omniomni/omni-engineering huggingface dataset:
Refractometry. Refractometry is the analytical method of measuring substances' refractive index (one of their fundamental physical properties) in order to, for instance, assess their composition or purity. A refractometer is the instrument used to measure refractive index ("RI"). Although refractometers are best known for measuring liquids, they are also used to measure gases and solids, such as glass and gemstones.

The RI of a substance is strongly influenced by temperature and the wavelength of light used to measure it; therefore, care must be taken to control or compensate for temperature differences and wavelength. RI measurements are usually reported at a reference temperature of 20 degrees Celsius, which is equal to 68 degrees Fahrenheit and is considered to be room temperature.  A reference wavelength of 589.3 nm (the sodium D line) is most often used. Though RI is a dimensionless quantity, it is typically reported as nD20 (or n), where the "n" represents refractive index, the "D" denotes the wavelength, and the 20 denotes the reference temperature. Therefore, the refractive index of water at 20 degrees Celsius, taken at the Sodium D Line, would be reported as 1.3330 nD20.

Refractometers are frequently used by grape growers and kiwifruit growers for Brix testing of sucrose levels in their fruit. Refractometry is also used in the gelatin industry.  To convert the RI of a gelatin sol (reported in Brix) to a gelatin concentration, one need only multiply by eight-tenths (0.8).  A sol with a 10.0 RI would therefore be 8% gelatin by weight.  This is known to be a reliable conversion for gelatin sols as low as 1% up to over 50%.

Types of refractometers

There are four main types of fluid refractometers: traditional handheld refractometers, digital handheld refractometers, Abbe refractometers, and inline process refractometers.

Further reading

External links
Refractometry - Gemstone Buzz methods for measuring refractive index.

Measurement
Protei-5 Russian diver propulsion vehicle. The Protei-5 (Протей-5) is a small Russian one-man diver propulsion vehicle often used by Russian commando frogmen. It is battery electric powered, using six non-sealed lead–acid batteries. It clips on under the diver with a clip over each shoulder and one up between his legs. Its casing is aluminium. It was intended to be clipped onto the outside of a submarine; near the operation site the frogmen would airlock out underwater and unhitch their Protei 5's and ride them to the operation site. It seems to have been intended to be ridden fast and far rather than for complicated maneuvering.

The Russian for this sort of "diver-carrying vehicle" is буксировщик buksirovshchik = "tugger".

The rod sticking out of the front end was meant to carry a lamp.
The lever on the left bow is the motor's on/off switch. There is no speed control.
The frogman steers with the diving fins on his feet.
Overall size: 66 centimetres (2 feet 2 inches) wide, 69 centimetres (2 feet 3 inches) high, 1.75  (5 feet 9 inches) long.
Size of hull: 66 centimetres (2 feet 2 inches) wide, 38 centimetres (1 feet 3 inches) high, 1.45 m (4 feet 9 inches) long.

A frogman with an IDA71 rebreather riding a Protei-7 could pass through a hole  square.

Only two Protei-5 are known to exist outside of the ex-USSR:
 One is currently in upstate New York, USA.
 One is fully operational in New Jersey, USA; it was made in 1970 and its motor is noisy. This example was imported along with some 150 IDA-59, IDA-64, IDA-71, and AKA-60 rebreathers, all ex-Soviet military combat swimmers' systems.

Similar designs have been made in Russia, including a model called Proton.

The name "Protei" is a Russian version of the classical Latin / Greek mythological name Proteus.

References

External links
article "Riding on Proton" by Afonchenko (in Russian, with 6 images, about diving with a similar craft called a Proton)
Search for Youtube videos about the Protei-5
Some Protei 5's got into American hands and were filmed used by a civilian; to at least one of them a civilian user (who also repainted it) added a long front pair of handlebars, which is not part of them as made in the USSR.

Underwater diver propulsion equipment
Military equipment of the Soviet Union
Soviet inventions
Jakob Amsler-Laffon. Jakob Amsler-Laffon (11 November 1823 – 3 January 1912) was a mathematician, physicist, engineer and the founder of his own factory. Amsler was born on the Stalden near the village of Schinznach in the district of Brugg, canton Aargau, and died in Schaffhausen, Switzerland. His father was Jakob Amsler-Amsler (1779–1869).

On graduating from school in 1843, he went to the University of Jena and then to the University of Königsberg to study theology. At Königsberg he changed courses, deciding to focus on mathematics and physics after meeting the inspiring Franz Neumann. Among Amsler's fellow students at Königsberg were Gustav Robert Kirchhoff and Siegfried Heinrich Aronhold. Amsler gained his doctorate from Königsberg in 1848 and returned to Switzerland in the same year. In 1851 he became a Privatdozent at the University of Zürich and later in that year accepted a position as a mathematics teacher at the Gymnasium in Schaffhausen. In 1854 Amsler married Elise Laffon (1830–1899). The couple had two daughters and three sons. Their oldest son Alfred Amsler (1857–1940) was a mathematician and engineer in his own right and succeeded to his father as the owner and director of the factory. From about 1885 until about 1905, father and son closely cooperated on many projects in their business; many of their ideas, inventions and constructions of the time are difficult to attribute to either one of them.

Jakob Amsler-Laffon invented the polar planimeter in 1854.

Publications 
 Jakob Amsler: Über die mechanische Bestimmung des Flächeninhaltes, der statischen Momente und der Trägheitsmomente ebener Figuren. Schaffhausen, 1856.
 Jakob Amsler: Anwendung des Integrators (Momentenplanimeters) zur Berechnung des Auf- und Abtrages bei Anlage von Eisenbahnen, Strassen und Kanälen. Zürich, 1875.
 Jakob Amsler: Moulinet hydrométrique avec compteur et signal électrique. Schaffhouse, w.o.year.
 J. Amsler-Laffon & Sohn: Catalog der Materialprüfmaschinen. Schaffhausen, 1903.

References 
 
 
 Robert Amsler & Theodor H. Erismann: Jakob-Amsler Laffon 1823–1912 Alfred Amsler 1857–1940 Pioniere der Prüfung und Präzision. Meilen: Verein für wirtschaftshistorische Studien. 1993.

External links 
Author profile in the database zbMATH 

1823 births
1912 deaths
People from Brugg District
19th-century Swiss mathematicians
20th-century Swiss mathematicians
People from Schaffhausen
Single instruction, single data. In computing, single instruction stream, single data stream (SISD) is a computer architecture in which a single uni-core processor executes a single instruction stream, to operate on data stored in a single memory. This corresponds to the von Neumann architecture.

SISD is one of the four main classifications as defined in Flynn's taxonomy. In this system, classifications are based upon the number of concurrent instructions and data streams present in the computer architecture. According to Michael J. Flynn, SISD can have concurrent processing characteristics. Pipelined processors and superscalar processors are common examples found in most modern SISD computers.

Instructions are sent to the control unit from the memory module and are decoded and sent to the processing unit which processes on the data retrieved from memory module and sends back to it.

References

Flynn's taxonomy
SISD
DSV. DSV may refer to:

In sports:
 DSV Leoben, a football team based in Leoben, Austria
 German Swimming Federation (Deutscher Schwimm-Verband)
 German Ski Association (Deutscher Skiverband)

In transportation:
 DSV (company), a Danish transport company
 Dansville Municipal Airport (IATA code) in Dansville, New York
 deep-submergence vehicles, deep-diving self-propelled crewed submarines (in particular in the names of US Navy submersibles)
 diving support vessel, a ship used in commercial diving
 German State Railway Wagon Association (Deutscher Staatsbahnwagenverband)

In computing:

 delimiter-separated values, a way to store two-dimensional arrays of data, in textual form

In culture:
 seaQuest DSV, an American science fiction television series (later renamed seaQuest 2032)

In other uses:
 Deutsche Schule Valparaiso, a German international school in Viña del Mar/Valparaiso, Chile
 Deutsche Schule Valencia, a German international school in Valencia, Spain
 Life Sciences Division (Division des Sciences du Vivant) of the French Alternative Energies and Atomic Energy Commission
 Sovereigntist Right in French Politics
Columnar phase. The columnar phase is a class of mesophases in which molecules assemble into cylindrical structures to act as mesogens. Originally, these kinds of liquid crystals were called discotic liquid crystals or bowlic liquid crystals  because the columnar structures are composed of flat-shaped discotic or bowl-shaped molecules stacked one-dimensionally. Since recent findings provide a number of columnar liquid crystals consisting of non-discoid mesogens, it is more common now to classify this state of matter and compounds with these properties as columnar liquid crystals.

Takuzo Aida and co-workers recently reported cyclic peptides that self-assemble into polar columnar organizations.  These materials can be unidirectionally aligned over large areas by application of an external electric field.

Classes
Columnar liquid crystals are grouped by their structural order and the ways of packing of the columns. Nematic columnar liquid crystals have no long-range order and are less organized than other columnar liquid crystals. Other columnar phases with long-range order are classified by their two-dimensional lattices: hexagonal, tetragonal, rectangular, and oblique phases.

The discotic nematic phase includes nematic liquid crystals composed of flat-shaped discotic molecules without long-range order. In this phase, molecules do not form specific columnar assemblies but only float with their short axes in parallel to the director (a unit vector which defines the liquid-crystalline alignment and order).

Current topics of interest
The first discotic liquid crystal was found in 1977 by the Indian researcher Sivaramakrishna Chandrasekhar. This molecule has one central benzene ring surrounded by six alkyl chains. Since then, a large number of discoid mesogenic compounds have been discovered in which triphenylene, porphyrin, phthalocyanine, coronene, and other aromatic molecules are involved. The typical columnar liquid-crystalline molecules have a pi-electron-rich aromatic core attached by flexible alkyl chains. This structure is attracting particular attention for potential molecular electronics in which aromatic parts transport electrons or holes and alkyl chains act as insulating parts. The advantages of liquid-crystalline conductors are their anisotropy, processibility, and self-healing characteristics for structural defects.

References

 David Dunmur & Tim Sluckin (2011) Soap, Science, and Flat-screen TVs: a history of liquid crystals, pp 258–62, Oxford University Press  .

Liquid crystals
Prime mover. Prime mover may refer to:

Philosophy
Unmoved mover, a concept in Aristotle's writings

Engineering
 Prime mover (engine or motor), a machine that converts various other forms of energy (chemical, electrical, fluid pressure/flow, etc.) into energy of movement
 Prime mover (locomotive), one of the several types of power plants used in locomotives to provide traction power
 Prime mover (tractor unit), a heavy-duty towing engine that provides motive power for hauling a towed or trailered load

Anatomy
 Prime mover, another name for an agonist muscle

Entertainment
 Prime Mover (film), a 2009 Australian romantic crime film
 Prime Mover (comics), a fictional character in the Marvel Universe
 Prime Mover, a video game published by Psygnosis in 1993
 "The Prime Mover", a 1961 episode of The Twilight Zone
 The Prime Movers, a quasi-omniscient race of alien superbeings in the Buck Godot comic series by Phil Foglio

Music
  Prime Mover (album), a 1988 album by the Christian Rock band AD
 The Prime Movers (Michigan band), a 1960s band featuring a pre-Stooges Iggy Pop
 The Prime Movers (Los Angeles band), a predecessor band of Dread Zeppelin
 Prime Movers (Slim Dusty album), a 2016 compilation by Slim Dusty
 "Prime Mover", a 1983 single by Leather Nun 
 "Prime Mover", a 1987 single by Zodiac Mindwarp
 "Prime Mover", a song on Rush's 1987 album Hold Your Fire
 "Prime Mover", a song on Ghost's 2010 album Opus Eponymous
 "Prime Mover", a 2012 album by German trance producer Alex M.O.R.P.H.
 "Prime Movers", a song on Covenant's 2013 album Leaving Babylon
 The Prime Movers, a band of former members of The Prisoners

See also
 First mover (disambiguation)
Metol. Metol (or Elon) is a trade name for the organic compound with the formula [HOC6H4NH2(CH3)]2HSO4. It is the sulfate salt of N-methylaminophenol. This colourless salt is a popular photographic developer used in monochrome photography.

Synthesis and degradation
Several methods exist for the preparation of N-methylaminophenol. It arises by decarboxylation of N-4-hydroxyphenylglycine (Glycin).  It can be obtained by reaction of hydroquinone with methylamine.

Being an electron-rich arene, metol is readily degraded by hydrogen peroxide.

Application
Metol is an excellent developing agent for most continuous tone developer applications, and it has been widely used in published developer formulas as well as commercial products. However, it is difficult to produce highly concentrated developer solutions using Metol, and therefore most Metol developers are supplied in dry chemical mix. A developer containing both Metol and hydroquinone is called an MQ developer. This combination of agents provides greater developer activity since the rate of development by both agents together is greater than the sum of rates of development by each agent used alone (superadditivity). This combination is very versatile; by varying the quantities of Metol, hydroquinone, and restrainer, and adjusting the pH, the entire range of continuous tone developers can be made. Therefore, this form of Metol replaced most other developing agents except for hydroquinone, Phenidone (which is more recent than Metol), and derivatives of Phenidone. Notable formulas include Eastman Kodak D-76 film developer, D-72 print developer, and D-96 motion picture negative developer.

History
Alfred Bogisch, working for a chemical company owned by Julius Hauff, discovered in 1891 that methylated p-aminophenol has more vigorous developing action than p-aminophenol. Hauff introduced this compound as a developing agent. The exact composition of Bogisch and Hauff's early Metol is unknown, but it was most likely methylated at the ortho position of the benzene ring (p-amino-o-methylphenol), rather than at the amino group. Some time later, Metol came to mean the N-methylated variety, and the o-methylated variety fell out of use. Aktien-Gesellschaft für Anilinfabrikation (AGFA) sold this compound under the trade name Metol, which became by far the most common name, followed by Eastman Kodak's trade name Elon.

Because it has been in use for this purpose for over 100 years, and often by amateur photographers, there is a substantial body of evidence regarding the health problems that contact with Metol can cause. These are principally local dermatitis of the hands and forearms. There is also some evidence of sensitization dermatitis.

References

Photographic chemicals
4-Hydroxyphenyl compounds
Digital Angel. Digital Angel Corporation is a developer and publisher of consumer applications and mobile games designed for tablets, smartphones and other mobile devices, as well as a distributor of two-way communications equipment in the U.K.

Products and services 
The company formerly developed Global Positioning System (GPS) and radio-frequency identification (RFID) technology products for consumer, commercial, and government sectors. The company manufactured tracking devices for people, animals, the food supply, government/military arena, and commercial assets. Included in this product line were RFID applications, end-to-end food safety systems, GPS/Satellite communications, and telecommunication, security infrastructure, and the controversial Verichip human implant, a product which has caused concern among advocates of civil liberties.

Applications for this technology include pets, wildlife and livestock identification using implantable RFID microchips, scanners and antennas.

Digital Angel has also researched and developed GPS Search and Rescue Transponders that integrated geosynchronous communications for use by the military and the private sector to track aircraft, ships, and other high-value assets.

History
Digital Angel formerly owned a minority position (49%) in VeriChip, but divested itself of the stake in 2008. VeriChip Corporation and Steel Vault Corporate later merged to form PositiveID, and in 2010 PositiveID attempted a friendly acquisition of Digital Angel, but the bid was unanimously rejected by its board of directors.

The animal identification products subsidiary Destron Fearing was sold to Allflex USA, in July, 2011, for $25 million.

Subsidiaries
Digital Angel owns and operates Signature Communications, a distributor of two-way communications equipment in the U.K. Products offered range from conventional radio systems used by the majority of its customers, for example, for safety and security uses and construction and manufacturing site monitoring, to trunked radio systems for large-scale users, such as local authorities and public utilities.

Chief executive officers
 L. Michael Haller – appointed CEO on August 23, 2012.
 Daniel E. Penni – appointed "Interim CEO" on 1 February 2012.
 Joseph J. Grillo – former CEO of Digital Angel, beginning on January 2, 2008. Succeeding Kevin McGrath. Grillo is the former President and Chief Executive Officer of the Global Technologies Division of Assa Abloy. Randy Geissler was CEO from 2000 to 2003.

See also 
 Masonic Child Identification Programs
 PositiveID

References

External links
www.digitalangelcorp.com

Electronics companies of the United States
Companies based in Florida
Companies based in Palm Beach County, Florida
Companies established in 1993
Radio-frequency identification
Companies formerly listed on the Nasdaq
Ankerite. Ankerite, also known as brown spar () is a calcium, iron, magnesium, manganese carbonate mineral of the group of rhombohedral carbonates with the chemical formula . In composition it is closely related to dolomite, but differs from this in having magnesium replaced by varying amounts of iron(II) and manganese. It forms a series with dolomite and kutnohorite.

Name and history 
It was first recognized as a distinct species by Wilhelm von Haidinger in 1825, and named for Matthias Joseph Anker (1771–1843) of Styria, an Austrian mineralogist.

In 19th-century mineralogy, as well as in mining and among geologists, ankerite and its close analogues from the dolomite series were more often known by the capacious, expansive name of ″brown spar″. This is partly due to the fact that this mineral is the extreme (with the highest content of divalent iron ions) member of the dolomite-ankerite isomorphic series, as a result of which dirty-brown varieties of dolomite, contaminated with impurities, could also be encountered under the name of brown spar.

Properties 
The crystallographic and physical characters resemble those of dolomite and siderite. The angle between the perfect rhombohedral cleavages is 73° 48′, the hardness is 3.5 to 4, and the specific gravity is 2.9 to 3.1. The color is white, grey or reddish to yellowish brown.

Genesis 
Ankerite occurs with siderite in metamorphosed ironstones and sedimentary banded iron formations. It also occurs in carbonatites. In sediments it occurs as authigenic, diagenetic minerals and as a product of hydrothermal deposition. It is one of the minerals of the dolomite-siderite series, to which the terms brown-spar, pearl-spar and bitter-spar have been historically loosely applied.

It has been found in Western Tasmania, in mines in Dundas, Tasmania.

Image gallery

See also
List of minerals
List of minerals named after people

References

Mineral Galleries

External links

Calcium minerals
Magnesium minerals
Iron(II) minerals
Manganese(II) minerals
Carbonate minerals
Dolomite group
Trigonal minerals
Minerals in space group 148
Luminescent minerals
Al-Mishraq. Al-Mishraq, or Mishraq Sulphur State Company, is a state run sulfur plant near Mosul, Iraq.

It has twice been set alight and burned for prolonged periods. In 2003, what is thought to have been a deliberately started fire, burned for about three weeks, resulting in the largest human-made release of sulfur dioxide ever recorded. In 2016 it was set alight by ISIL and burned for seven days.

Fires
In June 2003, it was the site of the largest human-made release of sulfur dioxide ever recorded when a fire (thought to have been deliberately started) gained control and burned for about three weeks. At its height, the fire was putting 21,000 tons of sulfur dioxide a day into the atmosphere. The pollution in Mosul, which is about 45 kilometres from Mishraq, reached a catastrophic level. For over 48 hours the white smoke from sulfur dioxide could be seen in the air. Many people were taken into hospitals and most vegetation was killed.

On 22 October 2016 the plant was set alight by ISIL militants as part of the Battle of Mosul. Two civilians died and nearly 1,000 people were treated for toxic gas inhalation. Shifting winds sent the gas to Qayyarah Airfield West, where U.S. and coalition forces were forced to use gas masks. The total mass of the released sulfur dioxide was estimated to approximately 161,000 tons distributed over seven days, equivalent to a small volcanic eruption.

See also 
 Environmental issues in Iraq

References

Buildings and structures in Mosul
Environmental disasters in Asia
Environmental issues in Iraq
Kh-15. The Raduga Kh-15 or RKV-15 (; NATO: AS-16 "Kickback"; GRAU:) is a Russian hypersonic aero-ballistic air-to-ground missile carried by the Tupolev Tu-22M and other bombers. Originally developed as a standoff nuclear air-to-ground missile similar to the U.S. Air Force's AGM-69 SRAM, versions with conventional warheads have been developed.

As of early 2019, it was uncertain whether the Kh-15 was in service, with rumors that it had been retired or placed in storage.

Development
In 1967, MKB Raduga started developing the Kh-2000 as a replacement for the Kh-22 (NATO reporting name AS-4 Kitchen) heavy anti-shipping missile. Development of the Kh-15 started some time in the early 1970s. The sophistication of the design made it suitable for other roles, and a nuclear-tipped version was developed in tandem with the conventionally armed variant. An upgrade under development was cancelled in 1991, but reports in 1998 suggested an upgraded Kh-15 might be fitted to Su-35 (Flanker-E) tactical aircraft.

Design
The Kh-15 climbs to an altitude of about  and then dives in on the target, accelerating to a speed of about Mach 5.

Operational history
It entered service in 1980. It can be carried by the Su-33, Su-34, Tu-95MS-6 'Bear-H', Tu-22M3 'Backfire C', and Tu-160 'Blackjack'.

Variants
 Kh-15 (RKV-15) - the original version with nuclear warhead and inertial guidance
 Kh-15P - passive seeker for anti-radar use
 Kh-15S - active radar seeker for anti-shipping use

Operators

Current

Former
 - Passed onto successor states

Similar weapons
 KSR-5 (AS-6 'Kingfish') - heavy anti-surface missile carried under the wings of Tu-22M
 Kh-59 (AS-13 'Kingbolt') - ASM for tactical aircraft, up to 285 km range
 Kh-37 (updated version of AS-20 'Kayak') - land attack version of subsonic Kh-35 Anti-Ship missile, 250 km range
 AGM-69 SRAM - 1000 kg US missile with up to 170 km range

Photo Gallery

Notes

References
 

Kh-015
Cold War air-to-surface missiles of the Soviet Union
Cold War anti-ship missiles of the Soviet Union
Air-launched ballistic missiles
Kh-015
Kh-015
MKB Raduga products
Nuclear air-to-surface missiles
Military equipment introduced in the 1980s