Search results for "density [astrophysics]"

Funzionamento del codice retorico e contenuti ideologici propri dell’autore: Libanio

2006

Through the internal analysis of Libanius of Antioch's Orations 46, 56 and 57, the work attempted to distinguish between the application and functioning of the rhetorical code and the author's own content, between rhetorical devices and ideological assumptions. The study of the density of rhetorical figures is the method of analysis used to verify the objectivity of the speaker's parrhesia

Small-angle x-ray scattering experiments for investigating the validity of the two-phase model

1973

A New method for evaluating SAXS curves of polymer samples with lamellar structure is applied to two typical scattering curves measured with a solution-crystallized linear polyethylene and a melt-crystallized branched polyethylene respectively. The method permits a rigorous check of the validity of the two-phase model and yields, without additional measurement, the volume fractions of the two phases and the difference in their densities. The densities can than be obtained by measuring the overall density of the sample. The results are: ρc = 0.996 g/cm3,ρa = 0.854 g/cm3, wa = 0.20 for the solution-crystallized sample; ρc = 0.967 g/cm3,ρa = 0.850 g/cm3, wa = 0.36 for the melt-crystallized sam…

Disorder-induced gap in the normal density of states of the organic superconductorκ-(BEDT-TTF)2Cu[N(CN)2]Br

2015

The local density of states (DOS) of the organic superconductor κ-(BEDT-TTF)2Cu[N(CN)2]Br, measured by scanning tunneling spectroscopy on in situ cleaved surfaces, reveals a logarithmic suppression near the Fermi edge persisting above the critical temperature T(c). The experimentally observed suppression of the DOS is in excellent agreement with a soft Hubbard gap as predicted by the Anderson-Hubbard model for systems with disorder. The electronic disorder also explains the diminished coherence peaks of the quasi-particle DOS below T(c).

Manipulating and squeezing the photon local density of states with plasmonic nanoparticle networks

2010

International audience; In this Brief Report, we show that when interconnected networks of gold particles are deposited onto a clean planar surface, they strongly modify the photonic local density of states LDOS in the immediate proximity of the self-assembled nanoparticles. They represent unique architectures for the subwavelength patterning of initially flat photonic LDOS. Moreover, we show that their local spectral signatures are well suited for the generation of sites able to enhance molecular fluorescence intensity.

Optical addressing at the subwavelength scale

2000

The Green dyadic formalism is applied to the study of the optical properties of dielectric subwavelength structures integrated in coplanar geometry. We first consider homogeneous wires with high refractive index featuring subwavelength cross sections. We show that such wires may have guiding properties and that they may be coupled with a local illumination produced by a focused Gaussian beam totally reflected at the substrate interface. When excited by the focused beam, these subwavelength optical waveguides (SOW's) provide a confined source of light that could be used to excite a single nanoscopic object. Well designed heteregeneous wires resulting from the alignment of dielectric particle…

The antioxidant effect in controlling thermal degradation of a LDPE blow film

2004

It is well known that antioxidants are widely used to prevent thermal degradation of high density and linear low density polyethylene. Antioxidants are not always present in low density polyethylene and only small amounts are usually added to these resins. In this work the effect of an antioxidant system on a low density resin having MFI (190 °C/2.16 kg)=2 g/10′ and density 0.9230 g/cm3 has been studied. Its effect on melt viscosity has been studied by means of a batch mixer and the torque vs time behaviour has been analysed. The results show that a maximum in the torque vs time curve can be seen for the material containing antioxidant. In contrast, the material without antioxidant does not…

The rheological behaviour of HDPE/LDPE blends. II. Die swell and normal stresses

1984

Die swell data are presented for different high-density/low-density polyethylene blends. The data relating to samples with frozen-in stresses are represented, collected as a function of the usual operational parameters (L/D ratio, flow rate, temperature). Data obtained with annealed samples are used to derive, through a theoretical approach, normal stresses. Die Strahlaufweitung wurde fur verschiedene Mischungen aus Polyethylenen hoher und niedriger Dichte gemessen. Die an Proben mit eingefrorenen Spannungen erhaltenen Werte wurden in Abhangigkeit von technologischen Parametern (Lange/Durchmesser-Verhaltnis, Fliesgeschwindigkeit, Temperatur) dargestellt. An getemperten Proben gemessene Wert…

Mechanical properties of blends of low density polyethylene with isotactic polypropylene II. effect of mixing temperature and rate

1989

Abstract The effects of mixing temperature and rate on tensile properties of some blends of low density polyethylene with isotactic polypropylene have been studied. Results, with those presented previously on the effect of mixing time, indicate significant effects of mixing parameters and suggest the need to find an “optimum mixing procedure” for each kind of blend.

The rheological behaviour of HDPE/LDPE blends

1983

The rheological behaviour of three types of HDPE/LDPE blends at several compositions (various weight percentages of LDPE) has been studied with the aid of a capillary rheometer and three different capillaries.

1997

Polyethylene wastes (low-density polyethylene, high-density polyethylene and their binary blends) were subjected to high-energy radiation, using a 60Co gamma radiation source. The crosslinked materials thus obtained were processed to heatshrinkable films. Tensile strength could be sharply improved by increasing the dose up to 20 Mrad, simultaneously increasing the elongation at break of the most degraded PE waste. An increase of the degree of compatibility of LDPE and HDPE waste was also observed. All samples examined exhibit a “memory effect” after drawing at 130°C and cooling under tension followed by further heating under relaxed conditions. The value of shrinkage depended on the degree …