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41.
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
42.
Takafumi Seto Kenji Koga Hiroyuki Akinaga Fumiyoshi Takano Takaaki Orii Makoto Hirasawa 《Journal of nanoparticle research》2006,8(3-4):371-378
Monodispersed CoPt alloy nanoparticles were synthesized by a pulsed laser ablation (PLA) technique coupled with a low-pressure operating differential mobility analyzer (LP-DMA). The CoPt alloy nanoparticles were generated by laser ablating a solid Co–Pt target. In CoPt alloy nanoparticles synthesized from a target with a Co composition of 75 at%, the nanoparticle surfaces were covered by an oxide layer and exhibited a core-shell structure. In contrast, no shell was observed in particles generated from a target with a Co:Pt ratio of 50:50 at%. According to an EDX analysis, the compositions of the individual nanoparticles were almost the same as that of the target material. Finally, the magnetic hysteresis loops of the CoPt alloy nanoparticles exhibited ferromagnetism. 相似文献
43.
Ikeda K. Kojima N. Ono Y. Kobayashi Y. Seto M. Liu X. J. Moritomo Y. 《Hyperfine Interactions》2004,156(1-4):311-314
Hyperfine Interactions - Cs2[AuIX2][AuIIIX4] (X=Cl, Br, I) is known for a perovskite-type gold mixed-valence system. We have synthesized new gold mixed valence complexes, Cs2[AuIX2][AuIIIY4] (X,... 相似文献
44.
Hiroyuki Kawai Yoichi Hayakawa Masaya Nakagawa Kazuo Furihata Haruo Seto Noboru Ōtake 《Tetrahedron letters》1984,25(18):1937-1940
Based on 1H- and 13C-NMR and mass spectral analysis and chemical degradation, the structures of degradation products of arugomycin (arugorol, AG1, AG2 and AG3) have been determined as shown in Fig. 1. 相似文献
45.
Measurement of 24-hr whole-body retention of 99mTc-MDP with a thyroid uptake probe (author's transl)
A new method for measurement of 24-hr whole-body retention (WBR) of 99mTc-MDP, using a thyroid uptake probe was established and its clinical significance was evaluated in various bone diseases. (1) Reproducibility of 24-hr WBR in 9 patients was very good. Correlation coefficient was 0.997 and coefficient of variability was only 1.83%. (2) Radiochemical purity of 99mTc-MDP was 97.8 +/- 0.7% (n = 5), indicating no significant inter-lot variations. (3) 24-hr WBR of normal adult males (n = 5) was 30.0 +/- 4.9%, which was significantly elevated compared to the reported 99mTc-HEDP WBR of 19.2 +/- 1.7%. Whole-body retentions of chronic renal failure, metastatic bone disease and hyperthyroidism groups were significantly elevated compared to that of the normal group. However, WBR of steroid-induced osteoporotic group was significantly decreased. Based on these results, this thyroid uptake probe method was simple, reproducible and accurate to measure 24-hr WBR of 99mTc-MDP. Quantification of WBR of 99mTc-MDP was of great clinical value to diagnose metabolic bone disease and to follow-up metabolic and metastatic bone diseases. 相似文献
46.
Kazuo Furihata Haruo Seto Muneki Ohuchi Noboru Otake 《Magnetic resonance in chemistry : MRC》1983,21(10):624-627
A new method based on the combination of selective proton decoupling and INEPT is explained in detail. This technique, named selective INEPT (SEL-INEPT), is a useful and sensitive method for the 13C NMR assignment of methylene carbons with non-equivalent protons. The 13C NMR spectrum of monensin has been analysed by the application of this technique. 相似文献
47.
48.
The plasminogen system is important in the proteolytic cascade that facilitates angiogenesis, a process that is essential for tumor growth and metastasis. The serine protease plasmin has a central role in the plasminogen system. This protease acts by degrading several components of the basement membrane and by activating other proteases. Therefore, inhibition of plasmin may be an effective method for blocking angiogenesis and, as a result, inhibiting the growth of primary tumors and secondary metastases. Three pairs of plasmin inhibitors were synthesized to compare the relative potency of inhibitors that are based upon a cyclohexanone or a tetrahydro-4H-thiopyran-4-one 1,1-dioxide nucleus. Compounds 1, 3, and 5 were cyclohexanone-based inhibitors, whereas compounds 2, 4, and 6 were tetrahydro-4H-thiopyran-4-one 1,1-dioxide-based inhibitors. Compounds 5 and 6 are reasonable inhibitors with IC50 values of 25 and 5.5 microM, respectively. Comparisons of the IC50 values of the three pairs show that the electron-withdrawing sulfone functional group is a beneficial element for the design of plasmin inhibitors. The presence of the sulfone increases inhibitor potency by a factor of 3-5 when compared to inhibitors that are based upon a simple cyclohexanone core. 相似文献
49.
50.
Yoichi Hayakawa Hisashi Adachi Jin Woo Kim Kazuo Shin-ya Haruo Seto 《Tetrahedron》1998,54(52):1817-15878
A new antitumor antibiotic, adenopeptin (1), was isolated from the culture broth of Chrysosporium sp. PF1201. The planar structure, which includes a tridecapeptide and a hexahydropyrrolo[1,2-a]pyrimidinium, was elucidated by mass spectrometric and NMR experiments. Adenopeptin (1) induced apoptotic cell death in cells transformed with the adenovirus oncogenes. 相似文献