Heating Temperature Dependence of Cr(III) Oxidation in the Presence of Alkali and Alkaline Earth Salts and Subsequent Cr(VI) Leaching Behavior

2013 ◽  
Vol 47 (11) ◽  
pp. 5858-5863 ◽  
Author(s):  
Bram Verbinnen ◽  
Pieter Billen ◽  
Michiel Van Coninckxloo ◽  
Carlo Vandecasteele
Keyword(s):  
Temperature Dependence ◽  
Alkaline Earth ◽  
Heating Temperature ◽  
Leaching Behavior

The temperature dependence of saturated vapor pressure over alkaline-earth metal pivaloyltrifluoroacetonate complexes

2008 ◽  
Vol 82 (11) ◽  
pp. 1797-1800 ◽  
Author(s):  
Yu. A. Efimova ◽  
G. A. Abakumov ◽  
B. I. Petrov ◽  
T. S. Pochekutova ◽  
V. K. Khamylov
Keyword(s):  
Vapor Pressure ◽  
Temperature Dependence ◽  
Alkaline Earth ◽  
Saturated Vapor Pressure ◽  
Saturated Vapor ◽  
Earth Metal ◽  
Alkaline Earth Metal

scholarly journals Effect of alkaline earth metals on the heat capacity and change of thermodynamic function of AK1M2 alloy on the basis of specific aluminum

2020 ◽  
Vol 23 (3) ◽  
pp. 222-228
Author(s):  
I. N. Ganiev ◽  
S. E. Otajonov ◽  
M. Mahmudov ◽  
M. M. Mahmadizida ◽  
V. D. Abulkhaev
Keyword(s):  
Heat Capacity ◽  
Gibbs Energy ◽  
Temperature Dependence ◽  
Alkaline Earth ◽  
Reference Sample ◽  
Alkaline Earth Metals ◽  
Model Alloy ◽  
Cooling Mode ◽  
Cooling Rates ◽  
Enthalpy And Entropy

It is known that high purity aluminum with a minimum content of impurities is widely used in electronic technology for the manufacture of conductive paths in integrated circuits. Hence the development of new compositions of alloys based on such a metal is a very urgent task. One of the promising alloys based on such a metal is alloy AK1M2 (Al + 1 % Si + 2 % Cu). This alloy was accepted by us as a model alloy and subjected to modification by alkaline earth metals.Heat capacity is the most important characteristic of substances and by its variation with temperature one can determine the type of phase transformation, the Debye temperature, the energy of formation of vacancies, the coefficient of electronic heat capacity, and other properties. In the present work, the heat capacity of the AK1M2 alloy with alkaline earth metals was determined in the “cooling” mode from the known heat capacity of a reference sample from copper. For which, by processing the curves of the cooling rate of samples from the alloy AK1M2 with alkaline earth metals and the standard, polynomials were obtained which describe their cooling rates. Further, by experimentally found values of the cooling rates of the standard and samples from alloys, knowing their masses, the polynomials of the temperature dependence of the heat capacity of the alloys and the standard were established, which are described by a four-term equation. Using the integrals of the specific heat, the models of temperature dependence of the change in enthalpy, entropy and Gibbs energy were established.The dependences obtained show that with an increase in temperature, the heat capacity, enthalpy, and entropy of alloys increase, and the values of Gibbs energy decrease. At the same time, additives of alkaline earth metals do not significantly reduce the heat capacity, enthalpy and entropy of the original alloy AK1M2 and increase the value of Gibbs energy. During the transition from alloys with calcium with barium, the heat capacity of the alloys decreases, which correlates with the heat capacity of pure alkaline earth metals within the subgroup.

Temperature dependence of the refractive index of alkaline earth fluorides

1976 ◽  
Vol 15 (10) ◽  
pp. 2352 ◽  
Author(s):  
H. G. Lipson ◽  
Y. F. Tsay ◽  
B. Bendow ◽  
P. A. Ligor
Keyword(s):  
Refractive Index ◽  
Temperature Dependence ◽  
Alkaline Earth

Sol-gel Processing and Characterization of Alkaline Earth and Rare-earth Fluoride Thin Films

1999 ◽  
Vol 14 (4) ◽  
pp. 1610-1616 ◽  
Author(s):  
Munehiro Tada ◽  
Shinobu Fujihara ◽  
Toshio Kimura
Keyword(s):  
Thin Films ◽  
Rare Earth ◽  
Alkaline Earth ◽  
Heating Temperature ◽  
Sol Gel ◽  
Chemical Species ◽  
Earth Metal ◽  
Homogeneous Solutions ◽  
Rare Earth Fluoride ◽  
Earth Fluoride

Alkaline earth and rare-earth fluoride thin films were prepared on silica glass substrates by a sol-gel process using trifluoroacetic acid (TFA) as a fluorine source. Homogeneous solutions were obtained by stirring a mixture of alkaline earth or rare-earth metal acetates, TFA and H2O, dissolved in isopropanol. The solutions were spin-coated and heated at 300–800 °C. The fluoride thin films were obtained by heat treatment around 400 °C in air. The crystallization behavior, the surface morphology, and the optical properties of the films depended on the heating temperature as well as the chemical species of the metal ions.

Surface Fractal Dimensionality and Hygroscopicity for Heated Wood

Holzforschung ◽  
2003 ◽  
Vol 57 (3) ◽  
pp. 289-294 ◽  
Author(s):  
T. Nakano ◽  
J. Miyazaki
Keyword(s):  
Temperature Dependence ◽  
Gas Adsorption ◽  
Heating Temperature ◽  
Chemical Properties ◽  
Fractal Dimensionality ◽  
Hydroxyl Groups ◽  
Fractal Surface ◽  
Nitrogen Gas ◽  
Chemical Changes ◽  
The Relationship

Summary The relationship between hygroscopicity and the microsurface of heated wood was examined using the fractal surface dimensionality. The hygroscopicity of heated wood decreased with the increase in heating temperature to 250°C, and then decreased again above 350°C after increasing up to 350°C. This change corresponded to chemical changes in the wood, especially a reduction in hydroxyl groups, up to 250°C, and to the temperature dependence of the fractal dimensionality calculated from nitrogen gas adsorption above 250°C. The fractal dimensionality increased gradually from 100 to 250°C, followed by a rapid increase above 250°C with a peak at 350°C, and leveled off above 400°C. From the results, it is concluded that hygroscopicity of heated wood changes at 250°C and that it is dependent upon the chemical properties of wood below 250°C and upon the surface complexity above 250°C.

Sign in / Sign up

Export Citation Format

Share Document