Review of Ship Energy Efficiency

Financiado para publicación en acceso aberto: Universidade da Coruña/CISUG[Abstract] Energy efficiency has become increasingly relevant in the current economic and environmental situations. This paper aims to create a map of the state of the art of the energy efficiency on the marine sector, both in the scale of the individual ships and the entire industry. The first point of interest will be an examination of the regulatory framework of the shipping sector in regards of energy efficiency. Next there are the procedures implemented on ships with the aim of diminishing their consumption and emissions. These measures range from modifications of the design to the operational practices. Following that will be the potential advances that the industry could implement on a bigger scale to enhance the efficiency of the whole sector. Finally, an overview of the main obstacles for the implementation of these measures will be examined. While the current standards are a temporary solution and several of the most prominent improvements require further investigation, the continuous effort increases the potential of this sector for optimization. These factors emphasize the utility of this review as an introduction to help other studies have a solid understanding of the state of the art of energy efficiency in the naval industry.Xunta de Galicia; ED481A 2021/312Xunta de Galicia; ED431C 2021/3

Hybrid organic-inorganic structured materials as single-site heterogeneous catalysts

Catalyst selectivity is associated with well-defined homogeneous active sites. Transition metal complexes and organocatalysts are highly active and selective in the homogeneous phase, and their heterogenization by incorporating them into inorganic solid materials allows combining their excellent catalytic activity with improved separation, recovering and recycling properties. In this article, we present the structural characteristics and catalytic properties of hybrid organic inorganic materials in which the molecular catalysts are part of the inorganic structure, emphasizing the possibilities of periodic mesoporous hybrid materials and coordination polymers as single-site solid catalysts.We thank Spanish MICINN (Consolider Ingenio 2010-MULTICAT (CSD2009-00050) and MAT2011-29020-C02-01) and Generalitat Valenciana (PROMETEO project 2088/130) for financial support.Díaz Morales, UM.; Boronat Zaragoza, M.; Corma Canós, A. (2012). Hybrid organic-inorganic structured materials as single-site heterogeneous catalysts. Proceedings of the Royal Society A: Mathematical, Physical and Engineering Sciences. 468(2143):1927-1954. https://doi.org/10.1098/rspa.2012.0066S19271954468214

Synthesis of MgB4O7:Dy3+ and Thermoluminescent Characteristics at Low Doses of Beta Radiation

The synthesis and thermoluminescent characteristics of dysprosium-doped MgB4O7 are analyzed. The phosphor at different concentrations (0, 0.1, 0.5, 1, 2 and 4 mol%) of the dopant was prepared by the solution-assisted method. The magnesium borate compound was confirmed by X-ray diffraction. The annealing and dopant concentrations effects on the crystalline matrix were investigated. The highest thermoluminescent sensitivity was found with 450°C of annealing temperature and at high Dy3+ concentration too. The un-doped MgB4O7 phosphor shows a broad glow curve which peaked at 199°C and about 306 °C. Introducing Dy3+ dopant in the matrix that behavior was strongly changed. The wide glow curve shows three glow peaks; two small shoulders at 124 and 195 °C, and a highest peak between 323 and 336 °C temperature range. A large linear dose-response (5 ? 2000 mGy) beta dose was obtained. The complex glow curves were deconvolved and the kinetics parameters were determined considering the general order kinetics model.Fil: Legorreta Alba, Osiel. Universidad Nacional Autónoma de México. Instituto de Ciencias Nucleares; MéxicoFil: Cruz Zaragoza, Epifanio. Universidad Nacional Autónoma de México. Instituto de Ciencias Nucleares; MéxicoFil: Díaz, D.. Universidad Nacional Autónoma de México. Facultad de Química; MéxicoFil: Marcazzo, Salvador Julian. Universidad Nacional del Centro de la Provincia de Buenos Aires. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Tandil. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires. - Provincia de Buenos Aires. Gobernación. Comisión de Investigaciones Científicas. Centro de Investigaciones en Física e Ingeniería del Centro de la Provincia de Buenos Aires; Argentin

Propuesta de Entrenamiento de Red Neuronal Artificial Para la Prevención de Accidentes Carreteros

La Secretaria de Comunicaciones y Transportes (SCT) en promedio reporta 32.5 accidentes diarios en los más de 50 mil kilómetros de carreteras federales en México, lo que implica un promedio de 8 muertes diarias. Buscando minimizar este problema, la presente propuesta pretende definir las relaciones entre diferentes datos para implementar un sistema que intuya y prevenga a los automovilistas sobre incidentes en el camino, y con esto disminuir la cantidad de infortunios que se pudieran presentar. Los avisos que pudiesen ayudar a los usuarios a tomar decisiones oportunas deben ser anunciados de manera automatizada con la implementación de una red neuronal artificial (RNA), al menos los relacionados con el factor humano, problemas en el vehículo, desperfectos del camino y agentes naturales. Con base en la investigación de casos proporcionados por la SCT y la Policía Federal (PF) se calculan los pesos iniciales para la formación de la RNA, esto sirve como fundamento para describir el comportamiento del entorno. El aprendizaje se nutrirá con nuevos hechos ya sea para solidificar los pesos asignados a las entradas de la red neuronal o bien para ajustarlos. Es importante mencionar que los dispositivos tecnológicos responsables de censar los nuevos casos aplicables a la RNA deben tener la capacidad de interactuar con el entorno, esto se puede conseguir a través de vialetas solares autónomas con la capacidad de medir la temperatura, luminosidad y proximidad; y para que lo anterior tome sentido deben tener la característica de emitir alertas dependiendo de las condiciones censadas o predichas. En los países desarrollados existen múltiples propuestas que sirven para la prevención de accidentes carreteros, como las llamadas carreteras solares o los pasos de cebra inteligentes; pero estos no cuentan con mecanismos de aprendizaje continuo y menos aún con una base sólida que con su implementación garanticen la predicción de percances. The Ministry of Communications and Transportation (SCT, Secretaría de Comunicaciones y Transportes) on average reports 32.5 daily accidents in more than 50,000 kilometers of federal highways in Mexico, which equals to approximately 8 deaths daily. To minimize this problem, this proposal attempts to define the relationships between different data in order to implement a system that anticipates and prevents driver from accidents. This would thereby reduce the quantity of mishaps. These notices would help users to make timely decisions should be announced in an automated way with the use of an Artificial Neural Network (ANN), all related to the human factor, problems in the vehicle, road damages and natural agents. Based on the investigation of cases provided by the SCT and the Federal Police (PF, Policía Federal) the initial weights of the ANN are calculated. With new facts the learning will grow and the weights assigned to the inputs of the neural network will be updated. The technological devices that register the new cases must interact with the environment; this can be through autonomous solar raised reflective markers on the highway that measure temperature, luminosity and proximity. And for the above take sense they must have the characteristic of issuing alerts depending on predicted conditions. In developed countries there are multiple proposals that serve to prevent road accidents, such as solar highways or smart zebra crossings; but these don’t have continuous learning mechanisms and even less with a solid base that with their implementation guarantee the prediction of mishaps

Performance of the \u3ci\u3eLeucaena leucocephala\u3c/i\u3e–\u3ci\u3eMegathyrsus maximus\u3c/i\u3e cv Mombasa System and Local Range Grazed by Pelibuey Ewe-Lambs

Mombasa grass and leucaena have shown an excellent agronomic performance grown in tropical semi-arid ranges, the objective of this study was to compare the agronomic performance of Leucaena-Mombasa grown as a silvopastoral system at two leucaena plant densities (10000 and 15000 plants ha-1) and of Pelibuey ewe-lambs grazing it against native unimproved tropical semi-arid range of the state of Morelos, México. Experimental design was a completely random with two replications. Unimproved native range was mainly deciduous shrubs and mixed herbaceous plants (Poaceae and Asteraceae). Stocking rate was the same across treatments and grazing lasted all rainy season. Of the agronomic variables determined, both Leucaena-Mombasa systems showed the same (p\u3e 0.05) forage on-offer total and expressed as herbage-allowance but 29 and 15% higher (p≤ 0.05) respectively than the unimproved native range. Leucaena-Mombasa at the highest leucaena density showed the highest harvest rate, 22 and 50% higher (p≤ 0.05) than the registered at the lower density and unimproved native range, respectively. Unimproved native range herbaceous layer showed 40% higher (p≤ 0.05) crude protein content than the layer at both Leucaena-Mombasa systems; tree fodder was only different (p\u3c 0.05) in in vitro dry matter digestibility, tree fodder from both Leucaena-Mombasa systems was 32% higher (p≤ 0.05) than that of unimproved native range. Ewe-lambs grazing any of the Leucaena-Mombasa systems showed a daily weight gain 1.5 times higher (p\u3c 0.05) than those grazing the unimproved native range. It was concluded that Leucaena-Mombasa system is an option to improve agronomic and animal performances compare to unimproved tropical native range

On-Offer and Residual Forage in a Massai-\u3cem\u3eLeucaena\u3c/em\u3e Pasture at Different Leucaena Density

Mexican livestock producers in tropical areas are increasingly interested on the establishment of silvopastoral systems based on Leucaena (Leucaena leucocephala (Lam.) de Wit) and different tropical grasses as the Massai grass (Panicum maximum cv Massai); among questions raised on this is the importance of Leucaena density in relation to forage available. Then the objective of the study was to determine total and by species on-offer and residual forage in a grazed MassaiLeucaena pasture with different Leucaena density

REUTIVAR: Model for Precision Fertigation Scheduling for Olive Orchards Using Reclaimed Water

Olive orchard is the most representative and iconic crop in Andalusia (Southern Spain). It is also considered one of the major economic activities of this region. However, due to its extensive growing area, olive orchard is also the most water-demanding crop in the Guadalquivir River Basin. In addition, its fertilization is commonly imprecise, which causes over-fertilization, especially nitrogen. This leads to pollution problems in both soil and water, threating the environment and the system sustainability. This concern is further exacerbated by the use of reclaimed water to irrigate since water is already a nutrient carrier. In this work, a model which determines the real-time irrigation and fertilization scheduling for olive orchard, applying treated wastewater, has been developed. The precision fertigation model considers weather information, both historical and forecast data, soil characteristics, hydraulic characteristics of the system, water allocation, tree nutrient status, and irrigation water quality. As a result, daily information about irrigation time and fertilizer quantity, considering the most susceptible crop stage, is provided. The proposed model showed that by using treated wastewater, additional fertilization was not required, leading to significant environmental benefits but also benefits in the total farm financial costs

Propuesta de ampliación del programa de segregación y recolección selectiva de los residuos sólidos inorgánicos en la zona III del distrito de Ate

Ciclo Optativo de Especialización y Profesionalización en Gestión de Calidad y Auditoría AmbientalEl presente proyecto presenta la propuesta de ampliación del Programa de Segregación en la Fuente y Recolección Selectiva de los residuos sólidos inorgánicos Reciclables en la zona catastral III del distrito de Ate, como resultado del análisis del estado situacional de recuperación de los residuos sólidos, empleando toda aquella información referente a la gestión de los residuos sólidos en el distrito. Es así, que mediante el análisis de esta información se determina que existe un gran potencial de aprovechamiento de residuos sólidos reciclables como: el papel, el cartón, el vidrio, los metales y los plásticos PET y PEAD. Mediante una encuesta realizada a los habitantes de la zona III del distrito de Ate se observó que la predisposición a participar en el programa de segregación en la fuente es favorable, con un 70 por ciento de aceptación. Además se identificaron y evaluaron las vías de acceso a las agrupaciones de vivienda presentes en la zona, para determinar cuáles facilitarían el trabajo de recolección. Luego de la evaluación se seleccionaron 43 agrupaciones de vivienda como zonas priorizadas para la ampliación del programa de segregación en la fuente. Una vez seleccionado las zonas priorizadas se determinó el potencial de residuos a aprovechar. Para el año 1 y 2 ascenderían a un total de503.7 y 1,175.1 toneladas respectivamente. Luego se realizó una valoración económica producto de la comercialización de los residuos. Para el Año 1 proyectaba la suma de S/.187,138.24 Nuevos soles y el Año 2 S/.436,655.88 Nuevos soles. Asimismo se realizó la valoración ambiental producto del reciclaje de estos residuos y se determinó que se evitaría la tala de 19,431 árboles, el consumo 12,982 m3de agua, el consumo de 11‟836,732 kW de energía, la emisión de 991,591 kg de CO2 a la atmosfera, y el consumo de 172,915 litros de petróleoTesi

Spatio-temporal analysis of nitrogen variations in an irrigation distribution network using reclaimed water for irrigating olive trees

Fertigation management of olive grove is highly complex, especially when reclaimed water is used for irrigation. Nitrogen (N) is the main nutrient component of olive trees which, traditionally, has led to an excessive use in fertilization programs. This problem can be exacerbated if reclaimed water is used since it already contains N. For this reason, water quality must be considered in the fertilization plan. Both total content and N form arriving to the trees have implications in olive tree nutrient requirements as well as the environment. If reclaimed water particularities and the length of the pipes of water distribution networks are considered, the form and total concentration of N can change over space and time. In this work, both spatial and temporal analysis of the N content and form in a water distribution network using reclaimed water for irrigating olive trees was performed. This study proved that changes in N were evident both over time and across the irrigation water distribution network. Seasonally, N content was reduced during the summer period. Spatially, a clear nitrification occurred from the pumping station to the farms. These variations demonstrate the importance of a continuous water quality control in order to adjust the fertilization plan according to the N content in water

Kinetics of Thermal Degradation of Cellulose: Analysis Based on Isothermal and Linear Heating Data

[Abstarct]: In spite of the many studies performed, there is not yet a kinetic model to predict the thermal degradation of cellulose in isothermal and non-isothermal conditions for the full extent of conversion. A model proposed by the authors was tested on non-oxidising thermogravimetric data. The method consisted of initially fitting several isothermal and non-isothermal curves, then obtaining a critical temperature and an energy barrier from the set of fittings that resulted from different experimental conditions. While the critical temperature, approximately 226 °C, represented the minimum temperature for the degradation process, the degradation rate at a given temperature was related to both the critical temperature and the energy barrier. These results were compared with those observed in other materials. The quality of fittings obtained was superior to any other reported to date, and the results obtained from each single curve were in line with each other.This work was partially funded by the Spanish Ministerio de Educación y Ciencia (MTM2011-22393 and MTM2014-52876-R