Search results for "HAZE"

TI: Cyclophosphazenes as polymer modifiers

2003

The utilization of cyclophosphazenes as polymer modifiers is reviewed, with particular concern to their exploitation as versatile chain extenders, possibly for recycle problems, crosslinkers, to enhance mechanical properties of polymeric materials, branchers, to selectively introduce ramifications in linear polymers, and compatibilizers, to favor the formation of blends between originally incompatible organic macromolecules. The great versatility of the synthetic methods put forward for these substrates, together with the ease of controlling their modification, functionalization and reactivity are important parameters for the evaluation of which type of use is more feasible for these trimer…

New phosphazene-based chain extenders containing allyl and epoxide groups

2003

In this paper we present the synthesis and the characterization of cyclophosphazenes substituted with allyl groups, their transformation in epoxide-containing cyclophosphazenes and the final utilization of these compounds as chain extenders in combination with polyamides. The reaction at high temperature of Nylon-6 with epoxy-functionalized cyclophosphazenes leads to the opening of the epoxy units by the action of both amino (--NH2) and carboxylic (--COOH) end-groups of the polymer to enhance the final molecular weight of this material. The consequences of this fact on the thermal, mechanical and visco-elastic properties of treated Nylon-6 have been also evaluated and compared to those of t…

L'affaire Doize (1861-1862). Du trou noir d'Hazebrouck à la réforme de la procédure pénale

2004

Direct Objective Quantification of Corneal Haze after Excimer Laser Photorefractive Keratectomy for High Myopia

1996

Purpose: The purpose of the study is to measure regional distribution differences in corneal haze after excimer laser photorefractive keratectomy for high myopia. Methods: The authors developed computerized gradient edge detectors with which were analyzed digitized anterior slit-lamp photographs of 40 eyes, an average of 21.0 plus or minus 14.5 weeks after photorefractive keratectomy for high myopia (−6 to −22 diopters). A treated area and an adjacent untreated area on the anterior corneal surface, each containing six regions, were quantified, and the difference was correlated with various parameters. Results: Mean differences between scarred and clear areas for haze grade 0.5, 1.0, 2.0, 3.…

Efficient blue emitting organic light emitting diodes based on fluorescent solution processable cyclic phosphazenes

2008

Solution processable blue fluorescent dendrimers based on cyclic phosphazene (CP) cores incorporating amino-pyrene moieties have been prepared and used as emissive layers in organic light emitting diodes (OLEDs). These dendrimers have high glass transition temperatures, are monodisperse, have high purity via common chromatographic techniques, and form defect-free amorphous films via spin/dip coating. The solution processable blue light emitting OLEDs reach current efficiencies of 3.9 cd/A at brightness levels near 1000 cd/m2. Depending on the molecular bridge used to attach the fluorescent dendron to the inorganic core, the emission wavelength changes from 470 to 545 nm, corresponding to bl…

Titan's surface and atmosphere from Cassini/VIMS data with updated methane opacity

2013

International audience; We present an analysis of Titan data acquired by the Cassini Visual and Infrared Mapping Spectrometer (VIMS), making use of recent improvements in methane spectroscopic parameters in the region 1.3-5.2 μm. We first analyzed VIMS spectra covering a 8 × 10-km2 area near the Huygens landing site in order to constrain the single scattering albedo (ω0) of the aerosols over all of the VIMS spectral range. Our aerosol model agrees with that derived from Huygens Probe Descent Imager/Spectral Radiometer (DISR) in situ measurements below 1.6 μm. At longer wavelengths, ω0 steadily decreases from 0.92 at 1.6 μm to about 0.70 at 2.5 μm and abruptly drops to about 0.50 near 2.6 μm…

Influence of polysaccharides on wine protein aggregation.

2016

Abstract Polysaccharides are the major high-molecular weight components of wines. In contrast, proteins occur only in small amounts in wine, but contribute to haze formation. The detailed mechanism of aggregation of these proteins, especially in combination with other wine components, remains unclear. This study demonstrates the different aggregation behavior between a buffer and a model wine system by dynamic light scattering. Arabinogalactan-protein, for example, shows an increased aggregation in the model wine system, while in the buffer system a reducing effect is observed. Thus, we could show the importance to examine the behavior of wine additives under conditions close to reality, in…

Spatial distribution of the arctic haze aerosol size distribution in western and eastern Arctic

1997

Abstract Since June 1993, four flight campaigns to the Arctic have been carried out by a group of scientists from Russia and Germany. Optical remote-sensing methods and in-situ chemical and aerosol measurements have been combined on board a Russian IL-18 research aircraft. From arctic air bases in Siberia, Alaska, Canada, and Spitsbergen, respectively, flights have been undertaken to determine spatial structure of arctic haze events. This paper reports on aerosol data obtained during the expedition of Spring 1994. Haze events have been found in the east and west Arctic, containing about the same concentration of particles. Horizontal and vertical layer extensions are given and the size dist…

Detection potential of the KM3NeT detector for high-energy neutrinos from the Fermi bubbles

2013

A recent analysis of the Fermi Large Area Telescope data provided evidence for a high-intensity emission of high-energy gamma rays with a E-2 spectrum from two large areas, spanning 50 above and below the Galactic centre (the "Fermi bubbles"). A hadronic mechanism was proposed for this gamma-ray emission making the Fermi bubbles promising source candidates of high-energy neutrino emission. In this work Monte Carlo simulations regarding the detectability of high-energy neutrinos from the Fermi bubbles with the future multi-km(3) neutrino telescope KM3NeT in the Mediterranean Sea are presented. Under the hypothesis that the gamma-ray emission is completely due to hadronic processes, the resul…

LEAD(II) AND CADMIUM(II) REMOVAL FROM AQUEOUS SOLUTIONS USING HAZELNUT AND ALMOND SHELLS SORBENT MATERIALS

2016

Removal of toxic metal ions from natural and waste waters is of great importance for the health of living organisms and for environmental protection. Alternatively to the conventional chemical treatments, such as precipitation, reverse osmosis, etc, biosorption shows a growing interest for toxic metal ions removal from contaminated aqueous solutions. The sorption ability of every type of biomass towards metal ions depends on many variables that characterize the solution. Among these, the ionic strength (I) is one of the most important and cannot be neglected during an accurate adsorption study. For this reason and with the aim of quantitatively define the influence of I, here are reported t…