Topic
Acetone
About: Acetone is a research topic. Over the lifetime, 9458 publications have been published within this topic receiving 120867 citations. The topic is also known as: propanone & dimethylketone.
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TL;DR: In this article, the separation of different vegetable oil/solvent mixtures with two types of nanofiltration membranes was studied, one having a PEBAX [poly(amide-b-ether) copolymer] top layer and the other having a cellulose-type top layer.
Abstract: The separation of different vegetable oil/solvent mixtures with two types of nanofiltration membranes was studied. One type had a PEBAX [poly(amide-b-ether) copolymer] top layer, and the other had a cellulose-type top layer. These membranes were stable in acetone, ethanol, 2-propanol, and hexane, all important to the oleochemical industry. Permeabilities were highest for acetone, ±140 L/m2 · h · MPa, and lowest for hexane, which had negligible flux at 2 MPa. Permeabilities decreased with increasing triglyceride or free fatty acid (FFA) concentration. Rejection of triglycerides was constant over the concentration range tested, about 80–95%±5%, depending on the type of membrane used. These properties make membranes applicable for separating triglycerides from acetone by enhancing acetone recovery. Deacidification of triglycerides and FFA mixtures was possible (e.g., fatty acids were retained less than triglycerides). The permeate consisted almost entirely of fatty acids in acetone, and only small traces of triglycerides were found. This makes it feasible to selectively remove the fatty acids and reduce loss of triglycerides normally associated with deacidification.
104 citations
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104 citations
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TL;DR: It is found that the visibility of structural details was optimal with acetone and that extraction increased with both increasing and decreasing solvent polarity, and the addition of water to polar solvents increased the sample quality, while being destructive when added to apolarsolvents.
Abstract: Summary
High-pressure freezing followed by freeze substitution and plastic embedding is becoming a more widely used method for TEM sample preparation. Here, we have investigated the influence of solvents, fixative concentrations and water content in the substitution medium on the sample quality of high-pressure frozen, freeze-substituted and plastic embedded mammalian cell culture monolayers. We found that the visibility of structural details was optimal with acetone and that extraction increased with both increasing and decreasing solvent polarity. Interestingly, the addition of water to polar solvents increased the sample quality, while being destructive when added to apolar solvents. The positive effect of water addition is saturable in acetone and ethanol at 5%(v/v), but even addition of up to 20% water has no negative effect on the sample structure. Therefore, a medium based on acetone containing fixatives and 5% water is most optimal for the substitution of mammalian cell cultures. In addition, our results suggest that the presence of water is critical for the retention of structure at temperatures around –60°C.
103 citations
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TL;DR: Cerium dioxide was used as reactive sorbent for the degradation of the organophosphate pesticides parathion methyl, chlorpyrifos, dichlofenthion, fenchlorphos, and prothiofos, as well as of some chemical warfare agents as mentioned in this paper.
103 citations
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TL;DR: A comparison with 10 usual antioxidants indicated that oligomers with three or more (epi)catechin units are by far the most efficient, even expressed in relative monomeric efficiency units.
Abstract: Of three different solvents (acetone, ethanol, and methanol) mixed with water and acetic acid, the acetone/water/acetic acid mixture (70:28:2, v/v) proved to be best for extracting dark-chocolate procyanidins. High-performance liquid chromatography coupled with electrospray ionization mass spectrometry (HPLC-MS-ESI) was further used to identify oligomers found in the extract. After HPLC fraction collection, the reduction power of flavanoid fractions was measured in the AAPH [2,2'-azobis(2-amidinopropane)dihydrochloride] assay, where oxidation of linoleic acid is induced in an aqueous dispersion. Even expressed in relative monomeric efficiency units, the oxidation-inhibiting power of polymerized oligomers is much stronger than that of monomers. A comparison with 10 usual antioxidants indicated that oligomers with three or more (epi)catechin units are by far the most efficient.
103 citations