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The Uniform Invoice or Unified Invoice (統一發票 pinyin: Tǒngyī fāpiào), is a type of receipt in Taiwan that is issued by merchants for selling products and services, kept by both seller and consumer, with a 8-digit number for each one, for taxation purposes of the
3LR12 (4.5-volt), D, C, AA, AAA, AAAA (1.5-volt), A23 (12-volt), PP3 (9-volt), CR2032 (3-volt), and LR44 (1.5-volt) batteries. This is a list of the sizes, shapes, and general characteristics of some common primary and secondary battery types in household, automotive and light industrial use. The complete nomenclature for a battery specifies ...
- Production
- Uses
- Chemical Reactions
- Toxicity
- Environmental Effects
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Industrial routes
Ethylene glycol is produced from ethylene (ethene), via the intermediate ethylene oxide. Ethylene oxide reacts with water to produce ethylene glycol according to the chemical equation: C2H4O + H2O → HO−CH2CH2−OH This reaction can be catalyzed by either acids or bases, or can occur at neutral pH under elevated temperatures. The highest yields of ethylene glycol occur at acidic or neutral pH with a large excess of water. Under these conditions, ethylene glycol yields of 90% can be achieved. The...
Biological routes
The caterpillar of the Greater wax moth, Galleria mellonella, has gut bacteria with the ability to degrade polyethylene(PE) into ethylene glycol.
Historical routes
According to most sources, French chemist Charles-Adolphe Wurtz (1817–1884) first prepared ethylene glycol in 1856. He first treated "ethylene iodide" (C2H4I2) with silver acetate and then hydrolyzed the resultant "ethylene diacetate" with potassium hydroxide. Wurtz named his new compound "glycol" because it shared qualities with both ethyl alcohol (with one hydroxyl group) and glycerin (with three hydroxyl groups). In 1859, Wurtz prepared ethylene glycol via the hydration of ethylene oxide....
Coolant and heat-transfer agent
The major use of ethylene glycol is as an antifreeze agent in the coolant in for example, automobiles and air-conditioning systems that either place the chiller or air handlers outside or must cool below the freezing temperature of water. In geothermal heating/cooling systems, ethylene glycol is the fluid that transports heat through the use of a geothermal heat pump. The ethylene glycol either gains energy from the source (lake, ocean, water well) or dissipates heat to the sink, depending on...
Anti-freeze
Pure ethylene glycol freezes at about −12 °C (10.4 °F) but, when mixed with water, the mixture freezes at a lower temperature. For example, a mixture of 60% ethylene glycol and 40% water freezes at −45 °C (−49 °F). Diethylene glycol behaves similarly. The freezing point depression of some mixtures can be explained as a colligative property of solutions but, in highly concentrated mixtures such as the example, deviations from ideal solution behavior are expected due to the influence of intermo...
Precursor to polymers
In the plastic industry, ethylene glycol is an important precursor to polyester fibers and resins. Polyethylene terephthalate, used to make plastic bottles for soft drinks, is prepared from ethylene glycol.
Ethylene glycol is used as a protecting group for carbonyl groups in organic synthesis. Treating a ketone or aldehyde with ethylene glycol in the presence of an acid catalyst (e.g., p-toluenesulfonic acid; BF3·Et2O) gives the corresponding a 1,3-dioxolane, which is resistant to bases and other nucleophiles. The 1,3-dioxolane protecting group can th...
Ethylene glycol has relatively high mammalian toxicity when ingested, roughly on par with methanol, with an oral LDLo = 786 mg/kg for humans. The major danger is due to its sweet taste, which can attract children and animals. Upon ingestion, ethylene glycol is oxidized to glycolic acid, which is, in turn, oxidized to oxalic acid, which is toxic. It...
Ethylene glycol is a high-production-volume chemical. It breaks down in air in about 10 days and in water or soil in a few weeks. It enters the environment through the dispersal of ethylene glycol-containing products, especially at airports, where it is used in de-icing agents for runways and airplanes. While prolonged low doses of ethylene glycol ...
World War I or the First World War (28 July 1914 – 11 November 1918) was a global conflict between two coalitions: the Allies and the Central Powers.Fighting took place throughout Europe, the Middle East, Africa, the Pacific, and parts of Asia.One of the deadliest wars in history, it resulted in an estimated 9 million soldiers dead and 23 million wounded, plus up to 8 million civilian deaths ...
One half is a rational number that lies midway between nil and unity (which are the elementary additive and multiplicative identities) as the quotient of the first two non-zero integers, . It has two different decimal representations in base ten, the familiar and the recurring , with a similar pair of expansions in any even base; while in odd ...
Two and a Half Men is an American television sitcom created by Chuck Lorre and Lee Aronsohn that originally aired on CBS from September 22, 2003, to February 19, 2015, with a total of twelve seasons consisting of 262 episodes.Originally starring Charlie Sheen in the lead role alongside Jon Cryer and Angus T. Jones, the series was about a hedonistic jingle writer, Charlie Harper, his uptight ...
India is a federal constitutional republic governed under a parliamentary system consisting of 28 states and 8 union territories. [1] All states, as well as the union territories of Jammu and Kashmir, Puducherry and the National Capital Territory of Delhi, have elected legislatures and governments, both patterned on the Westminster model.
