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No / The Helmholtz integral equation formulation is used to produce the solution for the acoustic field reflected from a finite, thin, poroelastic plate in a rigid baffle with simply supported edges. The acoustic properties of the porous material are predicted using the effective fluid assumption. The solutions for the displacement of the plate and for the loading acoustic pressures are given in the form of the sine transform. The sine transform coefficients are obtained from the solution of a system of linear equations resulting from three integral Helmholtz formulations which relate the displacement of the plate and the acoustic pressures on the front and on the back of the plate. The effect of an air gap behind the plate in the front of a rigid wall is also considered. A parametric study is performed to predict the effect of variations in the parameters of the poroelastic plate. It is shown that thin, light, poroelastic plates can provide high values of the acoustic absorption even for low frequency sound. This effect can be exploited to design compact noise control systems with improved acoustic performance.

Currently, China is facing a challenge of sustainable development. The worsening air quality and increasing haze days in Beijing and many other cities in China have exerted serious health impacts and an economic toll. Pollution control and emission reduction have become an urgent issue that Chinese governments need to tackle. Hence, stricter Environmental laws and Clean Air Plans have been published and implemented in recent years in China. The developed countries had experienced the similar industrial development accompanying by air pollution problem during the middle of last century. Environmental legislating against helped many developed countries solve the pollution and achieved positive EKC trend – air quality improvements along with continuous economic growth. The thesis tries to study the previous lessons and experiences on pollution abatement from some developed countries and find what lesson’s China can draw from them on pollution control and changing towards a sustainable development. The thesis adopts a multi-scientific study method including case studies, economic, technological, legal and institutional analysis. The pollution abatement cases are from the US and UK, because historically the serious air smog episodes due to industrialization had happened in many cities of the two countries, which are like what is happening in China now. Case studies compare the pollution problem in Beijing, Los Angeles and London, and focus on how environmental laws work for emission reduction. The study results show that the economic phase in China now is close to the EKC turning point and is at similar phase comparing to the historical pollution treatment stages during the middle of last century in the US and UK. However, the positive EKC trend does not inevitably come without strong environmental legislation, technological development and economic-social institution sustainability transformation. The implication for China is that the current pollution control laws and its implementation in China at the crucial moment would most likely decide the future environmental, economic, and social situation in China. Loose environmental laws might cause environmental indulgence, while implementation of scientific environmental laws and standards can work effectively on emission reduction and enhancing technology and economic development at the same time. And the scientific based legislation skills from developed countries provide a good lesson to be drawn for China on how to make the laws and standards.

This thesis employs a parametric input distance function that incorporates both desirable and undesirable outputs to provide a more complete representation of the production technology. Based on the Shephard (1970) theory of duality, we derive the shadow prices of undesirable outputs in the Czech energy sector on the data over the period 2002 - 2007. The medians of our shadow prices estimates are 8374, 1198, 2805, 6051 and 8549 € per ton of PM, SO2, NOx, CO and VOC, respectively. We decompose shadow prices estimates and test the hypotheses that the marginal abatement cost decline over time; that marginal abatement cost rice with the declining emission level; and that marginal abatement cost rice with declining emission rate. Key Words: shadow prices, distance function, undesirable outputs, marginal abatement cost JEL classification: C61, D24, Q53

Introdução É importante o desenvolvimento de sistemas de controle de poluição do ar que sejam eficientes, além de aplicáveis à condição nacional e pra proteção da saúde humana, uma vez que os compostos do grupo BTEX são tóxicos. Objetivo - Avaliar o desempenho de sistema de tratamento biológico para vapores de BTEX e investigar as melhores condições de operação para os critérios de projeto adotados. Métodos. Trata-se de trabalho experimental com utilização de unidade piloto constituída de coluna de vidro (diâmetro interno de 80 mm e altura total de 1,2 m) tendo no seu interior um meio filtrante composto vegetal e anéis de Pall - que serviram de suporte para os microrganismos e onde se realizou a biodegradação. Foram monitorados parâmetros como temperatura, perda de carga, vazão, concentração dos gases na entrada e na saída, que constituíram a base para desenvolver intervenções e melhorar seu desempenho. A análise dos gases foi feita por fotoionização (PID) em aparelho portátil. Conclusões - Conclui-se que é viável o tratamento biológico para remoção do BTEX de efluentes gasosos, nas condições operacionais adotadas, com eficiência máxima de remoção em torno de 90 por cento . A máxima eficiência foi obtida para tempo de retenção de 2,4 min., carga superficial do gás de 11,9 m3/m2xh, carga mássica no leito de 67 g/m3xh e capacidade de eliminação de 4 g/m3xh. O uso de anéis de Pall misturados ao composto evitou que valores elevados de perda de carga. Foi relevante a participação da adsorção. A utilização de composto mostrou-se viável como alternativa para a biodegradação do BTEX, fortalecendo seu uso com essa prática ambiental / Introduction - It is important to develop control systems for air pollution that are efficient, applicable to the national condition and to the protection of human health, since the group BTEX compounds are toxic. Objective - To evaluate the performance of biological treatment system for BTEX vapors and investigate the best operating conditions for the design criteria adopted. Methods - This experimental work used a pilot plant consisting of a glass column (internal diameter 80 mm and height of 1.2 m) filled with a filter medium - compost and Pall rings - which supported microorganisms and where biodegradation was carried out. Parameters were monitored such as temperature, pressure drop, flow rate, gas concentration at the inlet and outlet, which formed the basis for developing interventions and improve their performance. The gas analysis was measured by photoionization (PID) in a portable device. Conclusions -. We conclude that it is feasible biological treatment for removal of BTEX emissions, operating in the adopted conditions, with maximum removal efficiency (ER) of around 90 per cent . The maximum efficiency was obtained for empty bed retention time (EBRT) of 2.4 min, surface loading (SL) of 11.9 m 3 /m 2 xh, concentration load (CL) g/m3xh 67 and elimination capacity (EC) of 4 g/m 3 xh. The use of Pall rings mixed with the compost prevented high levels of pressure drop. It is relevant the participation of adsorption process. The use of compost proved to be feasible as an alternative to the biodegradation of BTEX, strengthening its use in the environmental practice

Introdução É importante o desenvolvimento de sistemas de controle de poluição do ar que sejam eficientes, além de aplicáveis à condição nacional e pra proteção da saúde humana, uma vez que os compostos do grupo BTEX são tóxicos. Objetivo - Avaliar o desempenho de sistema de tratamento biológico para vapores de BTEX e investigar as melhores condições de operação para os critérios de projeto adotados. Métodos. Trata-se de trabalho experimental com utilização de unidade piloto constituída de coluna de vidro (diâmetro interno de 80 mm e altura total de 1,2 m) tendo no seu interior um meio filtrante composto vegetal e anéis de Pall - que serviram de suporte para os microrganismos e onde se realizou a biodegradação. Foram monitorados parâmetros como temperatura, perda de carga, vazão, concentração dos gases na entrada e na saída, que constituíram a base para desenvolver intervenções e melhorar seu desempenho. A análise dos gases foi feita por fotoionização (PID) em aparelho portátil. Conclusões - Conclui-se que é viável o tratamento biológico para remoção do BTEX de efluentes gasosos, nas condições operacionais adotadas, com eficiência máxima de remoção em torno de 90 por cento . A máxima eficiência foi obtida para tempo de retenção de 2,4 min., carga superficial do gás de 11,9 m3/m2xh, carga mássica no leito de 67 g/m3xh e capacidade de eliminação de 4 g/m3xh. O uso de anéis de Pall misturados ao composto evitou que valores elevados de perda de carga. Foi relevante a participação da adsorção. A utilização de composto mostrou-se viável como alternativa para a biodegradação do BTEX, fortalecendo seu uso com essa prática ambiental / Introduction - It is important to develop control systems for air pollution that are efficient, applicable to the national condition and to the protection of human health, since the group BTEX compounds are toxic. Objective - To evaluate the performance of biological treatment system for BTEX vapors and investigate the best operating conditions for the design criteria adopted. Methods - This experimental work used a pilot plant consisting of a glass column (internal diameter 80 mm and height of 1.2 m) filled with a filter medium - compost and Pall rings - which supported microorganisms and where biodegradation was carried out. Parameters were monitored such as temperature, pressure drop, flow rate, gas concentration at the inlet and outlet, which formed the basis for developing interventions and improve their performance. The gas analysis was measured by photoionization (PID) in a portable device. Conclusions -. We conclude that it is feasible biological treatment for removal of BTEX emissions, operating in the adopted conditions, with maximum removal efficiency (ER) of around 90 per cent . The maximum efficiency was obtained for empty bed retention time (EBRT) of 2.4 min, surface loading (SL) of 11.9 m 3 /m 2 xh, concentration load (CL) g/m3xh 67 and elimination capacity (EC) of 4 g/m 3 xh. The use of Pall rings mixed with the compost prevented high levels of pressure drop. It is relevant the participation of adsorption process. The use of compost proved to be feasible as an alternative to the biodegradation of BTEX, strengthening its use in the environmental practice

Pollutants follow various subsurface and surface water pathways from sources within a catchment to its outlet and may cause detrimental effects on downstream water quality and ecosystems. Along their different transport pathways through a catchment, pollutants may be attenuated subject to different physical and biogeochemical processes. In this thesis, physical process effects on such catchment-scale pollutant transport and attenuation, resulting coastal pollutant loading and its efficient abatement are investigated. For this purpose, pollutant transport-attenuation is modeled both generically using a Lagrangian Stochastic Advective-Reactive (LaSAR) approach and site specifically for the Swedish Norrström basin using the GIS-based dynamic nitrogen transport-attenuation model POLFLOW. Furthermore, the role of such modeling for catchment-scale pollutant abatement is also investigated by use of economic optimization modeling. Results indicate that appropriate characterization of catchment-scale solute transport and attenuation processes requires accurate quantification of the specific solute pathways from different sources in a catchment, through the subsurface and surface water systems of the catchment, to the catchment outlet. The various physical processes that act on solute transported along these pathways may be quantified appropriately by use of relevant solute travel time distributions for each water subsystem that the pathways cross through the catchment. Such distributions capture the physical solute travel time variability from source to catchment outlet and its effects on reactive pollutant transport. Results of this thesis show specifically that neglect of such physical solute travel time variability in large-scale models of nitrogen transport and attenuation in catchments may yield misleading model estimates of nitrogen attenuation rates. Results for nitrogen abatement optimization in catchments further indicate that inefficient solutions for coastal nitrogen load reduction may result from simplifying physical transport assumptions made in different catchment-scale nitrogen transport-attenuation models. Modeling of possible future nitrogen management scenarios show also that slow nitrogen transport and reversible mass transfer processes in the subsurface water systems of catchments may greatly delay and temporally redistribute coastal nitrogen load effects of inland nitrogen source abatement over decades or much longer. Achievement of the national Swedish environmental objective to reduce the anthropogenic coastal nitrogen loading by 30% may therefore require up to a 40% reduction of both point sources, for achieving a fast coastal load response, and diffuse sources, for maintaining the coastal load reduction also in the long term. / QC 20100908

As part of the EPA’s initiative to reduce the hypoxic zone in the Gulf of Mexico, a feasibility study for a potential water quality trading (WQT) program in the Kentucky River Watershed (KRW) was conducted. While theoretically, emission trading programs are among the most efficient means of reducing pollution, empirical evidence suggests low-trade volume as a primary concern for the long-term success of such programs. Some of the important reasons for the low volume of trade are due to lack of suitable market trading mechanism for point sources and lack of information on willingness to pay (WTP) for abatement credits. Our study aims to tackle these issues by gathering a profile of municipal sewage treatment plants as point source polluters in the KRW, while simultaneously analyzing their preferences for WQT market mechanisms and WTP using a survey based approach. The survey was conducted in 2012. Municipal sewage treatment plants’ ranked preferences are analyzed using an exploded logit model and WTP is analyzed using Ordinary Least Squares and Tobit models.

The negative consequences of rising global energy use have led governments and businesses to pursue methods of reducing reliance on fossil fuels. Plug-In Hybrid Electric Vehicles (PHEVs) and wind power represent two practical methods for mitigating some of these negative consequences. PHEVs use large onboard batteries to displace gasoline with electricity obtained from the grid, while wind power generates clean, renewable power that has the potential to displace fossil-fuel power generation. The emissions reductions realized by these technologies will be highly dependent on the energy system into which they are integrated, and also how they are integrated. This research aims to assess to cost of reducing emissions through the integration of PHEVs and wind power in three Canadian jurisdictions, namely British Columbia, Ontario and Alberta. An Optimal Power Flow (OPF) model is used to assess the changes in generation dispatch resulting from the integration of wind power and PHEVs into the local electricity network. This network model captures the geographic distribution of load and generation in each jurisdiction, while simulating local transmission constraints. A linear optimization model is developed in the MATLAB environment and is solved using the ILOG CPLEX Optimization package. The model solves a 168-hour generation scheduling period for both summer and winter conditions. Simulation results provide the costs and emissions from power generation when various levels of PHEVs and/or wind power are added to the electricity system. The costs and emissions from PHEV purchase and gasoline displacement are then added to the OPF results and an overall GHG reduction cost is calculated. Results indicate that wind power is an expensive method of GHG abatement in British Columbia and Ontario. This is due to the limited environmental benefit of wind over the nuclear and hydro baseload mixtures. The large premium paid for displacing hydro or nuclear power with wind power does little to reduce emissions, and thus CO2e costs are high. PHEVs are a cheaper method of GHG abatement in British Columbia and Ontario, since the GHG reductions resulting from the substitution of gasoline for hydro or nuclear power are significant. In Alberta, wind power is the cheaper method of GHG abatement because wind power is closer in price to the coal and natural gas dominated Alberta mixture, while offering significant environmental benefits. PHEVs represent a more expensive method of GHG abatement in Alberta, since substituting gasoline for expensive, GHG-intense electricity in a vehicle does less to reduce overall emissions. Results also indicate that PHEV charging should take place during off-peak hours, to take advantage of surplus baseload generation. PHEV adoption helps wind power in Ontario and British Columbia, as overnight charging reduces the amount of cheap, clean baseload power displaced by wind during these hours. In Alberta, wind power helps PHEVs by cleaning up the generation mixture and providing more environmental benefit from the substitution of gasoline with electricity.