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The most expensive component in a conventional solar photovoltaic (PV) system is the solar module cell. The module cost could be reduced if low-cost reflector materials are used to concentrate solar energy flux across a small module area. Three reflector materials were studied for fill-factor improvements in low concentrating system. These were anodized aluminium, rolled aluminium foil and miro re

The Kruppel-like protein ZNF224 is a co-factor of the Wilms' tumor 1 protein, WT1. We have previously shown that ZNF224 exerts a specific proapoptotic role in chronic myelogenous leukemia (CML) K562 cells and contributes to cytosine arabinoside-induced apoptosis, by modulating WT1-dependent transcription of apoptotic genes. Here we demonstrate that ZNF224 gene expression is down-regulated both in

One problem in concentrating photovoltaic systems without active cooling is the formation of hot spots on the solar module cells. These hotspots are a result of uneven concentration of radiation within the solar module cells. The overall effect of concentrated heating is the reduction in the fill-factor of the solar module cell and the subsequent decrease in the overall efficiency of the system. I

The basic concept of a Net Zero Energy Building (Net ZEB) is that on-site renewable energy generation covers the annual energy load. The main objective of this study is to analyse the increase of embodied energy compared to the decrease of the energy use related to building operation; partly by a literature review, partly by detailed analysis of eleven case studies; taking the step from a low ener

A concentrating photovoltaic wall element, including Cu(In, Ga)Se-2-based modules, aluminum reflectors, and an insulation for building integration, has been developed and evaluated. The geometric concentration ratio of the system is about 3 x. However, the measured maximum electric power from the modules is only 1.9 times that of identical vertical modules without reflectors, due to optical losses

Anthropogenic climate change is one of the most severe environmental challenges facing the planet today, and it is certainly one of the most debated. The built environment is a known major culprit, and cities as consumption centers account for a large share of the world’s consumption-based carbon footprint. It may well be argued that urban communities are at the very core of the climate change pro

We show that glycoside hydrolases can catalyse the synthesis of glycosyl acrylate monomers using renewable hemicellulose as glycosyl donor, and we also demonstrate the preparation of novel glycopolymers by radical polymerisation of these monomers. For this, two family 5 β-mannanases (TrMan5A from Trichoderma reesei and AnMan5B from Aspergillus niger) were evaluated for transglycosylation capacity

Detta arbete avgränsas till att behandla energianvändning i småhus. Studien omfattar tre småhus som byggts för utställningen Bo92 i Örebro. Syftet med studien är att beräkna och ta fram kunskaper om den totala energiåtgången under en byggnads hela livscykel. Användningstiden för husen är antagen till 50 år.This report deals with single-unit dwellings built in 1991 and 1992 in a city called Orebro, Sweden.The houses are prefabricated and the frameworks are made of wood. The aim of the essay is to present the total use of energy during the life-cycle of single-unit dwellings, taking their mode of construction into account. The life-cycle of a house is divided into the following periods: production (m

In this paper we investigate the impact of different memory configurations on performance and energy consumption of the video encoding applications, MPEG-4 and H.264. The memory architecture is integrated with SIMD extended embedded processor, proposed in our previous work. We explore both dedicated memories and multilevel cache-architectures and perform exhaustive simulations. The simulations hav

Hemicelluloses constitute one of the most abundant renewable resources on earth. To increase their utilization, the isolation of hemicelluloses from industrial biomass side-streams would be beneficial. A method was investigated to isolate hemicelluloses from process water from a thermomechanical pulp mill. The method consists of three steps: removal of solids by microfiltration, preconcentration o

The conversion of sodium lactate to lactic acid with water-splitting electrodialysis was investigated. One way of reducing the power consumption is to add a conductive layer to the acid compartment. Doing this reduced the power consumption by almost 50% in a two-compartment cell, whereas the electric current efficiency was not affected at all. Three different solutions were treated in the electrod

Carbon fibre fabrics are electrically conductive and therefore possess the prerequisites for being inductively heated. In-situ heating by induction could significantly reduce processing time and energy consumption during consolidation of carbon fibre composites, but to control the induction heating process properly the electrical conductivity of the fabric must be known. The work presented in this

Freshwater scarcity is a vital societal challenge related to climate change, population pressure, and agricultural and industrial demands. Therefore, sustainable desalination/purification of salty/contaminated water for human uses is particularly relevant. Membrane distillation is an emerging hybrid thermal-membrane technology with the potential to overcome the drawbacks of conventional desalinati

We use first-principle density functional theory (DFT) to predict properties for semicrystalline polyvinyl fluoride (PVF) and compare with polyvinylidiene fluoride. We note that the crystalline regions of PVF are complex in the sense that we lack a complete experimental characterization of the detailed atomic organization. We therefore turn to DFT to predict both the structure and associated mater

The European Union has committed to achieving climate neutrality by the year 2050, with Sweden setting an even more ambitious target of reaching this milestone by 2045. A subgroup comprising 23 pioneering Swedish municipalities, collectively representing 40% of the country's population, aims to attain climate neutrality by 2030. Globally, buildings and construction sector contribute nearly 40% of

Sweden passed legislation to achieve a target of net zero greenhouse gas emissions by the end of 2045. The Energy Performance of Building Directive further obliged European countries to ensure zero-energy building codes and improve the quality of indoor environments when buildings are renovated, as approximately 40% of total greenhouse gas emissions in Sweden are produced while heating buildings.

Bostads- och servicesektorn i Sverige står idag för ungefär 40% av Sveriges totalaårliga energibehov (Energimyndigheten, 2021). Förutom detta används en stormängd energi för nyproduktion, underhåll och rivning av byggnader. Att minskaenergianvändningen i byggsektorns hela livscykel är en nyckel för att nå uppsattaenergi- och klimatmål. I detta projekt analyseras vad som är bäst ur ettenergiperspek

This paper investigates whether executive boards consider firm-specific inefficiencies when they change CEOs in the Swedish electricity distribution sector. Firm-level inefficiencies are calculated using data from all Swedish electricity distributors from 2001 to 2022 and a data envelopment analysis (DEA) approach. DEA has advantages over standard financial key performance indicators since it cont