omniomni/omni-engineering huggingface dataset:
Transpiration stream. In plants, the transpiration stream is the uninterrupted stream of water and solutes which is taken up by the roots and transported via the xylem to the leaves where it evaporates into the air/apoplast-interface of the substomatal cavity. It is driven by capillary action and in some plants by root pressure. The main driving factor is the difference in water potential between the soil and the substomatal cavity caused by transpiration.

Transpiration 

Transpiration can be regulated through stomatal closure or opening. It allows for plants to efficiently transport water up to their highest body organs, regulate the temperature of stem and leaves and it allows for upstream signaling such as the dispersal of an apoplastic alkalinization during local oxidative stress.

Summary of water movement:
Soil
Roots and Root Hair
Xylem
Leaves
Stomata
Air

Osmosis 

The water passes from the soil to the root by osmosis. The long and thin shape of root hairs maximizes surface area so that more water can enter. There is greater water potential in the soil than in the cytoplasm of the root hair cells. As the cell's surface membrane of the root hair cell is semi-permeable, osmosis can take place; and water passes from the soil to the root hairs.
The next stage in the transpiration stream is water passing into the xylem vessels. The water either goes through the cortex cells (between the root cells and the xylem vessels) or it bypasses them – going through their cell walls.
After this, the water moves up the xylem vessels to the leaves through diffusion: A pressure change between the top and bottom of the vessel. Diffusion takes place because there is a water potential gradient between water in the xylem vessel and the leaf (as water is transpiring out of the leaf). This means that water diffuses up the leaf. There is also a pressure change between the top and bottom of the xylem vessels, due to water loss from the leaves. This reduces the pressure of water at the top of the vessels. This means water moves up the vessels.
The last stage in the transpiration stream is the water moving into the leaves, and then the actual transpiration. First, the water moves into the mesophyll cells from the top of the xylem vessels. Then the water evaporates out of the cells into the spaces between the cells in the leaf. After this, the water leaves the leaf (and the whole plant) by diffusion through stomata.

See also
 Soil plant atmosphere continuum for modelling plant transpiration.

References
Felle HH, Herrmann A, Hückelhoven R, Kogel K-H (2005) Root-to-shoot signalling: apoplastic alkalinization, a general stress response and defence factor in barley (Hordeum vulgare). Protoplasma 227, 17 - 24.
Salibury F, Ross C (1991) Plant Physiology. Brooks Cole, pp 682, .

Plant physiology
Emagram. An emagram is one of four thermodynamic diagrams used to display temperature lapse rate and moisture content profiles in the atmosphere. The emagram has axes of temperature (T) and pressure (p). In the emagram, the dry adiabats make an angle of about 45 degrees with the isobars, isotherms are vertical and isopleths of saturation mixing ratio are almost straight and vertical.

Usually, temperature and dew point data from radiosondes are plotted on these diagrams to allow calculations of convective stability or Convective Available Potential Energy (CAPE). Wind barbs are often plotted at the side of a tephigram to indicate the winds at different heights.

First devised in 1884 by Heinrich Hertz, the emagram is used primarily in European countries. Other countries use similar thermodynamic diagrams for the same purpose. However, the details of their construction vary. Emagram is the first atmospheric thermodynamic diagram.

See also
Thermodynamic diagrams
Skew-T log-P diagram
Tephigram
Stüve diagram

References
 Thermodynamic diagrams

Bibliography
 
 

Atmospheric thermodynamics
IBM LPFK. The Lighted Program Function Keyboard (LPFK) is a computer input device manufactured by IBM that presents an array of buttons associated with lights.
Each button is associated to a function in supporting software, and according to the availability of that function in current context of the application, the light is switched on or off, giving the user a graphical feedback on the set of available functions. Usually the button to function mapping is customizable.

External links 
 http://brutman.com/IBM_LPFK/IBM_LPFK.html

Computer keyboards
LPFK
Sendzimir process. Sendzimir process (named after Tadeusz Sendzimir) is used to galvanize a steel strip by using a small amount of aluminum in the zinc bath and producing a coating with essentially no iron-zinc alloy. The process guarantees high resistance and durability characteristics. About 75% of hydrogen was needed in the original Sendzimir process but all the newer nonoxidizing methods of degreasing require only 7–15%. 

The rolling of hot steel slabs using a Sendzimir mill requires a much smaller operational area than a continuous hot strip mill.
This milling process is not recommended for heavy duty running surfaces such as crane rail.

See also
Hot-dip galvanizing
Jewelling
Phosphate conversion coating
Quench polish quench

References

Corrosion prevention
Steel
Polish inventions
Hans Hellmann. Hans Gustav Adolf Hellmann (14 October 1903 – 29 May 1938) was a German theoretical physicist.

Biography
Hellmann was born in Wilhelmshaven, Prussian Hanover. He began studying electrical engineering in Stuttgart but changed to engineering physics after a semester. Hellmann also studied at the University of Kiel.

He received his diploma from the Kaiser Wilhelm Institute for Chemistry in Berlin for work on radioactive compounds under Otto Hahn and Lise Meitner. He received his Ph.D. at Stuttgart with Prof. Erich Regener for work on the decomposition of ozone. Hellmann's future spouse Victoria Bernstein was the foster daughter of Regener. In 1929 Hellmann became an assistant professor at the Leibniz University Hannover.

After the Nazi rise to power, Hellmann was dismissed on 24 December 1933 as ‘undesirable’ because of his Jewish wife. He immigrated to the Soviet Union, taking up a position at the Karpov institute in Moscow working among other things on pseudopotentials. However, he was later denounced during the Great Purge, imprisoned on 10 May 1938 and executed in Butovo on 29 May. His son, Hans Hellmann, Jr., was only allowed to leave the former Soviet Union in 1991.

In science, his name is primarily associated with the Hellmann–Feynman theorem, as well as with one of the first-ever textbooks on quantum chemistry (‘Kvantovaya Khimiya’, 1937; translated into German as ‘Einfuehrung in die Quantenchemie’, Vienna, 1937). He pioneered several approaches now commonplace in quantum chemistry, notably the use of pseudopotentials.

Notes

References
 
 Translation of 
 Siegen university site
 Complete list of publications of Hans Hellmann (Freie Universität Berlin)

1903 births
1938 deaths
20th-century German chemists
People from Wilhelmshaven
People from the Province of Hanover
20th-century German physicists
University of Stuttgart alumni
University of Kiel alumni
Academic staff of the University of Hanover
Great Purge victims from Germany
Refugees from Nazi Germany in the Soviet Union
German theoretical physicists
Executed people from Lower Saxony
Stüve diagram. A Stüve diagram is one type of thermodynamic diagram commonly used in weather analysis and forecasting.

This diagram has a simplicity in that it uses straight lines for the three primary variables: pressure, temperature and potential temperature. The isotherms are straight and vertical (acting as the x-axis) while isobars are straight and horizontal (acting as the y-axis). Dry adiabats are straight and solid green but are tilted while moist adiabats do not have the same slope throughout and are dashed and cyan. Wind barbs, symbols used to show wind speed and direction, are often plotted at the side of the diagram to indicate the winds at different heights.

However, using this configuration sacrifices the equal-area property of the original Clausius–Clapeyron relation requirements between the temperature of the environment and the temperature of a parcel of air lifted/lowered. Although it permits analysis of the cloud cover and the stability of the airmass, it thus does not permit calculation of the Convective Available Potential Energy (CAPE). This is why the three other thermodynamic diagrams (emagrams, tephigrams, and skew-T log-P diagrams) are most often preferred, the latter in the USA nowadays.

See also
Thermodynamic diagrams
Skew-T log-P diagram
Emagram
Tephigram

References

 
 

Atmospheric thermodynamics
Electroluminescent display. Electroluminescent displays (ELDs) are a type of flat panel display created by sandwiching a layer of electroluminescent material such as gallium arsenide between two layers of conductors. When current flows, the layer of material emits radiation in the form of visible light. Electroluminescence (EL) is an optical and electrical phenomenon where a material emits light in response to an electric current passed through it, or to a strong electric field. The term "electroluminescent display" describes displays that use neither LED nor OLED devices, that instead use traditional electroluminescent materials. Beneq is the only manufacturer of TFEL (Thin Film Electroluminescent Display) and TAESL displays, which are branded as LUMINEQ Displays. The structure of a TFEL is similar to that of a passive matrix LCD or OLED display, and TAESL displays are essentially transparent TEFL displays with transparent electrodes. TAESL displays can have a transparency of 80%. Both TEFL and TAESL displays use chip-on-glass technology, which mounts the display driver IC directly on one of the edges of the display. TAESL displays can be embedded onto glass sheets. Unlike LCDs, TFELs are much more rugged and can operate at temperatures from −60 to 105°C and unlike OLEDs, TFELs can operate for 100,000 hours without considerable burn-in, retaining about 85% of their initial brightness. The electroluminescent material is deposited using atomic layer deposition, which is a process that deposits one 1-atom thick layer at a time.

Mechanism
EL works by exciting atoms by passing an electric current through them, causing them to emit photons. By varying the material being excited, the colour of the light emitted can be changed. The actual ELD is constructed using flat, opaque electrode strips running parallel to each other, covered by a layer of electroluminescent material, followed by another layer of electrodes, running perpendicular to the bottom layer. This top layer must be transparent in order to let light escape. At each intersection, the material lights, creating a pixel.

Uses 
Electroluminescent (EL) displays have been a niche format and are rarely used nowadays. Some uses have included the Apollo Guidance Computer 7-segment numerical displays, to indicate speed and altitude at the front of the Concorde, and as floor indicators on Otis Elevators from around 1989 to 2007, mostly only available to high-rise buildings and modernizations.  EL displays have a wider operating temperature range than LED displays.

Abbreviations
 AMEL: Active matrix electroluminescence
 TFEL: Thin film electroluminescence
 TDEL: Thick dielectric electroluminescence

See also
Electroluminescence
History of display technology
Thick-film dielectric electroluminescent technology

References

Electrical phenomena
Luminescence
Lighting
Display technology
PKP class Ok1. Ok1 is the Polish designation of a Prussian steam locomotive, the Prussian P 8, used on Polish State Railways. Production of the P 8 lasted from 1908 until 1928 and this locomotive was used on practically all European railway lines.

After the end of World War I, 192 Class P 8 engines were handed over as a reparation to Poland, including two machines for Free City of Danzig, where they were re-designated as Class Ok1 locomotives (numbers: Ok1-1 to Ok1-190 and Ok1-1Dz and 2Dz for Danzig machines). Since the class was considered successful, further 65 locomotives were built in Germany at Polish order in 1922-1923 (designated Ok1-201 to 265).

During World War II all the locomotives were captured by the Germans or Soviets and most were pressed into the German Railways. After the war, along with new war reparations, Poland received 429 locomotives P 8 (numbers Ok1-1 to 429), what made it by far the most numerous passenger locomotive in the country. They were used until the late 1970s - last locomotive was withdrawn from line service in 1981. A few engines were preserved, including Ok1-359 (see the photograph), which is stabled at the Wolsztyn museum.

See also
PKP classification system

References

External links

Railway locomotives introduced in 1908
4-6-0 locomotives
Ok01
Berliner locomotives
Passenger locomotives
Standard gauge locomotives of Poland

pl:Ok1
ISBT. ISBT can stand for:

 International Society of Blood Transfusion
 Inter State Bus Terminals, stations for public buses in India
 Inter-State Bus Terminus, Indore, Madhya Pradesh, India
 Inter-State Bus Terminal, Raipur, Chhattisgarh, India
 Babasaheb Bhimrao Ambedkar Bus Terminal, Odisha, India
 Maharana Pratap Inter State Bus Terminus, formerly Kashmiri Gate Inter State Bus Terminal, Delhi, India
1,1-Dichloroethylene. 1,1-Dichloroethylene, commonly called vinylidene chloride or 1,1-DCE, is an organochloride with the molecular formula .  It is a colorless liquid with a sharp odor. Like most chlorocarbons, it is poorly soluble in water but soluble in organic solvents. 1,1-DCE was the precursor to the original clingwrap, Saran, for food, but this application has been phased out.

Production
1,1-DCE is produced by dehydrochlorination of 1,1,2-trichloroethane, a relatively unwanted byproduct in the production of 1,1,1-trichloroethane and 1,2-dichloroethane.  The conversion is a base-catalyzed reaction which uses either NaOH or Ca(OH) with temperature ca. 100 °C. 
ClCHCHCl  +  NaOH   →   ClC=CH  +  NaCl  +  HO
The gas phase reaction, without the base, would be more desirable but is less selective.

Applications
1,1-DCE is mainly used as a comonomer in the polymerization of vinyl chloride, acrylonitrile, and acrylates.  It is also used in semiconductor device fabrication for growing high purity silicon dioxide (SiO) films.

Polyvinylidene chloride

As with many other alkenes, 1,1-DCE can be polymerised to form polyvinylidene chloride. A very widely used product, cling wrap, or Saran was made from this polymer. During the 1990s research suggested that, in common with many chlorinated carbon compounds, Saran posed a possible danger to health by leaching, especially on exposure to food in microwave ovens. Accordingly, Saran changed their formulation in 2004 to a form of polyethylene.

Safety
The health effects from exposure to vinylidene chloride are primarily on the central nervous system, including symptoms of sedation, inebriation, convulsions, spasms, and unconsciousness at high concentrations.

International Agency for Research on Cancer has put vinylidene chloride in Class 2B, meaning possibly carcinogenic to humans. National Institute for Occupational Safety and Health considers vinylidene chloride a potential occupational carcinogen.

See also
 1,2-Dichloroethene
 Dichloroethane

References

External links
Agency for Toxic Substances and Disease Registry: 1,1-Dichloroethene

Chloroalkenes
Halogenated solvents
Vinylidene compounds
1,1,2-Trichloroethane. 1,1,2-Trichloroethane, vinyl trichloride or 1,1,2-TCA, is an organochloride solvent with the molecular formula  and the structural formula . It is a colourless, sweet-smelling liquid that does not dissolve in water, but is soluble in most organic solvents. It is an isomer of 1,1,1-trichloroethane, and a byproduct of its manufacture.

It is used as a solvent and as an intermediate in the synthesis of 1,1-dichloroethylene.

Toxicity 
1,1,2-Trichloroethane may be harmful by inhalation, ingestion, and skin contact. It is a respiratory and eye irritant. 1,1,2-TCA is a central nervous system depressant and inhalation of vapors may cause dizziness, drowsiness, headache, nausea, shortness of breath, and unconsciousness.   

The Occupational Safety and Health Administration and National Institute for Occupational Safety and Health have set occupational exposure limits to 1,1,2-Trichloroethane at 10 ppm over an eight-hour time-weighted average.

References

Chloroalkanes
Halogenated solvents
GABAA receptor positive allosteric modulators
Sweet-smelling chemicals
Jon Michael Smith. Jon Michael Smith (born September 6, 1938) is an American  scientist/engineer, retired NASA officer, and author, who developed the numerical integration technique known as T-integration.

Biography 
Born in 1938, Smith holds a Bachelor of Science degree in Physics from the Jesuit Seattle University. He attended the Harvard Business School's six-week Advanced Management Program, and a past member of the MIT Sloan School of Management Complex Organizations Program.

Smith worked for NASA on their Space Shuttle program. He was the first marketing manager for the Space Shuttle. His contributions included the preparation of the pricing and use policy for the Shuttle and the first launch agreements with commercial users. Later he managed the Advanced Communication Technology Satellite experiments program and the commercialization of the NASA polar communications network. Mike retired from the NASA Johnson Space Center in Houston, Texas in January 2007.

When at NASA, Smith managed the special projects office in the Space Shuttle Program Strategic Planning office. His work dealt with NASA's response to the recommendations made by the Columbia Accident Investigation Board and with NASA's terminating the Space Shuttle Program. Prior to this assignment, he served as the Commercialization Manager for the Space Operations Management Office at JSC and served as the program manager for the Advanced Communications Technology Satellite Program.

Currently Smith is the proprietor of Jon M. Smith and Associates (JMSA), a Galveston Texas-based consulting firm whose expertise includes space commercialization initiatives & launch vehicle flight guidance and control systems. Also, JMSA is involved with commercialized telescopes and space based energy initiatives.  His clients include NASA and Wyle Labs.

Selected publications 
 Mathematical Modeling and Digital Simulation for Engineers and Scientists, 
 Scientific Analysis on the Pocket Calculator, 
 Financial Analysis & Business Decisions on the Pocket Calculator 
 Quantitative Methods in Business, McGraw Hill.

References

21st-century American engineers
American science writers
NASA people
1938 births
Living people
MIT Sloan School of Management faculty
1 Combat Engineer Regiment. 1 Combat Engineer Regiment (1 CER, ) is a Regular Force regiment of the Royal Canadian Engineers (RCE) commanded by a lieutenant-colonel.  Its headquarters is in the Patton Building at CFB Edmonton (Steele Barracks), Alberta, and it is assigned to 1 Canadian Mechanized Brigade Group.

History 
1 CER was continually involved with rotations to Afghanistan as part of the ongoing War on Terror. Due to the regiment's special armoured engineer capability, every Canadian rotation since 2006 had a minimum of an armoured troop from 1 CER attached. 

1 CER had six soldiers killed in Afghanistan.

Organization

Armoured engineers
1 CER is different from other CERs as it holds the Canadian Army's armoured engineer capability. Formerly this was provided by the Badger Armoured Engineer Vehicle (AEV) Since 2018 the Badger AEV has been replaced by a Leopard 2–based AEV that is known in Canadian service as the AEV2 (still commonly called the Badger, or Badger 2).

Order of precedence

References

Citations

Notes

External links
 

Engineer regiments of Canada
Military units and formations established in 1977
1977 establishments in Canada
HeaderDoc. HeaderDoc is a documentation generator developed and maintained by Apple Inc.  Using specially commented source code files as input, HeaderDoc generates documentation for the code in HTML or XML format.  Syntax for HeaderDoc comment tags is largely similar to, and as of HeaderDoc version 8, supportive of Javadoc tags.  HeaderDoc 8.7 and later also provides partial support for many Doxygen tags (@ form only, and must conform to HeaderDoc tag ordering rules). Apple's HeaderDoc project is free, open source software distributed under the Apple Public Source License.

Supported plain text languages 
AppleScript
Bash
Bourne Shell
C Shell
C
C++
Korn Shell
Java
JavaScript
Mach MIG definitions 
Objective-C
Pascal
Perl
PHP
Python
Ruby
Tcl

The HeaderDoc tool set consists of the main utility, headerdoc2html, and gatherheaderdoc.  The headerdoc2html tool generates a directory of either HTML (or optionally XML) files from the commented source files specified.  Afterwards, the gatherheaderdoc utility may be executed to create a table of contents file for the documentation.  Finally, the resolveLinks utility may be used to resolve cross-references between multiple documentation collections.

Apple's Xcode development environment contains features designed to assist the process of creating documentation using the HeaderDoc syntax and tools.

Additional features 

HeaderDoc has the following core features:

 C preprocessing, allowing user-selected #define macros to alter the content, and allowing the user to pass command-line flags to ignore portions of the input.
 Syntax coloring with user-defined styles.
 Template-driven landing pages for indices.
 Cross-platform (written mostly in Perl).

The HeaderDoc suite also includes several tools that may be used independently:

 MPGL—a set of tools designed to simplify creation of UNIX manual pages using a lightweight XML syntax consisting of a subset of XHTML plus section tags, parameter tags, etc.  HeaderDoc also provides a bridging tool that helps generate manual pages from header comments for functions via HeaderDoc's XML output mode.
 resolveLinks—a tool that allows for rapid web site relinking when content moves to a different address through the use of embedded anchors and link requests.
 filtermacros.pl—a tool that can be used to filter out sections of headers based on C preprocessor macros.  This is currently available only by downloading the source tarball.  As of HeaderDoc 8.9, this functionality is built into the headerdoc2html tool itself.

See also 

 Comparison of documentation generators
 Standard interface documentation

External links
Legacy Documentation: HeaderDoc User Guide
http://opensource.apple.com Latest version] (currently 8.9.28)
HeaderDoc mailing list (commonly used for getting help, patches, etc.)

Free documentation generators