Bibliothek

X
feed icon rss

Ihre E-Mail wurde erfolgreich gesendet. Bitte prüfen Sie Ihren Maileingang.

Leider ist ein Fehler beim E-Mail-Versand aufgetreten. Bitte versuchen Sie es erneut.

Vorgang fortführen?

Exportieren
  • 1
    Digitale Medien
    Digitale Medien
    A Raman study of Au/Te/Au/GaAs (100) ohmic contacts (1992)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 71 (1992), S. 739-743 
    Details
    ISSN: 1089-7550
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: Ohmic contacts produced by high-energy pulsed laser beam alloying Au/Te/Au/n-GaAs are investigated by micro Raman spectroscopy. The results are compared to those from furnace annealed ohmic contacts. For the furnace as well as for the laser annealed ohmic contacts, no evidence for a doping of the contact region is found in the Raman spectra. The presence of a highly disordered GaAs surface layer is observed for both types of contacts. In addition, after furnace processing a Ga2Te3 layer is formed. These results are consistent with earlier Mössbauer studies. For the laser alloyed samples the results strengthen the role of a defective/disordered interface structure where conduction might occur by a resonant tunneling process involving localized gap states.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.351336
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 2
    Digitale Medien
    Digitale Medien
    Epidermal growth factor receptor status in four carcinoma of the cervix cell lines (1991)
    Three Cambridge Center, Suite 208, Cambridge, MA 02142, USA : Blackwell Scientific Publications Inc.
    International journal of gynecological cancer 1 (1991), S. 0 
    Details
    ISSN: 1525-1438
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Medizin
    Notizen: We have evaluated aspects of the EGF receptor content of four human cell lines derived from patients with previously untreated carcinoma of the cervix. Scatchard analysis revealed that three of the lines possessed approximately 2×105 low-affinity and 2×104 high-affinity receptors, whereas the fourth line had approximately 9×104 low-affinity receptors and 9×103 high-affinity receptors. Immunocytochemical staining using the monoclonal antibody EGFR1 showed wide intra- and inter-line variation in staining intensity. Flow cytometric analysis of EGFR1 demonstrated a fivefold difference in staining intensity between lines. Thirteen cloned derivatives of one of the lines exhibited a 200% variation in EGFR1 staining intensity. There were no differences in radiosensitivity in four of the cloned lines with different EGF receptor levels. Southern blotting analysis did not reveal any rearrangement or amplication of the EGF receptor gene. These three different methods for determining receptor content produced variations in the ranking of receptor number across the four cell lines. These studies with cervix carcinoma cell lines demonstrate the presence of varied levels of EGF receptors according to the methodology used. This may reflect differences in biological characteristics of the cell lines evaluated.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1046/j.1525-1438.1991.01040185.x
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 3
    Digitale Medien
    Digitale Medien
    Effect of Seizures Induced by Intra-Amygdaloid Kainic Acid on Kainic Acid Binding Sites in Rat Hippocampus and Amygdala (1986)
    Oxford, UK : Blackwell Publishing Ltd
    Journal of neurochemistry 47 (1986), S. 0 
    Details
    ISSN: 1471-4159
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Medizin
    Notizen: Abstract: [3H]Kainic acid binding sites with a slow dissociation rate in the rat limbic system were investigated in detail. Extensively washed membranes prepared from the hippocampal formation and from the region comprising the amygdala and the piriform cortex yielded nonlinear Scatchard plots. Microdissection showed that the high-affinity component (affinity constant around 1 nM) was present in the hippocampal CA3 region (4.2 fmol/mg wet tissue) and the amygdaloid complex (4.6 fmol/mg wet tissue), whereas the remaining part of the hippocampal formation and the piriform lobe contained the low-affinity component (affinity constant 5–20 nM; 11.6 and 11.3 fmol/mg wet tissue, respectively). In the lateral + medial septum we detected only the low-affinity component. Severe limbic seizures, induced by unilateral injection of 0.7 or 0.8 μg kainic acid in 0.3 μl of phosphate-buffered saline into the amygdala, reduced kainic acid binding sites in the ipsilateral amygdala and CA3 region. The decline of kainic acid binding sites in the injected amygdala was followed by a similar effect in the contralateral amygdala (“mirror focus”) and later by a moderate loss also in the contralateral CA3 region. Kainic acid receptor autoradi-ography demonstrated that binding sites were lost from the stratum lucidum in hippocampus. Septal lesion had no effect on kainic acid binding sites in the hippocampus. Comparison with previous results on the histopathological changes after this lesion shows that high-affinity kainic acid binding sites are preferentially located on neurons that undergo selective degenerations after severe kainic acid-induced seizures.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1111/j.1471-4159.1986.tb00671.x
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 4
    Digitale Medien
    Digitale Medien
    Depth inhomogeneity of porous silicon layers (1996)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 80 (1996), S. 2990-2993 
    Details
    ISSN: 1089-7550
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: The two possible causes of depth inhomogeneities of the microstructure of porous silicon are changes in the HF concentration with depth and a varying chemical etching rate of the porous silicon layer. During anodization chemical etching will become important for microporous silicon — e.g. p-porous silicon — due to the large internal surface area, especially at long etching times. On the other hand, a considerable decrease of the HF concentration will occur during etching with high current densities to produce p+-porous silicon with high porosities. We have investigated the depth inhomogeneity of porous silicon layers by spectroscopic ellipsometry, Raman spectroscopy and photoluminescence measurements. From a line shape analysis of the Raman signal a size distribution of nanocrystals is deduced. For p-porous silicon smaller nanocrystals are found near the surface of the layer; for p+-porous silicon etched with high current densities smaller nanocrystals are found near the porous silicon/substrate interface. © 1996 American Institute of Physics.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.363156
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 5
    Digitale Medien
    Digitale Medien
    Effect of high-temperature anneal on interface states generation in stressed metal-oxide-semiconductor devices (1991)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 58 (1991), S. 598-600 
    Details
    ISSN: 1077-3118
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: Polycrystalline silicon gate metal-oxide-semiconductor transistors, fabricated with polycrystalline silicon leads, were repeatedly electrically stressed by constant-current Fowler–Nordheim tunneling cycles. After every stress cycle the devices were annealed for various time intervals at 950 °C. Capacitance-voltage measurements were used to detect stress-related interface-state generation rates and saturation values. It was found that although the stress-generated interface states are totally annealed by the thermal treatment, their generation rates and saturation values after anneal are a strong function of the anneal time, significantly exceeding the values of the fresh devices and inversely dependent on the anneal time. From the results it is concluded that a new type of latent interface-state sites is generated by the combination of tunneling stress and high-temperature annealing.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.104598
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 6
    Digitale Medien
    Digitale Medien
    The orientation of the magnetization of thin films as determined by the Hall effect (1987)
    [S.l.] : American Institute of Physics (AIP)
    Journal of Applied Physics 61 (1987), S. 3816-3818 
    Details
    ISSN: 1089-7550
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: The Hall effect is a useful probe of the magnetization in thin metallic films since the signal is inversely proportional to the film thickness. Previously, the minimum in the coercivity, derived from the Hall hysteresis loop as a function of the angle of the applied field, has been used to determine the hard axis of magnetic thin films. A vibrating sample magnetometer can be used in this fashion if coherent rotation is the magnetization reversal mechanism. However, we show that even in the case of the Stoner–Wohlfarth model, the minimum of the Hall coercivity does not coincide with the hard axis. We propose an alternative method for determining the easy axis, which is independent of the magnetization reversal mechanism and does not require measuring the entire hysteresis loop. In addition, since for an arbitrary orientation of the applied field the measured Hall voltage will contain components due to magnetoresistance as well as the Hall effect, it is possible to extract a measure of the in-plane and perpendicular magnetization. Using this information, we derive a method of producing vector plots that show the magnitude and direction of the magnetization as a function of applied field for various applied-field orientations. Examples using CoCr and TbFe will be presented.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.338606
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 7
    Digitale Medien
    Digitale Medien
    Shortened REM Latency: Consequence of Psychological Strain? (1987)
    Oxford, UK : Blackwell Publishing Ltd
    Psychophysiology 24 (1987), S. 0 
    Details
    ISSN: 1469-8986
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Medizin , Psychologie
    Notizen: Previous research has demonstrated that in healthy subjects sit uat ional strain may provoke not only sleep disturbances characteristic of depression (e.g., shortened REM latencies), but also alterations in dream content. Nevertheless, there are some controversial results. The aim or our study was to clarify these inconsistencies by developing a design which might avoid some methodological problems which were present in some of these previous studies. Eleven male subjects slept in the laboratory for 7 consecutive nights. During 1 evenings they saw a stressful and a neutral movie in randomized order. The subsequent nights included REM sleep awakenings for the purpose of dream collections. Whereas the subjects were demonstrably affected by the disturbing films, the patterns of subsequent sleep remained unchanged. In contrast manifest content of the initial dreams were clearly altered. Whereas the modes of dreaming were quite different within post-stress nights, mood was unproved the next morning in all subjects. The results are discussed within the framework of several prevailing concepts about sleep, dreams, and psychological strain.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1111/j.1469-8986.1987.tb00293.x
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 8
    Digitale Medien
    Digitale Medien
    Generation and anneal of a new kind of interface state in stressed and high-temperature annealed metal-oxide-semiconductor devices (1992)
    Woodbury, NY : American Institute of Physics (AIP)
    Applied Physics Letters 60 (1992), S. 186-188 
    Details
    ISSN: 1077-3118
    Quelle: AIP Digital Archive
    Thema: Physik
    Notizen: Polycrystalline silicon (poly) gate metal-oxide-semiconductor (MOS) transistors were electrically stressed by constant-current tunneling. After the stress the devices were thermally annealed for variable times in the temperature range between 800 and 950 °C, and a second tunneling stress was performed. Capacitance-voltage (C-V) curve broadening and a charge pumping (CP) technique were used to detect interface state generation. It was found that the stress generated interface states are totally annealed by the thermal treatment. On the other hand, generation rates and saturation values, due to the second stress after annealing, exceed those of the fresh devices. Analysis of the generation process indicates that two types of interface states are generated: one, similar in its generation rate and saturation value to that of a fresh device, and another one, which is characterized by a higher generation rate and saturation value, is attributed to a new type of latent site. The density of this new type of latent interface states site decays exponentially with the annealing time. The annealing rate follows a temperature-dependent Arrhenius function. The anneal of this new type of interface state is characterized by an activation energy of 3.47 eV.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.106958
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 9
    Digitale Medien
    Digitale Medien
    Thymidine Hydroperoxides: Structural Assignment, Conformational Features, and Thermal Decomposition in Water (1994)
    s.l. : American Chemical Society
    Journal of the American Chemical Society 116 (1994), S. 2235-2242 
    Details
    ISSN: 1520-5126
    Quelle: ACS Legacy Archives
    Thema: Chemie und Pharmazie
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1021/ja00085a001
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 10
    Digitale Medien
    Digitale Medien
    A comparative study of formaldehyde detection using chromotropic acid, acetylacetone and HPLC in cosmetics and household cleaning products (1992)
    Oxford, UK : Blackwell Publishing Ltd
    Contact dermatitis 26 (1992), S. 0 
    Details
    ISSN: 1600-0536
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Medizin
    Notizen: Chromotropic acid and acerylacetone methods for qualitative determination of formaldehyde were tested in parallel on 4N commercial samples, with high-performance liquid chromotography (HPLC) implemented for quantitave measuce. In addition, interference with the detection of formaldehyde was investigated by analyzing 12 other aldehydes and ketories, 7 essential oils and 3 polysorbstes. Throughout this comparative-study. the disadvantages of the chromotropic acid method., of with 2 variants were used, were delineated and we found that the acetylacetone test proved to be a more efficient screening method for formaldehyde detection in a clinical laboratory.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1111/j.1600-0536.1992.tb00284.x
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
Schließen ⊗
Diese Webseite nutzt Cookies und das Analyse-Tool Matomo. Weitere Informationen finden Sie hier...