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1.
Equilibrium distribution coefficients have been determined for the extraction of cobalt(II) with 8-mercaptoquinoline as a function of pH and reagent concentraton at ambient temperature. The extractable complex is a diadduct, i. e. two molecules of the reagent are coordinated to the cobalt(II) chelate. The adduct formation constant in chloroform and the overall formation constant in the aqueous phase have been determined. Pyridine and its methyl derivatives were found to enhance the extraction of Co(II) into chloroform in the presence of 8-mercaptoquinoline. From the extraction equilibrium data, the adduct formation constants of 12 chelate to nitrogen base adducts were evaluated. The special role of steric factors is discussed.  相似文献   

2.
Equilibrium distribution coefficients have been determined, for the extraction of cobalt(II) with resacetophenone oxime as a function of pH and reagent concentration at ambient temperature. RAPOX forms simple 12 chelate with cobalt(II). Synergistic extraction was observed with pyridine and its methyl derivatives and some organophosphorous compounds. From the extraction equilibrium data, the adduct formation constants of 12 chelate to adducting ligand adducts were evaluated.  相似文献   

3.
The reaction of 1,4-(2-sulpho-4-methylanilino)anthraquinone (quinizarin green,QG) and its non-sulphonated derivative (NSQG) with Ce(III), Th(IV), and U(VI) was investigated. Spectrophotometric and conductometric studies were carried out to investigate the stoichiometry of the complexes formed. The studies revealed the formation of 11 and 12 (ML) complexes. The apparent stability constants of the different complexes were determined. The structure of the ligand in the solid chelates was studied by IR spectrophotometry which showed that the chelate formation takes place through the oxygen of the C=O group and the -imino nitrogen.

Mit 6 Abbildungen  相似文献   

4.
Summary The ionic behaviour of 1-phenyl-3-pyrazolidinone (phenidone) at different pH values and its complexes with a selected group of metal ions such as Mg(II), Al(III), Cr(III), Mn(II), Fe(III), Co(II), Ni(II), Cu(II) and Zn(II) were investigated in the pH range of 1–13 by paper electrophoresis. pH-mobility curves were determined for phenidone, the nine metal ions and 21 metal-ligand systems with 1, 110 and 1100 metal: ligand ratios. The effect of the pH on complex formation and the influence of the phenidone concentration on the metal ion mobilities are discussed.Presented at the XXII International Conference on Coordination Chemistry, August 23–27, 1982, Budapest (Hungary).  相似文献   

5.
The palladium catalyzed telomerization of isoprene with methanol as a nucleophilic agent has been investigated, applying the reaction system Pd-complex, tributylphosphine, sodium methylate, isoprene and methanol in a ratio of 1232002000. Two main products were found: 1-methoxy-3,6-dimethylocta-2,7-diene with a head-head coupling (I) and 1-methoxy-2,6-dimethylocta-2,7-diene with a tail-head-coupling (II). By substituting part of the methanol by different solvents the formation of I and II, respectively, can be controlled to a large extent.  相似文献   

6.
Summary A Sensitive and Highly Selective Extractive Spectrophotometric Method for the Determination of Palladium Palladium forms an anionic chelate with 4-(2-pyridylazo)resorcinol (PAR, H2R) which is extractable with xylometazolonium cation (XMH) into chloroform in the pH range 7.2–7.8 giving an intensely pinkish red coloured solution. The coloured species exhibits maximum absorbance at 520 nm with molar absorptivity 3.34×1041·mole–1·cm–1 and obeys Beer's law in the range 0.8–5.30g/ml of palladium. The composition of the extracting species is found to be 111 for Pd(II)PARXMH. Large concentrations of EDTA and oxalate have no interference in the spectrophotometric determination of palladium by this procedure. Based on this a highly selective and sensitive method for the determination of palladium in the presence of Zn(II), Cd(II), Hg(II), Fe(III), Mn(II), Co(III), Mo(VI), Ru(IV), Sb(III), Al(III) is described. The application of this method for the determination of palladium in synthetic mixtures corresponding to the composition of jewel alloy and stibiopalladinite mineral is also demonstrated.  相似文献   

7.
The interaction of 11 Th(IV)-EDTA,-CDTA or-DTPA chelate with glycollic and malic acids has been investigated potentiometrically and the formation of 111 mixed ligand chelates inferred from the potentiometric curves. The hydrolysis and dimerization constants of the binary chelates and the equilibrium constants of the ternary derivatives have been evaluated at 30±1° and 35±1°C and also the thermodynamic functions, viz. F 0, H and S.With 3 Figures  相似文献   

8.
    
Zusammenfassung Mit Hilfe einer Kombination aus drei dünnschichtchromatographischen Anordnungen wurden Trennungen von Hydroxydicarbonsäuren, von Diund Tricarbonsäuren des Citratcyclus und einigen anderen Dicarbonsäuren pflanzlichen Ursprungs durchgeführt. Als Schichtmaterial fand Polyamid Woelm DC Verwendung. Mischungen aus Diisopropyläther-Petroläther-Kohlenstofftetrachlorid-Ameisensäure-Wasser (50202081), Acetonitril-Ameisensäure-n-propylester-Essigsäure-n-propylester-Ameisensäure (45451010) und Amylalkohol-Kohlenstofftetrachlorid-Ameisensäure (403015) dienten als Fließmittel. Eine Behandlung mit Jodsäure, durch die einige der untersuchten Säuren zerstört oder in charakteristischer Weise verändert wurden, bot in Verbindung mit der rein chromatographischen Arbeitsweise zusätzliche Differenzierungsmöglichkeiten.
Summary Separations of hydroxydicarboxylic acids, of di- and tricarboxylic acids from the citrate cycle, as well as of several other dicarboxylic acids of plant origin, were carried out by means of a combination of three thin-layer chromatographic systems. Polyamide Woelm DC was used as the film material. Mixtures of diisopropyl ether-petroleum ether-carbontetrachloride-formic acid-water (50202081), acetonitrile-n-propyl formate-n-propyl acetate-formic acid (45451010), and amyl alcohol-carbon tetrachloride-formic acid (453015) were used as eluents. Treatment with iodic acid, which decomposed or altered the characteristics of some of the tested acids, offered additional differentiation possibilities when combined with the purely chromatographic technique.


IV. Mitteilung: Knappe, E., u. I. Rohdewald: diese Z. 210, 183 (1965).  相似文献   

9.
By IR spectroscopy and TPD the effect of vanadium content on the relative proportion of strongly acidic sites of V2O5/Al2O3 catalyst was studied.
- - V2O5/Al2O3.
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10.
A successive extraction of bitumes from black coal was carried out using the following solvents: petroleum ether, petroleumether-benzene (11), benzene, benzene-ethyl ether (11), ethyl ether, ethyl ether ethanole (11), ethanol. These extract organic products as follows: 0.06, 0.16, 0.11, 0.21, 0.07, 0.29 and 0.70% respectively. The obtained by the above mentioned solvents chujniuds were compounds to the thermal and IR-spectral analysis.
Zusammenfassung Mittels folgender Lösungsmittel wurde eine sukzessive Extraktion von Bitumen aus Steinkohle durchgeführt: Petrolether, Petrolether-Benzol (11), Benzol, Benzol-Ethylether (11), Ethylether, Ethylether-Ethanol (11), Ethanol. In dieser Reihenfolge konnten organische Produkte zu 0.06, 0.16, 0.11, 0.21, 0.07, 0.29 bzw. 0.70 % extrahiert werden. Die durch aufgeführte Lösungsmittel erhaltenen Verbindungen wurden einer Thermound einer IR-Analyse unterzogen.
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11.
The formation of molecular complexes between Co(II), Fe(III), and Mn(III) porphyrins and -donors in chloroform solution has been investigated using1H NMR. It was shown that their stability is controlled to a large extent by the dimensions of the -donor; interaction of the porphyrins with phenanthroline and anthracene, which contain a condensed aromatic system, is substantially more effective than interaction with benzene-derivative -donors. In the case of Co(II) and Fe(III) porphyrins the affinity to it-acceptors is much more pronounced than the affinity to -donors, whereas the acetate of Mn(III) hematoporphyrin forms molecular complexes with phenanthroline, anthracene, and trinitrobenzene with similar stability constants.Translated from Izvestiya Akademii Nauk SSSR, Seriya Khimicheskaya, No. 8, pp. 1755–1760, August, 1990.  相似文献   

12.
The physical properties as well as the acidity of an amorphous silica-alumina were modified by steam and thermal treatments and a general correlation (including samples modified by other methods) between hydrocarbon formation and surface acidity was obtained.
, . ( , ) .
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13.
The formation of mixed metal complexes between uranium (VI), as the central metal ion, and aluminium (III), indium (III), copper (II), zinc (II) and cadmium (II), as the additional metal ions, with a hydroxycarboxylic acid chosen between citric, tartaric or malic, has been studied using spectrophotometric methods.The effect of pH has been examined, and the results show that at pH=4 stable complexes are formed for most of the systems. At this pH the method of mole ratio and Job's method of continuous variations, were employed to determine the stoichiometry of the mixed metal complexes. Al(III), In(III) and Cu(II) showed a high tendency to form mixed metal complexes with U(VI), while the formation of complexes is uncertain for Cd(II) and Zn(II). The ratio of the ligand to the total metal ion has been found to be 21 and metal:metal ratios of 11 and 12 have been observed.Represents part of the Ph.D. thesis submitted by Emanuel Manzurola to Ben Gurion University of the Negev.  相似文献   

14.
A kinetic study has shown that, in the range of low conversions, the reaction rate depends only on the partial pressure of oxygen. Comparison of the oxidation of acrolein and I-deuteroacrolein suggests that the splitting of the H–CO bond is not rate-limiting.
, , , . 1- , H–CO .
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15.
The effect of reduction of pressure on the shapes of the TG, DTG and DTA curves and the mass-spectra of hydroxide and carbonate phases was investigated in some typical Hungarian red muds. The pressure change caused different decomposition rates of the phases and resulted in better separation of the overlapping thermal curves; this led to advantages as regards phase analysis. For phase analysis the red muds were extracted with water, and the extracts and solid residues were identified by IR- and X-ray methods.
Zusammenfassung Die Wirkung der Druckänderung auf die Form der TG-, DTG- und DTA-Kurven, sowie der MS-Spektra der Hydroxid- und Carbonatphasen in einigen typischen ungarischen Rotschlamm-Sorten wurde geprüft. Die Druckänderung verursachte verschiedene Zersetzungsgeschwindigkeiten der Phasen, führte zur besseren Auftrennung der sich überlappenden thermischen Kurven, und war ausserdem auch hinsichtlich der Phasenanalyse vom Vorteil. Zur Phasenanalyse wurden die Rotschlämme mit Wasser extrahiert und die Extrakte und festen Rückstände mittels IR- und Röntgenmethoden identifiziert.

Résumé On a étudié dans quelques espèces typiques de boues rouges de Hongrie l'effet des variations de pression sur la forme des courbes TG, TGD et ATD ainsi que les spectres de masse des phases hydroxyde et carbonate. La variation de la pression entraîne des vitesses de décomposition différentes. Il en résulte une meilleure séparation des phénomènes dans le cas où ceux-ci se chevauchent ainsi que des avantages du point de vue de l'analyse des phases. L'analyse des phases présentes dans les boues rouges a été effectuée par extraction à l'eau. Les extraits et les résidus solides ont été identifiés par spectrométrie infrarouge et par diffraction des rayons X.

, - . , , . .


Paper presented at the Scientific Session on Thermal Analysis held at Balatonfüred, Hungary, on 14–16 October 1976.  相似文献   

16.
Summary Reactions of 4, 6-diamine-1, 2-dihydro-2-thiopyrimidine (HDATP) with cobalt(II), nickel(II) and copper(II) ions in 12 metal:ligand ratio in aqueous media at 25°C and 0.1 M ionic strength (KNO3), lead to the formation of both [M(DATP)]+ and [M(DATP)2] species, whose stability constants were obtained.On the other hand, in aqueous or ethanolic media, solid complexes with 11, 12, or 13 stoichiometries were isolated. These have been characterized by analytical, i.r. and electronic spectral and magnetic measurement studies, and tentative structures are proposed.  相似文献   

17.
Extraction of U/VI/ by mixtures of 8-hydroxy quinoline /Oxine/ and neutral donors was studied from 0.1M NaCl at a pH 4.5. The presence of a neutral donor enhanced the extraction of U/VI/ and the species responsible for synergism was established to be 11 adduct UO2Ox2S. From the data, the equilibrium constants for the adduct formation reaction were calculated and was found to be the lowest with TBP and the highest with TOPO.  相似文献   

18.
The absorption spectra of 5-fluoro-8-mercaptoquinoline in aqueous solutions at various pH values have been studied. The max values of the 5-fluoro-8-mercaptoquinolinium ion and also of the 5-fluoro-8-mercaptoquinolate ion, and the apparent molar absorption coefficient of the hydrated form have been determined. In the hydrated form, a molecule of water is connected by hydrogen bonds both with the nitrogen and with the mercapto group. The presence of the fluorine atom in positions 5 of the molecule of the 8-mercaptoquinoline increases the acidic properties of the mercapto group and decreases the basic properties of the nitrogen, in comparison with those in 8-mercaptoquinoline. The dissociation constants of 5-fluoro-8-mercaptoquinoline are pKSH=7.49 ± 0.02 (thermodynamic) and pKNH= 1.97 ±0.02 (concentration). The isoelectric point is at pH 4.70.For part XXXVIII, see [4].  相似文献   

19.
Zusammenfassung Die Komplexe des Ni2+ mit o-Methylbenzamidoxim wurden in neutraler und in alkalischer Lösung spektrophotometrisch untersucht. Die Bildungskonstanten sindK 1=40 für 11 undK 2=1,7·102 für 12 in neutraler Lösung und 1 = =(3,92 ±0,2) · 104für 11 und lgK = lg 1 + lg 2 = 3,45 ± ±0,15 für 12 bei 25° und =1 in alkalischer Lösung.
Complex formation in the systemeNi 2+—o-methylbenzamide oxime
The complexes of Ni2+ with o-methylbenzamide oxime were investigated spectrophotometrically in neutral as well as in alkaline solution. The formation constants areK 1=40 for 11 andK 2=1.7·102 for 12 in the neutral solution and 1 = =(3.92 ±0.2) · 104 for 11 and lgK = lg 1 + lg 2 = 3.45 ± ±0.15 for 12 at 25° and =1 for the alkaline solution. *** DIRECT SUPPORT *** A3615139 00007
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20.
Potentiometric studies of the mixed ligand derivatives of 11-Th(IV)—DTPA chelate (whereDTPA=diethylene-triamine pentaacetic acid) with certain secondary ligands, such as lactic, mandelic and o-hydroxynaphthoic acids have been carried out. The pH-titrations of the reaction mixtures containing 111 molar ratio of metal ion toDTPA to secondary ligand have shown the formation of 111 ternary complexes at higher pH (8). The equilibrium constants of the resulting mixed complexes have been determined at 30±1°C and =0.1 (KNO3) and the order of stability in terms of secondary ligands has been found to be o-hydroxy naphthoic acids>mandelic acid>lactic acid.

Mit 1 Abbildung  相似文献   

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