Journal of Applied Physics
A compound Nd5Co21B4 belonging to the series Rm+nCo5m+3nB2n with m=3, n=2 has been synthesized by melt spinning. The crystal structure and magnetic properties of the compound have been studied by means of x-ray diffraction and magnetic measurements. The compound crystallizes in a hexagonal structure with space group P6/mmm. The Curie temperature, the saturation moment, and the planar anisotropy field of the compound are 570 K, 31.1 mu (B)/f.u., and 861 kOe, respectively. (C) 2001 American Institute of Physics.
关键词:
n = 0;electronic-structure;anisotropy
Journal of Applied Physics
The effective magnetic anisotropy (K-eff) of nanocrystalline Fe89Zr7B4 soft magnetic alloys with different bce Fe grain sizes; (D) has been investigated by using the law of approach to saturation. The effective magnetic anisotropy of the alloys is found to be considerably depressed. The values of K-eff for the alloys (from 879 to 1038 J/m(3)) are very close to those of the nanocrystalline Fe73.5Cu1Nb3Si13.5B9 soft magnetic alloys, suggesting that the relatively lower permeability of the alloys is independent of the factor of K-eff. With an increase of grain size, K-eff is slightly increased. However, the grain size dependence of K-eff is obviously deviated from the K(eff)proportional to D-6 law, which might be mainly attributed to the residual amorphous phase in the alloys. (C) 1996 American Institute of Physics.
关键词:
grain-structure
Powder Diffraction
K(2)Zn(3)(P(2)O(7))(2) was synthesized by solid state reaction and its crystal structure was determined by ab initio method from powder X-ray diffraction (XRD) data. The title compound was determined to be orthorhombic with space group P2(1)2(1)2(1), Z=4, and lattice parameters a=12.901(8) angstrom, b=10.102(6) angstrom, and c=9.958(1) angstrom. Values of lattice parameters from 303 to 573 K were measured by temperature-dependent XRD. Thermal expansion coefficients alpha(0), lattice parameters, and cell volume at 0 K were determined to be alpha(0)(a)=1.62327X 10(-4)/K, a(0)=12.855(4) angstrom, alpha(0)(b) = 1.17921 X 10(-4)/K, b(0)=10.070(8) angstrom, alpha(0)(c)=2.62364X 10(-4)/K, c(0)=9.880(4) angstrom, and alpha(0)(V) = 6.599 X 10(-2) /K, V(0) = 1278.967(0) angstrom(3). The specific heat equation as a function of temperature was determined to be C(p)=0.77115 +0.00231 T-1241.60027T(-2)- 1.4133 X 10(-6)T(2) (J/K g), for temperatures from 198 to 710 K. The melting point estimated from the mu-DTA heating curve is 795 degrees C. (C) 2008 International Centre for Diffraction Data. [DOI: 10.1154/1.2992517]
关键词:
K(2)Zn(3)(P(2)O(7))(2);structure determination;thermal expansion;coefficient;specific heat;powder-diffraction;refinement;zno
朱佳庆
,
何俊伟
,
李云德
原子核物理评论
计算了pp和p碰撞中J/ψ的领头阶光生过程的产额。运用非相对论量子色动力学回顾了重夸克偶素产生的色单态机制与色八重态机制,并将它们分别用于处理直接光子过程和分解光子过程。通过与J/ψ产生的领头阶结果的对比可以看出,光生过程对J/ψ产额的修正在大横动量区域变得明显。
关键词:
光生过程
,
大横动量区域
,
重夸克偶素
Journal of Applied Physics
The C15 Laves phase with composition Tb0.7Pr0.3(Fe0.9B0.1)1.93 has been synthesized by mechanical alloying and subsequent annealing process. The structure and magnetic properties of Tb0.7Pr0.3(Fe0.9B0.1)(1.93) have been investigated. The effect of the annealing on the magnetic properties has been studied. The samples annealed at 773 K are found to have a coercivity of 6.66 kOe at room temperature. The coercivity decreases monotonically with increase in the annealing temperature. The epoxy/Tb0.7Pr0.3 (Fe(0.9)B0.1) 1.93 composites have been produced by a cold compression-molding technique. The magnetostriction of the epoxy/Tb0.7Pr0.3(Fe0.9B0.1)(1.93) composites with different weight ratios of epoxy resin to powder is measured by a standard strain technique. The Tb0.7Pr0.3(Fe0.9B0.j)1.93 Composites, with a weight ratio of epoxy resin to powder of 5: 100, have a high magnetostriction of 810 ppm, at an applied magnetic field of 12 kOe. The Tb0.7Pr0.3(Fe0.9B0.1)(1.93) alloy combines a high magnetostriction with a low coercivity, which is a promising magnetostrictive material. (c) 2005 American Institute of Physics.
关键词:
anisotropy compensation;compound
Materials Letters
The effects of P and B on the creep behavior of 718 alloys are discussed in this paper. The result implies that P and B have little effect on the gamma" and gamma' phases of the alloy, but they can enhance the grain boundary strength by segregating there, which can be of beneficial to the higher creep properties. P also may increase the grains strength through solid solution. The beneficial effect of P and B were presented in both standard IN718 alloy and DA718 alloy. Adding P and B together does a better work than adding P alone. (c) 2006 Elsevier B.V. All rights reserved.
关键词:
P and B;718 alloy;creep;grain boundaries;heat treatment;stress rupture;phosphorus;superalloy;boron
