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Yoon Yeol Yoon Kil Yong Lee Kyung Seok Ko 《Journal of Radioanalytical and Nuclear Chemistry》2010,284(3):591-595
The contents of H-3 and C-14 in groundwater and surface waters around low and medium-level atomic waste repository site in
Korea were determined. The concentrations of C-14 were in the range 0.186–0.287 Bq/L. The H-3 concentration of the groundwaters
and surface waters were <0.06–5.75 and 1.22–4.74 Bq/L. The average H-3 contents of west, north and south direction were 1.18 ± 0.12,
1.11 ± 0.78 and 2.85 ± 2.66. H-3 and C-14 concentrations in the south direction were relatively higher than west and north
direction samples. The surface waters sampled from catchment were four times higher than average H-3 concentration in precipitation.
The concentrations of H-3 and C-14 within 5 km area samples were much higher than other samples. 相似文献
205.
Jeong Woon Choi Dowon HongKu-Young Chang Dong Pyo ChiSoojoon Lee 《Physics letters. A》2011,375(3):430-433
The Gisin-Hughston-Jozsa-Wootters theorem plays an important role in analyzing various theories about quantum information, quantum communication, and quantum cryptography. It means that any purifications on the extended system which yield indistinguishable state ensembles on their subsystem should have a specific local unitary relation. In this Letter, we show that the local relation is also established even when the indistinguishability of state ensembles is extended to that of operator ensembles. 相似文献
206.
Chul‐Soon Lee Zhengfei Dai Seong‐Yong Jeong Chang‐Hoon Kwak Bo‐Young Kim Do Hong Kim Prof. Ho Won Jang Joon‐Shik Park Prof. Jong‐Heun Lee 《Chemistry (Weinheim an der Bergstrasse, Germany)》2016,22(21):7102-7107
Monolayers of periodic porous Co3O4 inverse opal (IO) thin films for gas‐sensor applications were prepared by transferring cobalt‐solution‐dipped polystyrene (PS) monolayers onto sensor substrates and subsequent removal of the PS template by heat treatment. Monolayer Co3O4 IO thin films having periodic pores (d≈500 nm) showed a high response of 112.9 to 5 ppm C2H5OH at 200 °C with low cross‐responses to other interfering gases. Moreover, the selective detection of xylene and methyl benzenes (xylene+toluene) could be achieved simply by tuning the sensor temperature to 250 and 275 °C, respectively, so that multiple gases can be detected with a single chemiresistor. Unprecedentedly high ethanol response and temperature‐modulated control of selectivity with respect to ethanol, xylene, and methyl benzenes were attributed to the highly chemiresistive IO nanoarchitecture and to the tuned catalytic promotion of different gas‐sensing reactions, respectively. These well‐ordered porous nanostructures could have potential in the field of high‐performance gas sensors based on p‐type oxide semiconductors. 相似文献
207.
Quantum Spheres and Projective Spaces as Graph Algebras 总被引:5,自引:0,他引:5
The C
*
-algebras of continuous functions on quantum spheres, quantum real projective spaces, and quantum complex projective spaces
are realized as Cuntz-Krieger algebras corresponding to suitable directed graphs. Structural results about these quantum spaces,
especially about their ideals and K-theory, are then derived from the general theory of graph algebras. It is shown that the quantum even and odd dimensional
spheres are produced by repeated application of a quantum double suspension to two points and the circle, respectively.
Received: 31 January 2001 / Accepted: 29 July 2002 Published online: 7 November 2002
RID="*"
ID="*" Supported by grant No. R04–2001–000–00117–0 from the Korea Science & Engineering Foundation.
RID="**"
ID="**" Partially supported by the Research Management Committee of the University of Newcastle. 相似文献
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[reaction: see text] 2'-Deoxy-2'-C-difluoromethylene-4'-thiocytidine (4) as a potential antitumor agent was synthesized starting from L-xylose via 2-deoxy-2-C-difluoromethylene-4-thiosugar as a key intermediate. An elimination product, 8, was always formed as the major product during removal of the protecting groups under acidic or basic conditions. However, utilizing neutral reaction conditions to remove the protecting groups afforded the desired product 4 exclusively. 相似文献
210.
Ethylene is not only a substrate, but also a solvent: Catalytic intermolecular Pauson - Khand reactions of terminal alkynes were carried out in supercritical ethylene to provide 2-substituted cyclopentenones in moderate to high yields [Eq. (1)]. Under these conditions, even a low pressure of CO (5 atm) is sufficient for the reaction to take place. 相似文献