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151.
Lyun-Su Kim Ki-dong Son Debasish Sarker Ji Hwan Jeong Sung Hong Lee 《Heat and Mass Transfer》2011,47(2):163-180
Small vapor compression refrigeration systems incorporate a non-adiabatic capillary tube called a capillary tube-suction line
heat exchanger (SLHX) in order to improve performance. The thermodynamic properties of the refrigerant in the capillary tube
and suction pipe are influenced by associated phenomena. This study compares various relevant models. Based on the comparison
recommended correlations were selected and the simulation results show that the friction factor model has the most dominant. 相似文献
152.
Effects of B and P content on structural and magnetic properties of cast iron based amorphous alloys
S. N. Kane H. J. Lee S. B. Kim Y. H. Jeong S. W. Hyun C. S. Kim L. K. Varga 《Hyperfine Interactions》2009,191(1-3):109-113
Mössbauer spectroscopy, DSC and magnetic measurements have been used to study the influence of B and P on structural; magnetic properties and thermal stability of cast iron based alloys. Results reveal that addition of B and P affects appreciably: (1) the crystallization temperature and supercooled liquid region ranging between 690–781 and 53–81 K respectively; (2) the spin texture, disorder and (3) the obtained magnetization parameters. Coercive field values range between 10.09 and 16.37 A/m, with lowest value of 10.09 A/m obtained for Ci87.82B12.17. Saturation induction (B s) values vary between 1.32 and 1.85 T. Highest B s value of 1.85 T is obtained for the Ci95.65B4.32 alloy which is at the edge of glass forming ability, with only 4.32 at.% of boron was added to the cast iron composition. Losses (at 50 Hz and 0.32 kA/m) for the studied samples range between 0.43 and 0.82 W/kg. Lowest losses of 0.43 W/kg was obtained for the Ci91.3P4.35B4.35 alloy. Phosphorous and boron additions, helps in the bulk glass forming ability, suggesting perspective applications of these cheap cast iron based soft magnetic alloys as a substitute of the conventional materials. 相似文献
153.
154.
155.
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
156.
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
157.
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
158.
159.
[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
160.
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