| 1. |
- Banerjee, Sanjana, et al.
(författare)
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Invasive or Biomonitoring Species? Use of Pomacea maculata Operculum as a Tool to Determine Metal Pollutants : a Micro-PIXE Investigation
- 2023
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Ingår i: Water, Air and Soil Pollution. - : Springer Nature. - 0049-6979 .- 1573-2932. ; 234:6
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Tidskriftsartikel (refereegranskat)abstract
- Pomacea maculata is a widely distributed agricultural and environmental pest in Asia. It is also causing ecological damage and threatening human health in the Southeastern United States. However, its limited mobility and fast consumption of aquatic vegetation may make it an excellent biomonitor to evaluate the pollution status of freshwater coastal ecosystems. This work investigated the capability of the operculum of this snail to accumulate toxic metals in a laboratory environment. We measured the elemental composition of the nucleus and edge regions on the varnish layer of the operculum by employing a MeV ion microprobe instrument. Iron, copper, and zinc were present in the operculum at trace levels. Copper was present at elevated levels in the operculum of snails exposed to copper for 2 weeks. Additionally, heterogeneity in the distribution of major and trace elements within the gastropod's operculum was revealed by 2D elemental images obtained using microparticle-induced X-ray emission spectrometry. On average, the nucleus of the operculum showed a higher accumulation of copper than did the edge. These results demonstrate that micro-PIXE can be used to look at the within-tissue distribution of toxic metals in hard tissues like a snail's operculum. We propose that the operculum metal concentrations can be used as a bioindicator capable of providing information on the ecosystem's health and potentially reveal temporal changes in this health.
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| 2. |
- Carlén, Lars, et al.
(författare)
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CHICSi - a compact ultra-high vacuum compatible detector system for nuclear reaction experiments at storage rings. III. readout system
- 2004
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Ingår i: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - : Elsevier BV. - 0167-5087 .- 0168-9002. ; 516:2-3, s. 327-347
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Tidskriftsartikel (refereegranskat)abstract
- (CHICSi) Celsius Heavy Ion Collaboration Si detector system is a high granularity, modular detector telescope array for operation around the cluster-jet target/circulating beam intersection of the CELSIUS storage ring at the The. Svedberg Laboratory in Uppsala, Sweden. It is able to provide identity and momentum vector of up to 100 charged particles and fragments from proton-nucleus and nucleus-nucleus collisions at intermediate energies, 50-1000A MeV. All detector telescopes as well as the major part of electronic readout system are placed inside the target chamber in ultra-high vacuum (UHV, 10(-9)-10(-7) Pa). This requires Very Large Scale Integrated (VLSI) microchip for the spectroscopic signal processing and the generation and transport of digital control signals. Eighteen telescopes, read out with chip-on-board technique by ceramics Mother Boards (MB) and corresponding 18 microchips are mounted on a 450 x 45 mm(2) Grand Mother Board (GMB), processed on FR4 glass-fibre material. Each of these 28 GMB units contains a daisy-chain organisation of the VLSI chips and associated protection circuits. Analogue-to-digital conversion of the spectroscopic signals is performed on a board outside the chamber which is connected on one side to a power distribution board, directly attached to a UHV mounting flange, and on the other side to the VME-based data acquisition system (CHICSiDAQ). This in its turn is connected via a fibre-optic link to the general TSL acquisition system (SVEDAQ), and in this way data from auxiliary detector systems, read out in CAMAC mode, can be stored in coincidence with CHICSi data.
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| 3. |
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| 4. |
- Ekman, Jörgen, et al.
(författare)
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Retention of Pb isotopes in glass surfaces for retrospective assessment of radon exposure
- 2006
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Ingår i: Nuclear Instruments and Methods in Physics Research Section B. - : Elsevier. - 0168-583X .- 1872-9584. ; 249:1-2, s. 544-547
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Tidskriftsartikel (refereegranskat)abstract
- In recent years there has been increasing interest in radio-epidemiological techniques to retrospectively measure the radon dose exposure by determining the activity of 210Pb, the longest-lived 222Rn progeny, in glass surface layers. In this study the diffusion of 39 keV 209Pb+ ions implanted into glass using the IGISOL facility has been studied under conditions that mimic the recoil implantation of 210Pb from 222Rn. The resulting depth distributions of 209Pb were then measured after heat treatment in vacuum at different temperatures by a sputter erosion technique. The diffusion coefficient could be described by an Arrhenius equation D = D0exp(−H/kT) where and H = 2.81 ± 0.11 eV. No statistically significant loss of 209Pb from the sample was observed for annealing between 470 and 600 °C.
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| 5. |
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| 6. |
- Golubev, Pavel, et al.
(författare)
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CHICSi - a compact ultra-high vacuum compatible detector system for nuclear reaction experiments at storage rings. II. Detectors
- 2003
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Ingår i: Nuclear Instruments & Methods in Physics Research. Section A: Accelerators, Spectrometers, Detectors, and Associated Equipment. - 0167-5087. ; 500:1-3, s. 96-115
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Tidskriftsartikel (refereegranskat)abstract
- We describe the detectors for identification of charged particles and fragments in CHICSi, a large solid angle multitelescope system mounted inside an ultra-high vacuum (UHV), cluster-jet target chamber. CHICSi performs nuclear reaction experiments at storage rings. The telescopes consist of a first very thin, 10-14 mum Si detector, a second 300 mum (or possibly 500 pm) ion implanted Si detector supplemented by a 6 mm GSO(Ce) scintillator read out by a photodiode (PD) or by a third 300 mum Si detector. The telescopes provide full charge separation up to Z = 17 and mass resolution up to A = 9 in the energy range 0.7-60A MeV. The thin p-i-n diode detector, etched out from a 280 mum Si wafer, and the GSO/PD detector, both exclusively developed for CHICSi, provide an energy resolution less than or equal to 8%, while the standard 300 mum detectors have less than or equal to 2% energy resolution. Radiation stability of the Si detectors is confirmed up to an integrated flux of 10(10) alpha particles. The GSO detector has 70% light collection efficiency with the optical coupling to the PD a simple open, 0.2 mm, gap. A new method, developed to perform absolute energy calibration for the GSO/PD detector is presented. (C) 2003 Elsevier Science B.V. All rights reserved.
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| 7. |
- Gorelick, Sergey, et al.
(författare)
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Growth of osteoblasts on lithographically modified surfaces
- 2007
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Ingår i: Nuclear Instruments and Methods in Physics Research Section B. - : Elsevier. - 0168-583X .- 1872-9584. ; 260:1, s. 130-135
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Tidskriftsartikel (refereegranskat)abstract
- Here we report about preliminary investigations on developing substrates for culturing osteoblasts, the cells responsible for production of mineralised bone, by lithographically modifying the surfaces of several materials. The proton beam writing system at the National University of Singapore was used to fabricate high aspect ratio structures in PMMA, while two-dimensional low aspect ratio structures were fabricated using conventional electron beam lithography (EBL) and UV lithography (UVL) in SU-8. It was found that oxygen plasma treatment of structured SU-8 surfaces changed the surface layer and significantly improved cell attachment and proliferation. Cells grown on patterned thick PMMA exhibit a remarkable geometry-dependent behaviour.
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| 8. |
- Hellborg, Ragnar, et al.
(författare)
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Direct Current Accelerators for Industrial Applications
- 2011
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Ingår i: Reviews of Accelerator Science and Technology. - 1793-8058. ; 4:1, s. 183-212
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Tidskriftsartikel (refereegranskat)abstract
- Abstract in Undetermined Direct current accelerators form the basis of many front-line industrial processes. They have many advantages that have kept them at the forefront of technology for many decades, such as a small and easily managed environmental footprint. In this article, the basic principles of the different subsystems (ion and electron sources, high voltage generation, control, etc.) are overviewed. Some well-known (ion implantation and polymer processing) and lesser-known (electron beam lithography and particle-induced X-ray aerosol mapping) applications are reviewed.
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| 9. |
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| 10. |
- Joensson, C T, et al.
(författare)
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Synthesis and characterization of cobalt silicide films on silicon
- 2006
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Ingår i: Ion Beam Analysis - Proceedings of the Seventeenth International Conference on Ion Beam Analysis (Nuclear Instruments and Methods in Physics Research Section B: Beam Interactions with Materials and Atoms). - : Elsevier BV. - 0168-583X. ; 249, s. 532-535
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Konferensbidrag (refereegranskat)abstract
- Cobalt silicide has emerged as a leading contact material in silicon technology due to its low resistivity, high stability and small lattice mismatch. In this study, 0.2-0.4 mu m thick Co films were deposited on Si(100) wafers by RF magnetron sputtering at room temperature, and annealed at temperatures from 600 to 900 degrees C in vacuum. As-deposited and annealed samples were characterized by Rutherford backscattering spectrometry (RBS), nuclear reaction analysis (NRA), X-ray diffraction (XRD) and scanning electron microscopy (SEM). Although the Si substrates were sputter cleaned before the deposition, all the samples showed a thin oxide layer at the Si/Co interfaces. Annealing up to 700 degrees C did not alter the composition at the interface except small amount Co diffusion into Si. Annealing at 800 degrees C promotes the evaporation of the oxides from the interface and, as a result, clean CoSi2 films were formed. Although the interface appeared to be sharp within the RBS resolution after high temperature annealing, the surface topography was relatively rough with varying size of crystal grains. (c) 2006 Elsevier B.V. All rights reserved.
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