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2.
M. Bennahmias H. B. Radousky T. J. Goodwin R. N. Shelton 《Journal of Electronic Materials》1993,22(10):1189-1193
Magnetic characterization has been performed on the members of the cuprateniobate RBa2Cu2NbO8 (R = Pr, Nd, and La) series and R1.5Ce0.5Sr2Cu2NbO10 (R = Pr, Eu, Nd, and Sm) series. The PrBCNO samples show a signature in the magnetization of a magnetic ordering at 12K.
The PrCSCNO sample is nonsuperconducting and shows two distinct orderings at 17K and 53K. No such magnetic phase transition
is observed down to 2K in the Nd and La based RBCNO materials or the Nd, Sm, and Eu based RCSCNO materials. Measurements of
the lower critical field curve, dc irreversibility line, and critical curent densities are reported for each of the superconducting
NdCSCNO, SmCSCNO, and EuCSCNO compounds. 相似文献
3.
本文着重介绍武汉钢铁公司近年来研制开发的第二代高强度低合金钢—高强韧性WDL系列钢的综合性能及应用情况。该钢具有优异的焊接性能和低温韧性,板厚≤50mm钢板焊前不预热或稍加预热而不产生焊接裂纹,是制造大型压力容器(特别是低温和常温球罐)、水电站压力钢管和水轮机蜗壳、高寒地区使用的大型工程机械、大跨度桥梁及海上采油平台等装备的理想用材。 相似文献
4.
5.
Ali Bayri Mustafa Sulu 《Journal of Inorganic and Organometallic Polymers and Materials》2006,16(2):185-188
This study reports the magnetic structures of newly reported trinuclear vanadium(II)–diamine complexes. Using the isotropic
Heisenberg exchange Hamiltonian, it is suggested that there are strong intramolecular antiferromagnetic interactions among
the vanadium(II) ions. It is also suggested that these complexes are good candidates to the geometrically frustrated systems.
For part 1 see A. Bayri, J. Inorg. Organomet. Polym. Mater., (in press)
An erratum to this article can be found at 相似文献
6.
This study reports the magnetic properties of newly reported nickel(II) complex of the antiprine Schiff base of 3-formylsalicylic
acid. Using the isotropic magnetic interaction model it is suggested that there is a strong antiferromagnetic interactions
between metal centers in dimeric units. It is also suggested that the system become demagnetized below a certain temperature.
An erratum to this article can be found at 相似文献
7.
LimingZhang 《材料热处理学报》2004,25(5):234-238
Microstructure and phase transformation in the Al-Cu-Fe alloys of the approximate compositional range of 20-50 at.% Cu and 2 - 10 Fe at.% have been investigated from samples quenched from their respective temperatures by means of different thermal analysis, magnetothermal analysis, scanning electron microscopy, electron probe analysis and powder X-ray diffraction. Representative phase transformations categorized as polymorphic, discontinuous precipitation,quasi-binary eutectoid, and ternary transitional U-type phase transformation are presented. These phase transformations were found to have a common feature which consumes the β phase and appears the φ phase. A schematic diagram was proposed to demonstrate the transition processes with decreasing temperature. 相似文献
8.
Oblique Y-groove cracking test of the welding cold cracking susceptibility of domestic X-70 pipeline steel 总被引:1,自引:0,他引:1
“Gas Transmitting From West to East Project“ is significant.it should ensure the welding quality and safety of pipeline.The task is very arduous to guarantee the quality of the projcet in the condition of long line.complex weather and geolgy features.in this paper,the welding cold cracking susceptibility of domestic X-70 pipeline steel adopted by the project, which is one of the most interesting questions of welding quality about petrol pipeline,was studied by means of oblique Ygroove cracking test.The crack ration of surface and section was tested under the conditions of different welding materials and preheat temperature.The thickness of plate stell was 14.7mm and 10.3mm.The results reveal that X-70 pipeline steel has good crack resistance.The research has important value for the construction of large-scale pipeline engineering and the application of domestic X-70 pipeline steel. 相似文献
9.
形变诱发马氏体对1Cr18Ni9Ti不锈钢应力腐蚀破裂的影响 总被引:2,自引:0,他引:2
通过低温(-70℃)拉伸方法,制备出具有不同马氏体(铁磁相)含量的1Cr18Ni9Ti(AISI321)奥氏体不锈钢试件。采用恒载荷法对双边缺口试样进行应力腐蚀试验,测定了不同马氏体含量的试样在氯化物介质中应力腐蚀破裂(SCC)的归一化门槛值。用SEM观察断口形貌。结果表明:当铁磁相含量小于5%时,材料的SCC敏感性随含量增加而减小;在5~15%范围内,SCC敏感性不断增加;在15~24%区域中,材料的SCC敏感性迅速下降;超过24%,SCC敏感性又有所上升。 相似文献
10.
D. K. Wickenden T. J. Kistenmacher J. Miragliotta 《Journal of Electronic Materials》1994,23(11):1209-1214
The magnitude of the χ xxxx (3) element of the third-order optical susceptibility was measured in a series of wurtzite phase GaN nucleation layers (~450Å) deposited on (00.1) sapphire at 540°C and annealed to various temperatures up to 1050°C. The nonlinear optical response exhibited a significant increase in films that were annealed to temperatures in the range of 1015 to 1050°C. In addition, the correlation between the magnitude of χ xxxx (3) with both the maximum value of the linear absorbance gradient and the residual homogeneous strain in the overlayer suggests that variations in the crystalline content of the film and the bonding distance between the Ga and N atoms are primary factors in determining the third-order nonlinearity in GaN. 相似文献