El presente trabajo consiste en una investigación de tipo documental, enfocada en el desarrollo histórico de los refrigerantes, haciendo énfasis en los freones comerciales elaborados a base de ...cloro-flúor-carbonos (CFC), los cuales generaron el primer cuestionamiento como agotadores de la capa de ozono, fundamentado en el valioso aporte a la humanidad de Mario Molina y Sherwood Rowland, galardonados en 1995 con el Premio Nobel de Química, al demostrar al mundo los daños ocasionados en la capa de ozono y ser precursores en la solución, iniciada a partir del protocolo de Montreal. Adicionalmente, se expone el destino de los refrigerantes según estudios actuales. Gracias al trabajo realizado por Molina y Rowland al conjugar la relación entre la ciencia, la industria y la actividad diplomática, se alcanza a ver resultados que se traducen en beneficios transcendentales al planeta. El uso de la refrigeración continuará, pero deben seguir las investigaciones que aumenten el conocimiento en técnicas que no deterioren el ambiente, considerando así el ozono para la vida, para la preservación y vida futura.
A rádio ocultação (RO) começou a ser utilizada para a sondagem da atmosfera de outros planetas a partir da década de 1960. Com o desenvolvimento do Global Navigation Satellite System (GNSS) e de ...missões com satélites de baixa órbita (Low Earth Orbit - LEO) surgiu a possibilidade de investigações da atmosfera terrestre com a aplicação da RO-GNSS. Dos satélites transmissores GNSS até os receptores instalados nos satélites LEO, os sinais propagados sofrem diferentes tipos de influência da atmosfera. O sinal transmitido é refratado e, com isso, pode ser coletado pelo receptor embarcado no LEO, apesar da obstrução pela Terra. Essa geometria possibilita o cálculo dos índices de refração, os quais possuem informações da composição da atmosfera terrestre. Entre os perfis obtidos a partir do índice de refração, destacam-se os de temperatura, pressão e densidade de elétrons. No presente trabalho é realizada uma revisão teórica da técnica de RO-GNSS, com o intuito de apresentar a técnica e seu potencial a pesquisadores de diversas áreas que tenham possibilidade de utilizá-la. Primeiramente é apresentado um breve histórico do desenvolvimento da técnica, bem como as principais missões relacionadas ao tema, incluindo a situação de missões atualmente em operação e algumas perspectivas futuras. Além disso, são apresentados os principais elementos envolvidos na geometria da ocultação, bem como os principais conceitos e formulações para a obtenção dos perfis. Por fim, alguns produtos provenientes de missões de RO-GNSS são apresentados e analisados.
The study of meteorology are based on atmospheric phenomena, your behavior and physical, chemical and dynamic interactions with the other elements of the Earth's surface. The aim of this study was to ...characterize climatically the municipality of Feira de Santana (BA), as to the availability of water for farming, using data provided by INMET, which were processed through the climatic water balance method, from which he obtained the water index, index of dryness and moisture content, and aid the sort keys of Thornthwaite. The water balance showed that the municipality features an ETP of 1431.7 mm year-1, ETR to 720.7 mm year-1, DEF of 711.0 mm year-1 and EXC equal to zero. The climatic type through the methodology of Köppen's "wing", megatérmico with winter rains and hot summers, whereas Thornthwaite's C1w2A ' a ', Sub-humid climate with dry off excess summer, megatérmico and potential evapotranspiration in summer concentration equal to 31.2%. The municipality of Feira de Santana presents a high ETP, influenced by high temperatures. The period of lowest water deficiency is recorded in the months of may, June and July, being suitable for dryland crops. The Thornthwaite climate classification method offers greater detail than the Köppen.
Neste trabalho, foi desenvolvida uma estação meteorológica automática e de baixo custo utilizando materiais reaproveitados e sensores de baixo custo, conectada ao site de visualização e gerenciamento ...de dados Ubidots. A estação conta com sensores de temperatura (AHT10), umidade (AHT10), pressão (BMP180), radiação solar (LDR), um pluviômetro e um anemômetro digital, ambos feitos com materiais reaproveitados e de fácil acesso, tendo sido o anemômetro desenvolvido com uma ventoinha (sensor hall) e o pluviômetro baseado num sensor magnético reed switch. Todo o sistema é conectado à placa de prototipagem eletrônica ESP8266, a qual já possui um módulo que permite a conexão com a internet. Todo o dispositivo foi custeado com cerca de 50 reais. Os sensores de temperatura, umidade e o anemômetro foram calibrados utilizando sensores padrão para garantir uma medição precisa. Os valores de umidade e temperatura foram então comparados aos dados obtidos por uma estação profissional próxima. O pluviômetro também passou por uma calibração para medir a quantidade de chuva em milímetros. Além disso, foram implementadas previsões baseadas em modelos para estimar o ponto de orvalho, pressão de vapor d’água, água precipitável e sensação térmica, fornecendo informações adicionais sobre as condições do tempo local.
In this work, a low-cost automatic weather station was developed using reused materials and low-cost sensors, connected to the Ubidots data visualization and management website. The station has sensors for temperature (AHT10), humidity (AHT10), pressure (BMP180), solar radiation (LDR), a rain gauge and a digital anemometer, both made with reused and easily accessible materials, the anemometer being developed with a fan (hall sensor) and the rain gauge based on a reed switch magnetic sensor. The entire system is connected to the ESP8266 electronic prototyping board, which already has a module that allows connection to the internet. The entire device cost around 50 R$. The temperature and humidity sensors and anemometer were calibrated using standard sensors to ensure accurate measurement. Humidity and temperature values were then compared to data obtained from a nearby standard weather station. The rain gauge also underwent calibration to measure the amount of rain in millimeters. Additionally, model-based forecasts were implemented to estimate dew point, water vapor pressure, precipitable water, and wind chill, providing additional information about local weather conditions.
Pós-colheita de Annona squamosa L. recobertas com filme PVC Reges, Bianca Mara; Batista, Elisabeth Mariano; Almeida, Érica Jamily do Nascimento ...
Revista verde de agroecologia e desenvolvimento sustentável,
10/2018, Letnik:
13, Številka:
4
Journal Article
Recenzirano
Odprti dostop
Objetivou-se com o presente trabalho avaliar a qualidade pós-colheita de ata submetida ao atraso na retirada do filme de PVC. Os frutos foram colhidos no estádio de maturidade fisiológica; em ...seguida, selecionados e sanitizados. Parte deles foi envolvida individualmente com filme de PVC comercial e acomodada em bandeja de isopor e os demais foram mantidos sem filme, representando o controle. Os tratamentos aplicados foram: (Controle) sem filme de PVC, (T1) embalados individualmente com filme de PVC sendo retirados com 2 dias de armazenamento, (T2) Filme de PVC sendo retirado com 4 dias de armazenamento e (T3) Filme de PVC sendo retirado com 6 dias de armazenamento. As análises físicas e físico-químicas foram realizadas a cada 2 dias de armazenamento. As características analisadas foram perda de massa fresca (%), firmeza da polpa (N), aparência externa, índice de rachadura, acidez titulável (mg.100L-1), pH, sólidos solúveis (ºBrix) e ratio (SS/AT). A utilização de filme de PVC retardou a perda de massa das atas e diminuiu os teores de acidez titulável, além de ter contribuído para melhor aparência externa. Os tratamentos T2 e T3 mantiveram a firmeza mais elevada até o 6º dia, quando comparados aos demais tratamentos. O aparecimento de rachaduras foi menor no controle. O filme de PVC atrasou o amadurecimento dos frutos, mas não diminuiu a qualidade das atas ao final do armazenamento. O filme de PVC retirado com 6 dias proporcionou uma vida útil pós-colheita de 6 dias, pois apesar de conter rachaduras, estava apto para o consumo.
•We study the dynamics of a cyclone coupled with two anticyclones in Saturn.•They locate in a singular double-peak eastward jet and have survived for 4 years.•In 2015, a disturbance took place at the ...location of the three-vortex system.•We find that features pertaining to the disturbance moved with jet speeds.•Numerical models reproduce the stability of the three-vortex system.
The zonal wind profile of Saturn has a unique structure at 60°N with a double-peaked jet that reaches maximum zonal velocities close to 100 ms−1. In this region, a singular group of vortices consisting of a cyclone surrounded by two anticyclones was active since 2012 until the time of this report. Our observation demonstrates that vortices in Saturn can be long-lived. The three-vortex system drifts at u = 69.0 ± 1.6 ms−1, similar to the speed of the local wind. Local motions reveal that the relative vorticity of the vortices comprising the system is ∼2–3 times the ambient zonal vorticity. In May 2015, a disturbance developed at the location of the triple vortex system, and expanded eastwards covering in two months a third of the latitudinal circle, but leaving the vortices essentially unchanged. At the time of the onset of the disturbance, a fourth vortex was present at 55°N, south of the three vortices and the evolution of the disturbance proved to be linked to the motion of this vortex. Measurements of local motions of the disturbed region show that cloud features moved essentially at the local wind speeds, suggesting that the disturbance consisted of passively advecting clouds generated by the interaction of the triple vortex system with the fourth vortex to the south. Nonlinear simulations are able to reproduce the stability and longevity of the triple vortex system under low vertical wind shear and high static stability in the upper troposphere of Saturn.
The infrasound field, the science of low-frequency acoustic waves, has developed into a broad interdisciplinary field encompassing academic disciplines of physics and recent technical and scientific ...developments. In 1996, the United Nations General Assembly adopted the Comprehensive Nuclear-Test-Ban Treaty (CTBT), prohibiting atmospheric nuclear explosions worldwide. The infrasound network of the International Monitoring Network (IMS) of the CTBT-Organization has demonstrated its capability for detecting and locating infrasonic sources such as meteorites, volcanic eruptions, earthquakes, auroras, mountain associated waves... Nearly 70% of the global network is now operational and regional cluster arrays are deployed around the globe. Systematic investigations into low-frequency acoustic signals have evidenced an unprecedented potential of the monitoring of infrasonic waves permanently generated by natural and man-made events. Furthermore, recent studies point out new insights on quantitative relationships between observables and atmospheric specifications, and therefore opening new fields into the mathematics of geophysical inverse problems for atmospheric remote sensing. This volume reviews the most important areas of infrasound, with emphasis on the latest researches and applications, e.g. instrumentation, engineering, signal processing, source monitoring, propagation modeling, atmospheric dynamics, global changes, remote sensing methods. Researchers and students will benefit from a comprehensive content of infrasound related topics, where both fundamental and applied topics are discussed by authors from international institutions, all experts in their fields.
Climate dynamics Sun, De-Zheng; Bryan, Frank
♭2010., Letnik:
189
eBook
Recenzirano
Published by the American Geophysical Union as part of the Geophysical Monograph Series, Volume 189. Climate Dynamics: Why Does Climate Vary? presents the major climate phenomena within the climate ...system to underscore the potency of dynamics in giving rise to climate change and variability. These phenomena include deep convection over the Indo-Pacific warm pool and its planetary-scale organization: the Madden-Julian Oscillation, the monsoons, the El Niño-Southern Oscillation, the Pacific Decadal Oscillation, and the low-frequency variability of extratropical circulations. The volume also has a chapter focusing on the discussion of the causes of the recent melting of Arctic sea ice and a chapter devoted to the discussion of the causes of recent changes in the frequency and intensity of tropical cyclones. On each topic, the basic material of climate dynamics is covered to aid the understanding of the forefront research, making the volume accessible to a broad spectrum of readers. The volume highlights include Diabatic and nonlinear aspects of the El Niño-Southern Oscillation Causes of sea ice melting in the Arctic Impact of global warming on tropical cyclone activity Origins of the Pacific Decadal Oscillation Causes of climate variability of Asian monsoons The volume will be of particular interest to graduate students and young researchers in atmospheric and oceanic sciences and related disciplines such as geology and geography. The book will also be a good read for those who have a more general interest in the Earth's climate and why it varies.
W niniejszej pracy zaprezentowano eksperyment bezpośrednich testów zapalności wyładowań elektrostatycznych snopiastych. Badania zostały przeprowadzone z wykorzystaniem sondy zapłonowej opisanej w ...normie PN-EN 60079-32-2 wzbogaconej o układ pomiaru prądu wyładowania. Przeprowadzono 100 prób zapłonu mieszaniny wybuchowej. Zaobserwowano wpływ przebiegu prądu wyładowania na zdolność wyładowania do spowodowania inicjacji zapłonu. Wyniki eksperymentu zestawione na wykresie wykazują pewną regularność, która została opisana „krzywą wybuchowości”
We present the High-Elective Resolution Modelling Emission System version 3
(HERMESv3), an open source, parallel and stand-alone multi-scale atmospheric
emission modelling framework that computes ...gaseous and aerosol emissions for
use in atmospheric chemistry models. HERMESv3 is coded in Python and consists
of a global_regional module and a bottom_up module
that can be either combined or executed separately. In this contribution
(Part 1) we describe the global_regional module, a customizable
emission processing system that calculates emissions from different sources,
regions and pollutants on a user-specified global or regional grid. The user
can flexibly define combinations of existing up-to-date global and regional
emission inventories and apply country-specific scaling factors and masks.
Each emission inventory is individually processed using user-defined
vertical, temporal and speciation profiles that allow obtaining emission
outputs compatible with multiple chemical mechanisms (e.g. Carbon-Bond 05).
The selection and combination of emission inventories and databases is done
through detailed configuration files providing the user with a widely
applicable framework for designing, choosing and adjusting the emission
modelling experiment without modifying the HERMESv3 source code. The
generated emission fields have been successfully tested in different
atmospheric chemistry models (i.e. CMAQ, WRF-Chem and NMMB-MONARCH) at
multiple spatial and temporal resolutions. In a companion article (Part 2;
Guevara et al., 2019) we describe the
bottom_up module, which estimates emissions at the source level
(e.g. road link) combining state-of-the-art bottom–up methods with local
activity and emission factors.
PDF
