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El presente artículo es un análisis del relato «Gubi Amaya», de la escritora argentina Juana Manuela Gorriti. Dicho análisis se basa en la estructuración externa del relato, así como en la configuración de su mundo representado, vinculado con el contexto de la literatura gótica y el romanticismo. A partir de dicho vínculo, se busca demostrar que el relato en cuestión se identifica con una tendencia fantástica a partir de la categoría de superstición. El marco teórico empleado destaca la caracterización de lo fantástico como estrategia para la revelación del pensamiento supersticioso. Así, un elemento clave para entender esta propuesta estético-ideológica es la recuperación del mundo perdido de la infancia por parte de la narradora. Dicha recuperación, y el efecto fantástico que ello conlleva, se logra a través de un viaje espacio-temporal como posible llave del enigma en el relato. Ahora bien, se expresa a su vez un desdoblamiento del personaje que da título al texto, lo que conduce a la noción del doble como prototipo de la literatura fantástica. Para esclarecer este fenómeno paranormal, se emplea el concepto freudiano de lo siniestro, a partir de lo cual se busca aclarar si el accionar de la narradora en su búsqueda del pasado forma parte de la realidad o del mundo del sueño.

La narrativa peruana de Ventura García Calderón, inscrita en el contexto estético-literario del indianismo modernista, generó una gran polémica en su relación con el proyecto político-cultural del Indigenismo en las primeras décadas del siglo xx en nuestro país. El presente artículo busca reflexionar en torno a este debate, centrándose en algunos cuentos de su libro La venganza del cóndor (1924), de los alcances narrativos de este autor en torno a lo fantástico y lo maravilloso, así como su singular posición en torno al proyecto indigenista.

Numerous studies explored the possibility and effective strategies for supplementing hydrogen along with fossil or biofuels on internal combustion engines. Hydrogen is also being employed for formulating fuels such as hydrogen compressed natural gas in the gaseous form and hydrogenated biofuels in the liquid form. The present study evaluates (i) hydrogen usage on the fuel formulation and (ii) investigates the engine operation of an automotive turbocharged diesel engine operated with karanja biodiesel blended diesel (B20) as a reference fuel. Existing literature outlines that biodiesel blends possess lower energy content and emit higher nitric oxide (NO) emission than fossil diesel. The present research paper partially hydrogenates karanja biodiesel using an autoclave reactor with a palladium catalyst to increase the saturation levels and mitigate the biodiesel-NO penalty. Besides, the drop in energy release of B20 is compensated through the provision of hydrogen induction along the intake manifold. The hydrogen flow rates to the turbocharged engine are maintained at a fixed energy share of 10%. Both biodiesel and hydrogenated biodiesel were blended on a volume basis (20%) with fossil diesel (80%) and are designated as B20 and HB20, respectively. The test results reveal that HB20 effectively mitigates the biodiesel-NO penalty with a maximum reduction of 29.8% compared to B20. Further, hydrogen induction yielded a significant improvement (23.7%) in fuel consumption with HB20 relative to B20 without hydrogen addition. The compounding effect of hydrogen usage on the engine operation and fuel formulation exhibited a better performance and emission trade-off at mid load conditions.

There has been extensive research on efficient energy conversion systems which also includes turbocharging the automotive SI engine. This research focuses on comparing the thermodynamic aspects of the turbine at different boost pressures at maximum engine torque and speed regions. A naturally aspirated CNG SI engine developing 15.5 kW at 3400 rpm was converted to a turbocharged LPG engine at the compression ratio of 8.5:1. The turbine performance was evaluated using ANSYS CFX numerical simulation tool and results were validated. The simulation study reveals that 1.3 bar boost pressure has a higher enthalpy generation and also has minimal Mach number than 1.5 bar signifying the effects of exhaust blowdown. Further, the experimental study was carried out at different boost pressures. The results show that at 1.3 bar, the turbine efficiency was higher with reduced heat transfer rate to the compressor which was due to reduced friction work compared to 1.5 bar which altogether improved the engine performance. This is also evident from the minimal COV of IMEP for 1.3 bar. On the whole, the turbine exhibited better performance for 1.3 bar and resulted in reduced thermal loading.

ilustraciones The chiral molecule interactions depend on their chirality. Important molecules of life such as proteins, enzymes, amino acids, carbohydrates, and so on, are chiral. Chiral substances which interact with them, such as drugs and agrochemicals, must present a specific enantiomeric content to assure effectiveness. Thus, whereas one enantiomer of a chiral drug or agrochemical product has a desired effect, the other one may be inactive or even toxic. The study of methods to identify the enantiomeric content of chiral substances is a current research topic. Although there are a wide variety of methods, which generally demand expensive reagents, large equipment, and the need for highly qualified personnel, new techniques are still in demand due to the continuous development of new chiral substances, and the industrial need to perform millions of tests during short periods of time. In this scenary, methods based on optical waveguide structures present a great potential, providing great sensitivity, real-time monitoring, and no invasiveness. For this reason, in this M.Sc. thesis, a theoretical and numerical study of optical waveguides involving chiral media is presented. The study is centered around planar symmetric and asymmetric waveguides, where the effects of the real, and for the first time, the imaginary part of the chirality parameter are analyzed in the characteristics of the guided light. As an application of the study, a lossy mode resonances (LMR) based optical fiber sensor is designed to measure the chirality parameter. (Tomado de la fuente) Las interacciones de moléculas quirales dependen de su quiralidad. Las moléculas importantes para la vida como proteínas, enzimas, aminoácidos, carbohidratos, etc., son quirales. Las sustancias quirales que interactúan con ellas, como fármacos y agroquímicos, deben poseer un contenido enantiomérico específico para asegurar su efectividad. De esta manera, mientras un enantiómero de un fármaco quiral o un agroquímico quiral produce los efectos deseados, el otro podría ser inactivo o incluso tóxico. El estudio de los métodos para identificar el contenido enantiomérico de sustancias quirales es un área de investigación actual. A pesar de que hay una amplia variedad de métodos, los cuales generalmente demandan reactivos caros, equipos de gran tamaño y la necesidad de personal altamente calificado, se demandan nuevas técnicas debido al continuo desarrollo de sustancias quirales y la necesidad industrial de llevar a cabo millones de pruebas en cortos periodos de tiempo. En este escenario, los métodos basados en guías de onda ópticas presentan un gran potencial, ofreciendo gran sensibilidad, monitoreo en tiempo real y no invasibidad. Por esta razón, en esta tesis de maestría en ciencias se presenta un estudio teórico y numérico de guías de onda óptica con medios quirales. El estudio se centra en guías de onda planas simétricas y asimétricas, donde se analizan los efectos de la parte real, y por primera vez, la parte imaginaria del parámetro de quiralidad sobre la luz guiada. Como una aplicación del estudio, se diseña un sensor basado en resonancias de modos con pérdidas en fibra óptica para medir el parámetro de quiralidad. (Tomado de la fuente) Maestría Magíster en Ciencias - Física Fotónica

This work focuses on the numerical and experimental analysis of turbocharger selection and boost pressure effects on a CNG-fueled spark-ignition engine. Because of this, investigations are carried out on the influence of downsized compression ratio of 10.5:1 at different boost pressures and compared with a naturally aspirated compression ratio of 12.5:1. In order to perform the experimentation, a twin-cylinder, port fuel-injected, CNG engine with 15.5 kW at 3400 rpm is modified to utilize compressed bio-methane as fuel under 100% throttle condition. A simulation is performed to study the compressor impeller for T1 and T2 turbochargers using the ANSYS turbomachinery tool. Results indicate that the circumferential velocity of T1 is higher than of T2 at all boost pressures. Subsequently, experimentation is performed using T1 and T2 at three different boost pressure levels in a compression ratio of 10.5:1 at 1.1, 1.3, and 1.5 bar. T2 developed a maximum boost pressure of 1.1 bar compared to T1. T1 is chosen for further experimentations. At 1.3 bar of boost pressure, a rise in brake power was recorded by 19.3% compared to 12.5:1 under the naturally aspirated mode. Consequently, there is a reduction in fuel consumption by 10.1%, and hydrocarbon, carbon monoxide, and carbon dioxide emission levels reduce by 25%, 8.2%, and 4.9%, respectively. Therefore, turbocharging at a lower compression ratio exhibits better performance and reduces emissions compared to a higher compression ratio under naturally aspirated mode.

The effects of turbocharger wastegate actuator upon engine performance and emission were experimented on a twin-cylinder spark-ignited engine fuelled by gas phase LPG. The load was given by setting the throttle wide open and the speed was varied from 1000 to 3400 rpm. Taking the base reference as naturally aspirated conditions, various performance and emission parameters were compared for the conventional wastegate system as well as electronic version focusing on manifold absolute pressure, knock and exhaust resistance. The manifold absolute pressure and wastegate position were calibrated for the electronic wastegate to optimally perform based on engine requirements. There was appreciable improvement in brake thermal efficiency as well as reduction of unburnt hydrocarbon emissions for the turbocharger with electronic wastegate.

The current rate of depletion of fossil fuels has created an imbalance in the energy exchange. Stricter emission standards are enforced in order to control the environmental pollution and global warming. Both these factors have led to a shift from usage of conventional fossil fuels to other alternative resources. LPG serves as a viable alternative option owing to its suitability to fuel SI engines and its obtainability from large scale shale gas reserves. Being a gas at atmospheric condition, it offers proper homogenization and is best suited for lean-burn conditions. Adding methanol in small amount to LPG lowers the combustion temperature due to the latent heat of vaporization and improves lean operation due to oxygen content contributing in reduction of NOx. This work is focused on NOx reduction as it is hazardous and main constituent in the formation of PM, smog and acid rains. An experimental study is conducted in a single cylinder diesel engine modified to operate as SI engine at an optimized compression ratio of 10.5:1 and 1500 rpm fueled by LPG. The effects of methanol substitution were investigated in reduction of NOx emissions at 100% throttle condition by injecting 10, 20 and 30% of methanol on energy basis into the intake port of engine. The results have been analyzed with Brake Effective Mean Pressure (BMEP) as it serves as an important yardstick to compare different criteria. The experiments were performed at BMEPs of 4, 4.5,5 and 5.5 bar. There is a significant improvement in brake thermal efficiency along with decrease in the NOx emission as the percentage of methanol in the fuel goes higher. The decrease in NOx is significant ranging from 83% at 4 bar BMEP to 12% at 5.5 bar. The lean operation was also improved on addition of methanol.

The effects of carburetion and port fuel injection (PFI) metering techniques were experimented on naturally aspirated twin-cylinder spark-ignited (SI) engine fuelled with compressed natural gas (CNG). It was operated under full throttle condition at varying speeds ranging from 920 to 3400 rpm for the compression ratio 11.5:1. The performance, emission and combustion parameters were assessed and compared. The carburetion was set at 0.9 bar, while the PFI was set to 5 bar working pressure. A dedicated electronic control unit (ECU) was used for controlling the engine parameters. Comparing with carburetion, the PFI produced maximum brake thermal efficiency of 27.2% at 1800 rpm. Due to the increased volumetric efficiency performance of PFI system, there was notable reduction in hydrocarbon (HC) as well as carbon monoxide (CO) emissions in comparison with carburetion. There was a noticeable increase in nitric oxide (NO) emission as a result of complete combustion. The enhanced combustion process with PFI has improved peak pressure with reduced cyclic variations. On a whole, PFI system had excelled carburetion system towards better mixture formation.

The performance and emission characteristics of LPG fuelled SI engine is determined by efficient combustion. This depends on the in-cylinder motion of intake homogenous charge generated by combustion chamber geometry. The inherent, unsteady, turbulent motion of the mixture helps in flame propagation which in turn enhances the combustion rate. Compression ratio, charge squish velocity and turbulent kinetic energy are responsible for stable combustion and laminar flame propagation. The in-cylinder charge motion is generally described by swirl, squish, tumble and turbulence which have a vital role on air-fuel mixing and combustion. The piston geometry helps in aiding in-cylinder motion for reducing fuel consumption and enhancing the combustion parameters. In particular, piston squish area in combustion chamber geometry has a major influence in charge motion inside the combustion chamber. The effect of piston squish area on charge motion was studied by CFD using STAR-CD with 25%, 30%, 35% and 40% squish areas to optimize piston crown geometry. Experiments were also conducted with above squish area pistons at a compression ratio of 10:1 to validate the CFD study. It was found that 30% piston squish area improved the performance, combustion characteristics and reduced the emission with LPG fuelled lean burn SI engine.

This study discusses the effects of addition of small amount of alcohols on performance and emission behaviour of a gasoline fuelled lean burn SI engine. Experiments were carried out in a single cylinder diesel engine, which is made to operate as SI engine on lean condition with gasoline as a fuel. The engine was operated at wide open throttle at a compression ratio of 10.5:1 and 1,500 rpm at diverse equivalent ratios by injecting the fuel into manifold. The test outcomes stipulate that use of ethanol-gasoline blend (10% by volume) was better compared with methanol-gasoline blend (10% by volume) and pure gasoline. The test results also revealed that there was 2.5% and 7.5% improvement in brake thermal efficiency with M10 and E10 blends and apparent extension in the lean limit of operation with alcohol-gasoline blends. In emission front, reduction in hydrocarbon and carbon monoxide emissions were observed. However, carbon dioxide and nitric oxide emissions were increased due to better combustion and high in-cylinder temperature. On the whole it is concluded that small alcohol addition to gasoline improves performance and reduce emissions for lean operating SI engine.

The final-focus system demagnifies the beams down to nanometer sizes in order to achieve the nominal luminosity. Such a delicate system is sensitive to imperfections and the process of bringing the imperfect system to nominal performance is called tuning. In this report we consider static imperfections and a tuning procedure consisting of beam-based alignment for correction of the linear system followed by sextupole alignment and tuning knobs for the sextupole and octupole magnets.

Analiza el proceso de la poesía peruana desde fines del siglo XIX hasta inicios del XX, en relación con la asimilación y el diálogo que los poetas peruanos de dicho periodo establecieron con los escritores simbolistas franceses. En ese sentido, partimos de la siguiente problemática: ¿cuáles son los aspectos estéticos e ideológicos que vinculan el Simbolismo francés con la propuesta poética de autores como Nicanor della Rocca de Vergalo, Manuel González Prada y José María Eguren principalmente, y en qué medida dicho vínculo se manifiesta en relación con movimientos vinculantes con la propuesta simbolista como el Romanticismo, el Parnasianismo, el Decadentismo o el Modernismo? Realiza un análisis de los principales movimientos, escuelas y, en general, propuestas artístico-literarias que destacaron en Francia a fines del siglo XIX: Parnasianismo, Decadentismo, Simbolismo, etc., con el objetivo de tener una noción mucho más clara lo que entendemos por poesía simbolista. En ese sentido, se configura un léxico operativo que nos permitirá movernos con mayor seguridad dentro de los distintos fenómenos literarios que abordaremos a lo largo de los siguientes capítulos. Además, se analiza el proceso de difusión de los simbolistas en Perú desde 1880 hasta 1920: iniciadores como Baudelaire, maestros como Verlaine, Rimbaud o Mallarmé, así como quienes formaron parte de la llamada escuela simbolista (Moréas, Laforgue o Kahn). Ello, a partir de la revisión de periódicos y revistas de la época en que hayan aparecido poemas, en el idioma original o traducciones, así como artículos y diversos estudios sobre ellos en nuestro país. También se evalúa la difusión de libros y revistas vinculados al Simbolismo que hayan venido del extranjero, tanto en su versión original como en traducciones. Se analiza la propuesta poética de Nicanor della Rocca de Vergalo, en especial su proyecto de establecer reformas en la tradición poética francesa (teóricamente, a partir de su tratado La poétique nouvelle, y en la práctica, con colecciones de poemas como Feuilles du cœur y Le livre des Incas). A decir de ciertos estudiosos, algunas de estas reformas se entienden como una suerte de anticipo del verso libre, elemento esencial en el desarrollo del Simbolismo. A ello le sumaremos el estudio de su poesía “peruana”, es decir, se abordar las implicancias estéticas e ideológicas de textos cuyo contenido tiene como marco de referencia aspectos de la cultura peruana como los periodos incaico o colonial (sobre todo en Le livre des Incas), así como la composición de sus “yaravíes”, escritos 20 exclusivamente en francés aunque relacionados en cierta medida con una tradición “híbrida” que combina los elementos andinos con los hispanos. Se estudia la poesía de Manuel González Prada, en especial a partir de su formación romántica y parnasiana, además de su rol dentro de la caracterización del modernismo hispanoamericano (se buscará problematizar la noción de “modernismo simbolista”). Así mismo, se revisará su “prescriptiva” poética a partir de su Ortometría y de otros textos de versificación y de reflexión lírica. Todo ello, con el objetivo de clarificar en qué medida su obra puede relacionarse con ciertas propuestas del simbolismo, como se trata de evidenciar con la lectura de algunos de los poemas que pertenecen básicamente a su libro Exóticas. Se analiza la obra de José María Eguren, el mayor exponente de una poesía simbolista en nuestro país. El principal objetivo es configurar una lectura intertextual entre su propuesta y la de los textos franceses vinculados a una poética del simbolismo. Además, buscaremos dilucidar los diferentes periodos de su lírica y observar en qué medida se puede establecer una suerte de “evolución” literaria (quitándole, por supuesto, cualquier connotación de jerarquización a dicho término) con el objetivo de tener una visión más profunda e integral de su poética simbolista. Así mismo, se reflexiona sobre su “teoría” estética a partir de sus motivos, muy a sabiendas de que varios de sus escritos oscilan entre el ensayo y el poema en prosa. Finalmente, se realiza una revisión del legado del Simbolismo francés en la poesía peruana de las primeras décadas del siglo XX, previa a la aparición de los “ismos” de Vanguardia o coetánea con los mismos. A partir de ello, serán de mucha utilidad conceptos como neorromanticismo, modernismo y posmodernismo. Pondremos énfasis en escritores que decidieron continuar con su labor literaria en Francia (como el caso meteórico de José Eufemio Lora y Lora), así como poetas que vivieron en Perú, pero que en cierta medida fueron difusores del Simbolismo francés o presentan alguna relación con el mismo, muy a pesar de que el “grueso” de su obra recorrió otros caminos artísticos (en especial autores como José María Barreto, Enrique Bustamante y Ballivián y Alberto Ureta). Tesis

El presente articulo analiza la posible relacion entre la poesia de Jose Maria Eguren y los movimientos vanguardistas de su epoca, en especial el surrealismo y el cubismo. Se revisa los comentarios de poetas vanguardistas sobre la poesia egureniana, asi como su inclusion en una antologia de poesia surrealista latinoamericana. A continuacion, se analiza el poema “Cancion cubista” y se busca demostrar la relacion basicamente ironica entre la poetica egureniana, mas afincada en el simbolismo, y la escuela cubista.

Nitrogen deposition has been shown to have significant impacts on a range of vegetation types resulting in eutrophication and species compositional change. Data from a re-survey of 89 coastal sites in Scotland, UK, c. 34 years after the initial survey were examined to assess the degree of change in species composition that could be accounted for by nitrogen deposition. There was an overall increase in the Ellenberg Indicator Value for nitrogen (EIV-N) of 0.15 between the surveys, with a clear shift to species characteristic of more eutrophic situations. This was most evident for Acid grassland, Fixed dune, Heath, Slack and Tall grass mire communities and despite falls in EIV-N for Improved grass, Strand and Wet grassland. The increase in EIV-N was highly correlated to the cumulative deposition between the surveys, and for sites in south-east Scotland, eutrophication impacts appear severe. Unlike other studies, there appears to have been no decline in species richness associated with nitrogen deposition, though losses of species were observed on sites with the very highest levels of SOx deposition. It appears that dune vegetation (specifically Fixed dune) shows evidence of eutrophication above 4.1 kg N ha(-1) yr(-1), or 5.92 kg N ha(-1) yr(-1) if the lower 95% confidence interval is used. Coastal vegetation appears highly sensitive to nitrogen deposition, and it is suggested that major changes could have occurred prior to the first survey in 1976.

Climate change is expected to have an impact on plant communities as increased temperatures are expected to drive individual species' distributions polewards. The results of a revisitation study after c. 34years of 89 coastal sites in Scotland, UK, were examined to assess the degree of shifts in species composition that could be accounted for by climate change. There was little evidence for either species retreat northwards or for plots to become more dominated by species with a more southern distribution. At a few sites where significant change occurred, the changes were accounted for by the invasion, or in one instance the removal, of woody species. Also, the vegetation types that showed the most sensitivity to change were all early successional types and changes were primarily the result of succession rather than climate-driven changes. Dune vegetation appears resistant to climate change impacts on the vegetation, either as the vegetation is inherently resistant to change, management prevents increased dominance of more southerly species or because of dispersal limitation to geographically isolated sites.

On fuel perspective, Liquefied Petroleum Gas (LPG) provides cleaner emissions and also facilitates lean burn signifying less fuel consumption and emissions. Lean burn technology can attain better efficiencies and lesser combustion temperatures but this temperature is quite sufficient to facilitate formation of nitrogen oxide (NOx). Exhaust Gas Recirculation (EGR) for NOx reduction has been considered allover but extremely little literatures exist on the consequence of EGR on lean burn LPG fuelled spark ignition (SI) engine. The following research is carried out to find the optimal rate of EGR addition to reduce NOx emissions without settling on performance and combustion characteristics. A single cylinder diesel engine is altered to operate as LPG fuelled SI engine at a compression ratio of 10.5:1 and arrangements to provide different ratios of cooled EGR in the intake manifold. Investigations are done to arrive at optimum ratio of the EGR to reduce emissions without compromising on performance. Significant reductions in NOx emissions alongside HC and CO emissions were seen. Higher percentages of EGR further diluted the charge and lead to improper combustion and thus increased hydrocarbon emissions. Cooled EGR reduced the peak in-cylinder temperature which reduced NOx emissions but lead to misfire at lower lean limits.

Physics goals and technical issues related to very high luminosity B Factories are discussed.

El presente artículo es un análisis de las estrategias conceptistas que emplea el clérigo y literato cusqueño Juan de Espinosa Medrano (1639?-1688), mejor conocido como el "Lunarejo", en su defensa de la poesía de Góngora, el Apologético en favor de don Luis de Góngora. Para ello vamos a reflexionar primero sobre la nociónconceptista de "ingenio" y sus estrategias en el contexto barroco, y cómo las mismas influyen en la representación del sujeto criollo durante el proceso de la colonia hispanoamericana con el objetivo de validad su discurso de la subalternidad en el marco de la interacción con la metrópoli española.

La presente tesis es un estudio analítico-interpretativo del poemario Simbólicas (1911) de José María Eguren. Sobre la base de los alcances de la neorretórica y la teoría del símbolo poético, se busca dilucidar la naturaleza y función de los símbolos en el mencionado libro. Para ello se parte de las mismas reflexiones del poeta sobre el símbolo en sus Motivos, así como de la relación entre estas reflexiones y los poemas del libro que nos compete. Además, se problematiza la diferenciación de tres estrategias retórico-figurativas esenciales en el libro: la metáfora, la alegoría y el símbolo. Se busca analizar estas estrategias en correspondencia con el marco teórico formulado, el cual concuerda con la propuesta lírica egureniana en su representación de los símbolos como imágenes que nos hacen comprender y a su vez construir una realidad que, en este caso, es su particular universo poético. Tesis