This is the story of how one man combined LEDs with solar energy technology to bring high-quality, low-cost electric light to poor people around the world.
VOA: standard.2009.12.13
Absorption is just the opposite of emission, so instead of starting at a high energy level and dropping down, when we absorb light we start low and we absorb energy to bring ourselves up to an n final that's higher.
吸收就是发射的逆过程,与从一个高能量到低能量不同,当吸收光时,我们从低能量开始,吸收能量到一个更高的能量。
He did it to bring more light, he did it to bring more air, he did it to free the flow for capital, money; that's why the department stores are on the boulevards.
他这么做是为了多点光,多点新鲜空气,他为了使资产的流动更为自由,这就是为什么百货商店都建在大道旁边
He's also decided to give up leadership in Light up the World Foundation to start a company in India that will develop a more energy-efficient and cheaper lighting system that he hopes will bring even more light to the world's poor.
VOA: standard.2009.12.13
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