Gas Liquid
Mostrando 1-12 de 1224 artigos, teses e dissertações.
-
1. Innovative gas chromatographic determination of formaldehyde by miniaturized extraction and on-fiber derivatization, via SPME and SPME Arrow
Formaldehyde (FA) is a carbonyl compound, ubiquitous in the environment and among the most widespread pollutants: it has exhibited toxic properties and is classified as a human carcinogen. FA is released from several sources, both temporary (e.g., combustion processes) and permanent (e.g., building products). This work proposes an innovative fully-automated
Química Nova. Publicado em: 2022
-
2. Phytocomponents, Evaluation of Anticholinesterase Activity and Toxicity of Hydroethanolic Extracts of Parkia platycephala Benth.
This study evaluated the chemical composition, antioxidant and anticholinesterase activities, and the toxicity of hydroethanolic extracts of the Parkia platycephala Benth. Hot extraction with 70% hydroethanolic solution was used to obtain crude extracts of the leaf (LE), bark (BE), flower (FE), and seed (SE). Separation and identification of the compounds we
Journal of the Brazilian Chemical Society. Publicado em: 2022
-
3. A SIMPLE AND SENSITIVE LC-MS/MS METHOD FOR THE DETERMINATION OF S-PHENYLMERCAPTURIC ACID IN HUMAN URINE
Benzene is an important environmental and occupational pollutant, and recognized as human carcinogen. S-phenylmercapturic acid (SPMA) is a highly specific biomarker of exposure to benzene, applied in occupational toxicology to assess low levels of benzene exposure. The objective of this study was to develop and validate a one-step liquid extraction bioanalyt
Quím. Nova. Publicado em: 2021-03
-
4. Liquid-phase RTD studies in a flotation column: an analysis between tanks-in-series and axial dispersion models
Abstract The objective of the present study is to evaluate the fluid dynamics of a flotation column (2" in diameter and 6 m in height) based on gas hold-up measurements and, in particular, by applying the liquid-phase RTD (residence time distribution) technique. Additionally, a comparative study is performed between different methodologies used to determine
REM, Int. Eng. J.. Publicado em: 2021-01
-
5. A Simple and Efficient Optimized Solid-Liquid Extraction with Low Temperature Partition Procedure for Dissipation and Translocation Study of Pesticide Residues in Rice Grains
Pesticides are used globally to protect food against pest attack. This study evaluates the dissipation of bifenthrin and deltamethrin residues in unhulled rice and the translocation of these insecticide residues in husked rice stored at 25 °C in a biochemical oxygen demand (BOD) incubator for 35 days. For pesticide determination, the simple and efficient so
J. Braz. Chem. Soc.. Publicado em: 2020-10
-
6. Comparative study of inclusion removal from liquid steel in the RH and argon purging processes
Abstract In order to improve steel quality, it is necessary to increase the cleanliness of the liquid steel; that is, to reduce the number and size of the inclusions in the liquid steel, as well as to control their chemical composition. For this purpose, processes (with different operating costs) are used, such as the bubbling of inert gas in the steel ladle
REM, Int. Eng. J.. Publicado em: 2020-09
-
7. DETERMINATION OF THE PESTICIDES IN WATER USED IN THE CULTURE AND PROCESSING OF POTATOES
The contamination of water bodies by pesticide residues through direct flow, leaching and other methods has motivated the development of analytical methods for the determination of these compounds in water. A vortex-assisted liquid-liquid microextraction method followed by gas chromatography coupled to mass spectrometry for the determination of anilazine, li
Quím. Nova. Publicado em: 2020-09
-
8. LIMONENE QUANTIFICATION BY GAS CHROMATOGRAPHY WITH MASS SPECTROMETRY (GC-MS) AND ITS EFFECTS ON HYDROGEN AND VOLATILE FATTY ACIDS PRODUCTION IN ANAEROBIC REACTORS
The inhibition effect of limonene on the organisms involved in anaerobic reactors may affect obtaining H2 in this process. Rapid and precise limonene quantification is desirable to characterize wastewaters. The objective of this research was to develop a Gas Chromatography Coupled to Mass Spectrometry (GC-MS) method to determine limonene concentration in liq
Quím. Nova. Publicado em: 20/07/2020
-
9. The Role of 18F-FDG PET/CT in Cardiac Sarcoidosis
The inhibition effect of limonene on the organisms involved in anaerobic reactors may affect obtaining H2 in this process. Rapid and precise limonene quantification is desirable to characterize wastewaters. The objective of this research was to develop a Gas Chromatography Coupled to Mass Spectrometry (GC-MS) method to determine limonene concentration in liq
Int. J. Cardiovasc. Sci.. Publicado em: 2020-07
-
10. COVID-19: Um Novo Desafio para a Cardiopatia na Gravidez
This work presents the results obtained for the gas chromatography-mass spectrometry (GC-MS) monitoring of the liquid-phase hydrodeoxygenation (HDO) reaction of furfural (FFR) to 2-methylfuran (MF) over a bifunctional Ru/RuOx/C catalyst in the presence of a direct source of H2. Hydrogenation and hydrogenolysis reactions of FFR and of the intermediate furfury
Arq. Bras. Cardiol.. Publicado em: 2020-07
-
11. Furfural Hydrodeoxygenation over a Ruthenium-Based Bifunctional Catalyst in the Presence of a Direct Source of H2
This work presents the results obtained for the gas chromatography-mass spectrometry (GC-MS) monitoring of the liquid-phase hydrodeoxygenation (HDO) reaction of furfural (FFR) to 2-methylfuran (MF) over a bifunctional Ru/RuOx/C catalyst in the presence of a direct source of H2. Hydrogenation and hydrogenolysis reactions of FFR and of the intermediate furfury
J. Braz. Chem. Soc.. Publicado em: 2020-07
-
12. Determination and Risk Assessment of Formaldehyde and Acetaldehyde in the Ambient Air of Gas Stations in Salvador, Bahia, Brazil
Formaldehyde (FA) and acetaldehyde (AA) were determined in the ambient air of five gas stations (GS) in the city of Salvador, Bahia State, Brazil, using three passive samplers exposed simultaneously for 8 h and analysis by high-performance liquid chromatography-ultraviolet detection (HPLC-UV). The concentration ranges found were 3.31-5.78 µg m−3 for FA an
J. Braz. Chem. Soc.. Publicado em: 2020-06