• Journal of the Korean Society of Clothing and Textiles
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• v.10 no.2
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• pp.59-67
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• 1986

To control the amounts of formaldehyde released from the cotton fabric finished with N-methylol compounds, glycerol was used as a formaldehyde-scavenging agent. It was observed the effects of catalysts and curing conditions when aftertreated with glycerol on melamine resin finished fabric. The effects of Different processes of glycerol treatment, and different resins, urea resin and melamine resin, were compared. The conclusions obtained from the results are as follows: 1) It was shown hatt the aftertreatment with glycerol (treated without catalyst) was more effective than treated with catalysts in controlling free formaldehyde. 2) The optimum curing temperature and curing time for the glycerol aftertreatment without adversely affecting the other properties of fabric was about $160^{\circ}C$, 3 min. 3) According to the increase of glycerol concentration in both aftertreatment and simultaneous treatment the amounts of free formaldehyde was reduced. The rate of decrease was manifest within the limits of $6\%$ in the case of simultaneous treatment with glycerol ana resins, and $3\%$ in the case of glycerol aftertreatment on resin finished fabrics. 4) Dry wrinkle recovery angle was decreased the increase of glycerol concentration. Melamine resin had a little adverse effect than urea resin, particulary glycerol aftertreatment. 5) The breaking strength was increased with the increase of glycerol concentration.

• Transactions of the Korean Society of Automotive Engineers
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• v.7 no.7
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• pp.113-121
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• 1999

Diesel particulate matter is known to be one of the major harmful emissions produced by diesel engines. Diesel particulates are subject to diesel emission regulations and have lately become the focus in the diesel emission control technology. Thus, the aftertreatment system is adopted at the diesel engine exhaust to reduce the particulate emission. Although this benefit is recognized, it is not clear how the aftertreatment system influences quantitatively the particle size distribution distribution. In this study, the particle size distributions of diesel exhaust were measured using the scanning mobility particle sizer with and without the aftertreatment system. There results showed that the diesel particulate filter and plasm system reduced the number of emitted particles by more than 90% and about 80% respectivley in the particle size range of 20nm∼600nm. On the other hand no significant effect of the diesel oxidation catalyst on the particle number concentration was detected.

• Textile Coloration and Finishing
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• v.5 no.2
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• pp.117-124
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• 1993

The Silk fabric was dyed with various acid dyes, and than treated with copper sulfate or copper sulfate/thiourea. Munsell color system, dye exhaustion and light fastness were investigated for the treated fabrics. The results obtaind are as follows: 1) The color variation of the silk-dyed fabric by aftertreatment with copper sulfate was shown redish, but original color with copper sulfate/thiourea. 2) Copper sulfate/thiourea was much more effective than copper sulfate only to increase the light fastness. 3) The crease recovery was increased by aftertreatment with copper sulfate/thiourea. 4) Dye exhaustion and tensile strength of the silk-dyed fabric by aftertreatment with copper sulfate was decreased about 8-15% more than those of untreated.

• Textile Coloration and Finishing
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• v.5 no.4
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• pp.1-9
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• 1993

The Cotton fabric was dyed with various directd dyes, and then treated with copper sulfate or copper sulfate/thiourea. Munsell color system, dye exhaustion, tensile strength, light fastness, washing fastness and rubbing fastness were investigated for the treated fabrics. The results obtaind are as follows: 1. The color variation of the cotton-dyed fabric by aftertreatment with copper sulfate was shown redish, but original color with copper sulfate/thiourea. 2. Copper sulfate/thiourea was much more effective than copper sulfate only to increase the light fastness, washing fastness and rubbing fastness. 3. Dye exhaustion of the cotton-dyed fabric by aftertreatment with copper sulfate was decreased about 20% more than those of untreated. 4. Tensile stregth of cotton-dyed fabric by aftertreatment with copper sulfate/thiourea was decrease about 10% more than those of untreated.

• Transactions of the Korean Society of Automotive Engineers
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• v.18 no.5
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• pp.124-129
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• 2010

The direct injection (DI) diesel engine has become a prime candidate for future transportation needs because of its high thermal efficiency. However, nitrogen oxides (NOx) increase in the local high temperature regions and particulate matter (PM) increases in the diffusion flame region within diesel combustion. Therefore, the demand for developing hybrid system consist of exhaust gas recirculation (EGR) and aftertreatment system as well as diesel particulate filter (DPF) or lean NOx trap (LNT) should be applied. The variation of EGR rate due to the malfunction of EGR valve can affect not only the combustion stability of engine but also the performance of aftertreatment system. In this research, 2.0 liter 4-cylinder turbocharged diesel engine was used to investigate the combustion and emission characteristics for various operating conditions with EGR. While the fuel consumption was increased with increase of EGR rate, NOx emission was improved by maximum 90% at low speed, low load operating condition. To achieve combustion stability and reliability of aftertrearment system with minimum penalty in fuel consumption and emissions, the fault diagnosis of EGR malfunction must be employed.

• Journal of the Korean Society of Clothing and Textiles
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• v.3 no.2
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• pp.29-36
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• 1979

In order to control free formaldehyde release from fabric finished with urea-formaldehyde precondensate, the resin finished fabric was padded in urea or acylamide solution, dried and cured at $140^{\circ}C$. The effect of aftertreatment with urea or acrylamide on free formaldehyde release and on characteristics of resin finished fabric were examined. It was shown that aftertreatment with urea was effective to control free formaldehyde release, the free formaldelyde content in aftertreated fabric could be reduced from 900 ppm to 200 ppm and formaldehyde release under accelerated storage condition was also reduced from 8000 ppm to 1000 ppm. Polyacrylamide formed in the fiber during aftertreatment appeared to be a formaldehyde capture. Especially by washing the aftertreated fabric, the ability to control formaldehyde release under accelerated condition was not dimimished in contrast with aftertreated with unea. It suggests that polyacrylamide can be used as a formaldehyde capture which withstand diminution from washing.

• Transactions of the Korean Society of Automotive Engineers
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• v.9 no.6
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• pp.8-15
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• 2001

An aftertreatment system of diesel exhaust gas was attempted to extract particulate matters. The system consisted of a corona-less electrostatic precipitator to agglomerate soot particles and a counter-flow cyclone to collect them. When the effect of high voltage was examined at different configuration of electrode plates, the case of positive 15kV at both plates showed the maximum reduction of 38% in diesel smoke level. However, the back pressure became quite high as engine speed increased, so that minimizing pressure drop in cyclone should be studied with improving collection efficiency of soot particles.

• Textile Coloration and Finishing
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• v.26 no.4
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• pp.311-321
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• 2014

In this study, Aftertreatment properties of PCM/Nylon sheath/core fabrics have been determined. Especially, the relationship between finishing property and content including of PCM ratio. Samples of PCM/Nylon fabrics were monitored, separately, with 2% o.w.f solutions of each of the berberine chloride, cetylpyridinium chloride(CPC), benzyldimethylhexadecyl ammonium chloride(BDHAC) and dodecyltrimetyl ammonium bromide(DTAB). Various temperatures and liquor ratio and pH conditions were also studied to optimize aftertreatment properties. Berberine chloride finished sample showed the good color fastness. Cetylpyridinium chloride(CPC) finished sample showed very effective antibacterial properties against Staphylococcus aureus and Klebsiella pneumoniae.

• Transactions of the Korean Society of Automotive Engineers
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• v.22 no.3
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• pp.1-11
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• 2014

The aim of this study is to investigate the effect of SCR reactor on the exhaust emissions characteristics in order to develop a urea-SCR aftertreatment system for reducing $NO_x$ emissions. The experiments are conducted by using a flue tube LPG steam boiler with the urea-SCR aftertreatment system. The urea-SCR aftertreatment system utilizes the ammonia converted from 17% aqueous urea solution injected in front of SCR catalyst as a reducing agent for reducing $NO_x$ emissions. The equivalence ratio, urea injection amount, ammonia slip and $NO_x$ conversion efficiency relative to boiler load are applied to discuss the experimental results. In this experiment, the average equivalence ratio is calculated by changing only the fuel consumption rate while the intake air amount is constantly fixed at $25,957.11cm^3/sec$. The average equivalence ratios are 1.38, 1.11, 0.81 and 0.57 when boiler loads are 100, 80, 60 and 40%. The $NO_x$ conversion efficiency is raised with increasing urea injection amount, and $NH_3$ slip is also boosted at the same time. Consequently, the $NO_x$ conversion efficiency relative to boiler load should be examined in combination with urea injection amount and $NH_3$ slip. The results are calculated by 89, 85, 77 and 79% for the boiler loads of 100, 80, 60 and 40%. The appropriate amount of urea injection for the respective boiler load can be not discussed by only $NO_x$ emissions, and should be determined by considering the $NO_x$ conversion efficiency, $NH_3$ slip and reactive activation temperature simultaneously. In this study, the urea amounts of 230, 235, 233 and 231 mg/min are injected at the boiler loads of 100, 80, 60 and 40%, and the final $NH_3$ slips are measured by 8.48, 5.58, 11.97 and 11.34 ppm at the same conditions. THC emission is affected by the SCR reactor under other experimental conditions except 100% engine load, and CO emission at only 40% engine load. The rest of exhaust emissions are not affected by the SCR reactor under all experimental conditions.

• Journal of the korean Society of Automotive Engineers
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• v.23 no.1
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• pp.20-26
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• 2001