Cobalt

Nevertheless, the gamma radiation emitted from cobalt-60 is used to kill bacteria on fruit and vegetables thus increasing their shelf life. It is often positioned in relation to the television set in a living room and for siesta. The risk in the absence of a nuclear war comes from improper handling (or theft) of medical radiotherapeutic units. Today the couch is invariably linked to both domestic family life and television culture. Some nuclear weapon designs could intentionally increase the amount of Cobalt-60 dispersed as nuclear fallout – this is sometimes called a dirty bomb or cobalt bomb, once predicted by a leading scientist as being capable of wiping out all life on earth. Thus, the couch proved particularly useful because it limits the visibility of the analyst. Cobalt-60 is a risk factor in a nuclear confrontation because neutron emissions will convert iron into this isotope. He justified this with the need to limit the transference between psychoanalyst and analysand.

Ingestion of ⁶⁰Co will lead to incorporation of some cobalt into tissues, which is released very slowly. However when he moved on from hypnosis to stream-of-consciousness discourse as his dominant mode of analysis with the development of the interpretation of dreams, he still held on to the couch. Cobalt-60 is a powerful gamma ray emitter and exposure to ⁶⁰Co is therefore a cancer risk. Freud originally used the couch as a tool to aid his hypnosis of the patient. Cobalt compounds should be handled with care due to cobalt's slight toxicity. The couch is often associated with Freudian psychoanalysis. Powdered cobalt in metal form is a fire hazard. Throughout its history it has often been an object of derision, considered a variety of things from decadent to conformist.

The primary decay products before ⁵⁹Co are element 26 (iron) isotopes and the primary products after are element 28 (nickel) isotopes. Originally it was an elitist piece of furniture and it was not until industrialization that the couch became an indispensable item of furniture in middle and lower class households. The primary decay mode before the most abundant stable isotope, ⁵⁹Co, is electron capture and the primary mode after is beta decay. Three couches would be arranged around a low table and the men would recline while eating (but the women sat in normal chairs). The isotopes of cobalt range in atomic weight from 50 amu (⁵⁰Co) to 73 amu (⁷³Co). In Roman society the couch was found in the dining room, known as the 'triclinum'. This element also has 4 meta states, all of which have half lives less than 15 minutes. The couch was originally an Arabian ruler's throne and has existed since antiquity.

All of the remaining radioactive isotopes have half-lifes that are less than 18 hours and the majority of these have half lives that are less than 1 second. A three-piece suite is composed of three couch pieces (generally, a two- or three-seater and two armchairs). 22 radioisotopes have been characterized with the most stable being ⁶⁰Co with a half-life of 5.2714 years, 57-Co (⁵⁷Co) with a half-life of 271.79 days, and 56-Co (⁵⁶Co) with a half-life of 77.27 days, and 58-Co (⁵⁸Co) with a half life of 70.86 days. A smaller version of the couch which may only comfortably seat two people is more commonly known as a loveseat. Naturally occurring cobalt is composed of 1 stable isotope, 59-Co (⁵⁹Co). There are other types, including two-seater, three-seater, corner and chaise longue. Oxides are antiferromagnetic at low temperature CoO (Neel temperature: 291 K) and Co₃O₄ (Neel temperature: 40 K). Also, to save space, some sofas double as beds (sofa-bed, daybed or futon).

Due to the various oxidation states, there is an abundant number of compounds. Many different types of couch exist: popular types include the divan, the chaise longue, the canapé or the ottoman. It is also produced in the town of Cobalt, Ontario as a byproduct of the silver mining. A typical couch seats two to three people and has an armrest on either side. It is also found in Finland, Azerbaijan, and Kazakhstan. They come in a variety of textiles and in leather. The world's major producers of cobalt are the Democratic Republic of the Congo, mainland China, Zambia, Russia and Australia. Couches are usually to be found in the living room or the lounge.

The main ores of cobalt are cobaltite, erythrite, glaucodot, and skutterudite. A couch, also known as a sofa, settee, lounge or chesterfield is an item of furniture for the comfortable seating of more than one person. Cobalt is usually not mined alone, and tends to be produced as a by-product of nickel and copper mining activities. Cobalt is not found as a free metal and is generally found in the form of ores. Cobalt is a central component of the vitamin cobalamin, or vitamin B-12.

Having 0.13 to 0.30 mg/kg of cobalt in soils markedly improves the health of grazing animals. Cobalt in small amounts is essential to many living organisms, including humans. Some also think the name may derive from Greek kobalos, which means 'mine', and which may have common roots with kobold, goblin, and cobalt. Other sources cite the origin as stemming from silver miners' belief that cobalt had been placed by kobolds who had stolen the silver.

The word cobalt comes from the German kobalt or kobold, meaning evil spirit, the metal being so called by miners, because it was poisonous and troublesome (it polluted and degraded the other mined elements, like nickel). In 1938, John Livingood and Glenn Seaborg discovered cobalt-60. During the 19th century, cobalt blue was produced at the Norwegian Blaafarveværket (70-80 % of world production), led by the Prussian industrialist Benjamin Wegner. He was able to show that cobalt was the source of the blue color in glasses, which previously had been attributed to the bismuth found with cobalt.

The date of discovery varies depending on the source, but is between 1730 and 1737. George Brandt (1694-1768) is credited with the discovery of cobalt. Cobalt was known in ancient times through its compounds, which would color glass a rich blue. The second machine is out beside the walkway into the Centre.

In fact the first machine is on display in the Saskatoon Cancer Centre – look up when entering the lobby. The first ⁶⁰Co therapy machine (the "cobalt bomb") was built and first used in Canada. The ⁶⁰Co source is useful for about 5 years but even after this point is still very radioactive, and so cobalt machines have fallen from favor in the Western world where linacs are common. The metal has the unfortunate habit of producing a fine dust, causing problems with radiation protection.

The ⁶⁰Co source is about 2 cm in diameter and as a result produces a geometric penumbra, making the edge of the radiation field fuzzy. It produces two gamma rays with energies of 1.17 MeV and 1.33 MeV. Cobalt-60 (Co-60 or ⁶⁰Co) is a radioactive metal that is used in radiotherapy. Co-60 is useful as a gamma ray source partially because it can be produced - in known quantity, and very large amounts - by simply exposing natural cobalt to neutrons in a reactor for a given time.

Common oxidation states of cobalt include +2, and +3, though +1 is also seen. Metallic cobalt commonly presents a mixture of two crystallographic structures hcp and fcc with a transition temperature hcp→fcc of 722 K. Cobalt has a relative permeability two thirds that of iron. Cobalt-60, an artificially produced radioactive isotope of cobalt, is an important radioactive tracer and cancer-treatment agent.

Mammals require small amounts of cobalt salts. It is frequently associated with nickel, and both are characteristic ingredients of meteoric iron. The Curie temperature is of 1388 K with 1.6~1.7 Bohr magnetons per atom. Cobalt is a hard ferromagnetic silver-white element.

. Cobalt is a chemical element in the periodic table that has the symbol Co and atomic number 27. London celebrates 50 years of Cobalt-60 Radiotherapy. WebElements.com – Cobalt.

National Pollutant Inventory - Cobalt fact sheet. Cobalt is the name of a current line of cars from Chevrolet. Los Alamos National Laboratory - Cobalt. It is used in industrial radiography to detect structural flaws in metal parts.

It is used in radiation treatment of foods for sterilization (cold pasteurization). It is used in radiotherapy. Cobalt-60 has multiple uses as a gamma ray source: