198,803 research outputs found
Dissertatio iuridica de condemnatione absentium
No full textquam ... pro summis in utroque iure honoribus rite consequendis publico eruditorum examini submittit Leonardus Fridericus Voit a Berg Augusta Vindelicus, die ... Iunii, an. M. DC. XCIII.Enthält 5 Cap.Datum hs. ergänzt: fir 16 IuniiDiss. iur. Basel, 169
Gas entropy in a representative sample of nearby X-ray galaxy clusters (REXCESS): relationship to gas mass fraction
No full textWe examine the radial entropy distribution and its scaling using 31 nearby galaxy clusters from the representative XMM-Newton cluster structure survey (REXCESS), a sample in the temperature range 2-9 keV selected in X-ray luminosity only, with no bias toward any particular morphological type. The entropy profiles are robustly measured at least out to R1000 in all systems and out to R500 in thirteen systems. Compared to theoretical expectations from non-radiative cosmological simulations, the observed distributions show a radial and mass-dependent excess entropy, such that the excess is greater and extends to larger radii in lower mass systems. At R500, the mass dependence and entropy excess are both negligible within the large observational and theoretical uncertainties. Mirroring this behaviour, the scaling of gas entropy is shallower than self-similar in the inner regions, but steepens with radius, becoming consistent with self-similar at R500. There is a large dispersion in scaled entropy in the inner regions, apparently linked to the presence of cool cores and dynamical activity; at larger radii the dispersion decreases by approximately a factor of two to 30 per cent, and the dichotomy between subsamples disappears. There are two peaks in the distribution of both inner slope and, after parameterising the profiles with a power law plus constant model, in central entropy K0. However, we are unable to distinguish between a bimodal or a left-skewed distribution of K0 with the present data. The distribution of outer slopes is unimodal with a median value of 0.98, and there is a clear correlation of outer slope with temperature. Renormalising the dimensionless entropy profiles by the gas mass fraction profile fgas (<R), leads to a remarkable reduction in the scatter, implying that gas mass fraction variations with radius and mass are the cause of the observed entropy structural and scaling properties. The results are consistent with the picture of a cluster population in which entropy modification is centrally concentrated and extends to larger radii at lower mass, leading to both a radial and a mass-dependence in the gas mass fraction, but which is increasingly self-similar at large radius. The observed normalisation, however, would suggest entropy modification at least up to R1000, and even beyond, in all but the most massive systems. We discuss a tentative scenario to explain the observed behaviour of the entropy and gas mass fraction in the REXCESS sample, in which a combination of extra heating and merger mixing maintains an elevated central entropy level in the majority of the population, and a smaller fraction of systems is able to develop a cool core. <br/
... Periēgēsis de contagionis essentia: speciatim de Peste, eius causis, praecautione & Cura
No full textPro Docturae Medicae insignib. & privilegiis Placidae bonorum in congressu publico disquisitioni subiicit Nathan Voitus Servestensis Anhaltinus. Ad d. April. 2. Anni M D C IVEnth. 137 ThesenDiss. med. Basel, 160
Evidence for X-ray emission from a large-scale filament of galaxies?
No full textCosmological simulations predict that a large fraction of the baryonic mass of the universe exists as 10(5)-10(7) K diffuse, X-ray-emitting gas, tracing low-density filament and sheetlike structures exterior to massive clusters of galaxies. If present, this gas helps reconcile the current shortfall in observed baryon counts relative to the predictions of the standard big bang model. We present here the discovery and analysis of a 5 sigma significance half-degree filamentary structure, which is present in both the I-band salary surface density and the unresolved X-ray emission in a deep ROSAT PSPC field. The estimated diffuse X-ray emission component of this structure has a surface brightness of similar or equal to 1.6 x 10(-16) ergs s(-1) cm(-2) arcmin(-2) (0.5-2 keV), comparable to the predictions for intercluster gas, and may represent a direct detection of this currently unconfirmed baryonic component
Hyperstar poly(ester-methacrylate)s as additives in thermally and photocured epoxy resins
No full textDr. Ludwig Voit und Dr. Hans Bengl, Römisches Erbe. Ein Lesebuch lateinischer Literatur. 1951
No full textJ. M. Dr. Ludwig Voit und Dr. Hans Bengl, Römisches Erbe. Ein Lesebuch lateinischer Literatur. 1951. In: Bulletin de l'Association Guillaume Budé,n°1, mars 1952. p. 101
Dr. Ludwig Voit und Dr. Hans Bengl, Römisches Erbe. Ein Lesebuch lateinischer Literatur. 1951
No full textJ. M. Dr. Ludwig Voit und Dr. Hans Bengl, Römisches Erbe. Ein Lesebuch lateinischer Literatur. 1951. In: Bulletin de l'Association Guillaume Budé,n°1, mars 1952. p. 101
Scratch resistant tough nanocomposite epoxy coatings based on hyperbranched polyesters
No full textAdvanced multifunctional coatings were prepared by UV curing of epoxy based formulations containing hyperbranched polymers (HBP) and an epoxy functionalized alkoxysilane additive. The addition of HBP to the UV curable epoxy resin induced an important flexibilization of the glassy epoxy network with an increase in toughness of the cured polymeric coatings. Adding the functionalized alkoxysilane into the UV curable formulations, as inorganic precursor of silica phase, an improvement on surface hardness was obtained without strongly affecting the flexibilization and the toughness achieved by the addition of the HBP additive. The increase on surface hardness was accompanied with an increase in scratch resistance and modulus. Advanced scratch resistant and tough nanocomposite epoxy coatings were obtained by properly selecting the components of the formulation
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