• Journal of the Korean Graphic Arts Communication Society
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• v.28 no.2
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• pp.87-99
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• 2010

The ink which is left by sealed more than 6 months, it clogs head nozzle of machine due to precipitation and coagulation. In addition, if you stop printing about 3~4 hours in the middle of printing work, the head nozzles of printer could be naturally clogged. To prevent of this situation, worker should implement cleaning and checking head nozzle before hands. When the nozzle is clogged in the middle of work, running a head cleaning mode can clear the clogged nozzle. Yet, large amount of waste inks which are passed clogged nozzle will be remained after cleaning. It would be very nice that ink companies take the waste ink back by green marketing, but none of them are doing it currently. The purpose of this research is that making a black water-based recycle ink by waste inks which are left of nozzle clogging or passed expiration date. This recycle ink will improved working environment and reduce cost of disposing waste inks. Furthermore, it is very environment friendly and economical. It is called a recycle ink which is water-based black ink made by waste inks.

• Korean Journal of Materials Research
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• v.19 no.9
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• pp.473-480
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• 2009

In order to provide the mechanism of nozzle clogging, recovered nozzles for high strength steel grade were examined carefully after continuous casting. The thickness of clogged material in SEN is increased in the following order: from the bottom to the top of the nozzle, upper part of slag line, and the pouring hole. Nozzle clogging material begins to form due the adhesion of metal to nozzle wall, the decarburization, and reduction of oxide in the refractory by Al and Ti in the melt. The reduction of oxide in the refractory by Al and Ti improves the wettability of the melt on the refractory and forms a thin Al-Ti-O layer. Metal containing micro alumina inclusions is solidified on the Al-Ti-O layer, and the solid layer grows due to the heat evolution through the nozzle wall. Thermodynamic calculation has been made for the related reactions. The effect of superheat to the nozzle clogging is discussed on ultra low carbon steel and low carbon steel.

• Journal of KIBIM
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• v.7 no.3
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• pp.1-10
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• 2017

3D concrete printing technology builds structural components layer-by-layer with concrete extruded through a nozzle without using forms. This technology can simplify construction processes by optimizing design flexibility, construction time, and cost. Furthermore, the 3D printing technology is easy to make an irregularly shaped and function embedded building(or object) which is difficult to be constructed by conventional construction method. However, the 3D printing concrete is not suitable for current commercial standard and the material itself. It is also difficult to apply it to the construction site due to the lack of initial strength and the nozzle which is clogged during the process. The research of mix proportion design process for 3D printing concrete which differs from the conventional concrete is necessary in order to solve the problems. This paper aims to calculate the 3D printing concrete mix proportion design process based on the mix materials and performance information derived from the previous researches. Therefore, the usage variation range, mutual influence relationship, and the importance priority of the mix proportion are analyzed. Based on this results, the basic design process of 3D printing concrete which contains planning design phase, basic design phase and validating performance phase is suggested. We anticipate to confirm applicability verification about the actual production by referring to this 3D printing concrete mix proportion study. In the future, this study can be utilized for blueprint of the 3D printing concrete mix proportion.

• Journal of Korean Society of Water and Wastewater
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• v.27 no.2
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• pp.261-272
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• 2013

Algae boom (Red tide) in south coastal area of Korea has been appeared several times during a decade. If algae boom appears in the desalination plant, media filter and UF filter are clogged quickly, and the plant should be shutdown. In general, Algae can be removed from water by flotation better than by sedimentation, because of the low density of algal cell. The purpose of this study conducts the CFD simulation of DAF flotation basin to apply the design of the dissolved air flotation with ball filter in the Test Bed for SWRO desalination plant. In this study, Eulerian-Eulerian multiphase model was applied to simulate the behavior of air bubbles and seawater. Density difference model and gravity were used. But de-sludge process and mass transfer between air bubbles and seawater were ignored. Main parameter is hydraulic loading rate which is varied from 20 m/hr to 27.5 m/hr. Geometry of flotation basin were changed to improve the DAF performance. According to the result of this study, the increase of hydraulic loading rate causes that the flow in the separation basin is widely affected and the concentration of air is increased. The flow pattern in the contact zone of flotation basin is greatly affected by the location of nozzle header. When the nozzle header was installed not the bottom of the contact zone but the above, the opportunity of contact between influent and recycle flow was increased.

• Journal of Bio-Environment Control
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• v.8 no.4
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• pp.281-287
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• 1999

In order to take a good look at effectiveness of cooling of Fog system and Pad-Fan system, we chose 49 farm households which were installed evaporative cooling system and 2 farm households which were installed Pad-Fan system and Fog system for a test. We execute the test on 29 households out of 49.6 households, which were installed Pad-Fan system, were able to use; however, 6 household out of 9 which were installed Fog system couldn't use it. The main reason was the clogged on nozzle. The cooling efficiency on Pad-Fan system was 77.4%, but it was very poor on Fog system. Since there are many problems on Fog system, we need more research on size of fog, the location of nozzle, control of Fog systems.

• Bulletin of the Korean Chemical Society
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• v.33 no.2
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• pp.464-468
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• 2012

Three solvent systems, chlorobenzene (ink 1), chlorobenzene/o-dichlorobenzene (ink 2) and chlorobenzene/tetrahydronaphthalene (ink 3), were compared as printable inks for the fabrication of polymer light-emitting diodes (PLEDs) using poly[2-methoxy-5-(2-ethylhexyl-oxyl)-1,4-phenylenevinylene (MEH-PPV) as an emissive material and an inkjet printer (Fujifilm Dimatix DMP-2831). Ink 1 clogged the printer's nozzle and gave non-uniform film. Inks 2 and 3 were used to fabricate PLEDs with ITO/PEDOT:PSS/MEH-PPV/LiF/Al configurations. The best performance (turn-on voltage, 3.5 V; luminance efficiency, 0.17 cd/A; luminance, 1,800 cd/m) was obtained when ink 3 was used to form the emissive layer (thickness, 49 nm), attributable to the better morphology and suitable thickness of the MEH-PPV layer.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.27 no.2
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• pp.197-205
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• 2003

A cascade impactor is a multistage impaction device used to separate airborne particles into aerodynamic size classes. A micro-orifice impactor uses micro-orifice nozzles to extend the cut sizes of the lower stages to as small as 0.05 ${\mu}{\textrm}{m}$ in diameter without resorting to low pressures or creating excessive pressure drops across the impactor stages. In this work, the phenomenon of particle clogging in micro-orifice nozzles was experimentally investigated for a commercial micro-orifice uniform deposit impactor (MOUDI). It was observed, using an optical microscope, that the micro-orifice nozzles of the final stages were partially clogged due to particle deposition during the aerosol sampling. Therefore the pressure drops across the nozzles were higher than the nominal values given by the manufacturer. To examine the effect of particle clogging in micro-orifice nozzles, the particle collection efficiency of the MOUDI was evaluated using an electrical method for fine particles with diameters in the range of 0.1-0.6 ${\mu}{\textrm}{m}$. The monodisperse liquid dioctyl sebacate (DOS) particles were used as test aerosols. A faraday cage was employed to measure the low-level current of the charged particles upstream and downstream of each stage. It was found that the collection efficiency curves shifted to correspond to smaller orifice sizes, and the 50-% cutoff sizes were much smaller than those given by the manufacturer for the three stages with nozzles less than 400 ${\mu}{\textrm}{m}$ in diameter.