scholarly journals The Takahashi–Bassett Era of Mineral Physics at Rochester in the 1960s

Minerals ◽  
2020 ◽  
Vol 10 (4) ◽  
pp. 344
Author(s):  
William A. Bassett
Keyword(s):  
High Pressure ◽  
High Pressures ◽  
Faculty Position ◽  
Mineral Physics ◽  
High Pressure High Temperature ◽  
High Pressures And Temperatures ◽  
The 1960S ◽  
Talented Students ◽  
The University

The late Taro Takahashi earned a particularly well-deserved reputation for his research at Lamont Geological Observatory on carbon dioxide and its transfer between the atmosphere and the oceans. However, his accomplishments in Mineral Physics, the field embracing the high-pressure–high-temperature properties of materials, has received less attention in spite of his major contributions to this emerging field focused on the interiors of Earth and other planets. In 1963, I was thrilled when he was offered a faculty position in the Geology Department at the University of Rochester, where I had recently joined the faculty. Taro and I worked together for the next 10 years with our talented students exploring the blossoming field just becoming known as Mineral Physics, the name introduced by Orson Anderson and Ed Schreiber, who were also engaged in measuring physical properties at high pressures and temperatures. While their specialty was ultrasonic velocities in minerals subjected to high pressures and temperatures, ours was the determination of crystal structures, compressibilities, and densities of such minerals as iron, its alloys, and silicate minerals, especially those synthesized at high-pressure, such as silicates with the spinel structure. These were materials expected to be found in the Earth’s interior and could therefore provide background for the interpretation of geophysical observations.

scholarly journals My Career as a Mineral Physicist at Stony Brook: 1976–2019

Minerals ◽  
2019 ◽  
Vol 9 (12) ◽  
pp. 761
Author(s):  
Robert Cooper Liebermann
Keyword(s):  
High Pressure ◽  
Graduate Students ◽  
High Pressures ◽  
Physics Institute ◽  
Faculty Position ◽  
Mineral Physics ◽  
Princeton University ◽  
Structural Analogues ◽  
High Pressures And Temperatures ◽  
The U.S

In 1976, I took up a faculty position in the Department of Geosciences of Stony Brook University. Over the next half century, in collaboration with graduate students from the U.S., China and Russia and postdoctoral colleagues from Australia, France and Japan, we pursued studies of the elastic properties of minerals (and their structural analogues) at high pressures and temperatures. In the 1980s, together with Donald Weidner, we established the Stony Brook High Pressure Laboratory and the Mineral Physics Institute. In 1991, in collaboration with Alexandra Navrotsky at Princeton University and Charles Prewitt at the Geophysical Laboratory, we founded the NSF Science and Technology Center for High Pressure Research.

Hochdruckumwandlungen von Cer(III)Orthovanadat(V), CeVO4 / High-Pressure Transformations of Cerium(III) Orthovanadate(V), CeVO4

1990 ◽  
Vol 45 (5) ◽  
pp. 598-602 ◽  
Author(s):  
Klaus-Jürgen Range ◽  
Helmut Meister ◽  
Ulrich Klement
Keyword(s):  
High Pressure ◽  
Triple Point ◽  
High Pressures ◽  
Its Region ◽  
Normal Pressure ◽  
Crystal Data ◽  
High Pressures And Temperatures ◽  
Zircon Type ◽  
High Pressure Apparatus

The polymorphism of CeVO4 was investigated at high pressures and temperatures in a Belttype high-pressure apparatus. In addition to the normal-pressure modification CeVO4— I with zircon-type structure two high-pressure modifications have been found, viz. monazite-type CeVO4—II and scheelite-type CeVO4—III. CeVO4—II is stable between 1 bar and 30 kbar at 1300 °C. Its region of existence decreases rapidly at lower temperatures. From the observed p,T-relations for the I-II and I-III transformations a triple point CeVO4—I,II,III at about 27 kbar, 500 °C can be estimated. For kinetic reasons, however, the experimental determination of phase relations becomes difficult at temperatures below 600 °C.The crystal structures of CeVO4— I and —II have been refined from single-crystal data. Crystallographic data for the three modifications are given and discussed (CeVO4—I: I 41/amd, a = 7.383(1)Å, c = 6.485(1)Å, Z = 4; CeVO4—II: P21/n, a = 7.003(1)Å, b = 7.227(1)Å, c = 6.685(1)Å, β = 105.13(1)°, Z = 4; CeVO4—III: I 41/α, a = 5.1645(2)Å, c = 11.8482(7)Å, Z = 4).

Near Infrared Absorption of Pure n-Heptane between 5000 cm 1 and 6500 cm-1 to High Pressures and Temperatures

1983 ◽  
Vol 38 (5) ◽  
pp. 528-532 ◽  
Author(s):  
M. Buback ◽  
A. A. Harfoush
Keyword(s):  
High Pressure ◽  
Infrared Absorption ◽  
Near Infrared ◽  
High Pressures ◽  
Kinetic Studies ◽  
Molar Absorptivity ◽  
High Pressure High Temperature ◽  
High Pressures And Temperatures ◽  
Combination Mode ◽  
Better Than

The near infrared absorption of pure n-heptane between 5000 cm-1 and 6500 cm-1 was measured up to 250 °C and to pressures of 2000 bar. The procedure for measuring vibrational intensities at high pressures and temperatures with a precision of better than ± 1% is described. The integrated “molar absorptivity of the combination mode va + vs of the methylene stretching fundamentals turns out to be independent of temperature and density. This offers important applications for high-pressure high-temperature thermodynamic and kinetic studies via quanti­tative near infrared spectroscopy.

Infrared Absorption of Concentrated Aqueous NaClO4 Solutions to High Pressures and Temperatures

1981 ◽  
Vol 36 (11) ◽  
pp. 1169-1176 ◽  
Author(s):  
V. M. Valyashko ◽  
M. Buback ◽  
E. U. Franck
Keyword(s):  
High Pressure ◽  
High Temperature ◽  
Infrared Absorption ◽  
High Pressures ◽  
Molar Absorptivity ◽  
Wave Number ◽  
Water Molecules ◽  
High Pressure High Temperature ◽  
High Pressures And Temperatures ◽  
Band Separation

The infrared absorption of the O-D stretching fundamental of HDO in concentrated aqueous (HDO/H2O)NaClO4 solutions up to 20 mole% salt has been measured. The data for the wave-number of maximum absorption, ν̅(max), and for the integrated molar absorptivity B up to pressures and temperatures of 2800 bar and 250 °C, respectively, demonstrate the importance of non-hydrogen-bonded interactions in aqueous perchlorate solutions. A non-continuous dis­tribution of the states of water molecules is clearly evident from the experimental spectra. A band separation using three Gaussian components proves the close similarity between the high-pressure high-temperature vibrational O-D infrared spectra of aqueous perchlorate solutions and the O-D Raman spectra of water and aqueous solutions.Results of the band separation together with literature Raman data provide some evidence that a transition from “water-like” to “melt-like” behaviour occurs in a fairly narrow concentra­tion region between 10 and 15 mole% salt.

scholarly journals The thermal conductivity of the Earth's core and implications for its thermal and compositional evolution

2020 ◽  
Author(s):  
Kenji Ohta ◽  
Kei Hirose
Keyword(s):  
Thermal Conductivity ◽  
High Pressure ◽  
Thermal History ◽  
Diamond Anvil Cell ◽  
High Pressures ◽  
Iron Alloys ◽  
Compositional Evolution ◽  
The Earth ◽  
Diamond Anvil ◽  
High Pressures And Temperatures

Abstract Precise determinations of the thermal conductivity of iron alloys at high pressures and temperatures are essential for understanding the thermal history and dynamics of the metallic cores of the Earth. We review relevant high-pressure experiments using a diamond-anvil cell and discuss implications of high core conductivity for its thermal and compositional evolution.

On the Negative Excess Isotherms for Methane Adsorption at High Pressure: Modeling and Experiment

SPE Journal ◽  
2019 ◽  
Vol 24 (06) ◽  
pp. 2504-2525 ◽  
Author(s):  
Jing Li ◽  
Keliu Wu ◽  
Zhangxin Chen ◽  
Kun Wang ◽  
Jia Luo ◽  
...  
Keyword(s):  
High Pressure ◽  
Mass Balance ◽  
High Pressures ◽  
Pore Wall ◽  
Void Volume ◽  
Excess Adsorption ◽  
Experimental Conditions ◽  
Accessible Volume ◽  
Adsorbed Phase

Summary An excess adsorption amount obtained in experiments is always determined by mass balance with a void volume measured by helium (He) –expansion tests. However, He, with a small kinetic diameter, can penetrate into narrow pores in porous media that are inaccessible to adsorbate gases [e.g., methane (CH4)]. Thus, the actual accessible volume for a specific adsorbate is always overestimated by an He–based void volume; such overestimation directly leads to errors in the determination of excess isotherms in the laboratory, such as “negative isotherms” for gas adsorption at high pressures, which further affects an accurate description of total gas in place (GIP) for shale–gas reservoirs. In this work, the mass balance for determining the adsorbed amount is rewritten, and two particular concepts, an “apparent excess adsorption” and an “actual excess adsorption,” are considered. Apparent adsorption is directly determined by an He–based volume, corresponding to the traditional treatment in experimental conditions, whereas actual adsorption is determined by an adsorbate–accessible volume, where pore–wall potential is always nonpositive (i.e., an attractive molecule/pore–wall interaction). Results show the following: The apparent excess isotherm determined by the He–based volume gradually becomes negative at high pressures, but the actual one determined by the adsorbate–accessible volume always remains positive.The negative adsorption phenomenon in the apparent excess isotherm is a result of the overestimation in the adsorbate–accessible volume, and a larger overestimation leads to an earlier appearance of this negative adsorption.The positive amount in the actual excess isotherm indicates that the adsorbed phase is always denser than the bulk gas because of the molecule/pore–wall attraction aiding the compression of the adsorbed molecules. Practically, an overestimation in pore volume (PV) is only 3.74% for our studied sample, but it leads to an underestimation reaching up to 22.1% in the actual excess amount at geologic conditions (i.e., approximately 47 MPa and approximately 384 K). Such an overestimation in PV also underestimates the proportions of the adsorbed–gas amount to the free–gas amount and to the total GIP. Therefore, our present work underlines the importance of a void volume in the determination of adsorption isotherms; moreover, we establish a path for a more–accurate evaluation of gas storage in geologic shale reservoirs with high pressure.

scholarly journals Ab initio Determination of the Phase Diagram of CO2 at High Pressures and Temperatures

2020 ◽  
Vol 124 (9) ◽  
Author(s):  
Beatriz H. Cogollo-Olivo ◽  
Sananda Biswas ◽  
Sandro Scandolo ◽  
Javier A. Montoya
Keyword(s):  
Phase Diagram ◽  
Ab Initio ◽  
High Pressures ◽  
High Pressures And Temperatures

The theory of ionisation measurements in gases at high pressures

1934 ◽  
Vol 30 (1) ◽  
pp. 80-101 ◽  
Author(s):  
D. E. Lea
Keyword(s):  
High Pressure ◽  
Experimental Determination ◽  
Experimental Technique ◽  
Alpha Particle ◽  
Reasonable Agreement ◽  
High Pressures ◽  
Industrial Research ◽  
Heavy Nuclei ◽  
Nuclear Tracks

The columnar theory developed by Jaffé to account for the recombination of ions in alpha particle tracks is extended to beta rays by taking account of the clusters of secondary ionisation. Reasonable agreement is obtained with experiment. Recombination in proton tracks produced in hydrogen by neutrons is shown to be in agreement with the columnar theory, but in the case of nitrogen nuclear tracks in nitrogen the recombination is only a hundredth of that predicted by the theory. An explanation of this effect is advanced, and it is suggested that recombination is likely to be abnormally small for all heavy nuclei of velocities not exceeding 5 × 108 cm. per sec.An experimental determination of the coefficient of recombination of ions in nitrogen and hydrogen at pressures of 20, 40 and 90 atmospheres is reported.My thanks are due to Dr Chadwick for interest in this work, and to Dr Gray and Dr Tarrant for advice on the experimental technique of high pressure ionisation measurements. I am indebted also to the Department of Scientific and Industrial Research for a maintenance grant.

Formation of two crystal modifications of Fe7C3−x at 5.5 GPa

2019 ◽  
Vol 52 (6) ◽  
pp. 1378-1384
Author(s):  
Sergey Gromilov ◽  
Anatoly Chepurov ◽  
Valeri Sonin ◽  
Egor Zhimulev ◽  
Aleksandr Sukhikh ◽  
...  
Keyword(s):  
High Pressure ◽  
High Pressures ◽  
Experimental Studies ◽  
X Ray Diffraction ◽  
High Iron Content ◽  
X Ray ◽  
High Pressure High Temperature ◽  
Micro Analysis ◽  
Crystal Modifications ◽  
High Pressure Apparatus

The Fe–C system, which is widely used to grow commercial high-pressure–high-temperature diamond monocrystals, is rather complicated due to the formation of carbides. The carbide Fe3C is a normal run product, but the pressure at which Fe7C3 carbide becomes stable is a subject of discussion. This paper demonstrates the synthesis of Fe7C3 carbide and its detailed study using single-crystal and powder X-ray diffraction, as well as electron probe micro-analysis and scanning electron microscopy. The experiments were performed using a multiple-anvil high-pressure apparatus of `split-sphere' (BARS) type at a pressure of 5.5 GPa and a temperature of 1623 K. Our results show that in the Fe–C system, in addition to diamond, a phase that corresponds to the Fe7C3 carbide was synthesized. This means that both carbides (Fe7C3 and Fe3C) are stable at 5.5 GPa. Two crystal phases are described, Fe14C6 and Fe28C12−x . Fe14C6 is based on the well known rhombic structure of Fe7C3, while Fe28C12−x has a different packing order of Fe6C polyhedrons. The results obtained in this study should be taken into account when synthesizing and growing diamond at high pressures and temperatures in metal–carbon systems with a high iron content, as well as when conducting experimental studies on the synthesis of diamond directly from carbide.

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