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Complexos met?licos de cobalto, n?quel e cobre com a Pirazina-2-carboxamida e 4- hidrazida ?cida piridincarbox?lica: s?ntese e caracteriza??oCarvalho, Genickson Borges de 29 February 2012 (has links)
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Previous issue date: 2012-02-29 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / This work involved the synthesis, characterization and proposing the molecular
structure of coordination compounds involving ligands pyrazine-2-carboxamide (PZA) and 4-
hydrazide acidic pyridine carboxylic (INH) and metals of the first transition series (M = Co2+,
Ni2+ and Cu2+). For the characterization of the compounds used were analytical techniques
such as infrared absorption spectroscopy average (FT-IR) molar conductivity measurements,
CHN elemental analysis, EDTA Complexometric, measurement of melting point, X-ray
diffraction by powder method, Thermogravimetry (TG) and Differential Thermal Analysis
(DTA) and Simultaneous Differential Scanning Calorimetry (DSC). The absorption spectra in
the infrared region suggested that the ligand coordination to the metal center occurs through
the carbonyl oxygen atom and nitrogen alpha pyrazine ring to those complexes formed with
PZA. For INH complexes with metal-ligand coordination is through the carbonyl oxygen and
nitrogen of the terminal hydrazide grouping. The conductivity measurements of the
complexes in aqueous solution they suggest to all behavior of the type 1:2 electrolytes, and
conduct of non-electrolytes in acetonitrile. The results obtained by CHN elemental analysis
and EDTA Complexometric allowed to infer the stoichiometry of the compounds synthesized.
For all of the complexes obtained was possible to record the melting points, neither of which
melted near the melting temperature of the free ligands. The X-ray diffraction showed that the
complexes of pyrazinamide exhibited diffraction lines, suggesting that these compounds are
crystalline, while compounds of isoniazid, with the exception of cobalt, exhibited diffraction
lines, indicating that they are crystalline. The results from the TG-DTA and DSC allowed
information regarding the dehydration and thermal decomposition of these complexes / Este trabalho consistiu na s?ntese, caracteriza??o e proposi??o da estrutura molecular
de compostos de coordena??o envolvendo os ligantes pirazina-2-carboxamida (PZA) e 4-
hidrazida ?cida piridincarbox?lica (INH) e os metais da primeira s?rie de transi??o (M = Co2+,
Ni2+ e Cu2+). Para a caracteriza??o dos compostos foram utilizadas t?cnicas de an?lise como:
Espectroscopia de absor??o no Infravermelho m?dio (FT-IR), medidas de condutividade
molar, An?lise Elementar de CHN, complexometria com EDTA, medidas do ponto de fus?o,
Difra??o de raios-X pelo m?todo do p?, Termogravimetria (TG) e An?lise T?rmica
Diferencial (DTA) simult?nea e Calorimetria Explorat?ria Diferencial (DSC). Os espectros de
absor??o na regi?o do infravermelho sugerem que a coordena??o do ligante ao centro
met?lico ocorreu atrav?s do ?tomo de oxig?nio carbon?lico e do nitrog?nio alfa do anel
piraz?nico para os complexos formados com a PZA. Para os complexos com a INH a
coordena??o ligante-metal se d? pelo oxig?nio da carbonila e nitrog?nio terminal do
grupamento hidrazida. As medidas de condutividade dos complexos em solu??o aquosa
sugerem para todos eles comportamento de eletr?litos do tipo 1:2; e comportamento de n?o
eletr?litos em acetonitrila. Os resultados obtidos pela an?lise elementar de CHN e
complexometria com EDTA permitiram inferir a estequiometria dos compostos sintetizados.
Para todos os complexos obtidos foi poss?vel registrar os pontos de fus?o, sendo que nenhum
deles fundiu pr?ximo da temperatura de fus?o dos ligantes livres. Os difratogramas de raios-X
mostraram que os complexos da pirazinamida apresentaram linhas de difra??o, sugerindo que
estes compostos s?o cristalinos, enquanto os compostos da isoniazida, com exce??o ao de
cobalto, apresentaram linhas de difra??o, indicando que os mesmos s?o cristalinos. Os
resultados a partir das curvas TG-DTA e DSC permitiram informa??es a respeito da
desidrata??o e decomposi??o t?rmica destes complexos
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Caracteriza??o genot?pica e estudo filogen?tico de Cryptosporidium spp. obtidos de diferentes hospedeiros / Genotypic characterization and phylogeny of Cryptosporidium spp. from different hostsHuber, Franziska 27 February 2007 (has links)
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Previous issue date: 2007-02-27 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / The objectives of the present study was the genetical characterizations of Cryptosporidium
spp. from different hosts, realize the sequencing an phylogenetic analysis, including the
deposit in GenBank of the first Cryptosporidium sequences of animal origin, from Brazil.
There were obtained fecal samples, containing Cryptosporidium oocysts from chiken, ducks,
quails and Guinea pigs from a public market localized in Rio de Janeiro city, from dairy calfs
maintained at a farm localized in the same city and from dogs and cats maintained at a shelter
localized in the city of Nova Igua?u. For the analysis was utilized the Nested-PCR of the
extracted DNA from 200μl of fecal suspension. For primary identification of
Cryptosporidium species was realized RFLP with enzymes SspI and VspI. DNA samples were
sequenced and phylogenetic analysis were conducted. There were diagnosed and sequenced
C. baileyi infecting two ducks (DQ855339 and DQ885340) and one quail (DQ885335) and C.
melagridis infecting one chicken (DQ885341). The sequences obtained form
Cryptosporidium infecting Guinea pigs received accession numbers DQ885337 and
DQ885338, both sequences were not identified with known Cryptosporidium species due to
the great genetic distance between them and those already available at GenBank, suggesting
that it may be a new genotype or species. Parasitizing cats was diagnosed C. felis (DQ885336)
and in one dog C. canis (DQ885334). One sample of C. parvum of calf origin was sequenced
and received accession number DQ885333. During analysis of RFLP pattern of the nested-
PCR product from 18Sr DNA was stated that only C. baileyi has a characteristic digestion
pattern. Other Cryptosporidium species should be digested by several other enzymes, for a
accurate diagnosis. At phylogenetic analysis was found a greater genetic distance between C.
felis and C. canis from Brazil when compared to the reference sequences obtained from
GenBank. Based on the phylogenetic groupings, a possible new species of Cryptosporidium
from Guinea Pigs calls attention for the existence of new species even in common pet
animals. As is the case of the Guinea Pig. The sequences obtained in this study are the first Brazilian sequences of C. baileyi, C. meleagridis, C. felis, C. canis and C. parvum deposited
in GenBank. / O presente trabalho teve por objetivo caracterizar geneticamente as esp?cies de
Cryptosporidium oriundos de v?rios hospedeiros, realizar o seq?enciamento e an?lises
filogen?ticas, incluindo o dep?sito das primeiras seq??ncias brasileiras de Cryptosporidium
spp. de origem animal no GenBank. Foram obtidas amostras fecais contendo oocistos de
Cryptosporidium de pintos, patos, codornas e porquinhos da ?ndia comercializados num
mercado municipal da cidade do Rio de Janeiro, de bezerros de uma propriedade voltada ?
produ??o leiteira localizada no mesmo munic?pio e de gatos e c?es de um abrigo para animais
localizado no munic?pio de Nova Igua?u. Para as an?lises foi utilizado Nested-PCR do DNA
extra?do a partir de 200μl de solu??o fecal. Foi realizada RFLP dos produtos obtidos no
Nested-PCR, utilizando-se as enzimas SspI e VspI, para uma identifica??o preliminar das
esp?cies de Cryptosporidium presentes. As amostras de DNA foram seq?enciadas e an?lises
filogen?ticas foram conduzidas. Foram diagnosticados e sequenciados C. baileyi infectando
dois patos (DQ855339 e DQ885340) e uma codorna (DQ885335) e C. melagridis infectando
um pinto (DQ885341). As seq??ncias dos Porquinhos da ?ndia receberam os n?meros de
acesso DQ885337 e DQ885338, sendo que ambas as seq??ncias n?o puderam ser
identificadas como esp?cie conhecida de Cryptosporidium, devido ? grande dist?ncia gen?tica
entre elas e aquelas j? depositadas no GenBank, sugerindo que se trate de um gen?ptipo ou
esp?cie nova. Parasitando os gatos foi diagnosticado C. felis (DQ885336) e em um c?o C.
canis (DQ885334). Uma das amostras de C. parvum de bovinos foi seq?enciada, sendo
depositada no GenBank sob n?mero de acesso DQ885333. Durante as an?lises dos s?tios de
corte enzim?tico dos produtos da Nested-PCR do gen 18Sr DNA, a ?nica esp?cie que
realmente possue padr?o de corte caracter?stico ? C. baileyi. As demais esp?cies de
Cryptosporidium deveriam ser submetidas ? a??o de outras enzimas, para um diagn?stico
acurado. Nas an?lises filogen?ticas foi observada uma dist?ncia gen?tica maior entre C. felis e
C. canis isolados no Brasil quando comparados ?s seq??ncias do GenBank. Com base nos
dados apresentados pelo agrupamento filogen?tico, uma poss?vel nova esp?cie chama a
aten??o ? presen?a de esp?cies desconhecidas de Cryptosporidium, mesmo em animais
comuns de estima??o, como ? o caso do Porquinho da ?ndia. Estas s?o as primeiras seq??ncias
de C. baileyi, C. meleagridis, C. felis, C. canis e C. parvum do Brasil depositadas no
GenBank.
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Perfil de suscetibilidade e detec??o de marcadores gen?ticos de resist?ncia em Streptococcus Agalactiae isolados de amostras animais e humanasCunha, Cleia Maria Monteiro da 09 October 2008 (has links)
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Previous issue date: 2008-10-09 / Streptococcus agalactiae, also referred as group B streptococci (GBS) are commensals
microorganisms adapted to asymptomatic colonization of the mammalians gut and
genitourinary tract. Initially, this specie was recognized as a major etiologic agent for bovine
mastitis but has becoming a leading cause of invasive infections in human neonates. The
reasons behind the prompt and persistent emergence of GBS neonatal disease have not been
completely elucidated, once human and bovine GBS populations are assumed be distinct and
unrelated by divergence on their own physiological characters. Aiming to contribute for the
characterization of the two S. agalactiae sub-populations that are in a proximal coexistence in
the Rio de Janeiro state, this study evaluated phenotypic and genotypic diversity aspects of
regional groups of GBS. The first made up of 50 isolates obtained from human specimens
whilst the other group was constituted of 36 isolates from milk of dairy cows presenting
clinical or sub clinical mastitis. Phenotypic characterization was based on physiological and
serological tests, antimicrobial susceptibility assays were carried out by the disk standard
procedure and microdilution method. The genetic aspect was assessed by PCR for detection of
genes associated with resistance to tetracycline. According to the results of physiologic tests,
β-hemolysis was a faculty shared by about 28% of bovine isolates and 100% of human
isolates. GBS bovine isolates also shows different profile of sensitivity to bacitracin, only
33% of them were susceptive to the antibiotic, regardless of the whole human isolates set had
demonstrated a 100% susceptive pattern to this substance. A 100% sensitivity percentual to
penicillin was shared by all isolates assayed in this study corroborating the general procedure
for antibiotic therapy of GBS infection. Otherwise, and in an overall view, bovine isolates
showed higher resistance rates to a set of antibiotics, including cephoxitin, erytromicin,
clyndamicin, sulphamethoxazole, azithromycin and ciprofloxacin than in their human
counterparts. In a similar sense, it was observed in this study that 13,9% of the animal GBS
isolates expressed cMLSB and 2,8 % M phenotypes. The M phenotype was expressed in 6%
of the human related isolates as the unique MLSB parameter. Genetical assays performed
detected 13,8% (5/36) and 14% (7/50) for tet (M), and 30,5% (11/36) and 10% (5/50) for de
tet (O), respectively, in bovine and human isolates. These genes are implicated in tetracycline
resistance by ribosome protection mechanism through enzymatic structural modification. / Os Streptococcus agalactiae, tamb?m designados como estreptococos do grupo B
(EGB), s?o microrganismos comensais adaptados para fazer a coloniza??o assintom?tica do
tubo digestivo, e do trato geniturin?rio de mam?feros. Inicialmente, reconhecida como um dos
mais importantes agentes etiol?gicos da mastite bovina, esta esp?cie foi tamb?m implicada
como uma das principais causas de infec??es invasivas em rec?m-nascidos humanos. As
raz?es para a r?pida e consistente evolu??o do EGB como importante agente causal de
infec??es neonatais ainda n?o foram completamente elucidadas, uma vez que as
subpopula??es de EGB nos isolados de humanos e bovinos s?o independentes e distintas com
base no reconhecimento da diversidade de suas caracter?sticas fisiol?gicas. Com o objetivo de
contribuir para a caracteriza??o das duas subpopula??es de S. agalactiae que coexistem no
Estado do Rio de Janeiro, este estudo avaliou aspectos da diversidade gen?tica e fenot?pica de
dois grupos de EGB regionais, sendo o primeiro composto por 50 isolados obtidos a partir de
esp?cimes cl?nicos humanos, e o segundo constitu?do por 36 isolados a partir de leite de vacas
leiteiras com ind?cios de mastite cl?nica ou subcl?nica. A caracteriza??o fenot?pica dos
isolados foi baseada em testes sorol?gicos e fisiol?gicos, testes de suscetibilidade
antimicrobiana realizados com t?cnica padronizada para utiliza??o de disco de difus?o e pelo
m?todo de microdilui??o. O aspecto gen?tico foi avaliado pela aplica??o de PCR para
detec??o de genes associados ? resist?ncia ? tetraciclina. Os testes fisiol?gicos demonstraram
que a capacidade de promover β-hem?lise era uma caracter?stica partilhada por cerca de 28%
dos isolados a partir do material de natureza bovina, mas que manifestava-se em todos os
isolados de origem humana. Os isolados de EGB bovinos tamb?m mostraram um perfil
diferente quanto ? sensibilidade ? bacitracina, uma vez que apenas 33% delas se revelaram
suscet?veis a esse antibi?tico contra 100% de sensibilidade para os isolados de origem
humana. O percentual de 100% de sensibilidade ? penicilina demonstrado por todos os
isolados analisados neste estudo, tamb?m corrobora a import?ncia do uso desse antibi?tico
como procedimento geral na terapia de infec??es por EGB. De uma forma geral, neste estudo
foi observado que os isolados originados de material bovino demonstraram percentuais de
resist?ncia ao conjunto de antibi?ticos analisados (cefoxitina, eritromicina, clindamicina,
sulfametoxazol, azitromicina e ciprofloxacina) superiores aos observados em isolados de
material humano. Foi tamb?m observado que 13,9% dos isolados de EGB animais
examinados expressaram o fen?tipo cMLSB e 2,8% o fen?tipo M. O fen?tipo M foi o ?nico
par?metro MLSB expresso entre os isolados de S. agalactiae humanos, com um percentual de
6%. Quanto ? presen?a de genes de resist?ncia a tetraciclina entre as subpopula??es de EGB,
detectou-se percentuais de 13,8% (5/36) e 14% (7/50) para tet(M), e 30,5% (11/36) e 10%
(5/50) para tet(O), respectivamente, nos isolados bovinos e humanos avaliados. Estes genes
est?o implicados na resist?ncia ? tetraciclina por um mecanismo prote??o ribossomal, pela
altera??o estrutural mediada por a??o enzim?tica.
Palavras-chave: Streptococcus agalactiae, caracteriza??o fenot?pica, gene tet
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Avalia??o da argila atapulgita para potencial uso como excipiente farmac?utico em formas s?lidasSoares, Daiane dos Santos 22 May 2013 (has links)
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Previous issue date: 2013-05-22 / Clays are natural materials that have great potential for use as excipients for solid dosage forms. Palygorskite is a type of clay that has hydrophilic properties as well as a large surface area, which could contribute to the dissolution of drugs. Thus, the present study aims to evaluate the use of palygorskite clay, from Piaui (Northeast region of Brazil), as a pharmaceutical excipient for solid dosage forms, using rifampicin and isoniazid as the model drugs. The former is a poorly soluble drug often associated with isoniazid for tuberculosis treatment. Palygorskite was characterized by X-ray diffraction (XRD), X-ray fluorescence (XRF), particle size, transmission electron microscopy (TEM), scanning electron microscopy (SEM) and specific surface area (BET). The rheological and technological properties of palygorskite were determined and compared to those of talc, magnesium stearate and Aersosil 200. Mixtures between drugs and palygorskite were analyzed by differential scanning calorimetry (DSC), thermogravimetric analysis (TG) combined with thermal analysis (DTA) and Fourier Transform Infrared Spectroscopy (FT-IR), where the results were compared with those of the individual compounds. In addition, dissolution studies of solid dispersions and capsules containing the drugs, mixed with either palygorskite or a mixture of talc and magnesium stearate, were performed. The results showed that palygorskite has small particles with a high surface area. Its rheological characteristics were better than those of others commonly used glidants and lubricants. There was no interaction between palygorskite and the drugs (rifampicin and isoniazid). Among the dispersions studied, the mixture with palygorskite (5%) showed the highest drug dissolution when compared to other excipients. The dissolution of the rifampicin capsules containing palygosrkite was faster in higher concentrations. However, these differences were statistically different only in the first minutes of the dissolution experiment. The dissolution profile of isoniazid was also statistically different on the initial part of the experiment. The formulations prepared with isoniazid and palygorskite showed higher drug dissolution, but it was in descending order of concentration. According to these results, the palygorskite clay used in this study has great potential for application as an excipient for solid dosage forms / Argilas s?o materiais naturais, com baixa toxicidade e com potencial para atuar como excipiente. A atapulgita ? uma argila com caracter?stica hidrof?lica e grande ?rea superficial. Assim, este trabalho tem por objetivo avaliar o uso da atapulgita como excipiente farmac?utico em formas s?lidas, utilizando a rifampicina e a isoniazida como f?rmacos-modelo. A atapulgita ? proveniente do Estado do Piau?, Nordeste, Brasil. A rifampicina ? um f?rmaco de baixa solubilidade frequentemente associado ? isoniazida para o tratamento da tuberculose. Inicialmente a atapulgita foi caracterizada por difra??o de raios-X (DRX), fluoresc?ncia de raios-X (FRX), an?lise granulom?trica, microscopia eletr?nica de transmiss?o (MET) e varredura (MEV) e determina??o da ?rea de superf?cie espec?fica (BET). As propriedades reol?gicas e tecnol?gicas da argila foram determinadas e comparadas ao talco, estearato de magn?sio e Aerosil 200. Misturas entre os f?rmacos e a argila (1:1, 1:2 e 1:1:1), bem como os materiais isolados, foram avaliadas por calorimetria explorat?ria diferencial (DSC), an?lise termogravim?trica (TG) combinada ? an?lise t?rmica diferencial (DTA) e espectroscopia na regi?o do infravermelho com transformada de Fourier (FT- IR). Estudos de dissolu??o de dispers?es s?lidas e de c?psulas contendo os f?rmacos e a atapulgita foram realizados e comparados ao emprego de talco e estearato de magn?sio. Os resultados mostraram que a atapulgita apresenta part?culas pequenas, com grande ?rea de superf?cie. Apresentou boas caracter?sticas reol?gicas quando comparada ao demais reguladores de fluxo. N?o foi evidenciada intera??o com os f?rmacos testados. Entre as dispers?es, as misturas com atapulgita (5%) mostraram maior dissolu??o dos f?rmacos em rela??o a outros excipientes . O perfil de dissolu??o da rifampicina foi superior na formula??o de c?psula contendo atapulgita em maior concentra??o, sendo estatisticamente diferente nos primeiros minutos. O perfil de dissolu??o da isoniazida tamb?m se mostrou estatisticamente diferente nos primeiros minutos, sendo as formula??es com atapulgita as que apresentaram maior dissolu??o do f?rmaco, por?m em ordem decrescente de concentra??o. A argila atapulgita apresenta, portanto, potencial para aplica??o como excipiente em formas farmac?uticas s?lidas
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Uso do GPR na caracteriza??o da pluma de contamina??o gerada por hidrocarbonetos a partir de um posto de combust?vel na Praia de B?zios/RNSchmidt, Ana Cristiane Paulino de Sousa 30 June 2009 (has links)
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Previous issue date: 2009-06-30 / This work is the application of geophysical methods, using the Ground Penetrating Radar (GPR), with the objective of survey in a subsurface plume of contamination caused by a disabled gas station. The gas station is located on the B?zios beach in southern coast of the state to Rio Grande do Norte in an Area of
Environmental Protection called Bonfim-Guara?ra. The interest to develop this work was the presence of contaminants (hydrocarbons) in a well located on the desktop, previously used for the abstraction of groundwater for residents living near the site. Were raised 15 geophysical survey lines totaling 775,48 lifting and installed 4 piezometer, to confirm the contamination and prepare a pluviometric map that helped in indicating the direction of local groundwater flow, thus showing the direction of movement of the probably plume of contamination. From the processing of the GPR lines was possible to identify two likely phases of contamination according to the classification proposed by Azambuja et al 2000, which are called phase absorbed and dissolved phase / A presente disserta??o corresponde a aplica??o da metodologia geof?sica, utilizando para isto o Ground Penetrating Radar (GPR), com o objetivo de obter um imageamento em subsuperficie de uma pluma de contamina??o ocasionada por um posto de revenda de combust?vel que se encontra desativado. Este posto
esta localizado na praia de B?zios litoral sul do estado do Rio Grande do Norte dentro de uma ?rea de Prote??o Ambiental denominada de Bonfim-Guara?ra. Esse estudo foi realizado a partir da descoberta da contamina??o por hidrocarboneto obtido atrav?s de sondagem realizada para capta??o de ?gua
subterr?nea por moradores que residem pr?ximo ao local. Foram levantadas 15 linhas de sondagem geof?sica totalizando 775,48 metros de levantamento e instalados 4 piez?metros, para confirma??o da contamina??o e elabora??o de um mapa potencim?trico que auxiliou na indica??o do sentido do fluxo
subterr?neo local, mostrando assim o sentido de movimenta??o da pluma de contamina??o. A partir do processamento das linhas de GPR foi poss?vel identificar duas prov?veis fases de contamina??o de acordo com a classifica??o proposta por Azambuja et al 2000, as quais s?o denominadas de fase absorvida e fase dissolvida
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Estudo sobre tratamento t?rmico e mudan?a superficial da diatomita de Puna?/RN para o desenvolvimento de um auxiliar de filtra??oNascimento, Carlos Rener do 30 December 2013 (has links)
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Previous issue date: 2013-12-30 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior / A diatomita ? um material natural que possui in?meras aplica??es devido ?s mudan?as
nas suas propriedades f?sica e qu?mica ap?s processamento. Atualmente, ? utilizada
na ind?stria como isolante ac?stico, auxiliar de filtra??o e carga industrial. O
material filtrante deve apresentar composi??o qu?mica de material inerte, o que confere
? diatomita um alto valor comercial e desempenho, n?o encontrados em outros materiais
particulados, para esta aplica??o. A diatomita sofre altera??es superficiais ap?s tratamento
t?rmico em altas temperaturas, a partir de 800?C, apresentando propriedades que
permitem sua aplica??o nas ind?strias aliment?cias, de bebidas, farmac?uticas, t?xteis e
cosm?ticas. Neste trabalho, desenvolveu-se um estudo sobre tratamento t?rmico em diatomita
natural a fim de adequar suas propriedades ? aplica??o como auxiliar de filtra??o.
Os tratamentos t?rmicos foram realizados em forno aberto nas temperaturas de 800?C,
1000?C e 1200?C, por um tempo de 24 horas. Foram adicionados tamb?m reagentes na
constitui??o das amostras em an?lise. Os reagentes usados foram, o carbonato de s?dio
(Na2CO3) e o cloreto de s?dio (NaCl). As amostras foram caracterizadas por difra??o
de raios-x, fluoresc?ncia de raios-x, microscopia eletr?nica de varredura, an?lise de distribui??o
e tamanho de part?culas, ?rea superficial especifica pelo m?todo BET, e volume de
poros pelo m?todo BJH. Os resultados mostraram uma redu??o na porosidade do material
bem como um incremento significativo da ?rea superficial especifica ap?s tratamento
t?rmico e com os reagentes na propor??o de 3% em peso. As diatomitas, ap?s tratamento
t?rmico, sofreram altera??es na sua colora??o, variando nas cores branca, creme e bege,
que interferem diretamente na velocidade do processo de filtra??o de materiais. Todos
os resultados obtidos antes e ap?s tratamento t?rmico do material foram comparados aos
valores obtidos para as amostras j?a usadas industrialmente, da ind?stria brasileira e americana,
que foram caracterizadas atrav?s dos mesmos m?todos experimentais realizados
com as amostras em estudo, e indicaram uma efici?ncia promissora ao material estudado
da regi?o de Puna? - RN, ap?s seu processamento; adi??o de reagentes e tratamento
t?rmico, como elemento na composi??o de filtrante. / The diatomite is a natural material that has numerous applications due to changes
in their physical and chemical properties after processing. It is currently used in the
industry as a sound insulator , filter aid and industrial load . The filter material shall be
inert chemical composition , which will diatomite confers a high commercial value and
performance not found in other particulate materials , for this application. The diatomite
surface undergoes changes after thermal treatment at high temperatures , from 800?C ,
with properties that enable its application in the food , beverage , pharmaceutical , cosmetic
and textiles . In this work , we developed a study on thermal treatment on natural
diatomite to adapt their properties to the application as a filter aid . The heat treatments
were performed in an open oven at temperatures of 800?C , 1000?C and 1200?C for
a time of 24 hours. Reagents were added in the constitution of the samples analyzed.
The reagents used were sodium carbonate (Na2CO3 ) and sodium chloride (NaCl) . The
samples were characterized by x - ray diffraction , x -ray fluorescence , scanning electron
microscopy , analysis and particle size distribution , specific surface area by the BET
method , and pore volume by BJH method. The results showed a reduction in porosity of
the material as well as a significant increase in specific surface area after heat treatment
and the reactants in the ratio of 3 wt%. The diatomaceous earth , after heat treatment ,
undergone changes in its coloration , varying in white, cream and beige , which directly
interferes with the speed of filtration materials process. All results obtained before and
after heat treatment of the material with the values obtained for samples already used
industrially , Brazilian and American industry , which were characterized using the same
test methods performed with the samples in the study were compared and showed promising
efficiency when material studied in the region of Puna? - RN , after processing ,
reagent addition and heat treatment, as an element in the composition of filter .
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Tratamento superficial de argilas com cera de carna?ba e microemuls?o de ?leo de cocoBorba, Loiva Liana Santos 14 July 2014 (has links)
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Previous issue date: 2014-07-14 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / A adsor??o ? um processo que tem se tornado indispens?vel devido a polui??o causada pela atividade industrial. Adsorventes mais vi?veis economicamente est?o sendo testados para substituir os materiais de alto custo utilizados. As argilas podem ser utilizadas como adsorventes e s?o materiais de baixo custo, naturais com propriedades vi?veis para a aplica??o no processo de adsor??o, modifica??es estruturais s?o realizadas com facilidade nesses materiais promovendo adsor??o seletiva. O objetivo deste trabalho foi sintetizar e caracterizar adsorventes aplicados na adsor??o de compostos org?nicos. Os adsorventes foram caracterizados pelas t?cnicas de DRX, MEV, FTIR e TG. Os resultados mostram que os materiais estudados possuem afinidade com compostos org?nicos e podem ser aplicados como adsorventes. Os melhores resultados foram aqueles tratados com microemuls?o apresentando afinidade na adsor??o de compostos org?nicos e inorg?nicos. Os materiais estudados s?o vi?veis e podem ser aplicados no tratamento de efluentes contaminados em escala industrial. / Adsorption is a process that has become indispensable due to pollution caused by
industrial activity. More economically viable adsorbents are being tested to replace the
high cost of materials used. The clays can be used as adsorbents and are low cost
materials, natural properties feasible for the application in the adsorption process,
structural modifications are performed with ease promoting selective adsorption in these
materials. The objective of this study was to synthesize and characterize adsorbents
used in the adsorption of organic compounds. The adsorbents were characterized by the
techniques of XRD, SEM, FTIR and TG. The results show that the studied materials
have affinity to organic compounds and can be applied as adsorbents. The materials
studied are viable and can be applied in the treatment of effluents contaminated in
industrial scale.
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Caracteriza??o e separa??o f?sica de placas de circuito impresso de computadores obsoletos / Characterization and physical separation of printed circuit boards obsolete computersMedeiros, Nat?lia Moraes 25 August 2015 (has links)
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Previous issue date: 2015-08-25 / Conselho Nacional de Desenvolvimento Cient?fico e Tecnol?gico (CNPq) / O consumo desenfreado de equipamentos eletr?nicos juntamente com a r?pida imers?o de novas tecnologias no mercado impulsiona o crescimento acelerado de res?duos eletroeletr?nicos. Esses res?duos s?lidos, em sua maioria, contem placas de circuito impresso em sua estrutura. Estas, por apresentarem muitos metais dentre eles metais pesados, s?o altamente t?xicas. Os res?duos eletr?nicos s?o descartados de forma indevida e indiscriminadamente, normalmente sem nenhum tratamento e junto com os demais res?duos urbanos, contaminando o meio ambiente e causando graves problemas a sa?de humana. Al?m desses metais, h? tamb?m metais preciosos e de base de alto valor agregado, que podem ser recuperados e reciclados, reduzindo a explora??o dos recursos naturais. Assim, devido ao alto potencial de crescimento e reutiliza??o desses res?duos, processos de tratamento, de caracteriza??o e de separa??o foram aplicados ?s placas de circuito impresso. As placas foram submetidas a tratamentos f?sicos, como desmantelamento, moagem, separa??o granulom?trica, separa??o magn?tica e por tratamentos qu?micos como pir?lise e lixivia??o. Atrav?s dos processos de caracteriza??o (pir?lise e lixivia??o) as propor??es dos componentes das faixas granulom?tricas foram determinadas: 46,08% de metais; 23,32% de pol?meros e 30,60% de cer?micos. Observou-se tamb?m pela separa??o granulom?trica, que os componentes met?licos tendem a se concentrarem nas fra??es mais grosseiras, enquanto que os materiais polim?ricos e cer?micos nas fra??es finas. Do processo de separa??o magn?tica obteve-se 12,08% de material magn?tico e 82,33% de material n?o magn?tico. / The unbridled consumption of electronic equipment associated with fast immersion of new technologies on the market leads to the accelerated growth of electronic waste. Such waste mostly contains printed circuit boards in its structure. Printed circuit boards have many metals, including heavy metals, being highly toxic. Electronic waste is discarded improperly and indiscriminately, usually without any previous treatment and with other municipal waste, contaminating the environment and causing serious problems to human health. Beyond these metals, there are also precious metals and high value-added basis, that can be recovered and recycled, reducing the exploration of natural resources. Thus, due to the high growth potential and reuse of these waste treatment processes, characterization and separation were applied to the printed circuit boards. The printed circuit boards were subjected to physical treatments such as dismantling, crushing, sizing separation, magnetic separation and chemical treatments such as pyrolysis and leaching. Through characterization process (pyrolysis and leaching) the proportions of the components of the granulometric range were determined: 46,08% of metals; 23,32% of polymers and 30,60% of ceramics. It was also observed by particle size separation that metal components tend to concentrate in coarse fractions, while polymeric and ceramic components in fine fractions. From the magnetic separation process was obtained 12,08% of magnetic material and 82,33% of non-magnetic material.
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S?ntese e caracteriza??o de complexos de Co(II) e Ni(II) com l-dopa, carbidopa e benzimidazolAra?jo, Antonio Marcos Urbano de 27 January 2016 (has links)
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Previous issue date: 2016-01-27 / Coordena??o de Aperfei?oamento de Pessoal de N?vel Superior (CAPES) / Foram sintetizados neste trabalho em solu??o aquosa os seguintes compostos de coordena??o: [Ni(LDP)(H2O)2Cl2].2H2O, [Co(LDP)Cl2].3H2O, [Ni(CDP)Cl2].4H2O, [Co(CDP)Cl2].4H2O, [Ni(BDZ)2Cl2].4H2O e [Co(BDZ)2Cl2].(H2O). Esses complexos foram sintetizados por adi??o estequiom?trica do ligante nas respectivas solu??es de cloretos do metal. A precipita??o ocorreu ap?s a secagem dos solventes sob temperatura ambiente. A caracteriza??o e proposta das estruturas foram realizadas utilizando-se de m?todos convencionais de an?lise tais como: an?lise elementar (CHN), espectroscopia de absor??o na regi?o do infravermelho com transformada de Fourier (FTIR), difratometria de raios X pelo m?todo do p? e as t?cnicas termoanal?ticas TG/DTG (termogravimetria/termogravimetria derivada) e DSC (calorimetria explorat?ria diferencial). Estas t?cnicas forneceram informa??es sobre desidrata??o, modos de coordena??o, comportamento t?rmico, composi??o e estrutura dos compostos sintetizados. Com os resultados das curvas TG, p?de-se estabelecer a f?rmula geral de cada composto sintetizado. Pela an?lise dos difratogramas de raios X foi observado que quatro dos complexos sintetizados apresentam estrutura n?o cristalina que foram os complexos obtidos a partir da L-dopa e Carbidopa e para os complexos obtidos a partir do benzimidazol obteve-se estruturas cristalinas. As observa??es dos espectros na regi?o do infravermelho sugeriram uma coordena??o monodentada do ligante aos respectivos centros met?licos atrav?s do grupo amina para todos os complexos. As curvas TG-DTG e DSC forneceram informa??es e importantes sobre o comportamento e a decomposi??o t?rmica dos compostos sintetizados. Os dados de condutividade molar apontaram que as solu??es dos complexos formados se comportam como um n?o-eletr?lito, o que implica dizer que o cloro est? coordenado ao ?tomo central nos complexos. / Were synthesized in this work in the following aqueous solution coordination
compounds: [Ni(LDP)(H2O)2Cl2].2H2O, [Co(LDP)Cl2].3H2O, [Ni(CDP)Cl2].4H2O,
[Co(CDP)Cl2].4H2O, [Ni(BDZ)2Cl2].4H2O and [Co(BDZ)2Cl2(H2O)2]. These
complexes were synthesized by stoichiometric addition of the binder in the respective
metal chloride solutions. Precipitation occurred after drying the solvent at room
temperature. The characterization and proposed structures were made using
conventional analysis methods such as elemental analysis (CHN), absorption
spectroscopy in the infrared Fourier transform spectroscopy (FTIR), X-ray diffraction
by the powder method and Technical thermoanalytical TG / DTG (thermogravimetry /
derivative thermogravimetry) and DSC (differential scanning calorimetry). These
techniques provided information on dehydration, coordination modes, thermal
performance, composition and structure of the synthesized compounds. The results of
the TG curve, it was possible to establish the general formula of each compound
synthesized. The analysis of X-ray diffraction was observed that four of the synthesized
complex crystal structure which does not exhibit the complex was obtained from Ldopa
and carbidopa and the complex obtained from benzimidazole was obtained crystal
structures. The observations of the spectra in the infrared region suggested a
monodentate ligand coordination to metal centers through its amine group for all
complexes. The TG-DTG and DSC curves provide important information and on the
behavior and thermal decomposition of the synthesized compounds. The molar
conductivity data indicated that the solutions of the complexes formed behave as a nonelectrolyte,
which implies that chlorine is coordinated to the central atom in the
complex.
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Estudo do potencial refrat?rio de argilas s?lico-aluminosas do Rio Grande do NorteLima, Angelica Gilksana Souza de 28 February 2011 (has links)
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Previous issue date: 2011-02-28 / The segment of the structural ceramics industry is one of the most important to the economy of Rio Grande do Norte. The supply chain makes a total of 206 companies that are distributed in 39 counties, concentrated in three regional centers: Serid? Apodi / Assu and great Natal. The ceramic industry in the state is around 80 million pieces per month, with 50,186 million of these tiles, which makes the Rio Grande do Norte one of the largest manufacturers of product in the Country. Different ceramic products can be manufactured by mixing two or more clays and accessory minerals. Mixtures acquire characteristics and form what is called the ceramic body. Refractory masses have a high melting point and thermal shock support.
Its composition contains refractory clays with a little iron oxide and material fluxes. A line of semi-refractory ceramic products that stands out for its high added value are the bricks in ivory or red, used in building barbecues, fireplaces, wood stoves and braziers. The aim of this study was to use alumina-clay or silica- alumina-clay to the industrial RN, for the production of refractory bricks semi-refractory burning light. Clay and Kaolin were characterized for their chemical and mineralogical composition, immediately after ceramic bodies were made with different concentrations of the components, they were raised, pressed and sintered. After sintering the resulting products were characterized in terms of mechanical, thermal and dimensional than the characterization by X-ray diffraction and scanning electron microscopy. After obtaining the results, we concluded that the studied clay can be used for the production of semi-refractory bricks / O segmento da ind?stria cer?mica estrutural ? um dos mais importantes para a economia do Rio Grande do Norte. A cadeia produtiva soma um total de 206 empresas que est?o distribu?das em 39 munic?pios e concentradas em tr?s p?los regionais: Serid?, Apodi/Assu e na grande Natal. A produ??o da ind?stria cer?mica no Estado gira em torno de 80 milh?es de pe?as/m?s, sendo 50.186 milh?es delas telhas, o que faz do Rio Grande do Norte um dos maiores fabricantes do produto no Pa?s. Diferentes produtos cer?micos podem ser fabricados atrav?s da mistura de duas ou mais argilas com minerais acess?rios. As misturas adquirem caracter?sticas pr?prias e formam o que se denomina massa cer?mica. Massas refrat?rias apresentam alto ponto de fus?o e suportam choque t?rmico. Sua composi??o cont?m argilas refrat?rias pobres em ?xido de ferro e materiais fundentes. Uma linha de produtos cer?micos semi-refrat?rios que se destaca pelo seu alto valor agregado s?o os tijolos aparentes na cor marfim ou avermelhado, utilizados na constru??o de churrasqueiras, lareiras, fog?es a lenha e braseiros. O objetivo do presente trabalho foi estudar a utiliza??o de argilas aluminosas ou s?lico-aluminosas do parque industrial do RN, para a produ??o de tijolos semi-refrat?rios de queima clara. A argila e o caulim foram, caracterizadas quanto ? sua composi??o qu?mica e mineral?gica, logo ap?s foram formuladas massas cer?micas com diferentes concentra??es dos componentes, estas foram formuladas, prensadas e sinterizadas. Ap?s a sinteriza??o os produtos resultantes foram caracterizados do ponto de vista mec?nico, t?rmico e dimensional al?m da caracteriza??o por difratometria de raios-X e microscopia eletr?nica de varredura. Com a obten??o dos resultados pudemos concluir que a argila estudada pode ser utilizada para a produ??o de tijolos semi-refrat?rios
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