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  • 1
    Electronic Resource
    Electronic Resource
    Free convective heat transfer and criterion of onset of free convection in a horizontal melt layer of ice heated by upper rigid surface (1977)
    Springer
    Heat and mass transfer 10 (1977), S. 269-279 
    Details
    ISSN: 1432-1181
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Description / Table of Contents: Zusammenfassung Es handelt sich um eine experimentelle und analytische Untersuchung über den Einfluß der Dichteinversion von Wasser auf den Wärmeübergang bei freier Konvektion und den Konvektionseinsatz in einer waagerechten Schicht aus geschmolzenem Eis bei Heizung von oben durch eine starre Fläche. Die Temperaturen dieser Fläche variierten von 1°C bis 15°C bei Rayleigh-Zahlen von 2 × 102 bis 1 × 105. Das Ergebnis zeigt den grundsätzlichen Einfluß der Dichteinversion in der geschmolzenen Schicht; Konvektionseinsatz und Wärme-übergang hängen stark von der Temperatur der oberen Begrenzung ab, sofern diese kleiner oder gleich 8° C ist, im deutlichen Gegensatz zu normalen Fluiden.
    Notes: Abstract An experimental and analytical investigation pertaining to the effect of density inversion of water on the free convective heat transfer and the onset of free convection in a horizontal melt layer of ice heated by upper rigid surface is carried out. Temperatures of the upper surface are varied from 1°C to 15°C, with Rayleigh number ranging from 2 × 102 to 1 × 105. From the present study, it can be demonstrated both experimentally and analytically that the density inversion of water plays an influential role in such a melt layer and the onset of free convection and the free convective heat transfer are considerably affected by the temperature of upper rigid surface T2, in the case of T2 ≤ 8° C, unlike the results obtained for common fluids without density inversion.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00998728
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  • 2
    Electronic Resource
    Electronic Resource
    Melting of horizontal ice layer from above by combined effect of temperature and concentration of aqua-solvent (1987)
    Springer
    Heat and mass transfer 21 (1987), S. 227-232 
    Details
    ISSN: 1432-1181
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Description / Table of Contents: Zusammenfassung Der Aufsatz behandelt das Aufschmelzen einer horizontalen Eisschicht von oben mittels einer wäßrigen Lösung niedrigen Gefrierpunktes. Die in diesem Experiment verwendeten Lösungen sind Natriumchlorid NaCl, Kalziumchlorid CaCl2, Magnesiumchlorid MgCl2 und Harnsäure CO(NH2)2. Die Oberfläche der wäßrigen Lösung und der Schmelze wurde mit einer Infrarotlampe beheizt, deren Temperatur bei 8–40
    Notes: Abstract This paper is concerned with the melting of horizontal ice layer from above by aqua-solvent with low solidification point. The solute used in this experiment are Sodium chloride NaCl, Calcium chloride CaCl2, Magnesium chloride MgCl2, and Urea CO(NH2)2- The upper surface of aqua-solvent melt layer is heated by an infrared lamp, whose temperature is in the range of about 8
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01004025
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  • 3
    Electronic Resource
    Electronic Resource
    Room-temperature exciton optical absorption peaks in InGaAsP/InP multiple quantum wells (1989)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 54 (1989), S. 1353-1355 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We grew In1−xGaxAsyP1−y/InP quantum wells (QWs) by low-pressure metalorganic vapor phase epitaxy. The In1−xGaxAsyP1−y layer was closely lattice matched to InP with a composition of y=0.9 (x=0.47y). We investigated structural imperfections such as composition fluctuations, interface roughness, and nonperiodicity analyzing the low-temperature photoluminescence linewidth. We found that the InGaAsP layer composition fluctuated, causing about 5 meV inhomogeneity in the exciton energy level in QWs wider than about 3 nm. Since we obtained very smooth interfaces with less than one monolayer of fluctuation and excellent periodicity by lowering growth temperature to 570 °C, the inhomogeneity of the exciton energy level could be held at 6 meV for 20-period 10-nm multiple QWs. As a result, despite composition fluctuations, a clear room-temperature exciton optical absorption peak was observed at 1.5 μm for the first time to our knowledge.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.100713
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  • 4
    Electronic Resource
    Electronic Resource
    Frequency characteristics of the Mn-doped InP p-n junction (1988)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 63 (1988), S. 1961-1963 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Admittance spectroscopy is applied to the analysis of the thermal properties of the Mn acceptor-doped InP grown by liquid-phase epitaxy. The thermal activation energy and capture cross section are determined as ΔET=183 meV and σp=1.8×10−13 cm2, respectively. The cutoff frequency of the emission of holes from the Mn acceptor is 1 GHz at 300 K. It is shown that the small signal frequency characteristic of a buried heterostructure laser is improved at frequencies f〉1 GHz by using the Mn-doped p-InP layer for the current blocking region.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.341094
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  • 5
    Electronic Resource
    Electronic Resource
    Fe-doped semi-insulating InP grown by chloride vapor-phase epitaxy (1987)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 61 (1987), S. 4698-4700 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Fe-doped semi-insulating (SI) InP layers have been grown using chloride vapor-phase epitaxy for the first time. Fe-doping was carried out by introducing FeCl2 to the growth region, bypassing the source region. The FeCl2 was formed by etching a pure metallic Fe source by HCl vapor. The resistivity of the SI-InP epitaxial layers was evaluated by measuring current-voltage characteristics, and a high value of 4×108 Ω cm was obtained. The semi-insulating current blocking was maintained up to an applied voltage of nearly 30 V, even at 110 °C, with a layer 4.3 μm thick.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.338385
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  • 6
    Electronic Resource
    Electronic Resource
    Liquid phase epitaxial growth of Fe-doped semi-insulating InGaAsP lattice matched to InP over the entire composition range (1988)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 53 (1988), S. 574-576 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Fe-doped semi-insulating In1−x Gax Asy P1−y (0≤y≤1, y=2.2x) epitaxial layers lattice matched to InP with nearly intrinsic carrier concentrations have been successfully grown over the entire composition range by liquid phase epitaxy. Maximum resistivities as high as 8×107 Ω cm for InP, 2×105 Ω cm for InGaAsP (y=0.57), and 2×103 Ω cm for InGaAs (y=1) have been achieved. The critical growth temperature necessary to obtain semi-insulating layers significantly decreased as the composition was varied from y=0 to y=1. The Fe doping characteristics are well defined by the composition dependence of the Fe distribution coefficient.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.99861
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  • 7
    Electronic Resource
    Electronic Resource
    Evaluation of exciton absorption peak broadening factors in InGaAsP/InP multiple quantum wells (1988)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 53 (1988), S. 2290-2292 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: We evaluated the magnitude of broadening factors of ground-state exciton absorption peaks in In1−xGaxAsyP1−y/InP (x=0.47y) multiple quantum wells (MQW's) with about 10 nm wells. The absorption peaks broadened with a decrease of y. Analyzing the absorption peak broadening with increasing temperature, the thermal broadening factor at 300 K was found to be about 9 meV and composition independent. Analyzing the photoluminescence linewidth at 4.2 K, it was found that composition fluctuations in the well caused an inhomogeneity of the exciton energy level of 4.4 meV for the y=1.0 MQW and 7.5 meV for the y=0.6 MQW, being the greatest contributors to inhomogeneous broadening. We conclude that the exciton absorption peak broadening with a decrease of y is primarily due to the increase of composition fluctuations.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.100256
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  • 8
    Electronic Resource
    Electronic Resource
    Exact determination of superlattice structures by small-angle x-ray diffraction method (1988)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 52 (1988), S. 742-744 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The structure of In1−xGaxAsyP1−y/InP superlattices (x=0.27 and y=0.60) is investigated by small-angle x-ray diffraction method. The interference peaks due to the superlattice structure were clearly observed up to the 6th order. The period of the superlattice was determined from the angular positions of the peaks using the modified Bragg's law. By analyzing the diffraction patterns of the first and the secondary peaks according to the optical multilayer theory, the thickness of each component (In1−xGaxAsyP1−y and InP) was uniquely determined within an error of ±1 A(ring). This method can be used to determine any type of superlattice structure.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.99342
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  • 9
    Electronic Resource
    Electronic Resource
    Radiative melting of ice layer adhering to a vertical surface (1979)
    Springer
    Heat and mass transfer 12 (1979), S. 137-144 
    Details
    ISSN: 1432-1181
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Description / Table of Contents: Zusammenfassung Diese Arbeit behandelt das Schmelzen einer senkrechten Eisschicht auf einer Unterlage mit Hilfe von Halogen-Lampen mit einem hohen Anteil an kurzen Wellen und Nichromheizern mit einem hohen Anteil an langen Wellen. Aus diesen Versuchen läßt sich ableiten, daß die Heizung durch kurzwellige Strahlung ein eigentümliches Schmelzverhalten mit sehr rauher Oberfläche hervorruft, verursacht durch Schmelzen an den Korngrenzen der Eisoberfläche. Bei langwelliger Heizung wird die Oberfläche sehr glatt. Die Abschmelzrate einer Klareisschicht bei kurzwelliger Heizung durch Halogen-Lampen ist geringer als die einer Opaleisschicht wegen des besseren Eindringens der kurzen Wellen in das klare Eis. Der Temperaturanstieg an der Grenze Eis — Unterlage bietet die Möglichkeit der Enteisung von Bauteilen, die der atmosphärischen Vereisung ausgesetzt sind. Es folgt, daß die Abschmelzrate einer Eisschicht, numerisch vorausberechnet werden kann, indem man das Bandmodell des Extinktions- und des Absorptionskoeffizienten dieser Arbeit verwendet.
    Notes: Abstract This paper is concerned with melting of a vertical ice layer adhering to the substrate by using radiating heat source of halogen lamps having a large fraction of short wave beam or nichrome heater having a comparatively large fraction of long wave one. From the present experimental results, it can be seen that the heating of short wave radiation produces a peculiar melting behavior of strongly rough melting-surface due to the internal melting at the grain boundary of ice-surface. On the other hand, for the case of long wave radiation the melting-surface becomes very smooth. The melting rate of clear ice layer by short wave radiation obtained from halogen lamps is smaller than that of cloudy ice layer due to the good penetration of short wave fraction through the clear ice layer. Moreover, the raising of temperature of ice-substrate interface could offer a feasibility of removing ice layer from the structure subject to atmospheric icing. Concludingly, it is clarified that the melting rate of ice layer could be predicted numerically by using the band model of extinction coefficient or absorption coefficient presented in this study.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01002329
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  • 10
    Electronic Resource
    Electronic Resource
    Radiative melting of a horizontal clear ice layer (1978)
    Springer
    Heat and mass transfer 11 (1978), S. 207-216 
    Details
    ISSN: 1432-1181
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Description / Table of Contents: Zusammenfassung Eine waagerechte Klareisschicht, die auf einer Unterlage aufgefroren war, wurde durch kurzwellige Strahlung, Ähnlich der Sonnenstrahlung, zum Schmelzen gebracht, um die Entfernung von Eis nach atmosphÄrischer Vereisung zu untersuchen. Die Strahlungsquelle war eine 300 Watt-Halogenlampe mit einer Farbtemperatur von 3200 Kelvin bei 100 Volt. Als typische Erscheinung wurde ein “Rückseiten-Schmelzen” gefunden, im übrigen sind die vorausberechneten Schmelzraten an der Ober- und der Unterseite durch aufgenommene oder durchgelassene Strahlungsenergie in guter übereinstimmung mit den Messungen.
    Notes: Abstract In this paper the horizontal layer of clear ice sticking to the substrate is melted by comparatively short wave radiation similar to solar radiation for the purpose of removing ice from the surface of the material subject to atmospheric icing. The radiating source used for melting is 300 wattages halogen lamps whose color temperature is 3200
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01805661
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