時(shí)差N小時(shí):液態(tài)氣的燃點(diǎn)

People who work with chemicals make sure theyknow the flash point of each substance in their labs.A flash point is the temperature at which the fumesfrom a liquid can be ignited with a spark.

與化學(xué)藥品打交道的人，總會(huì)確保自己知道實(shí)驗(yàn)室中每一種物質(zhì)的燃點(diǎn)。燃點(diǎn)是液態(tài)氣體能被火花點(diǎn)燃的溫度。

But people who have never taken a chemistry courseneed to be concerned with flash points as well. Forexample, the gasoline you put into your car has aflash point of minus forty-five degrees Fahrenheit.

但未曾上過化學(xué)課的人同樣需要關(guān)注物質(zhì)的燃點(diǎn)。例如，你加入車?yán)锏钠腿键c(diǎn)是華氏零下45度。

So, unless you live in a climate where the temperature stays below minus forty-five degrees,the fumes from gasoline can ignite from a nearby spark. And that’s why most gas stationshave warning signs posted about not smoking while you fill up your tank.

所以，除非你生活在溫度維持在華氏零下45度以下的環(huán)境里，汽油逸出的煙霧才不會(huì)被附近的明火點(diǎn)燃。這也是為什么大多數(shù)加油站都張貼警告標(biāo)志，告戒人們不要在給車加油時(shí)吸煙。

Olive oil has a flash point of 437 degrees Fahrenheit. That means if you could heat olive oil to437 degrees, it would give off a vapor that could ignite if a lit match passed through it. Codliver oil has a flash point of 412 degrees Fahrenheit and formaldehyde has a flash point of 122degrees.

橄欖油的燃點(diǎn)是華氏437度。這意味著如果你把橄欖油加熱至437度，它散發(fā)出的蒸氣完全可以被一根劃過去的、燃著的火柴點(diǎn)燃。魚肝油的燃點(diǎn)是華氏412度，而甲醛的燃點(diǎn)是122度。

Most flash points are inconsequential to the lay person because they occur at such hightemperatures. But some, like kerosene, with a flash point of 100 degrees Fahrenheit, can because for concern on a hot day. If you keep an old-fashioned kerosene lamp on your fireplacemantel, you probably shouldn’t light it on a hot summer day, or you might ignite more thanjust the wick of the lamp.

大多數(shù)物質(zhì)的燃點(diǎn)對于業(yè)外人士來說不重要，因?yàn)樗鼈冎辉诟邷貤l件下出現(xiàn)。但是，一些像煤油一樣，燃點(diǎn)為華氏100度的物質(zhì)，在炎熱的日子里著實(shí)令人擔(dān)憂。如果你的壁爐架上有一盞老式煤油燈，你最好不要在炎熱的夏天點(diǎn)燃它，因?yàn)槟泓c(diǎn)燃的可能不僅僅是煤油燈的燈芯。