Tesis: "Sustainable raw materials"

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Rogetzer, Patricia, Lena Silbermayr y Werner Jammernegg. "Sustainable sourcing of strategic raw materials by integrating recycled materials". Springer Nature, 2018. http://dx.doi.org/10.1007/s10696-017-9288-4.

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In this paper we investigate a manufacturer's sustainable sourcing strategy that includes recycled materials. To produce a short life-cycle electronic good, strategic raw materials can be bought from virgin material suppliers in advance of the season and via emergency shipments, as well as from a recycler. Hence, we take into account virgin and recycled materials from different sources simultaneously. Recycling makes it possible to integrate raw materials out of steadily increasing waste streams back into production processes. Considering stochastic prices for recycled materials, stochastic supply quantities from the recycler and stochastic demand as well as their potential dependencies, we develop a single-period inventory model to derive the order quantities for virgin and recycled raw materials to determine the related costs and to evaluate the effectiveness of the sourcing strategy. We provide managerial insights into the benefits of such a green sourcing approach with recycling and compare this strategy to standard sourcing without recycling. We conduct a full factorial design and a detailed numerical sensitivity analysis on the key input parameters to evaluate the cost savings potential. Furthermore, we consider the effects of correlations between the stochastic parameters. Green sourcing is especially beneficial in terms of cost savings for high demand variability, high prices of virgin raw material and low expected recycling prices as well as for increasing standard deviation of the recycling price. Besides these advantages it also contributes to environmental sustainability as, compared to sourcing without recycling, it reduces the total quantity ordered and, hence, emissions are reduced.

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2

Hamood, Alaa. "Sustainable utilisation of raw sewage sludge (RSS) as a water replacement in cement-based materials containing unprocessed fly ash". Thesis, University of Wolverhampton, 2014. http://hdl.handle.net/2436/332182.

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Prior to the implementation of the European Union Urban Waste Water Treatment Directive (91/271/EEC) in 31 Dec 1998, around a quarter of the sewage sludge produced in the UK was either discharged to surface waters via pipes or disposed from ships at sea. Discontinuing this route together with the quality requirements of the European Waste Water Directive, led to the generation of significant quantities of sewage sludge. It has therefore become required to treat this waste effectively before it can be sent back to the environment. Consequently, this added greater challenges for the environmental agencies, as well as local authorities. The treatment process comprises costly and energy consuming applications including physical, chemical, biological and thermal. In addition to the sewage sludge, the power generation industry produces massive quantities of fly ash from burning coal. In the UK, there is about 5,300,000 tonnes of fly ash that are generated annually, which require to be processed and classified in order to meet the standard requirements before it can be used in the construction applications. The classifying process also involves a series of costly and energy consuming mechanical and physical applications. This research programme has introduced an innovative alternative to the traditional re-use and disposal routes of Raw Sewage Sludge (RSS) and unprocessed fly ash. It has suggested the utilisation of RSS and unprocessed fly ash as raw ingredients for the production of sustainable construction materials. This research programme has therefore examined the performance of cement-based materials containing Raw Sewage Sludge (RSS) as a water replacement and unprocessed fly ash as cement replacement. Mortar and concrete mixes incorporating these materials were tested for their flowability/workability, density, Total Water Absorption (TWA), Ultrasonic Pulse Velocity (UPV), compressive strength, flexural strength, drying shrinkage, sulphate attack and leaching properties. Three series of cement-based materials were studied including mortar mixes with RSS and unprocessed fly ash (Series 1), mortar mixes with RSS and large proportions of unprocessed fly ash (Series 2), and concrete mixes with RSS and unprocessed fly ash (Series 3). The outcomes of the investigation were encouraging in that cement-based materials containing RSS and unprocessed fly ash that were produced demonstrated relatively good engineering, durability and environmental properties in comparison to the control mixes. The inclusion of unprocessed fly ash significantly reduced flowability/workability; however it improved long-term compressive strength for both mixes with RSS and water. The best compressive strength results were recorded when cement was replaced with 10-20% unprocessed fly ash by weight of total binder. The results also showed that sulphate attack resistance improved when fly ash was included. Moreover, safe concentration levels of heavy metals and free ions were detected when leaching test was performed. However, it must be kept in mind that more environmental tests must be performed before any large scale use is undertaken.

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AMATO, ALESSIA. "Innovative and sustainable strategies of urban mining". Doctoral thesis, Università Politecnica delle Marche, 2017. http://hdl.handle.net/11566/245303.

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La gestione di un’enorme quantità di rifiuti da apparecchiature elettriche ed elettroniche (RAEE), rappresenta un problema rilevante per la nostra società, poichè rischi per l’ambiente e la salute umana, legati ad una scorretta gestione, sono combinati con la perdita di materiali valorizzabili. Questo lavoro ha per oggetto lo sviluppo di processi sostenibili per il recupero di metalli di valore dai RAEE: in particolare, è stata effettuata un’indagine in laboratorio mirata all’estrazione, da schermi a cristalli liquidi, di indio, un metallo recentemente classificato dalla Commissione Europea tra i “critical raw materials”. La sperimentazione ha permesso l’ottimizzazione di un processo con rese di recupero di indio superiori al 90%, basato su operazioni idrometallurgiche. E’ stato studiato inoltre il processo dal punto di vista della sua sostenibilità ambientale, confrontandone l’impatto con quello degli attuali sistemi di gestione degli schermi a cristalli liquidi . La valutazione ha evidenziato che il ciclo di gestione delle acque di processo e pre-trattamenti fisici del pannello finalizzati alla concentrazione del metallo, rappresentano dei fattori chiave per la sostenibilità ambientale del processo. Il lavoro è stato svolto nel contesto di un progetto finanziato dalla Commissione Europea nell’ambito del 7FP, denominato HydroWEEE. Tale progetto aveva per obiettivo la realizzazione di un impianto mobile, con caratteristiche flessibili per il recupero di metalli da diversi RAEE: indio da TV/monitor a cristalli liquidi, ittrio da lampade e tubi catodici, rame oro e argento da circuiti stampati, cobalto da batterie litio-ione. L’attività di ricerca è stata anche finalizzata a valutare la sostenibilità ambientale dei vari processi realizzati nell’impianto mobile, evidenziandone un generale vantaggio (tra il 20 e l’80%) rispetto alla produzione primaria dei metalli. La valutazione dei rischi per i lavoratori nell’impianto mobile conclude lo studio.
The management of a huge quantity of waste from electric and electronic equipment (WEEE) represents a critical issue for the modern society. The negative environmental and health effects due to the improperly management are combined with the loss of valuable materials. The present work focused on the recovery of metals from WEEE with particular attention to indium from end-of-life liquid crystal displays (LCD). The experimental section allowed the optimization of a process that includes an acid leaching characterized by an innovative cross-current design, followed by a cementation with zinc powder. Considering the satisfying efficiencies obtained on the lab scale, higher than 90%, the whole process was studied from an environmental point of view comparing its emissions with those produced by the current management strategies (disposal in landfilling sites, incineration and traditional recycling). A life cycle assessment (LCA) of the different scenarios proved the significant advantage of recycling ways. Moreover, the traditional recycling resulted to be the most favorable, due for both the relevant water consumption of the innovative treatment and to the low indium content in the LCD. Nevertheless, a simple water recirculation system, combined with a physical indium upgrading in the waste, make the innovative option the best choice. The simple design of the optimized process allows its implementation in a mobile plant, built within the European project, HydroWEEE. The plant mobility prevents the impacts due to the waste transport, that contributes to the 30-40% of the currently treatments. Furthermore, this advantage is combined with the possibility to treat several WEEE for the recovery of different metals. The sustainability of this approach was proved by a LCA that highlighted the positive effect also in the comparison with the primary production, with a benefit between 20 and 80%. Last, but not least, the risk for workers in the real mobile plant was assessed.

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4

Maccaferri, Cristian. "Valorization and recycling of raw materials through a waste management system, case of study Koinonia Community, Lusaka, Zambia". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2017. http://amslaurea.unibo.it/13571/.

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This thesis presents the implementation and the optimization of a waste management system (WMS) in the Koinonia community (that is sited in the Chilanga district near Lusaka), showing the challenges that must be faced, implementing a WMS in a developing country. In the first part of the thesis it will be contextualized the waste management in the Zambian economy showing how a diversification involving the it could fit with the needs of the Nation. In the second part it will be treated the waste management hierarchy through the illustration of some European policies (like Circular Economy Package) and best practice (like WtE in Sweden). In the third part it will be analyzed the case of study Koinonia community where it has been spent three month. The object of the study was how to make the waste management system economical sustainable, the various issue regarding this subject are described by some reports wrote at the beginning of the experience and at the end. In addition, the chapter presents a study about the waste production in Chilanga and the data collected by means the interview with the waste aggregator present in the city. Concluding, it is showed a proposal of evolution of the waste management system which consist in install a phv (Photovoltaic) system that will feed an ecological island of low dimension.

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Boullenger, Garance <1996&gt. ""How do agri-food companies define sustainability criteria for their raw materials purchasing? Study of wheat sustainable sourcing within biscuits producing companies."". Master's Degree Thesis, Università Ca' Foscari Venezia, 2019. http://hdl.handle.net/10579/15553.

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6

Gianni, Lorenzo. "Electrodialytic recovery of tungsten and cobalt from tungsten carbide scrap". Master's thesis, Alma Mater Studiorum - Università di Bologna, 2022.

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Critical raw materials (CRMs) are essential for a wide range of European industrial ecosystems. Access to critical resources is necessary for Europe’s ambition to achieve climate neutrality and deliver the Green Deal. However, supply of material from primary sources is putting extreme pressure on the planet through greenhouse gas emissions, biodiversity loss and water stress. In this scenario, promoting circular economy by obtaining resources from secondary sources is therefore essential to reduce the environmental burden posed by raw material primary extraction and to secure the supply chain of CRMs. This work is a preliminary assessment on the potential of the electrodialytic (ED) treatment in alkaline condition on a tungsten carbide scrap powder obtained from end-of-life cutting tools industry for the recovery of two CRMs: Tungsten (W) and Cobalt (Co). Modular ED reactors with 2 or 3 cell compartments have been used to perform eleven ED experiments (each lasting 24 h), with either NaOH or NH4OH and at 100, 150 or 200 mA to individuate the best reactor configuration, alkaline reagent, and current intensity. The alkaline reagents were placed at different concentrations in the anode compartment (in case of 2-compartments reactor) or in the central compartment (in case of a 3-compartments reactor) along with 450 mL of deionized water and the solid matrix with a solid:liquid ratio of 1/50. Inductively coupled plasma-atomic emission spectroscopy was used to quantify the amount of W and Co obtained in solution at the end of the experiments. The experiments showed that the 2-compartments ED cell setup at 100 mA and with NaOH 0.1 M resulted in the highest W dissolution ( 651 mg), and that the 3-compartments ED cell setup at 100 mA and with NaOH 0.01 M resulted in the highest Co dissolution ( 372 mg) and electromigration (85%). Further investigation is needed to optimize the operational parameters.

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7

Melikoglu, Mehmet. "Production of sustainable alternatives to petrochemicals and fuels using waste bread as a raw material". Thesis, University of Manchester, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.488783.

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8

Dvořák, Jakub. "Návrh objektu využívajícího alternativní materiály se zohledněním požadavků na trvale udržitelný rozvoj". Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2019. http://www.nusl.cz/ntk/nusl-396157.

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This diploma thesis deals with the design of a small family house, which construction uses alternative building materials. The first part of the thesis is devoted to the world, European and Czech legislation related to sustainable development. The concept of ecological construction, which focuses on the possibilities of reducing the negative impacts of construction production on the environment at various stages of construction and on energy, material, water and waste management, is also presented. The thesis also describes advantages and disadvantages of particular solutions. In the second part of the thesis, which based on theoretical knowledge, is the design of a family house from alternative materials worked out. The design of the study in the scale of 1:100 consists of measured floor plan drawings of all storeys, characteristic measured section drawings, layout plans with displayed furniture and equipment, elevation drawings of particular facades, roof drawings and situation design. The drawing part is accompanied by a text part. The processed design is compared to the reference building and then evaluated from the point of view of functional, economic, environmental and social requirements.

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9

MAZZONI, GIORGIA. "Self-healing potential and RAP inclusion as sustainable strategies for never-ending bituminous materials". Doctoral thesis, Università Politecnica delle Marche, 2018. http://hdl.handle.net/11566/252978.

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Benefici economico-ambientali incoraggiano l’uso di fresato (RAP), proveniente dalla demolizione di vecchie pavimentazioni stradali, da introdurre nella produzione di nuove miscele. In particolare, riciclare a caldo il RAP permette una riduzione dei costi di produzione e dei problemi di smaltimento, oltre a un risparmio delle risorse naturali, grazie allo sfruttamento della fase sia bituminosa sia litica. Tuttavia, i regolamenti delle agenzie stradali e pubbliche amministrazioni impongono restrizioni sulle percentuali di RAP implementabili (10÷30%) per la scarsa conoscenza dei meccanismi di interazione tra bitume riattivato da RAP e bitume vergine. Assunzioni inaccurate possono causare ammaloramenti prematuri della miscela, come fessurazioni da fatica, data la più severa ossidazione, e conseguente rigidezza, del bitume da RAP rispetto a quello vergine. In questo contesto, l’attività di dottorato si è posta l’obiettivo di valutare gli effetti causati dal riciclaggio a caldo di alti quantitativi di RAP. Poiché la prestazione in sito di miscele bituminose è strettamente legata alla fase legante e ai suoi costituenti (filler e bitume), la sperimentazione è stata indirizzata all’analisi delle interazioni tra diverse tipologie e dosaggi di bitumi da RAP, rigeneranti e filler. Accanto alla “classica” caratterizzazione reologica, protocolli di prova innovativi sono stati applicati per ottenere un quadro globale del comportamento dei materiali e comprensivo di risposta a fatica, self-healing e tixotropia. Sulla base delle evidenze sperimentali, l’impiego di un maggior contenuto di RAP è possibile, senza l’insorgenza di effetti dannosi sulla miscela finale, con una corretta progettazione. La tecnica di produzione, stesa e compattazione, la provenienza e le proprietà del RAP e dell’eventuale rigenerante devono essere selezionate opportunamente per migliorare le proprietà della miscela alle basse e intermedie temperature senza comprometterne le prestazioni alle alte temperature.
Economic and environmental advantages encourage the use of Reclaimed Asphalt Pavement (RAP), coming from the milling of old pavements, to be introduced in new bituminous mixture. In particular, hot recycling of RAP allows a reduction of production costs and disposal issues as well as natural resources conservation thanks to the exploitation of both bituminous and lytic component. However, regulations of road agencies and public administrations usually impose restrictions on RAP percentages (from 10 to 30%) due to uncertainties concerning the interaction between bitumen released from RAP and virgin bitumen. Inaccurate assumptions on the related effects could lead to mixtures subjected to premature distresses, such as fatigue failure, considering the higher oxidation, and consequently viscosity (stiffness), of aged bitumens if compared to that of virgin bitumens. In this context, the Ph.D research aimed at evaluating the effects caused by hot recycling of high RAP contents. Since it is expected that field performance of bituminous mixtures is mainly led by mastic phase and its components (i.e. filler and bitumen), the experimental study focused on analysing interactions among different types and dosages of RAP bitumens, rejuvenators and fillers. Besides the “classical” rheological characterisation, more innovative tests and analyses were performed in order to get an overall picture of the mechanical behaviour of the materials investigated in terms of fatigue, self-healing and thixotropy. Based on the overall findings, the inclusion of higher RAP contents appears possible, without negatively affecting the final mixture performance, when an appropriate design is considered. Production process, paving technology, source, properties and dosage of RAP and, eventually, rejuvenator need to be properly selected so as to improve low and intermediate temperature properties of the mixture without penalising its high temperature performance.

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Eisenmenger, Nina, Dominik Wiedenhofer, Anke Schaffartzik, Stefan Giljum, Martin Bruckner, Heinz Schandl, Thomas Wiedmann, Manfred Lenzen, Arnold Tukker y de Koning Arjan. "Consumption-based material flow indicators - Comparing six ways of calculating the Austrian raw material consumption providing six results". Elsevier, 2016. http://epub.wu.ac.at/6684/1/ECOLEC.pdf.

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Understanding the environmental implications of consumption and production depends on appropriate monitoring tools. Material flow accounting (MFA) is a method to monitor natural resource use by countries and has been widely used in research and policy. However, the increasing globalization requires the consideration of "embodied" material use of traded products. The indicator raw material consumption (RMC) represents the material use - no matter where in the world it occurs - associated with domestic final demand. It provides a consumption-based perspective complementary to the MFA indicators that have a territorial focus. Several studies on RMC have been presented recently but with diverging results; hence, a better understanding of the underlying differences is needed. This article presents a comparison of Austrian RMC for the year 2007 calculated by six different approaches (3 multi-regional input-output (MRIO) and 3 hybrid life-cycle analysis-IO approaches). Five approaches result in an RMC higher than the domestic material consumption (DMC). One hybrid LCA-IO approach calculates RMC to be lower than DMC. For specific material categories, results diverge by 50% or more. Due to the policy relevance of the RMC and DMC indicators it is paramount that their robustness is enhanced, which needs both data and method harmonization.

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Giljum, Stefan, Martin Bruckner y Aldo Martinez. "Material Footprint Assessment in a Global Input-Output Framework". Wiley, 2014. http://dx.doi.org/10.1111/jiec.12214.

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Material flow-based indicators play an important role in indicator sets related to green and resource-efficient growth. This paper examines the global flows of materials and the amounts of materials directly and indirectly necessary to satisfy domestic final demand in different countries world-wide. We calculate the indicator Raw Material Consumption (RMC), also referred to as Material Footprint (MF), by applying a global, multi-regional input-output (MRIO) model based on the GTAP database and extended by material extraction data. We examine world-wide patterns of material extraction and materials embodied in trade and consumption, investigating changes between 1997 and 2007. We find that flows of materials related to international trade have increased by almost 60% between 1997 and 2007. We show that the differences in Material Footprints per capita are huge, ranging from up to 100 tonnes in the rich, oil-exporting countries to values as low as 1.5 to 2 tonnes in some developing countries. We also quantify the differences between the indicators Domestic Material Consumption (DMC) and RMC, illustrating that net material exporters generally have a DMC larger than RMC, while the reverse is observed for net importers. Finally, we confirm the fact that most countries with stable or declining DMCs actually show increasing RMCs, indicating the occurrence of leakage effects, which are not fully captured by DMC. This challenges the world-wide use of DMC as a headline indicator for national material consumption and calls for the consideration of upstream material requirements of international trade flows.

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CERUTI, FRANCESCA. "Il settore estrattivo in Italia. Analisi e valutazione delle strategie competitive per lo sviluppo sostenibile". Doctoral thesis, Università degli Studi di Milano-Bicocca, 2013. http://hdl.handle.net/10281/41871.

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This thesis deals with the strategic management in a particular Italian industry: the mining sector. It is proposed an integrated methodology to implement a competitive analysis to explore trends in the mining sector in terms of business strategies adopted and strategic groups existent. The methodology uses secondary sources to make an environmental analysis and an accounting one. This second type makes use of key performance indicators of the sector as well as highlights the distribution of firms throughout the country. The research provides also information from a questionnaire about production, management, competitiveness, internationalization, innovation, recycling and environmental sustainability of enterprises behavior. Through PCA - Principal Component Analysis some positioning maps were created to identify strategic groups on the basis of four latent variables: competitive advantages, goals, tools and future investments. The design of research aims to bring out not only the Italian mining industry profile, but also to delineate its lineages and possible developments.

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Hanusa, Isabel. "Opportunities and Challenges for a B2B Trading Platform of Secondary Raw Material : An Exploratory Analysis based on the Sourcing Process of Sustainable SMEs in the Fashion and Textile Industry". Thesis, Högskolan i Borås, Akademin för textil, teknik och ekonomi, 2021. http://urn.kb.se/resolve?urn=urn:nbn:se:hb:diva-26382.

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Fashion and textile upcycling is currently considered a time-consuming and labour- intensive process. Since textile waste materials are not readily available as a secondary raw material, the process of sourcing pre- and post-consumer textile waste usually requires a lot of time and effort, and often results in a high inconsistency in input materials. In consequence, upcycling operations are generally difficult to scale up. In order to address this issue, this research study aims to explore the current sourcing process of secondary raw material as well as the opportunities and challenges this sourcing process implies for a B2B trading platform of secondary raw material. In order to serve the purpose of this research study, semi-structured interviews with experienced professionals from five small and medium-sized fashion and textile upcycling companies have been conducted. The empirical data collected through the semi-structured interviews was analysed using an inductive approach of qualitative content analysis. The overall findings suggest that concerning the sourcing process of post-consumer textiles for upcycling, the identified opportunities for a B2B trading platform outweigh the challenges. However, pre-consumer textile waste is often provided in the form of an already upcycled yarn from fabric or garment suppliers which gives the impression that a B2B trading platform is less relevant in this case. Nevertheless, the empirical results might have been impacted by the small sample size and the strong focus on post-consumer textiles. Therefore, more research is necessary in order to understand how SMEs working with pre-consumer textile waste source their input materials for upcycling and which opportunities and challenges this potentially different process implies for a B2B trading platform of secondary raw material.

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CAMPOS, REJANE D. de. "Influência da mercerização e irradiação por feixe de elétrons na aderência da fibra do ouriço da castanha do Brasil em matriz de polietileno de alta densidade". reponame:Repositório Institucional do IPEN, 2015. http://repositorio.ipen.br:8080/xmlui/handle/123456789/25303.

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Submitted by Claudinei Pracidelli (cpracide@ipen.br) on 2015-12-10T17:59:26Z No. of bitstreams: 0
Made available in DSpace on 2015-12-10T17:59:26Z (GMT). No. of bitstreams: 0
Tese (Doutorado em Tecnologia Nuclear)
IPEN/T
Instituto de Pesquisas Energeticas e Nucleares - IPEN-CNEN/SP

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15

Chang, Liang. "Sustainable Transformations of Methyl Coumalate : efficient Preparations of Unsaturated Carboxylic Acids, 2HPyrans, Trifluoromethyl Benzenes and Fluorescents Molecules". Thesis, Sorbonne université, 2018. http://www.theses.fr/2018SORUS109.

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Dans ce travail, nous décrivons le développement de nouvelles transformations utilisant le coumalate de méthyle, composé renouvelable biosourcé. Un couplage double séquentiel d'alkyl-alkyle ou d'alkyl-hydrure one-pot conduit à des acides insaturés d’intérêt. Nous décrivons une synthèse efficace de 2H-pyranes tétrasubstitués dans des conditions douces, puis nous décrivons une réaction efficace et sans solvant avec des dicétones trifluorométhylées, pour conduire à des benzènes trifluorométhylés. Enfin, nous avons rapporté une nouvelle stratégie générale de réaction de désaromatisation de composés hétérocycliques de type pyrido [1, 2-a] bicycliques
In this work, we have described the development of new transformations using bio-based renewable methyl coumalate as feedstock. An iron and copper catalyzed one-pot sequential double alkyl-alkyl or alkyl-hydride 1,6-addition with methyl coumalate was described. We then described an efficient synthesis of tetrasubstituted 2H-pyrans under mild condition. Later we reported a solvent-free reaction of methyl coumalate with trifluoromethyl-β-diketones, in a tBuOK-catalyzed domino sequence. A novel reaction, for efficient C-C bond formation between the bio-based methyl coumalate and a variety of imines and aldehydes via MBH pathway was reported. Finally, we reported a novel, general dearomatization strategy with an unprecedented pyrido[1, 2-a] fused heterocyclic scope

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Vašek, Tomáš. "Testování možností využívání druhotných surovin jako náhrady přírodních kameniv". Master's thesis, Vysoké učení technické v Brně. Fakulta stavební, 2014. http://www.nusl.cz/ntk/nusl-226736.

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Master's thesis consists of two parts, theoretical and practical. In the theoretical section are listed basic information about alternative aggregates used for concrete mixture, like polystyrene, cinder and recycled concrete. Further, the influence of these alternative aggregates, used as secondary raw materials, on the behaviour and properties of fresh respectively hardened concrete. Possibilities of application concrete containing secondary raw materials are mentioned. In the practical part are experimentally verified physical and mechanical properties of concrete containing crushed waste polystyrene beads, furthermore thermal insulation properties and resistance to elevated temperatures is tested. Influence of heating plant cinder powder as active addition to concrete mixture was tested. As a next is prepared concrete with replacement of coarse aggregate by cinder and recycled concrete and tested. The influence of these secondary raw materials on workability, compressive strength, frost resistance and water permeability of concrete is also defined. The last part of research is focused on recycled concrete such as main material used in mixture of aggregates bonded with cement, dispose for base layers in roads. In conclusion are discussed results from experimental research and summary of knowledge’s about using polystyrene, cinder and recycled concrete as aggregates for concrete mixtures.

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17

Wade, Richard Peter. "A systematics for interpreting past structures with possible cosmic references in Sub-Saharan Africa". Diss., Pretoria : [s.n.], 2009. http://upetd.up.ac.za/thesis/available/etd-05052009-174557/.

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18

Kinuthia, Wanyee. "“Accumulation by Dispossession” by the Global Extractive Industry: The Case of Canada". Thèse, Université d'Ottawa / University of Ottawa, 2013. http://hdl.handle.net/10393/30170.

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This thesis draws on David Harvey’s concept of “accumulation by dispossession” and an international political economy (IPE) approach centred on the institutional arrangements and power structures that privilege certain actors and values, in order to critique current capitalist practices of primitive accumulation by the global corporate extractive industry. The thesis examines how accumulation by dispossession by the global extractive industry is facilitated by the “free entry” or “free mining” principle. It does so by focusing on Canada as a leader in the global extractive industry and the spread of this country’s mining laws to other countries – in other words, the transnationalisation of norms in the global extractive industry – so as to maintain a consistent and familiar operating environment for Canadian extractive companies. The transnationalisation of norms is further promoted by key international institutions such as the World Bank, which is also the world’s largest development lender and also plays a key role in shaping the regulations that govern natural resource extraction. The thesis briefly investigates some Canadian examples of resource extraction projects, in order to demonstrate the weaknesses of Canadian mining laws, particularly the lack of protection of landowners’ rights under the free entry system and the subsequent need for “free, prior and informed consent” (FPIC). The thesis also considers some of the challenges to the adoption and implementation of the right to FPIC. These challenges include embedded institutional structures like the free entry mining system, international political economy (IPE) as shaped by international institutions and powerful corporations, as well as concerns regarding ‘local’ power structures or the legitimacy of representatives of communities affected by extractive projects. The thesis concludes that in order for Canada to be truly recognized as a leader in the global extractive industry, it must establish legal norms domestically to ensure that Canadian mining companies and residents can be held accountable when there is evidence of environmental and/or human rights violations associated with the activities of Canadian mining companies abroad. The thesis also concludes that Canada needs to address underlying structural issues such as the free entry mining system and implement FPIC, in order to curb “accumulation by dispossession” by the extractive industry, both domestically and abroad.

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Maghrebi, Ramin, David chiaramonti y Marco Buffi. "Hydroisomerization of waste lipids: improving the quality of biofuels and production of value added-chemicals". Doctoral thesis, 2021. http://hdl.handle.net/2158/1236516.

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This thesis is about conversion of the waste lipids into added-value products. In the first chapter, a comprehensive review explains the strength and weak points of the state-ot-the-art on the field and proposes various catalysts and effective parameters to improve the process. The next chapter explains the materials and method for the experimental parts. Subsequently, the following chapter includes the experimental steps and the results. The last chapter models a biodiesel plant based on the experimental results. Finally, the last chapter focuses on the conclusion of the entire study.

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20

Ma, Chuan-Tsung y 馬傳宗. "Sustainable Planning of the Bottom Ash been Produced by Li-Ze Incineration Plant in I-Lan County - Study for Substituting Part of Raw Materials by Bottom Ash in Portland Cement". Thesis, 2008. http://ndltd.ncl.edu.tw/handle/70555803740953113252.

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碩士
國立宜蘭大學
建築與永續規劃研究所碩士班
96
There are twenty-two incineration plants in Taiwan which are operating now, so garbage (Non-hazardous solid waste) treatment has been changed to incinerator from landfill. Li-Ze Incineration Plant in I-Lan County is one of them. It was operated by I-Lan County government since April 2006. Although Li-Ze Incineration Plant has release the pressure of waste treatment, but there is a problem that is ash residue treatment (include bottom ash and fly ash) must be solved immediately. Almost all of the bottom ash present still takes burying by the time been in I-Lan County. But the burial site volume is limited, and precious land resources. Ash residue is due to the use of sustainable treatment planning. The bottom ash accounted for 70% of ash residue. In this study, Li-Ze incinerator bottom ash at the end of the subject for the planning, will be transported to the cement plant in I-Lan County, as Portland cement alternative raw materials. Through the literature of factory certification is provided at the end of the I-Lan County slag handling specific recommendations can be developed for the national competent authority at the end of slag reuse policy for reference. The addition of Li-Ze incineration plant into the plant composition, composition and slag at the end of the end of the dissolution of Toxicity characteristic leaching procedure (TCLP) analysis, and send 1912.56 tons(20.79 tons/day) bottom ash to the cement plant, which resulted, Li-Ze incineration Plant at the end of slag cement major components of the composition. Li-Ze incineration plant in normal operation under the conditions of the plant in full at the end of slag (78 tons/day) as a cement substitute raw materials, the cement plant's quality of cement should be very minor, the other residue at the end of the pre-treatment, as appropriate later, the amount of bottom ash treatment in cement plant can be further increased.

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21

Singhal, Shrawan. "Jet and coat of adaptive sustainable thin films". 2012. http://hdl.handle.net/2152/22157.

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Deposition of nanoscale thickness films is ubiquitous in micro- and nano-scale device manufacturing. Current techniques such as spin-coating and chemical vapor deposition are designed to create only uniform thin films, and can be wasteful in material consumption. They lack the ability to adaptively prescribe desired film thickness profiles. This dissertation presents a novel inkjet-based zero-waste polymer deposition process referred to as Jet and Coat of Adaptive Sustainable Thin Films or J-CAST. The core of this process is built on an experimentally validated multi-scale fluid evolution model, based on extensions of lubrication theory. This model involves a nano-scale fluid film sandwiched between two flat plates: a compliant superstrate and a rigid substrate, with spatial topography on both surfaces. Accounting for the flexural elasticity of the compliant superstrate, and describing the temporal evolution of the fluid film in the presence of different boundary conditions reveals that instead of seeking process equilibrium, non-equilibrium transients should be exploited to guide film deposition. This forms the first core concept behind the process. This concept also enables robust full-wafer processes for creation of uniform films as well as nanoscale films with prescribed variation of thickness at mm-scale spatial wavelengths. The use of inkjets enables zero-waste adaptive material deposition with the preferred drop volumes and locations obtained from an inverse optimization formulation. This forms the second core concept behind the process. The optimization is based on the prescribed film thickness profile and typically involves >100,000 integer parameters. Using simplifying approximations for the same, three specific applications have been discussed - gradient surfaces in combinatorial materials science and research, elliptical profiles with ~10km radius of curvature for X-ray nanoscopy applications and polishing of starting wafer surfaces for mitigation of existing nanotopography. In addition, the potential of extending the demonstrated process to high throughput roll-roll systems has also been mentioned by modifying the model to incorporate the compliance of the substrate along with that of the superstrate.
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22

Ramesh, Rakul. "Finite element model-based code calibration for design of steel fibre reinforced recycled aggregate concrete beams". Thesis, 2019. http://hdl.handle.net/1959.7/uws:51885.

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As the construction industry is rapidly growing, the importance given to sustainable construction techniques has increased, to protect the environment and the limited reserves of natural resources. In order to reduce the negative environmental impact of the construction industry and to meet the increasing global demand for raw materials, the significance of recycling and reusing construction waste has increased over the years. Considering the wide applications of concrete and the large consumption of coarse aggregates used in concrete on a global scale, using Recycled Aggregate (RA) in concrete is an environment-friendly and sustainable construction alternative. However, Recycled Aggregate Concrete (RAC) does not exhibit adequate structural performance due to its inferior material properties compared to those of Natural Aggregate Concrete (NAC). At present, RAC is restricted to limited structural use and is extensively used only in pavements and as shotcrete in tunnels. Some previous studies have shown that RAC with adequate structural performance can be produced using various techniques. In this study, the particular technique of adding another material, Steel Fibre (SF), is investigated. SF improves the mechanical performance of RAC and makes it suitable for structural applications, especially under flexural load. This research aims to replace NAC with RAC that incorporates SF. The use of the new material, Steel Fibre Reinforced Recycled Aggregate Concrete (SFRRAC), in fabricating structural members subjected to flexure is proposed to gain advantages in terms of environmental effects, production costs and structural properties. Structural members fabricated using a new material such as SFRRAC should be designed according to proper design models and guidelines. The current design guidelines are limited to NAC and cannot be directly applied to SFRRAC due to the change in the material properties. This research proposes a design model for SFRRAC beam cross-sections under flexure, developed using a reliability based framework consisting of the following four parts: (i) a new theoretical model development for predicting the moment-capacities of SFRRAC beam cross-sections; (ii) experimental investigation of SFRRAC specimens at material-level and member level; (iii) numerical investigation on SFRRAC beams using Finite Element Analysis (FEA); and (iv) capacity factor calibration for a SFRRAC flexural capacity prediction model using the theoretical predictions and the adaptively combined database of experimental and FEA results.

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