This thesis work aims to develop electrochemical sensors for sub-ppb level detection of inorganic and organic pollutants in drinking water with environmentally benign materials and processes. While traditional laboratory-based methods such as mass spectroscopy, and chromatography have been used to analyze the concentration of contaminants in drinking water, miniaturized electrochemical sensors offer a compelling alternative to those methods, enabling rapid on-site cost-effective detection of low concentrations of pollutants. In this research, a set of three-electrode sensors was designed and fabricated on a flexible substrate using a screen-printing technique. Additionally, an in-situ electrochlorination process was implemented to create the reference electrode. These sensors were utilized to precisely detect lead ions and perfluorooctane sulfonate (PFOS) in drinking water. The first set of sensors was fabricated to measure the concentration of lead ions, a toxic inorganic pollutant, in potable water. The novelty of the proposed research lies in using non-toxic, biodegradable sodium alginate grafted with 2- acrylamido-2-methyl propane sulfonic acid (AMPS) and conductive fillers for trace-level lead ion detection in water. The principle of square wave anodic square wave stripping voltammetry (SWASV) was used to determine the trace level lead ion concentration. Employing a similar approach with a different material, a PFOS sensor was developed. Utilizing chitosan, one of the sustainable and biodegradable biopolymers found in crustacean shells, rapid parts-per-trillion (ppt) level PFOS detection by electrochemical impedance spectroscopy (EIS) was demonstrated. The proposed sensors made low-cost electrochemical detection of contaminants such as lead ions and PFOS possible with eco-friendly materials and processes.

In recent times, attention to the indoor plants in the houses has increased, which can be used to produce food or just for decoration and for health purposes. However, moving plants from their original place in nature to a closed place leads to negative effects due to changing environmental parameters around them. For instance, fluctuations in temperature, light, and soil moisture might affect indoor plant growth process. This work investigates the possibility of using the smart mobile and web applications to monitor remotely the most of changing environmental parameters around plants. These parameters can give the user the real-time information on air temperature and humidity, soil temperature and moisture, as well as amount of light. The Top-down method has been used to design a monitoring system to help the user keep informed of indoor climate changes. This system contains Raspberry and some sensors that are used in sensing various environmental conditions. It also includes the software component which defines services and actions to be taken on the data collected by sensing objects. The system is tested and evaluated in the indoor environment to prove the required concepts. The results indicated that web and mobile interfaces transfer data in real-time manner and send environmental information to the user. The data collected is visualized by different charts and figures to give a better understanding of the surrounding conditions in which the plant grows. It is concluded that the proposed system provides a user-friendly monitoring application to monitor the most indoor environmental parameters.

The humidity, temperature, wind speed/direction micro sensors can be manufactured individually, resulting in three individual substrates. The integration of the three sensors into a single substrate is a vital challenge to achieve an integrated intelligent sensor so called a multiple sensor. This requires the integration of process flows and is a major challenge because adequate sensor performance must be maintained. Polyimide was selected as a humidity sensing material for its compatibility with conventional integrated circuit fabrication technology, negligible temperature dependence and good resistance against contamination. Nickel was selected for the temperature and wind speed/direction sensor because of its useful temperature coefficient and the advantage of its cost. Since the known wet etchant for nickel requires hard-baked photoresist, a method which does not attack the polyimide while removing the photoresist must be developed. The method developed for etching nickel employs hard-bake-free photoresist. Other challenge was ensuring good thermal isolation for the wind speed/direction sensor fabricated on a silicon nitride layer preformed on top of a silicon wafer. Since silicon acts as a good heat sink, the silicon under the sensor was etched entirely away until the silicon nitride layer was reached. This structure achieved good thermal isolation resulting in small power consumption. This low power feature is essential for sensors deployed in fields where power access or replacement of power sources is restricted. This structure was compared with the structure created by polyimide plateau on a silicon nitride layer coated on a silicon substrate as a function of power consumption. Based on the examination of thermal isolation, the multiple sensor utilizing a MEMS technique was fabricated with a single-sided mask aligner. The characteristics of humidity sensors fabricated with polyimide were examined in detail with respect to variations of electrode structures, improvement of sensitivity, effect of process temperature, temperature and frequency dependence, and stability. The humidity sensor constructed with O2 plasma treated polyimide resulted an improvement in sensitivity and hysteresis. The investigation using XPS, FTIR and AFM concluded the chemical modification of polyimide played an important role in this improvement. The design, fabrication and results of a series of humidity sensors are quantified. There is always no unique packaging solution for sensors because of the application-specific nature of the sensors. This intelligent environmental monitoring system was designed to accommodate both an environmental sensor and its signal conditioning electronics circuitry (SICONEC) into a single package. The environmental sensors need direct exposure to the environment while SICONEC needs a sealed encapsulation to avoid environmental damage. A new style of packaging addressing these requirements was demonstrated using a hot embossing machine. The hot embossing machine was used to embed an integrated circuit (IC) in a bare die condition into a polycarbonate (PC) sheet. In this case, the IC was flipped down against the PC, which protects the front side of the IC from the environmental damages. In a test phase, a die containing operational amplifiers was embossed into the PC. A humidity sensor and surface mount resisters were placed on the same surface of the PC to test the validity of this new technique. Interconnection between the embossed die and the humidity sensor was established using bonding wires. Copper tracks were also used to ensure all electrical connections for the die, the humidity sensor and the resistors. The results clarified the method developed. Details of process methods, issues and further potential improvement are reported.

The introduction of the use of Tire Pressure Control Systems (TPCS) to improve the productivity of the Canadian trucking industry is gaining momentum. The imposition of seasonal load restrictions (SLR) on the thaw-weakened secondary roads interrupts the transportation of raw materials to processing facilities For the forestry industry in particular, this has very significant impacts on productivity and costs. FPInnovations-Feric Division (Feric) has investigated the potential for TPCS-equipped trucks to travel with full, legal loading during the SLR period without accelerating road wear and tear. The TPCS monitors and adjusts the inflation pressure of the trucks’ tires while driving and allows the operator to optimize the inflations for changes in loading, travel speed, or road quality encountered in the trip. This thesis describes an investigation to determine whether TPCS can be used to mitigate traffic generated damage to secondary roads and also reduce the need to implement load restrictions. The project involves a partnership with the Ontario Ministry of Transportation Ontario (MTO), Forest Engineering Research Institute of Canada (FERIC), Ontario Ministry of Natural Resources (MNR) and the Centre for Pavement and Transportation Technology (CPATT) located at the University of Waterloo. The thesis will describe the methodology, design, and instrumentation of the two test sites which are located in Dryden, Ontario and Chapleau, Ontario. In addition, repeated Portable Falling Weight Deflectometer (PFWD) testing is being carried out at these sites and the initial results of this examination and associated impacts of the environment and traffic on the road will be presented. This study also involves looking into the reliability of using the portable FWD, offering a lower cost alternative instead of the trailer mounted FWD to monitor pavement strength for the identification the SLR period. The use of innovative sensors and data collection techniques are proving to be very informative and are advancing pavement engineering knowledge. Moreover, the thesis is aimed at exploring the possibilities of achieving the current objectives of the government DOTs such as TPCS potential for addressing the timber industry in crisis, reduced road maintenance budgets, and global warming increasing road damage.

The introduction of the use of Tire Pressure Control Systems (TPCS) to improve the productivity of the Canadian trucking industry is gaining momentum. The imposition of seasonal load restrictions (SLR) on the thaw-weakened secondary roads interrupts the transportation of raw materials to processing facilities For the forestry industry in particular, this has very significant impacts on productivity and costs. FPInnovations-Feric Division (Feric) has investigated the potential for TPCS-equipped trucks to travel with full, legal loading during the SLR period without accelerating road wear and tear. The TPCS monitors and adjusts the inflation pressure of the trucks’ tires while driving and allows the operator to optimize the inflations for changes in loading, travel speed, or road quality encountered in the trip. This thesis describes an investigation to determine whether TPCS can be used to mitigate traffic generated damage to secondary roads and also reduce the need to implement load restrictions. The project involves a partnership with the Ontario Ministry of Transportation Ontario (MTO), Forest Engineering Research Institute of Canada (FERIC), Ontario Ministry of Natural Resources (MNR) and the Centre for Pavement and Transportation Technology (CPATT) located at the University of Waterloo. The thesis will describe the methodology, design, and instrumentation of the two test sites which are located in Dryden, Ontario and Chapleau, Ontario. In addition, repeated Portable Falling Weight Deflectometer (PFWD) testing is being carried out at these sites and the initial results of this examination and associated impacts of the environment and traffic on the road will be presented. This study also involves looking into the reliability of using the portable FWD, offering a lower cost alternative instead of the trailer mounted FWD to monitor pavement strength for the identification the SLR period. The use of innovative sensors and data collection techniques are proving to be very informative and are advancing pavement engineering knowledge. Moreover, the thesis is aimed at exploring the possibilities of achieving the current objectives of the government DOTs such as TPCS potential for addressing the timber industry in crisis, reduced road maintenance budgets, and global warming increasing road damage.

Submitted by Maria Medeiros (maria.dilva1@ufcg.edu.br) on 2018-10-10T14:25:54Z No. of bitstreams: 1 JOACI DOS SANTOS CERQUEIRA - TESE (PPGRN) 2018.pdf: 25053168 bytes, checksum: f171a30ed512369a6372b1d77a7bb854 (MD5) / Made available in DSpace on 2018-10-10T14:25:54Z (GMT). No. of bitstreams: 1 JOACI DOS SANTOS CERQUEIRA - TESE (PPGRN) 2018.pdf: 25053168 bytes, checksum: f171a30ed512369a6372b1d77a7bb854 (MD5) Previous issue date: 2018-02-23 / CNPq / Os poluentes atmosféricos das usinas termelétricas afetam negativamente a saúde humana, o solo, os corpos hídricos, as edificações, a flora e a fauna. Assim, essa forma de geração de energia elétrica, gera efluentes causadores de danos ao meio ambiente, trazendo impactos ambientais negativos. Neste sentido, o objetivo desse estudo foi avaliar os impactos ambientais causados pelo funcionamento de uma Usina Termelétrica localizada na região metropolitana de Campina Grande-PB. Através de um estudo de campo, de caráter exploratório foi empregado variadas metodologias para identificar as espécies da ornitofauna local, inventariar as espécies arbóreas e avaliar as trocas gasosas vegetais, além de utilizar de sensores ambientais pata determinar os níveis instantâneos dos compostos químicos CO2, CO, SO2, ruídos, temperatura do ar, umidade relativa do ar, temperatura de ponto de orvalho, velocidade do vento e luminescência vegetais, do entorno da Usina Termelétrica Energética Borborema S.A e de uma área amostral; e, através do software Aermod View, simular as concentrações das dispersões das fontes emissoras da Usina Termelétrica. Com isso, registrou-se vinte e nove espécies de aves, pertencentes a 21 famílias; e, para no inventário arbóreo, as principais espécies encontradas foram Combretum glaucocarpum, Croton sonderianus, Aspidosperma pyrifolium e Mimosa tenuiflora; quanto as análises das trocas gasosas realizadas pelo LCpro+, verificou-se que os valores máximos de transpiração foi registrado no ponto (P600), sendo a espécie Ziziphus joazeiro responsável pelo maior valor registrado; em relação ao uso dos sensores ambientais para monitorar a qualidade do ar, atestou-se ser uma ferramenta fundamental para verificar alterações na ambiência do entorno da Termelétrica Borborema S.A.; na modelagem com Aermod View, verificou-se que nas concentrações de NO2, os índices atingiram cerca de cinco vezes maior que o padrão primário estabelecido pelo CONAMA 03/90. Desta maneira, os resultados associados aos procedimentos metodológicos utilizados em conjunto, caracterizam-se como eficazes para avaliação e monitoramento de impactos ambientais para instalação e funcionamento de Termelétricas e demais indústrias poluidoras. / The air pollutants of thermoelectric power plants negatively affect human health, soil, water bodies, buildings, flora and fauna. Thus, this form of electric energy generation, generates effluents that cause damages to the environment, bringing negative environmental impacts. In this sense, the objective of this study was to evaluate the environmental impacts caused by the operation of a Thermoelectric Plant located in the metropolitan region of Campina Grande-PB. Through an exploratory field study, a variety of methodologies were used to identify the species of the local ornitofauna, to inventory the tree species and to evaluate the vegetal gas exchanges, besides using environmental sensors to determine the instantaneous levels of the chemical compounds CO2, CO, SO2, noise, air temperature, relative air humidity, dew point temperature, wind speed and plant luminescence, in the surroundings of Usina Termelétrica Energética Borborema S.A. and a sample area; and, through the Aermod View software, to simulate the dispersion concentrations of the sources emitting the Thermoelectric Plant. Thus, twenty-nine bird species belonging to 21 families were recorded; and, for the tree inventory, the main species found were Combretum glaucocarpum, Croton sonderianus, Aspidosperma pyrifolium and Mimosa tenuiflora; as well as the analyzes of the gas exchanges performed by LCpro +, it was verified that the maximum values of transpiration were recorded at the point (P600), and the Ziziphus joazeiro species was responsible for the highest recorded value; in relation to the use of environmental sensors to monitor air quality, was proved to be a fundamental tool to verify changes in the environment of the Borborema thermoelectric plant S.A.; in the modeling with Aermod View, it was verified that in the concentrations of NO2, the indexes reached about five times greater than the primary standard established by CONAMA 03/90. In this way, the results associated to the methodological procedures used together, are characterized as effective for evaluation and monitoring of environmental impacts for the installation and operation of Thermoelectric and other polluting industries.

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