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5012 Uppsatser om High-pressure - Sida 5 av 335
Enantioselektiv HPLC-analys med kirala stationärfaser bestående av makrocykliska glykopeptider och polysackarider
The purpose of this study was to evaluate enantioselective analytical methods by separation of the enantiomers of four drugs (citalopram, zopiclone, tramadol and methylphenidate) and their metabolites. The analyses were performed with HPLC-UV with columns whose stationary phases were based on macrocyclic glycopeptides (Chirobiotic V, V2 and T) and polysaccharides (Lux Cellulose-1, Cellulose-2 and Amylose-2).The Chirobiotic V column showed high selectivity for citalopram and its metabolites. High resolution was obtained using a mobile phase consisting of methanol, acetic acid and ammonia. High selectivity for the enantiomers of zopiclone and its metabolites were obtained on the Cellulose-2 column using a mobile phase consisting of acetonitrile and ammonium acetate buffer.The enantiomers of tramadol were separated with the Amylose-2 column. However, changes in the pressure arose, probably caused by the additive NH4HCO3.
Robothandel ? En rättvis arena? -En litteraturstudie om Robothandeln med aktier
The purpose of the thesis is to demonstrate how high frequency trading affects the stock market. The growing high frequency trading is affecting the game plan on the financial markets and concerns have grown about the high frequency users intentions with their business. It is difficult to receive an overall picture of the subject because the lack of previous research and even the research that exist do not show the entire picture. The thesis contributes to the research through a comprehensive picture of the present debate as well as the previous research through a literature study. Our results showed that high frequency trading provides liquidity to the market, there is a statistical connection between high frequency trading and volatility, no price manipulation is being used and there is a need for a supervision of the high frequency trading..
Processdatorsystem för tryckreglering
The task of this project was to build an computer processing system for pressureregulation, in which the pressure loss over the open hydrolicvalve should be kept as low as possible. By using an cross connected proportional directional valve the valve problem could be solved. The control- and regulationproblem for the pressureregulation system was solved by using the DAQ- card NI6035E from National Instruments and the computerprogram Automatic Pressure Control 1.0 which has been software developed and written in Visual Basic. The final result showed that correct processvarible was obtained in 0,5 seconds, when the setpoint was changed in the testarea 0 - 2,5 MPa..
Jämförelse av fyra rundbalspressars packningsförmåga som funktion av grödans torrsubstanshalt :
To succeed, and make money at your animal production you need to feed your animals with
high quality fodder. Other condition to succeed is that you keep your production costs at a minimum. To be able to produce baled silage at a low cost it?s very important that the bales have a high density. Density is measured in kg dry matter (DM) per cubic meter.
The purpose with this report was to learn more about making silage in round bales and to how much the bale density varies between different brands of round balers.
Modellering och simulering av det evaporativa bränslesystemet i en personbil
This thesis work has been performed at the department of diagnosis and dependability at Volvo Car Company, Torslanda. The background of this project is based on interest in ascertaining how different factors possibly can affect a diagnosis method, which has been developed to find leaks in the fuel tank and evaporation system. According to the OBD II requirements leaks with an orifice diameter larger or equal to 0,5 mm, must be detected. The idea of the diagnosis method is to create an over pressure in the system with an air-pump. The current through the pump is measured and correlates to the power consumed by the pump.
En statistisk undersökning av transkriptionsnoggrannheten i kodande DNA-sekvenser i E.coli-bakterien
Bacteria are exposed to evolutionary pressure to an extent unlike other organisms. This leads to a high degree of adaptation to its surrounding. This thesis investigates the degree of adaptation towards higher accuracy in the transcription of DNA to RNA in coding sequences in the DNA of the E. coli bacteria. Two coding sequences with different nucleotide contents were investigated.
Dynamic obstructions of the equine upper respiratory tract
Dysfunction of the upper respiratory tract is a common cause of impaired performance and intolerance to exercise in racehorses and include several upper airway obstructions. The ones termed dynamic obstructions are primarily seen during physical exertion and affected horses often appear to be normal during endoscope examination at rest. The correlation between diagnoses made at rest respectively exercise is low, suggesting that an examination at rest alone is likely to be insufficient.
The upper respiratory tract is exposed to great differences in pressure throughout the respiratory cycle; variations that are further altered during strenuous exercise and affect the rigidity of upper airway structures. In presence of great fluctuations in pressure, stability is achieved through coordinated and synchronous neuromuscular mechanisms. Due to nerve damage or anatomical abnormalities, these functions may be disrupted and further cause a dynamic collapse of the upper respiratory tract when pressure changes become too severe.
The etiology behind the neuromuscular dysfunction is not yet fully understood.
Högtrycket-Initierande undersökning av nytt limträmaterial
The present study examines a new production line of glue-laminated wood (glulam). The glulam is produced from non-planed boards of spruce, which also is convex, that is pressed together with high pressure during the gluing. According to a economic calculation, the material has a economical potential mainly on account of the absent planning. The study mainly found out that the shear strength of the material tolerated the demanded values in standard SS-EN 386, but the delaminating values did not. Since there are more areas to be studied around the material, the prospect to achieve the right delamination values is seen as positive..
V-modulen, en del av en hållbarhetsstrategi.
The state of our society is frequently changing. Due to various factors, the pressure of creating a changeable city is high and necessary to adequately supply the needs for its inhabitants. But making these changes and adapt to the fast shifting state of the city is not always physical possible. Young adults and students is a group that often seeks to move to intensely growing city regions. The reason for this is a more promising job market and more attractive educations, but coincidentally the shortage of housing is extremely high in these areas.
High Cereal Prices : An analysis of the causes behind the increase in the world market price of corn, rice and wheat.
The purpose of this study is to examine which factors played an important role in the food price crisis of 2007-2008. Theories used are Microeconomic theory, explaining changes in supply and demand, and Macroeconomic theory, explaining the impact of changes in exchange rate on prices. A theory regarding speculation is also used to explain the impact of speculative activities effects on price. The method used is multiple regression analysis in order to determine the effects which ethanol production, oil price and dollar exchange rate had on the surge in the price of corn, rice and wheat.The data used is in monthly observations during the period 2005-2008. However, other factors are taken into consideration during the study, such as production quantity, stock size, economic growth, speculative activity and population growth.
Mjölkraskvigors tillväxt på naturbete :
To turn the dairy heifers out on pasture is the most natural way for the cattle to get feed.
At the same time it is cheap and if it is right treated a feed of high nutritive value. The
problem today is to get dairy heifers to grow enough when they are grazing at natural
pasture for the entire summer. Therefore, the opinions differ whether pasture is a
resource or a problem.
The increasing interest of pasture production is due to the fact that you can receive
grants for preserving valuable natural assets and cultural landscape elements in the
pasture land.
A high grazing pressure is necessary to preserve an open landscape and a great variety
of species. In the same time the heifers have to supply their nutritive needs in order to
grow and be large enough to show heat and be pregnant in right time to calve with a
sufficient body size and at an economically right age.
This paper includes a literature review on natural pasture, pasture production, and
growth of dairy heifers together with own interviews with dairy farmers about their
point of view to the pasture husbandry on the farms, how they plan for pasture, look
after natural pasture, treatment areas and take care of the calves and heifers. The results
indicate that the time it takes and the demanded work are the biggest factors to how and
why the farmers do as they do..
Ett mät- och reglersystem för temperaturkompensering
An automatic control system for calibration of pressure indicators has been constructed. This control system can be used as a complement to the calibration system located at AerotechTelub, division MainPartner, in Linköping. The calibration system used today contains some not wanted pressure changes, which is compensated by hand today. The new system presented in this report automates the calibrating process and simplifies the calibration. Suitable hardware as motor, controls card and so on have been found and software in the form of Visual Basic program has been developed.
Expansionsmaskiner istället för strypventiler - en effektivisering
In Uppsala CHP Plant, there are six pressure reducing valves to reduce the pressure from 15 to 3 bars, before six absorption heat pumps. During the process the energy is conserved but losses occur in form of exergy. The aim of this thesis is to reduce the losses of exergy. This can be done by letting turbines replace the pressure reducing valves.In this thesis an investigation has been done of the conditions today, the conditions after the change from pressure reducing valves to turbines and a comparison of three different types of turbine solutions. The three examined solutions are one turbine, several helical screw expanders and several small turbines in parallel with asynchronous generators.The six absorption heat pumps have been divided into two groups; one group of four and one group of two absorption heat pumps.
Evaluation of indirect blood pressure measurement, plasma endothelin-1 and serum cortisol in clinically healthy horses
Equine metabolic syndrome (EMS) it?s a clinical condition that includes obesity, regional adiposity, insulin resistance (IR) and laminitis. A similar syndrome exists in human medi-cine, the metabolic syndrome (MS), were systemic hypertension also is a prominent fea-ture. The systemic hypertension seen in humans with MS is partly due to a vascular endo-thelial dysfunction with an enhanced endothelin-1 (ET-1) mediated vasoconstriction. There are indications that systemic hypertension might be a feature in EMS as well but if ET-1 is involved in the development of the systemic hypertension in horses is not known.
Äh! Vadå nervös? Kör nu bara! : En studie om hur lärare och elever kan arbeta i gymnasieskolan för att lära sig hantera rampfeber
The purpose of our study is to find out how teachers can help their students to learn how to managestage fright. By interviewing high school teachers and high school students and also observe one oftheir classes, we wanted to find out how they think about the causes of stage fright and what youcan do to relieve it. We also wanted to find out how teachers are working to teach students how todeal with stage fright, and how they think that you also could work. As a teacher of music, among other things, the task is to assess and rate the students performancesin music. Several components are based on the students' courage to play on his or her instrument infront of other people.