Dependence relation

Temperature dependence (related to the temperature dependence of the conformational structure and the morphology of polymers) of the radiation effect on various fluoropolymers e.g., poly (tetrafluoroethylene-co-hexafluoropropylene), poly(tetrafluoroethylene-co-perfluoroalkylvinylether), and poly(tetrafluoroethylene-co-ethylene) copolymers has been reported by Tabata [419]. Hill et al. [420] have investigated the effect of environment and temperature on the radiolysis of FEP. While the irradiation is carried out at temperatures above the glass transition temperature of FEP, cross-linking reactions predominate over chain scission or degradation. Forsythe et al. [421]... 

Staudinger, J., Roberts, P.V. (2001) A critical compilation of Henry s law constant temperature dependence relations for organic compounds in dilute aqueous solutions. Chemosphere 44, 561-576. 

PCBs accumulated in dose-dependent relation. Treated groups had significantly lower whole-body, liver, and ovary weight and increased hepatic EROD... 

In principle, the three isotope method may be widely applied to new isotope systems such as Mg, Ca, Cr, Fe, Zn, Se, and Mo. Unlike isotopic analysis of purified oxygen, however, isotopic analysis of metals that have been separated from complex matrices commonly involves measurement of several isotopic ratios to monitor potential isobars, evaluate the internal consistency of the data through comparison with mass-dependent fractionation relations (e.g., Eqn. 8 above), or use in double-spike corrections for instrumental mass bias (Chapter 4 Albarede and Beard 2004). For experimental data that reflect partial isotopic exchange, their isotopic compositions will not lie along a mass-dependent fractionation line, but will instead lie along a line at high angle to a mass-dependent relation (Fig. 10), which will limit the use of multiple isotopic ratios for isobar corrections, data quality checks, and double-spike corrections. 

To separate the effects of static and dynamic disorder, and to obtain an assessment of the height of the potential barrier that is involved in a particular mean-square displacement (here abbreviated (x )), it is necessary to find a parameter whose variation is sensitive to these quantities. Temperature is the obvious choice. A static disorder will be temperature independent, whereas a dynamic disorder will have a temperature dependence related to the shape of the potential well in which the atom moves, and to the height of any barriers it must cross (Frauenfelder et ai, 1979). Simple harmonic thermal vibration decreases linearly with temperature until the Debye temperature Td below To the mean-square displacement due to vibration is temperature independent and has a value characteristic of the zero-point vibrational (x ). The high-temperature portion of a curve of (x ) vs T will therefore extrapolate smoothly to 0 at T = 0 K if the sole or dominant contribution to the measured (x ) is simple harmonic vibration ((x )y). In such a plot the low-temperature limb is expected to have values of (x ) equal to about 0.01 A (Willis and Pryor, 1975). Departures from this behavior indicate more complex motion or static disorder. 

The geometry was fully optimized in all the nuclear conformations. The optimized coordinates [5] have been refined with the reduction of the quota imposed to the gradients in the optimization process. The dependence relation (eq. 7) of the internal coordinates on the vibrational coordinate determined with MP2/AUG-cc-pVTZ are the following ... 

NT302 Meisel, P., C. Schwahn, D. Gesch, O. N P312 Bernhardt, U. John, and T. Kocher. Dose-dependent relation of smoking and the interleukin-1 gene polymorphism in periodontal tissue. J Perio-dontol 2004 75(2) 236-242. 

The set of all direct mechanisms in a system contains within it a basis for the vector space of all mechanisms. In general, there are more direct mechanisms than basis elements, which means that there can exist linear dependence relations among direct mechanisms but, even so, they differ chemically. That is, a direct mechanism with a given step omitted cannot be considered to result from a combination of two other mechanisms in which that step is assumed to occur. In the latter case the net velocity of zero for that step would result from a cancellation of equal and opposite net velocities rather than from the complete absence of the step. The set of all direct mechanisms (unlike a basis) is a uniquely defined attribute of a chemical system. In fact what we have called a direct mechanism is what is usually called a mechanism in chemical literature, even though the definition may be implicit. 

The classical (or semiclassical) equation for the rate constant of e.t. in the Marcus-Hush theory is fundamentally an Arrhenius-Eyring transition state equation, which leads to two quite different temperature effects. The preexponential factor implies only the usual square-root dependence related to the activation entropy so that the major temperature effect resides in the exponential term. The quadratic relationship of the activation energy and the reaction free energy then leads to the prediction that the influence of the temperature on the rate constant should go through a minimum when AG is zero, and then should increase as AG° becomes either more negative, or more positive (Fig. 12). In a quantitative formulation, the derivative dk/dT is expected to follow a bell-shaped function [83]. 

These findings of impaired hippocampal activation during memory retrieval in chronic patients with schizophrenia have now been complemented by a study of hippocampal-based encoding of memory in first-episode psychosis (FEP) patients (Achim et al., 2007). While some hippocampal functions remained intact, the FEP patients demonstrated a selective deficit to engage hippocampal-dependent relational binding when presented with arbitrary stimulus pairs, resulting in poorer subsequent recognition performance. 

Upon UV irradiation, fulgide 35 is converted to compound 36, with a quantum yield of 0.20 in toluene at room temperature. It is wavelength independent between 313 and 366 nm. In contrast, the quantum yield of photobleaching of compound 36 was found to be temperature and wavelength dependent. The linear-dependent relation in toluene at 21°C is shown in Eq. 4.1. 

All the operators P2, and L are gauge dependent, relating to the position of atom A... 

The association constants Kc of 1.1 electrolytes calculated with the help of free ion and ion-pur concentrations, c° and c/p, deduced from the spectra show the usual concentration dependence relating Kc to the thermodynamic equilibrium constant Ka... 

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