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  • 1
    Electronic Resource
    Electronic Resource
    Thickening process of polyethylene single crystals at an early stage of annealing (1984)
    Springer
    Colloid & polymer science 262 (1984), S. 597-604 
    Details
    ISSN: 1435-1536
    Keywords: position sensitive proportional counter ; small and wide angle X-ray scattering ; polyethylene single crystal ; annealing ; thickening
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract By the use of a position sensitive proportional counter, changes in small and wide angle X-ray scattering during annealing of polyethylene single crystal mats were measured from the start in successive spans of very short measuring time. At high temperatures, the long period relating to stacking of lamellae rapidly increased at an early stage, passed through a plateau, and thereafter again increased gradually. With a decrease in annealing temperature, the amount of its first rapid increase was reduced and the plateau changed into an ascending slope. At much lower annealing temperatures, the long period increased following the logt law after an induction time. The integral breadth of a peak corresponding to the long period first increased rapidly, simultaneously with the rapid increase in the long period, and thereafter decreased. Wide angle X-ray measurement showed that the integrated intensity of 110 reflection first decreased and then increased during annealing at high temperatures. This fall and rise process was more marked, when the annealing temperature is higher and the initial thickness of lamellae is smaller. From these observations, it was inferred that in the thickening process, stacking order of lamellae at first decreased because of rapid reorganization due to partial melting or melt-recrystallization and subsequently increased through increasing evenness of lamellar thickness.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01452449
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  • 2
    Electronic Resource
    Electronic Resource
    Thickening process of polyethylene single crystals at an early stage of annealing (1985)
    Springer
    Colloid & polymer science 263 (1985), S. 293-300 
    Details
    ISSN: 1435-1536
    Keywords: Polyethylene single crystal ; annealing ; thickening ; computer simulation ; small angle X-ray scattering
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract The thickening process of polyethylene single crystals was simulated with computer by the Monte Carlo method. According to the experimental results in the previous report, the time dependence of the long period changed greatly with annealing temperature; at lower temperatures the long period increased gradually, while at high temperatures the long period rapidly increased at a very early stage of annealing and then increased gradually after passing through a plateau. Through computer simulation, it was shown that such a great change in the time dependence of the long period with annealing temperature can be explained by combining two mechanisms: (A) sliding diffusion of molecular segments along the chain axis and (B) local melt-recrystallization (namely, local melting followed by recystallization).
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01412244
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    Paper (German National Licenses)
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  • 3
    Electronic Resource
    Electronic Resource
    Microscopic hematuria (1992)
    Springer
    International urogynecology journal 3 (1992), S. 64-70 
    Details
    ISSN: 1433-3023
    Keywords: Asymptomatic ; Microhematuria
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract Asymptomatic microhematuria is not a rare phenomenon among apparently healthy individuals, and the incidence of such hematuria increases significantly with age. Some investigators report that the cause of hematuria is renal glomerular disease in more than 50% of patients, and urological malignancies in 1.0%–13%. On initial examination, urine sediments must be searched for evidence of renal glomerular disease, such as RBC casts and dysmorphic RBCs. If the patients were diagnosed to have glomerular disease, follow-up studies, without any extended examination or therapy are recommended, because their prognosis is usually favorable. The next step is to perform thorough urological examinations, including urine cytology, cystoscopy, abdominal ultrasound, and intravenous pyelography, to detect serious underlying disease. Even if no significant findings were observed after the extensive urological examinations, careful follow-up studies should be performed at 6–12-month intervals for 3 years, using the same methods.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00372658
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  • 4
    Electronic Resource
    Electronic Resource
    Mechanochemical polymerization of acetylene (1984)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 29 (1984), S. 3445-3455 
    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: Gamma alumina, γ-Al2O3, was fractured in an atmosphere of acetylene monomer at room temperature to test whether they would be polymerized by mechanochemistry method on the surface of the alumina. The experimental results were obtained by serveral different methods, including CP-MAS 13C-NMR, ESR, pressure drop measurements of the monomer, optical absorption spectroscopy, and solvancy. The results proved the mechanochemical polymerization of acetylene monomer on surfaces of the fractured alumina. Several other combinations of either silica and acetylene monomer or polymers and acetylene monomer were tested for mechanochemical polymerization. This process proceeded with less efficiency in the silica system but no mechanochemical polymerization of acetylene was found in the combinations of the polymers and acetylene monomer.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1984.070291121
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  • 5
    Electronic Resource
    Electronic Resource
    Polymerization of ethylene induced by fractured metallic oxides. III. Factors affecting the polymerization (1984)
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 29 (1984), S. 3401-3408 
    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: Mechanochemical polymerization of ethylene was found to be induced by fracture of γ-alumina under quite low pressure and room temperature. The factors to control the polymerization yield, for example, calcination temperature of the alumina, spin concentration after ball milling, milling time, and changes of acidity before and after the fracture, were investigated in order to know the polymerization mechanism. It was found that the polymerization yield did correlate not with the spin concentration responsible to paramagnetic species produced by the fracture, but the calcination temperature of the γ-alumina and the milling time. The resultant polymeric material on the fractured alumina was extracted alumina was extracted with solvents, and the fraction extracted with petroleum ether was characterized using GC and GC mass spectrometer. The results indicated that odd-numbered linear hydrocarbons were produced, although the major products of this polymerization were even-numbered. It is concluded from the accumulated experimental results that a carbonium ion mechanism rather than radical mechanism is probable for the mechanochemical polymerization induced by fracture of γ-alumina.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/app.1984.070291117
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  • 6
    Electronic Resource
    Electronic Resource
    Concerning carbon-13 n.m.r. spectroscopy of 5β-hydroxylated phytoecdysones (1977)
    Chichester : Wiley-Blackwell
    Organic Magnetic Resonance 10 (1977), S. 255-257 
    Details
    ISSN: 0030-4921
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The 13C n.m.r. spectra of the 5β-hydroxylated phytoecdysones polypodine B, muristerone A and kaladasterone are presented and briefly discussed together with the spectrum of makisterone A. Comparisons with previously reported spectra of ecdysone, ecdysterone and poststerone are made and allow a correction for the C-20/C-24 assignment for ecdysone.
    Additional Material: 1 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/mrc.1270100159
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