omniomni/omni-engineering huggingface dataset:
Magnetic nano. A magnetic nano (often shortened to just nano) is a small metal container, measuring a centimetre in height and width, with a screw-top lid and a thin, cylindrical magnet at its base. 
They often have an O-ring seal between the lid and the body to make them easier to open and partially waterproof.

Original use
Magnetic nanos were originally manufactured in 2001 to store flashing LED lights for use as jewellery, giving them the colloquial name 'blinkies'. The LED went inside the lid, with two button batteries inside the nano's tube and a rare-earth magnet at the base, so the nano could attach to clothing and jewellery.

Use as geocache containers 

When it was discovered that magnetic nanos can be used as geocache containers, they were quickly mass-produced and sold for that purpose. They are widely known in the geocaching community as one of the smallest geocache containers. 

Magnetic nano geocaches only contain a thin, rolled-up paper sheet for geocachers to sign their username initials on.

Popularity
Due to their very small size, they have become especially popular in urban locations (particularly cities), allowing for geocaches to easily be hidden in these areas. With larger geocaches, there are limitations to where urban geocaches can be well hidden without raising alarm. Magnetic nanos, however, are often too small to be noticed and their magnetic nature means they can attach to, and blend in with, the vast majority of urban metallic structures such as benches, metal fences/railings and road signs.

Size Classification
Some geocache listing websites, such as Geocaching.com, don't have 'nano' as a size to select from when creating a cache listing, so geocachers are advised to list nano geocaches as 'micro', as they are less than 10 millilitres in volume

Some geocachers believe that 'nano' should be a separate size to 'micro' due to their noticeable size difference, so use the 'other' or 'not specified' size option.

Issues
Magnetic nanos are not completely weatherproof, even with an O-ring seal, and this can present some issues:

The paper log sheets inside nanos can sometimes become jammed and difficult to extract and roll back up, particularly if water has entered the nano. As a result, it is recommended that geocachers bring tweezers if they are finding nano caches and this is usually written on the geocache's webpage. Also, in cold conditions, if no rubber seal is present, then the nano can freeze and become difficult to open.

References 

Containers
Geocaching
Types of magnets
Rankine half body. In the field of fluid dynamics, a Rankine half body is a feature of fluid flow discovered by Scottish physicist and engineer William Rankine that is formed when a fluid source is added to a fluid undergoing potential flow. Superposition of uniform flow and source flow yields the Rankine half body flow. A practical example of this type of flow is a bridge pier or a strut placed in a uniform stream. The resulting stream function () and velocity potential () are obtained by simply adding the stream function and velocity potential for each individual flow.

Solution 

The flow equations of the Rankine half body are solved using the principle of superposition, combining the solutions of the linear flow of the stream and the circular flow of the source.

Given the linear flow field  and the source , we have

 
 

The stagnation point for this flow can be determined by equating the velocity to zero in either directions. Because of symmetry of flow in y-direction, stagnation point must lie on x-axis.

Equating both  and  to zero, we obtain .

At  and  we have stagnation points.

Now, we note that , so following this constant streamline gives the outline of the body:

Then,  describes the half body outline.

Significance
This type of flow provides important information about flow in front part of streamlined body. It is probable that at the boundary, flow is not properly represented for real flow. The pressure and velocity of flow near to boundary layer is calculated by applying the Bernoulli's principle and is approximated with potential flow. The above equations may be used to calculate the stress on the body placed into the flow stream.

See also 
 Rankine body

References 
 http://www.iust.ac.ir/files/mech/mazidi_9920c/fluid_ii/lecture8.pdf (pg no 22.23)
 http://www-mdp.eng.cam.ac.uk/web/library/enginfo/aerothermal_dvd_only/aero/fprops/poten/node35.html
 http://nptel.ac.in/courses/101103004/15
 http://poisson.me.dal.ca/site2/courses/mech3300/Superposition.pdf
 https://faculty.poly.edu/~rlevicky/Files/Other/Handout14_6333.pdf
 http://web.mit.edu/2.016/www/handouts/2005Reading4.pdf
 http://www1.maths.leeds.ac.uk/~kersale/2620/Notes/chapter_4.pdf

Fluid dynamics
Biometrology. Biometrology refers to measurement and data activities that provide quantitative characterization of biology. Biometrology advances laboratory techniques regarding scalable bioproducts or services.

Biometrology products
 BioBricks Foundation is charting a technical standards framework that will serve as the driver and promoter of a high-quality, technical-standards process for synthetic biology based on BioBrick™ parts.

 The Genome in a Bottle Consortium is a public-private-academic consortium hosted by NIST to develop the technical infrastructure (reference standards, reference methods, and reference data) to enable translation of the whole human genome sequencing to clinical practice. The priority of Genome in a Bottle is authoritative characterization of human genomes for use in analytical validation and technology development, optimization, and demonstration.

 Characterization of relative activities of a reference collection of BioBrick promoters in order to further support adoption of RPU-based measurement standards.

See also
 Metrology

References

Metrology
Portland Cement Association. Portland Cement Association is a non-profit organization that promotes the use of cement and concrete. The organization conducts and sponsors research, participates in setting cement manufacturing standards, and disseminates free designs of concrete-based architectural structures, among other functions.

History 

PCA's origin dates back to 1902, following a meeting of cement manufacturers in the eastern U.S. who assembled to discuss problems with cement packaging. At the time, cement was packaged in reusable cloth sacks that were returned to the manufacturer, but that created problems for consumers. On October 1, 1902, this issue prompted the formation of a temporary organization that would represent all the manufacturers involved. The organization was unofficially called "the Eastern Portland Cement Manufacturers." The organization was formally established and its constitution and by-laws adopted by the representatives of 20 cement companies in New York on October 23, 1902, and renamed the Association of Portland Cement Manufacturers.

In 1916, as the Association entered into a contract with the Lewis Institute to conduct joint research in concrete, it was renamed again to the Portland Cement Association, and its headquarters moved from Philadelphia to Chicago.

See also 
 American Concrete Institute

References

Literature cited

External links 
 

American engineering organizations
Trade associations based in the United States
Organizations based in Illinois
Organizations established in 1902
Cement industry
ET-188. ET-188 was an IBM PC XT compatible computer made by the Yugoslav company Novkabel (Novosadska fabrika kabela - Novi Sad Cable Factory) from Novi Sad (now Serbia) in the 1980s.

Novkabel already had experience in developing computer systems (ERA 20, ERA 60 and others) which was used to make ET-188 as an original design, compatible with IBM PC XT. 

To save space and to lower the cost, ET-188 used 8 MHz Intel 80188 CPU, with integrated timer, DMA and interrupt controller. This also made it faster than the original XT.
ET-188 was offered to the public in 1985 and advertised in the Yugoslav computer press.

An improved ET-188A model was in May 1986 presented to the public at the Belgrade International Fair of Technique and Technical Advancements with more RAM and a new redesigned case.
Among other things, ET-188A was used for education in classrooms throughout Vojvodina province.

Technical specifications
 CPU: Intel 80188 running at 8 MHz
 ROM: 8 KB custom made BIOS
 RAM: 256KB (ET-188) or 512 KB (ET-188A), expandable up to 640 KB
 Operating system: MS-DOS 3.20
 Secondary storage: 2 x 5.25’’ 360KB floppy drive or 5.25’’ 360KB floppy drive + 22MB Tandon hard disk
 Display: CGA or Hercules compatible adapter
 Sound: beeper
 I/O ports: DE9 video output, RS-232, parallel port, keyboard

References 

IBM PC compatibles
Trellis-Owl. Trellis/Owl, or simply Owl, is a defunct object-oriented programming language created by Digital Equipment Corporation. It was part of a programming environment, Trellis. It ran on the OpenVMS operating system.

Trellis/Owl differed from contemporary languages in several ways. For one, it did not use dot notation for method calls on objects, and used a traditional functional style instead, which they referred to as operations. Operations were supported by the concept of a controlling object, the first parameter in the function call, which indicated which class was being referred to. Whereas most OO languages of the era might have a myStringVariableToPrint.print() method, in Trellis/Owl this would be print(myStringVariableToPrint), and the print method of the class String would be called based on a string being the first parameter. Trellis/Owl also supported properties, which they referred to as components. Trellis/Owl also included a system allowing the easy creation of iterators, using the yields keyword to replace returns in the definition of an operation. yields indicates the operator will return a series of values instead of one.

Notes

References

Citations

Bibliography
 
 
 

Programming languages
Walter Mars I. The Walter Mars I was a nine-cylinder, air-cooled, radial engine for aircraft use built in Czechoslovakia in the late 1920s.

Design and development
The Mars I was the largest capacity design of a series of three similar radial engines developed by the Walter company. Common cylinders were used for the five-cylinder Walter Vega and the seven-cylinder Walter Venus, the Mars I being a nine-cylinder engine.

Applications

ANBO III
Breda Ba.15
DAR 4
DAR 6
Fizir FN
Focke-Wulf A 33
Letov Š-32
SET 10

Specifications

See also

References

Mars I
1920s aircraft piston engines
Aircraft air-cooled radial piston engines
1,3-Difluoro-trisulfane-1,1-difluoride. 1,3-Difluoro-trisulfane-1,1-difluoride is an inorganic molecular substance with the structure SF3SSF, consisting of sulfur in a low oxidation state with fluorine. The compound consists of a chain of three sulfur atoms, with three fluorine atoms bonded to the sulfur on one end and the fourth fluorine bonded to the sulfur on the other end. It has a melting point of -62 °C and a boiling point of 94 °C. As a gas, it is unstable and breaks up to form SSF2 and SF4.

SF3SSF is produced by the condensation of sulfur difluoride and an isomer of SSF2. The reaction S3F4  SSF2 + SF2 uses 6 kJ/mol.

Possible isomers of its S3F4 molecular formula include FSSF2SF, which has a spontaneous fluorine migration to yield F2SSSF2, which in turn spontaneously fragments to give SF2 and SSF2.

References

Sulfur fluorides
Kanu Gandhi (scientist). Kanu Gandhi (1928 – 7 November 2016) was an Indian scientist and son of Ramdas Gandhi, thus a grandson of Mahatma Gandhi.

He studied at Massachusetts Institute of Technology, graduating with a master's degree in civil engineering in 1963. Later he worked for NASA and United States Department of Defense on aircraft design. He moved back to India with his wife in 2014. Gandhi died in a private hospital in Surat.

Career 
In 1963, Gandhi graduated from the Massachusetts Institute of Technology with a master's degree in civil engineering. Later he worked for NASA and United States Department of Defense on aircraft design. His wife Shivalaxmi was a professor and researcher in Boston Biomedical Research Institute. They had no children. In 2014 they moved back to India. He died in a private hospital in Surat.

References

2016 deaths
1928 births
Scientists from Gujarat
Kanu
American people of Indian descent
People from Surat
China Academy of Aerospace Electronics Technology. China Academy of Aerospace Electronics Technology (), was founded in 1965. It is an indirect shareholder of listed company ZTE (via ZTE Holdings) as well as the largest shareholder of China Aerospace Times Electronics (), the second largest shareholder of Shaanxi Aerospace Power Hi-Tech (). The research institute is a subsidiary of China Aerospace Science and Technology Corporation.

External links
 

Research institutes in China
Government agencies of China
1965 establishments in China
Albatros L 83 Adler. The Albatros L 83 Adler was a small, fast transport aircraft for passengers, mail or other cargo, flown in Germany in 1931. Two were built.

Design and development

The Adler (Eagle) was designed to be a fast, light transport aircraft, carrying payloads of  over distances of around . It had thick section, low-set, high aspect ratio (10.8) wings and was powered by a  Junkers L5 six-cylinder liquid-cooled inline engine.

The wing was in three parts, with a very short, rectangular plan centre-section built into the fuselage structure and containing the fuel tanks.  Its ends were braced on each side with pairs of streamlined steel struts to the upper fuselage. Long-span cantilever outer panels were strongly straight-tapered in plan and also tapered in thickness from below, giving the Adler 4° of dihedral. The wings were built around pairs of trellis type spars and covered with corrugated duralumin. High aspect ratio ailerons filled the outer halves of the trailing edges.

The fuselage of the fuselage was based on a cross-braced, rectangular section steel frame. Its Junkers L5 engine was mounted in the nose and neatly cowled, with its oil tank aft of a firewall and a retractable honeycomb radiator on the fuselage underside.  The region behind the engine contained an enclosed cockpit over the leading edge and a cabin which extended back to the trailing edge; the sides of this part of the fuselage were dural covered and its slightly shaped upper and lower surfaces canvas covered. The rear fuselage was entirely canvas covered.  The cockpit contained two side-by-side seats provided with dual controls and was accessed via the cabin. This was a space  long,  wide and  high, which could seat four, each with their own window, or be used to carry freight or mail. Aft of the cabin there was a small entry lobby with a port-side door and a facing, enclosed, toilet.

The Adler did not have a conventional fin but the in-flight adjustable tailplane was mounted above the fuselage on a small, thin aerofoil-section step with its rear underside cut-away, and braced from below with a single strut on each side. The one-piece elevator was aerodynamically balanced.  The rudder, also balanced, was hinged from the rear fuselage and the rear of the step.

Its tailskid  landing gear was fixed, with each mainwheel on its own bent axle from the central fuselage underside and with drag struts back to the lower fuselage frames. Short, near vertical, rubber shock absorber legs stood between the wheels and the forward spar at the extreme edge of the wing centre section. The tailskid was a steel tube with a wooden shoe.

Operational history

The exact date of the first flight of the Albatros L.83 Adler is unknown but was in the first half of 1931. Two were built. The history of the first (D-2024) is not known but the second (D-2211) was registered to the Deutsche Verkehrsfliegerschule (DVS) transport flying school in February 1932.

Operators

 DVS

Specifications

References

1930s German civil utility aircraft
L 083 Adler
Low-wing aircraft
Single-engined tractor aircraft
Aircraft first flown in 1931
Thomas Chan. Thomas Shun-Kuei Chan (; born 3 January 1964) is a Taiwanese lawyer and politician. He was deputy minister of the Environmental Protection Administration between 20 May 2016 and 8 October 2018.

Education
Chan obtained his bachelor's degree in law from National Taiwan University in 1985. He then worked as an environmental lawyer.

Taitung Miramar Resort case
Thomas Chan is known for his volunteer (pro bono) work on the build–operate–transfer (BOT) Taitung Miramar Resort case. 
 On 23 December 2008, in conjunction with community plaintiffs (including indigenous land rights activist, Lin Shu-ling) and Wild at Heart Legal Defense Association,  Chan challenged the validity of an environmental impact assessment (EIA) retrospectively conducted by the Taitung County Government in relation to the Taitung Miramar Resort.  This case would ultimately lead to Supreme Court rulings barring Miramar from opening. Chan has called for the resort to be demolished.

Political career
Chan was a member of Environmental Impact Assessment Review Committee of the EPA in 2005–2007, member of National Planning Commission and member of Regional Planning Committee of the Ministry of the Interior in 2007-2011 and 2009-2011 respectively, member of Trust Law Amendment Study Sub-committee of the Ministry of Justice in 2010-2016 and member of Legal Affairs Committee of the Council of Indigenous Peoples in 2011–2016. Chan assumed office as deputy minister of the Environmental Protection Administration in May 2016. He tendered his resignation for the first time soon after Lin Chuan left the premiership in September 2017. A year later, Chan notified the Executive Yuan that he intended to resign. His second resignation was not accepted until October 2018, when Chan posted about it on social media.

References

3. Lin, Chia-nan. 
"INTERVIEW: EPA’s Chan addresses wind farms." {http://www.taipeitimes.com/News/taiwan/archives/2017/08/07/2003676080}

External links
 

1964 births
Living people
National Taiwan University alumni
20th-century Taiwanese lawyers
Ministers of environment of Taiwan
21st-century Taiwanese lawyers
Trifluoramine oxide. Trifluoramine oxide or Nitrogen trifluoride oxide (F3NO) is an inorganic molecule with strong fluorinating powers.

Production
Trifluoramine oxide was first discovered in 1966 independently by two different groups. One way to produce it was by an electric discharge in a mixture of oxygen on nitrogen trifluoride. Another even less yielding method is by reacting noble metal fluorides (IrF6 or PtF6) with nitric oxide. It is separated by distillation, and can be purified by treating it with potassium hydroxide solution which reacts with the other fluorine containing molecules produced.

An alternate way to produce it is by burning nitric acid in fluorine, followed by rapid cooling. Yet another way is the photochemical reaction of fluorine and nitrosyl fluoride: F2 + FNO → F3NO.  This reaction can also happen with heat, but hot fluorine is hard to contain without a reaction with the container. yet another production route is to thermally decompose nitrosyl hexafluoronickelate (NO)2NiF6 → ONF + ONF3 + NiF2.

Properties
F3NO is a colourless gas at standard conditions. It has a critical temperature of 29.5 °C where the density is 0.593 g/cm3. Critical pressure is about 64 atmospheres.

Trifluoramine oxide has a Trouton's constant of 20.7. Heat of vapourisation at the boiling point is 3.85 kcal/mol.

The F3NO molecule has C3V symmetry, with all the N-F bonds being equivalent.  The shape is almost a tetrahedron as N-O bond is similar to the N-F bonds in nature.
The nuclear magnetic resonance (NMR) spectrum of 19F has a triplet line around −363 ppm. JNF is 136 Hz.
The infra red spectrum N-O stretch at 1687 cm−1, N-F stretch at 743 cm−1, unsymmetrical N-F stretch 887 cm−1 ∠ONF bend 528 cm−1, wither other bands at 558, 528, 801, 929, 1055, 1410, 1622, 1772, 2435, and 3345 cm−1. The dipole moment is 0.0390 D.

The N-O bond has 75% double bond character.  This differs from the amine oxides where the amine is much more basic and with a positive charge. The N-O bond-length is 1.158 Å; the N–F bond-length is  1.431 Å ; the bond angles ∠FNF  is  101°; and the three bond angles ∠ONF = 117.

Trifluoramine oxide is toxic, killing rats at a concentration between 200 and 500 ppm.

Reactions
On fluorinating other compounds nitrosyl fluoride (NOF) is formed.
Trifluoramine oxide does not react with water, glass or nickel, making it easier to handle.
The "adducts" formed with the pentafluorides, are actually hexafluoride salts containing the F2NO+ ion.

Trifluoramine oxide reacts slowly with mercury, producing mercury fluorides, and nitrogen oxides. Trifluoramine oxide is fairly stable when heated to 300 °C but slowly breaks up to fluorine and NO2F, NOF, NO2 and NO. The oxygen remains attached to the nitrogen during decomposition.

References

Nitrogen oxohalides
Nitrogen(V) compounds
Oxyfluorides
Institute for Scintillation Materials. Institute for Scintillation Materials of NAS of Ukraine is a Ukrainian leading research centre specializing in luminescent and scintillation materials research and development and can be ranked in the top of the European and international research organizations working in the area of radiation detection.

Main scientific directions
 scintillation and luminescent environment materials science;
 fundamental researches of radiation and matter interaction;
 the technologies and nano-technologies development on scintillation detectors production and production of devices on their basis.

External links
 Official web site

Research institutes in Ukraine