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DOI 10.1515/polyeng-2011-0136   J Polym Eng 2012; 32: 379–388 Rajiv Pradhan , Arnab Shanker Bhattacharyya , Nilay Pramanik , Ramsankar Haldar , Utpal Kumar Niyogi , Rakesh Kumar Khandal and Shantanu Bhowmik * Investigation on Nylon 66 silicate nanocomposites modified under gamma radiation Abstract: This investigation highlights the processing of Nylon 66 and the incorporation of nano-silicate into the Nylon 66 polymeric matrix. Further, radiation modifica- tion of Nylon 66 and nano-silicate dispersed Nylon 66 was carried out in order to

ISSN 1203-8407 © 2016 Science & Technology Network, Inc. J. Adv. Oxid. Technol. Vol. 19, No. 1, 2016 73 A Biodegradation Bench Study of Cork Wastewater using Gamma Radiation Célia Lima 1, 2 , Joana Madureira 1 , Rita Melo 1 , Maria M. Carolino 2 , João P. Noronha 3 , Fernanda M. A. Margaça 1 , Sandra Cabo Verde* , 1 1 Centro de Ciências e Tecnologias Nucleares (C2TN), Instituto Superior Técnico, Universidade de Lisboa, Estrada Nacional 10, km 139.7, 2695-066 Bobadela, Loures, Portugal 2 Centro de Biologia Ambiental, Departamento de Biologia

one certain specie set per 100 eV. There are three reactive species with higher G value, including hydroxyl radicals (˙OH), hydrated electrons (e aq − ) and hydrogen atoms (˙H). They play an important role in the radiation process for pharmaceuticals degradation in water. Figures 2 and 3 show gamma radiation-induced SMT degradation in aqueous solutions with the increasing absorbed dose. The initial concentration of SMT was 20 mg/L. The radiation doses used in the experiment were 1, 2, 3, 4 and 5 kGy. One sample without radiation was used as a negative control

by gamma radiation R o s a Jim é n e z and A d e la O h lb a u m Instituto de Ciencias and Departamento de Virologia de la Facultad de Medicina, Universidad de Chile (Z. Naturforschg. 21 b, 52— 55 [19 6 6 ]; eingegangen am 31. August 1965) The influence of the purification on the inactivation of Vaccinia Virus (VV) by gamma radiation has been studied. Differential centrifugation and sucrose density gradient centrifugation have been used. Purification modifies the VV compound survival curve previously published 2. The possibility that multiple reactivation

Radiochim. Acta 98, 243–247 (2010) / DOI 10.1524/ract.2010.1704 © by Oldenbourg Wissenschaftsverlag, München Effects of gamma radiation on electrochemical properties of ionic liquids By N. J. Bridges∗, A. E. Visser, M. J. Williamson, J. I. Mickalonis and T. M. Adams Savannah River National Laboratory, Mail Stop 20, Aiken, SC 29808, USA (Received May 15, 2009; accepted in final form October 29, 2009) Ionic liquids / Electrochemical window / Irradiation Summary. The electrochemical properties of ionic liquids (ILs) make them attractive for possible replacement of

, 34% phosphate) and nitrogen-phosphate-potassium (NPK) with composition of (20% nitrogen, 20% potassium, 20% phosphate) were supplied from Semadco – El-Nasr company for fertilizers and chemical industries. Zea maize seeds were supplied from the national company for seeds production and agricultural crops, Egypt. 2.2 Preparation of PVP/CMC superabsorbent hydrogels PVP/CMC superabsorbent hydrogels were prepared by gamma radiation-induced crosslinking with different doses and different copolymer compositions. A certain amount, 5 g of PVP and CMC were dissolved in 100

Abstract

Graphene oxide-polyvinyl chloride composite was prepared using tetrahydrofuran solvent-assisted dispersion of characterized nano flakes of graphene oxide in polymer matrix. Electrical percolation threshold of GO/PVC nanocomposite was determined via a finite element simulation method with a 2D model and compared with experimental results. A conductive cell with two silver coated walls was designed and fabricated for exploring dosimetric properties of the composite. Some characteristics of the new nanocomposite such as linearity of dose response, repeatability, sensitivity and angular dependence are investigated. According to 2D proposed method, obtained data associated to electrical conductivity of the GO/polymer composite for PVC matrix plotted in different GO weight percentages and had good compatibility (validity) with experimental data. The dose response is linear in the 17–51 mGy dose range and it can be introduced for gamma radiation dosimetry in diagnostic activities.

Abstract

During the operation of large industrial installations, a very important task is to maintain the proper technical state. In the event of an emergency, it is vital to locate the place of occurrence as soon as possible. In solving this type of problem, it often helps to apply the methods of measurement associated with ionizing radiation. One of these methods is the gamma scanning. The purpose of this type of measurement is the detection and localization of disturbance of technological processes which may result in incorrect decomposition the fl owing medium and workpiece (sediments, congestion) as well as damage to the internal constructions. A particularly: (i) preventive diagnosis - early detection of installation failure; (ii) rationalization of repairs and renovations - to determine the need to take or not to take remedial action; (iii) quick and precise installation inspections - to gain knowledge of the technical condition and technological installations; (iv) indication of worn parts and posing a threat - diagnostics of the technical condition installation; (v) forecasting the useful lifetime of equipment.

Holzforschung, Vol. 61, pp. 267–271, 2007 • Copyright by Walter de Gruyter • Berlin • New York. DOI 10.1515/HF.2007.064 Article in press - uncorrected proof Changes in physical, mechanical and chemical properties of wood during sterilisation by gamma radiation Radovan Despot1,*, Marin Hasan1, Christian Brischke2, Christian Robert Welzbacher2 and Andreas Otto Rapp2 1 Faculty of Forestry, University of Zagreb, Zagreb, Croatia 2 Federal Research Centre for Forestry and Forest Products (BFH), Hamburg, Germany *Corresponding author. Faculty of Forestry, Institute of

Abstract

The aim of this study is to exploit a suitable chitosan extraction method from the chitin of indigenous shrimp shells by employing different physicochemical treatments and to improve different bioactive properties of this extracted chitosan (CS) by applying gamma radiation. Chitin was prepared from shrimp shell by pretreatment (deproteination, demineralization and oxidation). Chitosan was extracted from chitin by eight different methods varying different physicochemical parameters (reagent concentration, temperature and time) and assessed with respect to the degree of deacetylation, requirement of time and reagents. The method where chitin was repeatedly treated with 121°C for 30 min with 20 M NaOH, produced the highest degree of deacetylation (DD) value (92%) as measured by potentiometric titration, with the least consumption of time and chemicals, and thus, selected as the best suitable extraction method. For further quality improvement, chitosan with highest DD value was irradiated with different doses (i.e., 5, 10, 15, 20 and 50 kGy) of gamma radiation from cobalt-60 gamma irradiator. As the radiation dose was increased, the molecular weight of the wet irradiated chitosan, as measured by the viscosimetric method, decreased from 1.16 × 105 to 1.786 × 103, 1.518 × 103, 1.134 × 103, 1.046 × 103 and 8.23 × 102 dalton, respectively. The radiation treatment of chitosan samples increased the antimicrobial activity significantly in concentration dependent manner on both gram-positive (Staphylococcus aureus) and gram-negative (Escherichia coli) bacteria, as determined by the well-diffusion method. Four to five percent wet chitosan treated with a radiation dose range of 5.0–10.0 kGy rendered the highest antimicrobial activity with least energy and time consumption. Solubility, water binding capacity (WBC) and fat binding capacity (FBC) also improved due to irradiation of chitosan.