Control of condensation

The concept of coherent control, which we have developed with isolated molecules in the gas phase, is universal and should apply to condensed matter as well. We anticipate that the coherent control of wave functions delocalized over many particles in solids or liquids will be a useful tool to track the temporal evolution of the delocalized wave function modulated by many-body interactions with other particles surrounding itself. We may find a clue to better understand the quantum-classical boundary by observing such dynamical evolution of wave functions of condensed matter. In the condensed phase, however, the coherence lifetime is in principle much shorter than in the gas phase, and the coherent control is more difficult accordingly. In this section, we show our recent efforts to develop the coherent control of condensed matter. 

The fact that silanol persistence can be favored by equilibrium conditions rather than control of condensation kinetics by steric or electronic factors is usually not considered. The phase separation which results from highly condensed systems continuously removes material from deposition solutions, depleting soluble silane species. While condensed silanols or siloxanes are typically not regarded as participating in a reversible reaction with water or alcohol, they do indeed participate in an equilibrium reaction. Iler [16] has shown that even hydrated amorphous silicon dioxide has an equilibrium solubility in methanol, which implies the formation of soluble low molecular... 

Similar polycondensation giving crystals was attained by the reaction of 4-hydroxybenzoic acid with 4-ethoxybenzoic acid anhydride, which immediately affords 4-(4-ethoxybenzoyloxy)benzoic acid, a monomer, and monofunctional compound [260]. Polyesters with a DP of 38-76 were obtained even if 30-60 mol % of the anhydride was added to the reaction mixture (Scheme 67). This polycondensation is noteworthy not only as a stoichio-metrically imbalanced polycondensation, but also as a valuable method for morphology control of condensation polymers during polymerization [261]. 

Assessment of the Controllability of Condensible Emissions U.S. Environmental Protection Agency, 1990, EPA/600/S8-90/075. 

Control of condensers by flooding part of the area with condensate is not recommended for several reasons ... 

Whether sufficient heat has been removed to totally condense a vapor can be determined by the temperature of its condensate, if constant pres sure prevails, or more accurately, by vapor pressure if the vessel is closed. Control of condensate temperature or vapor pressure is not so straightforward since the flow of the condensing vapor is the load and not the manipulated variable. The relationship between heat transfer and cool-, ant flow Wc can be found simply by solving the equations developed earlier using constant temperature for the condensing vapor ... 

For many columns the vent flow functions primarily as a purge and is small enough that moderate changes do not affect column operation. In such cases a manually set vent or bleed valve is often adequate and no direct control of condensate subc(X)ling is necessary. For other cases, where column feed rate varies significantly, the vent or bleed valves may be tied to the pressure controller to work in parallel with the condenser cooling-water valve. An example is shown in Figure 3.13. 

Level Control of Condensate Receiver and Required HMup... 

To what extent does the structure-property-activity dogma, with its simulation-prediction sub-dogma, really work in practice Many obstacles stand in the way. Present theories of molecular aggregation are tentative (Chapter 15), so that the prediction and control of condensation modes from molecular structure alone cannot yet... 

Complete controlled of condensation polymerization by substituent effect-assisted CGCP was first demonstrated in the synthesis of N-alkylated poly(p-benzamide)s by polymerization of 4-(alkylamino)benzoic acid phenyl esters 14 [20]. Polymerization of phenyl 4-(octylamino)benzoate (14a) was carried out in the presence of a base and the initiator 15a, yielding poly(p-benzamide) with a low polydispersity and controlled molecular weight based on the feed ration of 14 to 15a ([14]o/[15a]o) (Scheme 11). 

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