Being able to accurately map forest carbon is a critical step in the global carbon cycle modeling and management process. This project is aimed at enhancing the current methodologies used for forest carbon mapping, and applying a method to account for any errors produced. By doing so, more accurate decisions can be made based on the knowledge gained from forest carbon maps; such as policy decisions on how to manage forests, or how to mitigate climate change. The use of remotely sensed images, in combination with Forest Inventory and Analysis (FIA) data, is one such way of doing this. This study compared three different methods; including linear regression, cosimulation, and up-scaled cosimulation to interpolate forest carbon based on a defined relationship between sample plots of national FIA data and satellite images. An uncertainty analysis was completed in an effort to quantify, and separate the different sources of error produced within a cosimulation mapping effort. The results indicated that the band ratio of TM4 / TM5 + TM4 / TM7 had the highest correlation coefficient, around 0.56, with the FIA forest carbon values. At a resolution of 90 m ×by 90 m, co-simulation predicted carbon values from about 14 Mg/ha, to 135 Mg/ha. The regression model, at the same resolution, estimated carbon values from about -17 Mg/ha, to 2,400 Mg/ha. Up-scaled cosimulation at a resolution of 990 m x× 990 m, predicted carbon values of ranging from 16 Mg/ha, to 133 Mg/ha. The uncertainty analysis was unable to produce any statistically significant results, with all R2 values below 0.1. These results showed that using a linear regression produced some impossible estimates, while cosimulation led to more realistic values. However, no conclusion can be made when comparing the methods based on the map validation techniques used. Although limited validation of the results was conducted, using both the FIA data and some independent sampling data; further work that focuses on validation is recommended.

Na presente dissertação foi desenvolvido um procedimento automático para a determinação de selênio em rações para animais doméstico digeridas em meio ácido. O método automatizado foi baseado no efeito catalítico do selênio(IV) na reação de sulfato de ferro amoniacal com EDTA em meio contendo NaNO3. O módulo de análise foi baseado no processo de multicomutação em fluxo. Tendo em vista que reação tem cinética lenta, o módulo de análise foi projetado com seis bobinas de reação acopladas em paralelo para permitir tempo de residência da zona de amostra em torno de cinco minutos, sem comprometer a freqüência de amostragem. Após a definição das variáveis de controle, amostras de rações para animais digeridas em meio de ácido nítrico/perclórico foram processadas. Os resultados referentes ao testes de adição de padrão apresentaram recuperação entre 95 e 109 %. Outras características importantes tais como desvio padrão relativo em torno de 2% (n = 8) e freqüência de amostragem de 60 determinações por hora foram observadas. / In this work it was developed an automatic procedure for the determination of selenium in ration for domestic animals digested in acidic medium. The automated method was based on the catalytic effect caused by selenium (IV) on the reaction of ammoniacal iron sulfate with EDTA in medium containing NaNO3. The analytical module was based on multicommuted flow process. Considering that the kinetic of reaction was slow, the analytical module was designed with six reaction coupled in parallel in order to allow that residence time of sample zone was increased up to 5 min without decrease of the analytical throughput. After definition of the system control variables, sample of animal ration mineralized in nitric/perchloric acid medium were processed. The results concerning to standard solution addition assays gave recoveries between the range of 95 % up to 109 %. Other profitable features such as a relative standard deviation of 2 % (n = 8) and an analytical throughput of 60 samples determination per hours were also achieved.

Na presente dissertação foi desenvolvido um procedimento automático para a determinação de selênio em rações para animais doméstico digeridas em meio ácido. O método automatizado foi baseado no efeito catalítico do selênio(IV) na reação de sulfato de ferro amoniacal com EDTA em meio contendo NaNO3. O módulo de análise foi baseado no processo de multicomutação em fluxo. Tendo em vista que reação tem cinética lenta, o módulo de análise foi projetado com seis bobinas de reação acopladas em paralelo para permitir tempo de residência da zona de amostra em torno de cinco minutos, sem comprometer a freqüência de amostragem. Após a definição das variáveis de controle, amostras de rações para animais digeridas em meio de ácido nítrico/perclórico foram processadas. Os resultados referentes ao testes de adição de padrão apresentaram recuperação entre 95 e 109 %. Outras características importantes tais como desvio padrão relativo em torno de 2% (n = 8) e freqüência de amostragem de 60 determinações por hora foram observadas. / In this work it was developed an automatic procedure for the determination of selenium in ration for domestic animals digested in acidic medium. The automated method was based on the catalytic effect caused by selenium (IV) on the reaction of ammoniacal iron sulfate with EDTA in medium containing NaNO3. The analytical module was based on multicommuted flow process. Considering that the kinetic of reaction was slow, the analytical module was designed with six reaction coupled in parallel in order to allow that residence time of sample zone was increased up to 5 min without decrease of the analytical throughput. After definition of the system control variables, sample of animal ration mineralized in nitric/perchloric acid medium were processed. The results concerning to standard solution addition assays gave recoveries between the range of 95 % up to 109 %. Other profitable features such as a relative standard deviation of 2 % (n = 8) and an analytical throughput of 60 samples determination per hours were also achieved.

The developments of immunoassay methods for the early stage diagnosis of tuberculosis (TB) are described. These went through two different routes, one through flow injection analysis (FIA), and the other using immunochromatography methodology. The design of a simple longwavelength fluorescence detector to serve the above purposes has also been described. The FIA immunoassay methods involve immobilising antibodies on to beads, either directly or through protein A based solid phases. The beads are then packed into a micro-column reactor for incorporation into the FIA system. In this case reactor-bound molecules are eluted from the system by a change of pH, thus limiting the available fluorophores to those that are reasonably fluorescent in acid solution. Sandwich (reagent excess) assays have been investigated. A couple of long wavelength (600-800) fluorophores have been studied. The bead injection option has also been investigated. The immunochromatographic method uses a lateral flow system and a sandwich (two-site) immunometric assay. Capture antibodies are immobilised on a coated membrane matrix at a pre-determined position and the antigen is analysed after binding to a fluorescence-labelled antibody. Both fluorescent latex preparations and conventional fluorescent labels have been used and compared. The strips are simply immersed in a small volume of sample to start the analysis. The chromatographic step is rapid and extremely simple. The fluorescence detector is fitted with a motor-driven sample holder to allow the length of the immunochromatographic strip to be scanned. The detector utilises a diode laser light source, optical filters in the emission beam and a miniaturised photomultiplier. It can be easily modified for the FIA, and can readily be adapted to operate from batteries, so is suitable for field use.

Made available in DSpace on 2014-06-12T23:14:19Z (GMT). No. of bitstreams: 2 arquivo6561_1.pdf: 896711 bytes, checksum: 53f117bb22137d029041d22020c91fd8 (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2011 / Instituto Federal de Educação, Ciência e Tecnologia de Pernambuco / É cada vez maior a preocupação das pessoas com o meio ambiente e sustentabilidade. O presente trabalho é dividido em dois capítulos. No primeiro capítulo a decomposição do detergente em pó para posterior determinação da concentração de fósforo em sua formulação é avaliada quando são utilizados autoclave e forno de micro-ondas. Para estabelecer as melhores condições experimentais foi realizado um planejamento fatorial 25 variando condições experimentais de digestão bem como os parâmetros de fluxo para determinação de fósforo. Após determinar a melhor condição foram realizados experimentos para avaliar o teor de fósforo em detergentes em pó comercializados no Recife. As melhores condições de digestão encontradas foram 0,2 mL da solução de ácido sulfúrico, potência utilizada no forno de micro-ondas de 500 W, tempo de digestão de 2 minutos e para o sistema em fluxo, a concentração de 16 mmol L-1 de molibdato. Estas condições proporcionam um menor custo de reagente quando comparado com o método de referência. Os resultados para determinação de fósforo no sistema em fluxo indicam, de acordo com o teste-t, que não existe diferença significativa entre a digestão em autoclave e em forno de micro-ondas, dentro de um limite de confiança de 95%. O ácido peracético (APA) é um sanitizante que desperta atenção pelo seu poder biocida e por não gerar subprodutos indesejáveis como os compostos orgânicos halogenados. No segundo capítulo foi desenvolvido um sistema de multicomutação em fluxo (MCFIA) para determinação de ácido peracético. O método foi baseado na reação da DDPD (uma forma metil substituída da N-dietil-p-fenilenodiamina) com o ácido peracético utilizando o kit comercial Vacu-vials® (CHEMetrics, Inc). Três minibombas solenóide foram utilizadas para inserir soluções de amostra, solução carregadora (água) e reagente (kit Vacu-vials). O produto da reação foi monitorado a 565 nm. Com as melhores condições experimentais, foi observada resposta linear entre 0,5 e 5,0 mg L-1 de APA (R = 0,9995); um desvio relativo de 4,0 % (n = 8) para a amostra de 3,0 mg L-1 APA; um limite de detecção de 0,10 mg L-1; frequencia analítica de 36 determinações por hora com consumo de reagente de 80 μL por determinação e volume de resíduo de 280 μL por determinação

The United States Forest Service (USFS) Forest Inventory and Analysis (FIA) program provides a diverse selection of data used to assess the status of the nation’s forested areas using sample locations dispersed throughout the country. Airborne, and more recently, terrestrial lidar (light detection and ranging) systems are capable of producing accurate measurements of individual tree dimensions and also possess the ability to characterize three-dimensional vertical forest structure. This study investigates the potential of airborne and terrestrial scanning lidar systems for modeling forest volume and aboveground biomass on FIA subplots in the Malheur National Forest, eastern Oregon. A methodology for the creation of five airborne lidar metric sets (four point cloud-based and one individual tree based) and four terrestrial lidar metric sets (three height-based and one distance-based) is presented. Metrics were compared to estimates of subplot aboveground biomass and gross volume derived from FIA data using national and regional allometric equations respectively. Simple linear regression models from the airborne lidar data accounted for 15 percent of the variability in subplot biomass and 14 percent of the variability in subplot volume, while multiple linear regression models increased these amounts to 29 percent and 25 percent, respectively. When subplot estimates of biophysical parameters were scaled to the plot-level and compared with plot-level lidar metrics, simple linear regression models were able to account for 60 percent of the variability in biomass and 71 percent of the variation in volume. Terrestrial lidar metrics produced moderate results with simple linear regression models accounting for 41 percent of the variability in biomass and 46 percent of the variability in volume, with multiple linear regression models accounting for 71 percent and 84 percent, respectively. Results show that: (1) larger plot sizes help to mitigate errors and produce better models; and (2) a combination of height-based and distance-based terrestrial lidar metrics has the potential to estimate biomass and volume on FIA subplots.

Actualment, és necessari disposar d'informació útil i en temps real per al desenvolupament sostenible en diversos camps. La monitorització és una eina eficaç per a la caracterització de processos industrials i mediambientals, i comprèn un conjunt de tasques aplicades amb la finalitat d'obtenir informació qualitativa i quantitativa de paràmetres indicadors d'un procés. Les tendències actuals en la monitorització són utilitzar tècniques analítiques i/o sistemes de transducció que subministrin informació ràpida, fiable i representativa sobre l'estat real del procés. Per això, cal apropar la instrumentació al procés i minimitzar la intervenció humana. Així doncs, els dispositius de mesura utilitzats han d'oferir selectivitat suficient, sensibilitat adequada, temps de resposta ràpid i llargs períodes operatius sense supervisió.El disseny d'analitzadors de procés basats en metodologies de flux continu i sensors electroquímics (potenciomètrics) com a detectors permetrien resoldre molts dels problemes existents derivats del mesurament directe en un procés complex i subministrarien informació de tipus químic en temps real. Aquests equips conjugarien les avantatges derivades de la integració del procediment analític que aporten els sensors químics potenciomètrics amb la simplificació en termes d'automatització, pretractament de mostra i funcionament autònom que aporten les metodologies de flux continu.La tesi presentada s'emmarca dintre de diferents projectes de desenvolupament i transferència tecnològica i estableix les bases d'aplicabilitat dels sensors químics potenciomètrics en termes de fiabilitat de la informació obtinguda i robustesa en llargs períodes de monitorització.Els resultats presentats han permès la monitorització d'un procés industrial de preparació d'isocianurat sòdic desenvolupant un sistema en flux que incorpora un ESI (elèctrode selectiu d'ions) de membrana amb portador mòbil carregat selectiu a monohidrogenisocianurat. D'altra banda, s'ha desenvolupat un analitzador automàtic de nitrat basat en la tècnica d'anàlisi per injecció en flux continu (FIA) i un dispositiu sensor selectiu a ió nitrat per a la determinació d'aquest paràmetre en l'etapa de nitrificació d'una planta pilot de tractament d'aigües residuals industrials. Per al mateix procés, s'ha desenvolupat un analitzador per a la monitorització de nitrit basat en una detecció colorimètrica de la reacció de Griess-Ilosvay. L'automatització del procediment s'ha dut a terme amb la tècnica FIA i integra una etapa de difusió gasosa per eliminar els problemes derivats de la mesura colorimètrica directa. Finalment, s'ha desenvolupat un sistema semiautomàtic d'anàlisi de fangs residuals per a la determinació indirecta de sulfur d'hidrogen. Aquest sistema integra una cel·la de pervaporació com a sistema d'extracció d'analits volàtils. Desprès de l'etapa de pervaporació, la determinació de l'ió sulfur es duu a terme de forma contínua mitjançant un elèctrode selectiu d'ions. / Nowadays, it is necessary to have useful information at real time for a sustainable development in different areas. Monitoring is a powerful tool for the industrial and environmental processes characterization and includes a set of tasks focused on the obtaining of qualitative and quantitative information of key process parameters. Monitoring approaches tend to use analytical techniques and/or transduction systems to afford feasible and real-time information about the process status. Therefore, it is necessary to situate the analysers in process stream and to minimize human intervention. Consequently, these devices have to provide enough selectivity, suitable sensitivity, short response time and to operate reliably over long periods of time without supervision.The process analysers based on flow continuous techniques and electrochemical sensors (potentiometric transduction) as detectors avoid most of the existing problems due to the direct measurements in complex processes and the obtaining of chemical information at real time. This instrumentation combines the advantage of the analytical procedure integration provided by chemical sensors and the simplicity in terms of automation, sample pre-treatment and unattended operation offered by continuous flow methodologies. The thesis presented is enclosed in different development and technological transfer projects and it establishes the applicability of potentiometric chemical sensors in terms of information reliability and robustness in long monitoring time.The results presented have allowed the monitoring of isocyanurate sodium manufacturing process by developing a flow continuous method which integrates an ISE (ion selective electrode) based on ion-exchanged carrier selective to monohidrogenisocyanurate. On the other hand, it has been developed an automatic analyser based on the flow injection analysis technique (FIA) and a chemical sensor selective to nitrate for the determination of this parameter in a nitrification stage from a pilot Waste Water Treatment Plant. For the same process, an automatic analyser for the nitrite monitoring based on the Griess-Ilosvay colorimetric reaction has been set up. The automation of the procedure has been carried out by FIA and it integrates a gas diffusion step to eliminate the problems due to the direct colorimetric method. Finally, it has been developed a semiautomatic analysis system for the indirect determination of hydrogen sulphide in sludge. This system integrates a pervaporation module to remove volatile analytes. After pervaporation, the detection of sulfide ion has been carried out continuously by means of an ion selective electrode.

In cooperation with the USDA Forest Service Southern Research Station, an algorithm has been developed to replace the current aerial-photography-derived FIA Phase 1 estimates of forest/non-forest with a Landsat Thematic Mapper-based forest area estimation. Corrected area estimates were obtained using a new hybrid classifier called Iterative Guided Spectral Class Rejection (IGSCR) for portions of three physiographic regions of Virginia. Corrected area estimates were also derived using the Landsat Thematic Mapper-based Multi-Resolution Land Characteristic Interagency Consortium (MRLC) cover maps. Both satellite-based corrected area estimates were tested against the traditional photo-based estimates. Forest area estimates were not significantly different (at the 95% level) between the traditional FIA, IGSCR, and MRLC methods, although the precision of the satellite-based estimates was lower. The estimated percent forest area and the standard error (respectively) of the estimates for each region and method are as follows; Coastal Plain- Phase 1 66.06% and 1.08%, IGSCR 68.88% and 2.93%, MRLC 69.84% and 3.08%. Piedmont- Phase 1 63.87% and 1.91%, IGSCR 65.52% and 3.50%, MRLC 59.19% and 3.83%. Ridge and Valley- Phase 1 69.74% and 1.22%, IGSCR 70.02%, and 2.43%, MRLC 70.53% and 2.52%. Map accuracies were not significantly different (at the 95% level) between the IGSCR method and the MRLC method. Overall accuracies ranged from 80% to 89% using FIA definitions of forest and non-forest land use. Given standardization of the image rectification process and training data properties, the IGSCR methodology is objective and repeatable across users, regions, and time and outperforms the MRLC for FIA applications. / Master of Science

Current carbon and bioenergy markets shifted the focus of typical forest attribute estimation from volume to biomass. We used multiple linear regression and the dataset collected as part of the National Scale Volume and Biomass modeling effort to develop biomass prediction models for Pinus taeda L., Pinus elliottii Engelm. var. elliottii, Pinus echinata Mill., and Pinus palustris Mill. In addition to utilizing traditional forest measurements such as diameter at breast height and total tree height, biomass was estimated as functions of volume, latitude, and longitude. We also evaluated the differences in wood density by geographic location for these species. The best results were obtained when models were fitted using the combined dataset and a log transformed model. Wood density estimates were improved by including latitude and longitude in the model. These findings will be useful to managers seeking improved biomass yield estimates and density by geographic regions.

A química limpa tem como principal objetivo o desenvolvimento e a implementação de processos e produtos químicos para reduzir ou eliminar o uso ou a geração de substâncias nocivas à saúde humana e ao meio ambiente. Neste trabalho, foram desenvolvidos procedimentos analíticos limpos para a determinação de nitrato e nitrito em águas naturais e para o tratamento dos resíduos gerados na determinação espectrofotométrica de nitrito e fenóis. Para tanto, foram exploradas as principais estratégias empregadas em química limpa: substituição dos reagentes tóxicos, minimização do consumo dos reagentes e dos resíduos gerados e tratamento desses resíduos. O procedimento analítico limpo para a determinação de nitrato em águas naturais foi baseado em medidas diretas no ultravioleta, após separação de nitrato dos interferentes utilizando um sistema de análises em fluxo com coluna de resina aniônica. O método desenvolvido emprega um único reagente (HClO4) em quantidades mínimas (18 µL/determinação) e permite a determinação de nitrato entre 0,50 e 25,0 mg L-1, sem interferência de ácido húmico, NO2-, PO43-, Cl-, SO42- e ferro(III) nas quantidades usuais em águas naturais. A freqüência de amostragem e o coeficiente de variação (n = 20) foram estimados em 17 determinações h-1 e 0,7%, respectivamente. Os resultados obtidos para amostras de águas de diferentes procedências foram concordantes com o método de referência (redução a nitrito por limalhas de cádmio cobreado seguida por reação de diazo-acoplamento) a nível de confiança de 95%. O tratamento do resíduo gerado na determinação de nitrito, empregando irradiação (UV) na presença do reagente de Fenton (80 mmol/L H2O2 e 1 mmol/L Fe2+), promoveu completa descoloração do resíduo com diminuição de ca. 87% na concentração de carbono orgânico total. A fotodegradação também foi aplicada no tratamento do resíduo gerado na determinação de fenóis totais com 4-aminoantipirina. A degradação ocorreu na presença de H2O2 e irradiação (UV). A completa supressão da absorção de radiação pela 4-aminoantipirina foi observada após 30 min de recirculação da solução no foto-reator, à vazão de 4 mL/min. O procedimento analítico para a determinação de nitrito foi baseado em sistema de análises em fluxo com multicomutação empregando mini-bombas solenóides para o gerenciamento das soluções. O sistema foi acoplado a um foto-reator para a degradação em linha dos resíduos gerados. O método desenvolvido minimiza as quantidades de reagentes (0,6 mg sulfanilamida e 0,03 mg N-naftil-etilenodiamina por determinação) e permite a determinação de nitrito entre 0,10 e 1,00 mg L-1 (r = 0,998) com sensibilidade comparável à alcançada no procedimento com adição contínua de reagentes. O limite de detecção (99,7% de confiança), coeficiente de variação (n = 20) e freqüência de amostragem foram estimados em 17 µg L-1, 2,6% e 80 determinações h-1, respectivamente. / Green chemistry has as principal objective the development and implementation of chemical processes and products to minimize or eliminate the use or generation of harmful substances to the human health and the environment. In this work, clean analytical procedures for determination of nitrate and nitrite in natural waters and for the treatment of wastes generated in the spectrophotometric determination of nitrite and phenol were developed. The principal strategies employed in green chemistry were explored to achieve these goals: replacement of the toxic reagents, minimization of reagent consumption and waste generation and waste treatment. The clean analytical procedure for nitrate determination in natural waters was based on the direct spectrophotometric measurement in the ultraviolet, after separation of nitrate from interfering species in a flow-injection system with an anion-exchange resin. The developed method employ only one reagent (HClO4) in minimum amount (18 µL/determination) and can be applied for nitrate determination within 0.50 and 25.0 mg L-1, without interference of humic acid, NO2-, PO43-, Cl-, SO42- and iron(III) in concentrations typically found in natural waters. The sampling rate and the coefficient of variation (n = 20) were estimated as 17 determinations per hour and 0.7%, respectively. Results obtained for natural water samples of different origin were in agreement with the reference method (reduction to nitrite by copperized cadmium filings followed by a diazo-coupling reaction) at the 95% confidence level. The treatment of the waste generated in nitrite determination employing UV irradiation in the presence of Fenton reagent (80 mmol/L H2O2 and 1 mmol/L Fe2+) caused the complete discoloration of the waste and reduced the total organic carbon concentration in 87%. The photodegradation was also applied for the treatment of the waste generated in the determination of total phenols with 4-aminoantipyrine. The degradation occurred in the presence of H2O2 and UV irradiation. Radiation absorption by 4-aminoantipyrine was completely suppressed after 30 min of treatment of solution in the recirculation mode at 4mL/min. The analytical procedure for nitrite determination was based on a flow system with multicommutation employing solenoid micro-pumps for the solution handling. The developed method minimizes the reagent amounts (0.6 mg sulfanilamide and 0.03 mg N-(1-Naphthyl)-ethylene-diamine per determination) and can be applied for nitrite determination within 0.10 and 1.00 mg L-1 (r = 0.998) with sensitivity comparable to the achieved in the procedure with continuous reagent addition. The detection limit (99.7% of confidence), coefficient of variation (n = 20) and sampling rate were estimated as 17 µg L-1, 2.6% and 80 determinations per hour, respectively.