Objective: to understand the pollution of the Yellow River in HuiNong of NingXia Autonomous Prefecture and in natural water source and running water quality.

前言：目的：掌握黄河水源宁夏惠农段污染现状和目前自来水水质现状。

youdao

An artificial leaf would use a reaction that forms part of the natural process of photosynthesis to turn sunlight and water into a clean fuel source.

“人造叶”将利用构成光合作用中部分自然过程的反应作用，将阳光和水变成一种清洁燃料的来源。

youdao

Cooperand colleagues demonstrated in previous studies that dry water is also usefulfor storing methane, a component of natural gas, and may help expand its use asa future energy source.

在此前的研究中，库珀等人同样发现干水可用于储存天然气成分之一的甲烷，进而帮助扩大甲烷作为未来能源的应用前景。

youdao

The site, which contains a natural spring, is the nearest source of fresh water to Stonehenge.

BBC: Stonehenge occupied 5,000 years earlier than thought

Despite their importance to our nation as a source for economic and natural resources, we know very little about deep-water habitats in the Gulf of Mexico.

WHITEHOUSE: Watch Live: Be a Virtual Ocean Explorer