title: Thermoelectric effect

text: If the material is not in a steady state, a complete description needs to include dynamic effects such as relating to electrical capacitance, inductance and heat capacity.


title: Thermoelectric effect

text: The thermoelectric effects lie beyond the scope of equilibrium thermodynamics. They necessarily involve continuing flows of energy. At least, they involve three bodies or thermodynamic subsystems, arranged in a particular way, along with a special arrangement of the surroundings. The three bodies are the two different metals and their junction region. The junction region is an inhomogeneous body, assumed to be stable, not suffering amalgamation by diffusion of matter. The surroundings are arranged to maintain two temperature reservoirs and two electric reservoirs. For an imagined, but not actually possible, thermodynamic equilibrium, heat transfer from the hot reservoir to the cold reservoir would need to be prevented by a specifically matching voltage difference maintained by the electric reservoirs, and the electric current would need to be zero. In fact, for a steady state, there must be at least some heat transfer or some non-zero electric current. The two modes of energy transfer, as heat and by electric current, can be distinguished when there are three distinct bodies and a distinct arrangement of surroundings. But in the case of continuous variation in the media, heat transfer and thermodynamic work cannot be uniquely distinguished. This is more complicated than the often considered thermodynamic processes, in which just two respectively homogeneous subsystems are connected.


title: Thermoelectric effect

text: In 1854, Lord Kelvin found relationships between the three coefficients, implying that the Thomson, Peltier, and Seebeck effects are different manifestations of one effect (uniquely characterized by the Seebeck coefficient).


title: Thermoelectric effect

text: where formula_33 is the absolute temperature, formula_19 is the Thomson coefficient, formula_35 is the Peltier coefficient, and formula_5 is the Seebeck coefficient. This relationship is easily shown given that the Thomson effect is a continuous version of the Peltier effect.


title: Thermoelectric effect

text: This relation expresses a subtle and fundamental connection between the Peltier and Seebeck effects. It was not satisfactorily proven until the advent of the Onsager relations, and it is worth noting that this second Thomson relation is only guaranteed for a time-reversal symmetric material; if the material is placed in a magnetic field or is itself magnetically ordered (ferromagnetic, antiferromagnetic, etc.), then the second Thomson relation does not take the simple form shown here.


title: Thermoelectric effect

text: The Thomson coefficient is unique among the three main thermoelectric coefficients because it is the only one directly measurable for individual materials. The Peltier and Seebeck coefficients can only be easily determined for pairs of materials; hence, it is difficult to find values of absolute Seebeck or Peltier coefficients for an individual material.


title: Thermoelectric effect

text: If the Thomson coefficient of a material is measured over a wide temperature range, it can be integrated using the Thomson relations to determine the absolute values for the Peltier and Seebeck coefficients. This needs to be done only for one material, since the other values can be determined by measuring pairwise Seebeck coefficients in thermocouples containing the reference material and then adding back the absolute Seebeck coefficient of the reference material. For more details on absolute Seebeck coefficient determination, see Seebeck coefficient.


title: Thermoelectric effect

text: The Seebeck effect is used in thermoelectric generators, which function like heat engines, but are less bulky, have no moving parts, and are typically more expensive and less efficient. They have a use in power plants for converting waste heat into additional electrical power (a form of energy recycling) and in automobiles as automotive thermoelectric generators (ATGs) for increasing fuel efficiency. Space probes often use radioisotope thermoelectric generators with the same mechanism but using radioisotopes to generate the required heat difference. Recent uses include stove fans, lighting powered by body heat and a smartwatch powered by body heat.


title: Thermoelectric effect

text: The Peltier effect can be used to create a refrigerator that is compact and has no circulating fluid or moving parts. Such refrigerators are useful in applications where their advantages outweigh the disadvantage of their very low efficiency. The Peltier effect is also used by many thermal cyclers, laboratory devices used to amplify DNA by the polymerase chain reaction (PCR). PCR requires the cyclic heating and cooling of samples to specified temperatures. The inclusion of many thermocouples in a small space enables many samples to be amplified in parallel.


title: Thermoelectric effect

text: Thermocouples and thermopiles are devices that use the Seebeck effect to measure the temperature difference between two objects.


title: Thermoelectric effect

text: Thermocouples are often used to measure high temperatures, holding the temperature of one junction constant or measuring it independently (cold junction compensation). Thermopiles use many thermocouples electrically connected in series, for sensitive measurements of very small temperature difference.


title: Thermoelectric effect

text: Peltier dehumidifiers work by forcing damp air across a cold heat sink. As the air passes over the cold surface, it cools and the water vapor contained in it condenses onto the heat sink. The water then drips down into a water tank. The dry air may be forced over another heat sink to cool the hot side of the Peltier cell before being released back into the room.


title: Moiré pattern

text: In mathematics, physics, and art, moiré patterns ( , , ) or moiré fringes are large-scale interference patterns that can be produced when an opaque ruled pattern with transparent gaps is overlaid on another similar pattern. For the moiré interference pattern to appear, the two patterns must not be completely identical, but rather displaced, rotated, or have slightly different pitch.


title: Moiré pattern

text: Moiré patterns appear in many situations. In printing, the printed pattern of dots can interfere with the image. In television and digital photography, a pattern on an object being photographed can interfere with the shape of the light sensors to generate unwanted artifacts. They are also sometimes created deliberately – in micrometers they are used to amplify the effects of very small movements.


title: Moiré pattern

text: In physics, its manifestation is wave interference such as that seen in the double-slit experiment and the beat phenomenon in acoustics.


title: Moiré pattern

text: The term originates from "moire" ("moiré" in its French adjectival form), a type of textile, traditionally made of silk but now also made of cotton or synthetic fiber, with a rippled or "watered" appearance. Moire, or "watered textile", is made by pressing two layers of the textile when wet. The similar but imperfect spacing of the threads creates a characteristic pattern which remains after the fabric dries.


title: Moiré pattern

text: It was a loan of the English "mohair" (attested 1610). In French usage, the noun gave rise to the verb "moirer", "to produce a watered textile by weaving or pressing", by the 18th century.


title: Moiré pattern

text: Moiré patterns are often an artifact of images produced by various digital imaging and computer graphics techniques, for example when scanning a halftone picture or ray tracing a checkered plane (the latter being a special case of aliasing, due to undersampling a fine regular pattern). This can be overcome in texture mapping through the use of mipmapping and anisotropic filtering.


title: Moiré pattern

text: The drawing on the upper right shows a moiré pattern. The lines could represent fibers in moiré silk, or lines drawn on paper or on a computer screen. The nonlinear interaction of the optical patterns of lines creates a real and visible pattern of roughly parallel dark and light bands, the moiré pattern, superimposed on the lines.


title: Moiré pattern

text: The moiré effect also occurs between overlapping transparent objects. For example, an invisible phase mask is made of a transparent polymer with a wavy thickness profile. As light shines through two overlaid masks of similar phase patterns, a broad moiré pattern occurs on a screen some distance away. This phase moiré effect and the classical moiré effect from opaque lines are two ends of a continuous spectrum in optics, which is called the universal moiré effect. The phase moiré effect is the basis for a type of broadband interferometer in x-ray and particle wave applications. It also provides a way to reveal hidden patterns in invisible layers.


title: Moiré pattern

text: Line moiré is one type of moiré pattern; a pattern that appears when superposing two transparent layers containing correlated opaque patterns. Line moiré is the case when the superposed patterns comprise straight or curved lines. When moving the layer patterns, the moiré patterns transform or move at a faster speed. This effect is called optical moiré speedup.


title: Moiré pattern

text: Shape moiré is one type of moiré pattern demonstrating the phenomenon of moiré magnification. 1D shape moiré is the particular simplified case of 2D shape moiré. One-dimensional patterns may appear when superimposing an opaque layer containing tiny horizontal transparent lines on top of a layer containing a complex shape which is periodically repeating along the vertical axis.


title: Moiré pattern

text: Moiré patterns revealing complex shapes, or sequences of symbols embedded in one of the layers (in form of periodically repeated compressed shapes) are created with shape moiré, otherwise called "band moiré" patterns. One of the most important properties of shape moiré is its ability to magnify tiny shapes along either one or both axes, that is, stretching. A common 2D example of moiré magnification occurs when viewing a chain-link fence through a second chain-link fence of identical design. The fine structure of the design is visible even at great distances.


title: Moiré pattern

text: Consider two patterns made of parallel and equidistant lines, e.g., vertical lines. The step of the first pattern is , the step of the second is , with .


title: Moiré pattern

text: If the lines of the patterns are superimposed at the left of the figure, the shift between the lines increases when going to the right. After a given number of lines, the patterns are opposed: the lines of the second pattern are between the lines of the first pattern. If we look from a far distance, we have the feeling of pale zones when the lines are superimposed (there is white between the lines), and of dark zones when the lines are "opposed".


title: Moiré pattern

text: The middle of the first dark zone is when the shift is equal to . The th line of the second pattern is shifted by compared to the th line of the first network. The middle of the first dark zone thus corresponds to


title: Moiré pattern

text: the distance between the middle of two dark zones, which is also the distance between two pale zones, is


title: Moiré pattern

text: The essence of the moiré effect is the (mainly visual) perception of a distinctly different third pattern which is caused by inexact superimposition of two similar patterns. The mathematical representation of these patterns is not trivially obtained and can seem somewhat arbitrary. In this section we shall give a mathematical example of two parallel patterns whose superimposition forms a moiré pattern, and show one way (of many possible ways) these patterns and the moiré effect can be rendered mathematically.


title: Moiré pattern

text: The visibility of these patterns is dependent on the medium or substrate in which they appear, and these may be opaque (as for example on paper) or transparent (as for example in plastic film). For purposes of discussion we shall assume the two primary patterns are each printed in greyscale ink on a white sheet, where the opacity (e.g., shade of grey) of the "printed" part is given by a value between 0 (white) and 1 (black) inclusive, with representing neutral grey. Any value less than 0 or greater than 1 using this grey scale is essentially "unprintable".


title: Moiré pattern

text: We shall also choose to represent the opacity of the pattern resulting from printing one pattern atop the other at a given point on the paper as the average (i.e. the arithmetic mean) of each pattern's opacity at that position, which is half their sum, and, as calculated, does not exceed 1. (This choice is not unique. Any other method to combine the functions that satisfies keeping the resultant function value within the bounds [0,1] will also serve; arithmetic averaging has the virtue of simplicity—with hopefully minimal damage to one's concepts of the printmaking process.)


title: Moiré pattern

text: We now consider the "printing" superimposition of two almost similar, sinusoidally varying, grey-scale patterns to show how they produce a moiré effect in first printing one pattern on the paper, and then printing the other pattern over the first, keeping their coordinate axes in register. We represent the grey intensity in each pattern by a positive opacity function of distance along a fixed direction (say, the x-coordinate) in the paper plane, in the form


title: Moiré pattern

text: where the presence of 1 keeps the function positive definite, and the division by 2 prevents function values greater than 1.


title: Moiré pattern

text: The quantity represents the periodic variation (i.e., spatial frequency) of the pattern's grey intensity, measured as the number of intensity cycles per unit distance. Since the sine function is cyclic over argument changes of , the distance increment per intensity cycle (the wavelength) obtains when , or .


title: Moiré pattern

text: Consider now two such patterns, where one has a slightly different periodic variation from the other:


title: Moiré pattern

text: The average of these two functions, representing the superimposed printed image, evaluates as follows (see reverse identities here :Prosthaphaeresis ):


title: Moiré pattern

text: This function average, , clearly lies in the range [0,1]. Since the periodic variation is the average of and therefore close to and , the moiré effect is distinctively demonstrated by the sinusoidal envelope "beat" function , whose periodic variation is half the difference of the periodic variations and (and evidently much lower in frequency).


title: Moiré pattern

text: Other one-dimensional moiré effects include the classic beat frequency tone which is heard when two pure notes of almost identical pitch are sounded simultaneously. This is an acoustic version of the moiré effect in the one dimension of time: the original two notes are still present—but the listener's "perception" is of two pitches that are the average of and half the difference of the frequencies of the two notes. Aliasing in sampling of time-varying signals also belongs to this moiré paradigm.


title: Moiré pattern

text: Consider two patterns with the same step , but the second pattern is rotated by an angle . Seen from afar, we can also see darker and paler lines: the pale lines correspond to the lines of nodes, that is, lines passing through the intersections of the two patterns.


title: Moiré pattern

text: If we consider a cell of the lattice formed, we can see that it is a rhombus with the four sides equal to ; (we have a right triangle whose hypotenuse is and the side opposite to the angle is ).


title: Moiré pattern

text: The pale lines correspond to the small diagonal of the rhombus. As the diagonals are the bisectors of the neighbouring sides, we can see that the pale line makes an angle equal to with the perpendicular of each pattern's line.


title: Moiré pattern

text: Additionally, the spacing between two pale lines is , half of the long diagonal. The long diagonal is the hypotenuse of a right triangle and the sides of the right angle are and . The Pythagorean theorem gives:


title: Moiré pattern

text: We can see that the smaller is, the farther apart the pale lines; when both patterns are parallel (), the spacing between the pale lines is infinite (there is no pale line).


title: Moiré pattern

text: If we choose to measure the angle, the final error is proportional to the measurement error. If we choose to measure the spacing, the final error is proportional to the inverse of the spacing. Thus, for the small angles, it is best to measure the spacing.


title: Moiré pattern

text: In graphic arts and prepress, the usual technology for printing full-color images involves the superimposition of halftone screens. These are regular rectangular dot patterns—often four of them, printed in cyan, yellow, magenta, and black. Some kind of moiré pattern is inevitable, but in favorable circumstances the pattern is "tight"; that is, the spatial frequency of the moiré is so high that it is not noticeable. In the graphic arts, the term "moiré" means an "excessively visible" moiré pattern. Part of the prepress art consists of selecting screen angles and halftone frequencies which minimize moiré. The visibility of moiré is not entirely predictable. The same set of screens may produce good results with some images, but visible moiré with others.


title: Moiré pattern

text: Moiré patterns are commonly seen on television screens when a person is wearing a shirt or jacket of a particular weave or pattern, such as a houndstooth jacket. This is due to interlaced scanning in televisions and non-film cameras, referred to as interline twitter. As the person moves about, the moiré pattern is quite noticeable. Because of this, newscasters and other professionals who regularly appear on TV are instructed to avoid clothing which could cause the effect.


title: Moiré pattern

text: Photographs of a TV screen taken with a digital camera often exhibit moiré patterns. Since both the TV screen and the digital camera use a scanning technique to produce or to capture pictures with horizontal scan lines, the conflicting sets of lines cause the moiré patterns. To avoid the effect, the digital camera can be aimed at an angle of 30 degrees to the TV screen.


title: Moiré pattern

text: The moiré effect is used in shoreside beacons called "Inogon leading marks" or "Inogon lights", manufactured by Inogon Licens AB, Sweden, to designate the safest path of travel for ships heading to locks, marinas, ports, etc., or to indicate underwater hazards (such as pipelines or cables). The moiré effect creates arrows that point towards an imaginary line marking the hazard or line of safe passage; as navigators pass over the line, the arrows on the beacon appear to become vertical bands before changing back to arrows pointing in the reverse direction. An example can be found in the UK on the eastern shore of Southampton Water, opposite Fawley oil refinery (). Similar moiré effect beacons can be used to guide mariners to the centre point of an oncoming bridge; when the vessel is aligned with the centreline, vertical lines are visible.


title: Moiré pattern

text: Inogon lights are deployed at airports to help pilots on the ground keep to the centreline while docking on stand.


title: Moiré pattern

text: In manufacturing industries, these patterns are used for studying microscopic strain in materials: by deforming a grid with respect to a reference grid and measuring the moiré pattern, the stress levels and patterns can be deduced. This technique is attractive because the scale of the moiré pattern is much larger than the deflection that causes it, making measurement easier.


title: Moiré pattern

text: The moiré effect can be used in strain measurement: the operator just has to draw a pattern on the object, and superimpose the reference pattern to the deformed pattern on the deformed object.


title: Moiré pattern

text: A similar effect can be obtained by the superposition of a holographic image of the object to the object itself: the hologram is the reference step, and the difference with the object are the deformations, which appear as pale and dark lines.


title: Moiré pattern

text: Some image scanner computer programs provide an optional filter, called a "descreen" filter, to remove Moiré-pattern artifacts which would otherwise be produced when scanning printed halftone images to produce digital images.


title: Moiré pattern

text: Many banknotes exploit the tendency of digital scanners to produce moiré patterns by including fine circular or wavy designs that are likely to exhibit a moiré pattern when scanned and printed.


title: Moiré pattern

text: In super-resolution microscopy, the moiré pattern can be used to obtain images with a resolution higher than the diffraction limit, using a technique known as structured illumination microscopy.


title: Moiré pattern

text: In scanning tunneling microscopy, moiré fringes appear if surface atomic layers have a different crystal structure than the bulk crystal. This can for example be due to surface reconstruction of the crystal, or when a thin layer of a second crystal is on the surface, e.g. single-layer, double-layer graphene, or Van der Waals heterostructure of graphene and hBN, or bismuth and antimony nanostructures.


title: Moiré pattern

text: In transmission electron microscopy (TEM), translational moiré fringes can be seen as parallel contrast lines formed in phase-contrast TEM imaging by the interference of diffracting crystal lattice planes that are overlapping, and which might have different spacing and/or orientation. Most of the moiré contrast observations reported in the literature are obtained using high-resolution phase contrast imaging in TEM. However, if probe aberration-corrected high-angle annular dark field scanning transmission electron microscopy (HAADF-STEM) imaging is used, more direct interpretation of the crystal structure in terms of atom types and positions is obtained.


title: Moiré pattern

text: In condensed matter physics, the moiré phenomenon is commonly discussed for two-dimensional materials. The effect occurs when there is mismatch between the lattice parameter or angle of the 2D layer and that of the underlying substrate, or another 2D layer, such as in 2D material heterostructures. The phenomenon is exploited as a means of engineering the electronic structure or optical properties of materials, which some call moiré materials. The often significant changes in electronic properties when twisting two atomic layers and the prospect of electronic applications has led to the name twistronics of this field. A prominent example is in twisted bi-layer graphene, which forms a moiré pattern and at a particular "magic angle" exhibits superconductivity and other important electronic properties.


title: Moiré pattern

text: In materials science, known examples exhibiting moiré contrast are thin films or nanoparticles of MX-type (M = Ti, Nb; X = C, N) overlapping with austenitic matrix. Both phases, MX and the matrix, have face-centered cubic crystal structure and cube-on-cube orientation relationship. However, they have significant lattice misfit of about 20 to 24% (based on the chemical composition of alloy), which produces a moiré effect.


title: Catalysis

text: Catalysis () is the process of increasing the rate of a chemical reaction by adding a substance known as a catalyst (). Catalysts are not consumed in the reaction and remain unchanged after it. If the reaction is rapid and the catalyst recycles quickly, very small amounts of catalyst often suffice; mixing, surface area, and temperature are important factors in reaction rate. Catalysts generally react with one or more reactants to form intermediates that subsequently give the final reaction product, in the process of regenerating the catalyst.


title: Catalysis

text: Catalysis may be classified as either homogeneous, whose components are dispersed in the same phase (usually gaseous or liquid) as the reactant, or heterogeneous, whose components are not in the same phase. Enzymes and other biocatalysts are often considered as a third category.


title: Catalysis

text: Catalysis is ubiquitous in chemical industry of all kinds. Estimates are that 90% of all commercially produced chemical products involve catalysts at some stage in the process of their manufacture.


title: Catalysis

text: The term "catalyst" is derived from Greek , "kataluein", meaning "loosen" or "untie". The concept of catalysis was invented by chemist Elizabeth Fulhame, based on her novel work in oxidation-reduction experiments.


title: Catalysis

text: This reaction proceeds because the reaction products are more stable than the starting material. The uncatalyzed reaction is slow. In fact, the decomposition of hydrogen peroxide is so slow that hydrogen peroxide solutions are commercially available. This reaction is strongly affected by catalysts such as manganese dioxide, or the enzyme peroxidase in organisms. Upon the addition of a small amount of manganese dioxide, the hydrogen peroxide reacts rapidly. This effect is readily seen by the effervescence of oxygen. The manganese dioxide is not consumed in the reaction, and thus may be recovered unchanged, and re-used indefinitely. Accordingly, manganese dioxide "catalyzes" this reaction.


title: Catalysis

text: The SI derived unit for measuring the catalytic activity of a catalyst is the katal, which is quantified in moles per second. The productivity of a catalyst can be described by the turnover number (or TON) and the catalytic activity by the "turn over frequency" (TOF), which is the TON per time unit. The biochemical equivalent is the enzyme unit. For more information on the efficiency of enzymatic catalysis, see the article on "enzymes".


title: Catalysis

text: In general, chemical reactions occur faster in the presence of a catalyst because the catalyst provides an alternative reaction pathway - or mechanism - with a lower activation energy than the non-catalyzed mechanism. In catalyzed mechanisms, the catalyst usually reacts to form an intermediate, which then regenerates the original catalyst in the process.


title: Catalysis

text: As a simple example in the gas phase, the reaction 2 SO + O → 2 SO can be catalyzed by adding nitric oxide. The reaction occurs in two steps:


title: Catalysis

text: An example of heterogeneous catalysis is the reaction of oxygen and hydrogen on the surface of titanium dioxide (TiO, or "titania") to produce water. Scanning tunneling microscopy showed that the molecules undergo adsorption and dissociation. The dissociated, surface-bound O and H atoms diffuse together. The intermediate reaction states are: HO, HO, then HO and the reaction product (water molecule dimers), after which the water molecule desorbs from the catalyst surface.


title: Catalysis

text: Catalysts enable pathways that differ from the uncatalyzed reactions. These pathways have lower activation energy. Consequently, more molecular collisions have the energy needed to reach the transition state. Hence, catalysts can enable reactions that would otherwise be blocked or slowed by a kinetic barrier. The catalyst may increase the reaction rate or selectivity, or enable the reaction at lower temperatures. This effect can be illustrated with an energy profile diagram.


title: Catalysis

text: In the catalyzed elementary reaction, catalysts do not change the extent of a reaction: they have no effect on the chemical equilibrium of a reaction. The ratio of the forward and the reverse reaction rates is unaffected (see also thermodynamics). The second law of thermodynamics describes why a catalyst does not change the chemical equilibrium of a reaction. Suppose there was such a catalyst that shifted an equilibrium. Introducing the catalyst to the system would result in a reaction to move to the new equilibrium, producing energy. Production of energy is a necessary result since reactions are spontaneous only if Gibbs free energy is produced, and if there is no energy barrier, there is no need for a catalyst. Then, removing the catalyst would also result in a reaction, producing energy; i.e. the addition and its reverse process, removal, would both produce energy. Thus, a catalyst that could change the equilibrium would be a perpetual motion machine, a contradiction to the laws of thermodynamics. Thus, catalyst does not alter the equilibrium constant. (A catalyst can however change the equilibrium concentrations by reacting in a subsequent step. It is then consumed as the reaction proceeds, and thus it is also a reactant. Illustrative is the base-catalyzed hydrolysis of esters, where the produced carboxylic acid immediately reacts with the base catalyst and thus the reaction equilibrium is shifted towards hydrolysis.)


title: Catalysis

text: The catalyst stabilizes the transition state more than it stabilizes the starting material. It decreases the kinetic barrier by decreasing the "difference" in energy between starting material and the transition state. It does not change the energy difference between starting materials and products (thermodynamic barrier), or the available energy (this is provided by the environment as heat or light).


title: Catalysis

text: Some so-called catalysts are really precatalysts. Precatalysts convert to catalysts in the reaction. For example, Wilkinson's catalyst RhCl(PPh) loses one triphenylphosphine ligand before entering the true catalytic cycle. Precatalysts are easier to store but are easily activated in situ. Because of this preactivation step, many catalytic reactions involve an induction period.


title: Catalysis

text: In cooperative catalysis, chemical species that improve catalytic activity are called cocatalysts or promoters.


title: Catalysis

text: In autocatalysis, the catalyst "is" a product of the overall reaction, in contrast to all other types of catalysis considered in this article. The simplest example of autocatalysis is a reaction of type A + B → 2 B, in one or in several steps. The overall reaction is just A → B, so that B is a product. But since B is also a reactant, it may be present in the rate equation and affect the reaction rate. As the reaction proceeds, the concentration of B increases and can accelerate the reaction as a catalyst. In effect, the reaction accelerates itself or is autocatalyzed. An example is the hydrolysis of an ester such as aspirin to a carboxylic acid and an alcohol. In the absence of added acid catalysts, the carboxylic acid product catalyzes the hydrolysis.


title: Catalysis

text: A true catalyst can work in tandem with a sacrificial catalyst. The true catalyst is consumed in the elementary reaction and turned into a deactivated form.


title: Catalysis

text: The sacrificial catalyst regenerates the true catalyst for another cycle. The sacrificial catalyst is consumed in the reaction, and as such, it is not really a catalyst, but a reagent. For example, osmium tetroxide (OsO) is a good reagent for dihydroxylation, but it is highly toxic and expensive. In Upjohn dihydroxylation, the sacrificial catalyst N-methylmorpholine N-oxide (NMMO) regenerates OsO, and only catalytic quantities of OsO are needed.


title: Catalysis

text: Catalysis may be classified as either homogeneous or heterogeneous. A homogeneous catalysis is one whose components are dispersed in the same phase (usually gaseous or liquid) as the reactant's molecules. A heterogeneous catalysis is one where the reaction components are not in the same phase. Enzymes and other biocatalysts are often considered as a third category. Similar mechanistic principles apply to heterogeneous, homogeneous, and biocatalysis.


title: Catalysis

text: Heterogeneous catalysts act in a different phase than the reactants. Most heterogeneous catalysts are solids that act on substrates in a liquid or gaseous reaction mixture. Important heterogeneous catalysts include zeolites, alumina, higher-order oxides, graphitic carbon, transition metal oxides, metals such as Raney nickel for hydrogenation, and vanadium(V) oxide for oxidation of sulfur dioxide into sulfur trioxide by the so-called contact process.


title: Catalysis

text: Diverse mechanisms for reactions on surfaces are known, depending on how the adsorption takes place (Langmuir-Hinshelwood, Eley-Rideal, and Mars-van Krevelen). The total surface area of a solid has an important effect on the reaction rate. The smaller the catalyst particle size, the larger the surface area for a given mass of particles.


title: Catalysis

text: A heterogeneous catalyst has active sites, which are the atoms or crystal faces where the reaction actually occurs. Depending on the mechanism, the active site may be either a planar exposed metal surface, a crystal edge with imperfect metal valence, or a complicated combination of the two. Thus, not only most of the volume but also most of the surface of a heterogeneous catalyst may be catalytically inactive. Finding out the nature of the active site requires technically challenging research. Thus, empirical research for finding out new metal combinations for catalysis continues.


title: Catalysis

text: For example, in the Haber process, finely divided iron serves as a catalyst for the synthesis of ammonia from nitrogen and hydrogen. The reacting gases adsorb onto active sites on the iron particles. Once physically adsorbed, the reagents undergo chemisorption that results in dissociation into adsorbed atomic species, and new bonds between the resulting fragments form in part due to their closeness. In this way the particularly strong triple bond in nitrogen is broken, which would be extremely uncommon in the gas phase due to its high activation energy. Thus, the activation energy of the overall reaction is lowered, and the rate of reaction increases. Another place where a heterogeneous catalyst is applied is in the oxidation of sulfur dioxide on vanadium(V) oxide for the production of sulfuric acid.


title: Catalysis

text: Heterogeneous catalysts are typically "supported," which means that the catalyst is dispersed on a second material that enhances the effectiveness or minimizes its cost. Supports prevent or minimize agglomeration and sintering of small catalyst particles, exposing more surface area, thus catalysts have a higher specific activity (per gram) on support. Sometimes the support is merely a surface on which the catalyst is spread to increase the surface area. More often, the support and the catalyst interact, affecting the catalytic reaction. Supports can also be used in nanoparticle synthesis by providing sites for individual molecules of catalyst to chemically bind. Supports are porous materials with a high surface area, most commonly alumina, zeolites or various kinds of activated carbon. Specialized supports include silicon dioxide, titanium dioxide, calcium carbonate, and barium sulfate.


title: Catalysis

text: Many heterogeneous catalysts are in fact nanomaterials. Nanomaterial-based catalysts with enzyme-mimicking activities are collectively called as nanozymes.


title: Catalysis

text: In the context of electrochemistry, specifically in fuel cell engineering, various metal-containing catalysts are used to enhance the rates of the half reactions that comprise the fuel cell. One common type of fuel cell electrocatalyst is based upon nanoparticles of platinum that are supported on slightly larger carbon particles. When in contact with one of the electrodes in a fuel cell, this platinum increases the rate of oxygen reduction either to water or to hydroxide or hydrogen peroxide.


title: Catalysis

text: Homogeneous catalysts function in the same phase as the reactants. Typically homogeneous catalysts are dissolved in a solvent with the substrates. One example of homogeneous catalysis involves the influence of H on the esterification of carboxylic acids, such as the formation of methyl acetate from acetic acid and methanol. High-volume processes requiring a homogeneous catalyst include hydroformylation, hydrosilylation, hydrocyanation. For inorganic chemists, homogeneous catalysis is often synonymous with organometallic catalysts. Many homogeneous catalysts are however not organometallic, illustrated by the use of cobalt salts that catalyze the oxidation of p-xylene to terephthalic acid.


title: Catalysis

text: Whereas transition metals sometimes attract most of the attention in the study of catalysis, small organic molecules without metals can also exhibit catalytic properties, as is apparent from the fact that many enzymes lack transition metals. Typically, organic catalysts require a higher loading (amount of catalyst per unit amount of reactant, expressed in mol% amount of substance) than transition metal(-ion)-based catalysts, but these catalysts are usually commercially available in bulk, helping to lower costs. In the early 2000s, these organocatalysts were considered "new generation" and are competitive to traditional metal(-ion)-containing catalysts. Organocatalysts are supposed to operate akin to metal-free enzymes utilizing, e.g., non-covalent interactions such as hydrogen bonding. The discipline organocatalysis is divided into the application of covalent (e.g., proline, DMAP) and non-covalent (e.g., thiourea organocatalysis) organocatalysts referring to the preferred catalyst-substrate binding and interaction, respectively. The Nobel Prize in Chemistry 2021 was awarded jointly to Benjamin List and David W.C. MacMillan "for the development of asymmetric organocatalysis."


title: Catalysis

text: Photocatalysis is the phenomenon where the catalyst can receive light to generate an excited state that effect redox reactions. Singlet oxygen is usually produced by photocatalysis. Photocatalysts are components of dye-sensitized solar cells.


title: Catalysis

text: In biology, enzymes are protein-based catalysts in metabolism and catabolism. Most biocatalysts are enzymes, but other non-protein-based classes of biomolecules also exhibit catalytic properties including ribozymes, and synthetic deoxyribozymes.


title: Catalysis

text: Biocatalysts can be thought of as an intermediate between homogeneous and heterogeneous catalysts, although strictly speaking soluble enzymes are homogeneous catalysts and membrane-bound enzymes are heterogeneous. Several factors affect the activity of enzymes (and other catalysts) including temperature, pH, the concentration of enzymes, substrate, and products. A particularly important reagent in enzymatic reactions is water, which is the product of many bond-forming reactions and a reactant in many bond-breaking processes.


title: Catalysis

text: In biocatalysis, enzymes are employed to prepare many commodity chemicals including high-fructose corn syrup and acrylamide.


title: Catalysis

text: Some monoclonal antibodies whose binding target is a stable molecule that resembles the transition state of a chemical reaction can function as weak catalysts for that chemical reaction by lowering its activation energy. Such catalytic antibodies are sometimes called "abzymes".


title: Catalysis

text: Estimates are that 90% of all commercially produced chemical products involve catalysts at some stage in the process of their manufacture. In 2005, catalytic processes generated about $900 billion in products worldwide. The global demand for catalysts in 2014 was estimated at US$33.5 billion. Catalysis is so pervasive that subareas are not readily classified. Some areas of particular concentration are surveyed below.


title: Catalysis

text: Petroleum refining makes intensive use of catalysis for alkylation, catalytic cracking (breaking long-chain hydrocarbons into smaller pieces), naphtha reforming and steam reforming (conversion of hydrocarbons into synthesis gas). Even the exhaust from the burning of fossil fuels is treated via catalysis: Catalytic converters, typically composed of platinum and rhodium, break down some of the more harmful byproducts of automobile exhaust.


title: Catalysis

text: With regard to synthetic fuels, an old but still important process is the Fischer-Tropsch synthesis of hydrocarbons from synthesis gas, which itself is processed via water-gas shift reactions, catalyzed by iron. Biodiesel and related biofuels require processing via both inorganic and biocatalysts.


title: Catalysis

text: Some of the largest-scale chemicals are produced via catalytic oxidation, often using oxygen. Examples include nitric acid (from ammonia), sulfuric acid (from sulfur dioxide to sulfur trioxide by the contact process), terephthalic acid from p-xylene, acrylic acid from propylene or propane and acrylonitrile from propane and ammonia.


title: Catalysis

text: The production of ammonia is one of the largest-scale and most energy-intensive processes. In the Haber process nitrogen is combined with hydrogen over an iron oxide catalyst. Methanol is prepared from carbon monoxide or carbon dioxide but using copper-zinc catalysts.


title: Catalysis

text: Bulk polymers derived from ethylene and propylene are often prepared via Ziegler-Natta catalysis. Polyesters, polyamides, and isocyanates are derived via acid-base catalysis.


title: Catalysis

text: Most carbonylation processes require metal catalysts, examples include the Monsanto acetic acid process and hydroformylation.


title: Catalysis

text: Many fine chemicals are prepared via catalysis; methods include those of heavy industry as well as more specialized processes that would be prohibitively expensive on a large scale. Examples include the Heck reaction, and Friedel–Crafts reactions. Because most bioactive compounds are chiral, many pharmaceuticals are produced by enantioselective catalysis (catalytic asymmetric synthesis). (R)-1,2-Propandiol, the precursor to the antibacterial levofloxacin, can be synthesized efficiently from hydroxyacetone by using catalysts based on BINAP-ruthenium complexes, in Noyori asymmetric hydrogenation:


title: Catalysis

text: One of the most obvious applications of catalysis is the hydrogenation (reaction with hydrogen gas) of fats using nickel catalyst to produce margarine. Many other foodstuffs are prepared via biocatalysis (see below).


title: Catalysis

text: Catalysis affects the environment by increasing the efficiency of industrial processes, but catalysis also plays a direct role in the environment. A notable example is the catalytic role of chlorine free radicals in the breakdown of ozone. These radicals are formed by the action of ultraviolet radiation on chlorofluorocarbons (CFCs).


title: Catalysis

text: Generally speaking, anything that increases the rate of a process is a "catalyst", a term derived from Greek καταλύειν, meaning "to annul," or "to untie," or "to pick up." The concept of catalysis was invented by chemist Elizabeth Fulhame and described in a 1794 book, based on her novel work in oxidation-reduction experiments. The first chemical reaction in organic chemistry that used a catalyst was studied in 1811 by Gottlieb Kirchhoff who discovered the acid-catalyzed conversion of starch to glucose. The term "catalysis" was later used by Jöns Jakob Berzelius in 1835 to describe reactions that are accelerated by substances that remain unchanged after the reaction. Fulhame, who predated Berzelius, did work with water as opposed to metals in her reduction experiments. Other 18th century chemists who worked in catalysis were Eilhard Mitscherlich who referred to it as "contact" processes, and Johann Wolfgang Döbereiner who spoke of "contact action. "He developed Döbereiner's lamp, a lighter based on hydrogen and a platinum sponge, which became a commercial success in the 1820s that lives on today. Humphry Davy discovered the use of platinum in catalysis. In the 1880s, Wilhelm Ostwald at Leipzig University started a systematic investigation into reactions that were catalyzed by the presence of acids and bases, and found that chemical reactions occur at finite rates and that these rates can be used to determine the strengths of acids and bases. For this work, Ostwald was awarded the 1909 Nobel Prize in Chemistry. Vladimir Ipatieff performed some of the earliest industrial scale reactions, including the discovery and commercialization of oligomerization and the development of catalysts for hydrogenation.


title: Catalysis

text: An added substance that lowers the rate is called a reaction inhibitor if reversible and catalyst poisons if irreversible. Promoters are substances that increase the catalytic activity, even though they are not catalysts by themselves.


title: Catalysis

text: Inhibitors are sometimes referred to as "negative catalysts" since they decrease the reaction rate. However the term inhibitor is preferred since they do not work by introducing a reaction path with higher activation energy; this would not lower the rate since the reaction would continue to occur by the non-catalyzed path. Instead, they act either by deactivating catalysts or by removing reaction intermediates such as free radicals. In heterogeneous catalysis, coking inhibits the catalyst, which becomes covered by polymeric side products.


title: Catalysis

text: The inhibitor may modify selectivity in addition to rate. For instance, in the hydrogenation of alkynes to alkenes, a palladium (Pd) catalyst partly "poisoned" with lead(II) acetate (Pb(CHCO)) can be used. Without the deactivation of the catalyst, the alkene produced would be further hydrogenated to alkane.


title: Catalysis

text: The inhibitor can produce this effect by, e.g., selectively poisoning only certain types of active sites. Another mechanism is the modification of surface geometry. For instance, in hydrogenation operations, large planes of metal surface function as sites of hydrogenolysis catalysis while sites catalyzing hydrogenation of unsaturates are smaller. Thus, a poison that covers the surface randomly will tend to lower the number of uncontaminated large planes but leave proportionally smaller sites free, thus changing the hydrogenation vs. hydrogenolysis selectivity. Many other mechanisms are also possible.


title: Catalysis

text: Promoters can cover up the surface to prevent the production of a mat of coke, or even actively remove such material (e.g., rhenium on platinum in platforming). They can aid the dispersion of the catalytic material or bind to reagents.


title: Gideon the Ninth

text: Gideon the Ninth is a 2019 science fantasy novel by the New Zealand writer Tamsyn Muir. It is Muir's debut novel and the first in her "Locked Tomb" series, followed by " Harrow the Ninth" (2020), "Nona the Ninth" (2022), and "Alecto the Ninth" (2023).


title: Gideon the Ninth

text: In the star system Dominicus, there are nine planets, each home to a great House which practices its own school of necromancy. The Houses in turn are ruled by the Emperor, an impossibly powerful, immortal necromancer whom they have worshipped as a god for the past ten thousand years. At the start of "Gideon the Ninth," the Emperor invites the heirs of the Nine Houses and their sword-wielding bodyguards (called cavaliers) to undergo a series of trials to become Lyctors. Lyctors are immortal necromancers, revered as saints, who serve as the Emperor's right-hand necromancers in wars against his enemies.


title: Gideon the Ninth

text: The narrative begins with eighteen year-old Gideon Nav's 86th attempt to escape the Ninth House, a death cult tasked with guarding a Locked Tomb said to contain the Emperor's greatest foe, and by whom Gideon was raised in indentured servitude. Her plans of fleeing to join the Emperor's armies (called the Cohort) are quickly foiled by her lifelong antagonist and heiress of the Ninth House, Harrowhark "Harrow" Nonagesimus.


title: Gideon the Ninth

text: Despite their clashing personalities and mutual hatred of each other, Gideon is Harrow's only real choice of cavalier, primarily due to an atmospheric contamination incident around the time of their births that killed the rest of the Ninth House's children. Harrow offers Gideon a commission into the Cohort if she serves as cavalier during the Emperor's trials.


title: Gideon the Ninth

text: Harrow and Gideon travel to Canaan House, a decaying mansion on the planet of the First House, where they meet the heirs and cavaliers of the other Houses. The group is tasked with exploring the mansion to discover the secrets of Lyctorhood.


title: Gideon the Ninth

text: Harrow initially treats Gideon as a liability and disappears for long periods of time to work on her own, leaving Gideon to wander Canaan House and interact with the other Houses. After one such prolonged absence, Gideon goes looking for her, and with the help of the Sixth House finds her in a hidden basement containing a plethora of necromantic experiments left by the Emperor and his original group of Lyctors. It becomes apparent that each House's necromancer and cavalier must work together to complete the puzzles in the basement, so Harrow and Gideon begrudgingly ally. They make quick progress in the trial due to Harrow's exceptional skill in necromancy and Gideon's perceptiveness and combat skills.


title: Gideon the Ninth

text: Following a series of suspicious deaths, the Houses assume that one or more of them are hunting the others. It becomes clear that Canaan House is designed to prevent any one of the Nine Houses from succeeding without collaborating with or combating each other. The surviving Houses turn to bribery, blackmail, and unsteady alliances.


title: Gideon the Ninth

text: Gideon and Harrow's own relationship reaches a low point over Gideon's infatuation with the terminally ill heiress of the Seventh House, Dulcinea Septimus; tensions run high after Gideon discovers the severed head of the Seventh House cavalier among Harrow's things. Gideon takes her suspicions (and the head) to the Sixth House, who in turn confront Dulcinea. Dulcinea explains that the Emperor's call had "caught out" her House; lacking options, she had been using necromancy to move her cavalier's body about like a puppet's since before their arrival at Caanan House.


title: Gideon the Ninth

text: Harrow and Gideon reconcile. Harrow reveals that the atmospheric contamination incident was an intentional human sacrifice by her family in order to create a necromancer powerful enough to save the Ninth House from economic and political failure: herself. (An infant Gideon somehow survived the sacrifice, leading Harrow's parents and the rest of the Ninth House to treat her coldly out of fear.) Harrow is haunted by the hundreds of innocent deaths involved in her creation. Her guilt led her to breach the Locked Tomb as a young girl, where she fell in love with the immaculate corpse of the beautiful girl entombed within. Harrow's family died by suicide upon discovering her heretical trespass; Harrow has been burdened with secretly leading the Ninth House for years. Gideon and Harrow apologize for their treatment of each other. Harrow acknowledges Gideon as her friend, and they pledge a new alliance: "One flesh, one end."


title: Gideon the Ninth

text: The Sixth and the Ninth houses investigate one of the studies in Caanan House. At the same time, the Second House attempts to call the Cohort for backup and intervention, but the Second necromancer is mortally wounded and her cavalier killed by the priests of the First House in the attempt. Meanwhile, the Third House's heiress, Ianthe Tridentarius, deduces how Lyctors are created: a necromancer must extract and devour their cavalier's soul, allowing them to use the soul as a virtually infinite power source and gaining the cavalier's combat skills. Ianthe kills her cavalier without hesitation and becomes a Lyctor, much to the horror of the other Houses. The Eighth House attempts to bring her to justice for the murder of her cavalier, but they are killed when Colum the Eighth is possessed by an angry ghost, who in turn kills his necromancer.


title: Gideon the Ninth

text: After a brief confrontation with Palamedes the Sixth, the Seventh House heiress reveals herself to be an imposter: not Dulcinea the Seventh, but Cytherea the First, one of the Emperor's Lyctors. Cytherea explains that she killed the real Dulcinea and her cavalier shortly before arriving at Caanan House and assumed her identity; likewise, she was the one who killed the Fourth and Fifth Houses, in the hopes that doing so would lure the Emperor back to Caanan House. She intends to "kill [him] and burn his Houses" as part of a revenge plot, starting with the remaining heirs and cavaliers.


title: Gideon the Ninth

text: The survivors battle throughout the House, but Cytherea is apparently invincible. Just as Harrow is about to be killed, Gideon dies by suicide to force Harrow to become a Lyctor. Harrow kills Cytherea before falling unconscious.


title: Gideon the Ninth

text: Harrow wakes up on the Emperor's flagship; she and a wounded Ianthe are the only confirmed survivors of Canaan House. She begs the Emperor to resurrect Gideon, only to learn that Gideon's soul is irreversibly merged with hers. The Emperor reveals that the Empire is in decline and most of the Lyctors have fallen in battle or gone insane. He promises to restore the Ninth House to glory, and in exchange Harrow agrees to serve the Emperor as Harrowhark the First.


title: Gideon the Ninth

text: "Gideon the Ninth" is notable for its writing, which mixes gothic horror with contemporary humor. Muir acknowledges that her writing "includes useless memes and jokes for the reader that nobody in my universe would get." In her review for Vox, Constance Grady commended Muir's ability to slide her "voice seamlessly from Lovecraftian gothic mode into a slangy contemporary mode without ever undercutting one or the other for cheap comedy." Adam Rowe in Forbes also commented on Muir's incorporation of "2019 language tics." In Rowe's interview with Muir, Muir said that the "irreverent tone" was intended "to balance out the horror aspect and some of the heavier, more Gormenghastian stylings." Jason Sheehan's NPR review said of the novel's genre: ""Gideon the Ninth" is too funny to be horror, too gooey to be science fiction, has too many spaceships and autodoors to be fantasy, and has far more bloody dismemberings than your average parlor romance."


title: Gideon the Ninth

text: Muir consulted with writer, HEMA martial artist and fencer Lissa Harris on realistic depictions of swordfighting and combat. The collaboration is reflected in Gideon's journey retraining from a soldier's longsword to a duelist's rapier; Harris herself transitioned from fencing to the longsword. Harris said that Gideon is a "fiendishly talented fighter who is forced to use new and unfamiliar tools, and has to sacrifice some measure of subtlety in favor of crude effectiveness."


title: Gideon the Ninth

text: "Gideon the Ninth" was named one of the best books of 2019 by several publications and organizations, including NPR, Vox, the New York Public Library, "Wired", "Polygon", "Bustle", "Paste", "Shelf Awareness", "Book Riot", and "Gizmodo Australia", and was selected by Amazon's editors as the best science fiction and fantasy book of 2019. It has received endorsements from authors V. E. Schwab, Charles Stross, Robin Sloan, Warren Ellis, Martha Wells, Amal El-Mohtar, Kiersten White, Annalee Newitz, Genevieve Cogman, Kameron Hurley, Django Wexler, Yoon Ha Lee, Rebecca Roanhorse, Richard Kadrey, Rin Chupeco, Max Gladstone, and Brooke Bolander.


title: Gideon the Ninth

text: Writing in "The New York Times", El-Mohtar called "Gideon the Ninth" a "devastating debut that deserves every ounce of hype it’s received" and praised it as "deft, tense and atmospheric, compellingly immersive and wildly original."


title: Gideon the Ninth

text: Liz Bourke and Carolyn Cushman gave a more critical review in "Locus", saying that the novel failed "in its interrogation of the central hate-co-dependence-need relationship between Gideon and Harrow." Despite this, "Gideon the Ninth" won the 2020 Locus Award for Best First Novel.


title: Gideon the Ninth

text: The novel was also shortlisted for the 2020 Nebula Award for Best Novel, the 2020 World Fantasy Award, and the 2020 Hugo Award for Best Novel.


title: Gideon the Ninth

text: In 2021, NPR listed "Gideon the Ninth" and the Locked Tomb series as one of the 50 best science fiction and fantasy books of the 2010s.


title: 1997 in film

text: The year 1997 in film involved many significant films, including "Titanic", "The Full Monty", "Gattaca", "Donnie Brasco", "Good Will Hunting", "L.A. Confidential", "The Fifth Element", "Nil by Mouth", "The Spanish Prisoner", and the beginning of the film studio DreamWorks.


title: Los Alamos National Laboratory

text: Los Alamos National Laboratory (often shortened as Los Alamos and LANL) is one of the sixteen research and development laboratories of the United States Department of Energy (DOE), located a short distance northwest of Santa Fe, New Mexico, in the American southwest. Best known for its central role in helping develop the first atomic bomb, LANL is one of the world's largest and most advanced scientific institutions.


title: Los Alamos National Laboratory

text: Los Alamos was established in 1943 as a top-secret site for designing nuclear weapons under the Manhattan Project during World War II. Selected for its remote yet relatively accessible location, it was initially known as Project Y and served as the main hub for conducting and coordinating nuclear research; other labs, today known as Oak Ridge National Laboratory and the Hanford Site, concentrated on the production of uranium and plutonium bomb fuels. Los Alamos was the heart of the project, bringing together some of the world's most famous scientists, among them numerous Nobel Prize winners.


title: Los Alamos National Laboratory

text: The lab's existence was made public after the war ended, when it became known universally as Los Alamos. In 1952, the Atomic Energy Commission formed a second design lab under the direction of the University of California, Berkeley, becoming the Lawrence Livermore National Laboratory (LLNL). The two labs have since competed on a wide variety of bomb designs. With the end of the Cold War, both labs have focused increasingly on civilian missions.


title: Los Alamos National Laboratory

text: Today, Los Alamos is one of the largest science and technology institutions in the world. It conducts multidisciplinary research in fields such as national security, space exploration, nuclear fusion, renewable energy, medicine, nanotechnology, and supercomputing. The town of Los Alamos, New Mexico, directly north of the lab, grew extensively through this period.


title: Los Alamos National Laboratory

text: After several reorganizations, LANL is currently privately managed and operated by Triad National Security, LLC.


title: Los Alamos National Laboratory

text: The laboratory was founded during World War II as a secret, centralized facility to coordinate the scientific research of the Manhattan Project, the Allied project to develop the first nuclear weapons. In September 1942, the difficulties encountered in conducting preliminary studies on nuclear weapons at universities scattered across the country indicated the need for a laboratory dedicated solely to that purpose.


title: Los Alamos National Laboratory

text: General Leslie Groves wanted a central laboratory at an isolated location for safety, and to keep the scientists away from the populace. It should be at least 200 miles from international boundaries and west of the Mississippi. Major John Dudley suggested Oak City, Utah or Jemez Springs, New Mexico but both were rejected. Jemez Springs was only a short distance from the current site. Project Y director J. Robert Oppenheimer had spent much time in his youth in the New Mexico area, and suggested the Los Alamos Ranch School on the mesa. Dudley had rejected the school as not meeting Groves’ criteria, but as soon as Groves saw it he said in effect "This is the place". Oppenheimer became the laboratory's first director.


title: Los Alamos National Laboratory

text: During the Manhattan Project, Los Alamos hosted thousands of employees, including many Nobel Prize-winning scientists. The location was a total secret. Its only mailing address was a post office box, number 1663, in Santa Fe, New Mexico. Eventually two other post office boxes were used, 180 and 1539, also in Santa Fe. Though its contract with the University of California was initially intended to be temporary, the relationship was maintained long after the war. Until the atomic bombings of Hiroshima and Nagasaki, Japan, University of California president Robert Sproul did not know what the purpose of the laboratory was and thought it might be producing a "death ray". The only member of the UC administration who knew its true purpose—indeed, the only one who knew its exact physical location—was the Secretary-Treasurer Robert Underhill, who was in charge of wartime contracts and liabilities.


title: Los Alamos National Laboratory

text: The work of the laboratory culminated in several atomic devices, one of which was used in the first nuclear test near Alamogordo, New Mexico, codenamed "Trinity", on July 16, 1945. The other two were weapons, "Little Boy" and "Fat Man", which were used in the attacks on Hiroshima and Nagasaki. The Laboratory received the Army-Navy ‘E’ Award for Excellence in production on October 16, 1945.


title: Los Alamos National Laboratory

text: After the war, Oppenheimer retired from the directorship, and it was taken over by Norris Bradbury, whose initial mission was to make the previously hand-assembled atomic bombs "G.I. proof" so that they could be mass-produced and used without the assistance of highly trained scientists. Many of the original Los Alamos "luminaries" chose to leave the laboratory, and some even became outspoken opponents to the further development of nuclear weapons.


title: Los Alamos National Laboratory

text: The name officially changed to the Los Alamos Scientific Laboratory on January 1, 1947. By this time, Argonne had already been made the first National Laboratory the previous year. Los Alamos would not become a National Laboratory in name until 1981.


title: Los Alamos National Laboratory

text: In the years since the 1940s, Los Alamos was responsible for the development of the hydrogen bomb, and many other variants of nuclear weapons. In 1952, Lawrence Livermore National Laboratory was founded to act as Los Alamos' "competitor", with the hope that two laboratories for the design of nuclear weapons would spur innovation. Los Alamos and Livermore served as the primary classified laboratories in the U.S. national laboratory system, designing all the country's nuclear arsenal. Additional work included basic scientific research, particle accelerator development, health physics, and fusion power research as part of Project Sherwood. Many nuclear tests were undertaken in the Marshall Islands and at the Nevada Test Site. During the late-1950s, a number of scientists including Dr. J. Robert "Bob" Beyster left Los Alamos to work for General Atomics (GA) in San Diego.


title: Los Alamos National Laboratory

text: Three major nuclear-related accidents have occurred at LANL. Criticality accidents occurred in August 1945 and May 1946, and a third accident occurred during an annual physical inventory in December 1958.


title: Los Alamos National Laboratory

text: Several buildings associated with the Manhattan Project at Los Alamos were declared a National Historic Landmark in 1965.


title: Los Alamos National Laboratory

text: At the end of the Cold War, both labs went through a process of intense scientific diversification in their research programs to adapt to the changing political conditions that no longer required as much research towards developing new nuclear weapons and has led the lab to increase research for "non-war" science and technology. Los Alamos' nuclear work is currently thought to relate primarily to computer simulations and stockpile stewardship. The development of the Dual-Axis Radiographic Hydrodynamic Test Facility will allow complex simulations of nuclear tests to take place without full explosive yields.


title: Los Alamos National Laboratory

text: The laboratory contributed to the early development of the flow cytometry technology. In the 1950s, researcher Mack Fulwyler developed a technique for sorting erythrocytes that combined the Coulter Principle of Coulter counter technologies, which measures the presence of cells and their size, with ink jet technology, which produces a laminar flow of liquid that breaks up into separate, fine drops. In 1969, Los Alamos reported the first fluorescence detector apparatus, which accurately measured the number and size of ovarian cells and blood cells.


title: Los Alamos National Laboratory

text: As of 2017, other research performed at the lab included developing cheaper, cleaner bio-fuels and advancing scientific understanding around renewable energy.


title: Los Alamos National Laboratory

text: Non-nuclear national security and defense development is also a priority at the lab. This includes preventing outbreaks of deadly diseases by improving detection tools and the monitoring the effectiveness of the United States’ vaccine distribution infrastructure. Additional advancements include the ASPECT airplane that can detect bio threats from the sky.


title: Los Alamos National Laboratory

text: In 2008, development for a safer, more comfortable and accurate test for breast cancer was ongoing by scientists Lianjie Huang and Kenneth M. Hanson and collaborators. The new technique, called ultrasound-computed tomography (ultrasound CT), uses sound waves to accurately detect small tumors that traditional mammography cannot.


title: Los Alamos National Laboratory

text: The lab has made intense efforts for humanitarian causes through its scientific research in medicine. In 2010, three vaccines for the Human Immunodeficiency Virus were being tested by lab scientist Bette Korber and her team. "These vaccines might finally deal a lethal blow to the AIDS virus", says Chang-Shung Tung, leader of the Lab's Theoretical Biology and Biophysics group.


title: Los Alamos National Laboratory

text: The laboratory has attracted negative publicity from a number of events. In 1999, Los Alamos scientist Wen Ho Lee was accused of 59 counts of mishandling classified information by downloading nuclear secrets—"weapons codes" used for computer simulations of nuclear weapons tests—to data tapes and removing them from the lab. After ten months in jail, Lee pleaded guilty to a single count and the other 58 were dismissed with an apology from U.S. District Judge James Parker for his incarceration. Lee had been suspected for having shared U.S. nuclear secrets with China, but investigators were never able to establish what Lee did with the downloaded data. In 2000, two computer hard drives containing classified data were announced to have gone missing from a secure area within the laboratory, but were later found behind a photocopier.


title: Los Alamos National Laboratory

text: Los Alamos National Laboratory's mission is to "solve national security challenges through simultaneous excellence". The laboratory's strategic plan reflects U.S. priorities spanning nuclear security, intelligence, defense, emergency response, nonproliferation, counterterrorism, energy security, emerging threats, and environmental management. This strategy is aligned with priorities set by the Department of Energy (DOE), the National Nuclear Security Administration (NNSA), and national strategy guidance documents, such as the Nuclear Posture Review, the National Security Strategy, and the Blueprint for a Secure Energy Future


title: Los Alamos National Laboratory

text: Los Alamos is the senior laboratory in the DOE system, and executes work in all areas of the DOE mission: national security, science, energy, and environmental management. The laboratory also performs work for the Department of Defense (DoD), Intelligence Community (IC), and Department of Homeland Security (DHS), among others.


title: Los Alamos National Laboratory

text: The laboratory's multidisciplinary scientific capabilities and activities are organized into six Capability Pillars:


title: Los Alamos National Laboratory

text: As of 2017, the Los Alamos National Laboratory is using data and algorithms to possibly protect public health by tracking the growth of infectious diseases. Digital epidemiologists at the lab's Information Systems and Modeling group are using clinical surveillance data, Google search queries, census data, Wikipedia, and even tweets to create a system that could predict epidemics. The team is using data from Brazil as its model; Brazil was notably threatened by the Zika virus as it prepared to host the Summer Olympics in 2016.


title: Los Alamos National Laboratory

text: Around LANL's 43-square-mile property are 2,000 dumpsites which have permanently contaminated the environment. It also contributed to thousands of dumpsites at 108 locations in 29 US states.


title: Los Alamos National Laboratory

text: Continuing efforts to make the laboratory more efficient led the Department of Energy to open its contract with the University of California to bids from other vendors in 2003. Though the university and the laboratory had difficult relations many times since their first World War II contract, this was the first time that the university ever had to compete for management of the laboratory. The University of California decided to create a private company with the Bechtel Corporation, Washington Group International, and the BWX Technologies to bid on the contract to operate the laboratory. The UC/Bechtel led corporation—Los Alamos National Security, LLC (LANS)—was pitted against a team formed by the University of Texas System partnered with Lockheed-Martin. In December 2005, the Department of Energy announced that LANS had won the next seven-year contract to manage and operate the laboratory.


title: Los Alamos National Laboratory

text: On June 1, 2006, the University of California ended its sixty years of direct involvement in operating Los Alamos National Laboratory, and management control of the laboratory was taken over by Los Alamos National Security, LLC with effect October 1, 2007. Approximately 95% of the former 10,000 plus UC employees at LANL were rehired by LANS to continue working at LANL. Other than UC appointing three members to the eleven member board of directors that oversees LANS, UC now has virtually no responsibility or direct involvement in LANL. UC policies and regulations that apply to UC campuses and its two national laboratories in California (Lawrence Berkeley and Lawrence Livermore) no longer apply to LANL, and the LANL director no longer reports to the UC Regents or UC Office of the President. Also, LANL employees were removed from the UC's 403(b) retirement savings and defined benefits pension program and placed in a LANS run program. While the LANS retirement program provides rehired UC employees with pensions similar to those UC would have given them, LANS no longer guarantees full pensions to newly hired LANL employees. It now provides basic 401(k) retirement saving options.


title: Los Alamos National Laboratory

text: On June 8, 2018, the NNSA announced that Triad National Security, LLC, a joint venture between Battelle Memorial Institute, the University of California, and Texas A&M University, would assume operation and management of LANL beginning November 1, 2018.


title: Los Alamos National Laboratory

text: In August 2011, a near criticality incident happened with eight rods of plutonium placed close to each other to take a photo. In the aftermath, 12 of 14 of the lab's safety staff left in anger about their advice being dismissed by the management. Without safety management, the Plutonium Facility PF-4 was shut down in 2013 and is still closed in 2017 because the lab fails to meet expectations. As a consequence, the U.S. Department of Energy, sought alternative suppliers the LANL's management contract.


title: Los Alamos National Laboratory

text: The lab was penalized with a $57 million reduction in its 2014 budget over the February 14, 2014 accident at the Waste Isolation Pilot Plant for which it was partly responsible.


title: Los Alamos National Laboratory

text: In August 2017, the improper storage of plutonium metal could have triggered a criticality accident, and subsequently staff failed to declare the failure as required by procedure.


title: Los Alamos National Laboratory

text: With support of the National Science Foundation, LANL operates one of the three National High Magnetic Field Laboratories in conjunction with and located at two other sites Florida State University in Tallahassee, Florida, and University of Florida in Gainesville, Florida.


title: Los Alamos National Laboratory

text: Los Alamos National Laboratory is a partner in the Joint Genome Institute (JGI) located in Walnut Creek, California. JGI was founded in 1997 to unite the expertise and resources in genome mapping, DNA sequencing, technology development, and information sciences pioneered at the three genome centers at University of California's Lawrence Berkeley National Laboratory (LBNL), Lawrence Livermore National Laboratory (LLNL), and LANL.


title: Los Alamos National Laboratory

text: The Integrated Computing Network (ICN) is a multi-security level network at the LANL integrating large host supercomputers, a file server, a batch server, a printer and graphics output server and numerous other general purpose and specialized systems. IBM Roadrunner, which was part of this network, was the first supercomputer to hit petaflop speeds.


title: Los Alamos National Laboratory

text: Until 1999, The Los Alamos National Laboratory hosted the arXiv e-print archive. The arXiv is currently operated and funded by Cornell University.


title: Los Alamos National Laboratory

text: In the recent years, the Laboratory has developed a major research program in systems biology modeling, known at LANL under the name q-bio.


title: Los Alamos National Laboratory

text: LANL also published "Los Alamos Science" from 1980 to 2005, as well as the "Nuclear Weapons Journal" which was replaced by "National Security Science" after 2 issues in 2009.


title: Los Alamos National Laboratory

text: In 2005, Congress held new hearings on lingering security issues at Los Alamos National Weapons Laboratory in New Mexico; documented problems continued to be ignored.


title: Los Alamos National Laboratory

text: In November 2008 a drum containing nuclear waste was ruptured due to a 'deflagration' according to an inspector general report of the Dept. of Energy, which due to lab mistakes, also occurred in 2014 at the Carlsbad plant with significant disruptions and costs across the industry.


title: Los Alamos National Laboratory

text: In 2009, 69 computers which did not contain classified information were lost. The same year also saw a scare in which 1 kg (2.2 lb) of missing plutonium prompted a Department of Energy investigation into the laboratory. The investigation found that the "missing plutonium" was a result of miscalculation by LANL's statisticians and did not actually exist; but the investigation did lead to heavy criticism of the laboratory by the DOE for security flaws and weaknesses that the DOE claimed to have found.


title: Los Alamos National Laboratory

text: LANL is northern New Mexico's largest institution and the largest employer with approximately 8,762 direct employees, 277 guard force, 505 contractors, 1,613 students, 1,143 unionized craft workers, and 452 post-doctoral researchers. Additionally, there are roughly 120 DOE employees stationed at the laboratory to provide federal oversight of LANL's work and operations. Approximately one-third of the laboratory's technical staff members are physicists, one quarter are engineers, one-sixth are chemists and materials scientists, and the remainder work in mathematics and computational science, biology, geoscience, and other disciplines. Professional scientists and students also come to Los Alamos as visitors to participate in scientific projects. The staff collaborates with universities and industry in both basic and applied research to develop resources for the future. The annual budget is approximately US$2.2 billion.


title: Los Alamos National Laboratory

text: In the hit TV show "Breaking Bad", the protagonist Walter White is a former employee of the Los Alamos National Laboratory.


title: Igor Sikorsky

text: Igor Ivanovich Sikorsky (, "Ígor' Ivánovich Sikórskiy"; May 25, 1889 – October 26, 1972) was a Russian–American aviation pioneer in both helicopters and fixed-wing aircraft. His first success came with the S-2, the second aircraft of his design and construction. His fifth airplane, the S-5, won him national recognition as well as F.A.I. license number 64. His S-6-A received the highest award at the 1912 Moscow Aviation Exhibition, and in the fall of that year the aircraft won first prize for its young designer, builder and pilot in the military competition at Saint Petersburg.


title: Igor Sikorsky

text: After immigrating to the United States in 1919, Sikorsky founded the Sikorsky Aircraft Corporation in 1923, and developed the first of Pan American Airways' ocean-crossing flying boats in the 1930s.


title: Igor Sikorsky

text: In 1939, Sikorsky designed and flew the Vought-Sikorsky VS-300, the first viable American helicopter, which pioneered the rotor configuration used by most helicopters today. Sikorsky modified the design into the Sikorsky R-4, which became the world's first mass-produced helicopter in 1942.


title: Igor Sikorsky

text: Igor Sikorsky was born in Kiev, Russian Empire (now Kyiv, Ukraine) on May 25, 1889. He was the youngest of five children. His father, Ivan Alexeevich Sikorsky, was a professor of psychology in Saint Vladimir University (now Taras Shevchenko National University), a psychiatrist with an international reputation, and an ardent Russian nationalist.


title: Igor Sikorsky

text: Igor Sikorsky was an Orthodox Christian. When questioned regarding his roots, he would answer: "My family is of Russian origin. My grandfather and other ancestors from the time of Peter the Great were Russian Orthodox priests."


title: Igor Sikorsky

text: Sikorsky's mother, Mariya Stefanovna Sikorskaya (née Temryuk-Cherkasova), was a physician who did not work professionally. She is sometimes called Zinaida Sikorsky. While homeschooling young Igor, she gave him a great love for art, especially in the life and work of Leonardo da Vinci, and the stories of Jules Verne. In 1900, at age 11, he accompanied his father to Germany and through conversations with his father, became interested in natural sciences. After returning home, Sikorsky began to experiment with model flying machines, and by age 12, he had made a small rubber band-powered helicopter.


title: Igor Sikorsky

text: Sikorsky began studying at the Saint Petersburg Maritime Cadet Corps, in 1903, at the age of 14. In 1906, he determined that his future lay in engineering, so he resigned from the academy, despite his satisfactory standing, and left the Russian Empire to study in Paris. He returned to the Russian Empire in 1907, enrolling at the Mechanical College of the Kyiv Polytechnic Institute. After the academic year, Sikorsky again accompanied his father to Germany in the summer of 1908, where he learned of the accomplishments of the Wright brothers' Flyer and Ferdinand von Zeppelin's rigid airships. Sikorsky later said about this event: "Within twenty-four hours, I decided to change my life's work. I would study aviation."


title: Igor Sikorsky

text: By the start of World War I in 1914, Sikorsky's airplane research and production business in Kyiv was flourishing, and his factory made bombers during the war. After the Russian revolution in 1917, Igor Sikorsky fled his homeland in early 1918, because the Bolsheviks threatened to shoot him for being "the Tsar's friend and a very popular person". He moved to France where he was offered a contract for the design of a new, more powerful Muromets-type plane. But in November 1918 the war ended and the French government stopped subsidizing military orders, and so he decided to move to the United States. On March 24, 1919 he left France on the ocean liner "Lorraine" arriving in New York City on March 30, 1919.


title: Igor Sikorsky

text: With financial backing from his sister Olga, Sikorsky returned to Paris, the center of the aviation world at the time, in 1909. Sikorsky met with aviation pioneers, to ask them questions about aircraft and flying. In May 1909, he returned to Russia and began designing his first helicopter, which he began testing in July 1909. Powered by a 25 horsepower Anzani engine, the helicopter used an upper and lower two-bladed lifting propeller that rotated in opposite directions at 160 rpm. The machine could only generate about of lift, not enough to lift the approximate weight. Despite his progress in solving technical problems of control, Sikorsky realized that the aircraft would never fly. He finally disassembled the aircraft in October 1909, after he determined that he could learn nothing more from the design. In February 1910, he undertook to build a second helicopter, and his first airplane. By the spring, helicopter No. 2 could lift its weight of , but not the additional weight of an operator.


title: Igor Sikorsky

text: I had learned enough to recognize that with the existing state of the art, engines, materials, and – most of all – the shortage of money and lack of experience... I would not be able to produce a successful helicopter at that time.


title: Igor Sikorsky

text: Sikorsky's first aircraft of his own design, the S-1 used a 15 hp Anzani 3-cylinder fan engine in a pusher configuration, that could not lift the aircraft. His second design called the S-2 was powered by a 25 hp Anzani engine in a tractor configuration and first flew on June 3, 1910 at a height of a few feet. On June 30 after some modifications, Sikorsky reached an altitude of "sixty or eighty feet" before the S-2 stalled and was completely destroyed when it crashed in a ravine. Later, Sikorsky built the two-seat S-5, his first design not based on other European aircraft. Flying this original aircraft, Sikorsky earned his pilot license; Fédération Aéronautique Internationale (FAI) license No. 64 issued by the Imperial Aero Club of Russia in 1911. During a demonstration of the S-5, the engine quit and Sikorsky was forced to make a crash landing to avoid a wall. It was discovered that a mosquito in the gasoline had been drawn into the carburetor, starving the engine of fuel. The close call convinced Sikorsky of the need for an aircraft that could continue flying if it lost an engine. His next aircraft, the S-6 held three passengers and was selected as the winner of the Moscow aircraft exhibition held by the Russian Army in February 1912.


title: Igor Sikorsky

text: In early 1912, Igor Sikorsky became Chief Engineer of the aircraft division for the Russian Baltic Railroad Car Works ("Russko-Baltiisky Vagonny Zavod" or "R-BVZ") in Saint Petersburg. His work at R-BVZ included the construction of the first four-cylinder aircraft, the S-21 "Russky Vityaz", which he initially called "Le Grand" when fitted with just two engines, then the "Bolshoi Baltisky" (The Great Baltic) when fitted with four engines in two "push-pull" pairs, and finally "Russki Vityaz" in its four engine all tractor-engined configuration. He also served as the test pilot for its first flight on May 13, 1913. In recognition for his accomplishment, he was awarded an honorary degree in engineering from Saint Petersburg Polytechnical Institute in 1914. Sikorsky took the experience from building the Russky Vityaz to develop the S-22 "Ilya Muromets" airliner. Due to outbreak of World War I, he redesigned it as the world's first four-engined bomber, for which he was decorated with the Order of St. Vladimir.


title: Igor Sikorsky

text: After World War I, Igor Sikorsky briefly became an engineer for the French forces in Russia, during the Russian Civil War. Seeing little opportunity for himself as an aircraft designer in war-torn Europe, and particularly Russia, ravaged by the Bolshevik Revolution and Russian Civil War, he emigrated to the United States, arriving in New York on March 30, 1919.


title: Igor Sikorsky

text: In the U.S., Sikorsky first worked as a school teacher and a lecturer, while looking for an opportunity to work in the aviation industry. In 1932, he joined the faculty of the University of Rhode Island to form an aeronautical engineering program and remained with the university until 1948. He also lectured at the University of Bridgeport.


title: Igor Sikorsky

text: In 1923, Sikorsky formed the Sikorsky Manufacturing Company in Roosevelt, New York. He was helped by several former Russian military officers. Among Sikorsky's chief supporters was composer Sergei Rachmaninoff, who introduced himself by writing a check for US$5,000 (approximately $61,000 in 2007). Although his prototype was damaged in its first test flight, Sikorsky persuaded his reluctant backers to invest another $2,500. With the additional funds, he produced the S-29, one of the first twin-engine aircraft in the US, with a capacity for 14 passengers and a speed of 115 mph. The performance of the S-29, slow compared to military aircraft of 1918, proved to be a "make or break" moment for Sikorsky's funding.


title: Igor Sikorsky

text: In 1928, Sikorsky became a naturalized citizen of the United States. The Sikorsky Manufacturing Company moved to Stratford, Connecticut in 1929. It became a part of the United Aircraft and Transport Corporation (now United Technologies Corporation) in July of that year. The company manufactured flying boats, such as the S-42 "Clipper", used by Pan Am for transatlantic flights.


title: Igor Sikorsky

text: Meanwhile, Sikorsky also continued his earlier work on vertical flight while living in Nichols, Connecticut. On February 14, 1929, he filed an application to patent a "direct lift" amphibian aircraft which used compressed air to power a direct lift "propeller" and two smaller propellers for thrust. On June 27, 1931, Sikorsky filed for a patent for another "direct lift aircraft", and was awarded patent No. 1,994,488 on March 19, 1935. His design plans eventually culminated in the first (tethered) flight of the Vought-Sikorsky VS-300 on September 14, 1939, with the first free flight occurring eight months later on May 24, 1940. Sikorsky's success with the VS-300 led to the R-4, which became the world's first mass-produced helicopter, in 1942. Sikorsky's final VS-300 rotor configuration, comprising a single main rotor and a single antitorque tail rotor, has proven to be one of the most popular helicopter configurations, being used in most helicopters produced today.


title: Igor Sikorsky

text: Sikorsky was married to Olga Fyodorovna Simkovitch in the Russian Empire. They were divorced and Olga remained in Russia with their daughter, Tania, as Sikorsky departed after the Bolshevik Revolution in 1917. In 1923, Sikorsky's sisters immigrated to the US, bringing six-year-old Tania with them. Sikorsky married Elisabeth Semion (1903–1995) in 1924, in New York. Sikorsky and Elisabeth had four sons; Sergei, Nikolai, Igor Jr. and George.


title: Igor Sikorsky

text: Sikorsky died at his home in Easton, Connecticut, on October 26, 1972, and is buried in Saint John the Baptist Russian Orthodox Cemetery located on Nichols Avenue in Stratford.


title: Igor Sikorsky

text: Sikorsky's and Andrei Tupolev's professional careers were covered in the 1979 Soviet biopic "The Poem of Wings" () where Sikorsky was portrayed by Yury Yakovlev. A working model of Sikorsky Ilya Muromets was recreated for filming.


title: Igor Sikorsky

text: The Sikorsky Memorial Bridge, which carries the Merritt Parkway across the Housatonic River next to the Sikorsky corporate headquarters, is named for him. Sikorsky has been designated a Connecticut Aviation Pioneer by the Connecticut State Legislature. The Sikorsky Aircraft Corporation in Stratford, Connecticut, continues to the present day as one of the world's leading helicopter manufacturers, and a nearby small airport has been named Sikorsky Memorial Airport.


title: Igor Sikorsky

text: Sikorsky was inducted into the National Inventors Hall of Fame and the Junior Achievement U.S. Business Hall of Fame in 1987.


title: Igor Sikorsky

text: In October 2011, one of the streets in Kyiv was renamed after Sikorsky. The decision was made by the City Council at the request of the U.S. Embassy in Ukraine, which opened its new office on that street. The Sikorsky's family house in the city's historical center is preserved to this day but is in a neglected condition pending restoration.


title: Igor Sikorsky

text: In November 2012, one of the Russian supersonic heavy strategic bomber Tu-160, based at the Engels-2 Air Force Base, was named for Igor Sikorsky, which caused controversy among air base crew members. One of the officers said that Igor Sikorsky does not deserve it because he laid the foundations of the U.S., rather than Russian aviation. However, the Long Range Aviation command officer said that Igor Sikorsky is not responsible for the activities of his military aircraft, noted that Sikorsky had also designed the first heavy bomber for Russia. In 2013, "Flying" magazine ranked Sikorsky number 12 on its list of the 51 Heroes of Aviation.


title: Igor Sikorsky

text: In August 2016, the National technical university of Ukraine "Kyiv politechnical institute" was named "National Technical University of Ukraine "Igor Sikorsky Kyiv Polytechnic Institute"" its former student and outstanding aircraft designer.


title: Igor Sikorsky

text: On March 22, 2018, the Kyiv City Council officially renamed Kyiv International Airport to "Igor Sikorsky Kyiv International Airport Zhuliany".


title: Igor Sikorsky

text: Sikorsky was a deeply religious Russian Orthodox Christian and authored two religious and philosophical books ("The Message of the Lord's Prayer" and "The Invisible Encounter"). Summarizing his beliefs, in the latter he wrote:


title: Nova (Richard Rider)

text: Nova (Richard Rider) is a fictional character appearing in American comic books published by Marvel Comics. The character appeared historically as the star of his own series, and at other times, as a supporting character in team books such as "The New Warriors". He is a member of the intergalactic police force known as the Nova Corps, for which he gained superhuman abilities including enhanced strength, flight and resistance to injury.


title: Nova (Richard Rider)

text: The character was created in 1966 by writer Marv Wolfman in issue #3 of his fanzine, "Super Adventures". Then known as The Star, he was an alien doctor named Denteen who found a spaceship containing pills which gave him a different superhuman power every five minutes. In issue #6, Wolfman and writer Len Wein reimagined the character, now a prisoner named Kraken Roo who turns out to become the superhero Black Nova. Years later, Wolfman (working for Marvel Comics) and artist John Romita Sr. tweaked the design of the character's uniform and created a new origin story.


title: Nova (Richard Rider)

text: Nova debuted in "The Man Called Nova" #1 (Sept 1976), written by Wolfman and drawn by John Buscema. Wolfman intended the teenage character to be an homage to Stan Lee and Steve Ditko's Spider-Man, down to his humble working-class roots and alliterative alter-ego. The original series lasted 25 issues from September 1976 to May 1979. Dangling plot lines were resolved in issues 206-214 of "Fantastic Four" (also by Wolfman) and issue 24 of "Rom the Spaceknight". The character then disappeared into obscurity until returning as a member of the original New Warriors team debuting in "The Mighty Thor "#411 (December 1989), and continuing through "The New Warriors" #1-75, Annual #1-4 (July 1990—September 1996).


title: Nova (Richard Rider)

text: Following two subsequent "Nova" titles, "Nova" vol. 2 #1-18 (Jan. 94-June 95) and "Nova, The Human Rocket" vol. 3 #1-7 (May.-Nov. 1999), Nova would return in "The New Warriors" vol. 2 #0-10 (Oct. 1999—July 2000) and "New Warriors" vol. 3 #1-6 (July 2005-Dec. 2005). After a four issue miniseries titled "Annihilation: Nova" and a leading role in "Annihilation" 1-6, a fourth volume of "Nova" ran for 36 issues (April 2007-April 2010). This series tied into "", "Secret Invasion", and "War of Kings". After the cancellation of volume four, some remaining plot threads were addressed in "The Thanos Imperative", a six-issue miniseries with two bookend one-shots (May 2010-Feb. 2011).


title: Nova (Richard Rider)

text: Nova appeared as a member of the Secret Avengers during the first four issues of that team's eponymous series (May - Aug 2010).


title: Nova (Richard Rider)

text: Nova appears in a "Guardians of the Galaxy" storyline running from August to October 2014, an "Original Sin" tie-in featuring a flashback to events immediately following "The Thanos Imperative".


title: Nova (Richard Rider)

text: When the last surviving member of the planet Xandar's elite Nova Corps, Rhomann Dey, is dying, he selects New York high school student Richard Rider to replace him. Rider is given the uniform and powers of a Nova Centurion but little instruction on how to use them. Calling himself Nova, Rider becomes a superhero, fighting costumed supervillains such as Condor, Powerhouse, Diamondhead, the Corruptor, and the Sphinx, and teaming with heroes such as Spider-Man and Thor. He initially hides his identity, but later reveals it to his family.


title: Nova (Richard Rider)

text: Rider discovers Dey's space ship orbiting Earth and uses it to journey to Xandar with Doctor Sun, Powerhouse, Comet, and Crimebuster and the Sphinx, where they join the Xandarians' war against the Skrulls. With the help of Rom the Space Knight, the Skrulls are defeated. Wanting to return to Earth, Rider is released from his duties on Xandar and relinquishes his powers.


title: Nova (Richard Rider)

text: Upon his return to Earth, Rider struggles to readjust due to his failure to complete high school. Unknown to him, the planet Xandar is utterly destroyed in an attack by the space pirate Nebula. With the help of Night Thrasher, Rider regains his powers and joins the New Warriors superhero team, where he becomes close friends with Speedball. Richard briefly dates Yale student Laura Dunham and teammate Namorita.


title: Nova (Richard Rider)

text: Rider encounters Garthan Saal, a former Nova Corps Centurion who had been driven insane by absorbing too much Nova Force, the source of power for Nova Centurions. Saal seeks more power so he can restore Xandar to its former glory. He strips Rider of his powers and transports him to Xandar. Saal is defeated. Rider witnesses the reformation of the Nova Corps and receives the rank of Centurion Prime.


title: Nova (Richard Rider)

text: Assigned to Earth, Rider is confronted with the challenge of balancing dual lives as a member of both the Nova Corps and the New Warriors. Rider encounters a Nova Corps member from an alternate timeline named Nova 0:0, who prepares him to stop the Deathstorm, which is coming to destroy Earth. Because Rider defies Xandar's Queen Adora to stop the Deathstorm, he is temporarily stripped of his powers and rank, but is given back his powers when his replacement sacrifices himself.


title: Nova (Richard Rider)

text: Nova briefly travels the US with the reformed New Warriors as part of a reality television show. Rider leaves the group when he is summoned to Xandar alongside the entire Nova Corps, which has been fully mobilized to respond to the Annihilation Wave, a force from the Negative Zone led by Annihilus. The wave decimates Xandar and the corps in a surprise attack. As the only surviving centurion, Rider makes contact with the Xandarian Worldmind, a living supercomputer that regulates the Nova Force and is caretaker of the entire database of Xandarian civilization. The Worldmind uploads itself and the entire Nova Force into Rider, greatly enhancing his abilities. During the Annihilation War, Rider takes command of the United Front, a loose collaboration of soldiers. In a nearly year-long campaign, Rider resists the Wave's advance across the galaxy until the United Front suffers a swift defeat. He leads a small team into the Wave's conquered territory and eventually engages Annihilus in personal combat, killing him.


title: Nova (Richard Rider)

text: After the Annihilation War, Rider returns to Earth to rest. However, finding out that his pleas for help in the Annihilation War were ignored by Earth's superheroes because of a Civil War, and meeting Penance - his old friend Speedball, who was mentally scarred by the events leading up to said war - Rider returns to space, feeling out of place on Earth and disturbed by what Penance had become.


title: Nova (Richard Rider)

text: Attempting to aid the Kree against an from the Phalanx, Rider is wounded and crash lands on a sparsely populated Kree outpost. While Rider's unconscious body recovers, Worldmind deputizes a local Kree commander, Ko-Rel, to guard him. Rider is infected by the transmode virus and joins the Phalanx. Now tasked with killing Rider before the Worldmind falls into enemy hands, Ko-Rel attacks him, only to be killed by Gamora in retaliation. Upon her death, her fraction of the Nova force returns to Rider and enables him to overcome the transmode virus. He flees Kree space pursued by Gamora and a Phalanx-controlled Drax. Seeking a cure for the transmode virus, Rider eventually arrives on Kvch, home planet of the Technarchy. Rider enlists the help of the mutant Warlock and his son Tyro, who cure Rider, Drax, and Gamora of the transmode virus. The five return to Hala to engage the Phalanx.


title: Nova (Richard Rider)

text: When ambushed by Skrulls during the "Secret Invasion" storyline, Rider is aided by Kl'rt. He learns about the Secret Invasion and heads for Earth. Rider learns that Project Pegasus, the base where his brother now works, is under Skrull attack. Working with Darkhawk, Rider successfully stops the Skrulls' advance. The scientists of the facility extract the Worldmind from his brain and use the supercomputer to jump-start a project known as the quantum flask, which restores Quasar to life. A Skrull warship is about to attack Project Pegasus but is destroyed by a band of alien Nova Centurions who then declare their allegiance to Rider.