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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
411

Využití stavebních recyklátů pro čištění odpadních vod / The Use of Recycled Building Materials for Wastewater Treatment

Zedník, Ondřej January 2020 (has links)
The constantly tightening wastewater treatment legislation require high-quality runoff from small-scale producers of pollution who are typically represented by small municipalities up to 500 inhabitants or decentralized parts of larger municipalities. Small municipalities are faced with high investment-intensity associated with the acquisition of new wastewater treatment plant. After several years of development, today natural technologies of wastewater treatment are in competition with mechanical-biological treatment plants. Natural technologies can even achieve better results than popular biological treatment plants. However, natural technology does not eliminate the main investment limit connected with the acquisition of wastewater treatment plant. If there was cheaper solution connected with using alternative filter materials (in our case recycled construction and demolition waste), small municipalities could take constructed wetland without large subsides. At the same time, the use of recycled construction and demolition wastes will lead to benefits in the field of sustainable urban development and replacement of non-renewable materials. Despite these benefits, recycled aggregates have never been considered as alternative filter materials for natural wastewater treatment plants. For that reason, the aim of diploma thesis is to assess the possibility of applying recycled aggregates for wastewater treatment which will include evaluation of real trial operation.
412

Zdravotně technické instalace a plynovod v polyfunkčním objektu / Sanitary technical installations and gas pipeline in a multifunctional building

Bartek, Vojtěch January 2020 (has links)
Diploma thesis deals with sanitation installations and gas installations in polyfunctional building in Miroslav. Polyfunctional building has four overground floors and one basement. The apartments are located on all overground floors and the offices are located on first over-ground floors. In the theoretical part discusses about the recycling of water and its use.
413

Využití asfaltových a betonových recyklátů do pozemních komunikací / The usage of asphalt and concrete recycled materials to roads

Svrčina, Vít January 2015 (has links)
Currently it is important to address the re-use of building materials from construction reconstructed or upgraded roads. Commonly used technologies cold and hot asphalt recycling are starting using to complement with technologies using cold asphalt mixtures with rejuvinators or softeners. This type of asphalt mixtures could be used in pavement constructions with lower traffic load. This thesis deals with the design and laboratory assessment of unbound and bound mixtures R-material and recycled concrete. This thesis is experimentally testing the possibility of using functional tests to optimize the design of asphalt mixture with 100% representation of R-material with a possible revival of asphalt emulsion with a rejuvenator.
414

Energetické využití recyklovaných rostlinných olejů / Utilizing of recycled green oils for power generation

Mikula, Hynek January 2010 (has links)
his thesis deal with the processing of used vegetable oil. Its recycling and power generation in the cogeneration unit. Economic and energy balance process. Proposal for a heat exchanger for heating vegetable oil. Physical properties of rapeseed oil.
415

Optimalizace složení betonů s využitím plniv z recyklovaných betonů / Optimization of the concrete composition with the use of recycled concrete aggregates

Skriňáková, Eva January 2016 (has links)
Concrete as a building material is subject to continuous innovation and thanks to advanced technology and quantum of research, its properties are still improved. It is logical that the more concrete we produce, the more waste it arises. The volume of this waste can not be stored in landfills endlessly, nowadays most of the waste economies in the world are trying to recycle concrete rubble. The recycling is not such a problem, the technology has been long verified but the quality of the recycled concrete aggregate is unquestionably one of the primary assumption which leads to accomplish required properties of concrete. In fact, the recycling process is „crushing“ the concrete into particles with an effort to eliminate the cement paste on the surface of the aggregate. An ideal solution would be create a resistant and firm coating that would adhere perfectly to the cement matrix. This diploma thesis is focused on the properties of recycled concrete aggregate and methods of improvement and optimization of the concrete mix composition.
416

Studium vlastností polymery modifikovaných malt využívající pucolánově aktivní materiály / Study of the Properties of Polymer-modified Mortars using Pozzolana Active Admixtures

Pyreňová, Eliška January 2016 (has links)
This diploma thesis is focused on the study of the properties of polymer-modified cementitious mortars which using pozzolanic active materials based on amorphous silica. Explores the possibilities of using the recycled glass as a partial replacement of cement in PMM. Properties of mortars are reviewed in mineralogical and technological point of view. For specification of the results were used the analysis RTG, DTA and REM.
417

Plan de Negocio para la distribución de bolsas de papel reciclado como medio publicitario en bodegas, mini-markets y puestos de mercado de Lima Metropolitana / Business Plan for a company that distributes recycled paper bags as printed advertising in grocery stores, mini-markets and market stalls in Lima.

Noguera de las Casas, Ana Vanessa, Orams Camacho, Edgar Alfred, Perea Isasi, Cinthya Paola 27 August 2020 (has links)
A través del presente trabajo de investigación, buscamos sustentar la deseabilidad, viabilidad y rentabilidad del Modelo de Negocio de Innobag Perú, que tiene como objetivo la distribución gratuita de bolsas de papel reciclado con publicidad impresa a bodegas, mini-markets y puestos de mercado en Lima Metropolitana. Innobag Perú busca contribuir con la reducción en el consumo de bolsas plásticas, atacando y aprovechando uno de los principales momentos de uso, generando ahorros en los establecimientos e incrementando la atractividad de nuestro producto. Completamos nuestra propuesta de valor, convirtiendo estas bolsas de papel reciclado en un medio para que las empresas anunciantes publiciten su marca de manera efectiva y directa en un momento de alto uso asegurando la viabilidad de nuestro modelo de negocio. A través de un sondeo realizado entre consumidores, administradores de bodegas, mini-markets y puesto de mercado; y decisores de inversión en publicidad de empresas anunciantes, hemos logrado validar la deseabilidad de nuestro modelo de negocio. Nuestro análisis económico financiero, nos ha permitido validar la rentabilidad del modelo, esperando un VAN de S/ 114,202 y una TIR de 81.26%. / Through this research work, we seek to support the desirability, feasibility and profitability of the Innobag Peru Business Model, which aims to distribute free recycled paper bags with printed advertising to grocery stores, mini-markets and market stalls in Lima. Innobag Peru seeks to contribute to the reduction in the consumption of plastic bags taking advantage of one of the main moments of its use, generating savings for the owners of these establishments and increasing the attractiveness of our product. We complete our value proposition by turning these recycled paper bags into a mean for companies to advertise their brand effectively and directly at a time of high use, ensuring the viability of our business model. Through our market research conducted among consumers, decision makers of investment in advertising as well as managers of grocery stores, mini-markets and market stalls, we have validated the desirability of our business model. Our financial and economic analysis allowed us to validate the profitability of the model, expecting an NPV of S / 114,202 and an IRR of 81.26%. / Trabajo de investigación
418

Estudio experimental de mejoramiento de las propiedades de resistencia al corte de un suelo expansivo con polvo de vidrio reciclado y fibras de polipropileno en la ciudad de Talara, departamento de Piura

Pusari Quispe, Oscar Alonso, Rodriguez Machuca, Joao Yhazzir 07 December 2020 (has links)
Los resultados del estudio que se expone en la presente tesis, tratan sobre las arcillas expansivas en “Talara”, en base a resultados obtenidos en los ensayos de laboratorio como el Análisis Granulométrico por Tamizado, ensayo de Límite Líquido, Límite Plástico e Índice de Plasticidad, ensayo de Proctor modificado y el ensayo Corte Directo. Cabe decir que dichos ensayos se realizaron tomando como punto de partida las características geológicas, geomorfológicas, geotécnicas y la evaluación de daños en las diversas estructuras de la zona como viviendas producto de la expansión y consolidación del terreno. La problemática se origina a raíz del suelo arcilloso, ya que la principal característica que puede tener ese tipo de suelo es que sea un suelo expansivo, por lo tanto, se debe tener en consideración mejorar el suelo para evitar posteriormente daños estructurales. En la investigación se describirán las principales consecuencias y factores que intervienen en el fenómeno de la expansión y el cómo enfrentar a este tipo de suelo. El presente estudio busca la mejora del suelo mediante una técnica innovadora, eco amigable y factible como es la estabilización física usando el vidrio reciclado y las fibras de polipropileno (materiales de desecho en las operaciones de la construcción), ya que en la actualidad estos dos tipos de materiales generan un impacto negativo en el medio ambiente, por lo cual se trata de reutilizar dichos materiales en el mejoramiento del suelo. El estudio se basó en una muestra de suelo medianamente expansivo, debido al registro del Límite Líquido, Límite Plástico e Índice de Plasticidad, extraído de la Urbanización Sudamérica, localizado en Talara, Piura con el fin de mejorarlo, para luego verificar el comportamiento de mejora de las propiedades de resistencia al corte del suelo. Como parte del desarrollo de la investigación se realizaron los diversos ensayos para comprobar con datos numéricos la mejora del suelo, otorgando porcentajes de sustitución con respecto al peso seco (0%, 5%, 6% y 7.5%) a la muestra en estado natural. Finalmente, se obtuvieron las mejoras de las propiedades de resistencia al corte con un porcentaje de sustitución equivalente a 5%, el cual registra las mejoras en cohesión y ángulo de fricción. / The results of the study that is presented in this thesis, deals with the expansive clays in "Talara", based on results obtained in laboratory tests such as the Granulometric Analysis by Screening, Liquid Limit test, Plastic Limit and Plasticity Index, modified Proctor test and the Direct Cut test. It is possible to say that these tests were carried out taking as a starting point the geological, geomorphological, geotechnical characteristics and the evaluation of damages in the different structures of the area as houses product of the expansion and consolidation of the land. The problem originates from the clay soil, since the main characteristic that this type of soil can have is that it is an expansive soil, therefore, it is necessary to consider improving the soil to subsequently avoid structural damage. The research will describe the main consequences and factors involved in the phenomenon of expansion and how to deal with this type of soil. The present study seeks to improve the soil through an innovative, eco-friendly and feasible technique such as physical stabilization using recycled glass and polypropylene fibers (waste materials in construction operations), since these two are currently Types of materials generate a negative impact on the environment, so it is about reusing these materials in soil improvement. The study was based on a sample of moderately expansive soil, due to the registry of the Liquid Limit, Plastic Limit and Plasticity Index, extracted from the South American Urbanization, located in Talara, Piura in order to improve it, and then verify the improvement behavior of the properties of resistance to the cut of the floor. As part of the development of the research, the various tests were carried out to verify the improvement of the soil with numerical data, granting replacement percentages with respect to dry weight (0%, 5%, 6% and 7.5%) to the sample in its natural state . Finally, the improvements of the properties of resistance to the cut with a percentage of substitution equivalent to 5% were obtained, which records the improvements in cohesion and angle of friction. / Tesis
419

Détermination de la contamination microbiologique des litières de fumier recyclé en filière de production bovine en fonction des pratiques de productions et de gestion en élevage.

Beauchemin, Jessika 08 1900 (has links)
La litière de fumier recyclé (LFR) est utilisée dans les fermes canadiennes comme alternative à la litière conventionnelle de paille. Elle est obtenue par l’extraction de la fraction solide du fumier des vaches, parfois suivie par une maturation. Toutefois, les caractéristiques microbiologiques de cette litière sont peu documentées. Ainsi, cette étude a permis la description du microbiote et des caractéristiques microbiologiques de la LFR comparativement à la paille, avant et après leur utilisation, et d’évaluer l’impact de différentes méthodes de production de la LFR sur ces écosystèmes. Les résultats des analyses du microbiote ont démontré que la richesse et la diversité du microbiote de la LFR avant utilisation étaient différentes de celles de la paille. Les litières de fumier recyclé avant et après utilisation possédaient une diversité microbienne moindre comparativement à celles mesurées pour la paille avant et après utilisation. Aussi, les différentes méthodes de production de la LFR n’influençaient pas la richesse du microbiote, mais influencent sa composition. La méthode de production utilisant la séparation suivie d’une maturation en amas possédait une charge bactérienne moindre que celle utilisant la séparation suivit d’une maturation en boîte. Finalement, la LFR contenait plus de Listeria monocytogenes et de Salmonella spp que la litière de paille. Cela permet de conclure que la LFR, actuellement produite dans les fermes de l'Est du Canada, constitue un risque microbiologique plus élevé que la litière de paille. / Recycled manure solid bedding (RMS) is used on Canadian farms as an alternative to conventional straw bedding. RMS is obtained by extracting the solid fraction of dairy cow manure, sometimes followed by maturation. However, the microbiological characteristics of this bedding are poorly documented. This study allowed the description of the microbiota and microbiological characteristics of RMS compared to straw and assessed the impact of the RMS production methods on its microbiota. The results of the microbiota analyses demonstrated that the richness and diversity of the microbiota in unused RMS were different from unused straw. Unused RMS and used RMS possessed more similar microbial diversity compared to the microbial diversity between unused and used straw. Moreover, the different RMS production methods did not influence the richness of the microbiota but influence its composition. The RMS production method using separation followed by heap maturation had a lower bacterial load than production method using separation followed by box maturation. Finally, RMS contained more Listeria monocytogenes and Salmonella spp than straw bedding. This leads to the conclusion that RMS bedding currently produced on farms in Eastern Canada, clearly constitute a greater microbiological risk as compared to straw bedding.
420

Maîtrise de l’eau efficace dans les bétons de granulats recyclés / Control of effective water in recycled aggregates concretes

Khoury, Eliane 07 December 2018 (has links)
Constitués de plusieurs composants (granulats naturels et pâte de ciment adhérente), les GBR ne sont à l’heure actuelle pas utilisés largement dans la formulation de nouveaux bétons. Les propriétés médiocres des GBR compliquent considérablement la détermination de la quantité d’eau efficace dans le béton frais. Tout d’abord, une étude bibliographique va mettre en évidence la grande dispersion des résultats des essais de caractérisation des GBR et des propriétés des bétons recyclés à l’état frais et durci. Ensuite, une étude vise à analyser l’hétérogénéité des GBR et des granulats de béton concassé (GBC) par rapport à différents paramètres : aux impuretés granulaires, à la densité et à la teneur en pâte de ciment, au malaxage du béton parent, et au niveau de la capacité d’absorption d’eau des GBC en fonction de leur état de pré-humidification. Enfin, une dernière partie est destinée à améliorer la maîtrise de l’eau efficace réelle dans la fabrication du béton recyclé. La cinétique d’absorption des GBC dans une pâte de ciment est tout d’abord étudiée. Ensuite, l’évolution de l’eau efficace durant le malaxage de bétons à base de GBC est investiguée au moyen d’une méthode originale basée sur le suivi des courbes de puissance du malaxeur. Finalement, l’effet d’un malaxage sous vide relatif sur les propriétés des bétons à base de granulats naturels et des bétons à base de GBC est étudié. / Composed of several components (natural aggregates and adherent cement paste), RCA are not widely recommended in new concrete formulations. Their poor properties considerably complicate the determination of the effective water in fresh concrete. In a first part, a bibliographic study will highlight the wide dispersion of the results of characterization tests of RCA and the properties of fresh and hardened recycled concrete. In a second part, the heterogeneity of RCA and crushed concrete aggregates (CCA) is studied according to different parameters: granular impurities, density, cement paste content, mixing of parent concrete, and water absorption capacity according to their pre-humidification. The third part consists of three experimental studies that intend to improve effective water control in the manufacture of recycled concrete. The absorption kinetics of CCA in a cement paste is first studied. Then, the evolution of effective water in fresh concrete during mixing is studied using an original method based on the power evolution of the mixer. Finally, the effect of vacuum mixing on the properties of ordinary and recycled concretes is investigated.

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