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Caracterização de cálculos renais por análise térmica; Characterization of kidney stone by thermal analysis

BRANCO, C. H. D.; SILVA, A. L.; LUIZ, J. M.; MERCURI, L. P.; MATOS, J. R.
Fonte: Fundação Editora da Universidade Estadual Paulista Júlio de Mesquita Filho - UNESP Publicador: Fundação Editora da Universidade Estadual Paulista Júlio de Mesquita Filho - UNESP
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
27.59%
Dez amostras de cálculos renais foram estudadas por Análise Elementar de CHN (EA), Espectroscopia de Absorção no Infravermelho (IV) e Difração de raios X pelo método de Pó (XRD). O comportamento térmico das amostras foi estudado por Termogravimetria/Termogravimetria Derivada (TG/DTG) e por Calorimetria Exploratória Diferencial (DSC). Os resultados de EA, Espectroscopia de Absorção IV e XRD mostraram a presença de estruvita [NH4Mg(PO4).6H2O], apatita, oxalato de cálcio monohidratado e oxalato de cálcio dihidratado. As curvas TG e DSC permitiram classificar as amostras em dois grupos diferentes: Grupo I mostrando comportamento térmico típico de estruvita e Grupo II apresentando um perfil termoanalítico característico de mistura de oxalatos.; Ten samples of kidney stone had been studied through elemental analysis of CHN (EA), Infrared Absorption Spectroscopy and X-Ray Powder Diffraction (XRD). The thermal behavior of the samples is studied by Thermogravimetry/Derivative Thermogravimetry (TG/DTG) and Differential Scanning Calorimetry (DSC). The results of AE, IV absorption Spectroscopy and XRD showed the presence of struvite (NH4Mg [PO4].6H2O), apatite, monohydrated calcium oxalate and dihydrated calcium oxalate. The TG and DSC curves allowed to classify the samples in two different groups: Group I show typical thermal behavior of struvite and Group II present a profile thermal analytical characteristic of a mixture of calcium oxalate.; FAPESP; Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES); CNPq

Tratamento físico-químico de lixiviado de aterro sanitário pré-tratado por processo biológico aeróbio.; Physico-chemical treatment of landfill leachate from pre-treated by aerobic biological process.

Amaral, Mailer Sene
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: dissertação de mestrado Formato: application/pdf
Publicado em 22/05/2009 Português
Relevância na Pesquisa
27.59%
Lixiviados de aterros sanitários apresentam altas concentrações de nitrogênio amoniacal e matéria orgânica, além de outros poluentes, que não permitem seu descarte no meio ambiente, sem um prévio tratamento. Lixiviados de aterros sanitários mais antigos, com matéria orgânica mais estabilizada, apresentam grande potencial poluidor, principalmente devido à presença de substâncias recalcitrantes que, usualmente, não são removidas através de tratamento biológico, necessitando, portanto, da aplicação de um pós-tratamento. A presente pesquisa objetivou aplicar o tratamento físico-químico a dois efluentes de sistemas biológicos de tratamento. O primeiro sistema era constituído de um reator de lodo ativado operado em bateladas seqüenciais (70 Litros) cujo efluente era submetido à processo de coagulaçãofloculação usando sais de ferro e alumínio, para remoção da matéria orgânica recalcitrante. Operou-se, em paralelo, uma lagoa aerada, em escala de bancada, dimensionada para remoção da matéria orgânica biodegradável cujo efluente era submetido a processo de precipitação química para remoção de amônia, através da formação do mineral estruvita (MgNH4PO4.6H2O). Os resultados obtidos demonstraram que o cloreto férrico (FeCl3) foi o coagulante mais apropriado sob o ponto de vista econômico...

Remoção de fósforo do líquido de descarte do desaguamento do lodo de estações de tratamento de esgoto mediante precipitação de estruvita; Phosphorus removal from sludge water discharge of wastewater treatment plants by struvite precipitation

Marques, José Luciano Verçosa
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: dissertação de mestrado Formato: application/pdf
Publicado em 07/10/2010 Português
Relevância na Pesquisa
37.59%
A presente pesquisa estudou a viabilidade do emprego de sais de magnésio em estações de tratamento de esgoto sanitário visando a remoção do fósforo, bem como a produção de estruvita, mineral que pode ser utilizado diretamente no solo como fertilizante. As estações estudadas nesta pesquisa foram a Estação de Tratamento de Esgoto Sanitário de Franca-SP e a Estação de Tratamento de Esgoto Sanitário Jardim das Flores, localizada no município de Rio Claro-SP, e a Estação de Tratamento de Esgoto Sanitário Piçarrão, no município de Campinas. No caso da ETE Jardim das Flores (Rio Claro-SP), observou a possibilidade do emprego de sais de magnésio para se remover fósforo no efluente dos reatores UASB. Com ensaios de Jar-Test, atingiu-se cerca 49% de remoção de fosfato na amostra precipitada por gravidade e cerca de 90% na amostra centrifugada. No caso da ETE-Franca-SP, constatou-se, apesar do emprego de sais de magnésio não ter sido viável, verificou-se os benefícios do emprego de cloreto férrico em estações de tratamento de esgoto sanitário.; The present research studied the use of magnesium salts to remove phosphorus. With the phosphorus removal, magnesium salts, produce, as well, struvite, mineral that can be use directly on soil as fertilizer. The wastewater treatment plants objects of studies in this research was Wastewater Treatment Plant of Franca (SABESP) city Wastewater Treatment Plant of Jardim das Flores (Foz do Brasil)...

Fatores intervenientes na cristalização da estruvita para a recuperação do fósforo de esgoto.; Intervenient factors in struvite crystallization for phosphorus recovery from sewage.

Aidar, Fernando Ngan
Fonte: Biblioteca Digitais de Teses e Dissertações da USP Publicador: Biblioteca Digitais de Teses e Dissertações da USP
Tipo: dissertação de mestrado Formato: application/pdf
Publicado em 05/07/2012 Português
Relevância na Pesquisa
38.15%
O ciclo aberto que o fósforo percorre na sociedade contemporânea pode ser visto como uma das maiores falhas da sua sustentabilidade. Sendo este um elemento básico para qualquer ser vivo, é realmente incômodo pensar que todo o fósforo que percorre as diversas instâncias da sociedade (como agricultura, alimentos ou consumo humano) provém direta ou indiretamente da mineração, portanto, de uma fonte esgotável. Se algumas estimativas da duração de toda a reserva de rochas fosfatadas do planeta não estivessem beirando a casa de um século, esse tema, acerca da geração de uma fonte renovável e sustentável de P, não teria o mesmo peso. A presente pesquisa, realizada com uma visão multidisciplinar levando em conta estudos mineralógicos; agrícolas; de crescimento de cristais; formação de carapaça de crustáceos marinhos; tratamento de esgoto; termodinâmica e cinética de precipitações químicas traz à luz da realidade nacional uma discussão acerca dos parâmetros que possibilitam a recuperação do fósforo (e do nitrogênio) diretamente do esgoto. Nos últimos anos, diversas tentativas de precipitação de estruvita no Brasil não foram bem sucedidas. Por esse motivo, essa dissertação foi desenvolvida com o intuito de contribuir com uma melhor compreensão a respeito dos fenômenos envolvidos na formação e crescimento desses cristais. Para isso...

Urolitíase causada por oxalato de cálcio em felinos

Rosa, Patrícia Pisoni da
Tipo: trabalho de conclusão de graduação Formato: application/pdf
Português
Relevância na Pesquisa
27.93%
A urolitíase pode ser definida como a formação de precipitados em forma de urólitos em qualquer local das vias urinárias. A formação de cristais e cálculos tem como causa a diminuição na frequência urinária associada à supersaturação de cristaloides e mudança de pH da urina, podendo estar ligado a fatores dietéticos. A nutrição pode estar relacionada à formação, prevenção e tratamento das urolitíases. A urolitíase é uma das principais causas de doenças do trato urinário dos felinos. Uma variedade de cristaloides pode ser identificada nos urólitos, porém os mais comuns são os de estruvita e os de oxalato de cálcio. Antes de 1986, a urolitíase por oxalato de cálcio foi considerada rara em gatos. Depois daquela época, a incidência aumentou de 2% em 1984 para quase 50% em 1999. Este aumento foi associado, embora não claramente definido, com um maior consumo dietas acidificantes. As proporções voltaram a mudar em 2003 e em 2006, quando os urólitos de estruvita representaram 50% e os de oxalato de cálcio 39% dos cálculos. Embora os sinais clínicos variem conforme a localização dos cálculos, hematúria, disúria, polaquiúria e obstrução ureteral ou uretral são típicos da doença. É entre os sete e os nove anos de idade que os gatos apresentam maior risco de desenvolver cálculos de oxalato de cálcio. Gatos mais jovens apresentam mais casos de cálculos por estruvita. Os fatores predisponentes para a ocorrência de cada tipo de cálculo são diferentes...

Caracterização de cálculos renais por análise térmica

Branco, C. H. D.; Silva, A. L.; Luiz, J. M.; Mercuri, L. P.; Matos, J. R.
Fonte: Editora Unesp Publicador: Editora Unesp
Tipo: Artigo de Revista Científica Formato: 51-56
Português
Relevância na Pesquisa
27.59%
Dez amostras de cálculos renais foram estudadas por Análise Elementar de CHN (EA), Espectroscopia de Absorção no Infravermelho (IV) e Difração de raios X pelo método de Pó (XRD). O comportamento térmico das amostras foi estudado por Termogravimetria/Termogravimetria Derivada (TG/DTG) e por Calorimetria Exploratória Diferencial (DSC). Os resultados de EA, Espectroscopia de Absorção IV e XRD mostraram a presença de estruvita [NH4Mg(PO4).6H2O], apatita, oxalato de cálcio monohidratado e oxalato de cálcio dihidratado. As curvas TG e DSC permitiram classificar as amostras em dois grupos diferentes: Grupo I mostrando comportamento térmico típico de estruvita e Grupo II apresentando um perfil termoanalítico característico de mistura de oxalatos.; Ten samples of kidney stone had been studied through elemental analysis of CHN (EA), Infrared Absorption Spectroscopy and X-Ray Powder Diffraction (XRD). The thermal behavior of the samples is studied by Thermogravimetry/Derivative Thermogravimetry (TG/DTG) and Differential Scanning Calorimetry (DSC). The results of AE, IV absorption Spectroscopy and XRD showed the presence of struvite (NH4Mg [PO4].6H2O), apatite, monohydrated calcium oxalate and dihydrated calcium oxalate. The TG and DSC curves allowed to classify the samples in two different groups: Group I show typical thermal behavior of struvite and Group II present a profile thermal analytical characteristic of a mixture of calcium oxalate.

Evaluation of the hydration process of an industrial magnesia compound to obtain struvite crystals: a technique for recovering nutrients

Castro,Samuel Rodrigues; Araújo,Mahira Adna Cota; Lange,Liséte Celina
Fonte: Escola de Minas Publicador: Escola de Minas
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/03/2015 Português
Relevância na Pesquisa
37.93%
Struvite crystallization as a technique for recovering nutrients from wastewater streams has proven to be an attractive alternative to conventional treatments. The process becomes economically viable with the cost reductions related to the chemical reagents, especially magnesium ions. Thus, this study assessed the processing of a cheap and high-grade industrial magnesia compound in obtaining magnesium hydroxide slurries through a hydration reaction using different hydrating agents (magnesium acetate and sodium chloride solutions and water). The optimum hydration condition was achieved in acetate solution with a conversion rate to hydroxide about 67%. The efficiency of the obtained slurries as alternative reagents on the struvite crystallization process was evaluated in terms of the nutrient removal, NH4+-N and PO43--P. In experimental conditions of Mg2+:NH4+:PO43- ratio equal to 1.5:1.0:1.25 and pH equal to 8.5, the best results were achieved by using the magnesium hydroxide slurry obtained in acetate solution, which promoted removals of about 62% and 67% of NH4+-N and PO43--P, respectively. Finally, instrumental analysis confirmed the formation of struvite crystals in a purity degree that allows its use as a potential fertilizer.

Production of struvite from beverage waste as phosphorus source

Foletto,Edson Luiz; Santos,Wilson Roberto Barreto dos; Mazutti,Marcio Antonio; Jahn,Sérgio Luiz; Gündel,André
Fonte: ABM, ABC, ABPol Publicador: ABM, ABC, ABPol
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/02/2013 Português
Relevância na Pesquisa
37.59%
In this work was investigated the influence of pH on the synthesis of struvite using cola beverage waste as source of phosphorus. The process was operated in a batch reactor. The reaction time was 20 minutes, and the chemicals MgCl2.6H2O and NH4Cl were used in the experiment, with a molar ratio of Mg+2:NH4+:PO4(3-) = 1:1:1. The products were characterized by X-ray diffraction (XRD), atomic force microscopy (AFM), surface area (BET), thermogravimetric analysis (TGA) and infra-red (IR). From the results was verified the formation of a crystalline phase at pH 9.5, with a surface area of 6.59 m² g-1 and a particle size of about 0.25 µm.

Production of struvite from beverage waste as phosphorus source

Foletto,Edson Luiz; Santos,Wilson Roberto Barreto dos; Mazutti,Marcio Antonio; Jahn,Sérgio Luiz; Gündel,André
Fonte: ABM, ABC, ABPol Publicador: ABM, ABC, ABPol
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/02/2013 Português
Relevância na Pesquisa
37.59%
In this work was investigated the influence of pH on the synthesis of struvite using cola beverage waste as source of phosphorus. The process was operated in a batch reactor. The reaction time was 20 minutes, and the chemicals MgCl2.6H2O and NH4Cl were used in the experiment, with a molar ratio of Mg+2:NH4+:PO4(3-) = 1:1:1. The products were characterized by X-ray diffraction (XRD), atomic force microscopy (AFM), surface area (BET), thermogravimetric analysis (TGA) and infra-red (IR). From the results was verified the formation of a crystalline phase at pH 9.5, with a surface area of 6.59 m² g-1 and a particle size of about 0.25 µm.

Transitional cell carcinoma of the ureter and struvite calculi

Freitas,Danielo Garcia de; Garcia,Adriano Scaff; Freitas Filho,Osvaldo de
Fonte: Associação Paulista de Medicina - APM Publicador: Associação Paulista de Medicina - APM
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/05/1999 Português
Relevância na Pesquisa
27.27%
CONTEXT: The association of primary carcinoma of the ureter and lithiasis is extremely rare. We report a rare case of a primary carcinoma of the ureter with corariform calculus. CASE REPORT: 60-year-old phaeodermal female, reported a history of right-side nephritic colic, hyperthermia and pyuria during the past 20 years and had received treatment for urinary infections a number of times. The first clinical presentation was related to lithiasis and the tumor had not been shown up by excretory urography, cystoscopy or ultrasonography. Two months after the calculus had been eliminated, the patient began to have serious symptoms and a grade III transitional cell carcinoma of the ureter was discovered. Total nephroureterectomy and M.V.A.C. (Metotrexate + Vinblastina + Doxo Rubicina + Cisplatina) chemotherapy were tried unsuccessfully. In this report we emphasize the diagnostic difficulty caused by the concomitant presence of the two pathologies. In our opinion, the rapid evolution in this case is directly related to the high grade of the tumor.

Dissolution of infection-induced struvite bladder stones by using a noncalculolytic diet and antibiotic therapy

Rinkardt, Nancy E.; Houston, Doreen M.
Fonte: Canadian Veterinary Medical Association Publicador: Canadian Veterinary Medical Association
Tipo: text
Publicado em /10/2004 Português
Relevância na Pesquisa
27.59%
An 8-year-old, female spayed miniature schnauzer was presented for pollakiuria and gross hematuria. Infection-induced struvite urolithiasis with concurrent bacterial urinary tract infection was diagnosed. The treatment is described, followed by a brief discussion of struvite stones and their medical management.

Unusual case of foreign body-induced struvite urolithiasis in a dog.

Houston, D M; Eaglesome, H
Tipo: text
Publicado em /02/1999 Português
Relevância na Pesquisa
27.27%
A 6-year-old, castrated male dog was presented because of inappropriate urination and hematuria. Radiographs indicated a bladder stone with a sewing needle at its center. The urolith was removed and diagnosed as predominantly struvite, most likely a result of the foreign body and a urinary tract infection.

Effect of Curcumin Against Proteus mirabilis During Crystallization of Struvite from Artificial Urine

Prywer, Jolanta; Torzewska, Agnieszka
Fonte: Hindawi Publishing Corporation Publicador: Hindawi Publishing Corporation
Tipo: text
Português
Relevância na Pesquisa
27.93%
We investigated the activity of curcumin against Proteus mirabilis and the struvite crystallization in relation to urinary stones formation. In order to evaluate an activity of curcumin we performed an in vitro experiment of struvite growth from artificial urine. The crystallization process was induced by Proteus mirabilis to mimic the real urinary tract infection, which usually leads to urinary stone formation. The results demonstrate that curcumin exhibits the effect against Proteus mirabilis inhibiting the activity of urease—an enzyme produced by these microorganisms. Addition of curcumin increases the induction time and decreases the efficiency of growth of struvite compared with the absence of curcumin. Interestingly, the addition of curcumin does not affect the crystal morphology and habit. In conclusion, curcumin has demonstrated its significant potential to be further investigated for its use in the case of struvite crystallization induced for the growth by Proteus mirabilis in relation to urinary stone formation.

Ova of Dioctophyme renale in a canine struvite urolith

Whelen, Julie C.; Houston, Doreen M.; White, Carole; Favrin, Mike G.
Fonte: Canadian Veterinary Medical Association Publicador: Canadian Veterinary Medical Association
Tipo: text
Publicado em /12/2011 Português
Relevância na Pesquisa
27.27%
This report describes light and scanning electron microscopic appearance of an ovum from the giant kidney worm, Dioctophyme renale found in the nidus and stone layer of a struvite calculus. The stone had been surgically removed from the bladder of a 4-year-old spayed female mixed breed dog from northern Ontario.

Unique surface and internal structure of struvite crystals formed by Proteus mirabilis

Prywer, Jolanta; Torzewska, Agnieszka; P?oci?ski, Tomasz
Fonte: Springer-Verlag Publicador: Springer-Verlag
Tipo: text
Português
Relevância na Pesquisa
27.79%
Crystallization of struvite from artificial urine in the presence of Proteus mirabilis microorganisms depends strongly on pH value. At small value of pH, struvite yields crystals of coffin-like habit with very specific structure. The analysis using scanning electron microscopy shows that the crystals possess well-defined faces, but higher magnifications show very specific structuration as if the crystals were built from small three-dimensional subunits. The possible role of microorganisms in the formation of such a structuration is analyzed. At higher pH value, the crystals exhibit dendritic growth with main trunk and branches. Although the formation mechanism of the specific structuration as well as dendritic structures is unknown, the nature of forces for such an alignment is analyzed. The revealed porous internal structure of struvite is also analyzed. The investigations provide evidence for the importance of biological regulation in crystallization process.

Is Struvite a Prebiotic Mineral?

Gull, Maheen; Pasek, Matthew A.
Fonte: MDPI Publicador: MDPI
Tipo: text
Publicado em 29/04/2013 Português
Relevância na Pesquisa
28.02%
The prebiotic relevance of mineral struvite, MgNH4PO4·6H2O, was studied experimentally as a phosphorylating reagent and, theoretically, to understand the geochemical requirements for its formation. The effectiveness of phosphorylation by the phosphate mineral, monetite, CaHPO4, was also studied to compare to the efficiency of struvite. The experiments focused on the phosphorylation reactions of the minerals with organic compounds, such as nucleosides, glycerol and choline chloride, and heat at 75 °C for about 7–8 days and showed up to 28% phosphorylation of glycerol. In contrast, the compositional requirements for the precipitation of struvite are high ammonium and phosphate concentrations, as well as a little Ca2+ dissolved in the water. Combined, these requirements suggest that it is not likely that struvite was present in excess on the early Earth to carry out phosphorylation reactions. The present study focuses on the thermodynamic aspects of struvite formation, complementing the results given by Orgel and Handschuh (1973), which were based on the kinetic effects.

Recovery and removal of nutrients from swine wastewater by using a novel integrated reactor for struvite decomposition and recycling

Huang, Haiming; Xiao, Dean; Liu, Jiahui; Hou, Li; Ding, Li
Fonte: Nature Publishing Group Publicador: Nature Publishing Group
Tipo: text
Publicado em 11/05/2015 Português
Relevância na Pesquisa
28.02%
In the present study, struvite decomposition was performed by air stripping for ammonia release and a novel integrated reactor was designed for the simultaneous removal and recovery of total ammonia-nitrogen (TAN) and total orthophosphate (PT) from swine wastewater by internal struvite recycling. Decomposition of struvite by air stripping was found to be feasible. Without supplementation with additional magnesium and phosphate sources, the removal ratio of TAN from synthetic wastewater was maintained at >80% by recycling of the struvite decomposition product formed under optimal conditions, six times. Continuous operation of the integrated reactor indicated that approximately 91% TAN and 97% PT in the swine wastewater could be removed and recovered by the proposed recycling process with the supplementation of bittern. Economic evaluation of the proposed system showed that struvite precipitation cost can be saved by approximately 54% by adopting the proposed recycling process in comparison with no recycling method.

Struvite Crystallization of Anaerobic Digestive Fluid of Swine Manure Containing Highly Concentrated Nitrogen

Lee, Eun Young; Oh, Min Hwan; Yang, Seung-Hak; Yoon, Tae Han
Fonte: Asian-Australasian Association of Animal Production Societies (AAAP) and Korean Society of Animal Science and Technology (KSAST) Publicador: Asian-Australasian Association of Animal Production Societies (AAAP) and Korean Society of Animal Science and Technology (KSAST)
Tipo: text
Publicado em /07/2015 Português
Relevância na Pesquisa
27.79%
In this study, the optimal operation factors for struvite crystallization for removing and recovering nitrogen and phosphorus from anaerobic digestive fluid of swine manure containing highly concentrated nitrogen was determined. Every experiment for the struvite crystallization reaction was conducted by placing 1,000 mL of digestion fluid in a 2,000 mL Erlenmeyer flask at various temperatures, pH, and mixing speed. Except for special circumstances, the digestion fluid was centrifuged (10,000 rpm, 10 min) and then the supernatant was used for the experiment at room temperature and 100 rpm. The optimal mole ratio of PO43?:Mg2+ was 1:1.5, and the pH effect ranging from 9 to 11 was similar, when mixed for 1 hour. Under this condition, the removal efficiency of NH4+-N and PO43?-P was 40% and 88.6%, respectively. X-shaped crystal was observed by light and scanning electron microscopy. In addition, struvite crystal structure was confirmed through X-ray diffraction analysis.

Struvite crystallization

Tabanpour, Menachem E.; Barak, Phillip W.; Avila-Segura, Mauricio; Meyer, Juliane M.
Formato: application/pdf
Português
Relevância na Pesquisa
28.1%
The present invention provides a method and apparatus for removing phosphorus from phosphorus containing waste. In one embodiment, the method is preferably carried out by contacting the phosphorus containing waste with a non-cellular membrane and precipitating phosphorus from the waste as struvite. Another aspect of the invention includes a method of removing phosphorus from phosphorus containing sewage comprising filtrates and biosolids. The removal of phosphorus as struvite occurs in two stages as primary and secondary removal. In the primary removal process, the sewage from a dewatering unit is contacted with a first polymeric membrane reactor and the phosphorus is removed as primary struvite. Subsequently Mg is added so as promote struvite formation and the secondary removal process of struvite. In the secondary removal process, the sewage from GBT Filtrate well or Centrifuge Liquor well is contacted with a second monomolecular membrane and the phosphorus is removed as secondary struvite.