converted. It is shown that, in plasmas formed on targets with small Z, the conversion efficiency and limiting generated harmonic order depend on the delay between the ablation pulse and the pulse
to be converted. 相似文献
997.
T. Kihira S. Tanaka M. Yamagiwa Y. Ogawa F. Minami N. Koguchi 《Journal of luminescence》2008,128(5-6):800-802
Single-photon emitters and detectors are key devices for realizing secure communications by single-photon-based cryptography and single-photon-based quantum computing. For the establishment of these technologies, we need to understand the electronic structures of single and multiple excitons. Therefore, we have studied their emissions via the micro-photoluminescence (μ-PL) spectra of strain-free GaAs/AlGaAs single quantum dots, using excitation power dependence, time-resolved, and single-photon correlation measurements. Under pulsed excitation, we observed clear photon antibunching and bunching by auto- and cross-correlation measurements. From these results, we found that the emission peaks observed in the μ-PL spectra originated from exciton, charged exciton, and biexciton states. 相似文献
998.
Ultrasonic generators are used as emulsifiers and efficient alternative initiators in polymerization processes. In this study, the effects of reactor's position on the emulsion polymerization of styrene under indirect ultrasonic irradiation were investigated, along with the effects of reactor's position on chemical and physical degradation. Both polymer yield and molecular weight were influenced by the position of the reactor. The ultrasonic irradiation could be divided into three stages, and the molecular weight of the polymer was influenced by polymerization and degradation processes. It was found that the extent of radical generation estimated by KI oxidation dosimetry and the shock wave index obtained from studies of degradation of standard polymer were useful for controlling the characteristics of the polymer generated. 相似文献
999.
Keiichi Minami Fuminori Mizuno Akitoshi Hayashi Masahiro Tatsumisago 《Journal of Non》2008,354(2-9):370-373
The 70Li2S · (30 ? x)P2S5 · xP2O5 (mol%) oxysulfide glasses were prepared by the melt quenching method. The glasses were prepared in the composition range 0 ≦ x ≦ 10. The glass–ceramics were prepared by heating the glasses over crystallization temperatures. The POnS3?n (n = 1–3) oxysulfide units were produced in the glasses and glass–ceramics by partial substituting P2O5 for P2S5. In particular, the P2OS64? unit would be produced by substituting a small amount of P2O5 for P2S5. The oxygen atoms were incorporated into the Li7P3S11 crystal structure because the diffraction peaks of the oxysulfide glass–ceramic shifted to the higher angle side. The glass–ceramic with 3 mol% of P2O5 exhibited the highest conductivity of 3.0 × 10?3 S cm?1 and the lowest activation energy for conduction of 16 kJ mol?1. The P2OS64? dimer units in the oxygen-incorporated Li7P3S11 crystal would improve conductive behavior of the Li2S–P2S5 glass–ceramics. 相似文献
1000.
MA Yue S.Ajimura K.Aoki M.Dairaku Fu Yuan-yong H.Fujioka T.Fukuda K.Futatsugawa K.Hosomi W.Imoto M.Kawai Y.Kakiguchi S.Kinoshita T.Koike N.Maruyama M.Mimori S.Minami Y.Miura K.Miwa Y.Miyagi T.Nagae D.Nakajima H.Noumi K.S hirotori T.Suzuki T.Takahashi T.N.Takahashi K.Tanida N.Terada A.Toyoda K.Tsukada M.Ukai ZHOU Shu-hua H.Tamura 《原子核物理评论》2009,26(Z1)
In this proceeding,we will first outline the experimental setup and main results of the most recent hypernuclear γ-ray spectroscopy experiment (KEK-E566) performed at KEK-PS K6 beam line.The main feature and characteristics of this type of research will he emphasised.After that,the approved experimental proposal (E13) at J-PARC facility will be introduced briefly. 相似文献