Inherent kinetics

CSTRs, shell-and-tube reactors, and single-tube reactors, particularly a single adiabatic tube. Realistically, these different reactors may all scale similarly e.g., as but the dollar premultipliers will be different, with CSTRs being more expensive than sheU-and-tube reactors, which are more expensive than adiabatic single tubes. However, in what follows, the same capital cost will be used for all reactor types in order to emphasize inherent kinetic differences. This will bias the results toward CSTRs and toward shell-and-tube reactors over most single-tube designs. 

In the spontaneous self assembly approach to synthesis, the inherent kinetic lability of the Fe/Mo/S system allows for the fcnmation of various thermodynamically stable, heteronuclear products that, as of now, do not include one with the desir le Fe/Mo/S atom ratio of 6-7 1 6-8. 

The design and development of a Z-selective CM reaction faces two major challenges first, the thermodynamic preference for the formation of -olefms renders their Z-counterparts difficult to prepare second, any inherent kinetic Z-preference demonstrated by a catalyst can erode via secondary metathesis if the -pathway is not blocked. Consequently, most efforts to effect stereoselective olefin formation have focused on the preparation of -olefins. 

The mechanism of substitution reactions at saturated silicon centers is well studied, regarding both kinetics and stereochemistry13,14. In contrast, addition reactions to unsaturated silicon centers, such as to disilenes and silenes, are relatively unexplored. The reason is clear suitable substrates for investigations of regio- and stereochemistry and reaction kinetics are not readily available due to inherent kinetic instability of disilenes and silenes. Kinetically stabilized disilenes and silenes are now available, but these are not always convenient for studying the precise mechanism of addition reactions. For example, stable disilenes are usually prepared by the dimerization of silylenes with bulky substituents. Therefore, it is extremely difficult to prepare unsymmetrically substituted disilenes necessary for regio- and/or stereochemical studies. 

For a slow reaction, the mixing rates are all much faster than the inherent kinetics in this case the mixing and reaction processes are decoupled. For a motionless-mixer system, there must be sufficient residence time downstream of the mixer for the reaction to go to completion. For long reaction times, a stirred tank can be used to give the required residence time. The process then becomes ... 

When supersaturation of a crystallizing compound is created by its formation by chemical reaction, the operation is characterized as reactive crystallization. The reaction may be between two complex organic compounds or can be neutralization by an acid or base to form a salt of a complex compound. These reactions can be very fast compared to both the mass transfer rates to the crystals, and the growth rate of the crystals, thereby leading to high local supersaturation and nucleation. These operations are also known as precipitations because of the rapid inherent kinetics. 

Diffusion, partition, and enzyme,reactions influence the sensor characteristics in a complex manner. The effect of enzyme immobilization on the reaction rate is described by the following terminology. Apparent or effective kinetics are observed when internal or external diffusion affects the overall rate. Inherent kinetics prevail when only partitioning (and not mass transfer) effects are present. Intrinsic kinetics describe the enzyme-catalyzed reaction when no partitioning effects or diffusion limitation are present. 

Inherent kinetics is the behavior observed in the absence of mass transfer limitations. This behavior, and the corresponding kinetic parameters, may differ from the intrinsic because of partition of the reactive species between the biocatalyst phase, where the reaction occurs, and the bulk medium phase, where the reaction is monitored. 

Closer approach is prevented by the repulsive forces then arising out of quantum-mechanical resonance effects. The column headed in the table contains those minimum distances which prevail at room temperature in consequence of thermal agitation. They are somewhat smaller than those considered heretofore because the repulsive forces are overcome to a slight extent by the inherent kinetic energy of the separate parts of the molecule. 

An intricate system of interrelated control mechanisms regulate biochemical reaction sequences. Metabolic pathways are controlled not only by specific activity and inherent kinetic properties of enzymes in the pathway but also by the intracellular concentration of certain essential substrates, activators or inhibitors. PP-ri-bose-P is an essential substrate of purine, pyrimidine and pyridine biosynthesis. The intracellular concentration of PP-ribose-P represents a balance between its synthesis by PP-ribose-P synthetase and its utilization which is catalyzed by several different phosphori-bosyltransferase (PRT) enzymes as well as non-specific phosphatases. Alterations in the rate of synthesis or degradation of PP-ribose-P, whether drug induced or secondary to an inborn error, could potentially change the intracellular concentration of this compound. 

It was found that the OBR could achieve the batch product specification in a residence time one tenth that of the batch reactor (2h). This was because the reaction was able to proceed at its inherent kinetic rate due to the improved mixing characteristics of the OBR, i.e. the reaction was no longer mixing-controlled. 

A subtle distinction is that typically when we discuss strong versus weak Lewis acid-bases, we are making a thermodynamic distinction. This contrasts the inherently kinetic nature noted above when evaluating nucleophiles and the like. 

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