INFLUENCE OF TEMPERATURE ON THERMAL CONDUCTIVITY OF BLACK COAL

Author(s):  
A.E. Ramazanova ◽  

Экспериментально измерена теплопроводность сухого и влагонасыщенного образцов угля в области температур от 298 до 500 К. Теплопроводность угля увеличивается с температурой и проходит через максимум около 390 К, что объясняется выделением летучих веществ и термическим разложением. Значительная разница в поведении теплопроводности наблюдается до и после термической обработки угля, у которого теплопроводность постепенно увеличивается с температурой без максимума и минимума.

2013 ◽  
Vol 795 ◽  
pp. 419-423 ◽  
Author(s):  
J.H. Lim ◽  
C.K. Yeoh ◽  
Pei Leng Teh ◽  
W.M. Arif ◽  
A. Chik

In this paper, different sintering temperature used to study the influence of temperature on the structural and thermal properties of zinc oxide (ZnO). On this research, the sample was prepared by solid-state method for zinc oxide (ZnO) at different sintering temperature which was 700°C, 800°C and 900°C. It was observed that the density of bulk ZnO that sintering at 900°C had the higher value of density 5.03 g/cm3. The microhardness of the bulk ZnO had a higher measurement 397.3 Hv after sintered at 900°C. ZnO that sintering at 900°C had been observed that had thermal conductivity 1.1611W/cm-K in the sintering temperature range 700°C to 900°C.


Author(s):  
T. Geipel ◽  
W. Mader ◽  
P. Pirouz

Temperature affects both elastic and inelastic scattering of electrons in a crystal. The Debye-Waller factor, B, describes the influence of temperature on the elastic scattering of electrons, whereas the imaginary part of the (complex) atomic form factor, fc = fr + ifi, describes the influence of temperature on the inelastic scattering of electrons (i.e. absorption). In HRTEM simulations, two possible ways to include absorption are: (i) an approximate method in which absorption is described by a phenomenological constant, μ, i.e. fi; - μfr, with the real part of the atomic form factor, fr, obtained from Hartree-Fock calculations, (ii) a more accurate method in which the absorptive components, fi of the atomic form factor are explicitly calculated. In this contribution, the inclusion of both the Debye-Waller factor and absorption on HRTEM images of a (Oll)-oriented GaAs crystal are presented (using the EMS software.Fig. 1 shows the the amplitudes and phases of the dominant 111 beams as a function of the specimen thickness, t, for the cases when μ = 0 (i.e. no absorption, solid line) and μ = 0.1 (with absorption, dashed line).


2010 ◽  
Vol 25 (1) ◽  
pp. 93-105 ◽  
Author(s):  
Daniel Żarski ◽  
Dariusz Kucharczyk ◽  
Wojciech Sasinowski ◽  
Katarzyna Targońska ◽  
Andrzej Mamcarz

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