Collection of Particulate Matters in Exhaust Gas Using the Attractive Force Induced by Surface Charging

Keiichiro Yoshida
Chemosphere ◽  
2019 ◽  
Vol 223 ◽  
pp. 399-405 ◽  
Satoshi Asaoka ◽  
Tomohisa Dan ◽  
Ichiro Asano ◽  
Shinjiro Hayakawa ◽  
Kazuhiko Takeda

T.C. Sheu ◽  
S. Myhajlenko ◽  
D. Davito ◽  
J.L. Edwards ◽  
R. Roedel ◽  

Liquid encapsulated Czochralski (LEC) semi-insulating (SI) GaAs has applications in integrated optics and integrated circuits. Yield and device performance is dependent on the homogeniety of the wafers. Therefore, it is important to characterise the uniformity of the GaAs substrates. In this respect, cathodoluminescence (CL) has been used to detect the presence of crystal defects and growth striations. However, when SI GaAs is examined in a scanning electron microscope (SEM), there will be a tendency for the surface to charge up. The surface charging affects the backscattered and secondary electron (SE) yield. Local variations in the surface charge will give rise to contrast (effectively voltage contrast) in the SE image. This may be associated with non-uniformities in the spatial distribution of resistivity. Wakefield et al have made use of “charging microscopy” to reveal resistivity variations across a SI GaAs wafer. In this work we report on CL imaging, the conditions used to obtain “charged” SE images and some aspects of the contrast behaviour.

Crisis ◽  
2005 ◽  
Vol 26 (1) ◽  
pp. 25-33 ◽  
Elizabeth King ◽  
Neil Frost

Abstract. A retrospective suicide study revealed that the Forestry Commission car parks in the New Forest in southern England were a previously unrecognized magnet for nonlocal suicides, attracting as high a proportion of “visitors” (35/43 in 1993-97) as among suicides who jumped from the cliffs at the infamous Beachy Head (39/48 in 1993-97). Over 95% of the car park suicides died from car exhaust gas poisoning. A multiagency initiative aimed to reduce the number of suicides in the 140 New Forest car parks where restricting access was impossible, and environmental issues paramount. Signs displaying the Samaritans' national telephone number were erected in the 26 car parks in which 50% of the car park suicides had occurred. Numbers, location, and residence of all car park deaths were monitored for 3 years. Corresponding changes in other forest registration districts were also monitored. During the 3-year intervention period the number of car park suicides fell significantly from 10/year, 1988-1997, to 3.3/year. The average annual total number of suicides in the New Forest registration district also decreased. No significant changes were found in comparable forest districts. The number of suicides in the New Forest car parks remained low during the 2 years following the evaluation.

2020 ◽  
Vol 14 (4) ◽  
pp. 7481-7497
Yousef Najjar ◽  
Abdelrahman Irbai

This work covers waste energy utilization of the combined power cycle by using it in the candle raw material (paraffin) melting process and an economic study for this process. After a partial utilization of the burned fuel energy in a real bottoming steam power generation, the exhaust gas contains 0.033 of the initially burned energy. This tail energy with about 128 ºC is partly driven in the heat exchanger of the paraffin melting system. Ansys-Fluent Software was used to study the paraffin wax melting process by using a layered system that utilizes an increased interface area between the heat transfer fluid (HTF) and the phase change material (PCM) to improve the paraffin melting process. The results indicate that using 47.35 kg/s, which is 5% of the entire exhaust gas (881.33 kg/s) from the exit of the combined power cycle, would be enough for producing 1100 tons per month, which corresponds to the production quantity by real candle's factories. Also, 63% of the LPG cost will be saved, and the payback period of the melting system is 2.4 years. Moreover, as the exhaust gas temperature increases, the consumed power and the payback period will decrease.

2020 ◽  
Vol 54 (4) ◽  
pp. 267-276
Koshi Yamamoto ◽  
Yuta Suzuki ◽  
Gochoobazar Oyunjargal ◽  
Hiroyuki Fukuda ◽  
Munkhtsetseg Oidov ◽  

2021 ◽  
Noopur Joshi ◽  
Noah Becker ◽  
Roger Tull ◽  
James Kenna ◽  
Christopher Adams ◽  

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