The inventor Henry Bessemer discovered that directing a blast of air at melted iron in a furnace would burn out the impurities that made the iron brittle.

发明家亨利·贝塞默发现，在熔炉里对铁水直接吹一吹气，就会烧掉使铁变脆的杂质。

Factories that burn coal still polluted the air with a lot of black smoke.

烧煤的工厂仍然产生大量的黑烟污染空气。

Wind turbines do not burn oil or coal and do not pollute the air.

风力涡轮机不烧石油和煤炭，也不会对空气产生污染。

But if we burn coal in the 21st century using 20th century technologies, our air will be foul and disruptions to our climate will threaten us all.

但是，如果我们在21世纪用20世纪的技术烧煤，我们的空气将被污染，我们的气候会被破坏，这将使所有人受到威胁。

In the air was the smell of burning human flesh; human beings burn surprisingly quickly.

空气中弥漫着人体烧焦的味道，人的躯体的燃烧速度快得惊人。

Nitrogen is removed from the air, enabling the fuel to burn in pure oxygen.

氮气从空气中被去除，使得燃料能够在纯氧中燃烧。

The trouble was that at high altitudes where there is less oxygen, the propeller blades had little air to bite and engines still needed oxygen to burn petrol.

麻烦的是，高海拔的地段，氧气稀薄，螺旋桨叶片没有空气使其扇动，而且发动机燃烧汽油也需要氧气。

Plus, cigars often burn for longer periods of time, which leads to more secondhand smoke in the air.

此外，由于雪茄比起香烟，通常会燃烧更长时间，因此会产生更多的二手烟雾。

Many of them burn wood, waste and dung indoors for heating and cooking. The soot released into the air as a consequence is also a climate-changer because, being dark, it absorbs heat.

很多农民通过燃烧木头、垃圾和粪便来取暖、烧饭，排放到大气中的煤烟因为是黑色而吸热同样会造成气候变化。

Mountain air contains less oxygen than air at lower altitudes, so breathing it causes the heart to beat faster and the body to burn more energy.

高山上的空气含氧量小于比低海拔地区，所以呼吸时心脏会跳动地更快，身体也会消耗更多能量。

Both of these are fuels (they burn in air to form carbon dioxide and water, respectively).

这两种产物都是燃料，燃烧之后产物分别是二氧化碳和水。

If your engine's wheezing and has to work harder bringing in the air it needs to burn fuel efficiently, it doesn't complain to you.

如果你的爱车引擎有杂音而且在燃烧汽油时加入空气更加费劲时，它并不会向你抱怨什么。

The pan must not be crowded. Enough air space must be left between each piece of food or it will steam rather than brown, and its juices will escape and burn in the pan.

不能一下子放太多食物到锅里，必须在食材间留出充足的空间，否则就变成蒸而不是煎了，而且食物里的汤汁也会跑出来，在锅子里蒸发掉。

Air slipping along the fuselage moves slower, so the engines ingest less oxygen and burn less fuel.

机身上流动的空气速度减慢，所以引擎的吸氧量减少从而节省了燃料。

Tasked with improving the nation's air transportation, NASA wants airplanes to burn 40 percent less fuel than a 777 by 2020 and 70 percent less by 2030.

为了提升航空运输，美国国家宇航局希望在2020年前，飞机能比现有“777”号减少40%燃油；并在2030年，减少70%。

The software can work out, for example, the exact rate at which a plane should rise into thinner air (to reduce drag) as fuel burn makes it lighter.

比如，它能够计算出飞机向最薄的云层（以减轻阻力）上升的准确率，以减轻飞机自身重量。

Power plants and houses that burn coal add greatly to air pollution.

燃烧煤炭的发电厂和房屋也大大加重空气污染。

Hydrogen and air mixtures, within the flammable range, can explode and may burn with a pale blue, almost invisible flame.

在可燃范围内的氢和空气的混合物可能爆炸，也可能燃烧，火焰是淡蓝色，几乎看不见。

The harmful air pollution of boiler smoke is introduced and the measure to burn coal fully and reduce the pollution is adopted.

介绍了锅炉烟气对大气污染的危害及采取锅炉节煤措施，使燃料充分燃烧、缓解污染的方法。

In order for fire to burn, air is necessary, hence the necessity of the breath.

为了让火燃烧，空气是必要的，因此呼吸的必要性。

Can burn, vapor and air to form an explosive mixture, the explosion limit of 7%-73% (volume).

能燃烧，蒸气与空气形成爆炸性混合物，爆炸极限7% - 73%(体积)。

Hydrogen is added to the air mixture, causing it to burn easily and powerfully while the oxygen increases the octane value of the fuel.

氢气被添加到混合空气中，可使其既容易又很强力燃烧，而氧气会增加燃油的辛烷值。

A fire requires fuel to burn, air to supply oxygen, and a heat source to bring the fuel up to ignition temperature.

一把火需要燃料来燃烧、空气来提供氧气还有使燃料到底燃烧温度的热量。

Fuels can burn with air.

燃料接触空气能够燃烧。

Meyer says there is evidence that people in chronically distracted jobs are, in early middle age, appearing with the same symptoms of burn-out as air traffic controllers.

Meyer说，有证据表明中年以前，长期在分心状态下工作的人会出现精力耗尽的相同症状，如空中交通管制员。

Butt air is now being polluted by modern transportation, notably gas-powered automobiles, as well as electrical generators that burn fossil fuels and pour polluting chemical waste into the air.

但是，现在的空气污染正受到现代交通运输业的污染，尤其是天然气汽车，以及燃烧矿物燃料的发电机，把污染的化学废物倾倒在空气中。

Deflagration is what happens when you burn a mixture of air and fuel at reasonably low pressure.

爆燃时会发生什么是刻录在合理的低压力的空气和燃料的混合物。

If we burn them, they not only harm people, but (also) pollute the air.

如果烧了这些树叶，不但会损害人体健康而且污染环境。

Automobiles and factories burn gasoline and coal, which send certain chemicals into the air.

汽车和工厂燃烧的汽油和煤炭会释放有害的化学物质。