Molar Mass
Mostrando 1-12 de 230 artigos, teses e dissertações.
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1. PLANEJAMENTO FATORIAL NA SÍNTESE DO OLEATO DE ETILA CATALISADA PELA LIPASE NATIVA DE Aspergillus niger
This work reports the use of the Octave, a free computational software, to optimize the experimental design in the synthesis of ethyl oleate from oleic acid and ethanol catalyzed by a native lipase from Aspergillus niger. The central composite factorial design (CCD) was performed with 2 levels and 3 variables (temperature, mass of native A. niger lipase and
Química Nova. Publicado em: 2022
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2. Extraction and Characterization of Pequi Seed Oil for Biodiesel Production: A Green Management of Waste to Biofuel Using Ethanol and Heterogeneous Catalysis
This work reports the characterization of a vegetable oil extracted from pequi seeds, an agroindustrial residue, and its biodiesel production using ethanol and heterogeneous catalysis. The pequi seeds showed 40.73 wt.% of extractive content, which represents a large amount of the biomass composition. The crude oil extracted from the pequi seeds with ethanol
Journal of the Brazilian Chemical Society. Publicado em: 2022
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3. A Greener Enzymatic Oligoesterification of Biobased Renewable Synthons
Polyesters of xylitol and succinic acid were prepared yielding from 70 to 75% by enzyme-catalyzed esterification using a molar mass from 1:1 to 2:5 at 120 and 140 °C employing from 1 to 10% m/m of enzyme. Control over branching degree was achieved by tuning the reaction conditions (temperature, time, comonomer ratio, enzyme content). This one-step process f
J. Braz. Chem. Soc.. Publicado em: 2021-06
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4. MACROALGAE Fucus vesiculosus OIL: BIODIESEL PRODUCTION USING ALKALINE TRANSESTERIFICATION
This work studied the obtaining of methyl biodiesel and ethyl biodiesel using alkaline transesterification from macroalgae Fucus vesiculosos oil (FVO). FVO has 86.59% of its composition in unsaturated fatty acids, with a greater quantity of linoleic acid and oleic acid, a chemical composition near the soybean oil, the most used raw material for the productio
Quím. Nova. Publicado em: 2021-04
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5. Inhibition of Acetylcholinesterase by Coumarin-Linked Amino Acids Synthetized via Triazole Associated with Molecule Partition Coefficient
A previous study for the identification of acetylcholinesterase (AChE) inhibitors demonstrated that the hybrid between tyrosol, the 1,2,3-triazole nucleus, and the coumarin group, namely 7-({1-[2-(4-hydroxyphenyl)ethyl]-1H-1,2,3-triazol-4-yl}methoxy)-4-methyl-2H-chromen-2-one (10), has a high enzyme inhibitory activity. Here, we synthesized analogues of 10 v
J. Braz. Chem. Soc.. Publicado em: 2021-03
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6. Method for Cleaning Back-Produced Water from Polymer Flooding Operations to Determine Polymer Molar Mass Using Size-Exclusion Chromatography
One of the methods used by the oil industry to increase production is to inject water, containing polymer, into the reservoir. The viscosity of the aqueous solution is primarily responsible for the efficiency of this method, and is achieved using polymers with high molar mass. However, polymer degradation can occur during pumping and fluid displacement in th
J. Braz. Chem. Soc.. Publicado em: 2020-12
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7. Is it still worth Publishing Case Reports? They are Part of our Lives
Partially hydrogenated soybean oil and palm olein are oils that are widely used in the food industry. Continuous contact with air may cause changes of the triglycerides chemical structure, to eventually produce substances of lower molar masses that may be toxic to mammals. This study aimed to determine the kinetic parameters for the thermal oxidation of thes
Braz. J. Cardiovasc. Surg.. Publicado em: 2020-10
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8. Kinetic Parameters of the Thermal Oxidation and Degradation Reactions in Soybean Oil and Palm Olein
Partially hydrogenated soybean oil and palm olein are oils that are widely used in the food industry. Continuous contact with air may cause changes of the triglycerides chemical structure, to eventually produce substances of lower molar masses that may be toxic to mammals. This study aimed to determine the kinetic parameters for the thermal oxidation of thes
J. Braz. Chem. Soc.. Publicado em: 2020-10
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9. IN SITU DRIFTS/MS STUDIES ON THE INTERACTION OF METHANOL AND ETHYL ACETATE OVER MG-LA CATALYST
The surface intermediates formed on the Mg-La catalyst (molar ratio 1:1) were studied through temperature-programmed desorption (TPD) and diffuse reflectance infrared Fourier transform spectroscopy coupled to mass spectrometry (DRIFTS-MS) using methanol (MeOH) and ethyl acetate (EA) as probe molecules. TPD results showed that the products formed from adsorbe
Quím. Nova. Publicado em: 2020-09
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10. PREPARATION AND SIMULATION OF THE ON-LINE SiO2/S COATING FOR COKING INHIBITION IN THE INDUSTRIAL CRACKING FURNACE
Abstract Coke formation inside radiant coils is one of the main problems during thermal cracking of hydrocarbons. The on-line preparation of the coating for coking inhibition is a promising technology because it provides more flexibility to the operators on site. The SiO2/S coating was prepared on the inner surface of coils in an 8-year-served GK-VI industri
Braz. J. Chem. Eng.. Publicado em: 13/01/2020
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11. EFFECT OF CYCLOPENTANE HYDRATES ON THE STABILITY OF DODAC AND AOT STRUCTURES
Abstract Hydrates are crystalline structures formed by water and substances with low molar mass molecules. Hydrate formation can occur during oil production when oil, gas and water flow through the same lines in conditions of high pressure and low temperatures. The deposition of hydrate crystals in production lines can severely jeopardize the safety of oper
Braz. J. Chem. Eng.. Publicado em: 13/01/2020
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12. Application of Glycerol in the Synthesis of Hyperbranched and Highly Branched Polyethers: Characterization, Morphology and Mechanism Proposal
Hyperbranched biopolymers is an important class of polymer that is used in different areas, mainly in biomedicine. AB2 monomers are crucial to the development of a "hyperbranched" architecture of polyglycerol, being glycidol the most commonly used, even considering its environmental hazard. Glycerol carbonate is an ecologically accepted monomer synthesized d
Mat. Res.. Publicado em: 24/10/2019