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  • 1
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    Analytical chemistry 48 (1976), S. 541-542 
    ISSN: 1520-6882
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    Journal of Inorganic and Nuclear Chemistry 41 (1979), S. 251-252 
    ISSN: 0022-1902
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Chemistry and Pharmacology , Energy, Environment Protection, Nuclear Power Engineering
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Amsterdam : Elsevier
    Talanta 24 (1977), S. 122-123 
    ISSN: 0039-9140
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 4
    ISSN: 1436-5073
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Bis zu 10−5 M Konzentration wurde Thorium durch visuelle Titration mit N-(2-Hydroxyethyl)ethylendiaminotriessigsäure bei etwa pH 2,0 mit SPADNS als Indikator bestimmt. Der Farbwechsel erfolgt von Violett nach Scharlachrot. Das optimale Gebiet für die Bestimmung liegt bei 0,05-75μg/25ml. Die relative Standardabweichung bei 50μg/25ml beträgt 0,9% und 0,3% für 1 mg/25 ml. Die Toleranzgrenzen für verschiedene Fremdionen wurden ermittelt. Das Verfahren wird zur Thoriumbestimmung in Monazitsand verwendet.
    Notes: Summary Thorium at concentrations down to 10−5 M is determined byvisual titration withN-(2-hydroxyethyl)ethylenediaminetriacetic acid at about pH 2.0 with SPADNS as indicator. The colour change is from violet to scarlet. The optimum range for the determination is 0.05–75 mg/25 ml. The relative standard deviation at the 50μg/ 25 ml level is 0.9%, and 0.3% for 1 mg/25 ml. The tolerance limits for various foreign ions have been established. The method finds use in the determination of thorium in monazite sand.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Journal of thermal analysis and calorimetry 15 (1979), S. 3-10 
    ISSN: 1572-8943
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Résumé L'acide all-cis-l,2,3,4-cyclopentanetétracarboxylique forme des complexes 1∶1 avec les métaux tels que Al(III), Y(III) et Ga(III) et a été isolé à l'état solide à partir des solutions aqueuses. La thermogravimétrie de ces complexes vient à l'appui des formules probables établies par l'analyse élémentaire. La cinétique de la décomposition thermique de plusieurs d'entre eux a été étudiée. Divers paramètres cinétiques comme l'énergie d'activation, l'ordre de la décomposition, le facteur de fréquence et l'entropie d'activation ont été évalués. La comparaison des deux premières constantes obtenues par deux méthodes différentes montre une très bonne concordance des valeurs.
    Abstract: Zusammenfassung All-cis-l,2,3,4-Cyclopentantetracarbonsäure bildet 1∶1 Komplexe mit Metallen wie Al(III), Y(III) und Ga(III). Sie wurden in festem Zustand aus den wässerigen Lösungen isoliert. Die Thermogravimetrie dieser Komplexe unterstützt die wahrscheinlichen Formeln, welche den Verbindungen auf Grund der Elementaranalyse Zugeschrieben worden sind. Die Kinetik einiger dieser thermischen Zersetzungen wurde untersucht. Verschiedene kinetische Parameter, wie die scheinbare Aktivierungsenergie, die Ordnung der Zersetzung, der Frequenzfaktor und die Aktivierungsentropie wurden bewertet und die ersten beiden Konstanten mittels zweier Methoden verglichen und in guter Übereinstimmung mit einander gefunden.
    Notes: Abstract All-cis-1, 2, 3, 4-cyclopentane tetracarboxylic acid forms 1∶1 complexes with metals like Al(III), Y(III) and Ga(III), and have been isolated in solid state from the aqueous solutions. Thermogravimetry of these complexes supports the probable formulae assigned on the basis of elemental analysis. Kinetics of some of the thermal decompositions have been studied. Various kinetic parameters such as apparent activation energy, order of decomposition, frequency factor and activation entropy have been evaluated and the former two constants have been compared by two methods and are in reasonable agreement with each other.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Reaction kinetics and catalysis letters 19 (1982), S. 193-196 
    ISSN: 1588-2837
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Abstract Описывается осциллирующее поведение окислительно восстановительного потенциала в закрытой системе с медленным перемешиванием салициловой и 5-сульфосалициловой кислоты с кислым (H2SO4) броматом в присутствии и отсутствии катализатора. Оптимальные и граничные условия для каждой системы, обладающей временной осцилляцией, были определены и сравнены. 5-Сульфосалициловая кислота обладает лучшей осцилляцией как в катализированных (Ферроин), так и в некатализированных условиях, чем салициловая кислота. Ферроин оказался в обеих системах лучшим катализатором, нежели Ce(IV) и Mn(II). Рассматривалась роль сульфоновой группы (−SO3H), в осшиллирующем поведении.
    Notes: Abstract Oscillatory behavior in the redox potential in a slowly stirred closed system of salicylic and 5-sulfosalicylic acid with acidic (H2SO4) bromate is reported in the presence and absence of a catalyst. Optimum and boundary conditions for each system exhibiting temporal oscillations were established and compared. 5-sulfosalicylic acid exhibits a better oscillatory behavior both in catalyzed (Ferroin) and uncatalyzed conditions than salicylic acid. Ferroin proved to be a better catalyst in both systems as compared to Ce(IV) and Mn(II), etc. The role of the sulfonic (−SO3H) group for this oscillatory behavior has been envisaged.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Reaction kinetics and catalysis letters 16 (1981), S. 399-402 
    ISSN: 1588-2837
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Abstract Сообщается химическая осцилляция в некатализированном окислении гидрохинона и нитрофенолов броматом. Реакция сильно ингибируется перемешиванием. Описывается эффект одноэлектронных окислительно-восстановительных пар (катализаторы EZ) на систему.
    Notes: Abstract Chemical oscillatory behavior in the uncatalyzed bromate oxidation of hydroquinone and nitrophenols is reported. The reaction is strongly inhibited by stirring. Effect of one-electron redox couples (EZ catalysts) on the system is described.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Springer
    Reaction kinetics and catalysis letters 18 (1981), S. 509-509 
    ISSN: 1588-2837
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Reaction kinetics and catalysis letters 24 (1984), S. 235-237 
    ISSN: 1588-2837
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Abstract Присутствие органического редокс-индикатора, натриевой соли 4-дифениламин-4-сульфоновой кислоты, вместо неорганических катализаторов, значительно усиливает осциллирующее поведение 5-сульфосалициловой кислоты в кислотном бромате, оптимальнос при медленном перемешивании (≈50 об./мин).
    Notes: Abstract The presence of an organic redox indicator, sodium 4-diphenylamine-4-sulfonate, instead of inorganic catalysts has been found to greatly enhance the oscillatory behavior of 5-sulfosalicylic acid in acidic bromate under optinum conditions and slow stirring (≈50 rpm).
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    Springer
    Reaction kinetics and catalysis letters 25 (1984), S. 87-91 
    ISSN: 1588-2837
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Abstract Были определены и сравнивались оптимальные и граничные условия для катализированных и некатализированных временных осц илляций в редокс-потенциалах окисления моно-и дигидроксибензойных кислот в кислом бромате (H2SO4). Количество и относительное положение ги дроксильных групп в ароматическом кольце влияют на осциллирующее поведение. Ферроин, по сравнению с Ce(IV) и Mn(II), значительно усиливает осциллирую щее поведение. Предлагается возможное обьяснение осциллир ющего поведения зтой системы.
    Notes: Abstract Optimum and boundary conditions for uncatalyzed and catalyzed temporal oscillations in the redox potentials in the oxidation of mono- and dihydroxybenzoic acids in acidic bromate (H2SO4) have been established and compared. The number and relative positions of the functional groups, in the aromatic ring have been found to influence the oscillatory behavior. Ferroin has been found to enhance the oscillatory behavior considerably as compared to Ce(IV) and Mn(II). A probable explanation of the oscillatory behaviour of these system is suggested.
    Type of Medium: Electronic Resource
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