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Rigid composite materials from olive brush seed and unsaturated polyester resin

Jiménez, L.; Sibaja, M.; Alvarado, P.; Jimenez, G.; Barreiro, M.F.; Cateto, C.A.; Lopretti, M.
Fonte: Society of Plastics Engineers Publicador: Society of Plastics Engineers
Tipo: conferenceobject
Português
Relevância na Pesquisa
46.55%
A composite material using unsaturated commercial polyester resin (UPE) and olive brush seed (OBS) was prepared. OBS was treated with sodium hydroxide and maleic anhydride (MAN) and subsequently utilized in a proportion of 35 wt.% to prepare a composite material. These materials were evaluated in terms of moisture absorption, surface density, and mechanical properties such as flexure and tensile tests.

Rigid composite materials from olive brush seed and unsaturated polyester resin

Jiménez, L.; Sibaja, M.; Alvarado, P.; Jimenez, G.; Barreiro, M.F.; Cateto, C.A.; Lopretti, M.
Tipo: conferenceobject
Português
Relevância na Pesquisa
46.55%
A composite material using unsaturated commercial polyester resin (UPE) and olive brush seed (OBS) was prepared. OBS was treated with sodium hydroxide and maleic anhydride (MAN) and subsequently utilized in a proportion of 35 wt.% to prepare a composite material. These materials were evaluated in terms of moisture absorption, surface density, and mechanical properties such as flexure and tensile tests.

Mechanical caracterisation of polyester resin and corn natural fibers composite

Queijo, Luís; Rocha, João
Fonte: INEGI-INST ENGENHARIA MECANICA E GESTAO INDUSTRIAL Publicador: INEGI-INST ENGENHARIA MECANICA E GESTAO INDUSTRIAL
Tipo: conferenceobject
Português
Relevância na Pesquisa
46.55%
The use of natural fibers as reinforcement in polymer matrix composites is gaining popularity in the development of renewable products. Although glass and other synthetic fiber-reinforced plastics possess high specific strength, their fields of application are very limited because of their inherent higher cost of production. The work deals with the characteristics of fiber composites that can offer several advantages, like low cost, weight savings and relatively good mechanical properties. It focuses on the effects of corn fibers as reinforcement agents in composites. Mechanical testing was performed to qualify the reinforcement properties of the corn fibers and consequently to compare with fiberglass composites.

Mechanical caracterisation of polyester resin and corn natural fibers composite

Queijo, Luís; Rocha, João
Fonte: INEGI Publicador: INEGI
Tipo: conferenceobject
Português
Relevância na Pesquisa
46.55%
The use of natural fibers as reinforcement in polymer matrix composites is gaining popularity in the development of renewable products. Although glass and other synthetic fiber-reinforced plastics possess high specific strength, their fields of application are very limited because of their inherent higher cost of production. The work deals with the characteristics of fiber composites that can offer several advantages, like low cost, weight savings and relatively good mechanical properties. It focuses on the effects of corn fibers as reinforcement agents in composites. Mechanical testing was performed to qualify the reinforcement properties of the corn fibers and consequently to compare with fiberglass composites.

Toxicity-directed approach of polyester manufacturing industry wastewater provides useful information for conducting treatability studies

CAFFARO-FILHO, Roberto A.; MORITA, Dione M.; WAGNER, Roger; DURRANT, Lucia R.
Fonte: ELSEVIER SCIENCE BV Publicador: ELSEVIER SCIENCE BV
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
46.5%
A broader characterization of industrial wastewaters, especially in respect to hazardous compounds and their potential toxicity, is often necessary in order to determine the best practical treatment (or pretreatment) technology available to reduce the discharge of harmful pollutants to the environment or publicly owned treatment works. Using a toxicity-directed approach, this paper sets the base for a rational treatability study of polyester resin manufacturing. Relevant physical and chemical characteristics were determined. Respirometry was used for toxicity reduction evaluation after physical and chemical effluent fractionation. Of all the procedures investigated, only air stripping was significantly effective in reducing wastewater toxicity. Air stripping in pH 7 reduced toxicity in 18.2%, while in pH 11 a toxicity reduction of 62.5% was observed. Results indicated that toxicants responsible for the most significant fraction of the effluent`s instantaneous toxic effect to unadapted activated sludge were organic compounds poorly or not volatilized in acid conditions. These results led to useful directions for conducting treatability studies which will be grounded on actual effluent properties rather than empirical or based on the rare specific data on this kind of industrial wastewater. (C) 2008 Elsevier B.V. All rights reserved.; Coordination of Superior Level Staff Perfectioning (CAPES); Education Ministry of Brazil

Flow-injection spectrophotometric determination of captopril in pharmaceutical formulations using a new solid-phase reactor containing AgSCN immobilized in a polyurethane resin

Vicentini, Fernando Campanha; Suarez, Willian Toito; Cavalheiro, Eder Tadeu Gomes; Fatibello Filho, Orlando
Fonte: UNIV SAO PAULO, CONJUNTO QUIMICAS; SAO PAULO Publicador: UNIV SAO PAULO, CONJUNTO QUIMICAS; SAO PAULO
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
46.47%
A simple flow-injection analysis procedure was developed for determining captopril in pharmaceutical formulations employing a novel solid-phase reactor containing silver thiocyanate immobilized in a castor oil derivative polyurethane resin. The method was based on silver mercaptide formation between the captopril and Ag(I) in the solid-phase reactor. During such a reaction, the SCN- anion was released and reacted with Fe3+, which generated the FeSCN2+ complex that was continuously monitored at 480 nm. The analytical curve was linear in the captopril concentration range from 3.0 x 10(-4) mol L-1 to 1.1 x 10(-3) mol L-1 with a detection limit of 8.0 x 10(-5) mol L-1. Recoveries between 97.5% and 103% and a relative standard deviation of 2% for a solution containing 6.0 x 10(-4) mol L-1 captopril (n = 12) were obtained. The sample throughput was 40 h(-1) and the results obtained for captopril in pharmaceutical formulations using this procedure and those obtained using a pharmacopoeia procedure were in agreement at a 95% confidence level.; Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq); Conselho Nacional de Desenvolvimento Cientifico e Tecnologico (CNPq); Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES); Coordenacao de Aperfeicoamento de Pessoal de Nivel Superior (CAPES); Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP); Fundacao de Amparo a Pesquisa do Estado de Sao Paulo (FAPESP)

Influência de bebidas e escovação nas propriedades físicas de uma resina composta; Influence of beverages and brushing on the physical properties of a composite resin

Lepri, Cesar Penazzo
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 23/01/2009 Português
Relevância na Pesquisa
46.56%
Objetivo: Este estudo avaliou a influência de bebidas e escovação na estabilidade de cor, rugosidade superficial e microdureza em profundidade de uma resina composta. Materiais e Método: 120 discos (10mm de diâmetro X 2mm de espessura) de resina composta (Filtek- Z250) foram preparados e polidos após 24 horas. A cor inicial e a rugosidade superficial inicial foram mensuradas e os espécimes foram divididos aleatoriamente em quatro grupos (vinho tinto, refrigerante, aguardente, ou saliva artificial controle) e três subgrupos (sem escovação; escovação com Colgate, ou escovação com Close Up Whitening). Os espécimes foram imersos na sua respectiva solução, 5x ao dia, por 5 minutos, durante 30 dias, sendo dois subgrupos escovados ao final de cada dia (120 movimentos/dia). A cor foi mensurada no 15º e no 30º dia de imersão; a rugosidade superficial final foi medida no 30º dia. Após o período de imersão, os espécimes foram armazenados em saliva artificial por 7 dias, quando a superfície dos mesmos foi polida e imediatamente realizou-se uma mensuração de cor. A alteração de cor foi mensurada com um espectrocolorímetro e analisada pelos valores de ?E, ?L, ?a, e ?b. Os valores de rugosidade (Ra-?m) foram medidos com um rugosímetro. Com relação à microdureza...

Clinical evaluation of proximal contacts of Class II esthetic direct restorations

Prakki, Anuradha; Cilli, Renato; Saad, João Otávio Chalup; Rodrigues, José Roberto
Tipo: Artigo de Revista Científica Formato: 785-789
Português
Relevância na Pesquisa
36.95%
Objective: This study evaluated the effectiveness of proximal contacts in Class II restorations using two types of matrix bands (steel and polyester) with two different restoration techniques (incremental and with prepolymerized particles). Method and materials: Eighty-eight Class II adjacent restorations using Prodigy resin composite were performed: 44 with the incremental technique (22 with steel matrix bands, 22 with polyester matrix bands) and 44 utilizing prepolymerized resin particles (22 steel matrix, 22 polyester matrix). The restorations were clinically evaluated at baseline and at 6, 12, and 18 months. Proximal contacts obtained immediately after restoration procedure in all restorations were satisfactory. Results: No statistically significant alterations were found in 18 months of evaluation. Conclusion: Regardless of the utilized resin composite, there were no differences in the amount of proximal contact variations with respect to tested techniques and matrices.

Avaliação e identificação de toxicidade em efluente da fabricação de resinas de poliester.; Toxicity identification evaluation of polyester resin manufacturing wastewater.

Roberto Augusto Caffaro Filho
Fonte: Biblioteca Digital da Unicamp Publicador: Biblioteca Digital da Unicamp
Tipo: Tese de Doutorado Formato: application/pdf
Publicado em 05/06/2008 Português
Relevância na Pesquisa
66.91%
Os processos industriais são geradores de uma ampla variedade de contaminantes que estão presentes nas águas residuarias. A seleção de processos de tratamento baseia-se nas características do efluente a ser tratado. Neste trabalho investigou-se um efluente tóxico da fabricação de resinas de poliéster. Existem poucas informações na literatura sobre este tipo de água residuaria. Procedeu-se a caracterização do efluente, efetuando-se a avaliação e identificação de constituintes tóxicos presentes no mesmo por meio de uma abordagem orientada por toxicidade. Foi utilizado bioensaio respirometrico em lodo ativado para avaliar a toxicidade do efluente bruto. Então, foram efetuados tratamentos físicos e químicos para fracionamento do efluente, e apos cada um deles, realizou-se o mesmo bioensaio. Dessa maneira, avaliou-se qual técnica de fracionamento foi a mais efetiva na redução da toxicidade. A maior redução de toxicidade foi observada apos o fracionamento do efluente por arraste com ar em pH 11 (62,5 %). Este resultado demonstrou que uma fração significativa da toxicidade do efluente para lodos ativados era causada por compostos orgânicos volatilizados em pH 11. Isso indica que o tratamento do efluente por arraste com ar em pH básico pode ter impacto positivo em um tratamento biológico aeróbio subseqüente. Uma vez determinado o tipo de compostos no efluente que provocam efeitos tóxicos (Compostos Organicos Volateis - COVs)...

Toxicity-directed approach of polyester manufacturing industry wastewater provides useful information for conducting treatability studies

CAFFARO-FILHO, Roberto A.; MORITA, Dione M.; WAGNER, Roger; DURRANT, Lucia R.
Fonte: ELSEVIER SCIENCE BV Publicador: ELSEVIER SCIENCE BV
Tipo: Artigo de Revista Científica
Português
Relevância na Pesquisa
46.5%
A broader characterization of industrial wastewaters, especially in respect to hazardous compounds and their potential toxicity, is often necessary in order to determine the best practical treatment (or pretreatment) technology available to reduce the discharge of harmful pollutants to the environment or publicly owned treatment works. Using a toxicity-directed approach, this paper sets the base for a rational treatability study of polyester resin manufacturing. Relevant physical and chemical characteristics were determined. Respirometry was used for toxicity reduction evaluation after physical and chemical effluent fractionation. Of all the procedures investigated, only air stripping was significantly effective in reducing wastewater toxicity. Air stripping in pH 7 reduced toxicity in 18.2%, while in pH 11 a toxicity reduction of 62.5% was observed. Results indicated that toxicants responsible for the most significant fraction of the effluent`s instantaneous toxic effect to unadapted activated sludge were organic compounds poorly or not volatilized in acid conditions. These results led to useful directions for conducting treatability studies which will be grounded on actual effluent properties rather than empirical or based on the rare specific data on this kind of industrial wastewater. (C) 2008 Elsevier B.V. All rights reserved.; Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES)

Caracterização da exposição e eventuais efeitos para a saúde da exposição profissional ao estireno nos ortoprotésicos

Catarino, Filipe Miguel dos Santos
Tipo: info:eu-repo/semantics/masterthesis
Publicado em //2012 Português
Relevância na Pesquisa
46.55%
Mestrado em Segurança e Higiene do Trabalho.; Com o presente trabalho pretende definir-se um protocolo de estudo que permita a avaliação da exposição ao estireno e dos efeitos para a saúde no ortoprotésico. Constituíram ainda objectivos do presente estudo, conhecer as actividades que envolvem exposição ao estireno, conhecer a maior via de exposição e identificar os potenciais efeitos para a saúde associados com a exposição a este agente químico e caracterizar a exposição e eventuais efeitos para a saúde da exposição profissional a estireno nos Ortoprotésicos. O estireno é um solvente orgânico amplamente usado na indústria, particularmente no fabrico de polímeros, plásticos reforçados e em várias actividades de laminação. As resinas poliéster são compostas por uma percentagem elevada de estireno. A exposição ocupacional a este produto ocorre principalmente por inalação. Posteriormente é metabolizado pelo fígado em ácidos mandélico e fenilglioxílico, que são excretados pela urina. Tal como outros solventes orgânicos, o estireno é tóxico para o sistema nervoso central e é classificado como possível cancerígeno. No âmbito da monitorização ambiental e biológica, foram identificados em vários estudos...

DOT-ELISA for detection of anti-Cysticercus cellulosae antibodies in human cerebrospinal fluid using a new solid-phase (resin-treated polyester fabrics): preliminary report

Vaz,Adelaide José; Ferreira,Antonio Walter; Camargo,Mário E.; Nakamura,Paulo Mutuko; Camargo,Eide Dias
Fonte: Instituto de Medicina Tropical Publicador: Instituto de Medicina Tropical
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/10/1990 Português
Relevância na Pesquisa
46.84%
A dot enzyme-linked immunosorbent assay (DOT-ELISA) was developed to detect specific antibodies in cerebrospinal fluid (CSF) for human neurocysticercosis immunodiagnosis, with Cysticercus cellulosae antigen dotted on a new solid-phase. This was represented by sheets of a synthetic polyester fabric impregnated with a polymerized resin (N-methylol-acrylamide). A very stable preparation was thus obtained, the antigen being covalently bound by cross-linking with free N-methylol groups on the resin. Since robust, no special care was necessary for handling the solid-phase. The test could be performed at room-temperature. From 30 CSF samples assayed, 14 were positive, from a group of 15 cases of neurocysticercosis, with titers from 1 to 128; 15 other samples, from normals or other neurological diseases, were all negative. Test characteristics seem to indicate it as adequate for epidemiological surveys. A more detailed study on sensitivity, specificity, reproducibility and the use in serum samples is being conducted.

Dot-ELISA-IgM in saliva for the diagnosis of human leptospirosis using polyester fabric-resin as support (Preliminary Report)

Silva,Marcos Vinicius da; Nakamura,Paulo Mutuko; Camargo,Eide Dias; Batista,Luíza; Vaz,Adelaide José; Brandão,Angela Pires; Ferreira,Antonio Walter
Fonte: Instituto de Medicina Tropical Publicador: Instituto de Medicina Tropical
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/10/1994 Português
Relevância na Pesquisa
46.78%
In order to improve the diagnosis of human leptospirosis, we standardized the dot-ELISA for the search of specific IgM antibodies in saliva. Saliva and serum samples were collected simultaneously from 20 patients with the icterohemorrhagic form of the disease, from 10 patients with other pathologies and from 5 negative controls. Leptospires of serovars icterohaemorrhagiae, canicola, hebdomadis, brasiliensis and cynopteri grown in EMJH medium and mixed together in equal volumes, were used as antigen at individual protein concentration of 0.2 µg/µl. In the solid phase of the test we used polyester fabric impregnated with N-methylolacrylamide resin. The antigen volume for each test was 1µl, the saliva volume was 8 µl, and the volume of peroxidase-labelled anti-human IgM conjugate was 30 µl. A visual reading was taken after development in freshly prepared chromogen solution. In contrast to the classic nitrocellulose membrane support, the fabric support is easy to obtain and to handle. Saliva can be collected directly onto the support, a fact that facilitates the method and reduces the expenses and risks related to blood processing.

Construction of 2D transparent micromodels in polyester resin with porosity similar to carrots

Díaz,Rodrigo Emilio; Acuña,Sergio Miguel; Segura,Luis Andrés
Fonte: Sociedade Brasileira de Ciência e Tecnologia de Alimentos Publicador: Sociedade Brasileira de Ciência e Tecnologia de Alimentos
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2011 Português
Relevância na Pesquisa
46.91%
Microscopic visualization, especially in transparent micromodels, can provide valuable information to understand the transport phenomena at pore scale in different process occurring in porous materials (food, timber, soils, etc.). Micromodels studies focus mainly on the observation of multi-phase flow, which presents a greater proximity to reality. The aim of this study was to study the process of flexography and its application in the manufacture of polyester resin transparent micromodels and its application to carrots. Materials used to implement a flexo station for micromodels construction were thermoregulated water bath, exposure chamber to UV light, photosensitive substance (photopolymer), RTV silicone polyester resin, and glass plates. In this paper, data on size distribution of a particular kind of carrot we used, and a transparent micromodel with square cross-section as well as a Log-normal pore size distribution with pore radii ranging from 10 to 110 µm (average of 22 µm and micromodel size of 10 × 10 cm) were built. Finally, it stresses that it has successfully implemented the protocol processing 2D polyester resin transparent micromodels.

Simultaneous differential pulse voltammetric determination of L-dopa and carbidopa in pharmaceuticals using a carbon paste electrode modified with lead dioxide immobilized in a polyester resin

Melo,Hélio Corrêa de; Seleghim,Ana Paula D.; Polito,Wagner Luiz; Fatibello-Filho,Orlando; Vieira,Iolanda C.
Fonte: Sociedade Brasileira de Química Publicador: Sociedade Brasileira de Química
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/01/2007 Português
Relevância na Pesquisa
46.55%
A carbon paste electrode modified with lead dioxide immobilized in a polyester resin has been developed for simultaneous differential pulse voltammetric determination of L-dopa and carbidopa in pharmaceutical formulations. The analytical curves were linear in the concentration ranges from 2.6 ´ 10-4 to 1.2 ´ 10-3 mol L-1 and from 3.2 ´ 10-5 to 1.5 ´ 10-4 mol L-1 for L-dopa and carbidopa, respectively. The detection limits were 2.5 ´ 10-5 mol L-1 and 3.7 ´ 10-6 mol L-1 for L-dopa and carbidopa, respectively and recoveries of L-dopa and carbidopa from two samples ranged from 98.1 to 103% of the added amount. The relative standard deviations were lower than 2.5% for 1.2 ´ 10-4 and 1.2 ´ 10-3 mol L-1 of these catecholamines solutions and the results obtained for L-dopa and carbidopa in pharmaceutical formulations using the proposed voltammetric procedure are in close agreement with the labeled values and/or those obtained using an enzymatic method at the 95% confidence level.

Fiberglass wastes/polyester resin composites: mechanical properties and water sorption

Araújo,Edcleide M.; Araújo,Kasselyne D.; Pereira,Osanildo D.; Ribeiro,Pollyana C.; Melo,Tomás J. A. de
Fonte: Associação Brasileira de Polímeros Publicador: Associação Brasileira de Polímeros
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2006 Português
Relevância na Pesquisa
56.85%
The mechanical properties of polyester/fiberglass composites were studied. The aim of this work was to evaluate the possibility of reusing the wastes taken from spray-up processing of Paraíba state Industries as reinforcement in polyester matrix composites. Composites with 20, 30, 40, 50 and 60 wt. (%) of recycled fiberglass were prepared by compression molding and compared with polyester/ virgin glass fiber composites. The mechanical properties and water sorption behavior were evaluated. The results showed that fiberglass wastes are promising to be reused in polyester resin composites. The impact strength was excellent. It can be concluded that the reusing of the fiberglass wastes is viable.

Influence of glass and sisal fibers on the cure kinetics of unsaturated polyester resin

Pistor,Vinicius; Soares,Silvia Simone da Silva dos Santos; Ornaghi Júnior,Heitor Luiz; Fiorio,Rudinei; Zattera,Ademir José
Fonte: ABM, ABC, ABPol Publicador: ABM, ABC, ABPol
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2012 Português
Relevância na Pesquisa
47.04%
The effect of grinded glass and sisal fibers (25 vol%) on the cure kinetics of composites of unsaturated polyester resin (UPR) was investigated by differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). The DSC analysis was carried out at four different heating rates (5, 10, 20 and 40 °C/min), and the cure enthalpy and activation energy (Ea) were determined according to the Flynn-Wall-Ozawa (FWO) method. The results showed that increasing heating rates promoted reduced reaction times. The sisal fiber-containing composites exhibit higher activation energy values for the cure process in comparison with the neat polyester resin and the glass fiber composites. This can be due to the presence of polar groups in the sisal components, which physically interact with the polyester resin and retard the cure reaction. Hence, as sisal fiber retarded the cure reaction of the UPR resin, it is suggested that the use of natural fibers in polymer matrix composites can affect the cure kinetics of the polyester resin.

Influence of glass and sisal fibers on the cure kinetics of unsaturated polyester resin

Pistor,Vinicius; Soares,Silvia Simone da Silva dos Santos; Ornaghi Júnior,Heitor Luiz; Fiorio,Rudinei; Zattera,Ademir José
Fonte: ABM, ABC, ABPol Publicador: ABM, ABC, ABPol
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/08/2012 Português
Relevância na Pesquisa
47.04%
The effect of grinded glass and sisal fibers (25 vol%) on the cure kinetics of composites of unsaturated polyester resin (UPR) was investigated by differential scanning calorimetry (DSC) and scanning electron microscopy (SEM). The DSC analysis was carried out at four different heating rates (5, 10, 20 and 40 °C/min), and the cure enthalpy and activation energy (Ea) were determined according to the Flynn-Wall-Ozawa (FWO) method. The results showed that increasing heating rates promoted reduced reaction times. The sisal fiber-containing composites exhibit higher activation energy values for the cure process in comparison with the neat polyester resin and the glass fiber composites. This can be due to the presence of polar groups in the sisal components, which physically interact with the polyester resin and retard the cure reaction. Hence, as sisal fiber retarded the cure reaction of the UPR resin, it is suggested that the use of natural fibers in polymer matrix composites can affect the cure kinetics of the polyester resin.

Square-wave voltammetric determination of rutin in pharmaceutical formulations using a carbon composite electrode modified with copper (II) phosphate immobilized in polyester resin

Freitas,Kellen Heloizy Garcia; Fatibello-Filho,Orlando; Mattos,Ivanildo Luiz de
Fonte: Universidade de São Paulo, Faculdade de Ciências Farmacêuticas Publicador: Universidade de São Paulo, Faculdade de Ciências Farmacêuticas
Tipo: Artigo de Revista Científica Formato: text/html
Publicado em 01/12/2012 Português
Relevância na Pesquisa
46.55%
A carbon composite electrode modified with copper (II) phosphate immobilized in a polyester resin (Cu3(PO4)2-Poly) for the determination of rutin in pharmaceutical samples by square-wave voltammetry is described herein. The modified electrode allows the determination of rutin at a potential (0.20 V vs. Ag/AgCl (3.0 mol L-1 KCl)) lower than that observed at an unmodified electrode. The peak current was found to be linear to the rutin concentration in the range from 9.9 × 10-8 to 2.5 × 10-6 mol L-1, with a detection limit of 1.2×10-8 mol L-1. The response of the electrode was stable, with no variation in baseline levels within several hours of continuous operation. The surface morphology of the modified electrode was characterized by scanning electron microscopy (SEM) and energy dispersive X-ray (EDX) system. The results obtained are precise and accurate. In addition, these results are in agreement with those obtained by the chromatographic method at a 95% confidence level.

Polyester Resin Hazards

Bourne, L. B.; Milner, F. J. M.
Tipo: text
Publicado em /04/1963 Português
Relevância na Pesquisa
46.68%
Polyester resins are being increasingly used in industry. These resins require the addition of catalysts and accelerators. The handling of polyester resin system materials may give rise to skin irritations, allergic reactions, and burns. The burns are probably due to styrene and organic peroxides. Atmospheric pollution from styrene and explosion and fire risks from organic peroxides must be prevented. Where dimethylaniline is used scrupulous cleanliness and no-touch technique must be enforced. Handling precautions are suggested.