The hydrolysis of uranyl-, Nd- and Ce-cations, induced by thermal decomposition urea was investigated the impact content experiment temperature on reaction kinetics evaluated. Uranyl precipitated as ammonium diuranate (ADU) with varying stoichiometry. Nd(III) Ce(III) showed comparable pH evolutions lanthanide carbonate hydroxide (LnCO3OH) products were identified, whereas Ce(IV) hydrolysed at l...

Carbonate anion exchange reactions with water in the uranyl-carbonate and calcium-uranyl-carbonate aqueous systems have been investigated using computational methods. Classical molecular dynamics (MD) simulations with the umbrella sampling technique were employed to determine potentials of mean force for the exchange reactions of water and carbonate. The presence of calcium counter-ions is pred...

The parameters to prepare U3O8 by calcination from ammonium uranyl carbonate were optimized by using response surface methodology. A quadratic equation model for the value of total uranium and U4+ of triuranium octaoxide was built and the effects of main factors and their corresponding relationships were obtained. The statistical analysis of the results indi...

-Well-characterized American Petroleum Institute clay standards, source clays from The Clay Minerals Society, and other secondary minerals were used to determine the effects of U concentration, temperature, and solution composition on U-sorption properties. Uranium concentrations ranged from about 1.00 x 10 -4 M to 4.00 x 10 7 M, temperatures from 5 ~ to 65~ and solution compositions containing...

Ambient and liquid helium temperature laser-induced time-resolved uranyl fluorescence spectroscopy was applied to study the speciation of aqueous uranyl solutions containing carbonate and phosphate and two porewater samples obtained by ultracentrifugation of U(VI)-contaminated sediments. The significantly enhanced fluorescence signal intensity and spectral resolution found at liquid helium temp...

Contamination of soils with depleted uranium (DU) from munitions firing occurs in conflict zones and at test firing sites. This study reports the development of a chemical extraction methodology for remediation of soils contaminated with particulate DU. Uranium phases in soils from two sites at a UK firing range, MOD Eskmeals, were characterised by electron microscopy and sequential extraction....

The reduction of formaldehyde by ammonium carbonate was examined in cadavers and in vitro. Formaldehyde concentrations in the air (10 cm above human cadavers) and in various cadaveric tissues were measured with or without perfusion of ammonium carbonate solution into formaldehyde-fixed cadavers. Air samples were monitored using Kitagawa gas detector tubes. For measurement of formaldehyde in tis...

easily prepared nanozno was found to be as an efficient catalyst in the synthesis of 1,4-dhps via four-component reaction of 1,3-dicarbonyls, aldehydes and ammonium carbonate in water at 60 °c. the prepared nanozno was characterized by xrd and ft-ir analysis, while the determined specific surface area of nano catalyst by bet method was 33 m2/g.

Formaldehyde gas, generated by the depolymerization of paraformaldehyde and in the presence of water vapor, has been traditionally used for biological decontamination of equipment and spaces utilized for research with a susceptible biological agent. This gas has often been neutralized with ammonia gas, generated by the thermal decomposition of ammonium bicarbonate or ammonium carbonate. An elem...