Single-particle microbeam is uniquely capable of precisely delivering a preset number of charged particles to individual cells or sub-cellular targets to be determined in vitro, It is crucial to find a reference point...Single-particle microbeam is uniquely capable of precisely delivering a preset number of charged particles to individual cells or sub-cellular targets to be determined in vitro, It is crucial to find a reference point that relates the microbeam＇s location to the microscope＇s plane, and align individual targets at this reference point for cell irradiation. To choose an appropriate reference point, an approach based on analysing the intensity distribution of fluorescence in a thin scintillator excited by traversing particles is newly developed using the CAS-LIBB single-particle microbeam, which features decisive physical signification and sufficient resolution. As its bonus, this on-line analysis provides precise and fast response to the determination of beam profile and potentially optimizes the microbeam quality by further adjusting hardware setup.展开更多
Airborne pa rt icle counters are used widely to test the air cleanliness of cleanrooms. The cur rent Chinese national standard of airborne particle counter calibration, GB6167 -85, Methods for Testing the Performance ...Airborne pa rt icle counters are used widely to test the air cleanliness of cleanrooms. The cur rent Chinese national standard of airborne particle counter calibration, GB6167 -85, Methods for Testing the Performance of Dust Particle Counter, has kept the same for more than 10 years. It is necessary to be amended in time. This paper discusses the differences between Chinese airborne particle counter calibration procedure and other new calibration procedures in other countries, and points ou t the defects of current Chinese national standard.The draft of revised Chinese National Standard is also introduced. The new revised standard, Methods for Test ing the Performance of Airborne Particle Counter, covers two level calibrations: primary and secondary. Primary calibration procedure includes testing 6 kinds of performances:sample airflow rate, false counting, particle size accuracy and re solution, particle counting stability, counting efficiency and particle concentr ation limit. Secondary calibration is a relative comparing test method to verify the counting accuracy of calibrated airborne particle counters.Finally, how to keep the calibration traceability is suggested.展开更多
文摘Single-particle microbeam is uniquely capable of precisely delivering a preset number of charged particles to individual cells or sub-cellular targets to be determined in vitro, It is crucial to find a reference point that relates the microbeam＇s location to the microscope＇s plane, and align individual targets at this reference point for cell irradiation. To choose an appropriate reference point, an approach based on analysing the intensity distribution of fluorescence in a thin scintillator excited by traversing particles is newly developed using the CAS-LIBB single-particle microbeam, which features decisive physical signification and sufficient resolution. As its bonus, this on-line analysis provides precise and fast response to the determination of beam profile and potentially optimizes the microbeam quality by further adjusting hardware setup.
文摘Airborne pa rt icle counters are used widely to test the air cleanliness of cleanrooms. The cur rent Chinese national standard of airborne particle counter calibration, GB6167 -85, Methods for Testing the Performance of Dust Particle Counter, has kept the same for more than 10 years. It is necessary to be amended in time. This paper discusses the differences between Chinese airborne particle counter calibration procedure and other new calibration procedures in other countries, and points ou t the defects of current Chinese national standard.The draft of revised Chinese National Standard is also introduced. The new revised standard, Methods for Test ing the Performance of Airborne Particle Counter, covers two level calibrations: primary and secondary. Primary calibration procedure includes testing 6 kinds of performances:sample airflow rate, false counting, particle size accuracy and re solution, particle counting stability, counting efficiency and particle concentr ation limit. Secondary calibration is a relative comparing test method to verify the counting accuracy of calibrated airborne particle counters.Finally, how to keep the calibration traceability is suggested.
