omniomni/omni-engineering huggingface dataset:
Hexamethylenediamine. Hexamethylenediamine or hexane-1,6-diamine, is the organic compound with the formula H2N(CH2)6NH2. The molecule is a diamine, consisting of a hexamethylene hydrocarbon chain terminated with amine functional groups. The colorless solid (yellowish for some commercial samples) has a strong amine odor.  About 1 billion kilograms are produced annually.

Synthesis
Hexamethylenediamine was first reported by Theodor Curtius.  It is produced by the hydrogenation of adiponitrile:
NC(CH2)4CN  +  4 H2   →    H2N(CH2)6NH2
The hydrogenation is conducted on molten adiponitrile diluted with ammonia, typical catalysts being based on cobalt and iron.  The yield is good, but commercially significant side products are generated by virtue of reactivity of partially hydrogenated intermediates.  These other products include 1,2-diaminocyclohexane, hexamethyleneimine, and the triamine bis(hexamethylenetriamine).

An alternative process uses Raney nickel as the catalyst and adiponitrile that is diluted with hexamethylenediamine itself (as the solvent).  This process operates without ammonia and at lower pressure and temperature.

Applications
Hexamethylenediamine is used almost exclusively for the production of polymers, an application that takes advantage of its structure. It is difunctional in terms of the amine groups and tetra functional with respect to the amine hydrogens. The great majority of the diamine is consumed by the production of nylon 66 via condensation with adipic acid. Otherwise hexamethylene diisocyanate (HDI) is generated from this diamine by phosgenation as a monomer feedstock in the production of polyurethane. The diamine also serves as a cross-linking agent in epoxy resins.

Safety
Hexamethylenediamine is moderately toxic, with  of 792–1127 mg/kg. Nonetheless, like other basic amines, it can cause serious burns and severe irritation. Such injuries were observed in the accident at the BASF site in Seal Sands, near Billingham (UK) on 4 January 2007 in which 37 persons were injured, one of them seriously.

See also 
 1,2-Diaminocyclohexane
 2-Methylpentamethylenediamine

References

Monomers
Diamines
ESSA-8. ESSA-8 was a weather satellite launched by the National Aeronautics and Space Administration (NASA) on December 15, 1968, from Vandenberg Air Force Base, California. Its name was derived from that of its oversight agency, the Environmental Science Services Administration (ESSA).

ESSA-8 was an 18-sided polygon. It measured  in diameter by  in height, with a mass of . It was made of aluminum alloy and stainless steel covered with 10,020 solar cells. The cells charged 63 nickel–cadmium batteries, which served as a power source. The satellite could take 8 to 10 pictures every 24 hours. Each photo covered a  area at a resolution of  per pixel.

ESSA-8's mission was to replace ESSA-6, and provide detailed cloud pattern photography to ground stations worldwide.  Partners in the project included NASA, ESSA, RCA, the National Weather Service, and the National Centers for Environmental Prediction (NMC).

ESSA-8 operated for 2,644 days until it was deactivated on March 12, 1976.

References

External links

http://www.earth.nasa.gov/history/essa/essa8.html 
https://web.archive.org/web/20060902131201/http://www.met.fsu.edu/explores/Guide/Essa_Html/essa8.html

Spacecraft launched in 1968
Meteorological instrumentation and equipment
Weather satellites of the United States
Television Infrared Observation Satellites
Platform Environment Control Interface. Platform Environment Control Interface (PECI) is an Intel proprietary single wire serial interface that provides a communication channel between Intel processors and chipset components to external system management logic and thermal monitoring devices. Also, PECI provides an interface for external devices to read processor temperature, perform processor manageability functions, and manage processor interface tuning and diagnostics. Typically in server platforms, CPUs are the PECI slaves and Platform Controller Hub (PCH) is the PECI master, meanwhile in client segment, CPU is usually the PECI slave and EC/BMC is the PECI master. PECI was introduced in 2006 with the Intel Core 2 Duo microprocessors.

Support for PECI was added to the Linux kernel version 5.18 in 2022.

Thermal monitoring details 
While previous thermal management technologies have made use of thermal diodes, PECI instead uses on-die digital thermal sensors (DTS). These sensors, after being calibrated at the factory, are able to provide digital data concerning processor temperature information. The PECI bus, allowing access to this data from chipset components, is a proprietary single-wire interface with a variable data transfer speed (from 2 kbit/s to 2 Mbit/s).

From a control standpoint, the main difference between PECI and the previously used thermal monitoring methods is that PECI reports a negative value expressing the difference between the current temperature and the thermal throttle point (at which the CPU reduces speed or shuts down to prevent damage due to overheating) instead of the absolute temperature. For example, for a CPU with maximal temperature of 85 °C and a current temperature reading of 35 °C, the value reported by PECI would be −50 °C.

Advantages 
Since the value reported by PECI takes into account internal processor information about safe operating temperatures, it alleviates the need for the BIOS or operating system to make potentially incorrect assumptions about this limit. Furthermore, it supports dynamic fan control with a high degree of accuracy, where fan speed can be progressively increased as the value approaches zero.

See also 
 Host Embedded Controller Interface (HECI)
 Thermal Monitoring 2

References

Sources 
 Dual-Core Intel Xeon Processor 3000 Series Datasheet
 Dual-Core Intel Xeon Processor 5100 Series Datasheet
 Intel Core 2 Extreme X6800 and Core 2 Duo E6000 and E4000 Sequence Features

X86 architecture
Computer hardware cooling
Intel products
Compatibility (chemical). Chemical compatibility is a rough measure of how stable a substance is when mixed with another substance. If two substances can mix together and not undergo a chemical reaction, they are considered compatible. Incompatible chemicals react with each other, and can cause corrosion, mechanical weakening, evolution of gas, fire, or other undesirable interactions.

Chemical compatibility is important when choosing materials for chemical storage or reactions, so that the vessel and other apparatus will not be damaged by its contents. For purposes of chemical storage, chemicals that are incompatible should not be stored together, so that any leak will not cause an even more dangerous situation from chemical reactions. In addition, chemical compatibility refers to the container material being acceptable to store the chemical or for a tool or object that comes in contact with a chemical to not degrade. For example, when stirring a chemical, the stirrer must be stable in the chemical that is being stirred. 

Many companies publish chemical resistance charts. and databases to help chemical users use appropriate materials for handling chemicals. Such charts are particularly important for polymers as they are often not compatible with common chemical reagents; this may even depend on how the polymers have been processed. For example, 3-D printing polymer tools used for chemical experiments must be chosen to ensure chemical compatibility with care.

Chemical compatibility is also important when choosing among different chemicals that have similar purposes. For example, bleach and ammonia, both commonly used as cleaners, can undergo a dangerous chemical reaction when combined with each other, producing poisonous fumes. Even though each of them has a similar use, care must be taken not to allow these chemicals to mix.

References

External links
Chemical compatibility database

Chemical safety
USS Magnet (YDG-9). The third USS Magnet (ADG-9) was a degaussing vessel of the United States Navy, named after the magnet (the third U.S. Naval vessel to bear the name). Originally planned as a patrol craft escort (PCE-879), she was laid down on 27 May 1943 by the Albina Engine & Machine Works of Portland, Oregon; launched 30 September 1943; reclassified YDG-9 on 23 December 1943; and commissioned 10 July 1944.

Service history
Following shakedown and training out of San Pedro, Los Angeles, YDG-9 continued operations on the west coast, first for the 11th Naval District and then as a unit of ServRon 8. Later assigned to SevRon 6 to service, in close proximity, the striking forces as they moved closer to Japan, she established and operated degaussing ranges and provided facilities for inspection, calibration, and adjustment of shipboard degaussing equipment in forward areas, primarily for minesweepers. After World War II ended, she operated with mine groups at Okinawa and, after 29 January 1946 at Sasebo, Japan as those groups cleared the waters to allow safe passage to both military and merchant shipping.

Returning to the United States later in the year, she decommissioned 11 December 1946 at San Diego where she remained berthed, into 1969, as a unit of the Pacific Reserve Fleet. After entering the Reserve Fleet, YDG-9 was reclassified ADG-9 on 1 November 1947, and named Magnet on 1 February 1955, the third U.S. Navy ship of the name.
 
Struck from the Naval Register on 21 February 1975, Magnet was sunk as a target on 4 March 1976 off the coast of Baja California, Mexico at  at a depth of .

References

 
 

World War II auxiliary ships of the United States
Degaussing ships of the United States Navy
Ships built in Portland, Oregon
1943 ships
Ships sunk as targets
Maritime incidents in 1976
Shipwrecks of the California coast
Presentation logic. In software development, presentation logic is concerned with how business objects are displayed to users of the software, e.g. the choice between a pop-up screen and a drop-down menu. The separation of business logic from presentation logic is an important concern for software development and an instance of the separation of content and presentation.

One major rationale behind "effective separation" is the need for maximum flexibility in the code and resources dedicated to the presentation logic. Client demands, changing customer preferences and desire to present a "fresh face" for pre-existing content often result in the need to dramatically modify the public appearance of content while disrupting the underlying infrastructure as little as possible.

The distinction between "presentation" (front end) and "business logic" is usually an important one, because:
 the presentation source code language may differ from other code assets;
 the production process for the application may require the work to be done at separate times and locations;
 different workers have different skill sets, and presentation skills do not always coincide with skills for coding business logic;
 code assets are easier to maintain and more readable when disparate components are kept separate and loosely coupled;

References

Software design
Software architecture
Software engineering terminology
Neat. Neat may refer to: 

 Neat (bartending), a single, unmixed liquor served in a rocks glass
 Neat, an old term for horned oxen
 Neat Records, a British record label
 Neuroevolution of augmenting topologies (NEAT), a genetic algorithm (GA) for the generation of evolving artificial neural networks
 Non-exercise activity thermogenesis, a concept in human energy expenditure

See also
 Neet (disambiguation)
 NEAT (disambiguation)
 "Neat Neat Neat"
 Neate, a surname
 Neat Volume
Application Control Management System. Application Control Management System (Application Control and Management System) (ACMS) is a transaction processing monitor software system for computers running the OpenVMS operating system.

ACMS was developed by Digital Equipment Corporation in the early 1980s as part of an effort to gain market share in commercial applications. (Digital's initial strength was in scientific computing.) ACMS was originally released in 1984 as part of the integrated VAX Information Architecture product set along with Rdb (relational database system), DBMS (CODASYL database system), TDMS (original forms system), DECforms (a newer forms system), CDD (Common Data Dictionary), and DATATRIEVE (query and report writer for record-oriented files and databases). ACMS pioneered many transactional RPC and abstraction concepts, and remains a popular TP monitor for the OpenVMS environment.

External links 
 ACMS Product Page

OpenVMS software
Transaction processing
Exploratory programming. Exploratory programming, as opposed to implementation (programming), is an important part of the software engineering cycle: when a domain is not very well understood or open-ended, or it's not clear what algorithms and data structures might be needed for an implementation, it's useful to be able to interactively develop and debug a program without having to go through the usual constraints of the edit-compile-run-debug cycle. Languages such as APL, Cecil, Clojure, C#, Dylan, Factor, Forth, F#, J, Java, Julia, Lisp, Mathematica, Obliq, Oz, Prolog, Python, REBOL, Perl, R, Ruby, Scala, Self, Smalltalk, Tcl, and JavaScript, often in conjunction with an IDE, provide support for exploratory programming via interactivity, dynamicity, and extensibility.

Formal specification versus exploratory programming

For some software development projects, it makes sense to do a requirements analysis and a formal specification. For other software development projects, it makes sense to let the developers experiment with the technology and let the specification of the software evolve depending upon the exploratory programming.

Similarity to Breadboarding
A similar method of exploration is used in electronics development, called Breadboarding, in which various combinations can quickly be tried and revised, accepting the tradeoff that the result is definitely temporary in nature.

See also
 Live coding
 Software Prototyping

Notes

References

Programming paradigms
User interface techniques
Robert H. Perry. Robert H. Perry (1924–1978) was the second editor of the popular reference work Perry's Chemical Engineers' Handbook, originally edited by his father, John H. Perry, with the first edition published in 1934.

Perry taught at the University of Oklahoma from 1958 to 1964, and was department director of Chemical Engineering from 1961 to 1963. He also taught at the University of Rochester and the University of Delaware. With Sidney D. Kirkpatrick and Cecil H. Chilton, Perry supervised the production of the 4th edition, published in 1963. Perry and Chilton together edited the 5th edition, released early in 1973.

Don W. Green was chosen to edit the 6th edition, after Chilton's death from heart disease. Perry was a doctoral adviser to Green.

During this editorial process, Perry was killed as a pedestrian when struck by a car in England in 1978.

References

University of Oklahoma faculty
1924 births
1978 deaths
20th-century American engineers
University of Delaware faculty
University of Rochester faculty
Ethanedisulfonic acid. Ethanedisulfonic acid is a diprotic sulfonic acid, with pKa values of -1.46 and -2.06, making it a very strong acid.  When used in pharmaceutical formulations, the salts with the active ingredient are known as edisylates.

See also
Methanedisulfonic acid
1,3-Propanedisulfonic acid
Isethionic acid

References

Sulfonic acids
1,2-Ethanediyl compounds
List of dump truck manufacturers. List of dump truck manufacturers.

Tractor units

 Ashok Leyland
 BelAZ
 BEML India Ltd
 CAMC
 Chevy
 DAF CF, 95 XF
 Davis Trailer & Equipment
 Dongfeng Liuqi
 Ford
 GAZ
 GMC
 HEPCO
 Hino Motors (Toyota)
 Leader Trucks
 International
 Isuzu
 Iveco Eurotrakker, Eurostar
 KamAZ
 Kenworth
 Kress Corporation:200CII.
 Mack
 MAN
 MAZ
 Mahindra
 Mercedes-Benz Actros, Axor
 Micro-Vett
 Mitsubishi Fuso Truck and Bus Corporation
 MoAZ
 Peterbilt
 Perlini
 Renault Trucks
 ROMAN
 Scania AB 220, 340, 360, 460
 SISU
 ST Kinetics
 Sterling Trucks
 Tata Motors
 Tata Daewoo
 TBEI
 Tonar
 UD
 Ural Automotive Plant
 Volvo FH12 and Volvo FM12

Semi-trailer

 Schmitz Cargobull
 Seri Zenith
 Voltrailer
 Wielton

See also
Dump truck
Tractor unit
Semi-trailer and semi-trailer truck
List of American truck manufacturers

External links

Manufacturers
 Dump truck
Truck-related lists
Dump truck
HD Tach. HD Tach is a software program for Microsoft Windows (2000 or XP) that tests and graphs the sequential read, random access and interface burst speeds of attached storage devices (hard drive, flash drive, removable drive etc.). Drive technologies such as SCSI, IDE/ATA, IEEE 1394, USB, SATA and RAID are supported.

A prominent feature of the software was an included library of drive benchmarks, as well as the option to save your own drive's benchmarks locally or submit them to an online database. The company's website also had a forum with over 2000 user posts.

On December 5, 2011, citing the lack of time to devote to the project, Simpli Software formally announced on its website that HD Tach had reached end-of-life and was no longer being supported. The domain has since expired.

The latest version of this application (3.0.4.0) is not fully compatible with Windows Vista, Windows 7, or Windows 8. However, HD Tach works in these operating systems by running it in Windows XP SP2 or SP3 compatibility mode. HD Tach 2.70 is the last version to work on Windows NT 4.0.

History 
HD Tach was originally developed by TCD Labs, Inc. In 2000 the company was acquired by Oak Technology, Inc. Simpli Software, Inc. was formed by the original group of TCD Labs employees and acquired all rights to the benchmarks and source code from Oak Technology in 2003. The domain name displayed in the software, simplisoftware.com, began resolving to a domain reseller landing page in November 2012.

Bibliography

References 

Benchmarks (computing)
Storage software
Utilities for Windows
Mansfield and District Light Railways. Mansfield & District Light Railways was an electric tramway network operating in Mansfield from 16 July 1905 to  9 October 1932. The tramway company was a subsidiary of Midland Counties Electric Supply Company, who in turn were owned by Balfour Beatty.

History
On 18 November 1904, Mansfield Town Council concluded negotiations with the company promoting the tramway and authorised the start of construction.

The Pleasley and Nottingham Road sections of the Mansfield and District Light Railways were completed and inspected by General Trotter and Major Pringle of the Board of Trade on 11 July 1905 and opened for passenger traffic on the same day.

The service from Mansfield to Sutton was authorised to start on 21 December 1905

Infrastructure

The tramway network consisted of 5 routes covering just over 12 miles and joining neighbouring towns. 
These routes began in Mansfield's Market Place and went to Berry Hill, Crown Farm, Mansfield Woodhouse, Pleasley and via Sutton-in-Ashfield to Hucknall-under-Huthwaite.

The depot was in Sutton Road, Mansfield at . The buildings and site are still in use as a motorbus depot.

Tramcars

The fleet comprised a total of 31 cars plus a water car. Livery was red and cream (light green and cream in later years). Two cars were purchased in 1912 from the Cavehill and Whitewell Tramway of Northern Ireland and two bought and one borrowed in 1930 from the nearby Nottinghamshire and Derbyshire Tramways Company, (another Midland Counties Electric Supply Co. subsidiary).

Closure

The tramway was largely rural in nature and it was replaced by motor buses, despite trolleybus authority having been obtained in 1929. 

In 1932 two trams (27 and 28) were sold to Sunderland Corporation Tramways, where they saw further service until 1953.

References

External links
 Mansfield & District Light Railways uniformed staff
 Mansfield & District Light Railways button

Rail transport in Nottinghamshire
Tram transport in England
Railway companies established in 1905
Mansfield
British companies established in 1905
Wilfred Stokes. Sir Frederick Wilfrid Scott Stokes,  (9 April 1860 – 7 February 1927)  was the inventor in 1915 of the Stokes Mortar, which saw extensive use in the latter half of the First World War and was one of the first truly portable mortars.

Stokes was born on 9 April 1860 in Liverpool, the son of Scott Nasmyth Stokes, a school inspector. He was educated at St. Francis Xavier's College and the Catholic University College, Kensington.

Following an apprenticeship with the Great Western Railway, he eventually became an assistant to William Shelford working on the designs for bridges for the Hull and Barnsley Railway.

He was involved with the construction of the Aswan Low Dam in Egypt, for which he in 1902 received the 2nd class of the Ottoman Order of Osmanieh from the Khedive of Egypt.

A civil engineer by trade, Stokes was appointed chairman and managing director of Ransomes & Rapier, an engineering company based in Ipswich, which manufactured cranes. Between 1915 and 1918 Stokes worked for the Inventions Branch of the Ministry of Munitions where he invented the Stokes Mortar. The trench mortar was first used in 1915 during the Battle of Loos to fire a smoke shell. At first it was not liked but as the construction was improved it was widely used and eventually produced in two sizes.  This mortar continued in use, its effectiveness being improved again and again by other British engineers.

Stokes received a knighthood in 1917 for inventing the mortar which was named for him. He was also given several forms of monetary reward by the Ministry of Munitions for his invention including royalties of £1 per Stokes mortar bomb.

Stokes married Iren Ionides in 1899. He is buried at St Mary Magdalen Roman Catholic Church, Mortlake.

His brother Leonard Stokes was an architect. His nephew Richard Stokes was a Labour MP and minister.

See also
Stokes Mortar

References

External links

1860 births
1927 deaths
British people of World War I
British inventors
English civil engineers
Knights Commander of the Order of the British Empire
Engineers from Liverpool
Weapon designers
Burials at St Mary Magdalen Roman Catholic Church Mortlake
List of surviving Douglas A-26 Invaders. The A-26 Invader (B-26 between 1948–1965) was a twin-engined light attack bomber, built by the Douglas Aircraft Co. during World War II, that also saw service during several other conflicts in the post-war era of the latter 20th century.

Surviving aircraft

These complete examples of the A-26 Invader have been preserved or restored, and are on display at museums or at military bases, or are active aircraft potentially viewable at air events.

Status Codes:

D = Display
A = Airworthy
S = Stored
R = Under restoration

References

Notes

Bibliography

Federal Aviation Administration. 2014. United States Civil Aircraft Register (USCAR) 

(CD-ROM)

External links
Douglas B-26K (A-26) Counter Invader – National Museum of the United States Air Force
Warbird Registry: A-26 Registry http://www.warbirdregistry.org/a26registry/a26registry.html

A-26 survivors
Douglas A-26 Invaders
Filtered air positive pressure. A filtered air positive pressure environment in laboratory animal science is a space that is under positive pressure with respect to the outside world. In this way, no germs that could affect the lab animals or that are a threat to the SPF status can enter the facility. To bring in new air, high efficiency particulate air filters (HEPA) are used.

In some facilities, the opposite is done: negative pressure inside prevents escape of germs to the outside world. This is done when the facility does research on dangerous germs like anthrax.

Next to these obvious things, these facilities can have other special hygiene control elements:
air locks for personnel, feed, bedding, cages and materials (e.g. autoclave with two doors, one to the inside, one to the outside) 
showers for personnel
emergency power generator or uninterruptible power supplies

References

Pressure
Animal testing