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La metáfora en "Un mundo para todos divididos" /Castejón G., Leisly. January 1992 (has links)
Th. 3e cycle--Lettres--Rouen, 1978. / Bibliogr. p. 271-272. Index.
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Achieving epistemic descentCoppenger, Brett Andrew 01 July 2012 (has links)
Traditional accounts of justification can be characterized as trying to analyze justification in such a way that having a justified belief brings with it assurance of truth. The internalist offers a demanding requirement on justification: one's having a justified belief requires that one see what the belief has going for it. Externalists worry that the internalist's narrow conception of justification will lead to unacceptably radical and implausible skepticism. According to the externalist, one need not know what a belief has going for it in order for that belief to be justified. Externalism, though, comes with its own problems.
Ernest Sosa has attempted to bridge the divide between internalism and externalism by pairing the strengths of internalism (assurance) with the strengths of externalism (an answer to skepticism). Sosa distinguishes two kinds of knowledge: animal knowledge that is essentially externalist in character and reflective knowledge that is intended to capture our best intellectual procedure in regards to knowledge. On Sosa's view, one gains reflective knowledge by building upon (by adding further epistemic components to) animal knowledge. As a result, Sosa's view seems to illustrate a bottom-up approach to the analysis of knowledge (or justification): reflective knowledge is the result of animal knowledge and some other epistemic factor.
My project, in contrast to Sosa's, is to argue that one should start with an account of ideal justification (justification that is paradigmatically internalist) and then proceed by loosening the standards on ideal justification in an effort to develop the possibility of non- ideal kinds of justification. The view that I will develop will adopt Sosa's strategy of distinguishing kinds of knowledge (or justification), but will result in a top-down approach to the analysis of justification. Instead of starting with an undemanding standard and layer levels on top, I will start with an ideal standard and strip layers away.
I will also argue that my view has some important advantages over Sosa's. Not only does Sosa's view seem to run into many of the problems that threaten externalism, but his view is incapable of offering the kind of assurance that the internalist is after. The view I develop will maintain the internalist's interest in assurance while also providing a response to some of the skeptical problems that have plagued internalists.
If my project is successful, then, even if the justification that results in many of the cases I will be exploring is (admittedly) not ideal, we can use these conceptions of justification to help explicate how one might have justified beliefs about a great number of things. The essentially internalist account that I have offered will not only illustrate a serious approach to dealing with skepticism, but it will also capture how many of our commonsensically justified beliefs are in fact justified (albeit in a less than ideal sense).
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"El compositor Pedro Sosa López (1887-1953): biografía, catalogación y análisis de su obra"Sánchez Sánchez, Germán 07 March 2016 (has links)
[EN] Pedro Sosa López (1887-1953) was a composer, Harmony teacher and headmaster of the Valencia Music Conservatory. As an author, his early success, thanks to the pasodoble "Lo cant del valencià", made him a well-known person in the Valencian world of music bands, although there are lots of followers who would recognise this piece without knowing who the author was.
Within this work, we have covered every single field of Pedro Sosa, which is why we can divide it in three parts:
The first one focuses on his biography. We find his very beginnings in the city of Requena, although he soon moved to Valencia, where he was trained as a musician, mainly in the Conservatory, and later he set up his home with his wife and children.
The second part of our project focuses on his job as a teacher, where he had the chance to take part in the training of some of the Valencian musicians with the greatest prestige in the twentieth century, such as Manuel Palau, José Mª Cervera Lloret, Antón García Abril, Miguel Asins Arbó, Leopoldo Magenti, Mª Teresa Oller, José Ferriz, etc. His inclination for a well-done job, led him to get different jobs related with the Valencian musical world, becoming a leading figure in the defense of the labour rights of musicians. However, his most important role was when he managed the Conservatory of Valencia, where he carried out an important task in the modernization of the School.
The third part takes up the bulk of our work, and it is devoted to Pedro Sosa's work as a composer. First of all, we have focused on cataloguing all his production. A later comprehensive analysis of each of his works has allowed us to understand his composition style through the musical language he used and to place him in a suitable historical time. Following at the beginning the path shown by Salvador Giner (1832-1911), we discover that Sosa is inspired by the Valencian folklore, although the use of a more advanced musical language lets him approach impressionist styles. / [ES] Pedro Sosa López (1887-1953) fue compositor, profesor de armonía y director del Conservatorio de Valencia. Como autor, su temprano éxito, gracias al pasodoble Lo cant del valencià, lo convirtió en una persona conocida en el ámbito valenciano de las bandas de música, aunque son muchos los aficionados que reconocerían esta obra sin saber quién fue su autor.
En este trabajo, hemos querido abarcar todos los ámbitos de la figura de Pedro Sosa, por lo que podemos dividirlo en tres bloques:
El primero de ellos se centra en su biografía. Encontramos sus orígenes en la ciudad de Requena, aunque se trasladó pronto a Valencia, donde se formó como músico, principalmente en el Conservatorio, y estableció posteriormente su domicilio familiar junto a su esposa e hijos.
El segundo bloque de nuestro trabajo se centra en su labor profesional como docente, en la que tuvo la oportunidad de contribuir a la formación de algunos de los músicos valencianos de mayor proyección del siglo XX, como son Manuel Palau, José Mª Cervera Lloret, Antón García Abril, Miguel Asins Arbó, Leopoldo Magenti, Mª Teresa Oller, José Ferriz, etc. Su predisposición hacia el trabajo bien hecho, lo llevaron a ocupar diferentes cargos relacionados con la vida musical valenciana, convirtiéndose en una figura señalada en la defensa de los derechos laborales de los músicos. Pero el cargo más significativo que ocupó fue la dirección del Conservatorio de Valencia, donde realizó una labor importante de modernización del centro.
El tercer bloque constituye el grueso de nuestro trabajo, y está dedicado a la obra compositiva de Pedro Sosa. En primer lugar hemos realizado la catalogación de toda su producción. Un posterior análisis exhaustivo de cada una de las piezas, nos ha permitido comprender su estilo compositivo a través del lenguaje musical que utilizó y colocarlo en el lugar histórico que le corresponde. Siguiendo inicialmente el camino marcado por Salvador Giner (1832-1911), encontramos que Sosa se inspira en el folclore valenciano, pero la utilización de un lenguaje musical más avanzado le permite acercarse a posturas impresionistas. / [CA] Pedro Sosa López (1887-1953) va ser compositor, professor d'harmonia i director del Conservatori de València. Com a autor, el seu enjorn èxit, gràcies al pasdoble Lo cant del valencià, ho va convertir en una persona coneguda en l'àmbit valencià de les bandes de música, encara que són molts els aficionats que reconeixerien esta obra sense saber qui va ser el seu autor.
En este treball, hem volgut comprendre tots els àmbits de la figura de Pedro Sosa, per la qual cosa podem dividir-ho en tres blocs:
El primer d'ells se centra en la seua biografia. Trobem els seus orígens en la ciutat de Requena, encara que es va traslladar prompte a València, on es va formar com a músic, principalment en el Conservatori, i va establir posteriorment el seu domicili familiar junt amb la seua esposa i fills.
El segon bloc del nostre treball se centra en la seua labor professional com a docent, en la que va tindre l'oportunitat de contribuir a la formació d'alguns dels músics valencians de major projecció del segle XX, com són Manuel Palau, José Mª Cervera Lloret, Antón García Abril, Miguel Asins Arbó, Leopoldo Magenti, Mª Teresa Oller, José Ferriz, etc. La seua predisposició cap al treball ben fet, ho van portar a ocupar diferents càrrecs relacionats amb la vida musical valenciana, convertint-se en una figura assenyalada en la defensa dels drets laborals dels músics. Però el càrrec més significatiu que va ocupar va ser la direcció del Conservatori de València, on va realitzar una labor important de modernització del centre.
El tercer bloc constituïx el gros del nostre treball, i està dedicat a l'obra compositiva de Pedro Sosa. En primer lloc hem realitzat la catalogació de tota la seua producció. Una posterior anàlisi exhaustiva de cada una de les peces, ens ha permés comprendre el seu estil compositiu a través del llenguatge musical que va utilitzar i col¿locar-ho en el lloc històric que li correspon. Seguint inicialment el camí marcat per Salvador Giner (1832-1911) , trobem que Sosa s'inspira en el folklore valencià, però la utilització d'un llenguatge musical més avançat li permet acostar-se a postures impressionistes. / Sánchez Sánchez, G. (2016). "El compositor Pedro Sosa López (1887-1953): biografía, catalogación y análisis de su obra" [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/61477
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Fracture characterization in magmatic rock, a case study of the Sosa-dyke (Neuquén Basin, Argentina) / Spricknätverkskarakterisering i magmatiskt berg, en fallstudie om Sosa-intrusionen (Neuquén Basin, Argentina)Jim, Nilsson January 2020 (has links)
There are many examples worldwide were fossil magmatic intrusions influence the local water and energy supply. Due to that intrusions can act as a conductor and a reservoir, but also as a barrier for fluids and gases in the ground. The decisive feature between conductor or barrier in an intrusion is its fracture network. Hence it is of paramount importance to characterize an intrusion’s fracture network and thus its permeability. However, other than through boreholes magmatic intrusions are rather inaccessible and very little is known about their influence on aquifers and reservoir rocks in the underground. It is therefore important to increase the knowledge of magmatic intrusion by investigate the intrusions that are accessible for us at ground surface. In this study, photos from a case study about the Sosa dyke have been used to map and characterizes the fractures of the Sosa dyke, which is an accessible vertical magmatic intrusion and a part of the Chachahuén volcano complex in the southwestern parts of Argentina. The photos that were used are taken with an UAV (unmanned aerial vehicle), and to analyze the photos, map the fractures and produce the results, software as Agisoft Metashape, MOVE™ and MATLAB with the toolbox FracPaQ was used. The intrusion has two distinct fracture sets, one that is perpendicular to the intrusion margins and one that stretches parallel with the intrusion. The connectivity of the fractures is low, and since the permeability of the fractures largely depends on the connectivity, it is also low. The fracture set that is perpendicular to the intrusion margin is what’s called cooling fractures, which is created as the magma in the intrusion cools. This causes the magma to contract and break, forming fractures perpendicular to the inward migrating solidification front. The fracture set that is parallel with the intrusion is caused by minerals in the magma flow being affected by friction from the intrusion margins. This causes the minerals in the magma to elongate in the direction of flow along the sides of the dyke, creating foliation, enabling fractures to propagate along. These fracture sets are poorly connected which concludes that the mapped area of the Sosa-dyke has a low permeability. / I hela världen finns det många exempel där stelnade magmatiska intrusioner påverka ett områdes vatten och energiförsörjning, på grund av att intrusioner kan agera som ledare och reservoarer men också som barriärer för vätskor och gaser in marken. Den avgörande faktorn mellan ledare och barriärer i en intrusion är dess spricknätverk. Därför är det viktigt att kartlägga och karakterisera en intrusions spricknätverk och därmed också få en uppfattning om dess permeabilitet. Magmatiska intrusioner är förutom genom borrhål ofta svåråtkomliga, det finns därför väldigt lite information om hur de påverkar akviferer och reservoarer i marken. Det är därför viktigt att öka kunskapen om magmatiska intrusioner genom att undersöka intrusionerna som är tillgängliga vid markytan. I denna studie har bilder från en fallstudie om Sosa Intrusionen använts för att kartera och karakterisera sprickor i Sosa intrusionen. Det är en vertikal magmatisk intrusion som är synlig på markytan, och en del av Chachahuén vulkan komplexet i sydvästra Argentina. Bilderna som användes är tagna med en UAV( unmanned aerial vehicle), och för att analysera bilderna, kartera sprickorna och producera resultaten, användes programmen Agisoft Metashape, MOVE™ och MATLAB med FracPaQ verktyget. Intrusionen har två distinkta sprickgrupper, en som är vinkelrät mot intrusionens kanter och en som går parallellt med kanterna. Konnektivitet mellan sprickorna är låg och eftersom permeabiliteten påverkas av konnektiviteten är den också låg. Sprickgruppen som är vinkelrätt mot intrusionskanten är så kallade kylningssprickor och bildas nät magman i intrusionen svalnar. Det leder till att magman kontraherar och spricker, och bildar sprickor som går inåt mot stelningsgränsen och därmed vinkelrätt mot intrusionskanten. Sprickgruppen som går parallellt med intrusionen bildas av att mineral i magmaströmmen påverkas av friktion från intrusionskanterna. Det gör att mineralen lägger sig och sträcks ut i samma riktning som magmaflödet, vilket när magman stelnar bildar svaghetszoner som sprickor kan fortplanta sig i. Dessa sprickgrupper har låg konnektivitet vilket gör att slutsatsen blir att det karterade området av Sosa intrusionen har låg permeabilitet.
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DOC-Quellstärke (Phase 1): Entstehung, Freisetzung und Transport von gelöstem organischen Kohlenstoff (DOC) in bewaldeten Einzugsgebieten am Beispiel der Trinkwassertalsperre Sosa: Ergebnisse der Phase 1 des Forschungsvorhabens (07/2019 bis 07/2023)Kalbitz, Karsten, Houska, Tobias, Krüger, Stephan, Krause, Tobias, Jackisch, Conrad, Lau, Maximilian, Petzold, Rainer, Brösing, Marc, Brückner, Daniel, Möller, Annika, Müller, Ingo 25 June 2024 (has links)
Die Schriftenreihe informiert über Forschungsergebnisse zur Entstehung und Transport von gelösten organischen Kohlenstoffverbindungen (DOC, dissolved organic carbon) im Einzugsgebiet der Talsperre Sosa.
DOC entsteht in den Humusauflagen der Wälder, in degradierten Mooren und in mineralischen Böden. Es wird insbesondere bei Starkregen und während der Schneeschmelze ausgetragen. Der Eintrag in die Gewässer hängt ab von der Freisetzung des DOC, von der Fließverbindung des Bodenwassers und von Rückhalteprozessen im Boden. Hieraus ergeben sich mögliche Optionen zur Verminderung des DOC-Eintrags in Trinkwassertalsperren, da DOC hier erhebliche Probleme verursacht. Die Veröffentlichung richtet sich an Forschungseinrichtungen, Fach- und Vollzugsbehörden und interessierte Bürgerinnen und Bürger.
Redaktionsschluss: 30.09.2023
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Spectroscopic Study of Highly Ionised Plasmas : Detailed and Statistical Approaches / Etude spectroscopique des plasmas hautement ionisés : approche détaillée et statistiqueNa, Xieyu 16 November 2017 (has links)
La description des propriétésspectrales des plasmas hautement ionisés –comme ceux rencontrés en fusion nucléaire,en astrophysique et en expérimentationlaser-plasmas –peut nécessiter différentstypes d’interprétation, parmi lesquelsl’approche détaillée ou raie-par-raieimpliquant de la diagonalisation del’Hamiltonien du système et, l’approchestatistique basée sur la caractérisation desstructures spectrales à travers les momentsde distribution.Ce travail de thèse a pour objectif d'étudier etde mettre en œuvre les méthodes statistiquestraitant des cas où de nombreuses raies seregroupent en faisceaux de transition nonrésolus (UTA pour Unresolved TransitionArray).Pour cela, des études analytique et numériqueont été menées. D’une part, les momentsd’ordre élevé de la distribution d’énergies spinorbiteont été obtenus, en utilisant lestechniques de calcul de moyennes qui fontintervenir les résultats de la secondequantification et de l’algèbre de momentangulaire. D’autre part, après avoir implémentéun programme de post-traitement des donnéesatomiques produites par le code FAC (FlexibleAtomic Code), en mode détaillée comme enmode UTA, les spectres d’émission et / The description of spectralproperties of highly ionized plasmas – asthose studied in stellar atmospheres, facilitiesfor nuclear fusion, or laser-plasmasexperiments – may require different types ofinterpretation, among which the detailed line by-line accounting which relies on Hamiltoniandiagonalization and the statistical approachbased on the characterization of spectralstructures through distribution moments.My PhD work aims at developing statisticalmethods dealing with situations whereabundant lines gather in Unresolved TransitionArrays (UTA).To this end, analytical and numerical analysishave been carried out. On one hand, high-ordermoments of spin-orbit energy have beenderived using averaging calculation techniquesbased on second quantization results andangular momentum algebra. On the other hand,after implementing a post-processing programfor both detailed and UTA computations of theFlexible Atomic Code (FAC), emission andabsorption spectra of tungsten plasmas havebeen studied in tokamak-equivalentthermodynamic conditions.Results of this thesis should hopefully stimulatefurther analysis on averages computationinvolving complex transition processes.
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An Analysis and Performance Guide of Selected Works for Saxophone by Cuban Composers Jorge Luis Sosa and Andrés Alén-RodriguezFriel, Stephan 08 1900 (has links)
A large portion of the standard repertoire for saxophone and piano has already been recorded and performed many times and has received significant scholarly study. For a performer, remaining relevant requires learning and performing new compositions. Jorge Sosa and Andrés Alén are both accomplished composers, yet outside of the Latin-American community they remain virtually unknown to most saxophonists. This project serves as an introduction to both composers. Combined, Sosa and Alén have nine compositions for saxophone. Their works include saxophone quartets, saxophone and piano, and saxophone quartet with choir. This study focuses on three compositions: La Zacapaneca by Sosa, Tema con Variaciones and Sonata para Clarinete ó Saxofón Soprano y Piano, both by Alén. Compositional background information is given about each composition to include date of composition, premiers, important recordings, length of performance and Cuban ethnic and traditional elements used as the basis for rhythmic and thematic ideas. The Cuban and Afro-Cuban influences are explained in further detail pertaining to how they were used in the construction of the works and in their being performed stylistically correctly. Dynamics, articulations, and performance considerations are studied at length.
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Virtue epistemology and the analysis of knowledgeChurch, Ian M. January 2012 (has links)
This thesis centers on two trends in epistemology: (i) the dissatisfaction with the reductive analysis of knowledge, the project of explicating knowledge in terms of necessary and jointly sufficient conditions, and (ii) the popularity of virtue-theoretic epistemologies. The goal of this thesis is to endorse non-reductive virtue epistemology. Given that prominent renditions of virtue epistemology assume the reductive model, however, such a move is not straightforward—work needs to be done to elucidate what is wrong with the reductive model, in general, and why reductive accounts of virtue epistemology, specifically, are lacking. The first part of this thesis involves diagnosing what is wrong with the reductive model and defending that diagnosis against objections. The problem with the reductive project is the Gettier Problem. In Chapter 1, I lend credence to Linda Zagzebski's grim 1994 diagnosis of Gettier problems (and the abandonment of the reductive model) by examining the nature of luck, the key component of Gettier problems. In Chapter 2, I vindicate this diagnosis against a range of critiques from the contemporary literature. The second part involves applying this diagnosis to prominent versions of (reductive) virtue epistemology. In Chapter 3, we consider the virtue epistemology of Alvin Plantinga. In Chapter 4, we consider the virtue epistemology of Ernest Sosa. Both are seminal and iconic; nevertheless, I argue that, in accord with our diagnosis, neither is able to viably surmount the Gettier Problem. Having diagnosed what is wrong with the reductive project and applied this diagnosis to prominent versions of (reductive) virtue epistemology, the final part of this thesis explores the possibility of non-reductive virtue epistemology. In Chapter 5, I argue that there are three strategies that can be used to develop non-reductive virtue epistemologies, strategies that are compatible with seminal non-reductive accounts of knowledge and preserve our favorite virtue-theoretic concepts.
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Race on first, class on second, gender on third, and sexuality up to bat intersectionality and power in Major League Baseball, 1995-2005 /Alexander, Lisa Doris. January 2006 (has links)
Thesis (Ph.D.)--Bowling Green State University, 2006. / Document formatted into pages; contains viii, 186 p. Includes bibliographical references.
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Síntesis de carboximetilcelulosa (CMC) a partir de pastas de plantas anualesBarba Pacheco, Claudia 28 June 2002 (has links)
Palabras clave: materiales lignocelulósicos residuales, chopo, pino, paja de trigo, plantas anuales, abacá, sisal, yute, lino, Miscanthus sinensis, bagazo de caña de azúcar, henequén, pastas de cocción rápida sosa/AQ, pastas IRSP, carboximetilcelulosa, comportamiento reológico, grado de sustitución.El presente trabajo describe la preparación y caracterización de muestras de carboximetilcelulosa (CMC) a partir de diferentes materiales lignocelulósicos tanto residuales como no madereros, así como el estudio de la influencia de las condiciones de preparación de la materia de partida y sus características sobre las propiedades finales de las CMCs obtenidas. La producción de carboximetilcelulosa a partir de estos materiales supone una importante contribución ya que, en la mayoría de los casos, el derivado se obtiene a partir de linters de algodón y madera de pino y eucalipto. Las muestras de CMC fueron preparadas a partir de pastas procedentes de tres diferentes tipos de cocciones:  Pastas blanqueadas de pino, chopo y paja de trigo, provenientes de procesos de cocción con sosa/antraquinona con tiempos de residencia que abarcaban desde los convencionales de aproximadamente 90 min hasta tiempos de cocción rápidos del orden de 3 min. Pastas blanqueadas de Miscanthus sinensis, bagazo de caña de azúcar y henequén cocidas mediante el método IRSP (Impregnation Rapid Steam Explosion Process) Pastas papeleras comerciales y blanqueadas provenientes de procesos convencionales sosa/antraquinona de abacá, sisal, yute y lino La reacción de eterificación se llevó a cabo siguiendo el procedimiento Druvacell a escala laboratorio para la obtención de CMC con alto grado de pureza. Esta se realizó utilizando siempre las mismas condiciones de operación y relación cuantitativa de los materiales presentes. Los productos purificados fueron caracterizados en función de su grado de sustitución (DS), pureza, solubilidad, viscosidad intrínseca  de soluciones de CMC en NaCl 0.1M, peso molecular y comportamiento reológico de soluciones de CMC a diferentes concentraciones. Se encontró que el DS de las CMCs sintetizadas en el laboratorio dependen en gran medida de la morfología del material lignocelulósico del cual provienen. El método usado para la eterificación de las pastas, da como resultado DS cercanos a 1 después de una eterificación y alrededor de 2 si se aplica un segundo tratamiento de eterificación. Con excepción de las CMCs fabricadas a partir de Miscanthus sinensis y bagazo de caña de azúcar, se obtuvieron DS de 0.75 y 1.45 después de una y dos eterificaciones respectivamente. La pureza de todas las muestras de CMC superaba el 98%. Los valores del peso molecular y el comportamiento reológico de las soluciones de CMC están relacionados con la viscosidad de las pastas de partida. De esta manera, las pastas que tenían un valor menor de viscosidad generaban CMCs con un comportamiento reológico cercano al newtoniano y por el contrario las CMCs que fueron sintetizadas a partir de pastas con mayor viscosidad, presentaban comportamientos pseudoplásticos. Los resultados relacionados con la caracterización reológica de las muestras de CMC, muestran que es posible obtener derivados de celulosa de pastas no madereras con propiedades diferentes a las obtenidas por materiales comunes como la madera o linters de algodón. Estos nuevos materiales presentan un potencial importante para la producción de derivados de celulosa con características innovadoras para aplicaciones industriales específicas, especialmente la estabilidad de la viscosidad con la temperaturaEn general, los experimentos realizados mostraron la viabilidad de obtener CMCs similares a las comerciales partiendo de materiales no convencionales. Además, se confirma la posibilidad de producir derivados de celulosa a partir de pastas de cocción rápida y explosión con vapor, ampliándose de esta manera las opciones de estudio de otros derivados de celulosa de interés industrial. / Keywords: waste lignocellulosic materials, poplar, pine, wheat straw, annual plants, abaca, sisal, jute, linen, Miscanthus sinensis, sugar cane, henequen, fast soda/AQ pulps, IRSP pulps, carboxymethylcellulose, rheological behavior, degree of substitution.In this manuscript we describe the synthesis and characterization of carboxymethylcellulose (CMC) samples from different lignocellulosic residual and non-wood materials. We also describe how the condition of the raw materials affects the preparation and final properties of the CMCs produced. The production of carboxymethylcellulose from these materials is an important contribution because, currently, it is produced from cotton linters and pine and eucalyptus wood.The CMC samples were prepared from three kinds of cellulose pulps:  Soda/anthraquinone bleached pine, poplar and wheat straw pulps with cooking residence times ranging from 3 to 90 min. Steam exploded Miscanthus sinensis, sugar cane and henequen pulps cooked by IRSP (Impregnation Rapid Steam Explosion Process). Commercial bleached paper pulps cooked by the soda/anthraquinone process of abaca, sisal, jute and linen.High purity carboxymethylcellulose was obtained by the etherification Druvacell process on a laboratory scale, always under the same conditions and with the same chemical amounts.The final purified products were characterized in terms of their degree of substitution (DS), purity and solubility in concentrated NaOH, CMC intrinsic viscosity  in 0.1M NaCl solutions, molecular weight and rheological behavior of CMC samples at different concentrations.We found that the DS depended on the raw material morphology and properties and not on the cooking temperature of the pulp source. The method we used for the etherification reaction yielded CMCs whose degree of substitution was close to 1 after one etherification reaction, and around 2 when a second etherification reaction was performed at the same conditions. Miscanthus sinensis and sugar cane were the only exceptions because they yielded CMCs with a DS of around 0.75 and 1.45 after one and two etherification treatments. All CMC samples had purities of over 98%. The molecular weights and the rheological behavior of the CMC solutions were directly related to the viscosity of the pulps. Pulps of lower viscosity therefore produced CMCs whose rheological behavior was similar to Newtonian behavior. On the other hand, the pseudoplastic behavior was obtained from pulps of higher viscosity.The rheological characterization of the CMC samples shows the viability of obtaining carboxymethylcellulose from non-conventional materials whose characteristics are different from those obtained from common materials such as wood or cotton. These new materials have great potential for producing cellulose derivatives with novel characteristics like temperature stability that make them suitable for specific and tailor-made industrial applications. Overall, our results show that carboxymethylcelluloses can be obtained from non-conventional materials having similar characteristics to commercial CMC. We also confirm the production of CMC from rapid soda/AQ and IRSP pulps, being posible to extend this study for other cellulose derivatives of industrial interest.
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