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Solvent vapor annealing (SVA) is a widely used technique for controlling the morphology and ordering of block copolymer (BCP) films. [1] [2] [3] By controlling the block ratio (f = NA/N), spheres, cylinders, gyroids, and lamellae structures can be generated by forming a swollen and mobile layer of thin-film from added solvent vapor to facilitate the self-assembly of the polymer blocks. [4]
The solubility of gas obeys Henry's law, that is, the amount of a dissolved gas in a liquid is proportional to its partial pressure. Therefore, placing a solution under reduced pressure makes the dissolved gas less soluble. Sonication and stirring under reduced pressure can usually enhance the efficiency.
diagram of a double-effect falling film evaporator. Condensing vapors from flash tank B1 heat evaporator A2. •1=feed •2=product •3=steam •4=vapors. In chemical engineering, a multiple-effect evaporator is an apparatus for efficiently using the heat from steam to evaporate water. [1]
An increase in solvent polarity decreases the rates of reactions where there is less charge in the activated complex in comparison to the starting materials; A change in solvent polarity will have little or no effect on the rates of reaction when there is little or no difference in charge between the reactants and the activated complex. [6]
The vapor-compression evaporation process replaced the once-through steam generators (OTSG) traditionally used for steam production. OTSG generally ran on natural gas which in 2008 had become increasingly valuable. The water quality of evaporators is four times better which is needed for the drum boilers.
A rotary evaporator [1] (rotovap) is a device used in chemical laboratories for the efficient and gentle removal of solvents from samples by evaporation.When referenced in the chemistry research literature, description of the use of this technique and equipment may include the phrase "rotary evaporator", though use is often rather signaled by other language (e.g., "the sample was evaporated ...
The gas outlet may itself be surrounded by a spinning mesh screen or grating, so that any liquid that does approach the outlet strikes the grating, is accelerated, and thrown away from the outlet. The vapor travels through the gas outlet at a design velocity which minimises the entrainment of any liquid droplets in the vapor as it exits the vessel.
Evaporation is a type of vaporization that occurs on the surface of a liquid as it changes into the gas phase. [1] A high concentration of the evaporating substance in the surrounding gas significantly slows down evaporation, such as when humidity affects rate of evaporation of water. [ 2 ]