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991.
992.
Khac Hieu Ho Viet Tuyen Nguyen Nguyen Van Nghia Nguyen Ba Duc Vu Quang Tho Tran Thi Hai Doan Quoc Khoa 《Current Applied Physics》2019,19(1):55-59
The pressure effects on atomic mean-square displacement, extended X-ray absorption fine structure (EXAFS) Debye-Waller factor and melting temperature of solid krypton have been investigated in within the statistical moment method scheme in quantum statistical mechanics. By assuming the interaction between atoms can be described by Buckingham potential, we performed the numerical calculations for krypton up to pressure 120?GPa. Our calculations show that the atomic mean-square displacement and EXAFS Debye-Waller factor of krypton crystal depend strongly on pressure. They make the robust reduction of the EXAFS peak height. Our results are in good and reasonable agreements with available experimental data. This approach gives us a relatively simple method for qualitatively calculating high-pressure thermo-physical properties of materials. Moreover, it can be used to verify future high-pressure experimental and theoretical works. 相似文献
993.
AbstractWe study the value semiring Γ, equipped with the tropical operations, associated to an algebroid curve. As a set, Γ determines and is determined by the well-known value semigroup S and we prove that Γ is always finitely generated in contrast to S. In particular, for a plane curve, we present a straightforward way to obtain Γ in terms of the semiring (or the semigroup) of each branch of the curve and the mutual intersection multiplicity of its branches. In the analytic case, this allows us to relate the results of Zariski and Waldi that characterize the topological type of the curve. 相似文献
994.
It is known that the kinematics on the Lorentzian surfaces changes according to the casual characters of the vector fields. Suspicions, the character of the generator curve affects the surface growth. Therefore, we determine the model of the growth function in the three-dimensional Minkowski spacetime with a null generating curve. Moreover, the proposed method is illustrated with various examples. 相似文献
995.
Effects of the single addition of nitrogen (N) and boron (B) and the combined addition of N and B on continuous cooling transformation (CCT) diagrams and properties of the three Mo–V–Ti micro-alloyed steels were investigated by means of a combined method of dilatometry and metallography. Microstructures observed in continuous cooled specimens were composed of pearlite (P), quasi-polygonal ferrite (QPF), granular bainite (GB), acicular ferrite (AF), lath-like bainite (LB) and martensite (M) depending on the cooling rates and transformation temperatures. Single addition of 12?ppm B effectively reduced the formation of QPF and broadened the cooling rate region for LB and M. Added N makes the action of B invalid and the QPF region was prominently broadened, and even though the cooling rate is higher than 50°C?s?1, it cannot obtain full bainite. 相似文献
996.
Subodh Kumar Deepika ChaturvediAshika Jain Poonam Tandon C.M. Nautiyal 《Vibrational Spectroscopy》2011,56(2):116-122
Normal modes of vibration and their dispersion for polyoxacyclobutane modification I (POCB I) have been obtained by using Urey-Bradley force field and the Wilson's GF matrix method as modified by Higgs. Characteristic features of the dispersion curves such as crossing, repulsion and regions of high density-of-states have been explained. Heat capacity measurements have been interpreted and the limitations of the present work discussed. 相似文献
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ABSTRACTThis study aimed to explore the effects of an instructional intervention in which GeoGebra and the think-pair-share method were used to teach the relationship between the graph of a parametric curve and the derivatives of its component functions. The participants in the study were 19 prospective mathematics teachers. To assess the understanding of the participants regarding the content of the instruction, two comparable tests were administered as a pre- and post-test. In order to determine whether there was a difference between the students’ performance on the two tests, a paired samples t-test was conducted on the test scores; the results revealed a significant difference in favour of the post-test. Thus, it was concluded that the adopted teaching method, which included the use of GeoGebra, in delivering the focused content had a positive impact on the students’ understanding. 相似文献
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