Quechers
Mostrando 13-24 de 79 artigos, teses e dissertações.
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13. LC-MS/MS análises de inseticidas neonicotinoides: Resíduos encontrados em méis chilenos
RESUMO Os neonicotinóides são uma geração relativamente nova de inseticidas que tem sido utilizado para o controle de pragas, como pulgões, cigarrinhas e moscas brancas. Este artigo apresenta pela primeira vez a determinação de resíduos de quatro inseticidas neonicotinóides (acetamiprida, tiametoxam, tiaclopride e imidaclopride) em méis chilenos em
Ciênc. agrotec.. Publicado em: 2018-02
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14. Incidence of aflatoxin M1 in fresh milk from small farms
Abstract The objective of this work was to determine aflatoxin M1 in fresh milk from fifty-two small farms in the city of Concórdia - SC, Brazil. Samples from the cooling tanks of each property were collected from November 2014 to January 2015. The QuEChERS method was used for the extraction of aflatoxin M1, and quantification was performed in UHPLC-FL. 40.
Food Sci. Technol. Publicado em: 2017-12
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15. Evaluation of QuEChERS Sample Preparation for Determination of Avermectins Residues in Ovine Muscle by HPLC-FD and UHPLC-MS/MS
A fast and sensitive method using high performance liquid chromatography-fluorescence detection (HPLC-FD) and ultra-high performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) was developed and validated for the determination of avermectins residues in ovine muscle samples. QuEChERS (quick, easy, cheap, effective, rugged and safe) sample pr
J. Braz. Chem. Soc.. Publicado em: 2017-05
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16. Resíduos de fungicidas e inseticidas em grãos de arroz
RESUMO. O estudo objetivou analisar resíduos de fungicidas e inseticidas nos grãos de arroz submetidos a diferentes formas de processamento. O trabalho foi realizado no campo durante três safras agrícolas com a aplicação de fungicidas e inseticidas sobre a parte aérea das plantas de arroz. Foi realizado um tratamento com a aplicação dos fungicidas a
Acta Sci., Agron.. Publicado em: 2017-03
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17. Determinação de agrotóxicos na água e sedimentos por HPLC-HRMS e sua relação com o uso e ocupação do solo
In present times, the Brazil is in the middle of the largest pesticide consumers worldwide, which demands proper control of environmental contamination. This study evaluated herbicides, acaricide, insecticides and fungicides in water and sediment carried-out from Lageado Tacongava hydrographic basin, Rio Grande do Sul, Brazil. For analysis, a QuEChERS (Quick
Quím. Nova. Publicado em: 2017-02
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18. Validation of a LC-MS/MS Multiresidue Methodology Based on a QuEChERS Approach for the Determination of Fluoroquinolones, Sulfonamides and Trimethoprim in Poultry and Porcine Kidney According to the Normative Instruction 24/2009-MAPA
This work involved the validation of a multiresidue method according to the Normative Instruction 24/2009-MAPA for determining 25 analytes, among fluoroquinolones, sulfonamides and trimethoprim in samples of poultry and porcine kidney. The extraction procedure was based on a QuEChERS approach. A liquid chromatography-tandem mass spectrometry (LC-MS/MS) metho
J. Braz. Chem. Soc.. Publicado em: 2017-01
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19. Determination of Pesticides in Grape Juices by QuEChERS and Liquid Chromatography-Tandem Mass Spectrometry
In this study, we describe a liquid chromatography-tandem mass spectrometry (LC-MS/MS) method for quantifying 25 pesticides in grape juice. This method was optimized and validated according with INMETRO (Instituto Nacional de Metrologia Qualidade e Tecnologia) for the simultaneous determination of pesticide, which are widely used in grape culture in Brazil.
J. Braz. Chem. Soc.. Publicado em: 2016-09
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20. Evaluation of QuEChERS Sample Preparation and Gas Chromatography Coupled to Mass Spectrometry for the Determination of Pesticide Residues in Grapes
An effective analytical method for pesticides multiresidue determination in grape samples was developed and validated. A modified quick, easy, cheap, effective, robust and safe (QuEChERS) method was used to extract the target compounds. Several sorbent materials were tested for the clean-up step using dispersive solid phase extraction (d-SPE) and Florisil®
J. Braz. Chem. Soc.. Publicado em: 2016-09
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21. Application of a 33 Box-Behnken Design to Optimize the Extraction of Eleven Fluoroquinolones from Poultry Muscle and Kidney Using a QuEChERS Approach via Liquid Chromatography Tandem Mass Spectrometry: the Easy Use of Microsoft Excel® in Multivariate Analysis
This work presents an optimization of a quick, easy, cheap, effective, rugged and safe (QuEChERS) extraction approach of eleven fluoroquinolones in poultry muscle and kidney using a 33 Box-Behnken factorial design. All the data treatment was performed using Microsoft Excel® 2010. The suitability of the developed method was confirmed by two proficiency tests
J. Braz. Chem. Soc.. Publicado em: 2016-01
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22. Simultaneous Determination of Herbicides in Rice by QuEChERS and LC-MS/MS Using Matrix-Matched Calibration
The main objective of the present work was to validate a chromatographic method to determine herbicides commonly applied in the irrigated rice farming. For this, matrix-matched calibration was employed along with the extraction and clean-up of the samples by quick, easy, cheap, effective, rugged and safe (QuEChERS) method and determination of the analytes by
J. Braz. Chem. Soc.. Publicado em: 2016-01
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23. Monitoring of Pesticide Residues in Surface and Subsurface Waters, Sediments, and Fish in Center-Pivot Irrigation Areas
In this study, the monitoring of pesticide residues, which show potential for environmental contamination, in center-pivot irrigated areas in the Brazilian cerrado, was performed. The pesticides monitored were acephate, atrazine, azoxystrobin, buprofezin, carbofuran, cyproconazole, chlorpyrifos, difenoconazole, diuron, imidacloprid, malathion, methamidophos,
J. Braz. Chem. Soc.. Publicado em: 2015-11
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24. Effects of Types of Washing and Peeling in Relation to Pesticide Residues in Tomatoes
Tomatoes are widely consumed and most often without cooking, therefore it is important to estimate the reduction of residues using simple washing procedures. An experiment was carried out to evaluate the effects of household processing such as: washing with water, washing with 10% of vinegar solution and washing with 10% of sodium bicarbonate solution on pes
J. Braz. Chem. Soc.. Publicado em: 2015-10