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Christmas Lighting Technology
Holiday lighting technology has been subject to considerable development and variation since the replacement of candles by electric lights. While originally used during the Christmas holidays as Christmas lights, modern electric light arrays have become popular around the world in many cultures and are used both during religious festivals and for other purposes unconnected to any festivities. Incandescent lights Incandescent light bulbs have been commonly used in holiday lights until recently. These lights produce a broad-spectrum white light, and are colored by coating the glass envelope with a translucent paint which acts as a color filter. Some early Japanese-made lamps used colored glass. Glow discharge lights Glow discharge light bulbs also can be used as holiday lights. The most common are neon, argon and mercury fluorescent lamps. They can glow in different colors, depending of the gas filling or the chemical composition of the phosphor. Neon lamps have a characteristic ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Christmas
Christmas is an annual festival commemorating the birth of Jesus Christ, observed primarily on December 25 as a religious and cultural celebration among billions of people around the world. A feast central to the Christian liturgical year, it is preceded by the season of Advent or the Nativity Fast and initiates the season of Christmastide, which historically in the West lasts twelve days and culminates on Twelfth Night. Christmas Day is a public holiday in many countries, is celebrated religiously by a majority of Christians, as well as culturally by many non-Christians, and forms an integral part of the holiday season organized around it. The traditional Christmas narrative recounted in the New Testament, known as the Nativity of Jesus, says that Jesus was born in Bethlehem, in accordance with messianic prophecies. When Joseph and Mary arrived in the city, the inn had no room and so they were offered a stable where the Christ Child was soon born, with angels procla ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Galvanic Cell
A galvanic cell or voltaic cell, named after the scientists Luigi Galvani and Alessandro Volta, respectively, is an electrochemical cell in which an electric current is generated from spontaneous Oxidation-Reduction reactions. A common apparatus generally consists of two different metals, each immersed in separate beakers containing their respective metal ions in solution that are connected by a salt bridge or separated by a porous membrane. Volta was the inventor of the voltaic pile, the first electrical battery. In common usage, the word "battery" has come to include a single galvanic cell, but a battery properly consists of multiple cells. History In 1780, Luigi Galvani discovered that when two different metals (e.g., copper and zinc) are in contact and then both are touched at the same time to two different parts of a muscle of a frog leg, to close the circuit, the frog's leg contracts. He called this " animal electricity". The frog's leg, as well as being a detector of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Laser Lighting Display
A laser lighting display or laser light show involves the use of laser light to entertain an audience. A laser light show may consist only of projected laser beams set to music, or may accompany another form of entertainment, typically musical performances. Laser light is useful in entertainment because the coherent nature of laser light allows a narrow beam to be produced, which allows the use of optical scanning to draw patterns or images on walls, ceilings or other surfaces including theatrical smoke and fog without refocusing for the differences in distance, as is common with video projection. This inherently more focused beam is also extremely visible, and is often used as an effect. Sometimes the beams are "bounced" to different positions with mirrors to create laser sculptures. Function Scanning Laser scanners reflect the laser beam on small mirrors which are mounted on galvanometers to which a control voltage is applied. The beam is deflected a certain amou ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Bubble Light
A bubble light is a decorative device consisting of a liquid-filled vial that is heated and illuminated by an incandescent light bulb. Because of the liquid's low boiling point, 39.6°C (103.3°F), the modest heat generated by the lamp causes the liquid to boil and bubble up from the vial's base thus creating a decorative effect. Process The liquid is almost always methylene chloride, a solvent that is toxic and possibly carcinogenic. It is generally sealed in a glass vial or capsule to prevent its release; if it is broken, the area should be evacuated until the fumes have dissipated. Some early bubble lights instead used a lightweight oil or camphor (a white substance used in some moth balls) to create the low boiling point. In these older lamps, one can often see a white piece floating at the top of the vial, until the heat of the lamp dissolves it and it starts to bubble. The light from the lamp illuminates the bubbles from underneath, causing them to shine. Bubble lights of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Christmas Tree
A Christmas tree is a decorated tree, usually an evergreen conifer, such as a spruce, pine or fir, or an artificial tree of similar appearance, associated with the celebration of Christmas. The custom was further developed in early modern Germany where German Protestant Christians brought decorated trees into their homes. It acquired popularity beyond the Lutheran areas of Germany and the Baltic governorates during the second half of the 19th century, at first among the upper classes. The tree was traditionally decorated with "roses made of colored paper, apples, wafers, tinsel, nd sweetmeats". Moravian Christians began to illuminate Christmas trees with candles, which were often replaced by Christmas lights after the advent of electrification. Today, there is a wide variety of traditional and modern ornaments, such as garlands, baubles, tinsel, and candy canes. An angel or star might be placed at the top of the tree to represent the Angel Gabriel or the Star of ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fiber Optic
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. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Squirrel
Squirrels are members of the family Sciuridae, a family that includes small or medium-size rodents. The squirrel family includes tree squirrels, ground squirrels (including chipmunks and prairie dogs, among others), and flying squirrels. Squirrels are indigenous to the Americas, Eurasia, and Africa, and were introduced by humans to Australia. The earliest known fossilized squirrels date from the Eocene epoch, and among other living rodent families, the squirrels are most closely related to the mountain beaver and to the dormice. Etymology The word ''squirrel'', first attested in 1327, comes from the Anglo-Norman which is from the Old French , the reflex of a Latin word , which was taken from the Ancient Greek word (; from ) 'shadow-tailed', referring to the long bushy tail which many of its members have. The native Old English word for the squirrel, , survived only into Middle English (as ) before being replaced. The Old English word is of Common Germanic origin, c ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pumpkin
A pumpkin is a vernacular term for mature winter squash of species and varieties in the genus ''Cucurbita'' that has culinary and cultural significance but no agreed upon botanical or scientific meaning. The term ''pumpkin'' is sometimes used interchangeably with "squash" or "winter squash", and is commonly used for cultivars of '' Cucurbita argyrosperma'', '' Cucurbita ficifolia'', ''Cucurbita maxima'', '' Cucurbita moschata'', and '' Cucurbita pepo''. Native to North America (northeastern Mexico and the southern United States), ''C. pepo'' pumpkins are one of the oldest domesticated plants, having been used as early as 7,000 to 5,500 BC. Today, pumpkins of varied species are widely grown for food, as well as for aesthetic and recreational purposes. The pumpkin's thick shell contains edible seeds and pulp. Pumpkin pie, for instance, is a traditional part of Thanksgiving meals in Canada and the United States, and pumpkins are frequently carved as jack-o'-lanterns for decorat ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Snowflake
A snowflake is a single ice crystal that has achieved a sufficient size, and may have amalgamated with others, which falls through the Earth's atmosphere as snow.Knight, C.; Knight, N. (1973). Snow crystals. Scientific American, vol. 228, no. 1, pp. 100–107.Hobbs, P.V. 1974. Ice Physics. Oxford: Clarendon Press. Each flake nucleates around a dust particle in supersaturated air masses by attracting supercooled cloud water droplets, which freeze and accrete in crystal form. Complex shapes emerge as the flake moves through differing temperature and humidity zones in the atmosphere, such that individual snowflakes differ in detail from one another, but may be categorized in eight broad classifications and at least 80 individual variants. The main constituent shapes for ice crystals, from which combinations may occur, are needle, column, plate, and rime. Snow appears white in color despite being made of clear ice. This is due to diffuse reflection of the whole spectrum of light by ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Cone (geometry)
A cone is a three-dimensional geometric shape that tapers smoothly from a flat base (frequently, though not necessarily, circular) to a point called the apex or vertex. A cone is formed by a set of line segments, half-lines, or lines connecting a common point, the apex, to all of the points on a base that is in a plane that does not contain the apex. Depending on the author, the base may be restricted to be a circle, any one-dimensional quadratic form in the plane, any closed one-dimensional figure, or any of the above plus all the enclosed points. If the enclosed points are included in the base, the cone is a solid object; otherwise it is a two-dimensional object in three-dimensional space. In the case of a solid object, the boundary formed by these lines or partial lines is called the ''lateral surface''; if the lateral surface is unbounded, it is a conical surface. In the case of line segments, the cone does not extend beyond the base, while in the case of half- ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluorescence
Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation. It is a form of luminescence. In most cases, the emitted light has a longer wavelength, and therefore a lower photon energy, than the absorbed radiation. A perceptible example of fluorescence occurs when the absorbed radiation is in the ultraviolet region of the electromagnetic spectrum (invisible to the human eye), while the emitted light is in the visible spectrum, visible region; this gives the fluorescent substance a distinct color that can only be seen when the substance has been exposed to blacklight, UV light. Fluorescent materials cease to glow nearly immediately when the radiation source stops, unlike phosphorescence, phosphorescent materials, which continue to emit light for some time after. Fluorescence has many practical applications, including mineralogy, gemology, medicine, chemical sensors (fluorescence spectroscopy), fluorescent labelling, dyes, bio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Raspberry
The raspberry is the edible fruit of a multitude of plant species in the genus ''Rubus'' of the rose family, most of which are in the subgenus '' Idaeobatus''. The name also applies to these plants themselves. Raspberries are perennial with woody stems. World production of raspberries in 2020 was 895,771 tonnes, led by Russia with 20% of the total. Description A raspberry is an aggregate fruit, developing from the numerous distinct carpels of a single flower. What distinguishes the raspberry from its blackberry relatives is whether or not the torus ( receptacle or stem) "picks with" (i.e., stays with) the fruit. When picking a blackberry fruit, the torus stays with the fruit. With a raspberry, the torus remains on the plant, leaving a hollow core in the raspberry fruit. Raspberries are grown for the fresh fruit market and for commercial processing into individually quick frozen (IQF) fruit, purée, juice, or as dried fruit used in a variety of grocery products such as ras ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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