A new theoretical approach for estimating excess internal pressure

2006 ◽  
Vol 124 (1-3) ◽  
pp. 121-123 ◽  
Author(s):  
Ranjan Dey ◽  
A.K. Singh ◽  
J.D. Pandey
Keyword(s):  
Internal Pressure ◽  
Theoretical Approach ◽  
Excess Internal Pressure

The impact of temperature change on stress deformed state of a main pipeline surrounded by a viscous medium and affected by thrusts and dislocations of the Earth’s crust

2006 ◽  
Vol 4 ◽  
pp. 32-40
Author(s):  
M.I. Davletov ◽  
Yu.V. Kazantsev ◽  
A.G. Khakimov
Keyword(s):  
Internal Pressure ◽  
Temperature Change ◽  
Viscous Medium ◽  
Earth’S Crust ◽  
Main Pipeline ◽  
Constraint Forces ◽  
Deformed State ◽  
Earth's Crust ◽  
The Impact ◽  
Excess Internal Pressure

The present investigation concerns the movement and stress deformed state of a main pipeline with excess internal pressure surrounded by a highly viscous medium under changing temperature and also in the case of thrusts and dislocations of the Earth’s crust. Account is taken of constraint forces occurred due to excess internal pressure and temperature change.

Enthalpy of solution of tris(2,4-pentanedionato)cobalt(III) in aqueous mixed solvents of 1,4-dioxane and 2-methyl-2-propanol

1987 ◽  
Vol 65 (6) ◽  
pp. 1218-1223 ◽  
Author(s):  
Yasuki Yoshimura
Keyword(s):  
Internal Pressure ◽  
Mole Fraction ◽  
Linear Correlation ◽  
Composition Dependence ◽  
Enthalpy Of Solution ◽  
Excess Enthalpy ◽  
Mixed Solvents ◽  
Hydrophobic Hydration ◽  
System A ◽  
Excess Internal Pressure

The solubilities Xs of tris(2,4-pentanedionato)cobalt(III) (Co(acac)3) in water – 1,4-dioxane (D) and water – 2-methyl-2-propanol (TBA) mixtures were determined over the temperature range of 15–60 °C and 20–43 °C, respectively. These data were fitted to [Formula: see text] and the enthalpy of solution [Formula: see text] of Co(acac)3 was estimated by differentiating the equation. For the water–D system, a linear correlation was found between the excess enthalpy of solution [Formula: see text] of Co(acac)3 and the excess internal pressure [Formula: see text] of the mixtures. [Formula: see text] of Co(acac)3 in the water–TBA mixtures showed complicated composition dependence due to microheterogeneity in the mixtures. The enthalpy of hydrophobic hydration [Formula: see text] of Co(acac)3 in the water–D mixtures was also estimated from the solubility curves and it was found that [Formula: see text] decreased exponentially with decreasing mole fraction of water.

Intensification of foam technology by the energy of the electrohydrothermal force field. Part 1. Analysis of the features of generating internal pressure in the foam mass when electric current energy is introduced into it

2020 ◽  
pp. 56-58
Author(s):  
V. N. Sokov
Keyword(s):  
Experimental Data ◽  
Potential Energy ◽  
Force Field ◽  
Internal Pressure ◽  
Electric Current ◽  
Electronic Component ◽  
Complex Action ◽  
Temperature And Pressure ◽  
Current Energy ◽  
Excess Internal Pressure

A concept has been put forward about the potential energy inherent in the nature of the foam system to self-compact under the complex action of an electrohydrothermal force field on it. The generation of excess internal pressure in the foam system was studied analytically and experimentally. Experimental data on monitoring the dynamics of temperature and pressure were obtained using a computer and a modern electronic component base. The method inherent in the technology allows combining a number of processes in one operation: compaction of the refractory components of the mixture, removal of shrinkage moisture, stamping of any profile of a lightweight product, providing clear edges that do not require grinding and trimming of products.

Alteration of buoyancy by some Central American stream fishes, and a comparison with North American species

1976 ◽  
Vol 54 (3) ◽  
pp. 386-391 ◽  
Author(s):  
John H. Gee ◽  
Phyllis A. Gee
Keyword(s):  
Internal Pressure ◽  
Flow Regime ◽  
North American ◽  
North American Species ◽  
Central American ◽  
Water Current ◽  
Stream Fishes ◽  
Swim Bladder ◽  
The North ◽  
Excess Internal Pressure

Of 23 species (nine families) of Central American fishes examined, nine (eight physostomes, one physoclist) did not reduce buoyancy by decreasing swim-bladder volume when current was encountered. The remainder (six physostomes, eight physoclists) decreased buoyancy, usually within 24–48 h, but three of these species (one physostome) were unable to maintain a reduced buoyancy for as long as 72 h once the minimum was achieved. All species have an excess internal pressure of swim-bladder gas. All of the North American species that have been studied do show a buoyancy alteration in response to changes in water current and adjust to a greater extent, although rates of adjustment appear similar to those of Central American fishes. Differences in flow regime between North and Central American streams are described and may partially account for these differences in reaction to water current.

Adjustment of Buoyancy and Excess Internal Pressure of Swimbladder Gases in Some North American Freshwater Fishes

1974 ◽  
Vol 31 (6) ◽  
pp. 1139-1141 ◽  
Author(s):  
John H. Gee ◽  
Kazimierz Machniak ◽  
Sandra M. Chalanchuk
Keyword(s):  
Internal Pressure ◽  
North American ◽  
Freshwater Fishes ◽  
Water Velocity ◽  
North American Freshwater ◽  
Excess Internal Pressure

All 12 species of physostomes and 8 species of physoclists altered their buoyancy in response to a change in water velocity. All species showed excess internal pressure of swimbladder gases.

The Physical Properties of the Swimbladder in Intact Cypriniformes

1959 ◽  
Vol 36 (2) ◽  
pp. 315-332 ◽  
Author(s):  
R. MCN. ALEXANDER
Keyword(s):  
Physical Properties ◽  
Internal Pressure ◽  
Elastic Properties ◽  
Extreme Case ◽  
Relative Sensitivity ◽  
Rate Of Change ◽  
Surrounding Water ◽  
Small Depth ◽  
Mean Pressure ◽  
Excess Internal Pressure

1. A method is described whereby certain physical properties of the swimbladder have been determined in intact, unoperated Cypriniformes. These properties are volume, excess internal pressure, extensibility, and relative sensitivity (an index of the rate of change of volume with depth). 2. The mean volume of the swimbladder varies in the twelve species examined from 5.8 to 9.9 ml./100 g. body weight. 3. In most Cyprinidae the swimbladder gases are maintained at a mean pressure 2-3 cm. Hg above that of the surrounding water at the depth to which the fish is adapted. Higher pressures occur in a few species, most notably the bream (10.8 cm. Hg). A much lower pressure is found in Amiurus. An excess internal pressure is probably necessary to provide a taut swimbladder wall to operate Weberian ossicles. 4. The swimbladder wall has non-linear elastic properties such that as the excess pressure in the swimbladder rises the extensibility of its wall falls. The swimbladder also shows slow-elastic properties. The significance of these properties is discussed. 5. Excess internal pressure and low extensibility combine to limit the rate at which the volume of the swimbladder, and so the buoyancy of the fish, changes with depth. For small depth changes the swimbladder of the bream (an extreme case) changes its volume only one-quarter as much as would a free air-bubble.

Pressure and temperature dependence of the excess thermodynamic properties of binary dimethyl carbonate + n-octane mixtures

2003 ◽  
Vol 81 (7) ◽  
pp. 840-849 ◽  
Author(s):  
Luis Lugo ◽  
María JP Comuñas ◽  
Enriqueta R López ◽  
Josefa García ◽  
Josefa Fernández
Keyword(s):  
Thermodynamic Properties ◽  
Internal Pressure ◽  
Atmospheric Pressure ◽  
Dimethyl Carbonate ◽  
Excess Molar Enthalpies ◽  
Excess Thermodynamic Properties ◽  
Gibbs Energies ◽  
Isobaric Expansivity ◽  
Temperature And Pressure ◽  
Excess Internal Pressure

In this work we report several excess thermodynamic properties for the dimethyl carbonate + n-octane system in an effort to better understand their behavior over wide temperature and pressure ranges. From previous experimental pVTx data for this system, the changes in the excess molar Gibbs energies, in the excess molar entropies, and in the excess molar enthalpies due to pressure have been determined over a wide temperature range and for pressures up to 25 MPa. A correlation of the excess volume as a function of pressure was used for each composition and temperature, together with a new, recently proposed equation for the excess molar volume as a function of temperature, pressure, and composition. Excess molar enthalpies and excess molar Gibbs energies at 298.15 K and for pressures up to 25 MPa were calculated using literature data at atmospheric pressure. Furthermore, the excess isothermal compressibility, the excess isobaric expansivity, and the excess internal pressure were calculated. The expression for the internal pressure of an ideal mixture suggested recently by Marczak has been used.Key words: excess thermodynamic properties, dimethyl carbonate, n-octane, high pressure.

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