Theory[ edit ] Long-term memory is stored in cell structures and molecules within the brain. Cryonics controversially asserts that a human survives even within an inactive brain that has been badly damaged, provided that original encoding of memory and personality can, in theory, be adequately inferred and reconstituted from structure that remains. Cryonicists argue that true "death" should be defined as irreversible loss of brain information critical to personal identity, rather than inability to resuscitate using current technology. Cryopreservation may be accomplished by freezing, freezing with cryoprotectant to reduce ice damage, or by vitrification to avoid ice damage.
The word cryogenics comes from the Greek word cryosmeaning "cold," combined with a shortened form of the English verb "to generate. More specifically, a low-temperature environment is termed a cryogenic environment when the temperature range is below the point at which permanent gases begin to liquefy.
Permanent gases are elements that normally exist in the gaseous state and were once believed impossible to liquefy.
Among others, they include oxygen, nitrogen, hydrogen, and helium. The origin of cryogenics as a scientific discipline coincided with the discovery by nineteenth-century scientists that the permanent gases can be liquefied at exceedingly low temperatures.
The temperature of any material—solid, liquid, or gas—is a measure of the energy it contains. That energy is due to various forms of motion among the atoms or molecules of which the material is made. A gas that consists of very rapidly moving molecules, for example, has a higher temperature than one with molecules that are moving more slowly.
InEnglish physicist William Thomson later known as Lord Kelvin; — pointed out the possibility of having a material in which particles had ceased all forms of motion.
The absence of all forms of motion would result in a complete absence of heat and temperature. Thomson defined that condition as absolute zero. Words to Know Absolute zero: The lowest temperature possible at which all molecular motion ceases.
A temperature scale based on absolute zero with a unit, called the kelvin, having the same size as a Celsius degree. The ability of a material to conduct electricity without resistance. That scale has units the same size as the Celsius temperature scale but called kelvin units abbreviation K.
Absolute zero is represented as 0 K, where the term degree is omitted and is read as zero kelvin. One can convert between Celsius and Kelvin scales by one of the following equations: One aspect of cryogenics involves the development of methods for producing and maintaining very low temperatures.
Another aspect includes the study of the properties of materials at cryogenic temperatures. The mechanical and electrical properties of many materials change very dramatically when cooled to K or lower. For example, rubber, most plastics, and some metals become exceedingly brittle.
Also many metals and ceramics lose all resistance to the flow of electricity, a phenomenon called superconductivity. In addition, helium that is cooled to very nearly absolute zero 2. In this state, helium can flow through exceedingly narrow passages with no friction. History Cryogenics developed in the nineteenth century as a result of efforts by scientists to liquefy the permanent gases.
One of the most successful of these scientists was English physicist Michael Faraday — ByFaraday had managed to liquefy most permanent gases then known to exist. His procedure consisted of cooling the gas by immersion in a bath of ether and dry ice and then pressurizing the gas until it liquefied.
Six gases, however, resisted every attempt at liquefaction and were known at the time as permanent gases.
They were oxygen, hydrogen, nitrogen, carbon monoxide, methane, and nitric oxide. The noble gases—helium, neon, argon, krypton, and xenon—were yet to be discovered. Of the known permanent gases, oxygen and nitrogen the primary constituents of airreceived the most attention.The practice of freezing an entire human body after death in the hope of later restoring life is known as cryonics, but it is not an accepted scientific application of cryogenics.
The freezing of portions of the body to destroy unwanted or malfunctioning tissue is known as cryosurgery. Nov 18, · Watch video · Cryogenic freezing is the process of preserving a dead body with liquid nitrogen.
Advocates believe that scientists will one day work out how to warm the bodies up and bring them back to life, by which time doctors might be able to cure cancer and other diseases which are untreatable rutadeltambor.com: Reiss Smith.
Liquid Nitrogen vs. Carbon Dioxide Food Freezing Liquid Nitrogen and Carbon Dioxide can be used interchangeably in many food freezing applications. Freezing is a phase transition in which a liquid turns into a solid when its temperature is lowered below its freezing point.
In contrast, solidification is a similar process where a liquid turns into a solid, not by lowering its temperature, . Other applications of cryogenics include fast freezing of some foods and the preservation of some biological materials such as livestock semen as well as human blood, tissue, and embryos.
The practice of freezing an entire human body after death in the hope of later restoring life is known as cryonics, but it is not an accepted scientific application of .
The Applications of Cryogenic Freezing in Everyday Life PAGES 3. WORDS View Full Essay. More essays like this: cryogenic freezing, cooling perishable items, liquid nitrogen, cryogenic temperature. Not sure what I'd do without @Kibin - Alfredo Alvarez, student @ Miami University.