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Topic Review
Interesterified Fat
Interesterified fat is a type of oil where the fatty acids have been moved from one triglyceride molecule to another. This is generally done to modify the melting point, slow rancidification, and create an oil more suitable for deep frying or making palatable margarine with low saturated fat content. It is not the same as partial hydrogenation which produces trans fatty acids, but interesterified fats used in the food industry can come from hydrogenated fat,[clarification needed] for simplicity and frugality.
  • 882
  • 26 Oct 2022
Topic Review
N-Butanol
n-Butanol or n-butyl alcohol or normal butanol is a primary alcohol with a 4-carbon structure and the chemical formula C4H9OH. Its isomers include isobutanol, 2-butanol, and tert-butanol. Butanol is one of the group of "fusel alcohols" (from the German for "bad liquor"), which have more than two carbon atoms and have significant solubility in water. n-Butanol occurs naturally as a minor product of the fermentation of sugars and other carbohydrates, and is present in many foods and beverages. It is also a permitted artificial flavorant in the United States, used in butter, cream, fruit, rum, whiskey, ice cream and ices, candy, baked goods and cordials. It is also used in a wide range of consumer products. The largest use of n-butanol is as an industrial intermediate, particularly for the manufacture of butyl acetate (itself an artificial flavorant and industrial solvent). It is a petrochemical, manufactured from propylene and usually used close to the point of manufacture. Estimated production figures for 1997 are: United States 784,000 tonnes; Western Europe 575,000 tonnes; Japan 225,000 tonnes.
  • 2.1K
  • 26 Oct 2022
Topic Review
Optical Polymer-Based Sensors in Environmental and Biological Systems
Polymers are widely used in many areas, but often their individual properties are not sufficient for use in certain applications. One of the solutions is the creation of polymer-based composites and nanocomposites. In such materials, in order to improve their properties, nanoscale particles (at least in one dimension) are dispersed in the polymer matrix. These properties include increased mechanical strength and durability, the ability to create a developed inner surface, adjustable thermal and electrical conductivity, and many others. The materials created can have a wide range of applications, such as biomimetic materials and technologies, smart materials, renewable energy sources, packaging, etc.
  • 466
  • 26 Oct 2022
Topic Review
Cellulosic Ethanol Commercialization
Cellulosic ethanol commercialization is the process of building an industry out of methods of turning cellulose-containing organic matter into cellulosic ethanol for use as a biofuel. Companies, such as Iogen, POET, DuPont, and Abengoa, are building refineries that can process biomass and turn it into bioethanol. Companies, such as Diversa, Novozymes, and Dyadic, are producing enzymes that could enable a cellulosic ethanol future. The shift from food crop feedstocks to waste residues and native grasses offers significant opportunities for a range of players, from farmers to biotechnology firms, and from project developers to investors. As of 2013, the first commercial-scale plants to produce cellulosic biofuels have begun operating. Multiple pathways for the conversion of different biofuel feedstocks are being used. In the next few years, the cost data of these technologies operating at commercial scale, and their relative performance, will become available. Lessons learnt will lower the costs of the industrial processes involved.
  • 939
  • 26 Oct 2022
Topic Review
Nucleophilic Substitution
A nucleophilic substitution is a class of chemical reactions in which an electron-rich chemical species (known as a nucleophile) replaces a functional group within another electron-deficient molecule (known as the electrophile). The molecule that contains the electrophile and the leaving functional group is called the substrate. The most general form of the reaction may be given as the following: The electron pair (:) from the nucleophile (Nuc) attacks the substrate (R-LG) and bonds with it. Simultaneously, the leaving group (LG) departs with an electron pair. The principal product in this case is R-Nuc. The nucleophile may be electrically neutral or negatively charged, whereas the substrate is typically neutral or positively charged. An example of nucleophilic substitution is the hydrolysis of an alkyl bromide, R-Br under basic conditions, where the attacking nucleophile is OH− and the leaving group is Br−. Nucleophilic substitution reactions are common in organic chemistry (especially introductory organic chemistry). Nucleophiles often attack a saturated aliphatic carbon. Less often, they may attack an aromatic or unsaturated carbon.
  • 800
  • 26 Oct 2022
Topic Review
Nanocellulose’s Unique Characteristics as a Chemical Sensor
Composites can be derived from plant-based nanomaterials, among which is nanocellulose which has attracted significant attention as potential replacements for their more conventional petroleum-derived counterparts for use in chemical sensing applications.
  • 776
  • 26 Oct 2022
Topic Review
Supercritical Fluid Extraction as a Green Extraction
Extraction is a technique of isolating components from natural materials using chemical or physical methods. The world has turned to using green extraction as part of its efforts to preserve the environment. Green extraction is based on procedures that require less energy, allow for the use of alternative solvents and sustainable natural resources, and offer a safe and high-quality extract. Supercritical fluid extraction (SFE) procedures are compatible with the principles of green extraction.
  • 915
  • 26 Oct 2022
Topic Review
Biological and Therapeutical Properties of Silica-Based Nanoparticles
Nanoscience and nanotechnology explore the properties and application of particulate systems at the nanometric size. At this scale, materials exhibit properties and characteristics different from their bulk form due to the surface and quantum confinement effects. These effects are related to the increase in the area/volume ratio, which can improve textural properties, such as specific surface area and porosity. Additionally, quantum effects are involved with electronic and optical modifications. When considering their unique properties and characteristics, nanoparticles and nanomaterials have been widely used in water remediation, pesticide detection, and especially in biomedical applications. Despite their excellent properties, the toxicity of nanoparticles (NPs) is a common concern for the scientific community.
  • 473
  • 26 Oct 2022
Topic Review
Production of Mono-, Few-, and Multi-Layer Graphene
Mono-, few-, and multi-layer graphene can be synthesized using various methods, including micromechanical exfoliation, chemical vapour deposition, and chemical methods such as oxidizing graphene into graphene oxide and then reducing it chemically or thermally.
  • 1.8K
  • 26 Oct 2022
Topic Review
Expanding Monomers
Expanding Monomers are monomers which are increasing in volume (expanding) during polymerization. They can be added to monomer formulations to counteract the usual volume shrinking (during polymerization) to manufacture products with higher quality and durability. Volume Shrinkage is in first line for the unmeltable thermosets a problem, since those are of fixed shape after polymerization completed.:2
  • 804
  • 25 Oct 2022
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