enow.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

    One part per hundred thousand, per cent mille (pcm) or milli-percent denotes one part per 100,000 (10 5) parts, and a value of 10 −5. It is commonly used in epidemiology for mortality, crime and disease prevalence rates, and nuclear reactor engineering as a unit of reactivity.

  3. Talk:Parts-per notation - Wikipedia

    en.wikipedia.org/wiki/Talk:Parts-per_notation

    The examples don't seem to be too accurate. A drop is usually defined as 0.05 ml, which then gives;. 1 drop in 50 ml = 1‰, 50ml is a very small cup 1 drop in 50 l = 1ppm 50 l is about 11 gallons, not 40 1 drop in 50 cubic metres = 1 ppb 1 drop = 1ppt, a 50 m swimming pool is 50*25*2 = 2,500 m^3 1 drop in 50,000,000 cubic metres = 1ppq, 50,000,000 m^3 is equivalent to a lake covering a square ...

  4. Air pollutant concentrations - Wikipedia

    en.wikipedia.org/wiki/Air_pollutant_concentrations

    1 volume percent = 10,000 ppmv (i.e., parts per million by volume) with a million being defined as 10 6. Care must be taken with the concentrations expressed as ppbv to differentiate between the British billion which is 10 12 and the USA billion which is 10 9 (also referred to as the long scale and short scale billion, respectively).

  5. Per mille - Wikipedia

    en.wikipedia.org/wiki/Per_mille

    The word promille is the cognate in Dutch, German, Finnish and Swedish, and is sometimes seen as a loanword in English with the same meaning as per mille. [7] [4] The symbol is included in the General Punctuation block of Unicode at U+2030 ‰ PER MILLE SIGN. [5] There is also an Arabic-Indic per mille sign at U+0609 ؉ ARABIC-INDIC PER MILLE SIGN.

  6. Explosive vapor detector - Wikipedia

    en.wikipedia.org/wiki/Explosive_vapor_detector

    In the case of EVDs, the detection requirements in terms of sensitivity and selectivity are quite demanding, since the vapor pressure of most explosives or drugs is in the order of parts per trillion or even parts per quadrillion. In addition, if the target substance is well packed and wrapped, the vapor pressure is decreased further, typically ...

  7. Explosives trace detector - Wikipedia

    en.wikipedia.org/wiki/Explosives_trace_detector

    It is expressed in terms of nano-grams (ng), pico-grams (pg) or femto-grams (fg) with fg being better than pg better than ng. It can also be expressed in terms of parts per billion (ppb), parts per trillion (ppt) or parts per quadrillion (ppq). Sensitivity is important because most explosives have a low vapor pressure .

  8. Trillion - Wikipedia

    en.wikipedia.org/wiki/Trillion

    Trillion is a number with two distinct definitions: 1,000,000,000,000 , i.e. one million million , or 10 12 (ten to the twelfth power ), as defined on the short scale . This is now the meaning in both American and British English.

  9. Unit of time - Wikipedia

    en.wikipedia.org/wiki/Unit_of_time

    1/1000 d (0.001 d) 1.44 minutes, or 86.4 seconds. Also marketed as a ".beat" by the Swatch corporation. moment: 1/40 solar hour (90 s on average) Medieval unit of time used by astronomers to compute astronomical movements, length varies with the season. [4] Also colloquially refers to a brief period of time. centiday 0.01 d (1 % of a day)