Comment on “The nucleation behavior of supercooled water vapor in helium” [J. Chem. Phys. 117, 5647 (2002)]

2004 ◽  
Vol 120 (13) ◽  
pp. 6314-6314 ◽  
Author(s):  
D. G. Labetski ◽  
V. Holten ◽  
M. E. H. van Dongen
Keyword(s):  
Water Vapor ◽  
Supercooled Water ◽  
Chem Phys ◽  
Nucleation Behavior

scholarly journals The nucleation behavior of supercooled water vapor in helium

2002 ◽  
Vol 117 (12) ◽  
pp. 5647-5653 ◽  
Author(s):  
P. Peeters ◽  
J. J. H. Gielis ◽  
M. E. H. van Dongen
Keyword(s):  
Water Vapor ◽  
Supercooled Water ◽  
Nucleation Behavior

scholarly journals Volume analysis of supercooled water under high pressure

MRS Advances ◽  
2018 ◽  
Vol 3 (41) ◽  
pp. 2467-2478
Author(s):  
Solomon F. Duki ◽  
Mesfin Tsige
Keyword(s):  
High Pressure ◽  
Water Sample ◽  
High Pressures ◽  
Supercooled Water ◽  
Supercooled Liquid ◽  
Chem Phys ◽  
Bulk Water ◽  
Isothermal Compression ◽  
Emulsified Water ◽  
Dynamics Simulations

ABSTRACTMotivated by an experimental finding on the density of supercooled water at high pressure [O. Mishima, J. Chem. Phys. 133, 144503 (2010)] we performed atomistic molecular dynamics simulations study of bulk water in the isothermal-isobaric ensemble. Cooling and heating cycles at different isobars and isothermal compression at different temperatures are performed on the water sample with pressures that range from 0 to 1.0 GPa. The cooling simulations are done at temperatures that range from 40 K to 380 K using two different cooling rates, 10 K/ns and 10 K/5 ns. For the heating simulations we used the slowest heating rate (10 K/5 ns) by applying the same range of isobars. Our analysis of the variation of the volume of the bulk water sample with temperature at different pressures from both isobaric cooling/heating and isothermal compression cycles indicates a concave-downward curvature at high pressures that is consistent with the experiment for emulsified water. In particular, a strong concave down curvature is observed between the temperatures 180 K and 220 K. Below the glass transition temperature, which is around 180 K at 1GPa, the volume turns to concave upward curvature. No crystallization of the supercooled liquid state was observed below 180 K even after running the system for an additional microsecond.

Electrical Supercooling Mitigation in Erythritol

2010 ◽  
Author(s):  
Nicholas R. Jankowski ◽  
F. Patrick McCluskey
Keyword(s):  
Electric Current ◽  
Crystallization Behavior ◽  
Supercooled Water ◽  
Heat Of Fusion ◽  
Recrystallization Temperature ◽  
Nucleation Behavior ◽  
Direct Electric Current ◽  
Surface Control ◽  
Before And After ◽  
High Latent Heat

This report describes an experimental investigation into the effect of electric current in reducing the supercooling of erythritol. Previous studies have identified erythritol as a prime material candidate for moderate temperature thermal energy storage (TES) systems due to its high latent heat of fusion and melting temperature (118°C), but it has also shown excessive supercooling, sometimes exceeding 65°C [1]. Various methods for controlling or reducing supercooling are reviewed, including work by Shichiri and Hozumi showing that a small electric current passed through supercooled water is highly effective in initiating nucleation [2,3]. In the present study, the authors demonstrate a similar effect with erythritol by subjecting a sample to repeated thermal cycles with and without the application of a direct electric current. The control cases without electric current showed a highly variable recrystallization temperature ranging from 67°C to 109°C (or supercooling magnitudes from 9 to 51°C). Passing a direct current through the sample using silver wire electrodes significantly shifted the material’s nucleation behavior. The local nucleation temperature only varied from 108°C to 112°C (or 6–10°C of supercooling), and nucleation always occurred on the positive electrode surface. Control cases both before and after the electrical trials indicated no noticeable change in sample crystallization behavior.

Laser concept of the mobile ATMONSYS-lidar and its application during CHEESEHEAD

2020 ◽  
Author(s):  
Hannes Vogelmann ◽  
Johannes Speidel ◽  
Matthias Perfahl
Keyword(s):  
Water Vapor ◽  
Near Infrared ◽  
Laser Emission ◽  
Three Dimensional ◽  
Chem Phys ◽  
Spectral Lines ◽  
Spatiotemporal Variability ◽  
Laser Medium ◽  
Laser Resonator ◽  
Radiative Balance

<p>Water vapor is the most important greenhouse gas and dominates weather patterns, the atmospheric energy budget and radiative balance. For analysing<br />dynamic processes of planetary boundary layer we developed the ATMONSYS lidar for measuring water vapor, aerosols and temperature. In summer 2019 the application of the ATMONSYS lidar was part of the CHEESEHEAD campaign in Northern Wisconsin (USA). Former investigations showed the very high spatio-temporal short term variability of tropospheric water vapor in a three dimensional study [1]. From a technical point of view this also depicted the general requirement of short integration times while recording water-vapor profiles with lidar. For this purpose,  the differential absorption lidar (DIAL) working in the near-infrared (NIR) spectral region is a suitable technique. For measuring the light absorption by single spectral lines in the 817nm band of water vapor, the laser emission is predominated for the use of Ti:Sapphire as laser medium. We present a new concept of transversely pumping a Ti:Sapphire crystal to generate high power NIR laser emission directly from a laser resonator without amplification stage. This setup allows for a high output power at repetitions rates up to 100Hz or even more due to the enhanced cooling situation for the laser rod. It is, because of its compactness, also suitable for mobile applications. We also show a concept, how this resonator can be locked to two seeding DIAL wavelengths at the same time.</p> <p>[1] Vogelmann, H., Sussmann, R., Trickl, T., and Reichert, A.: Spatiotemporal variability of water vapor investigated using lidar and FTIR vertical soundings above the Zugspitze, Atmos. Chem. Phys., 15, 3135-3148, 2015.</p>

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