目前中国使用的PM 2.5(大气中直径小于或等于2.5微米的颗粒物)监测设备和技术主要是依赖进口。
The equipment and technologies that China is using to monitor PM2.5 — fine particles 2.5 microns or less in diameter — are mainly from other countries.
总悬浮粒子包括被称为PM2.5的细颗粒物，即直径不超过2.5微米的颗粒。
Total suspended particulates include fine particulate matter called PM2.5 ― particles with diameters of no more than 2.5 micrometers.
美国这些数据主要是关于直径2.5微米以下污染颗粒物的。
S. government about air pollution in Beijing, based specifically on PM2.5 particles, paint a different picture.
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