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Tian, G. "Renewable materials from renewable resources." Thesis, University of York, 2015. http://etheses.whiterose.ac.uk/11187/.
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Renewable resources related to biomass, waste materials and recycled materials are an important concept in the principles of green chemistry, development of biorefineries and sustainability development. This thesis reports the repurposing of renewable resources which included wheat straw, biomass ash, waste cardboard (paper) and paper de-inking residues (DIR) to extract, synthesize and produce potentially high value chemicals, materials and composites. Biosilicate solutions were successfully extracted from biomass ash including wheat straw ash and miscanthus ash with aqueous potassium hydroxide solutions. Systematic analyses had been applied on the extraction of biosilicate solutions to obtain different types of silicate solutions for further applications of binder and mesoporous materials. Biosilicate solutions extracted from miscanthus ash were utilized as binders to make bioboards, whilst biosilicate solutions extracted from wheat straw ash were utilized as a silica resource to synthesize biobased mesoporous materials, namely bio-MCM-41 and bio-SBA-15. N2 porosimetry analysis revealed that mesoporous silica made from biosilicate solutions gave a surface area of bio-MCM-41 of >1000 m2 g-1 and a surface area of >800 m2 g-1 for bio-SBA-15. XRD, SEM and TEM analyses for both bio-MCM-41 and bio-SBA-15 revealed significant ordering pores, structure and the hexagonal arrays. Different kinds of renewable resources including wheat straw, pea pod waste and paper de-inking residue with the binder of biosilicate solutions and other chemical additives such as protein and starch were processed to bioboards. Also, wheat straw powder was added into cardboard/paper sheets to decrease the cost of paper manufacture and to improve mechanical properties. De-waxed wheat straw cardboard/paper sheets was successfully incorporated in to paper pulp to give a tensile index of 30-34 Nm/g similar with respect to conventional cardboard paper (tensile index of 30-32 Nm/g). A brief study to elicit sugars to the surface of cardboard/paper thus producing an in-situ sticky surface using low temperature microwave irradiation was conducted. Although it’s not conclusive, an aqueous fraction was expelled that contains organic matter (based on C-H stretch absorption bands noted in FT-IR), which may be due to sugars.
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Semenenko, E. "Non-renewable mineral resources." Thesis, Сумський державний університет, 2013. http://essuir.sumdu.edu.ua/handle/123456789/33826.
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Includes any ores or minerals that are being removed at or below the surface of the Earth, processed into a usable form, used, then burned for energy or placed in areas of disposal after use. Coal would typically begood example. Mineral resources are considered non-renewable because their production by earth forces on a geologic timescale cannot keep up with their consumption by humans on a human timescale.
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Williams, L. K. "Polyurethanes from renewable resources." Thesis, University of Sheffield, 2013. http://etheses.whiterose.ac.uk/4358/.
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A series of polyurethane (PU) and polyurethane-urea (PUU) elastomers derived from a renewable source have been synthesised and characterised extensively. Comparisons have been made to analogous series of elastomers utilising petroleum derived diisocyanates. The renewable elastomers utilised a difuranic diisocyanate (DFDI) derived from furfural, a readily available raw material synthesised from agricultural waste. DFDI was synthesised using a modified version of a published procedure, utilising triphosgene for the formation of the diisocyanate. The reaction kinetics of the diisocyanates used were compared using an adiabatic temperature rise technique in both catalysed and uncatalysed reactions, showing that DFDI reacts at approximately one fifteenth the rate of MDI with primary alcohols. The polyurethane series comprised MDI/DFDI and 1,4-butanediol (BD) hard segments (HS) and polytetrahydrofuran (PTHF) soft segments (SS) at 1, 2 and 2.9 kDa molecular weights. The PUU series utilised the 2kDa PTHF SS and the amine precursor to the diisocyanate, in effect simulating the HS produced in a water blown (polyurethane-urea) foam. In all PU elastomers the DFDI variants displayed much greater degrees of phase separation as evidenced by lower soft segment (SS) Tgs observed by both DSC and DMTA measurements, greater invariants observed in SAXS frames, more SS crystallinity observed in WAXS data and a much more clearly defined morphology observed in tapping mode AFM images. Crystallinity within the SS was found to be much higher in DFDI based elastomers, whereas crystalline hard segments were only observed in MDI based PU elastomers and was more pronounced at higher HS contents and at lower SS molecular weights. The PUU elastomers showed very clear morphologies in AFM images but were found to possess a lower degree of phase separation overall, agreeing with previous literature suggesting that the stronger hydrogen bonding of urea groups can hinder phase separation.
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Hai, Qu, Sun PiaoYi, and Li Xiang. "Waste disposal and renewable resources." Thesis, Högskolan Kristianstad, Sektionen för hälsa och samhälle, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:hkr:diva-10871.
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Purpose/aim: The purpose of this dissertation is to find out the effect of waste disposal on environment and to explore the effect of renewable resources on economy. We use some data to test and verify the existence of effects. Design/methodology/approach: We use our questionnaires to collect data, and analyze the data in statistical tests. We use case studies to find examples to verify the significance of waste classification and renewable resources as well as the problems in main cities of China. Findings: The analysis shows that we need to focus on waste classification education, if we want to apply it in real life. The best way to use renewable resource more widely is to aquire government support. If we can carry out waste classification better, we can make use of more renewable resources. Originality/value: The value of this paper is that we prove that using waste classification and renewable resource can increase economic growth rate and protect the environment. It is also important because economic growth brings about the reduction of environment quality. When the environment quality decreases, the economic level will also decrease.
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Davidsson, Simon. "Global energy transitions : Renewable energy technology and non-renewable resources." Licentiate thesis, Uppsala universitet, Naturresurser och hållbar utveckling, 2015. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-245307.
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The global energy system is dominated by the use of fossil fuels. This system suffers from several problems, such as different environmental issues, while the long-term energy security is sometimes questioned. As an alternative to this situation, a transition to a global energy system based on renewable energy technologies, to a large extent solar and wind energy, is commonly proposed. Constructing the technology needed for such a transition requires resources and how fast this could happen is somewhat disputed. This thesis explores methods to assess the potential constraints for realizing such a transition by looking at potential technology growth rates and outlooks of production of the required natural resources. The thesis is based on three papers presenting case studies that look at growth rates of wind energy as well as future production outlooks of lithium and phosphate rock. Using different types of growth patterns reaching proposed installed capacities of wind power, annual commissioning requirements are investigated, taking account for the limited life expectancy oftechnology. Potential outlooks of mineral production are explored using resource constrained curve-fitting models on global lithium production. A more disaggregated model looking at individual countries are used on phosphate rock production to investigate new perspectives on production outlooks. It is concluded that the growth rates of individual energy technologies affect the resource requirements and prospective constraints on energy transitions. Resource constrained modelling of resource production can provide spans of potential outlooks for future production of resources required for anenergy transition. A higher disaggregation of the modelling can provide new perspectives of potential constraints on future production. These aspects should be further investigated when proposing alternative future energy systems.
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Zakharova, Elena. "Sustainable plastics derived from renewable resources." Doctoral thesis, Universitat Politècnica de Catalunya, 2017. http://hdl.handle.net/10803/461889.
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In this century, the major use of synthetic polymers have been as replacements for more traditional materials, particulary in packaging. Today the packaging industry is by far the major user of plastics. Another interesting application of these materials is drug delivery systems. Polymers have played an integral role in the advancement of drug delivery technology by providing controlled release of therapeutic agents in constant doses over long periods, cyclic dosage and tunable release of both hydrophilic and hydrophobic drugs. Modern advances in drug delivery are now predicated upon the rational design of polymers tailored for specific cargo and engineered to exert distinct biological functions. Aliphatic polyesters such as poly(L-lactic acid), poly(butylene succinate), and polyhydroxyalkanoates among others, constitute primary examples of bio-based polymers that distinguish by being fully renewable and displaying partial or total biodegradability. This Ph.D. Thesis is devoted to the synthesis of aliphatic random and block polyesters from renewable resources with application for packaging and drug delivery. The main goal of this project is to develop new bio-based polymers with similar or even improved properties compared to those of conventional plastics obtained from non-renewable sources.
The two cyclic acetals, 2,3-di-O-methylene-L-threitol and dimethyl 2,3-di-O-methylene-L-threarate, were used for the synthesis of two series of PBS copolyesters differing in which unit, butylene or succinate, was replaced, in addition of the corresponding parent homopolyesters. 2,4:3,5-di-O-methylene-D-glucitol was used for the synthesis of PBS copolyesters by melt polycondensation. Three series of polyalkanoates (adipates, suberates and sebacates) were synthesized using as monomers three sugar-based bicyclic diols derived from D-glucose and D-mannose. ABA triblock copolyesters were synthesized by ROP of L-lactide in solution initiated by telechelic D-glucose- and L-tartaric-based polyester macroinitiators. The synthesized polyesters were characterized by nuclear magnetic resonance (NMR) spectroscopy, gel permeation chromatography (GPC) and viscosimetry. Thermal properties were analyzed by differential scanning calorimetry (DCS) and thermogravimetry (TGA). Crystalline structure of polyesters was studied by X-ray and its mechanical properties were evaluated as well. Hydrolytic degradation and biodegradation assays were followed by GPC and NMR. Nanoparticles made from triblock copolyesters were characterized by scanning electron microscopy (SEM) and dynamic light-scattering (DLS).<br>En este siglo, el mayor empleo que se les ha dado a los polímeros sintéticos ha sido como sustitutos de materiales más tradicionales, en particular, materiales para envase y embalaje. Hoy en día la industria de envasado es, por mucho, la mayor consumidora de plásticos. Otra aplicación interesante de estos materiales son los sistemas de administración de fármacos. Los polímeros han jugado un papel fundamental la tecnología de administración de fármacos al proporcionar un medio de liberación controlada de agentes terapéuticos en dosis constantes durante largos periodos; la dosificación cíclica y la liberación sintonizable de fármacos hidrofílicos e hidrofóbicos. Actualmente, los avances modernos en la administración de fármacos se basan en el diseño racional de polímeros para la liberación de dosis controladas que modifican distintas funciones biológicas de forma específica. Los poliésteres alifáticos tales como el poli(ácido L-láctico), el poli(succinato de butileno) y los polihidroxialcanoatos, entre otros, constituyen ejemplos primarios de polímeros de base biológica que se distinguen por ser completamente renovables y presentar biodegradabilidad parcial o total. Este trabajo de doctorado está dedicado a la síntesis de poliésteres alifáticos al azar y de bloques a partir de recursos renovables con aplicación para el envasado y la administración de fármacos. El objetivo principal de este proyecto es desarrollar nuevos polímeros biológicos con propiedades similares o incluso mejores en comparación a los plásticos convencionales obtenidos a partir de fuentes norenovables. Los dos acetales cíclicos, 2,3-di-O-metileno-L-treitol y dimetil 2,3-di-O-metileno-L-trearato, se usaron para la síntesis de dos series de copoliésteres de PBS que difieren en qué unidad, butileno o succinato, se reemplazó, además de los homopoliésteres originales correspondientes. Se usó 2,4:3,5-di-O-metileno-D-glucitol para la síntesis de copoliésteres de PBS mediante policondensación en estado fundido. Se sintetizaron tres series de polialcanoatos (adipatos, suberatos y sebacatos) usando como monómeros tres dioles bicíclicos base azúcar derivados de D-glucosa y D-manosa. Los copoliésteres tribloques ABA se sintetizaron mediante ROP de L-láctido en solución iniciada por macroiniciadores de poliester telequelico basados en D-glucosa y L-tartárico. Los poliésteres sintetizados se caracterizaron por espectroscopia de resonancia magnética nuclear (RMN), cromatografía de permeación en gel (GPC) y viscosimetría. Las propiedades térmicas se analizaron mediante calorimetría de barrido diferencial (DCS) y termogravimetría (TGA). La estructura cristalina de los poliésteres se estudió mediante rayos X y sus propiedades mecánicas también se evaluaron. La degradación hidrolítica y los ensayos de biodegradación fueron seguidos por GPC y NMR. Las nanopartículas hechas de copoliésteres tribloque se caracterizaron por microscopía electrónica de barrido (SEM) y dispersión de luz dinámica (DLS).
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Liu, Yan. "New biodegradable polymers from renewable resources." Doctoral thesis, KTH, Polymer Technology, 2000. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-2952.
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<p>High molecular weight poly(ester-carbonate)s have beenprepared by a two-step chain-extension reaction performed onoligomeric αω-bishydroxyl-terminatedpoly(1,3-propylene succinate).αω-Bishydroxyl-terminated copolymeric oligomers of1,3-propylene succinate/1,4-cyclohexanedimethylene succinatewere obtained by thermal polycondensation of1,3-propanediol/1,4-cyclohexanedimethanol/succinic acidmixtures having different composition, and subsequently chainextended using phosgene as coupling agent, which leads toaliphatic/alicyclic copoly(ester-carbonate)s. New highmolecular weight amphiphilic block copolymers ofpoly(ester-ether-carbonate), containing poly(1,3-propylenesuccinate) and poly(ethylene glycol) (PEG) segments in theirmain chain, were synthesized by a two-step chain-extensionreaction performed on a thermally-polycondensed α,ω-bishydroxyl-terminated oligomeric poly(1,3-propylenesuccinate) with PEG1000 and PEG2000, respectively. The newpolymers, besides having a biodegradable backbone, derive fromtwo monomers, 1,3-propanediol and succinic acid respectively,which can be obtained from renewable resources. Therefore, theyhave a potential as environmental friendly materials.</p><p>The molecular characterization by<sup>1</sup>H-NMR and IR spectroscopy, the molecular weight andmolecular weight distribution by SEC and the main thermalproperties by DSC of all synthesized materials are reported.Spectroscopic characterizations were in full agreement with theproposed structures. Thermal characterization demonstrated thatan increase in the cyclic ester unit content leads to anincrease in Tm and Tg of the copolymers. Solubility testsindicated that the introduction of hydrophilic PEG segmentsinto the high molecular weight polysuccinate imparts apparentamphiphilic character to the new materials. This is expected toinfluence even their biocompatibility and biodegradability.</p><p>The properties of aliphatic homopolyesters from renewablemonomers, 1,3-propanediol and succinic acid, were improved byintroducing aromatic urethane into the main chain of polymers,which gives place to the formation of strong hydrogen bondsamong the macromolecular chains of the material. Segmentedpolyester-urethanes (PEU) were synthesizedfromdi-hydroxyl-terminated poly(trimethylene succinate), chainextended with 4,4'-diisophenylmethane diisocyanate (MDI). Thematerials were characterized using SEC, DSC,<sup>1</sup>H-NMR,<sup>13</sup>C-NMR and INSTRON. The maximum weight averagemolecular weight approached 7.5× 10<sup>4</sup>. DSC detected the T<sub>g</sub>of the soft segment from10 to19° C and the T<sub>m</sub>of the hard segment from 175 to 210 ° C. Theaverage repeat number of hard segment ranges from 4.0 to 8.1,and the average repeat number of A<sub>n</sub>B<sub>m</sub>unit from 3.3 to 6.4. The average length of thehard segment decreases with increasing concentration ofpolyester in feeding.</p><p>The results clearly show that within the studied series theincrease in soft segment content reduced both crystallinity andmelting temperature of hard segment microcrystalline phase,which is accompanied by decrease in modulus due to weakerinteraction among polymer chains in microcrystalline phase. Thedegree of crystallinity, T<sub>g</sub>, T<sub>m</sub>, tensile strength, elongation, and Youngsmodulus were influenced by the ratio between hard and softsegment as well as the molecular weight of thepolyester-urethane. The introduction of the polyurethanesegments significantly reduces the degradability ofcorresponding aliphatic polyester, although there is stillenzymatic attack detectable during the enzymatic degradation.All samples exhibited significant weight losses after twomonths of compost simulation incubation. The highersoft-segment contents resulted in higher degradability. Weconcluded that the segmented polyester-urethane from1,3-propanediol and succinic acid is a promising, processable,soluble, and biodegradable thermoplastic elastomer.</p><p><b>Keywords:</b>polycondensation, block copolymer, chainextension, isocyanate, phosgene, dichloroformatecharacterization, biodegradation, renewable resources,1,3-propanediol, succinic acid, polyurethane, polyester,thermoplastic elastomer.</p>
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Jaros, Adam Marschall. "Four carbon oxychemicals from renewable resources." Licentiate thesis, Luleå tekniska universitet, Industriell miljö- och processteknik, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:ltu:diva-26727.
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Butanol, butyric acid and butyraldehyde are important 4-carbon oxychemicals typically generated from petro-chemical sources. All have significant markets in the food industry either for direct use as flavorings or as chemical feedstocks for generating butyric acid and butyraldehyde derived flavour compounds. Strong consumer sentiment against the consumption of petro-chemical derived products yields a demand for butyrate and butyraldehyde generated through all-natural methods. The bacterial fermentation production of butyric acid as well as bioconversion of butanol to butyraldehyde by yeast is presented in this work as a means of producing these products naturally. This thesis demonstrates the fermentation production of butyric acid with the Gram-positive anaerobic bacteria Clostridia tyrobutyricum. The organism consumes monomeric hexoses and pentoses to generate the carboxylic acids lactate, acetate and butyrate. The fermentations undertaken in this thesis were performed with either glucose or xylose as the primary carbon source in minimal media. Butyric acid studies were performed under anaerobic conditions as batch fermentations with lag, log and stationary phase growth being monitored by the optical density of the fermentation broth. Samples were drawn throughout the fermentations and HPLC analysis was performed to determine sugar consumption and butyric acid production over time. Another element expounded in this thesis is the potential use of the economical and renewable resource hot water extracted (HWE) hemicellose as a substrate for Clostridial fermentation. HWE hemicellose is produced as a waste stream from the pulp and paper industry and is converted to fermentable xylose with the concomitant release of acetic acid from the acetyl groups on the xylan backbone. With the presence of such a high concentration of acetic acid, microbial inhibition occurs and the productivity of xylose fermentation to butyric acid is diminished with the increased lag phase. C. tyrobutyricum xylose fermentation studies were performed with synthetic media challenging the fermentation with up to 26.3 g/L acetic acid to gain an understanding of the effects of acetic acid inhibition. Once the acetic acid induced lag phase growth was characterized this work was furthered by adapting a strain of C. tyrobutyricum to 26.3 g/L acetic acid conditions and demonstrating that this pre-adaptation could drastically reduce the acetic acid induced lag phase of a batch fermentation. From this set of studies, it is noted that the presence of acetic acid in the media increases carbon efficiency of the fermentation as during stationary growth C. tyrobutyricum re-uptakes free acetic acid from the environment and converts it into butyric acid. This thesis also demonstrates the bioconversion of butanol to butyraldehyde by the methylotrophic yeast Pichia pastoris. P. pastoris were grown to high cell densities under glycerol feed and then induced to produce the endogenous alcohol oxidase (AOX) enzyme by beginning the culture on methanol consumption after a short starvation period. AOX converts short chain aliphatic alcohols to the corresponding aldehyde with the utilization of oxygen. The AOX enzyme is inhibited by the final product butyraldehyde so studies were performed utilizing alternative amine based pH buffering systems which also aid the bioconversion by binding free butyraldehyde as a Schiff-base. By binding the butyraldehyde longer bioconversions were observed. For these conversions, AOX activity was monitored with an absorbance based enzyme assay and the butanol substrate and butyraldehyde product were determined by gas chromatography.<br>Godkänd; 2012; 20120906 (adajar); LICENTIATSEMINARIUM Examinator: Associate Professor Ulrika Rova, Institutionen för samhällsbyggnad och naturresurser, Luleå tekniska universitet Diskutant: Dr Christian Andersson, Formox AB, Perstorp Tid: Fredag den 12 oktober 2012 kl 10.00 Plats: C305, Luleå tekniska universitet
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Wojciechowski, Kristin Lynn. "Developing Platform Chemicals from Renewable Resources." Thesis, North Dakota State University, 2013. https://hdl.handle.net/10365/26852.
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The Department of Energy has listed 5-hydroxymethylfurfural (HMF) and 2,5-furandicarboxylic acid (FDCA) as two of the twelve building blocks derived from cellulosic biomass. HMF can serve as a renewable platform for the production of fuels and chemicals. Our research goal is to develop novel methods for the conversion of renewable resources to feedstock chemicals for polymer synthesis. The Diels-Alder reaction, the cycloaddition of alkenes and dienes, has become one of the most important synthetic methods used in organic chemistry. We were interested in carrying out Diels-Alder reactions with derivatives of HMF. Naphthalene analogs of terephthalic acid were synthesized by reacting HMF derivatives with benzyne which could lead to the formation of bio-based polyethylene terephthalate (PET) analogs.
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Hopkins, Mark. "Intelligent dispatch for distributed renewable resources." Thesis, Manhattan, Kan. : Kansas State University, 2009. http://hdl.handle.net/2097/1512.
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Mason, Pamela Jill. "Sustainable income and the depletion of renewable and non-renewable resources." Thesis, University of York, 1999. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.313842.
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McElroy, C. R. "Composite materials from copolymers incorporating renewable resources." Thesis, Keele University, 2008. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.491843.
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A robust method for the production of an emulsion polymer based on styrene-acrylic acid-acrylic ester was developed to give enhanced physical properties and/or reduced envhonmental impact. Replacing the methyl methacrylate content with n-butyl acrylate, tert-butyl acrylate and ethyl acrylate all gave stable polymer emulsions. Replacing methyl methacrylate with fatty acid based monomer containing no more than one polymerisable acrylate group per molecule also led to the production of a stable emulsion, with the fatty acid based monomer also acting as a self-emulsifying agent if having sufficient amphiphilic character. All stable emulsions were successfully used to produce composite materials.
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Stöven, Max Thilo [Verfasser]. "Demand for renewable resources / Max Thilo Stöven." Kiel : Universitätsbibliothek Kiel, 2014. http://d-nb.info/1052529364/34.
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Sullalti, Simone <1983>. "New eco-friendly polyesters from renewable resources." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amsdottorato.unibo.it/4627/1/sullalti_simone_tesi.pdf.
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Nowadays the development of sustainable polymers, with convenient properties to substitute the traditional petroleum-based materials, is one of the major issues for material science. The utilization of renewable resources as feedstock for biopolyesters is a challenging target.The research work described in the present thesis is strictly connected to these urgent necessities and is focused mainly in finding new biopolymers, in particular biopolyesters, which are obtainable from biomass and characterized by a wide range of properties, in order to potentially substitute polyolefins and aromatic polyesters (for example, poly(ethylene terephthalate))
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Sullalti, Simone <1983>. "New eco-friendly polyesters from renewable resources." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2012. http://amsdottorato.unibo.it/4627/.
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Nowadays the development of sustainable polymers, with convenient properties to substitute the traditional petroleum-based materials, is one of the major issues for material science. The utilization of renewable resources as feedstock for biopolyesters is a challenging target.The research work described in the present thesis is strictly connected to these urgent necessities and is focused mainly in finding new biopolymers, in particular biopolyesters, which are obtainable from biomass and characterized by a wide range of properties, in order to potentially substitute polyolefins and aromatic polyesters (for example, poly(ethylene terephthalate))
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Orozco, Corredor Camilo <1984>. "Scheduling of Resources in Renewable Energy Communities." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2021. http://amsdottorato.unibo.it/9648/1/Orozco_Corredor_Camilo_tesi.pdf.
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This work presents a detailed study of the scheduling of power and energy resources in renewable energy communities (RECs). The study has been developed starting from the analysis of a single basic unit of the community, i.e., the prosumer and its microgrid, to the scheduling and expansion of the energy community concept with several prosumers through several scenarios.
The individual scheduling problem of the prosumer has been studied as a day-ahead deterministic problem and as a multistage stochastic problem to consider uncertainties associated with energy generation and energy consumption. Furthermore, an approach has been formulated to consider the integration of bidirectional charging services of electrical vehicles within a local energy system with the presence of renewable generation.
Moreover, this thesis focuses on the scenario in which direct energy transactions between prosumers located within a REC are allowed in addition to the energy transactions with the external energy provider. The day-ahead scheduling problem has been addressed by a centralized approach and by a distributed approach based on the alternating direction method of multipliers (ADMM). The developed approaches provide the scheduling of the available energy resources to limit the balancing action of the external grid and allocate the internal network losses to the corresponding energy transactions.
Finally, the thesis presents a coordinated day-ahead and intra-day approach to provide the optimal scheduling of the resources in a REC. In this case, the ADMM-based procedure, which is aimed at minimizing the total energy procurement costs, is adapted to cope with the impact of the fluctuation of both the local energy generation and demand during the day. To achieve this, a day-ahead multistage stochastic optimization approach is combined with an intra-day decision-making procedure, able to adjust the scheduling of the energy resources according to the current operational conditions.
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Kaulgud, R. A. "Sucrose esters as surfactants from renewable resources." Thesis(M.Sc.), CSIR-National Chemical Laboratory, Pune, 1991. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/1962.
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Pandey, J. K. "Degradability of polymer composites from renewable resources." Thesis(Ph.D.), CSIR-National Chemical Laboratory, Pune, 2004. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/2425.
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Martino, Lucrezia <1985>. "Structure-property relations in polymers from renewable resources." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amsdottorato.unibo.it/6484/1/Martino_Lucrezia_TESI.pdf.
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The present research project focuses its attention on the study of structure-property relations in polymers from renewable sources (bio-based polymers) such as polymers microbially produced, i.e. polyhydrohyalkanoates (PHAs) or chemically synthesized using monomers from renewable sources, i.e. polyammide 11 (PA11). By means of a broad spectrum of experimental techniques, the influence of different modifications on bio-based polymers such as blending with other components, copolymerization with different co-monomers and introduction of branching to yield complex architectures have been investigated.
The present work on PHAs focused on the study of the dependence of polymer properties on both the fermentation process conditions (e.g. bacterial strain and carbon substrate used) and the method adopted to recover PHAs from cells. Furthermore, a solvent-free method using an enzyme and chemicals in an aqueous medium, was developed in order to recover PHAs from cells. Such a method allowed to recover PHA granules in their amorphous state, i.e. in native form useful for specific applications (e.g. paper coating).
In addition, a commercial PHA was used as polymeric matrix to develop biodegradable and bio-based composites for food packaging applications. Biodegradable, non-toxic, food contact plasticizers and low cost, widely available lignocellulosic fibers (wheat straw fibers) were incorporated in such a polymeric matrix, in order to decrease PHA brittleness and the polymer cost, respectively.
As concerns the study of polyamide 11, both the rheological and the solid-state behavior of PA11 star samples with different arm number and length was studied. Introduction of arms in a polymer molecule allows to modulate melt viscosity behavior which is advantageous for industrial applications. Also, several important solid-state properties, in particular mechanical properties, are affected by the presence of branching.
Given the importance of using ‘green’ synthetic strategies in polymer chemistry, novel poly(-amino esters), synthesized via enzymatic-catalyzed polymerization, have also been investigated in this work.
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Martino, Lucrezia <1985>. "Structure-property relations in polymers from renewable resources." Doctoral thesis, Alma Mater Studiorum - Università di Bologna, 2014. http://amsdottorato.unibo.it/6484/.
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The present research project focuses its attention on the study of structure-property relations in polymers from renewable sources (bio-based polymers) such as polymers microbially produced, i.e. polyhydrohyalkanoates (PHAs) or chemically synthesized using monomers from renewable sources, i.e. polyammide 11 (PA11). By means of a broad spectrum of experimental techniques, the influence of different modifications on bio-based polymers such as blending with other components, copolymerization with different co-monomers and introduction of branching to yield complex architectures have been investigated.
The present work on PHAs focused on the study of the dependence of polymer properties on both the fermentation process conditions (e.g. bacterial strain and carbon substrate used) and the method adopted to recover PHAs from cells. Furthermore, a solvent-free method using an enzyme and chemicals in an aqueous medium, was developed in order to recover PHAs from cells. Such a method allowed to recover PHA granules in their amorphous state, i.e. in native form useful for specific applications (e.g. paper coating).
In addition, a commercial PHA was used as polymeric matrix to develop biodegradable and bio-based composites for food packaging applications. Biodegradable, non-toxic, food contact plasticizers and low cost, widely available lignocellulosic fibers (wheat straw fibers) were incorporated in such a polymeric matrix, in order to decrease PHA brittleness and the polymer cost, respectively.
As concerns the study of polyamide 11, both the rheological and the solid-state behavior of PA11 star samples with different arm number and length was studied. Introduction of arms in a polymer molecule allows to modulate melt viscosity behavior which is advantageous for industrial applications. Also, several important solid-state properties, in particular mechanical properties, are affected by the presence of branching.
Given the importance of using ‘green’ synthetic strategies in polymer chemistry, novel poly(-amino esters), synthesized via enzymatic-catalyzed polymerization, have also been investigated in this work.
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Hennlock, Magnus. "On strategic incentives and the management of stochastic renewable resources /." Uppsala : Dept. of Economics, Swedish University of Agricultural Sciences, 2005. http://epsilon.slu.se/2005124.pdf.
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Elíasson, Lúðvík. "Economic growth with a renewable resource sector /." Thesis, Connect to this title online; UW restricted, 2001. http://hdl.handle.net/1773/7378.
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Hameedi, Ayoub. "Addressing the Electricity Shortfall in Pakistan through Renewable resources." Thesis, Uppsala universitet, Institutionen för geovetenskaper, 2012. http://urn.kb.se/resolve?urn=urn:nbn:se:uu:diva-188697.
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This report focuses on addressing the electricity shortfall in Pakistan with the help of renewable resources. At present, the country is facing a shortfall of almost 7,000 megawatts (MW) which is affecting every walk of life and causing almost 1.5 to 2% GDP loss on annual basis. Previous research done on this subject reveals that electricity demand has always remained high then the total generation capacity of Pakistan. Similarly, it has been pointed out that the country is not taking maximum benefit from its available hydro, solar and wind resources. This leads us to the basic purpose of this research which is to have an exploratory understanding of the strategies adopted by India, China, Brazil and Spain for electricity generation in a green fashion and how can these strategies be implemented in Pakistan. Case study has been adopted as methodology for this purpose. This research work also discusses the factors contributing in the lack of promotion of renewable energy resources in Pakistan and provide detailed analyses of positive changes these projects can bring in lives of masses in Pakistan. The sustainable management of surface water resource in the country has been discussed in particular as the country faced worst floods in its history during years 2010 & 2011. It will result in enhancing the surface water storage ability of Pakistan which will significantly reduce our dependence on underground water reserves and will directly increase our electricity generation capacity through hydro dams. Similarly, sustainable forest management has been discussed at length as it will not only ensure environmental sustainability but will also result in increase availability of biomass. Not to mention the fact that wood biomass is much cheaper then conventional source of electricity generation provided it is obtained through sustainable forest management. Finally, if all the green strategies discussed in this research work will be implemented, it will increase the overall electricity generation capacity of Pakistan up to 9% respectively.
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Ogunjobi, Joseph K. "Generation of novel polymers and surfactants from renewable resources." Thesis, University of York, 2016. http://etheses.whiterose.ac.uk/13556/.
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This research study aimed at using renewable resources from biomass to generate novel polymers and surfactants for applications in Home and Personal Care products. Esterification, transesterification, epoxidation and ring opening reactions were applied with the instrumentality of clean synthetic techniques to deliver over sixty nonionic surfactants with main hydrophilic head containing 9-34 units of ethylene oxide (EO) and hydrophobic tail containing C19-28 hydrocarbons from oleate derivatives, epoxidised linseed oil and sophorolipid. The surfactants were fully characterised with nuclear magnetic resonance spectroscopy, super-critical fluid chromatography, differential scanning calorimetry, electrospray ionisation-mass spectrometry and infrared spectroscopy. Surfactants properties were assessed based on physicochemical measurements and hydrophilic-lipophilic balance. The synthesised polymeric surfactants have great potential applications ranging from oil-in water emulsification, wetting and spreading, detergency and to solubilisation purposes, and can be incorporated into Home and Personal Care products. Alongside the above study, attempts were made to convert 2,5-furan dicarboxylic acid to diethyl terephthalate as a step to making 100% bio-based poly(ethylene terephthalate), and vital plastic packaging for Home and Personal Care formulations. The bio-based aromatic monomer was synthesised via Diels-Alder addition of diester of the furan to ethene under a solventless system catalysed by in-expensive heterogeneous Lewis acid catalysts. DET yield up to 59% was obtained, this being a substantial improvement compared to yields for the same or similar reaction of FDCA and its esters reported elsewhere. The synthetic route herein described was compared with other published biomass routes to bio-based PET using green chemistry metric toolkits, and ours stands as the preferred biomass route based on this comprehensive assessment.
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Morin, Chassé Rémi. "Multiple extraction strategies in markets with non-renewable resources." Thesis, Université Laval, 2011. http://www.theses.ulaval.ca/2011/28824/28824.pdf.
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Jenkins, Rhodri. "Renewable liquid transport fuels from microbes and waste resources." Thesis, University of Bath, 2015. https://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.655722.
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In order to satisfy the global requirement for transport fuel sustainably, renewable liquid biofuels must be developed. Currently, two biofuels dominate the market; bioethanol for spark ignition and biodiesel for compression ignition engines. However, both fuels exhibit technical issues such as low energy density, poor low temperature performance and poor stability. In addition, bioethanol and biodiesel sourced from first generation feedstocks use arable land in competition with food production, and can only meet a fraction of the current demand. To address these issues it is vital that biofuels be developed from truly sustainable sources, such as lignocellulosic waste resources, and possess improved physical properties. To improve and control the physical properties of a fuel for specific application, one must be able to tailor the products formed in its production process. All studies within this thesis, therefore, have the aim of assessing the fuels produced for their variability in physical property, or the aim of directing the process considered to specific fuel molecules. In Chapter 2, spent coffee grounds from a range of geographical locations, bean types and brewing processes were assessed as a potential feedstock for biodiesel production. While the lipid yield was comparable to that of conventional biodiesel sources, the fatty acid profile remained constant irrespective of the coffee source. Despite this lack of variation, the fuel properties varied widely, presumably due to a range of alternative biomolecules present in the lipid. Though coffee biodiesel was produced from a waste product, the fuel properties were found to be akin to palm oil biodiesel, with a high viscosity and pour point. The blend level would therefore be restricted. In Chapter 3 the coffee lipid, as well as a range of microbial oils potentially derived from renewable sources were transformed into a novel aviation and road transport fuel through cross-metathesis with ethene. Hoveyda-Grubbs 2nd generation catalyst was found to be the most suitable, achieving 41% terminal bond selectivity under optimum conditions. Metathesis yielded three fractions: an alkene hydrocarbon fraction suitable for aviation, a shorter chain triglyceride fraction that upon transesterification produced a short chain biodiesel fuel, and a multifunctional volatile alkene fraction that could potentially have application in the polymer industry. Though there was variation for the road transport fuel fraction due to the presence of long chain saturates, the compounds fell within the US standard for biodiesel. The aviation fraction lowered the viscosity, increased the energy density, and remained soluble with Jet A-1 down to the required freezing point. Oleaginous organisms generally only produce a maximum of 40% lipid, leaving a large portion of fermentable biomass. In Chapter 4, a variety of ethyl and butyl esters of organic acids – potentially obtainable from fermentation – were assessed for their suitability as fuels in comparison to bioethanol. One product, butyl butyrate, was deemed suitable as a Jet A-1 replacement while four products, diethyl succinate, dibutyl succinate, dibutyl fumarate and dibutyl malonate, were considered as potential blending agents for diesel. Diethyl succinate, being the most economically viable of the four, was chosen for an on-engine test using a 20 vol% blend of DES (DES 20) on a chassis dynamometer under pseudo-steady state conditions. DES20 was found to cause an increase in fuel demand and NOx emissions, and a decrease in exhaust temperature, wheel force, and CO emissions. While fermentation is generally directed to one product, producing unimolecular fuels, they do not convert the entirety of the biomass available. An alternative chemical transformation is pyrolysis. In Chapter 5, zeolite-catalysed fast pyrolysis of a model compound representative of the ketonic portion of biomass pyrolysis vapour – mesityl oxide – was carried out. The aim of this study was to understand the mechanistic changes that occur, which could lead to improved bio-oil yields and more directed fuel properties of the pyrolysis oil. While HZSM-5 and Cu ZSM-5 showed no activity for hydrogenation and little activity for oligomerisation, Pd ZSM-5 led to near-complete selective hydrogenation of mesityl oxide to methyl isobutyl ketone, though this reduced at higher temperatures. At lower temperature (150-250 °C), a small amount of useful oligomerisation was observed, which could potentially lead to a selective pyrolysis oligomerisation reaction pathway.
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Dragović, Njegoš, and Snežana Urošević. "Using a renewable energy resources in the clothing industry." Thesis, Київський національний університет технологій та дизайну, 2021. https://er.knutd.edu.ua/handle/123456789/19082.
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The clothing industry is one of the most affected branches of the economy in crisis conditions such as the global Covid-19. If the production of textiles took place in the existing conditions, many companies would stop because the labor costs are high. From the processing of raw materials, through the production of textiles, all the way to the production of clothing, the greatest chance to return to real trends is the energy transition, technological transfer and adjustment of workers. The aim of this paper is to point out the possibilities that would keep the textile industry in line with global trends in the use of renewable energy sources.
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Dam, My. "Essays on ambiguity and optimal growth with renewable resources." Thesis, université Paris-Saclay, 2020. http://www.theses.fr/2020UPASE011.
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Dans le deux premiers chapitres, nous étudions le problème du contrat optimal en présence de risque et de l'ambiguïté dans le cadre d'un problème du contrôle optimal. L'ambiguïté est modélisés selon Klibanoff et al. (2005). Notre approche généralise les analyses effectuées jusqu'à présent en considérant le contrat d'assurance comme la paire d'une prime et une fonction d'indemnisation à résoudre simultanément. Nous prouvons l'existence d'un contrat optimal dans le cas le plus général où tous les agents peuvent être simultanément averses à l'ambiguïté et au risque, ce qui englobe tous les cas précédemment examinés. Nous caractérisons non seulement le partage du risque mais aussi la règle du partage de l'ambiguïté entre les parties contractantes. Dans le cas de l'aversion vers l'ambiguïté unilatérale, nous montrons qu'une politique de franchise directe ne peut pas constituer un contrat d'assurance optimal. Au contraire, sous l'hypothèse que les densités conditionnelles puissent être classées selon le rapport de vraisemblance monotone, un contrat avec des franchises qui disparaissent est optimal, un résultat qui est cohérent avec Gollier (2014). En particulier, la méthodologie mise en œuvre complète l'analyse de Raviv (1979) pour le cas du risque pur avec un assureur neutre au risque, montrant qu'une couverture de limite supérieure ne peut pas constituer un optimum. Ce résultat est robuste à la neutralité de l'ambiguïté.Dans le troisième chapitre, j'ai examiné l'impact du risque et de l'ambiguïté sur l'investissement optimal dans le capital humain et le capital physique en utilisant le modèle de Ben-Porath (1967) à deux périodes. L'incertitude (à la fois dans le sens du risque et de l'ambiguïté) est introduite à l'accumulation de capital humain de deux façons. Lorsque l'incertitude porte sur le taux de dépréciation du capital humain (obsolescence incertaine des compétences), j'ai constaté que l'investissement optimal dans le capital humain augmente toujours, que soit présent ou non le capital physique. Cette réponse à l'incertitude d'un ménage représente le comportement typique de l'auto-assurance. En revanche, lorsque l'incertitude se porte sur l'efficacité de l'accumulation du capital humain, l'investissement optimal dans le capital humain diminue parmi les ménages avec l'aversion au risque relative constante inférieure à un. Cette réponse à l'incertitude est typique d'un ménage qui considère l'investissement comme un actif à rendement risqué au lieu d'une assurance.Le dernier chapitre (relativement indépendant des chapitres précédents) examine une question importante dans la théorie de la croissance: le rôle des ressources renouvelables et des externalités dans l'économie. L'introduction d'une fonction régénératrice (d'une ressource naturelle) non-concave par rapport à l'un des arguments rend le problème non convexe. En conséquence, nous ne pouvons plus utiliser les techniques traditionnelles de programmation dynamique. En attaquant ce probpème, nous proposons une nouvelle méthode pour étudier une économie à deux secteurs en présence des externalités. En l'occurrence, nous introduisons le concept de "gain net de stock", qui est une notion similaire au "gain net d'investissement" introduit par Kamihigashi et al. (2007). En absence des propriétés convexes ou supermodulaires habituelles, nous prouvons que l'économie évolue pour augmenter le gain net de stock et établissons les conditions assurant la convergence de l'économie à long terme. Cette approche peut être appliquée aux problèmes similaires précédemment posées, ou être étendu à l'analyse des économies multisectorielles en général<br>In the first two chapters, we study the optimal contract problem in presence of risk and ambiguity as an optimal control problem. Ambiguity is modeled according to Klibanoff et al. (2005). Our approach generalizes all the analyses caried out so far by considering the insurance contract as a pair of an indemnity function and a premium to be solved for simultaneously. We prove the existence of an optimal contract in the most general case, allowing for the principal or the insurance to be averse or neutral to risk or ambiguity. We characterize both the risk and ambiguity sharing rule between the contracting parties. In the case of one-sided ambiguity aversion, we show that an optimal insurance contract cannot contain a straight deductible policy. Furthermore, under the hypothesis that the conditional densities can be ranked according to the monotone likelihood ratio, we prove that a disappearing deductible contract is optimal, a result that is consistent with Gollier (2014). In particular, our method completes the analysis of Raviv (1979), showing that in the pure risk case with a risk-neutral insurer, a policy with an upper limit coverage cannot be optimal. This result also holds under ambiguity neutrality.In the third chapter, I examine the impact of risk and ambiguity on the optimal investment in human and physical capital in a two-period Ben-Porath (1967)'s model. Uncertainty (both in the form of risk and ambiguity) is introduced to the accumulation of human capital via two channels. When uncertainty is on the depreciation rate of human capital (uncertain obsolescence of skills), I have found that the optimal investment in human capital always increases, whether or not physical capital is present. This response to uncertainty of an optimizing household represents the typical self-insurance behavior. By contrast, when uncertainty is on the effectiveness of human capital accumulation, the optimal investment in human capital diminishes among the households with a degree of constant risk aversion less than one. This response to uncertainty is typical of a household who views human capital as an investment with risky/ambiguous return.The final chapter (relatively independent from the preceding chapters) examines an important subject in the theory of economic growth: the role of renewable resources and externalities in the economy. The introduction of a (natural resource) regenerating function that is non-concave with respect to one of its arguments renders the problem non-convex. In consequence, we can no longer apply traditional dynamic programming techniques to this model. We thus propose a new method to study two-sector economies with externalities. In particular, we introduce the notion of "the net gain of stock", which is a notion similar to "the net gain of investment" of Kamihigashi et al. (2007). In absence of the usual convex and supermodular requirements, we prove that the economy evolves to increase the net gain of stock, and establish conditions that ensure long-run convergence. This approach can be adapted to similar problems previously studied, or be extended to the analysis of multi-sector economies in general
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Anríquez, Nilson Gustavo Adolfo. "Renewable resources as a factor of production in international trade." College Park, Md. : University of Maryland, 2005. http://hdl.handle.net/1903/3089.
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Thesis (Ph. D.) -- University of Maryland, College Park, 2005.<br>Thesis research directed by: Agricultural and Resource Economics. Title from t.p. of PDF. Includes bibliographical references. Published by UMI Dissertation Services, Ann Arbor, Mich. Also available in paper.
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Clarke, Andrew Donald. "Steps toward a net-zero campus with renewable energy resources." Thesis, Clemson University, 2015. http://pqdtopen.proquest.com/#viewpdf?dispub=3680669.
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<p> With the increasing attention and support behind plug in hybrid electric vehicles, research must be conducted to examine the impacts of vehicles on electric distribution and transmission systems. This research aims first to model the behavior of vehicle battery chargers during system disturbances and mitigate any impacts. A distribution test system example is modeled and several different vehicle charger topologies are added. Faults are applied to the distribution system with vehicle chargers connected and the results are examined. Based on these results, a control strategy to mitigate their negative impacts is suggested. Photovoltaic panels are then added to the system and the study is repeated. </p><p> Several services that plug in hybrid electric vehicles are capable of providing to the electric system are presented in order to allow electric vehicles to be seen as an asset to electric systems rather than a burden. These services are particularly focused on an electric system such as might be found on a college campus, which in this case is represented by the Clemson University electric distribution system. The first service presented is dynamic phase balancing of a distribution system using vehicle charging. Distribution systems typically face problems with unbalance. At most large car parks, a three phase electric supply is expected even though current standardized chargers are single phase. By monitoring system unbalance and choosing which phase a vehicle is allowed to charge from, unbalance between phases is reduced in a distribution system. The second service presented is a decentralized vehicle to campus control algorithm based on time of use rates. Using time of use electricity prices, discharging vehicle batteries during high prices and recharging at low prices is explored. Battery degradation as well as limits placed by required vehicle range availability are included in the decision on whether to charge or discharge. Electric utilities will also benefit from a reduction of load at peak times if vehicles discharge back to the campus. A comparison with stationary battery energy storage is included.</p>
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Rühlicke, Stefanie [Verfasser]. "Saccharides as renewable resources for novel functional materials / Stefanie Rühlicke." Göttingen : Niedersächsische Staats- und Universitätsbibliothek Göttingen, 2021. http://d-nb.info/1225556015/34.
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Jalkenäs, Frida, and Monika Mizgalewicz. "Modelling resources to supply Ethiopia with renewable electricity by 2030." Thesis, KTH, Industriell ekologi, 2017. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-213925.
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Energy is a crucial factor when it comes to development. Among other electricity is important when advancing the living standards of a society as it facilitates various actions and mechanisms. Through the past years social trends such as increased population have put energy and electricity systems under stress as they have often been based on limited and unsustainable fossil fuels. A need for a shift from the conventional fuels to renewable sources becomes more prominent and development needs to be performed in a sustainable way. Ethiopia is one of the countries who have expressed a desire to reach sustainable development by adapting United Nations’ Sustainable Development Goals. This project focuses and analyzes more specifically Ethiopia’s relation to, and possibility of reaching Goal 7 - sustainable energy for all. It attempts to find a future configuration of energy sources which will create an electricity system which will benefit the economy, the social aspect and the environment. The aim is to have a cost-efficient energy mix which supplies all of Ethiopia’s inhabitants with electricity without having to contribute with any carbon dioxide emissions. A literature review is performed to obtain country specific information such as geographical predispositions, and a field trip to Addis Ababa is conducted where data regarding the electricity system is collected. Modelling is then carried through by usage of tools MoManI and OnSSET and the obtained results show a continuous trend in all scenarios where solar and wind compromise the biggest part of electricity production in 2030 and after. Every scenario also allows all inhabitants access to electricity by year 2030. Further, four out of five scenarios ensures elimination of carbon dioxide emissions by 2022, and all five by 2030.
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Nasser, M. H. "Evaluation and management of renewable land resources in NE Iraq." Thesis, SOAS, University of London, 1986. http://eprints.soas.ac.uk/28473/.
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In the north-east region of Iraq, special physical and institutional conditions have governed the use of the land resources. Both the physical environment and the socioeconomic structures have imposed great constraints on the management of agriculture and the land resources. The uneven terrain of the majority of the region is responsible for the generally poor soil conditions and substandard farm operations. Political instability, low management skills and depressed rural income have further inhibited enterprise and hindered improvement and conservation of the environment. In choosing a method for evaluating the land resources for rainfed agriculture and grazing, the FAO approach was selected. Fundamental to this approach is that a value (suitability class) given to a land unit is relevant only in relation to a clearly defined use. In view of the scarcity of data, difficulties associated with field verification and lack of detailed background surveys, broad (reconnaissance) inventories of the resources have been prepared, permitting the selection of possible future areas of development and of management priorities. In this method, the land resources have been appraised on an essentially qualitative basis, and economic analysis was carried out in general terras. Affected by erratic and sometimes insufficient rainfall, the agricultural lands of the region are largely under an extensive and traditional mode of rainfed agriculture. Driven primarily by considerations of survival, inputs in agriculture are minimised, and pressures for self- sufficiency have jeopardised chances of obtaining a high level of marketable surplus. Equally constrained are the region's grazing activities. In the absence of controls on utilisation, firm tenure and modern technology, the vegetation and soil fertility have progressively deteriorated, while farmers continue to increase their stocks to meet demand for livestock products in excess of available pasture. The study concludes with a commentary on the management options for the region, with a view to achieving a better standard of utilisation of the renewable land resources for the two major agricultural sectors in the north-east region, rainfed agriculture and grazing.
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Mathis, Mitchell Lee. "Policy design in an imperfect world : essays on the management and use of open access renewable natural resources /." Digital version accessible at:, 1999. http://wwwlib.umi.com/cr/utexas/main.
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Kondratyuk, O. V. "Renewable energy sources in Ukraine." Thesis, Видавництво СумДУ, 2009. http://essuir.sumdu.edu.ua/handle/123456789/13612.
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Sheehan, Michele. "PERSPECTIVES/VISIONS/ACTIONS IN LANDSCAPE DECISION-MAKING." Diss., The University of Arizona, 1994. http://hdl.handle.net/10150/187563.
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The Perspectives/Visions/Actions framework is designed to facilitate deeper understanding of issues and broader inclusion of
publics in landscape decision-making conversations. A parallel analysis of landscape and policy theory was used to constructed the framework. Common terminology and visual expression of spatial/temporal aspects of landscape are viewed through the interactive segments of Perspectives, Visions, and Actions. Perspectives described through landscape/human relationships and intuitive images of landscape provide insight into various viewpoints. Visions, visual landscape features described in landscape ecology terminology, provide a base for development of potential scenarios. Actions, Tools and Rules, relate viewpoints and scenarios to a range of choices for implementing change. Document content analysis, open-ended interviews, and systematic establishment of a transect baseline from aerial photographs were used to historically analyze three shoreline landscapes (Indiana Dunes National Lakeshore, Cape Cod and Point Reyes National Seashores) through framework language and schematic. Landscape information, viewpoints, and choices within the case study landscapes were uniquely illustrated. Perspectives groupings of intuitive images indicated ovelapping viewpoints and set an inclusive base for landscape information types. Visions landscape ecology language used both to construct the schematic and to translate information into comron expressions provided a base for issue discussion. Actions tools and rules data provided examples of implementation choices which related to the Perspectives and Visions.
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Edwards, Taylor. "Desert tortoise conservation genetics." Thesis, The University of Arizona, 2003. http://hdl.handle.net/10150/291566.
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Managing for the long-term survival of a species requires an understanding of its population genetics. The desert tortoise, Gopherus agassizii, inhabits the Mojave and Sonoran deserts of North America. Desert tortoises face many threats to their continued survival, including habitat loss and fragmentation. I used mitochondrial and microsatellite DNA markers to examine genetic structure within and among populations of desert tortoises. I found that both the Mojave and Sonoran populations of desert tortoise exhibit similar patterns of population genetic structure. Gene flow among localities within each region is part of the evolutionary history of the desert tortoise and dispersal events probably play an important role in the long-term maintenance of populations. Movement barriers caused by anthropogenic landscape changes have the potential to effect desert tortoise population viability. Understanding the historical connectivity between and within the Mojave and Sonoran populations of desert tortoises will help facilitate the conservation of this species.
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Claudino, Mauro. "Macromolecular design : UV-curable thiol-ene networks based on renewable resources." Doctoral thesis, KTH, Ytbehandlingsteknik, 2013. http://urn.kb.se/resolve?urn=urn:nbn:se:kth:diva-129549.
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Plant oils and terpenes are ubiquitous natural renewable compounds. The double bonds contained in most of these monomers can be utilized via the photo-induced free-radical thiol–ene reaction to create novel bio-derived polymer thermosets representing a valuable ‘green’ alternative to petrochemical olefins and resulting synthetic plastic materials. Nevertheless, there are several factors limiting their applicability, the first one being the relatively slow reaction rates towards thiol–ene coupling and many times the need to modify these natural olefins to make them more reactive. The latter process necessarily introduces additional pre-synthesis steps which has implications related both to cost and synthetic routes employed thereafter, those of which may or may not follow the principles of Green Chemistry. Therefore, this thesis intends to gain primary insight about the thiol–ene mechanism, kinetics and reactivity involving these multi-substituted olefins and then use the resulting knowledge to design semi-synthetic thermosets by incorporating these natural monomers into thiol–ene networks in the most environmentally friendly way possible. Mechanistic kinetic results show that internal 1,2-disubstituted enes found in mono-unsaturated vegetable oils and some macrolactones undergo a fast reversible cis/trans-isomerization process in favour of trans-isomer formation coupled with the thiol–ene mechanism. The slow reactivity of these enes has been accredited not just to the isomerization itself, but predominantly to the chain-transfer hydrogen-abstraction step. This rate-limiting step, however, does not seem to compromise their use in the creation of thiol–ene networks as demonstrated by photopolymerization in the melt of a series of linear globalide/ε-caprolactone-based copolyesters differing in amount of unsaturations along the backbone crosslinked with a tri-functional thiol propionate ester monomer. The resulting thermoset films were amorphous elastomers exhibiting different thermal and mechanical properties depending on the comonomer feed ratio. D-limonene, a renewable diolefinic substrate, proved to be an important terpene in free-radical thiol–ene additions. Empirical results show that the 1,1-disubstituted exo-vinylidene bond is about 6.5 times more reactive than the endocyclic 1,1,2-trisubstituted 1-methyl-cyclohexene moiety when reacting with mercapto propionate esters in organic solution conditions. Kinetic modeling results suggest that the differences in double bond reactivity are partially ascribed to steric impediments coupled with differences in electron-density controlling thiyl-radical insertion onto the two unsaturations but predominantly to differences in relative energy between the two tertiary insertion carbon-centered radical intermediates. Off-stoichiometric manipulations in the thiol–limonene mole ratio, assisted by numerical model simulations, offer a convenient method to visualize and assess the overall reaction system kinetics irrespective of time, thus being regarded as an important guiding tool for organic and polymer chemists aiming at designing thiol–ene reaction systems based on limonene. Multifunctional limonene-terminated thiol–ene macromonomer resins were synthesized in ethyl acetate solution and then reacted in different combinations with polyfunctional mercapto propionate esters to afford semi-synthetic thiol–ene networks with different thermo-viscoelastic properties depending on functionality, crosslink density, homogeneity and excess ofthiol occluded into the networks. The bulky cycloaliphatic ring structure of limonene locked between thioether linkages introduce a certain degree of rigidity to the final networks and increase the glass-transition temperature when compared tomore standard thiol–allyl systems. In all cases evaluated, high thiol–ene conversions were achieved with minimum or no side-reactions such as chain-growth homopolymerization and at reasonable reaction rates.<br><p>QC 20131002</p>
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Chrysanthos, Marie. "Novel biobased epoxy networks derived from renewable resources : Structure-property relationships." Phd thesis, INSA de Lyon, 2012. http://tel.archives-ouvertes.fr/tel-00782119.
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In recent years, bio-based polymers derived from renewable resources have become increasingly important as sustainable and eco-efficient products which can replace the products based on petrochemical-derived stocks. The objective of our work was to develop novel bio-based reactive systems suitable for high performance composite materials especially epoxy systems. The most commonly used starting monomer to formulate epoxy networks is the diglycidyl ether of bisphenol A, DGEBA, derived from bisphenol A and epichlorohydrin. Bio-based epichlorohydrin is commercially available. So the challenge to obtain a fully bio-based epoxy prepolymer is to replace bisphenol A by a bio-based precursor. Another interest for replacing bisphenol A by a bio-based precursor is that bisphenol A has been known to have estrogenic properties. In this study, we studied different bio-based epoxy systems and compared them to a classical DGEBA based system using, in a first step, isophorone diamine (IPD) as conventional curing agent. Bio-based epoxy prepolymers were derived from natural sugars, sorbitol and isosorbide respectively. Sorbitol polyglycidyl ether is available commercially, while isosorbide diglycidyl ether was synthesized either via conventional epoxidation (i.e. using epichlorohydrin) or via the diallyl isosorbide intermediate. Another bio-based epoxy prepolymer was derived from cardanol and is also a commercial product. Chemical structure of the bio-based epoxy prepolymers were analyzed by different analytical methods, gelation and crosslinking reactions were studied using rheological measurements and differential scanning calorimetry, respectively. Properties of the cured networks were evaluated using dynamic mechanical analysis and thermo gravimetric analysis. Influence of the bio-based epoxy prepolymer structure on the system properties as well as the influence of the crosslinking agent structure (either derived from renewable resources or bio-based ones) was discussed. Water absorption of the bio-based networks was also studied.
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Schneider, Ian Michael. "Electricity market integration of stochastic renewable resources : efficiency and risk tradeoffs." Thesis, Massachusetts Institute of Technology, 2017. http://hdl.handle.net/1721.1/108958.
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Thesis: S.M. in Technology and Policy, Massachusetts Institute of Technology, School of Engineering, Institute for Data, Systems, and Society, Technology and Policy Program, 2017.<br>Thesis: S.M. in Electrical Engineering, Massachusetts Institute of Technology, Department of Electrical Engineering and Computer Science, 2017.<br>Cataloged from PDF version of thesis.<br>Includes bibliographical references (pages 55-57).<br>Electricity generation from renewable sources is growing rapidly, but the variability and uncertainty of renewable resources like wind and solar energy can increase the costs of supplying reliable electricity. Competitive markets for wholesale electricity are widely used in the United States, but the regulatory details that govern their treatment of stochastic resources can have significant effects on efficiency and risk. This research analyzes how producers respond to market mechanisms intended to improve forecasting and long-term siting decisions. This thesis characterizes producer equilibrium strategies in competitive short term energy markets by examining the bidding behavior of energy market participants when energy imbalance payments are determined endogenously from market clearing conditions. The results show that the market-based pricing mechanism leads to better tradeoffs of system efficiency and risk compared to the case where penalties are exogenous, suggesting additional benefits of market-based penalty prices beyond those previously studied. This research also explores how long-term market investment equilibria are affected by current energy policies. It presents new analytical results showing how the Production Tax Credit (PTC) biases wind investment towards high-producing sites, but with higher overall levels of wind correlation, which can induce additional costs associated with reliability and system risk.<br>by Ian Michael Schneider.<br>S.M. in Technology and Policy<br>S.M. in Electrical Engineering
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Liu, Xiaoyan. "Share ownership distribution, non-renewable resources extraction rate and pollution intensity." Thesis, Durham University, 2012. http://etheses.dur.ac.uk/6954/.
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There is increasing concern for scarcity of natural resources and deterioration of the environment due to economic activity. Although theoretically the Hotelling rule not only provides an optimal extraction for the resource owner's profit maximization problem but also provides the optimal solution for society as a whole, the rule fails to fit the facts and only applies to the idealised world for which it was constructed. In particularly, when the resource firm realises it can affect its price depending on extraction, shareholders will disagree on the extraction rate. Thus, how to deal with the shareholders' interests and make decisions for resource firms is of central importance. Endogenizing firms' objectives through shareholder voting via majority rule is considered as the solution. This thesis analyzes the behaviour of resources firms in shareholder voting equilibrium when the firms' decisions are taken through shareholder voting. Firstly, theoretical models are formulated for the extraction rate and pollution intensity of resources firms respectively. We show that the share ownership owned by the largest shareholder is an important determinant of extraction rate and pollution intensity. Moreover empirical studies using panel data are conducted to test the hypothesis. We find strong evidence supporting our theoretical implications. As for the extraction rate in resource firms, the results indicate a significant and negative relation between extraction rate and the share owned by the largest shareholder. However, a significantly positive relation is found using oil fields level data. As for the pollution emissions in firms, we find the firm where the largest shareholder holds a larger share will have lower pollution intensity.
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Matsenko, Elena. "Approaches to formation of ecologic-economic classification of renewable natural resources." Thesis, Видавництво СумДУ, 2008. http://essuir.sumdu.edu.ua/handle/123456789/8307.
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Mirabal, Samantha T. "An economic analysis of hydrogen production technologies using renewable energy resources." [Gainesville, Fla.] : University of Florida, 2003. http://purl.fcla.edu/fcla/etd/UFE0002060.
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Sayed, Ahmed [Verfasser]. "Reliability analysis of power systems with variable renewable resources / Ahmed Sayed." München : GRIN Verlag, 2020. http://d-nb.info/1217713468/34.
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Dongre, R. N. "Novel polymeric materials from renewable resources: phenolic resins based on crotonaldehyde." Thesis(Ph.D.), CSIR-National Chemical Laboratory, Pune, 1989. http://dspace.ncl.res.in:8080/xmlui/handle/20.500.12252/3323.
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Schmitz, Anthony. "Effect of oil prices on returns to alternative energy investments." Thesis, Atlanta, Ga. : Georgia Institute of Technology, 2009. http://hdl.handle.net/1853/31843.
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Thesis (M. S.)--Economics, Georgia Institute of Technology, 2010.<br>Committee Chair: Vivek Ghosal; Committee Member: Byung-Cheol Kim; Committee Member: Chun-Yu Ho; Committee Member: Tibor Besedes. Part of the SMARTech Electronic Thesis and Dissertation Collection.
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Hussain, Essam Khalafalla Ali. "Parallel single phase voltage source converters topologies fed from renewable energy resources." Thesis, University of Sheffield, 2013. http://ethos.bl.uk/OrderDetails.do?uin=uk.bl.ethos.632727.
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Ly, Adama 1953. "Resolving Senegal's crisis of renewable natural resources: A framework for policy development." Thesis, The University of Arizona, 1996. http://hdl.handle.net/10150/278576.
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The renewable natural resources (RNR) of Senegal form the basis of socioeconomic development for the population of this Sahelian country of West Africa. However, because of the current maladapted policies and practices, these resources are in a crisis that has led to a major degradation of the socioeconomic and environmental conditions. To solve these socioeconomic and environmental problems, many solutions have been developed and implemented. However, because of their disregard for both socioeconomic and traditional cultural values, these attempted solutions have often contributed to the problems. To resolve this crisis, Senegal needs to adopt a new integrated management approach along with new integrated natural resources tenure and decentralization policies. Considering the country's limited economic means, the urgent need for policy change, and the necessary progressive implementation of a new policy, this new natural resources policy will need to be developed incrementally. It should take into account the existing policies and examine different alternatives from the current ecological, economic, and sociocultural situation.
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Yan, Ya Xue. "Interests & interdependency in Sino-EU renewable energy cooperation." Thesis, University of Macau, 2012. http://umaclib3.umac.mo/record=b2595814.
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Dannecker, Robert Karl Walter. "Wind energy in the built environment : an experimental and numerical investigation of a building integrated ducted wind turbine module." Thesis, University of Strathclyde, 2001. http://oleg.lib.strath.ac.uk:80/R/?func=dbin-jump-full&object_id=20354.
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Wind is now established in Europe as a major 'renewable energy' resource, but its large scale exploitation is increasingly limited by environmental issues. Hence, on the way to a more sustainable development, it is desirable to seek ways to incorporate it into small scale embedded generation. As a first step, a prototype of a small scale Ducted Wind Turbine has been developed and tested, which seems to be feasible for integration into a conventional building. The wind flow around the building generates differential pressures which may cause an enhanced massflow through the turbine. This thesis is concerned with the investigation of the flow through building integrated duct configurations. Hence, pressure and wind speed measurements have been carried out on a wind tunnel model at different angles of incident wind. Different duct geometries with attached spoilers have been tested, and it was confirmed that wind speeds up to 30 % higher than in the approaching free stream are induced in the duct, in some cases tolerating an angle of incident wind up to 60°. The experimental work proceeded in parallel with Computational Fluid Dynamics modelling. Adaptive gridding of the complex full model geometry required a two dimensional approach, which was used to compare the predicted flow behaviour qualitatively. Three dimensional simulation of the flow field in the building integrated duct could be compared with experimental results. A new flow field mapping approach was initialised to form a two stage process in which conditions in the large-scale flow domain, modelled in a coarse three dimensional simulation, are used as boundary conditions for a localised simulation of the duct flow. Based on performance measurements of a free standing prototype in field trials and the experimentally determined wind speed in the duct, a power prediction model was developed. For the Scottish climate, the proposed device compares favorably with conventional small wind turbines and photovoltaics. The presented work evaluates the concept of harvesting wind energy in the built environment and provides outlines for the future design of a building integrated Ducted Wind Turbine module.