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71.
Chetiyanukornkul T Toriba A Kizu R Makino T Nakazawa H Hayakaw K 《Journal of chromatography. A》2002,961(1):107-112
A high-performance liquid chromatographic method has been developed for the quantification of 1-hydroxypyrene (1-OHP) in human urine using deuterated 1-hydroxypyrene ([2H9]1-OHP) as an internal standard with fluorescence detection. [2H9]1-OHP was prepared enzymatically from deuterated pyrene ([2H10]Pyr) with cytochrome P450 1A1. It eluted immediately prior to non-deuterated 1-OHP on alkylamide-type reversed-phase columns and had nearly the same fluorescence characteristics as non-deuterated 1-OHP. The detection limit was 0.1 microg/L and the calibration range was from 1 to 100 nmol/L. Urine sample treatment involved enzymatic hydrolysis followed by solid-phase extraction using Sep-Pak C18 cartridges. The proposed method was used to determine urinary 1-OHP in smokers and non-smokers. 相似文献
72.
Ryoichi Shimizu 《Annals of the Institute of Statistical Mathematics》1986,38(1):195-204
Summary LetX be a positive random variable with the survival function
and the densityf. LetX have the moments μ=E(X) and μ2=E(X
2) and put ε=|1-μ2/2μ2|. Put
and
. It is proved that the following inequalities hold:
, for allx>0, ifq(x) is monotone and that
, ifq
1
(x) is monotone. It is also shown that Brown's inequality
which holds wheneverq
1
(x) is increasing is not valid in general whenq
1 is decreasing.
The Institute of Statistical Mathematics 相似文献
73.
Cyclotrimerization of two different, unsymmetrical acetylenes and p-toluenesulfonylnitrile with a divalent titanium alkoxide reagent, Ti(O-i-Pr)4/2 i-PrMgCl, yielded single pyridyltitanium compounds in a highly selective manner. These metalated pyridines were confirmed by deuteriolysis to give the corresponding deuterated pyridines and underwent iodinolysis and copper-catalyzed alkylation to demonstrate their synthetic utility. Alternatively, a different type of cyclotrimerization of an alkynamide, terminal acetylenes, and alpha-alkoxynitriles mediated by the same titanium(II) alkoxide again proceeded in a highly selective manner to give single pyridines having a titanated side chain. 相似文献
74.
Ryoichi Hirayama Masahiro Kawase Tetsutaro Kimachi Kiyoshi Tanaka Fumio Yoneda 《Journal of heterocyclic chemistry》1989,26(5):1255-1259
Various 8-hydroxy-5-deazaflavin derivatives were synthesized as the model compounds of coenzyme F420-These compounds oxidized benzylamine to benzaldehyde more efficiently than the corresponding 8-unsubstituted 5-deazaflavins. 相似文献
75.
Thermomechanical analysis of a polymer dispersed liquid crystal containing a thermoplastic elastomer
Hideyuki Kihara Ryoichi Kishi Toshiaki Miura Shin Horiuchi Yuji Okada Kiyoshi Yase 《Liquid crystals》2013,40(11):1655-1658
Bulk samples of polymer dispersed liquid crystals (PDLCs) containing polystyrene (PS) and a thermoelastic elastomer as polymer matrices, have been prepared by a thermally-induced phase separation method. Thermomechanical analysis measurements revealed that the PDLC containing the thermoplastic elastomer possessed rubber-like elasticity even in the mesomorphic temperature range of the LC while the PDLC based on PS showed plastic deformation during the measurement. 相似文献
76.
Park Jae-Hyeok Hagio Takeshi Kamimoto Yuki Ichino Ryoichi 《Journal of Solid State Electrochemistry》2021,25(6):1901-1913
Journal of Solid State Electrochemistry - As a new trial to improve the corrosion resistance of the Fe-W alloy platings, Fe-W alloys incorporating a small amount of Zn, namely novel ternary Fe-W-Zn... 相似文献
77.
Yoshinobu Oshikiri Makoto Miura Ryoichi Aogaki 《Russian Journal of Electrochemistry》2012,48(6):643-649
The reliability of the measurement of the change in partial molar volume between product and reactant ions measured by gravity electrode (GE) was examined by the thermodynamic measurement of pycnometer (PM). Since the PM method requires an experimental equation of the apparent molar volume to calculate the partial molar volumes of the individual ions, the most suitable experimental equation must be first determined. As a test reaction for the experiment, oxidation of ferrocyanide (FERO) ion to ferricyanide (FERI) ion was adopted. After fitting several experimental equations to the data of the apparent molar volumes by the PM method, the calculated changes in the partial molar volume were compared with the data of the GM method. Then, it is concluded that the polynomial with a degree of 3 of the logarithm of the molality of the FERO ion suggests the most suitable equation. As a result, the reliability of the GE method was also experimentally validated. 相似文献
78.
An anionic amphiphile has been found to form extremely hydrophobic sites in water and specifically incorporate stilbazolium-based compact hemicyanine dyes as monomeric species, resulting in induction of intense fluorescence emission. 相似文献
79.
Highly enantioselective hydrogenation of various N-Boc-indoles proceeded successfully in the presence of the ruthenium complex generated from an appropriate ruthenium precursor and a trans-chelate chiral bisphosphine PhTRAP. Various 2- or 3-substituted indoles were converted into chiral indolines with high enantiomeric excesses (up to 95% ee). The PhTRAP-ruthenium catalyst was able to promote the hydrogenation of 2,3-dimethylindoles, giving cis-2,3-dimethylindolines with 72% ee. 相似文献
80.
Oka T Ito K Muramatsu M Ohdaira T Suzuki R Kobayashi Y 《The journal of physical chemistry. B》2006,110(41):20172-20176
Nanoporous polysiloxane films were fabricated by plasma polymerization of hexamethyldisiloxane mixed with cyclohexane under different conditions. The pores were generated through the elimination of carbonaceous aggregates (porogen) by annealing at 600 degrees C. Results of spectroscopic ellipsometry, Fourier transform infrared spectroscopy, and positron annihilation lifetime spectroscopy suggest that not only film porosity but also average pore size depends on the amount of the decomposable porogen. The pore size was controllable in a range between 0.6 and 1.0 nm in radius by proper selection of the substrate temperature and precursor composition. 相似文献