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James C. Holste - One of the best experts on this subject based on the ideXlab platform.
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Experimental P−T−ρ and Enthalpy-Increment Measurements of an Equimolar Mixture of Trichlorofluoromethane (R-11) + Dichlorodifluoromethane (R-12)
Journal of Chemical & Engineering Data, 2003Co-Authors: Gustavo A. Iglesias-silva, James C. Holste, R. C. Castro-gomez, William J. Rogers, Kenneth R HallAbstract:We have measured experimental liquid densities and enthalpy increments for an equimolar mixture of trichlorofluoromethane (R-11) + dichlorodifluoromethane (R-12). We have used a continuously weighed pycnometer for measuring the liquid densities and a thermoelectric flow calorimeter for measuring the enthalpy increments. The temperature range for all measurements is from (230 to 425) K. The experimental measurements range up to 69 MPa with the pycnometer and 6.8 MPa with the calorimeter, respectively.
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Burnett and pycnometric (p,Vm,T) measurements for natural gas mixtures
The Journal of Chemical Thermodynamics, 1997Co-Authors: Chih-an Hwang, James C. Holste, Kenneth R Hall, P.p. Simon, K. N. MarshAbstract:Accurate (p,Vm,T) measurements were performed on five natural gas mixtures using a Burnett apparatus and a high pressure, continuously-weighed pycnometer. These measurements were part of a co-operative project sponsored by the Gas Research Institute to establish an internally consistent database of experimental measurements for five representative natural gas mixtures. Burnett results are reported atT=(250, 275, 300, and 325) K for pressures to 11 MPa. Pycnometer results are reported atT=(225, 250, 275, 300, 325, and 350) K for pressures to 70 MPa.
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Densities of Carbon Dioxide + Methane Mixtures from 225 K to 350 K at Pressures up to 35 MPa
Journal of Chemical & Engineering Data, 1997Co-Authors: Chih-an Hwang, James C. Holste, Kenneth R Hall, Gustavo A. Iglesias-silva, Bruce E. Gammon, Kenneth N. MarshAbstract:This paper reports PVT measurements for five gravimetrically prepared CO2 + CH4 mixtures. A continuously-weighed, high-pressure pycnometer was used to measure densities at temperatures from 225 K to 350 K in 25 K increments and pressures to 35 MPa with one set of measurements to 69 MPa. A detailed error analysis indicates that the accuracy of the densities is better than ±0.1%.
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A Continuously Weighed Pycnometer for Measuring Fluid Properties
Journal of Chemical & Engineering Data, 1997Co-Authors: Chih-an Hwang, James C. Holste, Gustavo A. Iglesias-silva, William J. Rogers, H. B. Brugge, Horacio A. Duarte-garza, And K. R. Hall, B. E. Gammon And, K. N. MarshAbstract:This paper documents the construction details and experimental procedures for the continuously weighed pycnometer used in our laboratory to measure fluid properties such as densities, saturation pressures, phase boundaries, and isothermal compressibilities. This apparatus consists of a cell suspended from an electronic balance at all times and a variable volume bellows cell which is used to adjust the confined sample density within an isothermal enclosure. The principal advantages of this apparatus are rapid measurement and relatively high accuracy. Some experimental results are presented to illustrate capability. The accessible experimental ranges are 100−450 K up to 200 MPa; measurement accuracy is 0.1% or better.
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experimental densities of trichlorofluoromethane r 11 and chlorodifluoromethane r 22 at 270 k and up to 67 mpa
Journal of Chemical & Engineering Data, 1995Co-Authors: Gustavo A Iglesiassilva, Kenneth R Hall, James C. HolsteAbstract:The authors have used a continuously weighed pycnometer to measure compressed liquid densities of trichlorofluoromethane (R-11) and chlorodifluoromethane (R-22) at 270 K and pressures to 67 MPa. The precision of the liquid density measurements is better than {+-}0.1 kg/m{sup 3}, and the accuracy is {+-}0.08% at the 95% confidence limit. The new results agree within the combined uncertainties with published measurements in regions of overlap, and they show that existing equations of state extrapolate well to higher pressures.
S. Tamari - One of the best experts on this subject based on the ideXlab platform.
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Optimum design of the comparative gas pycnometer for determining the volume of solid particles
Geotechnical Testing Journal, 2020Co-Authors: S. Tamari, Ri López-hernándezAbstract:Little is known about the optimum design of gas Pycnometers, so that they can determine the volume of solid particles with the greatest accuracy. The purpose of this study was to investigate the optimum design of the “comparative” gas pycnometer. An error analysis was performed to derive a theoretical formula that relates the pycnometer's accuracy to the main sources of random error (sample-chamber, piston-chamber, and volume-controller volumes). The consequences of this formula in terms of optimizing the geometry and working conditions of the pycnometer are discussed. As for the “constant-volume” and “variable-volume” gas Pycnometers, which were previously investigated, it seems possible to use commercially-available components for constructing a comparative gas pycnometer that can determine the volume of solid particles with a relative standard uncertainty smaller than 0.15 %.
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optimum design of gas Pycnometers for determining the volume of solid particles
Journal of Testing and Evaluation, 2005Co-Authors: S. Tamari, A AguilarchavezAbstract:Gas pycnometry is based on Boyle-Mariotte's law. There are three kinds of gas Pycnometers reported in literature: "constant-volume", "variable-volume" and "comparative". These instruments are widely used to determine the volume -and thus the density- of granular, porous or soluble compounds (e.g., rocks, soil particles, pigments, ceramic, drugs, seeds). However, many users do not know the optimum use conditions of their gas pycnometer. This work provides a synthesis of recent studies about the optimum design of the gas Pycnometers. It seems possible to use commercially available components for constructing gas Pycnometers that can determine the volume of solid particles with a relative standard uncertainty smaller than 0.25%. Compared against other gas Pycnometers, the constant-volume pycnometer presents several practical advantages.
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Optimum design of the constant-volume gas pycnometer for determining the volume of solid particles
Measurement Science and Technology, 2004Co-Authors: S. TamariAbstract:Little is known about optimum design of gas Pycnometers, so that they can determine the volume of solid particles with the greatest accuracy. The purpose of this study was to investigate the optimum design of the 'variable-volume' gas pycnometer, because its ease of handling makes it a good candidate for widespread use. The law of propagation of uncertainty was used to derive a theoretical formula that relates the pycnometer's accuracy to the main sources of random uncertainty (gas-pressure measurements, pycnometer temperature, sample-chamber and piston-chamber volumes). The consequences of this formula in terms of optimizing the geometry and working conditions of the pycnometer are discussed. It was found that some gas Pycnometers described in the literature may not have been used under the best conditions. As for the 'constant-volume' gas pycnometer, which was considered in a previous study, it seems possible to use commercially available components for constructing a variable-volume gas pycnometer that can determine the volume of solid particles with a relative standard uncertainty smaller than 0.25%. However, an accurately calibrated pressure transducer is required for the variable-volume gas pycnometer (instead, the only requirement for the constant-volume gas pycnometer is that the transducer's response varies linearly with pressure).
Gustavo A Iglesiassilva - One of the best experts on this subject based on the ideXlab platform.
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experimental p t ρ and enthalpy increment measurements of trichlorofluoromethane r 11 x 0 83 chlorodifluoromethane r 22 1 x
Journal of Chemical & Engineering Data, 2003Co-Authors: Lâle Yurttas, Kenneth R Hall, William J. Rogers, Raul Castrogomez, And James C Holste, Gustavo A IglesiassilvaAbstract:We have measured experimental liquid densities for R-11 (x = 0.83 nominal) + R-22 (1 − x) using a continuously weighed pycnometer (for liquid densities) and a semi automated, isochoric apparatus (for measurements in the vapor and liquid regions). We calculate phase boundaries from the isochoric measurements. A thermoelectric flow calorimeter was used to measure enthalpy differences in the vapor and liquid regions. The temperature range for all measurements is (230 to 425) K. The experimental pressures range up to 69 MPa for the pycnometer, 9 MPa for the isochoric apparatus, and 6.5 MPa for the calorimeter.
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experimental densities of trichlorofluoromethane r 11 and chlorodifluoromethane r 22 at 270 k and up to 67 mpa
Journal of Chemical & Engineering Data, 1995Co-Authors: Gustavo A Iglesiassilva, Kenneth R Hall, James C. HolsteAbstract:The authors have used a continuously weighed pycnometer to measure compressed liquid densities of trichlorofluoromethane (R-11) and chlorodifluoromethane (R-22) at 270 K and pressures to 67 MPa. The precision of the liquid density measurements is better than {+-}0.1 kg/m{sup 3}, and the accuracy is {+-}0.08% at the 95% confidence limit. The new results agree within the combined uncertainties with published measurements in regions of overlap, and they show that existing equations of state extrapolate well to higher pressures.
Kenneth R Hall - One of the best experts on this subject based on the ideXlab platform.
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Experimental P−T−ρ and Enthalpy-Increment Measurements of an Equimolar Mixture of Trichlorofluoromethane (R-11) + Dichlorodifluoromethane (R-12)
Journal of Chemical & Engineering Data, 2003Co-Authors: Gustavo A. Iglesias-silva, James C. Holste, R. C. Castro-gomez, William J. Rogers, Kenneth R HallAbstract:We have measured experimental liquid densities and enthalpy increments for an equimolar mixture of trichlorofluoromethane (R-11) + dichlorodifluoromethane (R-12). We have used a continuously weighed pycnometer for measuring the liquid densities and a thermoelectric flow calorimeter for measuring the enthalpy increments. The temperature range for all measurements is from (230 to 425) K. The experimental measurements range up to 69 MPa with the pycnometer and 6.8 MPa with the calorimeter, respectively.
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experimental p t ρ and enthalpy increment measurements of trichlorofluoromethane r 11 x 0 83 chlorodifluoromethane r 22 1 x
Journal of Chemical & Engineering Data, 2003Co-Authors: Lâle Yurttas, Kenneth R Hall, William J. Rogers, Raul Castrogomez, And James C Holste, Gustavo A IglesiassilvaAbstract:We have measured experimental liquid densities for R-11 (x = 0.83 nominal) + R-22 (1 − x) using a continuously weighed pycnometer (for liquid densities) and a semi automated, isochoric apparatus (for measurements in the vapor and liquid regions). We calculate phase boundaries from the isochoric measurements. A thermoelectric flow calorimeter was used to measure enthalpy differences in the vapor and liquid regions. The temperature range for all measurements is (230 to 425) K. The experimental pressures range up to 69 MPa for the pycnometer, 9 MPa for the isochoric apparatus, and 6.5 MPa for the calorimeter.
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Experimental P−T−ρ and Enthalpy-Increment Measurements of Trichlorofluoromethane, R-11 (x = 0.83), + Chlorodifluoromethane, R-22 (1 − x)
Journal of Chemical & Engineering Data, 2003Co-Authors: Lâle Yurttas, Kenneth R Hall, R. C. Castro-gomez, William J. Rogers, And James C Holste, Gustavo A. Iglesias-silvaAbstract:We have measured experimental liquid densities for R-11 (x = 0.83 nominal) + R-22 (1 − x) using a continuously weighed pycnometer (for liquid densities) and a semi automated, isochoric apparatus (for measurements in the vapor and liquid regions). We calculate phase boundaries from the isochoric measurements. A thermoelectric flow calorimeter was used to measure enthalpy differences in the vapor and liquid regions. The temperature range for all measurements is (230 to 425) K. The experimental pressures range up to 69 MPa for the pycnometer, 9 MPa for the isochoric apparatus, and 6.5 MPa for the calorimeter.
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Burnett and pycnometric (p,Vm,T) measurements for natural gas mixtures
The Journal of Chemical Thermodynamics, 1997Co-Authors: Chih-an Hwang, James C. Holste, Kenneth R Hall, P.p. Simon, K. N. MarshAbstract:Accurate (p,Vm,T) measurements were performed on five natural gas mixtures using a Burnett apparatus and a high pressure, continuously-weighed pycnometer. These measurements were part of a co-operative project sponsored by the Gas Research Institute to establish an internally consistent database of experimental measurements for five representative natural gas mixtures. Burnett results are reported atT=(250, 275, 300, and 325) K for pressures to 11 MPa. Pycnometer results are reported atT=(225, 250, 275, 300, 325, and 350) K for pressures to 70 MPa.
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Densities of Carbon Dioxide + Methane Mixtures from 225 K to 350 K at Pressures up to 35 MPa
Journal of Chemical & Engineering Data, 1997Co-Authors: Chih-an Hwang, James C. Holste, Kenneth R Hall, Gustavo A. Iglesias-silva, Bruce E. Gammon, Kenneth N. MarshAbstract:This paper reports PVT measurements for five gravimetrically prepared CO2 + CH4 mixtures. A continuously-weighed, high-pressure pycnometer was used to measure densities at temperatures from 225 K to 350 K in 25 K increments and pressures to 35 MPa with one set of measurements to 69 MPa. A detailed error analysis indicates that the accuracy of the densities is better than ±0.1%.
H. M. Swaroop - One of the best experts on this subject based on the ideXlab platform.
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A Simplified Approach of Determining the Specific Gravity of Soil Solids
Geotechnical and Geological Engineering, 2012Co-Authors: K Prakash, A Sridharan, H. K. Thejas, H. M. SwaroopAbstract:Many computations in the field of geotechnical engineering require the use of specific gravity of soil solids. Presently, specific gravity of soil solids is determined in the laboratory by the sensitive pycnometer/density bottle method, which is characterized by many complexities and difficulties. The present technical note suggests the use of some of the measurements taken during the routine shrinkage limit test in the laboratory to compute the specific gravity of soil solids fairly accurately. It is shown through exhaustive experimental results that the values of specific gravity of soil solids obtained from the proposed method is in very close agreement with those determined from the conventional pycnometer/density bottle method.
