| 1. |
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| 2. |
- Jonsson, C. E., et al.
(författare)
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High-resolution diatom d18O records from two sub-Arctic high-altitude lakes in the Swedish Scandes
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Ingår i: Journal of Quaternary Science. - 0267-8179 .- 1099-1417.
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Tidskriftsartikel (refereegranskat)abstract
- Waters from high altitude alpine lakes are mainly recharged by meteoric water. Because of seasonal variations in precipitation and temperature, and relatively short hydraulic residence times, most high altitude lakes have lake water isotopic compositions (δ18Olake) that fluctuate due to seasonality in water balance processes. Input from snowmelt, in particular, has a significant role in determining lake water d18O. Here we compare two high resolution δ18Odiatom records from lake sediments in the Swedish Scandes with instrumental data from the last century obtained from nearby meteorological stations. The time period AD 1900 to AD 1990 is characterized by an increase in winter precipitation and high winter/summer precipitation ratios and this is recorded in δ18Odiatom as decreasing trends. Lowest δ18Odiatom values and highest amount of winter precipitation are found around AD 1990 when the winter North Atlantic Oscillation index was above +2. We conclude that for the last 150 years the main factor affecting the δ18Odiatom signal in these sub-Arctic high altitude lakes with short residence times has been changes in amount of winter precipitation and that δ18Odiatom derived from high altitude lakes in the Swedish Scandes can be used as a winter precipitation proxy.
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| 3. |
- Herrlin, K, et al.
(författare)
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Contrast-enhanced radiography by differential absorption, using a laser-produced X-ray source
- 1997
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Ingår i: Investigative Radiology. - 0020-9996. ; 32:5, s. 306-310
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Tidskriftsartikel (refereegranskat)abstract
- RATIONALE AND OBJECTIVES. The authors evaluate the feasibility of differential imaging of contrast media, with division of individual pixel values obtained from digital images generated by characteristic radiation from a laser-produced plasma, bridging the K-absorption edge of the contrast agent. METHODS. Laser pulses from an ultrashort-pulse terawatt laser system were focused onto gadolinium and tantalum targets, creating a plasma from which characteristic radiation and Bremsstrahlung was emitted. The elements of the target were selected so the characteristic emission lines of one of the elements were below the K edge of the contrast agent and the emission lines of the other element above. A phantom with gadolinium and other elements in various concentrations was examined. One radiographic exposure was made using a gadolinium target source and a subsequent exposure using a tantalum source. Both images were recorded digitally and the transmission ratios calculated by division of the individual pixel values. RESULTS. When viewed separately, the two images of the test phantom appeared similar. In the differential image, only the gadolinium solutions were bright, reflecting a difference in attenuation between the two exposures. CONCLUSIONS. Element-specific radiographs can be obtained by differential imaging. When fully explored, the technique may allow for contrast-enhanced radiography with increased sensitivity and decreased contrast dose.
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| 4. |
- Herrlin, K, et al.
(författare)
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Generation of X-rays For Medical Imaging By High-power Lasers - Preliminary-results
- 1993
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Ingår i: Radiology. - 1527-1315. ; 189:1, s. 65-68
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Tidskriftsartikel (refereegranskat)abstract
- PURPOSE: To evaluate the use of x-ray imaging performed with a high-power laser system in biologic and medical studies. MATERIALS AND METHODS: A compact terawatt laser system based on chirped pulse amplification in titanium-doped sapphire was used. X rays were generated by irradiating a high-atomic-number target (tantalum). RESULTS: When photons with an energy below 10 keV were removed with use of 3 mm of aluminum, the half-value layer in aluminum for the remaining x rays was approximately 10 mm. The x-ray source allowed performance of biologic magnification radiography. Star-pattern tests indicated an equivalent focal spot size of less than 60 mum. Exposures of a single pulse could be obtained. The duration of a single x-ray pulse was estimated to be of the order of picoseconds. CONCLUSION. With use of subpicosecond laser pulses, x-ray generation can occur with a smaller equivalent focal spot size than with conventional x-ray sources.
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| 5. |
- Svedman, Cecilia, et al.
(författare)
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Contact allergy to gold in patients with gold-plated intracoronary stents.
- 2005
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Ingår i: Contact Dermatitis. - : Wiley. - 0105-1873 .- 1600-0536. ; 52:4, s. 192-196
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Tidskriftsartikel (refereegranskat)abstract
- An increasingly common and effective method for the treatment of atherosclerotic disease in the coronary arteries is percutaneous transluminal coronary angioplasty (PTCA) and stenting. The stents are made of different metals. An increased rate of restenosis when using gold-plated stents has been shown. Contact allergy to gold is common in many countries. Recently, a study has shown an increased rate of contact allergy to nickel among patients with restenosis and a nickel-containing stent. The aims of our study were to investigate whether there was an increased rate of contact allergy to gold among patients with gold-plated stents and if this increased the risk of restenosis. 22 patients who had received a gold-plated stent were patch tested. An age- and sex-matched population of 88 patients, previously patch tested because of a suspected contact dermatitis, served as controls. In the stent group, 10/22 (45.5%) had a contact allergy to gold, in the control group 18/88 (20.5%); the difference is statistically significant (P = 0.04). There was no significant difference regarding frequency of restenosis. Our study indicates that there is a risk of sensitizing the patient when implanting a gold-plated stent. Further studies are needed to confirm these results and to evaluate whether there is an increased risk of restenosis.
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| 6. |
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| 7. |
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| 8. |
- Brocki, Karin C., et al.
(författare)
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CPT performance, motor activity, and continuous relations to ADHD symptom domains : A developmental study
- 2010
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Ingår i: European Journal of Developmental Psychology. - : Informa UK Limited. - 1740-5629 .- 1740-5610. ; 7:2, s. 178-197
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Tidskriftsartikel (refereegranskat)abstract
- Using a population-based sample consisting of 401 6- to 12-year-olds, this study examined normative age and sex distributions on motor activity as measured in an actigraphic-based motion tracking system (MTS) and on attention-related functions derived from a Continuous Performance Test (CPT). Specific objectives were to present new knowledge on age-related change in motor activity and to study age effects on changes in motor activity and CPT performance as a function of time on task. Further, continuous relations between the two ADHD symptom domains and CPT performance and motor activity, and importantly, age effects in these relations were examined. CPT performance improved, and level of motor activity decreased with age. Linear associations between the two ADHD symptom domains and several of the CPT and MTS parameters support available research describing the nature of ADHD as a continuous dimension with variable expression throughout the general population. Further, our study is one of the first to provide developmental data using a time on task design, particularly with regard to motor activity. Imperative for ADHD future research are our results showing that age matters in the relation between ADHD behaviours and neuropsychological function.
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| 9. |
- Ghisolfi, Selene, et al.
(författare)
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Predicted COVID-19 fatality rates based on age, sex, comorbidities and health system capacity
- 2020
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Ingår i: BMJ Global Health. - : BMJ. - 2059-7908. ; 5:9
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Tidskriftsartikel (refereegranskat)abstract
- Early reports suggest the fatality rate from COVID-19 varies greatly across countries, but non-random testing and incomplete vital registration systems render it impossible to directly estimate the infection fatality rate (IFR) in many low- and middle-income countries. To fill this gap, we estimate the adjustments required to extrapolate estimates of the IFR from high-income to lower-income regions. Accounting for differences in the distribution of age, sex and relevant comorbidities yields substantial differences in the predicted IFR across 21 world regions, ranging from 0.11% in Western Sub-Saharan Africa to 1.07% for high-income Asia Pacific. However, these predictions must be treated as lower bounds in low- and middle-income countries as they are grounded in fatality rates from countries with advanced health systems. To adjust for health system capacity, we incorporate regional differences in the relative odds of infection fatality from childhood respiratory syncytial virus. This adjustment greatly diminishes but does not entirely erase the demography-based advantage predicted in the lowest income settings, with regional estimates of the predicted COVID-19 IFR ranging from 0.37% in Western Sub-Saharan Africa to 1.45% for Eastern Europe.
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| 10. |
- Gratz, M, et al.
(författare)
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X-ray generation for medical applications from a laser-produced plasma
- 1996
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Ingår i: Applied Surface Science. - : Elsevier BV. - 1873-5584 .- 0169-4332. ; 96-8, s. 443-447
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Tidskriftsartikel (refereegranskat)abstract
- We present investigations on the generation of X-ray radiation suitable for different types of medical imaging. Pulses from a 10 Hz terawatt laser system with a duration of 150 fs are focused onto a solid high-Z material target, with focal spot intensities reaching 10(18) W/cm(2). The produced plasma emits broadband X-ray radiation with photon energies up to the MeV region. The application of this X-ray radiation offers new features for medical radiography. Our source allows magnification imaging as well as ultrashort single-shot exposures. New contrast imaging techniques making use of an enhanced characteristic line emission are investigated. The experimental set-up also allows the study of ablation phenomena from sub-picosecond laser pulses by means of particle deposition on thin glass plates. Deposition patterns were studied dependent on different plasma-generation parameters.
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| 11. |
- Gustafsson, Susanne, et al.
(författare)
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Life filming as a means of participatory approach together with older community-dwelling persons regarding their local environment
- 2018
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Ingår i: Scandinavian Journal of Occupational Therapy. - : Taylor & Francis. - 1103-8128 .- 1651-2014. ; 25:5, s. 347-357
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Tidskriftsartikel (refereegranskat)abstract
- Background: The potential to influence the design of one’s local environment is especially important to older people since age-related problems, in combination with a less supportive environment, can prevent the performance of meaningful activities. It is unclear how best to tailor a participatory approach to support the task of collaborating with older persons about their local environment. Life filming was used in such a project. Objective: To describe Life filming as a means of participatory approach in relation to older community-dwelling persons and the design of their local environment. Material and method: A descriptive single case study. Data were generated through field notes and memos, and analyzed utilizing thematic analysis. Participants have validated the findings. Findings: Five themes describe central aspects of Life filming in the given context: Anchoring the concept of participation, Practical application of Life filming, The film as a product, Making a real difference, and An identity as a capable older person. Conclusion: Life filming supported participation, both as a process and an outcome. It had benefits on multiple levels: for the individual person, for older persons as a group, and for the municipality. Life filming could constitute a useful digital tool for practice when a participatory approach is desired.
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| 12. |
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| 13. |
- Jonsson, Christina E., et al.
(författare)
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High-resolution diatom delta O-18 records, from the last 150 years, reflecting changes in amount of winter precipitation in two sub-Arctic high-altitude lakes in the Swedish Scandes
- 2010
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Ingår i: Journal of Quaternary Science. - : Wiley. - 0267-8179 .- 1099-1417. ; 25:6, s. 918-930
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Tidskriftsartikel (refereegranskat)abstract
- Waters from high-altitude alpine lakes are mainly recharged by meteoric water. Because of seasonal variations in precipitation and temperature and relatively short hydraulic residence times, most high-altitude lakes have lake water isotopic compositions (delta O-18(lake)) that fluctuate due to seasonality in water balance processes. Input from snowmelt, in particular, has a significant role in determining lake water delta O-18. Here we compare two high-resolution delta O-18(diatom) records from lake sediments in the Swedish Scandes with instrumental data from the last century obtained from nearby meteorological stations. The time period AD 1900-1990 is characterised by an increase in winter precipitation and high winter/summer precipitation ratios and this is recorded in delta O-18(diatom) as decreasing trends. Lowest delta O-18(diatom) values and highest amount of winter precipitation are found around AD 1990 when the winter North Atlantic Oscillation index was above +2. We conclude that for the last 150 a the main factor affecting the delta O-18(diatom) signal in these sub-Arctic high-altitude lakes with short residence times has been changes in amount of winter precipitation and that delta O-18(diatom) derived from high-altitude lakes in the Swedish Scandes can be used as a winter precipitation proxy.
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| 14. |
- Jonsson, Christina E, et al.
(författare)
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High resolution diatom δ18O records from two sub-Arctic high altitude lakes in the Swedish Scandes
- 2010
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Ingår i: Journal of Quaternary Science. - : Wiley. - 0267-8179 .- 1099-1417. ; 25:6, s. 918-930
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Tidskriftsartikel (refereegranskat)abstract
- Waters from high-altitude alpine lakes are mainly recharged by meteoric water. Because of seasonal variations in precipitation and temperature and relatively short hydraulic residence times, most high-altitude lakes have lake water isotopic compositions (δ18Olake) that fluctuate due to seasonality in water balance processes. Input from snowmelt, in particular, has a significant role in determining lake water δ18O. Here we compare two high-resolution δ18Odiatom records from lake sediments in the Swedish Scandes with instrumental data from the last century obtained from nearby meteorological stations. The time period AD 1900–1990 is characterised by an increase in winter precipitation and high winter/summer precipitation ratios and this is recorded in δ18Odiatom as decreasing trends. Lowest δ18Odiatom values and highest amount of winter precipitation are found around AD 1990 when the winter North Atlantic Oscillation index was above +2. We conclude that for the last 150 a the main factor affecting the δ18Odiatom signal in these sub-Arctic high-altitude lakes with short residence times has been changes in amount of winter precipitation and that δ18Odiatom derived from high-altitude lakes in the Swedish Scandes can be used as a winter precipitation proxy. Copyright © 2010 John Wiley & Sons, Ltd.
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| 15. |
- Kohlweyer, S, et al.
(författare)
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Harmonic generation from solid-vacuum interface irradiated at high laser intensities
- 1995
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Ingår i: Optics Communications. - 0030-4018. ; 117:5-6, s. 431-438
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Tidskriftsartikel (refereegranskat)abstract
- Observations of harmonic generation from solid Al targets irradiated at intensities of 1017 W/cm2 using a tabletop Ti:sapphire terawatt laser system are reported. For irradiances with laser light at a wavelength of [lambda] = 794nm (the fundamental frequency), harmonics up to the 7th, while for irradiances with frequency doubled laser light ([lambda] = 397) nm harmonics up to the 4th of the respective incident radiation were detected.
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| 16. |
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| 17. |
- Nordelöf, Anders, 1975, et al.
(författare)
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A Scalable Life Cycle Inventory of an Electrical Automotive Traction Machine – Technical and Methodological Description
- 2016
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- This report is one of four coupled publications. It describes the technical and methodological selections, and the data collection made to develop of a scalable life cycle inventory (LCI) model of an electrical automotive traction machine. It also presents the essential electrical machine theory background for the work. The report is intended to be used as a reference book for the scalable LCI model when detailed information and explanations are sought. Therefore, no summary or abstract has been included.The scalable LCI model covers both design and production data of a permanent magnet synchronous machine (PMSM). The resulting LCI model, in the form of a Microsoft Excel Macro-Enabled Worksheet file, can be downloaded from the Swedish Life Cycle Center as a part of the SPINE@CPM LCA Database.Furthermore, a series of two peer reviewed articles presents the LCI model based on this report. The first article, part I (DOI: 10.1007/s11367-017-1308-9), describes how the LCI model was established and the type of results it provides, including the underlying PMSM design and the structure of the LCI data model based on mainly chapters 2 and 4 of this report. Additionally to what is included here, it also contains an evaluation of the mass estimations made by the model through comparison with data for seven existing PMSMs for vehicles from established brands, published from 2013 or later.The second article, part II (DOI: 10.1007/s11367-017-1309-8), presents an overview of new primary production data and how literature data was revised to cover the complete PMSM motor manufacturing chain, including magnet fabrication, electrical steel production and a comprehensive survey of an electric motor factory. More in depth information about all production procedures, and how the data was established, is presented in Chapter 5 of this report. Part II of the article series also discusses the selected system boundaries and explains how to link the gate to gate inventory to the Ecoinvent database version 3 (Weidema et al., 2013), based on Chapter 2 of this report.
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| 18. |
- Nordelöf, Anders, 1975, et al.
(författare)
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A scalable life cycle inventory of an electrical automotive traction machine—part I: design and composition
- 2018
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Ingår i: International Journal of Life Cycle Assessment. - : Springer Science and Business Media LLC. - 1614-7502 .- 0948-3349. ; 24:1, s. 55-69
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Tidskriftsartikel (refereegranskat)abstract
- Purpose: A scalable life cycle inventory (LCI) model of a permanent magnet electrical machine, containing both design and production data, has been established. The purpose is to contribute with new and easy-to-use data for LCA of electric vehicles by providing a scalable mass estimation and manufacturing inventory for a typical electrical automotive traction machine. The aim of this article (part I of two publications) is to present the machine design, the model structure, and an evaluation of the models’ mass estimations. Methods: Data for design and production of electrical machines has been compiled from books, scientific papers, benchmarking literature, expert interviews, various specifications, factory records, and a factory site visit. For the design part, one small and one large reference machine were constructed in a software tool, which linked the machines’ maximum ability to deliver torque to the mass of its electromagnetically active parts. Additional data for remaining parts was then gathered separately to make the design complete. The two datasets were combined into one model, which calculates the mass of all motor subparts from an input of maximum power and torque. The range of the model is 20–200 kW and 48–477 Nm. The validity of the model was evaluated through comparison with seven permanent magnet electrical traction machines from established brands. Results and discussion: The LCI model was successfully implemented to calculate the mass content of 20 different materials in the motor. The models’ mass estimations deviate up to 21% from the examples of real motors, which still falls within expectations for a good result, considering a noticeable variability in design, even for the same machine type and similar requirements. The model results form a rough and reasonable median in comparison to the pattern created by all data points. Also, the reference motors were assessed for performance, showing that the electromagnetic efficiency reaches 96–97%. Conclusions: The LCI model relies on thorough design data collection and fundamental electromagnetic theory. The selected design has a high efficiency, and the motor is suitable for electric propulsion of vehicles. Furthermore, the LCI model generates representative mass estimations when compared with recently published data for electrical traction machines. Hence, for permanent magnet-type machines, the LCI model may be used as a generic component estimation for LCA of electric vehicles, when specific data is lacking.
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| 19. |
- Nordelöf, Anders, 1975, et al.
(författare)
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Life cycle assessment of permanent magnet electric traction motors
- 2019
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Ingår i: Transportation Research Part D: Transport and Environment. - : Elsevier BV. - 1361-9209. ; 67, s. 263-274
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Tidskriftsartikel (refereegranskat)abstract
- Ongoing development of electrified road vehicles entails a risk of conflict between resource issues and the reduction of greenhouse gas emissions. In this study, the environmental impact of the core design and magnet material for three electric vehicle traction motors was explored with life cycle assessment (LCA): two permanent magnet synchronous machines with neodymium-dysprosium-iron-boron or samarium-cobalt magnets, and a permanent magnet-assisted synchronous reluctance machine (PM-assisted SynRM) with strontium-ferrite magnets. These combinations of motor types and magnets, although highly relevant for vehicles, are new subjects for LCA. The study included substantial data compilation, machine design and drive-cycle calculations. All motors handle equal take-off, top speed, and driving conditions. The production (except of magnets) and use phases are modeled for two countries – Sweden and the USA – to exemplify the effects of different electricity supply. Impacts on climate change and human toxicity were found to be most important. Complete manufacturing range within 1.7–2.0 g CO2-eq./km for all options. The PM-assisted SynRM has the highest efficiency and lowest emissions of CO2. Copper production is significant for toxicity impacts and effects on human health, with problematic emissions from mining. Resource depletion results are divergent depending on evaluation method, but a sensitivity analysis proved other results to be robust. Key motor design targets are identified: high energy efficiency, slender housings, compact end-windings, segmented laminates to reduce production scrap, and easy disassembly.
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| 20. |
- Svanberg, Sune, et al.
(författare)
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Applications of terawatt lasers
- 1994
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Ingår i: LASER SPECTROSCOPY - XITH INTERNATIONAL CONFERENCE. - : AIP. - 1551-7616 .- 0094-243X. - 1563962624 ; :290, s. 264-269
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Konferensbidrag (refereegranskat)
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| 21. |
- Tillman, Anne-Marie, 1958, et al.
(författare)
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Elmaskiner för fordon i en cirkulär ekonomi. Design för miljö- och resurseffektivitet och krav på End-of-Life system.
- 2020
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Rapport (övrigt vetenskapligt/konstnärligt)abstract
- Elektrifieringen av fordon drivs av nödvändigheten att drastiskt minska klimatutsläppen. Samtidigt behövs mer energi- och materialresurser för att bygga elektriska drivlinor, främst för batterier, men också för också andra komponenter i den elektriska drivlinan, som elmotorer. Föreliggande rapport fokuserar på elmotorer för framdrift av vägfordon, så kallade framdriftsmotorer, och hur de kan anpassas till den cirkulära ekonomin. Material i elmotorerna med väsentlig miljö- och resurspåverkan är aluminium, elektroplåt, koppar samt magnetmaterialen. Deras produktion kräver energi som ger upphov utsläpp av klimatpåverkande gaser. Kopparproduktion leder också till utsläpp av toxiska metaller. Koppar och magnetmetaller som kobolt och sällsynta jordartsmetaller (dit neodym och dysprosium hör) är geologiskt knappa. Gruppen sällsynta jordartsmetaller, liksom kobolt, klassas också som kritiska av EU, vilket betyder att de bedöms utgöra en försörjningsrisk samtidigt som de är ekonomiskt viktiga. Alla materialslagen ger väsentliga bidrag till materialkostnaden. Strategier för att minska resursåtgången kan vara att minimera mängden material, att byta material, att renovera och förlänga motorns livslängd, eller att återvinna motorn till högkvalitativa material. Mer cirkulära materialflöden för elfordon kräver både att fordonen och deras komponenter är utformade för lång livslängd, återanvändning och högkvalitativ återvinning, och att End-of-Life-systemet är anpassat for att effektivt ta hand om uttjänta fordon och deras komponenter och material. Projektet har därför syftat till: - Rekommendationer för design av elektriska framdriftsmotor som uppfyller krav på hög verkningsgrad och annan önskvärd teknisk prestanda, och samtidigt är lämpade för en mer cirkulär ekonomi. - Rekommendationer för utvecklingen av ett End-of-Life-system för fordon som kan nyttiggöra fordonskomponenter designade för en mer cirkulär ekonomi. Nulägesanalyser användes för att välja ett antal motoralternativ att studera, liksom olika alternativ för att hantera dem vid End-of-Life. Kravspecifikationer för studerade motorer upprättades baserat på fordonskrav för en personbil och för en buss. De mest krävande materialen identifierades, utifrån miljöpåverkan, resurstillgång på lång och kort sikt, samt kostnader. Valda motoralternativ varierade med avseende på magnetmaterial, lindningsmaterial och lindningskonfiguration. I några alternativ användes en kärna av pressat järnpulver istället för elektroplåt. Magnetflödets riktning varierade mellan de undersökta motorerna. Demonteringsstudier av använda motorer gav, tillsammans med en kartläggning av dagens End-of-Life-hantering, en beskrivning av hur uttjänta motorer hanteras idag, och utgjorde ett underlag för att ta fram ett scenario för en framtida mer cirkulär hantering med långtgående materialseparation. De utvalda motoralternativen utvärderades med hjälp av elektromagnetiska beräkningar och körscykelberäkningar som användes för att beräkna energianvändningen under drift. Denna användes i livscykelanalyser, tillsammans med data om motorernas sammansättning och produktion, för att utvärdera deras miljö- och resurspåverkan. Effekten av varierande End-of- Life-hantering undersöktes i detalj. Tre möjliga strategier för End-of-Life-systemets utveckling mot resurseffektivitet identifierades: att renovera och öka livslängden hos motorer och deras komponenter; att förbättra materialåtervinningen i dagens system med fragmentering; samt en långt driven separation av material ur motorer som demonterats ur fordonen, för materialåtervinning. Effektiviteten i användning av material och komponenter kan ökas genom renovering och återanvändning. Begränsad renoveringsverksamhet finns idag, främst för tunga fordon, men skulle kunna utökas och också omfatta lätta fordon. Delar som kan bytas ut är kullager, motoraxel och möjligen även hela rotorpaket. Rotorpaket ur kasserade motorer skulle kunna utnyttjas som reservdelar. Hela motorer ur kasserade fordon kan också återanvändas som reservdelar. Däremot är möjligheterna att återanvända magneter mycket begränsade, eftersom deras form är låst till den ursprungliga designen. I befintlig fragmenteringsverksamhet utvecklas kontinuerligt processerna för att sortera material i olika fraktioner. En utmaning för elmaskiner är de hoptrasslade nystan av koppartråd och elektroplåt som uppstår i fragmenteringen, så kallade ”köttbullar”. Separeringen av materialen i dessa skulle kunna drivas längre. Magnetmaterialen hamnar till största delen i en lättfraktion, varifrån de inte återvinns (som magnetmaterial). Inga processlösningar för återvinning av magnetmaterial ur fragmenterat skrot har identifierats. Materialåtervinningen ur framdriftsmotorer kan ökas genom att demontera motorerna ur uttjänta fordon och därefter använda semiautomatiserad separering vilket ger relativt rena materialfraktioner. Det finns utrustning på marknaden för att separera koppar, stål och aluminium från uttjänta elmotorer, En långt driven semiautomatiserad separering av dessa material förbättrar återvinningen jämfört med fragmentering, men endast i begränsad omfattning. Semiautomatiserad separering av motormaterialen är dock den enda identifierade tekniken som gör det möjligt att återvinna magnetmaterial med såpass kvalitet att de kan användas för nytillverkning av magneter. Det finns ingen kommersiell utrustning för att separera ut magneter ur elmotorer inför återvinning idag, men det har gjorts experimentellt, och det finns processlösningar på prototypstadiet. Renovering av framdriftsmotorer kräver att de enkelt kan demonteras ur fordonet och att motorn sedan utan svårigheter kan demonteras till en nivå där delar kan bytas ut. Fixerings- och impregneringsmedel bör därför användas på ett genomtänkt sätt och antalet varianter av skruvar och andra fästanordningar minimeras. Motorns design är avgörande för både dess klimatpåverkan och resursanvändning. Klimatpåverkan orsakas av energianvändningen under drift, som avgörs av verkningsgraden över körcykeln och motorns vikt. Designval med betydelse är valet av lindningsmaterial och lindningskonfiguration. Koppar ger högre energieffektivitet än aluminium, liksom designer med hög andel koppar i det aktiva tvärsnittet, som hårnålslindning eller koncentrerad lindning. De svaga magneter av strontium-ferrit som undersöktes gav låg energianvändning över körcykeln. Strontium-ferritmagneter är dock inte stabila vid temperaturer under cirka 20oC, vilket är en teknisk utmaning som måste lösas. En intressant utvecklingsmöjlighet är att eftersträva elmotorer med hög effekttäthet, till exempel genom att de designas med mer koppar i spåren, kombinerat med svaga magneter. Ett färre antal starka magneter är också en möjlighet. Designer med kärna av pressat järnpulver ger ingen fördel i materialåtervinningen, eftersom dagens fragmenteringsprocesser återvinner koppar, stål och aluminium med tämligen hög effektivitet. Magnetmaterialen återvinns dock inte och inga designåtgärder i elmotor-utvecklingen har identifierats som kan möjliggöra magnetåtervinning i fragmenterings-processen. Däremot, semiautomatiserad demontering av magneter skulle underlättas av en långt driven standardisering av laminatets tvärsnitt, liksom av att magneterna inte limmas fast.
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| 22. |
- Tillman, Carin, et al.
(författare)
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A Longitudinal Examination of the Developmental Executive Function Hierarchy in Children With Externalizing Behavior Problems
- 2015
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Ingår i: Journal of Attention Disorders. - : SAGE Publications. - 1087-0547 .- 1557-1246. ; 19:6, s. 496-506
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Tidskriftsartikel (refereegranskat)abstract
- Objective: Using a 4-year longitudinal design, we evaluated two hypotheses based on developmental executive function (EF) hierarchy accounts in a sample of children with externalizing problems. Method: The participants performed EF tasks when they were between 8 and 12 years (M = 9.93), and again approximately 4 years later when they were between 12 and 15 years (M = 13.36). Results: Inhibition in middle childhood predicted working memory (WM) 4 years later. Further, deficits in inhibition and sustained attention were more prominent in middle rather than late childhood, whereas poor WM was salient throughout these periods. Conclusions: These findings support the hypotheses that EFs develop hierarchically and that EF deficits in ADHD are more prominent in actively developing EFs. They also emphasize ADHD as a developmental disorder.
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| 23. |
- Tillman, C, et al.
(författare)
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Elemental biological imaging by differential absorption with a laser-produced x-ray source
- 1996
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Ingår i: Journal of the Optical Society of America B: Optical Physics. - 0740-3224. ; 13:1, s. 209-215
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Tidskriftsartikel (refereegranskat)abstract
- We demonstrate the novel application of hard x rays emitted by a laser-produced plasma for differential imaging of elements. An x-ray-emitting laser-produced plasma, obtained by the focusing of radiation from a 10-Hz terawatt laser, is used for biological imaging. The x-ray source can be arranged to yield characteristic x-ray emission lines with photon energies that bridge the K absorption edge of a chosen atomic species. One can obtain element-specific radiographs by recording transillumination images for different target materials on digital image plates and by subsequently subtracting or dividing the images. Successful phantom and experimental animal imaging are performed utilizing tantalum and gadolinium as target materials for the terawatt laser and gadolinium as the imaged contrast agent.
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| 24. |
- Tillman, C, et al.
(författare)
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Imaging Using Hard X-rays From A Laser-produced Plasma
- 1995
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Ingår i: Applied Physics B. - 0946-2171. ; 61:4, s. 333-338
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Tidskriftsartikel (refereegranskat)abstract
- Imaging of technical and biological objects using hard X-rays from a laser-produced plasma source is demonstrated. Magnification radiography and single-shot imaging of biological samples are feasible with the source, which utilised focused radiation from a short-pulse terawatt laser. Differential imaging with element specificity and a new projection geometry for X-ray radiography are proposed.
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| 25. |
- Tillman, Carin M., et al.
(författare)
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Motor Response Inhibition and Execution in the Stop-Signal Task : Development and Relation to ADHD Behaviors
- 2008
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Ingår i: Child Neuropsychology. - : Informa UK Limited. - 0929-7049 .- 1744-4136. ; 14:1, s. 42-59
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Tidskriftsartikel (refereegranskat)abstract
- The main aim of this study was to investigate the developmental course of motor response inhibition and execution as measured by the stop-signal task in a population-based sample of 525 4- to 12-year-olds. A further aspiration of the study was to enhance the limited knowledge on how the various stop-signal measures relate to ADHD behaviors in a normal sample. We also wanted to contribute to the theoretical understanding of the various stop-signal measures by examining the relations between the stop-signal measures and performance on tasks reflecting other aspects of response inhibition and execution. Our results showed that the ability to inhibit as well as to execute a motor response as measured by the stop-signal task improved with age during childhood. Of specific interest are the findings suggesting that this task captures the development of motor response inhibition in the late preschool years (age 5 years). Both of the inhibition measures derived from the stop-signal task (i.e., SSRT and probability of inhibition) related significantly to teacher ratings of inattention as well as to performance on tasks tapping other aspects of inhibition. The data provided by this study have thus contributed to the scarce knowledge on early development of motor response inhibition, as well as suggested that the stop-signal task may be a valuable tool for capturing deficient motor response inhibition in ADHD behaviors in normal samples.
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| 26. |
- Tillman, C, et al.
(författare)
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Traumatic fat necrosis: A case report
- 2003
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Ingår i: Acta Dermato-Venereologica. - : Medical Journals Sweden AB. - 1651-2057 .- 0001-5555. ; 83:3, s. 227-228
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Tidskriftsartikel (övrigt vetenskapligt/konstnärligt)
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| 27. |
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