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  2. Parts-per notation - Wikipedia

    en.wikipedia.org/wiki/Parts-per_notation

    In science and engineering, the parts-per notation is a set of pseudo-units to describe small values of miscellaneous dimensionless quantities, e.g. mole fraction or mass fraction. Since these fractions are quantity-per-quantity measures, they are pure numbers with no associated units of measurement. Commonly used are parts-per-million (ppm, 10 ...

  3. Air pollutant concentrations - Wikipedia

    en.wikipedia.org/wiki/Air_pollutant_concentrations

    mg/m 3 = milligrams of pollutant per cubic meter of air at sea level atmospheric pressure and T: ppmv = air pollutant concentration, in parts per million by volume T = ambient temperature in K = 273. + °C 0.082057338 = Universal gas constant in L atm mol −1 K −1: M = molecular mass (or molecular weight) of the air pollutant

  4. Blood alcohol content - Wikipedia

    en.wikipedia.org/wiki/Blood_alcohol_content

    It is also possible to use other units. For example, in the 1930s Widmark measured alcohol and blood by mass, and thus reported his concentrations in units of g/kg or mg/g, weight alcohol per weight blood. 1 mL of blood has a mass of approximately 1.055 grams, thus a mass-volume BAC of 1 g/L corresponds to a mass-mass BAC of 0.948 mg/g.

  5. Hard water - Wikipedia

    en.wikipedia.org/wiki/Hard_water

    A degree of General Hardness (dGH or 'German degree (°dH, deutsche Härte))' is defined as 10 mg/L CaO or 17.848 ppm. A Clark degree (°Clark) or English degrees (°e or e) is defined as one grain (64.8 mg) of CaCO 3 per Imperial gallon (4.55 litres) of water, equivalent to 14.254 ppm. A French degree (°fH or °f) is defined as 10 mg/L CaCO 3 ...

  6. Saline water - Wikipedia

    en.wikipedia.org/wiki/Saline_water

    v. t. e. Saline water (more commonly known as salt water) is water that contains a high concentration of dissolved salts (mainly sodium chloride). On the United States Geological Survey (USGS) salinity scale, saline water is saltier than brackish water, but less salty than brine. The salt concentration is usually expressed in parts per thousand ...

  7. Useful conversions and formulas for air dispersion modeling

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

    Wind speed conversion factors. Meteorological data includes wind speeds which may be expressed as statute miles per hour, knots, or meters per second. Here are the conversion factors for those various expressions of wind speed: 1 m/s = 2.237 statute mile/h = 1.944 knots. 1 knot = 1.151 statute mile/h = 0.514 m/s.

  8. Equivalent concentration - Wikipedia

    en.wikipedia.org/wiki/Equivalent_concentration

    For example, sulfuric acid (H 2 SO 4) is a diprotic acid. Since only 0.5 mol of H 2 SO 4 are needed to neutralize 1 mol of OH −, the equivalence factor is: feq (H 2 SO 4) = 0.5. If the concentration of a sulfuric acid solution is c (H 2 SO 4) = 1 mol/L, then its normality is 2 N. It can also be called a "2 normal" solution.

  9. List of medical abbreviations - Wikipedia

    en.wikipedia.org/wiki/List_of_medical_abbreviations

    1 dL = 100 mL DNA ... Mg magnesium mg milligram(s) MI ... ppm parts per million prn as needed from the Latin pro re nata: PT