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
Filter
  • 2000-2004  (2)
  • 1990-1994  (3)
Datenquelle
Materialart
Erscheinungszeitraum
Jahr
Schlagwörter
  • 1
    Digitale Medien
    Digitale Medien
    The microwave rotational spectrum of the Ar–CO dimer (1993)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 98 (1993), S. 9399-9404 
    Details
    ISSN: 1089-7690
    Quelle: AIP Digital Archive
    Thema: Physik , Chemie und Pharmazie
    Notizen: Pure rotational spectra of four different isotopomers of the dimer Ar–CO have been investigated between 8 and 18 GHz using a pulsed beam cavity Fourier transform spectrometer. The spectra confirm that the complex is a prolate near-symmetric rotor with an essentially T-shaped structure, and that it undergoes large amplitude zero-point motion. It is shown that on the average the argon is closer to the oxygen than to the carbon. The transitions measured obey a-type selection rules with ΔJ=+1, ΔKa=0, and ΔKc=+1. For 40Ar–12C16O, transitions have been observed for Ka=0 and 1 with lower state J values of 1, 2, and 3. For 40Ar–13C16O and 40Ar–13C18O, a similar series was measured, but only for Ka=0. For 40Ar–13C17O, the 17O quadrupole hyperfine pattern was resolved in the rotational transition JKaKc = 202–101. Determinations have been made for rotational and centrifugal distortion constants, as well as for the 17O quadrupole coupling constant χaa. Effective values have been obtained for the length of the line from the center of mass of the CO subunit to the argon nucleus, and for the angle between this line and the CO bond.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1063/1.464371
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 2
    Digitale Medien
    Digitale Medien
    High-cycle fatigue properties in Ti–5% Al–2.5% Sn ELI alloy with large grain size at cryogenic temperatures (2004)
    PO Box 1354, 9600 Garsington Road, Oxford OX4 2XG, UK. : Blackwell Science Ltd
    Fatigue & fracture of engineering materials & structures 27 (2004), S. 0 
    Details
    ISSN: 1460-2695
    Quelle: Blackwell Publishing Journal Backfiles 1879-2005
    Thema: Maschinenbau
    Notizen: High-cycle fatigue properties were investigated for Ti–5% Al–2.5% Sn ELI alloy with a mean α grain size of 80 μm, which had been used for liquid hydrogen turbo-pumps of Japanese-built launch vehicles. At cryogenic temperatures, the fatigue strength in high-cycle region did not increase in proportion to increments of the ultimate tensile strength and the fatigue strengths at around 106 cycles were about 300 MPa independent of test temperatures. Fatigue cracks initiated in the specimen interior independent of the test temperatures of 4 K, 77 K and 293 K. At 4 K and 77 K, several crystallographic facet-like structures were formed at crack initiation sites. On the other hand, there were no facet-like structures that could be clearly identified at the crack initiation sites at 293 K. Low fatigue strengths in longer-life region at cryogenic temperatures could be attributable to the formation of large sub-surface crack initiation sites, where large facet-like structure are formed.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1111/j.1460-2695.2004.00742.x
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 3
    Digitale Medien
    Digitale Medien
    Effects of vitamin A on proliferation of human distal airway epithelial cells in culture (1994)
    Springer
    Virchows Archiv 424 (1994), S. 525-531 
    Details
    ISSN: 1432-2307
    Schlagwort(e): Human lung ; Bronchiolar epithelium Growth inhibition ; Growth enhancement ; Vitamin A
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Abstract Using a serum-free culture method, we investigated the effects of vitamin A on the proliferation of human distal airway epithelial cells. Outgrowth of epithelial cells from lung tissue explants was enhanced by treatment with all-trans retinol at concentrations of 10−8 to 10−7 M. The colony-forming activity of cells harvested from the primary culture and replated onto Swiss 3T3 fibroblastic feeders was, in contrast, significantly reduced by 10−7 M to 10−5 M retinol. When the primary cells were harvested and subcultured on Primaria plates, population expansion was also inhibited by retinol at 10−10 to 10−6 M. We further investigated the cells to determine whether there was any difference in sensitivity to the growth-inhibitory effects of vitamin A between cells from the primary culture incubated with and without retinol. The population increase in cells harvested from the primary culture was inhibited equally in retinol-treated and non-treated cells by subsequent treatment with retinol or retinoic acid, this inhibition being dose-dependent. DNA synthetic activity was also inhibited. Interestingly, both the growth rate and the colony-forming efficiency on feeders were greater in the subculture of cells from the retinol-treated primary culture than in those non-treated. When the cells in the secondary subculture were treated with retinoic acid and replated again, they showed a greater population increase rate than those non-treated. Our results showed that human distal airway epithelial cells isolated from lung tissue were sensitive to the growth-inhibitory effect of vitamin A, but the proliferative potential in some fraction of the epithelial cell population was possibly enhanced by vitamin A treatment.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00191439
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 4
    Digitale Medien
    Digitale Medien
    Central nervous system changes in mitochondrial encephalomyopathy: light and electron microscopic study (1992)
    Springer
    Acta neuropathologica 83 (1992), S. 449-452 
    Details
    ISSN: 1432-0533
    Schlagwort(e): Mitochondrial encephalomyopathy ; MELAS ; Neuropathology
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Medizin
    Notizen: Summary An autopsy case of mitochondrial encephalomyopathy with lactic acidosis and stroke-like episodes (MELAS) is reported. It presented with generalized muscle atrophy, stroke-like episodes, schizophrenia-like mental disorder and progressive dementia. Serum lactate and pyruvate levels were high. In the biopsied muscles, ragged-red fibers were observed by light microscopy and aggregation of abnormal mitochondria with paracrystaline formation by electron microscopy. The most characteristic neuropathological findings were infarct-like lesions widespread in the cerebral cortex. In addition, this case showed some unusual pathological features: (1) diffuse moderate fibrillary gliosis in the whole cerebral and cerebellar white matter, which might have been due to metabolic disturbances; (2) several focal lesions with demyelination and numerous spheroids in the pontocerebellar fibers; and (3) marked degeneration of the posterior columns and spinocerebellar tracts. Electron microscopic examination revealed that abnormal mitochondria were markedly aggregated in smooth muscle cells and endothelium of the cerebral and cerebellar blood vessels. These fine structural findings suggest a “mitochondrial angiopathy”.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/BF00713541
    Bibliothek Standort Signatur Band/Heft/Jahr Verfügbarkeit
    BibTip Andere fanden auch interessant ...
    Artikel (Nationallizenzen)
    Volltext
  • 5
    Digitale Medien
    Digitale Medien
    Del(X)(p21.1) in a mother and two daughters: genotype-phenotype correlation of Turner features (2000)
    Springer
    Human genetics 〈Berlin〉 106 (2000), S. 306-310 
    Details
    ISSN: 1432-1203
    Quelle: Springer Online Journal Archives 1860-2000
    Thema: Biologie , Medizin
    Notizen: Abstract. We report a mother and two daughters with partial Xp monosomy. Clinical assessment for Turner phenotype revealed that the three females manifested low-normal to mild short stature (–1.6 to approximately –2.3 SD) and variable degrees of skeletal features, such as cubitus valgus, short 4th matacarpals, and Madelung deformity, but no soft tissue or visceral anomalies or gonadal dysfunction. Cytogenetic studies for lymphocytes showed that the karyotype was 45,X[3]/46,X,del(X)(p21.1)[27] in the mother and non-mosaic 46,X,del(X)(p21.1) in the two daughters. Fluorescence in situ hybridization and microsatellite analyses for 19 loci/regions on the X chromosome demonstrated that the del(Xp) chromosome was missing SHOX and had the breakpoint between DMD and CYBB. The results are consistent with the recently proposed notion that haploinsufficiency of SHOX results in not only short stature, but also Turner skeletal features in association with maturational effects of gonadal estrogens. The lack of soft tissue or visceral anomalies suggests the presence of the putative lymphogenic gene on the del(Xp) chromosome; the preservation of ovarian function appears to be compatible with meiotic pairing failure being relatively mild.
    Materialart: Digitale Medien
    URL: http://dx.doi.org/10.1007/s004390000253
    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...