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67-641: The war effort was already winding down when the first production units arrived in late 1944. A small number were fitted to B-17 Flying Fortress and B-24 Liberator aircraft intended for use in Europe, but none of these arrived in time to see action before the war ended. The system was first used operationally with the B-29 Superfortress in the Pacific Theater starting in May 1945. The addition of

134-475: A polymerisation process. About 80 years later it was realized that heating of styrol starts a chain reaction that produces macromolecules , following the thesis of German organic chemist Hermann Staudinger (1881–1965). This eventually led to the substance receiving its present name, polystyrene. The company I. G. Farben began manufacturing polystyrene in Ludwigshafen , about 1931, hoping it would be

201-462: A "blowing agent", a material that enables the beads to be expanded. Pentane is commonly used as the blowing agent. The beads are added to a continuously agitated reactor with the blowing agent, among other additives, and the blowing agent seeps into pores within each bead. The beads are then expanded using steam. EPS is used for food containers , molded sheets for building insulation , and packing material either as solid blocks formed to accommodate

268-576: A "gold plated" design known as the Universal Bomb Sight, or UBS. Developed by Bell Labs , the UBS was an enormous mechanical computer , about 1,000 pounds (450 kg), that could be provided with any sort of inputs and conditions, and provide a bombing cue. Unlike similar models like the Norden bombsight , the UBS was designed to have little settling time, and would allow maneuvering throughout

335-444: A B-24 bomber and flew for its first tests on 16 June 1943. A series of tests at Westover Field demonstrated that the antenna worked well, but none of the other electronics were reliable. Testing continued until October, when the bomber, S.N 42–40344, was flown to Boca Raton to continue testing in better weather. While the basic system was being tested, consideration was being given to the displays and ballistics computer. This led to

402-563: A US patent for polystyrene foam as an insulation product in 1935 (USA patent number 2,023,204). PS foams also exhibit good damping properties, therefore it is used widely in packaging. The trademark Styrofoam by Dow Chemical Company is informally used (mainly US & Canada) for all foamed polystyrene products, although strictly it should only be used for "extruded closed-cell" polystyrene foams made by Dow Chemicals. Foams are also used for non-weight-bearing architectural structures (such as ornamental pillars ). Expanded polystyrene (EPS)

469-466: A chain of polystyrene, giving a molar mass of 100,000–400,000 g/mol. Each carbon of the backbone has tetrahedral geometry , and those carbons that have a phenyl group (benzene ring) attached are stereogenic . If the backbone were to be laid as a flat elongated zig-zag chain, each phenyl group would be tilted forward or backward compared to the plane of the chain. The relative stereochemical relationship of consecutive phenyl groups determines

536-468: A grey/black color which distinguishes it from standard EPS. Several EPS producers have produced a variety of these increased thermal resistance EPS usage for this product in the UK and EU. Water vapor diffusion resistance ( μ ) of EPS is around 30–70. ICC-ES ( International Code Council Evaluation Service) requires EPS boards used in building construction meet ASTM C578 requirements. One of these requirements

603-402: A heated debate about the proper antenna design for ground mapping systems. Bowen was convinced that the antenna had to be highly accurate in both azimuth and elevation, in order to provide reasonable resolution. Improving resolution over that of H2S would either require larger antennae that would be unwieldy, or decreasing the wavelength of the transmitter beyond the state of the art . Alvarez

670-672: A metallocene catalyst for the polymerisation reaction. Polystyrene is relatively chemically inert. While it is waterproof and resistant to breakdown by many acids and bases, it is easily attacked by many organic solvents (e.g. it dissolves quickly when exposed to acetone ), chlorinated solvents, and aromatic hydrocarbon solvents. Because of its resilience and inertness, it is used for fabricating many objects of commerce. Like other organic compounds, polystyrene burns to give carbon dioxide and water vapor , in addition to other thermal degradation by-products. Polystyrene, being an aromatic hydrocarbon , typically combusts incompletely as indicated by

737-416: A number of means, the phase angle would vary, causing the resulting signal to be focussed in a given direction. Since the antenna didn't have to move in order to scan, this led to the possibility of embedding the antenna in the leading edges of the aircraft wings, or similar solutions. However, such a system would then be subject to changes in the aircraft's attitude, something that H2S addressed by mounting

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804-399: A serious concern. The team moved to a 16 foot (4.9 m) long model with 252 dipoles, mounted in a separate streamlined wing-like enclosure. The width was limited to 16 feet simply because that was the largest wood planer the team could access. Two dipoles were later removed at the request of an industrial partner who preferred to work with round numbers. The new system was mounted to

871-722: A smoke-developed index of less than 450. ICC-ES requires the use of a 15-minute thermal barrier when EPS boards are used inside of a building. According to the EPS-IA ICF organization, the typical density of EPS used for insulated concrete forms ( expanded polystyrene concrete ) is 1.35 to 1.80 pounds per cubic foot (21.6 to 28.8 kg/m ). This is either Type II or Type IX EPS according to ASTM C578. EPS blocks or boards used in building construction are commonly cut using hot wires. Extruded polystyrene foam (XPS) consists of closed cells. It offers improved surface roughness, higher stiffness and reduced thermal conductivity. The density range

938-513: A split via a channel system of gates and runners. EPS is colloquially called "styrofoam" in the Anglosphere , an genericization of Dow Chemical's brand of extruded polystyrene . Sheets of EPS are commonly packaged as rigid panels (common in Europe is a size of 100 cm x 50 cm, usually depending on an intended type of connection and glue techniques, it is, in fact, 99.5 cm x 49.5 cm or 98 cm x 48 cm; less common

1005-496: A sprayed-on coating is necessary to prevent saturation. Oriented polystyrene (OPS) is produced by stretching extruded PS film, improving visibility through the material by reducing haziness and increasing stiffness. This is often used in packaging where the manufacturer would like the consumer to see the enclosed product. Some benefits to OPS are that it is less expensive to produce than other clear plastics such as polypropylene (PP), (PET), and high-impact polystyrene (HIPS), and it

1072-513: A suitable replacement for die-cast zinc in many applications. Success was achieved when they developed a reactor vessel that extruded polystyrene through a heated tube and cutter, producing polystyrene in pellet form. Ray McIntire (1918–1996), a chemical engineer of Dow Chemical, rediscovered a process first patented in early 1930s by Swedish inventor Carl Munters . According to the Science History Institute, "Dow bought

1139-416: A wavelength apart. This doubled the number of elements in a given area, likewise doubling the signal strength while also further reducing the side lobes. What remained was the development of a suitable system for delaying the signal on demand, allowing the direction of the beam to be scanned. The key problem was to change the speed of the signal on demand so the phase could be adjusted. After several concepts,

1206-497: Is 120 x 60 cm; size 4 by 8 ft (1.2 by 2.4 m) or 2 by 8 ft (0.61 by 2.44 m) in the United States). Common thicknesses are from 10 mm to 500 mm. Many customizations, additives, and thin additional external layers on one or both sides are often added to help with various properties. An example of this is lamination with cement board to form a structural insulated panel . Thermal conductivity

1273-481: Is a distinct compound). By 1845 Jamaican-born chemist John Buddle Blyth and German chemist August Wilhelm von Hofmann showed that the same transformation of styrol took place in the absence of oxygen. They called the product "meta styrol"; analysis showed that it was chemically identical to Simon's Styroloxyd. In 1866 Marcellin Berthelot correctly identified the formation of meta styrol/Styroloxyd from styrol as

1340-524: Is a rigid and tough, closed-cell foam with a normal density range of 11 to 32 kg/m . It is usually white and made of pre-expanded polystyrene beads. The manufacturing process for EPS conventionally begins with the creation of small polystyrene beads. Styrene monomers (and potentially other additives) are suspended in water, where they undergo free-radical addition polymerization. The polystyrene beads formed by this mechanism may have an average diameter of around 200 μm. The beads are then permeated with

1407-449: Is a synthetic polymer made from monomers of the aromatic hydrocarbon styrene . Polystyrene can be solid or foamed . General-purpose polystyrene is clear, hard, and brittle. It is an inexpensive resin per unit weight. It is a poor barrier to air and water vapor and has a relatively low melting point. Polystyrene is one of the most widely used plastics , with the scale of its production being several million tonnes per year. Polystyrene

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1474-450: Is about 28–34 kg/m . Extruded polystyrene material is also used in crafts and model building, in particular architectural models. Because of the extrusion manufacturing process, XPS does not require facers to maintain its thermal or physical property performance. Thus, it makes a more uniform substitute for corrugated cardboard . Thermal conductivity varies between 0.029 and 0.039 W/(m·K) depending on bearing strength/density and

1541-437: Is commonly injection molded , vacuum formed , or extruded, while expanded polystyrene is either extruded or molded in a special process. Polystyrene copolymers are also produced; these contain one or more other monomers in addition to styrene. In recent years the expanded polystyrene composites with cellulose and starch have also been produced. Polystyrene is used in some polymer-bonded explosives (PBX). Polystyrene (PS)

1608-489: Is exploited for extrusion (as in Styrofoam ) and also for molding and vacuum forming , since it can be cast into molds with fine detail. The temperatures behavior can be controlled by photocrosslinking. Under ASTM standards, polystyrene is regarded as not biodegradable . It is accumulating as a form of litter in the outside environment , particularly along shores and waterways, especially in its foam form, and in

1675-468: Is generally considered to be non-biodegradable. However, certain organisms are able to degrade it, albeit very slowly. In 2015, researchers discovered that mealworms , the larvae form of the darkling beetle Tenebrio molitor , could digest and subsist healthily on a diet of EPS. About 100 mealworms could consume between 34 and 39 milligrams of this white foam in a day. The droppings of mealworm were found to be safe for use as soil for crops. In 2016, it

1742-410: Is initiated with free radicals . Ziegler–Natta polymerization can produce an ordered syndiotactic polystyrene with the phenyl groups positioned on alternating sides of the hydrocarbon backbone. This form is highly crystalline with a T m (melting point) of 270 °C (518 °F). Syndiotactic polystyrene resin is currently produced under the trade name XAREC by Idemitsu corporation, who use

1809-560: Is measured according to EN 12667. Typical values range from 0.032 to 0.038 W/(m⋅K) depending on the density of the EPS board. The value of 0.038 W/(m⋅K) was obtained at 15 kg/m while the value of 0.032 W/(m⋅K) was obtained at 40 kg/m according to the datasheet of K-710 from StyroChem Finland. Adding fillers (graphites, aluminum, or carbons) has recently allowed the thermal conductivity of EPS to reach around 0.030–0.034 W/(m⋅K) (as low as 0.029 W/(m⋅K)) and as such has

1876-548: Is naturally transparent , but can be colored with colorants. Uses include protective packaging (such as packing peanuts and optical disc jewel cases ), containers, lids, bottles, trays, tumblers, disposable cutlery , in the making of models, and as an alternative material for phonograph records . As a thermoplastic polymer, polystyrene is in a solid (glassy) state at room temperature but flows if heated above about 100 °C, its glass transition temperature . It becomes rigid again when cooled. This temperature behaviour

1943-412: Is not produced commercially. [REDACTED] The only commercially important form of polystyrene is atactic , in which the phenyl groups are randomly distributed on both sides of the polymer chain. This random positioning prevents the chains from aligning with sufficient regularity to achieve any crystallinity . The plastic has a glass transition temperature T g of ~90 °C. Polymerization

2010-732: Is often done to introduce polar groups. Much of modern biomedical research relies on the use of such products; they, therefore, play a critical role in pharmaceutical research. Thin sheets of polystyrene are used in polystyrene film capacitors as it forms a very stable dielectric , but has largely fallen out of use in favor of polyester . Polystyrene foams are 95–98% air. Polystyrene foams are good thermal insulators and are therefore often used as building insulation materials, such as in insulating concrete forms and structural insulated panel building systems. Grey polystyrene foam, incorporating graphite , has superior insulation properties. Carl Munters and John Gudbrand Tandberg of Sweden received

2077-404: Is that the limiting oxygen index of EPS as measured by ASTM D2863 be greater than 24 volume %. Typical EPS has an oxygen index of around 18 volume %; thus, a flame retardant is added to styrene or polystyrene during the formation of EPS. The boards containing a flame retardant when tested in a tunnel using test method UL 723 or ASTM E84 will have a flame spread index of less than 25 and

AN/APQ-7 - Misplaced Pages Continue

2144-723: Is used for producing disposable plastic cutlery and dinnerware , CD "jewel" cases , smoke detector housings, license plate frames, plastic model assembly kits, and many other objects where a rigid, economical plastic is desired. Production methods include thermoforming ( vacuum forming ) and injection molding . Polystyrene Petri dishes and other laboratory containers such as test tubes and microplates play an important role in biomedical research and science. For these uses, articles are almost always made by injection molding, and often sterilized post-molding, either by irradiation or by treatment with ethylene oxide . Post-mold surface modification, usually with oxygen -rich plasmas ,

2211-643: The Eighth Air Force in Europe, but arrived too late for action. Instead, the sets were directed to the new B-29 for use against Japan. Only one unit, the 315th Bombardment Wing of the XXI Bomber Command was fully equipped with Eagle, flying for one month before the war ended. When Nosmo was fitted to the Eagle, the entire assembly became known as the AN/APQ-7A. These had just arrived when

2278-401: The sooty flame. The process of depolymerizing polystyrene into its monomer , styrene , is called pyrolysis . This involves using high heat and pressure to break down the chemical bonds between each styrene compound. Pyrolysis usually goes up to 430 °C. The high energy cost of doing this has made commercial recycling of polystyrene back into styrene monomer difficult. Polystyrene

2345-428: The tacticity , which affects various physical properties of the material. In polystyrene, tacticity describes the extent to which the phenyl group is uniformly aligned (arranged at one side) in the polymer chain. Tacticity has a strong effect on the properties of the plastic. Standard polystyrene is atactic. The diastereomer where all of the phenyl groups are on the same side is called isotactic polystyrene, which

2412-732: The APA-46 and 47 "Nosmo" synchronized a Norden bombsight with the APQ-7, and the entire assembly became known as the APQ-7A. The war ended shortly after this system was introduced, and Eagle saw little real world use. Post-war efforts focused on the K-system , as Eagle's unique antenna design made it difficult to use with higher speed jet powered bombers. Late in 1940, as part of the Tizard Mission , Taffy Bowen had introduced US scientists to

2479-585: The British work on microwave radar using the cavity magnetron . After returning to the UK, Bowen's earlier observation about differences in ground returns noticed in early experiments led Philip Dee to develop a prototype ground mapping system in March 1941, a development that would evolve into the H2S radar . The US was kept apprised of this research. While discussing it in the fall of 1941, Bowen and Alvarez entered

2546-857: The North Pacific Area and the South Pacific Area, were commanded by Fleet Admiral Chester W. Nimitz , Commander-in-Chief Pacific Ocean Areas. The South West Pacific Area (SWPA) was commanded by General of the Army Douglas MacArthur , Supreme Allied Commander South West Pacific Area. During 1945, the United States added the United States Strategic Air Forces in the Pacific , commanded by General Carl A. Spaatz . Because of

2613-602: The Pacific Ocean. Polystyrene was discovered in 1839 by Eduard Simon , an apothecary from Berlin. From storax , the resin of the Oriental sweetgum tree Liquidambar orientalis , he distilled an oily substance, that he named styrol, now called styrene . Several days later, Simon found that it had thickened into a jelly, now known to have been a polymer , that he dubbed styrol oxide ("Styroloxyd") because he presumed that it had resulted from oxidation ( styrene oxide

2680-508: The antenna on a stabilizing platform. Alvarez drew up several concepts for electronic systems to correct for any movement of the aircraft during the scanning. The Rad Lab team initially referred to the concept as the EHIB, short for "Every House in Berlin", which they expected to be able to see. At Lee DuBridge 's insistence, in early 1942 it was renamed "Eagle". By January 1942, a team working on

2747-402: The antenna problem had developed an initial concept consisting of a long rectangular waveguide with small slots cut into the front side. The concept was an early example of what is today referred to as a slot antenna . Radio signals escaping through a slot would interfere with the signal from other slots, strongly suppressing the signal in certain directions while adding up in others. The result

AN/APQ-7 - Misplaced Pages Continue

2814-425: The approach. The proposed set-up would include two displays, a wide angle view used for navigation, and another highly magnified view for precision bombing. By the late summer of 1943 it was clear the UBS was too great a challenge and could delay the entire program. At a 22 October meeting the decision was made to use a simplified bomb aiming system for the immediate future, with a radar operator calling information to

2881-416: The average value is ~0.035 W/(m·K). Water vapor diffusion resistance (μ) of XPS is around 80–250. Commonly extruded polystyrene foam materials include: Although it is a closed-cell foam, both expanded and extruded polystyrene are not entirely waterproof or vapor proof. In expanded polystyrene there are interstitial gaps between the expanded closed-cell pellets that form an open network of channels between

2948-452: The bombardier, who would use a simple mechanical calculator to time the drop. It was clear this was unsatisfactory, but with no other option available in the short term, an order for 40 preproduction Eagle Mark I systems was placed for delivery in August 1944. Many new problems appeared as each part was prepared for production, and by 1 May 1944 Western Electric was satisfied that the design

3015-694: The bonded pellets, and this network of gaps can become filled with liquid water. If the water freezes into ice, it expands and can cause polystyrene pellets to break off from the foam. Extruded polystyrene is also permeable by water molecules and can not be considered a vapor barrier. Water-logging commonly occurs over a long period in polystyrene foams that are constantly exposed to high humidity or are continuously immersed in water, such as in hot tub covers, in floating docks, as supplemental flotation under boat seats, and for below-grade exterior building insulation constantly exposed to groundwater. Typically an exterior vapor barrier such as impermeable plastic sheeting or

3082-997: The complementary roles of the United States Army and the United States Navy in conducting war, the Pacific Theater had no single Allied or U.S. commander (comparable to General of the Army Dwight D. Eisenhower in the European Theater of Operations ). No actual command existed; rather, the Asiatic-Pacific Theater was divided into SWPA, POA, and other forces and theaters, such as the China Burma India Theater . Polystyrene Polystyrene ( PS ) / ˌ p ɒ l i ˈ s t aɪ r iː n /

3149-407: The direction of E.A. Luebke was set up to develop a working system. The Army Air Force, a proponent of precision bombing but unable to achieve it in combat, placed high hopes on the system's ability to attack pinpoint targets, pressing for its development in spite of other systems like H2X beginning to enter production. The first experimental model, with a 3 foot (0.91 m) antenna, was placed on

3216-430: The gut of superworms that contain encoded enzymes associated with the degradation of polystyrene and the breakdown product styrene. The bacterium Pseudomonas putida is capable of converting styrene oil into the biodegradable plastic PHA . This may someday be of use in the effective disposing of polystyrene foam. It is worthy to note the polystyrene must undergo pyrolysis to turn into styrene oil. Polystyrene

3283-471: The item being protected or as loose-fill "peanuts" cushioning fragile items inside boxes. EPS also has been widely used in automotive and road safety applications such as motorcycle helmets and road barriers on automobile race tracks . A significant portion of all EPS products are manufactured through injection molding. Mold tools tend to be manufactured from steels (which can be hardened and plated), and aluminum alloys. The molds are controlled through

3350-467: The molecules consist of thousands of atoms, the cumulative attractive force between the molecules is large. When heated (or deformed at a rapid rate, due to a combination of viscoelastic and thermal insulation properties), the chains can take on a higher degree of confirmation and slide past each other. This intermolecular weakness (versus the high intramolecular strength due to the hydrocarbon backbone) confers flexibility and elasticity. The ability of

3417-544: The operator to sight through the Norden at four (or five depending on the model) locations during the approach. This was quickly replaced by the APA-47, which updated the Norden continuously. This allowed the bombardier to concentrate on the radar display during the approach, and, if the conditions were favourable, move to the Norden at the last minute to achieve higher accuracy. Sets were rushed to B-24 and B-17 units for use with

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3484-434: The polymerization, the carbon-carbon π bond of the vinyl group is broken and a new carbon-carbon σ bond is formed, attaching to the carbon of another styrene monomer to the chain. Since only one kind of monomer is used in its preparation, it is a homopolymer. The newly formed σ bond is stronger than the π bond that was broken, thus it is difficult to depolymerize polystyrene. About a few thousand monomers typically comprise

3551-676: The raw material for molding parts or extruding sheets. BASF and Stastny applied for a patent that was issued in 1949. The molding process was demonstrated at the Kunststoff Messe 1952 in Düsseldorf. Products were named Styropor. The crystal structure of isotactic polystyrene was reported by Giulio Natta . In 1954, the Koppers Company in Pittsburgh , Pennsylvania, developed expanded polystyrene (EPS) foam under

3618-423: The rights to Munters's method and began producing a lightweight, water-resistant, and buoyant material that seemed perfectly suited for building docks and watercraft and for insulating homes, offices, and chicken sheds." In 1944, Styrofoam was patented. Before 1949, chemical engineer Fritz Stastny (1908–1985) developed pre-expanded PS beads by incorporating aliphatic hydrocarbons, such as pentane. These beads are

3685-476: The roof of the Radiation Lab . Although crude, it demonstrated that the basic idea was sound. A 6 foot (1.8 m) version followed late in 1942, and then an 8 foot (2.4 m) one with 108 dipoles in early 1943. It was pointed out that the dihedral and sweepback of most aircraft would make installation of an in-wing scanner difficult, and aeroelastic loads during flight, especially "flapping", would be

3752-461: The same size antenna, which helped reduce the side lobes. All of these slotted designs proved to have poor gain . While working on another project, a microwave-frequency early warning radar , in May 1942 Alvarez conceived using individual dipole antennas instead of slots as the radiating elements. By connecting them to the feed with alternating polarity (180 degrees out of phase), they could be placed side-by-side, instead of being 1 ⁄ 2 of

3819-453: The side lobes. One notable success was made in April 1942, with a new design with a polystyrene dielectric material partially filling the leading edge of the waveguide. The presence of the dielectric slowed the passage of the signal, effectively compressing it, so that the distance between the slots could be reduced and the antenna as a whole was smaller. This allowed there to be more slots in

3886-420: The signal back into a 2D display. The antenna for such a system would have to be large only in the horizontal direction, and could be very thin vertically. This had advantages for installation on aircraft, but it would be even more practical if the beam could be steered electronically, as opposed to mechanically. By delaying the signal slightly as it travelled down the long antenna, which could be arranged through

3953-458: The system to be readily deformed above its glass transition temperature allows polystyrene (and thermoplastic polymers in general) to be readily softened and molded upon heating. Extruded polystyrene is about as strong as an unalloyed aluminium but much more flexible and much less dense (1.05 g/cm for polystyrene vs. 2.70 g/cm for aluminium). Polystyrene is an addition polymer that results when styrene monomers polymerize (interconnect). In

4020-402: The team finally settled on a waveguide consisting of two parallel plates with overlapping barriers on the vertical sides (the front and back of the wave-guide). By mechanically varying the spacing between the two plates, the speed of propagation along the waveguide changed, and steering was achieved. By the summer of 1942 it appeared most of the major problems had been solved, and a new lab under

4087-523: The trade name Dylite. In 1960, Dart Container , the largest manufacturer of foam cups, shipped their first order. In chemical terms, polystyrene is a long chain hydrocarbon wherein alternating carbon centers are attached to phenyl groups (a derivative of benzene ). Polystyrene's chemical formula is (C 8 H 8 ) n ; it contains the chemical elements carbon and hydrogen . The material's properties are determined by short-range van der Waals attractions between polymer chains. Since

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4154-550: The war ended, and did not see combat use. Asiatic-Pacific Theater Second Sino-Japanese War The Asiatic-Pacific Theater was the theater of operations of U.S. forces during World War II in the Pacific War during 1941–1945. From mid-1942 until the end of the war in 1945, two U.S. operational commands were in the Pacific. The Pacific Ocean Areas (POA), divided into the Central Pacific Area,

4221-422: Was a tightly focused beam. However, given the frequencies available, in the X band , any antenna wide enough to produce useful resolution proved to also be wide enough to generate very strong side lobes . These ruined the display, not only leaking away signal uselessly, but also causing returns from the sides of the antenna that could not be distinguished from ones in front of it. Many attempts were made to reduce

4288-478: Was also reported that superworms ( Zophobas morio ) may eat expanded polystyrene (EPS). A group of high school students in Ateneo de Manila University found that compared to Tenebrio molitor larvae, Zophobas morio larvae may consume greater amounts of EPS over longer periods of time. In 2022 scientists identified several bacterial genera, including Pseudomonas , Rhodococcus and Corynebacterium , in

4355-442: Was not convinced of one part of the argument – the need for the system to be accurate in elevation. He considered it to be an advantage if the system scanned a wide angle vertically, receiving a signal from a long "strip" of the ground all at once. Since the radar returns from ground closer to the aircraft would be received first, a display being drawn outward from the center, the classic Plan Position Indicator , would naturally decode

4422-778: Was ready for manufacture. The company used a dilapidated building on 42nd Street in New York City as the assembly site, and began ordering the 1813 separate parts from manufacturers nationwide. The first five sets were assembled at Bell Labs in July 1944, and another 33 were completed by August and the last of the 50 preproduction sets in September. The first production sets from the new plant arrived on 28 September, with 40 more in October, and another 142 in November. While production

4489-484: Was starting, the problem of bombing with two crew members was proving even worse than initially thought. Meanwhile, other radar systems, like H2X , were demonstrating the problem of trying to calculate the bomb trajectory while operating the radar. The solution was to build a system that linked the radar's output to the Norden's input. The first such device, the AN/APA-46 Adapter Assembly, allowed

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