Gas Mixtures
Mostrando 1-12 de 196 artigos, teses e dissertações.
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1. Quantification of Carbon Dioxide (CO2), Methane (CH4), and Nitrous Oxide (N2O) Using Near Infrared Spectroscopy and Multivariate Calibration in High Humidity Levels
In this work we developed a promising analytical method combining Fourier transform near-infrared (FT-NIR) spectroscopic technique and first-order multivariate calibration using partial least-squares (PLS) model to simultaneously quantify the main greenhouse gases (GHG’s): methane (CH4), carbon dioxide (CO2), nitrous oxide (N2O) and water vapor (H2O). The
Journal of the Brazilian Chemical Society. Publicado em: 2022
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2. Identifying olive oil fraud and adulteration using machine learning algorithms
As olive oil (OO) is more expensive than other vegetable oils, it is usually adulterated by blending it with more economic edible oils such as cottonseed oil (CSO), canola oil (CO), and soybean oil (SO). This research aimed to determine the fatty acid compositions obtained as a result of blending different proportions of CSO, CO and SO with OO using a gas ch
Química Nova. Publicado em: 2022
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3. A Selective Gas Chromatography-Selected Ion Monitoring Mass Spectrometry (GC-MS/SIM) Method to Determine Polychlorinated Biphenyls in Fuller’s Earth
Polychlorinated biphenyls (PCBs) are carcinogenic to humans and can be found in Fuller’s earth used for the regeneration of used transformer oil. This work describes a highly selective gas chromatographic-selected ion monitoring mass spectrometric method (GC-MS/SIM) for the simultaneous determination of three Aroclor PCB congener mixtures (1242, 1254, and
J. Braz. Chem. Soc.. Publicado em: 2020-03
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4. SYNTHESIS, CHARACTERIZATION, ADSORPTION AND THERMODYNAMIC STUDIES OF PURE AND BINARY CO2-N2 MIXTURES ON OXYGEN ENRICHED NANOSTRUCTURED CARBON ADSORBENTS
Abstract Oxygen enriched porous carbons have been synthesized by a nanocasting technique using mesoporous zeolite as template and epoxy resin as precursor. Characterization results show the effect of the nanocasting technique on the development of heterogeneous surface, high basicity, and high surface area of 686.37 m2g-1, beneficial for CO2 adsorption. Pure
Braz. J. Chem. Eng.. Publicado em: 09/12/2019
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5. Quantification and qualification of exhaust gases in agricultural diesel engine operating with biodiesel mixtures
RESUMO Motores de ciclo diesel são amplamente utilizados em máquinas agrícolas. O biodiesel oferece a possibilidade de substituição parcial ou total do diesel mineral, reduzindo assim a dependência da agricultura desse recurso não renovável e diminuindo as emissões de poluentes. O objetivo deste estudo foi avaliar as emissões de CO, NOx, SO2, CO2 e
Rev. bras. eng. agríc. ambient.. Publicado em: 09/09/2019
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6. LIGHT N-PARAFFINS SEPARATION BY INVERSE GAS CHROMATOGRAPHY WITH CUBAN VOLCANIC GLASS
ABSTRACT In this work the applicability of a natural volcanic glass (technological type I material) from Cuba is investigated as adsorbent for separation of mixtures of C1-(C5; C6; C7; C8; C9) hydrocarbons by inverse gas chromatography under flow conditions in a temperature range of 328-343 K. The experimental results indicated that the material was mainly
Braz. J. Chem. Eng.. Publicado em: 15/07/2019
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7. Quality of ‘Oso Grande’ strawberries is affected by O2, CO2 and N2O concentrations during controlled atmosphere storage
ABSTRACT Consumers around the world appreciate strawberries for their taste. They have low calories and high concentrations of soluble fibers, vitamin C and flavonoids. This paper verified the combined effect of O2, CO2, and N2O levels on ‘Oso Grande’ strawberries stored at 10° C, under controlled atmosphere (CA). Five different gas mixtures were used:
Bragantia. Publicado em: 18/04/2019
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8. Thermal Properties of the Blends of Methyl and Ethyl Esters Prepared from Babassu and Soybean Oils
Fatty acid esters (methyl and ethyl) prepared from babassu nut oil were blended with the respective esters from soybean oil. These binary blends (babassu:soybean) were made in proportions of 10:90, 20:80, 30:70, 40:60, and 50:50 (vol%). The ester content of all the blends was higher than 96.5%, which is the minimum value required by the Brazilian National Ag
J. Braz. Chem. Soc.. Publicado em: 2018-08
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9. Mass Spectrometry Study of Ammonia Formed During Plasma Nitrocarburizing and Nitriding Processes
In this work, we used mass spectrometry to investigate ammonia (NH3) formed during the nitrocarburizing and nitriding processes of α-Fe sintered and low alloy steel by using d.c. glow discharges in different N2/H2/CH4 gas concentration mixtures. Experiments were conducted using two different configurations: one to collect and analyze species probed primaril
Mat. Res.. Publicado em: 16/07/2018
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10. An Examination of the Prediction of Hydrate Formation Conditions in the Presence of Thermodynamic Inhibitors
Abstract Gas hydrates are crystalline compounds, solid structures where water traps small guest molecules, typically light gases, in cages formed by hydrogen bonds. They are notorious for causing problems in oil and gas production, transportation and processing. Gas hydrates may form at pressures and temperatures commonly found in natural gas and oil product
Braz. J. Chem. Eng.. Publicado em: 2018-01
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11. Evaluation of the insecticidal activity of essential oils and their mixtures against Aedes aegypti (Diptera: Culicidae)
Abstract The search for new insecticides to control dengue fever, chikungunya, and Zika vectors has gained relevance in the past decades. The aim of the present study was to evaluate the larvicidal action of essential oils (EOs) from Thymus vulgaris, Salvia officinalis, Lippia origanoides, Eucalyptus globulus, Cymbopogon nardus, Cymbopogon martinii, Lippia a
Rev. Bras. entomol.. Publicado em: 2017-12
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12. USO DA ESPECTROFOTOMETRIA UV-VIS PARA DIFERENCIAR AS COLORAÇÕES DO BIODIESEL DE PALMA E DO CORANTE MARCADOR DE ÓLEO DIESEL
Currently, there are two mixtures of biodiesel/diesel fuel sold in Brazil: BX/S500 and BX /S10 (X = volume/volume biodiesel percentage; S500 and S10 = sulfur content in diesel fuels - 500 ppm and 10 ppm, respectively). In order to differentiate these mixtures, red dye is added to diesel oil as required by the National Agency for Petroleum, Natural Gas and Bi
Quím. Nova. Publicado em: 2017-08