Recursos de colección

RiuNet. Repositorio institucional de la Universitat de Valencia (102.815 recursos)

RiuNet es el Repositorio Institucional de la Universitat Politècnica de València, gestionado por la Biblioteca, cuyo objetivo es ofrecer acceso en Internet a la producción científica, académica y corporativa de la comunidad universitaria con la finalidad de aumentar su visibilidad y hacerla accesible y preservable.

Mostrando recursos 1 - 20 de 84

  1. Identification of Distinct Copper Species in Cu-CHA Samples Using NO as Probe Molecule. A Combined IR Spectroscopic and DFT Study

    Concepción Heydorn, Patricia; Boronat Zaragoza, Mercedes; Millan, Reisel; Moliner Marin, Manuel; Corma Canós, Avelino
    [EN] Combining IR spectroscopy of NO adsorption on copper exchanged molecular sieves with the chabazite structure, i.e. Cu-SAPO-34 and Cu-SSZ-13, and theoretical calculations, different types of copper species have been identified. On one hand, [Cu¿OH]+ species can be accurately distinguished, characterized by a ¿NO frequency at 1788¿ 1798 cm¿1 depending on their location in the chabazite structure (6R vs. 8R) and composition (Cu-SAPO-34 vs. Cu-SSZ-13). On the other hand, dimeric copper oxo [Cu¿O¿ Cu]2+ species have been properly identified by means of DFT modelling, that proposes a ¿NO stretching frequency of 1887 cm¿1, which has been confirmed experimentally in the Cu-SAPO-34 sample. Finally the location of isolated Cu2+ ions either in the 6R units...

  2. Enhanced Stability of Cu Clusters of Low Atomicity against Oxidation. Effect on the Catalytic Redox Process

    Concepción Heydorn, Patricia; Boronat Zaragoza, Mercedes; Garcia Garcia, Saray; Fernández-Villanueva, Estefanía; Corma Canós, Avelino
    [EN] By a combination of theoretical modeling and XPS and SERS spectroscopic studies, it has been found that it is possible to stabilize metallic copper species under oxidizing reaction conditions by adjusting the atomicity of subnanometer copper clusters. Small Cu-5 clusters display low reactivity toward O-2 dissociation, being less susceptible to oxidation than larger Cu-8 or Cu-20 systems. However, in the presence of water this reactivity is strongly enhanced, leading to oxidized Cu-5 clusters. In that case, the interaction of Cu-5 with atomic O oxygen is weak, favoring recombination and O-2 desorption, suggesting an easier transfer of O atoms to...

  3. Efficient Oligomerization of Pentene into Liquid Fuels on Nanocrystalline Beta Zeolites

    Díaz-Rey, Maria Del Rocio; Paris-Carrizo, Cecilia Gertrudis; Martinez Franco, Raquel; Moliner Marin, Manuel; Martínez, Cristina; Corma Canós, Avelino
    [EN] Light alkenes oligomerization, performed in the presence of heterogeneous acid catalysts, is an interesting alternative for the production of clean liquid fuels. The process, when catalyzed by zeolites, is flexible and can be directed to the formation of oligomers in the gasoline, jet fuel, or diesel range by adjusting the reaction conditions and the zeolite's structure. Herein we show how reducing the crystal size of large-pore Beta zeolites down to 10-15 nm and controlling the number and strength distribution of their Bronsted acid sites leads to highly active and stable catalysts, selective to true oligomers within the naphtha and,...

  4. Cage-based small-pore catalysts for NH3-SCR prepared by combining bulky organic structure directing agents with modified zeolites as reagents

    Martín-García, Nuria; Paris, Cecilia; Vennestrom; Peter Nicolai Ravnborg; Thogersen, Joakim Reimer; Corma Canós, Avelino; Moliner Marin, Manuel
    [EN] It has been possible to efficiently synthesize high-silica ERI and AFX zeolites with nano-sized primary crystallites (30-200 nm). This was achieved by using a dicationic and rigid organic structure directing agent (OSDA) that fits within the large cavities of these zeolites, and the use of FAU zeolites as initial Si and Al-sources. Cu- and Fe-based ERI and AFX materials were prepared following both post-synthetic cation exchange and direct synthesis methodologies, showing good activity for the selective catalytic reduction (SCR) of nitrogen oxide using ammonia. Accelerated hydrothermal ageing of the zeolites at high temperature (i.e. 750 degrees C) shows the...

  5. Handling and treatment of male European eels (Anguilla anguilla) for hormonal maturation and sperm cryopreservation

    Herranz-Jusdado, Juan Germán; E. Kása; Kollár, Timea; Gallego Albiach, Victor; Peñaranda, D.S.; Rozenfeld, Christoffer; Pérez Igualada, Luz María; Horváth, Ákos; Asturiano Nemesio, Juan Francisco
    [Otro] During the last years, several research groups have been working on the development and improvement of new protocols for the European eel handling and maturation. As of yet, weekly injections of human chorionic gonadotropin (hCG) have proved to maturate males after just 5-6 weeks of treatment, producing high volumes of high-quality sperm during several weeks. In addition, sperm cryopreservation protocols using different extenders, cryoprotectants and cooling and thawing times have been previously described for European eel. Here, we show that Tanaka¿s extender solution can be directly used for fertilization or for cryopreservation, making unnecessary the usage of different types...

  6. Development and Experimental Validation of a TRNSYS Dynamic Tool for Design and Energy Optimization of Ground Source Heat Pump Systems

    Ruiz-Calvo, F.; Montagud, C.; Cazorla-Marín, Antonio; Corberán, José M.
    [EN] Ground source heat pump (GSHP) systems stand for an efficient technology for renewable heating and cooling in buildings. To optimize not only the design but also the operation of the system, a complete dynamic model becomes a highly useful tool, since it allows testing any design modifications and different optimization strategies without actually implementing them at the experimental facility. Usually, this type of systems presents strong dynamic operating conditions. Therefore, the model should be able to predict not only the steady-state behavior of the system but also the short-term response. This paper presents a complete GSHP system model based...

  7. Potential fuel saving in a powertrain derived from the recovery of the main energy losses for a long haul European mission

    Hervas-Blasco, Estefanía; Navarro-Peris, Emilio; De Rosa, Mattia; Corberán, José M.
    [EN] The reduction of automotive fuel consumption and emissions remains one of the main challenges. This paper presents the potential fuel saving in a CNG-powertrain derived from the recovery of the main energy losses. The analysis includes the kinetic energy recovery by a belt starter generator (BSG), the exhaust gas waste heat recuperation by using in a cascade approach, a thermoelectric generator (TEG) and a turbo-generator (TBG)- and the electrification of the main auxiliaries. An additional 48 V board net as well as the addition of a storage system are also included in the study. To support on the design...

  8. Hormonal manipulations for the enhancement of sperm production in cultured fish and evaluation of sperm quality

    Mylonas, Constantinos C.; Duncan, Neil J.; Asturiano Nemesio, Juan Francisco
    [EN] This article reviews the use of hormonal treatments to enhance sperm production in aquaculture fish and the methods available for evaluating sperm quality. The different types of testis development are examined and a brief review is presented of the endocrine regulation of spermatogenesis in fishes, including the increasing evidence of the existence of spermatozoa subpopulations. Hormonal manipulations are employed to induce spermatogenesis in species such as the freshwater eels, to synchronize maximal sperm volume to ovulation for in vitro fertilization and to enhance sperm production in species with poor spermiation. The hormones that are employed include gonadotropins (GtHs) of...

  9. Integrating Historical Operating Decisions and Expert Criteria into a DSS for the Management of a multireservoir System

    Macian-Sorribes, Hector; Pulido-Velazquez, M.
    [EN] This paper presents a collaborative framework to couple historical records with expert knowledge and criteria in order to define a Decision Support System (DSS) to support the seasonal operation of the reservoirs of the Jucar river system. The framework relies on the co-development of a DSS tool that is able to explicitly reproduce the decision-making processes and criteria considered by the system operators. Fuzzy logic is used to derive the implicit operating rules followed by the managers based on historical decisions and expert knowledge obtained in the co-development process, combining both sources of information. Fuzzy regression is used to...

  10. Thermal characterisation of compact heat exchangers for air heating and cooling in electric vehicles

    Torregrosa-Jaime, B.; Corberán, José M.; Payá-Herrero, Jorge; Delamarche, J. L.
    [EN] The use of air conditioning in all-electric cars reduces their driving range by 33% in average. With the purpose of reducing the energy consumption of the vehicle and optimising the performance of the batteries, the mobile air-conditioning can be integrated with the temperature control system of the powertrain by means of a coolant loop. In such layouts, the air-to-coolant heat exchangers must operate efficiently in both air heating and cooling modes. Dynamic simulation tools comprising the entire thermal system are essential to assess its performance. In this context, fast but accurate models of the system components are required. This paper...

  11. Economic risk assessment of drought impacts on irrigated agriculture

    Lopez-Nicolas,A.; Pulido-Velazquez, M.; Macian-Sorribes, Hector
    [EN] In this paper, we present an innovative framework for an economic risk analysis of drought impacts on irrigated agriculture. It consists on the integration of three components: stochastic time series modelling for prediction of inflows and future reservoir storages at the beginning of the irrigation season; statistical regression for the evaluation of water deliveries based on projected inflows and storages; and econometric modelling for economic assessment of the production value of agriculture based on irrigation water deliveries and crop prices. Therefore, the effect of the price volatility can be isolated from the losses due to water scarcity in the...

  12. Improved modelling of the freshwater provisioning ecosystem service in water scarce river basins

    Momblanch Benavent, Andrea; Andreu Álvarez, Joaquín; Paredes Arquiola, Javier
    [EN] Freshwater provisioning by the landscape contributes to human well-being through water use for drinking, irrigation and other purposes. The assessment of this ecosystem service involves the quantification of water resources and the valuation of water use benefits. Models especially designed to assess ecosystem services can be used. However, they have limitations in representing the delivery of the service in water scarce river basins where water management and the temporal variability of water resource and its use are key aspects to consider. Integrating water resources management tools represents a good alternative to ecosystem services models in these river basins. We...

  13. Application of Design Thinking for Technology Transfer of Remotely Piloted Aircraft Systems for the Creative Industry

    Santamarina Campos, Virginia; de-Miguel-Molina, María; de-Miguel-Molina, Blanca; Carabal-Montagud, Maria-Angeles
    [EN] With this contribution, we want to show a successful example of the application of the Design Thinking methodology, in the European project 'Technology transfer of Remotely Piloted Aircraft Systems (RPAS) for the creative industry'. The use of this methodology has allowed us to design and build a drone, based on the real needs of prospective users. It has demonstrated that this is a powerful tool for generating innovative ideas in the field of robotics, by focusing its effectiveness on understanding and solving real user needs. In this way, with the support of an interdisciplinary team, comprised of creatives, engineers and economists, together with the collaboration of prospective users from...

  14. Regulation, Co-Regulation and Self-Regulation of Civil Unmanned Aircrafts in Europe

    de-Miguel-Molina, María; Santamarina Campos, Virginia; Segarra-Oña, Marival; de-Miguel-Molina, Blanca
    [EN] Safety and security concerns play a key role during the design of civil UAs (aircraft controlled by a pilot who is not onboard it) by the producers and the offer of different services by the operators. At present, European countries have fragmented regulations about the manufacture and use of civil drones, therefore the European institutions are trying to approach all these regulations into a common one. In this sense, not only law but also ethics can give guidelines to the industry in order to obtain better reports from their clients. With our results, we would like to give advice to the European industry, as well as give new...

  15. Assessing the effectiveness of Multi-Sector Partnerships to manage droughts: The case of the Jucar river basin

    Carmona, M.; Mañez, M.; Andreu Álvarez, Joaquín; Pulido-Velazquez, M.; Haro Monteagudo, David; Lopez-Nicolas,A.; Cremades, R.
    [EN] South-east Spain is a drought prone area, characterized by climate variability and water scarcity. The Jucar River Basin, located in Eastern Spain, has suffered many historical droughts with significant socio-economic impacts. For nearly a hundred years, the institutional and non-institutional strategies to cope with droughts have been successful through the development of institutions and partnerships for drought management including multiple actors. In this paper, we show how the creation and institutionalisation of Multi-Sector Partnerships (MSPs) has supported the development of an efficient drought management. Furthermore, we analyze the performance of one of the suggested instruments by the partnership related...

  16. Coding SNPs analysis highlights genetic relationships and evolution pattern in eggplant complexes

    Acquadro, Alberto; Barchi, Lorenzo; Gramazio, Pietro; Portis, Ezio; Vilanova Navarro, Santiago; Comino, Cinzia; Plazas Ávila, María de la O; Prohens Tomás, Jaime; Lanteri, Sergio
    [EN] Brinjal (Solanum melongena), scarlet (S. aethiopicum) and gboma (S. macrocarpon) eggplants are three Old World domesticates. The genomic DNA of a collection of accessions belonging to the three cultivated species, along with a representation of various wild relatives, was characterized for the presence of single nucleotide polymorphisms (SNPs) using a genotype-by-sequencing approach. A total of 210 million useful reads were produced and were successfully aligned to the reference eggplant genome sequence. Out of the 75,399 polymorphic sites identified among the 76 entries in study, 12,859 were associated with coding sequence. A genetic relationships analysis, supported by the output of...

  17. MANMADE. Diseñando los puestos de trabajo a la medida de las personas

    Castelló Mercé, Purificación; Sánchez Palop, Luis; Sanchís Almenara, Mercedes; Solaz Sanahuja, José Salvador; Laparra Hernandez, Jose; FERRERAS REMESAL, ALBERTO; Signes Pérez, Elisa; Ruiz Folgado, Raquel
    [ES] Los trabajadores deben ser entendidos como el elemento esencial en el entorno de una fábrica. Desde esta perspectiva, se tendrá que adaptar el lugar de trabajo y la planificación de la producción a las habilidades, conocimientos y características de cada trabajador, para aprovechar al máximo el conocimiento y el potencial de los trabajadores en todos los grupos de edad y en diferentes funciones, fomentando simultáneamente una mayor seguridad en sus puestos de trabajo. Sobre esta base, el proyecto "MANufacturing through ergonoMic and Safe Antrophocentric aDaptive workplaces for context aware factoires in EUROPE. MANMADE" promueve la implantación de nuevos modelos...

  18. Enhancing Smart-Home Environments using Magentix2

    Valero Cubas, Soledad; Del Val Noguera, Elena; Alemany-Bordera, José; Botti, V.
    [EN] Multi-agent system paradigm has been envisioned as an appropriate solution for challenges in the area of smart-environments. Specifically, MAS add new capabilities such as adaption, reorganization, learning, coordination, etc. These features allow to deal with open issues in the context of smart-homes such as multi-occupancy, activity tracking or profiling activities and behaviors from multiple residents. In this paper, we present Magentix2 as a suitable MAS platform for the development of dynamic smart environments. Specifically, the use of Magentix2 (http://gti-ia.upv.es/sma/tools/magentix2/index.php) facilitates the management of the multiple occupancy in smart living spaces. Normative virtual organizations provide the possibility of defining a...

  19. Low Cost Plastic Optical Fiber Pressure Sensor Embedded in Mattress for Vital Signal Monitoring

    Sartiano, Demetrio; Sales Maicas, Salvador
    [EN] The aim of this paper is to report the design of a low-cost plastic optical fiber (POF) pressure sensor, embedded in a mattress. We report the design of a multipoint sensor, a cheap alternative to the most common fiber sensors. The sensor is implemented using Arduino board, standard LEDs for optical communication in POF (¿ = 645 nm) and a silicon light sensor. The Super ESKA® plastic fibers were used to implement the fiber intensity sensor, arranged in a 4 × 4 matrix. During the breathing cycles, the force transmitted from the lungs to the thorax is in the...

  20. Luminescence properties of the Eu2+ /Eu3 + activated Barium aluminate phosphors with varies Gd3+ concentration

    Marí, B.; Singh, K.C.; Verma, Naveen; Mollar García, Miguel Alfonso; Jindal, Jitender
    This is an Accepted Manuscript of an article published by Taylor & Francis in Transactions of the Indian Ceramic Society on 2015, available online: http://www.tandfonline.com/10.1080/0371750X.2015.1082932

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