科学素养与生活应用·英语30篇（5）

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How LED Streetlights Save Energy and Reduce Light Pollution

LED路灯如何节能并减少光污染

LED streetlights use semiconductors to convert electricity directly into visible light, achieving up to 50% greater efficiency than high-pressure sodium lamps.
Directional optics focus light downward onto roads and sidewalks, minimizing upward spill that brightens night skies and disrupts wildlife behavior.
Dimmable drivers allow cities to lower brightness by 30% after midnight, cutting energy use without sacrificing safety in low-traffic hours.
Warmer-color LEDs (around 3000K) emit less blue light than cooler versions, reducing melatonin suppression in humans and disorientation in migrating birds.
Smart controllers link lights into networks, enabling remote monitoring of failures and predictive maintenance before outages occur.
Life spans exceed 100,000 hours—nearly ten times longer than older bulbs—reducing replacement frequency and associated labor and waste.
Shielded fixtures certified by the International Dark-Sky Association meet strict cutoff angles to prevent glare and skyglow.
Pilot programs in Tucson and Flagstaff show measurable improvements in star visibility and reduced energy bills after full LED retrofits.

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③ 学 · 重点表达

LED streetlights use semiconductors to convert electricity directly into visible light, achieving up to 50% greater efficiency than high-pressure sodium lamps. LED路灯利用半导体直接将电能转化为可见光，效率比高压钠灯高出约50%。
Directional optics focus light downward onto roads and sidewalks, minimizing upward spill that brightens night skies and disrupts wildlife behavior. 定向光学设计将光线集中投射到道路和人行道上，最大限度减少向天空散射的光，从而缓解夜空变亮及对野生动物行为的干扰。
Dimmable drivers allow cities to lower brightness by 30% after midnight, cutting energy use without sacrificing safety in low-traffic hours. 可调光驱动器使城市可在午夜后将亮度降低30%，在车流稀少时段节省能耗而不影响安全。

④ 懂 · 选一选

这篇中文题目最接近哪一句？ LED路灯如何节能并减少光污染一次学校运动会的通知一份超市购物清单

课文第一句的意思更接近？ LED路灯利用半导体直接将电能转化为可见光，效率比高压钠灯高出约50%。今天学校放假了。请把窗户打开。

这一课主要在讲什么？（看英文标题） How LED Streetlights Save Energy and Reduce Light Pollution How to cook noodles A maths worksheet

⑤ 今天会说这一句

LED streetlights use semiconductors to convert electricity directly into visible light, achieving up to 50% greater efficiency than high-pressure sodium lamps.

⑥ 跟读并录音

LED streetlights use semiconductors to convert electricity directly into visible light, achieving up to 50% greater efficiency than high-pressure sodium lamps.

第一版：录下来、回听、再听标准音。系统打分以后再加。

⑦ 说 · 自己来一句

用今天的表达，自己说一句。

例子：LED streetlights use semiconductors to convert electricity directly into visible light, achieving up to 50% greater efficiency than high-pressure sodium lamps.