While fuel cell or electric vehicles emit no carbon dioxide themselves, CO2 is produced when hydrogen or electricity is produced from fossil fuels.
虽然燃料电池和电动汽车本身不会释放二氧化碳，但使用化石燃料生产氢气或电能依旧会产生二氧化碳。
3
"The same taste cell has all the machinery to turn carbon dioxide into protons and then detect the protons as sour taste stimuli," said Alexander Bachmanov, who was not involved in the study.