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141.
142.
We have investigated the structural and elastic properties
of MgB2 under high pressures using the full-potential linearized
muffin-tin orbital (FP-LMTO) scheme within the generalized gradient
approximation correction (GGA) in the frame of density functional
theory. The calculated pressure dependence of the normalized
volume is in excellent agreement with the experimental results.
At the same time the elastic constants and acoustic anisotropy
as a function of applied pressure are presented. Through the
quasi-harmonic Debye model, we also investigate the thermodynamic
properties of MgB2. 相似文献
143.
The thermodynamic properties of LiBC are investigated by using the full-potential linearized muffin-tin orbital method (FP-LMTO) within the frame of density functional theory (DFT) and using the quasi-harmonic Debye model. The dependencies of the normalized lattice parameters a/a0 and c/c0, the ratio (c/a)/2, the normalized primitive volume V/V0 on pressure and temperature are successfully obtained. It is found that the interlayer covalent interactions (Li-B bonds or Li-C bonds) are more sensitive to temperature and pressure than intralayer ones (B-C bonds), as gives rise to the extreme lattice anisotropy in the bulk hcp LiBC. 相似文献
144.
高密度氢气的分子间相互作用与状态方程 总被引:1,自引:2,他引:1
本文从高密度氢气的分子间相互作用出发进行分析,在修改范德瓦耳方程的基础上,提出了一种新的适用于高密度氢气的状态方程,并用来系统地计算了氢气在临界区的等温压缩线.在缺乏实验数据的情况下,这些理论计算结果很有用. 相似文献
145.
146.
147.
高温高压气体的状态方程与热力学性质 总被引:1,自引:2,他引:1
本文根据高温高压下气体分子要压缩的观点出发,提出了一个简单实用的高温高压气体状态方程,并用以研究和计算气体在高温高压下的热力学函数与性质. 相似文献
148.
According to the theory given in the paper[1], the long time electrolysis experiment with titanium cathode in heavy water (D2O) were done for many times by using the open-loop multi-parameters electrolysis calorimetry system, which is established by us. The specialty is that the cathode is titanium rod and the anode is platinum wire. The early experiment result[3] is still repeated in our recent experiment. The obvious "excess heat" phenomenon can take place only when the electrolysis last more than ten days and amount of "excess heat" increased with the electrolysis time. The "excess heat" can also be obtained from the "boiling to dry" experiment. In the recent experiment, we obtain the results that the amount of "excess heat" is about 3.6 times the input energy, the "excess heat" power is 76.5 W, and the "excess heat" power density is 121.7 W/cm3. After the electrolysis, the crystal structure of the Ti cathode was measured with x-ray diffraction apparatus. We found that the crystal structure of Ti cathode was changed to face-centered cubic structure of TiD2 from its hexagonal structure. This result is in agreement with the Gou's theory mentioned in reference[1]. 相似文献
149.
150.