The Rotary Aero-Engine from 1908 to 1918

The rotary aero engine is a special type of air-cooled radial engine, where the cylinders are arranged like the spokes of a wheel and turn around the crankshaft. The propeller is connected to the cylinders, while the crankshaft is fixed to the frame. The rotary aero engine, developed in 1908, set new standards of power and light weight within the aircraft industry. It was adopted by many pioneer aviators and widely used to set records of endurance, speed and height. Many aero engine manufacturers produced different models and variants of this type of engine, which was extensively used until the end of the First World War. The latest evolution of the rotary engine was the counter-rotary arrangement, which was devised and designed by the Siemens-Halske company. The distinctive feature of this type of engine was that the engine body (with cylinders and propeller) rotated in one direction while the crankshaft rotated in the opposite one. This result was obtained by using a bevel gear mechanism. However, rotaries were quickly and definitively replaced in 1918 by new kinds of conventional engine, which were developed in the same period by other manufacturers. The main features of rotary and counter-rotary aero engine and the performance limits that caused their decline will be described in this paper. The rotary engine will be compared with the conventional one in terms of power output, specific consumption, weight and inertia loads transferred to the frame

Africanización en Apis mellifera, estudio de toxicidad y enfermedades

La provincia de Buenos Aires concentra cerca del 50% de la producción apícola argentina, magnificando su importancia, no solo desde el punto de vista económico, sino también social y ecológico. En este sentido, el conocimiento de la introgresión de genes africanos en Buenos Aires permitiría no solo poder trazar medidas correctivas, sino también preservar la biodiversidad autóctona de abejas. Los objetivos de este trabajo son: -Realizar un relevamiento de poblaciones de abejas para determinar presencia y distribución de linajes africanizados en las zonas productoras. - Estudiar la posible relación existente entre los haplotipos encontrados y las infecciones virales más prevalentes en la provincia. - Determinar la toxicidad de plaguicidas y pesticidas más usados en agricultura para obtener información relacionada a la tolerancia a agroquímicos.Área: Ciencias Agrícolas, Produccion y Salud Anima

Lessico della cultura dialettale delle Madonie. 2. Voci di saggio

Nella prospettiva di una sistematica ricognizione del patrimonio lessicale di un'area di grande interesse etnodialettale come quella madonita e dopo il volume sulla cultura alimentare tradizionale, il volume presenta oltre 3000 voci di saggio e numerose unit\ue0 fraseologiche relative alla terminolgia connessa ai settori della cultura tradizionale. Le voci si riferiscono, in particolare, ai pi\uf9 significativi concetti dell'agricoltura e della pastorizia, ma presentano anche molti ambiti del mondo "naturale" (zoonimi, fitonimi, miconimi, meteoronimi). Il volume \ue8 corredato di carte linguistiche a colori sui principali tratti della cultura dialettale delle Madonie; il libro \ue8 arricchito da numerose illustrazioni sull'ergologia agricola e pastorale e sulla fauna locale (mammiferi, uccelli, rettili, anfibi). Il corpo del Lessico \ue8 infine integrato da numerosi etnotesti (con traduzione integrale), organizzati nella sezione "Racconti di antiche consuetudini"

Africanización en Apis mellifera, estudio de toxicidad y enfermedades

La provincia de Buenos Aires concentra cerca del 50% de la producción apícola argentina, magnificando su importancia, no solo desde el punto de vista económico, sino también social y ecológico. En este sentido, el conocimiento de la introgresión de genes africanos en Buenos Aires permitiría no solo poder trazar medidas correctivas, sino también preservar la biodiversidad autóctona de abejas. Los objetivos de este trabajo son: -Realizar un relevamiento de poblaciones de abejas para determinar presencia y distribución de linajes africanizados en las zonas productoras. - Estudiar la posible relación existente entre los haplotipos encontrados y las infecciones virales más prevalentes en la provincia. - Determinar la toxicidad de plaguicidas y pesticidas más usados en agricultura para obtener información relacionada a la tolerancia a agroquímicos.Área: Ciencias Agrícolas, Produccion y Salud Anima

Field evaluation of the efficacy and the safety of a combination of oxantel/pyrantel/praziquantel in the treatment of naturally acquired gastrointestinal nematode and/or cestode infestations in dogs in Europe

A

Experimental Model-Based Linearization of a S.I. Engine Gas Injector Flow Chart

Experimental tests previously executed by the authors on the simultaneous combustion of gasoline and gaseous fuel in a spark ignition engine revealed the presence of strong nonlinearities in the lower part of the gas injector flow chart. These nonlinearities arise via the injector outflow area variation caused by the needle impacts and bounces during the transient phenomena that take place in the opening and closing phases of the injector and may seriously compromise the air-fuel mixture quality control for the lower injection times, thus increasing both fuel consumption and pollutant emissions. Despite the extensive literature about the operation and modelling of fuel injectors, there are no known studies focused on the nonlinearities of the gas injector flow chart and on the way they can be reduced or eliminated. The authors thus developed a mathematical model for the prediction of mass injected by a spark ignition (S.I.) engine gas injector, validated through experimental data. The gas injector has been studied with particular reference to the complex needle motion during the opening and closing phases, which may strongly affect the amount of fuel injected. In this work, the mathematical model previously developed has been employed to study and determine an appropriate injection strategy in order to linearize the injector flow chart to the greatest degree possible. The injection strategy proposed by the authors is based on minimum injection energy considerations and may be easily implemented in current engine control units (ECU) without any hardware modification or additional costs. Once calibrated by means of simulation, this strategy has been validated by experimental data acquired on an appropriately equipped injector test bench. As a result, the real injector flow chart has been substantially improved, reducing its deviation from linearity to one third of the original flow chart, which is an excellent result, especially if the typical measurement dispersion of the injected mass is taken into account. The injection strategy proposed by the authors could extend the linear behaviour of gas injectors and improve the fuel supply by means of a simple software update of the ECU, thus obtaining higher engine efficiency and lower pollutant emissions

Automated classification of landforms on terraces of northeast Patagonian Massif, Argentina

Se realizó una clasificación automatizada de las geoformas en terrazas del noreste del Macizo Norpatagónico, Argentina. La clasificación se realizó mediante parametrización del relieve a partir del modelo digital de elevación del proyecto Shuttle Radar Topography Mission (NASA), a través del empleo de un Sistema de Información Geográfica. En este estudio se derivaron modelos digitales como el índice de posición topográfica (TPI) y pendiente, que se emplearon como base para la clasificación. Se realizaron sucesivos ajustes en la definición del TPI y de las reglas de clasificación de geoformas, apoyados en la supervisión de la cartografía, fotografías aéreas, imágenes satelitales y observaciones en el terreno. De acuerdo con la clasificación propuesta en este estudio, el área está dominada por las geoformas pendiente abierta y planicie, que alcanzan el 45 y 33% del área total, respectivamente. Las restantes clases geomorfológicas cubren superficies menores: lomas, cerros y sierras (8%); bajos, valles en V (7,5%); valles en U (3%) y pendiente alta (2,6%).We made an automated classification of landforms on terraces of northeast Patagonian Massif, Argentina. Classification of landforms was carried out using parameterization of the relief from the Shuttle Radar Topography Mission digital elevation model within a geographical information system. Digital models such as topographic position index (TPI) and slope derived from elevation data were employed as a basis for classification. Successive adjustments were made for TPI and classification rules, which were supervised base on aerial photographs, satellite imagery and survey of land. According to the classification proposed in the present study, the area is dominated by open slope and plain landforms, reaching 45 and 33% of the total area, respectively. The remaining classes occupy smaller areas: ridges, hills and mountains (8%), low, valleys in the form of V (7.5%); valleys in the form of U (3%) and high slope (2.6%).Fil: Genchi, Sibila Andrea. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; ArgentinaFil: Carbone, Maria Elizabeth. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; ArgentinaFil: Piccolo, Maria Cintia. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; ArgentinaFil: Perillo, Gerardo Miguel E.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Bahía Blanca. Instituto Argentino de Oceanografía. Universidad Nacional del Sur. Instituto Argentino de Oceanografía; Argentin

PROGETTAZIONE E VERIFICA SPERIMENTALE DI UNA MICROTURBINA IDRAULICA PER L\u2019INDUSTRIA ALIMENTARE

In questo articolo sono descritte le attivit\ue0 di ricerca e sviluppo di una micro-turbina idraulica inserita all\u2019interno di un macchinario che opera un nuovo processo di abbattimento della carica batterica applicabile nell\u2019industria dell\u2019imbottigliamento delle bevande. Peculiarit\ue0 della turbina progettata \ue8 la geometria della palettatura della girante, dritta ed a sviluppo puramente assiale, che ne rende estremamente economica la realizzazione. Lo scambio di energia avviene grazie al moto vorticoso impresso al fluido (swirl) mediante opportuno posizionamento dei condotti di adduzione. Lo studio della turbina \ue8 stato condotto mediante classico approccio unidimensionale, mentre il dimensionamento \ue8 stato effettuato con l\u2019ausilio di simulazioni CFD. Ultimata la progettazione, la turbina \ue8 stata realizzata e si \ue8 avviata una campagna di prove sperimentali su un banco di flussaggio appositamente allestito che ha consentito di verificare il soddisfacimento delle specifiche progettuali

Cryo-STEM-EDX spectroscopy for the characterisation of nanoparticles in cell culture media

We present a study of barium titanate nanoparticles dispersed in cell culture media. Scanning transmission electron microscopy combined with energy dispersive X-ray spectroscopy was undertaken on samples prepared using both conventional drop casting and also plunge freezing and examination under cryogenic conditions. This showed that drying artefacts occurred during conventional sample preparation, whereby some salt components of the cell culture media accumulated around the barium titanate nanoparticles; these were removed using the cryogenic route. Importantly, the formation of a calcium and phosphorus rich coating around the barium titanate nanoparticles was retained under cryo-conditions, highlighting that significant interactions do occur between nanomaterials and biological media