Raman detection of hydrohalite formation: Avoiding accidents on icy roads by deicing where salt will not work

Abstract

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Physical Characterization of Frozen Aqueous Solutions Containing Sodium Chloride and Humic Acid at Environmentally Relevant Temperatures

“…We cannot rule out the possibility that liquid water is present at locations that contain hydrohalite and HA because of the perturbation of the nonzero tail of the Raman O−H stretch peak of hydrohalite 9 that overlaps with the Raman O− H stretch region of liquid water. However, the hydrohalite spectra we acquired in this work look very similar to those we acquired at frozen aqueous NaCl solutions in the absence of HA, 11 and also similar to spectra of hydrohalite acquired after water ice had sublimated (i.e., when no water, either liquid or solid, was present).…”

“…However, the hydrohalite spectra we acquired in this work look very similar to those we acquired at frozen aqueous NaCl solutions in the absence of HA, 11 and also similar to spectra of hydrohalite acquired after water ice had sublimated (i.e., when no water, either liquid or solid, was present). 9 It is therefore likely that liquid water is not spatially co-located with hydrohalite. We also do not expect liquid water to exist in regions of bare ice, as even at higher temperatures we do not detect liquid water at air−ice interfaces.…”

“…Seawaterand, at lower temperatures, sea iceare important environmental reaction media. − Reaction kinetics at air–ice interfaces depend on the physical and chemical properties there. Phase diagrams of some binary aqueous solutions (such as H 2 O–NaCl) predict the solute–solvent volume fractions in frozen systems, − but do not describe the microscopic distribution of the species and hence the degree of spatial heterogeneity within the bulk system and at the air–ice interface. Spatially resolved studies reveal that ionic solutes can be distributed heterogeneously across ice surfaces and throughout the ice bulk. − We recently reported that liquid water in frozen H 2 O–NaCl systems is distributed heterogeneously throughout the ice sample, and that it incompletely covers ice surfaces at most environmentally relevant temperatures and NaCl concentrations …”

Application of a Cryo-FIB-SEM-μRaman Instrument to Probe the Depth of Vitreous Ice in a Frozen Sample

“…As shown in figure 2,b, a difference can be observed, in the low frequency range, between the Raman spectra measured at the two working temperatures. A sharp peak was observed at ~199 cm -1 in the spectrum acquired at 153 K. The Raman band observed at ~199 cm -1 is most likely associated with a translational lattice mode of a crystalline phase that was formed within the aqueous solution after heating [36]. Generally, warming vitreous ice to temperatures above 143 K results in an irreversible transformation of the amorphous structure to Ih [37].…”

Intelligent and efficient? An empirical analysis of human–AI collaboration for truck drivers in retail logistics

“…In addition to these efficiency- and effectiveness-centred approaches, AI is used to enhance the security of roads. For example, salt de-icing trucks have been equipped with AI components to decide whether salt on icy roads will work (Berg, 2018), and AI has been used to automatically detect unsafe trespassing of railroad tracks through railroad video live streams (Zaman et al , 2019). Second, AI has been applied to trucks involved in freight transport systems.…”