Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Dynamical Hopf bifurcation in piezoelectric semiconductor resonators (1989)
    Springer
    Applied physics 48 (1989), S. 177-180 
    Details
    ISSN: 1432-0630
    Keywords: 72.20H ; 43.25 ; 72.80E
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics , Physics
    Notes: Abstract Time-dependent Hopf bifurcations in the current-voltage characteristics of piezoelectric semiconductor resonators were investigated experimentally. The switching transition between acoustic bistable states was observed under a quasi-static variation of applied voltage. The peculiar pulse responses of the resonant currents were observed when the rise-time of the pulses exceeded the eigen-period of the system. The existence of a metastable state in the dynamical Hopf bifurcation are discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01141281
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Out-diffusion of Ga and As atoms into dielectric films in SiOx /GaAs and SiNy/GaAs systems (1989)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 66 (1989), S. 5809-5815 
    Details
    ISSN: 1089-7550
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Residual Ga and As atoms in SiOx and SiNy dielectric films deposited on GaAs were investigated by Rutherford backscattering spectroscopy and particle-induced x-ray emission techniques. Both Ga and As atoms were detected in the films after high temperature heat treatment, and even in the films as-deposited. The magnitude of the residual atoms presumably out-diffused from GaAs substrates was of the order of 1×1019 /cm3. The concentration of Ga atoms prevails over that of As atoms in SiOx/GaAs systems as is generally known, and vice versa in SiNy/GaAs systems after heat treatment. Dynamic behavior of Ga and As atoms in the films as functions of annealing temperature and annealing time cannot be explained by a simple diffusion mechanism. A model is proposed that the damaged layer around the interface of the systems is responsible for the anomalous out-diffusion phenomena.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.343651
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Two-photon processes in defect formation by excimer lasers in synthetic silica glass (1988)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 53 (1988), S. 1891-1893 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: Defect formation in dehydrated silica glasses was investigated using various excimer lasers with different energies. The ArF laser (6.4 eV) generates the E' center more effectively than the KrF laser (5.0 eV), while the XeCl laser (4.0 eV) generated no centers. Defect generation was found to be proportional to the square of the laser photon density, indicating that it occurs dominantly due to a two-photon process which makes band-to-band excitation possible. The E' center probably originated from oxygen-deficient centers. Contributions to the E' center formation from a process involving direct absorption at the sites of intrinsic defects in SiO2 glass were discussed on the basis of the excitation energy dependence and a comparison with the effect of a low-pressure mercury lamp.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.100362
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Specific lattice location of Zn in CdTe determined by ion-channeling methods (1988)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 52 (1988), S. 200-202 
    Details
    ISSN: 1077-3118
    Source: AIP Digital Archive
    Topics: Physics
    Notes: The specific lattice location of Zn in CdTe single crystals has been investigated by ion-channeling methods combined with particle-induced x-ray emission. Observing the asymmetry effects of channeling dips around the [110] axis and analyzing the asymmetry factors for host atoms and doped Zn atoms, it is revealed that almost all Zn atoms occupy the Cd sublattice sites, and Zn-doped CdTe crystals grown by vertical Bridgman methods appear to be almost completely free from the segregation of doped Zn atoms.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.99653
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Germination of cocklebur seed and growth of their axial and cotyledonary tissues in response to C2H4, CO2 and/or O2 under water stress (1989)
    Oxford, UK : Blackwell Publishing Ltd
    Plant, cell & environment 12 (1989), S. 0 
    Details
    ISSN: 1365-3040
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: Abstract. Germination modes of lower seeds of cocklebur (Xanthium pennsylvanicum Wallr.) under different water stresses, prepared with mannitol solution, were examined in relation to gaseous factors. As the concentration of mannitol increased, germination was increasingly inhibited at a mode which was drawn by two straight lines having different slopes and meeting at an angle. One is a sharp line occurring at the lower concentrations of mannitol; the other is a gentle line occurring at higher concentrations of mannitol. The former reflected the growth response of axial tissues to mild water stress, whereas the latter reflected the growth response of cotyledonary tissues to severe water stress. The germination potential of cocklebur seeds increased with increasing temperature. Thus, the seeds were more resistant to water stress at higher than al lower temperatures. This increased germination potential under water stress resulted from the greater growth potential of axial tissues, but not cotyledonary tissues, at higher temperature. Increased O2 levels improved both the reduced axial and cotyledonary growth under water stress. Carbon dioxide predominantly enhanced axial growth under water stress, whereas C2H4 exclusively enhanced cotyledonary growth. Thus, these gases were effective in potentiating germination under water stress. When combined with each other, these gases caused more pronounced growth of the axial and cotyledonary tissues, leading to germination under more severe water stresses. Maximal axial and cotyledonary growth under water stress occurred in the simultaneous presence of CO2, C2H4 and O2, which allowed the germination at higher mannitol concentrations above 0.6 kmol m−3 From these results, it was suggested that cocklebur seeds would override water stress by depending upon both the Corresponding axial growth and the C2H4-responding cotyledonary growth.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1365-3040.1989.tb01931.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Effect of crystallization temperature and additives on the orientation degree of calcium phosphate glass-ceramics prepared by unidirectional crystallization (1987)
    Springer
    Journal of materials science 6 (1987), S. 394-396 
    Details
    ISSN: 1573-4811
    Source: Springer Online Journal Archives 1860-2000
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01756774
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Haemodynamics and oxygen metabolism in patients after reversible ischaemic attack or minor ischaemic stroke assessed with positron emission tomography (1987)
    Springer
    Neuroradiology 29 (1987), S. 416-421 
    Details
    ISSN: 1432-1920
    Keywords: Reversible ischaemic attacks ; Positron tomography ; Cerebral blood flow ; Cerebral blood volume ; Cerebral oxygen metabolism ; Carotid stenosis
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary Regional cerebral blood flow (CBF), blood volume (CBV) and oxygen metabolic rate (CMRO2) were evaluated and compared among normals, patients with recent reversible ischaemic attacks (RIAs) and patients with chronic minor infarction using positron emission tomography. Average CBF together with CMRO2 significantly decreased in the infarction group in the middle cerebral artery territory of the affected hemisphere while the mean values for RIAs were intermediate between the other two groups. CBV also reduced, however it was more preserved compared to flow as seen in decreased CBF/CBV values. Significant interhemispheric difference was found in CBF/CBV ratio, but it did not clearly correlate with OEF changes. Higher OEF was noted only in the restricted brain regions of RIAs where CBF showed large hemispheric asymmetry. However, in other regions, the coupled decline of blood flow and metabolism was found which suggests tissue damage or neuronal cell loss in the brain with previous RIA symptoms.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00341736
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Positron CT imaging of an impending stroke (1988)
    Springer
    Neuroradiology 30 (1988), S. 276-279 
    Details
    ISSN: 1432-1920
    Keywords: Transient ischemic attack ; Cerebral infarction ; Cerebral blood flow ; Positron tomography
    Source: Springer Online Journal Archives 1860-2000
    Topics: Medicine
    Notes: Summary We present PET findings of a case of a transient ischemic attack which later progressed to cerebral infarction. Cerebral blood flow at the stroke focus in the right parietal cortex measured after a TIA attack and before stroke was as low as 24 ml/100 g/min with some increase in oxygen extraction fraction and blood volume. The condition was compatible with “misery perfusion”. This case may be an example suggestive that the “misery perfusion sign” is a warning of impending stroke and its poor prognosis if left without appropriate treatments.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00341844
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Asymptotically adapted three-body molecular states (1987)
    Springer
    Few body systems 2 (1987), S. 127-143 
    Details
    ISSN: 1432-5411
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract For the first time a formal theory for three-body rearrangement scattering processes in the molecular-state approach is formulated removing difficulties with unphysical long-range couplings.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01080836
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Determination of dispersive and nondispersive components of the surface free energy of glass fibers (1989)
    Springer
    Colloid & polymer science 267 (1989), S. 637-642 
    Details
    ISSN: 1435-1536
    Keywords: Surfacefreeenergy ; glassfiber ; tensiometry ; contact angle
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology , Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Abstract The dispersive component γ s d of the surface free energy of glass fibers and its interaction energy with alkanes, benzene, 1-nitropropane, ethyleneglycol, glycerol, formamide, and water were quantitatively determined by the tensiometric method within two liquids. The values of nondispersive interaction energy I SL p were found to be a linear function of the square root of the nondispersive component of the surface free energy of liquids. This suggests that the nondispersive interaction energy may be represented by the geometric mean of the nondispersive component of the surface free energy of a solid and a liquid. The slope gave the nondispersive component γ s p of the surface free energy. The γ s p values are 33 and 14 mJ/m2 for the untreated and aminosilane-treated fibers, respectively, suggesting that organophilic character has developed on the surface after aminosilane treatment. The γ s p value was almost similar after the treatment, probably because of the polar characteristics of amino groups.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01410441
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...