Particle spectrometer counter

Compare the activity reported for the tracer solution with the activity obtained with the proportional counter and the alpha-particle spectrometer based on their respective counting efficiency (s) values, adjusted for sample volume and radioactive decay. Discuss whether the differences in activity are significant and decide which values are more reliable and should be associated with the tracer solution for subsequent measurements of plutonium. 

Step 5. Pipette 100 X of the uranium solution each onto the centers of two planchets and dry under a heat lamp. Count one with the proportional counter and then with the alpha-particle spectrometer. Save the second planchet for Part 1C, Step 8. 

The radiation detection systems employed in radioanalytical chemistry laboratories have changed considerably over the past sixty years, with significant improvement realized since the early 1980s. Advancements in the areas of material science, electronics, and computer technology have contributed to the development of more sensitive, reliable, and user-friendly laboratory instruments. The four primary radiation measurement systems considered to be necessary for the modern radionuclide measurement laboratory are gas-flow proportional counters, liquid scintillation (LS) counters. Si alpha-particle spectrometer systems, and Ge gamma-ray spectrometer systems. These four systems are the tools used to identify and measure most forms of nuclear radiation. 

In a study of the impact of printers as emission sources of VOCs, ozone and particulate matter on indoor air quality, ultrahne particles have been measured using Scanning Mobihty Particle Spectrometer-Condensation Particle Counter (SMPS-CPC) (Kagia et al. 2007). SMPS distributes from 20 to 500 nm diameter particles and CPC counts ultrahne particles. 

Knollenberg, R. G., Veal, D. L., Optical Particle Monitors, Counters and Spectrometers Performance Characterization, Comparison and Use, in Proc. Inst. Environ. Sci. Technol, San Diego, CA, 1991,pp751-771. 

Note DMS differential mobility spectrometer, SMPS scanning mobility particle sizer, CPC condensation particle counter, TDMPS twin differential mobility particle sizer, DMPS differential mobility particle sizer, OPC optical particle counter, APS aerodynamic particle sizer, MAS mass aerosol spectrometer, LAS-X optical laser aerosol spectrometer, ELPI electrical low pressure impactor... 

Alpha-particle detector Beta-particle detector Gamma-ray detector proportional counters silicon (Si) diode with spectrometer proportional counters Geiger-Muller counters liquid scintillation (LS) counters thallium-activated sodium iodide (Nal(Tl) detector with spectrometer germanium (Ge) detector with spectrometer... 

Determine counting efficiency of the proportional detector in Step 5 for three 3,000-s periods to measure alpha particles and beta particles. Record in Data Table 7.2. Also perform overnight count (50,000 s) for alpha-particle spectral analysis of the planchet to identify the uranium isotopes and any other radionuclides and to determine their relative amounts from their alpha-particle energy spectra and record results in Data Table 7.2. Count alpha- and beta-particle background in proportional counter and alpha-particle spectral background in spectrometer for at least the same periods. 

Tuch et. al. [231] ran a Mobile Aerosol Spectrometer (0.1 to 2.5 pm) and an Electrical Aerosol Spectrometer (0.5 to 10 pm) side by side for 6 weeks and found both to be reliable with almost identical results. Total number counts agreed with results from a Condensation Particle Counter. 

Cloud condensation nucleus (CCN) concentration CCN counter or spectrometer Measurements commonly made at supersaturations between 0.1% and 1%. Particles activated at the applied supersaturation grow to sizes where they can be optically detected and counted -b... 

Doki, N. Seki, H. Takano, K. Asatani, J. Yokota, M. Kubota, N. Process control of seeded batch cooling crystallization of the metastable a-form glycine using an in-situ ATR-FTIR spectrometer and an in-situ FBRM particle counter. Crystal Growth Design 2004, 4 (5), 949-953. 

As a result of the complex aerodynamics of the particle beam and associated skimmers, the size distribution of the particles that reach the ion source differs significantly from that in the gas samples from outside the system. To relate the measured chemical compositions to the outside aerosol, it is necessary to correct for this effect. This can be accomplished in principle by determining the elficiency of transmission of particles from the exterior into the chamber. It is also possible to use data for particle size distributions measured outside the spectrometer to characterize the external aerosol. Because the particle size distribution measured with an optical particle counter does not correspond to the aerodynamic diameter, there will be some difficulties of interpretation. 

Microscopic inspection of the RFS electrode as well as an automatic particle counter and shape classifier have been used to verify that the effective RFS capture range of particles from a used oil sample is from 2 pm to more than 100 pm. However, the upper particle size limit that can be completely volatilized by the spectrometer s arc is closer to 50 pm. This does not preclude the RFS analysis from detecting larger particles, because even partial volatilization of a particle above 50 pm will add signal and concentration to the analysis. The purpose of RFS analysis is to detect and trend the presence of large particles in a used oil sample that are missed by routine spectrometric analysis, and not to quantify the exact size or concentration of these... 

Older LS counter systems (see Section 8.3.2) have three channels for distinguishing energies new ones have full energy spectrometers. These are directly applicable for distinguishing alpha particles by energy. Because beta particles are emitted as a spectrum from zero to maximum energy, and the spectra have various shapes, identification of beta-particle emitters by energy is less feasible. 

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