Portable counters

Although brief and incomplete, our findings indicate that the labelling of suspected food species with or other beta-emitting radionuclides is practical in research on food chains of fishes. Also, preliminary results of such work can be obtained in the field with suitably sensitive portable counters. 

Schweizer HP. 1992. Allelic exchange in Pseudomonas aeruginosa using novel ColEl-type vectors and a family of cassettes containing a portable oriT and the counter-selectable Bacillus subtilis sacB marker. Mol Microbiol 6 1195-204. 

Minor spills must be cleaned first with absorbent blotter paper and then thoroughly rinsed with water. Always wear gloves during cleanup. Dispose of the blotter paper in the Solid Radioactive Waste container. The spill area should then be checked with a portable G-M counter. 

After final clean-up of all contaminated glassware and the work area, remove your gloves and thoroughly wash your hands with soap and warm water. Use a portable G-M counter to check for contamination on your hands, clothes, and work area in the laboratory. Report any areas of unusually high count (above 200 cpm) to your instructor. 

The portable instrumentation and low power demands of stripping analysis satisfy many of the requirements for on-site and in situ measurements of trace metals. Stripping-based automated flow analyzers were developed for continuous on-line monitoring of trace metals since the mid-1970s [16,17]. These flow systems involve an electrochemical flow detector based on a wall-jet or thin-layer configuration along with a mercury-coated working electrode, and downstream reference and counter electrodes. 

Hiac PC4000 portable liquid particle counter is a contamination measurement tool, designed to run on-line analyses of hydraulic systems and fluids. The fully self-contained counter operates in the light-blocking mode using a laser diode and reports contamination levels at 4, 6, 10, 14, 21,38 and 70 pm at a flow rate of 60 ml min. ... 

Accdg to Ref 49, p6, in all velocity work with cannon, conducted now for US Ordn Corps either the camera chronograph or counter chronograph is taken as the standard. When both instruments are employed, the velocity reported is the mean of the two values F. Field Chronograph. This includes any self-contained detection and time measuring device designed for field use. One of such instruments, the Remington Chronoscope, is completely portable. Its principles of oper-... 

Detectors filled with certain gases or gas mixtures are designed to capture and measure the ions produced by radiation within the detector. Gas-filled detectors used to measure radioactivity include the (1) ionization chamber, (2) proportional counter, and (3) Geiger counter. Of the three, the Geiger counter is used in the clinical chemistry laboratory as a portable radiation monitor. 

A more recent, and very promising, development is due to Cohen and James, who adapted a position-sensitive proportional counter to stress measurement. This counter has the great advantage that it can measure the 29 position of a diffracted beam without a 29 movement of the counter (Sec. 7-5). Preliminary work was done with the counter mounted on a standard diffractometer [16.10]. Later a portable instrument was made, in which the counter and a miniature, air-... 

Radioactive elements can be detected by a Geiger counter. This portable instrument maintains an electric circuit between its battery and a handheld, gas-filled cylinder. There is normally a gap in the circuit. If radiation is present, ions are formed in the gas. The charged particles complete the circuit, which activates a sounding device and a meter. 

Toms, A. M., Initial Screening Tests Portable Particle Counters , J. Lubr. Fluid Power, 3(4), 9-12, Nov 2002. 

There is a split cell tester available commercially, however, which uses an ingenious mechanical system to counter-balance friction so that the tester is inexpensive and field-portable. The machine is a refinement of the device developed by Warren Spring Laboratories for research use the assembly has been made more compact and robust, suitable for site, works or lab use. 

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