The simplest and most common way is to coat a blue LED with a yellow phosphor.

最简单也最普通就是在蓝色LED上罩一层黄色的磷。

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Bed planting and water management in the Yellow River: Serious water and soil erosion in the Yellow River has led to frequent basin-wide drought and floods.

黄河流域的垄播和水管理：黄河流域严重的水土流失导致整个流域经常发生水旱灾害。

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This led to our player kicking the ball away in disgust and correctly being given a yellow card.

这个不公正的判罚导致了我们的队员情绪失控，把球踢远并且得到黄牌警告。

youdao

Brown was perhaps fortunate to escape with just a yellow card for a stud-led challenge on Scobbie, while Kevin McBride followed him into the book for a similar challenge seconds later.

BBC: Celtic 4-0 Falkirk

However, Vaughton infringed at the resulting ruck, receiving a yellow card for his troubles, and Lamb ensured the Ospreys only led 12-9 at the interval.

BBC: Gloucester 26-18 Ospreys

In case you don't have your smartphone app handy, the taps are equipped with LED lights to show the water's filter status as well -- blue means clean, yellow means not so much and red means you should probably get a new filter, pronto.

ENGADGET