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Development of a heat treatment method to form a duplex microstructure of lower bainite and martensite in AISI 4140 steeClaesson, Erik January 2014 (has links)
Research on bainite and martensite structures has indicated that lower bainite needles have a refining effect on the lath martensitic structure. Lower bainte needles partitions prior austenite grains and will consequently have a refining effect on the subsequent formed lath martensite. Smaller austenite grains will result in smaller lath martensitic packets and blocks and will result in enhanced mechanical properties. In order to create a variation of lower bainte structure in a matrix of martensite, two different heat treating methods were tested. The work was focused towards the formation of lower bainite during isothermal heat treating in molten salt, above and below the MS-temperature. Both un-tempered and tempered samples were analyzed .Two different materials were tested, both were AISI 4140 but with a slightly difference in hardenability. The material provided by Ovako Steel is 326C and 326F the later had a higher hardenability. In order to better distinguish the two structures from each other when studied under a microscope, a variation of etching methods were tested. It was possible to create a variation of lower bainite structures in a matrix of martensite. 326F shows less amount of lower bainite and provides a higher average surface hardness before tempering.
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Građenje halogenidnih kompleksa kobalta(II) u rastopima smeše neorganskih soli i polarnih organskih jedinjenja / Formation of cobalt(II) halide complexes in molten mixtures of inorganic salts with polar organic compoundsMatijević Borko 21 September 2011 (has links)
<p>U ovoj doktorskoj disertaciji proučavano je građenje kompleksa kobalta(II) sa hloridnim i bromidnim jonima u rastopima koji sadrže jednu neorgansku so i jedno organsko jedinjenje i/ili vodu pri različitom sastavu sistema i na različitim temperaturama. Jedan od sistema je amonijum-nitrat – acetamid – voda sastava NH<sub>4</sub>NO<sub>3</sub>∙(2,61-z)CH<sub>3</sub>CONH<sub>2</sub>∙zH<sub>2</sub>O (z = 0,0 1,61 i 2,61), a drugi sistem je amonijum–nitrat – dimetilsulfoksid (DMSO) sastava NH<sub>4</sub>NO<sub>3</sub>∙zDMSO (z = 1 – 6), na različitim temperaturama (35, 45, 55 i 65 <sup>o</sup>C). Cilj ovog istraživanja je bio određivanje stabilnosti kompleksa kobalta koji se grade sa sa halogenidnim jonima i komponentama rastvarača, pronalaženje kvalitativne i kvantitativne zavisnosti konstanti stabilnosti kompleksa kobalta(II) sa halogenidnim jonima od temperature i molskog odnosa komponenti sistema NH<sub>4</sub>NO<sub>3</sub>∙(2,61-z)CH<sub>3</sub>CONH<sub>2</sub>∙zH<sub>2</sub>O odnosno NH<sub>4</sub>NO<sub>3</sub>∙zDMSO, određivanje termodinamičkih parametara koji karakterišu reakcije asocijacije u ovim sistemima.</p> / <p>In this dissertation the complex formation between cobalt(II) and halide ions in the melts consisting of one inorganic salt, an organic compound and/or water has been studied at different temperatures. Two molten salt systems have been investigated: 1) ammonium nitrate-acetamide-water system NH<sub>4</sub>NO<sub>3</sub>∙(2,61-z)CH<sub>3</sub>CONH<sub>2</sub>∙zH<sub>2</sub>O (z = 0.0 1.61 2.61) and 2) ammonium nitratedimethyl sulfoxide NH<sub>4</sub>NO<sub>3</sub>∙zDMSO (z = 1 – 6), at four different temperatures: 35, 45, 55 and 65 <sup>o</sup>C. The purpose of this work was to determine stability of cobalt(II) complexes formed with the halide ions and the components of the solvents, to discribe the qualitative and quantitative relationships between the stability of the complexes and the melt composition, as well as the changes in the cobalt(II) coordination due to a complex formation. Thermodynamic parameters for cobalt(II) – halide association process in these melts were alsodetermined.</p>
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Obrazovanje hloridnih i bromidnih kompleksa kobalta(II) u električki nesimetričnim vodenim rastopima soli / Cobalt(II) chloride and bromide complex formation in electrical unsymmetric aqueous molten saltsVraneš Milan 23 February 2009 (has links)
<p>U ovoj doktorskoj disertaciji proučavano je građenje kompleksa kobalta(II) sa hloridnim i bromidnim jonima u vodenim rastopima tipa xCa(NO3)2·zH<sub>2</sub>O – (1-x)NH<sub>4</sub>NO<sub>3 </sub>pri različitom sastavu soli (x= 0,3 – 0,9), različitom sadržaju vode (z= 2,67 – 6,67) i na različitim temperaturama (45, 55 i 65<sup>o</sup>C).</p><p>Istraživanja su imala za cilj proučavanje reakcije građenja kompleksa kobalta(II) sa hloridnim i bromidnim jonima u vodenim rastopima xCa(NO<sub>3</sub>)<sub>2</sub>·zH<sub>2</sub>O – (1–x)NH<sub>4</sub>NO<sub>3</sub>, uticaja temperature, sastava elektrolita i sadržaja vode na proces kompleksiranja, kao i određivanje termodinamičkih parametara koji karakterišu reakcije asocijacije u ovim sistemima. Ovakvi rastopi soli su posebno interesantni zbog svoje niske tačke topljenja i visoke latentne toplote topljenja pa se mogu koristiti kao fazno-promenljivi materijali za skladištenje toplotne energije.</p> / <p>In this thesis absorption spectra of cobalt(II) chloride and bromide in calcium nitrate – ammonium nitrate – water system of the composition xCa(NO<sub>3</sub>)<sub>2</sub>·zH<sub>2</sub>O – (1–x)NH<sub>4</sub>NO<sub>3 </sub>(x= 0.30 - 0.90 and z= 2.67 – 6.67) have been investigated in the wavelength range 400-800 nm at three different temperatures: 45, 55 and 65<sup>o</sup>C.</p><p>Temparature, composition of the melt and water content influence on complex formation reactions between cobalt(II) and halide ions in aqueous xCa(NO<sub>3</sub>)<sub>2</sub>·zH<sub>2</sub>O –<br />(1–x)NH<sub>4</sub>NO<sub>3</sub> melts have been studied. Thermodynamic parameters for cobalt(II) – halide association process in different solvents also were determined.</p><p>Investigated systems are interesting because of their high values of latent heat of fusion and low melting points. Due to these reasons, some melts are proposed for <br />heat energy storage materials, usually known as phase change materials (PCM).</p>
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Investigation of Charge Transfer Kinetics in Non–Aqueous Electrolytes Using Voltammetric Techniques and Mathematical ModelingShen, Dai 28 January 2020 (has links)
No description available.
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Novel Approach to Design, Optimization, and Application of Thermal Batteries and BeyondYazdani, Aliakbar 03 June 2021 (has links)
No description available.
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溶融塩電気化学プロセスによる緻密質炭素膜の形成 / ヨウユウエン デンキ カガク プロセス ニヨル チミツシツ タンソマク ノ ケイセイ湯川 晃宏, Akihiro Yukawa 22 March 2014 (has links)
本研究では比較的安価な設備を用い、低温で量産性のある炭素膜を得ることが出来る溶融塩電気化学プロセスに着目し、電解条件が炭素膜に及ぼす影響、浴温が炭素膜に及ぼす影響、基材前処理における酸活性が炭素膜と基材の密着性に及ぼす影響等を明らかにしたものである。 / 博士(工学) / Doctor of Philosophy in Engineering / 同志社大学 / Doshisha University
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Development of an integrated tool to design, estimate cost and calculate annual performances of a solar power tower / Utveckling av ett verktyg som kan utforma, beräkna kostnaden och beräckna årliga avkastningar på ett smält salt soltornBlampain, Emil January 2018 (has links)
This Master Thesis consisted in realizing a tool able to design, estimate the cost and calculate annual yields of a molten salt solar power tower. Such tool was made for a company providing CSP equipment and plant solutions for engineering, engineering and procurement or also EPC of a solar power tower. The Company wishes to propose competitive plant configurations presenting a good trade-off between cost and revenues. The Company can oversee the EPC of a whole power plant or/and supply some components of the molten salt cycle and of the water/steam cycle. The tool models a large scale solar power tower with a thermal energy storage system on EBSILON®Professional 12.04, a thermodynamic software. When launching a simulation, the tool sizes the components of the molten salt cycle (design phase) according to user’s inputs, the other components have their characteristics based on a reference project. Depending on the size of the components, the total cost is determined and the revenues over a year of operation are calculated (annual performance). When performing several simulations with different configurations, the Company can judge about the economic viability of plant configurations by comparing their LCOEs and NPVs. The present document describes the result of the Master Thesis, that is to say the tool itself, what it contains and how it works. The methodology adopted to design the components is presented in depth, the way costs were calculated is exposed. The document explains the annual performance calculations and the simple operation strategy implemented. Finally, a technical and cost validation was carried out but it would require some further work to be complete. The design and cost calculations are performed in few seconds, the annual calculations take around 2-3h. One main contribution of the Master Thesis is to show that designing, estimating costs and calculating annual performances is feasible in a single tool operating at a high level of detail. Using the tool during a solar power tower project could considerably facilitate the current process in place at the Company. It can also allow to compare an important number of configurations to determine a good techno-economic solution. / Denna uppsats bestod i att genomföra ett verktyg som kan utforma, beräkna kostnaden och beräkna årliga avkastningar på ett smält salt soltorn. Ett sådant verktyg gjordes för ett företag inom soltornsteknik, upphandling och konstruktion (SUK) som vill föreslå konkurrenskraftiga anläggningskonfigurationer som presenterar en bra avvägning mellan kostnad och intäkter. Företaget, samtidigt som det övervakar SUK för en hel kraftverk, levererar det också vissa komponenter i den smälta saltcykeln. Verktyget modellerar ett storskaligt soltorn med ett värmeenergilagringssystem på EBSILON®Professional 12.04, en termodynamisk programvara. När en simulering startas, ritar verktyget komponenterna i den smälta saltcykeln (designfas) enligt användarens inmatningar, de andra komponenterna är baserade på ett referensprojekt. Beroende på komponenternas storlek bestäms den totala kostnaden och intäkterna över ett verksamhetsår beräknas (årlig prestation). När flera simuleringar görs med olika konfigurationer kan företaget bedöma sin ekonomiska lönsamhet genom att jämföra sina LCOE och NPV. Det här dokumentet beskriver resultatet av masterprojektet, det vill säga själva verktyget, vad det innehåller och hur det fungerar. Den metod som antagits för att designa komponenterna presenteras grundligt samt hur kostnaderna beräknades. Dokumentet förklarar de årliga prestationsberäkningarna och den enkla operationsstrategin som implementerats. Slutligen genomfördes en teknisk och kostnadsvalidering, men det skulle kräva ytterligare insats för att göra arbetet fullständigt. Konstruktionen och kostnadsberäkningarna utförs på få sekunder, de årliga beräkningarna tar cirka 2-3 timmar. Ett huvudbidrag av examensarbetet är att visa att utformning, uppskattning av kostnader och beräkning av årliga prestanda är möjlig i ett enda verktyg som arbetar på en detaljrik nivå. Att använda verktyget under ett soltornsprojekt kan betydligt underlätta den nuvarande processen på plats hos företaget. Det kan också göra det möjligt att jämföra ett viktigt antal konfigurationer för att bestämma en bra tekno-ekonomisk lösning.
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End-of-life wind blade recycling through thermal processBenz, Kerstin January 2023 (has links)
Renewable energy production with wind turbines has been rising in the last 30 years and it is a crucial technology, which is necessary for the energy transition. As sustainable as the energy production of wind turbines is, the waste management of the blade material is not. Most of the blades end up on a landfill or get incinerated. There are different types of recycling methods, but the most commonly used is to shred the fibers into little pieces and reusing them for filler material in the concrete industry. This approach does not actually split up the blade material into its components but it is more of a downcycling. In this thesis, a new type of pyrolysis will be looked into, which splits up the blade material into its components namely glass fibers and plastic using molten salt. This process would make the glass fiber industry more sustainable by introducing a recycled glass fiber with minimal loss in quality. In a first step, the blade material will be examined more closely with a thermogravimetric analysis to find out what kind of plastic it is and what temperature would be necessary to pyrolyze it. This information will be used to conduct an experiment in a molten salt solution and determine the necessary reaction time and temperature. This data will be used to compare the costs of this method with shredding the material and the conventional pyrolysis. From the thermogravimetric analysis, it was possible to determine that the type of plastic used in this turbine was made out of epoxy. The maximum degredation of this material occurred at 380 ◦C. Not many experiments could be conducted in order to find the optimal conditions for the pyrolysis process due to difficulties with the furnace. Nevertheless, one sample was successfully pyrolyzed at a temperature of 400 ◦C with a residence time of 15 minutes. With the current market conditions in the recycled glass fibers industry, this product would be too expensive and the demand would be too little. However, the market is expected to grow in the next couple years due to rising interests in circular economy and governments introducing regulations. Nevertheless, it is necessary to increase the efficiency of the molten salt pyrolysis in order to be applicable to a bigger scale. More experiments should be conducted with cheaper molten salt in order to sink the costs of the process.
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In-Situ Chlorine Gas Generation for Chlorination and Purification of Rare Earth and Actinide MetalsSchvaneveldt, Mark H 01 August 2022 (has links)
Rare earth and actinide metals, critical to security, medicine, and the economy, have been processed through methods such as solvent extraction and electrorefining. To minimize radiological waste and improve yield, a 'chloride volatility' process--also known as the chlorination and volatilization process (CVP)--has been proposed and demonstrated for processing rare earths. The process takes advantage of the low vapor pressure of rare earth chlorides (<700 >°C), CaCl2 was added to LaCl3 to lower the melting temperature. LaCl3 electrochemical behavior has not previously been studied in CaCl2. Cyclic voltammetry (CV) and square wave voltammetry (SWV) were applied to LaCl3 salts in CaCl2-LiCl and CaCl2 to study the metal ion behavior. Various electrode materials were compared at low CV scan rates (s-1) to determine compatibility with chlorine gas evolution. Experiments of eutectic LaCl3-CaCl2 were performed and analyzed to determine the efficacy of chlorine gas generation via electrolysis for the CVP. Through galvanostatic electrolysis, oxidation of chloride ions and subsequent chlorination of rare earth was demonstrated, with cerium chosen as the representative rare earth metal. Through a quadrupole mass spectrometer plumbed in line with the electrolytic cell, the quality of the generated gas was analyzed.
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Integrated Study of Rare Earth Drawdown by Electrolysis for Molten Salt RecycleWu, Evan January 2017 (has links)
No description available.
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