• International Journal of Automotive Technology
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• v.6 no.2
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• pp.95-105
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• 2005

Diesel engines have low specific fuel consumption, but high particulate emissions, mainly soot. Diesel soot is suspected to have significant effects on the health of living beings and might also affect global warming. Hence stringent measures have been put in place in a number of countries and will be even stronger in the near future. Diesel engines require either advanced integrated exhaust after treatment systems or modified engine models to meet the statutory norms. Experimental analysis to study the emission characteristics is a time consuming affair. In such situations, the real picture of engine control can be obtained by the modeling of trend prediction. In this article, an effort has been made to predict emissions smoke and NO$_{x}$ using cylinder combustion derived parameters and diesel particulate filter data, with artificial neural network techniques in MATLAB environment. The model is based on three layer neural network with a back propagation learning algorithm. The training and test data of emissions were collected from experimental set up in the laboratory for different loads. The network is trained to predict the values of emission with training values. Regression analysis between test and predicted value from neural network shows least error. This approach helps in the reduction of the experimentation required to determine the smoke and NO$_{x}$ for the catalyst coated filters.

• Conservation Science in Museum
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• v.12
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• pp.19-24
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• 2011

This study presents an investigation into the conservation process of an iron dagger and scabbard, which are a lacquered scabbard and a dagger inserted in it, excavated in the Daho-ri relic of Changwon by Gimhae National Museum. The bronze dagger whose condition was poor due to corrosion was coated with Incralac, an intensifier, to reveal the surface patterns through a microscope. The lacquered scabbard was removed of foreign substances on the surface and coated with HPC 2%(in water) to protect the film. Applied onto the surface from which foreign substances were removed was Caparol Binder 5%(in water) two to three times to form a protective film and then faced with Korean paper. Once it was fixed in a polyurethane foam in a stable manner, it was turned over to receive the same process on the back. Three layers of Korean paper were attached to the back of the scabbard to support the thin artifact. HPC 2%(in water), which was applied to the scabbard, was also applied to the iron dagger inside for cementing effect. After all the processes were completed, the artifact was put in a transparent acrylic box for future display.

• Applied Chemistry for Engineering
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• v.34 no.1
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• pp.30-35
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• 2023

The glass bead surface was coated using a TiO₂ sol, after which dry-treated (TB) and calcined (TBc) samples were prepared. Photocatalytic degradation of methylene blue and toluene, as well as characterization of the TiO₂ thin films, were carried out. The TiO₂ thin film of the TB sample had the same shape as the sponge foam, according to FE-SEM, XPS, and FTIR analyses, and contained both amorphous and crystalline TiO₂. On the other hand, crystalline TiO₂ was mainly present in the TiO₂ thin film of the TBc sample, and needle-shaped particles and tiny ones were mixed. The adsorption capacity for methylene blue and the degradation rate of the TBc sample were less than 10 % compared with those of the TB sample, and the adsorption capacity and degradation rate of the TBc sample decreased similarly as the amount of TiO₂ coating increased. The amount of toluene adsorption for the TBc sample (46 mg/g) was smaller than that of the TB sample with the same coating amount, but the degradation rate was similar. In the case of the TB sample, the degradation rate for toluene decreased less than the adsorption capacity as the amount of TiO₂ coating increased. This result is considered to be because, in the non-calcined TB sample, the active site reduction of the crystalline particles occurred less and the specific surface area of the amorphous texture decreased as the amount of TiO₂ coating increased.

• Journal of the Korean Applied Science and Technology
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• v.35 no.3
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• pp.876-885
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• 2018

Utilization of spent RHDM(Residue Hydrodemetallation) catalyst as de-NOx SCR(Selective Catalytic Reduction) catalyst was studied by conducting by heptane cleaning and high-temperature roasting for removal of deposited carbon and sulfur. Followed by oxalic acid leaching was carried out for controlling excess vanadium deposited on spent RHDM catalyst in search of appropriate vanadium loadings for the best SCR performance and the leaching conditions are 5~15wt% concentration of oxalic acid and 5min leaching time at $50^{\circ}C$ with the ultra-sonic agitator. De-NOx activities of prepared and commercial SCR catalyst were measured by the atmospheric SCR catalyst performance test unit, their residual content were also carried out by ICP, C&S Analysis and XRF. Acid leaching (AL-10) catalyst showed the highest de-NOx efficiency of all prepared catalysts and the de-NOx efficiency over wash coated catalyst(WC-AL-10) was equivalent to that of commercial SCR catalyst. Therefore the possibility of using as SCR catalyst for each application by adjusting treatment conditions of spent RHDM catalyst was found and further research will be needed in detail for the its commercialization.

• Polymer(Korea)
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• v.39 no.2
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• pp.293-299
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• 2015

Conductive microcellular foams consisted of polystrene (PS) and polydopamine-coated carbon nanotube (PDA-CNT) were prepared via high internal phase emulsion (HIPE) polymerization and their morphology and electrical conductivity were investigated. CNT as a conductive nanofiller was modified to PDA-CNT by coating with hydrophilic PDA on the surface of CNT to increase aqueous phase dispersion and emulsion stability. It was possible to prepare the HIPEs having higher PDA-CNT content and the resultant foams having improved conductivity due to its good dispersion. The foams showed the morphology of interconnected cell structure. As PDA-CNT content increased, yield stress and storage modulus increased and cell size reduced. The PDA-CNT content showing electrical percolation threshold was ca. 0.58 wt% and the conductivity at PDA-CNT content of 5 wt% was increased to $10^{-3}S/m$.