Geiger-Muller detecting tube

If the voltage applied to a Geiger-Muller tube is increased from zero, no response to radiation is detected despite the presence of a radioactive isotope... 

The emission from the radioisotopes is often insufficient to penetrate the window of a Geiger-Muller counter. Therefore, the compound whose activity is to be measured is often mixed in solution with a scintillator, called a fluor, which transforms / rays into luminescence proportional to the number of /3 particles emitted. The sample is dissolved in a solvent (toluene, xylene or dioxane, the latter being used for water-soluble compounds) that acts as a relay to transfer the energy to the scintillator. The scintillation mixture contains PPO (2,5-diphenyloxazole), which emits in the UV and POPOP, which emits in the visible and is well adapted to detection with photomultiplier tubes (Fig. 17.2). The quantum yield of emission will depend on the energy of the emitted particles. 

Another method of radiation detection that has value in biochemistry is the use of gas ionization chambers The most common device that uses this technique is the Geiger-Muller tube (G-M tube). When j8 particles pass through a gas, they collide with atoms and may cause ejection of an electron from a gas atom. This results in the formation of an ion pair made up... 

Neon In advertising signs, because it glows red when electricity is passed through it In the helium-neon gas laser (Figure 11.11) In Geiger-Muller tubes, which are used for the detection of radioactivity... 

In-line detection. In the treatment of solutions containing americium the americium 241 content of solutions leaving the chromatography columns is continuously monitored. The gamma detector is a miniature Geiger-Muller tube placed in contact with the solution outlet pipe. The unit is shielded from ambient irradiation by lead. 

Geiger-Muller tube A radiation-detection device operating on the principle that ions form when radiation passes through a tube filled with low-pressure gas. 

Figure 10.5 A cross section of a detection tube used in Geiger-Muller counters.

The first reported application of tomography was probably that of Grohse (1955), who investigated the variation in density of a bed of silicon powder as a function of fluidizing velocity. At almost the same time Bartholomev and Casagrande (1957) used Co ° as y-ray source to monitor a 20.4" i.d. FCC unit and detected the y-rays by a Geiger-Muller tube. 

A number of chemical elements contain unstable nuclides. The nuclei of these chemical elements break up spontaneously with the emission of ionizing radiation (Table 2.3). These unstable nuclides are described as radioactive and are called radionuclides. The radiation is of three distinct types and their properties are summarized in Table 2.3. Radiation can be detected and measured using a Geiger-Muller tube (Figure 2.16). 

Geiger-MUller counter an instrument that detects and measures the intensity of radiation by counting the number of electric pulses that pass between the anode and the cathode in a tube filled with gas contador de Geiger-MUller un instrumento que detecta y mide la intensidad de la radiacion contando el numero de pulsos electricos que pasan entre el dnodo y el catodo en un tubo lleno de gas... 

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