| |
|
|
| Registros recuperados : 220 | |
| 122. |  | PRESTES, E. B.; PAULA, V. J. de; SANTOS, F.; JONSSON, C. M.; CASTRO, V. L. S. S. de. Avaliação do efeito dos fungicidas Epoxiconazol, Piraclostrobina e sua mistura no crescimento da microalga Pseudokirchneriella subcapitata. In: CONGRESSO BRASILEIRO DE ECOTOXICOLOGIA, 11., 2010, Bombinhas. Anais... Bombinhas: Sociedade Brasileira de Ecotoxicologia, 2010. 1 CD- ROM.| Biblioteca(s): Embrapa Meio Ambiente. |
|   |
| 130. | | OLIVEIRA, L. P. de; LIMA, C. G. de; SIQUEIRA, M. C.; CASTRO, V. L. S. S. de. Ajuste de modelo heteroscedástico em estudo toxicológico usando o SAS. Revista da Estatística UFOP, Ouro Preto, v. 3, n. 3, 2014. Edição dos trabalhos apresentados como pôsteres na 59ª Reunião Anual da Regional Brasileira da Sociedade Internacional de Biometria, Ouro Preto, 2014. p. 49-53.| Biblioteca(s): Embrapa Meio Ambiente. |
|  |
| 133. | | SILVA, C. M. M. de S.; CASTRO, V. L. S. S. de; OLIVEIRA, P. R.; MAIA, A. de H. N. Influence of Pseudomonas putida AF7 inoculation on soil enzymes activities. In: IBERIAN CONGRESS OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY, 7.; IBEROAMERICAN CONGRESS OF ENVIRONMENTAL CONTAMINATION AND TOXICOLOGY, 4., 2008, Lisboa. Abstracts book. Lisboa: Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2008. p.200.| Biblioteca(s): Embrapa Meio Ambiente. |
| |
| 139. | | MEDEIROS, A. M. Z.; SILVA, G. H. da; CASTRO, V. L. S. S. de; MARTINEZ, D. S. T. Efeitos diferentes na co-exposição de óxido de grafeno e ácido húmico em zebrafish: influência do córion. In: SIMPÓSIO CIENTÍFICO DOS PÓS-GRADUANDOS DO CENA, 10., 2017, Piracicaba. Novos tempos na pesquisa: transformação, liderança e inovação: resumos... Piracicaba, SP: CENA/USP, 2017.| Biblioteca(s): Embrapa Meio Ambiente. |
| |
| Registros recuperados : 220 | |
|
|
|
Registro Completo
|
Biblioteca(s): |
Embrapa Meio Ambiente. |
|
Data corrente: |
06/04/2017 |
|
Data da última atualização: |
01/08/2017 |
|
Tipo da produção científica: |
Resumo em Anais de Congresso |
|
Autoria: |
CLEMENTE, Z.; CASTRO, V. L. S. S. de; FRANQUI, L.; SILVA, C. A.; MARTINEZ, D. S. T. |
|
Afiliação: |
ZAIRA CLEMENTE, CNPEM; VERA LUCIA SCHERHOLZ S DE CASTRO, CNPMA; LIDIANE FRANQUI, CNPEM; CRISTIANE A. SILVA, CNPEM; DIEGO STEFANI TEODORO MARTINEZ, CNPEM. |
|
Título: |
Evaluating the graphene oxide dispersions for fish embryo toxicity (FET) test. |
|
Ano de publicação: |
2016 |
|
Fonte/Imprenta: |
In: ENCONTRO ANUAL DA SOCIEDADE BRASILEIRA DE PESQUISA EM MATERIAIS, 15., 2016, Campinas. [Abstracts...] Rio de Janeiro: Sociedade Brasileira de Pesquisas em Materiais, 2016. Resumo B6E2. |
|
Idioma: |
Português |
|
Conteúdo: |
The Fish Embryo Toxicity (FET) test has wide utilization in nanoecotoxicology. However, some difficulties have been found related to the aggregation and precipitation of nanomaterials in exposure medium and the contrasting results among studies due to differences in the material characteristics. Furthermore, abiotic factors as the presence of organic matter can influence the test evaluation. The aim of this study was to evaluate and characterize the effect of the humic acid presence in the stability of two types of graphene oxide dispersion in an exposure medium used in FET test. Stock-suspensions (1.0 mg mL-1) of GO (sigma Aldrich, flakes) or base-washed GO (bwGO) and humic acid (HA sodium salt, Sigma Aldrich) were prepared in ultrapure water (UW). They were sonicated before preparing the GO or bwGO test suspensions at 100.0 µg mL-1 in UW and reconstituted water (RW, pH 8±0.2, 425±129 µS/cm), with HA (20.0 µg mL-1)or not. The samples were incubated during 96h at 26oC. The GO and bwGO and its dispersions were characterized through the following techniques: spectrophotometry, centrifugation, dynamic light scattering (DLS), nanoparticle tracking analysis (NTA), thermogravimetry (TGA), and X-ray photoelectron spectrometry (XPS). The results showed that materials aggregated and precipitated quickly in RW, but in the presence of HA the stability was similar to that found in UW. The aggregation and precipitation of bwGO was more intense than that of GO. The bwGO showed a great particle sizes heterogeneity than GO, in any condition tested. The different behavior can be related to the less presence of oxygenated groups in bwGO regards to GO. These results showed that surface characteristic of GO and the presence of HA influence the GO behavior in exposure medium and support the use of HA as a natural dispersant to graphene oxide in FET test. MenosThe Fish Embryo Toxicity (FET) test has wide utilization in nanoecotoxicology. However, some difficulties have been found related to the aggregation and precipitation of nanomaterials in exposure medium and the contrasting results among studies due to differences in the material characteristics. Furthermore, abiotic factors as the presence of organic matter can influence the test evaluation. The aim of this study was to evaluate and characterize the effect of the humic acid presence in the stability of two types of graphene oxide dispersion in an exposure medium used in FET test. Stock-suspensions (1.0 mg mL-1) of GO (sigma Aldrich, flakes) or base-washed GO (bwGO) and humic acid (HA sodium salt, Sigma Aldrich) were prepared in ultrapure water (UW). They were sonicated before preparing the GO or bwGO test suspensions at 100.0 µg mL-1 in UW and reconstituted water (RW, pH 8±0.2, 425±129 µS/cm), with HA (20.0 µg mL-1)or not. The samples were incubated during 96h at 26oC. The GO and bwGO and its dispersions were characterized through the following techniques: spectrophotometry, centrifugation, dynamic light scattering (DLS), nanoparticle tracking analysis (NTA), thermogravimetry (TGA), and X-ray photoelectron spectrometry (XPS). The results showed that materials aggregated and precipitated quickly in RW, but in the presence of HA the stability was similar to that found in UW. The aggregation and precipitation of bwGO was more intense than that of GO. The bwGO showed a great par... Mostrar Tudo |
|
Palavras-Chave: |
Ecotoxicologia; FET test. |
|
Thesagro: |
Peixe. |
|
Thesaurus NAL: |
Graphene. |
|
Categoria do assunto: |
W Química e Física |
|
URL: |
https://ainfo.cnptia.embrapa.br/digital/bitstream/item/161194/1/2016RA-041.pdf
|
|
Marc: |
LEADER 02600nam a2200205 a 4500
001 2068204
005 2017-08-01
008 2016 bl uuuu u00u1 u #d
100 1 $aCLEMENTE, Z.
245 $aEvaluating the graphene oxide dispersions for fish embryo toxicity (FET) test.$h[electronic resource]
260 $aIn: ENCONTRO ANUAL DA SOCIEDADE BRASILEIRA DE PESQUISA EM MATERIAIS, 15., 2016, Campinas. [Abstracts...] Rio de Janeiro: Sociedade Brasileira de Pesquisas em Materiais, 2016. Resumo B6E2.$c2016
520 $aThe Fish Embryo Toxicity (FET) test has wide utilization in nanoecotoxicology. However, some difficulties have been found related to the aggregation and precipitation of nanomaterials in exposure medium and the contrasting results among studies due to differences in the material characteristics. Furthermore, abiotic factors as the presence of organic matter can influence the test evaluation. The aim of this study was to evaluate and characterize the effect of the humic acid presence in the stability of two types of graphene oxide dispersion in an exposure medium used in FET test. Stock-suspensions (1.0 mg mL-1) of GO (sigma Aldrich, flakes) or base-washed GO (bwGO) and humic acid (HA sodium salt, Sigma Aldrich) were prepared in ultrapure water (UW). They were sonicated before preparing the GO or bwGO test suspensions at 100.0 µg mL-1 in UW and reconstituted water (RW, pH 8±0.2, 425±129 µS/cm), with HA (20.0 µg mL-1)or not. The samples were incubated during 96h at 26oC. The GO and bwGO and its dispersions were characterized through the following techniques: spectrophotometry, centrifugation, dynamic light scattering (DLS), nanoparticle tracking analysis (NTA), thermogravimetry (TGA), and X-ray photoelectron spectrometry (XPS). The results showed that materials aggregated and precipitated quickly in RW, but in the presence of HA the stability was similar to that found in UW. The aggregation and precipitation of bwGO was more intense than that of GO. The bwGO showed a great particle sizes heterogeneity than GO, in any condition tested. The different behavior can be related to the less presence of oxygenated groups in bwGO regards to GO. These results showed that surface characteristic of GO and the presence of HA influence the GO behavior in exposure medium and support the use of HA as a natural dispersant to graphene oxide in FET test.
650 $aGraphene
650 $aPeixe
653 $aEcotoxicologia
653 $aFET test
700 1 $aCASTRO, V. L. S. S. de
700 1 $aFRANQUI, L.
700 1 $aSILVA, C. A.
700 1 $aMARTINEZ, D. S. T.
Download
Esconder MarcMostrar Marc Completo |
|
Registro original: |
Embrapa Meio Ambiente (CNPMA) |
|
|
Biblioteca |
ID |
Origem |
Tipo/Formato |
Classificação |
Cutter |
Registro |
Volume |
Status |
Fechar
|
| Nenhum registro encontrado para a expressão de busca informada. |
|
|
