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Анализ деполимеризации изоляционных составов обмоток электродвигателей на основе ультразвукового излучения
No full textThis work is a continuation of the fundamental study on implementing an innovative method of repairing electric motors using ultrasound. A study of the method of dismantling windings based on ultrasound has been carried out for the purpose of energy efficiency, environmental friendliness and less time spent on the repair cycle of electric motors in terms of removing the stator winding. The investigated dismantling method is optimal for a number of technical issues in comparison with the existing methods for dismantling electric motor windings. In the work, the main focus is on the material of the winding insulation. Lacquer and compound types of insulation of industrial electric motors, which are the main ones everywhere, have been analyzed. The analysis of the impregnating electrical insulating compositions of the stator windings of electric motors and the influence of ultrasound on them during dismantling of the windings of electric motors at different levels of influence of forcing factors: duration and power of ultrasonic action, concentration and temperature of the working solution. The applied mathematical software systems for calculation and modeling guarantee the reliability and rationality of the results of the experiments obtained during the work. A system of equations has been modeled and models of the effect of useful factors relative to each other have been constructed, the results obtained have been optimized and the optimal parameters of both varnish and compound insulation systems have been identified. The optimal parameters of the investigated types of insulation show encouraging results on many important points: duration, energy consumption, environmental friendliness.Данная статья является продолжением фундаментального изучения инновационного метода ремонта электродвигателей с помощью воздействия ультразвука. Проведено исследование метода демонтажа обмоток на основе ультразвука в целях энергоэффективности, экологичности и меньших временных затрат на цикл ремонта электродвигателей в части выемки обмотки статора. Исследуемый способ демонтажа оптимален по ряду технических вопросов в сравнении с существующими методами демонтажа обмоток электродвигателей. В работе основной упор сосредоточен на материале изоляции обмоток. Анализируется лаковая и компаундная виды изоляции промышленных электродвигателей, которые повсеместно являются основными. Произведен анализ пропиточных электроизоляционных составов обмоток статора электродвигателей и влияние ультразвука на них при демонтаже обмоток электродвигателей при разных уровнях влияния воздействующих факторов: продолжительности и мощности ультразвукового воздействия, концентрации и температуры рабочего раствора. Применяемые математические программные комплексы по вычислению и моделированию гарантируют достоверность и рациональность полученных в ходе работы результатов проведенных экспериментов. Смоделирована система уравнений и построены модели воздействия полезных факторов относительно друг друга, произведена оптимизация полученных результатов и выявлены оптимальные параметры как лаковой, так и компаундной систем изоляции. Оптимальные параметры исследуемых типов изоляции показали обнадеживающие результаты по многим важным пунктам: продолжительности, энергозатрат, экологичности.PublishedReferee
Fishing eels
No full textAn unidentified man on a Winter day with more than ten eels over snow. The photo was taken at an unidentified location in the North West of England. This photo is part of a Photo Album that includes pictures from 1935 to 1954.Environment Agency Archives North WestImage taken from Historic Photo Collection containing images on Fisheries and Fish pass construction from 1935 to 1954. The album, originally owned by the Environment Agency North West, is now held by the Freshwater Biological Association
Ecological shallow water delimitation of the Serrana, Roncador, and Quitasueño Atolls of the Seaflower Biosphere Reserve in the Colombian Caribbean
No full textPara contribuir al conocimiento de los fondos coralinos de la Reserva de Biosfera Seaflower (RB Seaflower), se realizó la actualización cartográfica a escala 1:50 000 de unidades ecológicas del paisaje (UEP) para los atolones de Serrana, Roncador y Quitasueño, basada en el procesamiento e interpretación de imágenes del sensor satelital ALOS AVNIR–2 en 2012. Para la asignación temática se utilizó como referencia productos cartográficos previos, información de campo y descripciones ecológicas de la comunidad bentónica. En total se delimitaron 138 967 ha y 30 UEP, de las cuales 32 908 ha corresponden a Serrana, 4 861 a Roncador y 101 198 a Quitasueño. Los productos generados representan una buena aproximación de la disposición, extensión y distribución de los elementos del paisaje bentónico, constituyéndose en información de línea base crucial para el manejo de estos atolones. Además, hacen parte del Mapa de Ecosistemas Continentales Costeros y Marinos de Colombia a escala 1:100 000 (MEC100K) y del Atlas de Áreas Coralinas de Colombia (AACC) actualizado en plataforma digital a 2020. Sin embargo, hace falta trabajo de campo más extenso con fines cartográficos, que permita mayor detalle espacial y temático, y evaluar la confiabilidad cartográficaIn order to contribute to the sea bottoms knowledge of the Seaflower Biosphere Reserve (RB Seaflower), a mapping update was made at 1:50,000 scale of the Seascape Ecological Units (SEU) for the Serrana, Roncador and Quitasueño atolls, based on the processing and interpretation of ALOS AVNIR – 2 satellite images acquired in 2012. For the attribute assignation was used as reference cartographic products, fieldwork data, and ecological descriptions of the benthic community. A total of 138,967 ha and 30 SEU, which corresponds to 32,908 ha for Serrana, 4,861 to Roncador and 101,198 to Quitasueño. The products generated represents a good approximation of the location, extension and distribution of the benthic seascape elements, constituting the base line information for the management of these atolls, they are also part of the Continental, Coastal and Marine Ecosystem Map of Colombia at scale 1:100,000 (MEC 100K) and the Colombian Coral Areas Atlas (AACC) updated on a digital platform to 2020. However, more extensive field work is needed for cartographic purposes, which allows for greater spatial and thematic detail, and to evaluate cartographic reliabilityPublishedReferee
Plankton identified in stomach contents of Oreochromis niloticus (Pisces, CICHILIDAE) and the water system of Lakes Edward, George and Kazinga channel-Uganda
No full textLake Edward is connected to Lake George by Kazinga Channel and the commercial fisheries of this water system are dominated by Oreochromis niloticus and Bagrus docmak. However, Oreochromis niloticus is on the decline in commercial catches and yet the water system may be rich in phytoplankton, the common food for Oreochromis niloticus
Spatial distribution and increase of microplastics over time in sediments of Buenaventura Bay, Colombian Pacific
No full textEl aumento de la producción, consumo y la inadecuada disposición de plásticos, han generado una acumulación de estos en los ecosistemas marinos, los cuales se han convertido en importantes sumideros de microplásticos (< 5 mm). El objetivo de esta investigación fue determinar diferencias espaciales y temporales en distribución, densidad, y tipo de microplásticos en los sedimentos de la Bahía de Buenaventura. Para esto, se tomaron muestras de sedimento en el estuario interno, cercano a los ríos, y externo, con mayor influencia marina. Las muestras se tomaron en las épocas seca, de transición y de lluvia para los años 2015 y 2019. Los microplásticos fueron extraídos mediante el método de separación por densidad; cada partícula fue clasificada y medida por microscopía óptica. La densidad fluctuó entre 11 y 1 354 partículas/kg, con promedios de 194,9 ± 51,3 y 359,6 ± 88,0 partículas/kg para los años 2015 y 2019, respectivamente, mostrando un incremento de 84,4 %. El estuario interno presentó mayor densidad en ambos años y las fibras constituyeron la forma más común de partículas: 63,7 % en 2015 y 56,03 % en 2019. La presencia y creciente acumulación de microplásticos genera riesgos y efectos adversos para las comunidades marinas; adicionalmente podría comprometer la seguridad alimentaria de las poblaciones humanas costeras.The increase in production, consumption and inadequate disposition of plastics has generated an accumulation of these elements in marine ecosystems, which have become important microplastics sinks (< 5 mm). The objective of this research was to determine the temporal and spatial differences in the density, distribution, and type of microplastics in the sediments of Buenaventura Bay. For this purpose, sediment samples were collected in the internal estuary (close to the rivers) and in the external estuary (with a greater marine influence). Samples were obtained in the dry, transition, and rainy season for the years 2015 and 2019. Microplastics were extracted by density separation method, each particle was classified and measured by optical microscopy. Density ranged from 11 to 1,354 particles/kg, with averages of 194.9 ± 51.3 and 359.6 ± 88.0 particles/kg for the years 2015 and 2019, respectively, reporting an increase of 84.4 %. The internal estuary presented a higher density in both years and the fibers constituted the most common form of microplastic particles, with 63.7 % for 2015 and 56.03 % for 2019. The presence and increasing accumulation of microplastics generates risks and adverse effects for the marine communities; additionally it coul compromise the food safety for coastal human populations.PublishedReferee
Balliella pseudocorticata (E.Y. Dawson) D.N. Young, new record of red marine alga (Rhodophyta) in Cuban waters
No full textBalliella pseudocorticata (Ceramiaceae, Ceramiales) se registra por primera vez para Cuba. Los especímenes fueron recolectados en el litoral arrecifal oriental de la provincia de Cienfuegos, centro-sur de la isla, y fueron identificados por sus características morfológicas distintivas.Balliella pseudocorticata (Ceramiaceae, Ceramiales) is reported for the first time to Cuba. Specimens were collected from the Eastern reef littoral from Cienfuegos province, South- Central part of the island, and identified on the basis of distinctive morphological characteristics.PublishedReferee
Proposal of archaeological indicators for the identification of colonial shipwreck in the Cartagena de Indias Bay
No full textAl momento de intervenir un contexto arqueológico sumergido vinculado a un naufragio, una de las primeras preguntas que surge es sobre la identidad, naturaleza y causas del hundimiento de la embarcación. Los datos que son interpretados en estos sitios subacuáticos se analizan para identificar el origen geoespacial y temporal de la nave. No obstante, en muchas ocasiones los correlatos depositados en el lecho marino no pueden aportar la información suficiente para señalar la identidad del barco. Por esto resulta fundamental establecer modelos interpretativos que tengan la capacidad de sistematizar y jerarquizar aquellas categorías de análisis que contribuyan a identificar un naufragio con un alto nivel de certeza, a partir de la vinculación de líneas de evidencia provenientes de la arqueología y la historia. En este orden de ideas, el objetivo del presente documento es exponer una propuesta metodológica construida en el marco de una investigación arqueológica desarrollada en los años recientes en un naufragio colonial ubicado en el canal de Bocachica (posible Navío San Felipe), y aplicarla a los naufragios estudiados desde una perspectiva arqueológica en el canal de Manzanillo (barco mercante) y en las proximidades de Castillogrande (posible navío conquistador), Cartagena de Indias. Dicha propuesta se fundamenta en el diseño de una matriz de indicadores arqueológicos e históricos que permitan llevar a cabo una aproximación para identificar embarcaciones naufragadas. Así pues, se hará especial énfasis en aquellos aportes que puede tener esta matriz para funcionar como una herramienta de gestión de la información sobre patrimonio cultural sumergido.When a submerged archaeological context linked to a shipwreck is intervened, one of the first questions that arises is about the identity, nature and causes of the sinking of the ship. The data that is interpreted in these underwater sites is analyzed to identify the geospatial and temporal origin of the boat. However, on many occasions the correlates deposited on the seabed cannot provide sufficient information to indicate the identity of the ship. For this reason, it is essential to establish interpretive models that have the ability of systematize and rank those categories of analysis that contribute to identifying a shipwreck with a high level of certainty, based on the linking of lines of evidence from archaeology and history. In this order of ideas, the goal of this document is to present a methodological proposal built within the framework of an archaeological research developed in recent years in a colonial shipwreck located in the Bocachica Canal (possible San Felipe Ship), and apply it to the shipwrecks studied from an archaeological perspective in the Manzanillo Canal (Merchant Ship) and in the vicinity of Castillogrande (possible Conquistador Ship) (Cartagena de Indias). This proposal is based on the design of a matrix of archaeological and historical indicators that allow an approximation to be carried out to identify wrecked vessels. Thus, special emphasis will be placed on those contributions that this matrix may have to function as an information management tool on Submerged Cultural HeritagePublishedNot Know
Identification of phytoplankton blooms in the Gerlache Strait, West Antarctic Peninsula
No full textCon la finalidad de identificar florecimientos fitoplanctónicos, se utilizó el índice de propiedades ópticas inherentes (POIíndice) en muestras de agua de la superficie y el máximo de clorofila-a (MPC) que fueron tomadas en la Tercera (enero de 2017) y en la Cuarta Expedición (enero 2018) de Colombia a la Antártida en el Estrecho de Gerlache (EG). El POIíndice se calculó partir de las anomalías espaciales estandarizadas de los coeficientes de absorción del fitoplancton, el detritus y la materia orgánica disuelta coloreada (CDOM) usando la longitud de onda 443. Además, se calculó el índice de tamaño del fitoplancton mediante la razón Azul / Rojo y este se relacionó con el POIíndice para determinar la estructura de tamaño del fitoplancton responsable de los florecimientos. En 2017 se identificó a cuatro estaciones en condiciones de florecimiento, siendo dos superficiales y dos subsuperficiales; a tres estaciones en condiciones de descenso del florecimiento y a doce en condiciones de no florecimiento, con una estructura de tamaño diversa donde predominaron poblaciones del micro, nano y del picofitoplancton. En 2018 dos estaciones se identificaron en condiciones de florecimiento, siendo uno superficial y otro subsuperficial; a dos en condiciones de descenso del florecimiento y nueve en condiciones de no florecimiento, la estructura de tamaño que dominó los florecimientos fue el microfitoplancton. Con el POIíndice, se observaron en las dos expediciones condiciones susbsuperficiales de florecimientos, probándose además su efectividad para florecimientos generados por condiciones naturales o estacionales en diferentes profundidades de la columna de agua.In order to identify phytoplankton blooms, the inherent optical properties index (IOPIndex) was used in surface water samples and the maximum chlorophyll-a (MPC) that were taken in the Third (January 2017) and in the Fourth Expedition (January 2018) from Colombia to Antarctica in the Gerlache Strait (EG). The IOPIndex is calculated from the standardized spatial anomalies of the phytoplankton, detritus and colored dissolved organic matter (CDOM) absorption coefficients using wavelength 443. In addition, the phytoplankton size index was calculated using the Blue / Red ratio and this related to the IOPIndex to determine the size structure of the phytoplankton responsible for the blooms. In 2017, four stations were identified under bloom conditions, where two were superficial blooms and two subsurface bloom; to three in conditions of decrease of the bloom and to twelve in conditions of non-bloom, with a structure of diverse size where populations of the micro, nano and the picophytoplankton predominated. In 2018, two stations were identified in bloom conditions, being one superficial bloom and the other subsurface bloom; to two in conditions of decrease in bloom and nine in conditions of non-bloom, the size structure that dominated the blooms was microphytoplankton. With the IOPIndex, subsurface bloom conditions were observed in both expeditions, also proving their effectiveness for blooms generated by natural or seasonal conditions at different depths of the water column.PublishedReferee
Recent trends in ENC and establishing new S-101 ENC specification.
No full textIn recent years, ENC has become widespread with the mandatory installation of ECDIS. On the other hand, since the specification for ENC has been established for nearly 30 years, a new S-101 ENC specification is being developed by the IHO. In this paper, along with recent trends in ENC, the author described trends in the world and the Japan Hydrographic and Oceanographic Department （JHOD）regarding this new S-101 ENC specification.PublishedReferee
Observations of sea-area volcanoes by the Japan Coast Guard between 2012 and 2020 and the associated results
No full textThe Japan Coast Guard has been observing volcanoes in the adjacent seas of Japan for safety ship navigation, volcanic disaster prevention, and securing marine interests. The target volcanoes are volcanic islands and submarine volcanoes in the Izu-Ogasawara Islands and the Ryukyu Islands, and the observations are being made using aircraft and survey vessels. Observations by aircraft are visual observations, thermal observations, and geomagnetic observations, and observations by survey vessels are topographical surveys, geomagnetic and gravity observations, water sampling, sediment dredging, and crustal structure exploration. In the last decade, large-scale eruptions have occurred on Nishinoshima Volcano and Kuchinoerabujima Volcano, and eruptive activity has continued intermittently on Suwanosejima Volcano, Sakurajima Volcano, and Satsuma-Iojima Volcano. In addition, unusual geothermal and hydrothermal phenomena were observed in Myojinsho and Aogashima. The Japan Coast Guard has endeavored to prevent volcanic disasters by appropriately observing these volcanic activities and reporting the results to The Coordinating Committee for Prediction of Volcanic Eruptions. In addition, a comprehensive survey of volcanoes is conducted in advance during calm normal times of volcanic activity for the purpose of comparison with the time of eruption. The observation of marine volcanoes has many challenges that are different from those of land volcanoes, but it is necessary to promote the sophistication of those observations while incorporating new technologies such as observations from satellites and quantitative analysis of the color tone of the discolored water.PublishedReferee