A New Equation of State for H2O Ice Ih
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Proton Ordering and Reactivity of Ice
1 Proton ordering and reactivity of ice Zamaan Raza Department of Chemistry University College London Thesis submitted for the degree of Doctor of Philosophy September 2012 2 I, Zamaan Raza, confirm that the work presented in this thesis is my own. Where information has been derived from other sources, I confirm that this has been indicated in the thesis. 3 For Chryselle, without whom I would never have made it this far. 4 I would like to thank my supervisors, Dr Ben Slater and Prof Angelos Michaelides for their patient guidance and help, particularly in light of the fact that I was woefully unprepared when I started. I would also like to express my gratitude to Dr Florian Schiffmann for his indispens- able advice on CP2K and quantum chemistry, Dr Alexei Sokol for various discussions on quantum mechanics, Dr Dario Alfé for his incredibly expensive DMC calculations, Drs Jiri Klimeš and Erlend Davidson for advice on VASP, Matt Watkins for help with CP2K, Christoph Salzmann for discussions on ice, Dr Stefan Bromley for allowing me to work with him in Barcelona and Drs Aron Walsh, Stephen Shevlin, Matthew Farrow and David Scanlon for general help, advice and tolerance. Thanks and also apologies to Stephen Cox, with whom I have collaborated, but have been unable to contribute as much as I should have. Doing a PhD is an isolating experience (more so in the Kathleen Lonsdale building), so I would like to thank my fellow students and friends for making it tolerable: Richard, Tiffany, and Chryselle. Finally, I would like to acknowledge UCL for my funding via a DTA and computing time on Legion, the Materials Chemistry Consortium (MCC) for computing time on HECToR and HPC-Europa2 for the opportunity to work in Barcelona. -
Arxiv:2004.08465V2 [Cond-Mat.Stat-Mech] 11 May 2020
Phase equilibrium of liquid water and hexagonal ice from enhanced sampling molecular dynamics simulations Pablo M. Piaggi1 and Roberto Car2 1)Department of Chemistry, Princeton University, Princeton, NJ 08544, USA a) 2)Department of Chemistry and Department of Physics, Princeton University, Princeton, NJ 08544, USA (Dated: 13 May 2020) We study the phase equilibrium between liquid water and ice Ih modeled by the TIP4P/Ice interatomic potential using enhanced sampling molecular dynamics simulations. Our approach is based on the calculation of ice Ih-liquid free energy differences from simulations that visit reversibly both phases. The reversible interconversion is achieved by introducing a static bias potential as a function of an order parameter. The order parameter was tailored to crystallize the hexagonal diamond structure of oxygen in ice Ih. We analyze the effect of the system size on the ice Ih-liquid free energy differences and we obtain a melting temperature of 270 K in the thermodynamic limit. This result is in agreement with estimates from thermodynamic integration (272 K) and coexistence simulations (270 K). Since the order parameter does not include information about the coordinates of the protons, the spontaneously formed solid configurations contain proton disorder as expected for ice Ih. I. INTRODUCTION ture forms in an orientation compatible with the simulation box9. The study of phase equilibria using computer simulations is of central importance to understand the behavior of a given model. However, finding the thermodynamic condition at II. CRYSTAL STRUCTURE OF ICE Ih which two or more phases coexist is particularly hard in the presence of first order phase transitions. -
Herbert Ponting; Picturing the Great White South
City University of New York (CUNY) CUNY Academic Works Dissertations and Theses City College of New York 2014 Herbert Ponting; Picturing the Great White South Maggie Downing CUNY City College How does access to this work benefit ou?y Let us know! More information about this work at: https://academicworks.cuny.edu/cc_etds_theses/328 Discover additional works at: https://academicworks.cuny.edu This work is made publicly available by the City University of New York (CUNY). Contact: [email protected] The City College of New York Herbert Ponting: Picturing the Great White South Submitted in partial fulfillment of the requirements for the degree of Master of Arts of the City College of the City University of New York. by Maggie Downing New York, New York May 2014 Dedicated to my Mother Acknowledgments I wish to thank, first and foremost my advisor and mentor, Prof. Ellen Handy. This thesis would never have been possible without her continuing support and guidance throughout my career at City College, and her patience and dedication during the writing process. I would also like to thank the rest of my thesis committee, Prof. Lise Kjaer and Prof. Craig Houser for their ongoing support and advice. This thesis was made possible with the assistance of everyone who was a part of the Connor Study Abroad Fellowship committee, which allowed me to travel abroad to the Scott Polar Research Institute in Cambridge, UK. Special thanks goes to Moe Liu- D'Albero, Director of Budget and Operations for the Division of the Humanities and the Arts, who worked the bureaucratic college award system to get the funds to me in time. -
Evasive Ice X and Heavy Fermion Ice XII: Facts and Fiction About High
Physica B 265 (1999) 113—120 Evasive ice X and heavy fermion ice XII: facts and fiction about high-pressure ices W.B. Holzapfel* Fachbereich Physik, Universita( t-GH Paderborn, D-33095 Paderborn, Germany Abstract Recent theoretical and experimental results on the structure and dynamics of ice in wide regions of pressure and temperature are compared with earlier models and predictions to illustrate the evasive nature of ice X, which was originally introduced as completely ordered form of ice with short single centred hydrogen bonds isostructural CuO. Due to the lack of experimental information on the proton ordering in the pressure and temperature region for the possible occurrence of ice X, effects of thermal and quantum delocalization are discussed with respect to the shape of the phase diagram and other structural models consistent with present optical and X-ray data for this region. Theoretical evidences for an additional orthorhombic modification (ice XI) at higher pressures are confronted with various reasons supporting a delocalization of the protons in the form of a heavy fermion system with very unique physical properties characterizing this fictitious new phase of ice XII. ( 1999 Elsevier Science B.V. All rights reserved. Keywords: Ices; Hydrogen bonds; Phase diagram; Equation of states 1. Introduction tunnelling [2]. Detailed Raman studies on HO and DO ice VIII to pressures in the range of The first in situ X-ray studies on HO and DO 50 GPa [3] revealed the expected softening in the ice VII under pressures up to 20 GPa [1] together molecular stretching modes and led to the deter- with a simple twin Morse potential (TMP) model mination of a critical O—H—O bond length of " for protons or deuterons in hydrogen bonds [2] R# 232 pm, where the central barrier of the effec- allowed almost 26 years ago first speculations tive double-well potential should disappear [4]. -
Novel Hydraulic Structures and Water Management in Iran: a Historical Perspective
Novel hydraulic structures and water management in Iran: A historical perspective Shahram Khora Sanizadeh Department of Water Resources Research, Water Research Institute������, Iran Summary. Iran is located in an arid, semi-arid region. Due to the unfavorable distribution of surface water, to fulfill water demands and fluctuation of yearly seasonal streams, Iranian people have tried to provide a better condition for utilization of water as a vital matter. This paper intends to acquaint the readers with some of the famous Iranian historical water monuments. Keywords. Historic – Water – Monuments – Iran – Qanat – Ab anbar – Dam. Structures hydrauliques et gestion de l’eau en Iran : une perspective historique Résumé. L’Iran est situé dans une région aride, semi-aride. La répartition défavorable des eaux de surface a conduit la population iranienne à créer de meilleures conditions d’utilisation d’une ressource aussi vitale que l’eau pour faire face à la demande et aux fluctuations des débits saisonniers annuels. Ce travail vise à faire connaître certains des monuments hydrauliques historiques parmi les plus fameux de l’Iran. Mots-clés. Historique – Eau – Monuments – Iran – Qanat – Ab anbar – Barrage. I - Introduction Iran is located in an arid, semi-arid region. Due to the unfavorable distribution of surface water, to fulfill water demands and fluctuation of yearly seasonal streams, Iranian people have tried to provide a better condition for utilization of water as a vital matter. Iran is located in the south of Asia between 44º 02´ and 63º 20´ eastern longitude and 25º 03´ to 39º 46´ northern latitude. The country covers an area of about 1.648 million km2. -
11Th International Conference on the Physics and Chemistry of Ice, PCI
11th International Conference on the Physics and Chemistry of Ice (PCI-2006) Bremerhaven, Germany, 23-28 July 2006 Abstracts _______________________________________________ Edited by Frank Wilhelms and Werner F. Kuhs Ber. Polarforsch. Meeresforsch. 549 (2007) ISSN 1618-3193 Frank Wilhelms, Alfred-Wegener-Institut für Polar- und Meeresforschung, Columbusstrasse, D-27568 Bremerhaven, Germany Werner F. Kuhs, Universität Göttingen, GZG, Abt. Kristallographie Goldschmidtstr. 1, D-37077 Göttingen, Germany Preface The 11th International Conference on the Physics and Chemistry of Ice (PCI- 2006) took place in Bremerhaven, Germany, 23-28 July 2006. It was jointly organized by the University of Göttingen and the Alfred-Wegener-Institute (AWI), the main German institution for polar research. The attendance was higher than ever with 157 scientists from 20 nations highlighting the ever increasing interest in the various frozen forms of water. As the preceding conferences PCI-2006 was organized under the auspices of an International Scientific Committee. This committee was led for many years by John W. Glen and is chaired since 2002 by Stephen H. Kirby. Professor John W. Glen was honoured during PCI-2006 for his seminal contributions to the field of ice physics and his four decades of dedicated leadership of the International Conferences on the Physics and Chemistry of Ice. The members of the International Scientific Committee preparing PCI-2006 were J.Paul Devlin, John W. Glen, Takeo Hondoh, Stephen H. Kirby, Werner F. Kuhs, Norikazu Maeno, Victor F. Petrenko, Patricia L.M. Plummer, and John S. Tse; the final program was the responsibility of Werner F. Kuhs. The oral presentations were given in the premises of the Deutsches Schiffahrtsmuseum (DSM) a few meters away from the Alfred-Wegener-Institute. -
Anomalous Pressure-Induced Transition(S) in Ice XI
PHYSICAL REVIEW LETTERS week ending VOLUME 92, NUMBER 10 12 MARCH 2004 Anomalous Pressure-Induced Transition(s) in Ice XI Koichiro Umemoto,1,2 Renata M. Wentzcovitch,1,2 Stefano Baroni,1 and Stefano de Gironcoli1 1SISSA–Scuola Internazionale Superiore di Studi Avanzati and INFM-DEMOCRITOS National Simulation Center, I-34014 Trieste, Italy 2Department of Chemical Engineering and Material Science and Minnesota Supercomputer Institute for Digital Simulation and Advanced Computation, University of Minnesota, Minneapolis, Minnesota 55455, USA (Received 23 May 2003; published 12 March 2004) The effects of pressure on the structure of ice XI — an ordered form of the phase of ice Ih, which is known to amorphize under pressure — are investigated theoretically using density-functional theory. We find that pressure induces a mechanical instability, which is initiated by the softening of an acoustic phonon occurring at an incommensurate wavelength, followed by the collapse of the entire acoustic band and by the violation of the Born stability criteria. It is argued that phonon collapse may be a quite general feature of pressure-induced amorphization. The implications of our findings for the amorph- ization of ice Ih are also discussed. DOI: 10.1103/PhysRevLett.92.105502 PACS numbers: 63.20.Dj, 64.70.Rh, 83.80.Nb Ice Ih is the first system which was observed to effects of hydrogen disorder, and draw a parallel between amorphize under pressure [1]. It was soon argued that our results and those previously obtained in -quartz. this behavior was related with the negative Clapeyron The structure of ice Ih consists of a hexagonal diamond slope of the melting line of ice Ih and that amorphiza- lattice of oxygen atoms with one hydrogen atom placed at tion would occur at the metastable extension of this line random in one of the two energy minima existing in in the stability field of another high-pressure phase. -
Ice Engineering and Avalanche Forecasting and Control Gold, L
NRC Publications Archive Archives des publications du CNRC Ice engineering and avalanche forecasting and control Gold, L. W.; Williams, G. P. This publication could be one of several versions: author’s original, accepted manuscript or the publisher’s version. / La version de cette publication peut être l’une des suivantes : la version prépublication de l’auteur, la version acceptée du manuscrit ou la version de l’éditeur. Publisher’s version / Version de l'éditeur: Technical Memorandum (National Research Council of Canada. Division of Building Research); no. DBR-TM-98, 1969-10-23 NRC Publications Archive Record / Notice des Archives des publications du CNRC : https://nrc-publications.canada.ca/eng/view/object/?id=50c4a1f1-0608-4db2-9ccd-74b038ef41bb https://publications-cnrc.canada.ca/fra/voir/objet/?id=50c4a1f1-0608-4db2-9ccd-74b038ef41bb Access and use of this website and the material on it are subject to the Terms and Conditions set forth at https://nrc-publications.canada.ca/eng/copyright READ THESE TERMS AND CONDITIONS CAREFULLY BEFORE USING THIS WEBSITE. L’accès à ce site Web et l’utilisation de son contenu sont assujettis aux conditions présentées dans le site https://publications-cnrc.canada.ca/fra/droits LISEZ CES CONDITIONS ATTENTIVEMENT AVANT D’UTILISER CE SITE WEB. Questions? Contact the NRC Publications Archive team at [email protected]. If you wish to email the authors directly, please see the first page of the publication for their contact information. Vous avez des questions? Nous pouvons vous aider. Pour communiquer directement avec un auteur, consultez la première page de la revue dans laquelle son article a été publié afin de trouver ses coordonnées. -
Evaluations of Cultural Properties
WHC-04/28COM/INF.14A UNESCO WORLD HERITAGE CONVENTION WORLD HERITAGE COMMITTEE 28th ordinary session (28 June – 7 July 2004) Suzhou (China) EVALUATIONS OF CULTURAL PROPERTIES Prepared by the International Council on Monuments and Sites (ICOMOS) The IUCN and ICOMOS evaluations are made available to members of the World Heritage Committee. A small number of additional copies are also available from the secretariat. Thank you 2004 WORLD HERITAGE LIST Nominations 2004 I NOMINATIONS OF MIXED PROPERTIES TO THE WORLD HERITAGE LIST A Europe – North America Extensions of properties inscribed on the World Heritage List United Kingdom – [N/C 387 bis] - St Kilda (Hirta) 1 B Latin America and the Caribbean New nominations Ecuador – [N/C 1124] - Cajas Lakes and the Ruins of Paredones 5 II NOMINATIONS OF CULTURAL PROPERTIES TO THE WORLD HERITAGE LIST A Africa New nominations Mali – [C 1139] - Tomb of Askia 9 Togo – [C 1140] - Koutammakou, the Land of the Batammariba 13 B Arab States New nominations Jordan – [C 1093] - Um er-Rasas (Kastron Mefa'a) 17 Properties deferred or referred back by previous sessions of the World Heritage Committee Morocco – [C 1058 rev] See addendum: - Portuguese City of El Jadida (Mazagan) WHC-04/28.COM/INF.15A Add C Asia – Pacific New nominations Australia – [C 1131] - Royal Exhibition Building and Carlton Gardens 19 China – [C 1135] - Capital Cities and Tombs of the Ancient Koguryo Kingdom 24 India – [C 1101] - Champaner-Pavagadh Archaeological Park 26 Iran – [C 1106] - Pasargadae (Pasargad) 30 Japan – [C 1142] - Sacred Sites -
Performance Analysis of Ice-Relative Upward-Looking Doppler Navigation of Underwater Vehicles Beneath Moving Sea Ice
Article Performance Analysis of Ice-Relative Upward-Looking Doppler Navigation of Underwater Vehicles Beneath Moving Sea Ice Laughlin D. L. Barker 1,2 and Louis L. Whitcomb 1,* 1 Department of Mechanical Engineering, Johns Hopkins University, Baltimore, MD 21218, USA; [email protected] 2 Department of Marine Operations, Monterey Bay Aquarium Research Institute, Moss Landing, CA 95039, USA * Correspondence: [email protected] Abstract: This paper addresses the problem of ice-relative underwater robotic vehicle navigation relative to moving or stationary contiguous sea ice. A review of previously-reported under-ice navigation methods is given, as well as motivation for the use of under-ice robotic vehicles with precision navigation capabilities. We then describe our proposed approach, which employs two or more satellite navigation beacons atop the sea ice along with other precision vehicle and ship mounted navigation sensors to estimate vehicle, ice, and ship states by means of an Extended Kalman Filter. A performances sensitivity analysis for a simulated 7.7 km under ice survey is reported. The number and the location of ice deployed satellite beacons, rotational and translational ice velocity, and separation of ship-based acoustic range sensors are varied, and their effects on estimate error Citation: Barker, L.D.L.; Whitcomb, and uncertainty are examined. Results suggest that increasing the number and/or separation of L.L. Performance Analysis of ice-deployed satellite beacons reduces estimate uncertainty, whereas increasing separation of ship- Ice-Relative Upward-Looking based acoustic range sensors has little impact on estimate uncertainty. Decreasing ice velocity is also Doppler Navigation of Underwater correlated with reduced estimate uncertainty. -