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Linnaeus University

1. Johansson, Wilhelm. Optical active thin films on cover glass increasing the efficiency of photovoltaic modules.

Degree: Built Environment and Energy Technology, 2018, Linnaeus University

URL: http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-75044 

Thin film coatings of ZnO, TiO2, CeOX and BiOX have been deposited on soda lime silica glass through spray pyrolysis. The effects on the optical properties of the coated glass, as well as the possible impacts on the life expectancy and energy efficiency of PV-modules have been studied. ZnO and TiO2 coatings both reduced the transmission of UV radiation of wavelengths destructive to PV-modules. Therefore, both have the potential to increase the life expectancy of PV-modules if used on cover glass. The ZnO thin film also showed an increase in photoluminescence at 377 nm when radiated with UV radiation of 325 nm while TiO2 reduced the photoluminescence. ZnO coatings on the cover glass have the potential to increase the efficiency of PV-modules in addition to UV protection. No CeOX or BiOX films were found to be deposited with the method used. The ZnO and TiO2 coated samples showed a decrease in transmission of light, due to increased reflection and possibly scattering. This needs to be addressed if these kinds of coatings are going to be beneficial for Si PV-modules.

Subjects/Keywords: Thin films; Coatings; Metal oxides; UV-protection; UV-cutoff; Optical bandgap; Renewable Energy; Photoluminescence; PV-modules; Energy Efficiency; Life expectancy; Tunnfilm; metalloxider; UV-skydd; UV-kant; Optiskt bandgap; Förnyelsebar Energi; Fotoluminiscens; Solcellsmoduler; Solceller; Verkningsgrad; Teknisk Livslängd; Energy Engineering; Energiteknik

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Johansson, W. (2018). Optical active thin films on cover glass increasing the efficiency of photovoltaic modules. (Thesis). Linnaeus University. Retrieved from http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-75044

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Johansson, Wilhelm. “Optical active thin films on cover glass increasing the efficiency of photovoltaic modules.” 2018. Thesis, Linnaeus University. Accessed January 17, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-75044.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Johansson, Wilhelm. “Optical active thin films on cover glass increasing the efficiency of photovoltaic modules.” 2018. Web. 17 Jan 2021.

Vancouver:

Johansson W. Optical active thin films on cover glass increasing the efficiency of photovoltaic modules. [Internet] [Thesis]. Linnaeus University; 2018. [cited 2021 Jan 17]. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-75044.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Johansson W. Optical active thin films on cover glass increasing the efficiency of photovoltaic modules. [Thesis]. Linnaeus University; 2018. Available from: http://urn.kb.se/resolve?urn=urn:nbn:se:lnu:diva-75044

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

2. Chatwin-Davies, Aidan. A Covariant Natural Ultraviolet Cutoff in Inflationary Cosmology.

Degree: 2013, University of Waterloo

URL: http://hdl.handle.net/10012/7759 

In the field of quantum gravity, it is widely expected that some form of a minimum length scale, or ultraviolet cutoff, exists in nature. Recently, a new natural ultraviolet cutoff that is fully covariant was proposed. In the literature, most studies of ultraviolet cutoffs are concerned with Lorentz-violating ultraviolet cutoffs. The difficulty in making a minimum length cutoff covariant is rooted in the fact that any given length scale can be further Lorentz contracted. It was shown that this problem is avoided by the proposed covariant cutoff by allowing field modes with arbitrarily small wavelengths to still exist, albeit with exceedingly small, covariantly-determined bandwidths. In other words, the degrees of freedom of sub-Planckian modes in time are highly suppressed. The effects of this covariant ultraviolet cutoff on the kinematics of a scalar quantum field are well understood. There is much to learn, however, about the effects on a field’s dynamics. These effects are of great interest, as their presence may have direct observational consequences in cosmology. As such, this covariant ultraviolet cutoff offers the tantalizing prospect of experimental access to physics at the Planck scale. In cosmology, the energy scales that are probed by measurements of cosmic microwave background (CMB) statistics are the closest that we can get to the Planck scale. In particular, the statistics of the CMB encodes information about the quantum fluctuations of the scalar inflaton field. A measure of the strength of a field’s quantum fluctuations is in turn given by the magnitude of the field’s Feynman propagator. To this end, in this thesis I study how this covariant ultraviolet cutoff modifies the Feynman propagator of a scalar quantum field. In this work, I first calculate the cutoff Feynman propagator for a scalar field in flat spacetime, and then I address the cutoff Feynman propagator of a scalar field in curved spacetime. My studies culminate with an explicit calculation for the case of a power-law Friedmann-Lemaître-Robertson-Walker (FLRW) spacetime. This last calculation is cosmologically significant, as power-law FLRW spacetime is a prototypical and realistic model for early-universe inflation. In preparation for studying the covariant cutoff on curved spacetime, I will review the necessary back- ground material as well as the kinematic influence of the covariant cutoff. I will also discuss several side results that I have obtained on scalar quantum field theories in spacetimes which possess a finite start time.

Subjects/Keywords: theoretical physics; mathematical physics; cosmology; quantum field theory; quantum gravity; Planck scale effects; trans-Planckian; UV cutoff

…length scale, or natural ultraviolet (UV) cutoff, exists in nature at the order of… …a fully covariant UV cutoff was proposed in [9, 10]. The proposed cutoff is a… …consequences in cosmology. As such, this covariant UV cutoff offers the tantalizing prospect of… …evidence of the proposed covariant UV cutoff in the CMB, one should understand the effect that… …is to study how the proposed covariant UV cutoff modifies the Feynman propagator of a… 

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APA · Chicago · MLA · Vancouver · CSE | Export to Zotero / EndNote / Reference Manager

APA (6th Edition):

Chatwin-Davies, A. (2013). A Covariant Natural Ultraviolet Cutoff in Inflationary Cosmology. (Thesis). University of Waterloo. Retrieved from http://hdl.handle.net/10012/7759

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Chicago Manual of Style (16th Edition):

Chatwin-Davies, Aidan. “A Covariant Natural Ultraviolet Cutoff in Inflationary Cosmology.” 2013. Thesis, University of Waterloo. Accessed January 17, 2021. http://hdl.handle.net/10012/7759.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

MLA Handbook (7th Edition):

Chatwin-Davies, Aidan. “A Covariant Natural Ultraviolet Cutoff in Inflationary Cosmology.” 2013. Web. 17 Jan 2021.

Vancouver:

Chatwin-Davies A. A Covariant Natural Ultraviolet Cutoff in Inflationary Cosmology. [Internet] [Thesis]. University of Waterloo; 2013. [cited 2021 Jan 17]. Available from: http://hdl.handle.net/10012/7759.

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

Council of Science Editors:

Chatwin-Davies A. A Covariant Natural Ultraviolet Cutoff in Inflationary Cosmology. [Thesis]. University of Waterloo; 2013. Available from: http://hdl.handle.net/10012/7759

Note: this citation may be lacking information needed for this citation format:
Not specified: Masters Thesis or Doctoral Dissertation

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