1,726,219 research outputs found
Evang. Armen-Fürsorge Grombühl-Würzburg
No full textEVANG. ARMEN-FÜRSORGE GROMBÜHL-WÜRZBURG
Evang. Armen-Fürsorge Grombühl-Würzburg ( -
Utvidet eller opprinnelig helsebegrep?
No full textDe som idag angriper medicinen för ett individualistiskt, sjukdomskoncentrerat och biologiskt-fysiskt orienterat hälsobegrepp är inte helt ajour. De undervärderar de förändringar som sker i riktning mot ett socialmedicinskt orienterat och mer realistiskt hälsobegrepp och som redan gett klara utslag också i hälsovårdens struktur och funktioner. Detta framhåller dr Karl Evang i en historisk analys av hälso- och sjukdomsbegreppens utveckling de senaste 100 åren.Karl Evang har varit Norges helsedirektör från 1939 till 1973
Serie Frakenthal // Evang. Kirche
No full textSERIE FRAKENTHAL // EVANG. KIRCHE
Serie Frakenthal // Evang. Kirche ( -
Bad Godesberg, Evang. Pädagogium
No full textBAD GODESBERG, EVANG. PÄDAGOGIUM
Bad Godesberg, Evang. Pädagogium ( -
Absence of Partial Amorphization in GeSbTe Chalcogenide Superlattices
Full text linkPhase-change materials (PCMs) are widely used for optical data storage due to their fast and reversible transitions between a crystalline and an amorphous phase that exhibit reflectivity contrast. In the last decade, PCMs have been found to be promising candidates for the development of nonvolatile electronic memories, as well. In this context, superlattices of thin layers of GeTe and Sb2Te3 show an unprecedented performance gain in terms of switching speed and power consumption with respect to bulk GeSbTe compounds. Models of crystalline–crystalline transitions, proposed to explain the improved properties, however, are challenged by recent experiments in which GeTe–Sb2Te3 superlattices are observed to reconfigure toward a van der Waals heterostructure of rhombohedral GeSbTe and Sb2Te3. Herein, ab initio molecular dynamics simulations are used to explore an alternative switching mechanism that comprises amorphous–crystalline transitions of ultrathin GeSbTe layers between crystalline Sb2Te3. Despite some positive results obtained by tailoring the quenching protocol, overall the extensive simulations do not yield clear evidence for this mechanism. Therefore, they suggest that the switching process probably involves a transition between two crystalline states
Serie Arco. Evang. Kirche, 5
No full textSERIE ARCO. EVANG. KIRCHE, 5
Serie Arco. Evang. Kirche, 5 ( -
Evang. Burgkirche zu Herleshausen/Werra
No full textEVANG. BURGKIRCHE ZU HERLESHAUSEN/WERRA
Evang. Burgkirche zu Herleshausen/Werra ( -
3501 Evang. Stadtkirche zu Zierenberg
No full text3501 EVANG. STADTKIRCHE ZU ZIERENBERG
3501 Evang. Stadtkirche zu Zierenberg ( -
Point defects in disordered and stable GeSbTe phase-change materials
No full textPhase-change materials (PCMs) are promising candidates for efficient storage-class memory exploiting the pronounced resistivity contrast between their amorphous and crystalline phase. GeSbTe compounds, the prototypical class of PCMs, are theoretically predicted to be small-gap semiconductors in their disordered, cubic and ordered, hexagonal phase, but in experiment they show p-type conduction. While this is attributed to self-doping, the very defect types responsible have not been entirely identified. Here, we present an ab-initio study of point defects and their formation energies in GeSb2Te4 and Ge2Sb2Te5 in their disordered and ordered crystalline phases. Our simulations indicate that GeSb, rather than VGe or SbTe, is the most important defect to explain p-doping in the hexagonal structure. In the disordered phase, on the other hand, standard gradient-corrected functionals yield low-formation energies for defects associated with n-type conduction, in apparent contradiction with experimental data. We discuss possible sources for this discrepancy and argue that it stems from the underestimation of the band gap
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