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Artificial Christmas Tree
An artificial Christmas tree is an artificial pine or fir tree manufactured for the specific purpose of use as a Christmas tree. The earliest artificial Christmas trees were wooden, tree-shaped pyramids or feather trees, both developed by Germans. Most modern trees are made of polyvinyl chloride (PVC) but many other types of trees have been and are available, including aluminum Christmas trees and fiber-optic illuminated Christmas trees. History The first artificial Christmas trees were developed in Germany during the 19th century, though earlier examples exist. These "trees" were made using goose feathers that were dyed green.Forbes, Bruce David. ''Christmas: A Candid History'',Google Books, University of California Press, 2007, pp. 121–22, () The German feather trees were one response by Germans to continued deforestation in Germany. Developed in the 1880s, the feather trees became increasingly popular during the early part of the 20th century.John, J. ''A Christmas Compend ...
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Fiber-optic Christmas Tree
An optical fiber, or optical fibre in Commonwealth English, is a flexible, transparent fiber made by drawing glass (silica) or plastic to a diameter slightly thicker than that of a human hair. Optical fibers are used most often as a means to transmit light between the two ends of the fiber and find wide usage in fiber-optic communications, where they permit transmission over longer distances and at higher bandwidths (data transfer rates) than electrical cables. Fibers are used instead of metal wires because signals travel along them with less loss; in addition, fibers are immune to electromagnetic interference, a problem from which metal wires suffer. Fibers are also used for illumination and imaging, and are often wrapped in bundles so they may be used to carry light into, or images out of confined spaces, as in the case of a fiberscope. Specially designed fibers are also used for a variety of other applications, some of them being fiber optic sensors and fiber lasers. ...
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The Baltimore Sun
''The Baltimore Sun'' is the largest general-circulation daily newspaper based in the U.S. state of Maryland and provides coverage of local and regional news, events, issues, people, and industries. Founded in 1837, it is currently owned by Tribune Publishing. The ''Baltimore Sun's'' parent company, '' Tribune Publishing'', was acquired by Alden Global Capital, which operates its media properties through Digital First Media, in May 2021. History ''The Sun'' was founded on May 17, 1837, by printer/editor/publisher/owner Arunah Shepherdson Abell (often listed as "A. S. Abell") and two associates, William Moseley Swain, and Azariah H. Simmons, recently from Philadelphia, where they had started and published the '' Public Ledger'' the year before. Abell was born in Rhode Island, became a journalist with the ''Providence Patriot'' and later worked with newspapers in New York City and Boston.Van Doren, Charles and Robert McKendry, ed., ''Webster's American Biographies''. (Spring ...
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Howstuffworks
HowStuffWorks is an American commercial infotainment website founded by professor and author Marshall Brain, to provide its target audience an insight into the way many things work. The site uses various media to explain complex concepts, terminology, and mechanisms—including photographs, diagrams, videos, animations, and articles. The website was acquired by Discovery Communications in 2007 but was sold to Blucora in 2014. The site has since expanded out into podcasting, focusing on factual topics. In December 2016, HowStuffWorks, LLC became a subsidiary of OpenMail, LLC, later renamed System1. In 2018, the podcast division of the company, which had been spun-off by System1 under the name Stuff Media, was acquired by iHeartMedia for $55 million. History In 1998, North Carolina State University instructor Marshall Brain started the site as a hobby. In 1999, Brain raised venture capital and formed HowStuffWorks, Inc. In March 2002, HowStuffWorks was sold to the Convex Grou ...
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Polyethylene
Polyethylene or polythene (abbreviated PE; IUPAC name polyethene or poly(methylene)) is the most commonly produced plastic. It is a polymer, primarily used for packaging ( plastic bags, plastic films, geomembranes and containers including bottles, etc.). , over 100 million tonnes of polyethylene resins are being produced annually, accounting for 34% of the total plastics market. Many kinds of polyethylene are known, with most having the chemical formula (C2H4)''n''. PE is usually a mixture of similar polymers of ethylene, with various values of ''n''. It can be ''low-density'' or ''high-density'': low-density polyethylene is extruded using high pressure () and high temperature (), while high-density polyethylene is extruded using low pressure () and low temperature (). Polyethylene is usually thermoplastic, but it can be modified to become thermosetting instead, for example, in cross-linked polyethylene. History Polyethylene was first synthesized by the German chemis ...
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Ponderosa Pine
''Pinus ponderosa'', commonly known as the ponderosa pine, bull pine, blackjack pine, western yellow-pine, or filipinus pine is a very large pine tree species of variable habitat native to mountainous regions of western North America. It is the most widely distributed pine species in North America.Safford, H.D. 2013. Natural Range of Variation (NRV) for yellow pine and mixed conifer forests in the bioregional assessment area, including the Sierra Nevada, southern Cascades, and Modoc and Inyo National Forests. Unpublished report. USDA Forest Service, Pacific Southwest Region, Vallejo, CA/ref> ''Pinus ponderosa'' grows in various erect forms from British Columbia southward and eastward through 16 western U.S. states and has been successfully introduced in temperate regions of Europe, and in New Zealand. It was first documented in modern science in 1826 in eastern Washington near present-day Spokane (of which it is the official city tree). On that occasion, David Douglas misident ...
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Douglas Fir
The Douglas fir (''Pseudotsuga menziesii'') is an evergreen conifer species in the pine family, Pinaceae. It is native to western North America and is also known as Douglas-fir, Douglas spruce, Oregon pine, and Columbian pine. There are three varieties: coast Douglas-fir (''P. menziesii'' var. ''menziesii''), Rocky Mountain Douglas-fir (''P. menziesii'' var. ''glauca'') and Mexican Douglas-fir (''P. menziesii'' var. ''lindleyana''). Despite its common names, it is not a true fir (genus ''Abies''), spruce (genus '' Picea''), or pine (genus '' Pinus''). It is also not a hemlock; the genus name ''Pseudotsuga'' means "false hemlock". Description Douglas-firs are medium-size to extremely large evergreen trees, tall (although only ''Pseudotsuga menziesii var. menziesii'', common name coast Douglas-firs, reach heights near 100 m) and commonly reach in diameter, although trees with diameters of almost exist. The largest coast Douglas-firs regularly live over 500 years, with the ...
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MP3 Player
A portable media player (PMP) (also including the related digital audio player (DAP)) is a portable consumer electronics device capable of storing and playing digital media such as audio, images, and video files. The data is typically stored on a compact disc (CD), Digital Video Disc (DVD), Blu-ray Disc (BD), flash memory, microdrive, or hard drive; most earlier PMPs used physical media, but modern players mostly use flash memory. In contrast, analogue portable audio players play music from non-digital media that use analogue media, such as cassette tapes or vinyl records. Digital audio players (DAP) were often marketed as MP3 players even if they also supported other file formats and media types. The PMP term was introduced later for devices that had additional capabilities such as video playback. Generally speaking, they are portable, employing internal or replaceable batteries, equipped with a 3.5 mm headphone jack which can be used for headphones or to connect ...
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Canadian Standards Association
The CSA Group (formerly the Canadian Standards Association; CSA) is a standards organization which develops standards in 57 areas. CSA publishes standards in print and electronic form, and provides training and advisory services. CSA is composed of representatives from industry, government, and consumer groups. CSA began as the Canadian Engineering Standards Association (CESA) in 1919, federally chartered to create standards. During World War I, lack of interoperability between technical resources led to the formation of a standards committee. CSA is accredited by the Standards Council of Canada, a crown corporation which promotes voluntary standardization in Canada. This accreditation verifies that CSA is competent to carry out standards development and certification functions, and is based on internationally recognised criteria and procedures. The CSA registered mark shows that a product has been independently tested and certified to meet recognized standards for safety or pe ...
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Underwriters Labs
The UL enterprise is a global safety science company headquartered in Northbrook, Illinois, composed of three organizations, UL Research Institutes, UL Standards & Engagement and UL Solutions. Established in 1894, the UL enterprise was founded as the Underwriters' Electrical Bureau (a bureau of the National Board of Fire Underwriters), and was known throughout the 20th century as Underwriters Laboratories. On January 1, 2012, Underwriters Laboratories became the parent company of a for-profit company in the U.S named UL LLC, a limited liability corporation, which took over the product testing and certification business. On June 26, 2022, the companies rebranded into three distinct organizations that make up the UL enterprise. UL Solutions partners with customers and stakeholders in more than 100 countries to help solve safety, security and sustainability challenges and is also responsible for managing and issuing the highly respected portfolio of UL Marks. The company is one of ...
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Prelit Tree
A pre-lit tree is a convergent product of Christmas lights and an artificial Christmas tree. The product is an artificial fir tree that comes pre-wired and strung with lights, which cannot be removed and are usually embedded within the artificial branches. The product can be sold as a kit - the user assembles the tree and plugs it into an electrical outlet - or the dealer may assemble it before the sale. Pre-lit trees may have traditional mini bulb lights, LED lights, or fiber-optic lights. Larger trees usually contain traditional strands of bulb lights while smaller tabletop trees have fiber optic branches. Some more expensive trees come with energy-efficient LED lights. Pre-lit trees are being classified into the categories of electrical products. History The first lighted Christmas trees made use of candles. Attaching the candles was a difficult process, and proved to be a fire hazard. The tree could not be left unattended when the candles were lit. A bucket of water also ...
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A Charlie Brown Christmas
''A Charlie Brown Christmas'' is a 1965 animated television special. It is the first TV special based on the comic strip ''Peanuts'', by Charles M. Schulz. Produced by Lee Mendelson and directed by Bill Melendez, the program made its debut on CBS on December 9, 1965. In the special, Charlie Brown finds himself depressed despite the onset of the cheerful holiday season. Lucy suggests he direct a neighborhood Christmas play, but his best efforts are ignored and mocked by his peers when he chooses a real, but puny, Christmas tree as a centerpiece. After the comic strip's debut in 1950, ''Peanuts'' had become a phenomenon worldwide by the mid-1960s. The special was commissioned and sponsored by The Coca-Cola Company, and was written over a period of several weeks, and produced on a small budget in six months. In casting the characters, the producers took an unconventional route, hiring child actors. The program's soundtrack was similarly unorthodox, featuring a jazz score by pianis ...
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