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Discovery-Oriented Screening of Dynamic Systems: Combinatorial and Synthetic ApplicationsAngelin, Marcus January 2010 (has links)
This thesis is divided into six parts, all centered around the development of dynamic (i.e., reversibly interacting) systems of molecules and their applications in dynamic combinatorial chemistry (DCC) and organic synthesis. Part one offers a general introduction, as well as a more detailed description of DCC, being the central concept of this thesis. Part two explores the potential of the nitroaldol reaction as a tool for constructing dynamic systems, employing benzaldehyde derivatives and nitroalkanes. This reaction is then applied in part three where a dynamic nitroaldol system is resolved by lipase-catalyzed transacylation, selecting two out of 16 components. In part four, reaction and crystallization driven DCC protocols are developed and demonstrated. The discovery of unexpected crystalline properties of certain pyridine β-nitroalcohols is used to resolve a dynamic system and further expanded into asynthetic procedure. Furthermore, a previously unexplored tandem nitroaldol-iminolactone rearrangement reaction between 2-cyanobenzaldehyde and primarynitroalkanes is used for the resolution of dynamic systems. It is also coupled with diastereoselective crystallization to demonstrate the possibility to combine several selection processes. The mechanism of this reaction is investigated and a synthetic protocol is developed for asymmetric synthesis of 3-substituted isoindolinones. Part five continues the exploration of tandem reactions by combining dynamic hemithioacetal or cyanohydrin formation with intramolecular cyclization to synthesize a wide range of 3-functionalized phthalides. Finally, part six deals with the construction of a laboratory experiment to facilitate the introduction of DCC in undergraduate chemistry education. The experiment is based on previous work in our group and features an acetylcholinesterase-catalyzed resolution of a dynamic transthioacylation system. / QC 20100628
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Normal Mapping för Hårda Ytor : Photoshop och Maya Transfer Maps för Normal Mapping av icke-organiska geometri i datorspel / Normal Mapping for Hard Surfaces : Photoshop and Maya Transfer Maps for Normal Mapping of non-organic geometry in computer gamesFors, Martin January 2009 (has links)
I mitt examensarbete har jag undersökt om det lämpar sig att använda en manuell metod för att skapa normal maps till icke-organiska polygonmodeller avsedda för datorspel. Jag har använt mig av Photoshop för att måla normal maps som jag sedan applicerar på lågdetaljerade modeller jag skapat, för att höja detaljgraden avsevärt. Då icke-organisk modellering inbegriper modeller som ska representera hårda ytor, och därmed inte animeras med deformation, så antog jag att denna metod skulle lämpa sig väldigt väl åt dessa ytor som ofta har extremt mjuka former och precisa vassare kanter. Min metod har varit att studera litteratur om Normal Mapping och hur man använder Photoshop för detta. Jag har sedan utfört praktiskt arbete för att utvärdera hur effektiv metoden är samt vilka fördelar den bidrar med. Jag går igenom teori för normal mapping som jag stödjer med hjälp av faktatexter och instruktions-DVDer i ämnet för att sedan redovisa metoden jag använt i mitt arbete. Jag avslutar sedan med en diskussion kring mitt resultat och redovisar vad jag kommit fram till genom mina experiment. Jag kommer fram till att Normal Mapping med Photoshop är mycket väl lämpat åt hårda ytor och även bidrar med optimeringar i arbetsflödet både vad gäller organisering, tidsåtgång samt kontroll över resultatet. Ytterligare så ges förslag på förbättringar i pluginets funktionalitet för att öka användarvänligheten.
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Ny teknik för småskalig kraftvärme : - med fokus på Organisk RankineCykel (ORC)Eriksson, Åsa January 2009 (has links)
As a part of the fight against the global warming the energy production needs to be more efficient and redirected towards sustainable options. One alternative is cogeneration, which means that electricity and heat is produced in one plant. The purpose with this survey is to examine if there are any commercial available combined heat and power techniques, based on combustion of solid moist biomass, which are suitable to small-scale applications. The technique must be able to produce between 2 and 10 MW thermal and the heat demand is a Swedish district-heating system. When already published reports had been studied, the Organic Rankine Cycle (ORC) was chosen as the most suitable technique. The possibility of using the ORC to generate electricity from the district-heating return flow was considered simultaneously. The chosen ORC-technique was then evaluated in Excel. The first aspect to be examined was how the performance of a combined heat and power plant was affected by variations in the supply line temperature. It showed that the performance reaches top levels when the temperature is low. The second part contains an optimisation, in a techno-economical perspective, of the ratio between cogeneration and separate heat production for district-heating systems with heat demands below 50 GWh/year. The most profitable combined heat and power plant generates 45 % of the installed power in a 50 GWh system. The profit is, however, too low to justify any construction plans. The conclusion was that there are no economical reasons to choose combined heat and power based on an organic rankine cycle in Sweden today.
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Normal Mapping för Hårda Ytor : Photoshop och Maya Transfer Maps för Normal Mapping av icke-organiska geometri i datorspel / Normal Mapping for Hard Surfaces : Photoshop and Maya Transfer Maps for Normal Mapping of non-organic geometry in computer gamesFors, Martin January 2009 (has links)
<p><p>I mitt examensarbete har jag undersökt om det lämpar sig att använda en manuell metod för att skapa normal maps till icke-organiska polygonmodeller avsedda för datorspel. Jag har använt mig av Photoshop för att måla normal maps som jag sedan applicerar på lågdetaljerade modeller jag skapat, för att höja detaljgraden avsevärt.</p><p> </p><p>Då icke-organisk modellering inbegriper modeller som ska representera hårda ytor, och därmed inte animeras med deformation, så antog jag att denna metod skulle lämpa sig väldigt väl åt dessa ytor som ofta har extremt mjuka former och precisa vassare kanter.</p><p> </p><p>Min metod har varit att studera litteratur om Normal Mapping och hur man använder Photoshop för detta. Jag har sedan utfört praktiskt arbete för att utvärdera hur effektiv metoden är samt vilka fördelar den bidrar med. Jag går igenom teori för normal mapping som jag stödjer med hjälp av faktatexter och instruktions-DVDer i ämnet för att sedan redovisa metoden jag använt i mitt arbete. Jag avslutar sedan med en diskussion kring mitt resultat och redovisar vad jag kommit fram till genom mina experiment.</p><p> </p><p>Jag kommer fram till att Normal Mapping med Photoshop är mycket väl lämpat åt hårda ytor och även bidrar med optimeringar i arbetsflödet både vad gäller organisering, tidsåtgång samt kontroll över resultatet. Ytterligare så ges förslag på förbättringar i pluginets funktionalitet för att öka användarvänligheten.</p></p>
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Diaryliodonium Salts : Development of Synthetic Methodologies and α-Arylation of EnolatesBielawski, Marcin January 2011 (has links)
This thesis describes novel reaction protocols for the synthesis of diaryliodonium salts and also provides an insight to the mechanism of α-arylation of carbonyl compounds with diaryliodonium salts. The first chapter gives a general introduction to the field of hypervalent iodine chemistry, mainly focusing on recent developments and applications of diaryliodonium salts. Chapter two describes the synthesis of electron-rich to electron-poor diaryliodonium triflates, in moderate to excellent yields from a range of arenes and iodoarenes. In chapter three, it is described that molecular iodine can be used together with arenes in a direct one-pot, three-step synthesis of symmetric diaryliodonium triflates. A large scale synthesis of bis(4-tert-butylphenyl)iodonium triflate is also described, controlled and verified by an external research group, further demonstrating the reliability of this methodology. The fourth chapter describes the development of a sequential one-pot synthesis of diaryliodonium salts from aryl iodides and boronic acids, furnishing symmetric and unsymmetric, electron-rich to electron-poor diaryliodonium tetrafluoroborates in moderate to excellent yields. This method was developed to overcome the regiochemical limitations imposed by the reaction mechanism in the protocols described in the preceding chapters. Chapter five describes a one-pot synthesis of heteroaromatic iodonium salts under similar conditions described in chapter two. The final chapter describes the reaction of enolates with chiral diaryliodonium salts or together with a phase transfer catalyst yielding racemic products. DFT calculations were performed, which revealed a low lying energy transition state (TS) between intermediates, which is believed to be responsible for the lack of selectivity observed in the experimental work. It is also proposed that a [2,3] rearrangement is preferred over a [1,2] rearrangement in the α-arylation of carbonyl compounds. The synthetic methodology described in this thesis is the most generally applicable, efficient and high-yielding to date for the synthesis of diaryliodonium salts, making these reagents readily available for various applications in synthesis.
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Asymmetric transformation of ß- and γ-functionalized alcohols : Study of combined ruthenium-catalyzed racemization and enzymatic resolutionTräff, Annika January 2011 (has links)
The major part of this thesis describes the asymmetric synthesis of β- and γ-amino alcohols through the combination of ruthenium catalyzed racemization and enzymatic kinetic resolution. The dynamic kinetic resolution, DKR, protocol for chlorohydrins was improved by employing Bäckvall’s catalyst, which is a base activated racemization catalyst, in combination with Burkholderia cepacia lipase. These optimized conditions broadened the substrate scope and improved the yields and ee’s of the obtained chlorohydrin acetates. The utility of the method was demonstrated in the synthesis of (S)-salbutamol. In the second part of the thesis, DKR was utilized in the enantio-determining step of the total synthesis of (R)-duloxetine. Optimized DKR conditions, combining Bäckvall’s catalyst together with Candida antarctica lipase B, afforded a β-cyano acetate in high yield and ee. (R)-Duloxetine was accessible through synthetic alterations of the enantioenriched β-cyano acetate in high overall yield. A dynamic kinetic asymmetric transformation, DYKAT, protocol to obtain enantio- and diastereomerically pure γ-amino alcohols was developed. In a first step N-Boc-aminoketones were obtained in high enantiomeric purity through a proline-catalyzed Mannich reaction. Subsequent in situ reduction coupled with a highly efficient DYKAT yielded γ-amino acetates in high dr and ee. The γ-amino alcohols were available through simple hydrolysis/deprotection with retained stereochemistry. In the final part of the thesis a heterogeneous bifunctional catalytic system is reported, which combines the catalytic properties of transition metal-catalyzed racemization with enzymatic acylation. A novel ruthenium-phosphonate complex was synthesized and then covalently anchored to the active site of solid supported Candida antarctica lipase B. The partially inhibited beads proved to be catalytically active both in racemization as well as enzymatic acylation. / At the time of the doctoral defense, the following papers were unpublished and had a status as follows: Paper 2: In press. Paper 3: Epub ahead of print.
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Formspråk för en människofokuserad urban gestaltning : Strategier för ökad tillgänglighet till stadens offentliga rumWester, Emelie January 2018 (has links)
Denna uppsatts i fysisk planering undersöker möjligheterna för gestaltningar av urbana offentliga miljöer utifrån ett organiskt människofokuserat perspektiv för att öka tillgängligheten för individer med högkänsliga sinnen till stadens publika miljöer. Det här arbetet fokuserar på sinnesintryckskänsligheten och hur genom detta miljöer som är bättre för alla människor kan skapas, samtidigt som fler funktionsnedsättningars (även neurologiskas) behov kan involveras vid planläggningen av städers miljöer. Arbetet går ut på en kombination av vetenskapliga fysiska urbana planeringsdesignteorier av olika kända teoretiker och kunskaper om hur miljön genom sinnesintrycken påverkar människorna som bor och vistas i den, Där ett stort behov setts av att öka tillgängligheten till offentliga miljöer så att denna involverar individer med starkare sinnensintrycksupptagning som bl.a. är karaktäristiskt för vissa neurologiska funktionsnedsättningar samt på samma gång skapa ett fysiskt planeringsfokus utifrån människan i första hand. Då anpassningar efter idealet från den extremare upplevelsen gör miljön betydligt bättre även för den “normala”(allmänna) upplevaren, Genom enkätundersökningar skapas en bild av hur individer med högre sinnesuppfattning upplever den offentliga urbana miljön och tillsammans med litterär kunskap samt fallstudier skapar detta arbete kunskap i hur dessa miljöer bättre kan utformas efter dessa ideal. Denna kunskap kommer illustreras i bilder och principer i resultatet av denna uppsatts. / This bachelor’s thesis in spatial planning investigates the possible designs of urban public places for an organic humanfocused perspective for an increased accessibility for people with highly sensitive senses to the citys public environments. This work focus on high sensory experience and how through this environments that are better for alla humans can be created, at the same time as more disabilities needs (even neurologicals) gets involved when citys environments gets planed. This work is an combination of spatial plannings urban design teories of known teoretics and knowledge of how the environment through the sensory input affects the people that lives and stay there. Where a big need have been identifyed for increased accessability to public places so that it involves individuals with an higher sensory input as for example is an character of people with some neurological disabilties as on the same time make a fysical planing focus on people firstly. As the costomizations after the ideals of the more extrem experiens will make the environment considerably better even for the “normal”(general) experiencer. Through questionnaires an image is created of how individuals with an higher sensory experince precives the public urban environment and togheter with literary knowledge as well as case studies, do this work create knowledge in how those environments can be designed. This knowledge will be illustrated in pictures and priciples in the results of this paper.
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Ett nytt användningsområde för materialet OrganoComp® : genom en materialdriven designprocess / A New Application For OrganoComp® : through a material-driven design processBerg, Jonatan January 2017 (has links)
Syftet med detta projekt är att med hjälp av en materialinriktad designprocess skapa en produkt av biokompositmaterialet OrganoComp® för att demonstrera dess styrkor och möjligheter. Arbetet kommer att följa metoden ”Material Driven Design (MDD)”, vilket betyder att processen kommer att börja med en noggrann studie av materialet – dels tekniskt och ur ett användarcentrerat perspektiv, men även jämförelsemässigt mot andra material. Insikterna från dessa studier kommer sedan trattas ner och sammanfattas i en ”designintention” som ska sätta målet för designarbetet. Slutligen kommer ett antal koncept som uppfyller designintentionen arbetas fram, varav ett koncept – ett litet, ihopvikbart och nedbrytbart paraply/regnskydd kommer att väljas ut som det slutgiltiga. Paraplyet visar på materialets vattenavvisande egenskaper, i kombination med hårdhet och vikbarhet. Målet med projektet är att skapa en demonstrator som även har potential att bli en användbar produkt i framtiden, och samtidigt ge företaget OrganoClick nya insikter och flera förslag på nya användningsområden för sitt material.
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HIGH LOADED ANAEROBIC MESOPHILIC DIGESTION OF SEWAGE SLUDGE : An evaluation of the critical organic loading rate and hydraulic retention time for the anaerobic digestion process at Käppala Wastewater Treatment Plant (WWTP).Gärdeklint Sylla, Ibrahima Sory January 2020 (has links)
Käppala wastewater treatment plant (WWTP) has, during a few years, observed an increase in organic loading rate (OLR) in the mesophilic anaerobic digester R100, due to an increased load to the WWTP. The digestion of primary sludge at Käppala WWTP is today high loaded, with a high organic loading rate (OLR) and low hydraulic retention time (HRT). This study aims to evaluate the effect of the maximum OLR and the minimum HRT for the anaerobic digestion of sewage sludge and to investigate further actions that can be taken into consideration in case of process problems in the digestion. The study consists of (a) a practical laboratory experiment of 6 pilot-scale reactors to investigate how the process stability is affected when the OLR increases and the HRT decreases. (b) A mass balance calculation based on the energy potential in the feeding sludge and the digested sludge. (c) A study of the filterability of the digested sludge. (d) The construction of a forecasting model in Excel, to predict when digester R100 will reach its maximum OLR and minimum HRT. The result of the study shows that the maximum OLR for Käppala conditions is 4.9 g VS dm-3 d-1, meaning that R100 will reach its maximum organic load around the year 2031. An OLR of 4.5-4.9 and an HRT of 12 days is optimal for R100, according to the present study. Keeping the anaerobic digestion process in balance is vital when it comes to the outcome of energy in the anaerobic digestion process. Pushing the process to produce more gas can become counterproductive since a high OLR can lead to process imbalance, which in turn leads to low biogas production. Imbalance in the digestion process can occur fast; therefore, the margin for overload in the anaerobic digestion process must be significant. The methane concentration in the converted biogas and the pH level in the reactor are the best stability parameters for the conditions at Käppala. Ammonia is the less efficient stability parameter since it did not predict or detect any instability during the experimental process. Furthermore, the OLR and HRT have a significant impact on the needed quantity for dewatering polymer. The higher digestion of organic material in the sludge, the bigger the need for the polymer to take care of the rest material.
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high loaded anaerobic mesophilic digestion of sewage sludge : An evaluation of the critical organic loading rate and hydraulic retention time for the anaerobic digestion process at Käppala Wastewater Treatment Plant (WWTP).Sylla, Ibrahima January 2020 (has links)
Käppala wastewater treatment plant (WWTP) has, during a few years, observed an increase in organic loading rate (OLR) in the mesophilic anaerobic digester R100, due to an increased load to the WWTP. The digestion of primary sludge at Käppala WWTP is today high loaded, with a high organic loading rate (OLR) and low hydraulic retention time (HRT). This study aims to evaluate the effect of the maximum OLR and the minimum HRT for the anaerobic digestion of sewage sludge and to investigate further actions that can be taken into consideration in case of process problems in the digestion. The study consists of (a) a practical laboratory experiment of 6 pilot-scale reactors to investigate how the process stability is affected when the OLR increases and the HRT decreases. (b) A mass balance calculation based on the energy potential in the feeding sludge and the digested sludge. (c) A study of the filterability of the digested sludge. (d) The construction of a forecasting model in Excel, to predict when digester R100 will reach its maximum OLR and minimum HRT. The result of the study shows that the maximum OLR for Käppala conditions is 4.9 g VS dm-3 d-1, meaning that R100 will reach its maximum organic load around the year 2031. An OLR of 4.5-4.9 and an HRT of 12 days is optimal for R100, according to the present study. Keeping the anaerobic digestion process in balance is vital when it comes to the outcome of energy in the anaerobic digestion process. Pushing the process to produce more gas can become counterproductive since a high OLR can lead to process imbalance, which in turn leads to low biogas production. Imbalance in the digestion process can occur fast; therefore, the margin for overload in the anaerobic digestion process must be significant. The methane concentration in the converted biogas and the pH level in the reactor are the best stability parameters for the conditions at Käppala. Ammonia is the less efficient stability parameter since it did not predict or detect any instability during the experimental process. Furthermore, the OLR and HRT have a significant impact on the needed quantity for dewatering polymer. The higher digestion of organic material in the sludge, the bigger the need for the polymer to take care of the rest material.
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