Filters
Results 1 - 10 of 2931
Results 1 - 10 of 2931.
Search took: 0.027 seconds
Sort by: date | relevance |
AbstractAbstract
[en] A potentiometric study on the complex formation of Cu(II) and UO2(II) with dimethyl diisoxazolone (RH) in (1:1) water-dioxan at a constant ionix strength (μ=0.5) at 31 +- 0.5deg, has been made. The successive formation constants K1 and K2 have been determined following Irving and Rossotti method. Log K1 and log K2 are computed by graphical methods and are found to be 1.72, 1.61; 1.61,1.23 for Cu(II) and UO2(II) respectively. The acid dissociation constant ksup(*) of RH has also been determined in (1:1) water-dioxane as well as in (1:1) water-methanol are found to be pksup(*)=2.88 and 2.40 respectively. (author)
Primary Subject
Record Type
Journal Article
Journal
Journal of the Indian Chemical Society; v. 53(8); p. 779-780
Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
AbstractAbstract
[en] Voltammograms of uranocene in benzonitrile under an Ar atmosphere were recorded in studies to measure the controlled oxidation of the compound. The results indicated that cyclooctatetraene (COT) was librated during the electrolysis, and NMR data indicated that no more than 1/3 of all the COT ligand was librated as free COT. Combination of these data led to the conclusion that oxidation produced a dimeric or cluster product cation
Primary Subject
Record Type
Journal Article
Journal
Journal of the American Chemical Society; v. 100(3); p. 1012-1013
Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
Spencer, Liam P.; Schelter, Eric J.; Boncella, James M.; Yang, Ping; Gsula, Robyn L.; Scott, Brian L.; Thompson, Joe D.; Kiplinger, Jacqueline L.; Batista, Enrique R.
Los Alamos National Laboratory (United States). Funding organisation: US Department of Energy (United States)2009
Los Alamos National Laboratory (United States). Funding organisation: US Department of Energy (United States)2009
AbstractAbstract
[en] The dimeric bis(imido) uranium complex ({U(NtBu)2(I)(tBu2bpy)}2) (see picture; U green, N blue, I red) has cation-cation interactions between (U(NR)2)+ ions. This f1-f1 system also displays f orbital communication between uranium(V) centers at low temperatures, and can be oxidized to generate uranium(VI) bis(imido) complexes.
Primary Subject
Source
LA-UR--09-00903; AC52-06NA25396; Available from http://permalink.lanl.gov/object/tr?what=info:lanl-repo/lareport/LA-UR-09-00903
Record Type
Journal Article
Journal
Angewandte Chemie (International Edition); ISSN 1433-7851;
; (Issue Jan 2009); vp

Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
External URLExternal URL
AbstractAbstract
[en] The [(UO2)2F6-2H2O]2- ion has been observed in the Cs2[(UO2)2F6-2H2O] compound. It is similar to the (UO2)2F84- ion already found in the Cs4(UO2)2F8-2H2) and Rb4(UO2)2F8-2H2O complexes in which two of the fluorine atoms are replaced by two water molecules. Because of the existence of hydrogen bonds, these ions group themselves together in this structure to form chains
[fr]
L'ion [(UO2)2F6-2H2O]2- a ete mis en evidence dans le compose Cs2[(UO2)2F6-2H2O]. Il ressemble a l'ion (UO2)2F84- deja trouve dans les complexes Cs4(UO2)2F8-2H2) et Rb4(UO2)2F8-2H2O dans lequel deux des atomes de fluor ont ete remplaces par deux molecules d'eau. A cause de l'existence de liaisons hydrogene, ces ions s'associent entre eux dans la structure pour former des chainesOriginal Title
Mise en evidence de l'ion complexe bis-(μ-fluoro)-bis[eta-aquo-difluoro-dioxouranium (VI)]2- [(UO2)2F6-2H2O]2- dans le compose Cs2(UO2)2F6 - 2H2O]
Record Type
Journal Article
Journal
C. R., Ser. C; v. 281(14); p. 593-596
Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
AbstractAbstract
[en] In this work, the PNP ligand ([2-(Ph2P)C6H4]2N) has been shown to be flexible, hemi-labile, and capable of stabilizing low- and high-valent uranium species. The bis(PNP) framework is then a valuable alternative to the (C5Me5) ligand set, offering distinct structures and reaction patterns. (O.M.)
Primary Subject
Source
Available from doi: http://dx.doi.org/10.1002/anie.200900504; 11 refs.
Record Type
Journal Article
Journal
Angewandte Chemie (International Edition); ISSN 1433-7851;
; v. 48(no.27); p. 4898-4899

Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
External URLExternal URL
AbstractAbstract
[en] The Cp3UR- anions 1 react with organic halides R'X (R or R' = Me, nPr, iPr, nBu, allyl, Bz) to give the Cp3UR and Cp3UR' compounds. The product distribution indicates that the species Cp3U(R)(R') should be intermediates in these oxidation reactions. 21 refs
Record Type
Journal Article
Journal
Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
AbstractAbstract
[en] A multisyringe flow injection analysis method for the determination of uranium in water samples was developed. The methodology was based on the complexation reaction of uranium with arsenazo (III) at pH 2.0. Uranium concentrations were spectrophotometrically detected at 649 nm using a light emitting diode. Under the optimized conditions, a linear dynamic range from 0.1 to 4.0 μg mL-1, a 3σ detection limit of 0.04 μg mL-1, and a 10σ quantification limit of 0.10 μg mL-1 were obtained. The reproducibility (%) at 0.5, 2.5, and 4.0 μg mL-1 was 2.5, 0.9, and 0.6%, respectively (n = 10). The interference effect of some ions was tested. The proposed method was successfully applied to the determination of uranium in water samples. (author)
Primary Subject
Secondary Subject
Source
25 refs.
Record Type
Journal Article
Journal
Journal of Radioanalytical and Nuclear Chemistry; ISSN 0236-5731;
; CODEN JRNCDM; v. 281(3); p. 433-439

Country of publication
ACTINIDE COMPLEXES, ACTINIDES, AROMATICS, ARSONIC ACIDS, AZO COMPOUNDS, COMPLEXES, ELEMENTS, HYDROGEN COMPOUNDS, HYDROXY COMPOUNDS, METALS, ORGANIC ACIDS, ORGANIC ARSENIC COMPOUNDS, ORGANIC COMPOUNDS, ORGANIC NITROGEN COMPOUNDS, ORGANIC SULFUR COMPOUNDS, OXYGEN COMPOUNDS, PHENOLS, POLYPHENOLS, REAGENTS, SULFONIC ACIDS
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
Termes, S.C.
Georgetown Univ., Washington, D.C. (USA)1977
Georgetown Univ., Washington, D.C. (USA)1977
AbstractAbstract
[en] Redox behavior and spectroscopic properties of four heteropoly anions of uranium(IV) have been studied, namely: (a) dodecamolybdouranate(IV), [UMo12O42]8-, (b) decatungstouranate(IV), [UW10O36]8-, (c) bis-(undecatungstrophosphato)uranate(IV), [U(PW11O39)2]10- and (d) bis-(undecatungstosilicato)-uranate(IV), [U(SiW11O39)2]12-. Cyclic voltammetry of the anions in aqueous solutions showed that the complexes [UMo12O42]8-, [U(PW11O39)2]10-, and [U(SiW11O39)2]12- were oxidizable to their U(V) analogues. The redox process was found to be pH dependent for [UMo12-O42]8- and [U(SiW11O39)2]12-. The anions [UMo12O42]8- and [U(PW11O39)2]10- can be oxidized electrolytically to stable U(V) isomorphs. The U(V) complexes can be reduced to their corresponding U(IV) species. The anion [U(PW11O39)2]10- was isolated as potassium-organic cation double salts which are soluble in a variety of organic solvents. In non-aqueous solutions, [U(PW11O39)2]10- can be readily oxidized to the U(V) complex and these solutions of the oxidized anion were found to be indefinitely stable. The electronic absorption spectra of the four heteropoly anions of U(IV) manifested clearly the crystal field effects on the U(IV) chromophore caused by the different site-symmetries provided by the heteropoly ligand. A square-anti-prismatic coordination of U(IV) in [U(PW11O39)2]10- and [U-(SiW11O39)2]12- was inferred from electronic absorption spectra. In non-aqueous media, the spectrum of [U(PW11O39)2]9- was characterized by a narrow absorption band at 6.51 kK which was assigned to the pure electronic transition of the U(V) chromophore
Source
1977; 188 p; University Microfilms Order No. 77-17,770; Thesis (Ph. D.).
Record Type
Report
Literature Type
Thesis/Dissertation
Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
AbstractAbstract
[en] In clean, one-pot procedures, the uranium complex reductively cleaves azides and azo compounds to generate bis(imido) derivatives. This unusual reaction has not been observed previously in either the actinide series or with a metallocene complex. (orig.)
Primary Subject
Source
This record replaces 29059219
Record Type
Journal Article
Journal
Angewandte Chemie (International Edition); ISSN 1433-7851;
; v. 37(7); p. 959-960

Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
AbstractAbstract
No abstract available
Original Title
Estabilidad quimica del uranio tetravalente en soluciones organicas
Primary Subject
Source
21. Mexican Congress of Pure and Applied Chemistry; Oaxaca, Oaxaca (Mexico); 9-13 Sep 1986; Published in summary form only.
Record Type
Journal Article
Literature Type
Conference
Journal
Country of publication
Reference NumberReference Number
INIS VolumeINIS Volume
INIS IssueINIS Issue
1 | 2 | 3 | Next |