Carbon dioxide makes up less than one percent of the Earth’s atmosphere. But the gas is very important to life on Earth. Scientists are finding that processes involving carbon dioxide affect our climate in ways that are difficult to understand. Last month, a committee of the National Academy...
A. oxygen (氧气) B. carbon dioxide (二氧化碳) C. nitrogen (氮气) D. hydrogen (氢气) 相关知识点: 试题来源: 解析 C 正确答案:C 解析:大气的主要成分是氮气(nitrogen)哦,大概占大气总成分的78%左右, 而氧气(oxygen)只占20%左右,剩余的2%由二氧化碳(carbon dioxide)等其他气体组成。反馈...
根据第一段中的“We all think plants were expected to get larger with increased carbon dioxide in the atmosphere, but changes in temperature, humidity(湿度)and nutrient availability seem to have trumped the benefits of increased carbon dioxide”可知科学家原来以为二氧化碳的增加会导致物种变大,但是气候...
The burning of fossil fuels and the clearing of forests have increased atmospheric carbon dioxide by about 15 percent in the last hundred years, and we continue to add carbon dioxide to the atmosphere. 问题 句子分析(俗称“长难句分析”)是训练提高基础阅读能力的有效手段。我们通过对托福(TOEFL)、...
" The thin atmosphere on Mars is 96 percent carbon dioxide and much more(7) changeable( change) than on Earth and the temperature can vary by 100 degrees,"Hoffman said."One aim is to show we can run Moxie in all seasons." The device,Moxie,uses some special pumps,(8...
awhat factors led to the steadily rising concenteation of carbon dioxide in the atmosphere 正在翻译,请等待...[translate] aA development coalition between politics and administration with an increase in overall competence and based on a change in the political role offers at least the chance of ...
Ironically, this gain in water storage is only made possible by global warming, which has increased the concentration of carbon dioxide in the atmosphere by about 25 percent since 1950. In the experiments, the tobacco plants could take in enough CO2 – despite the stomata's shortened work day...
Pinatubo in 1991, actually lead to short-term global cooling, not warming, as sulfur dioxide (SO2), ash and other particles in the air and stratosphere(平流层) reflect some solar energy instead of letting it into Earth's atmosphere. SO2, which converts to sulfuric acid aero...
根据文章第二段“Growing and harvesting beans requires energy which releases a lot of carbon dioxide(CO2)into the atmosphere(种植和收获豆类需要能量,而能量会向大气中释放大量二氧化碳)”可知,此处说明咖啡产业会产生碳排放。故选C项。 (2)题详解: 细节理解题。根据文章第二段“A not-so-fun fact is ...
The proportion of embryos hatching and cell counts were significantly greater ( P > 0.01) when cultured in the presence of 10% CO 2 . These data indicate that a 10% CO 2 atmosphere exerts a beneficial effect on the development of zygotes into expanding and hatching rabbit blastocysts in ...