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501.
Ryugo S. HAYANO Masaharu TSUBOKURA Makoto MIYAZAKI Hideo SATOU Katsumi SATO Shin MASAKI Yu SAKUMA 《Proceedings of the Japan Academy. Series B, Physical and biological sciences》2015,91(3):92-98
Comprehensive whole-body counter surveys of Miharu-town school children have been conducted for four consecutive years, in 2011–2014. This represents the only long-term sampling-bias-free study of its type conducted after the Fukushima Dai-ichi accident. For the first time in 2014, a new device called the Babyscan, which has a low 134/137Cs MDA of <50 Bq/body, was used to screen the children shorter than 130 cm. No child in this group was found to have detectable level of radiocesium. Using the MDAs, upper limits of daily intake of radiocesium were estimated for each child. For those screened with the Babyscan, the upper intake limits were found to be ≲1 Bq/day for 137Cs. Analysis of a questionnaire filled out by the children’s parents regarding their food and water consumption shows that the majority of Miharu children regularly consume local and/or home-grown rice and vegetables. This however does not increase the body burden. 相似文献
502.
503.
Katsumi Shozugawa Naoki Hara Yutaka Kanai Motoyuki Matsuo 《Hyperfine Interactions》2012,207(1-3):89-95
Weakened hypoxia in the past 30?years at a dredged area in Tokyo Bay was proven by the existence of amorphous hematite (α-Fe2O3) in sediments. The chemical states of iron in sediments can become a proxy for the scale of anoxia at the time of sedimentation. In 2009, we collected core sediments from a dredged area off Makuhari in Tokyo Bay that is very strongly anoxic in the summer. Every layer of the sediments was analysed by 57Fe M?ssbauer spectroscopy and excess 210Pb dating, and amorphous hematite was identified in the sediments from the 1976–1979, 1986–1989 and 2006–2009 layers. Using an estimate based on the Eh-pH diagram optimized for the sedimental environment, the existence of hematite in the dredged area proves that the scale of hypoxia/anoxia is decreasing, and these results agree well with the observed dissolved oxygen level of the seawater mass. 相似文献
504.
505.
In the path integral representation, the Hamiltonian in a quantum system is associated with the Hamiltonian in a classical system through the Weyl transformation. From this, it is possible to describe the time evolution in a quantum system by the Hamiltonian in a classical system. In a Bose system, the Weyl transformation is defined by the eigenstates of the canonical operators, since the Hamiltonian is given by a function of the canonical operators. On the other hand, in a Fermi system, the Hamiltonian is usually described by a function of the creation and annihilation operators, and hence the Weyl transformation is defined by the coherent states which are the eigenstate of an annihilation operator. Here, we formulate the Weyl transformation in Fermi systems in terms of the eigenstates of the canonical operators so as to clarify the correspondence between both systems. Using this, we can derive the path integral representation in Fermi systems. 相似文献
506.
CMC (Critical Micelle Concentration) is an important parameter of surfactant. It has been reported that it changes with ionic strength, temperature, additives, etc. Therefore, it could not be overestimated to develop the determination method of CMC of surfactants. Recently,current method using CE instrument and CE method have been reported. This paper presents an new method for determining CMC of anionic surfactants by ligand exchange micellar electrokinetic chromatography. 相似文献
507.
The effects of pressure, solvent on the intramolecular spin exchange of biradicals having two nitroxide fragments linked by a long flexible chain were studied by means of highpressure EPR technique. It was found that the intramolecular exchange interaction between nitroxides of biradical took place through the direct contact between them. By analyzing the observed EPR spectra, we have estimated the ratio(Τin/Τout) value of the average lifetime of the radical fragments inside a cage(Τin) to that outside the cage(Τout). The Τin/Τout values decreased with decreasing temperature, increasing pressure. The results suggest that the nearly cyclic conformation in a cage is favorable in solution. Fur ther, the rotational correlation time of individual nitroxide was estimated from the anisotropic EPR signal,, the information on the segmental motion of the nitroxide group in biradical was obtained. 相似文献
508.
Hisayoshi Kobayashi Katsumi Nakashiro Tomoatsu Iwakuwa 《Theoretical chemistry accounts》1999,102(1-6):237-243
The mechanism of ethylene epoxidation on Ag surfaces has been investigated using the density functional method and Ag
n
clusters (n = 3 to 10) modeling the Ag(111) surface. The adsorption energy of O2 to the Ag clusters was strongly dependent on the HOMO level of the cluster, and the clusters with higher HOMO levels afforded
larger O2 adsorption energies. The energetics was investigated for both the molecular and atomic oxygen epoxidation mechanisms. For
the atomic oxygen mechanism, epoxidation was found to proceed without an activation energy, whereas a small amount of activation
energy (about 5 kcal/mol) was calculated for the molecular oxygen mechanism.
Received: 2 July 1998 / Accepted: 9 September 1998 / Published online: 8 February 1999 相似文献
509.
Masayuki Ogawa Jyunichi Koyanagi Katsuya Sakuma Akira Tanaka Katsumi Yamamoto 《Journal of heterocyclic chemistry》1999,36(3):819-822
The reaction of methyl 5-(2-isocyanatophenylthio)-2-furancarboxylate 2 with N-methylpiperazine gave 5-(2-N-piperazinocarbamoylphenylthio)-2-furancarboxylate 3a . Furthermore, 4-N-methylpiperazinyl-2-methoxycarbonylfuro[2,3-b][1,5]benzothiazepine 4a was obtained by the Bischler-Napieralski reaction of 3a with phosphorus oxychloride in the present of phosphorus pentoxide. Three furobenzothiazepines could be obtained using the same method. Based on the pharmacological studies of these compounds, it was found that 4-morpholinyl-2-methoxycarbonylfuro[2,3-b][1,5]benzothiazepine 4b had anti-inflammatory activity similar to flufenamic acid. 相似文献
510.
Gotovac S Hattori Y Noguchi D Miyamoto J Kanamaru M Utsumi S Kanoh H Kaneko K 《The journal of physical chemistry. B》2006,110(33):16219-16224
Phenanthrene was adsorbed from ethanol solution to the surface of single wall carbon nanotubes, which were previously physically and chemically characterized. Different anionic surfactants were added in the solutions to enhance the phenanthrene solubility and apparently have also improved the dispersion of two respective nanotube samples used. Adsorbed amount was determined through the concentration difference measured by UV-visible spectrophotometry. Results suggest that adsorption of phenanthrene is extremely improved in the case of nanotube purified with higher quality. These findings were confirmed by X-ray photoelectron spectroscopy. The influence of the surfactant on the adsorption kinetics of phenanthrene is suggested to be significant as well. 相似文献