Behavior of Radionuclides During the Smelting of Noncombustible Solid Wastes

1981 ◽  
Vol 6 ◽  
Author(s):  
Makoto Osaki ◽  
Shinji Yokoi ◽  
Minoru Miyagawa

ABSTRACTThe melting process of noncombustible solid wastes seems to be one of the most promising processes for volume reduction and immobilization. This melting process needs a high temperature of around 1500° C, but the behavior of radionuclides in such a process and at such a temperature has not been fully examined. We melted small contaminated samples to examine the behavior of radionuclides. Melted products were subjected to leaching tests.Many assorted samples were melted, and we found that the vapour pressure of the radionuclide determined the distribution between melted products and dusts. The standard free energy of oxide formation and the quantity of stable nuclide of the radionuclide determined the distribution between metal and slag products. The leaching rate of melted products was sufficiently low.

Author(s):  
Shinji Kobayashi ◽  
Eiichi Ide ◽  
Shinji Angata ◽  
Akio Hirose ◽  
Kojiro F. Kobayashi

A novel bonding process using Ag metallo-organic nanoparticles has been proposed. This process is applicable to the alternative to the current high temperature solders, such as Pb-10Sn or Pb-20Sn. In this paper, Al, Ti, Ni, Cu, Ag and Au disc joints were made using the Ag metallo-organic nanoparticles in order to investigate the bondability of the various metals. These joints were evaluated based on the measurement of the shear strength, and the observation of the fracture surfaces and the cross-sectional microstructures. The shear strength of various metal joints increased in the following order: Al, Ti, Ni, Cu, Ag and Au joints. This corresponds to the order of the standard free energy value of the oxide formation for each metal. This result suggests that the carbon atoms generated by the decomposition of the organic shell of the Ag metallo-organic nanoparticles may play a role in deoxidizing the oxide film on the metal surface.


2021 ◽  
Vol 2021 (1) ◽  
Author(s):  
Joonho Kim ◽  
Seok Kim ◽  
Jaewon Song

Abstract We study the asymptotic behavior of the (modified) superconformal index for 4d $$ \mathcal{N} $$ N = 1 gauge theory. By considering complexified chemical potential, we find that the ‘high-temperature limit’ of the index can be written in terms of the conformal anomalies 3c − 2a. We also find macroscopic entropy from our asymptotic free energy when the Hofman-Maldacena bound 1/2 < a/c < 3/2 for the interacting SCFT is satisfied. We study $$ \mathcal{N} $$ N = 1 theories that are dual to AdS5 × Yp,p and find that the Cardy limit of our index accounts for the Bekenstein-Hawking entropy of large black holes.


2021 ◽  
Vol 13 (2) ◽  
pp. 535
Author(s):  
Jing Gao ◽  
Tao Wang ◽  
Jie Zhao ◽  
Xiaoying Hu ◽  
Changqing Dong

Melting solidification experiments of municipal solid waste incineration (MSWI) fly ash were carried out in a high-temperature tube furnace device. An ash fusion temperature (AFT) test, atomic absorption spectroscopy (AAS), scanning electron microscope (SEM), and X-ray diffraction (XRD) were applied in order to gain insight into the ash fusibility, the transformation during the melting process, and the leaching behavior of heavy metals in slag. The results showed that oxide minerals transformed into gehlenite as temperature increased. When the temperature increased to 1300 °C, 89 °C higher than the flow temperature (FT), all of the crystals transformed into molten slag. When the heating temperatures were higher than the FT, the volatilization of the Pb, Cd, Zn, and Cu decreased, which may have been influenced by the formation of liquid slag. In addition, the formation of liquid slag at a high temperature also improved the stability of heavy metals in heated slag.


Holzforschung ◽  
2002 ◽  
Vol 56 (1) ◽  
pp. 91-97
Author(s):  
Kei Morisato ◽  
Yutaka Ishimaru ◽  
Hiroyuki Urakami

Summary To understand the swelling phenomenon of wood in liquids,the saturated amount of adsorption of liquids onto wood and the standard free energy changes of the adsorption were determined. The saturated amount of adsorption obtained by regression for several liquids decreased with increasing molecular size of the solvents. The mechanism of wood swelling is discussed systematically taking all the liquids examined in previous experiments into account. Since methanol molecules require more energy for release from cohesive interactions within bulk liquids in the adsorption onto pre-swollen wood,the values of free energy change of adsorption for methanol were lower than the values for acetone,although the relative swelling with methanol was higher. These results suggest that although the cohesive interaction within the bulk liquids reduces adsorptivity,the phenomenon of wood swelling is influenced not only by monolayer adsorption but also by multilayer adsorption. Therefore,the cohesive interaction within the bulk liquids reduces adsorptivity but enhances the condensation which strongly influences the swelling of wood.


ChemPhysChem ◽  
2014 ◽  
Vol 16 (1) ◽  
pp. 138-146 ◽  
Author(s):  
Caroline Schuabb ◽  
Melanie Berghaus ◽  
Christopher Rosin ◽  
Roland Winter

1975 ◽  
Vol 53 (16) ◽  
pp. 2365-2370 ◽  
Author(s):  
Don Betowski ◽  
Gervase Mackay ◽  
John Payzant ◽  
Diethard Bohme

The rate constants and equilibrium constant for the proton transfer reaction [Formula: see text] have been measured at 296 ± 2 K using the flowing afterglow technique: kforward = (2.9 ± 0.6) × 10−9 cm3molecule−1s−1, kreverse = (1.8 ± 0.4) × 10−10 cm3 molecule1 s−1, and K = 16 ± 2. The measured value of K corresponds to a standard free energy change, ΔG296°, of −1.6 ± 0.1 kcal mol−1 which provides values for the standard enthalpy change, ΔH298°= −1.0 ± 0.2 kcal mol−1, the bond dissociation energy, D00(H—CN) = 124 ± 2 kcal mol−1, and the proton affinity, p.a.(CN−) = 350 ± 1 kcal mol−1.


Carbon ◽  
2002 ◽  
Vol 40 (11) ◽  
pp. 2031-2034 ◽  
Author(s):  
M Joseph ◽  
N Sivakumar ◽  
P Manoravi

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