Super heroes and powers. Gas. The gaseous state of matter is found between the liquid and plasma states,[1] the latter of which provides the upper temperature boundary for gases. Bounding the lower end of the temperature scale lie degenerative quantum gases[2] which are gaining increasing attention.[3] High-density atomic gases super cooled to incredibly low temperatures are classified by their statistical behavior as either a Bose gas or a Fermi gas. For a comprehensive listing of these exotic states of matter see list of states of matter.
Elemental gases[edit] The only chemical elements which are stable multi atom homonuclear molecules at standard temperature and pressure (STP), are hydrogen (H2), nitrogen (N2) and oxygen (O2); plus two halogens, fluorine (F2) and chlorine (Cl2). Etymology[edit] An alternative story[6] is that Van Helmont's word is corrupted from gahst (or geist), signifying a ghost or spirit. Physical characteristics[edit] Macroscopic[edit] Shuttle imagery of re-entry phase. Pressure[edit] Avogadro's law. Avogadro's law (sometimes referred to as Avogadro's hypothesis or Avogadro's principle) is an experimental gas law relating volume of a gas to the amount of substance of gas present. A modern statement of Avogadro's law is: Avogadro's law states that, "equal volumes of all gases, at the same temperature and pressure, have the same number of molecules".For a given mass of an ideal gas, the volume and amount (moles) of the gas are directly proportional if the temperature and pressure are constant. which can be written as: or where: V is the volume of the gas This law explains how, under the same condition of temperature and pressure, equal volumes of all gases contain the same number of molecules.
The equation shows that, as the number of moles of gas increases, the volume of the gas also increases in proportion. Mathematical definition[edit] Avogadro's law is stated mathematically as: Where: V is the volume of the gas(es). n is the amount of substance of the gas. k is a proportionality constant. Perfect gas. In physics, a perfect gas is a theoretical gas that differs from real gases in a way that makes certain calculations easier to handle. Its behavior is more simplified compared to an ideal gas (also a theoretical gas). In particular, intermolecular forces are neglected, which means that one can use the ideal gas law without restriction and neglect many complications that may arise from the Van der Waals forces.
Perfect gas nomenclature[edit] The terms perfect gas and ideal gas are sometimes used interchangeably, depending on the particular field of physics and engineering.[1] Sometimes, other distinctions are made, such as between thermally perfect gas and calorically perfect gas, or between imperfect, semi-perfect, perfect, and ideal gases. Thermally and calorically perfect gas[edit] A thermally perfect gas Even more restricted is the calorically perfect gas for which, in addition, the specific heat is assumed to be constant: and References[edit] See also[edit] Endothermic gas. Endothermic gas is a gas that inhibits or reverses oxidation on the surfaces it is in contact with. This gas is the product of incomplete combustion in a controlled environment. An example is hydrogen gas (H2), nitrogen gas (N2), and carbon monoxide (CO). The hydrogen and carbon monoxide are reducing agents, so they work together to shield surfaces from oxidation.
Forming gas. Taken (TV miniseries) The show takes place from 1944 to 2002 and follows the lives of three families: the Crawfords, who seek to cover up the Roswell crash and the existence of aliens; the Keys, who are subject to frequent experimentation by the aliens; and the Clarkes, who sheltered one of the surviving aliens from the crash. As a result of the decades-long storyline, not a single actor or character appears in every episode of the series. Reception was positive, and the series won an Emmy Award. When the show was launched, the Sci-Fi Channel used the simultaneous establishment of the organization Coalition for Freedom of Information in its promotion campaign.
Both the Sci-Fi Channel and the Coalition for Freedom of Information are clients of Washington, D.C. public relations firm PodestaMattoon, and this apparent co-mingling of clients was criticized. Taken spans five decades and four generations, and centers on three families: the Keys, the Crawfords, and the Clarkes. James Cameron. Exploration of Mars. Overview of the exploration of Mars Current status[edit] There are seven orbiters surveying the planet: Mars Odyssey, Mars Express, Mars Reconnaissance Orbiter, MAVEN, the Trace Gas Orbiter, the Hope Mars Mission, and the Tianwen-1 orbiter, which have contributed massive amounts of information about Mars.
Thus there are 10 total vehicles currently exploring Mars: 2 rovers, 1 helicopter, and 7 orbiters. Various Mars sample return missions are being planned like NASA-ESA Mars Sample Return that will pick up the samples currently being collected by the Perseverance rover.[8] The next missions expected to arrive at Mars are: Martian system[edit] Launch windows[edit] Past and current missions[edit] The Soviet probes Phobos 1 and 2 were sent to Mars in 1988 to study Mars and its two moons, with a focus on Phobos. Missions that ended prematurely after Phobos 1 and 2 (1988) include (see Probing difficulties section for more details): Overview of missions[edit] Early Soviet missions[edit] 1960s[edit] Mars. Subgiant. Subgiants A subgiant star is a star that is slightly brighter than a normal main-sequence (dwarf) star of the same spectral class, but not as bright as true giant stars. Although certain subgiants appear to be simply unusually bright metal-rich hydrogen-fusing stars (in the same way subdwarfs are unusually dim metal-poor hydrogen-fusing stars), they are generally believed to be stars that are ceasing or have already ceased fusing hydrogen in their cores.
In stars of roughly a solar mass, this causes the core to contract, which increases the star's central temperature enough to move hydrogen fusion into a shell surrounding the core. This swells the star on the way to becoming a true giant. At the start of the subgiant phase (such as a star like Procyon A and Omicron2 Cancri) the diameter and brightness have increased, but the star has yet to cool down or change color significantly. Many subgiants are rich in metals, and commonly host orbiting planets. Steam shower. History[edit] Steam showers have evolved from the steambath which is thought to have been invented during the height of the Roman Empire. Ancient Roman baths served many community and social functions within Roman society. These Roman baths were supplied by natural hot springs from beneath the ground. Features[edit] A steam shower could be a regular shower with the added steam feature that is powered by a steam generator.
Notes[edit] See also[edit] Hypoventilation. Causes[edit] It can be caused by medical conditions, such as stroke affecting the brainstem, by holding one's breath, like during hypoventilation training,[2] or by drugs, typically when taken in overdose. Hypocapnia stimulates hypoventilation. Hypoventilation may also occur in chronic mountain sickness to conserve energy.[3] Effects[edit] As a side effect of medicines or recreational drugs, hypoventilation may become potentially life-threatening. Many different CNS depressant drugs such as alcohol, benzodiazepines, barbiturates, GHB, sedatives and opiates produce respiratory depression when taken in large or excessive doses; however this is most commonly seen as a cause of death with opiates or opioids, particularly when they are combined with sedatives such as alcohol or benzodiazepines.
Treatment[edit] Respiratory stimulants such as nikethamide were traditionally used to counteract respiratory depression from CNS depressant overdose, but were of only limited effectiveness. Atmosphere of Uranus. Layer of gases surrounding the planet Uranus The Uranian atmosphere can be divided into five main layers: the troposphere, between altitudes of −300[a] and 50 km and pressures from 100 to 0.1 bar; the stratosphere, spanning altitudes between 50 and 4000 km and pressures of between 0.1 and 10−10 bar; and the hot thermosphere (and exosphere) extending from an altitude of 4,056 km to several Uranian radii from the nominal surface at 1 bar pressure. Unlike Earth's, Uranus's atmosphere has no mesosphere. Little is known about the Uranian atmosphere as to date only one spacecraft, Voyager 2, which passed by the planet in 1986, obtained some valuable compositional data. The Uranus Orbiter and Probe is scheduled to launch in 2031, arriving at Uranus in 2044.
Observation and exploration[edit] The observational history of the Uranian atmosphere is long and full of error and frustration. Composition[edit] Knowledge of the isotopic composition of Uranus's atmosphere is very limited. Structure[edit] Frontonasal duct. Technetium star. A technetium star, or more properly a Tc-rich star, is a star whose stellar spectrum contains absorption lines of the light radioactive metal technetium. The most stable isotope of technetium is 98Tc with a half-life of 4.2 million years, which is too short a time to allow the metal to be material from before the star's creation. Therefore, the detection in 1952 of technetium in stellar spectra provided unambiguous proof of nucleosynthesis in stars,[1] one of the more extreme cases being R Geminorum.[2] Stars containing technetium belong to the class of asymptotic giant branch stars (AGB) — stars that are like red giants, but with a slightly higher luminosity, and which burn hydrogen in an inner shell.
Members of this class of stars switch to helium shell burning with an interval of some 100,000 years, in "dredge-ups". Technetium stars belong to the classes M, MS, S, SC and C-N. They are most often variable stars of the long period variable types. See also[edit] References[edit] Breathing. A schematic view of the human respiratory system. In addition to removing carbon dioxide, breathing results in loss of water from the body. Exhaled air has a relative humidity of 100% because of water diffusing across the moist surface of breathing passages and alveoli. When a person exhales into very cold outdoor air, the moisture-laden atmosphere from the lungs becomes chilled to the point where the water condenses into a fog ("seeing the breath"). Mechanics[edit] In Mammals, breathing in, or inhaling, is due to the contraction and flattening of the diaphragm, a domed muscle that separates thorax and abdomen. Diaphragm, Intercostal Muscles, Scalenes, Pectoralis Minor, Serratus Anterior, Sternocleidomastoid, Levator Costarum, Upper Trapezius, Latissmus Dorsi, and Subclavis.
Eight are used for forced expiration:[4] Internal intercostal, Obliquus Internus, Obliquus Externus, Levator Ani, Triangularis Sterni, Transversalis, Pyramidalis, and Rectus Abdominus. Control of breathing[edit] Water vapor. Water vapor is a relatively common atmospheric constituent, present even in the Solar atmosphere as well as every planet in the Solar System and many astronomical objects including natural satellites, comets and even large asteroids.
Likewise the detection of extrasolar water vapor would indicate a similar distribution in other planetary systems. Water vapor is significant in that it can be indirect evidence supporting the presence of extraterrestrial liquid water in the case of some planetary mass objects. Being a component of Earth's hydrosphere and hydrologic cycle, it is particularly abundant in Earth's atmosphere where it is also a potent greenhouse gas along with other gases such as carbon dioxide and methane. Use of water vapor, as steam, has been important to humans for cooking and as a major component in energy production and transport systems since the industrial revolution. Occurrence[edit] Water vapor is a significant component of the Earth's atmosphere and a greenhouse gas.