HW-1-2010-history-2001-09

HW-1-2010-history-2001-09 - Why are safety reliefs...

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Unformatted text preview: Why are safety reliefs installed on all cryogenic liquid oxygen, nitrogen, argon or carbon dioxide fill hoses? Safeties are not only installed on fill hoses. They are also installed on any cryogenic line that is sealed on both sides. This is because cryogenic liquid trapped in a line will vaporize and expand exponentially, creating tremendous pressure in hoses, piping or tubing. This expanding liquid nitrogen, oxygen, argon, or CO2 can easily build enough pressure to cause the line or hose to explode with great force. This is a danger that is easily overlooked and one that is not obvious to someone without prior knowledge or training. Whether you are filling medical oxygen bases, transferring liquid from one DOT4 vessel to another, or otherwise filling from a bulk source, it is essential to have a relief for expanding vapor. Never forget to be sure the hose you are using to fill has a properly rated safety relief installed somewhere between the valves or other connections that could trap liquid! http://cryonews.blogspot.com/ C la re n c e B i rd s e y e • • • • • • • • Designer of freezing equipment, father of frozen food industry in US 1912-15, field naturalist for US Biological Survey in Canada, saw Eskimos place fresh fish on ice, expose to wind, freeze solid. Fish thawed and eaten much later retained all fresh characteristics (flesh quality, taste) Realized flash freezing prevented formation of large crystals, no damage to cellular structure of food Worked to perfect freezing methods from 1917 - 1925 Patent for wax-packing dressed foods in cartons were frozen between two flat refrigerated surfaces under pressure 1930 First retail sale of frozen foods, Springfield MA Contracted production of retail display units for grocery stores Held 300 patents •Invented by Donald Glaser in 1952 •Glaser won the Nobel Prize in Physics for this in 1960 •Glaser was POSSIBLY inspired by bubbles in beer •Vessel filled with a clear , superheated liquid •Normally filled with Liquid Hydrogen because of its simplicity and low interference with the high-energy process being studied •Used to detect electrically charged particles •The device uses a piston in a chamber to decrease pressure resulting in bubbles forming. The bubble density is proportional to a particle’s energy loss. •Chamber is in a magnetic field to force the charged particles to move in a helical path. •Led to the discovery of weak neutral current, establishing the electroweak theory •Being replaced by wire chambers and spark chambers. Sources: Cryogenic Engineering Text Book Wikipedia Ted Williams The infamous baseball player died on July 5, 2002. Although his will stated that he wanted to be cremated, his children decided to have him cryogenically frozen at Alcor, a crogenics facility. Since this time, there has been much controversy over this decision to cryogenically freeze Williams, including a lawsuit by the other siblings, and stories of his frozen head being damaged during a handling process. Celebrities use the technology of cryogenics to suspend their bodies and cells with the possibility of someday being unfrozen and capable of living on. Daniel Amariutei, PHY 6555C, HW1: Lowest temperatures achieved, pK-range. 2003: 500pK MIT team headed by Nobel laureate Wolfgang Ketterle, has cooled a sodium gas to 500 picokelvin using lasers and a novel way of confining atoms, which they call a "gravito-magnetic trap" - the magnetic fields act together with gravitational forces to keep the atoms trapped. A view into the vacuum chamber where sodium atoms were cooled. 2008: 100pK Helsinki University of Technology, YKI-group of the Low Temperature Laboratory has cooled a rhodium sample to 100 picokelvin using an apparatus consisting of several consecutive cooling stages. The central part is dilution refrigerator reaching a temperature of 3 mK, and two nuclear cooling stages utilizing the method of adiabatic nuclear demagnetization (first nuclear stage cools to 50mK and the second nuclear stage cools in the pK range). September 2003 – MIT Team Achieves Lowest Temperature – 500 pK • Accomplished by Dr. Wolfgang Ketterle, who discovered Bose-Einstein Condenstate in 1995, and Dr. David Pritchard both from MIT • Cooled sodium gas to 500pK, 6 times lower than the previous record • Used the same process to cool the atoms that led to the 2001 Nobel Prize in Physics shared by Ketterle and his colleagues Drs. Eric Cornell and Carl Wieman from the University of Colorado • To contain the gas, they invented a novel way of confining atoms they termed a “gravito-magnetic trap,” using magnetic fields in conjunction with gravitational forces to contain them Source: http://cua.mit.edu/ketterle_group/Press/press_picokelvin/Universe%20Today%20-%20Coldest%20Temperature%20Ever%20Created.pdf Low Temperature Record Reached in 2003 Wolfgang Ketterle and colleagues at MIT have succeeded in cooling a Bose condensate of sodium atoms down to a low temperature six times lower than the previous record for Bose condensates. The lowest temperature the team measured was 450 pK.1 As of November 2000, temperatures below 100 pK were reported at the Helsinki University of Technology. However this was the temperature of nuclear-spin.2 4.5×10-10 1. 2. A Leanhardt et al. 2003 Science 301 1513; http://ltl.tkk.fi/wiki/LTL/World_record_in_low_temperatures. Coldest Temperature in Nature Observed • 2003 • The Boomerang Nebula • 1K (-272 degrees C) • http://www.esa.int/esaSC/Pr_1_2003_h_en.html Direct Observation of Fermionic Condensates (2003) Using K-40 atoms and Fesbach Resonance −8 at a T of 5×10 K the first true observation of a fermionic Condensate Deborah S. Jin Left: Public Domain picture from http://www.nist.gov/public_affairs/releases/jin.htm Right: False-color snapshots of a growing fermionic condensate. Copyright Markus Greiner. Adiabatic Demagnetization Refrigerator (ADR) --Developed by Dr. Peter Shirron at NASA --A solid state refrigerator that uses magnetism to achieve temperatures far below 2K. Changes in the angular momentum of the magnetic “refrigerant’s” electrons result from manipulation of an external magnetic field, and cause the material to store or release heat by changing the system’s entropy. --Applications in space/astronomy Because of the ability to reach very low temperatures, and the fact that it does not rely on gravity to operate (like a dilution refrigerator does). See: http://www.techbriefs.com/component/content/article/5331?start=3 Technology originally discovered in the 1990s to aid in the safety of opening contaminant barrels. It was made available in 2003 to scientists as a product under the name Nitrojet ­ licensed in 2001. USES: •  ariable temperature and pressure of LN V stream cuts allows cutting through “difficult” material ­ such as steel and concrete •  leans and decontaminates industrial and C radioactive material. •  nert LN sprays into a gas a distance of 18” I before being absorbed by the atmosphere •  ressure ranges: 6000 – 55,000 psi P •  emp ranges: 100 to  ­240 F T •  low rate: 1 – 8 GOM (total F •  ower req: 480 V, 3 phase, 150 KVA P All information and photos taken from http://www.nitrocision.com/ Supersolid ● In 2004 Moses Chan observed a separation of solid helium from its container. Here is the test mass containing the 'supersolid' When spun, not all the mass is given a rotational velocity. ● ● Staring in 2001, the non-profit Alcor Life Extension Foundation had performed ice-free preservation of the brain (ice damage was well known and a problem), using a process known as vitrification, essentially an antifreeze application for organic materials. However, in 2005, Alcor extended this process from just the isolated brain to the brain inside the head of a subject while still attached to the body. The result was a vitrification of the brain and a “conventional” cryo-preservation of the body. It is hoped from this that the next step is full vitrification of the entire body. This large Dewar is designed to preserve four bodies and six brains. *http://www.alcor.org/Library/html/newtechnology.html Cryopreservation • • • • • • Goal: Reduce temperature of tissue below point of biological activity Desired temperature is below glass transition point of water (-136 Celsius) Glass transition/Vitrification: Occurs upon very rapid cooling; forms amorphous ice (glassine structure, no crystalization) Crystalization is undesirable because of the subcellular damage that crystals can cause (esp. crushing/rupturing cell membrane) For vitrification, cooling must be very rapid Minimum cooling rate increases with viscosity, depression of freezing temperature Common fix: introduce cryoprotectant (similar to anti-freeze) Most common cryoprotectant: Dimethyl sulfoxide (toxic) Current cryopreservation research focused on finding appropriate cryoprotectant To attain vitrification of pure water, necessary cooling rate estimated to be on the order of 10^6 Kelvin per second, thought impossible until 2005 research by Bhat, Sharma, and Bhat. Researchers that water is capable of undergoing the glass transition in bulk. Researchers exposed capillaries of water to liquid Helium (4.2K) Resulting amorphous ice was examined and confirmed with Spin Probe Electron Spin Resonance (ESR) Top picture: damaged brain tissue caused by ice crystal formation (white structure is a damaged capillary, black spot is a nucleus sans cell membrane Bottom picture: micro-formation of damaging ice crystals • • • • • • • • Iron‐based Superconductor • Discovered in 2006 and 2008; • Ferropnictides, based on the iron‐pnictogen (typically arsenic) layers (Cuprates are based on layers of copper and oxygen); • With alkaline earth metal being substituted by rare earth metal, Critical Temperature may be higher than 40K (39K is the McMillan limit predicted by BCS theory); • Tc may increase under high pressure; • Some types may have very high upper critical field (Hc ~ 50‐100T) Superinsulators • In 2008, physicists found that under certain conditions, metals cooled to temperatures near absolute zero will form superinsulators rather than superconductors. • Compound used and observed was titanium nitride film placed in a magnetic field. • “Vinokur points out that a superinsulator material could be used to encapsulate a superconducting wire. Such a coupling would create an almost perfect wire in which virtually no energy is lost as heat.” Cryogenics as a Coolant: Cooling the The LHC uses liquid helium [in its LHC superfluid stage around 1.9 K] Though cryogenic techniques represent an obvious method of cooling, they have never been used to cool anything on the scale of CERN's Large Hadron Collider (LHC). Source: University College London, <http: //www.hep.ucl.ac.uk/undergradprojects/3rdyear/PPguide/cool.htm> This is used to keep the coppershelled niobium-titanium magnetic coils that serve as magnets in a superconducting state The use of superfluid helium allows for "kilowatts of refrigeration to be transported over more than a kilometer with a temperature drop of less than 0.1 K." During the initial cooldown (from ambient temperature to superconducting temperature), over 12 million liters of liquid nitrogen will be used. The total amount of liquid helium stored for use in the LHC is 700,000 liters. Use of cryogenics at the Laser Interferometer Gravitational Wave (GW) Observatory (LIGO) The LIGO detector is designed to measure gravitational radiation in the frequency range from 10Hz – 1kHz. 4km Laser Interferometer: To achieve the necessary sensitivity to see GW, LIGO must measures the distance between the mirrors to within an accuracy of 1 attometer (10-18 m) Cryogenic cooling of the mirrors: ● reduces thermal noise ● reduces thermal lensing Science run 6 (S6) began on July 7, 2009 For more Information, refer to: http://www.iop.org/EJ/article/0264-9381/19/7/412/q207b2.pdf?request-id=f10ce0f3-0319-4042-b502-f3b7f6785de4 Shawn Mitryk - Cyrogenics Cryogenics Breakthrough Event Bose-Einstein condensate of strontium produced for first time (2009) Scientists from the Institute of Quantum Optics and Quantum Information produced a Bose-Einstein condensate of the alkaline-earth element strontium. Key to the discovery was the scientists’ choice of 84Sr, an isotope that is not as abundant in nature as other strontium isotope candidates like 86Sr and 88Sr. Their research showed that the 84Sr isotope had an ideal scattering length for producing a Bose-Einstein condensate. In experiments where strontium atoms were cooled to near absolute zero in a optical trap, a BoseEinstein condensate of 150,000 atoms was produced. Mariugenia Salas (UFID 9629-0158) Planck instruments’ reach coldest known temperature in outer space July 3, 2009 – Planck’s High Frequency Instruments reached an operational temperature of 0.1 K, said to be the coldest temperature in outer space. Planck detectors are equipped with three cryogenic, cooling systems (final -stage cooling by a 0.1 K dilution system) working in succession to lower the operational temperature from 45 K to 0.1 K. (Left: Spacecraft’s three “V-groove”-panels for thermally isolating the payload from high temperatures and improve in radiating excess heat. Right: Planck’s Low and High Frequency Instruments (LFI and HFI) spacecraft used for imaging the sky in six frequency channels between 100 and 857 GHz.) Source Article- http://sci.esa.int/science-e/www/object/index.cfm?fobjectid=45133 Left Image- http://planck.cf.ac.uk/files/images/09Feb2009-3120_L.jpg_0.jpeg Right Image- http://www.asc-csa.gc.ca/images/planck3.jpg Cryogenic Testing of NASA Space Telescope On April 9, 2009, parts of the James Webb Space Telescope (JWST) successfully endured cryogenic testing at an X-Ray and Cryogenic facility at the Marshall Space Flight Center. The JWST represents a new era is deep space telescopes: it is far larger and lighter per sq. meter than Hubble and will be kept at cryogenic temperatures by blocking solar radiation and being sent ~ 1 million miles from Earth. This will allow for infrared images of space without interference from infrared radiation from the telescope itself. Cryogenic testing of all telescope parts is necessary to insure functionality of the instrument in the near absolute zero temperatures of space. The mirror segments are composed of beryllium as it is a nonmagnetic metal that doesn't distort significantly over a wide range of temperatures. One of the 18 mirrors was cooled to 25 K in a vacuum chamber cooled via liquid helium in order to asses the contraction and expansion of the mirror components as the temperature varied. Accounting for such unexpected changes during temperature fluctuations is imperative for images to be rendered correctly. The measurements were made using a laser interferometer The cooling and reheating process is repeated four times over a six week period. Due to the large size of the vacuum chamber (7,6000 cubic feet), it takes a few days for the liquid helium to cool the chamber to 25 K Full testing of all 18 mirrors is expected to be completed by mid 2011. JWST compared to Hubble Maureen Petterson, Cryogenics, Spring 2010 First Bose-Einstein Condensation of Strontium •November 2009 • Achieved by scientists from the Institute of Quantum Optics and Quantum Information (IQOQI) •Key: Used 84Sr, instead of naturally abundant 86Sr and 88Sr •Precision measurements among the applications Scientist from IQOQI in Innsbruck won the race to produce BoseEinstein condensation of Sr. http://www.physorg.com/news176994672.html Article can be found at http://physics.aps.org/pdf/10.1103/PhysRevLett.103.200401.pdf Reported: (5/27/2009) New Method to Trap Atoms on a Chip “Atom chips” allow for the study of ultra cold atomic gasses at temperatures just above absolute zero. New method involves capturing cold atoms directly onto the atom chips from a room temperature gas of rubidium. Trapping the atoms is the integration of magneto-optical traps, which come from pyramid-shaped structures etched into a silicon wafer. The new technique is fairly simple compared to existing atom trapping methods and is the first observation of direct cold atom trapping from a background vapor inside a micro fabricated structure on an atom chip. Example of Atom Chips CDMS Cryogenic Dark Matter Search Located at Berkeley, there is an experiment that just finished running which uses super-cooled germanium and silicon crystals to try to find WIMPs, Weakly Interacting Massive Particles, which may be the answer to current issues about ‘dark matter.’ As the earth sweeps through the so-called dark matter halo of the Milky Way, the flux of WIMPs is detected by measuring the increase in internal energy of the germanium. Cryogenic Dark Matter Search (CDMS) Corey Mahoney The CDMS scans space for WIMP (weakly interacting massive particle) dark matter from deep underground in Minnesota. A detector of geranium and a detector of silicon are cooled to milliKelvin temperatures using a dilution refrigerator. The extremely low temperatures limit thermal noise which could obscure the necessary phonon signals from particle interactions. Despite being in operation since 2002, on December 17th, 2009, the collaboration working on CDMS announced the possible descoveries of two WIMP dark matter particles. THE EXPERIMENT The Cryogenic Dark Matter Search (CDMS) is a series of experiments designed to directly detect particle dark matter in the form of WIMP’s. Using an array of semiconductor detectors at millikelvin temperatures, CDMS has set the most sensitive limits to date on the interactions of WIMP dark matter with terrestrial materials. The first experiment, CDMSI, was run in a tunnel under the Stanford University campus. The current experiment, CDMSII, is located deep underground in the Soudan Mine in Minnesota. THE DISCOVERY On Dec. 17, 2009, the CDMSII announced that it had detected two pulses which were possible WIMP candidates (one on August 8 and the other on October 27, 2007). Two events were detected that were similar to the properties expected for a Dark Matter particle. However, due to the low number of events, the team could not statistically support these detections as true WIMPs since they may have been false positive from background noise such as neutron collisions. The low number of events leaves things in doubt, though, and the experimenters themselves estimate that there's a 25% chance that the pulses were caused by background radiation, such as those from neutrino collision. Experiments are continuing in an attempt to detect more such pulses, so that it can be determined exactly what their source is. References: -About.com:Physics. CDMS experiment. -Wikipedia.com. Cryogenic Dark Matter Search. -Fermilab THE DETECTORS CDMS detectors are disks of germanium or silicon, cooled to millikelvin temperatures by a dilution refrigerator. The extremely low temperatures are needed to limit thermal noise which would otherwise obscure the phonon signals of particle interactions. Phonon detection is accomplished with superconduction transition edge sensors (TESs) read out by SQUID amplifiers, while ionization signals are read out using an FET amplifier. Close-up of a CDMS detector, made of crystal germanium Pedro J. Mora Cryogenics HW #1 Cryogenic Dark Matter Search • Collaboration amongst universities to detect dark matter by using germanium and silicon detectors detectors cooled to superconductivity. • An increase in resistance (Temperature) would be seen when the dark matter interacts with the detectors CDMSII Detectors using Cryogenic Techniques • Detect WIMPS through weak phonon signals in detector’s crystal • Cooled to 10mK to minimize spurious thermal signals • Testing employs helium3-helium4 dilution refrigerator techniques Magnetism in Gases After cooling lithium atoms to 150 billionth of 1 K above absolute zero , researchers at MIT observed ferromagnetic behavior in the gas, suggesting that a gas of elementary particles doesn’t always need a crystalline structure to exhibit magnetism. There is ongoing research in this topic. Small blob of lithium‐6 gas, chilled ultracold. Method: Researchers used a laser light trap to chill lithium. After the atom’s repulsive forces were increased, ferromagnetism was observed. Sources: http://futurity.org/science‐technology/at‐extremes‐hot‐and‐cold‐act‐oddly‐alike/ http://www.cryogenicsociety.org/magnetism_observed_in_a_gas/#more‐4435 Magnetism observed in Gas? • "Itinerant Ferromagnetism in a Fermi Gas of Ultracold Atoms," Gyu-Boong Jo, Wolfgang Ketterle, et al., Science, Sept. 18, 2009 • A research team at MIT observed ferromagnetic behavior in a gas of lithium-6 isotopes cooled to 150 billionth of 1 Kelvin. • The team trapped the cooled gas in the focus of a infrared laser beam and made several observations which agreed with the theoretical predictions. • If confirmed, this result provides insight into the question of whether or not a crystalline structure is needed for ferromagnetism. • http://web.mit.edu/press/2009/gas-magnetism.html ...
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This note was uploaded on 10/22/2011 for the course PHY 4550 taught by Professor Ihas during the Spring '08 term at University of Florida.

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HW-1-2010-history-2001-09 - Why are safety reliefs...

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