摘要
气溶胶发生系统是校准大气颗粒物测量仪器、研究纳米颗粒物特性和开展烟雾箱模拟实验的必备仪器之一.针对现有气溶胶发生仪器稳定性差和不利于外场监测等缺点,本研究设计了一款新型纳米气溶胶发生系统(包括气溶胶发生器和扩散干燥管),并通过搭建实验系统对该仪器的工作性能进行了测试.在性能测试中使用氯化钠(NaCl)-水溶液和癸二酸二辛酯(DOS)-异丙醇溶液分别产生固态NaCl和液态DOS气溶胶,利用扫描电迁移率粒径谱仪测试生成气溶胶的粒径分布.测试结果表明,通过调节溶液浓度(0.01～0.50 g·L-1)和载气流量(1.64～3.67 L·min-1),生成不同大小(几何平均粒径:25～51nm)和不同数浓度(106～107个·cm-3)的气溶胶.对仪器稳定性能测试发现,在3 h的测试时间里生成的气溶胶几何平均粒径变化小于6%,数浓度变化小于12%.
Aerosol nanoparticle generation is a key step in calibrating aerosol instruments, examining nanoparticle properties, and investigating aerosol formation mechanism in photochemical smog systems. An aerosol nanoparticle generation system （including an atomizer and a diffusion dryer） was developed and evaluated in this study. Aqueous solution of NaCl and isopropanol solution of DOS are used to generate solid and liquid aerosols, and the size distribution is measured by a scanning mobility particle spectrometer （SMPS）. With the concentration of 0.01-0.50 g·L-1 and the carrying gas flow rate of 1.64-3.67 L·min-1, generated aerosols have the geometric mean diameter of 25-51 nm and the total number concentration of 106-107 cm-3. The stability of the generation system was demonstrated. During the three-hours consecutive operation, the variations of the geometric mean diameter and the total number concentration are less than 6% and 12%, respectively.
出处
《环境科学》
EI
CAS
CSCD
北大核心
2013年第8期2950-2954,共5页
Environmental Science
基金
国家大学生创新性实验计划项目
国家自然科学基金项目(41227805)
北京市自然科学基金项目(8122025)
关键词
气溶胶发生器
扩散干燥管
几何平均粒径
数浓度
稳定性
aerosol generation system
diffusion dryer
geometric mean diameter
number concentration
stability
