Bibliothek

feed icon rss

Ihre E-Mail wurde erfolgreich gesendet. Bitte prüfen Sie Ihren Maileingang.

Leider ist ein Fehler beim E-Mail-Versand aufgetreten. Bitte versuchen Sie es erneut.

Vorgang fortführen?

Exportieren
Filter
  • Polymer and Materials Science  (6)
  • Diurnal changes  (1)
  • 1
    Digitale Medien
    Digitale Medien
    Springer
    Cell & tissue research 118 (1971), S. 310-314 
    ISSN: 1432-0878
    Schlagwort(e): Pineal ; Mouse ; Glycogen ; Diurnal changes ; Quantitative histochemistry
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Summary The amount of glycogen in pineal cells of 60-day-old male dd-mice was estimated at various times of the day by means of a quantitative histochemical method. The level of glycogen stores varied periodically in correlation with the environmental light-dark cycle, being lowest at the end of the daily dark period and highest at the end of the daily light period. The size of pineal cells also varied diurnally, being largest at 9 AM, two hours after the beginning of the daily photoperiod, and smallest at 9 PM, two hours after the end of the daily photoperiod; however, these changes were less marked than those in glycogen level. The changes in cell size were delayed by a few hours as compared with changes in glycogen stores. In blinded male mice of the same age, neither pineal glycogen level nor pineal cell size varied in response to diurnal lighting.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 2
    Digitale Medien
    Digitale Medien
    New York : Wiley-Blackwell
    Biopolymers 11 (1972), S. 1583-1592 
    ISSN: 0006-3525
    Schlagwort(e): Chemistry ; Polymer and Materials Science
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Circular dichroism spectra of acridine orange bound to E. coli tRNA were studied at varying tRNA phosphate-to-dye (P/D) ratios for both unfractionated and purified materials in the absence of Mg++. From the rather discrete features exhibited in the circular dichroism spectra three types of interactions were observed: (1) A high P/D ratio such as 75.2 or 49.8 indicates the interaction between the nucleotide base and dye molecule. The spectra with a large positive peak at 515 mμ are, however, quite different from that of DNA-AO complex under similar conditions. (2) With an intermediate P/D ratio (26.5 to 9.6) dye molecules bound strongly to the polynucleotide chain. (3) With low P/D ratios (≤7.5) the interaction appears to be due to the stacked dye molecules in the single-stranded part of tRNA. The spectra of the third group have an isobestic point at 477 mμ. Below a P/D ratio of 4 the spectrum shows one positive and two negative bands which may be the characteristics of circular dichroism of stacked dyes in polynucleotide chain.Although no drastic change in the conformation of tRNA itself was detectable in the presence of Mg++ in the ultraviolet region, a dramatic change was observed in the circular dichroism of tRNA-acridine orange complex when Mg++ concentration was increased to 10-3M. It was inferred that certain conformational changes other than simple hydrogen bond formation occured in tRNA molecules at this high Mg++ concentration, so that the amount of bound dye in the stacking condition was increased through the transition.
    Zusätzliches Material: 7 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 3
    Digitale Medien
    Digitale Medien
    Bognor Regis [u.a.] : Wiley-Blackwell
    Journal of Polymer Science Part A: Polymer Chemistry 30 (1992), S. 1567-1573 
    ISSN: 0887-624X
    Schlagwort(e): nickel ; coupling polymerization ; aromatic dichloride ; polyamide ; poly[(2,5-dimethyl-1,4-piperazinediyl) (4,4′-biphenyldicarbonyl)] ; Chemistry ; Polymer and Materials Science
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Notizen: Four aryl dichlorides containing secondary amide structural units as monomers were synthesized from substituted piperazines and chlorobenzoyl chlorides. Polyamides were prepared by the nickel-catalyzed coupling polymerization of these monomers. Polymerizations were carried out in N-methyl-2-pyrrolidinone (NMP) in the presence of nickel chloride, zinc, triphenylphosphine, and bipyridine, and resulted in polyamides with inherent viscosities up to 0.38 dL/g under mild conditions. The structure of polymer was determined by IR and 13C-NMR spectroscopies. The polyamide, poly[4,4′-biphenyldicarbonyl (2,5-dimethylpiperazine)] 6d, was readily soluble in dipolar aprotic solvents and chloroform. Thermogravimetry of polyamides, poly[(4,4′-biphenyldicarbonyl piperazine)]s 6, showed 10% weight loss at around 425 and 450°C in air and under nitrogen, respectively. © 1992 John Wiley & Sons, Inc.
    Zusätzliches Material: 4 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 4
    Digitale Medien
    Digitale Medien
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 40 (1990), S. 2101-2112 
    ISSN: 0021-8995
    Schlagwort(e): Chemistry ; Polymer and Materials Science
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Maschinenbau , Physik
    Notizen: The zone-drawing method has been applied to prepare ultra-high modulus polyvinyl alcohol fibers. First, the suitable temperature for zone-drawing was decided. In the first zone drawing, when drawing temperature was as high as near melting point, the highest draw ratio and modulus were obtained. The modulus was further increased by repeating zone drawing and heat treatment. In this study, the highest dynamic moduli were 115 GPa at room temperature and 42 GPa at 200°C. The fiber has a sharp melting peak that appeared at 246°C and a small peak at 260°C in the DSC curve.
    Zusätzliches Material: 12 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 5
    Digitale Medien
    Digitale Medien
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 97 (1966), S. 128-138 
    ISSN: 0025-116X
    Schlagwort(e): Chemistry ; Polymer and Materials Science
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Physik
    Beschreibung / Inhaltsverzeichnis: Die Copolymerisation von Methacrylsäuremethylester mit dem Glycidester derselben Säure und die Kinetik der Reaktion des Copolymeren mit sekundären Aminen wurden untersucht. Die Reaktionsfähigkeit dreier Modellsubstanzen und des Copolymeren wurden verglichen. Die Modellverbindungen zeigten eine isokinetische Beziehung; die isokinetische Temperatur betrug 331°K.
    Notizen: The copolymerization of methyl methacrylate with glycidyl methacrylate and the kinetic of the reaction of copolymer with secondary amines were investigated. Three model compounds of the copolymer were prepared in order to compare their reactivity with that of copolymer. It was found that these compounds have an isokinetic relationship and the isokinetic temperature was 331°K.
    Zusätzliches Material: 5 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 6
    Digitale Medien
    Digitale Medien
    New York : Wiley-Blackwell
    Die Makromolekulare Chemie 104 (1967), S. 26-36 
    ISSN: 0025-116X
    Schlagwort(e): Chemistry ; Polymer and Materials Science
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie , Physik
    Beschreibung / Inhaltsverzeichnis: Die Taktizitäten von Poly(glycidylmethacrylaten), die radikalisch im Temperaturbereich von -78 bis 60°C in einigen Lösungsmitteln und in Substanz polymerisiert wurden werden beschrieben. Selbst bei niedrigerer Temperatur ist das Redoxsystem Diisopropylperoxydicarbonat/Dimethylanilin beim Monomeren wirksam. Die Taktizitäten der Polymeren werden mittels NMR-Spektren bestimmt. Die Entropie- und Enthalpiedifferenzen der Aktivierung des isotaktischen und syndiotaktischen Wachstums (Δ(ΔS) bzw. Δ(ΔH)) werden berechnet. Die Werte für Δ(ΔH) werden durch die Polymerisationsbedingungen nicht merkbar beeinflußt und sind etwas größer als jene für die Methacrylsäuremethylesterpolymerisation.
    Notizen: The tacticities of poly(glycidyl methacrylate) prepared by radical polymerization at temperatures in the range from -78 to 60°C in several solvents or in bulk are described. The redox system diisopropylperoxy dicarbonate/dimethylaniline was found to polymerize this monomer effectively even at low temperature. The tacticities were determined by NMR spectroscopy. The difference of entropy Δ(ΔSNippon Oils & Fats Co., Ltd. (Chiyoda-ku, Tokyo, Japan)) and enthalpy Δ(ΔH) of activation between isotactic and syndiotactic propagations were calculated. The values of Δ(ΔH) were found not to be affected essentially by polymerization conditions and to be slightly larger than that of methyl methacrylate polymerization.
    Zusätzliches Material: 3 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
  • 7
    Digitale Medien
    Digitale Medien
    New York : Wiley-Blackwell
    Journal of Polymer Science Part B: Polymer Letters 5 (1967), S. 29-37 
    ISSN: 0449-2986
    Schlagwort(e): Chemistry ; Polymer and Materials Science
    Quelle: Wiley InterScience Backfile Collection 1832-2000
    Thema: Chemie und Pharmazie
    Zusätzliches Material: 2 Ill.
    Materialart: Digitale Medien
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
Schließen ⊗
Diese Webseite nutzt Cookies und das Analyse-Tool Matomo. Weitere Informationen finden Sie hier...