Experimental Study on Formation Process of Ice Particles in Stratospheric Clouds

平流层云中冰粒形成过程的实验研究

基本信息

批准号：
06452086
负责人：
ISHIZAKA Yutaka
金额：
$ 0.83万
依托单位：
Nagoya University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (B)
财政年份：
1994
资助国家：
日本
起止时间：
1994 至 1995
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-06452086/
关键词：
Stratospheric clouds Freezing of acid droplets NAT particles Sulfuric acid droplets Freezing nuclei Ozone depletion Nitric acid 凍結核成層圏氷晶の凍結核酸性水滴の凍結温度成層圏雲粒子

项目摘要

Freezing points of acid droplets were measured in a cryostat under the stratospheric condition and chemical composition of ice particles formed in a cryostat was determined with an electron microscope using thin-film chemical methods. Acid droplets were suspended on the tungsten wires in the sample holder. Size range of the acid droplets was from 10 to 50 mum in diameter. Sulfuric acid, nitric acid, hydrochloric acid and methanesulfonic acid solutions were used to make acid droplets. Droplets were observed with a CCD camera through the microscope. Freezing temperature of droplets was determined by detecting ice embryos in the droplet. It was found from the experiment that freezing point of sulfuric acid droplets decreased linearly with increasing acid concentration. Freezing point of sulfuric acid droplets with acid concentration of 70%wt was about -80ﾟC.Freezing point of nitric acid droplets did not depend strongly on acid concertration, and it was lower than that of sulfuric acid droplets above 35%wt of acid concentration. Hydrochloric acid droplets froze at lower temperatures than freezing points of sulfuric acid and nitric acid droplets. On the other hand, melting points of ice particles were also measured by increasing temperatures of ice particles after acid droplets froze. Further, some of particles before and after freezing of sulfuric acid particles under the supply of nitric acid and water vapor were sampled on an electron microscope mesh covered with barium chloride and nitron films. NO3- ion was not detected in acid droplets, but it was detected in ice particles. The result indicates that nitric acid vapor can be absorbed in ice particles during their growth after acid droplets froze.The results of this laboratory experiments strongly suggests that ice and NAT particles can be formed by freezing of sulfuric acid particles in the stratosphere.

在平流层条件下，在低温恒温器中测量了酸液滴的冰点，使用薄膜化学方法用电子显微镜确定在低温恒温器中形成的冰颗粒的化学成分。将酸液滴悬挂在样品支架中的钨电线上。酸液滴的尺寸范围为10至50妈妈的直径。硫酸，硝酸，盐酸和甲磺酸溶液用于制造酸液滴。通过显微镜使用CCD摄像头观察液滴。通过检测液滴中的冰胚胎来确定液滴的冻结温度。从实验中发现，硫酸液滴的冰点随着酸浓度的增加线性降低。酸浓度为70％wt的硫酸液滴的冰点约为-80 c。硝酸液滴的冻结点不依赖于酸关注，并且低于硫酸液滴的酸性液滴高于35％wt的酸浓度。与硫酸和硝酸液滴的冰点相比，在较低温度下冷冻的盐酸液滴在较低的温度下冷冻。另一方面，还通过酸液滴冷冻后冰颗粒的温度升高来测量冰颗粒的熔点。此外，将硫酸颗粒在硝酸和水蒸气供应下冷冻之前和之后的某些颗粒在覆盖有氯化钡和硝酸薄膜的电子显微镜网上采样。在酸液滴中未检测到No3-ion，但在冰颗粒中被检测到。该实验室实验的结果强烈表明，可以通过在平流层中的硫酸颗粒冷冻来形成冰和NAT颗粒。