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Ecological succession

Ecological succession, is the process by which a specific ecology has more or less orderly and predictably changed after a disturbance like a fire. In long-term studies, there is a species succession process in the way forests develop.

                                               

Ectasian

The Ectasian is the second geological period in the Mesoproterozoic. It began 1.4 billion years ago and ended at 1.2 billion years ago. The Ectasian came after the Calymmian and before the Stenian. This period shows for the first evidence of sexu ...

                                               

Egyptian calendar

The ancient civil Egyptian calendar was a calendar used by the ancient Egyptians. At first it had a year that was 365 days long. The year was made up of 12 months each having 30 days. At some point during the First Dynasty five additional days we ...

                                               

Electric chair

An electric chair is a specially built chair which is used to execute condemned criminals by electrocuting them. This means that they are being killed as a punishment for a crime that they were accused of, usually murder. An electric chair is a s ...

                                               

Electric power distribution

Electric power distribution is the delivery system of electricity to places that use it, such as homes and other buildings. It is done mainly by power lines, transformers, substations and meters. The electricity comes from the power station at hi ...

                                               

Electrical conductivity

Electrical conductivity is the measure of a materials ability to allow the transport of an electric charge. Its SI is the siemens per meter, or, more simply, Sm −1. It is the ratio of the current density to the electric field strength. It is equi ...

                                               

Electrical resistivity

Electrical resistivity is a concept in electrical engineering. It is a measure of how much a material stops the flow of electric current through it. Most metals have very low electrical resistivity. More precisely, "the resistivity of a material ...

                                               

Electrode

An electrode is an electrical conductor that carries electricity. It is used to touch a non-metal part of a circuit. The two types of electrodes are anode and cathode.

                                               

Electroencephalography

Electroencephalography is a way to record certain patterns of brain activity, on the skin of the head. Nerve cells use electricity to transmit information. It is one of the methods of diagnosis which can be used for conditions that affect the ner ...

                                               

Electrolysis of water

Electrolysis of water is the decomposition of water into oxygen and hydrogen gas. This technique can be used to produce breathable oxygen or hydrogen gas as a fuel source, referred to as hydrogen fuel. However, that method is more expensive than ...

                                               

Electrolyte

An electrolyte is a chemical that conducts electrical current. It is used in batteries to make the ions flow, producing current. Electrolytes ionize when dissolved in suitable solvents such as water. Most soluble salts, acids, and bases are elect ...

                                               

Electromagnetic Pulse

An Electromagnetic Pulse, or EMP, is a burst of electromagnetic radiation, and is caused by a huge release of energy. A "common" cause for an electromagnetic pulse is a nuclear explosion. A scientist named Enrique Fermi predicted that electromagn ...

                                               

ELISPOT

ELISPOT stands for "Enzyme-Linked Immunosorbent Spot Assay". It is a laboratory technique for detecting cells that make various substances. These substances include specific types of cytokines or antibodies. The ELISPOT method is typically used w ...

                                               

Ell

The English unit of length ell is usually 45 inches. That means 1.143 m. It came from the length of the arm from the shoulder to the wrist, although the exact length was never defined in English law. Several different national forms existed, with ...

                                               

Elongation

Elongation is an astronomical term that describes the angle between the Sun and a planet, as viewed from Earth. When an inferior planet Mercury or Venus is visible after sunset, it is near its greatest eastern elongation. When an inferior planet ...

                                               

Embryo transfer

Embryo transfer is a medical procedure. It is a step in the process of assisted reproduction, which uses science and medical treatments to help women who have difficulty getting pregnant. In embryo transfer, embryos are placed in a womans uterus. ...

                                               

Emotional intelligence

Emotional intelligence is a thought model that claims that to be successful, people must be able to know their own feelings. They must also be able to guess and influence the emotions of other people, and of groups of other people. There are seve ...

                                               

Emulsifier

An emulsifier is an additive which helps two liquids mix. For example, water and oil separate in a glass, but adding an emulsifier will help the liquids mix together. Some examples of emulsifiers are egg yolks and mustard.

                                               

Enceladus (moon)

Enceladus is a moon of Saturn. It is the sixth largest of Saturns moons, and it has a diameter of 500 km. Enceladus is within Saturns E ring and likely contributes material to it. The moon is made mostly out of water ice, so it reflects light ver ...

                                               

Enthalpy of vaporization

The Enthalpy of vaporization, also called the latent heat of vaporization is the change in the enthalpy needed to change an amount of liquid into a gas. It happens at a given pressure. The enthalpies of vaporization are usually measured at the no ...

                                               

Epipalaeolithic

The Epipaleolithic or "peripheral old stone age" is a term used for the hunter-gatherer cultures that existed after the end of the last ice age, before the Neolithic. The term is sometimes confused with Mesolithic, and the two are sometimes used ...

                                               

Epsilon Aurigae

Epsilon Aurigae, also called Maaz or Almaaz, is a yellow supergiant star forming part of the Auriga constellation. It is orbited by a binary star which is surrounded by a thick dusk cloud. The dust cloud only creates infrared light. The dust clou ...

                                               

Erriapus (moon)

Erriapus or Saturn XXVIII, is non-spherical moon of Saturn. It was found by Brett Gladman, John J. Kavelaars, et al. in 2000, and given the designation S/2000 S 10. It was named in August 2003 after Erriapo, a giant in Gaulish mythology. Later, t ...

                                               

ESTCube-1

ESTCube-1 is the first satellite from Estonia. It was made as part of the Estonian Student Satellite Program, and was launched on 7 May 2013 on a Vega rocket. The satellite is a project in which university and high-school students took part. The ...

                                               

Euanthe (moon)

Euanthe or Jupiter XXXIII is a moon of Jupiter which is not fully round. It was found by a team of astronomers from the University of Hawaii led by Scott S. Sheppard in 2001. It was given the designation S/2001 J 7. Euanthe is about 3 kilometres ...

                                               

Euporie (moon)

Euporie or Jupiter XXXIV is a moon of Jupiter. It was found by a team of astronomers from the University of Hawaii led by Scott S. Sheppard in 2001, and given the designation S/2001 J 10. Euporie is about 2 kilometres in diameter, and orbits Jupi ...

                                               

European windstorm

A European windstorm is an extratropical cyclone that affects Europe. They are normally caused by areas of low atmospheric pressure that move across the North Atlantic towards northwestern Europe. They are most common in the winter months. Low pr ...

                                               

Excitation (magnetic)

Excitation is a process to create a magnetic field from electric current. This process is used in electric machines whose rotor spins in a magnetic field. This magnetic field can come from a permanent magnet or field coils. In the case of electri ...

                                               

Exosphere

The exosphere is the highest and top layer of the Earths atmosphere. It marks the edge of space. There are very few molecules in this layer. The lightest atmospheric gases such as hydrogen and helium exist throughout the exosphere. Heavier ones l ...

                                               

Experiment

An experiment is a test of an idea or a method. It is often used by scientists and engineers. An experiment is used to see how well the idea matches the real world. Experiments have been used for many years to help people understand the world aro ...

                                               

Explosive material

Explosives are chemical compounds that cause explosions; they flare up and burst with a loud sound. Explosive material has many special characteristics: it is a chemically unstable material, it changes its form very fast and, while changing its f ...

                                               

Extragalactic astronomy

Extragalactic astronomy is astronomy about objects outside our Milky Way galaxy. It is the study of everything that is not covered in galactic astronomy: the study of objects in our galaxy. Because of improvements in technology, we can see distan ...

                                               

Extraterrestrial life

Extraterrestrial life is life that is not from the planet Earth. It is alien life. The word Terra in Latin refers to our planet - Earth. Thus, Extraterrestrial Life refers to the life forms not originating on or from the planet Earth. It is reaso ...

                                               

Extrusion

Extrusive means to the mode of igneous volcanic rock formation in which hot magma from inside the Earth flows out onto the surface as lava or explodes violently into the atmosphere to fall back as pyroclastics or tuff. This is opposed to intrusiv ...

                                               

Eye (cyclone)

The eye is an area of calm weather in the center of strong tropical cyclones. The cyclones lowest barometric pressure occurs in the eye. It is usually circular and range between 30 and 65 km in diameter, though smaller and larger eyes can occur. ...

                                               

Facies

Facies is a term in geology. It means the look of a rock. If one looks up at a cliff of rock, the appearances changes from one layer to another. This because the ecological conditions changed as the rock was laid down. So, the facies reflect the ...

                                               

False memory

Both perception and remembering are processes which involve the brain. For this reason, errors do sometimes occur. Errors in perception are commonly called illusions. Emil Kraepelin used the term "Erinnerungsverfalschung" to speak about false mem ...

                                               

Fanconi anemia

Fanconi anemia is a rare genetic disorder. It is a kind of anemia. People suffering from the disease produce a smaller amount of red and white blood cells. It is named after Guido Fanconi who first described the disease, in 1929. It should not be ...

                                               

Faraday cage

A Faraday cage or Faraday shield is an enclosure made from material that conducts electricity. It is used to block electric fields. The Faraday cage is named after the English scientist Michael Faraday, who invented it in 1836. An electrical fiel ...

                                               

Farbauti (moon)

Farbauti or Saturn XL is a moon of Saturn. It was found by Scott S. Sheppard, David C. Jewitt, and Jan Kleyna on December 12, 2004. Farbauti was found using the Mauna Kea Observatory and is the 40th moon from Saturns surface. The public did not k ...

                                               

Feldspar

Feldspar is the name of a group of rock-forming tectosilicate minerals that make up as much as 60% of the Earths crust. Feldspar forms crystals from magma in both intrusive and extrusive rocks, and they can also happen as compact minerals, as vei ...

                                               

Fenrir (moon)

Fenrir is also a mythical creature from Norse mythology Fenrir or Saturn XLI is a moon of Saturn. Its discovery was announced by Scott S. Sheppard, David C. Jewitt, Jan Kleyna, and Brian G. Marsden on May 4, 2005, from observations taken between ...

                                               

Fermi paradox

Enrico Fermis paradox wonders why, given the age and size of the universe and that there are billions of stars and planets that have existed for billions of years, we have not detected any other alien civilizations. There have been attempts to re ...

                                               

Film processing

Photographic film is able to record images. In order to make these images visible, the film needs to undergo a number of chemical processes. The result of these processes will either be negatives or slides. This is generally known as developing. ...

                                               

Fire triangle

The fire triangle is used to show the rule that a fire needs three things to burn. These things are heat, fuel, and oxygen. If one of these three is removed, the fire will be put out. In the middle of the fire triangle there is also a chemical re ...

                                               

First light (astronomy)

In astronomy, first light is the first time a telescope is used to look at the Universe. This is often not the first time the telescope has been used. Tests will have been done during daylight to make sure everything is working. Images taken duri ...

                                               

Flamsteed designation

Flamsteed designations are for stars that are similar to Bayer designations. However, they use numbers instead of Greek letters. Flamsteed designation contained 2554 stars. The numbers are usually assigned in the order of increasing right ascensi ...

                                               

Flash point

The flash point of a volatile substance is the lowest temperature at which it can become vapor, mix with air, and burn. The flash point describes liquid fuel. It helps to tell about the danger of fire from liquids." Flash point” can describe both ...

                                               

Flood control

Flood control is a term to refer to measures that protect settlements, people and property against flooding. Such measures include building dams, levees and weirs. People also move away from floodplains where flooding is frequent. Although it may ...

                                               

Fog

Fog is thick mist. It may appear on land or sea and it usually lowers visibility. When fog forms at high levels it creates a cloud called stratus. When the air chills, moisture will turn to fog. Fog is made up of tiny water droplets or, in very c ...

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