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我们知道在正常条件下,相同体积的空气要比液态物质和固态物质轻,这是因为空气的密度比液态和固态物质小.那么有没有比空气还轻的固体物质呢?答案是肯定的.目前,科学家已制造出一些比空气还轻的固体材料,其中我国科学家、浙江大学高超教授的研究小组于2013年制造出一种超轻物质,取名“碳海绵”.这是目前世界上最轻的一种固体材料.碳海绵是一种超轻的气凝胶,是以二维纳米材料石墨烯为壁、一维纳米材料碳纳米管为骨架,协同组装成的全碳气凝胶,也就是说它仅由碳元素组成.我们知道,在0℃、1标准大气压下,空气的密度为1.29 mg/cm~3,氢气的密度为0.0899 mg/cm~3,氦气的密度为0.1786 mg/cm~3,而碳海绵的密度为0.16 mg/cm~3,约是空气密度的1/7,约是同体积氢气重量的2倍.碳海绵的孔隙率高达99.9%,充斥着气态分散介质,因此才拥有如此小的密度.它可以“踩”在狗尾巴草上.纤细的
We know that under the normal conditions, the same volume of air is lighter than liquid and solid matter, because air is denser than liquids and solids, so is there any solid matter lighter than air? The answer is in the affirmative. At present, scientists have created some solid materials that are lighter than air, of which the research team of our country’s scientist and professor Gao Jing of Zhejiang University created an ultra-light substance named “carbon sponge” in 2013. This is the current world On the lightest solid material.Carbon sponge is an ultra-light airgel, is a two-dimensional nano-materials graphene wall, one-dimensional nano-materials carbon nanotubes as the skeleton, co-assembled into a full carbon airgel Glue, that is to say it consists of carbon only, and we know that at 0 ° C and 1 standard atmospheric pressure, the air density is 1.29 mg / cm 3 and the hydrogen density is 0.0899 mg / cm 3. The density of helium Is 0.1786 mg / cm ~ 3, while the carbon sponge has a density of 0.16 mg / cm ~ 3, which is about 1/7 of the air density and about twice as much as the hydrogen with the same volume.The carbon sponge has a porosity of 99.9% With a gaseous dispersion medium, it has such a small density. It can “step on ” in the dog tail grass Slender