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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Estudio experimental del equilibrio líquido - vapor de una mezcla de Propan - 2 - OL y Tolueno a 101.32 kPa.

Aldana Rivera, Jesús Jhon January 2015 (has links)
Se ha realizado el estudio del equilibrio líquido vapor de la mezcla binaria de propan-2-ol y tolueno a una presión de 101.325 kPa. En este trabajo se han obtenido 12 puntos experimentales termodinámicamente consistentes según las pruebas de consistencia termodinámica de Redlich-Kister, Herington y Wisniak. La fase vapor se modela con tres ecuaciones cúbicas de estado: Peng Robingson, Soave Redlich Kwong y Virial generalizado, mientras que la fase líquida ha sido modelada por las ecuaciones de Margules, Van Laar, Wilson, NRTL y UNIQUAC. Con respecto a la reducción de datos, se ha desarrollado una aplicación en MATLAB R2012a para obtener los parámetros de interacción binaria de cada modelo propuesto para la fase líquida mediante la evaluación de un factor de optimización mínimo basado en la sumatoria de las diferencias de los coeficientes de actividad calculados y experimentales. De acuerdo a los resultados obtenidos el modelo de Wilson de dos parámetros asociado al modelo del Virial en la fase vapor en equilibrio, ajustan mejor el sistema propan-2-ol y tolueno. El punto azeotrópico experimental fue estimado a 354.4 K y 0.8361 de composición de propan-2-ol. La metodología desarrollada en el presente trabajo permite mejorar la precisión de la medición de propiedades de estado como la presión, temperatura y composición respecto de la data publicada sobre el mismo sistema a condiciones isobáricas. Palabras Claves: Equilibrio Líquido Vapor, propan-2-ol, tolueno.
2

The application of administrative theories to the Petroleum Authority of Thailand (PTT), should the Thai government give up control?

Akaramingmongkol, Wanchoke 03 June 2011 (has links)
This thesis explores the dynamics of public administration for the Petroleum Authority of Thailand (PTT), the state-owned oil enterprise under the jurisdiction of the Ministry of Thailand. The study shows how PTT adapts bureaucratic systems to organization theories.The thesis focuses on six segments in PTT: (1) Culture -- including bureaucratic political system, equality and efficiency, and the adaptiveness of the Thai culture; (2) Organization Theory and Structure -- including varieties of organization theory and traditional structure principles; (3) Personnel - including people, labor relations, leadership, and communication; (4) Budgets -- including privatization, productivity, efficiency and effectiveness, and program evaluation; (5) Regulations -- including administrative controls and administrative accountability; and (6) Organization Change -- including process of change in the public sector and reengineering in the public sector.The central problem is that the Thai government has no intention for giving up the control of PTT. The reason is because the PTT has made many gains in the oil, natural gas, and petrochemical businesses in Thailand. The Industry Minister, who is directly control the PTT, can recieve some gain from the PTT projects through the commission of each construction project and highest share from each subsidiary that wants to enter in the Stock Market of Thailand.However, because of the increasing and expanding of world oil market, PTT needs more flexibility and less control from the Thai government to compete with other nations. The study also shows that how PTT creates structure that moves with change, that is flexible and adaptive, and that enables rather than constrains while PTT is controlled by the Thai government. It also shows how PTT will solve this problem if the government is not ready to give up control.The methods used in this study are a review of relevant literature and government documents, news document, and interviews with top managers at PTT. The results of this study shows that it is time for the Thai government to give up control of PTT. The Industry Minister is unlikely to take drastic action in the first stage because it might negatively affect the PTT's business. To date, the energy situation has changed toward market-oriented operations. Therefore, the PTT needs more flexibility to compete with another companies both inside and outside the country.Ball State UniversityMuncie, IN 47306
3

Cultural Factors: Entrepreneurial Orientation or Not-Here Comes Innovation in Small to Medium Sized Enterprises

Chambers, Donald G. January 2016 (has links)
No description available.
4

Un estudio del uso de literatura en las clases de espanol como lengua extranjera en la educacion secundaria

Dearworth, Emily 18 September 2012 (has links)
No description available.
5

Aanvändning av lantmäteriets nya nationella höjdmodell (laserdata) i skogsmark / Application of land survey new national elevation model (Laserdata) in the forest land

Walid Hanna, Motaz January 2016 (has links)
Detta arbete redogör för hur användning av den nya nationella höjdmodellen (NNH) ur/i Lantmäteriet databas kan användas i olika terräng och vilka förutsättningar det finns för identifiering av specifika landskapselement i denna, manuellt och visuellt. Sedan 2009 har Lantmäteriet laserskannat hela landet, både på land och över vatten. Uppdraget är slutfört 2015. Målet med laserskanning är att framställa en rikstäckande höjdmodell med ett medelfel som är bättre än 0.5 m. Idag är all NNH-data tillgänglig som LAS-filer på Lantmäteriets databas. För att kunna utföra ett utvärderingsexperiment valdes ett geografiskt begränsat område: I Skepplanda, Ale kommun i Västra Götalands län. De hjälpmedel som användes var GPS-mottagare, LAS-filer, Ortofoto och applikationsprogram såsom OL-laser och ArcGis. Det främsta syftet med studien var att undersöka hur bearbetning och utvärdering av olika kartmaterial kan utföras, för att sedan kunna bedöma i vilken mån användning av Lantmäteriets NNH-data, i olika typer av terräng, kan vara möjlig t.ex. hur små detaljer kan urskiljas i det. För undersökningen valdes specifika objekt, såsom stenmurar och ett dike. Tre olika kartunderlag framtogs av OL-laserprogrammet: lutningsbilder, intensitetsbilder och terrängskuggningsbilder. Utifrån insamling av inmätta punkter och med hjälp av vektordata kunde materialet utvärderas visuellt. Två kartor valdes, vilka uppfyllde kriterierna för att kunna uppnå studiens syfte. Eftersom kartan med terrängskuggning och lutningsbild ger en tydligare profil av områdets karaktäristiska drag på marknivå, är det möjligt att identifiera små markdetaljer såsom stenmurar och diken. Resultatet varierade från fall till fall, beroende på kartunderlaget. En mur på den ena platsen i en bild kunde t.ex. detekteras, men inte i en annan bild, trots att det finns en mur där. Studien visade att laserpulserna har svårt att tränga igenom tät vegetation, dock kan olika solvinklar och belysningsriktningar ändå framhäva vissa små markdetaljer under en tätskog. Andra faktorer som kan ha påverkat kvalitén på lasermaterialet är flyghöjden, laserskannerns vinkel och under vilken period under året skanningen genomfördes. Ett antagande gjordes, att laserskanning från lägre flyghöjd och mindre öppningsvinkel kan höja kvalitén på laserdata. Med dessa två faktorer kan högre upplösning per kvadratmeter yta uppnås. Ett annat sätt som kan vara aktuellt i en undersökning är att använda OL-laser verktygslåda och tillämpa andra inställningar genom att skapa objekthöjdbilder där höjd färgläggs med olika ekvidansnivå. Genom att prova fram olika inställningar i programmet, där olika lutningshöjd och solvinklar tillämpas kan läsbarheten på kartunderlaget förbättras. / This work describes how the use of the new national elevation model (NNH) from the National Land Survey database may be used in a variety of terrain and the conditions they are identification of specific landscape elements, manually and visually. From the start of 2009, the national land Survey laserscannat whole country, both on land and over water. The mission will be completed in 2015. The goal of laser scanning is to produce a nationwide elevation model with a standard error of better than 0.5 m for a 2 m GRID. Today, all NNH data available as LAS files on Lantmäteriet's database. To perform an evaluation experiment was elected a geographically limited area: Skepplanda, Ale Municipality in Västra Götaland. The devices used were GPS receiver, LAS files, Orth imagery and application programs such as OL laser and ArcGIS. The main aim of the study was to investigate the processing and evaluation of different map material can be performed, and then to assess to what extent the use of Lantmäteriets NNH- data in different types of terrain may be possible. For the investigation, the specific items, such as stone walls and a ditch. Three different maps material was developed by the OL laser program: slope images, intensity images and terrain shading images. Based on the collection of measured points and using vector data could material evaluated visually. Two maps were chosen, which met the criteria for being able to achieve the objectives of the study. Since the map with terrain shading and gradient image provides a clearer profile of the area's characteristic features at ground level, it is possible to identify small land features such as stone walls and ditches. Results will vary from case to case, depending on the substrate maps. A wall at one location in an image could e.g. detect, but not in another image, even though it's a wall there. That’s why definitive conclusions could be not established. The study showed that the laser pulses are difficult to penetrate dense vegetation; however different solar angles and lighting directions nonetheless highlight some small land details during a dense forest. Other factor that may have affected the quality of the laser material is the altitude, laser scans angle and during which period of the year the scan was performed. An assumption was made that the laser scans from lower altitude and smaller opening angle can add value to laser data. With these two factors, higher resolution per square meter of surface is achieved. Another way that can be relevant in an investigation is to use the OL laser toolbox and apply different settings to create objects height pictures where height is colored with different evidence level. By trying out different settings in the program, where different slope height and solar angles applied to the readability of the chart surface is improved.
6

Study Of Sorption Of Alcohols On High Silica Zsm-35

Babuccuoglu, Yurdaer 01 January 2007 (has links) (PDF)
This study investigated the equilibrium sorption capacities and rates of sorption of some alcohols on Na- and/or H- form of ZSM-35 at different temperatures by gravimetric method using an electrobalance. The alcohols studied were methanol, ethanol, propan-1-ol, propan-2-ol, n-butanol. The ZSM-35 sample used in sorption experiments resulted from a study for synthesis of high silica ZSM-35 zeolite. This ZSM-35 sample was called as NaZSM-35. The influence of ion-exchange on the sorption capacity and kinetics was investigated by converting NaZSM-35 into H-form by the ion exchange method. In this method, a sufficient amount of ZSM-35 sample (200-250 mg) was mixed with 25 ml of 1 N NH4Cl solution for 24 hours at room temperature. This procedure was repeated until no Na+ was detected by a Flame Photometer. After the ion exchange was completed , the sample was washed with deionized water, filtered, dried and recalcined for the removal of the ammonia and this sample was denoted as HZSM-35. The highest sorption capacity (cm3/g) was observed for methanol on HZSM-35 / 0.1656 cm3/g and the lowest sorption capacity was observed for propan-2-ol at NaZSM-35 / 0.003 cm3/g. Sorption of methanol and ethanol were very rapid. The sorption capacities of other three alcohols / propan-1-ol, propan-2-ol and n-butanol, were lower and they had slower rates of sorption. HZSM-35 had greater limiting sorption capacity than NaZSM-35 for propan-1-ol, propan-2-ol and n-butanol at all temperatures.
7

Desenvolvimento e avaliação antimicrobiana “in vitro” de nanofibras de PLA/PEG com Terpinen-4-OL e clorexidina contra aggregatibacter actinomycetemcomitans

Barbosa, Mariangela de Araujo 28 January 2016 (has links)
Submitted by Viviane Lima da Cunha (viviane@biblioteca.ufpb.br) on 2017-07-17T13:50:01Z No. of bitstreams: 1 arquivototal.pdf: 995552 bytes, checksum: 2e508d438daa1802facd83d5885a5854 (MD5) / Made available in DSpace on 2017-07-17T13:50:01Z (GMT). No. of bitstreams: 1 arquivototal.pdf: 995552 bytes, checksum: 2e508d438daa1802facd83d5885a5854 (MD5) Previous issue date: 2016-01-28 / To determine the minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC) of terpinen-4-ol and chlorhexidine produce and characterize nanofibers PLA / PEG incorporated with terpinen-4-ol and chlorhexidine as well as quantifying the viability biofilm mobile Aggregatibacter actinomycetemcomitans (Aa) (ATCC 00078) grown on the surface of this inhibitory fiber. Methodology: The determination of MIC and MBC was performed by broth microdilution; the nanofiber terpinen-4-ol (40%) and chlorhexidine (0.12%) were produced by spinning blow solution (SBS) and characterized by scanning electron microscopy (SEM), thermal gravimetric analysis (TGA), calorimetry differential scanning (DSC) and infrared spectroscopy by Fourier transform (FTIR). The cell was observed by fluorescence quantification and nanofibers incorporated with chlorhexidine served as positive control for this assay. Results: There was an effective antimicrobial activity terpinen-4-ol (MIC and MBC = 25 mg / mL) and chlorhexidine (MIC and MBC <15 mg / mL) on planktonic cells pa PEG acted as a plasticizer resulting in a reduction in the crystallinity of the PLA, increased fiber diameter and lightweight thermal destabilization of the material. The increase in PEG concentration was not decisive for increasing the antimicrobial activity of the fibers but has contributed to formation of a more amorphous material. The terpinen-4-ol fibers showed similar antimicrobial activity to chlorhexidine fibers (p <0.05), and the Terpinen-4-ol fiber with 20% PEG had best performance among your group. Conclusion: The terpinen-4-ol and chlorhexidine had effective antimicrobial activity against A.A and SBS technique was effective in the production of PLA nanofibers / PEG antimicrobial action against A.A having the potential to drive future applications to combat periodontal disease. / Objetivo: Determinar a concentração inibitória mínima (CIM) e concentração bactericida mínima (CBM) do terpinen-4-ol e clorexidina, produzir e caracterizar nanofibras de PLA/PEG incorporadas com terpinen-4-ol e clorexidina, bem como e quantificar a viabilidade celular de biofilme de Aggregatibacter actinomycetemcomitans (A.a.) (ATCC 00078) crescido sobre a superfície inibitória desta fibra. Metodologia: A determinação de CIM e CBM foi realizada por microdiluição em caldo; as nanofibras de terpinen-4-ol (40%) e clorexidina (0,12%) foram produzidas através da fiação por sopro em solução (SBS) e caracterizadas por microscopia eletrônica de varredura (MEV), análise termogravimétrica (TGA), calorimetria exploratória diferencial (DSC) e espectrometria no infravermelho por transformada de Fourrier (FTIR). A quantificação celular foi verificada por fluorescência e as nanofibras incorporadas com a clorexidina serviam de controle positivo para este teste. Resultados: Observou-se uma efetiva atividade antimicrobiana do terpinen-4-ol (CIM e CBM = 25 μg/mL) e da clorexidina (CIM e CBM < 15 μg/mL) sobre células planctônicas de A.a. O PEG agiu como agente plastificante proporcionando redução na cristalinidade do PLA, aumento do diâmetro das fibras e leve desestabilização térmica do material. O aumento da concentração do PEG não foi determinante para o aumento da atividade antimicrobiana das fibras, embora tenha contribuído para formação de um material mais amorfo. As fibras de terpinen-4-ol apresentaram atividade antimicrobiana semelhante às fibras de clorexidina (p<0,05), sendo a fibra Terpinen-4-ol com 20% de PEG a que teve melhor desempenho dentre o seu grupo. Conclusão: O terpinen-4-ol e a clorexidina apresentaram efetiva atividade antimicrobiana sobre A.a e a técnica de SBS foi eficiente na produção de nanofibras de PLA/PEG com ação antimicrobiana frente a A.a tendo potencial para conduzir futuras aplicações no combate às doenças periodontais.
8

Edici?n ling??stica de la Cr?nica de Vivar: el tr?nsito de Burgos a Chile

Contreras Dur?n, Margarita January 2010 (has links)
Tesis para optar al grado de Mag?ster en Ling??stica menci?n Lengua Espa?ola / La tesis que a continuaci?n expongo ofrece un establecimiento cr?tico de la lectura de la Cr?nica de Jer?nimo de Vivar, ling??sticamente anotada y prologada. En ella doy cuenta de una visi?n descriptiva y anal?tica, no exhaustiva, de sus principales rasgos fon?ticos, morfol?gicos y sint?cticos. El estudio filol?gico-ling??stico se realiza sobre la base de una completa transcripci?n paleogr?fica de la obra, con el prop?sito de obtener un documento lo m?s fiel al original. Para ello, se contrastaron dos transcripciones de la misma: una de Leopoldo S?ez-Godoy (Coloquium Verlag, Berl?n, 1979) y otra realizada por el profesor Manuel Contreras Seitz. El estudio filol?gico, que se efectu? con la Cr?nica de Vivar, tuvo como modelos las ediciones cr?ticas realizadas por los profesores Ferreccio y Kordic en sus descripciones ling??sticas, dejando de lado la moderaci?n fonografem?tica y los aspectos literarios y referenciales por lo extenso que resultar?a un trabajo de este tipo. Para el estudio netamente ling??stico, realic? la revisi?n de la Historia del Espa?ol de Am?rica de Juan Antonio Frago, la Historia de la Lengua Espa?ola de Rafael Lapesa y la Gram?tica Hist?rica Espa?ola de Vicente Garc?a de Diego, con el fin de identificar los principales rasgos idiom?ticos meridionales presentes en la obra de Vivar; y, establec?, por contraste, los rasgos caracter?sticos del centro norte espa?ol (Burgos, lugar hipot?tico de nacimiento del autor) presentes en la Cr?nica, tomando como base fuentes sobre el espa?ol peninsular como las obras ya citadas de Lapesa y Garc?a de Diego.
9

Notabilia ling??stica de la Cr?nica de Vivar: el l?xico militar

Coloma Zurita, Leonor January 2012 (has links)
Tesis para optar al grado de Mag?ster en Ling??stica menci?n Lengua Espa?ola / La aparici?n del manuscrito de la Cr?nica de Vivar, ocurrida a mediados del siglo XX, ha significado la recuperaci?n de uno de los testimonios m?s valiosos con los que puede contar la ling??stica para dar luces acerca del espa?ol de Chile en su etapa de formaci?n. Bas?ndonos en las investigaciones que han logrado dar cuenta de la elusiva presencia de Vivar en Chile, la Cr?nica fue escrita entre los a?os 1549 y 1558, vale decir, el per?odo en que Pedro de Valdivia y sus espa?oles emprendieron la conquista, poblaci?n y sustentaci?n de las provincias del sur del continente. El valor de este documento para los estudios ling??sticos, radica en que se constituye en una muestra concreta del espa?ol que trajeron los conquistadores a Chile; primero, porque viene a ser uno de los documentos m?s tempranos escritos en nuestro territorio y, en segundo lugar, porque se trata del relato producido por el tipo de hablante que incursion? en la conquista de zonas marginales del Nuevo Mundo; vale decir, un soldado que, por lo general, no pertenec?a a la ?lite culta que se asent? en los centros de poder; todo ello permite deducir que los usos idiom?ticos del cronista son muy cercanos a lo que fueron los usos comunes de los primeros espa?oles que se establecieron en Chile.
10

Novel degradation products of ethanolamine (MEA) in CO2 capture conditions : identification, mechanisms proposal and transposition to other amines / Nouveaux produits de dégradation de l'éthanolamine (MEA) pour le captage du CO2 : identification, proposition de mécanismes et transposition à d'autres amines

Gouedard, Camille 30 September 2014 (has links)
Le captage du CO2 en postcombustion par absorption dans des solutions aqueuses d'amines est la technologie la plus mature pour réduire les émissions de gaz à effets de serre. Cependant, les amines utilisées sont susceptibles de réagir avec l'oxygène présent dans les fumées pour former de nouveaux composés qui peuvent être émis à l'atmosphère et avoir des conséquences sur l'environnement et la santé humaine.. L'objectif de cette thèse était donc d'identifier le maximum de produits de dégradation des amines grâce au développement de différentes techniques analytiques et d'échantillonnage, notamment pour l'analyse de la phase gaz. Ainsi plus de soixante produits issus de la dégradation de la monoéthanolamine (MEA) en pilote de captage du CO2 ont été identifiés. Une trentaine de ces produits sont nouveaux, ils sont souvent issus d'une même famille comme les pyrazines ou les oxazolines ou ils peuvent être caractérisés par l'allongement de la chaine carbonée (C2 entre deux hétéroatomes à C5).Des mécanismes basés sur des réactions d'alkylation/de désalkylation, la formation d'aldéhydes ou de cétones, l'amidification, l'aldolisation, la réaction d'Eschweiler Clarke, la formation de pyridines ont été proposés pour expliquer la formation de tous les nouveaux produits de dégradation et validés, dans la plupart des cas, en mélangeant les réactifs proposés dans le mécanisme. Finalement, il a été montré que la transposition de ces schémas réactionnels à trois autres amines (N-méthylaminoéthanolamine, 1-aminopropan-2-ol, 3-aminopropan-1-ol) a permis de prédire leurs produits de dégradation. / The CO2 post-combustion capture with aqueous solutions of amines is the most mature technology to reduce greenhouse gases emissions. However chemical absorption is suffering from the degradation of amines mainly due to the presence of O2 in flue gases. Formed products, which could be rejected to atmosphere, may be detrimental to environment and human health. The aim of this thesis was to identify as many degradation products as possible thanks to the development of different sampling and analytical methods especially for gas phase analysis. Thus more than sixty products issued from monoethanolamaine (MEA) degradation were observed in pilot plant samples. Thirty of them are novel, they often belong to the same family as pyrazines or oxazolines, or they could be characterized by the increase of carbon chain lengths (C2 between two heteroatoms to C5).Mechanisms such as alkylation/dealkylation, aldehydes/ketones formation, amidification, aldolisation, Eschweiler Clarke, pyridines formation were proposed to explain the formation of novel products and were, most of the time, validated by mixing the reactants proposed in the mechanism. Finally, it has been shown that the transposition of these reactions to three other amines (N-methylaminoethanolamine, 1-aminopropan-2-ol, 3-aminopropan-1-ol) enabled us to predict their degradation products.

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