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Chirální separace biologicky aktivních látek v chromatografii / Chiral separation of biologically active compounds by chromatographyLandl, David January 2020 (has links)
- 4 - Abstract in English This diploma thesis is focused on the evaluation and comparison of the enantioselective potential of two columns CHIRAL ART Amylose-SA and CDShell-RSP using a set of 29 chiral drugs in high performance liquid chromatography. The separations of enantiomers were performed in three modes: reversed-phase, normal-phase, and polar- organic mode. The CHIRAL ART Amylose-SA column was tested in normal-phase mode, the CDShell-RSP column in reversed-phase and polar-organic modes. The CHIRAL ART Amylose-SA column contains amylose tris(3,5- dimethylphenylcarbamate) immobilized on 3 µm porous silica gel particles. The CDShell-RSP column contains a chiral selector hydroxypropyl-β-cyclodextrin, which is covalently bonded on 2.7 µm superficially porous particles. In the normal-phase mode, mobile phases composed of hexane and propane-2-ol were used. Furthermore, the effect of various additives (triethylamine, diethylamine, trifluoroacetic acid, and the mixture of diethylamine and trifluoroacetic acid) in the mobile phase on the enantioseparation of chiral drugs was tested. The most universal additive was a mixture of diethylamine and trifluoroacetic acid. A total of 22 chiral drugs were enantioseparated on the CHIRAL ART Amylose-SA column, 10 of them were baseline separated. Mobile phases for...
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Hypersonic Stationary Crossflow Waves: Receptivity to RoughnessVarun Viswanathan (8032571) 04 December 2019 (has links)
<div>Experiments were performed on a sharp-nosed 7° half-angle cone at a 6° angle of attack in the Boeing/AFOSR Mach-6 Quiet Tunnel (BAM6QT) to study the stationary crossflow instability and its receptivity to small surface roughness. Heat transfer measurements were obtained using temperature sensitive paint (TSP) and Schmidt Boelter (SB) heat transfer gauges. Great care was taken to obtain repeatable, quantitative measurements from TSP.</div><div></div><div>Consecutive runs were performed at a 0° angle of attack, and the heat transfer measured by the SB was found to drop as the initial model temperature increased, while other initial conditions such as stagnation pressure were held constant. This agreed with calculations done using a similarity solution. It was found that repeatable measurements at a 6° angle of attack could be made if the initial model temperature was controlled and the patch location that was used to calibrate the TSP was picked in a reasonable and consistent manner.</div><div></div><div>The Rod Insertion Method (RIM) roughness, which was used to excite the stationary crossflow instability, was found to be responsible for the appearance of the streaks that were analyzed. The signal-to-noise ratio in the TSP was too low to properly measure the streaks directly downstream of the roughness insert. The heat transfer along the streak experienced linear growth, peaked, and then slightly decayed. It is possible this peak was saturation. The general trend was that the growth of the streaks moved farther upstream as the roughness element height increased, which agreed with past computations and low speed experiments. The growth of the streak also moved farther upstream as the freestream Reynolds number increased. The amplitude of the streaks was calculated by non-dimensionalizing the heat transfer using the laminar theoretical mean-flow solution for a 7° half-angle cone at a 6° angle of attack. The relationship between the amplitude and the non-dimensional roughness height was approximately linear in the growth region of the streaks.</div>
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Use of Photovoltaic on an E-bike? : A Feasibility StudySchnabel, Thomas January 2013 (has links)
In recent years the number of bicycles with e-motors has been increased steadily. Within the pedelec – bikes where an e-motor supports the pedaling – a special group of transportation bikes has developed. These bikes have storage boxes in addition to the basic parts of a bike. Due to the space available on top of those boxes it is possible to install a PV system to generate electricity which could be used to recharge the battery of the pedelec. Such a system would lead to grid independent charging of the battery and to the possibility of an increased range of motor support. The feasibility of such a PV system is investigated for a three wheeled pedelec delivered by the company BABBOE NORDIC.The measured data of the electricity generation of this mobile system is compared to the possible electricity generation of a stationary system.To measure the consumption of the pedelec different tracks are covered, and the energy which is necessary to recharge the bike battery is measured using an energy logger. This recharge energy is used as an indirect measure of the electricity consumption. A PV prototype system is installed on the bike. It is a simple PV stand alone system consisting of PV panel, charge controller with MPP tracker and a solar battery. This system has the task to generate as much electricity as possible. The produced PV current and voltage aremeasured and documented using a data logger. Afterwards the average PV power is calculated. To compare the produced electricity of the on-bike system to that of a stationary system, the irradiance on the latter is measured simultaneously. Due to partial shadings on the on-bike PV panel, which are caused by the driver and some other bike parts, the average power output during riding the bike is very low. It is too low to support the motor directly. In case of a similar installation as the PV prototype system and the intention always to park the bike on a sunny spot an on-bike system could generate electricity to at least partly recharge a bike battery during one day. The stationary PV system using the same PV panel could have produced between 1.25 and 8.1 times as much as the on-bike PV system. Even though the investigation is done for a very specific case it can be concluded that anon-bike PV system, using similar components as in the investigation, is not feasible to recharge the battery of a pedelec in an appropriate manner. The biggest barrier is that partial shadings on the PV panel, which can be hardly avoided during operation and parking, result in a significant reduction of generated electricity. Also the installation of the on-bike PV system would lead to increased weight of the whole bike and the need for space which is reducing the storage capacity. To use solar energy for recharging a bike battery an indirect way is giving better results. In this case a stationary PV stand alone system is used which is located in a sunny spot without shadings and adjusted to use the maximum available solar energy. The battery of the bike is charged using the corresponding charger and an inverter which provides AC power using the captured solar energy.
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Germania-Based Sol-Gel Organic-Inorganic Hybrid Coatings for Capillary MicroextractionFang, Li 01 April 2009 (has links)
For the first time, germania-based hybrid organic-inorganic sol-gel materials were developed for analytical sample preparation and chromatographic separation. Being an isostructural analog of silica (SiO2), germania (GeO2) is compatible with silica network. This structural similarity, which is reflected by the relative positions of germanium and silicon in the periodic table, stimulated our investigation on the development of germania-based sol-gel hybrid organic-inorganic coatings for analytical applications.
Sol-gel sorbents and stationary phases reported to date are predominantly silica-based. Poor pH stability of silica-based materials is a major drawback. In this work, this problem was addressed through development of germania-based organic-inorganic hybrid sol-gel materials. For this, tetramethoxygermane (TMOG) and tetraethyoxygermane (TEOG) were used as precursors to create a sol-gel network via hydrolytic polycondensation reactions to provide the inorganic component (germania) of the organic-inorganic hybrid coating. The growing sol-gel germania network was simultaneously reacted with an organic ligand that contained sol-gel-active sites in its chemical structure. Hydroxy-terminated polydimethylsiloxane (PDMS) and 3-cyanopropyltriethoxysilane (CPTES) served as sources of nonpolar and polar organic components, respectively. The sol-gel reactions were performed within fused silica capillaries. The prepared sol-gel germania coatings were found to provide excellent pH and thermal stability. Their extraction characteristics remained practically unchanged after continuous rinsing of the sol-gel germania-PDMS capillary for 24 hours with highly basic (pH=13) and/or acidic (pH = 1.3) solution. They were very efficient in extracting non-polar and moderately polar analytes such as polycyclic aromatic hydrocarbons, aldehydes, ketones. Possessing the polar cyanopropyl moiety, sol-gel germania cyanopropyl-PDMS capillaries were found to effectively extract polar analytes such as alcohols, fatty acids, and phenols. Besides, they also showed superior thermal stability compared with commercial cyano-PDMS coatings thanks to the covalent attachment of the coating to capillary surface achieved through sol-gel technology. Their extraction characteristics remained unchanged up to 330°C which is significantly higher than the maximum operation temperature ( < 280 ºC) for commercial cyano-PDMS coatings. Low ng/L detection limits were achieved for both non-polar and polar test solutes. Our preliminary results also indicated that sol-gel hybrid germania coatings have the potential to offer great analytical performance as GC stationary phases.
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Envelopes of broad band processesVan Dyke, Jozef Frans Maria January 1981 (has links)
Thesis (M.S.)--Massachusetts Institute of Technology, Dept. of Civil Engineering, 1981. / MICROFICHE COPY AVAILABLE IN ARCHIVES AND ENGINEERING. / Bibliography: leaf 93. / by Jozef Frans Maria Van Dyke. / M.S.
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Study on non-equilibrium quasi-stationary states for Hamiltonian systems with long-range interaction / 長距離相互作用を有するハミルトン系の非平衡準定常状態に関する研究Ogawa, Shun 24 September 2013 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(情報学) / 甲第17924号 / 情博第506号 / 新制||情||89(附属図書館) / 30744 / 京都大学大学院情報学研究科数理工学専攻 / (主査)教授 梅野 健, 教授 中村 佳正, 教授 船越 満明 / 学位規則第4条第1項該当 / Doctor of Informatics / Kyoto University / DFAM
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Optical True Time Delay Device for mm-Wave Antenna Array BeamformingAlmhmadi, Raed Ali M January 2019 (has links)
No description available.
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Adaptive Identification of Classification Decision Boundary of Turbine Blade Mode Shape under Geometric UncertaintyBoyd, Ian M. 30 August 2019 (has links)
No description available.
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Karlin Random Fields: Limit Theorems, Representations and SimulationsFu, Zuopeng January 2020 (has links)
No description available.
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Batteries and the Electrification of Heavy-Duty Transportation : Battery Development and its Impact on the Provision of Charging Infrastructure in Sweden / Batterier och elektrifieringen av tunga vägtransporter : Batteriutvecklingen och dess påverkan på tillhandahållandet av laddinfrastruktur i SverigeCameron, David January 2019 (has links)
Due to legislative pressure on a global, European and Swedish level the heavy-duty transportation sector needs to drastically reduce its emissions. One potential pathway forward for the heavy-duty transportation sector is that of electrification, which would require novel infrastructure to be established in the form of stationary charging or dynamic charging through what is often called electric road systems (ERS). The aim of this thesis has been to investigate how developments in battery technology impacts the potential electrification of heavy-duty transportation in Sweden. The starting point is from the perspective of battery technology and the resulting impact that battery technology has on the provision of charging infrastructure. In order to analyse the relation between these parameters the market developments of lithium-ion batteries were explored and an empirical study of the likely stakeholders of an electrified heavy-duty transportation system was conducted. The study finds that battery technology has a substantial momentum and several stakeholders view the electrification of heavy-duty transportation as the most cost-efficient solution in the long-term. There is however a consensus that battery development has not yet progressed to a stage where the electrification of heavy-duty transportation is financially or technically viable. Developments in battery technology affect the prospects for stationary charging provision and ERS (i.e. dynamic charging) differently, with stationary charging being more dependent on positive developments. The relation between developments in battery technology and ERS is more complex as its deployment is not only dependent on market developments but is also highly dependent on decisive actions by policy makers. Developments in battery technology could however affect both alternatives positively in the long-term, as a sustained positive battery development will make fully electric heavy-duty trucks an attractive option for the market to pursue. Once a common belief in the electrification of heavy-duty transportation has been established the main issue described by stakeholders, ensuring a long-term positive business case, could therefore be achieved by both alternatives. The study concludes that for an electrification of heavy-duty transportation to be financially sustainable in the long-term, continued positive battery developments are a prerequisite. / Till följd av lagstiftningskrav på en global, europeisk och svensk nivå så måste tunga vägtransporter drastiskt minska sina utsläpp. En möjlig utveckling för tunga vägtransporter kan vara elektrifiering vilket skulle kräva en etablering av ny infrastruktur, antingen i form av stationära laddstationer, eller i form av elvägar. Syftet med denna uppsats har varit att utreda hur batteriutvecklingen påverkar förutsättningarna för att tunga vägtransporter i Sverige skulle kunna elektrifieras. Utgångspunkten har varit utifrån perspektivet av batteriteknologi och den påverkan som batteriteknologin har på tillhandahållandet av laddinfrastruktur. För att analysera relationen mellan dessa parametrar så har marknadsutvecklingen för litium-jon batterier utretts och en empirisk studie med de aktörer som troligen skulle vara delaktiga i ett elektrifierat transportsystem har utförts. Studiens slutsatser är att batteriteknologin har ett betydande momentum och att flera aktörer på sikt ser elektrifieringen av tunga vägtransporter som den mest kostnadseffektiva lösningen. Det råder dock en konsensus om att batteriutvecklingen ännu inte har kommit långt nog för att elektrifieringen av tunga vägtransporter ska vara tekniskt eller ekonomiskt gångbar. Batteriutvecklingen påverkar utsikterna för tillhandahållandet av stationära laddstationer och elvägar på olika sätt, där stationära laddstationer är mer beroende av en positiv batteriutveckling. Relationen mellan batteriutvecklingen och elvägar är mer komplex då etableringen av elvägar inte bara är beroende av marknadsförhållanden utan även är avhängig på ett starkt politiskt stöd. Batteriutvecklingen kan dock ha en positiv påverkan på båda dessa alternativ på lång sikt, då en ihållande positiv batteriutveckling skulle göra helelektriska tunga lastbilar till ett attraktivt alternativ för marknaden att eftersträva. När en gemensam övertygelse om att elektrifieringen av tunga vägtransporter är den optimala vägen framåt har uppnåtts så kan det huvudsakliga problemet som aktörer beskriver, upprättandet av långsiktigt hållbara affärsmodeller, uppnås av båda alternativen. Studien drar slutsatsen att för att en elektrifiering av tunga vägtransporter ska vara ekonomiskt hållbar på sikt så är en fortsatt positiv batteriutveckling en förutsättning.
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