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  • Chemistry  (9)
  • Borax-H2O2 system  (1)
  • Female epispadias  (1)
  • Incontinence  (1)
  • 1
    Electronic Resource
    Electronic Resource
    Phase transfer catalyzed oxidation of ketones with borax-H2O2 (1995)
    Springer
    Monatshefte für Chemie 126 (1995), S. 647-652 
    Details
    ISSN: 1434-4475
    Keywords: Baeyer-Villiger oxidation ; Phase transfer catalysis ; Borax-H2O2 system
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Zusammenfassung In Wasserstoffperoxid (30%) gelöstes Borax bildet Peroxyverbindungen, die durch Schütteln in die organische Phase zweiphasiger Systeme übergeführt werden können. Der Transferprozeß wird durch die Zugabe von katalytischen MengenBTEAC gefördert. Die zweiphasigen Systeme wurden zurBaeyer-Villiger — Oxidation einiger in Wasser unlöslicher Ketone eingesetzt und die Auswirkung der Variation verschiedener Parameter (z.B. Temperatur, Zeit, Menge an H2O2 etc.) untersucht. Unter dem Einfluß höherer Temperature (ca. 80°C) wurde vollständige Umsetzung innerhalb von 2–4 h erreicht. Die Ergebnisse zeigen, daß die genannte Reaktion unter geeigneten Bedingungen von synthetischem Wert zur Oxidation säureempfindlicher Ketone unter Verwendung billiger und leicht verfügbarer Reagenzien ist.
    Notes: Summary Borax forms peroxy species when dissolved in 30% hydrogen peroxide which can be transferred into the organic phase when biphase mixtures are agitated. The addition of a catalytic amount ofBTEAC promotes the transfer. This biphase system was used for theBaeyer-Villiger oxidation of several ketones insoluble in water. Effects of changing various parameters,e.g. temperature, time, amount of H2O2 etc. were investigated. At higher temperature (ca. 80°C), 100% conversion could be achieved in 2–4h. The results show that under appropriate conditions this reaction is of synthetic value for the oxidation of acid-sensitive ketones using inexpensive and easily available reagents.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00807154
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  • 2
    Electronic Resource
    Electronic Resource
    Total genitourinary reconstruction in adult female epispadias: A report of 2 cases and literature review (1998)
    Springer
    International urogynecology journal 9 (1998), S. 55-57 
    Details
    ISSN: 1433-3023
    Keywords: Female epispadias ; Incontinence
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Female incontinent episadias is a very rare congenital anomaly presenting in childhood. We report 2 cases of adults presenting with this anomaly. These were treated by total genitourinary reconstruction in a single stage using a combined perineal abdominal approach, with satisfactory results. We recommend this technique as the procedure of choice in adults presenting with this rare anomaly.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01900545
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  • 3
    Electronic Resource
    Electronic Resource
    Dielectric behavior of DNA-Proflavine complex (1973)
    New York : Wiley-Blackwell
    Biopolymers 12 (1973), S. 1047-1052 
    Details
    ISSN: 0006-3525
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The dielectric relaxation of namtive DNA and DNA-proflavine complexes at different DNA phosphate (P) to dye (D) ratios, were investigated in the frequency range 100 c/sec to 100 Kc/sec. The proflavine molecules were found to have a profound effect on the static dielectric constant and the relaxation time of the polymers. The static dielectric constant was oberserved to decrese with increasing level of added proflavine. At P/D = 1, the variation of dielectric constant with frequency was small. Relaxation time (τ) was greater for the DNA-proflavine complexes compared to that for free DNA, Maximum value of the relaxation time was obtained at P/D = 10. The increase in the relaxation time and decrease in the static dielectric constant were attributed to the increase in length and meutralization of surface charges of the DNA molecules, respectively, as aresult of proflavine binding.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bip.1973.360120508
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  • 4
    Electronic Resource
    Electronic Resource
    On the electric polarization of DNA (1974)
    New York : Wiley-Blackwell
    Biopolymers 13 (1974), S. 1549-1556 
    Details
    ISSN: 0006-3525
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Dielectric dispersion of DNA was studied in the frequency range 100 Hz-100 kHz at four different temperatures (6-30°C). The dielectric increment ε0-ε∞ increased with the rise of temperature. The relaxation time, on the other hand, decreased. Both the increase in dielectric increment and the decrease in relaxation time could not be explained on the basis of the counterion polarization theory. Dipole moment was estimated from Kirkwood theory. It was found to decrease systematically with temperature. Even at 0°C there was a dipole moment of 104D.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bip.1974.360130804
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  • 5
    Electronic Resource
    Electronic Resource
    Dielectric behavior of DNA - dye complex - II (1974)
    New York : Wiley-Blackwell
    Biopolymers 13 (1974), S. 391-400 
    Details
    ISSN: 0006-3525
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The dielectric relaxation of native DNA and the effect of aminoacridine dyes, such as acridine orange (AO), proflavine (PF), and ethidium bromide (EB) have been investigated at different molar DNA phosphate (P) to dye (D) ratios in the frequency range 100 Hz-100 kHz. The static dielectric constant was observed to decrease with increasing binding of aminoacridines. This was interpreted as arising from the neutralization of the surface changes of the DNA molecules as a result of dye binding. At any P/D ratio the extent of charge neutralization was greatest for AO and least for the EB-DNA complex. The relaxation time (τ) for dye-bound DNA was greater compared to that for native DNA. This increase in τ was ascribed to the increase in the length of the dye-bound DNA. The maximum value of τ occurred at P/D = 20, 10, and 2 for AO-, PF-, and EB-treated DNA, respectively. The variation of τ at various levels of binding gave a qualitative idea about the conformational changes of DNA due to its binding with the dyes.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/bip.1974.360130214
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  • 6
    Electronic Resource
    Electronic Resource
    Functionalization of crosslinked polystyrene by radiation-induced grafting (1996)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 62 (1996), S. 955-955 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1996.070620611
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  • 7
    Electronic Resource
    Electronic Resource
    Functionalization of crosslinked polystyrene by radiation-induced grafting (1996)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 60 (1996), S. 1601-1607 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: γ-ray irradiated beads of poly(styrene-divinylbenzene) (PS-DVB) have been graft copoly-merized with polyacrylic acid. Preirradiated PS-DVB beads were refluxed with acrylic acid in water, benzene, or toluene. Percentage of grafting was studied under various reaction parameters like total dose, reaction time, and molar concentration. Effects of reaction media, temperature of reaction, and presence of Mohr salt on the percentage of grafting were also studied. From the swelling property of PS-DVB beads in DMF and dichloro-methane, it appeared that no appreciable cross-linking had occurred in the process of grafting. © 1996 John Wiley & Sons, Inc.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    Designing a support for borohydride through grafting onto crosslinked polyvinylpyrrolidone (1996)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 62 (1996), S. 1793-1798 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Crosslinked polyvinylpyrrolidone (PVPy) was grafted with polyvinylpyridine by irradiating the polymer beads in air from a Co60 γ-radiation source and then heating with 4-vinylpyridine (4-VP) in water. The percentage of grafting was studied as a function of various reaction parameters and was determined from the increase in weight of PVPy and from the estimation of pyridine rings introduced into the polymer. PVPy-g-poly(4-VP) was treated with sodium in ethanol, which is known to reduce pyridine into piperidine together with small amounts of 1,2,5,6-tetrahydropyridine. On methylation with dimethyl sulfate and alkali, these are further converted into N,N-dimethylpiperidinium groups. The dimethylpiperidinium graft was used to support borohydride ions and the graft copolymer was shown to cleanly reduce several carbonyl compounds to the corresponding alcohols. © 1996 John Wiley & Sons, Inc.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    Functionalization of poly(vinyl chloride) through radiation-induced grafting (1995)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 58 (1995), S. 1735-1739 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Poly(vinyl chloride) was irradiated in air with γ-rays. The hydroperoxidized poly(vinyl chloride) when heated with acrylic acid in water was grafted with poly(acrylic acid), thus introducing the elements of glutaric acid on the polymer. Percentage weight gain was investigated as a function of total dose, monomer concentration, and time of reaction. The effect of adding methanol to water as a medium of reaction was studied in terms of percentage weight gain on grafting. © 1995 John Wiley & Sons, Inc.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1995.070581011
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  • 10
    Electronic Resource
    Electronic Resource
    Solid-phase peptide synthesis on a novel hydrogenolysable linker-resin combination (1995)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 56 (1995), S. 1127-1131 
    Details
    ISSN: 0021-8995
    Keywords: Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: The propensity of benzyloxycarbonylamide group towards clean and rapid hydrogenolysis was exploited in designing a linker for solid phase peptide synthesis on a copoly(styrene-divinylbenzene) resin support. Hydroxymethyl copoly(styrene-divinylbenzene) on treatment with 4-nitrophenyl chloroformate gave a resin which possessed benzyl 4-nitrophenyl carbonate pendants. These reacted with the α-amino group of Boc-Lys-OMe, resulting in the attachment of the latter through its side chain to the resin by a benzyloxycarbonylamide linkage. This was used to extend the peptide chain from the α-amino end of lysine by Bocmethodology. The peptide was released from the resin through palladium acetate-ammonium formate-based transfer hydrogenolysis. The usefulness of this linker was demonstrated by synthesizing several small peptides terminating in lysine. © 1995 John Wiley & Sons, Inc.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1995.070560912
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