| 1. |
- Walker, Anthony P, et al.
(author)
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Horizon 2020 EuPRAXIA design study
- 2017
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In: Journal of Physics: Conference Series. - : IOP Publishing. - 1742-6588 .- 1742-6596. ; 874:1
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Journal article (peer-reviewed)abstract
- The Horizon 2020 Project EuPRAXIA ("European Plasma Research Accelerator with eXcellence In Applications") is preparing a conceptual design report of a highly compact and cost-effective European facility with multi-GeV electron beams using plasma as the acceleration medium. The accelerator facility will be based on a laser and/or a beam driven plasma acceleration approach and will be used for photon science, high-energy physics (HEP) detector tests, and other applications such as compact X-ray sources for medical imaging or material processing. EuPRAXIA started in November 2015 and will deliver the design report in October 2019. EuPRAXIA aims to be included on the ESFRI roadmap in 2020.
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| 2. |
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| 3. |
- Andreev, N. E., et al.
(author)
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Analysis of laser wakefield dynamics in capillary tubes
- 2010
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In: New Journal of Physics. - : IOP Publishing. - 1367-2630. ; 12
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Journal article (peer-reviewed)abstract
- A general approach to the modifications of the spectrum of a laser pulse interacting with matter is elaborated and used for spectral diagnostics of laser wakefield generation in guiding structures. Analytical predictions of the laser frequency red shift due to the wakefield excited in a capillary waveguide are confirmed by self-consistent modeling results. The role of ionization blue shift, and nonlinear laser pulse and wakefield dynamics on the spectrum modification, is analyzed for recent experiments on plasma wave excitation by an intense laser pulse guided in hydrogen-filled glass capillary tubes up to 8 cm long. The dependence of the spectral frequency shift, measured as a function of filling pressure, capillary tube length and incident laser energy, is in excellent agreement with the simulation results, and the associated longitudinal accelerating field is in the range 1-10 GV m(-1).
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| 4. |
- Athanassiou, N., et al.
(author)
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Simulation of thermal and mechanical performance of laser cladded disc brake rotors
- 2022
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In: Proceedings of the Institution of mechanical engineers. Part J, journal of engineering tribology. - London : SAGE Publications Ltd. - 1350-6501 .- 2041-305X. ; 236:1, s. 3-14
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Journal article (peer-reviewed)abstract
- Disc brakes wear during braking events and release airborne particulates. These particle emissions are currently one of the highest contributors to non-exhaust particle emissions and introduce health hazards as well as environmental contamination. To reduce this problem, wear and corrosion-resistant disc coatings have been implemented on grey cast iron brake disc rotors by using various deposition techniques such as thermal spraying and overlay welding. High thermal gradients during braking introduce risks of flaking off and cracking of thermally sprayed coatings with adhesive bonding to the substrate. Overlay welding by laser cladding offers metallurgical bonding of the coating to the substrate and other benefits that motivate laser cladding as a candidate for the coating of the grey cast iron brake discs. This study aims to investigate the effect of laser cladding on the thermal and thermo-structural performance of the coated grey cast iron brake discs. Therefore, thermal and thermo-stress analysis with COMSOL Multiphysics 5.6 software is performed on braking events of grey cast iron brake discs as non-coated – reference and laser cladding coated with stainless steel welding consumables. The Results demonstrated that surface temperatures were more localised, overall higher in the laser cladded coating with over three times the stresses attained of reference grey cast iron discs. The output of the simulations has been compared by tests found in the literature. Laser cladding presented higher reliability and braking performance, nonetheless requiring the evaluation of its thermal impact on other system components.
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| 5. |
- Barker, Dean, 1977, et al.
(author)
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Pedagogical narrative: Working with technology as student teachers
- 2016
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In: Pedagogical Cases: Digital Technologies in Youth Physical Activity, Physical Education & Sport. - London : Routledge.
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Book chapter (peer-reviewed)abstract
- The objective of this chapter is to provide an illustration of how digital technologies are being experienced/utilised/problematised by physical educators. This chapter introduces two Physical Education Teacher Education (PETE) students working at the University of Gothenburg and focuses on course work conducted by those students within their program. The students received an assignment to choose a particular digital technology, develop their own competence with that technology, and then demonstrate to peers how the technology can be used to facilitate learning related to the Swedish physical education curriculum for upper secondary school. A narrative of their experiences and reflections, developed through written reflections as well as informal conversations with the lead author, is presented in the first section. Three theoretical accounts of the practitioners’ narrative are then put forward. A Deweyan perspective draws attention to the ways that students and their situations are continually transformed in transaction and how digital technologies become implicated in this process. A Foucaultian perspective focuses on the regulating and controlling aspects of technology and highlights the need for care when using digital technologies. An applied Information Technology perspective highlights the ways in which digital technologies may become part of the social practices of physical education. After introducing these perspectives, a broader pedagogical account is offered in which connections between the three perspectives and current physical education scholarship is made. These connections concern: (1) meaning making; (2) student agency and possibilities for student decision making; (3) the effects of technology on lesson content; and (4) students’ digital competence. The chapter is concluded with reflections from the two PETE students.
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| 6. |
- Bergman, Jan, et al.
(author)
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Synthesis of indolocarbazole quinones; potent aryl hydrocarbon receptor ligands
- 2002
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In: Tetrahedron. - 0040-4020 .- 1464-5416. ; 58:7, s. 1443-1452
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Journal article (peer-reviewed)abstract
- Syntheses of indolo[2,3-b]carbazole-6,12-dione and the isomeric indolo[3,2-b]carbazole-6,12-dione, an extremely efficient inducer of the aryl hydrocarbon (Ah) receptor are described. Initial oxidation of the parent indolo[3,2-b]carbazole followed by several different ring-closing strategies produced the latter compound. Entries into syntheses of unsymmetrical 6,12-disubstituted indolo[2,3-b]carbazoles are also described.
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| 7. |
- Brauer, H.E., et al.
(author)
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Na intercalation of VSe2 studied by photoemission and scanning tunneling microscopy
- 1997
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In: Physical Review B Condensed Matter. - 0163-1829 .- 1095-3795. ; 55:15, s. 10022-10026
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Journal article (peer-reviewed)abstract
- In situ Na intercalation of the layered compound VSe2 has been studied with photoemission and scanning tunneling microscopy. Core-level spectroscopy proves that Na deposited in UHV onto the VSe2 surface rapidly intercalates, leaving only small amounts at the surface. The scanning tunneling microscopy measurements show that the intercalated Na is not uniformly distributed between the VSe2 layers, but preferentially in two-dimensional islands. Thus the surface region is divided into intercalated and nonintercalated areas. Hole-like features in the intercalated areas are interpreted as locally missing Na.
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| 8. |
- Carroll, David C., et al.
(author)
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Dynamic control and enhancement of laser-accelerated protons using multiple laser pulses
- 2009
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In: Comptes Rendus. Physique. - : Elsevier BV. - 1631-0705. ; 10:2-3, s. 188-196
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Journal article (peer-reviewed)abstract
- The use of schemes involving multiple laser pulses to enhance and control the properties of beams of protons accelerated in ultra-intense laser irradiation of planar foil targets is discussed. Specifically, the schemes include the use of a second laser pulse to produce and control preplasma expansion of the target to enhance energy coupling to the proton beam; the use of a second laser pulse to drive shock deformation of the target to change the direction of the proton beam; and a scheme involving dual high intensity laser pulses to change the properties of the sheath field, with the aim of modifying the proton energy spectrum. An overview of our recent experimental and theoretical results is given. The overall aim of this work is to determine the extent to which the properties of the sheath-accelerated proton beam can be optically controlled, to enable beam delivery at high repetition rates. To cite this article: D.C. Carroll et al., C. R. Physique 10 (2009). (C) 2009 Academie des sciences. Published by Elsevier Masson SAS. All rights reserved.
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| 9. |
- Coury, M., et al.
(author)
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Influence of laser irradiated spot size on energetic electron injection and proton acceleration in foil targets
- 2012
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In: Applied Physics Letters. - : AIP Publishing. - 0003-6951 .- 1077-3118. ; 100:7
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Journal article (peer-reviewed)abstract
- The influence of irradiated spot size on laser energy coupling to electrons, and subsequently to protons, in the interaction of intense laser pulses with foil targets is investigated experimentally. Proton acceleration is characterized for laser intensities ranging from 2 x 10(18) - 6 x 10(20) W/cm(2), by (1) variation of the laser energy for a fixed irradiated spot size, and (2) by variation of the spot size for a fixed energy. At a given laser pulse intensity, the maximum proton energy is higher under defocus illumination compared to tight focus and the results are explained in terms of geometrical changes to the hot electron injection. (C) 2012 American Institute of Physics. [doi:10.1063/1.3685615]
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| 10. |
- Coury, M., et al.
(author)
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Injection and transport properties of fast electrons in ultraintense laser-solid interactions
- 2013
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In: Physics of Plasmas. - : AIP Publishing. - 1070-664X .- 1089-7674. ; 20:4
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Journal article (peer-reviewed)abstract
- Fast electron injection and transport in solid foils irradiated by sub-picosecond-duration laser pulses with peak intensity equal to 4 x 10(20)W/cm(2) is investigated experimentally and via 3D simulations. The simulations are performed using a hybrid-particle-in-cell (PIC) code for a range of fast electron beam injection conditions, with and without inclusion of self-generated resistive magnetic fields. The resulting fast electron beam transport properties are used in rear-surface plasma expansion calculations to compare with measurements of proton acceleration, as a function of target thickness. An injection half-angle of similar to 50 degrees - 70 degrees is inferred, which is significantly larger than that derived from previous experiments under similar conditions. (C) 2013 American Institute of Physics. [http://dx.doi.org/10.1063/1.4799726]
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