| 1. |
- Ciesla, K, et al.
(författare)
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DSC studies of gamma irradiation influence on gelatinisation and amylose-lipid complex transition occurring in wheat starch.
- 2003
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Ingår i: Radiation Physics and Chemistry. - 0969-806X. ; 68:5, s. 933-940
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Tidskriftsartikel (refereegranskat)abstract
- Differential scanning calorimetry studies are presented dealing with the influence of gamma irradiation (carried out in the solid state) on the structure of amylose–lipid complex in wheat starch. Suspensions of the control and the wheat starch irradiated with a 30 kGy gamma rays (characterised by starch-to-water ratio of 1:1 and ca. 1:4) were examined during several courses of heating and cooling at rates of 2.5 and 10°C min−1. Differences were observed between enthalpy and temperature of gelatinisation and amylose–lipid complex transition as well as retrogradation taking place in the suspensions and gels of the control and the irradiated starch. The influence of the preceding heating and cooling on further transformations of the amylose–lipid complex differs for the control and the irradiated samples.
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| 2. |
- Ciesla, K, et al.
(författare)
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Influence of gamma radiation on potato starch gelatinization studied by differential scanning calorimetry
- 2002
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Ingår i: Radiation Physics and Chemistry. - 0969-806X. ; 64:2, s. 137-148
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Tidskriftsartikel (refereegranskat)abstract
- The paper presents a study of the influence of the conditions applied during differential scanning calorimetry (DSC) Measurements (concentration and heating rate) oil the possible detection of the differences between gelatinization occuring in both non-irradiated and irradiated potato starch with a dose of 20kGy. Differences in gelatinization of irradiated and non-irradiated potato starch during DSC analysis was attributed to the radiation induced destruction of crystalline ordering. This was confirmed by studies of the samples irradiated to very high doses (446 and 600 kGy). and by comparing with the effect of grinding. Changes of starch properties caused by radiodepolymerization-contrary to those caused by grinding influences gelatinization behaviour much more than the WAXS crystallinity in solid state. (C) 2002 Elsevier Science Ltd. All rights reserved.
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| 3. |
- Lundstrom, T., et al.
(författare)
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The reaction of OH with H at elevated temperatures
- 2002
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Ingår i: Radiation Physics and Chemistry. - 0969-806X .- 1879-0895. ; 64:1, s. 29-33
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Tidskriftsartikel (refereegranskat)abstract
- The temperature dependence of the rate constant for the reaction between OH radicals and H atoms has been determined in Ar-saturated solutions at pH 2. The reaction was studied in the temperature range 5-233°C. The rate constants at 20°C and 200°C are 9.3×109 and 3.3×1010dm3mol-1s-1, respectively. The activation energy was found to be 8.2±0.4kJmol-1 (2.0±0.1kcalmol-1). This value is lower than that expected for a diffusion controlled reaction. © 2002 Elsevier Science Ltd. All rights reserved.
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| 4. |
- Lundström, Tim, et al.
(författare)
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The reaction of hydrogen atoms with hydrogen peroxide as a function of temperature
- 2001
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Ingår i: Radiation Physics and Chemistry. - 0969-806X .- 1879-0895. ; 61:2, s. 109-113
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Tidskriftsartikel (refereegranskat)abstract
- The temperature dependence for the reaction of H atoms with H2O2 at pH 1 has been determined using pulse radiolysis technique. The reaction was studied in the temperature range 10-120°C. The rate constant at 25°C was found to be 5.1 ± 0.5 × 107 dm3 mol-1 s-1 and the activation energy was found to be 10.7 ± 0.5 kJ mol-1. © 2001 Published by Elsevier Science Ltd.
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| 5. |
- Schuch, R, et al.
(författare)
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High resolution studies of electron-ion recombination
- 2003
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Ingår i: Radiation Physics and Chemistry. - 0969-806X. ; 68:1-2, s. 51-56
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Tidskriftsartikel (refereegranskat)abstract
- The formation of atoms by recombination of free electrons with ions is a fundamental process and plays a central role in astro-physical and fusion plasmas. It can be seen as time-inverse photo-ionization, auto-ionization, or electron-impact ionization. Here, we show how these processes can be measured with cooler-storage rings, such as CRYRING at MSL, with very high accuracy. The status of theoretical modeling is briefly reviewed and anomalies are uncovered. We discuss some examples of recombination for ions where strong dielectronic recombination resonances occur. With cooler-storage rings, these resonances can today be measured with meV accuracy, and from the spectra of the dielectronic resonances, very accurate values for energy splittings and resonance strengths are derived. These allow crucial tests of relativistic, correlation, and QED effects in these systems.
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| 6. |
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| 7. |
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| 8. |
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| 9. |
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| 10. |
- Alcayne, V., et al.
(författare)
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A Segmented Total Energy Detector (sTED) optimized for (n,ϒ) cross-section measurements at n_TOF EAR2
- 2024
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Ingår i: Radiation Physics and Chemistry. - : Elsevier. - 0969-806X .- 1879-0895. ; 217
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Tidskriftsartikel (refereegranskat)abstract
- The neutron time-of-flight facility n_TOF at CERN is a spallation source dedicated to measurements of neutroninduced reaction cross-sections of interest in nuclear technologies, astrophysics, and other applications. Since 2014, Experimental ARea 2 (EAR2) is operational and delivers a neutron fluence of similar to 4 center dot 10(7) neutrons per nominal proton pulse, which is similar to 50 times higher than the one of Experimental ARea 1 (EAR1) of similar to 8 center dot 10(5) neutrons per pulse. The high neutron flux at EAR2 results in high counting rates in the detectors that challenged the previously existing capture detection systems. For this reason, a Segmented Total Energy Detector (sTED) has been developed to overcome the limitations in the detector's response, by reducing the active volume per module and by using a photo-multiplier (PMT) optimized for high counting rates. This paper presents the main characteristics of the sTED, including energy and time resolution, response to gamma-rays, and provides as well details of the use of the Pulse Height Weighting Technique (PHWT) with this detector. The sTED has been validated to perform neutron-capture cross-section measurements in EAR2 in the neutron energy range from thermal up to at least 400 keV. The detector has already been successfully used in several measurements at n_TOF EAR2.
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