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41.
42.
R.G. Abhilash Kumar K. Vinod U. Syamaprasad 《Applied Physics A: Materials Science & Processing》2007,88(2):243-247
MgB2/Fe wires were prepared by electrical self-heating of in situ powder-in-tube wires for the first time at ambient conditions.
Characterization of the wires processed at 750 °C, 800 °C and 850 °C for 15 min by XRD, SEM, ϱ–T, susceptibility and JC measurements shows that the MgB2 formed is of high quality particularly with respect to phase purity and transport JC. The method considerably reduces the overall energy consumption vis-à-vis the production cost, simplifies the complexity
of the fabrication procedure and is promising for manufacture of high-quality MgB2 superconducting wires.
PACS 74.70.Ad; 74.62.Bf; 74.25.Fy; 74.25.Ha; 81.20.Hy 相似文献
43.
44.
Sherif Yehia C. Mitros Sanjeev Kumar S. Jha Glenn M. Julian R. A. Dunlap 《Hyperfine Interactions》1987,34(1-4):415-418
The systematics of hyperfine magnetic fields at sp impurities on the Z-sites in Co based Heusler alloys are investigated. New TDPAC measurements of Cd hyperfine fields are reported. 相似文献
45.
Arup Baksi Bidyut Kumar Roy Rasajit Kumar Bera 《Mathematical and Computer Modelling》2006,44(11-12):1069-1079
The fundamental equations of the problems of generalized thermoelasticity with one relaxation parameter including heat sources in infinite rotating magneto-thermo-viscoelastic media have been derived in the form of a vector matrix differential equation in the Laplace transform domain for a one dimensional problem. These equations have been solved by the eigenvalue approach to determine deformations, stress, and temperature. The results have been compared to those available in the existing literature. The graphs have been drawn to show the effect of rotation in the medium. 相似文献
46.
47.
The mass spectrum ofcb meson is investigated with an effective quark-antiquark potential of the form -αc/r +Ar
νwith ν varying from 0.5 to 2.0. TheS andP-wave masses, pseudoscalar decay constant, weak decay partial widths in spectator model and the lifetime ofB
cmeson are computed. The properties calculated here are found to be in good agreement with other theoretical and experimental
values at potential index,ν = 1 相似文献
48.
A non-fused fiber coupler for side-pumping of double-clad fiber lasers 总被引:17,自引:0,他引:17
A non-fused fiber coupler is demonstrated for side-pumping of the double-clad fiber (DCF) lasers by adhesive techniques. The fiber coupler is fabricated by adhering an angularly polished single-clad fiber (SCF) to the inner cladding of the DCF. The pumping light is launched from the SCF by total inner reflection. Coupling coefficient as a function of coupling angle, bend distance, and backward scattering is investigated. The field distribution in DCF is also discussed. 相似文献
49.
A short and efficient RCM route is reported for the construction of the key nine-membered B ring of eleutherobin starting from the readily available 1,2,5,6-diisopropylidene-d-glucose. 相似文献
50.
Munish Kumar 《Journal of Physics and Chemistry of Solids》2004,65(6):1177-1180
A critical analysis of the Suzuki, Shanker, and Kumar formulations is presented by studying different classes of materials under high pressure. A similar trend for all the materials studied in the present work, demonstrates that Suzuki formulation is not capable to yield compression behaviour of solids. The Shanker formulation improves the results obtained by the Suzuki formulation in small compression range (0.9<V/V0<1). For further compressions Shanker formulation also fails. On the other hand, the Kumar formulation is found to work well for the entire range of pressure. The reasons for the failure of Suzuki and Shanker formulations are discussed. 相似文献