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Spectrophotometric Investigation of the Complexation of Iron(III)with Ethylene Diamine Tetraacetic Acid and Some Thioligands . In the system FeIII/EDTE/R? SH (Thiophenol, Toluen-3,4-dithiol, Thioethanol bzw. Thioglycollic acid) ternary complexes could be detected in solution. By means of spectrophotometric measurements the ratio of components in the species Fe:L:L′=1:1:1 was determined. The optical properties of the complexes are discussed. 相似文献
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Jerzy Minczewski und Cezary Rózycki 《Fresenius' Journal of Analytical Chemistry》1968,239(3):158-163
Zusammenfassung Eine Methode zur Zinkbestimmung in Eisen(III)-oxid wird vorgeschlagen. Sie beruht auf der Extraktion des Zinkthiocyanatkomplexes aus schwach saurer Lösung mit Isoamylalkohol. Eisen wird mit Ammoniumfluorid, Kupfer mit Natriumthiosulfat maskiert. Kobalt und Nickel stören nicht, wenn der Extrakt mit einer Waschlösung, die Nitroso-R-Salz enthält, gewaschen wird. Zink wird mit einer Pufferlösung (pH 9) re-extrahiert und mit Dithizon colorimetrisch bestimmt. Bei der Extraktion wird Zink gleichzeitig von gröeren Mengen Cd, Pb und Bi, die die colorimetrische Bestimmung in ammoniakalischer Lösung stören, abgetrennt.
Thiocyanate extraction and dithizone determination of zinc in iron(III) oxide
A Separation of microgram amounts of zinc from large amounts of iron (100 mg) and from 100 g of Co, Cd, Ni, Cu and 200 g of Bi, Pb has been worked out. Zinc is extracted by isoamyl alcohol from a solution containing ammonium thiocyanate, ammonium fluoride (for masking iron) and sodium thiosulphate (for masking copper). Cobalt and nickel are removed from the extract by shaking with a washing solution containing nitroso-R-salt. Zinc is in this way also separated from Cd, Pb and Bi interfering with the colorimetric determination with dithizone. The method was applied to the determination of zinc in ferric oxide.相似文献
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Synthesis and Reactivity of Dimethylaminoalkylideneaminooxiarsines The reactions of As[N(CH3)2]3 with oximes result in the formation of the oximates [(CH3)2N]2AsONCRR′, (CH3)2N As(ONCRR′)2 and As(ONCRR′)3. The eleavage of the As-N-bond with alcohols, thiols and diols are described. The reactions of CH3As[N(CH3)2]ONCRR′ with water, amine and alcohols are examined. IR-and 1H-NMR-spectral data are presented. 相似文献
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On the Solubility of LaCl3 in Hydrochlorid Acid. Comparative Study of the Saturated Metal Chloride ? HCl? H2O Systems The results of solubility investigations in the LaCl3? HCl? H2O system at 15, 25 and 35°C were presented. On the basis of the experimental data, of references and of a model of the authors conclusions were drawn on the structure of the saturated and almost saturated solutions. 相似文献
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Zusammenfassung Der thermische Zersetzungsprozeß von Eisen(III)akrylat und Eisen(II)polyakrylat wurde mittels analytischer, magnetischer und Röntgenverfahren untersucht. Erfolgt die Zersetzung ohne Luft, so treten ferromagnetische Eigenschaften bei Eisen(III)akrylat bei 224° auf, während bei Zersetzungsprodukten des Eisen(III)-polyakrylats Spuren der ferromagnetischen Phase nur bei Temperaturen >240° nachgewiesen werden können. Ein plötzlicher Anstieg der Magnetisierung tritt im Falle von Eisen(III)akrylat im Temperaturbereich von 300 bis 350° und beim Eisen(III)-polyakrylat zwischen 300 und 440° auf. Aufgrund der Röntgenuntersuchung ist Magnetit für die ferromagnetischen Eigenschaften verantwortlich. Bei Temperaturen über 500° ist Magnetit mit -Fe kontaminiert. Dieselbe Verunreinigung tritt auch bei Eisen(III)-polyakrylatprodukten auf, doch ist hierfür eine Zersetzungstemperatur >600° erforderlich.
The processes of thermal decomposition of iron(III) acrylate and iron(III) polyacrylate have been studied by analytical, magnetic and X-ray methods. For thermal decomposition in the absence of air, ferromagnetic properties are observed at 224° in the case of iron(III) acrylate, whereas in the decomposition products of iron(III) polyacrylate traces of a ferromagnetic phase can be detected only at temperatures >240°. An abrupt rise of magnetization occurs at 300–340° for iron(III) acrylate and at 300–440° for iron(III) polyacrylate. According to X-ray investigations the phase responsible for the ferromagnetic properties is magnetite. At >500° the magnetite is contaminated with -Fe. The same contamination occurs in the iron(III) polyacrylate products, but the decomposition temperature required must be >600°.
Résumé On a étudié la décomposition thermique de l'acrylate de fer(III) et du polyacrylate de fer(III) par des méthodes analytiques, par mesures magnétiques et par diffraction des rayons X. En l'absence d'air, on observe des propriétés ferromagnétiques à 224° dans le cas de l'acrylate de fer(III) tandis que des traces de la phase ferromagnétique ne peuvent être observées qu'au-dessus de 240° dans le cas du polyacrylate de fer(III). Une brusque augmentation de la magnétisation se produit entre 300 et 340° avec l'acrylate de fer(III) et entre 300 et 440° avec le polyacrylate de fer(III). L'examen aux rayons X montre que la phase responsable des propriétés ferromagnétiques est la magnétite. Aux températures supérieures à 500°, la magnétite est contaminée par le fer-. La présence de fer- est également observée dans le cas du polyacrylate de fer(III) mais la température de décomposition nécessaire est alors supérieure à 600°.
, - (III). , , 224°, , 240°. 300–340° 300–440°, , - . , , , . 500° -Fe. , , > 600°.相似文献
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By several methods of measurements (saturation magnetization, paramagnetic susceptibility, specific surface, specific catalytic activity, Debye-Scherrer-diagrams) the formation of molar nickel ferrite, NiFe2O4, by the reaction NiO + Fe2O3 = NiFe2O4 was studied. Comparing these methods some problems of the process of ferrite formation, f. i. the relation between the energy quantity needed for ferrite formation and the output of the endproduct, should be explained. Both, kinetic and thermodynamical calculations were made and their results are discussed in connection with the literature. 相似文献
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Synthesis, Structure, and Reactivity of Bis(dialkylamino)diphosphines Starting with the aminochlorophosphines iPr2N? PCl2 1 and (iPr2N)2P? Cl 2 , the synthesis of some new functionalized aminophosphines (iPr2N)2P? SiMe3 3a , (iPr2N)2P? SnMe3 3b , (iPr2N)(DMP)P? Cl 4 , iPr2N? P(SiMe3)2 5 and iPr2N? P(SiMe3)Cl 6 is reported. Reactions of 2 with different phosphides yield the aminodiphosphines (iPr2N)2P? P(SiMe3)2 7a , (iPr2N)2P? P(SiMe2tBu)2 7b , (iPr2N)2P? PPh2 8 and (iPr2N)2P? PH2 9 . The phosphines 3a/b react with halogenophosphines to the aminohalogenodiphosphines (iPr2N)2P? PCl2 10 , (iPr2N)2P? PtBuCl 11 and (iPr2N)2P? P(NiPr2)Cl 12 . The ambivalente aminophosphine 6 gives the aminotrichlorodiphosphine Cl(iPr2N)P? PCl2 13 after condensation with PCl3, while the reactions with the corresponding lithiumphosphides yield the aminosilyldiphosphines (iPr2N)(SiMe3)P? P(SiMe3)2 14a and (iPr2N)(SiMe3)P? P(SiMe2tBu)2 14b . The aminochlorophosphines 2/4 are reductively coupled with magnesium leading to the symmetrically substituted tetraaminodiphosphines (iPr2N)2P? P(iPr2N)2 15a and DMP(iPr2N)P? P(iPr2N)DMP 15b . The functionalized aminosilyldiphosphine 7a is treated with methanol to yield the diphosphine (iPr2N)2P? PH(SiMe3) 16 and gives the lithium phosphinophosphide (iPr2N)2P? PLi(SiMe3) 17 after metallation with n-BuLi. The compounds are characterized by their NMR and mass spectra and the 31P-NMR values of the diphosphines are discussed according to their substituents. The crystal structures of 7b, 8 and 15b showing significantly differing conformations are presented. 相似文献
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Josef Stadlwieser Frank Kienzle Wolf Arnold Klaus Gubernator Peter Schnholzer 《Helvetica chimica acta》1993,76(1):178-186
Stability and Reactivity of 3-Cyclopropylideneprop-1-enyl Ethyl Ether 3-Cyclopropylideneprop-1-enyl ethyl ether ( 1 ) dimerizes to a cyclobutane derivative 2 which, upon prolonged heating, is converted to a cyclooctadiene ( 3 ). The reactivity of 1 is discussed. The structures of 2 and 3 as well as of their derivatives have been determined using 1H-NMR spectroscopy and X-ray crystal-structure analysis. 相似文献
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