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The specific heat of a material is simply the measure of the amount of energy required to raise the temperature of a unit mass of the material by one degree. The specific heat of a material depends on the structure, pressure, and temperature of the material. Hence, measurement of specific heat can indicate structural changes and transitions in the material.Previous work at the State University of New York at Buffalo, shored anomalies in the specific heats of Glassy Carbon samples which had been exposed to neutron irradiation. Neutron irradiation of the carbon introduced defects in the material and the specific heat was dependent on the time of sample irradiation. The specific heat plotted as a function of temperature showed peaks at temperatures below 2.0°K. This indicates some kind of transition in the material. Also the specific heat values, which were measured up to 4.5°K, were much lower than the specific heat of the original nonirradiated material. Measurements indicated that the two kinds of samples had the same specific heat at room temperature. This kind of change in the specific heat of carbon has not been explained.The purpose of this project was to investigate the specific heats of these samples above 4.50K to determine where and how the anomalies in the specific heat disappeared at higher temperatures. The specific heats were measured by cooling the sample with liquid helium. This enabled the sample to obtain temperatures of 2.5°K and up. The specific heat was measured by electrically heating the thermally isolated sample and measuring the change in its temperature with a germanium resistance thermometer.

Thermal expansion in a crystal may be completely described from a phenomenological point of view by a second rank tensor whose elements are defined by λ_ij=(∂l_ij/∂T)_σ Or ε_ij=(∂e_ij/∂T)_σ Where the l_ij and the e_ij are the elements of the linear Lagrangian and Eulerian strain tensors respectively. These λ_ij and ε_ij have been formulated in terms of crystal cell parameters. For example, for a monoclinic crystal the λ_ij are of the form: λ₁₁(T) = 1/a₀sinβ₀ d[a(T)sinβ(T)]/dT , λ₁₃(T) = ½ (1/a₀sinβ₀ d[a(T)cosβ(T)]/dT - cotβ₀/c₀ dc(T)/dT) , λ₂₂(T) = 1/b₀ db(T)/DT , and λ₃₃(T) = 1/c₀ dc(T)/dT where a₀, b₀, c₀, and β₀ are the crystal’s cell parameters at some reference temperature T₀. By expressing the crystal cell parameters as power series expansions in the temperature, thermal expansion coefficients have been computed for indialite (hexagonal cordierite), emerald and beryl and for the clinopyroxenes: diopside, hedenbergite, jadeite, ureyite, acmite, and spodumene. The extended Grüneisen equation has been used to further examine the nature of the thermal expansion in emerald, beryl, and diopside. The crystal structures of the synthetic clinopyroxenes CaCoSi₂O₆ (cobalt diopside) and CaNiSi₂O₆ (nickel diopside) have also been determined. / Doctor of Philosophy

As a result of climate change and urbanization, rising temperatures are causing increasing concern about extreme heat in cities worldwide. Urban extreme heat like other climate-related phenomena is a complex problem that requires expertise from a range of disciplines and multi-faceted solutions. Therefore, this study aims to develop a comprehensive understanding of urban heat issue by taking a multi-level approach that integrates science, technology, and policy. Throughout the three main papers of this dissertation, a variety of quantitative and qualitative methods, such as microclimate modeling, machine learning, statistical analysis, and policy content analysis, are used to analyze urban heat from different perspectives. The first paper of this dissertation focuses on the street canyon scale, aiming to identify the physical and vegetation parameters that have the greatest impact on changing thermal conditions in urban environments and to understand how these parameters interact with each other. Moving towards identifying applicable heat-related data and measurement techniques, the second paper assesses whether lower-resolution temperature data and novel sources of vulnerability indicators can effectively explain intra-urban heat variations. Lastly, the third paper of this dissertation reviews heat-related plans and policies at the Planning Districts level in Virginia, providing insights into how extreme heat is framed and addressed at the regional and local levels. This analysis is particularly important for states such as Virginia, which historically have not experienced multiple days of extreme heat during summers, as is common in southern and southwestern states of the United States. The results of this study provide insights into the contributing and mitigating factors associated with extreme heat exposure, novel heat-related data and measurement techniques, and the types of analysis and information that should be included in local climate-related plans to better address extreme heat. This dissertation explores new avenues for measuring, understanding, and planning extreme heat in cities, thereby contributing to the advancement of knowledge in this field. / Doctor of Philosophy / Due to climate change and fast city growth, temperatures are rising, and extreme heat is becoming a big worry in cities worldwide. Urban extreme heat is a challenging problem that needs expertise from different majors and diverse solutions. This dissertation aims to understand urban heat better by integrating science, technology, and policy. The three main research papers of this dissertation use various methods like modeling, statistics, and policy analysis to study urban heat from different angles. The first paper focuses on city streets and how certain physical features and vegetation affect citizens' thermal comfort. The second paper explores new ways to measure heat in urban areas, including using new sources of data and the application of lower-resolution data. Finally, the third paper reviews heat-related plans and policies in Virginia, helping us understand how extreme heat is addressed in areas that might not be accustomed to high temperatures. This dissertation's findings provide useful insights into why the severity of extreme heat is not the same in different parts of cities, present new ways to measure this difference and find solutions to lessen the negative impacts of exposure to heat. It also shows what information needs to be included in plans and policies to better deal with extreme hot weather at the local level such as in towns and cities. By exploring new ways to understand and handle extreme heat in cities, this research helps make progress in this important field. The goal of this research is to help cities prepare for and cope with urban extreme heat, keeping people safe and creating sustainable cities for the future.

Examensarbetet utförs under sista årets energiingenjörsstudier vid Mälardalens högskola. Med hjälp av Ramböll Västerås utfördes en energiuppföljning av energiförbrukningen vid Hälleborgs äldreboende beläget på Bäckby i Västerås åt Västerås stad. Hälleborgs äldreboende stod klart och var fullt inflyttat våren 2015. Boendet byggdes för att möta det ökade behovet av vårdplatser i Västerås kommun. Vid byggnationen ställde kommunen ett byggkrav på 60 kWh/(m2,år) köpt energi vilket var hårdare än de gällande byggkraven som gällde i Sverige vid dåvarande tidpunkt. Under projekteringen av byggnaden ändrades kravet till 70 kWh/(m2,år) viktad energi där fjärrvärmen viktas med 1 och elen med 2.  Ändringen uppkom efter att behovet av kyla kunde lösas med ett borrhålslager vilket ger möjlighet att ta tillvara på värmen som kyls bort via värmepumpar. Byggnadens värmebehov tillgodoses av både värmepumpar och fjärrvärme vilket innebär olika energikrav enligt BBR, viktningen görs för att få ett mellanting mellan kraven för byggnad med el uppvärmning och byggnad utan eluppvärmning. Examensarbetet går ut på att utreda om byggnadens energianvändning går att följa upp efter ett år i drift. Genom att försöka beräkna förbrukningen och på den vägen upptäcka problem som behöver åtgärdas till 2 årsuppföljning 2017. Det har under arbetets gång visat sig att anläggningens mätsystem inte fungerar som tänkt vad det gäller överföring mellan fastighetens mätssystem och Västerås stads mätdata hanteringssystem Momentum. Men även när mätdatainformationen skulle hämtas manuellt visades sig att det endast fanns för ett fåtal datum vilket gjorde det omöjligt att ställa upp en årsenergi. För att kontrollera att mätningen fungerade som det skulle ställdes en sammanställning upp för perioden 2015-02-22 och 2016-03-24 vilket visade att all elproduktion inte registreras i de interna mätarna. Fjärrvärmen var enda energienhet som kunde verifieras då den förbrukningen hämtades från fjärrvärmeleverantören Mälarenergi AB. Fjärrvärmeförbrukningen uppgick till 29 kWh/ kWh/(m2,år) mot projekterade 11.7 kWh/ kWh/(m2,år). För att kunna utföra en korrekt energiuppföljning och visa tappvarmvatten förbrukningen behöver fastigheten uppdateras med fler mätare. Dels behövs en mätare som mäter levererad fjärrvärmeenergi till tappvarmvattnet och det rekommenderas även att registrera en flödesmätare på tappvarmvattnet till verksamheten. Det bör även undersökas vilka elförbrukningar som inte omfattas av internmätning för att kunna skilja verksamhets- och fastighetsenergi åt. Elenergin för undermätarna var 555 406 kWh för perioden 2015-02-22 och 2016-03-24 och motsvarnade 924 025 kWh för nätägaren Mälarenergi i perioden 2015-05-01 till 2016-04-30. För att kunna utföra en balans ska undermätarna uppgå till samma förbrukning som huvudmätaren för samma mät period. Byggnaden uppfyller idag inte förutsättningar för att kunna göra en korrekt energiuppföljning. / In order to reach the 20/20 goals (meaning 20% lower energy consumption until 2020) the energy requirements on buildings must get tougher and tougher. The city of Västerås has from year 2011 set its own energy requirements on all sold estates to 60 kWh/(m2,year). When the city needed to build the new Hälleborgs elderly care center, their aim was to reach this limited energy consumption. Soon, during the planning stage, they changed this requirement to 70 kWh/(m2,year) weighted energy. The reason for this was because they were using two heating systems, one was a electric heat pump and the second was district heating. Because of higher average age in the society, the need for more elderly care centers arise even in Västerås. In the spring 2015 Hälleborgs elderly care center was completed and occupied. 2 year after the building was complete, the contractor has to do an energy monitoring and see if the goal 70 kWh/m2 is reached. In this bachelor thesis all information will be tested and the aim is to try to make a energy monitoring and figure out what needs to be done to be able to performe the energy monitoring 2017. During the work the biggest problem has been to get the right information. The system that should keep all the measured data (Momentum) was found not to have the connection to the building. When we try to pick the data by hand from the building it was not complete. So the conclusion is that the building is not ready to energy monitoring jet. This is because the building needs more time to be stable and adjust the technical systems. It also needs more points of energy measurments and flowmeters in order to get the heating water consumption. In the electric system first the net owners energy meter is installed, then the building has own meters at each electric central to separate customers consumption from building consumption. When groups of energy is summarized, it is just half of the net owners consumption. This is because some of the energy in the building is not registered. One of the electric energy’s that not is registered is the commercial kitchen, but the difference is to big that it need to be evaluated what’s missed.

This diploma thesis deals with the operation of radiators. It is divided into three parts. The first part describes the various types of radiators and heating surfaces, radiator control and heat measurement, the second part deals with the design of heating and hot water in an apartment building in Brno in two variants of the conceptual solution and the third part is processed in the form of experimental measurements issues of radiator operation during a real day in the heating season and operating conditions that may occur.