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  2. Proportional counter - Wikipedia

    en.wikipedia.org/wiki/Proportional_counter

    The proportional counter is a type of gaseous ionization detector device used to measure particles of ionizing radiation.The key feature is its ability to measure the energy of incident radiation, by producing a detector output pulse that is proportional to the radiation energy absorbed by the detector due to an ionizing event; hence the detector's name.

  3. Gaseous ionization detector - Wikipedia

    en.wikipedia.org/wiki/Gaseous_ionization_detector

    The generation of discrete Townsend avalanches in a proportional counter. Proportional counters operate at a slightly higher voltage, selected such that discrete avalanches are generated. Each ion pair produces a single avalanche so that an output current pulse is generated which is proportional to the energy deposited by the radiation. This is ...

  4. List of dimensionless quantities - Wikipedia

    en.wikipedia.org/wiki/List_of_dimensionless...

    chemistry (Proportion of "active" molecules or atoms) Arrhenius number = Svante Arrhenius: chemistry (ratio of activation energy to thermal energy) [1] Atomic weight: M: chemistry (mass of one atom divided by the atomic mass constant, 1 Da) Bodenstein number: Bo or Bd

  5. Glossary of chemistry terms - Wikipedia

    en.wikipedia.org/wiki/Glossary_of_chemistry_terms

    Also acid ionization constant or acidity constant. A quantitative measure of the strength of an acid in solution expressed as an equilibrium constant for a chemical dissociation reaction in the context of acid-base reactions. It is often given as its base-10 cologarithm, p K a. acid–base extraction A chemical reaction in which chemical species are separated from other acids and bases. acid ...

  6. Counts per minute - Wikipedia

    en.wikipedia.org/wiki/Counts_per_minute

    Geiger-Müller counter with dual counts/dose rate display measuring a "point source". The dose per count is known for this specific instrument by calibration. The count rates of cps and cpm are generally accepted and convenient practical rate measurements. They are not SI units, but are de facto radiological units of measure in widespread use.

  7. Wire chamber - Wikipedia

    en.wikipedia.org/wiki/Wire_chamber

    A wire chamber or multi-wire proportional chamber is a type of proportional counter that detects charged particles and photons and can give positional information on their trajectory, [1] by tracking the trails of gaseous ionization. [2]

  8. Counting efficiency - Wikipedia

    en.wikipedia.org/wiki/Counting_efficiency

    In the measurement of ionising radiation the counting efficiency is the ratio between the number of particles or photons counted with a radiation counter and the number of particles or photons of the same type and energy emitted by the radiation source.

  9. Activity coefficient - Wikipedia

    en.wikipedia.org/wiki/Activity_coefficient

    In thermodynamics, an activity coefficient is a factor used to account for deviation of a mixture of chemical substances from ideal behaviour. [1] In an ideal mixture, the microscopic interactions between each pair of chemical species are the same (or macroscopically equivalent, the enthalpy change of solution and volume variation in mixing is zero) and, as a result, properties of the mixtures ...