Thermo Scientific 5030i SHARP, Инструкция по эксплуатации

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Introduction
Principle of Operation
1-4 Model 5030 i SHARP Instruction Manual Thermo Fisher Scientific
The SHARP optical assembly senses the light scattered by the aerosol
passing through an 880 nm illumination beam. The nephelometry response
is linear with aerosol concentration; independent of sample flow rate; and a
running one-minute average and dynamic average are continuously
calculated. A relative humidity (RH) measurement is located at the sample
filter-tape assuring a representative measurement of the aerosol
conditioning prior to real-time mass determination.
Thereafter, the aerosol is deposited onto a glass fiber filter tape. The filter
tape will accumulate an aerosol sample towards a threshold value,
whereupon the filter tape will automatically advance prior to reaching
saturation. During the collection of aerosol onto the filter tape the SHARP
Monitor uses the radiometric principle of beta attenuation through a
known sample area to continuously collect and detect the deposited mass.
Additionally, the beta-attenuation chamber measures alpha emissions from
the accumulated aerosol and excludes negative mass artifacts from the
presence of daughter nuclides from radon gas decay to achieve a “refined
mass” measurement. Simultaneous refined mass measurement and sample
volume measurement through a calibrated orifice provide a continuous
concentration measurement of the ambient mass concentration.