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  • 1
    Digitale Medien
    Digitale Medien
    Analytical and numerical analysis of Debye–Ramm's equation for the polarization density distribution in polar materials (1994)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 76 (1994), S. 5399-5410 
    Details
    ISSN: 1089-7550
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: Due to dipole interaction, the molecular polarization brought about by an external field is significantly lower in condensed matter (liquids) than in a gas. In addition to this, the response of interacting dipoles to stepwise changes of the external field does not follow a simple time exponential. Instead, a spectrum of relaxation times is required to describe such a response. Debye and Ramm [Ann. Phys. 28, 28 (1937)] have attempted to describe the effects associated with rotational hindrances due to dipole-dipole interaction by the following differential equation: ∂f/∂t =(kT/ρ)Δf+(1/ρ)div(f grad u), where f denotes the distribution function specifying the number of dipoles pointing in a certain solid angle, t the time, ρ a friction coefficient, and u the potential of the forces acting on the dipoles. The latter quantity depends both on the external field and on the contribution from the dipole-dipole interaction (internal field). Although unable to solve the above equation explicitly, Debye and Ramm (DR) made some predictions about the solution, concluding, among other things, that the inclusion of an internal field E would yield a process with a discrete spectrum of relaxation times. Finding such prospect highly interesting, we subjected the DR equation to a close study using some advanced mathematical tools (Fourier integral operators etc.). Contrary to the conclusions of DR, we found that the above equation cannot be solved in the way originally described, and that the conjectured eigenfunctions and eigenvalues do not exist. Furthermore, we show that, in contrast to DR's statements, the above equation is not solved by certain classical expressions relating to free-rotating dipoles (no internal field). The lack of physical content of this equation appears to be due to a number of not permissible simplifications.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.357195
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  • 2
    Digitale Medien
    Digitale Medien
    Structure of the reducing end-groups in spruce xylan
    Amsterdam : Elsevier
    Carbohydrate Research 111 (1983), S. 283-288 
    Details
    ISSN: 0008-6215
    Quelle: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Thema: Chemie und Pharmazie
    Materialart: Digitale Medien
    URL: http://linkinghub.elsevier.com/retrieve/pii/0008-6215(83)88312-8
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  • 3
    Digitale Medien
    Digitale Medien
    Drug prescription attitudes and behaviour of general practitioners (1995)
    Springer
    European journal of clinical pharmacology 47 (1995), S. 381-387 
    Details
    ISSN: 1432-1041
    Schlagwort(e): General practice ; Drug prescription attitude ; post-graduate education ; clinical pharmacology ; drug information
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Notizen: Abstract A producer-independent, problem-oriented, group-education programme with 2-day meetings on drug treatment in primary health care (PHC) was developed and evaluated. Initially, it was tested on a selected group of general practitioners (district physicians), using a non-exposed group as control. A comprehensive questionnaire was used to test changes in attitudes. There was a significant change in attitudes concerning both general opinions on drugs and drug use, on information about drug treatment, and on use of drugs in selected therapeutic areas. Also, the district physicians became more critical towards information from pharmaceutical companies. Prescribing patterns tended to change in accordance with the attitude changes. Subsequently, the programme was offered to all district physicians (about 550) in the southern Swedish health care region for a 10-year period, with 20–25 district physicians per 2-day meeting. The impact of the programme on the prescribing of a selected group of drugs (antibiotics) was assessed by voluntary registration of prescription by the participants, by regional prescription analyses and by analyses of drug sales data. There were significant, consistent, and sustained changes in the prescribing of antibiotics. The study supports the view that, if drug prescribing in general practice is to be improved, producer-independent, problem-oriented, face-to-face, small-group education on drug treatment is worthwhile.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00196849
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  • 4
    Digitale Medien
    Digitale Medien
    Angiotensin-converting enzyme inhibition, cough and the serum concentration of substance P (1988)
    Springer
    European journal of clinical pharmacology 34 (1988), S. 649-650 
    Details
    ISSN: 1432-1041
    Schlagwort(e): enalapril ; cough ; substance P ; ACE inhibitor ; adverse effects
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Chemie und Pharmazie , Medizin
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00615232
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