Reduction synchronic

The foundations of any turbogenerator installation play a significant part in the safe operation of the machine. Industrial turbines will normally operate at above synchronous speed and will drive an alternator via a reduction gearbox. Any vibration or out of balance occurring under both normal or abnormal operation must be accommodated by the foundations, and their design should therefore best be undertaken by a specialist organization. The layout... 

It is hypothesized that cells proliferate uniformly and that the distribution of cell cycle phases is synchronized in the G0/G1 phase in the PMBV/PVA hydrogel. It has also been reported that cells synchronized at G0/G1 phase express a high level of cell-specific functions [59]. Thus, it is expected that the PMBV/PVA hydrogel can avoid a reduction in activity of entrapped cells and preserve cells with high functionality. 

In a closely related study, Tung and Sun discussed the microwave-assisted liquid-phase synthesis of chiral quinoxalines [80], Various L-a-amino acid methyl ester hydrochlorides were coupled to MeOPEG-bound ortho-fluoronitrobenzene by the aforementioned ipso-fluoro displacement method. Reduction under microwave irradiation resulted in spontaneous synchronous intramolecular cyclization to the corresponding l,2,3,4-tetrahydroquinoxalin-2-ones (Scheme 7.71). Retention of the chiral moiety could not be monitored during the reaction, but after release of the desired products it was found that about 10% of the product had undergone racemization. 

Transfer of hydrogen occurs exclusively in a syn manner and it has been concluded that the reduction of a multiple bond by diimide involves a synchronous transfer of a pair of hydrogens to a single face of the carbon-carbon double bond via a six-membered cyclic transition state to give a syn adduct (equation 22)77,81. 

The most noticeable effect of low temp upon stable deton results from a shrinkage in vol. Because of the higher d at low temps, deton velocities, and consequently deton pressures, are higher. These increases are too small to have practical significance. Where propagation time is critical, and must be synchronized with a process that is independent of temp, this effect, now accentuated by reduction in distance, can be a source of difficulty (Ref 2)... 

Furthermore, synchronization of contraction is facilitated by gap junctional communication as well as synchronization of electrical activation. The electrical coupling between cardiomyocytes mitigates differences in the membrane potential between these cells, for example in the course of an action potential if both cells repolarize at different timepoints. This results in smaller differences in the repolarization times thereby causing a reduction in the dispersion of the action potential duration. Since increased dispersion is known to make the heart more prone to reentrant arrhythmia, sufficient gap junctional communication can be considered as an endogenous arrhythmia-preventing mechanism. For a detailed discussion of the role of gap junctional communication in the biophysics of cardiac activation as related to anisotropy, nonuniformity and stochastic phenomena, see chapter 1 for a discussion of their role in arrhythmia, see chapter 6, and for a possible pharmacological intervention at the gap junctions for suppression of arrhythmia, refer to chapter 7. 

It was found that most synthetic processes that are employed to prepare the diimide reagent generate trans-diimide, but ds-diimide undergoes faster hydrogen atom transfer to a double bond than does the trans isomer. It follows that a fast trans-cis isomerization precedes reduction. The transfer of hydrogen atoms takes place in a synchronous process188 via the transition state 19 ... 

Oxidation of oxalic acid with dimethyl-V,V-dichlorohydantoin and dichloroisocya-nuric acid is of first order with respect to the oxidant. The order with respect to the reductant is fractional. The reactions are catalysed by Mn(II). Suitable mechanisms are proposed.129 A mechanism involving synchronous oxidative decarboxylation has been suggested for the oxidation of a-amino acids with l,3-dichloro-5,5-dimethylhydantoin.130 Kinetic parameters have been determined and a mechanism has been proposed for the oxidation of thiadiazole and oxadiazole with trichloroiso-cyanuric acid.131 Oxidation of two phenoxazine dyes, Nile Blue and Meldola Blue, with acidic chlorite and hypochlorous acid is of first order with respect to each of the reductant and chlorite anion. The rate constants and activation parameters for the oxidation have been determined.132... 

In a recent survey [19] it was noted that a realistic model for catalytic oxidation reactions must include equations describing the evolution of at least two concentrations of surface substances and account for the slow variation in the properties of the catalyst surface (e.g. oxidation-reduction). For the synchronization of the dynamic behaviour for various surface domains, it is necessary to take into consideration changes in the concentrations of gas-phase substances and the temperature of the catalyst surface. It is evident that, in the hierarchy of modelling levels, such models must be constructed and tested immediately after kinetic models. On the one hand, the appearance of such models is associated with the experimental data on self-oscillations in reactors with noticeable concentration variations of the initial substances and products (e.g. ref. 74) on the other hand, there was a gap between the comprehensively examined non-isothermal models with simple kinetics and those for the complex heterogeneous catalytic reactions... 

---