Raymond Davis Jr.
Raymond "Ray" Davis Jr. was an American chemist and physicist. He is best known as the leader of the Homestake experiment in the 1960s-1980s, the first experiment to detect neutrinos emitted from the Sun. Davis was born in Washington, D. C. where his father was a photographer for the National Bureau of Standards. He spent several years as a choirboy to please his mother, he enjoyed attending the concerts at the Watergate before air traffic was loud enough to drown out the music. His brother Warren, 14 months younger than he, was his constant companion in boyhood, he received his B. S. from the University of Maryland in 1938 in chemistry, part of the University of Maryland College of Computer and Natural Sciences. He received a master's degree from that school and a Ph. D. from Yale University in physical chemistry in 1942. Davis spent most of the war years at Dugway Proving Ground, Utah observing the results of chemical weapons tests and exploring the Great Salt Lake basin for evidence of its predecessor, Lake Bonneville.
Upon his discharge from the army in 1946, Davis went to work at Monsanto's Mound Laboratory, in Miamisburg, doing applied radiochemistry of interest to the United States Atomic Energy Commission. In 1948, he joined Brookhaven National Laboratory, dedicated to finding peaceful uses for nuclear power. Davis reports that he was asked "to find something interesting to work on," and dedicated his career to the study of neutrinos, particles, predicted to explain the process of beta decay, but whose separate existence had not been confirmed. Davis investigated the detection of neutrinos by beta decay, the process by which a neutrino brings enough energy to a nucleus to make certain stable isotopes into radioactive ones. Since the rate for this process is low, the number of radioactive atoms created in neutrino experiments is small, Davis began investigating the rates of processes other than beta decay that would mimic the signal of neutrinos. Using barrels and tanks of carbon tetrachloride as detectors, Davis characterized the rate of the production of argon-37 as a function of altitude and as a function of depth underground.
He deployed a detector containing chlorine atoms at the Brookhaven Reactor in 1954 and one of the reactors at Savannah River. These experiments failed to detect a surplus of radioactive argon when the reactors were operating over when the reactors were shut down, this was taken as the first experimental evidence that neutrinos causing the chlorine reaction, antineutrinos produced in reactors, were distinct. Detecting neutrinos proved more difficult than not detecting antineutrinos. Davis was the lead scientist behind the Homestake Experiment, the large-scale radiochemical neutrino detector which first detected evidence of neutrinos from the sun, he shared the Nobel Prize in Physics in 2002 with Japanese physicist Masatoshi Koshiba and Italian Riccardo Giacconi for pioneering contributions to astrophysics, in particular for the detection of cosmic neutrinos, looking at the solar neutrino problem in the Homestake Experiment. He was 88 years old. Davis met his wife Anna Torrey at Brookhaven and together they built a 21-foot wooden sailboat, the Halcyon.
They lived in the same house in Blue Point, New York for over 50 years. He died in New York from Alzheimer's Disease. Comstock Prize in Physics of the National Academy of Sciences Tom W. Bonner Prize of the American Physical Society W. K. H. Panofsky Prize of the American Physical Society Beatrice M. Tinsley Prize of the American Astronomical Society George Ellery Hale Prize of the American Astronomical Society Wolf Prize in Physics National Medal of Science Nobel Prize in Physics Benjamin Franklin Medal Davis, Raymond Jr.. "Attempt to detect the Antineutrinos from a Nuclear Reactor by the 37Cl 37Ar Reaction". Physical Review. 97: 766. Bibcode:1955PhRv...97..766D. Doi:10.1103/PhysRev.97.766. – Non-detection of antineutrinos with chlorine Davis, Raymond Jr.. "Solar Neutrinos II, Experimental". Physical Review Letters. 12: 303. Bibcode:1964PhRvL..12..303D. Doi:10.1103/PhysRevLett.12.303. – Proposal for Homestake Experiment Cleveland, B. T.. "Measurement of the solar electron neutrino flux with the Homestake chlorine detector".
Astrophysical Journal. 496: 505–526. Bibcode:1998ApJ...496..505C. doi:10.1086/305343. – final results of Homestake Experiment Davis, R. Jr. & D. S. Harmer. "Solar Neutrinos", Brookhaven National Laboratory. Davis, R. Jr. "Search for Neutrinos from the Sun", Brookhaven National Laboratory, United States Department of Energy. Davis, R. Jr. & J. C. Evans Jr. "Report on the Brookhaven Solar Neutrino Experiment", Brookhaven National Laboratory. Davis, R. Jr. Evans, J. C. & B. T. Cleveland. "Solar Neutrino Problem", Brookhaven National Laboratory. Davis, R. Jr. Cleveland, B. T. & J. K. Rowley. "Variations in the Solar Neutrino Flux", Department of Astronomy and Astrophysics at University of Pennsylvania, Los Alamos National Laboratory, Brookhaven National Laboratory. Raymond Davis Jr. biography at the Nobel Foundation Raymond Davis Jr. Brookhaven National Lab Web site Neutrino web at PBS NOVA The Raymond Davis Scholarship Society for Imaging Science and Technology
In structural geology, an anticline is a type of fold, an arch-like shape and has its oldest beds at its core. A typical anticline is convex up in which the hinge or crest is the location where the curvature is greatest, the limbs are the sides of the fold that dip away from the hinge. Anticlines can be recognized and differentiated from antiforms by a sequence of rock layers that become progressively older toward the center of the fold. Therefore, if age relationships between various rock strata are unknown, the term antiform should be used; the progressing age of the rock strata towards the core and uplifted center, are the trademark indications for evidence of anticlines on a geologic map. These formations occur because anticlinal ridges develop above thrust faults during crustal deformations; the uplifted core of the fold causes compression of strata that preferentially erodes to a deeper stratigraphic level relative to the topographically lower flanks. Motion along the fault including both shortening and extension of tectonic plates also deforms strata near the fault.
This overturned fold. An antiform can be used to describe any fold, convex up, it is the relative ages of the rock strata. The hinge of an anticline refers to the location where the curvature is greatest called the crest; the hinge is the highest point on a stratum along the top of the fold. The culmination refers to the highest point along any geologic structure; the limbs are the sides of the fold. The inflection point is the area on the limbs; the axial surface is an imaginary plane connecting the hinge of each layer of rock stratum through the cross section of an anticline. If the axial surface is vertical and the angles on each side of the fold are equivalent the anticline is symmetrical. If the axial plane is tilted or offset the anticline is asymmetrical. An anticline, cylindrical has a well-defined axial surface, whereas non-cylindrical anticlines are too complex to have a single axial plane. An overturned anticline is an asymmetrical anticline with a limb, tilted beyond perpendicular, so that the beds in that limb have flipped over and may dip in the same direction on both sides of the axial plane.
If the angle between the limbs is large the fold is an "open" fold, but if the angle between the limbs is small the fold is a "tight" fold. If an anticline plunges, it will form Vs on a geologic map view that point in the direction of plunge. A plunging anticline has a hinge, not parallel to the earth's surface. All anticlines and synclines have some degree of plunge. Periclinal folds are a type of anticlines that have a well-defined, but curved hinge line and are doubly plunging and thus elongate domes. Folds in which the limbs dip toward the hinge and display a more U-like shape are called synclines, they flank the sides of anticlines and display opposite characteristics. A syncline's oldest rock strata are in its outer limbs. A monocline is a bend in the strata resulting in a local steepening in only one direction of dip. Monoclines have the shape of a carpet draped over a stairstep. An anticline, more eroded in the center is called a breached or scalped anticline. Breached anticlines can become incised by stream erosion.
A structure that plunges in all directions to form a circular or elongate structure is a dome. Domes may be created via diapirism from underlying magmatic intrusions or upwardly mobile, mechanically ductile material such as rock salt and shale that cause deformations and uplift in the surface rock; the Richat Structure of the Sahara is considered a dome, laid bare by erosion. An anticline which plunges at both ends is termed a doubly plunging anticline, may be formed from multiple deformations, or superposition of two sets of folds, it may be related to the geometry of the underlying detachment fault and the varying amount of displacement along the surface of that detachment fault. An anticlinorium is a large anticline. Examples include the Late Jurassic to Early Cretaceous Purcell Anticlinorium in British Columbia and the Blue Ridge anticlinorium of northern Virginia and Maryland in the Appalachians, or the Nittany Valley in central Pennsylvania. Anticlines are developed above thrust faults, so any small compression and motion within the inner crust can have large effects on the upper rock stratum.
Stresses developed during mountain building or during other tectonic processes can warp or bend bedding and foliation. The more the underlying fault is tectonically uplifted, the more the strata will be deformed and must adapt to new shapes; the shape formed will be dependent on the properties and cohesion of the different types of rock within each layer. During the formation of flexural-slip folds, the different rock layers form parallel-slip folds to accommodate for buckling. A good way to visualize how the multiple layers are manipulated, is to bend a deck of cards and to imagine each card as a layer of rock stratum; the amount of slip on each side of the anticline increases from the hinge to the inflection point. Passive-flow folds form when the rock is so soft that it behaves like weak plastic and flows. In this process different parts of the rock body move at different rates causing shear stress to shift from layer to layer. There is no mec
Gold mining is the resource extraction of gold by mining. It is impossible to know the exact date that humans first began to mine gold, but some of the oldest known gold artifacts were found in the Varna Necropolis in Bulgaria; the graves of the necropolis were built between 4700 and 4200 BC, indicating that gold mining could be at least 7000 years old. A group of German and Georgian archaeologists claims the Sakdrisi site in southern Georgia, dating to the 3rd or 4th millennium BC, may be the world's oldest known gold mine. Bronze age gold objects are plentiful in Ireland and Spain, there are several well known possible sources. Romans used hydraulic mining methods, such as hushing and ground sluicing on a large scale to extract gold from extensive alluvial deposits, such as those at Las Medulas. Mining was under the control of the state but the mines may have been leased to civilian contractors some time later; the gold served as the primary medium of exchange within the empire, was an important motive in the Roman invasion of Britain by Claudius in the first century AD, although there is only one known Roman gold mine at Dolaucothi in west Wales.
Gold was a prime motivation for the campaign in Dacia when the Romans invaded Transylvania in what is now modern Romania in the second century AD. The legions were led by the emperor Trajan, their exploits are shown on Trajan's Column in Rome and the several reproductions of the column elsewhere. Under the Eastern Roman Empire Emperor Justinian's rule, gold was mined in the Balkans, Armenia and Nubia. In the area of the Kolar Gold Fields in Bangarpet Taluk, Kolar District of Karnataka state, gold was first mined prior to the 2nd and 3rd century AD by digging small pits; the Champion reef at the Kolar gold fields was mined to a depth of 50 metres during the Gupta period in the fifth century AD. During the Chola period in the 9th and 10th century AD, the scale of the operation grew; the metal continued to be mined by the eleventh century kings of South India, the Vijayanagara Empire from 1336 to 1560, by Tipu Sultan, the king of Mysore state and the British. It is estimated; the mining of the Hungarian deposit around Kremnica was the largest of the Medieval period in Europe.
During the 19th century, numerous gold rushes in remote regions around the globe caused large migrations of miners, such as the California Gold Rush of 1849, the Victorian Gold Rush, the Klondike Gold Rush. The discovery of gold in the Witwatersrand led to the Second Boer War and the founding of South Africa; the Carlin Trend of Nevada, U. S. was discovered in 1961. Official estimates indicate that total world gold production since the beginning of civilization has been around 6,109,928,000 troy ounces and total gold production in Nevada is 2.5% of that, ranking Nevada as one of the Earth's primary gold producing regions. As of 2017, the world's largest gold producer by far was China with 429.4 tonnes in that year. The second-largest producer, mined 289.0 tonnes in the same year, followed by Russia with 273 tonnes. Despite the decreasing gold content of ores, the production is increasing; this can be achieved with industrial installations, new process, like hydrometallurgy. Placer mining is the technique.
Placer deposits are composed of loose material that makes tunneling difficult, so most means of extracting it involve the use of water or dredging. Gold panning is a manual technique of separating gold from other materials. Wide, shallow pans are filled with gravel that may contain gold; the pan is shaken, sorting the gold from the gravel and other material. As gold is much denser than rock, it settles to the bottom of the pan; the panning material is removed from stream beds at the inside turn in the stream, or from the bedrock shelf of the stream, where the density of gold allows it to concentrate, a type called placer deposits. Gold panning is the easiest and quickest technique for searching for gold, but is not commercially viable for extracting gold from large deposits, except where labor costs are low or gold traces are substantial. Panning is marketed as a tourist attraction on former gold fields. Before large production methods are used, a new source must be identified and panning is useful to identify placer gold deposits to be evaluated for commercial viability.
Using a sluice box to extract gold from placer deposits has long been a common practice in prospecting and small-scale mining. A sluice box is a man made channel with riffles set in the bottom; the riffles are designed to create dead zones in the current to allow gold to drop out of suspension. The box is placed in the stream to channel water flow. Gold-bearing material is placed at the top of the box; the material is carried by the current through the volt where gold and other dense material settles out behind the riffles. Less dense material flows out of the box as tailings. Larger commercial placer mining operations employ screening plants, or trommels, to remove the larger alluvial materials such as boulders and gravel, before concentrating the remainder in a sluice box or jig plant; these operations include diesel powered, earth moving equipment, including excavators, wheel loaders, rock trucks. Although this method has been replaced by modern m
A fireless locomotive is a type of locomotive which uses reciprocating engines powered from a reservoir of compressed air or steam, filled at intervals from an external source. They offer advantages over conventional steam locomotives of lower cost per unit and decreased risk from fire or boiler explosion. Typical usage was in industrial switching where a conventional locomotive was too noxious or risky, such as in a mine or a food or chemical factory, they were displaced by diesel and battery electric locomotives fitted with protective appliances. An early application of the fireless locomotive was to street tramways in the USA. Emile Lamm developed two types of fireless locomotive, one using ammonia and the other using stored steam. Lamm founded two companies, Ammonia & Thermo-Specific Propelling Company of America in 1872 and Lamm Fireless Engine Company in 1874. Lamm's fireless engines were popular, both in the USA and in France, but were soon displaced by electric trams; the French locomotives were built in association under the name Lamm & Francq.
The fireless system gained a new lease of life for industrial shunting locomotives. Any factory which possessed a stationary boiler could use it to charge a fireless steam locomotive for internal shunting operations. Fireless shunting locomotives became popular in Germany and some remained in service into the 1960s. Fireless industrial shunters were of the 0-4-0 or 0-6-0 wheel arrangement but some 0-8-0s were built, by companies including Heisler. Pennsylvania Power and Light "D", in the gallery below, is an example of an 0-8-0 fireless Heisler locomotive; the Swiss company, DLM, was trying to promote the fireless steam locomotive as an environmentally-friendly alternative to the diesel locomotive for shunting. DLM claims that diesel shunters spend 75% of their working time with the engine idling. A fireless steam locomotive is similar to a conventional steam locomotive, but has a reservoir, known as a steam accumulator, instead of a boiler; this reservoir is charged with superheated water under pressure from a stationary boiler.
The engine works like a conventional steam engine using the high pressure steam above the water in the accumulator. As the steam is used and pressure drops, the superheated water boils; the locomotive can work like this until the pressure has dropped to a minimum useful level or the water runs out, after which it must be recharged. European fireless steam locomotives have the cylinders at the back, while American ones have the cylinders at the front, as in a conventional locomotive. Major builders of fireless steam locomotives in the UK included Andrew Barclay and W. G. Bagnall; the first locomotive to run on compressed air was built in 1890, by 1895, the basic principles of efficient compressed air engines had been developed. A important engineering breakthrough was the development of the reducing and stop valve which maintains a uniform pressure of air to the engine as the pressure in the storage tank reduces with use. Compressed air locomotives have been used for many years in mines, but have been used on tramways.
Several hybrid locomotives have been built that have either used a fire for part of the time, e.g. Fowler's Ghost of London's Metropolitan in 1861, or have used a fire to superheat stored steam, such as the Receiver Locomotives built by Sentinel Waggon Works. None has been a success. Most fireless locomotives have been of 0-4-0 or 0-6-0 wheel arrangement but there have been some 0-8-0 and a few 0-10-0; some 600 mm gauge 0-10-0 fireless locomotives from the German company Henschel were used in the construction of the Baghdad Railway to avoid the risk of carbon monoxide poisoning during the boring of tunnels. Another German company, built some articulated fireless steam locomotives with a cab at each end. Only one of the bogies was powered, making the wheel arrangement B-2. Steam traction became obsolete in the 1940s and was replaced by diesel or electric traction. However, fireless steam has its merits where there is an abundant cheap source of steam, such as in industrial sites, at thermal power stations or refuse incineration plants, where fireless steam locomotives are used for shunting at low cost.
As they do not emit any exhaust except steam, they can shunt into buildings without endangering the workforce with noxious fumes. Considering that shunting locomotives are working for only about 10% of the time, 90% waiting for work. A well insulated modern steam accumulator can preserve pressure over many hours, thus the operating cost of a fireless steam shunter can be far less than that of a comparable diesel. Fireless locomotives are safer to operate than conventional steam locomotives, aside from the elimination of ignition hazards; the primary cause of a locomotive boiler explosion is the depletion of boiler water, through inattention or excessive use, exposing the crown sheet directly to the flames of the firebox without the cooling effect of the water covering, weakening it to the point of failure. A fireless locomotive eliminates this danger—if it runs out of sufficient water, it ceases to move—although precautions must be taken as with any other pressure vessel. Furthermore, they did not require careful monitoring of water levels and bo
The Denver Mint is a branch of the United States Mint that struck its first coins on February 1, 1906. The mint is still operating and producing coins for circulation, as well as mint sets and commemorative coins. Coins produced at the Denver Mint bear a D mint mark; the Denver Mint is the single largest producer of coins in the world.. The predecessors of the Denver Mint were the men of Clark and Company. During the Pikes Peak Gold Rush, they coined gold dust brought from the gold fields by the miners. In 1858, Austin M. Clark, Milton E. Clark and Emanuel Henry Gruber founded a brokerage firm in Leavenworth and established an office in Denver at the beginning of the Colorado Gold Rush. Desiring to save on shipping and insurance costs associated with shipping gold back east, the firm opened a private mint. On 25 July 1860, the mint opened in a two-story brick building on the corner of Market and 16th Streets, minting $10 gold pieces at the rate of "fifteen or twenty coins a minute". "On the face is a representation of the peak, its base surrounded by a forest of timber and'Pikes Peak Gold' encircling the summit.
Under its base is the word'Denver', beneath it'Ten D.'. On the reverse is the American Eagle encircled by the name of the firm'Clark, Gruber & Co.', beneath the date,'1860'."A $20 gold coin was added, "the weight will be greater, but the value the same as the United States coin of like denomination". A $5 and a $2.5 gold coin were added, with production reaching $18,000 per week. On the front was the "head of the Goddess of Liberty surrounded by thirteen stars, with "Clark & Company" in the tiara. "Pikes's Peak Gold, Denver" was on the other side, with "5D." or "2 1/2 D."In the three years of operation, they minted $594,305 worth of Pike's Peak Gold in the form of gold coins. Additionally, they purchased 77,000 troy ounces of raw gold, shipped "large amounts of dust" to the Philadelphia Mint; the building and minting equipment was formally bought by the US Treasury in April 1863. Clark, Gruber & Co. remained a bank until bought by the First National Bank of Denver in 1865. Established by an Act of Congress on April 21, 1862, the United States Mint at Denver opened for business in late 1863 as a United States Assay Office.
Operations began in the facilities of Clark and Company, located at 16th and Market Streets and acquired by the government for $25,000, which it was able to print off at the location. Unlike Clark and Company, the Denver plant performed no coinage of gold as first intended. One reason given by the Director of the Mint for the lack of coinage at Denver was, "…the hostility of the Indian tribes along the routes, doubtless instigated by rebel emissaries and bad white men." Gold and nuggets brought there by miners from the surrounding area were accepted by the Assay Office for melting and stamping of cast gold bars. The bars were returned to the depositors as imparted bars stamped with the weight and fineness of the gold. Most of the gold came from the rich beds of placer gold found in the streams and first discovered in 1858, the same year Denver was founded; when the supply of gold was exhausted from the streams, the emphasis turned to lode mining, uncovering veins of ore with a high percentage of gold and silver.
By 1859, the yearly value of the gold and silver deposited at the Assay Office was over $5.6 million. During its early years as an Assay Office, the Denver plant was the city's most substantial structure; the United States Treasury did not expand its smelting and refining operations at the same rate as the discovery and production of gold. In 1872 a group of businessmen led by Judge Hiram Bond, Joseph Miner and Denver Mayor Joseph E. Bates set up a firm Denver Smelting and Refining Works which built an independent complementary plant which processed ore into ingots which were assayed and stamped by the Denver Mint. There was new hope for branch mint status when Congress provided for the establishment of a mint at Denver for gold and silver coin production; the site for the new mint at West Colfax and Delaware streets was purchased on April 22, 1896, for $60,000. Construction began in 1897. Appropriations to complete and equip the plant were insufficient, the transfer of assay operations to the new building were delayed until September 1, 1904.
Coinage operations began on February 1, 1906, advancing the status of the Denver facility to Branch Mint. In addition, before the new machinery to be used at the Mint was installed for use, it was first sent to the St. Louis Exposition of 1904 for display. Silver coins were minted in Denver for the first time in 1906. During the first year, 167 million coins were produced, including $20 gold coins, $10 gold coins, $5 gold coins, assorted denominations of silver coins; the Denver Mint is mentioned in The Andy Griffith Show episode "A Black Day for Mayberry". The Denver Mint is featured in the 1993 Sylvester Stallone film Cliffhanger, as the production point of the money stolen in the film, the departure point for the plane; the Mint is mentioned in both the title and lyrics of the Jimmy Eat World song "Lucky Denver Mint". The Denver Mint appears anachronistically in the 1870s in the 1967 The Wild Wild West episode "The Night of the Circus of Death". To above, The Mint is anachronistically set in the 1870s in the 1960 Shotgun Slade episode "The Missing Train".
The 1960 episode "Cold Hard Cash" of The Rifleman, set a few ye
War Production Board
The War Production Board was an agency of the United States government that supervised war production during World War II. President Franklin D. Roosevelt established it in January 1942, with Executive Order 9024; the WPB replaced the Office of Production Management. The WPB directed conversion of industries from peacetime work to war needs, allocated scarce materials, established priorities in the distribution of materials and services, prohibited nonessential production, it rationed such commodities as gasoline, heating oil, rubber and plastics. It was dissolved shortly after the defeat of Japan in 1945, was replaced by the Civilian Production Administration in late 1945. In 1942-45, WPB supervised the production of $183 billion worth of weapons and supplies, about 40% of the world output of munitions. Britain, the USSR and other allies produced an additional 30%, while the Axis produced only 30%. One fourth of the US output was warplanes. Meanwhile, the civilian standard of living was about level.
The first chairman of the Board was Donald M. Nelson, who served from 1942 to 1944, he was succeeded by Julius A. Krug; the national WPB constituted the chair, the Secretaries of War and Agriculture, the lieutenant general in charge of War Department procurement, the director of the Office of Price Administration, the Federal Loan Administrator, the chair of the Board of Economic Warfare, the special assistant to the President for the defense aid program. The WPB had advisory, policy-making, progress-reporting divisions; the WPB managed twelve regional offices, operated one hundred twenty field offices throughout the nation. They worked alongside state war production boards, which maintained records on state war production facilities and helped state businesses obtain war contracts and loans; the national WPB's primary task was converting civilian industry to war production. The WPB assigned priorities and allocated scarce materials such as steel and rubber, prohibited nonessential industrial production such as nylons and refrigerators, controlled wages and prices, mobilized the people through patriotic propaganda such as "give your scrap metal and help Oklahoma boys save our way of life."
It initiated events such as scrap metal drives. For example, a national scrap metal drive in October 1942 resulted in an average of eighty-two pounds of scrap per American. WPB order M-9-C related to the conservation of copper, in May 1942 The Film Daily reported that this would apply to the production of new motion picture sound and projection equipment, but not to the delivery of items produced; the WPB and the nation's factories effected a great turnaround. Military aircraft production, which totaled 6,000 in 1940, jumped to 85,000 in 1943. Factories that made silk ribbons now produced parachutes, automobile factories built tanks, typewriter companies converted to machine guns, undergarment manufacturers sewed mosquito netting, a roller coaster manufacturer converted to the production of bomber repair platforms; the WPB ensured that each factory received the materials it needed to produce the most war goods in the shortest time. Without American production the Allies could never have won the war.
From 1942 to 1945 the WPB directed a total production of $185 billion worth of armaments and supplies. At war's end, most production restrictions were lifted, the WPB was abolished on November 3, 1945, with its remaining functions transferred to the Civilian Production Administration. William Beverly Murphy, president and CEO of Campbell Soup Company Charles E. Wilson, President of General Electric T. S. Fitch, President and CEO of Washington Steel Corporation Faustin Johnson Solon, a chairman of the War Production Board, representing Owens-Illinois Glass Company Irving Brown, representing the American Federation of Labor Executive Order 9638 created the Civilian Production Administration and terminated the War Production Board on October 4, 1945; the Civilian Production Board was consolidated with other agencies to form the Office of Temporary Controls—an agency in the Office for Emergency Management of the Executive Office of the President. The latter had been established pursuant to the Reorganization Act of 1939.
The Executive Order provided a Temporary Controls Administrator, appointed by the President, to head the Office of Temporary Controls and vested in him, among other things, the functions of the Price Administrator. Studies in industrial price control by United States Office of Temporary Controls. U. S. Govt. Print. Off. 1947 Problems in price control: legal phases by United States Office of Temporary Controls. U. S. Govt. Print. Off. 1947 Problems in price control by United States Office of Temporary Controls. U. S. Govt. Print. Off. 1948 The beginnings of OPA by United States Office of Temporary Controls. Office of Temporary Controls, Office of Price Administration, 1947 Guaranteed wages by United States Office of Temporary Controls. U. S. Govt. Print. Off. 1947 Herman, Arthur. Freedom's Forge: How American Business Produced Victory in World War II. New York: Random House. ISBN 978-1-4000-6964-4. Catton, Bruce; the War Lords of Washington. New York: Harcourt, Brace, & Co. 1948. War Production Board
Greenschists are metamorphic rocks that formed under the lowest temperatures and pressures produced by regional metamorphism 300–450 °C and 2–10 kilobars. Greenschists have an abundance of green minerals such as chlorite and epidote, platy minerals such as muscovite and platy serpentine; the platiness have schistosity. Other common minerals include quartz, talc, carbonate minerals and amphibole. Greenschist is a general field petrologic term for altered mafic volcanic rock. In Europe, the term prasinite is sometimes used. A greenstone is sometimes a greenschist but can be rock types without any schistosity metabasalt; the green is due to abundant green chlorite and epidote minerals that dominate the rock. However, basalts may remain quite black if primary pyroxene does not revert to chlorite or actinolite. To qualify for the name a rock must exhibit schistosity or some foliation or layering; the rock is derived from basalt, gabbro or similar rocks containing sodium-rich plagioclase feldspar, chlorite and quartz.
Greenschist, as a rock type, is defined by the presence of the minerals chlorite and actinolite and may contain albite or epidote. Greenschist has a lepidoblastic, nematoblastic or schistose texture defined by chlorite and actinolite. Greenschists have some foliation resulting in mineral alignment of chlorite and actinolite. Grain size is coarse, due to the mineral assemblage. Chlorite and to a lesser extent actinolite exhibit small, flat or acicular crystal habits. Greenschist facies is determined by the particular temperature and pressure conditions required to metamorphose basalt to form the typical greenschist facies minerals chlorite and albite. Greenschist facies results from moderate pressure metamorphism. Metamorphic conditions which create typical greenschist facies assemblages are called the Barrovian Facies Sequence, the lower-pressure Abukuma Facies Series. Temperatures of 400 to 500 °C and depths of about 8 to 50 kilometres are the typical envelope of greenschist facies rocks; the equilibrium mineral assemblage of rocks subjected to greenschist facies conditions depends on primary rock composition.
Basalt: chlorite + actinolite + albite +/- epidote Ultramafic: chlorite + serpentine +/- talc +/- tremolite +/- diopside +/- brucite Pelites: quartz +/- albite +/- k-feldspar +/- chlorite, garnet, pyrophyllite +/- graphite Calc-silicates: calcite +/- dolomite +/- quartz +/- micas, wollastonite, etc. In greater detail the greenschist facies is subdivided into subgreenschist and upper greenschist. Lower temperatures are transitional with and overlap the prehnite-pumpellyite facies and higher temperatures overlap with and include sub-amphibolite facies. If burial continues along Barrovian Sequence metamorphic trajectories, greenschist facies gives rise to amphibolite facies assemblages, dominated by amphibole and to granulite facies. Lower pressure contact metamorphism produces albite-epidote hornfels while higher pressures at great depth produces eclogite. Oceanic basalts in the vicinity of mid-ocean ridges exhibit sub-greenschist alteration; the greenstone belts of the various archean cratons are altered to the greenschist facies.
These ancient rocks are noted as host rocks for a variety of ore deposits in Australia and Canada. Greenschist-like rocks can be formed under blueschist facies conditions if the original rock contains enough magnesium; this explains the scarcity of blueschist preserved from before the Neoproterozoic Era 1000 Ma ago when the Earth's oceanic crust contained more magnesium than today's oceanic crust. In Minoan Crete and blueschist were used to pave streets and courtyards between 1650 and 1600 BC; these rocks were quarried in Agia Pelagia on the north coast of central Crete. Across Europe, greenschist rocks have been used to make axes. Several sites, including Great Langdale in England, have been identified. A form of chlorite schist was popular in prehistoric Native American communities for the production of axes and celts, as well as ornamental items. In the Middle Woodland period, greenschist was one of the many trade items that were part of the Hopewell culture exchange network, sometimes transported over thousands of kilometers.
During the time of the Mississippian culture, the polity of Moundville had some control over the production and distribution of greenschist. The Moundville source has been shown to be from two localities in the Hillabee Formation of central and eastern Alabama. Metamorphism List of rock types List of minerals Pounamu, another type of rock called greenstone Blatt and Robert J. Tracy. Petrology. ISBN 0-7167-2438-3. Gall, Daniel G. and Vincas P. Steponaitis, "Composition and Provenance of Greenstone Artifacts from Moundville," Southeastern Archaeology 20:99–117 ). Steponaitis, Vincas P. Prehistoric Archaeology in the Southeastern United States, 1970–1985. Annual Review of Anthropology, Vol. 15. Pp. 363–404