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1.
N,N,N,N-tetrabutylsuccinylamide (TBSA) was synthesized, characterised and used for the extraction of U(VI) and Th(IV) from nitric acid solutions into n-dodecane. Extraction distribution coefficients of U(VI) and Th(IV) as a function of aqueous nitric acid concentration, extractant concentration and temperature have been measured and found that n-dodecane as diluent was superior to 50% 1,2,4-trimethyl benzene (TMB) and 50% kerosene, (OK) system for extraction of U(VI) and Th(IV). The compositions of extracted species, equilibrium constants and enthalpies of extraction reactions have also been calculated. The formation of the 121 complex of uranyl(II) ion or the 141 complex of thorium(IV) ion, nitrate ion and TBSA and extracted species was further confirmed by the IR spectra of saturated extract of U(IV) and Th(IV).  相似文献   

2.
Experimental results are reported on the determination by thermogravimetry of the iron(II) content of the NiZnCo ferrite with the molar ratio Fe2O3NiOZnOCoO=59.019.520.51.0.  相似文献   

3.
Zusammenfassung Die Flüssig-flüssig-Extraktion des Goldes als Polyäthylenglykoloxonium-saccharino-aurat(III) erlaubt seine Trennung von Palladium, Platin, Arsen, Antimon, Mangan, Nickel, Eisen, Kobalt und anderen Metallen bis zu den Verhältnissen AuPdPtAsMnSbNiFeCo =110060070010001500100002000050000. Trennungen Au/Pb sind beim Verhältnis 150000 mit der photometrischen Meßgenauigkeit durchführbar. Das Gold wird in der nichtwäßrigen Phase bei 315 nm photometrisch bestimmt.Teil II: Ziegler, M., u. H.-D. Matschke: diese Z. 184, 166 (1961).  相似文献   

4.
The complexes of Co(II) and Ni(II) with nitroso-R-salt are studied by conductometric titration and spectrophotometric methods in buffer solutions of differentpH. The study proved the possible formation of (11), (12) and (13) complexes for Co(II) while Ni(II) forms (11) and (12) complexes (metal:ligand) only. The factors affecting complex formation are established and the formation constants of the complexes are evaluated. The ir spectra of the solid complexes with -nitroso--naphthol revealed that the ligand exhibits the nitrosophenol structure and that the reaction takes place through proton displacement from the OH-group.
Spektrophotometrische Studie zur Reaktion von Co(II) und Ni(II) mit Nitroso-R-Salz und -Nitroso--naphthol
Zusammenfassung Es wurden die Komplexe von Co(II) und Ni(II) mit Nitroso-R-Salz mittels konduktometrischer und spektrophotometrischer Methoden in Puffer-Lösungen mit verschiedenempH untersucht. Für Co(II) wurden (11)-, (12)- und (13)-Komplexe gefunden, während für Ni(II) lediglich (11)- und (12)-Komplexe (Metall:Ligand) festgestellt werden konnten. Die Faktoren, die die Komplexierung bestimmen, werden diskutiert und die Komplexbildungskonstanten wurden bestimmt. Die IR-Spektren der Komplexe mit -Nitroso--naphthol zeigen, daß der Ligand in der Nitrosophenol-Form vorliegt und daß die Reaktion über eine Protonenverschiebung von der OH-Gruppe verläuft.
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5.
Composites of cuprates of La(III) and Ba(II) were obtained by decomposing mixtures of oxalates of La(III), Ba(II) and Cu(II) prepared in 111 and 123 mol proportions respectively and sintering the oxide products at 1173 K. Reactions studied by TG, DTA and XRD techniques revealed the following features: (i) Decomposition of oxalates of La(III) and Ba(II) is drastically affected in mixtures. Decomposition temperature of organic part in the former (111) is shifted by 100 K while that of BaCO3 in the case of latter (123) is shifted by 400 K towards lower temperature side. (ii) All exothermic peaks on DTA traces of both the mixtures are allotted to the decomposition of oxalates to Cu2O, La2O2CO3 and BaCO3 phases while endothermic peaks around 863 and 1083 K are assigned for BaCuO2 and La2CuO4 phases respectively in the case of former (111) and endothermic peaks at about 1068, 1136 and 1213 K are correlated with BaCuO2, a composite of La2O3, La2CuO4 and La0.5Ba0.5CuO3– (0.5) phases and LaBa2Cu3O7– (0) phase respectively in the case of latter (123) and (iii) Lines of all cuprate compounds appear in XRD patterns of those samples preheated at temperatures 873 K. The following reaction is proposed in the case of 123 mixture: Authors are deeply thankful to the Authorities of Department of Atomic Energy (DAE), Goverment of India, for providing the funds for research project and to Professor A. V. Phadke, Department of Geology, University of Poona, for the valuable discussion.  相似文献   

6.
Zusammenfassung Die extraktiv-photometrische Bestimmung von Gold bei 325 nm als Tetrahydrofuranoxonium-Tetrachloroaurat(III) umfaßt im Bereich 20–250 g Gold folgende Spezifitäten: Au3+ Cu2+ Ni2+ Cr3+ Fe3+ Co2+ Pt4+ Pd2+ Rh3+ = 1 160000 120000 120000 80000 40000 6500 5000 1500.
Extractive-photometric determination of gold using tetrahydrofuran
Summary Extractive-photometric measurement of Tetrahydrofuranoxonium-Tetrachloroaurat(III) near 325 nm permits determination of Gold within the range 20–260 g including the specif ities Au3+ Cu2+ Ni2+ Cr3+ Fe3+ Co2+ pt4+ pd2+ Rh3+ = 1 160000 120000 120000 80000 40000 6500 5000 1500.
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7.
    
Zusammenfassung Calcium erleichtert die Reduktion des Kupfer(II)-äthylenglykol-bis-(2-aminoäthyläther)-N,N,N,N-tetraacetat-Chelats und gibt eine neue Welle bei positiverem Potential. Die Eigenschaften der Reduktionswelle und der Elektrodenvorgang werden untersucht. Die Methode wird erfolgreich auf die Calciumbestimmung in Gegenwart von Magnesium angewandt, wobei das Verhältnis CaMg bis 110 betragen darf.
Polarographic study on the substitution reduction of copper(II)-ethyleneglycol-bis-(2-aminoethylether)-N,N,N,N-tetraacetate chelate in the presence of calcium ion and its application to the determination of calcium in the presence of magnesium
Summary Calcium ion facilitates the reduction of copper(II)-ethyleneglycol-bis-(2-aminoethylether)-N,N,N,N-tetraacetate chelate and provokes a new wave at a more positive potential. The properties of the reduction wave and the electrode process are investigated. The method is successfully applied to the determination of calcium in the presence of magnesium up to a ratio of CaMg=110.
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8.
Summary The copper(II), cobalt(II) and nickel(II) chloride and bromide complexes with the ligands 2-(2-quinolyl)-benzimidazole (qbi), 2-(4-methyl-2-quinolyl)benzimidazole (mqbi), 2-(4-methyl-8-quinolyl)benzothiazole (m'q'bt) have been prepared and characterized by analytical methods, magnetic measurements as well as by electronic absorption, e.s.r. and far i.r. spectra. Complexes of various stoichiometries have been isolated, namely MLX2 (all cobalt complexes with exception of the bromide qbi complex; the chloride and bromide nickel m'q'bt and mq'bt complexes), ML2X2 (M=Co,L=qbi and X=Br; M=Ni, L=mqbi, X=Cl or Br, M=Ni, L=qbi, X=Cl) and ML3X2(M=Ni, L=qbi or mqbi, X=Br). The cobalt ion has a distorted tetrahedral N2X2 coordination in all the CoLX2 complexes, whereas Co(qbi)2Br2 is six-coordinate. The following conclusions may be drawn for the nickel complexes: in those with the 11 metal-to-ligand molar ratio the metal ion is four-or five-coordinate; in those with the 12 and 13 ratios the metal ion is hexa-coordinate, being essentially bound to four nitrogen atoms with halogens, oxygens from water or methanol or nitrogen atoms (from the third ligand) occupying the axial positions.  相似文献   

9.
    
Zusammenfassung Unter Benutzung der Kombinationen von bindemittelfreiem Kieselgel mit Tetrachlorkohlenstoff-Dichlormethan-EssigsÄureÄthylester-AmeisensÄure (70501510) und von acetyliertem Polyamid mit Tetrachlorkohlenstoff-EssigsÄureÄthylester-Äthanol (10052) wurde das dünnschichtchromatographische Verhalten von zehn alkyl- und arylsubstituierten Harnstoffverbindungen untersucht. Die erstere Anordnung erwies sich auch für die Trennung der CarbamidsÄureester niederer Alkohole als geeignet.
Summary Using a combination of binder-free silica gel with carbon tetrachloridedichloromethane-ethyl acetate-formic acid (70501510) and of acetylated polyamide with carbon tetrachloride-ethyl acetate-ethanol (10052), the behaviour of alkyl- and aryl-substituted urea compounds in TLC has been examined. The first combination showed also satisfactory results when used for the separation of carbamic acid esters of lower alcohols.
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10.
Simple, precise, sensitive, and highly selective methods for the separate determination of iron(III) and cobalt(II) and for the simultaneous determination of both metal ions are described. Iron(III) and cobalt(II) react with thiocyanate in the presence ofN-phenylcinnamohydroxamic acid (PCHA) to form pinkish red and blue coloured complexes, respectively. Both the iron(III) and cobalt(II) complexes having stoichiometric composition of 122 (FeSCNPCHA) and 14 (CoSCN), respectively, are quantitatively extractable into ethylacetate from 0.5–1.5 M hydrochloric acid solutions. The spectra of iron(III) and cobalt(II) complexes in the visible region exhibit absorption maxima at 495 and 625 nm, respectively. The coloured systems obey Beer's law in the concentration range of 0.2–4.0g/ml of iron and 2–40g/ml of cobalt. The effects of foreign ions and of various experimental parameters were studied to establish the optimum conditions for the extraction and determination of iron and cobalt. The methods have been applied successfully to the analysis of blood, vitamin B12, and standard steels for iron and cobalt.  相似文献   

11.
The formation of mixed ligand complexes of the title metal ions with 1,10-phenanthroline (Phen) or 2,2-bipyridyl (Bipy) in presence of histidine (His) has been studied pH-metrically. The stepwise formation of 111 mixed ligand complexes has been inferred from the potentiometric titration curves. Initially, a 11 metal—Phen or—Bipy complex is formed in the lower buffer region and then the addition ofHis takes place resulting in 111 ternary complex formation. The formation constants (K MAL ) of the resulting mixed ligand complexes have been calculated at 30±1°C (=0.1 KNO3) and the values have been found to be higher than the formation constants of 12 and lower than those of 11 metal—His complexes. The order of stability in terms of metal ions follows the order, Ni(II)>Zn(II)>Cd(II).With 2 Figures  相似文献   

12.
Summary The separation of some purines by thin-layer chromatography, utilizing precoated plates with Silicagel R as stationary phase and the following mobile phases: i-butanol: methylethylketone: ammonium hydroxide 25%: water (40252015) and n-propanol: ammonium hydroxide 25%: water (80155) is reported.Visualisation of the spots has been achieved by spraying with aqueous 1% uranyl acetate and irradiating with UV both at 254 and 366 nm. The visual detection of a spot was 0.01 g.  相似文献   

13.
A series of mixed oxides and ferrites of iron and cobalt has been prepared by taking iron and cobalt in the atomic ratio 10.50, 11.33 and 13.00, respectively. These samples were prepared by calcination of the stoichiometric amount of their respective nitrate salts for 6 h in air at 500±10°C. Characterization of the samples has been carried out using Mössbauer spectroscopy. Percentage formation of -Fe2O3 and CoFe2O4 has been determined using the same technique. These results have been supplemented by X-ray diffraction studies. The particle size has been calculated using Scanning Electron Microscopy. the decomposition of 0.5% w/v hydrogen peroxide at 40°C over the catalyst has also been studied.  相似文献   

14.
Zusammenfassung Die Extraktion des Kupfers als Polyäthylenglykol-saccharinatocuprat(I) ermöglicht die Abtrennung von Kupfermengen ab 10 g aufwärts von Metallen bei den Verhältnissen CuBi PbZnCdCoFeAl bis 15000 2000015000100000400000150000 106. Die auftretenden Fehler liegen allgemein unterhalb von 2%. Das extrahierte Kupfer wird entweder als Carbonatokomplex [Cu(CO3)2]2– oder mit Rubeanwasserstoff photometrisch bestimmt. Niedrige Kupfergehalte in Stählen sind mit genügender Genauigkeit bestimmbar.Dem Fonds der chemischen Industrie danken wir für Unterstützung der Arbeit.  相似文献   

15.
Zusammenfassung Thiocaprolactam (T) eignet sich zur Goldbestimmung im Konzentrationsbereich 10 bis 130 g Au/ml mit einem Fehler von ±0,5g. Thiocaprolactam bildet mit [AuCl4] eine Verbindung im molaren Verhältnis TAuCl=112, mit [AuJ4] im molaren Verhältnis TAuJ=213. Dagegen bilden sich im System T:Au:Br zwei verschiedene Verbindungen: Ein Bromidkomplex mit höherem Goldgehalt TAu=12, der mit Chloroform extrahierbar ist, und eine sich als Niederschlag ausscheidende Verbindung mit dem Verhältnis TAuBr=112.
Thiolactams as reagents in quantitative analysis. IX
Summary Thiocaprolactam (T) is suitable for the determination of gold in the concentration range 10–130g Au/ml with an error of ±0.5g. Thiocaprolactam yields with [AuCl4] a compound in the molar ratio TAuCl=112, with [Aul4] in the molar ratio TAuI=213. On the other hand various compounds result in the system TAu Br. The molar ratio in the case of the bromide complex has a higher gold content, namely TAu=12; this product is extractable with chloroform and a compound that comes down as a precipitate shows the ratioT Au Br=112.


Herrn Dr.K. Czerepko möchte ich hiermit meinen Dank für die Diskussion der Ergebnisse aussprechen.  相似文献   

16.
Summary Interactions of tetrakis--acetato-dirhodium(II) with purine-derived ligands of biological interest such as the cytokinins 6-furfurilaminopurine (K), 6-benzylaminopurine (BAP), 6-furfurilaminopurine riboside (KR) and 6-benzylaminopurine riboside (BAPR) have been studied by means of magnetic susceptibility measurements at room temperature, i.r. and electronic spectroscopy and thermogravimetric analysis 11 metal:ligand adducts were obtained with all ligands; in addition 12 adducts were obtained with KR and BAPR. The most plausible structure for the 11 adducts is a polymeric bridging one, involving both axial positions of the RhII dimer and two N-sites of the purine moiety; for the 12 adducts only one N-site is involved.  相似文献   

17.
The formation of mixed ligand complexes of Cu(II) with 1,10-phenanthroline or 2,2-bipyridyl in presence of an -amino acid (glycine, alanine, phenylalanine or norleucine) have been studied by the pH-metric method. The pH-titrations of the reaction mixtures in equimolar concentrations have shown the simultaneous addition of the ligands resulting 111 ternary complex formation. The equilibrium and formation constants of the resulting ternary complexes have been calculated (30±1 °C; =0.1 KNO3). The order of stability in terms of the secondary ligands has been found to be:Phe > Ala > Gly > Norleu.
Komplexe mit gemischten Liganden von biologischer Bedeutung [Cu(II)—1,10-Phenanthrolin oder 2,2-Bipyridyl—-Aminosäuren]
Zusammenfassung Die Bildung gemischter Komplexe von Cu(II) mit 1,10-Phenanthrolin oder 2,2-Bipyridyl in Gegenwart einer -Aminosäure (Glycin, Alanin, Phenylalanin oder Norleucin) wurde pH-metrisch untersucht. Die pH-Titration der Reaktionsmischungen in äquimolaren Konzentrationen zeigten, daß der gleichzeitige Zusatz der Liganden zu ternären 111-Komplexen führt. Die Gleichgewichts- und Bildungskonstanten der resultierenden ternären Komplexe wurden bestimmt (30±1 °C; =0,1 KNO3). Die Reihenfolge der Stabilität bezüglich der sekundären Liganden istPhe > Ala > Gly > Norleu.
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18.
Summary Synthesis of barbituric and thiobarbituric acid complexes derived from cobalt(II), nickel(II) and copper(II) salts were carried out. The elemental analyses suggest a range of stoichiometries, 11, 12 and 13. Electronic spectra and magnetic susceptibility measurements were used to infer the structures. The i.r. spectra of the ligands and their complexes are used to identify the type of bonding.  相似文献   

19.
    
Zusammenfassung 2-Mercaptopyridin-N-oxid bildet mit V(V) in wäßriger Lösung einen nicht in unpolare Lösungsmittel extrahierbaren (11)-Komplex. Mit einem Molekül Alkohol setzt sich dieser jedoch um zu einem roten, in Chloroform extrahierbaren Esterchelat. Bei Reagensüberschuß wird V(V) reduziert, und es bildet sich ein (V(IV)MPyO=12)-Komplex, der gut extrahierbar ist. Mit HCl bildet dieser ein nur teilweise extrahierbares grünes (11)-Säureaddukt. Die Zusammensetzung der Chelate wird anhand der Spektren diskutiert.
On chelates of vanadium with 2-mercaptopyridine-N-oxide
Summary 2-Mercaptopyridine-N-oxide forms a 11 chelate with V(V) in aqueous solution, which cannot be extracted into unpolar solvents. In presence of alcohols, however, it reacts to an extractable red ester chelate with one molecule of alcohol. Excess of reagent reduces V(V) and forms a V(IV)MPyO=12 chelate, which can be well extracted into chloroform. With hydrochloric acid a green only partly extractable 11 adduct is formed. The composition of the chelates is discussed by means of the spectra.
Wir danken dem Minister für Wissenschaft und Forschung des Landes Nordrhein-Westfalen, Landesamt für Forschung, Düsseldorf, der Deutschen Forschungsgemeinschaft, Bonn-Bad Godesberg, sowie dem Verband der Chemischen Industrie, Fonds der Chemie, Frankfurt/Main, für Sachbeihilfen.  相似文献   

20.
    
Zusammenfassung Die Flüssig-flüssig-Extraktion von Gold aus stark salzsaurer Lösung mit Methylenchlorid bei Gegenwart von Polyäthylenglykol-400 ermöglicht die Trennungen AuFe = 15000, AuCo = 15000, AuNi = 13500, AuMn = 110000, AuPd = 13000, AuPt = 1200 und AuRh = 175. Die photometrische Bestimmung erfolgt in der nichtwäßrigen Phase bei 320 nm.  相似文献   

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