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Aplica??o da ozoniza??o e de processos oxidativos avan?ados na degrada??o dos f?rmacos paracetamol e dipirona presentes em efluentes aquosos simulados / Application of the ozonation and advanced oxidation processes on the degradation of the drugs Acetaminophen and Dipyrone present in simulated aqueous wastewatersRosado, Francisca Gabriela Lopes 15 December 2014 (has links)
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Previous issue date: 2014 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (Capes) / Funda??o de Amparo ? Pesquisa do estado de Minas Gerais (FAPEMIG) / A oxida??o de efluentes sint?ticos contendo os f?rmacos paracetamol (PCT) e dipirona (DPN), ambos analg?sicos largamente utilizados por humanos e animais foi conduzida pelos processos O3, O3/UV, H2O2/UV e H2O2/UV/O3 via rea??o direta (oz?nio molecular), indireta (radical hidroxila) e mista (O3/HO?) manipulando-se o pH do meio reacional. Essas subst?ncias tem grande resist?ncia aos processos convencionais de tratamento de efluentes e, assim buscam-se ferramentas mais eficientes para a degrada??o desses f?rmacos. A remo??o dos f?rmacos PCT e DPN nas amostras tratadas com os diferentes POA foi monitorada utilizando a t?cnica cromatografia l?quida de alta efici?ncia (HPLC). A quantidade total de compostos arom?ticos e o grau de mineraliza??o da mat?ria org?nica dissolvida foram avaliados por meio dos par?metros UV (254 nm), Demanda Qu?mica de Oxig?nio (DQO) e de Carbono Org?nico Total (COT). Al?m disso, a susceptibilidade a biodegradabilidade foi avaliada por meio da raz?o da DQO/COT. Os resultados experimentais mostraram que o tempo gasto para a degrada??o depende da natureza do f?rmaco, bem como do pH e do tipo de processo oxidativo. Verificou-se uma elevada percentagem de remo??o (95%) e um percentual moderado de mineraliza??o (35%) para os estudos utilizando os processos O3 (pH 12) e O3/UV. De um modo geral, verificou-se um aumento da biodegradabilidade das amostras tratadas para os diferentes tratamentos oxidativos. No caso dos processos H2O2/UV e H2O2/UV/O3 a remo??o dos f?rmacos foi alta, especialmente no caso do processo H2O2/ UV/O3 onde ap?s 45 min e dose de 200 ppm de per?xido obteve-se ?88% de remo??o dos f?rmacos. No caso do processo H2O2(800ppm)/O3/UV e para o f?rmaco PCT, verificou-se percentagens de remo??o de DQO e COT de 77% e 42%, respectivamente. J? para o f?rmaco DPN, os valores correspondentes obtidos foram de 70% e 68%, respectivamente. Analisando os resultados observou-se que a remo??o da DQO e do COT foi maior para os processos processo H2O2/UV/O3. Por outro lado, a maior remo??o das subst?ncias parentais (PCT e DPN) foi obtida utilizando o processo O3 (pH 12). A partir dos valores das constantes de velocidade em fun??o do pH estimou-se a contribui??o dos processos de oxida??o por via direta e indireta. De um modo geral, o estudo revelou que o uso dos presentes POA e/ou ozoniza??o pode constituir um processo de tratamento alternativo vi?vel para a remo??o/degrada??o dos f?rmacos PCT e DPN presente em ?guas contaminadas. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Qu?mica, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2014. / ABSTRACT
The oxidation of synthetic wastewaters containing the drugs Acetaminophen (PCT) and Dipyrone (DPN), which are analgesics of widespread use by the human being and animals, was carried out by means of the O3, O3/UV, H2O2/UV e H2O2/UV/O3 oxidative processes. The ?direct? oxidation process was promoted by action of the O3 (acidic solutions) while in the case of the ?indirect? processes the application of the Advanced Oxidation Processes (AOPs) has permitted the use of the hydroxyl radical (HO?) as the major oxidant. These substances are recalcitrant towards the conventional wastewater treatments and, therefore, the search for an efficient treatment for these effluents is of current interest. The removal of PCT and DPN in the treated samples using the different AOPs was monitored using the high performance liquid chromatography (HPLC) technique. The total amount of aromatics and the degree of mineralization of the dissolved organic matter were evaluated by means of the UV(254 nm) technique and the Chemical Oxygen Demand (COD) and Total Organic Carbon (COT) methods, respectively. In addition, biodegradability susceptibility was evaluated by means of the COD/TOC ratio. The experimental findings showed that the time spent for degradation depends on the nature of the drug, as well as on the pH and the type of the oxidative process. It was verified for the studies using the O3(pH 12) and O3/UV processes a high percentage of removal (95%) and a moderate percentage of mineralization (35%). On the whole, it was verified an increase in the biodegradability of the treated samples for the different oxidative treatments. In the case of the H2O2/UV and H2O2/UV/O3 processes the removal of PCT and DPN was high, especially in the case of the H2O2/UV/O3 where after 45 min and by using a peroxide dosage of 200 ppm a percentage of removal of ?88% was obtained. In the case of the H2O2(800ppm)/UV/O3 process and for PCT, it was verified percentages of removal for COD and COT of 77% and 42%, respectively. Accordingly, the corresponding values obtained for DPN were 70% and 68%, respectively. As a rule, the removal of COD and COT was higher for the H2O2/UV/O3 process. On the contrary, a higher removal (e.g., HPLC) of the parental substances (PCT and DPN) was obtained using the O3 (pH 12) process. In the case of the ozonation the contribution of the direct and indirect oxidation processes was evaluated from the values of the pseudo first-order rate constants obtained in the acidic and alkaline conditions. On the whole, the current study has revealed that the use of the present AOPs and/or ozonation can constitute a viable alternative treatment process for the removal/degradation of the PCT and DPN drugs present in contaminated waters.
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Elimina??o segura de arquivos em mem?ria n?o-vol?til / Secure file deletion in non volatile memoryWeber, Julia Silva 21 March 2017 (has links)
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Previous issue date: 2017-03-21 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / The advent of the Internet of Things (IoT) and the popularization of mobile devices with non-volatile memory brings new challenges regarding the removal of files. Techniques traditionally employed in magnetic media are not effective when applied to non-volatile memories, such as flash memory. Because of the peculiar characteristics of this type of memory, notably the existence of a Flash Translation Layer (FTL), operating systems only manage logical blocks, and no longer have direct control of the physical blocks of a flash memory. Consequently, new methods of safe removal have been developed, which employ Zero Override, Block Erase, and Cryptographic Erase techniques.
This work analyzes these methods, compares their operations and proposes a new method, with better performance than those described in the literature. The proposed method is a hybrid method, which combines overwriting and deletion operations to obtain a balanced use of these operations, avoid unnecessary deletion of unused blocks and reduce premature memory wear. To verify the efficiency of the proposed method and of the other methods, a simulator was developed to exercise the removal of files in several experiments. / O advento da Internet das Coisas (IoT) e a populariza??o de dispositivos m?veis com mem?ria n?o-vol?til traz novos desafios quanto a remo??o de arquivos. T?cnicas tradicionalmente empregadas em meios magn?ticos n?o s?o efetivas quando aplicadas para mem?rias n?o vol?teis, como a mem?ria flash. Devido ?s caracter?sticas peculiares deste tipo de mem?ria, notadamente a exist?ncia de uma Camada de Tradu??o da Flash (FTL), sistemas operacionais somente gerenciam blocos l?gicos, e n?o tem mais controle direto dos blocos f?sicos de uma mem?ria flash. Consequentemente, novos m?todos de remo??o segura foram desenvolvidos, que empregam opera??es de Sobrescrita com Zeros, de Apagamento de Blocos e t?cnicas de Apagamento Criptogr?fico.
Este trabalho analisa estes m?todos, compara suas opera??es e prop?e um novo m?todo, com melhor desempenho que os descritos na literatura. O m?todo proposto ? um m?todo h?brido, que combina de forma equilibrada opera??es de sobrescrita e apagamento, para evitar o apagamento desnecess?rio de blocos ainda n?o utilizados e reduzir o desgaste prematuro da mem?ria. Para verificar a efici?ncia do m?todo proposto e dos demais m?todos, foi desenvolvido um simulador para exercitar a remo??o de arquivos em diversos experimentos.
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Novos adsorventes para aplica??o na remo??o de enxofre de combust?veis / Application of new adsorbents in sulfur removal from fuelsOliveira, Katherine Carrilho de 04 February 2015 (has links)
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Previous issue date: 2015-02-04 / Atualmente o mercado exige derivados de petr?leo cada vez mais puros e, com isso, surge a
necessidade de novos m?todos para obten??o desses produtos que sejam mais eficientes e
economicamente vi?veis. Considerando a remo??o do enxofre do diesel, a maioria das
refinarias utiliza o processo de hidrogena??o catal?tica, a hidrodessulfuriza??o. Esses
processos s?o de elevado conte?do energ?tico e alto custo de produ??o, al?m de baixa
efici?ncia na remo??o do enxofre a baixas concentra??es (abaixo de 500 ppm). A adsor??o
apresenta-se como uma alternativa eficiente e economicamente vi?vel em rela??o ?s t?cnicas
atualmente utilizadas. Com isso, o objetivo principal deste trabalho ? desenvolver e otimizar a
obten??o de novos adsorventes a base de diatomita, modificados com microemuls?es de dois
tensoativos n?o i?nicos, agregando efici?ncia ao material, visando a sua aplica??o na remo??o
do enxofre presente no diesel comercial. Para a modifica??o da diatomita, variou-se: os
pontos de microemuls?o para cada tensoativo (RNX 95 e UNTL 90), a fase aquosa da
microemuls?o atrav?s da utiliza??o ou n?o de sais (CaCl2 e BaCl2) , o tempo de contato
durante a modifica??o e a forma de contato. Foram realizadas an?lises de microscopia
eletr?nica de varredura, difra??o de raios X, fluoresc?ncia de raios X, termogravimetria e
adsor??o de N2 (BET) para a caracteriza??o dos novos materiais obtidos. No estudo da
capacidade de adsor??o dos materiais obtidos, foi realizada uma modelagem estat?stica para
avaliar a influ?ncia da concentra??o do sal na fase aquosa (20 ppm a 1500 ppm), da
temperatura do banho finito (25 a 60?C) e da concentra??o de enxofre do diesel. Observou-se
que a temperatura e a concentra??o de enxofre (300 a 1100 ppm) foram os par?metros mais
significativos, no qual aumentando-se seus valores aumenta-se a capacidade da argila
modificada de adsorver o enxofre presente no diesel. A capacidade de adsor??o aumentou de
0,43 mg/g para 1,34 mg/g com a otimiza??o do ponto de microemuls?o e com a adi??o de
sais. / Currently the market requires increasingly pure oil derivatives and, with that, comes the need
for new methods for obtaining those products that are more efficient and economically viable.
Considering the removal of sulfur from diesel, most refineries uses catalytic hydrogenation
process, the hydrodesulfurization. These processes needs high energy content and high cost of
production and has low efficiency in removing sulfur at low concentrations (below 500 ppm).
The adsorption presents itself as an efficient and economically viable alternative in relation to
the techniques currently used. With that, the main purpose of this work is to develop and
optimize the obtaining of new adsorbents based on diatomite, modified with two non ionic
surfactants microemulsions, adding efficiency to the material, to its application on removal of
sulfur present in commercial diesel. Analyses were undertaken of scanning electron
microscopy (SEM), x-ray diffraction (XRD), x-ray fluorescence (XRF), thermogravimetry
(TG) and N2 adsorption (BET) for characterization of new materials obtained. The variables
used for diatomite modification were: microemulsion points for each surfactant (RNX 95 and
UNTL 90), microemulsion aqueous phase through the use or non-use of salts (CaCl2 and
BaCl2), the contact time during the modification and the contact form. The study of
adsorption capacity of materials obtained was performed using a statistical modeling to
evaluate the influence of salt concentration in the aqueous phase (20 ppm to 1500 ppm), finite
bath temperature (25 to 60? C) and the concentration of sulphur in diesel. It was observed that
the temperature and the concentration of sulphur (300 to 1100 ppm) were the most significant
parameters, in which increasing their values increase the ability of modified clay to adsorb the
sulphur in diesel fuel. Adsorption capacity increased from 0.43 to mg/g 1.34 mg/g with
microemulsion point optimization and with the addition of salts.
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Remo??o de corantes utilizando tensoativos: extra??o por ponto de nuvem e flocula??o i?nicaMelo, Ricardo Paulo Fonseca 23 April 2015 (has links)
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Previous issue date: 2015-04-23 / O setor t?xtil ? um dos principais respons?veis pela gera??o de efluentes
industriais devido, principalmente, aos grandes volumes de ?gua, que apresentam
elevado teor de carga org?nica. Neste, observa-se a presen?a de corantes, tensoativos,
amido, alco?is, ?cido ac?tico e outros constituintes, provenientes das v?rias etapas de
processamento do material t?xtil. Diante disto, o tratamento destes efluentes ?
necess?rio antes de lan??-los nos corpos de ?gua, pois podem causar altera??es f?sicoqu?micas
desastrosas para o meio ambiente. Os tensoativos s?o subst?ncias muito
utilizadas nos processos de separa??o e, neste trabalho, foram utilizados no tratamento
de efluentes t?xteis, aplicando a extra??o por ponto de nuvem e a extra??o por
flocula??o i?nica. Na extra??o de corante reativo por ponto de nuvem foi utilizado o
tensoativo nonilfenol, com grau de etoxila??o 9,5. A avalia??o do processo foi
realizada em termos da temperatura, concentra??o de tensoativo e de corante. Neste
processo, a remo??o de corante alcan?ou 91%. A flocula??o i?nica ocorre devido ?
presen?a de c?lcio, que reage com tensoativo ani?nico e forma tensoativos insol?veis,
capazes de atrair a mat?ria org?nica atrav?s da adsor??o. Neste trabalho, a flocula??o
i?nica, utilizando sab?o base, foi aplicada ao tratamento de efluente sint?tico contendo
corantes pertencentes a tr?s classes: os diretos, reativos e dispersos. A avalia??o do
processo foi realizada pela influ?ncia dos seguintes par?metros: concentra??o de
tensoativo e de eletr?litos, velocidade de agita??o, tempo de repouso, temperatura e
pH. A flocula??o do tensoativo foi realizada de dois modos: formando o floco no
pr?prio efluente e formando o floco antes de mistur?-lo ao efluente. A remo??o do
corante direto e reativo, quando o floco ? formado dentro do efluente t?xtil, foi de 97%
e 87%, respectivamente. No caso em que o floco ? formado antes de adicion?-lo ao
efluente a remo??o de corante direto e disperso alcan?ou 92% e 87%, respectivamente.
Estes resultados mostram que os processos avaliados foram eficientes para remo??o de
corantes em efluentes t?xteis. / The textile sector is one of the main contributors to the generation of
industrial wastewaters due to the use of large volumes of water, which has a high
organic load content. In these, it is observed to the presence of dyes, surfactants, starch,
alcohols, acetic acid and other constituents, from the various processing steps of the
textiles. Hence, the treatment of textile wastewater becomes fundamental before
releasing it into water bodies, where they can cause disastrous physical-chemical
changes for the environment. Surfactants are substances widely used in separation
processes and their use for treating textile wastewaters was evaluated in this research
by applying the cloud point extraction and the ionic flocculation. In the cloud point
extraction was used as surfactant nonylphenol with 9.5 ethoxylation degree to remove
reactive dye. The process evaluation was performed in terms of temperature, surfactant
and dye concentrations. The dye removal reached 91%. The ionic flocculation occurs
due to the presence of calcium, which reacts with anionic surfactant to form insoluble
surfactants capable of attracting the organic matter by adsorption. In this work the ionic
flocculation using base soap was applied to the treatment of synthetic wastewater
containing dyes belonging to three classes: direct, reactive, and disperse. It was
evaluated by the influence of the following parameters: surfactant and electrolyte
concentrations, stirring speed, equilibrium time, temperature, and pH. The flocculation
of the surfactant was carried out in two ways: forming the floc in the effluent itself and
forming the floc before mixing it to the effluent. Removal of reactive and direct dye,
when the floc is formed into textile effluent was 97% and 87%, respectively. In the
case where the floc is formed prior to adding it to the effluent, the removal to direct and
disperse dye reached 92% and 87%, respectively. These results show the efficience of
the evaluated processes for dye removal from textile wastewaters.
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S?ntese e caracteriza??o do comp?sito ferro zero-valente nanoparticulado/carv?o ativado granulado (nFZV-CAG) e sua aplica??o para remo??o do f?rmaco nimesulida pelos processos adsor??o/redu??o e ozoniza??o catal?tica heterog?neaOliveira, Fernanda Gandra de 13 September 2016 (has links)
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Previous issue date: 2016 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Funda??o de Amparo ? Pesquisa do Estado de Minas Gerais (FAPEMIG) / O comp?sito nFZV-CAG foi empregado para a ozoniza??o catal?tica heterog?nea da NMS em
meio aquoso. O oz?nio foi gerado por uma central geradora de oz?nio IPABRAS, alimentada
com ar. Foram avaliados diferentes processos catal?ticos como O3, CAG, O3-CAG, O3-nFZV-
CAG, e a varia??o da concentra??o das nFZV para remo??o da NMS. Os resultados mostraram
que a combina??o do O3-nFZV-CAG foi muito eficiente levando ? mineraliza??o de
aproximadamente 70% da NMS em 120 min de rea??o. Tal efici?ncia pode estar atribu?da ao
processo de eletr?lise, em que o Fe0
origina Fe2+
levando ? produ??o do radical hidroxila que ?
altamente oxidante, levando a destrui??o do contaminante. As rea??es seguiram a cin?tica
pseudo-primeira ordem para remo??o do f?rmaco. Ap?s realizada a coleta as amostras foram
submetidas a an?lise qu?mica, empregando-se as t?cnicas de espectrofotometria de UV-Vis,
cromatografia l?quida de alta efici?ncia (CLAE) e a determina??o da demanda qu?mica de oxig?nio
(DQO) tamb?m foi realizada. / As nanopart?culas de FZV imobilizadas sobre a superf?cie do carv?o ativado (nFZV-CAG)
foram sintetizadas e caracterizadas para remo??o do f?rmaco Nimesulida (NMS) em sistemas
aquosos. Os estudos foram realizados em bateladas com agita??o de 250 rpm durante 120
minutos, onde foram avaliadas a efici?ncia, concentra??o (20, 25 e 30% do comp?sito) e
diferentes dosagens (0,1 a 10g) de nFZV-CAG. Os resultados mostraram que a dosagem de 10
g de 20%nFZV-CAG removeu cerca de 80% da NMS 50 mg L-1
em apenas 30 minutos de
rea??o, e atingindo 100% em 120 minutos. Foi observada ainda uma remo??o de 80% da DQO
ao final da rea??o. As velocidades de rea??o aumentaram na medida em que foram aumentadas
as dosagens do comp?sito, o que seria esperado. Por?m, com o aumento da concentra??o (%)
de nFZV n?o houve aumento na velocidade das rea??es. As rea??es seguiram uma cin?tica de
pseudo-primeira ordem em rela??o ? remo??o da NMS. Ap?s realizada a coleta, as amostras
foram submetidas a an?lise qu?mica, empregando-se as t?cnicas de espectrofotometria de UV-
VIS, cromatografia l?quida de alta efici?ncia (CLAE) e a determina??o da demanda qu?mica de
oxig?nio (DQO) tamb?m foi realizada. Para caracteriza??o do comp?sito foram empregadas as
t?cnicas Microscopia Eletr?nica de Varredura acoplada ? Espectrometria de Energia Dispersiva
de Raios-X (MEV-EDS), que mostraram claramente a presen?a da nanopart?culas sobre a
superf?cie do carv?o, e analise de superf?cie do nFZV-CAG e do CAG tamb?m foram
realizadas. / Disserta??o (Mestrado) ? Programa de P?s-Gradua??o em Qu?mica, Universidade Federal dos Vales do Jequitinhonha e Mucuri, 2016. / The FZV nanoparticles immobilized onto the surface of the activated charcoal (nFZV-CAG)
were synthesized and characterized for the removal of the pharmaceutical Nimesulide (NMS)
in aqueous systems. The studies were performed in batch mode with stirring speeds of 250 rpm
during 120 minutes, so that it was possible to evaluate efficiency, concentration (20, 25 and
30% of the composite) and different dosages (0,1 to 10g) of nFZV-CAG. The results showed
that the dosage of 10g of 20%nFZV-CAG removed approximately 80% of NMS 50 mg L-1
in
just 30 minutes of reaction, and reaching 100% in 120 minutes. It was still observed a removal
of 80% of the COD (Chemical Oxygen Demand) at the end of the reaction. The reaction rates
increased with the dosage of the composite, which was expected. Though, increasing the
concentration (%) of nFZV did not result in higher reaction rates. The reactions followed a
pseudo-first order kinetics for the removal of NMS. After the samples were collected, they were
submitted to chemical analysis, employing the techniques of UV-VIS spectroscopy, high
performance liquid chromatography (HPLC) and chemical oxygen demand (COD). In order to
characterize the composite, the following techniques were used: Scanning Electron Microscopy
(SEM) coupled with Energy Dispersive x-Ray spectroscopy (EDS), which showed clearly the
presence of nanoparticles onto the charcoal surface. Analysis of the surface of nFZV-CAG were
also performed. / The composite nFZV-CAG was used for the catalytic ozonation of NMS in aqueous media. The
ozone was generated by an ozone generator IPABRAS, fuelled with air. Different catalytic
processes were evaluated such as O3, CAG, O3-CAG, O3-nFZV-CAG, and the variation of the
nFZV concentration for the removal of NMS. The results showed that the combination of O3-
nFZV-CAG was very efficient, leading to the mineralization of approximately 70% of NMS in
120 minutes of reaction. Such efficiency can be attributed to the electrolysis process, in which
the Fe0
generates Fe2+
which generates hydroxyl radicals that are highly oxidant, leading to the
destruction of the contaminant. The reactions followed the pseudo-first order kinetics for the
removal of the pharmaceutical. After the samples were collected, they were submitted to
chemical analysis such as, UV-VIS spectroscopy, high performance liquid chromatography
(HPLC) and chemical oxygen demand (COD).
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M?todo de avalia??o de algoritmos de detec??o e remo??o de sombra em imagens a?reasDoth, Ricardo Vinicius 27 March 2018 (has links)
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Previous issue date: 2018-03-27 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior - CAPES / Wide Area Motion Imagery (WAMI) systems acquire large area aerial images in real
time to provide accurate situational awareness information from a region (BLASCH et
al., 2014). This system is applied for urban aerial monitoring. Unfavorable environmental
conditions, such as shadow regions, are factors that increase system complexity by
compromising the effectiveness of tracking algorithms and human visual interpretation
(PORTER; FRASER; HUSH, 2010). Several techniques of shadow removal in aerial images
have been developed, however due to the characteristics of the shadow and aerial
image, a specific method to evaluate and compare the removal is unknown. The main
objective of this study is to develop a method to evaluate shadow removal algorithms in
aerial images acquired by the WAMI system. This work proposes a radiometric approach
modifying the illumination in a controlled environment, simulating an aerial scene, acquiring
images with and without the presence of shadows. The image with shadows is
processed by the evaluated shadow removal algorithm, with the ideal output being the
shadow free image. Shadow detection is evaluated using the confusion matrix concept.
Shadow removal is evaluated using the structural similarity index (SSIM). As a result the
reduced scale aerial scene model is presented to generate shadow and freeshadow images
and the evaluation of 3 shadow removal methods using the data sets of images obtained
from the scale model applying the methodology developed. / Sistemas WAMI (Wide Area Motion Imagery) adquirem imagens a?reas de grandes ?reas
em tempo real para prover informa??es precisas de uma determinada regi?o (BLASCH et
al., 2014). Este sistema ? aplicado para monitoramento a?reo urbano. Condi??es ambientais
desfavor?veis, como ?reas sombreadas, s?o fatores que aumentam a complexidade do
sistema comprometendo a efic?cia de algoritmos de rastreamento e a interpreta??o visual
humana (PORTER; FRASER; HUSH, 2010). Diversas t?cnicas de remo??o de sombra em
imagens a?reas foram desenvolvidas, no entanto devido ?s caracter?sticas da sombra e da
imagem a?rea ? desconhecido um m?todo espec?fico para avaliar e comparar a remo??o de
sombras em imagens a?reas. O objetivo principal deste estudo ? desenvolver um m?todo
para avaliar algoritmos de remo??o de sombra em imagens a?reas adquiridas pelo sistema
WAMI. Este trabalho prop?e uma abordagem radiom?trica modificando a ilumina??o em
um ambiente controlado, simulando uma cena a?rea, adquirindo imagens com e sem sombras.
A imagem com sombra ? processada pelo algoritmo de remo??o de sombra avaliado,
sendo a imagem sem sombra o resultado ideal a ser alcan?ado. A detec??o de sombra ?
avaliada utilizando o conceito de matriz de confus?o (error matrix). A remo??o de sombra
? avaliada utilizando o ?ndice de similaridade estrutural entre duas imagens (SSIM).
Foram desenvolvidos o modelo de cena a?rea em escala reduzida para gerar imagens com
e sem sombra e a avalia??o de 3 m?todos de remo??o de sombras utilizando os data sets
de imagens obtidas do modelo em escala aplicando a metodologia descrita.
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Avalia??o da remo??o de hidrocarbonetos arom?ticos (BTEX) em ?guas utilizando materiais nanoestruturados do tipo Ti-MCM-41Morais, Lidiane Alves de 30 January 2012 (has links)
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Previous issue date: 2012-01-30 / Volatile Organic Compounds are pollutants coming mainly from activities that use fossil fuels. Within this class are the BTEX (benzene, toluene, ethylbenzene and xylenes) compounds that are considered hazardous. Among the various existing techniques for degradation of pollutants, there is advanced oxidation using H2O2 generating hidoxil radical ( OH). In this work, the mesoporous material of MCM-41 was synthesized by hydrothermal
method and then was used as support, the impregnation of titanium by the method of synthesis with excess solvent to obtain the catalyst Ti-MCM-41. The catalyst was used in the
reaction catalyzed removal of BTEX in water using H2O2 as oxidant. The materials were characterized by: XRD, TG/DTG, FTIR, nitrogen adsorption-desorption and FRX-EDX, in
order to verify the method of impregnation of the mesoporous titanium support was effective. Catalytic tests were carried out in reactors of 20 mL containing BTEX (100.0 μg/L), H2O2
(2.0 M) and Ti-MCM-41 (2.0 g/L) in acid medium. The reaction occurred for 5 h at 60 ?C and analysis were performed by gas chromatography with photoionization detector and static
headspace sampler. The characterizations have proven the effectiveness of the synthesis method used and the incorporation of titanium lt in the support. The catalytic tests showed satisfactory results with conversion of more than 95 % for the studied compounds, where the catalyst 48% Ti-MCM-41 showed a higher removal efficiency of the compounds under study / Os Compostos Org?nicos Vol?teis s?o poluentes oriundos, principalmente, de atividades que utilizam combust?veis fosseis. Dentro desta classe encontram-se os BTEX (benzeno, tolueno, etilbenzeno e xilenos) que s?o compostos considerados perigosos. Dentre as varias t?cnicas existentes para degrada??o de poluentes, destaca-se a oxida??o avan?ada utilizando H2O2 para gera??o do radical hidoxil ( OH). Neste trabalho, o material mesoporoso do tipo MCM-41 foi sintetizado atrav?s do m?todo hidrot?rmica e em seguida foi utilizado como suporte, na impregna??o de tit?nio pelo m?todo p?s-s?ntese com excesso de solvente para a obten??o do catalisador Ti-MCM-41. O catalisador foi utilizado na cat?lise da rea??o de remo??o dos
BTEX em meio aquoso utilizando H2O2 como oxidante. Os materiais obtidos foram caracterizados por: DRX, TG/DTG, FTIR, adsor??o/dessor??o de N2, FRX-EDX, com o objetivo de verificar se o m?todo de impregna??o do tit?nio no suporte mesoporoso foi eficiente. Os testes catal?ticos foram realizados em reatores de 20 mL contendo solu??o aquosa de BTEX (100,0 μg/L), H2O2 (0,1 M) e Ti-MCM-41 (2,0 g/L) em meio acido. A rea??o ocorreu por 5 h a 60 ?C e as analises foram feitas por cromatografia a g?s com detector de fotoionizacao e amostrador por headspace est?tico. As caracteriza??es comprovaram a efic?cia do m?todo de s?ntese utilizado, assim como a incorpora??o do tit?nio no suporte. Os testes catal?ticos apresentaram resultados satisfat?rios na remo??o de mais de 95 % para os compostos
estudados, onde o catalisador 48% Ti-MCM-41 apresentou uma maior efici?ncia na remo??o dos compostos em estudo
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Metais pesados em nitossolo vermelho distr?fico fertilizado com dejeto l?quido de su?nos, sob manejos de fitomassa, em Campos Novos - SC / Heavy metals in a Typic Hapludox fertilized with pig slurry, under phytomass removal intensities, in Campos Novos - SCSILVA, Jo?o Ant?nio Montibeller Furtado e 26 August 2015 (has links)
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Previous issue date: 2015-08-26 / CAPES / FAPERJ / In the zones that produce swine, the farms have a high concentration of animals that generate large amounts of slurry, which becomes a problem due to lack of agricultural area for distribution, at the rates calculated to be used as a supply of nutrients to crops. Systematic application of pig slurry (PS) can increase the levels of heavy metals (HMs) in the soil. The HMs dynamics in the soil depends on their chemical form, the slurry characteristics, plant absorption capacity and the phytomass management. The purpose of this study was to study the effect of applying PS fertilizing and intensity of nutrient removal, represented by managements of biomass, in the dynamics of soil HMs. The levels of heavy metals (Cu, Zn, Mn, Ni and Pb) were evaluated in a area with Typic Hapludox soil, after three applications of PS. The Humic Acid (HA) obtained from PS samples was characterized in terms of elemental composition, nuclear magnetic resonance of carbon-13 and infrared spectroscopy, in order to evaluate their potential to interact with the HMs. The total contents of Cu, Zn, Mn, Ni and Pb was determined in feed samples, PS from slurry tanks on a finishing swine farm and plants fertilized with PS, consisting a consortium of lopsided oat (Avena strigose, Schreb.) and Italian rye grass (Lolium multiflorum Lam.). The dynamics of HMs in soil was assessed by determining the pseudototals levels in six layers (0-2.5; 2.5-5; 5-10; 10-20; 20-40; 40-80 cm), and bioavailable in the layer of most exploration of consortium roots studied (0-20 cm). The metals Cu, Zn, Mn, Ni e Pb were found in the feed, indicating the source and origin of the HMs in the PS. With 55% of aliphatic chains, 14% of oxygenated aliphatics and 15% of carboxyl, the characterization of HA in the PS showed a high capacity to interact and form soluble complexes with HMs. All analysed HMs had pseudototals levels that increased in all six layers of soil, as a function of the PS dose applied, and the bioavailable forms in the arable layer (0-20 cm). The management with higher intensity of biomass removal, the soil showed the lowest levels of HMs, pseudototal and bioavailables. The total metal accumulation in plants showed a positive and significant correlation with the levels of bioavailables in the soil, suggesting that the HMs were in exchangeable and/or hydrosoluble forms, capable of being transferred to water bodies and to enter the food chain. / Nas regi?es produtoras de su?nos, as granjas apresentam elevadas concentra??es de animais que geram grandes quantidades de res?duos, tornando-se um problema devido ? falta de ?rea agr?cola para sua distribui??o, em taxas calculadas para o fornecimento de nutrientes para as culturas.Aplica??es sistem?ticas de dejeto l?quido de su?nos (DLS) podem elevar os teores de metais pesados (MPs) no solo. A din?mica dos MPs depende da forma qu?mica que se encontram no solo, das caracter?sticas do res?duo aplicado, da absor??o pelas plantas e do manejo da fitomassa. Com o objetivo de estudar os efeitos da aplica??o de dejeto l?quido de su?nos e da intensidade de remo??o de nutrientes, representadas por manejos de fitomassa, na din?mica de MPs do solo, o presente trabalho avaliou os teores de metais pesados (Cu, Zn, Mn, Ni e Pb) em uma ?rea de Nitossolo Vermelho Distr?fico, ap?s tr?s aplica??es de DLS.Os ?cidos h?micos (AH) obtidos de amostras de DLS foram caracterizados quanto ? composi??o elementar,resson?ncia magn?tica nuclear do carbono-13 e espectroscopia de infravermelho, a fim de se avaliar o seu potencial de intera??o com os MPs. Foram determinados os teores totais de Cu, Zn, Mn, Ni ePb em amostras de ra??o, DLS oriundo de esterqueiras, e em tecido do cons?rcio de plantas de aveia preta (Avena strigosa Schreb.) e azev?m (Lolium multiflorum Lam.) adubadas com DLS. A din?mica dos MPs no solo foi avaliada atrav?s da determina??o dos teores pseudototais em seis camadas do solo (0-2,5; 2,5-5; 5-10; 10-20; 20-40, e 40-80 cm), e biodispon?veis na camada de maior explora??o das ra?zes do cons?rcio estudado (0-20 cm).Os metais Cu, Zn, Mn, Ni e Pb foram encontrados na ra??o, indicando a origem desses MPs no DLS. A caracteriza??o dos AH do DLS, com 55% de cadeias alif?ticas, 14% alif?ticas oxigenadas e 15% de carboxilas, demonstra a sua alta capacidade de intera??o e forma??o de complexos sol?veis com MPs. Todos os metais avaliados apresentaram ac?mulo nas seis camadas do solo em fun??o da dose de DLS aplicada, inclusive em formas biodispon?veis na camada ar?vel (0-20 cm). No manejo com maior intensidade de remo??o de fitomassa, o solo apresentou os menores teores de MPs, tanto pseudototais, como biodispon?veis. O ac?mulo total desses metais nas plantas apresentou correla??o positiva e significativa com os teores biodispon?veis do solo, indicando que os MPs se encontravam em formas troc?veis e/ou hidrossol?veis, com capacidade para serem transferidos para corpos h?dricos e entrar na cadeia tr?fica.
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Remo??o de metais pesados em efluentes sint?ticos utilizando vermiculita como adsorventeSilva, Roberta Pereira da 17 August 2010 (has links)
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Previous issue date: 2010-08-17 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico / Heavy metals are used in many industrial processestheirs discard can harm fel effects to
the environment, becoming a serious problem. Many methods used for wastewater
treatment have been reported in the literature, but many of them have high cost and low
efficiency. The adsorption process has been used as effective for the metal remoal ions.
This paper presents studies to evaluate the adsorption capacity of vermiculite as
adsorbent for the heavy metals removal in a synthetic solution. The mineral vermiculite
was characterized by differents techniques: specific surface area analysis by BET
method, X-ray diffraction, raiosX fluorescence, spectroscopy in the infraredd region of,
laser particle size analysis and specific gravity. The physical characteristics of the
material presented was appropriate for the study of adsorption. The adsorption
experiments weredriveal finite bath metod in synthetic solutions of copper, nickel,
cadmium, lead and zinc. The results showed that the vermiculite has a high potential for
adsorption, removing about 100% of ions and with removal capacity values about 85
ppm of metal in solution, 8.09 mg / g for cadmium, 8.39 mg/g for copper, 8.40 mg/g for
lead, 8.26 mg/g for zinc and 8.38 mg/g of nickel. The experimental data fit in the
Langmuir and Freundlich models. The kinetic datas showed a good correlation with the
pseudo-second order model. It was conducteas a competition study among the metals
using vermiculiti a adsorbent. Results showed that the presence of various metals in
solution does not influence their removal at low concentrations, removing approximat
wasely 100 % of all metals present in solutions / Os metais pesados s?o utilizados em muitos processos industriais e, quando descartados
ao meio ambiente, podem ocasionar efeitos prejudiciais aos seres vivos, tornando-se um
s?rio problema ambiental. Muitos m?todos usados para o tratamento de efluentes t?m
sido apresentados na literatura, mas muitos deles possuem alto custo e baixa efici?ncia.
O processo de adsor??o vem sendo utilizado como eficaz para a remo??o de ?ons
met?licos. Neste trabalho s?o apresentados estudos para avaliar a capacidade de
adsor??o da vermiculita, como adsorvente para a remo??o de metais pesados em
solu??o sint?tica. Realizou-se, inicialmente,a caracteriza??o do mineral vermiculita
natural por diferentes t?cnicas: an?lise da ?rea espec?fica superficial pelo m?todo de
BET, difra??o de raios-X, Fluoresc?ncia de raiosX, Espectroscopia na regi?o de
infravermelho, an?lise granulom?trica a laser e densidade espec?fica. As caracter?sticas
f?sicas apresentadas pelo material foram adequadas para o estudo de adsor??o. De posse
das an?lises de caracteriza??o foram executados ensaios de adsor??o, pelo m?todo de
banho finito para solu??es sint?ticas dos metais cobre, n?quel, c?dmio, chumbo e zinco.
Os resultados demonstraram que a vermiculita possui elevado potencial de adsor??o,
removendo praticamente 100% dos ?ons e apresentando valores para a capacidade de
remo??o, com cerca de 85 ppm de metal em solu??o, de 8,09 mg/g para o c?dmio, 8,39
mg/g para o cobre, 8,40 mg/g para o chumbo, 8,26 mg/g para o Zinco e 8,38 mg/g de
n?quel. Os pontos experimentais se ajustam aos modelos de Langmuir e Freundlich. Os
dados cin?ticos mostraram melhor correla??o com a equa??o de velocidade de pseudosegunda
ordem. Paralelamente ao estudo da capacidade de adsor??o do mineral
vermiculita, foi realizado o estudo da competi??o dos metais entre si, onde os resultados
demonstraram que a presen?a de v?rios metais em solu??o n?o influenciam na sua
remo??o em baixas concentra??es, removendo aproximadamente 100% de todos os
metais presentes nas solu??es
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Remo??o de metais utilizando o hexadecanoato de s?dioCarvalho, Giselle Kalline Gomes 28 November 2014 (has links)
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Previous issue date: 2014-11-28 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico - CNPq / Atividades industriais de minera??o, galvanoplastia e o processo de extra??o do
petr?leo, vem aumentando os n?veis de metais pesados, tais como Cu, Fe, Mg e Cd, nos
ecossistemas aqu?ticos. Este aumento est? relacionado ao descarte de efluentes contendo
teores desses elementos acima do valor m?ximo permitido por lei. M?todos como troca
i?nica, filtra??o por membranas e precipita??o qu?mica vem sendo estudados como meios de
tratamentos de efluentes contaminados por esses metais. A precipita??o de metais utilizando
tensoativos ani?nicos obtidos a partir de ?cidos carbox?licos surgiu como uma alternativa para
a remo??o de metais de efluentes industriais. A rea??o entre ?ons bivalentes dos metais e esses
tipos de tensoativos em solu??o aquosa leva a forma??o de carboxilatos de metais, que podem
precipitar na forma de flocos e serem removidos, posteriormente, por um processo de
decanta??o dos flocos formados ou por uma filtra??o simples. Neste trabalho, a extra??o de
metais ? realizada por meio da utiliza??o do tensoativo hexadecanoato de s?dio como agente
extrator. O objetivo principal ? estudar o efeito da varia??o da temperatura do meio, pH da
solu??o de metal e concentra??o do tensoativo no processo de remo??o do metal. A
modelagem estat?stica do estudo mostrou que o processo ? diretamente dependente das
varia??es de pH e concentra??o do tensoativo, por?m inversamente proporcional e pouco
dependente da varia??o de temperatura, sendo esse ?ltimo efeito considerado desprez?vel na
maioria dos casos. O estudo individual do efeito da temperatura apresenta uma forte
depend?ncia do processo ? temperatura de Kraft, tanto do tensoativo utilizado como agente
extrator como do tensoativo obtido ap?s a rea??o desse tensoativo com o metal. A partir dos
dados de temperaturas e concentra??es do tensoativo foi poss?vel o c?lculo da constante de
equil?brio para a rea??o entre o hexadecanoato de s?dio e ?ons cobre. Posteriormente, foram
determinados par?metros termodin?micos, comprovando que o processo ? exot?rmico e
espont?neo. / Industrial activities like mining, electroplating and the oil extraction process, are
increasing the levels of heavy metals such as Cu, Fe, Mg and Cd in aquatic ecosystems. This
increase is related to the discharge of effluents containing trace of this elements above the
maximum allowed by law. Methods such as ion exchange, membrane filtration and chemical
precipitation have been studied as a means of treatment of these metals contamination. The
precipitation of metals using anionic surfactants derived from carboxylic acids emerged as an
alternative for the removal of metals from industrial effluents. The reaction between bivalent
ions and these types of surfactants in aqueous solution leads to the formation of metal
carboxylates, which can precipitate in the form of flakes and are subsequently removed by a
process of decantation or simple filtration. In this work the metals extraction is performed by
using the surfactant sodium hexadecanoate as extracting agent. The main purpose was to
study the effect of temperature, solution pH, and concentration of surfactant in the metal
removal process. The statistical design of the process showed that the process is directly
dependent to changes in pH and concentration of surfactant, but inversely proportional and
somewhat dependent to temperature variation, with the latter effect being considered
negligible in most cases. The individual study of the effect of temperature showed a strong
dependence of the process with the Kraft point, both for the surfactant used as extracting
agent, as for the surfactant obtained after the reaction of this surfactant with the metal. From
data of temperatures and concentrations of the surfactant was possible to calculate the
equilibrium constant for the reaction between sodium hexadecanoate and copper ions. Later,
thermodynamic parameters were determined, showing that the process is exothermic and
spontaneous.
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