气候变化领域集成服务门户(CCPortal): Direct visualization of solute locations in laboratory ice samples

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DOI	10.5194/tc-10-2057-2016
	Direct visualization of solute locations in laboratory ice samples
	Hullar T.; Anastasio C.
发表日期	2016
ISSN	19940416
卷号	10 期号:5
英文摘要	Many important chemical reactions occur in polar snow, where solutes may be present in several reservoirs, including at the air-ice interface and in liquid-like regions within the ice matrix. Some recent laboratory studies suggest chemical reaction rates may differ in these two reservoirs. While investigations have examined where solutes are found in natural snow and ice, few studies have examined either solute locations in laboratory samples or the possible factors controlling solute segregation. To address this, we used micro-computed tomography (microCT) to examine solute locations in ice samples prepared from either aqueous cesium chloride (CsCl) or rose bengal solutions that were frozen using several different methods. Samples frozen in a laboratory freezer had the largest liquid-like inclusions and air bubbles, while samples frozen in a custom freeze chamber had somewhat smaller air bubbles and inclusions; in contrast, samples frozen in liquid nitrogen showed much smaller concentrated inclusions and air bubbles, only slightly larger than the resolution limit of our images (∼ 2 μm). Freezing solutions in plastic vs. glass vials had significant impacts on the sample structure, perhaps because the poor heat conductivity of plastic vials changes how heat is removed from the sample as it cools. Similarly, the choice of solute had a significant impact on sample structure, with rose bengal solutions yielding smaller inclusions and air bubbles compared to CsCl solutions frozen using the same method. Additional experiments using higher-resolution imaging of an ice sample show that CsCl moves in a thermal gradient, supporting the idea that the solutes in ice are present in mobile liquid-like regions. Our work shows that the structure of laboratory ice samples, including the location of solutes, is sensitive to the freezing method, sample container, and solute characteristics, requiring careful experimental design and interpretation of results. © Author(s) 2016.
学科领域	air bubble; air-ice interaction; chemical reaction; experimental design; ice; laboratory method; solute; temperature effect; visualization
语种	英语
scopus关键词	air bubble; air-ice interaction; chemical reaction; experimental design; ice; laboratory method; solute; temperature effect; visualization
来源期刊	Cryosphere
文献类型	期刊论文
条目标识符	http://gcip.llas.ac.cn/handle/2XKMVOVA/119586
作者单位	Department of Land, Air, and Water Resources, University of California, Davis, United States
推荐引用方式 GB/T 7714	Hullar T.,Anastasio C.. Direct visualization of solute locations in laboratory ice samples[J],2016,10(5).
APA	Hullar T.,&Anastasio C..(2016).Direct visualization of solute locations in laboratory ice samples.Cryosphere,10(5).
MLA	Hullar T.,et al."Direct visualization of solute locations in laboratory ice samples".Cryosphere 10.5(2016).