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Temperature relationship with energy

Thus, the conducted research showed that absolute reaction rate theory is not applicable to the explanation of the composition s viscosity-temperature relationship. It was found that the fi e volume theory allows us to describe the viscosity-temperature relationship with satisfactory accuracy within the studied temperature range from nunus -20 to 50 C. Parts of the fi ee fluctuation volume and viscous flow activation energy values determining fluids properties were calculated. [Pg.667]

The rotating spindle viscosity followed the normal Arrhenius temperature relationship with a slightly higher activation energy for the maleated and sulfonated asphalts (without added metal oxide). The viscosity-temperature relationships of two of the modified asphalts are compared with that of the unmodified asphalt (see Figure 8). [Pg.176]

It is thus seen that heat capacity at constant volume is the rate of change of internal energy with temperature, while heat capacity at constant pressure is the rate of change of enthalpy with temperature. Like internal energy, enthalpy and heat capacity are also extensive properties. The heat capacity values of substances are usually expressed per unit mass or mole. For instance, the specific heat which is the heat capacity per gram of the substance or the molar heat, which is the heat capacity per mole of the substance, are generally considered. The heat capacity of a substance increases with increase in temperature. This variation is usually represented by an empirical relationship such as... [Pg.231]

A similar relationship was found for the N0 and N02 sensor cells. The background current observed over the same temperature range with zero air (air containing none of the test gases) remained essentially constant 0 2 jua. A least square fit of the temperature data for CO in air (0 to 1000 ppm), N0 in air (0 to 200 ppm) and N02 (0 to 14 ppm) yielded activation energies as follows -... [Pg.564]

The columns of cells below row 16 contain the values of the dependent variables at the node points. They will all be iterated until a final solution is achieved. The formula in each cell represents an appropriate form of the difference equations. Each column represents an equation. Column B represents the continuity equation, column C represents the radial momentum equation, column D represents the circumferential momentum equation, and column E represents the thermal energy equation. Column F represents the perfect-gas equation of state, from which the nondimensional density is evaluated. The difference equations involve interactions within a column and between columns. Within a column the finite-difference formulas involve the relationships with nearest-neighbor cells. For example, the temperature in some cell j depends on the temperatures in cells j — 1 and j + 1, that is, the cells one row above and one row below the target cell. Also, because the system is coupled, there is interaction with other columns. For example, the density, column F, appears in all other equations. The axial velocity, column B, also appears in all other equations. [Pg.803]

A certain amount of energy will be required to raise the molecules to a level of kinetic energy where they will escape. In the special case of a liquid passing to the vapor state, the energy put into the system to cause volatilization is the latent heat of vaporization. The property is characteristic for a given chemical and may vary with temperature. The temperature relationship of the latent heat of vaporization may be calculated by the Clausius-Clapyeron equation. [Pg.81]

Electromotive force measurements of the cell Pt, H2 HBr(m), X% alcohol, Y% water AgBr-Ag were made at 25°, 35°, and 45°C in the following solvent systems (1) water, (2) water-ethanol (30%, 60%, 90%, 99% ethanol), (3) anhydrous ethanol, (4) water-tert-butanol (30%, 60%, 91% and 99% tert-butanol), and (5) anhydrous tert-butanol. Calculations of standard cell potential were made using the Debye-Huckel theory as extended by Gronwall, LaMer, and Sandved. Gibbs free energy, enthalpy, entropy changes, and mean ionic activity coefficients were calculated for each solvent mixture and temperature. Relationships of the stand-ard potentials and thermodynamic functons with respect to solvent compositions in the two mixed-solvent systems and the pure solvents were discussed. [Pg.354]

Pai et al. (1983) measured hole mobilities of a series of bis(diethylamino)-substituted triphenylmethane derivatives doped into a PC and poly(styrene) (PS). The mobilities varied by four orders of magnitude, while the field dependencies varied from linear to quadratic. In all materials, the field dependencies decreased with increasing temperature. The temperature dependencies were described by an Arrhenius relationship with activation energies that decrease with increasing field. Pai et al. described the transport process as a field-driven chain of oxidation-reduction reactions in which the rate of electron transfer is controlled by the molecular substituents of the hopping sites. [Pg.356]

Borsenberger et al. (1978) measured hole mobilities of TPA doped PC over the same concentration range reported by Pfister. The temperature dependencies were described by an Arrhenius relationship with a high-field activation energy of 0.30 eV. The activation energy was independent of the TPA concentration and weakly field dependent. The concentration dependence gave a wave-function decay constant of 1.8 A. [Pg.402]

Troup et al. (1980) measured hole mobilities of TTA doped PC. The concentration dependence was described by the lattice gas model with a wavefunction decay constant of 1.1 A. The temperature dependence was described by an Arrhenius relationship with an activation energy of 0.35 eV at 1.0 x 105 V/cm. [Pg.405]

Ulanski et al. (1990) described hole mobilities of poly(paracyclophane) (PDE) and PDE doped with 4% tetracyanoethylene (TCNE). The field dependencies were described as log i < E. The temperature dependencies were described by an Arrhenius relationship with a field-dependent activation energy. For PDE, the zero-field energy was 0.80 eV. The incorporation of TCNE resulted in an increase in mobility of approximately an order of magnitude. The authors suggested that this is caused by a decrease in the plane-to-plane distance in a cyclophane unit due to complexing with TCNE. [Pg.478]

Equation (2-80) expresses the retention of an ionizable basic analyte as a function of pH and three different constants ionization constant adsorption constant of ionic form of the analyte (7 bh+) and adsorption constant of the neutral form of the analyte (T b)- These three constants describe three different equilibrium processes, and they have their own relationships with the system temperature and Gibbs free energy with respect to the particular analyte form. [Pg.61]


See other pages where Temperature relationship with energy is mentioned: [Pg.518]    [Pg.253]    [Pg.15]    [Pg.470]    [Pg.419]    [Pg.591]    [Pg.167]    [Pg.457]    [Pg.114]    [Pg.128]    [Pg.173]    [Pg.142]    [Pg.296]    [Pg.518]    [Pg.26]    [Pg.404]    [Pg.317]    [Pg.320]    [Pg.340]    [Pg.167]    [Pg.489]    [Pg.671]    [Pg.153]    [Pg.311]    [Pg.298]    [Pg.161]    [Pg.293]    [Pg.191]    [Pg.393]    [Pg.416]    [Pg.422]    [Pg.447]    [Pg.465]    [Pg.551]    [Pg.573]    [Pg.393]    [Pg.179]    [Pg.31]    [Pg.75]   
See also in sourсe #XX -- [ Pg.7 , Pg.60 , Pg.87 , Pg.464 ]




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