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991.
We investigate the thermodynamic properties of some quantum statistical systems with a fractional Hamiltonian in D-dimensional space. We calculate the partition function of the system of N fractional quantum oscillators and the thermodynamic quantities associated with it. We consider the thermal and critical properties of both Bose and Fermi gases in the context of the fractional energy and described by a fractional derivative. 相似文献
992.
Z. N. Ovsyannikov 《Doklady Mathematics》2016,93(1):65-68
The possible number of shortest paths joining points in the metric space of compact sets in Euclidean space endowed with the Hausdorff metric is studied. For all n ≤ 1000, except eight values, it is checked whether n can equal the number of such shortest paths. In particular, new lacunas are found, namely 41, 59, and 67 (previously, only two such lacunas, 19 and 37, were known). 相似文献
993.
Electron-positron production processes occurring in the interaction of 1018–1020 W/cm2 laser radiation with high-Z targets are examined. Computational results are presented for the pair production and the positron yield from the target
with allowance for the contribution of pair production processes due to electrons and bremsstrahlung photons. Monte Carlo
simulations using the PRIZMA code confirm the estimates obtained. The possible positron yield from high-Z targets irradiated with 102–103 TW laser radiation is estimated to be 109–1011.
Pis’ma Zh. éksp. Teor. Fiz. 67, No. 4, 239–244 (25 February 1998) 相似文献
994.
X射线荧光基本参数法测定Y1—xCexBa2cu3Oy强的钇铈钡铜 总被引:2,自引:0,他引:2
本文用X射线荧光光谱基本参数法测定了Y1-xCexBa2Cu3Ox系列样品中的钇铈钡铜含量,然后折算成它们的原子比,测量的结果与ICP的结果接近,为非破坏地测定高温超导体的实际组分进行了一次尝试。 相似文献
995.
本工作利用光栅刻线数为3600条/mm的高分辨率ICP-AES光谱仪,详细研究了镝基体对其他14个稀土元素共66条“首选分析线”的光谱干扰情况。 相似文献
996.
For the first time, barium ferrite films with in-plane orientation were prepared at 700°C by pulsed laser deposition technique (PLD) on Si(1 1 1) without any post-annealing. An amorphous Ba–Fe–O film is used as underlayer to facilitate the crystallization and improve the orientation of films. Sharp (1 1 0) and (2 2 0) peaks appeared in the XRD pattern. The surface morphologies observed by SEM are similar to the typical computer generated grain arrangements obtained by Suzuki et al. in their micromagnetics study. Furthermore, a particular kind of structure of film cross-section was identified in PLD for barium ferrite films. The grain size is about 3 μm, and the coercivity is around 1500 Oe. 相似文献
997.
Targeted damage effects of high intensity focused ultrasound (HIFU) on liver tissues of Guizhou Province miniswine 总被引:12,自引:0,他引:12
Wang ZB Wu F Wang ZL Zhang Z Zou JZ Liu C Liu YG Cheng G Du YH He ZC Gu ML Wang ZG Feng R 《Ultrasonics sonochemistry》1997,4(2):181-182
HIFU can pass through tissues and accurately damage target tissues inside organisms. This article reports on the oriented damage effects of HIFU upon miniswine internal and external liver tissues, and suggests a new conception of the 'biological focal field'. The results revealed that: (1) HIFU can be used to damage accurately liver tissues under the guide of a B-modal ultrasound device; (2) the scope of the injury is connected with sound intensity and irradiation time; and (3) the different layers of tissue through which the ultrasound has passed remain undamaged. 相似文献
998.
In this paper, we show the existence of Landau constant for functions with logharmonic Laplacian of the form F(z) = ∣z∣2L(z) + K(z), ∣z∣ < 1, where L is logharmonic and K is harmonic. Moreover, the problem of minimizing the area is solved 相似文献
999.
稀土元素原子发射光谱及其谱线干扰的高分辨率ICP—AES研究… 总被引:1,自引:1,他引:1
稀土元素在当今生产、生活中具有极重要的地位,由于稀土元素的原子发射光谱极为复杂,因此光谱干扰给稀土元素的原子发射光谱分析带来极大的困难。本工作利用高分辨率ICP-AES仪器详细研究了Sm基体对其他稀土元素分析线的光谱干扰,获得了大量的光谱及光谱干扰信息,为以稀土为基体的痕量稀土分析线的选择及光谱分析提供了依据。 相似文献
1000.
B.W. Wang Z.D. Zhang S.L. Tang X.M. Jin X.G. Zhao 《Journal of magnetism and magnetic materials》1997,170(3):198
Structure, Curie temperature and magnetostriction of RFex (1.6 ? x ? 2.0) and R(Fe1−yTiy)1.8 (y ? 0.2) alloys (RDy0.65Tb0.25Pr0.1) have been investigated using optical microscopy, X-ray diffraction, AC initial susceptibility and standard strain gauge techniques. The homogenized RFex alloys are found to be essentially single phase in the range of 1.8 ? x ? 1.85. The second phase is a rare-earth-rich phase when x ? 1.8, and (Dy, Tb, Pr)Fe3 phase when x ? 1.85. X-ray diffraction indicates that the R(Fe1−yTiy)1.8 alloys contain a small amount of Fe2Ti phase when y ? 0.05, which increases with the increment of Ti content. The Curie temperature of R(Fe1−yTiy)1.8 alloys slightly enhances with increasing Ti concentration when y ? 0.05, then remains almost unchanged in the range of 0.05 ? y ? 0.20. The magnetostriction of RFex alloys is improved when x ? 1.80 and reduced by increasing Fe content when x ? 1.85. The magnetostriction of R(Fe1−yTiy)1.8 alloys is lowered by increasing Ti content. 相似文献