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Minim (unit)
The minim (abbreviated min, or ) is a unit of volume in both the imperial and U.S. customary systems of measurement. Specifically it is of a fluid drachm or of a fluid ounce. The minim was introduced in the 1809 edition of ''The Pharmacopœia of the Royal College of Physicians of London'' as a replacement for the drop, which had previously been the smallest unit of the apothecaries' system. It was observed that the size of a drop can vary considerably depending upon the viscosity and specific gravity of the liquid. (At the time, the phenomenon of surface tension was not well understood.) The minim, on the other hand, was measured with a graduated glass tube known as a "minimometer", later known as the minim-tube. The minim-tube was a type of graduated pipette, a device invented in 1791 by François-Antoine-Henri Descroizilles. Apothecaries' measures are fully defined in the United Kingdom's Weights and Measures Act of 1878, but the UK's 1963 Weights and Measures Act p ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Units Of Measurement
A unit of measurement is a definite magnitude of a quantity, defined and adopted by convention or by law, that is used as a standard for measurement of the same kind of quantity. Any other quantity of that kind can be expressed as a multiple of the unit of measurement. For example, a length is a physical quantity. The metre (symbol m) is a unit of length that represents a definite predetermined length. For instance, when referencing "10 metres" (or 10 m), what is actually meant is 10 times the definite predetermined length called "metre". The definition, agreement, and practical use of units of measurement have played a crucial role in human endeavour from early ages up to the present. A multitude of systems of units used to be very common. Now there is a global standard, the International System of Units (SI), the modern form of the metric system. In trade, weights and measures is often a subject of governmental regulation, to ensure fairness and transparency. ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Specific Gravity
Relative density, or specific gravity, is the ratio of the density (mass of a unit volume) of a substance to the density of a given reference material. Specific gravity for liquids is nearly always measured with respect to water at its densest (at ); for gases, the reference is air at room temperature (). The term "relative density" (often abbreviated r.d. or RD) is often preferred in scientific usage, whereas the term "specific gravity" is deprecated. If a substance's relative density is less than 1 then it is less dense than the reference; if greater than 1 then it is denser than the reference. If the relative density is exactly 1 then the densities are equal; that is, equal volumes of the two substances have the same mass. If the reference material is water, then a substance with a relative density (or specific gravity) less than 1 will float in water. For example, an ice cube, with a relative density of about 0.91, will float. A substance with a relative density greater ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Units Of Volume
A unit of volume is a unit of measurement for measuring volume or capacity, the extent of an object or space in three dimensions. Units of capacity may be used to specify the volume of fluids or bulk goods, for example water, rice, sugar, grain or flour. Units According to the SI system, the base unit for measuring length is the metre. The SI unit of volume is thus the cubic metre, which is a derived unit, where: at nist.gov. Retrieved 29 June 2022. 1 m3 = 1 m • 1 m • 1 m. Comparison Forestry and timber industry British Commonwealth * Hoppus, cubic foot measure used in the Brit ...[...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Wine Gallon
A wine gallon is a unit of capacity that was used routinely in England as far back as the 14th century, and by statute under Queen Anne since 1707. Britain abandoned the wine gallon in 1826 when it adopted imperial units for measurement. The 1707 wine gallon is the basis of the United States' gallon, as well as other measures. The Imperial gallon was defined with yet another set of temperature and pressure values ( and ) To convert a wine gallon to an Imperial gallon, multiply by 0.833111. To convert an Imperial gallon to a wine gallon, multiply by 1.200320. Some research concludes that the wine gallon was originally meant to hold 8 troy pounds of wine. The 1707 British statute defines the wine gallon as – e.g. a cylinder in diameter and high,π was often approximated at the time. c. 3.785 litre – and was used to measure the volume of wine and other commercial liquids such as cooking oils and honey. A 14th-century barrel of wine contained , which equals one-eighth of the t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Microlitre
The litre (international spelling) or liter (American English spelling) (SI symbols L and l, other symbol used: ℓ) is a metric unit of volume. It is equal to 1 cubic decimetre (dm3), 1000 cubic centimetres (cm3) or 0.001 cubic metre (m3). A cubic decimetre (or litre) occupies a volume of (see figure) and is thus equal to one-thousandth of a cubic metre. The original French metric system used the litre as a base unit. The word ''litre'' is derived from an older French unit, the '' litron'', whose name came from Byzantine Greek—where it was a unit of weight, not volume—via Late Medieval Latin, and which equalled approximately 0.831 litres. The litre was also used in several subsequent versions of the metric system and is accepted for use with the SI,Bureau International des Poids et M ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metrication
Metrication or metrification is the act or process of converting to the metric system of measurement. All over the world, countries have transitioned from local and traditional units of measurement to the metric system. This process began in France during the 1790s, and is still continuing more than 200 years later, with the modern International System of Units, as the metric system has not yet been fully adopted in all countries and areas. Overview Most countries now have the metric system as their official system of weights and measures. Some have adopted it as their official system but have not yet completed the process of metrication. Some others have not made any commitment to adopting it. There is not a general consensus in the sources as to the number of countries that fall into each of these categories. According to a 2011 doctoral dissertation by Hector Vera, as of 2010, a total of seven countries had not "adopted the metric system as their exclusive system of measur ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Metric System
The metric system is a system of measurement that succeeded the decimalised system based on the metre that had been introduced in France in the 1790s. The historical development of these systems culminated in the definition of the International System of Units (SI) in the mid-20th century, under the oversight of an international standards body. Adopting the metric system is known as ''metrication''. The historical evolution of metric systems has resulted in the recognition of several principles. Each of the fundamental dimensions of nature is expressed by a single base unit of measure. The definition of base units has increasingly been realised from natural principles, rather than by copies of physical artefacts. For quantities derived from the fundamental base units of the system, units derived from the base units are used—e.g., the square metre is the derived unit for area, a quantity derived from length. These derived units are coherent, which means that they inv ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Fluid Scruple
The scruple (℈) is a small unit in the apothecaries' system, derived from the old Roman ' () unit ('' scrupulus''/''scrupulum'').__NOTOC__ Mass unit The scruple is ounce, dram, or 20 grains. It is therefore equal to 1.2959782 grams. The Roman scruple was somewhat smaller, around 1.14 g. Volume unit The fluid scruple is fluid ounce, fluid dram, 20 minims, or teaspoon, or 1 saltspoon. It is therefore equal to 1.23 milliliters. See also * Scruples (other) * Roman units * Byzantine units Byzantine units of measurement were a combination and modification of the ancient Greek and Roman units of measurement used in the Byzantine Empire. Until the reign of Justinian I (527–565), no universal system of units of measurement existe ... * Э References {{Reflist, 2 Units of volume Customary units of measurement Alcohol measurement spoons Cooking weights and measures ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
François-Antoine-Henri Descroizilles
Titration (also known as titrimetry and volumetric analysis) is a common laboratory method of quantitative chemical analysis to determine the concentration of an identified analyte (a substance to be analyzed). A reagent, termed the ''titrant'' or ''titrator'', is prepared as a standard solution of known concentration and volume. The titrant reacts with a solution of ''analyte'' (which may also be termed the ''titrand'') to determine the analyte's concentration. The volume of titrant that reacted with the analyte is termed the ''titration volume''. History and etymology The word "titration" descends from the French word ''titrer'' (1543), meaning the proportion of gold or silver in coins or in works of gold or silver; i.e., a measure of fineness or purity. ''Tiltre'' became ''titre'', which thus came to mean the "fineness of alloyed gold", and then the "concentration of a substance in a given sample". In 1828, the French chemist Joseph Louis Gay-Lussac first used ''titre'' as ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Pipette
A pipette (sometimes spelled as pipett) is a laboratory tool commonly used in chemistry, biology and medicine to transport a measured volume of liquid, often as a media dispenser. Pipettes come in several designs for various purposes with differing levels of accuracy and precision, from single piece glass pipettes to more complex adjustable or electronic pipettes. Many pipette types work by creating a partial vacuum above the liquid-holding chamber and selectively releasing this vacuum to draw up and dispense liquid. Measurement accuracy varies greatly depending on the instrument. History The first simple pipettes were made in glass, such as Pasteur pipettes. Large pipettes continue to be made in glass; others are made in squeezable plastic for situations where an exact volume is not required. The first micropipette was patented in 1957 by Dr Heinrich Schnitger (Marburg, Germany). The founder of the company Eppendorf, Dr. Heinrich Netheler, inherited the rights and started t ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Viscosity
The viscosity of a fluid is a measure of its resistance to deformation at a given rate. For liquids, it corresponds to the informal concept of "thickness": for example, syrup has a higher viscosity than water. Viscosity quantifies the internal frictional force between adjacent layers of fluid that are in relative motion. For instance, when a viscous fluid is forced through a tube, it flows more quickly near the tube's axis than near its walls. Experiments show that some stress (such as a pressure difference between the two ends of the tube) is needed to sustain the flow. This is because a force is required to overcome the friction between the layers of the fluid which are in relative motion. For a tube with a constant rate of flow, the strength of the compensating force is proportional to the fluid's viscosity. In general, viscosity depends on a fluid's state, such as its temperature, pressure, and rate of deformation. However, the dependence on some of these properties is ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Volume
Volume is a measure of occupied three-dimensional space. It is often quantified numerically using SI derived units (such as the cubic metre and litre) or by various imperial or US customary units (such as the gallon, quart, cubic inch). The definition of length (cubed) is interrelated with volume. The volume of a container is generally understood to be the capacity of the container; i.e., the amount of fluid (gas or liquid) that the container could hold, rather than the amount of space the container itself displaces. In ancient times, volume is measured using similar-shaped natural containers and later on, standardized containers. Some simple three-dimensional shapes can have its volume easily calculated using arithmetic formulas. Volumes of more complicated shapes can be calculated with integral calculus if a formula exists for the shape's boundary. Zero-, one- and two-dimensional objects have no volume; in fourth and higher dimensions, an analogous concept to the ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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