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1.
The diorganotin(IV) and triorganotin(IV) derivatives R2SnA (R = Me, n-Pr, n-Bu, n-Oct) and (R3Sn)2A [R = Me, Ph, cyclohexyl (Cyh); A = an anion of diphenic acid] have been prepared and characterized by elemental analysis, IR, 1H and 13C NMR spectroscopies. Tetrahedral tin forms a part of a diphenate cyclic ring in the diorganotin complexes with unidentate carboxylates, which have further been used for the synthesis of cyclic acid anhydrides. The soluble dinuclear triorganotin complexes (Me, Ph) possess symmetrically bonded carboxylates while the less soluble compound (Cyh3Sn)2A has two asymmetrically bonded carboxylates. All have a trigonal bipyramidal structure with R3Sn units remote from each other. 相似文献
2.
《Polyhedron》1986,5(3):743-752
The breakdown of polymeric plutonium(IV) hydroxide (plutonium colloid) by cerium(IV) has been studied spectrophotometrically by monitoring the formation of plutonium(VI). Reaction rate variations were studied with changes in cerium(IV), acid and plutonium colloid concentrations. A reaction mechanism involving the formation of [Ce2O(OH)2]4+ and its reaction with the polymer surface to produce two plutonium(V) ions is postulated to explain the observed kinetic data, in particular the maximum in the reaction rate at around 0.3 M nitric acid. 相似文献
3.
The preparation and the properties of the hexacyanopalladium(IV) acid (H3O)2[Pd(CN)6] and of a number of metal hexacyanopalladates(IV) are described. UV, IR and Raman spectra are reported, force constants have been calculated and the bonding properties are discussed. K2[Pd(CN)6] crystallizes in a hexagonal lattice; a = 7.42, c = 6.65 Å, Z = 1. 相似文献
4.
M. Ejaz 《Journal of Radioanalytical and Nuclear Chemistry》1977,36(2):409-417
Trace level cerium has been oxidized to the quadrivalent state with potassium dichromate and shown to be preferentially extracted
from very dilute mineral acid solutions and also from moderate nitric acid media by 0.1M solutions of 4-(5-nonyl)pyridine
oxide and trioctylamine oxide dissolved in xylene. The dependence of extraction on the type of N-oxide, acid concentration
and the N-oxide concentration has been investigated. The influence of the concentration of salting-out agents is described.
Separation factors for a number of metal ions relative to cerium(IV) are reported for 0.1 M 4-(5-nonyl)pyridine oxide/xylene-0.1M
sulphuric acid system. The ratio of the D for Ce(IV) to that of Ce(III) is greater than 105, and the D for Ce(IV) is much greater than that for thorium(IV). Separation of cerium(IV) from thorium has been achieved
from 0.1M sulphuric acid solutions using 0.1M 4-(5-nonyl)pyridine oxide/xylene as an extractant. 相似文献
5.
R. M. Sawant N. K. Chaudhuri S. K. Patil 《Journal of Radioanalytical and Nuclear Chemistry》1990,141(2):295-306
The extraction behaviour of Th(IV) and U(VI) in extraction chromatography has been investigated on the basis of partition and infrared studies. The stationary phase was purified undiluted TBP supported on Amberlite XAD-4 and the mobile phase was nitric acid. The results have shown that the equilibria for the extraction of Th(IV) and U(VI) by the TBP/XAD-4 resin agreed very closely with those in solvent extraction. 相似文献
6.
Alexandra T. Shulyak Evgeniy O. Bortnikov Alexey S. Kubasov Nikita A. Selivanov Alexey A. Lipengolts Andrey P. Zhdanov Alexander Yu. Bykov Konstantin Yu. Zhizhin Nikolai T. Kuznetsov 《Molecules (Basel, Switzerland)》2021,26(12)
The interaction of hafnium(IV) salts (oxide-dichloride, chloride, and bromide) with nitrilotriacetic acid (NTA), diethylenetriamminepentaacetic acid (DTPA), 1,2-diaminocyclohexanetetraacetic acid (CDTA), 1,3-dipropylmino-2-hydroxy N,N,N′,N′-tetraacetic acid (dpta), and N-(2-hydroxyethyl)ethylenediamine triacetic acid (HEDTA) has been studied. The corresponding complexes Na2[Hf(NTA)2]·3H2O (1), Na[HfDTPA]·3H2O (2), [HfCDTA(H2O)2] (3), and Na[Hf2(dpta)2]·7.5H2O·0.5C2H5OH (4) have been isolated and characterized and their structures have been determined by single crystal X-ray diffraction. Biological studies of [HfCDTA(H2O)2] have shown that in 5% glucose solution this complex has low toxicity and good contrasting ability. 相似文献
7.
Hydroxoplatinic Acid and its Ammonium Salt Single crystals of platinic acid H8PtO6 and its ammonium salt have been prepared. The crystal structure of H8PtO6, monoclinic, space group C2/c—C2h6, with a = 847.0, b = 719.5, c = 745.1 pm, β 93.54° and Z = 4, contains molecules which are connected by strong hydrogen bonds with oxygen-oxygen distances of 259 to 266 pm. The ammonium salt has a rhombohedral lattice with hexagonal lattice constants of a = 705.7, c = 1182.0 pm, and Z = 3. 相似文献
8.
Ram Chand Paul Surinder Kumar Gupta Veena Goyal Sham Kumar Vasisht 《Monatshefte für Chemie / Chemical Monthly》1977,108(5):1019-1025
Oxozirconium(IV) alkoxides of the type ZrO(OR)2·ROH and ZrOCl(OR)·2 ROH, where R is methyl, ethyl, and isopropyl, and ZrO(OCMe
3)2·0.5Me
3COH and ZrOCl(OCMe
3)·1.5Me
3COH have been prepared by the reaction of dichloroxozirconium(IV)-2-acetic acid with corresponding alcohols in the presence of appropriate amounts of piperidine. The alkoxides have been isolated and characterised through infrared, thermal and conductance studies. 相似文献
9.
M. S. Nagar P. B. Ruikar M. S. Subramanian 《Journal of Radioanalytical and Nuclear Chemistry》1986,99(1):109-119
The precipitation behaviour of basic plutonium(IV) compounds from dilute nitric acid medium with aliphatic dicarboxylic acids has been investigated. Unlike plutonium(IV) oxalate, which is precipitated in acid medium (1–4M), the higher dicarboxylates precipitate in 0.9–2.5 pH range and their elemental analysis indicate Pu/dicarboxylate ratio of 11. The mode of formation, composition, solubility and thermal degradation behaviour for plutonium(IV) hydroxosuccinate has been studied. The hydroxy group determination by kinetic titration using fluoride complexing revealed that the compound has a Pu:OH ratio of 11 and determination of bridging oxygen group gave a Pu:O ratio of 10.5 suggest its formation as hydroxysuccinate having an oxobridged formula. 相似文献
10.
Zu-Ming Zhou Yong-Xia Sun Shao-Ning Yu Hui-Fang Du 《Journal of Radioanalytical and Nuclear Chemistry》1996,214(5):369-379
The kinetics of solvent extraction of U (IV), Th (IV) and U (VI) from nitric acid solution with tributyl phosphate (TBP) in kerosene and cyclohexane have been studied using the single drop technique. The effects of concentrations of U (IV), Th (IV), U (VI), nitric acid, nitrate, TBP and temperature on the extraction rates of U (IV), Th (IV) and U (VI) have been examined. The mechanisms for the three extraction processes are discussed. 相似文献
11.
S. K. Milonjić Dj. M. Čokeša R. V. Stevanović 《Journal of Radioanalytical and Nuclear Chemistry》1992,158(1):79-90
Adsorption of uranium(VI) and zirconium(IV) from aqueous nitric acid solution on silica gel has been investigated under dynamic conditions. The influence of temperature, nitric acid concentration (pH), and solution flow rates was studied. If the nitric acid concentration in the solution is higher than 0.05 mol/l, then it is possible to achieve separation of uranium(VI) and zirconium(IV) by passing the solution through a column filled with silicagel. 相似文献
12.
Horst Müller 《Analytical and bioanalytical chemistry》1969,247(3-4):145-149
The ions ReBrnCl 6?n 2? (0?n?6) and OsBrnCl 6?n 2? , respectively, ReO4 ? and Br? have been separated on cellulose using the thin-layer chromatographic technique with 3.2 M sulphuric acid as the mobile phase. 相似文献
13.
Summary Amperometric ascorbimetric determinations of cerium(IV) and ferric iron have been carried out at 50°C with two polarized electrodes at 200 and 100 mV respectively. The results obtained are fairly accurate and precise within ±1.0 per cent. A simple method for successive determination of cerium and iron has been developed; and conditions for such estimations have been established. At an acidity of 2.5 M with respect to sulphuric acid, it is possible to ward off the reduction of ferric iron and thereby cerium(IV) is successfully titrated with ascorbic acid in this medium. After completion of the reaction and then lowering the acid concentration to pH 1.5 with aid of ammonium hydroxide, FeIII is titrated with standard ascorbic acid yielding good results. 相似文献
14.
Gómez-Alcántara Mdel M Cabeza A Olivera-Pastor P Fernández-Moreno F Sobrados I Sanz J Morris RE Clearfield A Aranda MA 《Dalton transactions (Cambridge, England : 2003)》2007,(23):2394-2404
This article reports the hydrothermal synthesis and characterization of two new series of porous tin(IV) phosphonophenoxyphenylphosphonates with controlled pore size distributions, using as precursor the 4-(4'-phosphonophenoxy)phenyl phosphonic acid, [H2O3P-C6H4]2-O. Supermicroporous solids (S(BET), 300-400 m2 g(-1)) were obtained employing n-alcohol (C1-C6)-water mixtures (solvents ratio 1 : 1), in the presence of hydrofluoric acid. X-Ray powder diffraction shows that these compounds are semi-crystalline and the local environments around the phosphorus and tin elements have been studied by 31P and 119Sn MAS-NMR spectroscopy, respectively. The microstructure (particle sizes and shapes) of these phosphonates has been analyzed by scanning and transmission electron microscopy. This study shows that the microstructures of single-ligand (for instance tin(IV) phenylphosphonate) and cross-linked tin(IV) bisphosphonates are different. Tin(IV) phenylphosphonate crystallizes as micron-sized spheres, theta approximately 1-2 microm, formed by the aggregation of nanospheres, whereas tin(IV) bisphosphonates crystallize as microparticles larger than 20 microm. The textural properties of these porous solids were characterized by N2 and CO2 sorption isotherms. The key result of this work is that maxima of pore size distributions smoothly shift from 12 to 16 angstroms upon increasing the chain length of the alcohol. The microporosity of tin(IV) bisphosphonates is compatible with a double role played by the phosphonate groups acting as a pillar between adjacent layers and as a component of the hybrid organic-inorganic layers. 相似文献
15.
A simple indirect titrimetric determination of uric acid with manganese(IV) sulfate has been proposed. The method is stoichiometric and accurate and can be conveniently adapted for the assay of urinary uric acid. 相似文献
16.
The extraction of hafnium(IV) tracer by N-benzoyl-n-phenylhydroxylamine (BPHA) from 1M perchloric acid has been investigated and stability constants have been calculated for the complexes Hf(BPHA)(i)((4-i)+) (i = 1cdots, three dots, centered4). It was found that variation of perchlorate concentration in the range 0.5-2.0M at constant acidity has no effect on the distribution of hafnium. 相似文献
17.
P. D. Mithapara V. K. Manchanda P. R. Natarajan 《Journal of Radioanalytical and Nuclear Chemistry》1984,83(2):301-307
Octylphenyl acid phosphate, the commercially available mixture of monooctylphenylphosphoric acid (MOPPA) and dioctylphenylphosphoric acid (DOPPA) in xylene medium has been employed as an extractant for distribution studies on Pu(IV) in different mineral acids including phosphoric acid. It was found possible to extract Pu quantitatively from an acid mixture comprising 2.5M H3PO4, 0.75M H2SO4 and 0.5M HNO3. Quantitative stripping was observed with a mixture of 0.25M oxalic acid and 0.2M ammonium oxalate.Parts of this work have been reported at symposie (Refs1,2) 相似文献
18.
Differential pulse polarographic methods for the determination of selenium(IV) and tellurium(IV) in nitric acid medium are described. The peak current is maximal when 0.25M nitric acid medium is used, the DPP peaks for Se(IV) and Te(IV) being at -0.54 and -0.8 V vs. Ag/AgCl respectively. The peak current is a linear function of selenium concentration over three ranges, 5.1 x 10(-6)-1.3 x 10(-5), 1.27 x 10(-5)-1.27 x 10(-4) and 1.27 x 10(-4)-7.60 x 10(-4)M Se(IV), with different slopes. The plot for Te(IV) is linear over the range 0.78 x 10(-6)-9.40 x 10(-5)M. 相似文献
19.
《Journal of organometallic chemistry》1987,321(1):15-25
Complexes of the general formula R3SnX, where X is the anion of benzoic acid, o-, m-, p-amino- or N-phenyl-o-amino-benzoic acid, have been prepared and characterised. A combination of molecular weight, infrared, 1H NMR and 119Sn Mössbauer measurements show that, the amino-nitrogen atoms are not coordinated to tin. When R = phenyl or cyclohexyl, the compounds are monomeric and four-coordinate, and when R is alkyl (Me, Prn, Bun) they are monomeric and five-coordinate, with a bidentate carboxylate in the equatorial position of a trigonal bipyramidal structure. 相似文献
20.
The extraction of Zr(IV) by 2-thenoyltrifluoroacetone (TTA) in carbon tetrachloride from aqueous hydrochloric acid solutions
is a slow process. The addition of a neutral extractant, di-n-pentyl sulfoxide (DPSO) enhances considerably the rate as well
as the percentage of extraction. The species extracted appears to be ZrCl2(TTA)2·2 DPSO. An increase in temperature results in a further increase in the rate and percentage of extraction. Studies have also
been carried out on the extraction of the metal by mixtures of various neutral extractants. Thermodynamic parameters associated
with the formation of the synergistic adducts have been evaluated. 相似文献