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231.
半群代数中理想FA良序基的构造 总被引:6,自引:0,他引:6
讨论了在半群代数k[A]中,如何利用Gause-Jordan消元法去构造半群代数的理想的良序基,进而得到理想的良性基-Groedner-基。 相似文献
232.
Mei Yang Zheng Wen-Chen Yang Yu-Guang Liu Hong-Gang 《Physica B: Condensed Matter》2012,407(21):4365-4368
The g factors g∥ and g⊥ for the tetragonally-compressed (CrO4)3− clusters in YMO4 (M=V, P) crystals are calculated from the high-order perturbation formulas based on the two-mechanism model for the compressed d1 tetrahedra with the ground state |dz2〉. From the calculated values and by considering a small admixture of the first excited state |dx2−y2〉 to the ground state |dz2〉 due to the vibrational motion of ligands (which leads a twinkling compressed tetrahedron to become an elongated one), the observed g∥ and g⊥ for Cr5+ centers in YMO4 crystals are explained reasonably. The difficulty of the large deviations of g∥ from ge (≈2.0023) in the two systems is therefore removed and the above dynamic effect may be the cause which results in the large deviation of g∥ from ge for some (CrO4)3− clusters in crystals. 相似文献
233.
XRF法测定铁矿石中TFe、SiO2和P 总被引:2,自引:0,他引:2
四硼酸锂为熔剂 ,钴为内标 ,高温熔融法对铁矿石进行均一处理 ,X射线荧光光谱法测定铁矿石中TFe、Si O2 和 P,取得满意结果。 相似文献
234.
The De Donder–Weyl (DW) Hamilton–Jacobi equation is investigated in this paper, and the connection between the DW Hamilton–Jacobi
equation and multi-symplectic Hamiltonian system is established. Based on the DW Hamilton–Jacobi theory, generating functions
for multi-symplectic Runge–Kutta (RK) methods and partitioned Runge–Kutta (PRK) methods are presented.
The work is supported by the Foundation of ICMSEC, LSEC, AMSS and CAS, the NNSFC (No.10501050, 19971089 and 10371128) and
the Special Funds for Major State Basic Research Projects of China (2005CB321701). 相似文献
235.
Bohuslav Rittich Alena Španová Petr Šálek Štěpánka Trachtová 《Journal of magnetism and magnetic materials》2009,321(10):1667-1670
Carboxyl group-containing magnetic nonporous poly(2-hydroxyethyl methacrylate-co-glycidyl methacrylate) (P(HEMA-co-GMA)) and magnetic glass microspheres were used for the isolation of bacterial DNA. P(HEMA-co-GMA) microspheres were prepared by the dispersion polymerization in toluene/2-methylpropan-1-ol mixture in the presence of magnetite nanoparticles obtained by coprecipitation of Fe(II) and Fe(III) salts with ammonium hydroxide. Carboxyl groups were then introduced by oxidation of the microspheres with potassium permanganate. The most extensive DNA recovery was achieved at PEG 6000 concentrations of 12% or 16% and 2 M NaCl. The method proposed was used for bacterial DNA isolation from different dairy products containing Bifidobacterium and Lactobacillus cells. The presence of target DNA and the quality of isolated DNA were checked by polymerase chain reaction (PCR) amplification with specific primers. 相似文献
236.
G.K.Mallot 《中国物理C(英文版)》2010,34(9)
The Compass experiment at CERN is studying the nucleon spin structure with a 160 GeV polarized muon beam and polarized targets as well as hadron structure with 190 GeV pion, kaon and proton beams. The paper gives an overview of the results for the helicity and transverse spin structure of the nucleon. A first result from the spectroscopy experiments, the observation of a resonance with exotic JPC = 1- + quantum numbers at 1660 MeV is also presented. The paper ends with an outlook to future measurements. 相似文献
237.
Effects of multiple interruptions with trimethylindium-treatment in the InGaN/GaN quantum well on green light emitting diodes 下载免费PDF全文
In this study, the influence of multiple interruptions with trimethylindium(TMIn)-treatment in InGaN/GaN multiple quantum wells(MQWs) on green light-emitting diode(LED) is investigated. A comparison of conventional LEDs with the one fabricated with our method shows that the latter has better optical properties. Photoluminescence(PL) full-width at half maximum(FWHM) is reduced, light output power is much higher and the blue shift of electroluminescence(EL) dominant wavelength becomes smaller with current increasing. These improvements should be attributed to the reduced interface roughness of MQW and more uniformity of indium distribution in MQWs by the interruptions with TMIn-treatment. 相似文献
238.
A systematic investigation concerned with phase stability, elastic properties, hardness and relevant electronic structure of Ni–P compounds (Ni3P, Ni12P5, Ni2P, Ni5P4, NiP, NiP2 and NiP3) was carried out using first principles calculations. The calculated results show that the Ni–P compounds have strong hardness, ranging from 7.80–14.54 GPa. Also, the hardness values gradually increase with the P content. Electronic structure analysis shows that the strong Ni–P and part of P–P hybrid orbitals play important roles in the hardness of these compounds. The calculated elastic constants indicated that the Ni3P, Ni12P5 and NiP2 phases are significantly anisotropic, the NiP and Ni2P exhibit some anisotropy, while the Ni5P4 and NiP3 show a relatively isotropic character. At last, the properties of these Ni–P compounds including lattice constants, thermodynamic stability, elastic constants Cij, bulk modulus B, shear modulus G, Young's modulus E and Poisson's ratio ν have been calculated. 相似文献
239.
240.