nyuuzyou/wikis huggingface dataset:
Opossum

== Description ==
A New World marsupial of the family Didelphidae. The North American, or common possum (Didelphis marsupialis) has a pointy white face and coarse, straight gray fur with a long, prehensile hairless tail.
== Synonyms and Related Terms ==
oppossum (sp); possum; Didelphis marsupialis; Beutelratten Deut., Ned); zarigüeyas (Esp.); tlacuaches (Esp.); zorras mochileras (Esp.); sarigues (Fr.); dydelfowate (Pol.); gambá (Port.);
==Physical and Chemical Properties==
* Fur fiber is coarse. 
* Guard hair is dense, long, straight, and evenly distributed.
==Resources and Citations==
* Encyclopedia Britannica, http://www.britannica.com Comment: "opossum." Accessed 25 Jan. 2005 .
* Edward Reich, Carlton J. Siegler, Consumer Goods: How to Know and Use Them, American Book Company, New York City, 1937
* Wikipedia: http://en.wikipedia.org/wiki/Opossum (accessed Sept. 7, 2005)
Category:Materials database
Optical density

== Description ==
The measurement unit for opacity. Optical density is expressed as the logarithm to base 10 of the reciprocal of transmittance (transmission measurement) or reflectance (reflection measurement).
== Synonyms and Related Terms ==
Schwärzung (Deut.); densité optique (Fr.);
==Resources and Citations==
* ASTM, Standard Terminology of Microscopy, Annual Book of ASTM Standards, Section 14, General Methods and Instrumentation, ASTM, E175, 75-78, May 1982
* The American Heritage Dictionary or Encarta, via Microsoft Bookshelf 98, Microsoft Corp., 1998
Category:Materials database
Optical disk

== Description ==
A plastic or glass disk used as an optical storage medium for digital data, such as music, images, or text. An analog optical disk for video images was first developed by David Gregg in 1961 (patent date). The most common optical disk is called a compact disc (CD). CD's were first used as audio storage media that could hold up to 74 minutes of high fidelity sound. Later developments created computer readable CD's for storage of up to 680 megabytes of data, images and software. Other varieties of optical disks include early laserdiscs and the more recent digital videodiscs (DVD). 
For all optical disks, the hard thin substrate, such as polycarbonate, is coated with a reflective aluminum layer that is protected with a thin acrylic lacquer. In read only memory CD's (i.e. CD-ROM and audio CD's), the data layer is pressed into the plastic by a stamper during the injection molding process. The digital pattern is read by a laser scanning the imprinted surface then monitoring the variations in the reflected laser beam. For recordable CD's, a thin layer of a transparent organic dye covers the reflective metallic layer. The recording laser selectively melts pits in the dye to make it opaque and thus the reading laser will not be reflected back in these regions.
== Synonyms and Related Terms ==
CD-ROM; compact disc; optical disc; laserdisc; videodisc; digital versatile disc; digital videodisc; DVD; optische schijf (Ned.); disque optique (Fr.); optischer Plattenspeicher (Deut.); optische Speicherplatte (Deut.); disco a lettura ottica (It.); disco ottico (It.); disco óptico (Esp.); optisk skiva (Svend.)
==Resources and Citations==
* The American Heritage Dictionary or Encarta, via Microsoft Bookshelf 98, Microsoft Corp., 1998
* Encyclopedia Britannica, http://www.britannica.com Comment: "optical storage." Accessed 15 Mar. 2005 .
* Multilingual Glossary for Art Librarians at http://www.ifla.org/VII/s30/pub/mgl.htm
* Wikipedia: http://en.wikipedia.org/wiki/Optical_disk (Accessed Feb. 2, 2006)
Category:Materials database
Optical glass

== Description ==
A fine grade of glass used in microscopes, telescopes, binoculars, cameras, and other items requiring visual acuity. Primary patents for making optical glass were made in 1798 by P.L. Guinand, a Swiss inventor. Commercial processes for making consistent quality glass were developed in the mid 19th century when the Chance brothers in England introduced the melt-stirring process. Concurrent work in Germany by the Zeiss Company, Ernst Abbe, and Otto Schott established Jena Glass Works as a major supplier of optical glass. Optical glass is clear, flawless, and has a very controlled refractive index. Flint glass produces a higher refractive index and dispersive power while Soda-lime glass, or crown glass, produces a lower refractive index and lower dispersive power. Optical glasses are cooled slowly and sometimes annealed for months to minimize distortions. 
== Synonyms and Related Terms ==
crystal; lens; eyeglass; magnifying glass; flint glass
== Physical and Chemical Properties ==
* Insoluble in all solvents except hydrofluoric acid.
* Density (leaded-glass) = 3.86 g/ml
* Density (flint glass) = 2.9-5.9 g/ml
* Refractive index = 1.65
* Glass transition temperature = ~540 C
* Warm to touch compared to minerals
== Resources and Citations ==
* Wikipedia: Optical glass (Access Oct. 2023)
* Encyclopedia Britannica, http://www.britannica.com Comment: "industrial glass" [Accessed May 5, 2004].
* Edward Reich, Carlton J. Siegler, Consumer Goods: How to Know and Use Them, American Book Company, New York City, 1937
* Random House, Webster's Encyclopedic Unabridged Dictionary of the English Language, Grammercy Book, New York, 1997
* The American Heritage Dictionary or Encarta, via Microsoft Bookshelf 98, Microsoft Corp., 1998
Category:Materials database
Optical microscopy

== Description ==
Optical microscopy (also called light microscopy) is a technique for the visual characterization of materials. It is possible to evaluate both physical and chemical properties of materials based on light interactions with a sample while observing it at magnification. Various reagents, optical filters, and preparation methods are available that may either enhance or provide additional visual cues, facilitating characterization. The basic configuration consists of two lens systems, in which the objective lens forms a magnified image of the object, which is further magnified by the eyepieces. Transparent samples are typically viewed with transmitted light, while opaque samples are observed with reflected light. Both lighting configurations may be necessary to characterize a sample.
Broad ranges of artists' materials lend themselves to light microscopic analysis. Materials such as pigments, textile fibers, paper fibers, woods, and corrosion products are examined using high-magnification techniques that require a prepared sample. Information about gross surface features can be gleaned using low-magnification microscopes and do not require sampling the object. In the case of multilayered objects (for example an easel painting or polychrome sculpture), samples prepared as cross sections allow the analyst to address stratigraphy issues and questions about artist's technique. A cross section is an excised sample that has been mounted in a resin block, which is cut, ground, and polished perpendicular to the layering. The cross section is then viewed in reflected light. Details of the number of layers and their ordering, thickness, condition, and composition can be assessed. The analysis of cross sections is one of the more widely used optical microscopy techniques in conservation.
The description above obtained from the National Gallery of Art, Scientific Research: Glossary of Conservation Terminology
== Synonyms and related terms ==
microscope optique (Fr.)
==Resources and Citations==
* Wikipedia: Optical microscope
* Walter C. McCrone, "Polarized Light Microscopy in Conservation: A Personal Perspective" JAIC Vol 33(2):101-14, 1994.
* Olympus Microscopy Resource Center at http://www.olympusmicro.com
* ASTM, Standard Terminology of Microscopy, Annual Book of ASTM Standards, Section 14, General Methods and Instrumentation, ASTM, E175, 75-78, May 1982
Category:Materials database
Optical properties

== Description ==
A general term used to incorporate the visual descriptive properties of a material. Optical properties include birefringence, refractive index. reflectance, optical density and brightness.
==Resources and Citations==
* Hoechst Celanese Corporation, Dictionary of Fiber & Textile Technology (older version called Man-made Fiber and Textile Dictionary, 1965), Hoechst Celanese Corporation, Charlotte NC, 1990
* Random House, Webster's Encyclopedic Unabridged Dictionary of the English Language, Grammercy Book, New York, 1997
Category:Materials database
Optical rouge

== Description ==
A synthetic iron oxide abrasive that was used for polishing glass lenses (Organ, 1968). Optical rouge has been replaced by cerium oxide which polishes faster. See Ceriorouge.
== Comparisons ==
==Resources and Citations==
* R.M.Organ, Design for Scientific Conservation of Antiquities, Smithsonian Institution, Washington DC, 1968
Category:Materials database
Opticon UV-57

== Description ==
[Opticon Chemical, CA] A brand name for a single-component UV curing adhesive. Opticon UV-57 is a quick setting adhesive with a refractive index close to glass so that it forms a clear glass-to-glass bond (Madsen 1972). It sets in approximately 5 minutes at room temperature when exposed to ultraviolet light.
==Physical and Chemical Properties==
* Soluble in acetone.
* Refractive Index - 1.5316
==Resources and Citations==
* H.Madsen, "A New Product for Mending Glass" Studies in Conservation, 17:131-132, 1972.
Category:Materials database
Oranda seri/Paseri (Parsley) - left (210 L)

[[[SliderGallery rightalign|Uemura_07-23-2009_210.jpg~Normal|Uemura_07-23-2009_210_UV.jpg~UV]]]{| class="wikitable"
|-	
! scope="row"|Museum number
| 210
|-	
! scope="row"|Uemura number / title
| ; "Haze-some 25"
|-	
! scope="row"|Folder location
| 3rd shelf
|-	
! scope="row"|Sample location
| left (210 L)
|-	
! scope="row"|Fiber type
| silk
|-	
! scope="row"|Color
| light ochre
|-	
! scope="row"|Dyestuff (Japanese common name)
| おらんだせり /パセリ : Oranda seri/Paseri
|-	
! scope="row"|Dye (English common name)
| Parsley
|-	
! scope="row"|Plant part
| leaf /unspecified
|-	
! scope="row"|Dyestuff extraction
| boiled in water
|-	
! scope="row"|Auxiliary agent in dye bath
| -
|-	
! scope="row"|Mordant
| iron
|-	
! scope="row"|Other auxiliary agent
| -
|-	
! scope="row"|Uemura's notes
| Use of parsley as dyestuff was recorded in the Senryo shokubutsu fu () 1972, Japan.
|-	
! scope="row"|Uemura's date
| Kyoto
|}
Category:Uemura dye archive
Oranda seri/Paseri (Parsley) - right (210 R)

[[[SliderGallery rightalign|Uemura_07-23-2009_210.jpg~Normal|Uemura_07-23-2009_210_UV.jpg~UV]]]{| class="wikitable"
|-	
! scope="row"|Museum number
| 210
|-	
! scope="row"|Uemura number / title
| ; "Haze-some 25"
|-	
! scope="row"|Folder location
| 3rd shelf
|-	
! scope="row"|Sample location
| right (210 R)
|-	
! scope="row"|Fiber type
| silk
|-	
! scope="row"|Color
| light yellowish cream
|-	
! scope="row"|Dyestuff (Japanese common name)
| おらんだせり /パセリ : Oranda seri/Paseri
|-	
! scope="row"|Dye (English common name)
| Parsley
|-	
! scope="row"|Plant part
| leaf /unspecified
|-	
! scope="row"|Dyestuff extraction
| boiled in water
|-	
! scope="row"|Auxiliary agent in dye bath
| -
|-	
! scope="row"|Mordant
| alum
|-	
! scope="row"|Other auxiliary agent
| -
|-	
! scope="row"|Uemura's notes
| Use of parsley as dyestuff was recorded in the Senryo shokubutsu fu () 1972, Japan.
|-	
! scope="row"|Uemura's date
| Kyoto
|}
Category:Uemura dye archive
Orange

== Description ==
One of the basic colours of the visible light spectrum. Orange corresponds to the wavelength range 570 -630 nm.
See: Colour
== Synonyms and related terms ==
orange (Dan., Fr., Sven.); Orange (Deut.); naranja (Esp.); arancione (It.); oranje (Ned.); oranże (Pol.); laranja (Port.)
Category:Materials database
Orange mineral

== Description ==
A bright orange pigment composed of lead tetroxide. Orange mineral is synthetically made by calcining lead white or heating red lead oxide to a higher temperature. Although orange mineral has the same chemical composition as red lead oxide, it has a different crystalline structure. Orange mineral is not sufficiently lightfast for use as an artist pigment. It is used in industrial paints, primers and printing inks.
== Synonyms and Related Terms ==
laranja mineral (Port.); orange lead
==Physical and Chemical Properties==
* Toxic by inhalation or ingestion. 
* Skin contact may cause irritation or ulcers. 
* Carcinogen, teratogen, suspected mutagen.
==Physical and Chemical Properties==
Soluble in glacial acetic acid, hot HCl, nitric acid with peroxide present. Insoluble in water and ethanol.
Composition	Pb3O4
Density 	9.0 g/ml
==Resources and Citations==
* R. J. Gettens, G.L. Stout, Painting Materials, A Short Encyclopaedia, Dover Publications, New York, 1966
* G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p.445
* Ralph Mayer, A Dictionary of Art Terms and Techniques, Harper and Row Publishers, New York, 1969 (also 1945 printing)
* Richard S. Lewis, Hawley's Condensed Chemical Dictionary, Van Nostrand Reinhold, New York, 10th ed., 1993
* Dictionary of Building Preservation, Ward Bucher, ed., John Wiley & Sons, Inc., New York City, 1996
Category:Materials database
Orange peel

== Description ==
A surface texture term indicating a rough, pebbled surface that resembles an orange skin. Orange peel is a defect that usually occurs on paints and varnishes when an outer skin forms before the inner portion of the coating has dried.
==Resources and Citations==
* Ralph Mayer, A Dictionary of Art Terms and Techniques, Harper and Row Publishers, New York, 1969 (also 1945 printing)
* Richard S. Lewis, Hawley's Condensed Chemical Dictionary, Van Nostrand Reinhold, New York, 10th ed., 1993
* Dictionary of Building Preservation, Ward Bucher, ed., John Wiley & Sons, Inc., New York City, 1996
* The Dictionary of Paper, American Paper Institute, New York, Fourth Edition, 1980
Category:Materials database
Orange pigments

== Description ==
Orange is a color produced by light having a spectrum dominated by energy with a wavelength of about 590–630nm. It is considered a secondary color in the traditional RYB color wheel made by mixing red and yellow. An average orange color is represented by the following color coordinates: 
* Hex triplet: # FF7F00 
* RGB: (255, 127, 0); CMYK (0, 0, 0, 100) 
* HSV: (30°, 100%, 100%)
Examples of inorganic orange pigments:
* oxides (Mars orange, mineral orange)
* chromates (lead chromate)
* sulfides (realgar, antimony orange)
* other (cadmium orange, molybdate orange)
Examples of organic orange pigments:
* plant (saffron, annatto)
* synthetic (Hansa, naphthol orange, methyl orange)
== Synonyms and Related Terms ==
Orange (Deut.); naranje (Esp.); anaranjados (Esp.); orange (Dan., Fr., Sven.); arancione (It.); subruber (Lat.); laranja (Port.); oranje (Ned.); pigmentos-laranja (Port.)
Category:Materials database
Orange shellac

== Description ==
Light orange, transparent flakes of shellac that have been cleaned but not bleached. Orange shellac has also been made by coloring bleached shellac with up to 1% orpiment.
== Synonyms and Related Terms ==
gomme laque orangée (Fr.); goma laca anaranjada (Esp.) 
[[[SliderGallery rightalign|MFA- Shellac, orange.jpg~FTIR]]]
==Physical and Chemical Properties==
Soluble in ethanol.
==Resources and Citations==
* G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p. 706
* Dictionary of Building Preservation, Ward Bucher, ed., John Wiley & Sons, Inc., New York City, 1996
* Art and Architecture Thesaurus Online, https://www.getty.edu/research/tools/vocabulary/aat/, J. Paul Getty Trust, Los Angeles, 2000
Category:Materials database
Orange vermilion

== Description ==
Vermilion with a orange shade (Mayer 1969).
== Synonyms and Related Terms ==
bermellón anaranjado (Esp.)
==Resources and Citations==
* Ralph Mayer, A Dictionary of Art Terms and Techniques, Harper and Row Publishers, New York, 1969 (also 1945 printing)
* Art and Architecture Thesaurus Online, http://www.getty.edu/research/tools/vocabulary/aat/, J. Paul Getty Trust, Los Angeles, 2000
Category:Materials database
Orasol dyes

== Description ==
[Ciba-Geigy] A registered trademark for a series of solvent soluble dyes. Orasol® dyes are transparent, have good tinting strength and are lightfast. They are used in resin, wax, shellac, and epoxy coatings. Orasol® dyes are also used in inks, paints, wood stains, fibers and plastics.
== Synonyms and Related Terms ==
Orasol dye
== Physical and Chemical Properties ==
Soluble in alcohols and ketones. Insoluble in hydrocarbon solvents.
== Resources and Citations ==
Ciba Geigy Specialty Chemicals: Orasol dyes information
* Richard S. Lewis, Hawley's Condensed Chemical Dictionary, Van Nostrand Reinhold, New York, 10th ed., 1993
* Gordon Hanlon, contributed information, 1998
* Conservation Support Systems, Catalog, 1997
Category:Materials database
Orcein

== Description ==
The chemical name for the red dyes extracted from several lichens of the genera Evernia, Roccella, Ramalina and Lecanoria, such as Evernia prunastri, Roccella phycopsis and Ramalina scopulorum. 
== Synonyms and Related Terms ==
CI Natural Red 28; archil; orchil; lacmus;
== Risks ==
* ThermoFisher: SDS
== Physical and Chemical Properties ==
Orcein is soluble in ethanol. It is an indicator dye that turns blue in alkaline solutions.
CAS	1400-62-3
Category:Materials database
Orchid juice

== Description ==
A gel-like mucilage extracted from the bulb of orchid plants, such as Sobralia citrina. Orchid juice was used as an adhesive in Mexico after the Spanish conquest of 1519.
== Synonyms and Related Terms ==
Sobralia citrina; orchid mucilage; orchid glue; orchid sap
==Resources and Citations==
* The Dictionary of Art, Grove's Dictionaries Inc., New York, 1996 Comment: "Adhesive"
Category:Materials database
Ore

== Description ==
A naturally occurring mineral or mixture of minerals that is mined as a resource. Ores are processed to extract metals and other valuable constituents. Native, or metallic ores, contain metals in their pure state. Gold, silver, platinum and copper have been found as native ores. Oxide ore is a groups of metallic elements combined with oxygen to form oxide, carbonate or silicate minerals. Metals combined with sulfate anions are called sulfate ores.
== Synonyms and Related Terms ==
mena (Esp.); minerai (Fr.); minério (Port.); Erz (Deut.); erts (Ned.)
Category:Materials database
Organdy

== Description ==
A thin, stiff, semitransparent fabric. Organdy is a plain woven cloth made from cotton then sized with shellac, gum or a synthetic resin. The sizing gives organdy its crisp, transparent appearance that is launder resistant. Organdy is used for blouses, dresses, trim and curtains.
== Synonyms and Related Terms ==
organdie; organdí (Esp.)
== Additional Images ==
File:Organdy dress MFA.jpg|Organdy dressMFA# 2011.463
File:Image3_802582.jpg|Organdy apronMFA #: 51.1357
File:Organdy cap MFA.jpg|Organdy capMFA# 55.604
File:Image3_802539.jpg|Organdy
Category:Materials database
Organic acid

== Description ==
A broad class of non-mineral acids that include formic, acetic, lactic, oxalic, citric, stearic, and tannic acids. Organic acids occur naturally in plants, fruits, animals, and microorganisms. They are much weaker proton donors than mineral acids, but can still have detrimental effects on materials, such as paper, leather, metals, and photographs. Of concern in a museum environment is the volatility of many of organic acids and their ubiquitous presence in many materials.
== Synonyms and Related Terms ==
carboxylic acid
==Resources and Citations==
* P.Hatchfield, Pollutants in the Museum Environment, Archetype Press, London, 2002.
* R. J. Gettens, G.L. Stout, Painting Materials, A Short Encyclopaedia, Dover Publications, New York, 1966
* G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p. 313
* Richard S. Lewis, Hawley's Condensed Chemical Dictionary, Van Nostrand Reinhold, New York, 10th ed., 1993
* Matt Roberts, Don Etherington, Bookbinding and the Conservation of Books: a Dictionary of Descriptive Terminology, U.S. Government Printing Office, Washington DC, 1982
* Random House, Webster's Encyclopedic Unabridged Dictionary of the English Language, Grammercy Book, New York, 1997
Category:Materials database
Organochlorine

== Description ==
A class of organic compounds that contain chlorine. In general, many chlorine compounds are toxic and carcinogenic. The term 'organochlorine' is also used to refer specifically to chlorinate hydrocarbon insecticides. As insecticides, organochlorine compounds are divided into bioaccumulative (DDT and dieldrin) and nonaccumulative (lindane, chlordane). Many of these compounds have been banned or their use is restricted.
Category:Materials database
Organometallic compound

== Description ==
A class of substances in which the molecules contain at least one metal-to-carbon bond. Organometallic compounds containing lead, tin, zinc, and mercury are used commercially. For example, organotin compounds, are used as herbicides, pesticides, stabilizers for polyvinyl chloride, and flame retardants. Mercurials, such as methylmercury and phenylmercuric chloride, caused severe environmental problems after they were used as herbicides. Diethylzinc has been used in the vapor-phase to neutralize acids and deposit an alkaline reserve in archival materials. Tetraethyl lead was once used as an antiknock agent in gasoline but is now restricted since combustion releases lead particulates into the atmosphere.
== Synonyms and Related Terms ==
organo-metallic; metallo-organic; organometalloid; composé organométallique (Fr.)
==Resources and Citations==
* Encyclopedia Britannica, http://www.britannica.com Comment: "organometallic compound" [Accessed April 1, 2003].
* Art and Architecture Thesaurus Online, https://www.getty.edu/research/tools/vocabulary/aat/, J. Paul Getty Trust, Los Angeles, 2000
Category:Materials database
Organophosphates

== Description ==
A class of organic compounds that contain phosphorus Organophosphates are esters of phosphinic acid. They are used as plasticizers, flame retardants and insecticides. The term 'organophosphate' is commonly used to refer to the insecticide materials. As insecticides, organophosphate compounds act as cholinesterase inhibitors. Examples are diazinon, dichlorvos, malathion, and chlorpyrifos. All organophosphates should be handled with care as they tend to have toxic effects on the nervous system.
== Synonyms and Related Terms ==
organophosphorus; diazinon; dichlorvos; malathion; chlorpyrifos
Category:Materials database
Organosilicon

== Description ==
Any of several silicone polymers which have a silicone-carbon bond. Organosilicon compounds were first made by Friedel in 1863. Since silicon is quadrivalent like carbon, it has a very similar chemistry. The silicon-carbon bond is almost as strong as a carbon-carbon bond. See also silicone.
== Synonyms and Related Terms ==
organosilane; organosiliceo (Esp.); organosilano (It.); organosilano (Port.)
Category:Materials database
Organosol

== Description ==
A colloidal dispersion in an organic solvent. An organosol usually contains a suspension of a finely divided particles of an insoluble resin. When the solvent evaporates, the resin solidifies as a hardened plastic. Organosols are used to mold polyvinyl chloride resins. A plastisol is a specific type or organosol where the resin is suspended in a plasticizer.
== Synonyms and Related Terms ==
plastisol
Category:Materials database
Organotin

== Description ==
Organometallic compounds containing a tin-carbon bond. Organotin compounds are used as pesticides, fungicides, flame retardants, and stabilizers. Examples include dibutyl tin oxide, dibutyltin dilaurate, tri-n-butyl tin oxide and tri-n-butyl tin naphthenate.
Organotin is on the ILFI Red list of building materials.
== Synonyms and Related Terms ==
dibutyl tin oxide; tri-n-butyl tin oxide; tri-n-butyl tin naphthenate
==Resources and Citations==
* G.Caneva, M.P.Nugari, O.Salvadori, Biology in the Conservation of Works of Art, ICCROM, Rome, 1991
Category:Materials database