When.com Web Search

Search results

  1. Results From The WOW.Com Content Network
  2. Parts-per notation - Wikipedia

    en.wikipedia.org/wiki/Parts-per_notation

    The difference is quite significant when dealing with gases, and it is very important to specify which quantity is being used. For example, the conversion factor between a mass fraction of 1 ppb and a mole fraction of 1 ppb is about 4.7 for the greenhouse gas CFC-11 in air (Molar mass of CFC-11 / Mean molar mass of air = 137.368 / 28.97 = 4.74 ...

  3. Labeling of fertilizer - Wikipedia

    en.wikipedia.org/wiki/Labeling_of_fertilizer

    More precisely, the first number ("N value") is the percentage of elemental nitrogen by weight in the fertilizer; that is, the mass fraction of nitrogen times 100. The second number ("P value") is the percentage by weight of phosphorus pentoxide P 2 O 5. The third number ("K value") is the equivalent content of potassium oxide K 2 O. [3]

  4. 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.

  5. Sodium adsorption ratio - Wikipedia

    en.wikipedia.org/wiki/Sodium_adsorption_ratio

    The sodium adsorption ratio (SAR) is an irrigation water quality parameter used in the management of sodium-affected soils.It is an indicator of the suitability of water for use in agricultural irrigation, as determined from the concentrations of the main alkaline and earth alkaline cations present in the water.

  6. Salinity - Wikipedia

    en.wikipedia.org/wiki/Salinity

    Whatever pore size is used in the definition, the resulting salinity value of a given sample of natural water will not vary by more than a few percent (%). Physical oceanographers working in the abyssal ocean , however, are often concerned with precision and intercomparability of measurements by different researchers, at different times, to ...

  7. Milligram per cent - Wikipedia

    en.wikipedia.org/wiki/Milligram_per_cent

    Main page; Contents; Current events; Random article; About Wikipedia; Contact us; Help; Learn to edit; Community portal; Recent changes; Upload file

  8. Orders of magnitude (mass) - Wikipedia

    en.wikipedia.org/wiki/Orders_of_magnitude_(mass)

    The table at right is based on the kilogram (kg), the base unit of mass in the International System of Units . The kilogram is the only standard unit to include an SI prefix (kilo-) as part of its name. The gram (10 −3 kg) is an SI derived unit of mass.

  9. Cancer slope factor - Wikipedia

    en.wikipedia.org/wiki/Cancer_slope_factor

    Cancer slope factors (CSF) are used to estimate the risk of cancer associated with exposure to a carcinogenic or potentially carcinogenic substance. A slope factor is an upper bound, approximating a 95% confidence limit, on the increased cancer risk from a lifetime exposure to an agent by ingestion or inhalation.