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Abstract  

Alkali metal ions are adsorbed on controlled porous glasses from basic solutions. Narrow porous glasses show a relatively high selectivity with adsorption decreasing in the series Cs, K, Na, Li.

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Conclusions  

From the results reported above it is evident that in most cases metal contamination, which is accidentally collected during the sampling of blood and the preparation of the serum, will be found in isolated protein fractions. The distribution of the trace metal contamination between protein and low molecular weight fractions appears to vary considerably from element to element. It will also depend on the total amount of the contaminant in relation to the size of the serum sample. Inspecting the metal elution peaks the conclusion might be reached that nearly symmetric peaks (Cu, Fe, Cr, Zn, Ga) indicate the formation of metal protein complexes. On the other hand, the distorted lanthanum peak suggests the presence of a different type of compound, possibly colloidal lanthanum hydroxide. Of the seven elements tested only manganese was not detected in the protein fraction. This is in agreement with the finding ofHoleysovska.4 This fact should simplify the determination of transmanganin.

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Abstract  

This paper describes some experimental results obtained at the extraction of sulfate solutions of U(VI), Mo(VI), V(V), Ce(IV), Zr(IV), Fe(III), Al(III) with a benzene solution of Primene JMT. The aqueous solutions consist of metal sulfates (or other metal salts) in the presence of sulfuric acid with a concentration range of 0–2.1 mol·dm–3, the concentration of amine in the organic phase being 0.1–0.3 mol·dm–3. The presence of various species of metal ions in the aqueous phase is considered and the equilibrium concentration of substances extracted in the organic phase is determined. On the basis of the results of chemical analysis (concentration of metals and sulfate ions) the composition of the prevailing complexes in the organic phase is proposed.

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Abstract  

In this study, we evaluated the reactivity of organic peroxides with metals. The effect of the metals on the decomposition of organic peroxides was measured using a differential scanning calorimeter (DSC). Results of DSC measurements showed that some organic peroxides have high reactivity with a gold plated cell. Especially, hydroperoxides were decomposed at lower temperature using the gold plated cell when compared to other type of cells. In order to evaluate the effect of metals on the hydroperoxides, the decomposition characteristics of cumenhydroperoxide (CHP) with metal powders were studied using a C80 calorimeter and the products were analyzed by a gas chromatograph. These results indicated that the radical reaction of CHP was catalyzed by the gold and the autocatalytic reaction of CHP was catalyzed by stainless steel (SUS) and hastelloy c (HC).

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Abstract  

Radiochemical separation methods have been applied for the neutron activation analysis of impurities in four high-purity refractory metals, Ta, Nb, W and Mo. Impurities in the metals of Ta, Nb and W can be separated into groups using anion exchange resin with HF and/or a mixture of HF acid and HCl, but those in Mo is done using both anion and cation exchange resins. The coprecipitation of U with Th in HF media is also investigated.

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Abstract  

The liquid-liquid extraction of about twenty ions with metal diethyldithiocarbamates in chloroform from citrate buffers of pH 2–6 and the most common inorganic acids has been studied. Several backextraction reagents have been examined: hydrochloric acid (1–12M), dilute nitric acid saturated with bromine and a mixture of concentrated hydrochloric acid and hydrogen peroxide. A short review of metal diethyldithiocarbamates as extraction reagents and a mathematical model for these extractions are also included.

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Abstract  

This procedure for metal powder preparation involves a combination of decomposition and reduction processes. The large mass loss through evolution of gaseous products leaves agglomerates of a fine-grained three-dimensional network of metal particle 0.2 to 1 μm in size.

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Abstract  

Effects of alkali metals, alkaline earth metals and some lanthanides on the adsorption of uranium on activated charcoal from aqueous solutions have been studied. These effects are correlated with the ionic radii of metal ions present in the solutions. Adsorption capacity, Xm and binding energy contant, K for uranium adsorption were calculated from the Langmuir equätion. The mean energy of adsorption, Es was calculated from adsorption energy constant, K, values determined from the Dubinin-Radushkevich isotherm equation. Wavelength dispersive X-ray fluorescence spectrometry was used for measuring the uranium concentration.

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Abstract  

Some new hydrazinium transition metal sulfite dihydrate complexes of the formula (N2H5)2M(SO3)2(H2O)2 where M=Fe, Co, Ni, Cu and Zn have been prepared and characterized by hydrazine and metal analyses, magnetic studies, electronic and infrared spectra and thermal analysis. The magnetic studies coupled with electronic spectra of iron, cobalt, nickel and copper complexes indicate their high spin octahedral nature. However the zinc complex is diamagnetic and show only the charge transfer transition. The infrared spectra shows that both the hydrazinium ions are coordinated to the metal ions, the sulfite ions are present as bidentate ligand. The simultaneous TG-DTA of these complexes were investigated in air and nitrogen atmospheres. In air, cobalt, nickel and zinc complexes give respective metal sulfate as the final residue while iron and copper complexes give the mixture of respective metal oxide and sulfate as the decomposition product. In nitrogen atmosphere respective metal sulfites are formed as the end residue.

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A.L. Page, F.T. Bingham , and A.C. Chang , in: N.W. Lepp (Ed.) Effect of Heavy Metal Pollution on Plants, Vol. 1, Applied Science, London, 1981, p. 72. Chang A

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