Paths satisfactory

In these gas-flow proportional counters, the windows are exceedingly thin, fragile,. and unavoidably leaky. Such a window is satisfactory only if a steady flow of. the filling gas is maintained at minimum pressure differential against the helium atmosphere in the optical path. The purging of impurities from the counter is an incidental benefit derived from the gas flow. Hendee, Fine, and Brown20 look upon the gas-flow proportional counter as a steppingstone on the road toward a windowless counter. 

In catalysis active sites are operative that allow for an alternative reaction path. For a satisfactory catalyst this alternative pathway leads to higher rates and higher selectivity. In heterogeneous catalysis reactant molecules adsorb at active sites on the catalyst surface at the surface sites reactions occur and products are desorbed subsequently. After desorption, active sites are again available for reactant molecules and the cycle is closed. In homogeneous catalysis the situation is essentially identical. Here complexation and decomplexation occur. A complication in heterogeneous catalysis is the need for mass transfer into and out of the catalyst particle, which is usually porous with the major part of the active sites at the interior surface. 

The route also provides a satisfactory path to some alkyl silicates for which no other satisfactory routes are available. Some of these alkyl silicates may be of interest in the synthesis of ceramics by the sol-gel technique. 

Cook et al (Ref 6) considered that the jump condition of NDZ theory is not a satisfactory solution, but that pressure in the reaction zone is limited to values no greater than the pressure P at the C-J plane, except possibly for an extremely short distance of perhaps several mean free paths at the extreme front where thermal equilibrium may not exist (Ref 7, p 174)... 

At the transition state the reaction coordinate is defined to be in the direction of the one normal coordinate which has a negative eigenvalue. Fukui (22) suggested that the reaction coordinate be defined as the line of steepest descents from the transition state to reactant or product regions on the potential surface. However, this definition fails to acknowledge the non-orthogonality of the internal coordinates and it would appear more satisfactory to define the reaction coordinate with respect to normal coordinates Q for all points on its path so that the line of steepest descent will be that for which (9r/9(2r) is a maximum (correspondingly all other derivatives (9V/ds r will be zero). 

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