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71.
Kidera M Seto Y Takahashi K Enomoto S Kishi S Makita M Nagamatsu T Tanaka T Toda M 《Spectrochimica acta. Part A, Molecular and biomolecular spectroscopy》2011,78(3):1215-1219
We developed a detection technology for vapor forms of chemical warfare agents (CWAs) with an element analysis system using an electron cyclotron resonance ion source. After the vapor sample was introduced directly into the ion source, the molecular material was decomposed into elements using electron cyclotron resonance plasma and ionized. The following CWAs and stimulants were examined: diisopropyl fluorophosphonate (DFP), 2-chloroethylethylsulfide (2CEES), cyanogen chloride (CNCl), and hydrogen cyanide (HCN). The type of chemical warfare agents, specifically, whether it was a nerve agent, blister agent, blood agent, or choking agent, could be determined by measuring the quantities of the monatomic ions or CN(+) using mass spectrometry. It was possible to detect gaseous CWAs that could not be detected by a conventional mass spectrometer. The distribution of electron temperature in the plasma could be closely controlled by adjusting the input power of the microwaves used to generate the electron cyclotron resonance plasma, and the target compounds could be detected as molecular ions or fragment ions, enabling identification of the target agents. 相似文献
72.
Yoshihito Naka Norio Nemoto Yihu Song 《Journal of Polymer Science.Polymer Physics》2005,43(12):1520-1531
Simultaneous kinetic measurement of microscopic infrared dichroism, macroscopic stress, and mesoscale strain was used to study the deformation mechanisms of metallocene polypropylene (MPP), ethylene–butylene rubber (EBR), and their blend (MPP/EBR = 80/20 w/w). As with pure MPP, the molecular orientation in the blend is dominated by the necking of the isotactic polypropylene matrix. During the necking passage through the mesoscale sampling area, the molecular orientation of the polypropylene matrix in the blend is smaller than that in the pure polypropylene film at the same level of mesoscale strain. However, the orientation of the EBR dispersed phase in the blend is larger than that in the pure EBR film. This may result from the partial miscibility of the two ingredients in the amorphous phases and their resultant strong interfacial interaction. The large stress supported by the MPP matrix extends to the island of the EBR domain and leads to its large deformation. © 2005 Wiley Periodicals, Inc. J Polym Sci Part B: Polym Phys 43: 1520–1531, 2005 相似文献
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Determination of reduced and total ubiquinones in biological materials by liquid chromatography with electrochemical detection 总被引:2,自引:0,他引:2
A convenient and reliable liquid chromatographic (LC) method with electrochemical detection (ED) was developed for the determination of reduced (ubiquinol) and total ubiquinones in biological materials. After extraction of samples with n-hexane, ubiquinol was separated on a reversed-phase column and assayed directly by ED. In order to determine the total amount of a ubiquinone in biological samples, the unbiquinone was converted into the corresponding reduced form by treatment with sodium borohydride. No significant interfering peak (plastoquinol-9, ubichromenol-9, etc.) was observed in the elution areas of ubiquinol-7 to -11. This LC-ED method was about 70 times more sensitive than the previous LC-UV method and was able to detect 150 pg of ubiquinol-10. The method was applied satisfactorily to the determination of the contents of ubiquinol homologues in biological materials. The content of ubiquinols is a major component of the total ubiquinones in human plasma and urine and rat plasma and liver, but a minor component in rat heart and kidney. 相似文献
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Two general methods, Method A and Method B in Scheme 19, to synthesize epidithiapiperazinediones, are described. A total synthesis of racemic and optically active gliotoxin (1) and of racemic dehydrogliotoxin (53) was achieved by using Method A, whereas a total synthesis of racemic hyalodendrin (52) was completed by using Method B. 相似文献
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In the oxidation of alkyl sulfides bearing acidic α-hydrogens eiher with phenobarbital induced rabbit liver microsomal cytochrome P-450, or with the Udenfriend's model system (ferous perchlorate/ascorbic acid/oxygen system), both S-dealkylation and S-monoxygenation took place concurrently. Meanwhile, in the oxidation of simple alkyl sulfides, steeoselective S-monooxygenation was found of occur predominantly. 相似文献