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  • 1
    Electronic Resource
    Electronic Resource
    Springer
    Applied physics 66 (1998), S. 1159-1163 
    ISSN: 1432-0630
    Keywords: PACS: 61.16.Ch; 68.35.Ct; 52.75.Rx; 62.40.+i; 61.72.Hh
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: rms (PFM), with no obvious anisotropic structures at the surface. After exposure of the B-doped diamond(100) to the H-plasma, the roughness increases dramatically, and pronounced anisotropic structures appear, these being closely aligned with the crystallographic axis’ and planes. An exposure for 3 minutes to the plasma leads to an increase of the roughness to 2–4 nmrms (STM), and a ‘brick-wall’ pattern appears, formed by weak cusps running along 〈110〉. Very frequently, the cusps are replaced by ‘negative’ pyramids that are bordered by {11X} facets. After an exposure of an additional 5 minutes, the surface roughness of the B-doped samples increases further to 20–40 nmrms (STM), and frequently exhibits a regular pattern with structures at a characteristic length scale of about 100 nm. Those structures are aligned approximately with 〈110〉 and they are faceted with faces of approximately {XX1}. These results will be discussed in terms of strain relaxation, similar to the surface roughening observed on SiGe/Si and anisotropic etching.
    Type of Medium: Electronic Resource
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  • 2
    ISSN: 1432-1076
    Keywords: Key words HIV-1 ; T-cells ; CD69 ; Activation ; Children
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Abstract We evaluated the use of a whole-blood assay that measures spontaneous and activation-induced CD69 expression on peripheral blood T-cells in vitro for assessment of T-cell function in HIV-1-infected paediatric patients. Heparinized venous blood from 28 HIV-1 positive children and adolescents and 23 healthy controls was incubated for 4 h with or without 5 μg/ml phytohaemagglutinin (PHA). Thereafter, analysis of CD69 expression on CD4+ and CD8+ T-cells was done by flow cytometry; simultaneously we determined CD4+ T-cell counts and plasma HIV-1 viral load. Neither spontaneous nor PHA-induced CD69 expression differed significantly between HIV-1 positive patients and healthy controls. However, T-cells from HIV-1 positive patients with plasma HIV-1 viral load levels above 70 × 103 copies/ml showed a higher spontaneous CD69 expression than T-cells from patients with lower plasma viral load levels in different stages of the disease. Antiretroviral treatment in four patients reduced spontaneous CD69 expression in CD4+ T-cells and PHA-induced CD69 expression in CD4+ and CD8+ T-cells significantly after 8 weeks of therapy. Conclusion Spontaneous and activation-induced expression of the early (activation) antigen CD69 on peripheral blood T-cells does not distinguish HIV-1 positive patients from HIV-1 negative healthy controls and is not correlated with peripheral blood CD4+ T-cell counts. This test may not be a reliable marker for functional T-cell deficiency during early stages of HIV disease. Increased spontaneous as well as PHA-induced CD69 expression on T-cells from HIV-1-infected children and adolescents in vitro may rather reflect HIV-induced pre-activation of T-cells in vivo.
    Type of Medium: Electronic Resource
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  • 3
    ISSN: 1573-4803
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract The sandwich structure of injection-moulded polypropylene parts with and without weld lines has been investigated using optical microscopy. X-ray scattering, and differential scanning calorimetry. It was found that the skin-layer thickness is strongly dependent on whether the mould is injected through one gate or through two gates. Samples containing a weld line show a much lower skin-layer thickness than samples without a weld line. This difference, however, depends strongly on the molecular weight of the polypropylene. The skin-layer thickness also varies along the flow path and decreases with increasing mould temperature. While most of the polypropylene crystallizes in the crystallographic α-modification, in the textured skin layer, some β-modification occurs. The β-crystallinity depends on the molecular weight but disappears in the weld line. X-ray investigations exhibited a bimodal crystal orientation in the skin layer, one with thec-axis oriented parallel to the flow direction, the second one with thea *-axis oriented parallel to the flow direction. The core exhibited only a weakc-axis orientation. In the skin, the metastable α1-modification was found.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    Colloid & polymer science 276 (1998), S. 747-749 
    ISSN: 1435-1536
    Keywords: Key words Polypropylene ; nucleation ; isothermal crystallization ; molecular fractionation
    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 nucleation frequency of isotactic polypropylene shows for certain molecular weight distributions during isothermal crystallization a “stepwise” development of the nuclei as a function of time. The resulting curve can be fitted by a superposition of exponential functions assuming a separate nucleation density for each nucleation step. The multimodal nucleation is discussed as a consequence of molecular fractionation effects during crystallization.
    Type of Medium: Electronic Resource
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  • 5
    ISSN: 1432-1173
    Keywords: Schlüsselwörter Besenreiser ; Sklerotherapie ; Blitzlampengepumpter gepulster Farbstofflaser ; Selektive Photothermolyse ; Key words Ectatic leg veins ; Sclerotherapy ; Flashlamp-pumped pulsed dye laser ; Selective photothermolysis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Summary A new flashlamp-pumped pulsed dye laser with 1,5 ms pulse length and tunable wavelengths between 585 and 600 nm (Candela ScleroPLUS) is now available for the treatment of ectatic leg veins. We evaluated 232 single test treatments using 595 and 600 nm wavelength in 75 test persons. For smaller vessels up to a diameter of 0,5 mm, treatments at 16 and 18 J/cm2 showed good results in 60 and 82% respectively; for vessels up to 1 mm in 27 and 33%. Treatment at 595 nm was a little more effective than at 600 nm. Larger vessels could not be treated effectively. The main side effects consisted in hyper- (34%) or hypopigmentation (30%). Thus, in addition to the usual sclerotherapy, this laser is a useful device for the treatment of leg vein ectasia.
    Notes: Zusammenfassung Zur Behandlung kosmetisch störender Besenreiser steht ein neuer blitzlampengepumpter gepulster Farstofflaser mit 1,5 ms Impulsdauer und verschiedenen Wellenlängen zwischen 585 und 600 nm zur Verfügung (Candela ScleroPLUS). Wir evaluierten 232 einmalige Probebehandlungen mit 595 und 600 nm Wellenlänge bei 75 Probanden. Bei kleineren Gefäßen bis 0,5 mm Durchmesser konnte bei Behandlung mit 16 bzw. 18 J/cm2 unter Zusammenfassung beider Wellenlängen in 60 bzw. 82% der Fälle ein zufriedenstellendes Ergebnis erzielt werden, bei Gefäßen bis 1 mm noch in knapp 27 bzw. 33%, wobei bei 595 nm tendenziell bessere Ergebnisse als bei 600 nm beobachtet werden konnten. Bei größeren Gefäßen zeigte sich kein deutlicher Erfolg. Die Nebenwirkungen beschränkten sich im wesentlichen auf Hyper- (34%) und Hypopigmentierungen (30%). Dieser Laser stellt somit eine sinnvolle Ergänzung zur herkömmlichen Sklerosierungstherapie dar.
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Springer
    Journal of materials science 16 (1997), S. 755-758 
    ISSN: 1573-4811
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract Abstracts are not published in this journal
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Journal of materials science 33 (1998), S. 1611-1618 
    ISSN: 1573-4803
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract The influence of two types of a styrene–ethylene/butylene–styrene (SEBS) triblock copolymer, one as received and the other functionalized with maleic anhydride, on model interfaces of high-density polyethylene (HDPE) and isotactic polypropylene (iPP) was investigated. Using a special preparation technique, it was possible to prevent gross interdiffusion at the interface and to attribute the problem to an adhesion-dominated phenomenon. The weak mechanical strength of the unmodified interfaces, iPP/iPP and HDPE/HDPE, was greatly improved by the triblock copolymer as was shown by the results of a T-peel test. The morphologies of the peeled surfaces of the modified and unmodified interfaces were analysed with light microscopy. The morphology of both model interface systems show differences, thus revealing different processes at the interfaces and thus different interactions of SEBS with iPP and HDPE and a different influence of the functionalization. The best results were achieved using the functionalized SEBS; the influence of functionalization was greater in the HDPE system. The results are in good agreement with a model proposed by the present authors elsewhere for the concentration-dependent role of SEBS in binary iPP/SEBS and ternary iPP/PE/SEBS blends.
    Type of Medium: Electronic Resource
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  • 8
    ISSN: 0044-8249
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Applied Polymer Science 59 (1996), S. 1891-1896 
    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 crystallization behavior of an isotactic polypropylene/linear low-density polyethylene blend (PP/LLDPE) that is modified with styrene-ethylene/butylene-styrene triblock copolymer (SEBS) has been investigated using differential thermoanalysis and polarization microscopy. SEBS, which enhances the impact resistance of the blend, has an effect on both the nucleation and crystallization kinetics of the polypropylene component. Nucleation half times, nucleation densities, and spherulite growth rates are influenced by the presence of the copolymer. It is found that SEBS, depending on its concentration in the blend, increases the adhesion between matrix and PE domains and acts simultaneously as the matrix reinforcer. © 1996 John Wiley & Sons, Inc.
    Additional Material: 8 Ill.
    Type of Medium: Electronic Resource
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  • 10
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Angewandte Chemie International Edition in English 34 (1995), S. 600-601 
    ISSN: 0570-0833
    Keywords: Chemistry ; General Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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