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Estudo da influência de aditivos naturais nos pontos de entupimento a frio, de turbidez e de fulgor de biodiesel e de misturas diesel-biodiesel / Study of natural additive influence in cold filter plugging point, turbidity and flash point in biodiesel and diesel-biodiesel blendsMattos, Rodrigo Alves de, 1979- 21 August 2018 (has links)
Orientador: Matthieu Tubino / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Química / Made available in DSpace on 2018-08-21T17:49:21Z (GMT). No. of bitstreams: 1
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Previous issue date: 2012 / Resumo: O presente trabalho foi realizado usando biodieseis preparados a partir de óleos de soja, canola, milho, girassol e, também, de gordura suína, através de reações transesterificação. Para todos esses biodieseis foram determinados o ponto de entupimento a frio, o ponto de fulgor e o perfil cromatográfico. Estes biodieseis foram misturados com diesel de petróleo para se produzir misturas contendo 5% do biocombustível (B5), 10% (B10) e 20% (B20), e os ensaios citados foram realizados nestas amostras. Visando a diminuição do ponto de entupimento a frio, alguns aditivos naturais foram testados e se mostraram eficientes. Por exemplo, o limoneno reduziu o ponto de entupimento do biodiesel de óleo soja em mais de 7°C. No biodiesel de gordura suína a redução foi de 10°C, o que significa o ponto de entupimento a frio em temperatura inferior a 13°C. Os aditivos utilizados são solúveis nos biodieseis estudados e, também, nas misturas diesel-biodiesel, pelo menos nas concentrações testadas. Como importante exemplo de abaixamento do ponto de entupimento a frio das misturas diesel-biodiesel de gordura suína com 10% de biodiesel (B10), podese citar o caso da terebentina que provocou uma redução de aproximadamente 8°C (de 12,7ºC para 5,0°C). Este mesmo aditivo caus ou uma redução de 13,6 ºC (de 20,3ºC para 6,7ºC), na mistura diesel-biodiesel de gordura suína com 20% de biodiesel (B20). Este resultado é muito significativo por implicar na possibilidade de usar este tipo de combustível mesmo em regiões mais ao sul do país durante o inverno / Abstract: The present studies were performed preparing biodiesel from soya, canola, corn, sunflower oils and the fat swine, through transesterification reaction. The biodiesel produced from these oils were studied for: cold filter plugging point, flash point and for chromatographic analysis. The biodiesels were mixed with diesel to produce blends containing 5% of the biofuel (B5), 10% (B10) and 20% (B20), and these samples were also analyzed by the same techniques as discussed earlier. In order to decrease the cold filter plugging point, some natural additives have been tested and were proved effectively. For example, limonene caused more than 7°C reduction in the cold filter plugging point of soybean biodiesel. In the biodiesel obtained from the swine fats, the reduction was found around 10°C and less than 13°C for the cold filter plugging point. The additives are soluble in studied biodiesels and also in the dieselbiodiesel blends, at least, in the concentrations tested. One of the important example of the reduction in the cold filter plugging point of diesel-biodiesel blends of swine fats with 10% biodiesel (B10), using turpentine as additive which caused reduction of approximately 8°C (from 12,7ºC up to 5,0°C). The same additive caused a reduction of 13,6 ºC (from 20.3 ºC up to 6.7 °C) in the cold filter plugging point of diesel -biodiesel blends of swine fats with 20% biodiesel (B20). This result is very significant because it is possible to use this type of fuel in south regions of the country during the winter / Doutorado / Quimica Analitica / Doutor em Ciências
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Trihalomethane compounds in the drinking water of Kuwait : a survey from source to consumerLatif, Nidhal Abbas Abdul January 1991 (has links)
A comprehensive survey of the presence of trihalomethane (THM) compounds, as chlorination by-products, in drinking water in Kuwait have been performed. The survey covers the whole drinking water treatment cycle, starting with sea water and ending with the consumer tap. The data generated by the survey was all derived from actual water treatment plants, operating under normal conditions. All four trihalomethane compounds, namely; chloroform (CHCI3), bromodichloromethane (CHBrCI2), dibromochloromethane (CHBr2CI) and bromoform (CHBr3) were covered. The study clearly showed that, although considerable amounts of THM compounds did form as a result of chlorination of sea water entering the multi-stage flash (MSF) distillation plants, these plants were highly efficient in removing these compounds. The average removal efficiency, based on THM compounds mass load in the sea water feed, was around 95%. Factors which were found to have an influence on the degree of formation of these compounds, include, chlorination practice (continuous vs. shock), sea water temperature, level of organic precursors and contact time. Of much more important consequence, as far as the presence of these compounds in drinking water is concerned, was the degree of THM compounds formation as a result of the chlorination of drinking water before it is pumped to the consumer. Here, not only all the compounds formed remain in the water but there is a definite tendency for continuous formation well after the actual chlorination process has taken place. Factors which were found affecting this formation include water temperature, contact time and chlorination dosage. Although, all samples collected showed that the presence of THM compounds was always below the United States Environmental Protection Agency maximum contaminant level of 100 ~g/L, a need exists for the optimization of all chlorination processes with particular emphasis on the chlorination of drinking water. In almost all kinds of water encountered in this study, bromoform was found to be by far the most dominant compound.
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Trace element contaminants in the Kuwait water production systemAl Anqah, Laila January 1996 (has links)
Fresh water in Kuwait is produced by non- conventional methods. About 95% of this water comes from desalinated seawater using multi-stage flash distillation technique and the remainder comes from underground brackish water. The blended water containes organic, inorganic and trace metal impurities within the recommended international standard limits. The purpose of this work is to identify the source of selected trace metals present in the drinking water in Kuwait. Chromium, copper, iron, lead, manganese, nickel, vanadium and zinc have been analysed using atomic absorption spectroscopy (AAS) and inductively coupled plasma mass spectroscopy (ICPMS). Efforts were made to improve the preconcentration of the selected metals and their separation from the high concentration of salts in seawater which affect the accuracy and cause major interference in the analysis. Solid-liquid extraction (chelex-100 resin) and liquid-liquid extraction (methyl iso-butyl ketone and freon) with and without back-extraction into nitric acid were investigated. Liquid-liquid extraction without back-extraction proved to give optimum recovery of the selected metals. Results confirmed that both AAS and ICP-MS are suitable for the analysis of trace metals in Kuwait's waters. Although AAS technique proved to be more accurate in analysing the selected metals than ICP-MS, the latter was adopted since its accuracy is acceptable (1.1-4.4%) and it is easier and faster than the former technique. The study revealed that the source of copper, iron, nickel and zinc is the construction materials of the distillation plants, while the source of lead and vanadium is the brackish water. Manganese and chromium concentrations are very low in all sources. No direct relationship between the metal concentration in the seawater and the distillate could be deduced.
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Elgitarrskolan : En webbsida med inslag av interaktivitet / Guitarschool : A website with elements of interactivityHannila, Ari January 2005 (has links)
Elgitarrskolan är ett försök att skapa en webbsida med inslag av interaktivitet. Sidan är tänkt att fungera som en lärande miljö där besökaren ska lära sig att spela elgitarr, eller att vidareutveckla ditt spelande. Förutom själva spelandet ska sidan också ge gästen information om elgitarren och kringutrustning, med en del tekniska specifikationer, historik m.m. Elgitarrskolan är ett försök att sprida specifik kunskap genom att integrera flera olika medier till en fungerande enhet. Med hjälp av text, grafik, animationer, ljud, video och interaktiva element har jag försökt att göra informationen så lättillgänglig som möjligt och samtidigt intressant. Det huvudsakliga arbetet har varit att tillverka webbsidan och därför bör denna text endast ses som ett komplement. / Detta är en reflektionsdel till en digital medieproduktion. www.soundport.se
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Data Remanence : Secure Deletion of Data in SSDsHomaidi, Omar Al January 2009 (has links)
The ongoing fast pace research in hardware and software technology has resulted in memory devices efficient and faster than ever before. However, the issue of security of the contained data is rarely discussed. There is an evident capability of these devices to retain data even when it is erased. In this thesis, a study is conducted to qualitatively analyze the extent to which data deletion is important and why secure deletion should be applied. Afterwards, following the sequential exploratory procedure, this paper presents an analysis of methods used to recover the data after being deleted in addition to the techniques used to securely delete this data. Based on this study, some recommendations are made to ensure the safety of data.
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Hearty HorrorSvensson, Peter January 2009 (has links)
I denna text diskuterar jag produktionen av Hearty Horrors, ett spel programmerat och designat helt i flash. Jag diskuterar svårigheterna för de olika delarna i att skapa ett spel. Tankar och jämförelser mellan onda och goda karaktärer och vad man, som speldesigner, bör och inte bör göra för att få spelare att känna sig manade att spela vidare. In this text I discuss the production of Hearty Horrors, a game programmed and designed completly in flash. I discuss the difficulties of diffrent parts in the making of a game. Thoughts and comparances are made between evil and good characters and what you, as a gamedesigner, should and should not do to make the player want to continue playing. / Detta är en reflektionsdel till en digital medieproduktion.
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Projektdatabas mmErkstam, David January 2010 (has links)
Den här rapporten behandlar ett examensarbete där målet var att programmera en projektdatabas och projektöversikt åt Milton Medicinteknik KB. Syftet var att dess projektgrupper ska kunna komma åt att granska sina filer samt se filernas relationer med varandra, genom inloggning på en hemsida. Språken som användes var MySQL för att hantera databasen, PHP för att kommunicera mellan hemsidan och webbservern, HTML för att formatera webbsidorna och ActionScript 3 som är Flash programmeringsspråk för att programmera projektöversikten. I huvuddelen av rapporten är det beskrivet hur projektöversikten och projektdatabasen fungerar. Från hemsidan kan man ladda upp filer som hanteras av projektgrupper och användare med rätt rättigheter. Det finns tre typer av behörighet som användarna kan ha: Administratör som kan skapa användare och projektgrupper, projektledare som ansvarar för sin egen projektgrupp samt vanliga användare som endast kan ladda upp och länka filer i sin egen projektgrupp. Projektöversikten tillåter att användarna på ett överskådligt sätt kan se hur filerna som de har rättighet att se är länkade med varandra, lägga till och ta bort egna filer samt se deras innehåll.
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¿Lista de palabras o imágenes? : Un estudio comparativo entre dos métodos de aprendizaje de palabras en la clase escolar sueca. / ¿glossing or images?Restrepo Pulido, Mateo January 2014 (has links)
El propósito de nuestra investigación es analizar y comparar la efectividad de dos métodos de aprendizaje de palabras (el método del glosario y el método de aprendizaje por medio de las flash-cards) en una clase de grado séptimo en una ciudad de Suecia. La prueba realizada tiene un total de 32 palabras, divididas en dos grupos temáticos de 16 palabras cada uno, el primer grupo contiene palabras acerca de las partes del cuerpo y el segundo de la ropa. Nuestra investigación consta de tres pruebas, dos de ellas fueron respondidas por los estudiantes en el primer encuentro que tuvimos en el salón de clase y la prueba final se realizó una semana más tarde, después de utilizar los métodos de aprendizaje anteriormente mencionados. El resultado de este estudio muestra que la eficacia del método de aprendizaje de palabras con flash-cards es mayor y que los estudiantes muestran mayor motivación al momento de trabajar con imágenes que cuando trabajan con el método del glosario, el cual es el más usado en las aulas de clase de español de las escuelas suecas.
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Link Extraction for Crawling Flash on the WebAntelius, Daniel January 2015 (has links)
The set of web pages not reachable using conventional web search engines is usually called the hidden or deep web. One client-side hurdle for crawling the hidden web is Flash files. This thesis presents a tool for extracting links from Flash files up to version 8 to enable web crawling. The files are both parsed and selectively interpreted to extract links. The purpose of the interpretation is to simulate the normal execution of Flash in the Flash runtime of a web browser. The interpretation is a low level approach that allows the extraction to occur offline and without involving automation of web browsers. A virtual machine is implemented and a set of limitations is chosen to reduce development time and maximize the coverage of interpreted byte code. Out of a test set of about 3500 randomly sampled Flash files the link extractor found links in 34% of the files. The resulting estimated web search engine coverage improvement is almost 10%.
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Kök.Ett i ettor och nollor / Kök.Ett in ones and zerosOlsson, Oscar January 2004 (has links)
Jag har gjort en webbsajt åt företaget Kök.Ett i Älmhult. Kök.Ett är en köksbutik som bland annat ritar och säljer kök. Jag har byggt upp den allra största delen av hemsidan i Flash, och kompletterat med PHP och kopplat till en databas (MySQL). Sidan är komplett med ett eget administrationssystem. Sidan har en dynamisk känsla som inriktar sig på att inspirera besökaren, och föra besökaren/kunden ett steg närmare Kök.Ett och dess anställda. I’ve built a website for the company Kök.Ett in Älmhult, Sweden. Kök.Ett creates drawings and sells kitchens. I’ve built the site mostly in Flash, and used PHP where needed. MySQL is also used (database). The site is complete with its own administration system. / My cellphonenumber +46 (0)70 350 67 01
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