This process accounts for 60 to 90 percent of the present loss of hydrogen from Earth and most of the hydrogen loss from Venus.

这样的过程占当今地球氢气损失总量的60 ~ 90%，也是金星氢气损失的主要过程。

youdao

Still, hydrogen is the lightest of all elements, so it only accounts for roughly 72 percent of the sun's mass, while helium makes up about 26 percent.

氢也是所有元素中最轻的，所以它大约只占太阳总质量的72%，氦大约占26%。

youdao

The resulting stream of charged particles, called the polar wind (not to be confused with the planetary wind), accounts for 10 to 15 percent of Earth's hydrogen loss and almost its entire helium leak.

由此形成的带电粒子流，就叫做“极地风”(polar wind)，可占地球氢元素泄漏过程的10 ~ 15%，而几乎所有的氦气就是以这种方式脱离地球的。

youdao

It doesn't go all the way to absolutely 100 percent ammoniazero hydrogen zero nitrogen if they were mixed together with the right ratios.

即使按适当比例混合,也不会出现全部氨气,没有氢气和氮气的情况。

麻省理工公开课 - 热力学与动力学课程节选

Pipelines that move hydrogen are said to be 30 percent more expensive than those that carry natural gas.

FORBES: Hydrogen-Powered Vehicles Could Emerge From Traffic

Zhang lead a Virginia Tech team that developed a way to produce large quantities of hydrogen from xylose, an abundant simple sugar that makes up 30 percent of the cell walls of plants.

FORBES: Could Hydrogen Breakthrough Revive The Fuel-Cell Car?

About 15 percent of the new cars sold in California by 2025 must run on electricity, hydrogen fuel or other alternative fuels that produce near zero or no emissions, according to new rules adopted unanimously by state regulators on Friday.

FORBES: California Sets New Rules To Boost Zero-Emission Car Sales