Two types of ammonium uranyl nitrate (NH4)2UO2(NO3)4·2H2O and NH4UO2(NO3)3, were thermally decomposed and reduced in a TG-DTA unit in nitrogen, air, and hydrogen atmospheres. Various intermediate phases produced by the thermal decomposition and reduction process were investigated by an X-ray diffraction analysis and a TG/DTA analysis. Both (NH4)2UO2(NO3)4·2H2O and NH4UO2(NO3)3 decomposed to amo...

The alterations in the serum lipolytic activity of mice were studied under Uranyl nitrate (UN) intoxication. The lipemia produced as a result of UN intoxication was probed studying the alterations in the serum triacyl-glycerol-hydrolase (EC 3.1.1.3) activity. After an intraperitoneal injection of UN (10 mg/kg and 25 mg/kg), triacyl-glycerol-hydrolase (TAGH) activity was considerably enhanced. I...

Genetic engineering of radiation-resistant organisms to recover radionuclides/heavy metals from radioactive wastes is an attractive proposition. We have constructed a Deinococcus radiodurans strain harboring phoN, a gene encoding a nonspecific acid phosphatase, obtained from a local isolate of Salmonella enterica serovar Typhi. The recombinant strain expressed an approximately 27-kDa active Pho...

The increased urinary excretion of citrate following administration of sodium bicarbonate has been noted by many investigators (l-9). During the course of work on the effect of uranium on various metabolic processes we wished to ascertain whether the kidney poisoned by uranium would excrete citrate to the same extent that a normal kidney does after administration of sodium bicarbonate. Surprisi...

The example of phase transformation from a centrosymmetric space group at low temperature (LT) to a chiral space group at high temperature (HT) is reported, which was clearly resolved in a single-crystal-to-single-crystal manner in a 3D uranyl(vi) phosphonate compound [TMA][(UO2)2(1,3-pbpH)(1,3-pbpH2)] () (TMA(+) = tetramethylammonium cation; 1,3-pbpH4 = 1,3-phenylenebis(phosphonic acid)).

Both uranous and uranyl minerals are present in the Centennial unconformity-type U deposit situated in the SW Athabasca Basin, Canada. At least two generations of uraninite are present (disseminated and massive), often strongly altered to coffinite, followed by minor fibrous coffinite forming in veins. Uranyl minerals, mostly uranophane with minor haiweeite precipitating in veins and in hand sa...

recognize +4 and +6 as the main oxidation states for uranium and +4 as the only important oxidation state for thorium; appreciate that coordination numbers of >6 are the norm; be familiar with the main features of the chemistry of the other actinides, and appreciate the transition in chemical behaviour across the series; appreciate the importance of nitrate complexes; recognize the characterist...