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  • 1
    Electronic Resource
    Electronic Resource
    Electrochemistry of solutions in liquid ammonia. Part VII. The use of glass electrodes for ammonium and sodium cations as ion-selective sensors at −40 °C (1983)
    Springer
    Journal of solution chemistry 12 (1983), S. 829-846 
    Details
    ISSN: 1572-8927
    Keywords: Specific ion electrodes ; liquid ammonia ; activity coefficients ; lithium/lanthanum glass electrodes ; pH determination
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The behavior of Li/La glass electrodes as specific ion sensors for NH 4 + and Na+ cations in liquid ammonia solutions at −40°C has been assessed using concentration cells with transference. The measurement of emf's of cells with very high resistances due to glass at −40°C has been overcome partly by the use of thinly blown Li/La glass and mainly through the design and use of a ‘floating shield’ emf measuring system. For solutions of NH4NO3, NH4I, NH4BF4, and NH4Cl almost linear pNH4 vs. emf responses were observed between pNH4 0 and 5; for NH4NO3 solutions the slope (40±1 mV/pNH4) was invariant for substantial increases in Na+ concentrations. Solutions of NaNO3, NaCN, NaClO4, NaNCS, NaN3, and NaNO2 gave almost linear pNa vs. emf responses but the slopes were markedly dependent upon the NH 4 + concentration. Estimates of the mean molal ion activity coefficients for nitrate solutions were obtained from earlier transference data: γ±(NaNO3)=0.14±0.02 and γ±(NH4NO3)=0.30±0.03 at 10− molal concentration in fair agreement with earlier data.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00643923
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  • 2
    Electronic Resource
    Electronic Resource
    Pyrimido[4,5-e](1,2,4)-triazolo[3,4-b](1,3,4)-thiadiazine-7,9(6H8H)-diones (1985)
    Springer
    Monatshefte für Chemie 116 (1985), S. 633-637 
    Details
    ISSN: 1434-4475
    Keywords: Heterocyclic compounds
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Es wurden einige 5H-pyrimido[4,5-e](1,2,4)-triazolo[3,4-b](1,3,4)-thiadiazin-7,9(6H,8H)-dione (4 a–d) mittels Kondensation von 3-Alkyl-4-amino-5-mercapto-(1,2,4)-triazolen (1 a–d) mit 5-Brombarbitursäure (2 a) dargestellt. Des weiteren wurden einige 9a-Nitro-5H-pyrimido[4,5-e](1,2,4)-triazolo[3,4-b](1,3,4)-thiadiazin-7,9(8H,9aH)-dione (5 a–d) über die Kondensation von1 a–d mit 5-Brom-5-nitrobarbitursäure (2 b) und anschließender Cyclisierung mitPPA synthetisiert. Die angeführten Strukturen wurden mittels PMR-Spektren und analytischen Daten abgesichert.
    Notes: Abstract Some 5H-pyrimido[4,5-e](1,2,4)-triazolo[3,4-b](1,3,4)-thiadiazine-7,9-(6H,8H)-diones (4 a–d) have been synthesised by the condensation of 3-alkyl-4-amino-5-mercapto-(1,2,4)-triazoles (1 a–d) with 5-bromobarbituric acid (2a). Similarly some 9a-nitro-5H-pyrimido[4,5-e](1,2,4)-triazolo[3,4-b](1,3,4)-thiadiazine-7,9(8H,9aH)-diones (5 a–d) have been obtained by the condensation of1 a–d with 5-bromo-5-nitrobarbituric acid (2b) and final cyclisation withPPA. The structures have been confirmed by PMR spectra and analytical results.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00798788
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  • 3
    Electronic Resource
    Electronic Resource
    Spectrochemistry of solutions, part 23. Changes of enthalpy and entropy in the formation of contact ion pairs: A vibrational spectroscopic appraisal using thiocyanate and azide solutions (1992)
    Springer
    Monatshefte für Chemie 123 (1992), S. 521-535 
    Details
    ISSN: 1434-4475
    Keywords: Enthalpy ; Entropy ; Vibrational spectra ; Ion pairs ; Electrolyte solutions
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung Um die Enthalpie- und Entropieänderungen bei der Bildung von Kontaktionenpaaren sowohl quantitativ als auch qualitativ zu bestimmen wurden Schwingungspektren von Lösungen von LiNCS, Mg(NCS)2 and LiN3 in flüssigem Ammoniak, Dimethylformamid, Dimethylsulphoxid and Acetonitril untersucht. Im Gegensatz zu Vorhersagen sind die Enthalpie- und Entropie in allen untersuchten Fällen positiv. Diese Tatsache deutet daraufhin, daß die treibende Kraft des Assoziationsprozesses die Umstrukturierung der Lösung und nicht die Wechselwirkungsenergie zwischen Kation und Anion ist. Diese Eigenschaft der Kontaktionenpaarbildung ist wahrscheinlich auf eine große Anzahl von Lösungsmitteln übertragbar. Folgende, spezifische Werte wurden für die thermodynamischen Parameter ermittelt: LiNCS/DMF, ΔG=−1.3 (1)kJmol−1, ΔH ass =+1.8 (5)kJmol−1, ΔS ass =+10 (2)Jmol−1K−1; LiNCS/DMSO, ΔG=+0.9 (2)kJmol−1, ΔH ass =+0.3 (3)kJmol−1; Mg (NCS)2/DMF, ΔG ass =−4.0 (3)kJmol−1, ΔH ass =+15 (4)kJmol−1, ΔS=+64 (17)kJmol−1; LiN3/DMSO, ΔG ass =−2.5 (3)kJmol−1, ΔH ass =+4.9 (9)kJmol−1, ΔS ass =∼+25 (10)JK−1mol−1.
    Notes: Summary The vibrational spectra of solutions have been analyzed to assess both qualitatively and quantitatively the changes in enthalpy and entropy for ion pair formation in solutions of LiNCS, Mg(NCS)2, and LiN3 in liquid ammonia, dimethylformamide, dimethylsulphoxide and acetonitrile. Contrary to predictions both the ΔH ass and ΔS ass terms are all positive in the cases examined, indicating that the driving force in the ion association process derives from solvent-solute restructuring, and not the energy of the interaction between the cation and anion. This characteristic of contact ion pair formation is likely to be found to be applicable over a wide range of solvents. The following specific values of the thermodynamic parameters at 298 K have been obtained: LiNCS/DMF, ΔG=−1.3 (1) kJ mol−1, ΔH ass =+1.8 (5) kJ mol−, ΔS ass =+10 (2) J mol−1 K−1; LiNCS/DMSO, ΔG=+0.9 (2) kJ mol−1, ΔH ass =+0.3 (3) kJ mol−1; Mg(NCS)2/DMF, ΔG ass =−4.0 (3) kJ mol−1, ΔH ass =+15 (4) kJ mol−1, ΔS=+64 (17) kJ mol−1; LiN3/DMSO, ΔG ass =−2.5 (3) kJ mol−1, ΔH ass =+4.9 (9) kJ mol−1, ΔS ass =∼+25 (10) J K−1 mol−1.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00816846
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  • 4
    Electronic Resource
    Electronic Resource
    Changes in composition and enzyme activities of mitochondrial and post-mitochondrial fractions of tissues of rats given mustard oil diet with carnitine and/or fish oil (1981)
    Springer
    European journal of nutrition 20 (1981), S. 188-193 
    Details
    ISSN: 1436-6215
    Keywords: enzyme activity ; mitochondria ; mustard oil ; carnitin ; fish oil
    Source: Springer Online Journal Archives 1860-2000
    Topics: Agriculture, Forestry, Horticulture, Fishery, Domestic Science, Nutrition , Medicine
    Notes: Summary The effects of short-term feeding of a 20 % mustard oil (containing 47 % erucic acid) diet with 0.1 % carnitine and/or fish oil on the activity of enzymes of lipid metabolism in mitochondrial and post-mitochondrial fractions of heart, liver, and skeletal muscles of rats were determined to study the reversal of erucic acidinduced lipidosis. Histopathological changes were also studied. The inclusion of fish oil or fish oil plus carnitine in a mustard oil diet, especially the latter, eliminated the histopathologically detectable lipidosis in heart and skeletal muscles. The reason for this appears to be the increased activity of lipase and phospholipase in tissue homogenates and of cholesterol ester hydrolase in the post-mitochondrial fraction; and also an increase in mitochondrial succinate dehydrogenase which may increase the utilization of the liberated fatty acids. The results suggest that the erucic acid-induced lipidosis is prevented or eliminated by increased lipolysis and oxidation of fatty acids when such a diet is supplemented with carnitine and/or fish oil.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02021564
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  • 5
    Electronic Resource
    Electronic Resource
    Recent trends in Australian region tropical cyclone activity (1998)
    Springer
    Meteorology and atmospheric physics 65 (1998), S. 197-205 
    Details
    ISSN: 1436-5065
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geography , Physics
    Notes: Summary The number of tropical cyclones observed in the Australian region (south of equator; 105–160° E) has apparently declined since the start of reliable (satellite) observations in the 1969/70 season. However, the number of more intense cyclones (with minimum pressures dropping to 970 hPa or lower) has increased slightly. The numbers of weak (minimum pressures not dropping below 990 hPa) and moderate systems (minimum pressures between 970 and 990 hPa) have declined. Possible reasons for these different trends are discussed. The decline in the number of weaker cyclones may at least partly reflect improved understanding of the nature of some weak systems. The decline in the number of cyclones more intense than 990 hPa primarily reflects the downward trend in the Southern Oscillation Index (SOI). Previous work has demonstrated that the number of tropical cyclones observed in the Australian region each cyclone season is related to the value of the SOI prior to the start of the cyclone season. This relationship is clearest with the number of moderate cyclones. The SOI is only weakly related to the number of intense or weak cyclones. The increase in the number of intense cyclones is not attributable to the trend in the SOI. Nor is there clear reason, at present, to suspect that it is artificial (i.e., due to changes in observing or analysis techniques).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01030788
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  • 6
    Electronic Resource
    Electronic Resource
    Triazolo[4′,3′:4,5] [1,3,4]thiadiazolo[2,3-b]quinazolin-6-one (1983)
    Springer
    Monatshefte für Chemie 114 (1983), S. 339-342 
    Details
    ISSN: 1434-4475
    Keywords: Heterocycles ; Infrared ; 1H-NMR
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung 3-Methyl-6H-[1,2,4]triazolo[4′ ,3′ : 4,5] [1,3,4]thiadiazolo[2,3-b]chinazolin-6-on (6) wurde mittels Kondensation von Isatoesäureanhydrid (1) mit 4-Amino-5-mercapto-3-methyl[1,2,4]triazol (2) und anschließender Cyclisierung von Zwischenverbindung3 mit POCl3 und PCl3 dargestellt. Als Alternative konnte6 auch über die Kondensation von 3-Amino-2-mercapto-3H-chinazolin-4-on (7) mitN-Carbethoxyhydrazin in Gegenwart von HCl und anschließender Cyclisierung der Zwischenverbindung8 mit Essigsäure synthetisiert werden. Die Strukturen der Verbindungen wurden mittels IR,1H-NMR und Mikroanalyse nachgewiesen.
    Notes: Abstract 3-Methyl-6H-[1,2,4]triazolo[4′,3′: 4,5] [1,3,4]thiadiazolo[2,3-b]quinazolin-6-one (6) has been synthesized by the condensation of isatoic anhydride (1) with 4-amino-5-mercapto-3-methyl-[1,2,4]triazole (2) and final cyclisation of the intermediate3 with POCl3 and PCl3. Alternatively6 could also be synthesized by the condensation of 3-amino-2-mercapto-3H-quinazolin-4-one (7) withN-carbethoxy hydrazine in presence of hydrochloric acid and final cyclisation of the intermediate8 with acetic acid. The structures have been confirmed on the basis of IR, PMR and analytical results.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00798956
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  • 7
    Electronic Resource
    Electronic Resource
    Further observations on the chemistry of Pararosaniline-Feulgen staining (1976)
    Springer
    Histochemistry and cell biology 46 (1976), S. 147-160 
    Details
    ISSN: 1432-119X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology , Medicine
    Notes: Summary Pararosaniline-Feulgen staining of cells in suspension produces nucleus- and chromatin-specific fluorescence as well as color. Experiments were designed to test postulated reaction mechanisms responsible for the fluorescent staining with the nonfluorescent pararosaniline. The reduction in fluorescent-staining intensity by pretreatment of cells with 2.2×10−2M K2S2O5 tends to rule out the alkysulfonic acid pathway; conditions favoring the formation of this intermediate reduce staining intensity. The fluorescence enhancement, observed when cells stained in pararosaniline without K2S2O5 are post-treated with K2S2O5, suggests that there is an initial Schiff-base linkage between pararosaniline and an aldehyde of hydrolyzed DNA, and that this linkage is stabilized in the presence of K2S2O5. Microspectrofluorometer measurements of cells stained at various pararosaniline concentrations in 2.2×10−2M K2S2O5, show that the fluorescence emission maximum ranges from about 627 nm at 3.1×10−3M pararosaniline to about 604 nm at 3.1×10−5M. All of the employed staining protocols appear to produce the same fluorescent product, perhaps a heterocyclic pyronin analog formed from pararosaniline. Flow microfluorometric analysis of cells stained in suspension verified that the relative fluorescence intensity represents relative DNA content. Staining at reduced pararosaniline concentration (3.1×10−4M) reduces the coefficient of variation of the flow microfluorometric histograms, showing that maximum quantitation does not necessarily correlate with maximum staining intensity.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF02462739
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  • 8
    Electronic Resource
    Electronic Resource
    Processes and timescales in the evolution of a chemically zoned trachyte: Fogo A, Sao Miguel, Azores (1992)
    Springer
    Contributions to mineralogy and petrology 111 (1992), S. 311-328 
    Details
    ISSN: 1432-0967
    Source: Springer Online Journal Archives 1860-2000
    Topics: Geosciences
    Notes: Abstract U-series disequilibria analyses have been combined with chemical and petrographic analyses in order to assess both the timescales and processes involved in the formation of the chemically zoned Fogo A trachytes. Least squares major element modelling demonstrates that the mafic trachytes could have evolved from a parental alkali basalt via trachybasalt with ∼70% fractionation of augite (35–36%), plagioclase (23%), magnetite (16%), kaersutite (15%), olivine (8%) and apatite (2–3%). Derivation of the mafic trachytes from a basanite parent is inconsistent with calculated fractionation paths. Major and trace element variations in 25 pumice samples collected from throughout the stratigraphic extent of the Fogo A deposit show that the trachytes represent the inverted, extrusive equivalent of a strongly chemically zoned magma chamber. The zonation is attributed to 70–75% Rayleigh fractional crystallization of the observed phenocryst phases. Wallrock assimilation and magma mixing did not contribute significantly to the observed chemical trends. The maximum age of the Fogo A trachytic magma based on radioactive disequilibria between 230Th and 238U is 300000 years. However, a calculated model age suggests that the time of evolution of the Fogo A trachytes from a parent alkali basalt is only 90000 years. Constant element variations and Th-isotopic ratios in Fogo C, Fogo A and 1563 A.D. trachytes suggest that a single long-lived trachytic magma chamber has been the source of at least the past 15.2 Ka of trachytic volcanism from Agua de Pao. After each eruption an evolved cupola reformed and became zoned prior to the next eruption. The maximum time necessary to form the zonation is 4600 years, the time between the Fogo A and 1563 A.D. eruptions. Low (226Ra)/(230Th)i ratios in the Fogo A and 1563 A.D. trachytes suggest that alkali feldspar fractionation continued up to the time of the respective eruptions.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00311194
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  • 9
    Electronic Resource
    Electronic Resource
    Bucindolol: Effects on blood pressure, airways resistance and serum creatine phosphokinase (1984)
    Springer
    European journal of clinical pharmacology 27 (1984), S. 265-268 
    Details
    ISSN: 1432-1041
    Keywords: bucindolol ; beta-receptor blockade ; airways resistance ; creatine phosphokinase ; blood pressure ; ISA ; alpha-receptor blockade
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Medicine
    Notes: Summary The effect of bucindolol on pulse, blood pressure and airways resistance was studied in eight patients. One hour after 150 mg bucindolol, a significant decrease in supine, standing and post-exercise blood pressure was observed. No change in blood pressure occurred 10 to 14 h after doses ranging from 50–150 mg indicating that bucindolol has a relatively short duration of action. A dose related inhibition of excercise induced tachycardia was observed consistant with beta-receptor blocking activity. However, there was no change in the resting pulse indicating partial sympathomimetic activity. There was no increase in airways resistance at all doses of bucindolol. Serum creatine phosphokinase increased beyond normal limits in 3 out of 6 patients studied, probably due to a direct effect upon skeletal muscle.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00542157
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  • 10
    Electronic Resource
    Electronic Resource
    Genetic correlation and response to selection in simulated populations (1969)
    Springer
    Theoretical and applied genetics 39 (1969), S. 365-370 
    Details
    ISSN: 1432-2242
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Effects of truncation selection of a primary trait upon genetic correlation with a secondary trait were examined over 30 generations in genetic populations simulated by computer. Populations were 24 males and 24 females mated randomly with replacement; number of offspring was determined by intensity of selection. Each trait was controlled by 48 loci segregating independently, effects were equal at every locus, and gene frequency was arbitrarily set at 0.5 at each locus in the initial generation. All combinations of three genetic correlations, three intensities of selection, and three environmental variances were simulated. Gene action was additive. Genetic correlation was set by number of loci which affected both traits and was measured each generation as the product-moment correlation of genotypic values and estimated by two methods of combining phenotypic covariances between parent and offspring. Genetic correlations in each offspring generation remained consistently near initial correlations for all environmental variances when fraction of offspring saved as parents was as large as one-half. When the fraction of offspring saved was as small as one-fifth, genetic correlations decreased but most rapidly with heritability high and after the 15th generation of selection. Truncation selection caused genetic correlation to decrease in those offspring selected to become parents of the next generation. Amount of reduction depended on heritability of the selected trait rather than on degree of truncation selection. Estimates of genetic correlation from phenotypic covariances between parent and offspring fluctuated markedly from real correlations in the small populations simulated.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00290875
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