Resumen En este trabajo se evalúa la eficiencia en la extracción del glucósido cianogénico amigdalina de semillas de manzanas (Maluspumila Mill) empleando las técnicas tradicionales con solventes de reflujo y Soxleth, las cuales son comparadas con la técnica más contemporánea de microondas. Las eficiencias de extracción son determinadas a través de cromatografía líquida de alta eficiencia (HPLC) empleando un método estandarizado que requiere tiempos de retención de alrededor de 1 minuto. La mejor separación cromatográfica es obtenida con el método de reflujo; sin embargo, la eficiencia de separación total más alta es alcanzada empleando la técnica de microondas, la cual requiere de solo un 10% del tiempo total y solventes necesarios en las extracciones por reflujo y Soxhlet. En contraste, la mayor cantidad de extraída de amigdalina de las semillas es obtenida con la técnica de Soxhlet, la cual corresponde al triple y al doble de las cantidades que logran ser extraídas con las metodologías de reflujo y microondas respectivamente. La pureza e identificación estructural de la amigdalina extraída es verificada espectroscópicamente usando las técnicas de UV-vis, RMN (*H and 13C) y FTIR.

Abstract This work evaluates the efficiency in the extraction of the cyanogenic glycoside amygdalin [D-mandelonitrile- p-D-gentiobioside] from seeds of apples (Malus pumila Mill) by using the two most conventional solid-to-liquid methodologies (reflux and Soxhlet) in relation to the more contemporary microwave technique. The extraction efficiencies are determined by an optimized and standardized high-performance liquid chromatography (HPLC) method that requires retention times of about 1 min only. The best chromatographic separation of amygdalin is found in extracts obtained using the reflux method; however, the highest total separation efficiency, requiring only 10% of total time and the solvents inverted in reflux or Soxhlet extraction, is reached by employing microwave radiation. In contrast, the higher extraction amounts of amygdalin from the seeds are obtained using the Soxhlet solid-to-liquid technique. With the Soxhlet methodology, quantities of amygdalin from apple seeds are obtained in excess of three times and twice those obtained with reflux and microwave methodologies, respectively. The purity and structural identification of the extracted amygdalin were verified spectroscopically using UV-vis, NMR and FTIR techniques.

La fotocatálisis con UV/TiO2 usando películas delgadas fue empleada para el tratamiento de agua residual de microbiología. Se empleó un método simple de sedimentación por gravedad sobre sustrato de vidrio para la preparación de las películas. El uso de Na4P2O7, microondas y ultrasonido fue estudiado para la disminución de los granos de TiO2 en las películas. Se estableció que el mejor método para disminuir los agregados resultó de una combinación de Na4P2O7 (0.01M) y radiación de microondas (700 W, 20 min). Las películas fueron caracterizadas por métodos microscópicos y espectroscópicos. Se obtuvo la fase anatasa (brecha de energía de 3.2 e.V) y tamaños de grano de 83nm. Los ensayos fotocatalíticos utilizando las películas de TiO2generaron un 99.5% de decoloración, 79% de remoción de COT y una inactivación microbiana total luego de 14 h de tratamiento. No se encontró reactivación microbiana luego de 48 h de finalizado el tratamiento

Microbiology cell-staining wastewater was treated by UV/TiO2 thin films photocatalysis. A simple method of applying gravity sedimentation over glass-type substrate was used for the preparation of the films. The use of Na4P2O7, microwaves, and ultrasounds were studied for decreasing the TiO2 grain sizes on the films. It was established that the best method for reducing grain size resulted from a combination of Na4P2O7 (0.01M) and microwave radiation (700 W, 20 min). The Films were characterized by several microscopic and spectroscopic methods. Anatase phase (gap energy of 3.2 eV) and grain sizes averaging 83 nm were achieved. Photocatalysis tests using TiO2-films showed 99.5 % of decolorization, 79 % TOC abatement, and total microbial inactivation after 14 h of treatment. No bacteria re-growth was found 48 h after the treatment was completed

A dinâmica de operação dos filtros de areia afeta o desempenho hidráulico do sistema de irrigação, elevando a perda de carga e alterando a altura manométrica total do sistema. Buscando entender parte dessa dinâmica, o objetivo deste trabalho foi determinar o efeito da estrutura interna de filtros de areia na perda de carga de três modelos de equipamentos fabricados no Brasil, sem a presença do elemento filtrante e utilizando água limpa. Adicionalmente, com o ajuste do modelo matemático exponencial aos dados experimentais, procurou-se estabelecer comparações entre os tipos de estrutura dos filtros avaliados. Os ensaios foram realizados em um módulo experimental construído no Laboratório de Hidráulica e Irrigação da FEAGRI/UNICAMP. Os resultados mostraram que a estrutura hidráulica interna dos filtros determinou comportamentos hidráulicos diferenciados e que os tipos de estruturas (placa difusora e drenos) alteraram o padrão de operação dos modelos ensaiados. A função matemática proposta representou, significativamente, o fenômeno físico de perda de carga para as condições do experimento.

The dynamic of operation of sand filters affect the hydraulic performance of irrigation systems, increasing the head loss and changing the total dynamic head of the system. Trying to understand part of this dynamic, the objective of this research was to determine the effect of internal hydraulic structures in the head loss of three sand filters of commercial models, manufactured in Brazil and operating without the filter layer and with clean water. In addition, using an exponential mathematical model adjusted to the experimental data, comparisons among types of structure of each evaluated filter were performed. The trails were accomplished in the experimental module developed in the Laboratory of Hydraulics and Irrigation of FEAGRI / UNICAMP. The results showed that the filters structures determined differentiate hydraulic behaviors and each type of structures (diffuser plate and drains) change the standard operation for the evaluated filters. The mathematical function proposed represented significantly the head loss physical phenomenon for the experimental conditions.

O processo da retrolavagem consiste na passagem da água através do filtro em sentido contrário ao fluxo de filtragem com o objetivo de remover partículas orgânicas e inorgânicas retidas no meio filtrante. O projeto de filtros de areia com configurações ineficientes e a ocorrência de condições operacionais inadequadas contribuem para limitar o desempenho desse processo, causando deficiências na limpeza dos meios filtrantes e comprometendo o funcionamento dos sistemas de irrigação localizada. O objetivo do presente trabalho é proporcionar uma revisão sobre os conceitos associados ao processo da retrolavagem nos filtros de areia, relacionando informações existentes na literatura com experiências de laboratório. Foi gerado um texto básico com informações técnico-científicas sobre o tema, visando a criar um momento de reflexão sobre o processo de retrolavagem e a contribuir para a melhoria do desempenho desses equipamentos na irrigação localizada.

The backwash process consists of water passing through the filter in the opposite direction of the filtering flow to remove organic and inorganic particles of media filter. Inefficient sand filters designs and the occurrence of inadequate operating conditions contribute to restrict the process performance, causing deficiencies in the filter cleaning and compromise the operation of localized irrigation systems. The objective of this study is to provide a review about concepts associated with the backwash process in sand filters, relating literature information with laboratory experiments. A basic documentation was produced with technical and scientific information on this subject to create a reflection about the backwash process and contribute to the improvement of the equipment performance in the localized irrigation.