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A gas explosion in a residential area of Rosario, the third-largest city in Argentina, occurred on August 6, 2013. It was caused by a large gas leak; a nearby building collapsed, and others were at high risk of structural failure. Twenty-two people died, and sixty were injured. Several organizations helped secure the area, search for survivors and aid people who lost their homes. Shortly after the explosion, the time needed for reconstruction was estimated at six months.
The provincial judiciary launched an investigation into the cause of the explosion. Primary suspects were Litoral Gas (the natural-gas provider for Rosario) and an employee who carried out maintenance work at the building that day. Several public figures sent condolences, and most of the candidates for the 2013 primary elections suspended their political campaigns. (Full article...)
Soldering is a process in which two or more items (usually metal) are joined together by melting and putting a filler metal (solder) into the joint, the filler metal having a lower melting point than the adjoining metal. Soldering differs from welding in that soldering does not involve melting the work pieces. In brazing, the filler metal melts at a higher temperature, but the work piece metal does not melt. In the past, nearly all solders contained lead, but environmental and health concerns have increasingly dictated use of lead-free alloys for electronics and plumbing purposes.
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The Castaing machine is a device used to add lettering and decoration to the edge of a coin. Such lettering was necessitated by counterfeiting and edge clipping, which was a common problem resulting from the uneven and irregular hammered coinage. When Aubin Olivier introduced milled coinage to France, he also developed a method of marking the edges with lettering which would make it possible to detect if metal had been shaved from the edge. This method involved using a collar, into which the metal flowed from the pressure of the press. This technique was slower and more costly than later methods. France abandoned milled coinage in favour of hammering in 1585.
England experimented briefly with milled coinage, but it wasn't until Peter Blondeau brought his method of minting coins there in the mid-seventeenth century that such coinage began in earnest in that country. Blondeau also invented a different method of marking the edge, which was, according to him, faster and less costly than the method pioneered by Olivier. Though Blondeau's exact method was secretive, numismatists have asserted that it likely resembled the later device invented by Jean Castaing. Castaing's machine marked the edges by means of two steel rulers, which, when a coinage blank was forced between them, imprinted legends or designs on its edge. Castaing's device found favour in France, and it was eventually adopted in other nations, including Britain and the United States, but it was eventually phased out by mechanised minting techniques. (Full article...)
Birdsill Holly Jr. (November 8, 1820 – April 27, 1894) was an American mechanical engineer and inventor of water hydraulics devices. He is known for inventing mechanical devices that improved city water systems and patented an improved fire hydrant that is similar to those used currently for firefighting. Holly was a co-inventor of the Silsby steam fire engine. He founded the Holly Manufacturing Company that developed into the larger Holly Steam Combination Company that distributed heat from a central station and developed commercial district heating for cities in the United States and Canada. (Full article...)
Edmundo Gómez Moreno (born 17 February 1991), better known by his stage name Raymix, is a Mexican musician and aerospace engineer. Nicknamed El Rey de la Electrocumbia ("The King of Electrocumbia"), Raymix started his music career in the early 2010s, when he joined a trance project called Light & Wave with two other Mexican musicians. Their song "Feeling the City" was featured on the Armin van Buuren radio show A State of Trance. In 2013, Raymix was invited to work in a NASA educative internship, where he helped to develop a satellite.
The Avrocar S/N 58-7055 (marked AV-7055) on its rollout.
The Avro Canada VZ-9 Avrocar was a VTOL aircraft developed by Avro Canada as part of a secret U.S. military project carried out in the early years of the Cold War. The Avrocar intended to exploit the Coandă effect to provide lift and thrust from a single "turborotor" blowing exhaust out of the rim of the disk-shaped aircraft. In the air, it would have resembled a flying saucer.
Originally designed as a fighter-like aircraft capable of very high speeds and altitudes, the project was repeatedly scaled back over time and the U.S. Air Force eventually abandoned it. Development was then taken up by the U.S. Army for a tactical combat aircraft requirement, a sort of high-performance helicopter. In flight testing, the Avrocar proved to have unresolved thrust and stability problems that limited it to a degraded, low-performance flight envelope; subsequently, the project was cancelled in September 1961. (Full article...)
Little Boy was developed by Lieutenant CommanderFrancis Birch's group at the Manhattan Project's Los Alamos Laboratory during World War II, a reworking of their abandoned Thin Man nuclear bomb. Like Thin Man, it was a gun-type fission weapon. It derived its explosive power from the nuclear fission of uranium-235, whereas Thin Man was based on fission of plutonium-239. Fission was accomplished by shooting a hollow cylinder (the "bullet") onto a solid cylinder of the same material (the "target") by means of a charge of nitrocellulose propellant powder. Little Boy contained 64 kilograms (141 lb) of highly enriched uranium, although less than a kilogram underwent nuclear fission. Its components were fabricated at three different plants so that no one would have a copy of the complete design. Unlike the implosion design, which required sophisticated coordination of shaped explosive charges, the gun-type design was considered almost certain to work so it was never tested before its first use at Hiroshima. (Full article...)
Project Alberta was formed in March 1945, and consisted of 51 United States Army, Navy, and civilian personnel, including one British scientist. Its mission was three-fold. It first had to design a bomb shape for delivery by air, then procure and assemble it. It supported the ballistic testing work at Wendover Army Air Field, Utah, conducted by the 216th Army Air Forces Base Unit (Project W-47), and the modification of B-29s to carry the bombs (Project Silverplate). After completion of its development and training missions, Project Alberta was attached to the 509th Composite Group at North Field, Tinian, where it prepared facilities, assembled and loaded the weapons, and participated in their use. (Full article...)
Genetic engineering, also called genetic modification or genetic manipulation, is the modification and manipulation of an organism's genes using technology. It is a set of technologies used to change the genetic makeup of cells, including the transfer of genes within and across species boundaries to produce improved or novel organisms. New DNA is obtained by either isolating and copying the genetic material of interest using recombinant DNA methods or by artificially synthesising the DNA. A construct is usually created and used to insert this DNA into the host organism. The first recombinant DNA molecule was made by Paul Berg in 1972 by combining DNA from the monkey virus SV40 with the lambda virus. As well as inserting genes, the process can be used to remove, or "knock out", genes. The new DNA can be inserted randomly, or targeted to a specific part of the genome.
An organism that is generated through genetic engineering is considered to be genetically modified (GM) and the resulting entity is a genetically modified organism (GMO). The first GMO was a bacterium generated by Herbert Boyer and Stanley Cohen in 1973. Rudolf Jaenisch created the first GM animal when he inserted foreign DNA into a mouse in 1974. The first company to focus on genetic engineering, Genentech, was founded in 1976 and started the production of human proteins. Genetically engineered human insulin was produced in 1978 and insulin-producing bacteria were commercialised in 1982. Genetically modified food has been sold since 1994, with the release of the Flavr Savr tomato. The Flavr Savr was engineered to have a longer shelf life, but most current GM crops are modified to increase resistance to insects and herbicides. GloFish, the first GMO designed as a pet, was sold in the United States in December 2003. In 2016 salmon modified with a growth hormone were sold. (Full article...)
Nichols remained with the Manhattan Project after the war until it was taken over by the Atomic Energy Commission in 1947. He was the military liaison officer with the Atomic Energy Commission from 1946 to 1947. After briefly teaching at the United States Military Academy at West Point, he was promoted to major general and became chief of the Armed Forces Special Weapons Project, responsible for the military aspects of atomic weapons, including logistics, handling and training. He was deputy director for the Atomic Energy Matters, Plans and Operations Division of the Army's general staff, and was the senior Army member of the military liaison committee that worked with the Atomic Energy Commission. (Full article...)
Meticulous naval inventories show that HMS Beagle carried a total of at least 34 recorded chronometers on its three main survey voyages from 1826 to 1843, and 22 on the second voyage with Darwin on board, when they had a dedicated cabin. Some were Navy property and others were on loan from the manufacturers, as well as six on the second voyage owned by the captain, Robert FitzRoy. Both the two known survivors from the second voyage are owned by the British Museum (the second is registration No. CAI.1743). (Full article...)
The Churchill Machine Tool Company Limited began as the manufacturing subsidiary of the machine tool importers Charles Churchill & Company Limited founded in the early 1900s by US-born Charles Churchill (1837–1916). Created out of the personal bankruptcy of Charles Churchill, the company developed to become one of the largest British importers of machine tools from the United States and a major manufacturer of such tools, initially under licence and later of its own development.
The original business importing American machine tools into Britain began with Charles Churchill as sole proprietor and later as a partnership with two others. It became a limited company in 1889. In 1906 a separate company, The Churchill Machine Tool Co Ltd, was established with the purpose of adapting tools imported by Charles Churchill & Co. The former expanded, producing American tools under licence and then manufactured tools of its own design, in particular precision surface grinders and similar engineering machinery. In 1918 The Churchill Machine Tool Co relocated its factories onto a single site at Broadheath, near Altrincham. (Full article...)
Image 5A drawing for a steam locomotive. Engineering is applied to design, with emphasis on function and the utilization of mathematics and science. (from Engineering)
Image 6The application of the steam engine allowed coke to be substituted for charcoal in iron making, lowering the cost of iron, which provided engineers with a new material for building bridges. This bridge was made of cast iron, which was soon displaced by less brittle wrought iron as a structural material. (from Engineering)
Image 8Design of a turbine requires collaboration of engineers from many fields, as the system involves mechanical, electro-magnetic and chemical processes. The blades, rotor and stator as well as the steam cycle all need to be carefully designed and optimized. (from Engineering)
Image 9Archimedes regarded as one of the leading scientists in classical antiquity. (from Engineer)
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