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.

scholarly journals Experimental determination of the isothermal compressibility of drilling fluids in high pressures and temperature

2019 ◽  
Author(s):  
Giuliano Andrei J. C. D. C. Mazoni ◽  
Paulo Roberto Ribeiro ◽  
Nara Angélica Policarpo ◽  
Nilo Ricardo Kim
Keyword(s):  
High Pressure ◽  
Experimental Determination ◽  
Isothermal Compressibility ◽  
High Pressures ◽  
Expansion Method ◽  
Measure Data ◽  
Drilling Fluids ◽  
Constant Composition ◽  
Volume Cell

The present work aims at the experimental determination of the isothermal compressibility of drilling fluids under high pressure and high temperature. For that, a high-resolution PVT (Pressure-Temperature-Volume) cell was used to measure data through the Constant Composition Expansion method. The isothermal compressibility values of the studied fluid were similar to the data found in the literature.

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.

Experimental Determination of the Equilibrium Water Content of CO2 at High Pressure and Low Temperature

2015 ◽  
Vol 60 (9) ◽  
pp. 2674-2683 ◽  
Author(s):  
Louis V. Jasperson ◽  
Jeong Won Kang ◽  
Chul Soo Lee ◽  
Don Macklin ◽  
Paul M. Mathias ◽  
...  
Keyword(s):  
High Pressure ◽  
Low Temperature ◽  
Experimental Determination ◽  
Water Content ◽  
Equilibrium Water Content

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.

FLOCCULATION OF ASPHALTENES AT HIGH PRESSURE. I. EXPERIMENTAL DETERMINATION OF THE ONSET OF FLOCCULATION

2001 ◽  
Vol 19 (9-10) ◽  
pp. 1155-1166 ◽  
Author(s):  
Horst Laux ◽  
Iradj Rahimian ◽  
Dieter Browarzik
Keyword(s):  
High Pressure ◽  
Experimental Determination
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