| 1. |
- Jaderstrom, H., et al.
(författare)
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200 and 300 MeV/nucleon nuclear reactions responsible for single-event effects in microelectronics
- 2008
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Ingår i: Physical Review C. Nuclear Physics. - 0556-2813 .- 1089-490X. ; 77:4, s. 44601-
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Tidskriftsartikel (refereegranskat)abstract
- An experimental study of nuclear reactions between Si-28 nuclei at 200 and 300 MeV/nucleon and hydrogen or deuterium target nuclei was performed at the CELSIUS storage ring in Uppsala, Sweden, to collect information about the reactions responsible for single-event effects in microelectronics. Inclusive data on Si-28 fragmentation, as well as data on correlations between recoils and spectator protons or alpha particles are compared to predictions from the Dubna cascade model and the Japan Atomic Energy Research Institute version of the quantum molecular dynamics model. The comparison shows satisfactory agreement for inclusive data except for He fragments where low-energy sub-barrier fragments and recoiling fragments with very large momenta are produced much more frequently than predicted. The yield of exclusive data are also severely underestimated by the models whereas the charge distributions of recoils in these correlations compare well. The observed enhancement in He emission, which may well be important for the description of single-event effects, is most likely to be attributed to alpha clustering in Si-28 nuclei.
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| 2. |
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| 3. |
- Li, Bo, 1968, et al.
(författare)
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Chloride ingress in portland cement concrete under frost action
- 2007
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Ingår i: “5th International Essen Workshop - Transport in Concrete - Nanostructure and Macrostructure”, Essen, June 2007, ed. M J Setzser, Aedificatio Publishers. ; , s. 251-261
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Konferensbidrag (refereegranskat)abstract
- This paper presents the results from the laboratory investigation of chloride ingress in Portland cement concrete under frost action. As a part of doctoral work, six types of Portland cement concrete with w/c from 0.30 to 0.75, five of them with and one without air entraining agent (AEA), were used in the investigation, including the measurements of capillary suction of water and sodium chloride solution with and without frost action, chloride penetration profiles with and without frost action, and scaling and relative ultrasonic pulse transmission time (UPTT) after different freeze-thaw cycles. The results show that none of the six types of concrete revealed any significant sign of external or internal damages after 112 cycles of freeze-thaw, while significant liquid uptakes due to the frost action were found in almost all types of concrete. Consequently, these liquid uptakes accelerated chloride penetration into concrete to some extent.
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| 4. |
- Li, Bo, 1968, et al.
(författare)
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Chloride penetration in concrete exposed under different temperatures
- 2007
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Ingår i: Proceedings of International RILEM Workshop on Integrated Service Life Modelling of Concrete Structures. ; RILEM PRO 56, s. 31-38
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Konferensbidrag (refereegranskat)abstract
- This paper presents the results from the laboratory investigation of chloride penetration in concrete exposed under different temperatures. As a part of doctoral work, six types of Portland cement concrete with w/c from 0.30 to 0.75 and with or without air entrained agent were used in the investigation. The concrete specimens were exposed to 3% NaCl solution under constant temperatures of 20 ºC, 5 ºC and 0 ºC, and daily cyclic temperature regime for freeze-thaw actions. The measurements include liquid uptake and chloride penetration profiles. The results show considerably big differences in chloride penetration profiles obtained after exposure under different temperatures. The results demonstrate again that the freeze-thaw action significantly increases the liquid uptake. This uptaken liquid as a chloride solution increased chloride ingress in concrete.
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| 5. |
- Li, Bo, 1968, et al.
(författare)
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The effects of mineral additions on chloride penetration into concrete under the frost action
- 2008
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Ingår i: Proceedings of IALCCE08 - First International Symposium on Life-Cycle Civil Engineering. - 9780415468572 ; , s. 189-194
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Konferensbidrag (refereegranskat)abstract
- This paper presents the results from a study of the effects of mineral additions on chloride penetration into concrete under the frost action. Mineral additions namely fly-ash (FA), silica fume (SF), GGBF slag (SL) were used to replace some part of cement in concrete. Seven types of concrete were investigated. All specimens were immersed in tap water or NaCl solutions under the freeze-thaw (F-T) and the climate room conditions. The results showed that the frost action significantly increase liquid uptake in both plain Portland cement concrete and concrete with mineral additions whatever specimens were exposed to tap water or salt solutions. Incorporation of mineral additions in concrete can in general reduce the amount of uptaken liquid. As a conclusion, incorporation of mineral additions and proper entraining air pores in concrete can improve resistance of concrete to chloride penetration even under the frost action.
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| 6. |
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| 7. |
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| 8. |
- Luping, Tang, et al.
(författare)
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Kartläggning av armeringskorrosion i betongstommar
- 2005
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Ingår i: Bygg & Teknik. ; :2, s. 25-28
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Tidskriftsartikel (populärvet., debatt m.m.)abstract
- Armeringskorrosion är en av de vanligaste orsakerna till skador på armerade betongstommar som är utsatta för karbonatisering eller kloridhaltig miljö. Ett typiskt exempel är bärande väggelement i vägtunnlar, som ofta exponeras för tösaltad miljö i nordiska länder. För bedömning av betongstommars tillstånd och för planering av erforderligt och kostnadseffektivt underhåll är det nödvändigt att kartlägga förekomst och utbredning av armeringskorrosion genom att använda snabba och enkla metoder med tillfredsställande noggrannhet. En sådan rationell, nyutvecklad teknik publicerades i Bygg & teknik (7/03). I denna artikel presenteras en praktisk tillämpning av denna teknik för kartläggning av armeringskorrosion i betongväggar i Söderledstunneln i Stockholm.
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| 9. |
- Murin, Yu., et al.
(författare)
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A detector system for studying nuclear reactions relevant to Single Event Effects
- 2007
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Ingår i: Nuclear Instruments and Methods in Physics Research Section A. - : Elsevier BV. - 0168-9002 .- 1872-9576 .- 0167-5087. ; 578:2, s. 385-398
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Tidskriftsartikel (refereegranskat)abstract
- We describe a device to study reactions relevant for the Single Event Effect (SEE) in microelectronics by means of 200A and 300AMeV, inverse kinematics, Si + H and Si + D reactions. The work is focused on the possibility to measure Z = 2-14 projectile fragments as efficiently as possible. During commissioning and first experiments the fourth quadrant of the CELSIUS storage ring acted as a spectrometer to register fragments in two planes of Si strip detectors in the angular region 0 degrees-0.6 degrees. A combination of ring-structured and sector-structured Si strip detector planes operated at angles 0.6 degrees-1.1 degrees. For specific event tagging a Si+ phoswich scintillator wall operated in the range 3.9 degrees-11.7 degrees and Si Delta E-E telescopes of CHICSi type operated at large angles.
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| 10. |
- Tang, Luping, 1956, et al.
(författare)
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Assessment of reinforcement corrosion in a concrete highway tunnel
- 2006
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Ingår i: International conference on Concrete Repair, Rehabilitation and Retrofitting (ICCRRR), 21-23 November 2005, Cape Town. - 0415396565 ; , s. 153-154
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Tidskriftsartikel (refereegranskat)abstract
- This paper presents a case study of the assessment of reinforcement corrosion in concrete highwaytunnel structures in Stockholm, Sweden. The tunnel is about 1.6 km long and consists of different types of reinforcedconcrete aged from12 to 40 years. Due to the use of deicing salts, the concrete structures have been subjectedto corrosion damage in different extents. The newly developed rapid technique for corrosion measurement wasemployed for mapping the corrosion of steel in about 120 monoliths of concrete walls along the tunnel. The techniqueinvolves the measurements of corrosion rate, half-cell potential and resistivity of concrete. These threeparameters together supply valuable information about the corrosion extent of reinforcement in concrete. Someconcrete samples were taken for determination of chloride content in order to verify the results from the nondestructivecorrosion mapping. The results show that the measured corrosion rate is in good agreement with thechloride content measurement and the visual observations, while the half-cell potential in many cases is uncertain.Even though the resistivity of concrete alone cannot tell much information about reinforcement corrosion,it indeed helps the judgment of corrosion when together with the measurement of corrosion rate.
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