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1.
A method is proposed for the extraction and individual separation of trivalent gallium, indium and thallium from salicylate media using triphenylarsine oxide dissolved in toluene as an extractant. The optimum extraction conditions are evaluated and described. The extracted metal ions are stripped and estimated spectrophotometrically following complexation with 4-(2-pyridylazo) resorcinol. A possible mechanism of the extraction is discussed. The method permits rapid and precise individual separation of gallium (III), indium (III) and thallium (III) and is applicable to the analysis of alloy samples. 相似文献
2.
3.
A simple selective method is presented for the solvent extraction of yttrium from salicylate media by using triphenylphosphine
oxide. Yttrium is extracted quantitatively from 0.05 mol/l sodium salicylate solution at pH 4.5–5.0 using 1.8% triphenylphosphine
oxide dissolved in toluene as an extractant and can be subsequently stripped using water and determined spectrophotometrically
with Thoron-I. This precise and accurate method permits the separation of Y from Sc, Ti, V, Cr, Fe, Zr, Hf, Th and U from
binary mixtures and multi-component systems.
Received: 17 January 1995 / Accepted: 12 May 1995 相似文献
4.
Scandium can be extracted from 5.0 × 10–2 mol/l sodium salicylate solution, adjusted to pH 4.0–5.0 with 0.5% triphenylphosphine oxide dissolved in toluene as an extractant.
After stripping from the organic phase with 0.5 mol/l HCl it can be subsequently determined spectrophotometrically with Alizarin
Red S. The method permits a separation of Sc(III) from Ti(IV), V(V), Cr(VI), Fe(III), Y(III), La(III), Ce(III), Nd(III) and
Sm(III) in synthetic mixtures. The method is fast, simple and selective.
Received: 6 May 1996 / Revised: 21 July 1996 / Accepted: 25 July 1996 相似文献
5.
S. K. Das C. S. Kedari S. S. Shinde S. Ghosh U. Jambunathan 《Journal of Radioanalytical and Nuclear Chemistry》2002,253(2):235-240
The efficiency of tailor made immobilized Saccharomyces
cerevisiae(biomatrix) for the sorption of radionuclides 233U, 239Pu, 241Am, 137Ce, 144Cs, 103,106Ru and 90Sr from aqueous nitrate solutions at different pH was studied. Effect of ionic strength, anionic components, initial metal concentration and particle size of the biomatrix on the sorption of metal ions were investigated. At pH in the range of 1 to 2 more than 95% sorption of U, Pu, Am and Ce could be accomplished, while that of Ru was 65%. Sorption of Cs and Sr were negligible under similar conditions. The metal ion-biomatrix system for Pu, Am and Ce reached equilibrium within 60 minutes. In the case of U, equilibrium attained in 100 minutes. The presence of anionic components, Cl-, C2O4
2-, CH3COO-, NO3
- and SO4
2- (up to 0.5 mol.dm-3 of their individual concentration) in the aqueous solutions has no effect on the sorption of Pu by the biomatrix. Sorption of U, Pu, Am were observed in the presence of several cationic impurities such as Al, Be, Cd, Cr, Fe, Mn, Pb, Ce, Dy, Eu, Gd and Sm. Metal sorbed on the biomatrix could be leached out using 5 mol.dm-3 nitric acid. The I.R spectra of U bearing biomatrix suggest chemical interaction of uranyl ion with the biomatrix. 相似文献
6.
Triphenylarsine oxide is proposed as an extractant for the solvent extraction of uranium and thorium salicylates. The optimum extraction conditions are established by studying the various parameters such as pH, sodium salicylate concentration, triphenylarsine oxide concentration, diluents and shaking time. The probable extracted species as ascertained by logD-logC plots are UO2(Hsal)2·2TPAsO and Th(Hsal)4·2TPAsO. The method is simple, fast, precise and permits the determination of uranium and thorium in monazite sand samples. 相似文献
7.
S. Fuller J. Hopwood A. Rahman N. Shinde G. J. Tiddy G. S. Attard 《Liquid crystals》2013,40(3):521-529
Abstract We have studied the lyotropic liquid-crystalline behaviour of cationic surfactants containing a potentially thermotropic moiety, a terminal cyanobiphenyloxy group. Both mono-alkyl and mid-chain substituted dialkyl surfactants have been examined using optical microscopy and NMR spectroscopy. Incorporation of the cyanobiphenyloxy group destabilizes the hexagonal and bicontinuous cubic phases, with only an extensive lamellar region being observed. For the dialkyl surfactant there is a range of compositions where two lamellar phases co-exist, one water-rich and the second surfactant-rich. 相似文献
8.
An efficient, ligand- and metal-oxidant-free, one-pot, cascade aerobic oxidative, palladium-catalyzed, multicomponent reaction has been developed through isocyanide insertion of less active secondary amide and aromatic amine, which leads to 2-amino-substituted-4(3H)-quinazolinones. This approach proves to be one of the simplest methods for the synthesis of this class of valuable bioactive heterocyclic scaffolds. 相似文献
9.
Sridevi V. Shinde Sarika Sinha Prof. Dr. Kumaravel Somasundaram Prof. Dr. Ashoka G. Samuelson 《Chemistry (Weinheim an der Bergstrasse, Germany)》2012,18(39):12278-12291
Neutral half‐sandwich organometallic ruthenium(II) complexes of the type [(η6‐cymene)RuCl2(L)] ( H1 – H10 ), where L represents a heterocyclic ligand, have been synthesized and characterized spectroscopically. The structures of five complexes were also established by single‐crystal X‐ray diffraction confirming a piano‐stool geometry with η6 coordination of the arene ligand. Hydrogen bonding between the N? H group of the heterocycle and a chlorine atom attached to Ru stabilizes the metal–ligand interaction. Complexes coordinated to a mercaptobenzothiazole framework ( H1 ) or mercaptobenzoxazole ( H6 ) showed high cytotoxicity against several cancer cells but not against normal cells. In vitro studies have shown that the inhibition of cancer cell growth involves primarily G1‐phase arrest as well as the generation of reactive oxygen species (ROS). The complexes are found to bind DNA in a non‐intercalative fashion and cause unwinding of plasmid DNA in a cell‐free medium. Surprisingly, the cytotoxic complexes H1 and H6 differ in their interaction with DNA, as observed by biophysical studies, they either cause a biphasic melting of the DNA or the inhibition of topoisomerase IIα activity, respectively. Substitution of the aromatic ring of the heterocycle or adding a second hydrogen‐bond donor on the heterocycle reduces the cytotoxicity. 相似文献
10.
A. D. Shinde R. Acharya A. V. R. Reddy 《Journal of Radioanalytical and Nuclear Chemistry》2014,299(3):1287-1292
The k0-based internal monostandard instrumental neutron activation analysis (IM-INAA) method was applied for quantification of trace impurities in seven high purity aluminum samples used as fuel cladding in a research reactor. Samples along with BCS CRM 182 (Si–Al alloy) were irradiated in high flux reactor neutrons for 10–15 h. In situ detection efficiency, needed in concentration calculation ratio by IM-INAA, was obtained using gamma rays of activation products produced in the samples. Elemental concentration ratios obtained with respect to Fe (used as internal monostandard) were converted to absolute concentrations by determining concentration of Fe by relative method of NAA. Concentrations of ten trace elements (Sc, Cr, Co, Zn, Ga, La, Ce, Sm, W and Hf) including major element Fe were determined in this work. The method used is non-destructive in nature and does not need multielement standards. Results of IM-INAA were compared with those obtained by relative method of INAA and inductively coupled plasma atomic emission spectrometry (ICP-AES). Details of methodologies and results obtained by all methods are discussed and compared in the paper. 相似文献