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41.
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   
42.
43.
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   
44.
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   
45.
研究了无应力作用条件下,均匀、各向同性、圆柱形微极结构弹性板中波的传播.导出了对称和斜对称模式下波传播的特征方程.对短波这一极端情况,无应力圆板中对称和斜对称模态波的特征方程退化为Pmyle曲表面波频率方程.并得到薄板的计算结果.给出了位移和微转动分量,并绘制了相应图形.给出了若干特殊情况的研究结果及对称和斜对称模态特征方程的图示.  相似文献   
46.
This is summary of the activities of the working group on collider physics in the IXth Workshop on High Energy Physics Phenomenology (WHEPP-9) held at the Institute of Physics, Bhubaneswar, India in January 2006. Some of the work subsequently done on these problems by the subgroups formed during the workshop is included in this report.  相似文献   
47.
We consider a multipath maximum flow problem introduced by Kishimoto (Networks 27(4)(1996)279-291). The focus is on efficient transformation from arc flows into multipath flows, where a multipath flow is a nonnegative combination of multipaths. A new algorithm that is more efficient than existing ones is proposed for the transformation.  相似文献   
48.
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   
49.
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   
50.
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   
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