Cryogenics
Cryogenics is a largely growing field, relatively innovative in the field of science and research. It deals with freezing temperatures below –150 degrees Celsius (-238 degrees Fahrenheit) using oxygen, helium I, helium II (which are both are chemically identical), and nitrogen. These are cooled to the point of liquidation and used to freeze diverse materials and substances. “At these extreme conditions, such properties of materials as strength, thermal conductivity, ductility and electrical resistance are altered…materials at cryogenic temperatures are as close to a static and highly ordered state as possible.” Cryogenics is more than the term for freezing, but more precisely for temperatures below –150 degrees Celsius. “Cryogenic temperatures are achieved either by rapid evaporation of volatile liquids or by the expansion of gases confined initially at pressures of 150-200 atmospheres.” This ability to freeze materials at such low temperature aids in the exploration of human research and development as well as freeze-dried foods, and aeronautics.
Among the different materials that can be cryogenically frozen, food is almost certainly the most familiar one. Liquid nitrogen is used in this process by being sprayed onto the food. This causes the heat to completely absorb from the food and the food is then preserved. This is most commonly known as “astronaut food” and is not only used in space, but also for people needing to carry light loads like extreme hikers or mountain bikers.
The human body can also be frozen in different ways and as a whole or in parts. Body parts such as a knee or elbow are frozen and can be later used for medical students or more recently in other people. Orthopedic tissue su...
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8. Schachtman, Tom. Absolute Zero and the Conquest of Cold. Houghton, 1999. The history of cold technology and its importance in the 20th century.
9. Walpole, Brenda. Temperature (Measure Up with Science). Gareth Stevens, 1995. An introduction to temperature concepts for younger readers.
10. Bryson, William E. Cryogenics. Book News, Inc.1999 Aimed at a non-scientific business audience, this book explains some of the cryogenic processes that may be used to improve wear and stress performance of metal and other materials.
The temperature probe was placed into the test tube and recorded the temperature of the freezing solution using Logger Pro software. The test tube was held against the inner glass of the ice bath beaker so the test tube was visible to see when the solution froze over. Once the freezing point was measured, the temperature stopped being monitored and the data was recorded. The steps mentioned above for finding the freezing point, also known as ΔTf, was replicated for the 0.0, 0.4, and 0.6 concentrations. To find the freezing point depression, the equation ΔTf = imKf was used. The molality (m) of each solution was then calculated dividing moles of solute by kilograms of solvent, and the Kf value for magnesium chloride is known to be -1.86. Since magnesium chloride breaks down into three ions in deionized water, it was concluded that the Van’t Hoff factor couldn’t exceed three. For better accuracy, the experiment explained above for finding the freezing point depression and Van’t Hoff factor was re-conducted exactly the same to determine more accurate results. Again, the molality of each solution was calculated, and a graph expressing the change in freezing temperature verses molality
Plasma is one of the three components of blood and contains all the clotting factors found in blood. From the plasma many different products are manufactured, these are fresh frozen plasma or when the plasma is split into its different components. Plasma is obtained from voluntary donors who donate just plasma via an apheresis machine or they donate whole blood which then gets centrifuged to separate the plasma from the rest of the blood.
The first was to see how long it would take to lower body temperature, and the next to decide how best to resuscitate a frozen victim. The doctors submerged a naked victim in an icy vat of water. They would insert an insulated thermometer into the victim’s rectum in order to monitor his or her body temperature. The icy vat proved to be the fastest way to drop the body’s temperature. Once the body reached 25 degrees Celsius, the victim would usually die.
The Cold war was powered by many factors, but it can be made clear how hugely both military-industrial manufacturers and the secret services impacted the events and final outcome; actions made by the CIA and KGB became historical turning points, just as the rapid improvements and discoveries made in the field of technology has revolutionised the world today.
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“John first took leftover prescription painkillers and numbed his left foot in ice water to reduce impending pain. He then buried his foot in dry ice for six hours to induce severe frostbite and force surgeons to operate” (Adams, 2007).
were rapidly frozen can be stored in “banks” for later use. Then skin can be
* Heat and Cold Therapy has been used for centuries to manage soft tissue and joint injuries while relieving pain.
Retrieved December 30, 2013, from http://www.benbest.com/cryonics/CryoFAQ.html#_VD_.
Nowadays, refrigeration and freezing had become the most popular method for food preservation. It is a desirable way to preserve food because at low temperatures which around –10°C to –25°C, chemical reactions very slowly thus it will make the bacteria in food hard to survive.