七硫化四磷

The little splints of wood which we call matches are made out of deal or pine wood which has been soaked in melted paraffin wax to make it burn more easily. 这种被我们称之为火柴的薄木片由欧洲赤松(松树)制成, 在液体的石蜡

发表于:2018-12-18 / 阅读(77) / 评论(0) 分类 英国学生科学读本

Have you ever had a problem getting a match to light? If so, you might be using the wrong type of match. There are actually two different types of matches: safety matches and strike-anywhere matches. 以前你点燃火柴时有没有点不着的时候呢

发表于:2018-12-18 / 阅读(70) / 评论(0) 分类 2018年NPR美国国家公共电台2月

I couldn't get over this mess. The federal government is confirming what Joan Glickman of Pompano Beach, Florida suspected all along. Tainted drywall from China is giving off a harmful gas that's turning her air-conditioning wiring black, causing it

发表于:2018-12-20 / 阅读(88) / 评论(0) 分类 cnn2009年(十一)月

Mercury Fillings Seem Safer over Time A study in the journal Chemical Research in Toxicology finds that mercury on the surface of dental fillings slowly turns to an inert sulfide compound, which should keep the mercury from harming the nervous system

发表于:2019-01-02 / 阅读(150) / 评论(0) 分类 60秒科学

This is Scientific American's 60-Second Science, I'm Christopher Intagliata. Got a minute? Life on earth requires six basic ingredientscarbon, hydrogen, nitrogen, oxygen, sulfur and phosphorus. Those six elements are the building blocks for DNA and R

发表于:2019-01-08 / 阅读(99) / 评论(0) 分类 Scientific American(十二)月

This is the VOA Special English Agriculture Report. Hogs at an Ohio farm Research shows that waste from pigs that are fed a special kind of corn may help a farmer's crops. And it also may help the environment. Any farmer who raises swine knows that

发表于:2019-01-11 / 阅读(119) / 评论(0) 分类 VOA慢速英语2008年(八)月

From VOA Learning English, this is the Health Lifestyle report. Garlic is one of the most common cooking ingredients around the world. Many dishes in Europe, Africa, Asia and the Americas use this strong-flavored vegetable. Garlic is similar to other

发表于:2019-01-12 / 阅读(130) / 评论(0) 分类 2016年VOA慢速英语(十二)月

By Peter Fedynsky Moscow 18 July 2007 Officials in Ukraine are assessing the damage of a train crash in western Ukraine that sent huge clouds of burning phosphorus billowing into the air. The accident, which took place Monday, is raising health conce

发表于:2019-01-12 / 阅读(106) / 评论(0) 分类 2007年VOA标准英语(七月)

MARY LOUISE KELLY, HOST: Summertime brings algae blooms to many parts of the country - those mats of bright green organisms that can blanket waterways. In places like Florida's Lake Okeechobee, the blooms hurt tourism. They kill fish. They threaten w

发表于:2019-01-17 / 阅读(95) / 评论(0) 分类 2018年NPR美国国家公共电台7月

Black Tongues and Stomach Aches Don: Oh, no, Ya?l, I think I'm having a medical emergency. Quick! Call an ambulance. Ya?l: A medical emergency, Don? Are you sure? You look fine to me! D: But I'm not. This morning, I had a terrible stomach ache. And n

发表于:2019-01-26 / 阅读(78) / 评论(0) 分类 英语听力文摘 English Digest

Sewage stinks. But bacteria can make it smell better. Oh, yeah? That's true. Certain forms of bacteria feasting on sewage give off hydrogen sulfide, a really malodorous chemical, and one of several that give sewage its pleasing smell. In general this

发表于:2019-01-26 / 阅读(81) / 评论(0) 分类 英语听力文摘 English Digest

The commercial potential for the stuffwhich soon became known as phosphorus, from Greek and Latin roots meaning light bearingwas not lost on eager businesspeople, but the difficulties of manufacture made it too costly to exploit. An ounce of phosphor

发表于:2019-01-29 / 阅读(87) / 评论(0) 分类 万物简史

与数字有关的英语词根总结 milli-【千分之一】例:milliampere(毫安)=milli(千)+ampere(安培) centi【百分之一】例:centimeter(厘米)=centi(百分之一)+meter(米) deci【十分之一】例:decibe

发表于:2019-02-06 / 阅读(171) / 评论(0) 分类 英语学习方法

Matches Striking matches, on this Moment of Science. Have you ever had a problem getting a match to light? If so, you might be using the wrong type of match. There are actually two different types of matches: safety matches and strike-anywhere matche

发表于:2019-02-26 / 阅读(90) / 评论(0) 分类 英语听力文摘 English Digest
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