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  • 1
    Digitale Medien
    Digitale Medien
    Photochemical additions of alkenes to phthalimides. Mechanistic investigations on the stereochemistry of alkene additions and the effect of aryl substituents on the regiochemistry of alkene additions (1983)
    s.l. : American Chemical Society
    The @journal of organic chemistry 48 (1983), S. 2981-2989 
    Details
    ISSN: 1520-6904
    Quelle: ACS Legacy Archives
    Thema: Chemie und Pharmazie
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1021/jo00166a009
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  • 2
    Digitale Medien
    Digitale Medien
    Statistical modeling of capture, association, and exit-channel dynamics in the CH3+/CH3CN system (1993)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 98 (1993), S. 1944-1956 
    Details
    ISSN: 1089-7690
    Quelle: AIP Digital Archive
    Thema: Physik , Chemie und Pharmazie
    Notizen: The ion–molecule reaction CH3++CH3CN is known to have an association channel leading to CH3CNCH3+ in competition with the exothermic binary channels H2CN++C2H4 and C2H5++HCN. This reaction has been modeled using a master equation treatment incorporating weak collisions. The parameters required for the Rice–Ramsberger–Kassel–Marcus (RRKM) treatment have been found from an ab initio investigation of the CH3+/CH3CN energy surface. A means of including capture rate coefficients in the RRKM approach is developed, in which only the hindered dipole rotation is coupled with the reaction coordinate at large separations. Existing experimental data from ion cyclotron resonance (ICR) spectroscopy and a selected ion flow tube are fitted by the model in the pressure range 10−7–0.3 Torr. The low pressure experimental results are accounted for by weak collisions of the complex with the bath gas (when M=He, 〈ΔEdown(approximately-greater-than) and 〈ΔRdown(approximately-greater-than)∼100 cm−1) corresponding to a collision efficiency β=0.05 for M=He and 0.14 for M=CH3CN. Unimolecular rate coefficients for the (CH3CNCH3+)* complex are calculated for all product channels at a range of temperatures from 300 to 600 K. The rate coefficient for radiative stabilization was found to be 225 s−1 at the conditions of the ICR experiment. The average lifetime of the complex was calculated to vary between 29 μs at 600 K to 0.47 ms at 300 K and the termolecular association rates from 3.4×10−24–9.8×10−23 cm6 s−1 (M=He) and from 6.7×10−23–2.2×10−21 cm6 s−1 (M=CH3CN) over the temperature range 600–300 K.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.464228
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  • 3
    Digitale Medien
    Digitale Medien
    Magnetoelastic dependence of switching field in TbFe–FeCo giant magnetostrictive spring-magnet multilayers (2000)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 87 (2000), S. 5780-5782 
    Details
    ISSN: 1089-7550
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: The role of magneto-elastic interactions in controlling the magnitude of switching field and coercivity is investigated using sputter-deposited TbFe/FeCo multilayers. In the absence of long-range anisotropy in amorphous TbFe layers, along with negligible magneto-crystalline anisotropy in FeCo layers, reversal behavior in these multilayers is largely determined by stress-induced anisotropy. Results show that magneto-elastic constraints at the TbFe–FeCo interfaces arising due to different values of saturation magnetostriction in adjacent layers lead to biaxial stresses. This manifests itself as highly square and similar M–H loops measured in different directions in the plane of the films. The measured values of coercivity in these films (between 4.5 and 7.0 mT) are found to be in close agreement with theoretical coercivity values predicted on the basis of biaxial stress-induced anisotropy. Biaxial stresses resulting in corresponding stress-induced anisotropy were found to have interesting consequences vis-à-vis magnetization reversal. In particular, self-organized domain patterns are formed during reversal which are mediated by local stress state in the films. © 2000 American Institute of Physics.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.372520
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  • 4
    Digitale Medien
    Digitale Medien
    Broadband optical limiting based on excited state absorption in Pt:ethynyl (2000)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 88 (2000), S. 1726-1732 
    Details
    ISSN: 1089-7550
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: Analytical, numerical, and experimental studies of the nonlinear transmission of a Pt:ethynyl compound have been carried out. Based on a model for the electronic transitions derived from earlier work, optical limiting behavior that is both broadband across the visible and effective over a range of pulse lengths, is predicted. Detailed experimental results are presented which exhibit many of the theoretically predicted characteristics, including a broadband nonlinear response from 450 to 700 nm. © 2000 American Institute of Physics.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.1303054
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  • 5
    Digitale Medien
    Digitale Medien
    An objective assessment of physiotherapy for female genuine stress incontinence (1987)
    Oxford, UK : Blackwell Publishing Ltd
    BJOG 94 (1987), S. 0 
    Details
    ISSN: 1471-0528
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Medizin
    Notizen: Sixty women with genuine stress incontinence were consecutively assigned to one of four physiotherapy groups who were treated for 6 weeks by either (1) pelvic floor exercises (PFE) in hospital; (2) PFE and faradism; (3) PFE and interferential therapy; (4) PFE at home. Assessment before and after treatment was by 7-day bladder charts, urethral pressure profiles and perineometry. Approximately two-thirds of the hospital-treated patients (groups 1, 2 and 3) experienced marked or moderate subjective improvement and at 6 months, 27% were dry or almost dry. There was little difference in outcome between groups 1, 2 and 3 but hospital-based therapy was more effective than home treatment. Statistical analyses showed that there were significant improvements in the objective indices measured in the 45 hospital-treated patients. Successful treatment was more likely in younger patients, in those with lesser degrees of genuine stress incontinence and those who had had no previous pelvic floor surgery.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1111/j.1471-0528.1987.tb03153.x
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  • 6
    Digitale Medien
    Digitale Medien
    Treatment with oral piperazine oestrone sulphate for genuine stress incontinence in postmenopausal women (1987)
    Oxford, UK : Blackwell Publishing Ltd
    BJOG 94 (1987), S. 0 
    Details
    ISSN: 1471-0528
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Medizin
    Notizen: The use of oestrogens in the treatment of genuine stress incontinence was assessed by a double-blind prospective trial in 36 postmenopausal women with genuine stress incontinence who received 3 months of cyclical treatment with either piperazine oestrone sulphate or a matching placebo. Patients were assessed subjectively and objectively before and after treatment by 7-day bladder charts, urethral pressure profiles (UPP), the Urilos nappy test, vaginal cytology and hormone assays (plasma oestrogens and gonadotrophins). There was no statistical difference in the subjective response to treatment between the two groups. After 6 weeks of treatment there was a greater reduction in the number of pad changes/24 h in the oestrogen-treated patients that approached statistical significance but, because of a marked response in the placebo group, this difference was not significant after 3 months of treatment. There were also no significant differences between the two groups with respect to the UPP or Urilos measurements but the vaginal cytology and hormone profiles were significantly affected by oestrogens. In view of the possible risks of oestrogen therapy its use in genuine stress incontinence is limited.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1111/j.1471-0528.1987.tb03152.x
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  • 7
    Digitale Medien
    Digitale Medien
    Smoking Is Not a Predictor of Mortality and Morbidity Following Coronary Artery Bypass Grafting (1996)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of cardiac surgery 11 (1996), S. 0 
    Details
    ISSN: 1540-8191
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Medizin
    Notizen: Abstract Background: The objective of this study was to determine the significant differences in preoperative and operative characteristics, and postoperative outcomes in patients having coronary artery bypass grafting (CABG) who are smokers and in those who are not smokers. Methods: Data were collected prospectively in all (2916) patients having their first CABG. The patients were cared for in a regional medical center by private physicians. No operations were denied because of smoking status. Smokers differed from nonsmokers in several characteristics. Results: Analysis of morbidity and mortality showed no instance in which smokers fared worse than nonsmokers. Stepwise logistic regression analysis showed that smoking was not predictive of mortality. Smoking was not predictive of morbidity except that it was predictive of less probability of need for intra-aortic balloon pump (7.5% in non-smokers and 4.7% in smokers). We then created groups of smokers and nonsmokers that were individually matched for age and sex. Analysis of the matched groups of smokers and nonsmokers showed that there was no significant difference in the incidence or magnitude of preoperative and operative factors except that recent myocardial infarction was more common in smokers. Nonsmokers had greater weight, body mass index (obesity), and ejection fraction. There was no difference in smokers and nonsmokers in mortality or morbidity at the 99% confidence level. Conclusion: We conclude that there is no need to delay CABG for the patients who are smokers.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1111/j.1540-8191.1996.tb00067.x
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  • 8
    Digitale Medien
    Digitale Medien
    Biochemistry of Sporulation in Oocysts of Eimeria acervulina (1961)
    Oxford, UK : Blackwell Publishing Ltd
    The @journal of eukaryotic microbiology 8 (1961), S. 0 
    Details
    ISSN: 1550-7408
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Biologie
    Notizen: Oocysts of Eimeria acervulina Tyzzer, 1929 were collected at the time of their first massive discharge into the chick intestine, and isolated in the cold by means of continuous centrifugal flotation in high-density media. Maximum numbers (90%) of sporoblastic oocysts were obtained by incubating at 30°C for 10 hr and sporulation was considered complete within 20 hr. The initial Qo2 (dry-weight basis) of 9.5 decreased linearly to 〈 i/3 this value in 20 hr, and more slowly thereafter to very low levels. The QCO2 was higher than Qo2 only during the first 10 hr. A 15% decrease in dry weight in 15 hr was due chiefly to disappearance of alkali-stable carbohydrate, probably identical with glycogen. In the later stages carbohydrate was resynthesized. Lipids were not oxidized during sporoblast formation, but disappeared rapidly betweem 10 and 30 hr. Total nitrogen remained constant, indirect evidence suggesting that protein was not used to supply oxidative energy The change-over from carbohydrate to fat metabolism corresponded with observed changes in the respiratory quotient, and also with near-completion of sporulation. Apparently carbohydrate provided the energy needed for the earlier stages of sporulation, whereas oxidation of lipids supported the teal stages as well as the metabolism during dormancy.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1111/j.1550-7408.1961.tb01236.x
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  • 9
    Digitale Medien
    Digitale Medien
    THE ROLE OF MOLYBDENUM AND FLAVIN IN HYDROGENASE (1954)
    s.l. : American Chemical Society
    Journal of the American Chemical Society 76 (1954), S. 3355-3356 
    Details
    ISSN: 1520-5126
    Quelle: ACS Legacy Archives
    Thema: Chemie und Pharmazie
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1021/ja01641a090
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  • 10
    Digitale Medien
    Digitale Medien
    Nitrous Oxide Inhibition of Nitrogen Fixation by Azotobacter1 (1952)
    s.l. : American Chemical Society
    Journal of the American Chemical Society 74 (1952), S. 3101-3103 
    Details
    ISSN: 1520-5126
    Quelle: ACS Legacy Archives
    Thema: Chemie und Pharmazie
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1021/ja01132a044
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