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Partial Specific Volume
The partial specific volume \bar, express the variation of the extensive volume of a mixture in respect to composition of the masses. It is the partial derivative of volume with respect to the mass of the component of interest. :V=\sum _^n m_i \bar, where \bar is the partial specific volume of a component i defined as: :\bar=\left( \frac \right)_. The PSV is usually measured in milliLiters (mL) per gram (g), proteins > 30 kDa can be assumed to have a partial specific volume of 0.708 mL/g. Experimental determination is possible by measuring the natural frequency of a U-shaped tube filled successively with air, buffer and protein solution. Properties The sum of partial specific volumes of a mixture or solution is an inverse of density of the mixture namely the specific volume of the mixture. :v = \sum_i w_i\cdot \bar = \frac :\sum_i \rho_i \cdot \bar = 1 Notes See also *Partial molar property *Apparent molar property In thermodynamics, an apparent molar property of a solutio ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Partial Derivative
In mathematics, a partial derivative of a function of several variables is its derivative with respect to one of those variables, with the others held constant (as opposed to the total derivative, in which all variables are allowed to vary). Partial derivatives are used in vector calculus and differential geometry. The partial derivative of a function f(x, y, \dots) with respect to the variable x is variously denoted by It can be thought of as the rate of change of the function in the x-direction. Sometimes, for z=f(x, y, \ldots), the partial derivative of z with respect to x is denoted as \tfrac. Since a partial derivative generally has the same arguments as the original function, its functional dependence is sometimes explicitly signified by the notation, such as in: :f'_x(x, y, \ldots), \frac (x, y, \ldots). The symbol used to denote partial derivatives is ∂. One of the first known uses of this symbol in mathematics is by Marquis de Condorcet from 1770, who used it for ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Litre
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] |
Gram
The gram (originally gramme; SI unit symbol g) is a Physical unit, unit of mass in the International System of Units (SI) equal to one one thousandth of a kilogram. Originally defined as of 1795 as "the absolute weight of a volume of pure water equal to Cube (algebra), the cube of the hundredth part of a metre [1 Cubic centimetre, cm3], and at Melting point of water, the temperature of Melting point, melting ice", the defining temperature (~0 °C) was later changed to 4 °C, the temperature of maximum density of water. However, by the late 19th century, there was an effort to make the Base unit (measurement), base unit the kilogram and the gram a derived unit. In 1960, the new International System of Units defined a ''gram'' as one one-thousandth of a kilogram (i.e., one gram is Scientific notation, 1×10−3 kg). The kilogram, 2019 redefinition of the SI base units, as of 2019, is defined by the International Bureau of Weights and Measures from the fixed numeric ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Specific Volume
In thermodynamics, the specific volume of a substance (symbol: , nu) is an intrinsic property of the substance, defined as the ratio of the substance's volume () to its mass (). It is the reciprocal of density (rho) and it is related to the molar volume and molar mass: :\nu = \frac = \rho^ = \frac The standard unit of specific volume is cubic meters per kilogram (m3/kg), but other units include ft3/lb, ft3/slug, or mL/g. Specific volume for an ideal gas is related to the molar gas constant () and the gas's temperature (), pressure (), and molar mass () as shown: Since PV = and n = \frac : \nu = \frac = \frac Applications Specific volume is commonly applied to: * Molar volume * Volume (thermodynamics) * Partial molar volume Imagine a variable-volume, airtight chamber containing a certain number of atoms of oxygen gas. Consider the following four examples: * If the chamber is made smaller without allowing gas in or out, the density increases and the specific volume decreases ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Partial Molar Property
In thermodynamics, a partial molar property is a quantity which describes the variation of an extensive property of a solution or mixture with changes in the molar composition of the mixture at constant temperature and pressure. It is the partial derivative of the extensive property with respect to the amount (number of moles) of the component of interest. Every extensive property of a mixture has a corresponding partial molar property. Definition The partial molar volume is broadly understood as the contribution that a component of a mixture makes to the overall volume of the solution. However, there is more to it than this: When one mole of water is added to a large volume of water at 25 °C, the volume increases by 18 cm3. The molar volume of pure water would thus be reported as 18 cm3 mol−1. However, addition of one mole of water to a large volume of pure ethanol results in an increase in volume of only 14 cm3. The reason that the increase is differe ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Apparent Molar Property
In thermodynamics, an apparent molar property of a solution component in a mixture or solution is a quantity defined with the purpose of isolating the contribution of each component to the non-ideality of the mixture. It shows the change in the corresponding solution property (for example, volume) per mole of that component added, when all of that component is added to the solution. It is described as ''apparent'' because it appears to represent the molar property of that component ''in solution'', provided that the properties of the other solution components are assumed to remain constant during the addition. However this assumption is often not justified, since the values of apparent molar properties of a component may be quite different from its molar properties in the pure state. For instance, the volume of a solution containing two components identified as solvent and solute is given by : V=V_0 + ^\phi_1 \ =\tilde_ n_ + ^\phi\tilde_1 n_1 \, where is the volume of the pure s ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
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