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Popular Abstract in Swedish Dagens samhälle är väldigt beroende av fordon av olika slag. Aldrig förr har människor rest till olika delar av världen, så mycket som idag. Den enorma mängden resors och transporter som sker varje dag är en tung belastning för vår natur. Bilar och lastbilar, som ökar i antal varje dag, släpper ut giftiga avgaser på vägarna och flygplan förbrukar enorma mängder fossilt Urban traffic involves frequent acceleration and deceleration. During deceleration, the energy previously used to accelerate the vehicle is mainly wasted on heat generated by the friction brakes. If this energy that is wasted in traditional internal combustion engines (ICE) could be saved, the fuel economy would improve. Today there are several solutions to meet the demand for better fuel economy

AbstractPhysical exhaustion can constrain human ascending work capacity and performance during emergency evacuation on stairs. The overall aim of this research was to explore and compare stair ascending capacities and physiological limitations during two different strategies: self-preferred pace in three different public stairways in the field, and controlled pace in a laboratory on a stair machin

Most of the experiments related to quantum information applications, involving rare-earth doped inorganic crystals, are performed on yttrium orthosilicate single crystals. The work presented here is motivated by the search of new compounds which can be used in the field of quantum computing and/or quantum storage. Relaxation times and hyperfine structure of the H-3(4)(0)-> D-1(2)(0) transition in

Popular Abstract in Swedish I avhandlingen presenteras delar till radiomottagare med extremt låg effektförbrukning. Detta behövs då dagens samhälle blir allt mer och mer uppkopplat, och detta gäller inte bara persondatorer och mobiltelefoner. Med den snabba teknikutvecklingen inom radiokommunikation, driven av små och smarta mobiltelefoner, går det nu även att få prylar av alla de slag att tala meHistorically, research on radio communication has focused on improving range and data rate. In the last decade, however, there has been an increasing demand for low power and low cost radios that can provide connectivity with small devices around us. They should be able to offer basic connectivity with a power consumption low enough to function extended periods of time on a single battery charge,

The World Trade Organization’s Dispute Settlement Mechanism is exclusively focused on trade; however, there is a potential for it to be utilized to address environmental problems that are also trade distorting. One area where trade and environmental concerns overlap is fossil fuel subsidies. Fossil fuel subsidies support an incumbent energy regime against new renewable alternatives but also benefi

This thesis presents experimental results on the development and optimization of novel and highly compact sources of beams of fast ions, relativistic electrons and coherent x-rays, driven by intense laser-plasma interactions. The rapid development of high-power, short-pulse laser systems have made available peak powers reaching the petawatt regime and focused intensities reaching 10^21 W/cm2. Whe

Hemp milk has the potential to be a climate-friendly substitute for cow milk. In contrast to other milk substitutes, the climate impact of hemp milk has not yet been studied. This study aims to examine the climate impact and water consumption of hemp milk throughout the whole process from the agricultural stage to the finished product via a life cycle assessment. The results show that the climate

Vid avdelningen för kärnfysik utvecklas för närvarande andra generationens Ir-koincidensspektrometer. Anledningen till detta är att det finns ett stort behov bland geologer att mäta spårkvantiteter av Iridium i olika geologiska skikt för att korrelera skiktens ålder med eventuella stora meteoritnedslag. Första generationens spektrometer byggde på en dubbelkoincidens mätt med två HPGe-detektorer, mPresently, the development of the second generation Ir coincidence spectrometer is talking place at the division of Nuclear Physics. There is a large need among geologists to measure trace quantities of Ir in different geological layers and correlate the age of the layer with different large meteorite impacts. The first generation Ir spectrometer was based on a coincidence measured by two HPGe det

This thesis investigates how public archives in Sweden engage with ecological sustainability, with the purpose to provide an opportunity for reflection and discussion on the topic. My point in question is the disambiguation of the Swedish word “hållbarhet”. This is used both in reference to sustainability, meaning actions for improving environmental conditions, and to durability, which in the arch

Microchannels are widely used for heat transfer enhancement. The pressure characteristics are one of the most important factors affecting the heat transfer performance, and the pressure regulation may also control the heat transfer precisely in turn. As a common flow pattern of two-phase flow, slug flow has obvious advantages for heat and mass transfer, like steady flow rate and large interface ar

Qinghai-Tibet Plateau grasslands are unique geographical regions and store substantial soil organic matter (SOM) in the soil surface, which make them very sensitive to global climate change. Here, we focused on three main grassland types (alpine meadow, steppe, and desert) and conducted a soil incubation experiment at five different temperatures (5, 10, 15, 20, and 25°C) to investigate SOM decompo

New durable and hydroxide ion conducting anion-exchange membranes (AEMs) are currently required in order to develop alkaline fuel cells into efficient and clean energy conversion devices. In the present work we have attached quaternary piperidinium (QPi) groups to poly(2,6-dimethyl-1,4-phenylene oxide)s (PPOs) via flexible alkyl spacer chains with the aim to prepare AEMs. The bromine atoms of brom

Solid oxide fuel cells (SOFCs) produce electricity with high electrical efficiency and fuel flexibility without pollution, for example, CO2, NOx, SOx, and particles. Still, numerous issues hindered the large-scale commercialization of fuel cell at a large scale, such as fuel storage, mechanical failure, catalytic degradation, electrode poisoning from fuel and air, for example, lifetime in relation

HIPPIE is a soft X-ray beamline on the 3 GeV electron storage ring of the MAX IV Laboratory, equipped with a novel ambient-pressure X-ray photoelectron spectroscopy (APXPS) instrument. The endstation is dedicated to performing in situ and operando X-ray photoelectron spectroscopy experiments in the presence of a controlled gaseous atmosphere at pressures up to 30 mbar [1 mbar = 100 Pa] as well as

Dion–Jacobson (DJ)-type 2D halide perovskites present superior environmental stability and a narrower bandgap, yet a contradiction between charge transport and stability remains to be resolved. Herein, it is shown that both symmetry and substitution of the organic spacer in DJ perovskites synergistically direct the narrow interlayer spacing, staggered spacer alignment, and regular phase arrangemen

In this work we report the impact of using mid-infrared laser-induced thermal grating spectroscopy (IRLITGS) for temperature measurements in flames by probing hot water lines. The measurements have been performed in the product zone of laminar atmospheric CH 4 /H 2 /air flat flames with equivalence ratio ranging between 0.6 and 1.05. LITGS is a technique based on thermalization through collisions

We describe a series of microcalorimeter X-ray spectrometers designed for a broad suite of measurement applications. The chief advantage of this type of spectrometer is that it can be orders of magnitude more efficient at collecting X-rays than more traditional high-resolution spectrometers that rely on wavelength-dispersive techniques. This advantage is most useful in applications that are tradit