Search results for "High pressure"
showing 10 items of 894 documents
ChemInform Abstract: Tuning the Band Gap of PbCrO4Through High-Pressure: Evidence of Wide-to-Narrow Semiconductor Transitions.
2014
Commercial polycrystalline and cleaved platelets from natural PbCrO4 are studied in a diamond anvil cell at ≤ 21 GPa.
Illicit drugs consumption evaluation by wastewater-based epidemiology in the urban area of Palermo city (Italy)
2017
Introduction. A wastewater-based epidemiology approach was performed to estimate the drug consumption in Palermo city, the fifth largest city of Italy with a population of 671 696 inhabitants, and to investigate the monthly variability of drug loads in wastewater from different areas of the city. A seven-months detection campaign was conducted at the two wastewater treatment plants of the city. Methods. Following a pre-treatment, 32 samples of wastewater were analyzed by liquid chromatography-tandem mass spectrometry. Results. We estimated a mean cocaine use in Palermo of 0.19 g/day/1000 people, corresponding to 1.90 doses/1000 people and cannabinoids use of 2.85 g/day/1000 people, correspo…
Plasticizer extraction of Taxol infusion solution from various infusion devices.
1996
Taxol solution extracts the plasticizer DEHP (di(2-ethylhexyl)phthalate) from polyvinyl chloride (PVC) materials. In order to minimize patient exposure to DEHP, Taxol solutions should be prepared and administered in PVC-free materials. Particulate matter may form in Taxol infusion solution over time, so that in-line filtration with microporous membranes not greater than 0.22 microns is advisable. The purpose of this study was to evaluate the suitability of various administration- and in-line filter-sets for Taxol application. The extent of leached DEHP was determined using a Reversed Phase HPLC assay specific for DEHP. The four tested administration-sets, labeled as PVC-free, were all found…
Classification of olive leaves and pulp extracts by comprehensive two-dimensional liquid chromatography of polyphenolic fingerprints.
2019
Abstract The development of a new comprehensive two-dimensional liquid chromatographic method is described, to obtain the profiles of polyphenolic compounds present in olive (Olea europaea L.) leaves and pulps from different genetic origin. Optimisation of the stationary phase nature, particle size, column length and internal diameter, as well as other separation conditions, was performed. Along the study, three stationary phases (C18, PFP and phenyl) in the first dimension (1D), and five (C18, amide, cyano, phenyl and PFP) in the second dimension (2D) were combined to obtain the maximal number of resolved peaks. The optimised method successfully characterised the presence of 26 and 29 comm…
Combined use of modified atmosphere packaging and high pressure to extend the shelf-life of raw poultry sausage
2014
International audience; The contribution of modified atmosphere packaging (MAP) in extending the shelf-life of high-pressure treated raw poultry sausages was examined by considering microbial and oxidative stability (TBARs) aspects. Raw poultry sausages packaged under air or modified atmosphere (50% CO2–50% N2) were pressurized at 500 MPa during 5 min at a maximum temperature of 10.5 °C, subsequently allowed to refrigerated storage during 22 days. During storage, samples were tested at time intervals for headspace gas composition, pH, TBARs, Aerobic Mesophilic Counts (AMC) and Lactic Acid Bacteria (LAB) counts. The high pressure treatment could represent an efficient means of extending the …
New opportunities and perspectives of high pressure treatment to improve health and safety attributes of foods. A review
2015
Abstract High pressure (HP) treatment has emerged as a novel, additive-free food preservation technology. It has been scientifically and commercially proven that HP can produce microbially safe and stable products with improved quality characteristics such as enhanced flavor and color. Recent studies have focused on the effects of HP on health attributes and allergenic potential of foodstuff to develop the next generation of convenience foods. This review provides an overview on the current knowledge of HP treatment to improve the extraction and bioavailability of bioactive compounds, to reduce allergenicity, to retain essential fatty acids, to reduce the salt content, and to reduce formati…
Eclogites within the Menderes Massif / western Turkey
1997
Metagabbros in the core series of the Menderes Massif, for some time considered as post orogenic Miocene intrusives, revealed a strong poly-metamorphic history. The metagabbro bodies exhibit a pronounced zonation. Within their cores, igneous minerals are still preserved. Coronitic textures are interpreted as results of a high temperature, possibly granulitic overprint. The outer parts of the metagabbro bodies mostly consist of strongly to completely retrograded gamet-amphibo-lites, but occasionally contain relies of eclogites. Petrologic investigations confirmed a high pressure overprint and allowed preliminary P, T estimates (650 degrees C, equal to or greater than 1.3 GPa). The intensity …
Aggregation properties of proteins under high pressure
2010
Fourier transform infrared spectroscopy (FTIR) coupled with High Pressure (HP) techniques is a suitable tool to investigate unfolding/misfolding processes providing useful information on the kinetics of aggregation of proteins[1]. Since HP affects only the volume contribution to the Gibbs free energy, it is able to perturb the structure of proteins in a reversible way [2][3]. The principle governing pressure effects is that it tends to shift a system towards the state that occupies the smallest volume, it causes the electrostriction of charged and polar groups, the elimination of packing defects, and the solvation of hydrophobic groups. Cavities and packing defects are expected to be major …
Infrared HP study of protein folding and aggregation @ the SISSI Elettra beamline
2010
Fourier transform infrared spectroscopy (FTIR) coupled with High Hydrostatic Pressure technology is a suitable technique to investigate unfolding/misfolding processes providing useful information on the kinetics of aggregation of proteins. Since HHP doesn't affect the enthalpic contribution to the Gibbs free energy, it is able to perturb the secondary structure of proteins in a reversible way . The principle governing pressure effects is that it tends to shift a system towards the state that occupies the smallest volume, it causes the electrostriction of charged and polar groups, the elimination of packing defects, and the solvation of hydrophobic groups. Cavities and packing defects are ex…
FTIR studies of the high pressure dissociation of insulin and alpha-synuclein amyloids
2012
Amyloid fibrils are highly ordered aggregates whose formation occurs during the development of several serious disorders, like Althzeimer's and Parkinson's diseases. Even if most biophysical investigations of fibril formation have attempted to elucidate the structural events that occur during amyloid fibril assembly, relatively little is known about the thermodynamics of the aggregated protein state, and the kinetic mechanisms of its formation. Fibrillation is an irreversible process and a key challenge for the field is the development of therapeutic strategies able to inhibit or reverse the aggregation. The coupling of conventional Fourier Transform Infrared Spectroscopy (FTIR) and high Pr…