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  • 1
    Electronic Resource
    Electronic Resource
    An instrument for the heat flux measurement from a contour of a surface with uniform temperature (1994)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 65 (1994), S. 689-694 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: An instrument for the measurement of the heat flux distribution along an internal or external contour of a surface with a uniform temperature is described. The main element in this instrument is an electrically heated narrow nickel/chromium ribbon which is mounted flush with, but thermally and electrically insulated from, walls on all sides. The walls are separately heated and are made of a highly conducting material (e.g., aluminum) to ensure a uniform temperature. Differential thermocouples are used to measure the temperature difference between the walls and Ni/Cr ribbon at various positions along the ribbon. The ribbon power is adjusted until the differential temperature is nulled at a particular position on the ribbon. Since conduction along the ribbon is small, the electrical power divided by the sensor area is a direct measure of the surface heat flux at the nulled position. This makes it possible to measure the local time-average heat flux at various positions along a contour of a surface inside a circular duct. The time constant in this application was 13 s. An uncertainty analysis shows that this instrument has an uncertainty of ±3.84% for a convective heat flux on the order of 900 W/m2.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1145140
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  • 2
    Electronic Resource
    Electronic Resource
    Improvements in a new technique for measuring and mapping heat transfer coefficients (1986)
    [S.l.] : American Institute of Physics (AIP)
    Review of Scientific Instruments 57 (1986), S. 650-654 
    Details
    ISSN: 1089-7623
    Source: AIP Digital Archive
    Topics: Physics , Electrical Engineering, Measurement and Control Technology
    Notes: Two important improvements in a new technique for measuring and mapping local heat transfer coefficients are described. The first improvement involves the use of a new encapsulated thermochromic liquid crystal which has better stability and a narrower bandwidth than the cholesteric crystals previously used. The second important improvement is in the packaging arrangement. In this new arrangement, useful for gas flows, the liquid crystal is applied directly on the surface of an electrically conducting gold coating used as an electric heater, and is essentially in direct contact with the fluid. The encapsulated liquid crystal used in this study was applied directly to the gold surface without affecting the electrical characteristics of the gold coating. This new packaging arrangement has two advantages. First, no correction for the temperature drop across the plastic substrate is required. Second, a significant increase in the maximum detectable frequency is predicted.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.1138883
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  • 3
    Electronic Resource
    Electronic Resource
    Influence of different physicochemical conditions on the release of indium oxine from nanocapsules (1998)
    Hoboken, NJ : Wiley-Blackwell
    Journal of Biomedical Materials Research 39 (1998), S. 588-593 
    Details
    ISSN: 0021-9304
    Keywords: polyepsiloncaprolactone nanocapsules ; indium oxine ; in vitro release kinetics ; esterases ; Chemistry ; Polymer and Materials Science
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Medicine , Technology
    Notes: The main purpose of this study was to determine the influence of factors (pH, enzymes, etc.) chosen partially to mimic in vivo conditions on the release of a model drug, indium oxine, from polyepsiloncaprolactone (PCL) nanocapsules in vitro. A nanocapsule suspension, an emulsion (O/W), and a solution in olive oil were prepared in order to compare the release of a radioactive tracer, indium oxine, as a function of time by an in vitro dialysis method. Nanocapsules were prepared by interfacial deposition of PCL and characterized by particle size distribution (laser light scattering) and determination of the polymer molecular weight by gel permeation chromatography (GPC). The results of this study suggest that the partition coefficient between the acceptor medium and the olive oil is the major parameter governing the release of the isotope, at least in the absence of significant enzyme activity. The PCL wall of nanocapsules is a barrier that does not seem to retard the release of indium. The addition of porcine liver esterases accelerated the degradation of PCL. This study confirms that the release of a drug from nanocapsules may be very different depending on the in vivo location, that is, the administration site. © 1998 John Wiley & Sons, Inc. J Biomed Mater Res, 39, 588-593, 1998.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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  • 4
    Electronic Resource
    Electronic Resource
    Ion structural studies by ion kinetic energy spectrometry: [C7H7]+, [C7H8]+·, [C7H7OCH3]+· (1973)
    Chichester : Wiley-Blackwell
    Biological Mass Spectrometry 7 (1973), S. 1303-1312 
    Details
    ISSN: 0030-493X
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The use of kinetic energy release measurements in the structural characterization of ions formed in the mass spectrometer and in the determination of fragmentation mechanisms is demonstrated. In combination with information on the mode of energy partitioning in some of these reactions this allows the following conclusions: (i) The metastable [C7H8]8· ions formed from toluene, cyclohepatatriene, n-butylbenzene, the three methyl anisoles, methyl tropyl ether and benzyl methyl ether all undergo loss of H· from a common structure. (ii) The metastable [C7H7]+ ions generated from the same sources and from benzyl bromide, benzyl alcohol, p-xylene and ethylbenzene appear to undergo loss of acetylene from both the benzylic and the tropylium structures. (iii) The metastable [C7H7OCH3]+· ether molecular ions undergo loss of CH3· by two types of mechanism, simple cleavage to give the aryloxy cation (not observed for benzyl methyl ether) and a rearrangement process which appears to lead to protonated tropone as the product. (iv) Loss of formaldehyde from the metastable [C7H7OCH3]+· molecular ions involves hydrogen transfer via competitive 4- and 5-membered cyclic transition states in the case of the anisoles and in the case of methyl tropyl ether, while for benzyl methyl ether, hydrogen transfer in the nonisomerized molecular ion occurs via a 4-membered cyclic transition state to yield the cycloheptatriene molecular ion.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/oms.1210071110
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  • 5
    Electronic Resource
    Electronic Resource
    The reactive states of ions: Octatrienes and dimethyl substituted cyclohexadienes (1975)
    Chichester : Wiley-Blackwell
    Biological Mass Spectrometry 10 (1975), S. 1075-1083 
    Details
    ISSN: 0030-493X
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The principal decomposition routes of molecular ions of cis, cis, cis-2,4,6-octatriene, cis, cis, trans-2,4,6-octatriene, trans, cis, trans-2,4,6-octatriene, trans-5,6-dimethyl-1,3-cyclohexadiene and cis-5,6-dimethyl-1,3-cyclohexadiene were studied using ion kinetic spectroscopy. The loss of radicals from [M]+· appears to proceed via a ground state, while loss of a neutral molecule appears to involve either complete equilibration of structure within the system or both ground state and excited state pathways.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/oms.1210101205
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  • 6
    Electronic Resource
    Electronic Resource
    Ionic dehydration reactions: The effect of location of the activated complex on kinetic energy release (1977)
    Chichester : Wiley-Blackwell
    Biological Mass Spectrometry 12 (1977), S. 258-260 
    Details
    ISSN: 0030-493X
    Keywords: Chemistry ; Analytical Chemistry and Spectroscopy
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: A broad range of kinetic energy release has been found for the 1,4 elimination of water in a series of ortho substituted benzyl alcohols and benzoic acids. It is suggested that the trend reflects, in part, the position of the activated complex on the reaction coordinate. More specifically, reactions which proceed via an ‘early’ transition state release only small quantities of energy, whereas those processes occurring ‘later’ release a larger fraction of the available energy. Consequently, the o- methyl derivatives give large kinetic energy release compared to o- amino or hydroxy substituted compounds. Father verification is obtained from the small kinetic energy release observed for the 1,4 ionic dehydration in simple,acyclic alcohols.
    Additional Material: 2 Tab.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/oms.1210120415
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