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Silver nanoparticle accumulation by aquatic organisms – neutron activation as a tool for the environmental fate of nanoparticles tracing

: Chironomidae). Bull. Environ. Contam. Toxicol., 89, 245-250. DOI: 10.1007/s00128-012-0674-z. 17. Oughton, D. H., Hertel-AAS, T., Pollicer, E., Mendoza, E., & Joner, E. J. (2008). Neutron activation of engineered nanoparticles as a tool for tracing their environmental fate and uptake in organisms. Environ. Toxicol. Chem., 27(9), 1883-1887. DOI: 10.1897/07-578.1. 18. Bystrzejewska-Piotrowska, G., Asztemborska, M., Steborowski, R., Ryniewicz, J., Polkowska-Motrenko, H., & Danko, B. (2012). Application of neutron activaton for investigation of Fe3

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Operation modes of the FALCON ion source as a part of the AMS cluster tool

Abstract

The paper investigates the options to increase the production yield of temperature compensated surface acoustic wave (SAW) devices with a defined range of operational frequencies. The paper focuses on the preparation of large wafers with SiO2 and AlN/Si3N4 depositions. Stability of the intermediate SiO2 layer is achieved by combining high power density UV radiation with annealing in high humidity environment. A uniform thickness of the capping AlN layer is achieved by local high-rate etching with a focused ion beam emitted by the FALCON ion source. Operation parameters and limitations of the etching process are discussed.

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Metallurgical quality evaluation of the wind turbine main shaft 42CrMo4 steel: microscopic and Mössbauer studies

.11.004. 9. Huth, R. E. (2008, February). Vertical wind turbine shaft design trade study. Retrieved September, 23, 2016, from <http://www3.nd.edu/~me463c18/Trade%20Studies/TSHuth.pdf>. 10. Bała, P., Krawczyk, J., Hanc, A., & Dercz, G. (2010). The Mössbauer spectroscopy and X-ray diffraction studies of phase transformation during tempering in high-carbon tool steel. Solid State Phenom., 163, 200-203. DOI: 10.4028/www.scientific.net/SSP.163.200. 11. Min, N., Li, W., Li, H., & Jin, X. (2010). Atom probe and Mössbauer spectroscopy

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First dedicated observations of runaway electrons in the COMPASS tokamak

Abstract

Runaway electrons present an important part of the present efforts in nuclear fusion research with respect to the potential damage of the in-vessel components. The COMPASS tokamak a suitable tool for the studies of runaway electrons, due to its relatively low vacuum safety constraints, high experimental flexibility and the possibility of reaching the H-mode D-shaped plasmas. In this work, results from the first experimental COMPASS campaign dedicated to runaway electrons are presented and discussed in preliminary way. In particular, the first observation of synchrotron radiation and rather interesting raw magnetic data are shown.

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Synthesis of 11C-methionine through gas phase iodination using Synthra MeIPlus synthesis module

Abstract

A method of 11C-methionine synthesis using ‘bubbling’ method is presented. 11C-methionine was synthesized via 11C methylation from L-cysteine thiolactone (2 mg) in a 300 μL solution of 2:1:1 (v/v) 1 M NaOH, ethanol, and water at ambient temperature (85°C, 5 min). The radiochemical purity of radiotracer was higher than 99% and enantiomeric purity (L-11C-methionine) was 91.6 ± 0.4%. The final product met the requirements of European Pharmacopoeia monograph. The proposed 11C-methionine synthesis is a reliable tool for routine manufacturing in clinical applications and animal studies.

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Mean hyperfine fields at 57Fe in dilute iron-based alloys studied by Mössbauer spectroscopy

Abstract

The room temperature Mössbauer spectra of 57Fe were measured for numerous dilute iron-based alloys Fe1− xDx (D = Al, Co, Cr, Mn, Mo, Ni, Os, Pt, Re, Ru, Ta, Ti, V, W, Zn), annealed at 1270 K for 2 h before the measurements. The spectra were analyzed using the Hesse–Rübartsch method in order to determine the mean hyperfine magnetic field <B> at the 57Fe nuclei as a function of concentration x of the minority component of the alloy. As the binary alloys are one-faze solid solutions of an element D in iron, a linear relationship between <B> and x is observed. The result supports the suggestion that Mössbauer spectroscopy is a useful tool for the study of dissolution of different elements in iron.

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Diagnostic systems for the nuclear fusion and plasma research in the PF-24 plasma focus laboratory at the IFJ PAN

Abstract

This paper presents a set of diagnostics dedicated to PF-24 - new medium size - plasma focus (PF) device built and operated at the Institute of Nuclear Physics Polish Academy of Sciences (IFJ PAN). The PF-24 can operate at energy level up to 93 kJ and charging voltage up to 40 kV. Each condenser is connected with a specially designed spark gap with a very small jitter, which ensures a high effi ciency and a low current rise time. The working parameters of PF-24 generator make it a suitable tool for testing new detection systems to be used in fusion research. Four types of such detection systems are presented in this article: three diagnostic systems used to measure electric quantities (Rogowski coil, magnetic probe, capacitance probe), neutron counter based on beryllium activation, fast neutron pinhole camera based on small-area BCF-12 plastic scintillation detectors and high-speed four-frame soft X-ray camera with microchannel plate.

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Imaging of hypoxia in small animals with 18F fluoromisonidasole

Abstract.

A method of automated synthesis of [18F]fluoromisonidazole ([18F]FMISO) for application in preclinical studies on small animals was presented. A remote-controlled synthesizer Synthra RNplus was used for nucleophilic substitution of NITTP (1′-(2′-nitro-1-imidazolyl)-2-O-tetrahydropyranyl-3-O-toluenesulfonyl-propanediol) with 18F anion. Labeling of 5 mg of precursor was performed in anhydrous acetonitrile at 100°C for 10 min, and the hydrolysis with HCl was performed at 100°C for 5 min. Final purification was done with high-performance liquid chromatography (HPLC) and the radiochemical purity of radiotracer was higher than 99%. Proposed [18F]FMISO synthesis was used as a reliable tool in studies on hypoxia in Lewis lung carcinoma (LLC) in mouse models.

Open access
Technetium-99m: From nuclear medicine applications to fine sediment transport studies

Abstract

The present work is a contribution to rescue the history of development of the application of 99mTc, widely used in nuclear medicine, to its use as tracer for the study of the transport of fine sediment in suspension, in water environment. It addresses the usefulness of its application in obtaining important parameters in environmental studies, illustrating them with some applications already performed and the results obtained. This kind of study, when associated with information on hydrodynamic parameters, for example, river, tidal, wind and wave currents, are powerful tools for the understanding and quantification of fine sediment transport in suspension. Fine sediment is an important vector in the transportation of heavy metals, organic matter and nutrients in water environment, and the quantitative knowledge of its behaviour is mandatory for studies of environmental impacts. Fine sediment labelled with 99mTc, can also be used to study the effect of human interventions, such as dredging of reservoirs, access channels and harbours, and the dumping of dredged materials in water bodies. Besides that, it can be used to optimize dredging works, evaluating the technical and economic feasibility of dumping sites and their environmental impact. It is a valuable support in the calibration and validation of mathematical models for sediment dynamics.

Open access
Monte Carlo calculated CT numbers for improved heavy ion treatment planning

Abstract

Better knowledge of CT number values and their uncertainties can be applied to improve heavy ion treatment planning. We developed a novel method to calculate CT numbers for a computed tomography (CT) scanner using the Monte Carlo (MC) code, BEAMnrc/EGSnrc. To generate the initial beam shape and spectra we conducted full simulations of an X-ray tube, filters and beam shapers for a Siemens Emotion CT. The simulation output files were analyzed to calculate projections of a phantom with inserts. A simple reconstruction algorithm (FBP using a Ram-Lak filter) was applied to calculate the pixel values, which represent an attenuation coefficient, normalized in such a way to give zero for water (Hounsfield unit (HU)). Measured and Monte Carlo calculated CT numbers were compared. The average deviation between measured and simulated CT numbers was 4 ± 4 HU and the standard deviation σ was 49 ± 4 HU. The simulation also correctly predicted the behaviour of H-materials compared to a Gammex tissue substitutes. We believe the developed approach represents a useful new tool for evaluating the effect of CT scanner and phantom parameters on CT number values.

Open access