nyuuzyou/wikis huggingface dataset:
Resorcinol formaldehyde resin

== Description ==
Resorcinol reacts with formaldehyde to form polymers. Resorcinol formaldehyde resins cure at room temperature. They form a very strong bond that is resistant to moisture, acids and weathering. Resorcinol resins are used as adhesives for wood veneers, plywoods, and for rubber-textile laminates.
== Synonyms and Related Terms ==
resorcinol-formaldehyde resin; resina resorcinol-formaldehído (Esp.); resina de resorcinol-formaldeído (Port.)
== Risks ==
Skin contact can cause irritation.
==Physical and Chemical Properties==
Soluble in water, ketones and alcohols prior to curing.
==Resources and Citations==
* G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p. 667
* Michael McCann, Artist Beware, Watson-Guptill Publications, New York City, 1979
* Pam Hatchfield, Pollutants in the Museum Environment, Archetype Press, London, 2002
* Van Nostrand's Scientific Encyclopedia, Douglas M. Considine (ed.), Van Nostrand Reinhold, New York, 1976
* The Merck Index, Martha Windholz (ed.), Merck Research Labs, Rahway NJ, 10th edition, 1983 Comment: entry 8323
Category:Materials database
Respirator

== Description ==
A device are worn over the nose and mouth to minimize inhalation of dust and fumes. There are three basic types of respirators:
1. Air-Supplying - These respirators supply fresh air or oxygen by means of a gas cylinders or air compressor. They are complex and expensive systems that are usually only used in oxygen-deprived atmospheres.
2. Air-Purifying - These respirators use filters or chemical cartridges to purify ambient air as it is inhaled. They can be as simple as a dust mask or as complex as a full-face mask with multiple cartridges. Different cartridges and filters are designed to trap specific gases, vapors and dusts, such as solvents, silica or lead.
3. Powered Air- Purifying - These respirators pump ambient air through filters or cartridges then supply it to the interior of a full face mask. These respirators are often used when normal air-purifying respirator do not fit properly.
== Synonyms and Related Terms ==
inhalator
==Resources and Citations==
* M. Rossol, The Artist's Complete Health and Safety Guide, Allworth Press: New York, 1994.
Category:Materials database
Restauro

= Restauro =
An information resource for restorers, curators and monument conservators. Restauro provides access to numerous print publications (in German and English) such as books, articles and the magazine 'Restauro'. It also contains links to discussion groups and international conservation organizations.
Web Address 	http://www.restauro.de/frames.htm
Information Online	Publishes newsletter
Publishes journal
Books / brochures / articles
Publications viewable online
Related links
Searchable 	Yes
Categories 	General
Website Languages 	German
== Comments ==
Beyond this, Restauro sees itself as an interdiscplinary platform for all those involved in the preservation of art and objects of cultural value.
Category:Directory
Category:Directory: General
Restoration

== Description ==
Definition: All actions directly applied to a single and stable item aimed at facilitating its appreciation, understanding and use. These actions are only carried out when the item has lost part of its significance or function through past alteration or deterioration. They are based on respect for the original material. Most often such actions modify the appearance of the item. Examples of restoration are retouching a painting, reassembling a broken sculpture, reshaping a basket, filling losses on a glass vessel. 
(ref. ICOM-CC document 'Terminology to characterize the conservation of tangible cultural heritage', prepared for ICOM-CC meeting in New Delhi, 2008).
Category:Materials database
Retardant

== Description ==
1) A chemical used to slow the drying rate of paint. Retardants were commonly used in the nineteenth century for wet-in-wet techniques. Examples of retardants for linseed oil paints are clove oil, spike oil, lavender oil, rosemary oil, and poppy seed oil. Butyl lactate has been used as a retardant for industrial lacquers. 
2) A chemical added to a dye bath to slow the rate of dyeing.
== Synonyms and Related Terms ==
inhibitor; retarder (Br.)
==Resources and Citations==
* Reed Kay, The Painter's Guide To Studio Methods and Materials, Prentice-Hall, Inc., Englewood Cliffs, NJ, 1983
* Ralph Mayer, A Dictionary of Art Terms and Techniques, Harper and Row Publishers, New York, 1969 (also 1945 printing)
* Hoechst Celanese Corporation, Dictionary of Fiber & Textile Technology (older version called Man-made Fiber and Textile Dictionary, 1965), Hoechst Celanese Corporation, Charlotte NC, 1990
* Art and Architecture Thesaurus Online, https://www.getty.edu/research/tools/vocabulary/aat/, J. Paul Getty Trust, Los Angeles, 2000
Category:Materials database
Retardation

== Description ==
In optics, the lag distance of two refracted rays when they emerge from a crystal. The retardation is due to the refractive index of the crystal and its thickness.
== Synonyms and Related Terms ==
retard (Fr.); Verlangsamung (Deut.)
==Resources and Citations==
* Walter C. McCrone, John Gustave Delly, The Particle Atlas, W. McCrone Associates, Chicago, IV, 1972
Category:Materials database
Reticulin

== Description ==
A protein in connective tissue. Reticulin occurs with collagen and elastin. It is found in hides and skin, especially between the grain layer and the flesh. Reticulin is composed of about 85% protein, 4.2 % carbohydrate and 11% fat. Its protein content is similar to collagen except that it does not contain any hydroxyproline.
==Physical and Chemical Properties==
Insoluble in boiling water
Category:Materials database
Reused wool

== Description ==
The supply of raw wool each year in insufficient to meet the world demand. Thus some wool that has previously been made into yarns or fabrics is reused. The waster fabrics or yarns are sorted, oiled then teased into fibers. Recovered wool is classified as (Cook 1984): 
* shoddy: wool recovered from unfelted fabrics such as tweeds, knits and worsteds. 
* mungo: wool recovered from felted fabrics such as velours or melton. 
* extract: wool recovered from wool blend fabrics. 
Reused wool fibers are inferior to new, or fleece, fibers. Recovered fibers are often mixed with fleece fibers for low to medium quality fabrics. Fabrics that contain no reused wool will be marked as virgin wool.
== Synonyms and Related Terms ==
used wool; recovered wool; shoddy; mungo; extract wool; lana reutilizada (Esp.)
==Resources and Citations==
* Rosalie Rosso King, Textile Identification, Conservation, and Preservation, Noyes Publications, Park Ridge, NJ, 1985
* J.Gordon Cook, Handbook of Textile Fibres:I Natural Fibres, Merrow Publishing Co. , Durham, England, 1984
Category:Materials database
Reverse calf

== Description ==
A leather prepared from calfskin finished on the flesh side. Reverse calf is stuffed with oils to increase water-resistance, then buff to a suede-like finish. It was originally called trench calf in England, then later termed hunting calf because of its use for hunting clothing. In the late 18th and early 19th centuries, reverse calf was used for ledger covers (Roberts and Eddington 1982).
== Synonyms and Related Terms ==
rough calf; reveresed calf; trench calf; hunting calf; ternero afelpado (Esp.); mouton retourné (Fr.)
==Resources and Citations==
* Matt Roberts, Don Etherington, Bookbinding and the Conservation of Books: a Dictionary of Descriptive Terminology, U.S. Government Printing Office, Washington DC, 1982
* Edward Reich, Carlton J. Siegler, Consumer Goods: How to Know and Use Them, American Book Company, New York City, 1937
Category:Materials database
Rhamnetin

== Description ==
A yellow to green organic colorant extract from small berries from any shrub of the buckthorn family, such as Rhamnus infectorius, R. amygdalinus, R.oleodies, or R.alaternus. Rhamnetin is a water-soluble colorant composed of the methyl ester of a tri-hydroxyflavonol. It was extracted from the berries for use in textiles, wood stains, and lake pigments. The unripe berries produce a yellow juice used to make sap green lake. The ripe berries were used to make Dutch pink, a yellow lake.
== Physical and Chemical Properties ==
Soluble in hot water, methanol, acetone.
Composition 	C16H12O7
Molecular Weight	mol. wt. = 316.27
Category:Materials database
Rhamnose

== Description ==
White crystalline solid with a very sweet taste. Rhamnose is a natural sugar that is found in poison sumac.
== Synonyms and Related Terms ==
6-deoxy-l-mannose; l-mannomethylose; isodulcit
==Physical and Chemical Properties==
Slightly soluble in water.
Composition 	C6H12O5
CAS 	3615-41-6
Melting Point 	82-92 C
Molecular Weight	mol.wt.= 164.16
Category:Materials database
Rhapid gel

== Description ==
[Art Preservation Services, NY] A brand name for high performing humidity buffering gel. RHapid Gel contain silica gel enclosed in packets made from a nonwoven polyolefin fabric. The covering allows moisture vapor passage in both directions. RHapid Gel packets preconditioned to a set humidity (0% 40% 45% 50% 60% for use 0-65% range) to provide a stable moisture content in a closed environment. RHapid Gel packets have an average value of MH* is 5 for a range of 20% to 60% relative humidity.
== Synonyms and Related Terms ==
RHapid gel; RHapid gel; RHapid Pak
==Resources and Citations==
* Art Preservation Services, NY: Website 
* S. Weintraub 'Demystifying Silica Gel' Link
Category:Materials databaseCategory: MWGCategory: Climate/Environment
Rhenium

== Description ==
A hard, silvery-white naturally occurring rare-earth metallic element. Rhenium was first isolated in 1925 by Noddack and Tacke using an x-ray spectrograph. It has an average concentration of 0.001 ppm in the earth's crust and is obtained from rare-earth minerals such as gadolinite, molybdenite and columbite. Rhenium is used in platinum, tungsten, and molybdenum alloys for electronic filaments and thermocouples. It is also used for plating jewelry and medical instruments as well as for backing mirrors.
== Synonyms and Related Terms ==
Re; rhénium (Fr.); renio (It., Esp.); Rênio (Port.)
== Risks ==
* Powder is flammable 
* Fisher Scientific: MSDS
==Physical and Chemical Properties==
Reacts with oxidizing mineral acids. Insoluble in hydrochloric and hydrofluoric acids
Composition 	Re (atomic no. 75)
CAS 	7440-15-5
Mohs Hardness 	7.0
Melting Point 	3180 C
Density 	21.02 g/ml
Molecular Weight	atomic wt = 186.207
Boiling Point 	5630 C
==Resources and Citations==
* Web Elements: Website
* G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p. 668
* Richard S. Lewis, Hawley's Condensed Chemical Dictionary, Van Nostrand Reinhold, New York, 10th ed., 1993
* Random House, Webster's Encyclopedic Unabridged Dictionary of the English Language, Grammercy Book, New York, 1997
* The Merck Index, Martha Windholz (ed.), Merck Research Labs, Rahway NJ, 10th edition, 1983 Comment: entry 8343
* The American Heritage Dictionary or Encarta, via Microsoft Bookshelf 98, Microsoft Corp., 1998
Category:Materials database
Rheology

== Description ==
The study of the deformation and viscosity of materials in terms of stress, strain and time. A rheometer is the instrument used to measure the viscosity and elasticity of resin solutions. 
== Synonyms and Related Terms ==
rheometer; rhéologie (Fr.); Rheologie (Deut.)
==Resources and Citations==
* Wikipedia: Rheology
* National Gallery of Art, Scientific Research: Glossary of Conservation Terminology
Category:Materials database
Rheostat

== Description ==
An adjustable resistor used to regulate current. Rheostats can be metallic, carbon or electrolytic systems. The metallic rheostat uses a metal wire or ribbon and a sliding contact such that the length of the wire from switch to contact increases as the dial is turned. This increases the resistance and decreases the current output. Rheostats were first used for light dimmer switches in Chicago's F.G. Robie house designed by Frank Lloyd Wright in 1909.
== Synonyms and Related Terms ==
rhéostat (Fr.); reóstato (Port.);
Category:Materials database
Rhinestone

== Description ==
An inexpensive, imitation gemstone that simulates the appearance of a diamond, but is much softer. Rhinestones originally were made from rock crystal (transparent quartz) found in or near the Rhine River. They were cut and polished to simulate diamonds. In 1775, a French jeweler, George Stass, began coating the bottom of the rock crystals to increase their reflectivity. The Aurora Borealis diamond was introduced in 1955 in which a coating was applied to the surface of the rock crystals to produce interference colors. This coating was later applied to rhinestones made of acrylic plastic. Paste diamonds, made from highly refractive glass, are also called rhinestones. Paste diamonds lack the double refraction and regular molecular arrangement of true gemstones.
== Synonyms and Related Terms ==
rock crystal; paste diamond; Cornish diamond; strass; costume diamonds; Aurora Borealis
== Comparisons ==
==Resources and Citations==
* G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p. 364
* Encyclopedia Britannica, http://www.britannica.com Comment: "rhinestone." Acccessed 14 Sept. 2005 .
* Wikipedia: http://en.wikipedia.org/wiki/Rhinestone (Accessed Sept. 14, 2005)
* 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
Rhinoceros

== Description ==
A member of any of the species of odd-toed ungulates in the family Rhinocerotidae. Rhinoceroses are some of the largest remaining megafauna with adults weighing at least one ton. They have a herbivorous diet, small brains, one or two horns, and a thick (1.5–5 cm), protective skin formed from layers of collagen positioned in a lattice structure. Rhinoceros are killed by poachers for their horns, which are bought and sold on the black market for high prices, leading to most living rhinoceros species being considered endangered. Rhinoceros horns are a solid mass of matted hair.
== Synonyms and Related Terms ==
rhinoceros horn
== Additional Images ==
File:Afr.white.Rhino_Forestry.images.jpg|thumb|African white rhinoceros Ceratotherium simum
File:Afr.Blk.Rhino_Forestry.images.jpg|African black rhinoceros Diceros bicornis
==Resources and Citations==
* Wikipedia: Rhinocerous Access August 2022
Category:Materials database
Rhodamine 6G

== Description ==
A strong, bright red fluorescent dye that was developed in 1892 by Bernthsen. Rhodamine 6G is the ethyl ester of diethyldiamino-o-carboxy-phenyl-xanthenyl chloride. It is used as a dye (textiles, paper) and as a lake pigment (inks, oil paints, plastics).
== Synonyms and Related Terms ==
CI 45160; Basic Red 1; Pigment Red 81 (phosphotungstomolybdic acid salt)
== Risks ==
* ThermoFisher: SDS
==Physical and Chemical Properties==
Composition 	C26H26N2O3Cl
CAS 	12224-98-5
Molecular Weight	mol. wt. = 479.02
==Resources and Citations==
* R. J. Gettens, G.L. Stout, Painting Materials, A Short Encyclopaedia, Dover Publications, New York, 1966
* Richard S. Lewis, Hawley's Condensed Chemical Dictionary, Van Nostrand Reinhold, New York, 10th ed., 1993
* The Merck Index, Martha Windholz (ed.), Merck Research Labs, Rahway NJ, 10th edition, 1983 Comment: entry 8349
* Colour Index International online at www.colour-index.org
Category:Materials database
Rhodamine B

== Description ==
A strong, bright red fluorescent dye. Rhodamine B is a basic dye that was developed in 1887 by Ceresole. It is used as textile and paper dye, as a pigment, and as a staining reagent for the detection of fats and oils. Some oil modified materials such as alkyds and urethanes will also stain with rhodamine (Wolbers et al 1990). Rhodamine B has been used as a fluorescent colorant in inks (ballpoint, printing), wood stains, distemper paints, and shoe polish.
== Synonyms and Related Terms ==
Basic Violet 10; CI 45170; tetraethylrhodamine; D&C Red No. 19, Solvent Red 49; Pigment Violet 1 (phosphotungstomolybdic acid salt); Pigment Red 169 (copper ferrocyanide salt); Pigment Red 173 (aluminum salt); Rhodamine (Deut.); Rodamina B (Esp.); rodamina B (Port.); rhodamine B (Fr.)
[[[SliderGallery rightalign|PV001 sun rhodamine b 221-0035.TIF~FTIR 221-0035(MFA)|PV1 rhodamine b (magruder mm0107-dc).TIF~FTIR mm0107-dc(MFA)|Pv1 rhodamine B (magruder mm0122-dc).TIF~FTIR mm0122-dc(MFA)|Pv1 rhodamine B (magruder mm1219-dc).TIF~FTIR mm1219-dc(MFA)|Rhodamine (Forbes MFA 44) copy.tif~Raman (MFA)|f44sem.jpg~SEM|f44edsbw.jpg~EDS|rhodamine b.jpg~Chemical structure]]]
== Comparisons ==
Pigment number	Manufacture	Pigment name	Manufacture CI number	Comments
PV001 	Sun 	rhodamine B 	221-0035 	
PV001 	Magruder 	rhodamine B 	mm0107-dc 	
PV001 	Magruder 	rhodamine B 	mm0122-dc 	
PV001 	Magruder 	rhodamine B 	mm1219-dc 	
== Risks ==
* Carcinogen. 
* Mutagen. 
* ThermoFisher: SDS
==Physical and Chemical Properties==
* Green crystals or violet powder. 
* Soluble in water, ethanol, polar solvents. 
* Maximum absorption wavelength = 545 nm. 
* Maximum emission wavelength = 625 nm.
Composition 	C28H31ClN2O3
CAS 	81-88-9
Melting Point 	210-211 C
Molecular Weight	mol. wt. = 478.68
==Resources and Citations==
* R. Wolbers, N. Sterman and C. Stavroudis, "Notes for Workshop on New Methods in the Cleaning of Paintings", 1990, GCI, Los Angeles. 
* Website for absorption/fluorescent spectra: http://www.omlc.ogi.edu/spectra/PhotochemCAD/html/rhodamineB.html
* Reed Kay, The Painter's Guide To Studio Methods and Materials, Prentice-Hall, Inc., Englewood Cliffs, NJ, 1983
* Richard S. Lewis, Hawley's Condensed Chemical Dictionary, Van Nostrand Reinhold, New York, 10th ed., 1993
* Richard C. Wolbers, Nanette T. Sterman, Chris Stavroudis, Notes for Workshop on New Methods in the Cleaning of Paintings, J.Paul Getty Trust, Los Angeles, 1990
* Monona Rossol, The Artist's Complete Health and Safety Guide, Allworth Press, New York, 1994
* The Merck Index, Martha Windholz (ed.), Merck Research Labs, Rahway NJ, 10th edition, 1983 Comment: entry 8349
* Dye History: www.straw.com/sig/dyehist - discovered 1887
* Aldrich Chemical Catalog Comment: p. 1299
* Colour Index International online at www.colour-index.org
Category:Materials database
Rhodamine toner

[[[SliderGallery rightalign|f44sem.jpg~SEM|f44edsbw.jpg~EDS]]]
== Description ==
Red to violet colored lakes from any of several synthetic red rhodamine dyes. These fluorescent dyes are precipitated with phosphotungstic or phosphomolybdic acid. Rhodamine toners have good lightfastness. They are used in printing inks.
==Resources and Citations==
* Richard S. Lewis, Hawley's Condensed Chemical Dictionary, Van Nostrand Reinhold, New York, 10th ed., 1993
* 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
Rhodium

== Description ==
A white, naturally occurring metallic element. Rhodium was discovered by William Wollaston in 1803. It is a very rare element belonging to the platinum group. Rhodium has an estimated concentration of 0.01 ppm in the earth's crust. It is extracted from platinum ores such as rhodite, sperrylite, and iridosmine. Metallic rhodium is used as an alloy with platinum. It is used as a nontarnishing plating finish for silverware and jewelry. Rhodium is also used for high-reflectivity mirror-surfaces on searchlights, optical instruments, and cinema projectors.
== Synonyms and Related Terms ==
Rh; rodio (It., Esp.); Ródio (Port.)
== Risks ==
* Powder is flammable. 
* Echemi: SDS
==Physical and Chemical Properties==
Soluble in fused potassium bisulfate. Insoluble in acids and aqua regia. 
Face-centered cubic crystal.
Composition 	Rh (atomic no. 45)
CAS 	7440-16-6
Mohs Hardness 	6.0
Melting Point 	1966 C
Density 	12.41 g/ml
Molecular Weight	atomic wt = 102.91
Boiling Point 	3600-3825 C
==Resources and Citations==
* G.S.Brady, Materials Handbook, McGraw-Hill Book Co., New York, 1971 Comment: p.668
* Richard S. Lewis, Hawley's Condensed Chemical Dictionary, Van Nostrand Reinhold, New York, 10th ed., 1993
* Van Nostrand's Scientific Encyclopedia, Douglas M. Considine (ed.), Van Nostrand Reinhold, New York, 1976
* Random House, Webster's Encyclopedic Unabridged Dictionary of the English Language, Grammercy Book, New York, 1997
* The Merck Index, Martha Windholz (ed.), Merck Research Labs, Rahway NJ, 10th edition, 1983 Comment: entry 8353
* The American Heritage Dictionary or Encarta, via Microsoft Bookshelf 98, Microsoft Corp., 1998
* Web Elements at http://www.webelements.com/webelements/elements/text/Rh/key.html gives discovery by William Hyde Wollaston, England, 1803
* Chemical & Engineering News, American Chemical Society, Washington DC, 81 (36) , Sept. 8, 2003 Comment: Jack Halpern, p. 114: discovered in 1803 by English chemist William H. Wollaston
Category:Materials database
Rhodochrosite

== Description ==
A rose red mineral composed of manganese carbonate. Rhodochrosite is mined in Rumania (Kapnik), Germany (Saxony, Westphalia), England (Cornwall) as well as in the U.S. (New Jersey, Connecticut, Colorado, Montana, and Nevada). The transparent to opaque mineral ranges in color from pink to deep red. It has been used as a minor ornamental stone and as a source for manganese.
== Synonyms and Related Terms ==
manganese carbonate; dialogite; manganese spar; Rhodochrosit (Deut.); Manganspat (Deut.); Himbeerspat (Deut.); rodocrosita (Esp.); rodocrosite (Port.); rodochrosiet (Ned.).)
== Risks ==
Toxic by inhalation. 
[[[SliderGallery rightalign|Rhodochrosite IR-ATR RRUFF R040133.png~IR-ATR (RRUFF)|Rhodochrosite Raman RRUFF R040133.png~Raman (RRUFF)|rhodochrositeRS.jpg~Raman (RASMIN)]]]
==Physical and Chemical Properties==
* Trigonal crystal; rhombohedral faces
* Cleavage perfect in three directions 
* Fracture = uneven to granular
* Luster = vitreous to pearly
* Streak = white
* Fluorescence = inert to dull red in LW; inert to pink in SW
* Pleochroism = moderate to strong
Composition 	MnCO3
Mohs Hardness 	3.5 - 4.5
Density 	3.7 g/ml (but may be lower)
Refractive index	1.597 to 1.817
Birefringence 	0.218 - 0.220
==Resources and Citations==
* Gem Identification Lab Manual, Gemological Institute of America, 2016.
* Mineralogy Database: Rhodochrosite
* Frank A. Lent, Trade names and Descriptions of Marbles, Limestones, Sandstones, Granites and Other Building Stones Quarried in the United States Canada and other Countries., Stone Publishing Co, New York, 1925
* C.W.Chesterman, K.E.Lowe, Audubon Society Field Guide to North American Rocks and Minerals, Alfred A. Knopf, New York, 1979
* Wikipedia: Rhodochrosite (Accessed Sept. 14, 2005 and Dec 2022)
* Van Nostrand's Scientific Encyclopedia, Douglas M. Considine (ed.), Van Nostrand Reinhold, New York, 1976
* 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
Rhodolite

== Description ==
A pink to light violet variety of the mineral pyrope in the garnet group. Rhodolite has been used as a gemstone.
== Synonyms and Related Terms ==
garnet; rodolita (Esp.); rhodolite (Fr.); Rhodolit (Deut.); rhodoliet (Ned.)
==Resources and Citations==
* 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