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Dielectric Properties of Water Under Extreme Conditions and Transport of Carbonates in the Deep Earth
Dielectric properties of water under extreme conditions and transport of carbonates in the deep Earth Ding Pana,1, Leonardo Spanua,2, Brandon Harrisonb, Dimitri A. Sverjenskyb, and Giulia Gallia,c Departments of aChemistry and cPhysics, University of California, Davis, CA 95616; and bDepartment of Earth and Planetary Sciences, Johns Hopkins University, Baltimore, MD 21218 Edited by Russell J. Hemley, Carnegie Institution of Washington, Washington, DC, and approved February 22, 2013 (received for review December 11, 2012) Water is a major component of fluids in the Earth’s mantle, where We computed the dielectric constant of hot, compressed water its properties are substantially different from those at ambient using ab initio calculations (16, 17) with semilocal density func- conditions. At the pressures and temperatures of the mantle, tionals (18) and used our results to predict the solubility of car- experiments on aqueous fluids are challenging, and several fun- bonates in the Earth’s upper mantle, well into subduction zones. damental properties of water are poorly known; e.g., its dielectric We predict that MgCO3—an important mineral stable in the constant has not been measured. This lack of knowledge of water mantle up to 82 GPa (19) and insoluble in water at ambient dielectric properties greatly limits our ability to model water–rock conditions—becomes slightly soluble, at least millimolal levels at interactions and, in general, our understanding of aqueous fluids ∼10 GPa and 1,000 K. This result suggests that aqueous fluids below the Earth’s crust. Using ab initio molecular dynamics, we may be carbon hosts and transport carbonate in the deep Earth, computed the dielectric constant of water under the conditions of with important implications for the dynamics of the global car- the Earth’s upper mantle, and we predicted the solubility products bon cycle (20, 21). -
Genesis and Geographical Aspects of Glaciers - Vladimir M
HYDROLOGICAL CYCLE – Vol. IV - Genesis and Geographical Aspects of Glaciers - Vladimir M. Kotlyakov GENESIS AND GEOGRAPHICAL ASPECTS OF GLACIERS Vladimir M. Kotlyakov Institute of Geography, Russian Academy of Sciences, Moscow, Russia Keywords: Chionosphere, cryosphere, equilibrium line, firn line, glacial climate, glacier, glacierization, glaciosphere, ice, seasonal snow line, snow line, snow-patch Contents 1. Introduction 2. Properties of natural ice 3. Cryosphere, glaciosphere, chionosphere 4. Snow-patches and glaciers 5. Basic boundary levels of snow and ice 6. Measures of glacierization 7. Occurrence of glaciers 8. Present-day glacierization of the Arctic Glossary Bibliography Biographical Sketch Summary There exist ten crystal variants of ice and one amorphous form in Nature, however only one form ice-1 is distributed on the Earth. Ten other ice variants steadily exist only under a certain combinations of pressure, specific volume and temperature of medium, and those are not typical for our planet. The ice density is less than that of water by 9%, and owing to this water reservoirs are never totally frozen., Thus life is sustained in them during the winter time. As a rule, ice is much cleaner than water, and specific gas-ice compounds called as crystalline hydrates are found in ice. Among the different spheres surrounding our globe there are cryosphere (sphere of the cold), glaciosphere (sphere of snow and ice) and chionosphere (that part of the troposphere where the annual amount of solid precipitation exceeds their losses). The chionosphere envelopes the Earth with a shell 3 to 5 km in thickness. In the present epoch, snow and ice cover 14.2% of the planet’s surface and more than half of the land surface. -
Modeling the Ice VI to VII Phase Transition
Modeling the Ice VI to VII Phase Transition Dawn M. King 2009 NSF/REU PROJECT Physics Department University of Notre Dame Advisor: Dr. Kathie E. Newman July 31, 2009 Abstract Ice (solid water) is found in a number of different structures as a function of temperature and pressure. This project focuses on two forms: Ice VI (space group P 42=nmc) and Ice VII (space group Pn3m). An interesting feature of the structural phase transition from VI to VII is that both structures are \self clathrate," which means that each structure has two sublattices which interpenetrate each other but do not directly bond with each other. The goal is to understand the mechanism behind the phase transition; that is, is there a way these structures distort to become the other, or does the transition occur through the breaking of bonds followed by a migration of the water molecules to the new positions? In this project we model the transition first utilizing three dimensional visualization of each structure, then we mathematically develop a common coordinate system for the two structures. The last step will be to create a phenomenological Ising-like spin model of the system to capture the energetics of the transition. It is hoped the spin model can eventually be studied using either molecular dynamics or Monte Carlo simulations. 1 Overview of Ice The known existence of many solid states of water provides insight into the complexity of condensed matter in the universe. The familiarity of ice and the existence of many structures deem ice to be interesting in the development of techniques to understand phase transitions. -
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]. -
Ice-VII Inclusions in Diamonds: (18)
RESEARCH GEOCHEMISTRY on the basis of x-ray diffraction data that are presented here (Fig. 1). Ice-VII is a high-pressure form of water ice that is stable above 2.4 GPa Ice-VII inclusions in diamonds: (18). As we show, ice-VII (along with magnesian calcite, ilmenite, and halite) sensitively records high remnant pressures, which then also constrain Evidence for aqueous fluid the pressure and temperature where it has been encapsulated in the host diamond crystal, similar in Earth’s deep mantle to other micrometer-scale inclusions of soft molec- ular materials such as CO2,CO2-H2O, and N2 in diamond (19–23). O. Tschauner,1* S. Huang,1 E. Greenberg,2 V. B. Prakapenka,2 C. Ma,3 G. R. Rossman,3 By retaining high pressures, ice-VII inclusions A. H. Shen,4 D. Zhang,2,5 M. Newville,2 A. Lanzirotti,2 K. Tait6 monitor the former presence of H2O-rich fluid at different depths in the diamond-bearing man- Water-rich regions in Earth’s deeper mantle are suspected to play a key role in the global tle. Remnants of former fluids and melts have water budget and the mobility of heat-generating elements. We show that ice-VII occurs been found as inclusions in many diamonds as inclusions in natural diamond and serves as an indicator for such water-rich regions. through infrared (IR) spectroscopy and micro- Ice-VII, the residue of aqueous fluid present during growth of diamond, crystallizes upon chemical analysis (19, 22). On the basis of IR ascent of the host diamonds but remains at pressures as high as 24 gigapascals; it is spectroscopy, a lower-pressure ice phase, VI, has now recognized as a mineral by the International Mineralogical Association. -
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. -
Electromagnetism Based Atmospheric Ice Sensing Technique - a Conceptual Review
Int. Jnl. of Multiphysics Volume 6 · Number 4 · 2012 341 Electromagnetism based atmospheric ice sensing technique - A conceptual review Umair N. Mughal*, Muhammad S. Virk and M. Y. Mustafa High North Technology Center Department of Technology, Narvik University College, Narvik, Norway ABSTRACT Electromagnetic and vibrational properties of ice can be used to measure certain parameters such as ice thickness, type and icing rate. In this paper we present a review of the dielectric based measurement techniques for matter and the dielectric/spectroscopic properties of ice. Atmospheric Ice is a complex material with a variable dielectric constant, but precise calculation of this constant may form the basis for measurement of its other properties such as thickness and strength using some electromagnetic methods. Using time domain or frequency domain spectroscopic techniques, by measuring both the reflection and transmission characteristics of atmospheric ice in a particular frequency range, the desired parameters can be determined. Keywords: Atmospheric Ice, Sensor, Polar Molecule, Quantum Excitation, Spectroscopy, Dielectric 1. INTRODUCTION 1.1. ATMOSPHERIC ICING Atmospheric icing is the term used to describe the accretion of ice on structures or objects under certain conditions. This accretion can take place either due to freezing precipitation or freezing fog. It is primarily freezing fog that causes this accumulation which occurs mainly on mountaintops [16]. It depends mainly on the shape of the object, wind speed, temperature, liquid water content (amount of liquid water in a given volume of air) and droplet size distribution (conventionally known as the median volume diameter). The major effects of atmospheric icing on structure are the static ice loads, wind action on iced structure and dynamic effects. -
Properties of Ices at 0 K: a Test of Water Models J
THE JOURNAL OF CHEMICAL PHYSICS 127, 154518 ͑2007͒ Properties of ices at 0 K: A test of water models J. L. Aragones, E. G. Noya, J. L. F. Abascal, and C. Vega Departamento de Química Física, Facultad de Ciencias Químicas, Universidad Complutense, 28040 Madrid, Spain ͑Received 9 July 2007; accepted 27 July 2007; published online 19 October 2007͒ The properties of ices Ih, II, III, V, and VI at zero temperature and pressure are determined by computer simulation for several rigid water models ͑SPC/E, TIP5P, TIP4P/Ice, and TIP4P/2005͒. The energies of the different ices at zero temperature and pressure ͑relative to the ice II energy͒ are compared to the experimental results of Whalley ͓J. Chem. Phys. 81, 4087 ͑1984͔͒. TIP4P/Ice and TIP4P/2005 provide a qualitatively correct description of the relative energies of the ices at these conditions. In fact, only these two models provide the correct ordering in energies. For the SPC/E and TIP5P models, ice II is the most stable phase at zero temperature and pressure whereas for TIP4P/Ice and TIP4P/2005 ice Ih is the most stable polymorph. These results are in agreement with the relative stabilities found at higher temperatures. The solid-solid phase transitions at 0 K are determined. The predicted pressures are in good agreement with those obtained from free energy calculations. © 2007 American Institute of Physics. ͓DOI: 10.1063/1.2774986͔ I. INTRODUCTION 20th century, starting with the pioneering work of Tammann and Bridgman16–21 up to the recent discovery of ices XII, Taking into account the importance of water, it is not XIII, and XIV.22,23 Compared to the liquid, the study of ices surprising that thousands of simulation studies of water have by computer simulation has been more limited. -
Ice, Ice, Bambino September 8, 2020 1 / 45 Chemistry: 18 Shades of Ice
ICE Chemistry It gets bigger when it freezes! Biology Inupiaq (Alaska) have 100 Stuff lives in it in ice cores! Astrobiology names for ice! Enceladus? Climatology Albedo and Negative feedback Snowball Earth Astrophysics Clear at optical and also radio frequencies Ice as a good cosmic-ray target Cosmic-ray collisions with ice molecules visible from km-scale distances Dave Besson Ice, Ice, Bambino September 8, 2020 1 / 45 Chemistry: 18 Shades of Ice Terrestrial (familiar) ice: ”Ice 1h” 1996: Ice XII discovered 2006: Ice XIII and Ice XIV 2009: Ice XV found extremely high pressures and 143 C. At P>1.55×1012Pa (10M atm) ice!metal Ice, water, and water vapor coexist at the ‘triple point’: 273.16 K (0.01 C) at P=611.657 Pa. 1◦ ≡1/273.16 of difference b/w triple point and absolute zero (this defn will change in May 2019) Dave Besson Ice, Ice, Bambino September 8, 2020 2 / 45 Oddly, ρice < ρwater The fact that ice remains on top of water is what prevents lakes and rivers from freezing upwards from below! Dave Besson Ice, Ice, Bambino September 8, 2020 3 / 45 Socio-Cultural impact: Refrigeration, Curling, Marvel’s Iceman (2015-17) Refrigeration: 400 BC: Persian engineers carve ice in winter and store in 5000 m3 insulated (via ‘sarooj’ - sand, clay, egg whites, lime, goat hair, and ash) caverns in desert during summer Dave Besson Ice, Ice, Bambino September 8, 2020 4 / 45 Why is ice clear (blue) Dave Besson Ice, Ice, Bambino September 8, 2020 5 / 45 and snow white? and implications for climate.. -
The Water Polymorphism and the Liquid–Liquid Transition from Transport Data
Article The Water Polymorphism and the Liquid–Liquid Transition from Transport Data Francesco Mallamace 1,2,* , Domenico Mallamace 3 , Giuseppe Mensitieri 4 , Sow-Hsin Chen 1 , Paola Lanzafame 3 and Georgia Papanikolaou 3 1 Department of Nuclear Science and Engineering, Massachusetts Institute of Technology, Cambridge, MA 02139, USA; [email protected] 2 CNR ISC, UOS Roma Sapienza, Physics Department, Sapienza University of Rome, 00185 Roma, Italy 3 Departments of ChiBioFarAm Section of Industrial Chemistry, University of Messina, CASPE-INSTM, V.le F. Stagno d’Alcontres 31, 98166 Messina, Italy; [email protected] (D.M.); [email protected] (P.L.); [email protected] (G.P.) 4 Department of Chemical, Materials and Industrial Production Engineering, University of Naples Federico II, P.le Tecchio 80, 80125 Napoli, Italy; [email protected] * Correspondence: [email protected]; Tel.: +39-340-233-5213 Abstract: NMR spectroscopic literature data are used, in a wide temperature-pressure range (180–350 K and 0.1–400 MPa), to study the water polymorphism and the validity of the liquid–liquid transition (LLT) hypothesis. We have considered the self-diffusion coefficient DS and the reorientational correlation time tq (obtained from spin-lattice T1 relaxation times), measured, respectively, in bulk and emulsion liquid water from the stable to well inside the metastable supercooled region. As an effect of the hydrogen bond (HB) networking, the isobars of both these transport functions evolve with T by changing by several orders of magnitude, whereas their pressure dependence Citation: Mallamace, F.; Mallamace, become more and more pronounced at lower temperatures. Both these transport functions were D.; Mensitieri, G.; Chen, S.-H.; Lanzafame, P.; Papanikolaou, G. -
Ice-Seven (Ice VII)
Ice-seven (Ice VII) Ice-seven (ice VII) [1226] is formed from liquid water above 3 GPa by lowering its temperature to ambient temperatures (see Phase Diagram). It can be obtained at low temperature and ambient pressure by decompressing (D2O) ice-six below 95 K and is metastable over a wide range of pressure, transforming into LDA above 120 K [948]. Note that in this structural diagram the hydrogen bonding is ordered whereas in reality it is random (obeying the 'ice rules': two hydrogen atoms near each oxygen, one hydrogen atom on each O····O bond). As the H-O-H angle does not vary much from that of the isolated molecule, the hydrogen bonds are not straight (although shown so in the figures). The Ice VII unit cell, which forms cubic crystal ( , 224; Laue class symmetry m-3m) consists of two interpenetrating cubic ice lattices with hydrogen bonds passing through the center of the water hexamers and no connecting hydrogen-bonds between lattices. It has a density of about 1.65 g cm- 3 (at 2.5 GPa and 25 °C [8]), which is less than twice the cubic ice density as the intra-network O····O distances are 8% longer (at 0.1 MPa) to allow for the interpenetration. The cubic crystal (shown opposite) has cell dimensions 3.3501 Å (a, b, c, 90º, 90º, 90º; D2O, at 2.6 GPa and 22 °C [361]) and contains two water molecules. All molecules experience identical molecular environments. The hydrogen bonding is disordered and constantly changing as in hexagonal ice but ice-seven undergoes a proton disorder-order transition to ice-eight at about 5 °C; ice-seven and ice-eight having identical structures apart from the proton ordering. -