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Alibaba Group Holding Limited, branded as Alibaba, is a Chinese multinational technology company specializing in e-commerce, retail, Internet, and technology. Founded on 28 June 1999 [1] in Hangzhou, Zhejiang, the company provides consumer-to-consumer (C2C), business-to-consumer (B2C), and business-to-business (B2B) sales services via Chinese ...
In a DNA double helix, each type of nucleobase on one strand bonds with just one type of nucleobase on the other strand. This is called complementary base pairing.Purines form hydrogen bonds to pyrimidines, with adenine bonding only to thymine in two hydrogen bonds, and cytosine bonding only to guanine in three hydrogen bonds. . This arrangement of two nucleotides binding together across the ...
Warren Edward Buffett (/ˈbʌfɪt/ BUF-it; born August 30, 1930)[2] is an American businessman, investor, and philanthropist who currently serves as the co-founder, chairman and CEO of Berkshire Hathaway. As a result of his investment success, Buffett is one of the best-known investors in the world. As of April 2024, he had a net worth of $139 ...
Space Exploration Technologies Corporation, commonly referred to as SpaceX, is an American spacecraft manufacturer, launch service provider and satellite communications company headquartered in Hawthorne, California.The company was founded in 2002 by Elon Musk with the goal of reducing space transportation costs and ultimately developing a sustainable colony on Mars.
- Structure
- Production
- Applications
- Metabolism
- Historical Cases of Contamination with Diethylene Glycol
- Etymology
- See Also
- External Links
Although achiral, glycerol is prochiral with respect to reactions of one of the two primary alcohols. Thus, in substituted derivatives, the stereospecific numbering labels the molecule with a sn- prefix before the stem name of the molecule.
Glycerol is generally obtained from plant and animal sources where it occurs in triglycerides, esters of glycerol with long-chain carboxylic acids. The hydrolysis, saponification, or transesterificationof these triglycerides produces glycerol as well as the fatty acid derivative: Triglycerides can be saponified with sodium hydroxide to give glycero...
Food industry
In food and beverages, glycerol serves as a humectant, solvent, and sweetener, and may help preserve foods. It is also used as filler in commercially prepared low-fat foods (e.g., cookies), and as a thickening agent in liqueurs. Glycerol and water are used to preserve certain types of plant leaves. As a sugar substitute, it has approximately 27 kilocalories per teaspoon (sugar has 20) and is 60% as sweet as sucrose. It does not feed the bacteria that form a dental plaque and cause dental cavi...
Medical, pharmaceutical and personal care applications
Glycerol is used in medical, pharmaceutical and personal care preparations, often as a means of improving smoothness, providing lubrication, and as a humectant. Ichthyosis and xerosis have been relieved by the topical use of glycerin. It is found in allergen immunotherapies, cough syrups, elixirs and expectorants, toothpaste, mouthwashes, skin care products, shaving cream, hair care products, soaps, and water-based personal lubricants. In solid dosage forms like tablets, glycerol is used as a...
Botanical extracts
When utilized in "tincture" method extractions, specifically as a 10% solution, glycerol prevents tannins from precipitating in ethanol extracts of plants (tinctures). It is also used as an "alcohol-free" alternative to ethanol as a solvent in preparing herbal extractions. It is less extractive when utilized in a standard tincture methodology. Alcohol-based tinctures can also have the alcohol removed and replaced with glycerol for its preserving properties. Such products are not "alcohol-free...
Glycerol is a precursor for synthesis of triacylglycerols and of phospholipids in the liver and adipose tissue. When the body uses stored fat as a source of energy, glycerol and fatty acidsare released into the bloodstream. Glycerol is mainly metabolized in the liver. Glycerol injections can be used as a simple test for liver damage, as its rate of...
On 4 May 2007, the FDA advised all U.S. makers of medicines to test all batches of glycerol for diethylene glycol contamination. This followed an occurrence of hundreds of fatal poisonings in Panama resulting from a falsified import customs declaration by Panamanian import/export firm Aduanas Javier de Gracia Express, S. A. The cheaper diethylene g...
The origin of the gly- and glu- prefixes for glycols and sugars is from Ancient Greek γλυκύς glukus which means sweet. Name glycérine was coined ca. 1811 by Michel Eugène Chevreul to denote what was previously called "sweet principle of fat" by its discoverer Carl Wilhelm Scheele. It was borrowed into English ca. 1838 and in the 20th c. displaced b...
Mass spectrum of glycerol Archived 13 February 2022 at the Wayback MachineEtymology The Modern English word Earth developed, via Middle English, from an Old English noun most often spelled eorðe. It has cognates in every Germanic language, and their ancestral root has been reconstructed as *erþō.In its earliest attestation, the word eorðe was used to translate the many senses of Latin terra and Greek γῆ gē: the ground, its soil, dry land, the human world ...
High-performance liquid chromatography ( HPLC ), formerly referred to as high-pressure liquid chromatography, is a technique in analytical chemistry used to separate, identify, and quantify specific components in mixtures.
