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  • 2005-2009
  • 1980-1984  (4)
  • 1925-1929
  • 1910-1914
  • 1981  (3)
  • 1980  (1)
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  • 2005-2009
  • 1980-1984  (4)
  • 1925-1929
  • 1910-1914
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  • 1
    Electronic Resource
    Electronic Resource
    Fluorine geochemistry of basaltic rocks from continental and oceanic regions and petrogenetic application (1981)
    Springer
    Contributions to mineralogy and petrology 76 (1981), S. 53-59 
    Details
    ISSN: 1432-0967
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences
    Notes: Abstract Fluorine contents in about 300 samples of various types of basalts and related rocks from continental (southwestern U.S.A.; Zaire; Deccan and South Africa) and oceanic regions (Hawaii and Mid-Atlantic Ridge between 23° N and 40° N) were determined by a selective ion-electrode method. Of all of the major components in these basaltic rocks, F shows good correlation only with K2O. It increases regularly from tholeiite to perpotassic basalt on continents, and from tholeiite to nephelinite on Hawaii. In the F-K2O diagram all the basaltic rocks from continents and Hawaii plot between the origin of the coordinate axes and the field of phlogopite in peridotite xenoliths in South African kimberlites. Accordingly, the major proportions of F, K2O and also H2O in these basaltic magmas are derived from phlogopite at the source regions in the upper mantle. On the other hand, F in abyssal tholeiites is relatively higher than that of the other tholeiites at equal K2O content, and it is suggested that most of F, K2O and H2O are derived from pargasites. When it is assumed that the upper mantle phlogopite contains about 10% K2O, 0.4% (0.3–0.5%) F and 4% H2O, H2O content in basaltic magmas from continental including island arc and oceanic island regions can be qualitatively estimated based on their proportions of K2O∶F∶H2O. Similarly, H2O content in abyssal basaltic rocks is also estimated on the basis of F∶H2O in pargasites (Table 2). A suite of Deccan tholeiites shows remarkable F enrichment with increasing K2O due to separation of anhydrous and K-free minerals during fractionation. F in tholeiitic and alkali basalt magmas in Hawaii also increases regularly with K2O during progressive fractionation until the later stages, where rhyodacite and trachyte exhibit a relative decrease owing to the effective subtraction of F-bearing amphibole and apatite in addition to anhydrous minerals.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00373683
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    Paper (German National Licenses)
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  • 2
    Electronic Resource
    Electronic Resource
    Urocanic acid contents in histidinaemic infant and developing rat epidermis (1981)
    Springer
    Journal of inherited metabolic disease 4 (1981), S. 55-56 
    Details
    ISSN: 1573-2665
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract The ratio of urocanic acid to histidine in stratum corneum can be used to differentiate patients with histidinaemia from normal subjects. The histidinaemia heterozygotes have intermediate ratios.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02263588
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    Paper (German National Licenses)
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  • 3
    Electronic Resource
    Electronic Resource
    Dielectric relaxations of Cu(II) salts of ethylene—acrylic acid and styrene—methacrylic acid copolymers (1980)
    Springer
    Colloid & polymer science 258 (1980), S. 61-69 
    Details
    ISSN: 1435-1536
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Zusammenfassung Dielektrische Konstante, ɛ', und Verlust, ɛe", von verschiedenen Cu(II) Salzen von Athylen-Acrylsäure (E-AA) und Styrol-Methacrylsäure (S-MAA) Mischpolymere wurden im Frequenzbereich von 30 Hz bis 30 kHz gemessen. In den Cu(II) Salzen von E-AA, die die dimere Struktur besitzen und als Monohydrate vorliegen, wurden die zwei Relaxationsprozesse, d. h. β′- undy-Prozeβ beobachtet, die durch die Mikro-Brownschen Molekülbewegungen im höheren Temperaturbereich vonT g und durch lokaler Molekülbewegungen im tieferen Temperaturbereich vonT g , verursacht werden. Bei höheren Graden der Neutralisation (20%) wurde die Existenz von Ion-Aggregaten bestätigt. In den Cu(II) Salzen von S-MAA befanden sich drei Typen von KupferKomplexsalzen: monomerer Typ, Kupferacetat Typ und pseudo-Kupferformiat Typ, deren Mischungsverhältnis vom Prozeβ der Verfertigung der Cu(II) Salze abhängig ist. Das dielektrische Verhalten desy-Prozesses ist sehr empfindlich auf die Struktur der Cu(II) Salze.
    Notes: Summary Dielectric constant, ɛ′, and the loss, ɛt", of various Cu(II) salts of ethylene-acrylic acid, E-AA, (9.3 mol% AA) and styrene-methacrylic acid, S-MAA, (4.4 mol% MAA) have been measured in the frequency range of 30 Hz to 30 kHz. In the Cu(II) salts of E-AA which form almost dimeric structure of monohydrated copper acetate, two relaxations were observed, β'-relaxation due to a micro-Brownian molecular motion aboveT g andy-relaxation due to a local molecular motion belowT g . By examining molecular motion and estimating number of polar group for the two relaxations, an existence of ion aggregation was comfirmed at the high degrees of neutralization above 20%. In the Cu(II) salts of S-MAA, there were three types of structure of copper complex, monomeric type, monohydrated copper acetate type and pseudo anhydrous copper formate type, the mixing ratio of which depends on preparation procedure of Cu(II) salts. Dielectric behavior of y-relaxation was sensitively influenced by the structure of Cu(II) salt.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01474955
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  • 4
    Electronic Resource
    Electronic Resource
    Structure and molecular motion of ethylene-acrylic acid copolymers neutralized with manganese (II) and nickel (II) acetates (1981)
    Springer
    Colloid & polymer science 259 (1981), S. 514-521 
    Details
    ISSN: 1435-1536
    Keywords: Mn(II) and Ni(II) salts of E-AA ; Ion-Clusters ; Dielectric Relaxation ; ESR ; SAXS
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Description / Table of Contents: Zusammenfassung Die Existenz von Ionen-Aggregaten in Äthylen-Acrylsäure-Mischpolymerisaten, die durch Mangan-acetat und Nickel-acetat neutralisiert wurden, wurden durch dielektrische Messungen im Temperaturbereich von -180 bis 80 °C und für einige Frequenzen zwischen 30 Hz und 100 kHz, studiert. Dieβ′- undγ-Relaxationsprozesse wurden beobachtet, die durch die Mikro-Brownschen Molekülbewegungen im höheren Temperaturbereich vonT g und durch lokale Molekülbewegungen im tieferen Temperaturbereich vonT g verursacht werden. Die Veränderung in Intensität und Relaxationstemperatur für die beiden Relaxationsprozesse mit dem Grad der Neutralisation deutet auf die Bildung von Ionen-Aggregaten in Bereichen höherer Neutralisation als einem Wert zwischen 3.3 und 14% für das Mn(II)-Salz und als 14% für das Ni(II)-Salz an. Diese Bildung von Ionen-Aggregaten wurde ebenso durch Elektronenspinresonanz (ESR) und durch Kleinwinkel-Röntgenstreuung (KWRS) nachgewiesen. Die ESR-Spektren in den Mn(II)-Salzen zeigen sechs Absorptionen bei 14% Neutralisation und eine Absorption bei 62%. Die KWRS deutet auf die Existenz von Ionen-Aggregaten hin, deren Durchmesser ungefähr 27 Å für das Mn(II)-Salz und 19–23 Å für das Ni(II)-Salz bei höherer Neutralisation als 14% ist.
    Notes: Summary The existence of ion-clusters in ethylene-acrylic acid copolymers (mole% of acrylic acid is 9.3) neutralized with manganese(II) and nickel(II) acetates, respectively, was studied by dielectric measurements in the temperature range of −180 to 80 °C at several frequencies between 30 Hz and 100 kHz. Theβ′ relaxation due to a micro-Brownian molecular motion aboveT g and theγ relaxation due to a local molecular motion belowT g were observed. Variation in the magnitude and the relaxation temperature of the two relaxations with degree of neutralization by manganese/nickel acetate suggest the formation of ion-clusters in the higher degrees of neutralization above a value between 3.3 and 14% for the Mn(II) salts and above about 14% for the Ni(II) salts. Furthermore, this formation of ion-clusters was evidenced by electron spin resonance and small angle X-ray scattering studies. The ESR spectra for the Mn(II) salts exhibited six peaks at 14% of degree of neutralization and one peak at 62%. This indicates the existence of ion-clusters at 62%. The small angle X-ray scatterings suggested the existence of ion-clusters of diameter of about 27 Å for the Mn(II) salts and 19–23 A for the Ni(II) salts, at the high degrees of neutralization above 14%.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01397889
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    Paper (German National Licenses)
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