Analysis of double-parallel amplified recirculating optical-delay lines

A novel method of analysis of double-parallel amplified recirculating optical-delay lines (DPAROD) is presented. The location of the maxima and the minima of the transfer function for this configuration is calculated and experimentally demonstrated. The influence of different parameters, such as the coupling coefficients, gains, lengths of the fiber loops and fractional losses of the directional couplers, on the shape of the transfer function are analyzed. Different measurements have been taken to verify this model. The potential application of these interconnected delay loops as filters is a reason for developing this method.Publicad

Amplified Fiber-Optic Recirculating Delay Lines

Experimental and theoretical results on single- and double-amplified recirculating delay lines are presented. One of our aims is to emphasize their application as filters, showing a wide flexibility of design. Analysis of their performance in the spectral and time domains have been carried out. A novel method of understanding the behavior of double structures has been developed and successfully tested with experimental results employing Er-doped fiber amplifiers as delay lines.Publicad

Recent sediments of the Eume river: mineralogical and textural composition

[Resumen] Se analiza la granulometría, textura y mineralogía de sedimentos recogidos en los fondos de la ría de Ares, estuario y tramo final del río Eume. Texturalmente, las muestras se agrupan en francolimosas o francoarenosas y su distribución está defmida según las características dinámicas de la ría y las modificaciones realizadas por las obras de infraestructura. La mineralogía de la fracción arcilla es muy homogénea, con caolinita y filosilicatos 2: 1 dominantes, junto con pequeñas antidades de cuarzo y feldespato. El contenido en carbonatos es bajo, siempre menor del 30 %, destacando los porcentajes encontrados en el sondeo de la cola del embalse del Eume, de origen claramente antrópico. Textura y mineralogía son coherentes con el marco geológico del que proceden, excepto en la presencia de carbonatos y exceso de partículas finas con caolinita cristalina existentes en la cola del embalse del Eume. La distribución de las partículas, según su tamaño, obedece fundamentalmente a causas naturales, pero existen imponantes modificaciones relacionadas con el papel de barrera del embalse y las obras de infraestructura que han alterado la circulaci6n original en algunas zonas del estuario y desembocadura.[Abstract] A textural and mineralogical analysis is made to sediments sampled at the bottom of the Ría de Ares, estuarine and Eume river. Clay mineralogy is very similar for all the samples and consists of kaolinite and 2: 1 phyllosilicates with small amounts of quartz and fe'ldspar. The percentage of carbonates is small, always less than 30 o/o. There should be pointed out the values found in the Eume reservoir core, with a clear antropic origino Texture and mineralogy are coherent with the geology of the basin they come from, excepting the carbonates and fine particle excess with cristaline caolinite in the Eume reservoir core. Size grain distribution is due to the dinamic characteristics of the ría, but there are important rnodifications related to the reservoir, that acts as a barrier, and the constructions in the lower part of the river that have changed the original circulation in sorne areas of the ría

Meteorización de las granulitas de Cabo Ortegal

[Resumen] Se realiza el estudio químico y mineralógico del proceso de alteración, en medios sustractivos, de las granuli tas de Cabo Ortegal, la precipi tación media anual supera los 1.300 mm. y las temperaturas medias mensuales extremas son 23ºC y 4,7ºC. Durante el proceso de meteorizaciór se origina una fuerte pérdida de Ca, Na y Mg y,en menor proporción, de Si con acumulación relativa de Fe y Al. Como productos de alteración aparecen filosilicatos 1:1 dioctaédricos, gibbsita, oxihidróxidos de hierro y micas y cloritas degradadas. La edafogénesis es de tipo fermonosialítico con una tendencia ferralítica, al menos en sus fases iniciales.[Abstract] This paper is a chemical and mineralogical study about the weathering process, in subtr&ctive environments, of the granul i tes in Cabo Ortegal. The mean annual precipitation is over 1.300 mm. and the mean monthly extreme temperatures are 23ºC and 4,7ºC . In the process of weathering there is an intense 10S8 of Ca, Na and Mg and, in a minar level , of Si, with a relative accumulation of Fe and Al. Proqucts of the weathering are 1: 1 dioctahedral phyllosilicates, gibbsi teiron oxyhydroxides and degraded micas and chlorites. The pedogenesis is of fermonosialli tic type wi th a ferrallitic tendence, in the first phases at least