| 1. |
- Insulander Björk, Klara L, 1982, et al.
(författare)
-
Irradiation testing of enhanced uranium oxide fuels
- 2019
-
Ingår i: Annals of Nuclear Energy. - : Elsevier BV. - 0306-4549 .- 1873-2100. ; 125, s. 99-106
-
Tidskriftsartikel (refereegranskat)abstract
- Enhanced uranium oxide fuel types are being tested in the Halden Research Reactor in Norway with the aim is to assess the effect that these enhancements have on fuel performance. Fuel temperatures, rod pressures and dimensional changes are being monitored online and an extensive post-irradiation examination programme is planned. Preliminary data show that fuel centerline temperatures can be lowered by addition of ThO2 to the fuel matrix, or by incorporating Cr or SiO2-TiO2 as a network structure within the fuel. In parallel, two types of cladding coatings are tested in order to investigate their in-core properties. No abnormal behaviour has been noted during the first 100 days of irradiation.
|
|
| 2. |
- Insulander Björk, Klara L, 1982, et al.
(författare)
-
Study of Thorium-Plutonium Fuel for Possible Operating Cycle Extension in PWRs
- 2013
-
Ingår i: Science and Technology of Nuclear Installations. - : Hindawi Limited. - 1687-6075 .- 1687-6083. ; 2013
-
Tidskriftsartikel (refereegranskat)abstract
- Computer simulations have been carried out to investigate thepossibility of extending operating cycle length in the PressurisedWater Reactor Ringhals 3 by the use of thorium-plutonium oxidefuel. The calculations have been carried out using tools andmethods that are normally employed for reload design and safetyevaluation in Ringhals 3. The 3-batch reload scheme and the powerlevel have been kept unchanged, and a normal uranium oxide fuelassembly designed for a 12-month operating cycle in this reactoris used as a reference. The use of plutonium as the fissile component reduces the worth ofcontrol rods and soluble boron, which makes it necessary to modifythe control systems. The delayed neutron fraction is low comparedwith the reference, but simulations and qualitative assessments ofrelevant transients indicate that the reactor could still beoperated safely. Differences in reactivity coefficients are mainlybeneficial for the outcome of transient simulations for thethorium based fuel. A 50% extension of the current 12-month operating cycle length should be possible with thorium-plutonium mixed oxide fuel, given an upgrade of the control systems. More detailed simulations have to be carried out for some transients in order to confirm the qualitative reasoning presented.
|
|
| 3. |
- Jansson, Ronnie, et al.
(författare)
-
Functionalized silk assembled from a recombinant spider silk fusion protein (Z-4RepCT) produced in the methylotrophic yeast Pichia pastoris
- 2016
-
Ingår i: Biotechnology Journal. - : Wiley-VCH Verlagsgesellschaft. - 1860-6768 .- 1860-7314. ; 11:5, s. 687-699
-
Tidskriftsartikel (refereegranskat)abstract
- Functional biological materials are a growing research area with potential applicability in medicine and biotechnology. Using genetic engineering, the possibility to introduce additional functions into spider silk-based materials has been realized. Recently, a recombinant spider silk fusion protein, Z-4RepCT, was produced intracellularly in Escherichia coli and could after purification self-assemble into silk-like fibers with ability to bind antibodies via the IgG-binding Z domain. In this study, the use of the methylotrophic yeast Pichia pastoris for production of Z-4RepCT has been investigated. Temperature, pH and production time were influencing the amount of soluble Z-4RepCT retrieved from the extracellular fraction. Purification of secreted Z-4RepCT resulted in a mixture of full-length and degraded silk proteins that failed to self-assemble into fibers. A position in the C-terminal domain of 4RepCT was identified as being subjected to proteolytic cleavage by proteases in the Pichia culture supernatant. Moreover, the C-terminal domain was subjected to glycosylation during production in P. pastoris. These observed alterations of the CT domain are suggested to contribute to the failure in fiber assembly. As alternative approach, Z-4RepCT retrieved from the intracellular fraction, which was less degraded, was used and shown to retain ability to assemble into silk-like fibers after enzymatic deglycosylation.
|
|
