What is the meaning of sublimation?
"Sublimation" has slightly different meanings, albeit related ones, in psychology and chemistry.
In psychology, sublimation is the act, conscious or unconscious, of taking a form of energy and redirecting that energy toward a constructive purpose. This might be sexual energy or anger, for example, that one cannot express for some reason. Have you every been angry or dissatisfied and engaged in a cleaning spree? You have redirected that energy. I believe this concept originated with Freud, but perhaps a psychologist can speak to that.
In chemistry, and other sciences, sublimation is the act of purifying or refining some substance. One act that comes to mind is that of taking plasma from blood. I would imagine that is an act of sublimation.
Sublimation is the process of change of state by a chemical element/ substance from the solid state directly to a gaseous state without transiting to the liquid state in between. The reverse process of the gas solidifying back is also possible as in the formation of frost. Many interesting examples of Sublimation process occur in our daily lives; dry ice (solid carbon dioxide), Napthalene balls (white moth balls used to ward off insects), ice cubes from the trays inside the freezer, Iodine crystals, snow, camphor & toilet freshner cakes (para dichlorobenzine). This depends on the vapor pressure of the material and the prevailing temperature, pressure conditions. Sublimation has useful applications in printing, chemical purification, frost-free refrigeration, etc. Zinc, cadmium, ammonium chloride and arsenic also exhibit this ability under some conditions.
Respecting the other's views, this is a view pertaining to thermodynamics. We know that substances have three states of existence - solid , liquid and gas. The pressure and temperature are very much the cause for these 3 three states of the substance. We know that for a given pressure there exist a range of temperatures in which a substance can exist in solid, liquid or gaseous state. If we heat the solid substance it may turn liquid and if we futrher heat it boils and entirely turns to gaseous state. However , there is a unique pressure and temperature for each substance, at which all three phases of the substance coexist. This unique pressure and temperature of the substance is called the tripple point of the substance.Below this tripple point pressure, if we heat substance it does not liquify but directly evaporates or turns gaseous. This process of evapourating from the solid phase directly to the gaseous phase is called sublimation.
The ice has the tripple point at 0.01deg Centigrade under 0.006 Atmospheric pressure. So, ice sublimates below 0.06 atm pressure and below 0.01 deg C. In space where, the atmospheric pressure is zero (or less than 0.006 atm pressure) this phenomina of ice turning to vapour happens without entering the liquid (water) state. You can understand how a situation of pressure_condtioning is necessary for the outer space entering living beings( humans or animals) and think of water content of their body and blood, had there been no maintenace of these eath friendly situation.
In chemistry, sublimation is when a substance goes from a solid state to a gas state skipping the liquid staTe.
Sublimation is a defense mechanism described by Sigmund Freud that people can take aggressive feelings and apply that to be used for a positive thing. For example, an angry person would use sublimation when they sign up for the wrestling team or the football team. That person would use their aggressive behavior and put it into use into an activity that is acceptable of that aggression.
In psychology, sublimation is changing those unwanted desires into something socially acceptable.
There are three phases of matter: solid->liquid->gas /gas->liquid -> solid. Sublimation is when a material goes directly from the solid phase to the gas phase, skipping the liquid phase. When a substance goes directly from gas to solid without going through the liquid phase, this is also considered sublimation. An example would be dry ice, which is often used in fog machines or to pack meats that are shipped to homes.