scholarly journals Radionuclide Leaching from Residual Solids Remaining after Acid Dissolution of K East Area Sludge Composite

10.2172/5105 ◽  
1999 ◽  
Author(s):  
C.H. Delegard ◽  
D.E. Rinehart ◽  
C.D. Carlson ◽  
C.Z. Soderquist ◽  
S.K. Fadeff
Keyword(s):  
Acid Dissolution ◽  
Radionuclide Leaching

scholarly journals Radionuclide Leaching from Residual Solids Remaining after Acid Dissolution of Composite K East Canister Sludge

10.2172/5107 ◽  
1999 ◽  
Author(s):  
C.H. Delegard ◽  
D.E. Rinehart ◽  
C.Z. Soderquist ◽  
S.K. Fadeff
Keyword(s):  
Acid Dissolution ◽  
Radionuclide Leaching

Acceptorless amine dehydrogenation and transamination using Pd-doped layered double hydroxides

2018 ◽  
Author(s):  
Diana Ainembabazi ◽  
Nan An ◽  
Jinesh Manayil ◽  
Kare Wilson ◽  
Adam Lee ◽  
...  
Keyword(s):  
Layered Double Hydroxides ◽  
Oxidation States ◽  
Secondary Amines ◽  
Primary Amines ◽  
Acid Dissolution ◽  
Oxidative Amination ◽  
Strong Function ◽  
Excellent Activity ◽  
High Yields ◽  
Double Hydroxides

<div> <p>The synthesis, characterization, and activity of Pd-doped layered double hydroxides (Pd-LDHs) for for acceptorless amine dehydrogenation is reported. These multifunctional catalysts comprise Brønsted basic and Lewis acidic surface sites that stabilize Pd species in 0, 2+, and 4+ oxidation states. Pd speciation and corresponding cataytic performance is a strong function of metal loading. Excellent activity is observed for the oxidative transamination of primary amines and acceptorless dehydrogenation of secondary amines to secondary imines using a low Pd loading (0.5 mol%), without the need for oxidants. N-heterocycles, such as indoline, 1,2,3,4-tetrahydroquinoline, and piperidine, are dehydrogenated to the corresponding aromatics with high yields. The relative yields of secondary imines are proportional to the calculated free energy of reaction, while yields for oxidative amination correlate with the electrophilicity of primary imine intermediates. Reversible amine dehydrogenation and imine hydrogenation determine the relative imine:amine selectivity. Poisoning tests evidence that Pd-LDHs operate heterogeneously, with negligible metal leaching; catalysts can be regenerated by acid dissolution and re-precipitation.</p> </div> <br>

ACID DISSOLUTION STUDIES USING BRAZILIAN SERPENTINITE ROCKS APPLIED MINERAL CARBONATION

2016 ◽  
Author(s):  
Kely Vieira ◽  
Kely Vieira ◽  
Gretta Larisa Aurora Arce Ferrufino ◽  
Ivonete Ávila ◽  
Carlos Manuel Romero Luna ◽  
...  
Keyword(s):  
Mineral Carbonation ◽  
Acid Dissolution ◽  
Dissolution Studies

Mass transfer into the liquid in turbulent flow at high Schmidt numbers. Dissolution of benzoic acid into aqueous solutions of glycerol from internal surface of the pipe

1981 ◽  
Vol 46 (7) ◽  
pp. 1566-1576
Author(s):  
František Vašák ◽  
Václav Kolář ◽  
Zdeněk Brož
Keyword(s):  
Mass Transfer ◽  
Benzoic Acid ◽  
Aqueous Solutions ◽  
Cross Section ◽  
Circular Cross Section ◽  
Internal Surface ◽  
Theoretical Relation ◽  
Acid Dissolution ◽  
Schmidt Numbers ◽  
Unified Description

Theoretical relation derived in the last study for calculation of the mass transfer coefficient in the region of not fully developed concentration profile at high Schmidt numbers has been verified experimentally. This experimental study has been devoted to measurements of the rate of benzoic acid dissolution into aqueous solutions of glycerol from the internal surface of the pipe of circular cross section in the range 933 ⪬ Sc ⪬ 225 000 and 5 000 ⪬ Re ⪬ 50 000. It has been possible to explain on basis of the theoretical model, the differences between the data of various authors and to obtain a unified description of the phenomena.

Mineral Density and Fluoride Content of in vitro Remineralized Lesions

1988 ◽  
Vol 67 (3) ◽  
pp. 577-581 ◽  
Author(s):  
Y. Jima ◽  
T. Koulourides
Keyword(s):  
Complete Recovery ◽  
Fluoride Content ◽  
Mineral Density ◽  
Acid Dissolution ◽  
Thin Sections ◽  
Partially Saturated ◽  
In Vitro Investigation ◽  
Bovine Enamel ◽  
Caries Lesions

This in vitro investigation studied the remineralization of experimental caries lesions in bovine enamel by use of three methods: (1) surface microhardness, (2) microradiography, and (3) abrasion biopsy for mineral density and fluoride content. The lesions were produced by a two-day exposure to 0.01 mol/L lactic acidlsodium hydroxide buffer partially saturated with 3.0 mmol/L Ca, 1.8 mmol/L P, in 1% CMC, at pH 4.0 and 37°C. The lesions were exposed to a remineralizing solution containing 3.0 mmol/L Ca, 1.8 mmol/L P, and 3 ppm F in 1% CMC at pH 7.0 and 37°C for two, six, and ten days, with solution changes every two days. The data derived from the three methods are presented in sequence from the baseline and at days two, six, and ten of the remineralizing treatment. Microhardness measurements showed hardness recoveries of 35.9, 78.9, and 87.5%, respectively. Microradiography suggested complete recovery with the ten-day remineralization. Abrasion biopsy of successive 10-μm layers to a depth of 100 μm indicated 15.2, 39.8, and 68.8% mineral density recoveries, with fluoride content of the surface layer increasing from a baseline of 300 ppm to 4600, 9000, and 9800 ppm F for the 2, 6, 10 days of remineralization, respectively. Subsequent acid-etching of thin sections from the ten-day-remineralized specimens showed that the fluoride-enriched remineralized area was more resistant to acid dissolution than was the underlying nonnal enamel.

Demystifying the Diffuse Vibrational Spectrum of Aqueous Protons Through Cold Cluster Spectroscopy

2021 ◽  
Vol 72 (1) ◽  
Author(s):  
Helen J. Zeng ◽  
Mark A. Johnson
Keyword(s):  
Double Resonance ◽  
Ion Traps ◽  
Cryogenic Cooling ◽  
Annual Review ◽  
Resonance Spectroscopy ◽  
Publication Date ◽  
Relaxation Dynamics ◽  
Acid Dissolution ◽  
Complex Species ◽  
Charge Translocation

The ease with which the pH is routinely determined for aqueous solutions masks the fact that the cationic product of Arrhenius acid dissolution, the hydrated proton, or H+(aq), is a remarkably complex species. Here, we review how results obtained over the past 30 years in the study of H+⋅(H2O) n cluster ions isolated in the gas phase shed light on the chemical nature of H+(aq). This effort has also revealed molecular-level aspects of the Grotthuss relay mechanism for positive-charge translocation in water. Recently developed methods involving cryogenic cooling in radiofrequency ion traps and the application of two-color, infrared–infrared (IR–IR) double-resonance spectroscopy have established a clear picture of how local hydrogen-bond topology drives the diverse spectral signatures of the excess proton. This information now enables a new generation of cluster studies designed to unravel the microscopic mechanics underlying the ultrafast relaxation dynamics displayed by H+(aq). Expected final online publication date for the Annual Review of Physical Chemistry, Volume 72 is April 2021. Please see http://www.annualreviews.org/page/journal/pubdates for revised estimates.

Silver ion catalysis in nitric acid dissolution of Ni3S2

1987 ◽  
Vol 18 (2) ◽  
pp. 195-205 ◽  
Author(s):  
Mulak Władysława
Keyword(s):  
Nitric Acid ◽  
Silver Ion ◽  
Acid Dissolution
Sign in / Sign up

Export Citation Format

Share Document