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The E Layer (Kennelly-Heaviside Layer) is a region of ionised gas in the ionosphere, which reflects practically all incident medium frequency radiation, absorbing very little.
 Research E Layer
An earth colour is a pigment derived from the earth, as opposed to chemically manufactured pigments. Earth colours include ochre, sienna, umber, red oxide and malachite with further colours developed by calcining the materials to form for example burnt sienna. Earth colours are very stable and permanent.
Research Earth Colour
The Earth Metals are the metals which in combination with oxygen form alkaline earths. They are calcium, strontium and barium and are never found in an uncombined condition, but oxidise rapidly into lime, strontia and baryta, the alkaline earths.
Research Earth Metal
East India gum is a gum resin similar to fossiklised damar, used in flat lacquers.
Research East India Gum
Ebonite is a hard product obtained by fully vulcanising rubber with more than 20 percent of its weight of sulphur. Ebonite is very resistant to corrosion and as an excellent insulator was employed in the electrical industry.
Research Ebonite
Ebony is the heart-wood of various species of Diospyros, trees of the order Ebenaceae. It is a heavy, deep black wood used in piano keys and inlaying.
Research Ebony
Echo Sounding is measurement of the depth of the ocean by directing a sonic or ultrasonic pressure wave vertically downward and determining the time taken before the echo is received.
Research Echo Sounding
Ecology is the study of the relationship between plants and the places in which they grow. The term is becoming used to describe the opposition to man-made pollution and destruction of nature, hence an ecologist today is thought of more as an environmental campaigner than a botanist.
Research Ecology
EDAAS is an expert system that uses its knowledge of both the Toxic Substances Control Act (USA) and criteria for classifying information as confidential to help information specialists decide which information about the manufacturing and distribution of toxic chemicals must be released to the public and which information may be withheld for proprietary purposes. EDAAS was developed for the Environmental Protection Agency in the USA using FORTRAN.
Research EDAAS
Eddy currents (Foucault currents) are electric currents induced in a conductor by a varying magnetic field, for instance, in the core of an inductor or transformer.
Research Eddy Current
EditPlus (previously known as Edit++) is an Internet-ready, 32-bit text editor for the Windows operating system. While it can serve as a good replacement for Notepad, it also offers many powerful features for Web page authors and programmers. Features include a seamless browser window, customisable syntax highlighting, an HTML toolbar, user-definable tools and help files, powerful undo/redo functions, drag-and-drop editing, search and replace functions, a spelling checker, keystroke recording, and customisable keyboard shortcuts.
EditPlus also includes syntax highlighting for HTML, ASP, JavaScript, VBScript, Perl, Java, and C/C++ ; and URL and email address highlighting and activating.
Research EditPlus
The effective resistance offered by conductors to radio frequencies is considerably more than the resistance measured with direct currents. This is the result of skin effect, which causes the current to be concentrated in certain parts of the conductor and leaves the remainder of the conductor to do little or nothing toward carrying the current. As a result of this effect it is necessary to generalize the concept of conductor resistance when dealing with radio frequencies by considering the resistance to be that quantity which when multiplied by the square of the current will give the energy dissipated in the conductor. A simple example of skin effect is furnished by an isolated round wire. When a current is flowing through such a conductor, the magnetic flux that results is in the form of concentric circles. It is to be noted that some of this flux exists within the conductor and therefore links with, i.e., encircles, current near the centre of the conductor while not linking with current flowing near the surface. The result is that the inductance of the central part of the conductor is greater than the inductance of the part of the conductor near the surface. At radio frequencies the reactance of this extra inductance is sufficiently great to affect seriously the flow of current. Most of the current then flows along the surface of the conductor where the impedance is low, rather than near the centre where the impedance is high. The centre part of the conductor therefore does not carry its share of the current and the effective resistance is increased.
Skin effect occurs whenever some parts of a conductor have more flux linkages than other parts. The result of skin effect is to cause a redistribution of current over the conductor cross section of such a character that most of the current flows where it is encircled by the smallest number of flux lines. This is because those parts encircled by the fewest flux lines have the lowest inductance, and hence offer the least impedance to the current. The ratio that the effective alternating-current resistance bears to the direct-current resistance of a conductor increases with frequency and with the conductivity of the conductor material. This is because the higher frequency Increases the reactance produced by the extra flux linkages, whereas a higher conductivity causes slight differences of inductance for different parts of the conductor to have more effect on the current distribution. The non-uniformity of current distribution that results from skin effect can be reduced by employing a conductor consisting of a large number of small insulated wires connected in parallel at the terminals and thoroughly interwoven. If the interweaving is complete each conductor will on the average link with the same number of flux lines as every other conductor. This will give all the individual strands substantially the same inductance, and will therefore cause the current to distribute uniformly between the strands.
Research Effective Resistance of Conductors at Radio Frequencies
Effervescence is the rapid escape of gas from a liquid, usually due to chemical action.
Research Effervescence
In chemistry, efflorescence is the spontaneous loss of water by a substance when exposed to air.
Research Efflorescence
The Enhanced Graphics Adapter or EGA was a video card for Personal Computers produced by IBM in response to the Hercules Graphics Card, and released in 1985. The EGA could hold 256K of video RAM and display 16 colour graphics at a resolution of 640 x 350 pixels.
Research EGA
An egg is a body specially developed in the females of animals which when impregnated by a male sperm develops into the young of the animal.
Research Egg
Egg glair is a substance consisting of fresh egg white mixed with lukewarm water, and used in gilding to prevent gold leaf from sticking to varnished or enamelled work.
Research Egg Glair
Egyptian blue was the first pigment prepared by artificial means. It is a crystalline silicate of copper that produces a fine rich blue colour that was much used in fresco work.
Research Egyptian Blue
EIDE is an improved version of IDE which enables hard disk drives with a capacity in excess of 512 mB to be accessed.
Research EIDE
An eidograph is an instrument for copying drawings, designs and the like reduced or enlarged , within limits, to any desired proportion. Some what on the lines of the pantograph, the eidograph comprises a slotted beam adapted to slide in a socket, having the axis in the center line of the slot. Underneath each end of the beam is a wheel; the wheels are of the same diameter and geared together by a chain. Sliding in a guide in each wheel is an arm, one of which carries a tracer and the other a pencil, or the equivalent, for copying. The gearing together of the two wheels ensures that the arms will remain parallel for all possitions of the instrument. The size of the copy is determined by the position of the beam in the socket.
Research Eidograph
Electric current is the movement of electric charge. In a conductor the current consists of a drift of electrons towards the positive pole of the applied electric field. In an electrolyte or in a gas it consists of the migration of positive ions towards the negative electrode and of negative ions and/or electrons towards the positive electrode.
Research Electric current
An electrode is a conductor by which an electric current enters or leaves an electrolyte or an electron tube. The positive electrode is called the anode and the negative
electrode is called the cathode.
Research Electrode
In chemistry, electrolysis is the decomposition of a chemical compound by an electrical current.
Research Electrolysis
In chemistry, electrolyte is a substance which will conduct an electrical current when in solution or melted
Research Electrolyte
In chemistry, an electron is an atomic particle carrying a unit charge of negative electricity, having a mass of 1/1837 of that of a proton.
Research Electron
In chemistry, electrophoresis is the migration of colloidal particles dispersed in a fluid, under the influence of an electric field.
Research Electrophoresis
Electrostatic refers to the phenomena produced solely by electric charges or fields, and not combined with magnetic effects.
Research Electrostatic
Electrostriction is small changes in the dimensions of a dielectric when placed in an electric field.
Research Electrostriction
In chemistry, electrovalence is the valence as determined by the electrons lost or gained by the elements reacting to form a compound.
Research Electrovalence
Electrum is a naturally occurring alloy of gold and silver. The gold content varies but is usually around 65 - 80 percent. Other metals, such as copper, bismuth or palladium are also sometimes present. In Ancient Greece the term electrum was given to an alloy of gold and silver containing 80 percent gold.
Research Electrum
An element is a substance that cannot be split chemically into simpler substances.
Research Element
Elm is a command-line based UNIX email system.
Research Elm
Elutriation is the process of separating the finer particles of an earthy substance from the coarser and heavier by washing with water.
Research Elutriation
EMACS is a programmable computer text editor with an entire LISP system inside it. It was originally written by Richard Stallman in TECO under ITS at the MIT AI lab; AI Memo 554 described it as 'an advanced, self-documenting, customisable, extensible real-time display editor'. It has since been reimplemented any number of times, by various hackers, and versions exist which run under most major operating systems. Perhaps the most widely used version, also written by Stallman and now called 'GNU EMACS' or GNUMACS, runs principally under UNIX. It includes facilities to run compilation sub-processes and send and receive mail. Other variants include GOSMACS, CCA EMACS, UniPress EMACS, Montgomery EMACS, jove, epsilon, and MicroEMACS.
Research EMACS
An email client is a computer program that interacts directly with the user, allowing mail to be sent, read, filed, printed and otherwise manipulated.
Research Email Client
Embalming is the preparation of dead bodies so that they will not decay. The ancient Egyptians were especially expert and many mummies are still preserved.
Research Embalming
Emerald green is a highly toxic blue-green pigment compounded from the arsenite and acetate of copper.
Research Emerald Green
An emulsion is an extremely fine dispersion of a liquid throughout another liquid with which it is immiscible. Industrial emulsions include margarine, and paint. Within the natural world, the most common emulsion is blood.
Research Emulsion
In chemistry, an endothermic reaction is a chemical change in which heat is absorbed.
Research Endothermic reaction
In physics, the term energy refers to an object's capacity to do work. This capacity is related to the strength of the flow of electrons in the object, or, in the case of potential energy, the amount of energy stored in the object. Thus, a powerful object such as the sun expels an enormous flow of electrons as solar energy, and a single atom of hydrogen contains the pathetic energy of a single electron orbiting its nucleus.
Research Energy
Enterprise Blue is a client-server help desk application for personal computers running the Windows operating system. Enterprise Blue was designed for use by call centres and help desks, enabling them to maintain and record contact with their customers, and maintain a knowledge base of customer problems and solutions. Enterprise Blue is intended for larger organisations and operates over a network, including the internet.
Research Enterprise Blue
 More information about Enterprise Blue
The Environs Text Editor is an industrial-strength programmer's editor for the Windows operating system. It combines the ability to edit any number of files of any size and line length, including binary files, with features to speed programming, such as unlimited undo, column operations, regular expression search and replace, fully configurable keyboard, file/selection sorting and printing, and scope matching.
Research Environs Text Editor
Eosin is the potassium or sodium salt of tetrabromo-flourescein. It is a red substance which possesses brilliant flourescence in alkaline solution. It is used in acid solution as a red dye for wool and silk and is also used in red ink.
Research Eosin
Epoxide resins are used as adhesives (Araldite and other epoxy adhesives), laminates and as insulated potting materials for electronics. They are prepared by combining two complex organic chemicals into another yet more complex, are generally made useful by the further addition of a hardener.
Research Epoxide Resins
Epsom Salts is the popular name for hydrated magnesium sulphate (Epsomite), MgSO4.7H2O, the name coming from the mineral's occurrence in mineral springs in Epsom, Surrey. It is used medicinally as a cathartic, and is also used for weighting textiles.
Research Epsom Salts
In chemistry, equilibrium is a state existing in a reversible reaction when the rates of the forward and reverse reactions are equal and the concentrations of the reactants and products are equal.
Research Equilibrium
Erbium is a metal element with the symbol Er.
Research Erbium
Erg is the c.g.s. unit of work or energy, equal to the work done when a force of one dyne acts through a distance of one centimetre.
Research Erg
Ergosterol is a naturally occurring higher alcohol which upon irradiation with ultra-violet light changes into Vitamin D.
Research Ergosterol
An Erlenmeyer flask is a flask with a wide base, narrow neck and a conical form often used for swirling liquids by hand during laboratory experiments.
Research Erlenmeyer Flask
The error performing inpage operation message is an error message displayed by the Windows operating systems when it encounters a problem reading a small file (less than 256Kb) from a removable disk, such as a floppy diskette, CD-ROM or DVD. The error usually indicates a physical problem with the source diskette, CD or DVD.
Research Error Performing Inpage Operation
Erythrosine (Disodium 2-(2,4,5,7-tetraiodo-3-oxido-6-oxoxanthen-9-y1) benzoate monohydrate mixed with other colouring matters which contain arsenic, lead, mercury cadmium and other heavy metals) is a red powder used in the food industry as a red dye.
Research Erythrosine
In horology, an escapement is a device intervening between, and acted upon by both, the power and the time-measurer in a clock or watch, to convert a continuous rotary into an oscillating isochronous movement. The power through the escapement imparts to the pendulum or balance-wheel an impulse sufficient to overcome the friction of the latter and the resistance of the atmosphere, and thus keeps up the vibrations. the time-measurer (pendulum or balance-wheel) acts through the escapement to cause the motion of the train to be intermittent. Clocks and watches are generally named according to the form of their escapement: Chronometer, crown-wheel, Cylinder, Dead-beat, detached, Duplex, Horizontal and Lever escapement, &c.
Research Escapement
ESSA were a series of American satellites, the first launched in 1966 followed by two more the same year, to provide information to be used by the US Weather Bureau to improve daily weather forecasts. The first ESSA satellite was a drum-shaped device weighing 138 kg, 107 cm in diameter and 56 cm tall. In orbit it revolved in the manner of a wheel, and was equipped with two cameras on its rim and could observe the weather occuring all over the world, photographing and transmitting the weather conditions back to command stations at Fairbanks, Alaska and Wallops, Virginia.
Research ESSA
The essential oils (ethereal oils, volatile oils) are a group of naturally occurring sometimes pleasant-smelling liquids of vegetable origin. They are extracted either by pressing or distillation and are of several types; terpenes or similar hydro-carbons, aromatic aldehydes, and esters. The terpenes are largely used for solvents, the others for perfumes and flavourings.
Research Essential Oil
Ester is an organic compound formed by the reaction between alcohol and acid with the elimination of water.
Research Ester
Ethane is a paraffin hydrocarbon. It is a colourless, odourless gas used as a fuel in the form of natural gas.
Research Ethane
Ethanoic acid is an organic fatty acid.
Research Ethanoic acid
Ethanol is another name for ethyl alcohol.
Research Ethanol
Ethene is an alkene hydrocarbon gas.
Research Ethene
Ethernet was originally the trade name for a LAN developed by Xerox Corporation and later supported by Digital Equipment Corporation, Intel Corporation and Hewlett-Packard. It is now standardised as IEEE specification 802. 3 .
Research Ethernet
Ethnology is the science dealing with the inter-relatedness of the human family in terms of the physical appearance, customs, culture, art, economics etc.
Research Ethnology
Ethyl is a compound radicle, a colourless gas, with a slightly ethereal odour, a compound of carbon and hydrogen. It was first obtained in the free state by Edward Frankland in 1849.
Research Ethyl
Ethyl Acetate (acetic ether) is a colourless liquid with a characteristic fruity odour prepared by the esterification of ethyl alcohol with acetic acid. It is used as a solvent and as a flavouring agent.
Research Ethyl Acetate
Ethyl acrylate is a colourless, flammable liquid with a penetrating acrid odour. It is used primarily as an intermediate in the production of emulsion-based polymers, including those used in textile treatment, surface coatings, paper treatment, polishes, adhesives, leather treatment, and other emulsion-based polymers. Ethyl acrylate is also used in the production of other polymers, including solvent-based surface coatings. Ethyl acrylate is soluble in ethanol, ether, and chloroform and is slightly soluble in water. It is incompatible or reactive with oxidizers, peroxides, polymerises, strong alkalis, moisture, and chlorosulfonic acid. It polymerises readily unless an inhibitor such as hydroquinone is added. When heated to decomposition, ethyl acrylate emits smoke and acrid fumes. Ethyl acrylate is also known as acrylic acid ethyl ester, ethyl propenoate, ethoxycarbonylethylene, ethyl-2-propenoate, and NCI-C50384.
Research Ethyl Acrylate
Ethyl alcohol (ethanol) is the nbest known of the alcohols - it is the alcohol found in beverages and is obtained by the alcoholic fermentation of carbohydrates. It is a colourless, spicy-smelling liquid with a burning taste. Ethyl alcohol is combustible and easily ignites. Ethyl alcohol is used in beverages, as a solvent and in industrial synthesis (synthetic chemistry), and widely in perfumes.
Research Ethyl Alcohol
Ethyl fluid is a mixture consisting principally of tetra-ethyl lead which was formerly added to petrol as an anti-knocking agent.
Research Ethyl Fluid
Ethylene is a gaseous hydrocarbon with the formulae C2H4. It contains one double bond and is the simplest example of an unsaturated compound.
Research Ethylene
Ethylene Glycol is a sweet syrupy liquid miscible with water and employed as an anti-freeze mixture in motor-car radiators and also as a solvent.
Research Ethylene Glycol
Ethylene glycol monobutyl ether is a glycol ether used in hydraulic fluids, as a coupling agent for water-based coatings, in vinyl and acrylic paints and varnishes, and as a solvent for varnishes, enamels, spray lacquers, dry cleaning compounds, textiles, and cosmetics.
Ethylene glycol monobutyl ether is a colourless liquid with a mild, rancid, ether-like odour. It is soluble in most organic solvents and mineral oil. It mixes with acetone, benzene, carbon tetrachloride, ethyl ether, n-heptane and water; it is miscible with many ketones, ethers, alcohols, aromatic paraffin, and halogenated hydrocarbons. Ethylene glycol monobutyl ether is also known as ethylene glycol mono-n-butyl ether.
Research Ethylene glycol monobutyl ether
Ethylene glycol monoethyl ether is a glycol ether used in varnish removers, lacquers, and as a solvent for printing inks, duplicating fluids, and epoxy.
Ethylene glycol monoethyl ether is a colourless liquid with a sweet, mild odour and slightly bitter taste. It is miscible in all proportions of acetone, benzene, carbon tetrachloride, ethyl ether, methanol, and water. It dissolves many oils, resins, and waxes.
Research Ethylene glycol monoethyl ether
Etymology is the science of the origin and relationship of words.
Research Etymology
An eudiometer is a chemical apparatus introduced by Joseph Priestley in 1770, consisting of a graduated glass tube with one end closed. By submerging the open end of the tube under water and introducing a known volume of gas, the change in volume that occurs in the reaction between the two gases can be measured. The eudiometer was first used in the estimation of the amount of oxygen in the air.
Research Eudiometer
Eudora is an email client program for the Windows operating system and also the Mac computer, operating on TCP/ IP networks (such as the Internet).
Research Eudora
Eugenics is the science of selective breeding to control physical and mental characteristics. It was proposed in 1904 by Francis Galton as a new division of social science that would embrace the study of 'all the influences that improve the inborn qualities of the human race, and tend to develop them to the utmost advantage.'
Research Eugenics
Eureka from Borland International is a computer program that can solve any linear or non-linear equation and is designed for the person who frequently works with variables and unknowns in the business and scientific world.
Eureka's structured environment is perfect for the professional or technical person who may not have a broad understanding of numerical analysis techniques. After you enter an equation using Eureka's text editor, select the Solve command and Eureka will determine the values of the variables in equations.
Eureka solves the problem, graphs the solution, and creates a report including assumptions, graphs, and solutions. Eureka solves inequalities and performs automatic conversions for units of measure. The product includes built-in trigonometric, logarithmic, exponential, statistical, and financial functions. Eureka contains a powerful on-screen calculator that performs all one-variable arithmetic functions quickly and simply as if you were working with a scientific hand-held calculator.
Eureka's separate windows are dedicated to certain commands, making it easy to write, edit, and solve equations interactively. The full-screen editor, which is identical to those in SideKick and Turbo Pascal, uses standard ASCII syntax and editing commands. You can import equation files from other ASCII editors.
Eureka is well equipped to handle optimisation or linear programming problems. You can solve a system of equations based on certain constraints, such as maximising profits, creating the optimal product mix or creating the most efficient work schedule. Eureka includes a number of sample problems that range from determining probabilities in a card game to calculating payments on a car loan. There are specialised accounting functions that financial analysts will find useful for money- management.
Research Eureka
Europium is a rare metal element with the symbol Eu.
Research Europium
Examine by Aquila Software is a fast and versatile text search utility that can search both text and binary files using either ordinary words or GREP-like regular expressions, the UNIX searching utility, for more sophisticated searches. Searches can be across multiple drives over networks or can be restricted to a single directory with the option of searching subdirectories if so desired. Files can be viewed either with their associated application or with the program's own fully configurable internal viewer.
Research Examine
ExamineZip by Aquila Software is a PC utility that searches for files and text within files stored in ZIP archives created with PKZIP. File searches can use DOS wild-cards while text searches can use either ordinary words or GREP-like regular expressions. Each search can be across multiple drives over networks or can be restricted to a single directory. The program can also be used as a fully functional UNZIP utility where the contents of an archive can be listed, viewed, tested or extracted to disk. Pkunzip is not required.
Research ExamineZip
In chemistry, exothermic reaction is a chemical change in which heat is liberated.
Research Exothermic reaction
In audio engineering an expander is a form of automatic level control. By attenuating the signal below the threshold, the expander reduces low-level noise or expands the dynamic range of the recorded material.
Research Expander
With few exceptions, substances expand when heated, and very large forces may be set up if there is an obstruction to the free movement of the expanding or contracting bodies. If concrete road surfaces were laid down in one continuous piece cracks would appear owing to the expansion and contraction brought about by the difference between summer and winter temperatures. To avoid this, surfaces are laid in small sections, each one being separated from the next by a small gap which is filled in with a compound of pitch. On a hot summer day this material will often be seen to have squeezed out of the joints on account of the expansion. In the older methods of laying railway tracks gaps have to be left between successive lengths of rail to allow for expansion. Even when such gaps have been left the rails may sometimes 'creep' and close up the gaps. If this happens a rise in temperature may lead to buckling of the track.
Free movement at the rail joints is allowed for by making the bolt holes of the plates joining the tracks, slotted. In modern practice, however, railway lines are welded together to form long, continuous lengths. With this method, it is only the last fifty to one hundred meters of any length which show expansion, usually of a few centimetres. This movement is taken up by planning the ends of the rails and overlapping them. The forces set up by expansion in the remainder of the rails are, so to speak, locked up in the metal. To keep these forces to a minimum, it is usual to lay the track at a time when the temperature is midway between the summer and winter averages. This technique has been made possible by the use of concrete sleepers and improved methods of fixing the rails so that the track may withstand the thermal stresses set up in it without buckling. Allowance also has to be made for the expansion of bridges and the roofs of buildings made of steel girders. Various methods are used to overcome the difficulty, a common one being to have one end only of the structure fixed while the other rests on rollers. Free movement is thus permitted in both directions. Over a very long period of years, expansion and contraction causes 'creeping' of the lead on the sloping roofs of buildings. When heated by the sun the lead expands and tends to move down the roof under its own weight. On cooling and contracting, the force of contraction is opposed by gravity and the friction of the lead against the roof. This sets up a strain in the lead gives it a slight permanent stretch. After many years the lead stretches so much it eventually forms folds and may break.
Research Expansion of Solids
An extensometer is an apparatus employed for measuring the strain produced in material when stressed.
Research Extensometer
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Abbreviations
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