omniomni/omni-engineering huggingface dataset:
Type Two 63 ft HSL. The Type Two HSL was a 63 ft high-speed launch craft made by British Power Boat Company (BPBC). The craft were used during the Second World War for air-sea rescue operations to save Allied aircrew from the sea. The Type Two superseded the 64 ft HSL, and was itself replaced by the Type Three 68 ft "Hants and Dorset" also built by the BPBC. The Type Two (aka Type 2) was nicknamed the "Whaleback" due to the distinctive curve to its deck and humped cabin.

History

The Type Two was designed in 1937 by George Selman, Chief Designer and Naval Architect of the British Power Boat Company, which was founded by Hubert Scott-Paine at Hythe. Scott-Paine had previously owned the Supermarine Aviation Company, later builders of the Supermarine Spitfire and several flying boat types.

A low-set cabin contained the wheel-house, chart room and a sickbay. For defence against enemy aircraft, on top of the cabin were two aircraft-style turrets made by Armstrong-Whitworth initially with a single .303 in Vickers K gun or Lewis gun (later improved to paired guns of the same calibre). The mahogany hull was of the hard chine, planing type.

Usage
During the Second World War, the retrieval of pilots and aircrew who had been shot down over, or who had had to ditch in, the sea around the British Isles was the responsibility of the Royal Air Force Marine Branch, (motto: "The sea shall not have them"). Rescue of downed aircrew was coordinated using RAF aircraft, aircraft operated by Coastal Command and the Royal Navy and rescue launches operated by the RAF Marine Branch and the Royal Navy.

The Type Two was supplied to RAF marine craft units from the middle of 1940. In total, 69 craft were manufactured between 1940 and 1942.

After World War II, a number of the Type Two craft were transferred to the Royal Navy and a small number were given to the Italian Air Force. The vast majority of the Type Two craft belonging to the Admiralty were subsequently stored and later sold off as houseboats. None are currently owned by any museum or trusts.

Variants
Following their performance during the  Dieppe raid in August 1942, the Type Two was modified. Extra armament was fitted – paired .303 in machine guns mounted either side of the wheel-house and a single 20 mm Oerlikon on the (strengthened) rear deck. Protection was improved by adding anti-shrapnel padding around the forward cabin area.

See also
 Crash boats of World War 2
 Crash rescue boat
 For Those in Peril – 1944 British propaganda film that is based on the RAF air-sea rescue service featuring Type Two craft.
 Motor launch
 The Sea Shall Not Have Them
 Wooden boats of World War 2

References

External links

 Comprehensive list of RAF boats
 A photograph of high-speed launch HSL 164 at speed

Royal Air Force Marine Branch
Boat types
High-speed craft
World War II military equipment of the United Kingdom
Military boats
EMD MP15T. The EMD MP15T is a model of diesel-electric switcher locomotives built by General Motors Electro-Motive Division between October 1984 and November 1987. Instead of a non-turbocharged 12-cylinder EMD 645 engine it uses a turbocharged 8-cylinder engine. The external appearance of the engine remains similar to other MP15 models.

42 of these locomotives were built for the Seaboard System Railroad, 1200–1241 (later merged into CSX Transportation where they kept their numbers) and one unit for Dow Chemical Company, number 957.

In 2010 Progress Rail, a fully owned subsidiary of Caterpillar, purchased MP15T 1220 from CSX making CSX's total count 40.

See also
 List of GM-EMD locomotives

References

External links
 
 Sarberenyi, Robert. EMD MP15DC, MP15AC, and MP15T Original Owners

MP15T
Seaboard System Railroad
B-B locomotives
Diesel–electric locomotives of the United States
Railway locomotives introduced in 1984
Standard gauge locomotives of the United States
Shunting locomotives
BAE Systems Avionics. BAE Systems Avionics was the avionics unit of BAE Systems until 2005, at which time it was transferred to SELEX Sensors and Airborne Systems S.p.A. (initially 75% Finmeccanica and 25% BAE Systems, but since March 2007 fully owned by Finmeccanica). Selex S&AS became SELEX Galileo in 2008 and from January 2013 (following a merger with other Finmeccanica companies SELEX Sistemi Integrati and Selex Elsag) traded as Selex ES. It then merged into Leonardo S.p.A.'s land and naval defence electronics division on 1 January 2016.

The business had its UK headquarters in Basildon, Essex, England.

History
BAE Systems Avionics has a rich heritage which dates back to 1909 when the Elliott and Marconi companies began to fit aircraft with systems (beginning with embryonic air to ground communications). By 1913 Elliot's avionics product lines advanced to gyroscopes, weapon sights and altimeters.

Timeline
1804 - William Elliott establishes a company manufacturing scientific and surveying instruments.
1853 - Company renamed Elliott Brothers.
1897 - Guglielmo Marconi founds his company.
1909 - Elliott Brothers and Marconi companies both begin to fit avionics to early aircraft.
1946 - Marconi is acquired by English Electric.
1967 - English Electric and Elliott Automation merge.
1968 - The new English Electric group is acquired by GEC.
1969 - GEC renames avionics business Marconi-Elliott Avionics Systems Limited, part of the company's defence arm, GEC-Marconi.
1978 - Renamed Marconi Avionics Limited.
1984 - Renamed GEC Avionics Limited.
1990 - Take-over of Ferranti creating GEC Ferranti
1998 - Renamed Marconi Avionics, part of the renamed defence arm, Marconi Electronic Systems (MES).
1999 - MES merged with British Aerospace to form BAE Systems. Avionics business becomes BAE Systems Avionics.
2005 - Parts of BAE Systems Avionics merged with Galileo Avionica to form SELEX Sensors and Airborne Systems.
2008 - SELEX Sensors and Airborne Systems is re-branded SELEX Galileo.
2013 - SELEX Galileo merged with SELEX Sistemi Integrati and Selex Elsag to form Selex ES.
2016 - Selex ES activities became part of Leonardo’s land and naval defence electronics division

References

Sources
The Changing World of Avionics, G.M. Barling. GEC Review, Vol. 6 1990
Elliott early history

Aircraft component manufacturers of the United Kingdom
British companies established in 1969
Avionics companies
BAE Systems subsidiaries and divisions
Borough of Basildon
Companies based in Essex
Defence companies of the United Kingdom
Defunct companies of the United Kingdom
Electronics companies of the United Kingdom
Manufacturing companies established in 1969
Science and technology in Essex
2005 mergers and acquisitions
Bismuthide. The bismuthide ion is  but the term is often used to describe less reduced forms of bismuth.

Bismuthides are compounds of bismuth with more electropositive elements. A wide variety are known.  

The stoichiometry of bismuthides ranges from lithium bismuthide (Li3Bi), which can be viewed as the Li+ salt of Bi3-.  The corresponding sodium and potassium derivatives are also known.  They all prepared by heating the elements.

In terms of Bi-rich phases, examples are LiBi, KBi2, CaBi3, which exhibit strong Bi-Bi bonding. Some are intermetallic compounds, containing partially metallic and partially ionic bonds.  The majority of bismuthides adopt efficient packing arrangements and become densely packed structures, which is a characteristic of intermetallic compounds.

See also
 Bismanol, a magnetic alloy of bismuth and manganese
 Zintl phase

References

Anions
Bismuth
Bismuthides
Krennerite. Krennerite is an orthorhombic gold telluride mineral which can contain variable amounts of  silver in the structure. The formula is AuTe2, but specimen with gold substituted by up to 24% with silver have been found ([Au0.77Ag0.24]Te2). Both of the chemically similar gold-silver tellurides, calaverite and sylvanite, are in the monoclinic crystal system, whereas krennerite is orthorhombic.

The color varies from silver-white to brass-yellow. It has a specific gravity of 8.62 and a hardness of 2.5. It occurs in high temperature, hydrothermal environments. 

Krennerite was discovered in 1878 near the village of Săcărâmb, Romania, and first described by the Hungarian mineralogist Joseph Krenner (1839–1920).

See also
List of minerals
List of minerals named after people

References

G. Tunnell and K. J. Murata, American Mineralogist 35, 359–384 (1950).
Structure of Krennerite retrieved 6-26-05
Euromineral retrieved 6-26-05

Silver minerals
Gold minerals
Telluride minerals
Orthorhombic minerals
Minerals in space group 28
Minerals described in 1878
DYSEAC. DYSEAC was the second Standards Electronic Automatic Computer. (See SEAC.)

DYSEAC was a first-generation computer built by the National Bureau of Standards for the U.S. Army Signal Corps. It was housed in a truck, making it one of the first movable computers (perhaps the first). It went into operation in April 1954.

DYSEAC used 900 vacuum tubes and 24,500 crystal diodes. It had a memory of 512 words of 45 bits each (plus one parity bit), using mercury delay-line memory. Memory access time was 48–384 microseconds. The addition time was 48 microseconds, and the multiplication/division time was 2112 microseconds. These times are excluding the memory-access time, which added up to approximately 1500 microseconds to those times.

DYSEAC may have been the first computer to implement interrupts for I/O.

DYSEAC weighed about .

See also
 SEAC
 List of vacuum-tube computers

References

External links
 BRL report on computers, inc. DYSEAC
 Astin, A. V. (1955), Computer Development (SEAC and DYSEAC) at the National Bureau of Standards, Washington D.C., National Bureau of Standards Circular 551, Issued January 25, 1955, U.S. Government Printing Office. Fully viewable online. Includes several papers describing the technical details and operation of both DYSEAC and its predecessor SEAC, from which DYSEAC was derived. In particular, see "DYSEAC", by A. L. Leiner, S. N. Alexander, and R. P. Witt, on pp. 39–71, for an overview of DYSEAC and its differences from SEAC.
 

One-of-a-kind computers
Vacuum tube computers
Portable computers
Serial computers
FR-2. FR-2 (Flame Resistant 2) is a NEMA designation for synthetic resin bonded paper, a composite material made of paper impregnated with a plasticized phenol formaldehyde resin, used in the manufacture of printed circuit boards. Its main properties are similar to NEMA grade XXXP (MIL-P-3115) material, and can be substituted for the latter in many applications.

Applications 
FR-2 sheet with copper foil lamination on one or both sides is widely used to build low-end consumer electronics equipment. While its electrical and mechanical properties are inferior to those of epoxy-bonded fiberglass, FR-4, it is significantly cheaper. It is not suitable for devices installed in vehicles, as continuous vibration can make cracks propagate, causing hairline fractures in copper circuit traces. Without copper foil lamination, FR-2 is sometimes used for simple structural shapes and electrical insulation.

Properties

Fabrication 
FR-2 can be machined by drilling, sawing, milling and hot punching. Cold punching and shearing are not recommended, as they leave a ragged edge and tend to cause cracking. Tools made of high-speed steel can be used, although tungsten carbide tooling is preferred for high volume production.

Adequate ventilation or respiration protection are mandatory during high-speed machining, as it gives off toxic vapors.

Trade names and synonyms 
 Carta
 Haefelyt
 Lamitex
 Paxolin, Paxoline
 Pertinax, taken over by Lamitec and Dr. Dietrich Müller GmbH in 2014
 Getinax (in the Ex-USSR)
 Phenolic paper
 Preßzell
 Repelit
 Synthetic resin bonded paper (SRBP)
 Turbonit
 Veroboard
 Wahnerit

See also 
 Formica (plastic)
 Micarta

References

Further reading
 

Composite materials
Printed circuit board manufacturing
Synthetic paper
MANIAC II. The MANIAC II (Mathematical Analyzer Numerical Integrator and Automatic Computer Model II) was a first-generation electronic computer, built in 1957 for use at Los Alamos Scientific Laboratory.

MANIAC II was built by the University of California and the Los Alamos Scientific Laboratory, completed in 1957 as a successor to MANIAC I.  It used 2,850 vacuum tubes and 1,040 semiconductor diodes in the arithmetic unit. Overall it used 5,190 vacuum tubes, 3,050 semiconductor diodes, and 1,160 transistors.

It had 4,096 words of memory in Magnetic-core memory (with 2.4 microsecond access time), supplemented by 12,288 words of memory using Williams tubes (with 15 microsecond access time). The word size was 48 bits.  Its average multiplication time was 180 microseconds and the average division time was 300 microseconds.

By the time of its decommissioning, the computer was all solid-state, using a combination of
RTL, DTL and TTL. It had an array multiplier, 15 index registers, 16K of 6-microsecond cycle time core memory, and 64K of 2-microsecond cycle time core memory. A NOP instruction took about 2.5 microseconds. A multiplication took 8 microseconds and a division 25 microseconds. It had a paging unit using 1K word pages with an associative 16-deep lookup memory. A 1-megaword CDC drum was hooked up as a paging device. It also had several ADDS Special-Order Direct-View Storage-Tube terminals. These terminals used an extended character set which covered about all the mathematical symbols, and allowed for half-line spacing for math formulas. 
For I/O, it had two IBM 360 series nine-track and two seven-track 1/2" tape drives. It had an eight-bit paper-tape reader and punch, and a 500 line-per-minute printer (1500 line-per-minute using the hexadecimal character set). Storage was three IBM 7000 series 1301 disk drives, each having two modules of 21.6 million characters apiece.

One of the data products of MANIAC II was the table of numbers appearing in the book The 3-j and 6-j Symbols by Manuel Rotenberg, et al., published in 1959.  Page 37 of that book contains a brief description of the implementation of the program on the computer, and the I/O devices used in the production of the book.

See also
List of vacuum-tube computers
MANIAC I
MANIAC III

Further reading

External links
 BRL report on MANIAC II

One-of-a-kind computers
Vacuum tube computers
48-bit computers
SMIL (computer). SMIL (, "The Number Machine in Lund") was a first-generation computer built at Lund University in Lund, Sweden. SMIL was based on the IAS architecture developed by John von Neumann.

Carl-Erik Fröberg belonged to the group of five young Swedish scientists 1947–48 that IVA sent to the U.S. to gather information about the early computer development, and then came to strongly influence the development in Sweden. Fröberg visited with Erik Stemme the Institute for Advanced Study, and John von Neumann's research group. Back in Lund, he played a leading role in the creation of SMIL, which was the first computer developed in Lund and among the first in Sweden. SMIL was introduced in 1956 and then was in operation until 1970.

In February 1962 SMIL was fitted with a compiler for ALGOL 60. The compiler was constructed by Torgil Ekman and Leif Robertson.

Carl-Erik Fröberg was also behind the early emergence of numerical analysis as a separate university subject. In this context, he wrote himself and collaborated with others on several textbooks in computer education, for example, Textbook on Numerical Analysis (1962) and Textbook of Algol (1964). These books were widely distributed and translated into several languages.

Parts of SMIL are exhibited at Malmö Technical Museum.

On January 4, 2006, an emulator of SMIL named SMILemu was released with a Java and  version.

See also 
 BARK - Binär Aritmetisk Relä-Kalkylator - Sweden's first computer
 BESK - Binär Elektronisk Sekvens-Kalkylator - Sweden's second computer
 Torsten Hägerstrand – a Swedish geographer (and friend of Fröberg) who used SMIL

References

IAS architecture computers
Lund University
Sulfide stress cracking. Sulfide stress cracking (SSC) is a form of hydrogen embrittlement which is a cathodic cracking mechanism. It should not be confused with the term stress corrosion cracking which is an anodic cracking mechanism. Susceptible alloys, especially steels, react with hydrogen sulfide (), forming metal sulfides (MeS) and atomic hydrogen (H•) as corrosion byproducts. Atomic hydrogen either combines to form H2 at the metal surface or diffuses into the metal matrix. Since sulfur is a hydrogen recombination poison, the amount of atomic hydrogen which recombines to form H2 on the surface is greatly reduced, thereby increasing the amount of diffusion of atomic hydrogen into the metal matrix. This aspect is what makes wet H2S environments so severe.

Since SSC is a form of hydrogen embrittlement, it is most susceptibile to cracking at or slightly below ambient temperature.

Sulfide stress cracking has special importance in the gas and oil industry, as the materials being processed there (natural gas and crude oil) often contain considerable amounts of hydrogen sulfide. Equipment that comes in contact with H2S environments can be rated for sour service with adherence to NACE MR0175/ISO 15156 for oil and gas production environments or NACE MR0103/ISO17945 for oil and gas refining environments.

"High Temperature Hydrogen Attack" (HTHA) does not rely on atomic hydrogen.  At high temperature and high hydrogen partial pressure, hydrogen can diffuse into carbon steel alloys.  In susceptible alloys, hydrogen combines with carbon within the alloy and forms methane.  The methane molecules create a pressure buildup in the metal lattice voids, which leads to embrittlement and even cracking of the metal.

See also
 Corrosion engineering
 Crevice corrosion
 Pitting corrosion
 Sulfidation

References

Corrosion
Materials degradation
Staballoy. Staballoy is the name of two different classes of metal alloys, one class typically used for munitions and a different class developed for drilling rods.

Kinetic penetrators
In a military context, staballoys are metal alloys of a high proportion of depleted uranium with other metals, usually titanium or molybdenum, designed for use in kinetic energy penetrator armor-piercing munitions. One formulation has a composition of 99.25% of depleted uranium and 0.75% of titanium. Other variants can have 3.5% of titanium. They are about 65% more dense than lead.

An alternative to staballoys in kinetic penetrator munition is tungsten, but it is more expensive, more difficult to machine and is not pyrophoric, so the munition lacks the incendiary effect enhancing its impact. Tungsten penetrators also tend to form a mushroom shaped tip during armor penetration, while uranium ones tend to be self-sharpening.

An emerging alternative alloy of depleted uranium is stakalloy, formed of niobium (0.01-0.95 wt.%), vanadium (1-4.5 wt.%, between gamma-eutectoid and eutectic) and uranium (balance). It has improved machinability. It can be used in structural applications too.

Drilling rods
Staballoy is also a name for a class of commercially used stainless steels used for drilling rods for drilling rigs. An example is Staballoy AG17 which is a different material from military staballoy, and contains 20.00% manganese, 17.00% chromium, 0.30% silicon, 0.03% carbon, 0.50% nitrogen, and 0.05% molybdenum, alloyed with iron. It is nonmagnetic.

References

Alloys
Ammunition
Uranium compounds
Tungsten alloys
Sunstone. Sunstone is a microcline or oligoclase feldspar, which when viewed from certain directions  exhibits a spangled appearance. It has been found in Southern Norway, Sweden, various United States localities and on some beaches along the midcoast of South Australia.

Properties

Physical properties 

The optical effect is due to reflections from inclusions of red copper, hematite, or goethite, in the form of minute scales, which are hexagonal, rhombic, or irregular in shape, and are disposed parallel to the principal cleavage-plane. These inclusions give the stone an appearance something like that of aventurine, hence sunstone is known also as "aventurine-feldspar". The optical effect is called schiller and the color of Oregon Sunstone is due to copper. The middle part of this crystal sparkles, and usually the color is darkest in the middle and becomes lighter toward the outer edges.

The feldspar which usually displays the aventurine appearance is oligoclase, though the effect is sometimes seen in orthoclase: hence two kinds of sunstone are distinguished as "oligoclase sunstone" and "orthoclase sunstone".

Distribution
Sunstone was not popular until recently. Previously the best-known locality being Tvedestrand, near Arendal, in south Norway, where masses of the sunstone occur embedded in a vein of quartz running through gneiss.

Other locations include near Lake Baikal in Siberia, and several United States localities—notably at Middletown Township, Delaware County, Pennsylvania; Plush, Oregon; and Statesville, North Carolina.

The "orthoclase sunstone" variant has been found near Crown Point and at several other localities in New York, as also at Glen Riddle in Delaware County, Pennsylvania, and at Amelia Courthouse, Amelia County, Virginia.

Sunstone is also found in Pleistocene basalt flows at Sunstone Knoll in Millard County, Utah.

Andesine controversy

In the early 2000s, a new variety of red or green gemstone resembling sunstone and known as "Andesine" appeared in the gem market.  After much controversy and debate, most of these gemstones, allegedly sourced from China, were subsequently discovered to have been artificially colored by a copper diffusion process. A Tibetan source of bona fide (untreated) red andesine, however, was eventually verified by a number of independent groups of well-respected gemologists.

Oregon sunstone
A variety known as "Oregon sunstone" is found in Harney County, Oregon and in eastern Lake County north of Plush. Oregon Sunstone contains elemental copper. Oregon Sunstone is unique in that crystals can be quite large. The copper leads to variant color within some stones, where turning one stone will result in manifold hues: the more copper within the stone, the darker the complexion.

On August 4, 1987, the Oregon State Legislature designated Oregon Sunstone as its state gemstone by joint resolution.

See also
Rainbow lattice sunstone

References

External links

Mineralogy Database

Feldspar
Symbols of Oregon
Gemstones