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排序方式: 共有468条查询结果,搜索用时 31 毫秒
431.
Y. Kikawada H. Fuji Y. Ohno T. Oi 《Journal of Radioanalytical and Nuclear Chemistry》2008,278(2):323-326
The contents of arsenic in soils collected in the Kusatsu hot spring area, Gunma, Japan, were determined by INAA, with the
average content of 36 mg/kg, which was obviously higher than that reported for the Japanese crust. The remarkably high contents
of arsenic, 170 and 130 mg/kg, were observed in the soils collected near the discharge point of the surplus hot spring water.
The distribution of arsenic in the ground suggests that arsenic originated from hot springs has been diffusing into the ground
accompanying the penetration of the hot spring water. 相似文献
432.
M. Oi 《Physics of Atomic Nuclei》2007,70(9):1577-1581
An unexpected strong anharmonicity was observed in the wobbling spectrum in 163Lu. In an attempt to understand what causes the deviation from the original wobbling model by Bohr and Mottelson, an analysis
is presented using several different approaches, such as exact diagonalization, a semiclassical model to deal with anharmonic
wobbling motion, and a microscopic method based on the self-consistent cranking calculation.
The text was submitted by the author in English. 相似文献
433.
434.
Tomoki Yabutani Yasuhiro Utsunomiya Yukiko Kado Yuji Tani Hideyuki Kishimoto Akinori Fukuda Junko Motonaka 《Analytical sciences》2006,22(7):1021-1024
We present a new multielement masking method using magnesium hydroxide coprecipitation for the selective determination of Pb by differential pulse anodic stripping voltammetry (DPASV). The recovery of Pb in the masking method was over 95%, while interfering ions (Cd(2+), Co(2+), Cu(2+), Fe(3+), Mn(2+), and Ni(2+)) could be removed at 100% from the analytical sample. A linear regression was obtained in the Pb concentration from 10 to 1000 microg kg(-1) in the existence of 100 microg kg(-1) of the interfering ions. When this method was applied to the determination of Pb in a natural water-standard reference material (NIST 1640), the determined value for Pb in this work (25.4 +/- 4.1 microg kg(-1)) almost agreed with the certified value (27.89 +/- 0.14 microg kg(-1)). 相似文献
435.
Kenta Itahashi Satoshi Itoh Nobuhisa Fukunishi Hans Geissel Ryugo S. Hayano Satoru Hirenzaki Masahiko Iwasaki Paul Kienle Rie Kimura Karl Lindberg Chiara Nociforo Hiroaki Ohnishi Shinji Okada Naoya Ono Haruhiko Outa Masaharu Sato Ken Suzuki Takatoshi Suzuki Hideyuki Tatsuno Per–Erik Tegnér Masanori Wakasugi Helmut Weick Junko Yamagata–Sekihara Toshimitsu Yamazaki Yasushige Yano Irina Zartova 《Hyperfine Interactions》2009,193(1-3):27-31
We are preparing for a high resolution spectroscopy of the 1s and 2s pionic states of 121Sn in the 122Sn(d,3He) reaction at the incident deuteron energy of ~500 MeV. The measurement will provide accurate information on the strong interaction between the pion and the nucleus, which leads to quantitative determination of the magnitude of the quark condensate at the normal nuclear density. 相似文献
436.
A micro glucose sensor consisting of an interdigitated array gold microelectrode was developed. The interdigitated array structure, which has 10 microns band width and 10 microns band gap, was fabricated in a small region (2.5 x 5 mm2) on a quartz substrate. Glucose oxidase was chemically fixed onto the electrode surface through self-assembled monolayer of 11-mercaptoundecanoic acid; ferroceneacetic acid was used as electron mediator. Electrochemical properties of the glucose oxidase-immobilized microelectrode were investigated by cyclic voltammogram measurements. Results confirmed that the reductive ferroceneacetic acid generated at counter electrode diffuses through a narrow band gap (10 microns) and can reach the working electrode surface. 相似文献
437.
Mayako Takahashi Hiromoto Watanabe Junko Kikkawa Masaki Ota Masaru Watanabe Yoshiyuki Sato Hiroshi Inomata Nobuyuki Sato 《Analytical sciences》2006,22(11):1441-1447
The extraction of carotenoids from Japanese persimmon peels by supercritical fluid extraction (SFE), of which the solvent was CO(2), was performed. In order to enhance the yield and selectivity of the extraction, some portion of ethanol (5 - 20 mol%) was added as an entrainer. The extraction temperature ranged from 313 to 353 K and the pressure was 30 MPa. The effect of temperature on the extraction yield of carotenoids was investigated at 10 mol% of the ethanol concentration in the extraction solvent, and a suitable temperature was found to be 333 K among the temperatures studied with respect to the carotenoid yield. With increasing the entrainer amount from 0 to 10 mol% at a constant temperature (333 K), the carotenoid yield in the extraction was improved, whereas the selectivity of the extracted carotenoids was drastically depressed. We also conducted qualitative and quantitative analyses for the carotenoid components in the extract by HPLC, and analyzed the extraction behavior of each individual carotenoid (alpha-carotene, beta-carotene, beta-cryptoxanthin, lycopene, lutein, and zeaxanthin). The selectivity of each carotenoid changed with the elapsed time and its time evolution was dependent on the carotenoid component, indicating that the location profile and the content can be important factors to understand the SFE behavior of each carotenoid in persimmon peels. 相似文献
438.
We describe a novel approach for fluorometry with light-emitting-diodes (LEDs) as excitation source that capitalizes on the principle of light shielding and total internal reflection to operate without optical filters. This scheme is practicable, demonstrated to significantly reduce the amount of excitation light overlapping the fluorescence signals at the photodetector, operated best with excitation light applied orthogonal to detection, and permitted higher measurement sensitivity of fluorophore emission. 相似文献
439.
Kenichi Maruyama Yuji Mishima Keiji Minagawa Junko Motonaka 《Journal of Electroanalytical Chemistry》2001,510(1-2)
A transition metal complex as an electrochemical probe of a DNA sensor must have an applicable redox potential, high binding affinity and chemical stability. Some complexes with the dipyrido[3,2-a:2′,3′-c]phenazine (DPPZ) ligand have been reported to have high binding affinity for DNA. However, it was difficult to detect the targeted DNA electrochemically using these complexes because of the relatively high redox potential. In this work, a combination of bipyridine ligands with functional groups (---NH2, ---CH3 and ---COOH) and the DPPZ ligand were studied. The introduction of electron-donating groups was effective for controlling the redox potential of the DPPZ-type osmium complex. The [Os(DA-bpy)2DPPZ]2+ complex (DA-bpy; 4,4′-diamino-2,2′-bipyridine) had a lower half-wave potential (E1/2) of 147 mV (vs. Ag AgCl) and higher binding affinity with DNA {binding constant, K=3.1×107 M−1 in 10 mmol dm−3 Tris–HCl buffer with 50 mmol dm−3 NaCl (pH 7.76)} than those of other complexes. With the single stranded DNA (ssDNA) modified gold electrode, the hybridization signal (ΔI) of the [Os(DA-bpy)2DPPZ]2+ complex was linear in the concentration range of 1.0 pg ml−1–0.12 μg ml−1 for the targeted DNA with a regression coefficient of 0.999. The detection limit was 0.1 pg ml−1. 相似文献
440.
Machiguchi T Okamoto J Morita Y Hasegawa T Yamabe S Minato T 《Journal of the American Chemical Society》2006,128(1):44-45
The first example of direct spectroscopic detection of transient species, 1,4-zwitterions, generated in a ketene-alkene reaction is reported. Also, a striking result of the intervention of an unprecedented "1,4-zwitterion neutral dimer" is presented in a new mechanistic pathway; the ketene-alkene reaction gives the product cyclobutanone from the initial cycloadduct alpha-methyleneoxetane. 相似文献