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  • 1
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    Journal of chemical documentation 11 (1971), S. 106-110 
    ISSN: 1520-5142
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 58 (1985), S. 4670-4678 
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: There is increasing technological interest in using Cl2 and Cl-containing compounds in the dry plasma etching of III–V semiconductors. This paper presents a study of the ion-assisted etching of GaAs by Cl2 using a modulated ion beam technique to gain insight into the kinetic mechanism of this process. The etching rate increases with increasing ion energy (0.3–3 kV) and depends linearly on ion flux (1.0–10.0×1014 ions cm2 s). The etching rate increases with increasing Cl2 pressure up to a saturation limit near 2×10−6 Torr. This saturation limit is independent of the ion flux coincident on the surface within the range studied. The ion-enhanced etching rate decreases with increasing sample temperature over the range 300–500 K. Major etch products are AsCl3 and GaCl2 (and possibly GaCl), and the time dependence of the increase in these mass spectrometer signals following the initiation of the ion pulse is consistent with all of the products having a most probable translational energy of ∼0.14 eV. There is an additional delay in the appearance of the AsCl3 signal which roughly corresponds to a first order reaction with an associated time constant of 1.1 ms. One possible kinetic mechanism for the ion-enhanced etching is proposed which involves the surface reactions of Ga and AsCl with adsorbed chlorine. In this model, the ∼1 ms delay in the appearance of the AsCl3 is attributed to the lifetime of potential energy excitation caused by the ion.
    Type of Medium: Electronic Resource
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  • 3
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    Unknown
    Boston, Mass., etc. : Periodicals Archive Online (PAO)
    The North American Review. 156 (1893:Jan./June) 439 
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  • 4
    Electronic Resource
    Electronic Resource
    Springer
    The European physical journal 269 (1974), S. 41-46 
    ISSN: 1434-601X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract The neutron flux distribution on the wall of a toroidal CTR device with strongly elongated cross section is calculated. On the inner and outer cylindrical walls (belt-pinch device) the flux distribution has a plateau region with a half-width equal to about the height of the plasma. The maximum flux is found on the outer cylinder and in the symmetry plane (z 0=0). The neutron flux asymmetry and reductionη of the mean wall loading are determined. For standard data anη of 57% is computed. This is mainly due to the flux profiles on the cylindrical walls and does not depend sensitively on the toroidal curvature. For standard parameters the inner cylinder absorbs 22.6%, the outer cylinder 68.6% and the end plates together 8.8% of the total neutron emission. The corresponding values for a straight device with the same coil and plasma cross section are 44%, 44% and 12%. A reduction of toroidal curvature diminishes flux asymmetry between the inner and outer cylinders. The maximum flux and minimumη-value are obtained at a large torus radius equal to two times the coil width. For small aspect ratios (R t W0.5) the neutron flux through the inner cylinder becomes so small that its interior may be filled with a material other than a blanket material, e.g. with an iron core.
    Type of Medium: Electronic Resource
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  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Monatshefte für Chemie 104 (1973), S. 1138-1138 
    ISSN: 1434-4475
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
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  • 6
    Electronic Resource
    Electronic Resource
    Springer
    European food research and technology 150 (1972), S. 87-93 
    ISSN: 1438-2385
    Source: Springer Online Journal Archives 1860-2000
    Topics: Process Engineering, Biotechnology, Nutrition Technology
    Description / Table of Contents: Zusammenfassung Bei der Ermittlung der Bleilässigkeit von Bedarfsgegenständen erfolgt zunächst eine Säurebehandlung des Gegenstandes, dann wird im Säureauszug der Bleigehalt ermittelt. Es werden verschiedene Verfahren der Säurebehandlung aufgeführt, wobei der Kaltextraktion mit 4 % iger Essigsäure über 24 Std der Vorzug gegeben wird. Die Bleibestimmung im essigsauren Auszug wird mit Hilfe der AAS durchgeführt. Das Chromatverfahren nach DIN 51031 wird in einigen Punkten geändert. Nach dem abgewandelten Chromatverfahren werden die gleichen Bleigehalte wie mit Hilfe der AAS erhalten. Sodann wird auf die rechtliche Beurteilung der vom Gebrauchsgegenstand abgegebenen Bleimenge unter Berücksichtigung der internationalen Gesetzgebung hingewiesen. Die Rechtslage in der BRD ist unbefriedigend. Es wird vorgeschlagen, die im Essigauszug enthaltenen Bleimengen auf die den Speisen zugewandte Oberfläche des Gebrauchsgegenstandes zu beziehen und eine Höchstmenge von 2 mg Blei je dm2 Oberfläche zu tolerieren.
    Notes: Summary The determination of lead solubility from ceramics is realized by extraction with acetic acid (4 % w/w in water, 24 hours at room temperature) and by following determination of lead by atomic absorption. The supplementary analysis by iodometric determination as lead chromate (DIN 51031) is varied in some points, so that both ways give the same results. The legal valuation of lead solubility is discussed in an international view.
    Type of Medium: Electronic Resource
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  • 7
    Electronic Resource
    Electronic Resource
    Springer
    Archives of orthopaedic and trauma surgery 69 (1971), S. 246-263 
    ISSN: 1434-3916
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Description / Table of Contents: Résumé Avec une machine universelle servant à mesurer la tension, on a examiné les particularités mécaniques de l'aponévrose humaine par rapport à l'âge des malades, à la conservation et au trajet des faisceaux. On a pu en déduire les mesures mécaniques suivantes: l'indice de la tangente, la résistance de la tension, l'allongement dû à la force maximale, la montée de la courbe de relaxation. Avec l'avancemant en âge on pouvait oberver un accroissement de la fixité de l'indice de la tangente. Les prélévement naturels ainsi que les prélévements cialites montraient une tendance à des veleurs plus hautes de résistance et de l'indice de la tangente au contraire des prélévements lyophilisés. Les grandeurs mécaniques de résistance montraient une dépendance nette de l'angle du trajet des faisceaux et de la direction de la tension. On a discuté du rapport des transformations mécaniques constatées suivant l'âge et des examens physico-cliniques et électroniques-microscopiques chez d'autres. On a montré la wécessité de connaître les particularites mécaniques de l'aponéarose pour l'emploi clinique comme greffe homo- et autologue.
    Abstract: Zusammenfassung Mit dem Universalprüfgerät (Modell Instron TT-MC) wurde menschliche Fascie auf ihre alters-, konservierungs- und faserverlaufsbedingten mechanischen Eigenschaften untersucht. Folgende mechanische Kenngrößen wurden bestimmt: Tangentenmodul, Zugfestigkeit, Dehnung bei Höchstkraft, Steigung der Relaxationskurve. — Eine zunehmende Verfestigung konnte mit Zunahme des Lebensalters festgestellt werden. — Eine Tendenz zu höheren Zugfestigkeits-und Tangentenmodulwerten zeigten die nativen sowie cialit-konservierten im Gegensatz zu den lyophilisierten Proben. Die mechanischen Kenngrößen zeigten eine deutliche Abhängigkeit vom Winkel zwischen Faserverlauf und Zugrichtung. Ein Zusammenhang der festgestellten altersabhängigen mechanischen Veränderungen mit physiko-chemischen und elektronenmikroskopischen Untersuchungen anderer Autoren wird diskutiert. Auf die Notwendigkeit der Kenntnis der mechanischen Eigenschaften der Fascie bei ihrer klinischen Verwendung als homo- und autologes Transplantat wird hingewiesen.
    Notes: Summary Human fascia has been examined with the aid of a universal test equipment as to its mechanical properties in relation to age, conservation and texture. The following mechanical characteristics have been determined: Tangent module, firmness, extension under appliance of maximal force and increase of the relaxation curve. An increasing hardening could be stated with advancing age. A tendency towards higher values of firmness and tangent modules became evident with native and cialit conserved samples in contrast to such treated by means of lyophilization. The mechanical characteristics revealed a definite dependence from the angle between texture and direction of extension. The correlation of the stated mechanical changes depending on age is discussed together with physico-chemical and electronmicroscopic investigations of other authors. It is pointed to the necessity of knowledge on the mechanical properties of fascia when using it clinically as a homologous or heterologous transplant.
    Type of Medium: Electronic Resource
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  • 8
    Electronic Resource
    Electronic Resource
    [s.l.] : Nature Publishing Group
    Nature 319 (1986), S. 474-477 
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Western basin cold core eddies are spawned from Gulf Stream meanders that intensify, grow into loops, and pinch off from the main stream to form rings of current that wander independently in the waters to the south and south-east of the Gulf Stream3. They are readily distinguishable from other ...
    Type of Medium: Electronic Resource
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  • 9
    Electronic Resource
    Electronic Resource
    Springer
    Development genes and evolution 168 (1971), S. 359-361 
    ISSN: 1432-041X
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Description / Table of Contents: Zusammenfassung Isolierte Körperteile vonLineus sanguineus wurden in Seewasser gehalten, das unterschiedliche Konzentrationen (1,9, 0,95 und 0,48 μg/ml) von Actinomycin-D enthielt. Nach 4, 5, 6 und 10 Tagen wurden die Regenerate histologisch und histochemisch (Glykogen, Glucose-6-phosphat-Dehydrogenase und RNS) untersucht. In Abhängigkeit von der Actinomycin-D-Konzentration werden bestimmte Phasen der Regeneration gehemmt; dabei sind Proliferationsprozesse weniger empfindlich als Differenzierungsprozesse. Histochemisch werden bei Hemmung der wachstumsaktiven Areale die im Normalfall zu beobachtenden stofflichen Merkmale: Glykogeneinlagerung und nachfolgender Anstieg der G-6-P-DH-Aktivität und der RNS-Konzentration vermißt.
    Notes: Summary Fragments ofLineus sanguineus were incubated in seawater, which contained different concentrations of actinomycin-D (1.9 μg/ml, 0.95 μg/ml and 0.48 μg/ml). After 4, 5, 6 and 10 days the regenerates were studied by histological and histochemical methods (glycogen, glucose-6-phosphate-dehydrogenase and RNA). Corresponding to actinomycin-D concentration certain phases of regeneration are inhibited. The phases of proliferation are less sensitive to actinomycin-D than the phases of differentiation. If morphogenetic areas are inhibited, the normally demonstrable histochemical characteristics: accumulation of glycogen and later, the increase of G-6-P-DH activity and RNA concentration do not appear.
    Type of Medium: Electronic Resource
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  • 10
    ISSN: 1432-1939
    Keywords: Net-building behaviour ; Development ; O2-deficiency tolerance ; Hydropsyche ; River Rhine
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Tolerance, growth and development of H. contubernalis and H. pellucidula were analyzed at different O2-concentrations to determine the species specific potency amplitude in relation to O2-concentration. In addition netbouilding behaviour was compared at different O2-concentrations and current velocities. Under anaerobic conditions slightly greater tolerance was observed in H. contubernalis than in H. pellucidula. But at a higher O2-concentration H. contubernalis showed a distinctly higher O2-deficiency tolerance than H. pellucidula in relation to net-building activity, growth and development. In addition, more than 50% of H. contubernalis instars built capture nets with regular meshes at an O2-saturation of only 30% (15°C). High growth rates were also found at 50% O2-saturation and more than half the larvae developed into imagos. In addition to diminished net-spinning activity the mean growth rate started to decrease at an O2-saturation of 70% to 38% and the development into an imago was not possible in H. pellucidula. Because H. contubernalis corresponds to a regulative type, being able to maintain a high level of netbuilding activity, growth rate and development over a wide range (50% to 100% O2-saturation). On the other hand H. pellucidula corresponds to a conform type, because physiological efficiency decreases rapidly with falling O2-concentration, so that development into an imago is no longer possible below 85% O2-saturation. Positive correlation between net-spinning activity and tested current velocity between 10 cm/s and 25 cm/s (15°C) was found in H. pellucidula. H. contubernalis showed no change in net-building activity, over this range of current velocity. H. contubernalis can be classified as an euryoecious species with a great potency amplitude in relation to O2-concentration and current velocity. The high tolerance to O2-deficiency conditions probably allowed the early recolonization of the Mittel-and Niederrhein when a distinct O2-deficit (mean 29%, max 56%) could still be measured. H. contubernalis can be considered a bioindicator of O2-deficiency situations. Undisturbed development of H. pellucidula in this section of the river requires a further improvement in O2-content.
    Type of Medium: Electronic Resource
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