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Mist Characterization in Drilling 1018 SteelCole, Ian 08 1900 (has links)
Minimum quantity lubrication replaces the traditional method of flood cooling with small amounts of high-efficient lubrication. Limited studies have been performed to determine the characteristics of mist produced during MQL. This study investigated the mist concentration levels produced while drilling 1018 steel using a vegetable based lubricant. ANOVA was performed to determine whether speed and feed rates or their interactions have a significant effect on mist concentration levels and particle diameter. It was observed that the concentration levels obtained under all four speed and feed rate combinations studied exceeded the current OSHA and NIOSH standards.
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An Investigation of the Performance of Hot Mix Asphalt (HMA) Binder Course Materials with High Percentage of Reclaimed Asphalt Pavement (RAP) and RejuvenatorsVeeraragavan, Ram kumar 28 April 2016 (has links)
Use of high percentage of Reclaimed Asphalt Pavement (RAP) material in Hot Mix Asphalt is one of the several sustainable construction alternatives being considered by many Departments of Transportation (DOT). Use of RAP in HMA helps in reducing the consumption of virgin aggregates and binder and construction cost and conserving energy. Although most of the US state agencies allow the use of 30% or more RAP in the design of Hot Mix Asphalt (HMA), the current average RAP usage is only about 10 to 20%. This is because of the uncertainty about the performance of HMA mixes with a high RAP content. Several factors influence the performance of the HMA mixes with a high RAP content. Recent research has shown that the use of a high RAP content in HMA with rejuvenators is successful in reducing the stiffness of the RAP mixes, and thereby improving their performance. The present work is carried out to explore the feasibility of using a high RAP content of 50% in a binder layer HMA with the addition of rejuvenators. Ultrasonic Pulse Velocity (UPV) test was carried out to compare the stiffness of the RAP mixes with and without the addition of rejuvenators. Moisture Induced Stress Test (MIST) was conducted to study the effect of moisture damage on the HMA mixes with high RAP content. The Indirect Tensile Strength Test (ITS) was used to determine the strength of the HMA mixes with high RAP content. In addition, creep compliance and Semicircular Bend (SCB) tests were carried out to determine the cracking potential and fracture strength of the mixes respectively. The addition of rejuvenators was found to significantly reduce the stiffness of the mix with high RAP content. The predicted complex shear modulus (G*) obtained from the Hirsch model and performance grading tests on extracted binders confirmed the effectiveness of the addition of rejuvenators in reducing the stiffness of recycled asphalt binder in the recycled mixes.
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Air as a rooting medium : an experimental air-mist chamber system for rooting cuttings using Forsythia x intermediaDodd, Melvin Ennis January 2011 (has links)
Digitized by Kansas Correctional Industries
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Electro-optical properties of Sn doped In2O3 thin film derived from an ultrasonic atomization processHung, Chia-Chien 23 July 2002 (has links)
A thin film deposition system using ultrasonic atomization is designed and constructed. The coatings have been produced by pyrolysis using a solution of indium chloride in deionized water. Solution containing precursors is transported by carrying gas to the heated substrate where deposition is accomplished. In this study sample series obtained with of varying process parameters such as the flow rate of carrying gas, the tin concentration, and substrate temperature.
The electrical properties of indium oxide thin film was improved using SnCl4¡E5H2O as a dopant. The effects of doping in crystalline, surface morphology, optical transmittance and electrical conductivity of the deposition thin films were examined and the best optimal percentage of doping for the transmittance and electrical properties were found.
Weak diffraction peaks of crystalline indium oxide were observed in XRD pattern of the thin films deposition at 250¢J. The grains size of crystalline thin films grows with increasing substrate temperature. There is no change in XRD spectra between undoped and tin-doped indium oxide obtained with the same deposition temperature. The resistivity of thin films decreased greatly when dopant atom was added. The electrical resistivity of undoped indium oxide is ~10-2£[-cm, while that of ITO films reaches a minimum of 9.54¡Ñ10-4£[-cm when doping is in the range 2~ 6%.The UV-Visible spectra indicate that the optical transmittance of all films is between 75~88%. The transmittance was not strongly affected by doping concentration.
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Caractérisation stochastique des sprays ultrasoniques : le formalisme de l'entropie maximaleDobre, Miruna 09 May 2003 (has links)
Développer une méthode de caractérisation théorique complète d'un spray sur base de la connaissance du mécanisme de formation des gouttes et pouvant être appliquée de façon similaire quel que soit le type de spray, constitue l'axe central de la présente recherche. La difficulté principale étant la connaissance de la physique de rupture de la nappe liquide en gouttelettes, l'étude entreprise s'est attachée à la description du spray ultrasonique, qui a l'avantage d'impliquer un mécanisme de formation d'ondes de surface (ondes de Faraday) largement étudié. Les moyens mis en oeuvre pour trouver la loi de distribution théorique qui décrit au mieux la pulvérisation ultrasonique sont, d'un côté, l'analyse de l'instabilité des ondes de surface, qui permet de déterminer les caractéristiques moyennes du spray, et de l'autre, une méthode stochastique, le formalisme de l'entropie maximale, qui fournit la distribution la plus probable basée sur les caractéristiques moyennes et sur les lois de conservation élémentaires applicables à tout type de pulvérisation (conservation de la masse et de l'énergie). La validation expérimentale de cette nouvelle approche théorique a permis en outre de développer de nouveaux designs de pulvérisateurs performants.//
To develop a method of complete theoretical characterization of a spray based on the knowledge of the of droplet formation mechanism and being able to be applied in a similar way whatever the type of spray, constitute the central axis of this research. The main difficulty being the knowledge of the physics of liquid film break-up into droplets, the study undertaken was concerned with the description of the ultrasonic spray, which has the advantage of implying a mechanism of formation of surface waves (Faraday waves) largely studied. The means implemented to find the theoretical droplet size distribution which describes ultrasonic atomization as well as possible are, first, analysis of surface waves instability, which allows to determine the average characteristics of the spray, and then, a stochastic method, the maximum entropy formalism, which provides the most probable distribution based on the average characteristics and the elementary laws of conservation applicable to any type of atomization (mass and energy conservation). The experimental validation of this new theoretical approach made it possible moreover to develop new designs of powerful ultrasonic atomizers.
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Mist : - en hypnotiserande omvandling av en vardagsproduktBergfeldt, Sofia January 2018 (has links)
Mitt projekt handlar om att visa på ett alternativt sätt att tänka när vi designar elektronikprodukter. Det handlar om att designa för att hitta tid för vila och återhämtning. I en kultur som är besatt av effektivitet prioriteras ofta tiden för reflektion bort. Vi skapar ny teknik för att allt i samhället ska bli smidigare och gå snabbare. Jag har tittat närmare på elektronikprodukter vi har runt oss i vardagen, på deras estetik och användning. Jag har valt ut en produkt från den kategori; luftfuktaren. En produkt vars syfte är att portionera ut fukt till luften för att ge en bättre atmosfär. Jag kommer ge luftfuktaren nya värden utöver det rent praktiska den redan har idag. Hur skulle en luftfuktare se ut och användas ifall den inte bara skänker fysisk återhämtning utan även gav mental återhämtning? I projektet arbetar jag med luftfuktarens mist som material. Med dess estetiska kvalitéer och rörelse vill jag skapa en upplevelse som förhoppningsvis kan ge betraktaren en stund av vila.
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Potenciál uskupení MIST a jeho vliv na mezinárodní obchod / Potential of MIST and its influence on international tradeGecko, Alexandr January 2015 (has links)
The thesis deals with the analysis of MIST markets (Mexico, Indonesia, South Korea and Turkey) in comparison to BRIC countries. The aim of the thesis is to emphasise the attractiveness and potential of MIST economies for international business and investments relating to their growing competitiveness. The first chapter introduces world trends in international trade and it describes the origin as well as the development of the group. The carried-out macroeconomic and demographic analysis in the second chapter reveals strengths and weaknesses of the MIST. The third chapter describes trade activities of the MIST and its current position in international trade. The fourth chapter analyses the entrepreneurial and investment environment of the group as well as its level of competitiveness. The carried-out research in the thesis has shown that the MIST economies represent a perspective group of developing markets with potential for trade and investment activities.
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Ethanol Mist to Control Salmonella enterica serovar Newport on Fresh Tomato and Cantaloupe SurfacesWesolowski, Michael Christopher 28 June 2019 (has links)
Water used in fresh produce washing is a potential vehicle of foodborne pathogen contamination. This work focused on assessing the sanitizing efficacy of ethanol mist to reduce Salmonella populations on the surfaces of tomatoes and cantaloupes. Ethanol (70%) mist was applied to whole tomatoes and cantaloupe rind plugs using a Biomist sanitation system, which uses CO2 as a carrier gas to spray vapors through a fine droplet spray nozzle. Fresh red tomatoes (Solanum lycopersicum) and cantaloupe (Cucumis melo) plugs were inoculated with Salmonella enterica Newport to a concentration of log 7 CFU/tomato and log 7 CFU/cm2 respectively. Application time (5, 10, and 15 sec), dry vs. wet surface, and stem scar contamination were evaluated on tomatoes, while only application time was evaluated on cantaloupe. Application of ethanol mist for 10 seconds was the most effective treatment time, reducing Salmonella by 3.3 log CFU/tomato. Application of ethanol mist was more effective on dry opposed to wet tomato surfaces by approximately 0.7 log CFU/tomato. Ethanol mist application to inoculated tomato stem scars reduced Salmonella 1.2 log CFU/tomato. Additionally, Salmonella decreased by 1.3 log CFU/cm2 on cantaloupe rind plugs at 10 seconds, again the most effective treatment time. Ethanol mist resulted in sufficient reductions of Salmonella populations on dry tomato surfaces, but was limited in effectiveness if the surface was wet, or if Salmonella adhered to the stem scar. Furthermore, this technique was overall not an efficient method to sanitize cantaloupe surfaces. / Master of Science in Life Sciences / Water is often used in washing and moving fresh produce during harvesting. However, this water is often found to be a source of contamination that can cause the fruits or vegetables to become unsafe to eat. In order to resolve this problem, a mist-type sanitizing system is being explored to wash fresh produce in packinghouses. In this experiment, a mist of ethanol (70%) was applied to whole tomato and cantaloupe plugs using a Biomist sanitation system, which turns liquids into a mist. Whole fresh tomatoes and cantaloupe plugs were infected with Salmonella enterica bacteria. Tomatoes and cantaloupe plugs were treated with ethanol mist for various times of 5, 10, or 15 seconds. Additionally, tomatoes were treated with ethanol to compare a wet surfaced tomato, as well as the tomatoes stem scar (where the vine of the tomato is attached during growing). Ethanol mist application was most effective at 10 seconds, but there was very little difference in bacterial elimination when all the times were compared to the untreated tomatoes. In addition, the mists effectiveness decreased if the surface of the tomato was wet compared to dry, and was even less effective if the bacteria were located where the vine attaches. Also, the ethanol mist has very little effect if bacterial contamination is present on a cantaloupes surface. If a harvested tomato remains dry post harvest, ethanol mist may make for a good washing system. However, it is probably not the best for rough surfaced produce like cantaloupes.
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Effects of inoculum density, carbon concentration, and feeding scheme on the growth of transformed roots of Artemisia annua in a modified nutrient mist bioreactorTowler, Melissa J. 05 May 2005 (has links)
Previous work has shown that despite the lack of oxygen limitation, transformed roots of Artemisia annua had lower biomass productivity in a nutrient mist bioreactor than in a liquid-phase bubble column reactor where the roots demonstrated metabolic signs of oxygen stress. Mathematical modeling suggested that the roots were too sparsely packed to capture mist particles efficiently and to achieve high growth rates. In this study, higher packing fractions were tested, and the growth rate increased significantly. Similarly, higher sucrose concentrations increased the growth rate. Growth kinetics for 2, 4, and 6 days showed an unexpected decrease or stationary growth rate after only 4 days for both 3% and 5% sucrose feeds. Residual media analyses indicated that carbon was not exhausted, nor were other major nutrients including phosphate. Increasing the misting frequency such that the total amount of carbon delivered from a 3% sucrose feed was equivalent to that delivered in a 5% sucrose feed showed that growth was affected by the modified cycle. These studies showed that both the concentration of carbon source and alteration of misting frequency can significantly increase growth rates of hairy roots in mist reactors.
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Embedded programming and construction of the PCB SiC In Space ExperimentHatemipur, Hussein January 2018 (has links)
This thesis consists of the compilation of four previous bachelor theses as well as the continued work that has been carried out within the SiC in Space project, which is a part of the student satellite project MIST in KTH. SiC in Space is a project whose aim is to examine and verify the characteristics of the semiconductor Silicon Carbide, SiC, in harsh environments, in space specifically. In order to carry out the tests on SiC, a PCB was designed, where the BJT measurement circuits, voltage circuits, selection of MCU as well as software, assembling and testing of the final PCB, were divided in four parts, due to the size of the project. This work discusses testing, programming and verifying of the previous designed PCB:s as well as the design of a new PCB which includes new requirements and specifications from MIST. A test oriented approach of programming was made to verify that the circuits met the desired functions in order to put together a complete programme for automatic measuring and communication with the satellite. The errors that were discovered in carried out tests, were adjusted for the new PCB, making it in accordance with all the requirements set by the MIST- and SiC group. / Detta examensarbete bygger vidare på de fyra tidigare kandidatuppsatserna som har avhandlats samt det fortsatta arbetet inom SiC in Space projektet, vilket ingår i KTHs student satellit projekt MIST. SiC in space är ett projekt vars ändamål är att undersöka och verifiera halvledarmaterialet kiselkarbid, SiC, karakteristik i tuffa miljöer, specifikt i rymden för detta projekt. För att kunna göra tester på SiC designades ett kretskort, där experimentkretsarna, spänningskretsar, val av mikrokontroller samt mjukvara och montering och testning av det slutgiltiga kortet delades upp i fyra delar på grund av omfattningen av projektet. Detta arbete avhandlar i synnerhet testning, programmering samt verifiering av tidigare designade PCB tillika designen av ett nytt PCB inkluderande nya krav och specifikationer från MIST. En testorienterad programmeringsansats gjordes för att verifiera att kretsarna uppfyllde de önskade funktionerna för att sedan sammanställa ett fullständigt program för automatisk mätning och kommunikation med satelliten. De fel som upptäckts efter utförda tester har justerats för den nya PCBn, vilket i dagsläget uppfyller alla krav satta av både MIST och SiC gruppen.
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