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  • 2005-2009  (2)
  • 1985-1989  (18)
  • 1975-1979  (6)
  • 1
    Digitale Medien
    Digitale Medien
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 60 (1986), S. 334-337 
    ISSN: 1089-7550
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: GaAs/AlGaAs heterostructure selectively doped with Si was grown in a conventional normal pressure metalorganic chemical vapor deposition using trimethyl metals and arsine. Mobility of the two-dimensional electron gas as high as 8100, 148 000, and 401 000 cm2/V s was obtained at 300, 77, and 5 K, respectively, for a sample with an undoped Al0.3Ga0.7As spacer layer of 100 A(ring) and with a sheet electron density of about 5×1011 cm−2. The heterostructure with the spacer layer thinner than 100 A(ring) shows high mobility comparable to the best values obtained by molecular-beam epitaxy. The influence of growth parameters on the electron mobility in the heterostructure is described in detail.
    Materialart: Digitale Medien
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  • 2
    Digitale Medien
    Digitale Medien
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 58 (1985), S. 2691-2695 
    ISSN: 1089-7550
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: Optical properties were investigated on the superlattices with a unit lattice period of (AlAs)n(GaAs)n (n=1–24) which were grown by atmospheric-pressure metalorganic chemical vapor deposition. Raman spectroscopy indicated that superlattice structure is realized for each n without collapsing into alloys. Photoluminescence measurement indicated that the ultrathin-layer superlattice (with n larger than 2) has a direct energy gap, which is in good agreement with a tight-binding calculation.
    Materialart: Digitale Medien
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  • 3
    Digitale Medien
    Digitale Medien
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 59 (1986), S. 4087-4090 
    ISSN: 1089-7550
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: A new connection rule of wave functions at a heterointerface was developed. This connection rule satisfies the conservation of probability current and contains a nonparabolic effective mass of carriers as a natural consequence of the theory. The subband energies in a GaAs/AlGaAs quantum well calculated using our new connection rule are in excellent conformity with a wide range of experimental results with band discontinuity of 85% and an effective mass for hole of 0.34m0.
    Materialart: Digitale Medien
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  • 4
    ISSN: 1089-7623
    Quelle: AIP Digital Archive
    Thema: Physik , Elektrotechnik, Elektronik, Nachrichtentechnik
    Notizen: A combined machining method of diamond turning and numerically controlled elastic emission machining has been developed for finishing metal mirror surfaces made from Cu and Al alloys. A mirror surface can be polished without any stress by this method. Shape and roughness of the mirror surface examined in different machining methods are compared and discussed. A precisely shaped mirror with a roughness less than 2-nm Rmax was obtained. A copper mirror was installed in a VUV beamline of the Photon Factory. It is confirmed that the metal mirror finished by the present method has good optical characteristics for synchrotron radiation beamlines.
    Materialart: Digitale Medien
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  • 5
    Digitale Medien
    Digitale Medien
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 59 (1986), S. 2503-2506 
    ISSN: 1089-7550
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: Single quantum wells of GaAs with barriers of (AlAs)2(GaAs)2 ultrathin-layer superlattices have been fabricated and photoluminescence measurement was performed. The photoluminescence energy was found to change almost linearly against the well width and the photoluminescence linewidth to get smaller with decreasing well width, which is in marked contrast to the case of a usual alloy-barriered single quantum well. It is indicated that the effective energy gap of the ultrathin-layer superlattice barrier decreases with the decreasing well width in such a structure.
    Materialart: Digitale Medien
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  • 6
    Digitale Medien
    Digitale Medien
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 54 (1989), S. 347-349 
    ISSN: 1077-3118
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: Epitaxial Si layers with low dislocation density were grown on GaAs substrates by pyrolysis using disilane. The dislocation density evaluated from SECCO etching (HF:H2 SO4 :K2 Cr2 O7 =100 cc:50 cc:2g) was less than 104/cm2, which is lower by two orders of magnitude than that of the GaAs layer on Si substrates. We found that the electron mobility of Si layers on GaAs substrates could be raised by decreasing the growth rate and a high mobility value the same as that of a homoepitaxial layer was obtained, although the Si layers were contaminated by an arsenic impurity of 1018 cm−3 .
    Materialart: Digitale Medien
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  • 7
    ISSN: 1365-2133
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Medizin
    Notizen: Background  Although there have been several reports on the prevalence of atopic dermatitis (AD) in Japanese schoolchildren based on questionnaires, there has been no nation-wide study of the frequency of this condition diagnosed by dermatologists in regular health check-ups of schoolchildren.Objectives  The objective of this work was to evaluate precisely the prevalence of AD in elementary schoolchildren in Japan based on regular health check-ups by dermatologists.Methods  In 2001/2, elementary schoolchildren: first graders (age 6–7 years) and sixth graders (age 11–12 years) were examined by dermatologists in eight prefectures of Japan (Hokkaido, Iwate, Tokyo, Gifu, Osaka, Hiroshima, Kochi and Fukuoka). In each prefecture, public elementary schools were randomly selected from urban and rural districts. We planned to examine about 700 schoolchildren in each of urban first, urban sixth, rural first and rural sixth grades from the eight areas, a total of 22 400 children (700 × 4 × 8). AD was diagnosed by the dermatologists based on the Japanese Dermatological Association criteria for the disease.Results  The point prevalence of AD was 11·2% overall (2664 of 23 719) ranging from 7·4% (Iwate) to 15·0% (Fukuoka) in the eight areas. Seventy-four per cent, 24%, 1·6% and 0·3% of those afflicted were in the mild, moderate, severe and very severe groups, respectively. Overall, the prevalence of first graders was slightly higher than that of sixth graders (11·8% vs. 10·5%, P 〈 0·01). There was no apparent difference in prevalence between urban and rural districts, or between boys and girls.Conclusions  The prevalence of AD in Japanese elementary schoolchildren was about 10%, three-quarters of those being mildly affected. This is the first nation-wide study made of Japanese elementary schoolchildren examined by dermatologists to evaluate the frequency of AD.
    Materialart: Digitale Medien
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  • 8
    Digitale Medien
    Digitale Medien
    s.l. : American Chemical Society
    The @journal of physical chemistry 〈Washington, DC〉 79 (1975), S. 291-293 
    Quelle: ACS Legacy Archives
    Thema: Chemie und Pharmazie , Physik
    Materialart: Digitale Medien
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  • 9
    ISSN: 1365-2036
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Medizin
    Notizen: Background : The epidemiology and pathophysiology of non-erosive gastro-oesophageal reflux disease differs from erosive gastro-oesophageal reflux disease. There is a possibility that non-erosive gastro-oesophageal reflux disease treatment requires a different regimen/approach but it is not yet acknowledged.Aim : To investigate the efficacy of famotidine and omeprazole in the treatment of gastro-oesophageal reflux disease, especially non-erosive gastro-oesophageal reflux disease.Patients and methods : A randomized, open-label trial was conducted. Fifty-four gastro-oesophageal reflux disease patients were assigned to treatment with famotidine at a dosage of 20 mg twice daily; or omeprazole, 20 mg once daily, for a period of 8 weeks. The Short Form-36 Health Survey and Gastrointestinal Symptom Rating Scale administered at baseline and after 8 weeks of treatment as well as a symptom questionnaire were conducted daily.Results : Short Form-36 revealed that gastro-oesophageal reflux disease has severe impact on health-related quality of life. Thirty-nine subjects (77%) were endoscopically diagnosed as non-erosive gastro-oesophageal reflux disease. The mean Gastrointestinal Symptom Rating Scale abdominal pain, and indigestion score of non-erosive gastro-oesophageal reflux disease significantly improved in famotidine-treated patients (P 〈 0.05), but not in the omeprazole. There was no significant change regarding improved heartburn symptoms of non-erosive gastro-oesophageal reflux disease between treatments in the daytime or night-time.Conclusion : Famotidine and omeprazole were both effective in improving symptoms of gastro-oesophageal reflux disease, particularly non-erosive gastro-oesophageal reflux disease.
    Materialart: Digitale Medien
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  • 10
    Digitale Medien
    Digitale Medien
    Springer
    Marine biology 29 (1975), S. 9-13 
    ISSN: 1432-1793
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie
    Notizen: Abstract Soy cake* was homogenized and filtered through an 80 mesh net to produce small, detritus-like particles. The effect of soy-cake particles, an artificial detritus, on the survival and growth of Penaeus japonicus Bate zoea was then tested. The soy cake was considered to be effective for survival and growth of the zoea. The best survival rate, 85.9%, was obtained in a tank receiving soy cake in quantities of 0.16 mg/zoea/day. An experiment was also performed to compare three kinds of food: particles of soy cake alone, diatoms (Chaetoceros rigidus) alone, and a half and half mixture of the two. The best growth, 2.49 mm, and the highest survival rate, 79.1%, were found in larvae fed the mixture of soy-cake particles and diatoms. The results thus seem to demonstrate that particles of soy cake could be usefully applied to the mass-culture of the penaeid prawn.
    Materialart: Digitale Medien
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