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Temperature-independent

Calculated with temperature-independent UNIQUAC parameters. [Pg.47]

Figure 2 shows similar results for ethanol(1)-n-hexane(2) at 1 atm. The liquid-phase enthalpy of mixing was again estimated from UNIQUAC using temperature-independent parameters. [Pg.90]

CHECK CONTROL IKEY). IF -I OR 0 CALCULATE TEMPERATURE INDEPENDENT PARAMETERS. [Pg.263]

If the variation of density and hence molar volume with temperature is small, it follows from Eqs. Ill-10 and III-8 that E will be nearly temperature-independent. In fact, Eq. Ill-11 with n = 1 may be written in the form... [Pg.51]

For hard spheres, the coefficients are independent of temperature because the Mayer/-fiinctions, in tenns of which they can be expressed, are temperature independent. The calculation of the leading temiy fy) is simple, but the detennination of the remaining tenns increases in complexify for larger n. Recalling that the Mayer /-fiinction for hard spheres of diameter a is -1 when r < a, and zero otherwise, it follows thaty/r, 7) is zero for r > 2a. For r < 2a, it is just the overlap volume of two spheres of radii 2a and a sunple calculation shows tliat... [Pg.469]

The two primary causes of shielding by electrons are diamagnetism and temperature-independent paramagnetism (TIP). Diamagnetism arises from the slight unpairing of electron orbits under the influence of the magnetic field. This always occurs so as to oppose the field and was first analysed by Lamb [7]. A simplified version of his fomuila. [Pg.1445]

These values are practically temperature independant, and they are very close to those found for the Apiezon L column. Comparison with the values of a series of alkybenzenes shows that the 5-position of thiazole possesses behavior analogous to that of a benzenic position in gas-liquid chromatography. [Pg.362]

Molality is used in thermodynamic calculations where a temperature independent unit of concentration is needed. Molarity, formality and normality are based on the volume of solution in which the solute is dissolved. Since density is a temperature dependent property a solution s volume, and thus its molar, formal and normal concentrations, will change as a function of its temperature. By using the solvent s mass in place of its volume, the resulting concentration becomes independent of temperature. [Pg.18]

Friction Materials. PhenoHc friction materials are made from mol ding compounds developed to meet the extraordinary demands required by friction elements in the transportation industries. Friction materials are used for brake linings, clutch facings, and transmission bands. A moderately high coefficient of friction, which is temperature-independent, is needed. In addition, the material must be high in strength, low in wear and abrasion, and resistant to moisture and hydrauHc fluids. [Pg.305]

When there are two or mote variables, they might interact with one another, ie, the effect of one variable upon the response depends on the value of the other variable. Figure 1 shows a situation where two noninteracting variables, preparation type and temperature, independently affect time to mpture, ie, the effect of temperature on time to mpture is the same for both preparation types. In contrast. Figure 2 shows two examples of interactions between preparation and temperature. [Pg.519]

Parachor is the name (199) of a temperature-independent parameter to be used in calculating physical properties. Parachor is a function of Hquid density, vapor density, and surface tension, and can be estimated from stmctural information. Critical constants for about 100 organic substances have been correlated to a set of equations involving parachors and molar refraction (200). [Pg.253]

The temperature-independent parachor [P] may be calculated by the additive scheme proposed by Quale.The atomic group contributions for this method, with contributions for silicon, boron, and aluminum from Myers,are shown in Table 2-402. At low pressures, where Pi. pc, the vapor density term may be neglected. Errors using Eq. (2-168) are normally less than 5 to 10 percent. [Pg.416]

The origin of the isotope effect is the dependence of coq and co on the reacting particle mass. Classically, this dependence comes about only via the prefactor coq [see (2.14)], and the ratio of the rate constants of transfer of isotopes with masses mj and m2 m2 > mj) is temperature-independent and equal to... [Pg.31]

A eomputer program, PROG2, was developed to fit the data by least squares of a polynomial regression analysis. The data of temperature (independent variable) versus heat eapaeity (dependent variable) were inputted in the program for an equation to an nth degree... [Pg.91]

CNTs are purified by oxidizing the crude ones as prepared. During the oxidation process, the nanoparticles are removed gradually and eventually only open CNTs remain [9]. An intrinsic CESR was observed from these purified COTs [12]. The temperature dependencies of susceptibility, linewidth and g-value of the CESR are shown in Fig. 2 (open circle). We find a temperature independent spin susceptibility (Pauli) = 4.3 x 10 emu/g. [Pg.78]

Typical magnetoconductance data for the individual MWCNT are shown in Fig. 4. At low temperature, reproducible aperiodic fluctuations appear in the magnetoconduclance. The positions of the peaks and the valleys with respect to magnetic field are temperature independent. In Fig. 5, we present the temperature dependence of the peak-to-peak amplitude of the conductance fluctuations for three selected peaks (see Fig. 4) as well as the rms amplitude of the fluctuations, rms[AG]. It may be seen that the fiuctuations have constant amplitudes at low temperature, which decrease slowly with increasing temperature following a weak power law at higher temperature. The turnover in the temperature dependence of the conductance fluctuations occurs at a critical temperature Tc = 0.3 K which, in contrast to the values discussed above, is independent of the magnetic field. This behaviour was found to be consistent with a quantum transport effect of universal character, the universal conductance fluctuations (UCF) [25,26]. UCFs were previously observed in mesoscopic weakly disordered... [Pg.117]


See other pages where Temperature-independent is mentioned: [Pg.45]    [Pg.90]    [Pg.93]    [Pg.131]    [Pg.262]    [Pg.264]    [Pg.304]    [Pg.51]    [Pg.626]    [Pg.658]    [Pg.509]    [Pg.628]    [Pg.629]    [Pg.632]    [Pg.324]    [Pg.443]    [Pg.358]    [Pg.319]    [Pg.370]    [Pg.572]    [Pg.353]    [Pg.237]    [Pg.4]    [Pg.104]    [Pg.113]    [Pg.45]    [Pg.125]    [Pg.125]    [Pg.84]    [Pg.93]    [Pg.111]    [Pg.116]    [Pg.101]    [Pg.368]    [Pg.188]   


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