115 research outputs found
Revista complutense de educación
Resumen basado en el de la publicaciónSe lleva a cabo una revisión general del procedimiento cloze, procedimiento que es ampliamente conocido y utilizado como instrumento de evaluación de la lectura en los países de habla inglesa pero que apenas es conocido y empleado en España. Dicha revisión hace referencia tanto a los aspectos metodológicos relacionados con dicho procedimiento como a los distintos usos para los que puede emplearse en el campo de la evaluación de la lectura.ES
El procedimiento cloze como medida procesal de la comprensión lectora
El procedimiento cloze se utiliza ampliamente hoy en día como una medida del proceso de comprensión lectora en los países de habla inglesa. Sin embargo, hay pocos estudios sobre la validez del procedimiento cloze realizado en idioma español. El presente estudio tiene como objetivo proporcionar algunos datos sobre el uso del procedimiento cloze con sujetos de habla hispana con el fin de contribuir a un mejor conocimiento de esta medida en nuestro país
Factors affecting air pycnometer performance for its use in the composting process
Air filled porosity (AFP) is a crucial factor in composting to guarantee aerobic conditions inside the composting matrix. Among the different methods proposed to measure AFP in composting processes, air pycnometry is defined as the most adequate. There is a lack of a standard methodology for air pycnometry utilization for AFP determination in heterogeneous samples as those from composting materials. Air pycnometers currently used for this purpose are custom made instruments operating under different conditions (sample volume, initial pressure, etc.). All factors affecting air pycnometry accuracy in the composting process are related to the proper maintenance and handling of the air pycnometer and the composting sample. In this study, AFP measurements have been performed in more than 50 samples of a wide range of composting materials using two different custom made pycnometers, one of them coupled to a composting reactor allowing in situ AFP measurement. While temperature variation during AFP measurement has been discarded as an error source, the determination of the sample volume has been found to be a significant factor affecting the air filled porosity calculation. Regarding the initial pressure to use, a compromise between accuracy and practicality has to be established for each pycnometer design as AFP values obtained with diverse initial pressures (from 200 to 500 kPa gauge pressure) were found to present no statistical differences. An initial pressure in the range of 300-500 kPa (gauge pressure) is recommended. In conclusion, there is a need for a standard methodology for AFP determination or prediction at industrial scale. A complete procedure for air filled porosity determination by air pycnometry is also presented in this work
Residus més biodegradables
El tractament de residus sòlids orgànics per obtenir compost -esmena orgànica estable i aplicable al sòl- és un procés d'àmplia aplicació, però complex. Aconseguir que un residu sigui compostat amb èxit, dependrà de que aquest tingui certes característiques químiques i biològiques. Per això, quan aquestes no hi són, existeix la possibilitat de compensar-les mitjançant el cocompostatge. Aquest es basa en l'addició de cosubstrats al residu original, per tal que aquest superi les seves deficiències de partida i pugui ser tractat posteriorment. Seguint aquesta línia, s'han dut a terme una sèrie de proves en el laboratori afegint proteïna, greix i cel·lulosa per separat a fangs de depuradora d'aigües residuals urbanes. Els resultats han estat força positius, tant pel que fa al desenvolupament del procés, com per la conservació del nitrogen en el producte final. Els cosubstrats utilitzats es troben en un nombre important de residus orgànics, especialment aquells que provenen de la indústria agroalimentària. El seu tractament mitjançant compostatge obre una excel·lent via de valorització.El tratamiento de residuos sólidos orgánicos para obtener compuesto - enmienda orgánica estable y aplicable al suelo- es un proceso de amplia aplicación, pero complejo. Conseguir que un residuo sea compostado con éxito, dependerá de que éste tenga ciertas características químicas y biológicas. Por eso, cuando éstas no están, existe la posibilidad de compensarlas mediante el cocompostaje. Éste se basa en la adición de cosustratos en el residuo original, a fin de que éste supere sus deficiencias de partida y pueda ser tratado posteriormente. Siguiendo esta línea, se han llevado a cabo una serie de pruebas en el laboratorio añadiendo proteína, grasa y celulosa por separado a barros de depuradora de aguas residuales urbanas. Los resultados han sido bastante positivos, tanto con respecto al desarrollo del proceso, como por la conservación del nitrógeno en el producto final. Los cosustratos utilizados se encuentran en un número importante de residuos orgánicos, especialmente aquéllos que provienen de la industria agroalimentaria. Su tratamiento mediante compostaje abre una excelente vía de valorización.The treatment of organic solid waste to obtain compost - which can be used as soil conditioner or fertilizer - is a complex process. However, certain physico-chemical and biological characteristics are required in a waste to be successfully composted. When these characteristics are not present, there is the possibility of compensating them through cocomposting. This technique consists in adding a cosubstrate to the original waste to make up for its original deficiencies and facilitate its treatment by composting. Cocomposting was tested with a series of laboratory trials in which protein, fats and cellulose were added to sewage sludge separately. The results were quite positive not only due to enhancement of the composting process evolution but also for the increase in nitrogen conservation in the final product. The cosubstrates used can be found in different organic wastes specially those from the food industry. The treatment of these wastes though composting offers an excellent opportunity for their valorization
Biodegradation of animal fats in a co-composting process with wastewater sludge
A composting process was proposed as an effective technology for the biodegradation of fats in a proportion of 40-50%. Anaerobically digested sludge was used as co-substrate for animal fats to balance the C/N ratio of the composting mixture and to provide additional biodegradable organic matter and active biomass. Two different strategies were studied: static pile and dynamic turned pile. Air-filled porosity was initially adjusted to 40% for both experiments. It was observed that non-turned strategy increases the formation of material agglomerates which derived in a non-homogeneous fat distribution, the development of filamentous fungi, and a considerable increase in the amount of leachate generated. Turning the composting material resulted in the best results for composting fat-enriched wastes, preventing the formation of agglomerates. An effective biodegradation up to 92% of the fats was observed under these conditions. Besides, the addition of fats increased significantly the duration of the thermophilic period of the composting process
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