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Title: Density hysteresis of heavy water confined in a nanoporous silica matrix

Abstract

A neutron scattering technique was developed to measure the density of heavy water confined in a nanoporous silica matrix in a temperature-pressure range, from 300 to 130 K and from 1 to 2,900 bars, where bulk water will crystalize. We observed a prominent hysteresis phenomenon in the measured density profiles between warming and cooling scans above 1,000 bars. We inter- pret this hysteresis phenomenon as support (although not a proof) of the hypothetical existence of a first-order liquid liquid phase transition of water that would exist in the macroscopic system if crystallization could be avoided in the relevant phase region. Moreover, the density data we obtained for the confined heavy water under these conditions are valuable to large communities in biology and earth and planetary sciences interested in phenomena in which nanometer-sized water layers are involved.

Authors:
 [1];  [2];  [1];  [3];  [3];  [1];  [1];  [1]
  1. ORNL
  2. National Institute of Standards and Technology (NIST)
  3. National Taiwan University
Publication Date:
Research Org.:
Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
1023333
DOE Contract Number:
DE-AC05-00OR22725
Resource Type:
Journal Article
Resource Relation:
Journal Name: Proceedings of the National Academy of Sciences; Journal Volume: 108; Journal Issue: 30
Country of Publication:
United States
Language:
English
Subject:
72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS; BIOLOGY; COMMUNITIES; CRYSTALLIZATION; HEAVY WATER; HYSTERESIS; NEUTRONS; SCATTERING; SILICA; WATER; confined water; neutron scattering; equation of state; liquid-liquid critical phenomenon

Citation Formats

Zhang, Yang, Faraone, Antonio, Kamitakahara, William, Liu, Kao-Hsiang, Mou, Chung-Yuan, Leao, Juscelino B, Chang, Sung C, and Chen, Sow-hsin H. Density hysteresis of heavy water confined in a nanoporous silica matrix. United States: N. p., 2011. Web. doi:10.1073/pnas.1100238108.
Zhang, Yang, Faraone, Antonio, Kamitakahara, William, Liu, Kao-Hsiang, Mou, Chung-Yuan, Leao, Juscelino B, Chang, Sung C, & Chen, Sow-hsin H. Density hysteresis of heavy water confined in a nanoporous silica matrix. United States. doi:10.1073/pnas.1100238108.
Zhang, Yang, Faraone, Antonio, Kamitakahara, William, Liu, Kao-Hsiang, Mou, Chung-Yuan, Leao, Juscelino B, Chang, Sung C, and Chen, Sow-hsin H. Sat . "Density hysteresis of heavy water confined in a nanoporous silica matrix". United States. doi:10.1073/pnas.1100238108.
@article{osti_1023333,
title = {Density hysteresis of heavy water confined in a nanoporous silica matrix},
author = {Zhang, Yang and Faraone, Antonio and Kamitakahara, William and Liu, Kao-Hsiang and Mou, Chung-Yuan and Leao, Juscelino B and Chang, Sung C and Chen, Sow-hsin H},
abstractNote = {A neutron scattering technique was developed to measure the density of heavy water confined in a nanoporous silica matrix in a temperature-pressure range, from 300 to 130 K and from 1 to 2,900 bars, where bulk water will crystalize. We observed a prominent hysteresis phenomenon in the measured density profiles between warming and cooling scans above 1,000 bars. We inter- pret this hysteresis phenomenon as support (although not a proof) of the hypothetical existence of a first-order liquid liquid phase transition of water that would exist in the macroscopic system if crystallization could be avoided in the relevant phase region. Moreover, the density data we obtained for the confined heavy water under these conditions are valuable to large communities in biology and earth and planetary sciences interested in phenomena in which nanometer-sized water layers are involved.},
doi = {10.1073/pnas.1100238108},
journal = {Proceedings of the National Academy of Sciences},
number = 30,
volume = 108,
place = {United States},
year = {Sat Jan 01 00:00:00 EST 2011},
month = {Sat Jan 01 00:00:00 EST 2011}
}
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