機(jī)械外文翻譯---利用超音速射流分散納米粒子的新型濕式粉碎機(jī)（英文）

1、This content has been downloaded from IOPscience. Please scroll down to see the full text.Download details:IP Address: 130.179.16.201This content was downloaded on 18/07/2014 at 10:05Please note that terms and conditions

2、 apply.Dispersion of nanoparticles by novel wet-type pulverizer utilized supersonic jet flowView the table of contents for this issue, or go to the journal homepage for more2011 IOP Conf. Ser.: Mater. Sci. Eng. 18 062017

3、(http://iopscience.iop.org/1757-899X/18/6/062017)Home Search Collections Journals About Contact us My IOPsciencenovel wet-type pulverizer utilized supersonic jet flow (hereafter referred to as supersonic wet jet mill; S

4、SJM). In this study, we have reported the dispersing result of barium titanate nanoparticles (BT-NPs) and have discussed the effect of air pressure on the dispersion by using the SSJM. 2. Experimental apparatus and pro

5、cedure 2.1. Experimental apparatus Figure1 shows schematic diagram of the SSJM (left). The right part of describes shows the internal configuration of the nozzle part. The compressed air (maximum air pressure was 0.6

6、MPa) was supplied at the top part of the nozzle. The Laval nozzle, which was used for the SSJM as shown in Figure1, is used to accelerate a compressed air passing through it to a supersonic speed, and upon expansion,

7、to form the exhaust flow so that the heat energy propelling the flow is maximally converted into kinetic energy. As a result, the injected droplets passing through the nozzle were accelerated to supersonic and were na

8、turally cooled. The suspension in the feed tank was supplied to the throat of the nozzle, while controlling the volume flow through the pump tubing. The supplied suspension had been formed droplets by jet flow and h

9、ad been accelerated inside the nozzle. The accelerated droplets had collided with the SiC plate. Most of the processed suspension was collected at the bottom tank, and some of the processed suspension was evacuated

10、 along with the jet flow, therefore, the solvent recovery tank unit attached to the exhaust line. 2.2. Experimental procedure Two kinds of BT-NP were used in this work. BT-NPs with the average particle size of 30 nm w

11、ere synthesized by the sol-gel method [3] (referred to as sol-gel BT). Commercially available BT-NPs (BT-01, Sakai Chemical Industry, Japan) with the average particle size of 100 nm were manufactured by hydrothermal m

12、ethod (referred to as hydrothermal BT). A dispersant used in this study was an ammonium salt of poly (acrylic acid) (PAA-NH4 +, Mw 8000, Touagousei, Japan). The sol-gel BT was added to ethylene glycol monomethyl ether

13、in 2 volume % (referred to as sol-gel BT suspension). PAA-NH4 + was added to distilled water in 5 wt% against powder weight and then the hydrothermal BT was added in 20 volume percents against distilled water (referred

14、 to as hydrothermal BT suspension). Each suspension was injected under various air pressures from 0.3 to 0.6 MPa. An aggregated particle size was evaluated by dynamic light scattering method (DLS, Nano-ZS, Malvern, UK

15、). A shape and microstructure of the BT-NPs were examined with a transmission electron microscope (TEM, JEM-3200EX, JEOL, Japan) and a field emission scanning electron microscope (FESEM, S-4800, Hitachi, Japan). For

16、discussing the effect of air pressure on the dispersion by use of the SSJM, size and velocity distributions of droplets were measured as follows. Distilled water was injected under various air pressures from 0.3 to 0.6

17、 MPa. The size and velocity distribution of droplets at a distance of 100 mm away from the nozzle exit were measured simultaneously by Phase Doppler Anemometry (Dantec Dynamics, Denmark) 3. Result and discussion Figur

18、e 1. Schematic diagrams of supersonic wet jet mill (left) and the nozzle part (right), showing approximate flow velocity (V), together with the effect on temperature (T) and pressure (P). ICC3: Symposium 3: Nano-Cryst