3 天前 · Mercury is a chemical element with the symbol Hg and atomic number 80. It is commonly known as quicksilver and was formerly named hydrargyrum (/ h aɪ ˈ d r ɑːr dʒ ər ə m / hy-DRAR-jər-əm).  A heavy, silvery d-block element, mercury is the onl ...
- shiny, silvery liquid
- group 12
3 天前 · hg, the driver program of Mercurial, a version Control system. Hectogram, a unit of weight equal to 100 grams. Hyperemesis gravidarum, a complication of pregnancy. Inch of mercury, a unit of measurement for pressure.
6 天前 · Inch of Mercury INS Inertial Navigation System IPC Illustrated Parts Catalog (e.g. by Boeing, Airbus) IR Initial Release IRS inertial reference system IRT instrument rating test IRU Inertial Reference System IRVR instrumented runway visual range ...
Article list of "Wikipedia:featured lists" in English # Articles in English instance of Articles in German Languages 1 ISO 3166-1 ISO standard ISO-3166-1-Kodierliste 116 2 Moons of Jupiter Wikimedia list article Liste der Jupitermonde ...
The Planets gas fields are small natural gas producing areas in the UK sector of the southern North Sea, their names are associated with the planets and moons of the solar system. The fields started gas production from 1995, although some have ...
What is the modern chemical symbol for Mercury?
What is the unit of measurement for the Suez Canal?
What is the volume of mercury when it freezes?
What is the difference between a Lincoln and Mercury explorer?
- International Standard Atmosphere
- Standard Laboratory Conditions
- Molar Volume of A Gas
- See Also
- External Links
Before 1918, many professionals and scientists using the metric system of units defined the standard reference conditions of temperature and pressure for expressing gas volumes as being 15 °C (288.15 K; 59.00 °F) and 101.325 kPa (1.00 atm; 760 Torr). During those same years, the most commonly used standard reference conditions for people using the imperial or U.S. customary systems was 60 °F (15.56 °C; 288.71 K) and 14.696 psi(1 atm) because it was almost universally used by the oil and gas i...
Many different definitions of standard reference conditions are currently being used by organizations all over the world. The table below lists a few of them, but there are more. Some of these organizations used other standards in the past. For example, IUPAC has, since 1982, defined standard reference conditions as being 0 °C and 100 kPa (1 bar), in contrast to its old standard of 0 °C and 101.325 kPa (1 atm).The new value is the mean atmospheric pressure at an altitude of about 112 metres,...
In aeronautics and fluid dynamics the "International Standard Atmosphere" (ISA) is a specification of pressure, temperature, density, and speed of sound at each altitude. The International Standard Atmosphere is representative of atmospheric conditions at mid latitudes. In the USA this information is specified the U.S. Standard Atmosphere which is identical to the "International Standard Atmosphere" at all altitudes up to 65,000 feet above sea level.
Because many definitions of standard temperature and pressure differ in temperature significantly from standard laboratory temperatures (e.g. 0 °C vs. ~25 °C), reference is often made to "standard laboratory conditions" (a term deliberately chosen to be different from the term "standard conditions for temperature and pressure", despite its semantic near identity when interpreted literally). However, what is a "standard" laboratory temperature and pressure is inevitably geography-bound, given that different parts of the world differ in climate, altitude and the degree of use of heat/cooling in the workplace. For example, schools in New South Wales, Australia use 25 °C at 100 kPa for standard laboratory conditions.ASTM International has published Standard ASTM E41- Terminology Relating to Conditioning and hundreds of special conditions for particular materials and test methods. Other standards organizationsalso have specialized standard test conditions.
It is equally as important to indicate the applicable reference conditions of temperature and pressure when stating the molar volume of a gasas it is when expressing a gas volume or volumetric flow rate. Stating the molar volume of a gas without indicating the reference conditions of temperature and pressure has very little meaning and can cause confusion. The molar volume of gases around STP and at atmospheric pressure can be calculated with an accuracy that is usually sufficient by using the ideal gas law. The molar volume of any ideal gas may be calculated at various standard reference conditions as shown below: 1. Vm = 8.3145 × 273.15 / 101.325 = 22.414 dm3/mol at 0 °C and 101.325 kPa 2. Vm = 8.3145 × 273.15 / 100.000 = 22.711 dm3/mol at 0 °C and 100 kPa 3. Vm = 8.3145 × 298.15 / 101.325 = 24.466 dm3/mol at 25 °C and 101.325 kPa 4. Vm = 8.3145 × 298.15 / 100.000 = 24.790 dm3/mol at 25 °C and 100 kPa 5. Vm = 10.7316 × 519.67 / 14.696 = 379.48 ft3/lbmol at 60 °F and 14.696 psi (or..."Standard conditions for gases" from the IUPAC Gold Book."Standard pressure" from the IUPAC Gold Book."STP" from the IUPAC Gold Book."Standard state" from the IUPAC Gold Book.
4 天前 · Detailed list To help compare different orders of magnitude, the following list describes various lengths between metres and metres. Subatomic scale Factor () Multiple Value Item 0 0 0 Singularity 10 −35 1 Planck length 0.0000000000162 ym Planck ...
- History of Time-Measuring Devices
- External Links
The word clock derives from the medieval Latin word for 'bell'—clogga—and has cognates in many European languages. Clocks spread to England from the Low Countries, so the English word came from the Middle Low German and Middle Dutch Klocke.The word derives from the Middle English clokke, Old North French cloque, or Middle Dutch clocke, all of which mean 'bell', and stem from an Old Irishroot.
The apparent position of the Sun in the sky moves over the course of each day, reflecting the rotation of the Earth. Shadows cast by stationary objects move correspondingly, so their positions can be used to indicate the time of day. A sundial shows the time by displaying the position of a shadow on a (usually) flat surface, which has markings that correspond to the hours. Sundials can be horizontal, vertical, or in other orientations. Sundials were widely used in ancient times. With the know...
Devices that measure duration, elapsed time and intervals
Many devices can be used to mark the passage of time without respect to reference time (time of day, hours, minutes, etc.) and can be useful for measuring duration or intervals. Examples of such duration timers are candle clocks, incense clocks and the hourglass. Both the candle clock and the incense clock work on the same principle wherein the consumption of resources is more or less constant allowing reasonably precise and repeatable estimates of time passages. In the hourglass, fine sandpo...
Water clocks, along with the sundials, are possibly the oldest time-measuring instruments, with the only exceptions being the day counting tally stick. Given their great antiquity, where and when they first existed is not known and perhaps unknowable. The bowl-shaped outflow is the simplest form of a water clock and is known to have existed in Babylonand in Egypt around the 16th century BC. Other regions of the world, including India and China, also have early evidence of water clocks, but th...
The invention of the mechanical clock in the 13th century initiated a change in timekeeping methods from continuous processes, such as the motion of the gnomon's shadow on a sundial or the flow of liquid in a water clock, to periodic oscillatory processes, such as the swing of a pendulum or the vibration of a quartz crystal,which had the potential for more accuracy. All modern clocks use oscillation. Although the mechanisms they use vary, all oscillating clocks, mechanical, digital and atomic, work similarly and can be divided into analogous parts. They consist of an object that repeats the same motion over and over again, an oscillator, with a precisely constant time interval between each repetition, or 'beat'. Attached to the oscillator is a controller device, which sustains the oscillator's motion by replacing the energy it loses to friction, and converts its oscillations into a series of pulses. The pulses are then counted by some type of counter, and the number of counts is con...
Clocks are in homes, offices and many other places; smaller ones (watches) are carried on the wrist or in a pocket; larger ones are in public places, e.g. a railway station or church. A small clock is often shown in a corner of computer displays, mobile phones and many MP3 players. The primary purpose of a clock is to display the time. Clocks may also have the facility to make a loud alert signal at a specified time, typically to waken a sleeper at a preset time; they are referred to as alarm clocks. The alarm may start at a low volume and become louder, or have the facility to be switched off for a few minutes then resume. Alarm clocks with visible indicators are sometimes used to indicate to children too young to read the time that the time for sleep has finished; they are sometimes called training clocks. A clock mechanism may be used to control a device according to time, e.g. a central heating system, a VCR, or a time bomb (see: digital counter). Such mechanisms are usually cal...Baillie, G.H., O. Clutton, & C.A. Ilbert. Britten's Old Clocks and Watches and Their Makers(7th ed.). Bonanza Books (1956).Bolter, David J. Turing's Man: Western Culture in the Computer Age. The University of North Carolina Press, Chapel Hill, NC (1984). ISBN 0-8078-4108-0 pbk. Summary of the role of "the clock" in its...Bruton, Eric (1982). The History of Clocks and Watches. New York: Crescent Books Distributed by Crown. ISBN 978-0-517-37744-4.Dohrn-van Rossum, Gerhard (1996). History of the Hour: Clocks and Modern Temporal Orders. Trans. Thomas Dunlap. Chicago: The University of Chicago Press. ISBN 978-0-226-15510-4.Media related to Clocksat Wikimedia CommonsThe dictionary definition of clockat Wiktionary
5 天前 · Rome (Italian and Latin: Roma ()) is the capital city of Italy.It is also the capital of the Lazio region, the centre of the Metropolitan City of Rome, and a special comune named Comune di Roma Capitale.With 2,860,009 residents in 1,285 km 2 ...
2021/11/29 · In comparison to its predecessor, the three-door Explorer is 12.6 inches longer and 2.2 inches wider; a five-door Explorer is 22.4 inches longer and 730 pounds heavier than the Bronco II.  Again sharing a front fascia with the Ford Ranger ...