| 1. |
- Brachmann, Cole, 1993, et al.
(författare)
-
Herbivore-shrub interactions influence ecosystem respiration and biogenic volatile organic compound composition in the subarctic
- 2023
-
Ingår i: Biogeosciences. - 1726-4170 .- 1726-4189. ; 20, s. 4069-4086
-
Tidskriftsartikel (refereegranskat)abstract
- Arctic ecosystems are warming nearly 4 times faster than the global average, which is resulting in plant community shifts and subsequent changes in biogeochemical processes such as gaseous fluxes. Additionally, herbivores shape plant communities and thereby may alter the magnitude and composition of ecosystem respiration and biogenic volatile organic compound (BVOC) emissions. Here we determine the effect of large mammalian herbivores on ecosystem respiration and BVOC emissions in two southern and two northern sites in Swedish Scandes, encompassing mountain birch (LOMB) and shrub heath (LORI) communities in the south and low-herb meadow (RIGA) and shrub heath (RIRI) communities in the north. Herbivory significantly altered BVOC composition between sites and decreased ecosystem respiration at RIGA. The difference in graminoid cover was found to have a large effect on ecosystem respiration between sites as RIGA, with the highest cover, had 35 % higher emissions than the next highest-emitting site (LOMB). Additionally, LOMB had the highest emissions of terpenes, with the northern sites having significantly lower emissions. Differences between sites were primarily due to differences in exclosure effects and soil temperature and the prevalence of different shrub growth forms. Our results suggest that herbivory has a significant effect on trace gas fluxes in a productive meadow community and that differences between communities may be driven by differences in shrub composition. Copyright:
|
|
| 2. |
- Börjesson Sandén, Fredrik, 1995, et al.
(författare)
-
Effects of boric acid on volatile tellurium in severe accident conditions
- 2024
-
Ingår i: Annals of Nuclear Energy. - 0306-4549 .- 1873-2100. ; 200
-
Tidskriftsartikel (refereegranskat)abstract
- Boric acid is used in light-water nuclear reactors to control the reactor and is expected to be present as part of the chemistry of a severe accident. Therefore, its influence on other prominent species expected in an accident must be investigated. One such species is tellurium. In the present study, tellurium is volatized, and boric acid is dissolved and injected into the system as a means of studying the interaction between it and tellurium. The experiments were evaluated with ICP-MS and XPS. Results suggest that while there is no direct interaction, boric acid still affects the tendency for tellurium to oxidize. In general, less oxidation was detected in the presence of boric acid than in its absence, especially at high temperatures. The species formed upon oxidation was determined to be TeO2. Since tellurium metal is more volatile than TeO2, this may have implication in a wider severe accident context.
|
|
| 3. |
- Espegren, Fredrik, 1989, et al.
(författare)
-
Tellurium transport in the RCS under conditions relevant for severe nuclear accidents
- 2021
-
Ingår i: Progress in Nuclear Energy. - : Elsevier BV. - 0149-1970. ; 139
-
Tidskriftsartikel (refereegranskat)abstract
- In the case of a severe nuclear power plant accident, tellurium is one of the more problematic and volatile fission products. If released it could become a health issue as it decays to iodine which accumulates in the thyroid gland. Research exists, that indicates tellurium likely interacts with caesium under severe accident conditions, thus it is important to further explore related phenomenon. In this work, tellurium was exposed to high temperature under oxidizing and inert conditions simulating severe accident conditions with and without airborne caesium iodide to determine the effect on the tellurium source term. The effect of caesium iodide was noticeable on tellurium transport behaviour in the gas phase under oxidizing and inert conditions. Under humid oxidizing conditions with caesium iodide, no significant impact on the total aerosol mass transport was noticed. However, less tellurium was transported through the model primary circuit and a potentially new compound was observed on the filter located after this model. Comparing inert dry to humid with caesium iodide showed an increase in the total aerosol mass transport whereas there was a decrease noticed of the tellurium reaching the filter after the model primary circuit. In the latter case, new unidentified compound(s) correlated to caesium, iodine and tellurium were observed on the filter located after the model. In this work, evidence was found that tellurium behaviour will be affected by caesium iodide under the investigated conditions. Moreover, it seems that under inert conditions the formed compounds may be stable at close to ambient temperatures. Unlike under oxidizing conditions, where dissociation likely occurred.
|
|
| 4. |
|
|
| 5. |
- Karkela, T., et al.
(författare)
-
Tellurium retention by containment spray system
- 2021
-
Ingår i: Annals of Nuclear Energy. - : Elsevier BV. - 0306-4549 .- 1873-2100. ; 164
-
Tidskriftsartikel (refereegranskat)abstract
- A containment spray system is used to mitigate the source term from the containment building to the environment as part of the severe accident management actions. Tellurium is one of the volatile fission products and many of the tellurium isotopes decay into iodine, which causes a threat to the public due to its radiotoxicity and build-up in the thyroid gland. The removal efficiency of the containment spray system model against tellurium species formed under severe accident conditions was investigated with experiments and MELCOR simulations. The results indicated efficient removal of tellurium aerosols in the air atmosphere, whereas a decrease in the efficiency was observed in the nitrogen atmosphere. Gaseous tellurium species were not formed in significant amounts during the experiments and therefore, the removal efficiency due to different spray chemistry conditions could not be accurately analysed. However, the alkaline chemicals used in the spray solution seemed to form airborne particles, increasing the overall aerosol transport in the process independently of CsI or Te aerosol transport.
|
|
| 6. |
|
|
| 7. |
- Kučera, Jan, et al.
(författare)
-
Tellurium determination by three modes of instrumental neutron activation analysis in aerosol filters and trap solutions for the simulation of a severe nuclear accident
- 2020
-
Ingår i: Microchemical Journal. - : Elsevier BV. - 0026-265X. ; 158
-
Tidskriftsartikel (refereegranskat)abstract
- Tellurium belongs to the elements not frequently determined by neutron activation analysis (NAA) or other analytical methods. We present results of a new methodological study using three independent modes of instrumental NAA (INAA) using the 123mTe, 131Te and 131I radionuclides. We compare the results obtained in terms of accuracy, precision and limits of detection (LOD). We utilized the INAA procedures tested for the tellurium determination in aerosol filters and trap solutions in a model experiment aimed at reducing the knowledge gap concerning the behaviour of 132Te, a radiologically significant fission product, which constitutes a considerable health risk towards the public in case of its release in a severe nuclear power plant accident. We found that the nuclear reaction 130Te(n,γ)131Te and gamma-ray spectrometric measurement of 131I, a descendant of 131Te, is the most sensitive way of Te determination by INAA providing as low LOD values as 0.15 µg of Te in the Teflon aerosol filters and 0.22 µg mL-1 in the 0.1 M NaOH trap solutions. The three independent INAA modes allowed employing the self-verification principle of INAA for increasing the trustworthiness of our results. Finally, we also point to the indispensable role of the non-destructive feature of INAA for assay of samples, such as Teflon aerosol filters, that are difficult to be analysed by other analytical methods requiring complete sample destruction without analyte losses.
|
|
| 8. |
- Lysenkova Wiklander, Mariya, et al.
(författare)
-
Genomic, transcriptomic and epigenomic sequencing data of the B-cell leukemia cell line REH
- 2023
-
Ingår i: BMC Research Notes. - : BioMed Central (BMC). - 1756-0500. ; 16:1
-
Tidskriftsartikel (refereegranskat)abstract
- ObjectivesThe aim of this data paper is to describe a collection of 33 genomic, transcriptomic and epigenomic sequencing datasets of the B-cell acute lymphoblastic leukemia (ALL) cell line REH. REH is one of the most frequently used cell lines for functional studies of pediatric ALL, and these data provide a multi-faceted characterization of its molecular features. The datasets described herein, generated with short- and long-read sequencing technologies, can both provide insights into the complex aberrant karyotype of REH, and be used as reference datasets for sequencing data quality assessment or for methods development.Data descriptionThis paper describes 33 datasets corresponding to 867 gigabases of raw sequencing data generated from the REH cell line. These datasets include five different approaches for whole genome sequencing (WGS) on four sequencing platforms, two RNA sequencing (RNA-seq) techniques on two different sequencing platforms, DNA methylation sequencing, and single-cell ATAC-sequencing.
|
|
| 9. |
- Millkrantz, Jens
(författare)
-
Petrokultur och energihistoria
- 2022
-
Ingår i: Scandia. - 0036-5483. ; 88:1
-
Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
|
|
| 10. |
- Millkrantz, Jens, 1989, et al.
(författare)
-
Petrokultur och energihistoria
- 2022
-
Ingår i: Scandia. - : Scandia: Tidskrift for historisk forskning, Lund University. - 2002-4339 .- 0036-5483. ; 88:1, s. 127-140
-
Forskningsöversikt (refereegranskat)abstract
- Trots dess helt avgörande roll för det moderna samhällets uppkomst och utveckling har oljan varit förvånansvärt frånvarande i historisk forskning, med vissa undantag för specifikt energihistorisk forskning. Samtidigt har oljan och oljerelaterade idéer och praktiker tagit allt större plats inom andra humanistiska discipliner, såsom miljö- och energihumaniora. I denna översiktsartikel introducerar vi den forskning från dessa fält som samlats under begreppet petrokulturer (petrocultures).
|
|
