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92.
A thermodynamic modeling of the C-Cr-Ta ternary system 总被引:1,自引:0,他引:1
Chunsheng Sha Mengjie Bu Honghui Xu Yong Du Shequan WangGuanghua Wen 《Journal of Alloys and Compounds》2011,509(20):5996-6003
93.
L. ZhouC.P. Wang Y. YuX.J. Liu H. ChinenT. Omori I. OhnumaR. Kainuma K. Ishida 《Journal of Alloys and Compounds》2011,509(5):1554-1562
The isothermal sections of the Co-Nb-Ta ternary system at 900 °C, 1000 °C, 1100 °C, 1200 °C, 1300 °C have been experimentally determined by electron probe microanalysis (EPMA) and X-ray diffraction (XRD) techniques on the equilibrated alloys. On the basis of the experimental data investigated in the present work, the phase equilibria in the Co-Nb-Ta system has been thermodynamically assessed by using CALPHAD (CALculation of PHAse Diagrams) method, and a consistent set of the thermodynamic parameters leading to reasonable agreement between the calculated results and experimental data was obtained. 相似文献
94.
The specific heat of NpGa3 has been measured for the first time. The magnetic transitions and more generally the full magnetic phase diagram have been re-established precisely. The Sommerfeld coefficient and the magnetic entropy point to a rather localized system, in agreement with previous studies, in particular high pressure Mössbauer and resistivity. The comparison with other NpX3 suggests that NpGa3 is the most localized member of the series. 相似文献
95.
J.R.D. Copley 《Nuclear instruments & methods in physics research. Section A, Accelerators, spectrometers, detectors and associated equipment》2011,659(1):403-410
We have used the method of acceptance diagrams to compute the performance of low energy neutron removal mirrors, or “deflectors”, placed within a parallel neutron guide. Such devices are typically used to remove long wavelength neutrons from cold neutron beams. With appropriate coatings they may also be used as low energy neutron polarizers, ideally transmitting one spin state and reflecting the other spin state out of the beam. Within the small angle approximation, ignoring absorption, and representing reflectivities using unit step functions (either 0% or 100%, depending on the angle of incidence and the critical angle), the transmission probability reduces to a function of 3 ratios among 4 angles: the inclination angle of the deflector and the critical angles (which are proportional to neutron wavelength) of the upstream entrance guide, the deflector, and the guide within which the deflector is placed. The results of the acceptance diagram calculations, and of complementary ray-tracing calculations using realistic reflectivity profiles for the deflector, should benefit scientists and engineers involved in the design of neutron scattering instruments that potentially incorporate neutron deflectors. 相似文献
96.
Inhibition of the corrosion of mild steel in 1.0 M HCl solution by a Schiff base compound named 2-[(4-phenoxy-phenylimino)methyl]-phenol (APS) was investigated at different temperatures (25–55 °C) using electrochemical measurements. The inhibition efficiency increased as APS concentration and temperature increased. It was found that adsorption for APS on mild steel complies with the Langmuir adsorption isotherm in all studied temperature. Thermodynamic parameters (ΔGads, ΔHads and ΔSads) for APS adsorption on mild steel were found out and discussed at each temperature. Time dependency of mild steel in 1.0 M HCl solution in the absence and presence of APS was also studied. The surface morphology of mild steel was examined via SEM analysis. 相似文献
97.
The objective of this work is proposing a simple thermodynamic model to explain the increase in the solubility limit of the powders of the Cu–Mo systems or other binary systems processed by mechanical alloying. In the regular solution model, the effects of crystalline defects, such as; dislocations and grain boundary produced during milling were introduced. The model gives results that are consistent with the solubility limit extension reported in other works for the Cu–Cr, Cu–Nb and Cu–Fe systems processed by mechanical alloying. 相似文献
98.
99.
The thermodynamics of the liquid phase migration in a nanodispersed composite body has been studied. An expression describing the variation of the Gibbs potential in the course of the above process has been derived. The notion “the migration pressure” has been introduced. The equation for the migration pressure has been derived, which includes size of nanoparticles, interphase and surface tensions and the variation of the area of contact and interphase surfaces in the course of migration. 相似文献
100.
DaeWha Kang 《Architectural Design》2015,85(4):122-127
How might architectural thinking and processes shift over the next 35 years? How might the architect's role be redefined with shifting ethical values? Could the architect be viewed as less of a design professional and more of a curator engaged in the development of healthy holistic environments, catering for all of society's needs? DaeWha Kang , an architect from 2050, writes to his earlier self, critiquing the work that he undertook in independent practice and as a design director at Zaha Hadid Architects in the mid-2010s. He describes how his design methodologies have evolved in the intervening years. 相似文献