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A Simple Detection System for Two Classical Sagnac Interferometer Configurations

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Engineering（科研） 2012年第12期4卷 903-907页

作者： Gabriel eduardo Sandoval-Romero Enrique Francisco Pinzón-escobar Centro de Ciencias Aplicadas y Desarrollo Tecnológico Universidad Nacional Autónoma de México México

Two interferometric systems were built, one in bulk optics and other one in fiber optics for showing the instrumentation stage designed for these devices, supported in a photodetector. This stage has a circuit for amplification, analog filtering and software for single channel data acquisition and digital filtering. Based on the Sagnac effect in bulk optics and in fiber optics, the Sagnac interferometer has many applications, nevertheless the methods of construction, design and instrumentation for the sensors used on both types of interferometers are well-known, but very common or general form, for this reason this work approaches some of the methodologies for the design and construction of these devices, obtaining higher sensitivity and better contribution in its respective interferometric paths. We used the simplest design for each interferometer, proposing the best detection limit for each one;to obtain the previous thing, we implement the three previous steps: amplifiers and analogous filters, software for filtering the digital sign. The data acquisition method used to allow us to obtain faster results, using the card of a PC, getting real time measurements and digital processing of the signal.

关键词： Sagnac Interferometer Instrumentation Photodetector Data Acquisition

Changes in the Composition and Abundance of Phytoplankton in a Coastal Lagoon of Baja California,Mexico,during 2011

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Open Journal of Marine Science 2015年第2期5卷 169-181页

作者： María Fernanda Gracia-escobar Roberto Millán-Núnez Enrique Valenzuela-Espinoza Adriana González-Silvera eduardo Santamaría-del-Angel Facultad de Ciencias Marinas Universidad Autónoma de Baja CaliforniaEnsenadaMéxico Instituto de Investigaciones Oceanológicas Universidad Autónoma de Baja CaliforniaEnsenadaMéxico

A time series with weekly sampling was conducted from February 20, to December 16, 2011 at a station in the interior of the San Quintín Bay to estimate seasonal changes in the composition and abundance of phytoplankton. Water temperature was recorded and the upwelling index was calculated for the period. Phytoplankton abundance was estimated and phytoplankton were identified by using an inverted microscope and the CHEMTAX program. There were 16 positive phytoplankton anomalies during the year, but only three were considered to be blooms. The blooms were dominated by diatoms and were recorded in the winter, spring and summer. Different genera composed 80% of the total phytoplankton abundance of each of the blooms. The first bloom consisted of diatoms of the genera Pseudo-nitzschia sp. (15.7%), Skeletonema sp. (14.6%), Eucampia sp. (7%), and Navicula sp. (7%);a haptophyte of the genus Imantonia sp. (13.1%);and dinoflagellates of the genus Prorocentrum sp. (4.6%). The second bloom consisted mainly of diatoms of the genera Guinardia sp. (30.6%), Pseudo-nitzschia sp. (21.5%), Skeletonema sp. (14.5%), Chaetoceros sp. (8.4%) and Eucampia sp. (5.3%). The third bloom consisted of Chaetoceros sp. (46.3%), Pseudo-nitzschia sp. (22.6%), Skeletonema sp. (7.29%), and Imantonia sp. (6%). Dinoflagellates were observed in the winter, summer and autumn, but they contributed less biomass than diatoms. Prorocentrum sp., Gymnodinium sp., and Ceratium sp. were among the dinoflagellates that were observed. The differences in abundance and composition of phytoplankton groups in the blooms in San Quintín Bay during 2011 were due primarily to seasonal changes in the physical and chemical factors of the seawater and to upwelling events.

关键词： Phytoplankton Bloom Pigments CHEMTAX Coastal Lagoon

Changes in the Abundance and Composition of Phytoplankton in a Coastal Lagoon during Neap-Spring Tide Conditions

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Open Journal of Marine Science 2014年第2期4卷 80-100页

作者： María Fernanda Gracia-escobar Roberto Millán-Núnez Adriana González-Silvera eduardo Santamaría-del-Angel Víctor F.Camacho-Ibar Charles C.Trees Facultad de Ciencias Marinas Universidad Autónoma de Baja CaliforniaEnsenadaMéxico Instituto de Investigaciones Oceanológicas Universidad Autónoma de Baja CaliforniaEnsenadaMéxico NATO Undersea Research Centre La SpeziaItaly

The objective of this work was to estimate the changes in abundance and composition of phytoplankton in a coastal lagoon in Baja California, México during neap-spring tide conditions. Sampling was conducted from the 7th to the 16th of October 2004. Surface water was collected at 18 stations distributed across the bay during day time at high tide. Also, a time series was collected at a fixed station;surface water was collected every two hours from 8:00 to 18:00. High temperatures, low salinities and low nutrient concentrations at the oceanic end indicated weak or non upwelling conditions during this period. The phytoplankton community was characterized using an inverted microscope and the chemical taxonomy program CHEMTAX, based on pigment concentration estimated by high performance liquid chromatography (HPLC). The phytoplankton concentration was two times lower during this period than during periods of upwelling in the same year. Cryptophytes and diatoms were the most abundant groups estimated by CHEMTAX. Statistical analyses of the effect of tidal conditions on phytoplankton composition indicate that Zone A is strongly affected by tides, and that tidal effects are lessened at the inner zones. Differences in phytoplankton abundance between zones and between tidal conditions indicate that phytoplankton distribution is patchy in the lagoon.

关键词： Phytoplankton HPLC Pigments CHEMTAX Tides Coastal Lagoon

Exhaust Ventilation through a Solar Chimney： A Response to High Hermeticity in Welfare Housing

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Journal of Civil Engineering and Architecture 2015年第7期9卷 767-774页

作者： Marcos eduardo Gonzalez-Trevizo Adolfo Gomez-Amador Anibal Luna-Leon Carlos escobar-Del POZO Carlos Javier Esparza Lopez Facultad de Arquitectura (Faculty of Architecture) Universidad Michoacana de San Nicoldls de Hidalgo (Michoacan Universityof Saint Nicholas of Hidalgo) Morelia MN 58030 Mexico Facultad de Arquitectura y DiseFzo (Faculty of Architecture and Design) Universidad de Colima (University of Colima) ColimaCL 28400 Mexico Facultad de Arquitectura y Diseho (Faculty of Architecture and Design) Universidad Aut6noma de Baja California (BajaCalifornia Autonomous University) Mexieali BC 21280 Mexico Facultad de Ingenieria Mecnica y Elctrica (Faculty of Mechanical and Electrical Engineering) Universidad de ColimaColima CL 28400 Mexico

This research reports on potentiality in the solar chimney as an exhaust ventilation device through a hypothetical statement that convenient weather conditions exist on sub-humid warm climate to enhance the performance of a SC (solar chimney), in order to increase ventilation to dissipate metabolic heat from inhabitants of airtight buildings. The methodology used in this research integrates the use of simplified mathematical models that predict in a semi-empirical way a potential volume flow through estimation of kinetic power generation, by natural circulation and stack effect in a typical covered-plate air solar collector. The study was carried out during the warm month of April, an important warm season for Colima, where the prevailing wind is about 6.8 m/s, the average temperature of maximums and minimums oscillates between 15.4 °C and 34.4 °C with average relative humidity of 65% according to national weather service. A scale model of the SC was installed on environmental chambers. The results showed that this device is capable of generating ventilation conditions around light breeze parameters near between 0.6 m/s and 1.5 m/s width, a better performance at day in 45% approximately than the night values, making ventilation rates up 0.24 ACH (air changes per hour) as average air change rate.

关键词：太阳能烟囱高密封性通风排气空气集热器福利平均温度通风装置数学模型