Search results for "RADIATION"
showing 10 items of 5298 documents
Dual Stimuli-Responsive Polysaccharide Hydrogels Manufactured by Radiation Technique
2022
Featured Application Stimuli-responsive hydrogels encompassing biobased polymers are anticipated for utilization in various fields, starting from drug delivery systems through temporal actuators and water reservoirs to biodegradable microelements and nutrient delivery depots. This paper describes the results of the radiation-induced crosslinking of polysaccharides modified with hydroxypropyl and carboxymethyl functional groups, hydroxypropylcellulose (HPC) and carboxymethylcellulose (CMC), respectively, without and with poly(ethylene glycol) diacrylate (PEGDA) as a crosslinking agent, to obtain dual stimuli-responsive hydrogels. The gels were characterized in terms of water uptake and gel f…
Study on heat transfer coefficients during cooling of PET bottles for food beverages
2015
The heat transfer properties of different cooling systems dealing with Poly-Ethylene-Terephthalate (PET) bottles were investigated. The heat transfer coefficient (Ug) was measured in various fluid dynamic conditions. Cooling media were either air or water. It was shown that heat transfer coefficients are strongly affected by fluid dynamics conditions, and range from 10 W/m2 K to nearly 400 W/m2 K. PET bottle thickness effect on Ug was shown to become relevant under faster fluid dynamics regimes.
Sun radiation and temperature impact at different periods of the year on the photooxidation of polyethylene films
2017
Analysis of the IR spectra of weathered films exposed at different periods of the year reveals that, the main regions of the IR spectrum affected by solar irradiation and temperature variation are the complex carbonyls and unsaturations composite absorption bands. Their respective kinetics vary in different manner according to the period at which the exposure is started. Curve fitting has been performed to refine the analysis of the IR spectra and to identify all the chemical species constituting the complex absorption bands. The analysis of the results let appears that whatever the exposure period of the year is, it does not affect the type of developing products, but it has strong effect …
Nanohybrid for Photodynamic Therapy and Fluorescence Imaging Tracking without Therapy
2018
Theranostic upconversion nanoparticles (UCNPs) are ideal candidates for personalized medicine. We present a smart, easy-to-prepare nanohybrid (NH) suitable for NIR-theragnosis and imaging tracking without triggering therapy simultaneously. The photophysical features of each component have been carefully selected in order to maximize the capabilities for theragnosis, in particular, the upconversion emission and the photosensitizer absorption. In addition, NH presents a fluorescent marker with one-photon absorption in the green and two-photon absorption cross-section at NIR wavelengths where the UCNP does not absorb, thus enabling innocuous tracking. Thus, the NH consists of NaYF4:Yb, Er, Tm …
Absence of correlated flux pinning by columnar defects in irradiated epitaxial Bi2Sr2CaCu2O8 thin films
1999
Abstract Using heavy-ion irradiation, we produced columnar defects of different density and orientation in epitaxial Bi 2 Sr 2 CaCu 2 O 8 thin films. Although this increases the normal state resistivity and the critical temperature is reduced proportionally to the volume fraction of damaged material, pinning-related quantities like critical current density, activation energy and depinning field are enhanced in external magnetic fields. Transport measurements in dependence of the magnetic field and its orientation consistently indicate two-dimensional pinning of pancake vortices at the columnar defects. We observe the absence of correlated flux pinning by columnar defects and compare to heav…
WITHDRAWN: Measurement of beam focus quality in biomedical nuclear microscopy.
2009
This article has been withdrawn at the request of the author(s) and/or editor. The Publisher apologizes for any inconvenience this may cause. The full Elsevier Policy on Article Withdrawal can be found at http://www.elsevier.com/locate/withdrawalpolicy.
Irradiated foods between concern and acceptance in the Italian market
2018
Consumers have always shown a marked concern for the novel technologies. The treatment of foods with ionizing radiation, not entirely new, has always been a major concern among consumers for the impact that the consumption of treated food could have on health. The aim of this paper is to investigate Italian consumer attitudes towards the irradiated food and in particular the perceived risk and the acceptability of these technology. A survey was carried out in Italy by administering an on-line questionnaire to a sample of 392 consumers. The results of the study highlight a low level of knowledge of food irradiation, often associated with nuclear radiation and doubts about the effect that the…
The identification of irradiated crustaceans and evaluation of the dose by thermoluminescence: Intercomparison between two methods for extracting min…
2010
Abstract The thermoluminescence (TL) is one of the physical methods recommended by the European Committee for Standardization, for the identification of irradiated food from which silicate minerals can be extracted. The efficacy of the method strongly depends on the quantity and purity of the extracted minerals, and therefore on the extraction procedure. In this work we applied the TL for the identification of crustacean Nephrops norvegicus irradiated at 0.5−1.5−3.0 kGy, comparing two different procedures for extracting minerals: by means of a density gradient or with acid hydrolysis. The identification of the irradiation treatment was always achieved with both procedures, without any false…
ISO 14470:2011 and EU legislative background on food irradiation technology: The Italian attitude
2014
Our work aim is to produce an overview of food irradiation technology at European Union level, with a focus on the Italian context, by specifying the legislative background, detection methods and labelling obligations. We highlight how consumers are too often misinformed about this technology and its benefits. For this purpose, a series of tools aimed at improving the amount of information have been proposed, allowing the consumer to make a free choice about whether or not to buy irradiated food based on the correct information received, independent from socio-economic factors. Finally, we show the common effort at EU and International level, represented by the ISO 14470:2011 quality standa…
Qualitative and quantitative thermoluminescence analysis on irradiated oregano
2007
Abstract Thermoluminescence (TL) dosimetry is one of the physical methods used for the identification of irradiated food, suitable for foods from which silicate minerals can be extracted. The aims of the present work were to apply the TL analysis for a qualitative identification of irradiated oregano, and to set up a quantitative procedure to estimate the original treatment dose on the sample. The experimental results show that the TL analysis allows to distinguish irradiated oregano even seven months after the treatment. The additive dose procedure gives a rough estimation of the treatment dose, but can be helpful when the TL ratio method is unsatisfactory.