wiktionary opacity opaque Opacity may refer to Opacity optics , the degree to which light is not allowed to travel through Opaque context , a term to describe the linguistic context of co referential terms Phonological opacity , a term in phonology Opaque travel inventory , the market of selling unsold travel inventory at a discounted price Computer science How much an image will obscure the background when painted, usually defined by its alpha channel The use of an opaque data type , a data type that is incompletely described in a module interface Said of data that can only be interpreted and by an external entity, such as a magic cookie Opaque Binary Blob , a term used in Network Engineering and Computer Science disambig de Opak io Opaka nl Opaciteit doorverwijspagina simple Opacity sk Opak wuu Opacity ... more details
Refimprove date February 2010 Opacity is the measure of impenetrability to electromagnetic radiation electromagnetic or other kinds of radiation , especially visible light . In radiative transfer , it describes the absorption and scattering of radiation in a transmission medium medium , such as a plasma physics plasma , dielectric , radiation shield shielding material , glass, etc. An opaque object is neither Transparency optics transparent allowing all light to pass through nor translucent allowing .... Opacity depends on the frequency of the light being considered. For instance, some kinds .... More extreme frequency dependence is visible in the absorption line s of cold gas es. Opacity can be quantified in many ways for example, see the article mathematical descriptions of opacity . For general ... to opacity. Quantitative definition See also Extinction astronomy attenuation coefficient The words opacity and opaque are often used as colloquial terms for objects or media with the properties described above. However, there is also a specific, quantitative definition of opacity , used in astronomy, plasma physics, and other fields, given here. In this use, opacity is another term for the mass ... with frequency math nu math travels through a medium with opacity math kappa nu math and mass density ... intensity of light, at math x 0 math For a given medium at a given frequency, the opacity has a numerical ... opacity It is customary to define the average opacity, calculated using a certain weighting scheme. Planck opacity uses normalized Planck s law of black body radiation Planck black body radiation .... Rosseland opacity , on the other hand, uses a temperature derivative of Planck s law of black body ... mean free path is math lambda nu kappa nu rho 1 math . The Rosseland opacity is derived in the diffusion ... thermal equilibrium. In practice, the mean opacity for Thomson scattering Thomson electron scattering ... Mathematical descriptions of opacity Molar absorptivity Reflection physics Scattering theory References ... more details
linguistics Phonological opacity was first defined by Kiparsky ref cite book last Kiparsky first Paul editor first Osamu editor last Fujimura title Three Dimensions of Linguistic Theory publisher Tokyo Institute for Advanced Studies of Language year 1973 pages 57 86 chapter Abstractness, opacity and global rules Part 2 of Phonological representations ref as a measure of how far the context or the consequences of a Phonological rule phonological process may be determined only by examining the Transformational grammar surface structure . It was by Kiparsky defined in the following way. A phonological rule P give by math A rightarrow B C underline quad D math is opaque if any of the following surface structures exists instance of A in the math C underline quad D math environment instance of B created by P in an environment other than math C underline quad D math instance of B not derived from P that occur in the context math C underline quad D math . References Reflist Category Phonology ... more details
Technical date September 2010 Kramers opacity law describes the behavior of the opacity optics opacity in terms of the ambient density and temperature when the opacity is dominated by ionization bound free absorption the ionization of a bound electron or free free absorption also called bremsstrahlung . ref Phillips 1999 , p. 92. ref It is named after the Dutch people Dutch physicist Hendrik Kramers , who first derived the form in 1923. ref name Carroll274 Carroll 1996 , p. 274. ref The general functional form of the opacity law is math bar kappa kappa 0 rho T 7 2 , math where math bar kappa math is the average opacity, math kappa 0 math is a parameter that encapsulates fractional abundances and quantum mechanical corrections, math rho math is the density, and math T math is the temperature. This form alone is useful for understanding how changes in either the density or temperature will affect the opacity, which in turn is important in understanding radiative transfer , particularly in stellar atmosphere s. ref Carroll 1996 , p. 274 276. ref The specific forms for bound free and free free are Bound free math bar kappa 4.34 times 10 25 frac g bf t Z 1 X rho T 7 2 rm cm 2 g 1 , math Free free math bar kappa 3.68 times 10 22 g ff 1 Z 1 X rho T 7 2 rm cm 2 g 1 . math Here, math g bf math and math g ff math are the Gaunt factor s associated with bound free and free free transitions, respectively, and are quantum mechanical correction terms. The math t math is an additional correction factor, typically having a value between 1 and 100. math Z math is the fractional abundance by mass of elements heavier than hydrogen , and math X math is the fractional abundance by mass of hydrogen. ref name Carroll274 References Reflist Bibliography Cite book author Carroll, Bradley Ostlie, Dale year 1996 title Modern Astrophysics publisher Addison Wesley location url http books.google.com ... Wiley url http books.google.com books?id 4CZpQgAACAAJ DEFAULTSORT Kramers Opacity Law Category Scattering ... more details
Pfam box Symbol Opacity Name Opacity family porin protein image PDB 1p4t EBI.jpg width caption Structure of Neisserial surface protein A NspA . ref name pmid12716881 cite journal author Vandeputte Rutten L, Bos MP, Tommassen J, Gros P title Crystal structure of Neisserial surface protein A NspA , a conserved outer membrane protein with vaccine potential journal J. Biol. Chem. volume 278 issue 27 pages 24825 30 year 2003 month July pmid 12716881 doi 10.1074 jbc.M302803200 url ref Pfam PF02462 InterPro IPR003394 SMART Prosite SCOP 1p4t TCDB OPM family 26 OPM protein 1p4t PDB PDB3 1p4t A 52 174 Opacity family porins are a family of porin protein porin s from pathogenic Neisseria . These bacteria possess a repertoire of phase variable opacity proteins that mediate various pathogen host cell interactions. ref name PUB00009510 cite journal author Meyer TF, Dehio C, Gray owen SD title The role of neisserial Opa proteins in interactions with host cells journal Trends Microbiol. volume 6 issue 12 pages 489 495 year 1998 pmid 10036728 doi 10.1016 S0966 842X 98 01365 1 ref These proteins are related to OmpA like transmembrane domain family. References reflist Category Protein domains Category Protein families Category Outer membrane proteins membrane protein stub ... more details
When an electromagnetic wave travels through a medium in which it gets absorbed this is called an opacity optics opaque or attenuation constant attenuating medium , it undergoes exponential decay as described by the Beer Lambert law . However, there are many possible ways to characterize the wave and how quickly it is absorbed. This article describes the mathematical relationships among Absorption coefficient , Penetration depth and Skin depth , Propagation constant , attenuation constant , phase constant , and complex wavenumber , Refractive index Complex refractive index and refractive index Dispersion and absorption extinction coefficient , Dielectric constant Complex dielectric constant , Alternating current AC Electrical conductivity conductivity . Note that in many of these cases there are multiple, conflicting definitions and conventions in common use. This article is not necessarily comprehensive or universal. Background Unattenuated wave main Electromagnetic wave equation A electromagnetic wave propagating in the z direction is conventionally described by the equation math mathbf E z,t mathrm Re mathbf E 0 e i k z omega t math where E sub 0 sub is a vector in the x y plane, with the units of an electric field the vector is in general a complex vector , to allow for all possible polarizations and phases , math omega math is the angular frequency of the wave, k is the angular wavenumber of the wave, Re indicates real part . e is e mathematical constant Euler s number see the article Complex exponential for information about how e is raised to complex exponents. The wavelength is, by definition, math lambda frac 2 pi k math . For a given frequency, the wavelength of an electromagnetic wave is affected by the material in which it is propagating. The vacuum wavelength the wavelength that a wave of this frequency would have if it were propagating in vacuum is math lambda ... called opacity see opacity optics . Penetration depth, skin depth main Penetration depth Skin ... more details
unreferenced date January 2011 Drawdown cards are used for testing paint s and coating s through wet film preparation. Black and white cards are used to measure both Opacity optics opacity and contrast ratio . By measuring reflectance values of both parts of the card one can gain a quantitative opacity value of a paint sample. See also Glossmeter Spectrometer Category Painting materials Category Measuring instruments ... more details
Summary Created by The Neokid. Font is Ruach LET , font colour is 006600, shadow colour is FF0000. Shadow offset 7, opacity 65 , softness 4 and angle 315 degrees. Licensing GFDL self with disclaimers migration relicense ... more details
Summary Modification of Image Blue Puzzle Marble in stand.png moved shadow to its own layer, made it darker, and adjusted its opacity. Authors Nohat, NASA, Silversmith, The Transhumanist. Licensing GFDL migration relicense ... more details
Summary Information Description Created for Wikipedia SVG Help Result of creating an SVG containing black circle with a std. dev of 55.952079 rastering using inkscape, and then doing the same in RSVG, then dividing the two values together i forgot which was divided by which. Note that it is not uniform. Something is afoot Source self made with inkscape version Inkscape 0.45.1 Mar 21 2007 , rsvg version 2.16.1, division in gimp version 2.4.4 Date Location Author User User A1 User A1 User talk User A1 talk other versions SVG snippet used to generate nowiki path sodipodi type arc style opacity 1 fill 000000 fill opacity 1 fill rule evenodd stroke d7d7d7 stroke width 0.80000001 stroke linecap round stroke linejoin round stroke miterlimit 4 stroke dasharray none stroke dashoffset 0 stroke opacity 1 filter url filter3409 id path2330 sodipodi cx 285.71429 sodipodi cy 352.36218 sodipodi rx 99.999992 sodipodi ry 99.999992 d M 385.71429 352.36218 A 99.999992 99.999992 0 1 1 185.7143,352.36218 A 99.999992 99.999992 0 1 1 385.71429 352.36218 z nowiki Licensing PD self date April 2008 ... more details
The Sharp Scale was devised by Henrietta Sharp Cockrell as an objective and scientific way to measure the Opacity optics opacity translucency of paper, particularly of manuscript folios, in the field without specialized equipment, for example in a museum or library setting. The folio is held at a distance of 15 cm. from a constant 60 watt light source such as an unshaded table lamp . A dowel or pencil is held behind and against it, creating a silhouette. Folios are added until the outline of the pencil is no longer visible. The number of the folios needed to obscure the silhouette of the pencil is recorded. ref Savage Smith, 2005, p. ??? ref Notes Reflist References Savage Smith, Emilie 2005 , A descriptive catalogue of Oriental manuscripts at St John s College, Oxford , Oxford Oxford University Press. International Standard Book Number ISBN Special BookSources 0199201951 0 19 920195 1 External links http www.ncbi.nlm.nih.gov pmc articles PMC1894869 Book Review Category Units of measure Category Book arts Category Papermaking ... more details
Unreferenced stub auto yes date December 2009 The radio window is the range of frequencies of electromagnetic radiation that the earth s atmosphere lets through. The wavelength s in the radio window run from about one centimeter to about eleven meter waves. File Atmospheric electromagnetic opacity.svg thumb center 600px Opacity of the Earth s atmosphere See also Astronomical window Infrared window Optical window Radio propagation Radio astronomy DEFAULTSORT Radio Window Category Electromagnetic spectrum Physics stub pl Okno radiowe ... more details
orphan date September 2009 Glaukomflecken simply means glaucoma flecks. ref Dr Khairul Nazri Mohammad Articles Author , Waterford General Hospital, IRELAND ref It is anterior subcapsular or capsular opacity associated with focal epithelial infarct from past Angle acute angle closure glaucoma. ref Kanski JJ Clinical Ophthalmology 5th ed ref Other name include Cataracta Disseminata subepithilias or Glaukomatosa Acuta . ref Ocular Pathology. Glaukomflecken March 2008 ref Aetiology Lens Epithelial necrosis due to high pressure within the anterior chamber pushing against the iris overlying the lens epithelium resulting mechanical damage or accumulation of toxin within the epithelium which resulted in epithelial necrosis and therefore anterior lens opacity. ref Eu Eong KG et al. Int Ophthalmol. 1993 17 127 9. ref Symptoms and sign The lens anatomy lens opacity can be visualized with a slit lamp and since the opacity occurs usually within the visual axis or pupillary aperture, visual impairment is a possibility. Since glaucomflecken is associated with acute angle closure glaucoma, sign for the latter can be present such as shallow anterior chamber, closed angle, hypermetropia etc. ref Dr Khairul Nazri Mohammad, Waterford General Hospital, IRELAND ref Case Example and Image http www.sarawakeyecare.com Atlasofophthalmology glaucoma Glaucomatpicture1.htm Glaucomflecken in primary acute angle closure glaucoma . ref Photo by Dr. Ngo Chek Tung, Universiti Malaysia Sarawak UNIMAS , Kuching, Sarawak, East Malaysia ref References references Category Medical signs ... more details
Summary A simulation of how Global s logo will be displayed if it is a US program and US bug is present. The logo s size, opacity isn t necessarily right. br NOTE every Global stations except Global Ontario would display their local name too for example, Global Edmonton, something like this http a123.g.akamai.net f 123 41524 1d www.globaltv.com globaltv edmonton images asphaltjungle.jpg Licensing self author User Zzyzx11 Zzyzx11 , the author of this derivative work GFDL migration review Global logo PD textlogo Trademark ... more details
transparent opacity 0.75 filter alpha opacity 75 zoom 1 Havana , Cuba November 1953 Ministry of Auditing ... 1em background transparent opacity 0.75 filter alpha opacity 75 zoom 1 Brussels , Belgium September ... transparent opacity 0.75 filter alpha opacity 75 zoom 1 Rio de Janeiro , Brazil May 1959 Tribunal ... transparent opacity 0.75 filter alpha opacity 75 zoom 1 Vienna Austria May 1962 Court of Audit of the Republic ... opacity 0.75 filter alpha opacity 75 zoom 1 Jerusalem , Isra l June 1965 State Comptroller ... height 1em background transparent opacity 0.75 filter alpha opacity 75 zoom 1 Tokyo , Japan May 1968 ... height 1em background transparent opacity 0.75 filter alpha opacity 75 zoom 1 Montreal September 1971 ... 1em background transparent opacity 0.75 filter alpha opacity 75 zoom 1 Madrid May 1974 Tribunal de Cuentas div IX div style margin left 1em font size .9em line height 1em background transparent opacity 0.75 filter alpha opacity 75 zoom 1 Lima October 1977 Contralor a General de la Rep blica del Per div X div style margin left 1em font size .9em line height 1em background transparent opacity 0.75 filter alpha opacity 75 zoom 1 Nairobi , Kenya June 1980 Office of the Comptroller and Auditor General ... opacity 0.75 filter alpha opacity 75 zoom 1 Manilla , Philippines April 1983 Philippine Commission on Audit div XII div style margin left 1em font size .9em line height 1em background transparent opacity 0.75 filter alpha opacity 75 zoom 1 Sydney April 1986 Australian National Audit Office div XIII div style margin left 1em font size .9em line height 1em background transparent opacity 0.75 filter alpha opacity 75 zoom 1 Berlin , Germany June 1989 Bundesrechnungshof div File Stamps of Germany ... 1em font size .9em line height 1em background transparent opacity 0.75 filter alpha opacity 75 zoom ... div style margin left 1em font size .9em line height 1em background transparent opacity 0.75 filter alpha opacity 75 zoom 1 Cairo Egypt September October 1995 Central Auditing Organization Central Auditing ... more details
of treating opacity To fully model the photosphere one would need to include every absorption line ..., and also all spectra are not fully known. Therefore one needs to simplify the treatment of opacity. Methods used in photospheric models include Opacity sampling OS Opacity sampling means that the radiative ... of the spectrum. Although the model would improve with more frequencies included, opacity sampling uses as few as practical, to still get a realistic model, thereby minimizing calculation time. Opacity distribution functions ODF In using opacity distribution functions, the spectra are divided into subsections ... function. Similar to the opacity sampling method, this is improved by adding more intervals but at the cost ... as well as those using opacity sampling or opacity distribution functions. MARCS The MARCS Model Atmospheres ... has since involved better modeling of the line opacityopacity sampling instead of opacity ... more details
Unreferenced date October 2008 Opalescence is a type of dichroism seen in highly colloid dispersed systems with little Opacity optics opacity . The material appears yellowish red in transmitted light and blue in the scattered light perpendicular to the transmitted light. The phenomenon is named after the appearance of opal s. There are different degrees of opalescent behaviour. One can still see through a slightly opalescent phase. The more particles and the bigger the particles are, the stronger the scattering arising from them and the cloudier the particular phase will look. At a certain concentration the scattering is so strong that all light passing through is scattered, so that it is not transparent any more. Examples are the Diffuse sky radiation blue sky in the daytime and the yellowish red sky at sunset. Another example can be made by adding a few droplets of milk to a glass of water. The liquid appears bluish but if one looks through the glass at a light source, it becomes yellowish red. Opalescence is an effect exploited in lustreware pottery. Category Optical phenomena wiktionary optics stub de Opaleszenz es Opalescencia fr Opalescence nl Opalescentie ja pl Opalescencja pt Opalesc ncia ru sv Opalescens uk ... more details
otheruses Bort or boart is a term used in the diamond industry to refer to shards of Gemstone gem grade quality diamonds. In the manufacturing and heavy industries, bort is used to describe dark, imperfectly formed crystallized diamonds of varying levels of opacity. The lowest grade, crushing bort , is crushed by steel mortar and pestle mortar s and used to make industrial grade abrasive grits. Small bort crystals are used in drill bit s. The Democratic Republic of the Congo provides 75 of the world supply of crushing bort. References http www.idai.org idaibulletin edited diamonds.htm accessed 20 Mar 2005 Category Diamond mineral stub lv Borts miner ls pl Bort ru uk ... more details
Extinction coefficient refers to several different measures of the absorption of light in a medium In chemistry, the mass attenuation coefficient mass extinction coefficient also called mass attenuation coefficient or mass absorption coefficient and the molar absorptivity molar extinction coefficient are parameters defining how strongly a substance absorbs light at a given wavelength, per Mole unit mass unit or per molar concentration , respectively. In physics, the extinction coefficient is the imaginary part of the complex index of refraction , which also relates to light absorption. For the quantitative relationship between the chemistry and physics definitions, see Mathematical descriptions of opacity . disambig es Coeficiente de extinci n fr Absorptivit molaire de Extinktionskoeffizient ... more details
Cataract may refer to Cataract , an opacity in the lens of the eye Cataract band , a European metalcore band from Switzerland signed to Metal Blade Records Cataract, a large, powerful waterfall The Shawinigan Cataractes , a QMJHL team Cataract, a song by Sparta from their 2002 album Wiretap Scars Cataracts , a song by Andrew Bird on his 2007 album Armchair Apocrypha Cataracts of the Nile Cataract, Wisconsin , an unincorporated community in the United States The Old Cataract Hotel, a famous hotel in Aswan, Egypt which is mentioned the mystery Death on the Nile disambig cs Katarakt da Katarakt de Katarakt nl Cataract no Katarakt pl Katarakta sv Katarakt ... more details
Wiktionary legibility Legibility is the degree at which glyph s individual characters in penmanship , typesetting , calligraphy , etc. are understandable or recognizable based on appearance. Legibility is determined by a glyph s stroke width, angle, style, x height, slant, color, opacity, and other intrinsic attributes of the individual glyphs. Distinguished from readability which refers to entire words, sentences, and paragraphs. Readability is determined by line length, primary and secondary leading, justification, typestyle, kerning, tracking, point size, etc. In practical application some attributes cross over and affect both. Category Writing de Leserlichkeit pt Legibilidade ... more details
Summary I took the public domain image of the Last Supper Image Leonardo da Vinci 1452 1519 The Last Supper 1495 1498 .jpg thumb and used GIMP to create a mirror image, copy the original and the mirror to two layers of a new image, superimposed them by altering their opacity and then exported the resulting image as a PNG. This should more or less recreate the image that Slavisa Pesci made. http edition.cnn.com 2007 WORLD europe 07 27 davinci.codes.reut I adjusted the image to line the two Jesuses up with each other, as in Pesci s image. Troy34 Licensing self GFDL cc by sa 2.5,2.0,1.0 migration relicense ... more details
Summary Information Description Gosset 4 21 polytope graph, Coxeter plane projection Vertices colored by multiplicty red 1, orange 8, yellow 24. There is VAST edge overlaps 6720 total edges , using partial opacity, makes inner lines darker. Source I User Tomruen Tom Ruen User talk Tomruen talk created this work entirely by myself. Date 04 43, 19 February 2010 UTC Author User Tomruen Tom Ruen User talk Tomruen talk other versions Licensing PD self date February 2010 ... more details
The mechanism is the driving mechanism behind the changes in luminosity of many types of pulsating variable stars. Here, the Greek letter kappa is used to indicate the radiative opacity at any particular depth of the stellar atmosphere. In a normal star, an increase in compression of the atmosphere causes an increase in temperature and density this produces a decrease in the opacity of the atmosphere, allowing heat energy to escape more rapidly. The result is an equilibrium condition where temperature and pressure are maintain in a balance. However, in cases where the opacity increases with temperature, the atmosphere becomes unstable against pulsations. ref name maeder2009 If a layer of a stellar atmosphere moves inward, it becomes denser and more opaque, causing heat flow to be checked. In return, this heat increase causes a build up of pressure that pushes the layer back out again. The result is a cyclic process as the layer repeatedly moves inward and then is forced back out again. ref name de boer seggewiss2008 Stellar non adiabatic pulsation resulting from the mechanism occurs in regions where hydrogen and helium are partly ionized, or where there are negative hydrogen ions. An example of such a zone is in RR Lyrae variable s where the partial second ionization of helium occurs. ref name maeder2009 Hydrogen ionization is most likely the cause of pulsation activity in Mira variable s, Ap and Bp star rotating Ap stars and Pulsating white dwarf ZZ Ceti variables . In Beta Cephei variable s, stellar pulsations occur at a depth where the temperature reaches approximately 200,000 K and there is an abundance of iron. The increase in the opacity of iron at this depth is known as the Z bump, where Z is the astronomical symbol for elements other than hydrogen and helium. ref name leblanc2010 References reflist refs ref name de boer seggewiss2008 cite book author de Boer, Klaas Sjoerds Seggewiss, Wilhelm title Stars and stellar evolution page 172 publisher L E ... more details
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