We developed a single-particle optical particle counter with polarization detection(SOPC)for the real-time measurement of the optical size and depolarization ratio(defined as the ratio of the vertical component to the...We developed a single-particle optical particle counter with polarization detection(SOPC)for the real-time measurement of the optical size and depolarization ratio(defined as the ratio of the vertical component to the parallel component of backward scattering)of atmospheric particles,the polarization ratio(DR)value can reflect the irregularity of the particles.The SOPC can detect aerosol particles with size larger than 500 nm and the maximum particle count rate reaches~1.8×10^(5)particles per liter.The SOPC uses a modulated polarization laser to measure the optical size of particles according to forward scattering signal and the DR value of the particles by backward S and P signal components.The sampling rate of the SOPC was 106#/(sec·channel),and all the raw data were processed online.The calibration curve was obtained by polystyrene latex spheres with sizes of 0.5-10μm,and the average relative deviation of measurement was 3.96% for sub 3μm particles.T-matrix method calculations showed that the DR value of backscatter light at 120°could describe the variations in the aspect ratio of particles in the above size range.We performed insitu observations for the evaluation of the SOPC,the mass concentration constructed by the SOPC showed good agreement with the PM_(2.5)measurements in a nearby state-controlled monitoring site.This instrument could provide useful data for source appointment and regulations against air pollution.展开更多
Nanoparticles have recendy attracted extensive attention in view of their great potential in biomedicine and bioanalytical applications. Single particle detection via light scattering offers a simple and efficient app...Nanoparticles have recendy attracted extensive attention in view of their great potential in biomedicine and bioanalytical applications. Single particle detection via light scattering offers a simple and efficient approach for the size, size distribution, and concentration analysis of nanoparticles. In particular, intrinsic heterogeneity or rare events masked by ensemble averaging can be revealed. However, the sixth power dependence of Rayleigh scattering on particle size makes it very challenging to detect individual nanoparficles of small sizes. This article is intended to provide an overview of recent progress in the development of techniques based on light scattering for the detection of single nanoparticles.展开更多
基金supported by the Research and Development of Instruments and Equipments,Chinese Academy of Sciences(No.YJKYYQ20200009)。
文摘We developed a single-particle optical particle counter with polarization detection(SOPC)for the real-time measurement of the optical size and depolarization ratio(defined as the ratio of the vertical component to the parallel component of backward scattering)of atmospheric particles,the polarization ratio(DR)value can reflect the irregularity of the particles.The SOPC can detect aerosol particles with size larger than 500 nm and the maximum particle count rate reaches~1.8×10^(5)particles per liter.The SOPC uses a modulated polarization laser to measure the optical size of particles according to forward scattering signal and the DR value of the particles by backward S and P signal components.The sampling rate of the SOPC was 106#/(sec·channel),and all the raw data were processed online.The calibration curve was obtained by polystyrene latex spheres with sizes of 0.5-10μm,and the average relative deviation of measurement was 3.96% for sub 3μm particles.T-matrix method calculations showed that the DR value of backscatter light at 120°could describe the variations in the aspect ratio of particles in the above size range.We performed insitu observations for the evaluation of the SOPC,the mass concentration constructed by the SOPC showed good agreement with the PM_(2.5)measurements in a nearby state-controlled monitoring site.This instrument could provide useful data for source appointment and regulations against air pollution.
基金supported by the National Natural Science Foundation of China (20675070, 20975087, 90913015 & 21027010)Program for New Century Excellent Talents in University (NCET-07-0729)+1 种基金Research Fund for the Doctoral Program of Higher Education of China (20090121120008 & 20090121110009)the National Fund for Fostering Talents of Basic Science (J1030415)
文摘Nanoparticles have recendy attracted extensive attention in view of their great potential in biomedicine and bioanalytical applications. Single particle detection via light scattering offers a simple and efficient approach for the size, size distribution, and concentration analysis of nanoparticles. In particular, intrinsic heterogeneity or rare events masked by ensemble averaging can be revealed. However, the sixth power dependence of Rayleigh scattering on particle size makes it very challenging to detect individual nanoparficles of small sizes. This article is intended to provide an overview of recent progress in the development of techniques based on light scattering for the detection of single nanoparticles.
