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81.
Plural samples were simultaneously analyzed in a capillary electrophoresis (CE)-chemiluminescence (CL) detector system, taking advantage of a micro-space area for reaction/detection at the tip of the capillary. The CL reaction of 1,10-phenanthroline and hydrogen peroxide was adopted and a Cu(II) sample was used as a model. Three different length capillaries were inserted into a flow-type CL detection cell made of a Teflon tube. Three samples migrated in the corresponding capillaries at the same time and mixed with the CL reagent at the tip of capillary to produce CL. The simultaneous analysis of plural samples in the present system supported the possibility that a real sample could be determined more easily, rapidly, and precisely with the calibration curve.  相似文献   
82.
A total synthesis of d1-coriolin has been accomplished starting from 1,3-cyclooctadiene, in which a rational and efficient introduction of various functional groups to the synthetic intermediate, 7-endo-t-butyldimethylsilyloxybicyclo[3.3.0]-oct-8-en-2-one, is involved.  相似文献   
83.
A polymer-based adsorption medium having molecular recognition ability for homologues of chlorinated bisphenol A produced in environment was prepared using a fragment imprinting technique. 2,6-Dimethyl phenol was utilized as a pseudo-template molecule and the adsorption media prepared was evaluated by high performance liquid chromatography (HPLC) and solid-phase extraction (SPE). As results, the adsorption medium showed preferable chromatographic retention and specific adsorption ability for the chlorinated bisphenol As having chlorine substituents at 3,5-positions through fragment imprinting effect.  相似文献   
84.
A new pentacyclic cucurbitane glucoside, named aoibaclyin (1) and a new triterpene (2) have been isolated from the EtOH extract of the fruits of Gymnopetalum integrifolium Kurz (Cucurbitaceae), together with three known compounds, bryoamaride (3), 25-O-acetylbryoamaride (4) and beta-sitosterol 3-O-beta-D-glucopyranoside (5). The structures of these compounds were elucidated by spectroscopic analyses.  相似文献   
85.
A method of analyzing plastic behavior by use of an anisotropic hardening plastic potential is proposed. The plastic potential surface in deviatoric stress space is assumed to be the same as the equi-plastic-strain surface. Stress-strain relations in combined loading and in multi-axial cyclic loading are calculated by use of the anisotropic hardening plastic potential and the normality rule of the plastic strain increment vector to the plastic potential surface, which are experimentally determined or confirmed by subjecting thinwalled tubular test specimens of 6040 brass to combined axial load, internal pressure and torsion. The calculated results agree fairly well with the experimental observations.  相似文献   
86.
T. Ueda  Y. Ikegami  K. Tada 《Few-Body Systems》1995,18(2-4):133-146
pp and πd scattering and pp →πd reaction processes at incident proton laboratory energies T L ≤ 1 GeV are studied in the framework of πNN dynamics. For this purpose three-body calculations are performed with the πN interaction in the P 11, P 33, S 11 and S 31 states and NN forces in the 3 S 1 -3 D 1, 1 S 0, and 3 P 2 states. In addition, the backward-going pion contribution at the πNΔ vertex, the πN-ρN coupling, the heavy-meson exchanges in the NN → NN driving term, and the effect of the off-shell structure in the πN-ρN P 33 interaction are taken into account. Received March 28, 1994; revised July 29, 1994; accepted for publication August 31, 1994  相似文献   
87.
A novel compound, N,N'-bis(2,4-di-sulfobenzyl)tolidine tetrasodium salt (SBT), was synthesized for use as a chromogenic indicator for oxidizing substances, and its applicability to the colorimetric determination of chlorine in water was examined.  相似文献   
88.
Line broadening and orbit dependence of the Coulomb displacement energy have been observed for the 1g9/2, 2p1/2 and 2p3/2 hole-state analogs in a series of odd-A Sn isotopes. The observed widths are discussed in terms of spreading width with main contributions from mixing with the isovector monopole state as well as the escape width.  相似文献   
89.
Various olefins were synthesized by coupling reactions via the corresponding α-stannylalkyl halides derived from aldehydes. A cross-coupling reaction using the different types of α-stannylalkyl halides, based on the difference of their reactivities, was also achieved.  相似文献   
90.
A preliminary interlaboratory study was conducted to evaluate the validity of the modified AOAC method for determination of total dietary fiber by Tada and Innami, in which the 3-step enzymatic digestion process in AOAC Method 991.43 is modified to a 2-step process without pH adjustment. Total dietary fiber contents in 8 representative foodstuffs were measured using both the original AOAC Method 991.43 and the modified method in 6 research facilities in Japan. Repeatability relative standard deviations, reproducibility relative standard deviations, and Horwitz ratio values from the modified method were equivalent to those from AOAC Method 991.43, except in the rice sample. However, this exceptional case shown in the modified method was entirely dissolved by the addition of alpha-amylase stabilizing agents. The modified method, which shortens the process of enzymatic digestion from 3 to 2 steps and in which only reaction temperature is adjusted under the same pH, was found not only to give accurate values comparable to the original method, but also to substantially reduce the labor required by the laboratory staff in the process of routine analysis. This study revealed that the validity of the modified method was further ensured by adding alpha-amylase stabilizing agents to the reaction system.  相似文献   
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