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Correlation between initial

I. F. Small et al. 1986), and in our experience the same may hold true for some young patients with schizophrenia. However, confounding variables such as age and gender have not been addressed in these studies. In patients with major depressive disorder, we found no relation between seizure threshold and unipolar versus bipolar or psychotic versus nonpsychotic subtypes. Similarly, Coffey et al. (1995a) found no correlation between initial seizure threshold and severity of depressive illness or the unipolar-bipolar distinction. Finally, we found that history of ECT did not predict seizure threshold (Krueger et al. 1993). [Pg.170]

Correlation between initial concentrations of NaDDC NiS04 Urea Sr (%)... [Pg.653]

The photodissociation of van der Waals complexes may be considered as prototype of more complex processes occurring during the photofragmentation of a polyatomic molecule ABC-l-/iv- (ABC) - AB + C. As in the previous case, we expect a close correlation between initially prepared state of the parent molecule and the energy distribution in AB and C fragments. However, after the breakdown of the B—C, the frag-... [Pg.372]

Further elucidation of the reactivity of Pd colloids was reported by Bradley and Blackmond [13]. These authors prepared a series of well defined homopolymer-stabilised Pd colloids, varying the particle size, and used them in the Heck reaction between 4-bromobenzaldehyde and butyl acrylate. Interestingly, the authors found a correlation between initial rate and particle size the initial rate increases with decreasing particle size. No correlation was reported regarding the palladium specific surface area. Whereas the precise morphology of the Pd particles could not be defined, the authors found that they were quite equidimensional, allowing a representation as regular polyhedra to apply surface defect site statistics to char-... [Pg.306]

The direct correlation between initial structure of polymer and kinetics of oxygen absorption is consequent from our scheme (Shibryaeva L.S.and al.,2003 2006 2010.)... [Pg.83]

Figure 1. Correlation between initial conqjliance (A, top), initial tensile strength (B, middle), and the ratio (A/B) and the reciprocal spin-lattice relaxation time for jfresh silk fabrics. K. M. and H are data points for the reciprocal spin-lattice relaxation times of the silk fabrics in Chusanji ten jle, placed on the least-square straight lines. Figure 1. Correlation between initial conqjliance (A, top), initial tensile strength (B, middle), and the ratio (A/B) and the reciprocal spin-lattice relaxation time for jfresh silk fabrics. K. M. and H are data points for the reciprocal spin-lattice relaxation times of the silk fabrics in Chusanji ten jle, placed on the least-square straight lines.
Associated with the development of the Master Curve concept, which is discussed in Section 10.3.4, studies have concluded that it is possible to develop correlations describing a relationship between crack initiation and arrest toughness (Wallin, 2001). These studies have focused on clarifying which elements of the Master Curve approach should be modified for assessing crack arrest and finding possible correlations between initiation and arrest parameters. Due to different mechanisms and differences in factors controlling fracture initiation and arrest events (e.g. the local properties are crucial for crack initiation, but not so critical for crack arrest), the weakest link theory applied in the Master Curve approach is not directly suitable for crack arrest. [Pg.305]

FIfl. 6 Correlations between initial modulus and x-ray orientation angle for an HBA/HNA TLCP. Filled symbols represent samples having orientation differences developed either in the die (by varying die L/D) or in the spinline (by varying draw ratio) at various extrusion temperatures die 290°C ( ), spinline 290°C ( ), and die 300°C (A)- Data of Kenig [41] (O) and Calundann et al. [43] ( ) are plotted for comparison. (From Ref. 67 with permission.)... [Pg.324]

Stach H, Fiedler K, Janchen J (1993) Correlation between initial heats of adsorption and structural parameters of molecular sieves with different chemical composition—a calorimetric smdy. Pure Appl Chem 65(10) 2193-2200... [Pg.42]

These number fluctuations, i.e. the A fy ) tenn, will constantly tend to be eliminated by diffusion. On the other hand, because of the correlation between s and i, initial inliomogeneities in their spatial densities lead to the... [Pg.2829]

Breslow studied the dimerisation of cyclopentadiene and the reaction between substituted maleimides and 9-(hydroxymethyl)anthracene in alcohol-water mixtures. He successfully correlated the rate constant with the solubility of the starting materials for each Diels-Alder reaction. From these relations he estimated the change in solvent accessible surface between initial state and activated complex " . Again, Breslow completely neglects hydrogen bonding interactions, but since he only studied alcohol-water mixtures, the enforced hydrophobic interactions will dominate the behaviour. Recently, also Diels-Alder reactions in dilute salt solutions in aqueous ethanol have been studied and minor rate increases have been observed Lubineau has demonstrated that addition of sugars can induce an extra acceleration of the aqueous Diels-Alder reaction . Also the effect of surfactants on Diels-Alder reactions has been studied. This topic will be extensively reviewed in Chapter 4. [Pg.26]

Burning times for coal particles are obtained from integrated reaction rates. For larger particles (>100 fim) and at practical combustion temperatures, there is a good correlation between theory and experiment for char burnout. Experimental data are found to obey the Nusselt "square law" which states that the burning time varies with the square of the initial particle diameter (t ). However, for particle sizes smaller than 100 p.m, the Nusselt... [Pg.522]

This initial assignment is, of course, not at equilibrium. In particular, the expected velocity correlation between neighboring atoms is not guaranteed, and most likely it is nonexistent (i.e., in general, neighboring atoms, such as bonded pairs, are expected to... [Pg.48]

The first possibility envisages essentially the same mechanism as for the second-order process, but with Bt2 replacing solvent in the rate-determining conversion to an ion pair. The second mechanism pictures Bt2 attack on a reversibly formed ion-pair intermediate. The third mechanism postulates collide of a ternary complex tiiat is structurally similar to the initial charge-transfer complex but has 2 1 bromine alkene stoichiometry. There are very striking similarities between the second-order and third-order processes in terms of magnitude of p values and product distribution. In feet, there is a quantitative correlation between the rates of the two processes over a broad series of alkenes, which can be expressed as... [Pg.365]

If the polymer system was able to exist in an equilibrium state only, then a strictly defined correlation between (a, ph) and (a, ph) would exist in particular conditions, according to minimum of free energy of system formation. Consequently, there would occur only one temperature at which process initiation is thermodynamically probable. In rare ca.ses there may occur different correlations between ( ph, a) and ( ph, a ), which display one and the same value of free energy minimum of system formation. [Pg.366]

There is a clear correlation between quality or cost of materials and the durability/life expectancy of buildings. Greater resistance of better materials to wear and tear can be assumed, with obvious implications on future maintenance. Striking the best balance between initial capital outlay and maintenance cost requires complex calculations that take into account such intangibles as future interest rates and taxation of building operations. [Pg.57]

Different procedures for the precipitation, washing and thermal treatment of hydroxides result in different fluorine contamination levels in the final products - tantalum and niobium oxides. Laboratory and industrial experience confirms some correlation between the initial concentration of fluorine in the dried hydroxides and the fluorine content in the final oxides obtained after appropriate thermal treatment. For instance, it is reported in [499] that if the initial concentration of fluorine in niobium hydroxide equals A%, then the fluorine content in the final niobium oxide can be estimated according to the thermal treatment temperature as follows ... [Pg.302]

It is now well established that in lithium batteries (including lithium-ion batteries) containing either liquid or polymer electrolytes, the anode is always covered by a passivating layer called the SEI. However, the chemical and electrochemical formation reactions and properties of this layer are as yet not well understood. In this section we discuss the electrode surface and SEI characterizations, film formation reactions (chemical and electrochemical), and other phenomena taking place at the lithium or lithium-alloy anode, and at the Li. C6 anode/electrolyte interface in both liquid and polymer-electrolyte batteries. We focus on the lithium anode but the theoretical considerations are common to all alkali-metal anodes. We address also the initial electrochemical formation steps of the SEI, the role of the solvated-electron rate constant in the selection of SEI-building materials (precursors), and the correlation between SEI properties and battery quality and performance. [Pg.420]


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Correlation between

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