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  2. Mass fraction (chemistry) - Wikipedia

    en.wikipedia.org/wiki/Mass_fraction_(chemistry)

    Mass fraction can also be expressed, with a denominator of 100, as percentage by mass (in commercial contexts often called percentage by weight, abbreviated wt.% or % w/w; see mass versus weight). It is one way of expressing the composition of a mixture in a dimensionless size ; mole fraction (percentage by moles , mol%) and volume fraction ...

  3. Amine value - Wikipedia

    en.wikipedia.org/wiki/Amine_value

    It is the number of Nitrogens x 56.1 (Mwt of KOH) x 1000 (convert to milligrams) divided by molecular mass of the amine functional compound. So using Tetraethylenepentamine (TEPA) as an example: Mwt = 189, number of nitrogen atoms = 5 So 5 x 1000 x 56.1/189 = 1484. So the Amine Value of TEPA = 1484

  4. Acid value - Wikipedia

    en.wikipedia.org/wiki/Acid_value

    The volume and normality of the sodium hydroxide are used, along with the weight of the sample, to calculate the free fatty acid value. [3] Acid value is usually measured as milligrams of KOH per gram of sample (mg KOH/g fat/oil), or grams of KOH per gram of sample (g KOH/g fat/oil). [5]

  5. Useful conversions and formulas for air dispersion modeling

    en.wikipedia.org/wiki/Useful_conversions_and...

    For example, such a regulation might limit the concentration of NOx to 55 ppmv in a dry combustion exhaust gas corrected to 3 volume percent O 2. As another example, a regulation might limit the concentration of particulate matter to 0.1 grain per standard cubic foot (i.e., scf) of dry exhaust gas corrected to 12 volume percent CO 2.

  6. Mass concentration (chemistry) - Wikipedia

    en.wikipedia.org/wiki/Mass_concentration_(chemistry)

    In chemistry, the mass concentration ρ i (or γ i) is defined as the mass of a constituent m i divided by the volume of the mixture V. [1]= For a pure chemical the mass concentration equals its density (mass divided by volume); thus the mass concentration of a component in a mixture can be called the density of a component in a mixture.

  7. Air pollutant concentrations - Wikipedia

    en.wikipedia.org/wiki/Air_pollutant_concentrations

    PM is most usually (but not always) expressed as mg/m 3 of air or other gas at a specified temperature and pressure. For gases, volume percent = mole percent; 1 volume percent = 10,000 ppmv (i.e., parts per million by volume) with a million being defined as 10 6.

  8. Parts-per notation - Wikipedia

    en.wikipedia.org/wiki/Parts-per_notation

    In mining, it is also equivalent to one gram per metric ton, expressed as g/t. One part per billion (ppb) denotes one part per 1,000,000,000 (10 9) parts, and a value of 10 −9. This is equivalent to about three seconds out of a century. One part per trillion (ppt) denotes one part per 1,000,000,000,000 (10 12) parts, and a value of 10 −12 ...

  9. Total base number - Wikipedia

    en.wikipedia.org/wiki/Total_Base_Number

    BN generally ranges from 6–8 mg KOH/g in modern lubricants, 7–10 mg KOH/g for general internal combustion engine use and 10–15 mg KOH/g for diesel engine operations. BN is typically higher for marine grade lubricants , approximately 15-80 mg KOH/g, as the higher BN values are designed to increase the operating period under harsh operating ...