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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
101

Serum Antibodies to Human Papillomavirus Type 6, 11, 16 and 18 and Their Role in the Natural History of HPV Infection in Men

Lu, Beibei 01 January 2010 (has links)
Our understanding of humoral immune response to human papillomavirus (HPV) infection has been mainly derived from studies in women. Very little is known about humoral immune response to HPV in men. There is also a growing interest in understanding the burden of HPV exposure in the subgroups of the male population, including men who have sex with women (MSW), men who have sex with men (MSM) and men who have sex with both men and women (MSMW). This dissertation was undertaken to understand and characterize humoral immune response, measured by detectable serum antibody IgG, to HPV 6, 11, 16 and 18 infection, to estimates seroprevalence of HPV 6, 11, 16 and 18, to determine the associations of sociodemographic and sexual behavioral factors with seroprevalence of individual HPV types, and to evaluate the role of serum antibodies in the subsequent acquisition of infection with the same HPV type, genetically related and un-related HPV types. Three studies that compose of this dissertation were conducted within the framework of two longitudinal studies of HPV infection in men: a single-site natural history study of male residents of Tucson, Arizona (the 1st study: N=285); and a multinational natural history study of healthy men residing in São Paulo, Brazil, Cuernavaca, Mexico, and Tampa, Florida (the 2nd study: N=1477; the 3rd study: N=2187). Men were recruited using similar eligibility criteria in both natural history studies and followed every 6 months for a maximum of 18 months in the single-site study and 48 months in the multi-national study. HPV DNA status was assessed using the PGMY09/11 L1 consensus primer system and the Linear Array HPV Genotyping Protocol. Testing of serum antibodies to HPV 6, 11, 16 and 18 was performed with virus-like particle-based ELISA assays. Data from our studies indicate that exposure to HPV 6, 11, 16 and 18, the four HPV types targeted in the currently license HPV vaccines, is common. Of 285 male residents of Tucson, Arizona, 28.8% of them were seropositive to HPV 16 and/or 18 at study entry. Similarly, approximately one third of 1477 participants of the multi-national male HPV natural history study were seropositive to at least one vaccine HPV type, with the percentage of 21.8% in U.S. site, 33.4% in Mexico site, and 49.1% in Brazil site. It is also noted that seroprevalence of individual vaccine HPV types is greatly elevated among men of different sexual practices. Seroprevalence of HPV 6, 11, 16 and/or 18 was twice as high among MSM and MSMW compared to MSW. Likewise, seroprevalence of individual HPV types was two fold or higher among MSW and MSMW. Our findings suggest that the predominant predictors of seropositivity to HPV 6, 11, 16 and 18 are age and same-sex sexual behaviors. Seroprevalence increased with age among young-to-middle-aged men with significant upward age trends observed for HPV 11, 16 and 18. MSM, compared to MSW, more likely to be seropositive to HPV 16 or 18. Similarly, men who practiced same-sex anal sex, compared to those who did not, were significantly more likely to be seropositive to HPV 6, 11, 16 and 18, respectively. Among 276 men free of HPV 16 at enrollment in Tucson, We did not detect statistically significant associations between the baseline serum antibodies to HPV 16 and/or 18 and subsequent risk of infection with homogeneous HPV types or related-HPV types. Of 2187 men residing in three countries who tested HPV 16 negative at enrollment, the risk of subsequent HPV 16 infection was not associated with enrollment HPV 16 serum antibodies status. Our data provide important estimates of population exposure to vaccine HPV types for future studies modeling potential vaccine impact and vaccine cost effectiveness in men. Our findings also support strategic vaccination of males as an effective preventive measure for HPV-related diseases and cancers in men and their sex partners, men and women alike.
102

Strength and Deformation Behavior of Municipal Solid Waste (MSW) Based on Constitutive Modeling Approach

Chouksey, Sandeep Kumar January 2013 (has links) (PDF)
The geotechnical properties of municipal solid waste (MSW) such as compressibility, shear strength and stiffness are of prime importance in design and construction of landfills. However, it is not well clear how the stress-strain and strength characteristics vary with time as the biodegradation of waste continues in the landfill. There is also a need to address the variability of MSW properties and their role in landfill design. The present thesis proposes models for the analyses of stress-strain response of MSW in undrained and drained conditions. The proposed models are based on critical state soil mechanics concept and the modified cam clay model is extended to consider the effects of creep and biodegradation. The models are examined with reference to experimental data and published results of MSW in the form of stress strain response. In addition, the experimental results and the data from published literature are also compared with predictions from hyperbolic model. The proposed models are able to capture the stress strain response of MSW in undrained and drained condition adequately. The applicability of proposed model is presented in terms of shear strength ratio, stiffness ratio and settlement for typical landfill cases. In order to examine the influence of model parameters on shear strength, stiffness ratio and settlement, multilinear regression equations are developed based on response surface method (RSM) for different coefficients of variation (COVs). The effect of variability associated with model parameters is examined using reliability analysis. For better understanding, the present thesis is divided into following seven chapters. Chapter 1 is an introductory chapter, in which the need for use of the constitutive models and its use in engineering response analysis of MSW is presented. Further, the organization of thesis is also presented. Chapter 2 presents various studies with regard to the engineering properties of MSW available in the literature. Different models and approaches proposed by various researchers for the prediction of stress-strain response, time dependent behavior and settlement analysis of the MSW are presented. The uncertainty associated with engineering properties and available methods for reliability analysis and the use of response surface method are presented. Finally, based on the literature review, the scope of the thesis and summary of chapter are presented at the end. Chapter 3 presents composition of MSW, detailed description of the sample preparation, methods adopted in the experimental program and test results of one dimensional compression and consolidated undrained tests. Based on the experimental observations, a constitutive model for municipal solid waste for undrained condition in the framework of modified cam clay model considering mechanical creep and biodegradation mechanisms is proposed. It also provides detailed description of the selection of the input parameters required for the proposed model. Further, the detailed derivation of proposed model and the discussion on evaluation of the input model parameters from triaxial and consolidation tests are presented. The model is examined with reference to the experimental data and published results. The stress strain behavior of MSW is compared with the prediction of stress strain response from hyperbolic model. The comparison of stress strain response is well captured using proposed model for all levels of strain. The major conclusions from the study are presented at the end. Chapter 4 presents experimental results of consolidated drained tests. A constitutive model for MSW for drained condition in the framework of modified cam clay model considering mechanical creep and biodegradation mechanisms is proposed. The model is examined with reference to the experimental data and data from published literature. In addition, stress strain behavior of MSW is compared with the predictions from hyperbolic model. The comparison of stress strain response is well captured using proposed model for all levels of strain. The major conclusions from the study are presented at the end. Chapter 5 presents the applicability of proposed models in terms of shear strength ratio and stiffness ratio for a typical landfill condition. Based on response surface method (RSM), multilinear response surface equations are developed for different variables ( M, λ.b.c.d.Edg ) for different percentages of strain for 10 and 20% COVs of the model parameters. The effect of variability of model parameters is presented in terms of results of reliability analysis for specified performance functions. The major conclusions from the study are presented at the end. Chapter 6 presents an approach for the settlement evaluation of MSW for a typical landfill case of 30 m high. Based on RSM, multilinear response surface equations are developed for the calculation of MSW settlement for 30 years for 10 and 20% COVs. The effect of variability of model parameters is evaluated in term of reliability index for performance function specified in terms of landfill capacity. The major conclusions from the study are presented at the end. Chapter 7 presents a brief summary and conclusions from the various studies reported in the present thesis.
103

Assessment of Leachate Characteristics and Geotechnical Properties of Municipal Solid Waste Landfill

Naveen, B P January 2016 (has links) (PDF)
Solid Waste Management is one of the essential services provided by local bodies to keep the urban areas clean. Often it is poorly rendered as it is unscientific, out-dated and inefficient. With the rapid increase in population, livening standards, the generation rates of solid waste are increasing drastically. The landfill waste includes both organic and inorganic wastes as it is not often effectively segregated before disposal. The problem is acute in developing countries such as India. Bangalore city, with a population of about 10.18 million and more than 2000 industries, generates about 4,500 TPD of municipal solid waste. Of this Presently, various municipal solid waste processing units in Bangalore can handle only about 2100 TPD of waste. Mavallipura landfill developed and operated by M/s. Ramky Environmental Engineers, located 40 km away from Bangalore, is being used for disposing of about 1000 TPD, the installed capacity being only 600 TPD of waste. There are also a few dumps in around Bangalore due to historical reasons and insufficient capacity of various designated landfills. To reclaim the old dump sites/closed landfill sites for infrastructural development, it is necessary to know their geotechnical characteristics. Within the Landfill, the characteristics of the waste may change with depth due to degraded wastes as it has been dumped over a period of time. The physical parameters, chemical properties as well as the geotechnical behaviour of the waste change with depth. MSW is known to be a heterogeneous material of varying constituent types and dimensions, containing elements that degrade with time. To consider MSW as a geo-material to support the foundation of structures such as buildings and pavement, an analysis of the bearing capacity of the foundation and further long-term settlement of MSW is essential. The MSW samples are retrieved from a Mavallipura landfill site, Bangalore and analysed for important geotechnical properties such as compaction characteristics, shear strength, permeability, compressibility behaviour and dynamic properties of MSW using ultrasonic and cyclic triaxial tests. This research thus aims to provide valuable information about landfill sites for reclamation, closure and infrastructural development after the closure of landfills. Scanty data are available on the geotechnical properties of waste from landfill sites with varying degrees of degradation. This landfill site is selected as there is a huge environmental concern regarding the soil and groundwater contamination in the area and also can represent a typical landfill scenario in tropical regions. Quantification, quality assessment, consequent treatment and management of leachate have become a monstrous problem world over. In this context, the present study envisages to study the physicochemical and biological characterization of representative urban municipal landfill leachate and nearby water bodies and attempts to figure out relationships between the various parameters together with understanding the various processes for chemical transformations. The analysis shows intermediate leachate age (5-10 years) with higher nutrient levels i.e. 10,000 - 12,000 mg/l and ~2,000 - 3,000 mg/l of carbon (COD) and nitrogen (TKN) respectively. Elemental analysis and underlying mechanisms reveal chemical precipitation and co-precipitation as the vital processes in leachate pond systems resulting in accumulation of trace metals in these systems. The microbial analysis also correlated with specific factors relevant to redox environments that show a gradient in nature and the abundance of biotic diversity with a change in leachate environment. Finally, the quality and the contamination potential of the sampled leachate were performed with the help of potential leachate index (LPI) analysis and water quality index (WQI) analysis for surrounding water bodies (namely surface pond and open well) of Mavallipura landfill site. A geotechnical testing program has been drawn to evaluate the engineering properties of municipal solid waste samples retrieved from a landfill at Mavallipura at various depths through augur within the landfill dumped area. Laboratory studies included are composition, moisture content, particle size analysis, compaction, permeability, direct shear test, consolidation, triaxial compression test. For the laboratory tests, we had considered maximum particle sizes of less than 4.75 mm only. Standard Proctor Compaction tests yielded a maximum dry density of 7.0kN/m3 at 50% optimum moisture content. The permeability of MSW results shows in the range of 4x10-4 cm/sec. Compression index of MSW is 0.46980 and recompression index of MSW is 0.09454. Results obtained from the rectangular hyperbola method are compared with Casagrande and Taylor methods to prove that this method is reliable equally, and results are reasonably accurate. Based on direct shear tests, the MSW sample exhibited continuous strength gain with an increase in shear strain (16%) to define strength. The cohesion of MSW was 10kPa and friction angle is 34°. Based on the elastic constants results obtained from the direct shear test found to be very soft material. In the triaxial test, the MSW sample exhibited continuous strength gain with an increase in axial strain. The frictional component is increased due to sliding and rolling of fibrous particles over one another resulting in the development of apparent cohesion due to antiparticle bonds within the MSW material. Landfills are an integral part of waste management, and disastrous consequences can happen if seismic vulnerability of these landfills is not considered. Dynamic properties of MSW are required to perform seismic response analysis of MSW landfills, but there is no good understanding of the dynamic shear strength of MSW in literature. A comprehensive laboratory cyclic triaxial testing program has been taken up to determine the properties at different densities, confining pressures and shear strains. MSW degrades with time, and its shear modulus and damping are expected to vary with time and degradation. For the density of 6 kN/m3 the dynamic shear modulus values for MSW varied from 0.68 MPa to 5.38 MPa and damping ratio varied from 20% to 40% for MSW. For the density of 7 kN/m3 the dynamic shear modulus values for MSW varied from 1.8 MPa to 7.5 MPa and Damping ratio varied from 23% to 40% for MSW. For the density of 8kN/m3 dynamic shear modulus values for MSW varied from 2.46 MPa to 8.00MPa and damping ratio varied from 16% to 33% for MSW. Also, the ultrasonic testing method was used for determining the dynamic properties at low strains. The Ultrasonic test results indicated that with an increase in density of the sample and with decreased void ratio, the pulse propagation velocity (Vp) increases. With an increase in the density, the shear wave velocity and elastic constants (elastic modulus and shear modulus) increase. The elastic constant values obtained from the ultrasonic test are higher compared to values obtained from unconsolidated-undrained triaxial tests. Also, the carbon stored in the buried organic matter in Mavallipura landfill is estimated. Total organic carbon increases steeply with an increase in depth and is significantly high at a depth of 6 m. Subsurface properties cannot be specified but must be analysed through in-situ tests. The in-situ testing that are carried out in a landfill are boring, sampling, standard penetration test (SPT), dynamic cone penetration test (DCPT) and plate load tests (under static and cyclic condition). A correlation between corrected SPT ‘N’ values and measured using shear wave velocities has been developed for Mavallipura landfill site. Results show that the corrected SPT- N values increase with depth. Corrected N-values are used in the landfill design, so they are consistent with the design method, and correlations are useful. The results obtained from the dynamic cone penetration tests shows lower value when to compare with standard penetration test. The unit weight profile with depth ranged from a low unit weight of 2.48 kN/m3 near the surface to a highest value of approximately 9.02 kN/m3 at a depth of 6 m. The highest temperatures for landfills were reported at mid-waste elevations with temperatures decreasing near the top. The bearing pressure-settlement curves for plate size 75cm and 60cm presented similar behaviour while the plate size of 60cm curve presents a lesser settlement of 70mm, compared to with plate size of the 75cm curve with the settlement of 80mm and failure mode could be classified as punching shear. The cyclic plate load test with plate size of 60cm and 75cm were carried out on the soil cover. The elastic constants were found to be 73.87 and 96.84 kPa/mm and for 60 and 75cm plates respectively. Geophysical testing may not be as precise but has the benefit of covering large areas at small costs and sometimes can locate features that might be missing by conventional borings. Multichannel analysis of surface waves (MASW) is an indirect geophysical method used in the landfill for the characterization of the municipal solid waste site. The Mavallipura landfill was surveyed up to the length of about 35m at the top level. A series of one-dimensional and two-dimensional MASW surveys used active seismic sources such as sledgehammer (5kg) and propelled energy generator (PEG-40) was used. This hammer was instrumented with geophones to trigger record time. All the testing has been carried out with geophone spacing of 1m and recorded surface wave arrivals using the source to first receiver distance as 5m with recording length of 1000 millisecond and the recording sampling interval of 0.5 milliseconds (ms) were applied. Results shows that the PEG-40 hammer can generate the longest wavelength with a maximum depth of penetration. The shear wave velocity varies from 75 to 155 m/s with an increase in depth of about 27.5m. Based on the site characterization at the landfill site, it was found that the Mavallipura landfill site can be categorized as very loose, and it is still in a continued stage of degradation. Shear wave and P-wave velocity profile for eight major locations in the study area were determined and variation of waste material stiffness corresponding to the in-situ state with depth, was also evaluated. Also, MASW survey has been carried out to develop dispersion curve on another landfill site at Bhandewadi, Nagpur. MASW system consisting of 24 channels geode seismograph with 24 geophones of 4.5Hz capacity is used in this investigation. The seismic waves were created by sledgehammer with 30cmx 30cmx2cm size hammer plate with ten shots. These waves were captured by the geophones/receivers and further analyzed by inversion. The results indicated that near surface soils(less than 3m depth) approximately the to 5mm, and with 85% of dry weight basis of waste particles with sizes less than 10mm, the shear wave velocity varies from 75 to 140 m/s (frequency ranges from 30 to 23Hz). With the increase in 6.5m depth, the shear wave velocity ranged from 140 to 225m/s (frequency ranges 23 to 13Hz). Overall, the results of the study showed that seismic surveys have the potential to capture the changes in dynamic properties like shear wave velocity and Poisson’s ratio of the depth of MSW landfill to infer the extent of degradation and provide dynamic properties needed for seismic stability evaluations. Based on the in situ and laboratory results of this study and a review of the literature, the unit weight, shear wave velocity, strain-dependent normalized shear modulus reduction and material damping ratio relationships for Mavallipura landfill are developed and also validated using semi-empirical methods. Finally, seismic response analysis of Mavallipura landfill has been carried out using the computer programs like SHAKE 2000 and DEEPSOIL. Results show that the unit weight is increased with depth in response to the increase in overburden stress. The proposed material damping ratio and normalized shear modulus reduction curve lie close to the profile given in the literature for landfills composed of waste materials with 100% particles sized less than 20mm. Peak spectral acceleration at 5% damping value is 0.7g for 0.07 sec in SHAKE 2000 and peak spectral acceleration at 5% damping value is 0.63g for 0.04 sec in DEEPSOIL. Amplification ratio is 6.11 at 1.1l Hz in SHAKE2000 and 4.65 at 2.67Hz in DEEPSOIL. Peak ground acceleration (PGA) for the landfill site, it is observed PGA has decreased from 0.3g to 0.15g in DEEPSOIL and PGA has decreased from 0.33g to 0.15g in SHAKE2000. The studies presented in the thesis brought out the importance of characterization of municipal solid waste leachate regarding metabolism and treatment/degradation of Mavallipura landfill leachate. For municipal solid waste of with sizes ranging from 0.08 coefficient of permeability being about 10-4 cm/sec, the compression index was about 0.47. A more reliable method of calculating the coefficient of consolidation has been recommended. Correlations between shear wave velocity and SPT-N values has been developed for the Mavallipura landfill site. The results showed that the dynamic cone penetration tests values are lower than indicated by standard penetration tests. The cyclic plate load tests carried out with plate sizes of 75cm and 60cm showed that elastic constants of 96.84 kPa/mm and 73.87kPa/mm respectively. MSW properties evaluated in this thesis are compared with those of soft clays. The MSW properties showed higher values (strength and SBC) and lower values of compressibility, compared with those of soft clays. Thus foundation improvement on MSW is less challenging than foundations on soft soils. Also stabilization of MSW with other solid wastes such as fly ash can be considered as an economical option. Based on detailed studies the importance of unit weight, shear wave velocity, strain-dependent normalized shear modulus reduction and material damping ratio relationships for landfill waste have been developed. Based on the site characterization, the waste landfill has been categorized as very loose material, which is still in a degradation process. SHAKE2000 software shows higher PGA value comparing with DEEPSOIL.
104

[en] THE MECHANICAL BIOLOGICAL TREATMENT WASTE IN THE CITY OF RIO DE JANEIRO / [pt] O TRATAMENTO MECÂNICO E BIOLÓGICO NA GESTÃO DE RESÍDUOS NO MUNICÍPIO DO RIO DE JANEIRO

JUSSARA OLIVEIRA DO NASCIMENTO 02 May 2019 (has links)
[pt] O aumento da produção mundial de resíduos e a falta de programas de gestão adequados a estes resultam no descarte e disposição inadequadas, causando inúmeros impactos ambientais e afetando, inclusive, à saúde humana. Tais resíduos, por apresentarem alto poder calorífico, versatilidade e resistência, devem ser tratados como matéria prima pós-consumo e não como lixo, podendo ser utilizados de inúmeras formas. Uma delas é a reciclagem, um processo que apresenta nova utilização aos resíduos antes designados como lixo, gerando possibilidades de rentabilidade e emprego. A reciclagem tem grande importância na gestão social de um município, pois está ligada diretamente às classes de baixa renda. Tais processos têm crescido no Brasil, principalmente após a publicação da Política Nacional de Resíduos Sólidos (PNRS) - Lei n 12.305, que exige um plano de resíduos para cada município, incentivando a reciclagem e compostagem de lixo. Ainda assim, o problema persiste, devido à falta de programas de coleta seletiva, falta de incentivo aos recicladores e catadores, bem como descaso dos governos e da população. A probabilidade de melhoria é grande, porém demandará muito tempo e investimento. O tratamento mecânico e biológico é apresentado então como uma solução para o cumprimento dos objetivos no tratamento de resíduos em curto prazo. Este trabalho tem o objetivo de analisar tal tecnologia e sua aplicação no município do Rio de Janeiro, avaliando suas vantagens, desvantagens e restrições para este processo. / [en] The progress of humanity and the encouragement of increased consumerism have generated the supply and mass consumption products. A greater extent, so does the production of waste in the world, together with the scarcity of non-renewable resources in the long term, climate change, have diverted attention to environmentally sustainable practices involving waste management. In this context, the Management of Municipal Solid Waste (MSW), translates into a complex process that requires multidisciplinary views, working from the logistics in the process of collection, storage and disposal of waste to the Biology, Chemistry and Thermodynamics, given the diversity of techniques and technologies available for your treatment and recovery in the market. Social development is also an important point, since in countries like Brazil recycling is an activity that generates resources for social classes with lower purchasing power. In addition to operating in the production of consumer goods from waste, much of the recyclable materials back to the market due to the work of sorters, people with very low income, who are in this profession a form of survival. These factors are relevant to the implementation of any management system, which requires significant investment and participation of the public authorities, both legislative and executive. Developed countries, such as members of the European Union (EU), are far ahead in MSW Management, seeking ways of dealing with their waste less and less impactful to the environment. Brazil still is a more technical phase and less practical than the EU, but has important advances. In 2010, entered into force on National Solid Waste Policy (NSWP), established by Law 12.305. This Policy establishes strategies and deadlines for the Brazilian sustainable development, reviews the hierarchy of priorities in waste treatment and imposes the reverse logistics system, and treat life-cycle of products and encourage the reuse, recycling of materials and composting waste, eliminating the dumps and leaving foster landfilling, lagging only this waste without a more favorable allocation to the environment and saving resources.
105

Dynamics of quarks and leptons : theoretical Studies of Baryons and Neutrinos

Ohlsson, Tommy January 2000 (has links)
The Standard Model of Elementary Particle Physics (SM) is the present theoryfor the elementary particles and their interactions and is a well-established theorywithin the physics community. The SM is a combination of Quantum Chromodynamics(QCD) and the Glashow{Weinberg{Salam (GWS) electroweak model. QCDis a theory for the strong force, whereas the GWS electroweak model is a theoryfor the weak and electromagnetic forces. This means that the SM describes allfundamental forces in Nature, except for the gravitational force. However, the SMis not a nal theory and some of its problems will be discussed in this thesis.In the rst part of this thesis, several properties of baryons are studied suchas spin structure, spin polarizations, magnetic moments, weak form factors, andnucleon quark sea isospin asymmetries, using the chiral quark model (QM). TheQM is an eective chiral eld theory developed to describe low energy phenomena of baryons, since perturbative QCD is not applicable at low energies. The resultsof the QM are in good agreement with experimental data.The second part of the thesis is devoted to the concept of quantum mechanicalneutrino oscillations. Neutrino oscillations can, however, not occur within the GWSelectroweak model. Thus, this model has to be extended in some way. All studiesincluding neutrino oscillation are done within three avor neutrino oscillationmodels. Both vacuum and matter neutrino oscillations are considered. Especially,global ts to all data of candidates for neutrino oscillations are presented and alsoan analytical formalism for matter enhanced three avor neutrino oscillations usingtime evolution operators is derived. Furthermore, investigations of matter eectswhen neutrinos traverse the Earth are included.The thesis begins with an introductory review of the QM and neutrino oscillationsand ends with the research results, which are given in the nine accompanyingscientic articles. / QC 20100616
106

Evaluation of the Engineering Properties of Municipal Solid Waste for Landfill Design

Lakshmikanthan, P January 2015 (has links) (PDF)
The objective of this thesis is to evaluate the engineering properties of Municipal Solid Waste (MSW) that are necessary in the design of landfills. The engineering properties of MSW such as compressibility, shear strength, stiffness and hydraulic conductivity are crucial in design and construction of landfills. The variation of the engineering properties with time, age and degradation are of paramount importance in the field of landfill engineering. There is a need to address the role of the engineering properties in landfill engineering as it is not apparent how the engineering characteristics vary with time. The thesis presents the results of study of the engineering properties of MSW comprehensively and develops experimental data for design of MSW landfills. The work includes the study of the index properties and the engineering properties of MSW such as compressibility, shear strength, shear modulus and damping ratio and a detailed experimental study of the bioreactor landfill. The components of settlements, variation of shear strength with respect to unit weight and particle size are determined experimentally and analyzed. The dynamic properties such as shear modulus and material damping ratio and its variation with parameters such as unit weight, load, amplitude, degradation and moisture content are studied and analyzed. The normalized shear modulus reduction curve which is used in the seismic analysis of the landfills is developed for MSW based on the experimental results and previous studies. A pilot-scale bioreactor was setup in the laboratory for long term monitoring of the settlement, temperature variation and gas production simultaneously. The parameters of interest viz, pH, BOD, COD, conductivity, alkalinity, methane and carbon-di-oxide were determined. The generated data can be effectively used in the engineered design of landfills. For a better understanding, the present thesis is divided into the following eight chapter Chapter 1 provides a general introduction to the thesis with respect to the importance of engineering properties of MSW and presents the organization of the thesis. Chapter 2 presents a detailed review of literature pertaining to the basic, index and the engineering properties of MSW namely compressibility, shear strength, shear modulus and damping ratio, bioreactor landfill and also the scope of the study. Chapter 3 includes the materials and methods followed in the thesis. Chapter 4 presents the evaluation of compressibility characteristics of MSW including the components of settlement and the settlement model parameters. Chapter 5 presents the determination of the shear strength properties of MSW using direct shear tests and triaxial tests. The variation of the strength with respect to unit weight and the particle size is examined. The results are examined in terms of strength ratio and stiffness ratio and the implications are discussed. Chapter 6 presents the study of the dynamic characters of MSW. The variation of the shear modulus and damping ratio with respect to unit weight, confining pressure, loading frequency, decomposition and moisture content are analyzed. Normalized shear modulus reduction and damping curves are proposed for seismic analysis. Chapter 7 presents the study of the conventional and the bioreactor landfill in a small scale laboratory setup. A large scale experimental setup is fabricated to study the characteristics of a bioreactor landfill and includes the long term monitoring and analysis of temperature, gas, settlement and leachate characteristics periodically. The results of the comprehensive study are presented in this chapter. Chapter 8 summarizes the important conclusions from the various experimental studies reported in this dissertation. Conclusions and the scope of future work are presented. A detailed list of references and the list of publications from the thesis are presented at the end. Appendix A presents the life cycle analysis and life cycle cost analysis of MSW land disposal options. The land disposal options such as open dumps, engineered landfills and bioreactor landfills are analyzed in this study.
107

Molecular mobility. Structure-property relationship of polymeric materials

Carsí Rosique, Marta 07 January 2016 (has links)
Tesis por compendio / [EN] The present work examines the influence of the chemical structure of polymers on thermal, mechanical and dielectric behavior. The experimental techniques used for the purpose are differential scanning calorimetry, dynamo-mechanical analysis and dielectric spectroscopy. Additionally, in order to confirm the results obtained using the above methods, other techniques such as ray diffraction have also been employed. Chapters 1 and 2 contain the introduction and the objectives, respectively. Chapter 3 briefly describes the experimental techniques used. Chapter 4 contains the findings of the comparative analysis of the response to electrical noise fields for three poly(benzyl methacrylates) with different structures. The analysis was carried out under a wide range of frequencies and temperatures on three poly(benzyl methacrylates) containing two dimethoxy groups in positions 2,5-, 2,3- and 3,4-. The results show that the position of the dimethoxy groups on the aromatic ring has a significant effect on the molecular dynamics of poly(benzyl methacrylate). The spectra obtained were of high complexity and therefore, in order to perform a better analysis, numerical methods for time-frequency transformation including the use of parametric regularization techniques were used. We studied the effect of this structural change on the secondary relaxation processes and relaxation process , relating to the glass transition. We also analyzed the effect of the dimethoxy group position on the formation of nanodomains, in which the side chains are predominant, and on the conduction processes of the materials tested. In Chapter 5, the conductivity of rubbery liquids was studied by analyzing poly(2,3-dimethoxybenzyl methacrylate), which exhibits its own particular behavior. The chapter analyzes the principle of time-temperature superposition, employing different interrelated variables. Chapter 6 focuses on how the presence of crosslinking affects the molecular mobility of polymethacrylates containing aliphatic alcohol ether residues. In this case, the effect of crosslinking on the secondary and primary relaxation processes was analyzed. The creation of nanodomains in the side chains as a result of the presence of crosslinking was also studied. / [ES] En este trabajo se presenta un estudio de la influencia de la estructura química de los polímeros en su comportamiento térmico, mecánico y dieléctrico. Las técnicas experimentales empleadas para ello han sido la calorimetría diferencial de barrido, el análisis dinamo-mecánico y la espectroscopia dieléctrica. Adicionalmente, se han empleado otras técnicas como la difracción de rayos, con objeto de corroborar los resultados obtenidos por las primeras. En los Capítulos 1 y 2 se recoge la introducción y los objetivos, respectivamente. El Capítulo 3 presenta una breve descripción de las técnicas experimentales empleadas. En el Capítulo 4 se recogen los resultados obtenidos en el análisis comparativo de la respuesta a campos de perturbación eléctrica en un amplio rango de frecuencias y temperaturas para tres polimetacrilatos de bencilo con dos grupos dimetoxi en posiciones 2,5-, 2,3- y 3,4-. Los resultados obtenidos señalan el importante efecto de la posición de los grupos dimetoxi en el anillo aromático, sobre la dinámica molecular del polimetacrilato de bencilo. Los espectros obtenidos fueron muy complejos, por ello en orden a llevar a cabo un mejor análisis se emplearon métodos numéricos para la transformación tiempo-frecuencia que incluyeron el uso de técnicas de regularización paramétrica. Se ha estudiado el efecto que dicho cambio estructural ejerce tanto sobre los procesos de relajación secundaria como sobre el proceso de relajación α, relacionado con la transición vítrea. Así mismo, se ha analizado el efecto de la posición de los grupos dimetoxi en la formación de iii nanodominios en los que predominan las cadenas laterales, y su efecto en los procesos de conducción de los materiales analizados. En el Capítulo 5 se recoge el estudio de la conductividad de líquidos gomosos tomando como modelo el poli (metacrilato de 2,3-dimetoxibencilo), por su peculiar comportamiento. En este capítulo se ha realizado un análisis del principio de superposición tiempo-temperatura, empleando para ello diferentes variables relacionadas entre sí. En el Capítulo 6 se recoge el efecto de la presencia de entrecruzante en la movilidad molecular de polimetacrilatos que contienen residuos de éteres de alcoholes alifáticos. En este caso, se ha analizado el efecto de la presencia de entrecruzante tanto en los procesos de relajación secundarios, como en el proceso de relajación principal. También se llevó a cabo un análisis del efecto que la presencia de entrecruzante tiene sobre la creación de nanodominios gobernados por las cadenas laterales. / [CA] En aquest treball es presenta un estudi de la influència de l'estructura química dels polímers en el seu comportament tèrmic, mecànic i dielèctric. Les tècniques experimentals utilitzades han sigut la calorimetria diferencial de rastreig, l'anàlisi dinamo-mecànic i l'espectroscòpia dielèctrica. Addicionalment, s'han empleat altres tècniques com la difracció de rajos X a fi de corroborar els resultats obtinguts per les primeres. En els Capítols 1 i 2 s'arreplega la introducció i els objectius, respectivament. Al Capítol 3 es presenta una breu descripció de les tècniques experimentals emprades. En el Capítol 4 es recull els resultats obtinguts en l'anàlisi comparativa de la resposta a camps de pertorbació elèctrica en un ampli rang de freqüències i temperatures de tres polimetacrilats de benzil amb dos grups metoxi en posicions 2,5-, 2,3- i 3,4-. Els resultats obtinguts assenyalen l'important efecte de la posició dels grups metoxi en l'anell aromàtic, sobre la dinàmica molecular del polimetacrilat de benzil. Els espectres obtinguts van ser molt complexos, per aquesta raó per a dur a terme un millor anàlisi es van emprar mètodes numèrics per a la transformació temps-freqüència que van incloure l'ús de tècniques de regularització paramètrica. S'ha estudiat l'efecte que el dit canvi estructural exerceix tant sobre els processos de relaxació secundària com sobre el procés de relaxació , relacionat amb la transició vítria. Així mateix, s'ha analitzat l'efecte de la posició dels grups metoxi en la formació de nanodominis en els que predominen les cadenes laterals, i el seu efecte en els processos de conducció dels materials analitzats. En el Capítol 5 s'arreplega l'estudi de la conductivitat de líquids gomosos prenent com a model el poli-(metacrilat de 2,3-dimetoxibencilo), pel seu peculiar comportament. En aquest capítol s'ha realitzat un anàlisi del principi de superposició temps-temperatura, emprant per a això diferents variables relacionades entre sí. En el Capítol 6 s'arreplega l'efecte de la presència d'entrecreuat en la mobilitat molecular de polimetacrilats que contenen residus d'èters d'alcohols alifàtics. En aquest cas, s'ha analitzat l'efecte de la presència d'entrecreuat tant en els processos de relaxació secundaris, com en el procés de relaxació principal. També es va dur a terme un anàlisi de l'efecte que la presència d'entrecreuat químic té sobre la creació de nanodominis governats per les cadenes laterals. / Carsí Rosique, M. (2015). Molecular mobility. Structure-property relationship of polymeric materials [Tesis doctoral]. Universitat Politècnica de València. https://doi.org/10.4995/Thesis/10251/59460 / TESIS / Premios Extraordinarios de tesis doctorales / Compendio

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