Low power ultrasonic cleaners can remove fine particles from surface by adding soot. 低出力の超音波洗浄機でも、ススを添加すれば表面からサブミクロン粒子を剥離できる


The study proposed a novel method of recovering (collecting) sub-micron particles deposited on a substrate by using an aqueous suspension of soot particles and ultrasonic treatment. すす粒子の水性懸濁液と超音波処理を用いて基板上に堆積したサブミクロン粒子を回収 (捕集) する新しい方法を提案した。きっかけとして、大気中に浮遊する微粒子を捕集した固体表面から微粒子を脱離する必要がありました。It is known to be difficult to remove submicron particles from the surface. 表面からサブミクロン粒子を剥離するのは難関であることが知られている。

新しい微粒子の回収法 (a novel particle collector system)

FREE ACCESS: doi.org/10.1252/jcej.16we319

研究室の発表論文の紹介(Introduction of papers from our group) >> https://tag/paper/

100 nm から1μm(sub-micron)粒子は大気中に浮遊する物質の中で最も高い個数濃度であり、その観測や化学分析が気候変動の予測に不可欠。高精度な化学分析は液相を用いる手法も多く、大気中微粒子を固体表面(例えばフィルター)に捕集し、液体へ導入させる。しかし、固体表面上に堆積したsub-micron粒子を高い効率で剥離させることが難しい課題とされてきた。




100 nm to 1 μm (sub-micron) particles are said to have the highest number concentrations of any airborne material. In order to perform detailed chemical analysis, it is often necessary to collect atmospheric particles on a filter (solid substrate) and transfer them to a liquid phase. However, it has been a difficult task to release the sub-micron particles deposited on the solid surface with high efficiency.

A protocol for the detachment of submicron (100-1000 nm) particulate samples deposited on flat substrates and their collection in aqueous samples is proposed based on a suspension-assisted ultrasonic method. As samples, combustion-made magnesium oxide (MgO) aggregates in the submicron size range were deposited in the gas phase onto three kinds of substrates: a silicon wafer and coarse and fine alumina-coated resin sheets. To enhance the sample particle detachment, a solid–liquid suspension made of candle combustion soot particles (having average sizes between 100-200 nm) was selected as an ultrasound propagation medium, which is different from the usual liquid medium, such as water, a surfactant solution, or a solvent.

Experiments were performed using low-power (42kHz and 35W) ultrasonication, and the substrates and suspensions were analyzed using scanning electron microscopy (SEM) images and particle size distributions based on dynamic light scattering (DLS), respectively.

Soot particles were produced by a candle burning

The detachment using the medium with soot had a higher efficiency compared to that without soot, and there was an optimum soot concentration for particle detachment for all three substrates. The suspension particle size distribution after ultrasonication showed good dispersion of the sample particles in the soot suspension.

Collaborator in this study: Prof. Koji Masuda. 桝田教授(生体医用システム工学科)Department of Biomedical Engineering TUAT https://web.tuat.ac.jp/~biome/lab_Masuda.htm

Short Introduction of our other papers – 研究室が発表した論文の紹介 (empatlab.net)