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Carcel
The Carcel is a former French unit for measuring the intensity of light. The unit was defined in 1860 as the intensity of a Carcel lamp with standard burner and chimney dimensions, which burnt colza oil (obtained from the seed of the plant Brassica campestris) at a rate of 42 grams of colza oil per hour with a flame 40 millimeters in height. In modern terminology one carcel equals about 9.74 candelas. References See also *Jail A prison, also known as a jail, gaol (dated, standard English, Australian, and historically in Canada), penitentiary (American English and Canadian English), detention center (or detention centre outside the US), correction center, correc ..., or cárcel in Spanish Physical quantities Units of luminous intensity Lighting Obsolete units of measurement {{Measurement-stub ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Carcel Lamp
The Carcel lamp was an efficient lighting device used in the nineteenth century for domestic purposes and in France as the standard measure for illumination. The lamp was invented by the French watchmaker Bernard Guillaume Carcel (1750–1818) to overcome the disadvantages of the Argand-type lamps then in use. The vegetable - mostly colza - oils then available were thick and would not travel far up a wick. The Argand lamps used a gravity feed which meant that the oil reservoir was located above the burner, casting a shadow and making the lamp top heavy. Carcel designed a lamp with the oil reservoir under the burner, in the body of the lamp. To keep the oil moving up to the burner, Carcel housed a clockwork mechanism in the lamp base that drove a small pump submerged in the oil tank. The winding key was located at the bottom of the lamp base. Another innovative feature was that fuel was pumped into the wick tubes at a greater volume than was necessary for burning so that it overfl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Colza Oil
Close-up of canola blooms Canola flower Rapeseed oil is one of the oldest known vegetable oils. There are both edible and industrial forms produced from rapeseed, the seed of several cultivars of the plant family Brassicaceae. Historically, it was eaten in limited quantities due to high levels of erucic acid, which is damaging to the cardiac muscle of animals and imparts a bitter taste, and glucosinolates, which made it less nutritious in animal feed. Rapeseed oil can contain up to 54% erucic acid. Canola oil is a food-grade version derived from rapeseed cultivars bred for low erucic acid content. Also known as low erucic acid rapeseed (LEAR) oil, it has been generally recognized as safe by the United States Food and Drug Administration. Canola oil is limited by government regulation to a maximum of 2% erucic acid by weight in the US and the EU, with special regulations for infant food. These low levels of erucic acid do not cause harm in humans. In commerce, non-food variet ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Illuminance
In photometry, illuminance is the total luminous flux incident on a surface, per unit area. It is a measure of how much the incident light illuminates the surface, wavelength-weighted by the luminosity function to correlate with human brightness perception.International Electrotechnical Commission (IEC): ''International Electrotechnical Vocabulary.'ref. 845-21-060, illuminance/ref> Similarly, luminous emittance is the luminous flux per unit area emitted from a surface. Luminous emittance is also known as luminous exitance. In SI units illuminance is measured in lux (lx), or equivalently in lumens per square metre ( lm· m−2). Luminous exitance is measured in lm·m−2 only, not lux. International Electrotechnical Commission (IEC): ''International Electrotechnical Vocabulary.'ref. 845-21-081, luminous exitance/ref> In the CGS system, the unit of illuminance is the phot, which is equal to . The foot-candle is a non-metric unit of illuminance that is used in photography. Ill ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Candelas
The candela ( or ; symbol: cd) is the unit of luminous intensity in the International System of Units (SI). It measures luminous power per unit solid angle emitted by a light source in a particular direction. Luminous intensity is analogous to radiant intensity, but instead of simply adding up the contributions of every wavelength of light in the source's spectrum, the contribution of each wavelength is weighted by the standard luminosity function (a model of the sensitivity of the human eye to different wavelengths). A common wax candle emits light with a luminous intensity of roughly one candela. If emission in some directions is blocked by an opaque barrier, the emission would still be approximately one candela in the directions that are not obscured. The word ''candela'' is Latin for ''candle''. The old name "candle" is still sometimes used, as in ''foot-candle'' and the modern definition of ''candlepower''. Definition The 26th General Conference on Weights and Measures (CG ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Jail
A prison, also known as a jail, gaol (dated, standard English, Australian, and historically in Canada), penitentiary (American English and Canadian English), detention center (or detention centre outside the US), correction center, correctional facility, lock-up, hoosegow or remand center, is a facility in which inmates (or prisoners) are confined against their will and usually denied a variety of freedoms under the authority of the state as punishment for various crimes. Prisons are most commonly used within a criminal justice system: people charged with crimes may be imprisoned until their trial; those pleading or being found guilty of crimes at trial may be sentenced to a specified period of imprisonment. In simplest terms, a prison can also be described as a building in which people are legally held as a punishment for a crime they have committed. Prisons can also be used as a tool of political repression by authoritarian regimes. Their perceived opponents may be ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Physical Quantities
A physical quantity is a physical property of a material or system that can be quantified by measurement. A physical quantity can be expressed as a ''value'', which is the algebraic multiplication of a ' Numerical value ' and a ' Unit '. For example, the physical quantity of mass can be quantified as '32.3 kg ', where '32.3' is the numerical value and 'kg' is the Unit. A physical quantity possesses at least two characteristics in common. # Numerical magnitude. # Units Symbols and nomenclature International recommendations for the use of symbols for quantities are set out in ISO/IEC 80000, the IUPAP red book and the Quantities, Units and Symbols in Physical Chemistry, IUPAC green book. For example, the recommended symbol for the physical quantity ''mass'' is ''m'', and the recommended symbol for the quantity ''electric charge'' is ''Q''. Subscripts and indices Subscripts are used for two reasons, to simply attach a name to the quantity or associate it with another quanti ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Units Of Luminous Intensity
Unit may refer to: Arts and entertainment * UNIT, a fictional military organization in the science fiction television series ''Doctor Who'' * Unit of action, a discrete piece of action (or beat) in a theatrical presentation Music * ''Unit'' (album), 1997 album by the Australian band Regurgitator * The Units, a synthpunk band Television * ''The Unit'', an American television series * '' The Unit: Idol Rebooting Project'', South Korean reality TV survival show Business * Stock keeping unit, a discrete inventory management construct * Strategic business unit, a profit center which focuses on product offering and market segment * Unit of account, a monetary unit of measurement * Unit coin, a small coin or medallion (usually military), bearing an organization's insignia or emblem * Work unit, the name given to a place of employment in the People's Republic of China Science and technology Science and medicine * Unit, a vessel or section of a chemical plant * Blood unit, a measurement ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Lighting
Lighting or illumination is the deliberate use of light to achieve practical or aesthetic effects. Lighting includes the use of both artificial light sources like lamps and light fixtures, as well as natural illumination by capturing daylight. Daylighting (using windows, skylights, or light shelves) is sometimes used as the main source of light during daytime in buildings. This can save energy in place of using artificial lighting, which represents a major component of energy consumption in buildings. Proper lighting can enhance task performance, improve the appearance of an area, or have positive psychological effects on occupants. Indoor lighting is usually accomplished using light fixtures, and is a key part of interior design. Lighting can also be an intrinsic component of landscape projects. History With the discovery of fire, the earliest form of artificial lighting used to illuminate an area were campfires or torches. As early as 400,000 years ago, fire was kindl ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
