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Emissions Abatement Technologies
Emission may refer to: Chemical products * Emission of Air pollution, air pollutants, notably: **Flue gas, gas exiting to the atmosphere via a flue ** Exhaust gas, flue gas generated by fuel combustion ** Emission of greenhouse gases, which absorb and emit radiant energy within the thermal infrared range * Emission standards, limits on pollutants that can be released into the environment * Emissions trading, a market-based approach to pollution control Electromagnetic radiation * Emission spectrum, the spectrum of frequencies of electromagnetic radiation generated by molecular electrons making transitions to lower energy states * Thermal emission, electromagnetic radiation generated by the thermal motion of particles in matter * List of light sources, including both natural and artificial processes that emit light * Emission (radiocommunications), a radio signal (usually modulated) emitted from a radio transmitter * Emission coefficient, a coefficient in the power output per unit ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Air Pollution
Air pollution is the presence of substances in the Atmosphere of Earth, air that are harmful to humans, other living beings or the environment. Pollutants can be Gas, gases like Ground-level ozone, ozone or nitrogen oxides or small particles like soot and dust. It affects both outdoor air and indoor air. Natural sources of air pollution include Wildfire, wildfires, Dust storm, dust storms, and Volcanic eruption, volcanic eruptions. Indoor air pollution is often Energy poverty and cooking, caused by the use of biomass (e.g. wood) for cooking and heating. Outdoor air pollution comes from some industrial processes, the burning of Fossil fuel, fossil fuels for electricity and transport, waste management and agriculture. Many of the contributors of local air pollution, especially the burning of fossil fuels, also cause greenhouse gas emissions that cause climate change, global warming. Air pollution causes around 7 or 8 million deaths each year. It is a significant risk factor for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emission Nebula
An emission nebula is a nebula formed of ionized gases that emit light of various wavelengths. The most common source of ionization is high-energy ultraviolet photons emitted from a nearby hot star. Among the several different types of emission nebulae are H II regions, in which star formation is taking place and young, massive stars are the source of the ionizing photons; and planetary nebulae, in which a dying star has thrown off its outer layers, with the exposed hot core then ionizing them.Nebulae< ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emissions Control (other)
Emissions control may refer to: * EMCON, military state of minimal radio emissions * Technology involved in vehicle emissions control * Regulation of air pollution Air pollution is the presence of substances in the Atmosphere of Earth, air that are harmful to humans, other living beings or the environment. Pollutants can be Gas, gases like Ground-level ozone, ozone or nitrogen oxides or small particles li ... via emission standards {{disambiguation ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Exhalation
Exhalation (or expiration) is the flow of the breathing, breath out of an organism. In animals, it is the movement of air from the lungs out of the airways, to the external environment during breathing. This happens due to elastic properties of the lungs, as well as the internal intercostal muscles which lower the rib cage and decrease thoracic volume. As the thoracic diaphragm relaxes during exhalation it causes the tissue it has depressed to rise superiorly and put pressure on the lungs to expel the air. During Hyperpnea, forced exhalation, as when blowing out a candle, expiratory muscles including the abdominal muscles and internal intercostal muscles generate abdominal and thoracic pressure, which forces air out of the lungs. Exhaled air is 4% carbon dioxide, a waste product of cellular respiration during the production of energy, which is stored as Adenosine triphosphate, ATP. Exhalation has a complementary relationship to inhalation which together make up the respirator ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Noise
Noise is sound, chiefly unwanted, unintentional, or harmful sound considered unpleasant, loud, or disruptive to mental or hearing faculties. From a physics standpoint, there is no distinction between noise and desired sound, as both are vibrations through a medium, such as air or water. The difference arises when the brain receives and perceives a sound. Acoustic noise is any sound in the acoustic domain, either deliberate (e.g., music or speech) or unintended. In contrast, noise in electronics may not be audible to the human ear and may require instruments for detection. In audio engineering, noise can refer to the unwanted residual electronic noise signal that gives rise to acoustic noise heard as a hiss. This signal noise is commonly measured using A-weighting or ITU-R 468 weighting. In experimental sciences, noise can refer to any random fluctuations of data that hinders perception of a signal. Measurement Sound is measured based on the amplitude and frequency of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Nocturnal Emission
A wet dream, sex dream, or sleep orgasm, is a spontaneous occurrence of sexual arousal during sleep that includes ejaculation (nocturnal emission) and orgasm for a male, and vaginal lubrication and/or orgasm for a female. Context Nocturnal emissions can happen after stressful dreams in REM sleep which activate the sympathetic nervous system, hence leading to ejaculation. They can also happen after sex dreams. Nocturnal emissions can start as early as age ten, and are most common during adolescence and early young adult years, but they may happen any time after puberty. Men can wake up during a wet dream, or sleep through it, but for women, some researchers have added the requirement that they should awaken during the orgasm, and perceive that the orgasm happened before it counts as a ''wet dream''. Vaginal lubrication alone does not mean that the woman has had an orgasm. Composition Due to the difficulty in collecting ejaculate produced during nocturnal emissions, relati ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Ejaculation
Ejaculation is the discharge of semen (the ''ejaculate''; normally containing sperm) from the penis through the urethra. It is the final stage and natural objective of male sexual stimulation, and an essential component of natural conception. After forming an erection, many men emit Pre-ejaculate, pre-ejaculatory fluid during stimulation prior to ejaculating. Ejaculation involves involuntary Muscle contraction, contractions of the pelvic floor and is normally linked with orgasm. It is a normal part of male Puberty, human sexual development. Ejaculation can occur spontaneously during sleep (a nocturnal emission or "wet dream") or in rare cases because of prostate, prostatic disease. ''Anejaculation'' is the condition of being unable to ejaculate. ''Painful ejaculation, Dysejaculation'' is an ejaculation that is painful or uncomfortable. Retrograde ejaculation is the backward flow of semen from the urethra into the urinary bladder, bladder. Premature ejaculation happens shortly ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Thermionic Emission
Thermionic emission is the liberation of charged particles from a hot electrode whose thermal energy gives some particles enough kinetic energy to escape the material's surface. The particles, sometimes called ''thermions'' in early literature, are now known to be ions or electrons. Thermal electron emission specifically refers to emission of electrons and occurs when thermal energy overcomes the material's work function. After emission, an opposite charge of equal magnitude to the emitted charge is initially left behind in the emitting region. But if the emitter is connected to a battery, that remaining charge is neutralized by charge supplied by the battery as particles are emitted, so the emitter will have the same charge it had before emission. This facilitates additional emission to sustain an electric current. Thomas Edison in 1880 while inventing his light bulb noticed this current, so subsequent scientists referred to the current as the Edison effect, though it wasn't un ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emission Theory (vision)
Emission theory or extramission theory (variants: extromission) or extromissionism is the proposal that visual perception is accomplished by eye beams emitted by the eyes. This theory has been replaced by '' intromission theory'' (or ''intromissionism''), which is that visual perception comes from something representative of the object (later established to be rays of light reflected from it) entering the eyes. Modern physics has confirmed that light is physically transmitted by photons from a light source, such as the sun, to visible objects, and finishing with the detector, such as a human eye or camera. History In the fifth century BC, Empedocles postulated that everything was composed of four elements; fire, air, earth, and water. He believed that Aphrodite made the human eye out of the four elements and that she lit the fire in the eye which shone out from the eye, making sight possible. If this were true, then one could see during the night just as well as during the da ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emission Theory (relativity)
Emission theory, also called emitter theory or ballistic theory of light, was a competing theory for the special theory of relativity, explaining the results of the Michelson–Morley experiment of 1887. Emission theories obey the principle of relativity by having no preferred frame for light transmission, but say that light is emitted at speed of light, speed "c" relative to its source instead of applying the invariance postulate. Thus, emitter theory combines electrodynamics and mechanics with a simple Newtonian theory. Although there are still proponents of this theory outside the scientific mainstream, this theory is considered to be conclusively discredited by most scientists. History The name most often associated with emission theory is Isaac Newton. In his ''corpuscular theory'' Newton visualized light "corpuscles" being thrown off from hot bodies at a nominal speed of ''c'' with respect to the emitting object, and obeying the usual laws of Newtonian mechanics, and we then ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Emission Line
A spectral line is a weaker or stronger region in an otherwise uniform and continuous spectrum. It may result from emission or absorption of light in a narrow frequency range, compared with the nearby frequencies. Spectral lines are often used to identify atoms and molecules. These "fingerprints" can be compared to the previously collected ones of atoms and molecules, and are thus used to identify the atomic and molecular components of stars and planets, which would otherwise be impossible. Types of line spectra Spectral lines are the result of interaction between a quantum system (usually atoms, but sometimes molecules or atomic nuclei) and a single photon. When a photon has about the right amount of energy (which is connected to its frequency) to allow a change in the energy state of the system (in the case of an atom this is usually an electron changing orbitals), the photon is absorbed. Then the energy will be spontaneously re-emitted, either as one photon at the same f ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
