Search results for " Irradiation"

Photodegradation of selected phthalates on mural painting surfaces under UV light irradiation

2014

Abstract The esters of phthalic acid are considered as hazardous pollutants due to their mutagenicity, carcinogenicity and are also classified as endocrine disruptor chemicals. Several compounds of this class of substances for decades, and probably even now, were used as softeners in water-based synthetic paintings. Surfaces and structures, such as house walls painted with phthalates based paintings, can be a concern to construction workers engaged in demolition, restore and paint removal activities if they are not protected from hazardous dust inhalation. In this paper we report the results of an investigation about phthalate ester degradation by direct UV irradiation at 254 nm. The result…

Palladium nanoparticles immobilized on halloysite nanotubes covered by a multilayer network for catalytic applications

2018

The synthesis of pure fine chemicals for industrial purposes is one of the most attractive challenges of chemical research. The use of catalytic pathways mediated by palladium nanoparticles (PdNPs) for C-C bond formation is a useful way to obtain these kinds of compounds. To achieve this objective, the PdNPs can be efficiently loaded on a functionalized natural nanostructured support such as halloysite nanotubes (HNTs). Hybrid materials based on thiol functionalized halloysite nanotubes and highly cross-linked imidazolium salts were successfully developed and used for the stabilization of PdNPs. The HNT/Pd hybrids were thoroughly characterized from a physico-chemical point of view and teste…

On thermo-mechanical issues induced by irradiation swelling inside the back-plate of the IFMIF target assembly

2011

Abstract Within the framework of the IFMIF R&D program and in close cooperation with ENEA-Brasimone, at the Department of Nuclear Engineering of the University of Palermo a research campaign has been launched to investigate the thermo-mechanical issues potentially induced by irradiation swelling in the threaded connections between frame and back-plate of IFMIF target assembly. The main aim of the research campaign has relied in the assessment of the maximum swelling-induced volumetric strain that may be accepted in order to allow screws to withstand thermo-mechanical stresses and work in safe conditions or to avoid unduly high unscrewing torques during back-plate remotely handled maintenanc…

Adipose tissue sensitivity to radiation exposure

2008

1525-2191 (Electronic) Journal Article Research Support, Non-U.S. Gov't; Treatment of cancer using radiation can be significantly compromised by the development of severe acute and late damage to normal tissue. Treatments that either reduce the risk and severity of damage or that facilitate the healing of radiation injuries are being developed, including autologous adipose tissue grafts to repair tissue defects or involutional disorders that result from tumor resection. Adipose tissue is specialized in energy storage and contains different cell types, including preadipocytes, which could be used for autologous transplantation. It has long been considered a poorly proliferative connective ti…

Contribution of different bone marrow-derived cell types in endometrial regeneration using an irradiated murine model.

2015

Objective To study the involvement of seven types of bone marrow-derived cells (BMDCs) in the endometrial regeneration in mice after total body irradiation. Design Prospective experimental animal study. Setting University research laboratories. Animal(s) β-Actin-green fluorescent protein (GFP) transgenic C57BL/6-Tg (CAG-EGFP) and C57BL/6J female mice. Intervention(s) The BMDCs were isolated from CAG-EGFP mice: unfractionated bone marrow cells, hematopoietic progenitor cells, endothelial progenitor cells (EPCs), and mesenchymal stem cells (MSCs). In addition three murine GFP + cell lines were used: mouse Oct4 negative BMDC multipotent adult progenitor cells (mOct4 − BM-MAPCs), BMDC hypoblast…

Concrete thermal energy storage for linear Fresnel collectors: Exploiting the South Mediterranean’s solar potential for agri-food processes

2018

Abstract Italy is celebrated in the world for its agri-food industries while the process of production of pasta is highly energy demanding and requires both electrical and thermal energy simultaneously. Because most of the Italian factories producing pasta are located in the Southern part of the country, the direct use of thermal energy generated from the sun would be particularly profitable. In this study, the authors examine the possibility of generating by a Solar Industrial Process Heating plant the thermal energy required annually by an existing factory that produces durum wheat pasta located in Sicily (Italy). The hypothesized plant scheme consists of an array of Fresnel linear solar …

A methacrylic hyaluronic acid derivative for potential application in oral treatment of celiac disease.

2017

Objective: Aim of this work was the synthesis of a methacrylic hyaluronic acid (HA) derivative and the production, via photocrosslinking, of related hydrogels loaded with an endopeptidase intended for a potential oral treatment of celiac disease. Methods: The methacrylic derivative of HA was prepared through a one-pot procedure involving the reaction with ethylenediamine (EDA) and methacrylic anhydride (MA). The obtained derivative, named HA-EDA-MA, was used to prepare photocrosslinked hydrogels loaded with a prolyl endopeptidase derived from Flavobacterium meningosepticum (PEP FM) able to detoxify gliadin. Obtained hydrogels were recovered as gels or freeze-dried powders. Results: Hydrogel…

Phase State and Structure of Ferroelectric Ceramics under Irradiation

1997

Photoluminescent and paramagnetic centers in gamma irradiated porous silica

2005

Abstract The photoluminescence and electron spin resonance properties of gamma irradiated (up to 500 kGy) porous silica are reported. By exciting at 5.6 eV a photoluminescence contribution can be detected before irradiation, peaked at about 4.1 eV. Gamma irradiation causes the generation of the E′ centers (about 1 × 1014 defects cm−3) of paramagnetic hole centers and modifies the photoluminescence properties of the sample: the emission amplitude decreases and three contributions can be singled out at about 3.3, 3.8 and 4.4 eV.

Facile synthesis of L-cysteine functionalized graphene quantum dots as a bioimaging and photosensitive agent

2021

Nowadays, a larger number of aggressive and corrosive chemical reagents as well as toxic solvents are used to achieve structural modification and cleaning of the final products. These lead to the production of residual, waste chemicals, which are often reactive, cancerogenic, and toxic to the environment. This study shows a new approach to the modification of graphene quantum dots (GQDs) using gamma irradiation where the usage of reagents was avoided. We achieved the incorporation of S and N atoms in the GQD structure by selecting an aqueous solution of L-cysteine as an irradiation medium. GQDs were exposed to gamma-irradiation at doses of 25, 50 and 200 kGy. After irradiation, the optical,…