scholarly journals Experimental Determination of CO2 Diffusion Coefficient in a Brine-Saturated Core Simulating Reservoir Condition

Energies ◽  
2021 ◽  
Vol 14 (3) ◽  
pp. 540
Author(s):  
Zerong Li ◽  
Lei Yuan ◽  
Guodong Sun ◽  
Junchen Lv ◽  
Yi Zhang
Keyword(s):  
Diffusion Coefficient ◽  
Co2 Storage ◽  
Co2 Diffusion ◽  
Nacl Concentration ◽  
Reservoir Conditions ◽  
Temperature And Pressure ◽  
The Relationship ◽  
Crucial Part

CO2 diffusion coefficient plays a crucial part in saline aquifers for the CO2 storage and the safety of long-term sequestration. Therefore, it is particularly important to measure the diffusion coefficient accurately. As far as we know, there are currently no CO2 brine diffusion data in real cores under reservoir temperature and pressure conditions. In this paper, a study on the CO2 diffusion coefficient diffused in a brine-saturated Berea core along the radial direction was conducted at temperatures of 313.15 K to 373.15 K and pressures of 8 MPa to 30 MPa. On account of the experimental results, the effect of permeability, NaCl concentration, temperature and pressure on the CO2 diffusivity is analyzed. The results in this study indicate that the diffusion coefficient increases with increasing permeability, pressure and temperature and decreases with increasing NaCl concentration. However, the relationship between pressure and the diffusion coefficient is not linear. As the pressure gradually increases, the effect of pressure will become weak. In addition, an empirical correlation of the relationship between temperature–pressure and the CO2 diffusion coefficient could be obtained based on the experimental data. The data in this paper fill the blank on the study of the CO2 diffusivity in brine under reservoir conditions, which has positive significance for the study of supercritical CO2 diffusion in a brine-saturated core.

Carbon Black. I—A Study of Its Volatile Constituents

1928 ◽  
Vol 1 (3) ◽  
pp. 485-497 ◽  
Author(s):  
C. R. Johnson
Keyword(s):  
Carbon Black ◽  
Volatile Matter ◽  
Original Sample ◽  
Missing Information ◽  
Volatile Constituents ◽  
Vulcanized Rubber ◽  
Rates Of Evolution ◽  
Temperature And Pressure ◽  
The Relationship

Abstract The rates of evolution of gas from carbon black with variation of time, temperature, and pressure have been determined. Complete analyses have been made of five types of carbon black, which involve an organic combustion of the original sample, an organic combustion of the sample after the gases have been removed, a determination of the loss in weight represented by the gases removed, analyses of the gases removed, and finally a complete accounting, or balance, of the carbon in the steps considered. In an attempt to supply some missing information not revealed by the foregoing, some special gas analyses under varying conditions were made. The relationship between the amount and composition of volatile matter evolved from carbon blacks and the properties imparted to vulcanized rubber when compounded with these blacks has been studied.

scholarly journals The Effect of Oil Properties on the Supercritical CO2 Diffusion Coefficient under Tight Reservoir Conditions

Energies ◽  
2018 ◽  
Vol 11 (6) ◽  
pp. 1495 ◽  
Author(s):  
Chao Zhang ◽  
Chenyu Qiao ◽  
Songyan Li ◽  
Zhaomin Li
Keyword(s):  
Diffusion Coefficient ◽  
Supercritical Co2 ◽  
Co2 Diffusion ◽  
Tight Reservoir ◽  
Reservoir Conditions

scholarly journals GENERAL ANALYSIS OF STRESS AND DEFORMATION OF PARTS MOVING WITH HIGH VELOCITY IN A LIQUID OR GAS (REVIEW ARTICLE)

2021 ◽  
pp. 71-76
Author(s):  
Mykola Prokopenko
Keyword(s):  
Working Conditions ◽  
Thermal Fatigue ◽  
Uniaxial Stress ◽  
Material Strength ◽  
High Speeds ◽  
Analytical Review ◽  
Stress And Deformation ◽  
The Relationship

The article provides an analytical review and analysis of stresses and deformations of parts moving at high speeds in a liquid or gas. The working conditions of materials and parts of turbines (blades, rotor and casing) operating at high temperatures and loads are analyzed. The main ways of solving the problem of ensuring the strength of such parts are presented. The main ways to solve the problem of reliability of parts or the product as a whole are given: mathematical modeling (calculated determination of strength, durability and reliability); physical modeling (model testing); testing of full-scale products in reproducible real or operational conditions.It is impossible to speak about the strength of a part only from the calculation of deformations and stresses, even taking into account their change over time, so it is necessary to have strength criteria that establish the relationship between the strength parameters. It is emphasized that in the general case, the criterion of strength should answer the question: will the part collapse or not with the known laws of change in time of stresses, strains and temperatures It is shown that the considered standard characteristics of creep and long-term strength can be directly used in calculations only for those parts in which the uniaxial stress state at constant stresses and temperature is realized, when the working conditions of the material fully meet the test conditions of materials.An analytical view of deformation diagrams is considered as the main means of carrying out practical calculations of material strength. It is shown that in order to determine the stresses and strains in parts that move at high speeds in a liquid or gas, it is necessary to take into account the model of parts exploitation, the processes of creep and thermal fatigue of the material, and the unsteadiness of load processes. Keywords: stresses and deformations of turbine parts; deformation diagram; operating model of turbine parts; creep and thermal fatigue; nonstationarity of loading processes  

Rubidium Sulfate Flame Detector: Effect of Design of Alkali Source and Anode on Sensitivity and Stability

1969 ◽  
Vol 52 (3) ◽  
pp. 533-541
Author(s):  
Hiroko K DeLoach ◽  
D D Hemphill
Keyword(s):  
Detection System ◽  
Physical Stability ◽  
Optimum Conditions ◽  
Flame Detector ◽  
Short And Long Term ◽  
Rubidium Sulfate ◽  
Relationship Of ◽  
The Relationship

Abstract An improved alkali-flame detector using pure rubidium sulfate and an anode of new design were optimized for the quantitative determination of organophosphate pesticides. The performance of this detection system was evaluated for response to organophosphate standards, noise level, fluctuation of baseline, short- and long-term reproducibility at low pesticides levels, conditioning time of instrument, life and physical stability of alkali source, and required frequency of detector cleaning. Under optimum conditions the detector was sensitive to 1 pg pesticide standard. To define the parameters of the alkali flame detector, studies were made of different designs of the alkali source which influence flame configuration and the relationship of the position and shape of the anode to the flame. The most important parameter appears to be the method of introducing alkali vapor.

Physics and Metrology

2017 ◽  
Author(s):  
Kathryn M. Olesko
Keyword(s):  
Electrical Resistance ◽  
Moral Values ◽  
Thomas Kuhn ◽  
History Of ◽  
Historical Issues ◽  
The Relationship

This article traces the history of the relationship between physics and metrology, or physical metrology. It first examines how metrology became a part of the concerns of historians of science, and particularly physics, citing the work of Alexandre Koyré, Thomas Kuhn, and Witold Kula. It then describes various approaches to physics and metrology, focusing on the construction of a standard of length based on the seconds pendulum and the determination of the unit of electrical resistance. It also discusses broader historical issues in physics and metrology, including labour practices in physics, physics pedagogy, long-term processes of modernity (bureaucratization, industrialization, and the construction of empires), and the moral and ethical connotations of standards of measure. It shows that moral values became intertwined with metrology, especially in the British context.

scholarly journals 2.2.3 The Long Term Population of Interplanetary Micrometeoroids

1976 ◽  
Vol 31 ◽  
pp. 232-232
Author(s):  
G. Poupeau ◽  
R.M. Walker ◽  
E. Zinner ◽  
D. Morrison
Keyword(s):  
Solar Flare ◽  
Free Space ◽  
Lunar Regolith ◽  
Lunar Soil ◽  
The Past ◽  
Ion Probe ◽  
Space Data ◽  
The Relationship

Three problems will be discussed: A) The relationship between mlcro-meteoroids and solar flare particles averaged over the recent geologic past (~1 my); B) the past record of this relationship as measured in lunar soils and lunar and meteoritic breccias; C) the determination of the time at which different extraterrestrial samples were exposed to free space. Data bearing on these points obtained from studies of special lunar rocks and from measurements on individual crystals removed from lunar cores will be presented. Progress in using ion-probe mass spectrometry to link measurements of micro-impact craters with the past properties of the solar wind will also be discussed. Comparing microcraters and solar flare tracks in individual crystals from lunar cores, we find no evidence of any extraordinary variations for a time span covering an interval of ~109 yrs. Crystals 100µ to 400µ in size in mature lunar soil samples appear to have been exposed 3 to free space at the top of the lunar regolith for times from 103 to 104 yrs.

scholarly journals The Relationship between Hope and Perceived Stress in Teacher Candidates

2019 ◽  
Vol 8 (2) ◽  
pp. 1
Author(s):  
Serdar Sucan
Keyword(s):  
Perceived Stress ◽  
Personnel Selection ◽  
Teacher Candidates ◽  
Negative Effects ◽  
Positive Effects ◽  
Preparatory Course ◽  
High Level ◽  
The Relationship

The long-term and uncontrollable stress of KPSS (Personnel Selection Examination) candidates disrupts their psychology, weakens thinking and decision-making, and thus decreases academic achievement. The aim of this study is; It is the determination of the relationship between the level of hope and perceived stress of teacher candidates prepared for KPSS.A total of 382 teacher candidates participated in a special KPSS preparatory course in Kayseri. Candidate teachers who graduated from different departments and universities are between the ages of 21-25 in 41.6%. When we look at socio-demographic characteristics; 68.4% male; 59.9% single and 51.5% were at medium income level. Perceived Stress Scale (PSS-10) and Adult Hope Scale (AHS) were administered to the participants. The mean AHS score of the teacher candidates was 27.73±1.92. This shows the high level of hope of the participants. Perceived Stress level was found to be medium at 53.6%. As a result of the analysis, a significant a negative correlation was found between level of hope and perceived stress (p <0.01). According to regression analysis, level of hope in teacher candidates showed a statistically significant positive effect on perceived stress (p <0.01).As a result, negative relationships were found between hope and perceived stress. It is thought that highly hopeful people perceive stress lower and life satisfaction increases. Therefore, in order to increase the level of hope and to reduce the negative effects of stress, educators should support KPSS candidates. Programs related to the high level of hope to be implemented in schools may have positive effects on individuals' low stress and examinations.

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