• Applied Chemistry for Engineering
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• v.29 no.6
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• pp.759-764
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• 2018

3D porous carbon electrodes (cNPIM), prepared by solution casting of a polymer of intrinsic microporosity (PIM-1) followed by nonsolvent-induced phase separation (NIPS) and carbonization are presented. In order to effectively control the pore size of 3D porous carbon structures, cNPIM was prepared by varying the THF ratio of mixed solvents. The SEM analysis revealed that cNPIMs have a unique 3D macroporous structure having a gradient pore structure, which is expected to grant a smooth and easy ion transfer capability as an electrode material. In addition, the cNPIMs presented a very large specific surface area ($2,101.1m^2/g$) with a narrow micropore size distribution (0.75 nm). Consequently, the cNPIM exhibits a high specific capacitance (304.8 F/g) and superior rate capability of 77% in an aqueous electrolyte. We believe that our approach can provide a variety of new 3D porous carbon materials for the application to an electrochemical energy storage.

• Analytical Science and Technology
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• v.21 no.3
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• pp.222-228
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• 2008

On living skin the chances of a successfully developing latent fingerprint are very limited. This is due to the fact that continual perspiration and rapid absorption diffuse into the lipophillic layer on skin. A study was conducted to investigate effectively developing method of latent fingerprints on human skin surfaces and pig skin likely corpse's skin. We used commercial fingerprint powder, black powders, black magnetic powder, fluorescence magnetic powder, Cyanoacrylate fuming (CA) and direct lifting methods (lifting paper, glasses and photo glossy paper). Developing of fresh fingerprints on living skin was achieved with S-powderblack, CA fuming and CA fuming following S-powder, fluorescence powder. The other powder tends to overwhelm the latent print and the background. But, latent fingerprint residue was disappeared with time after deposit on a living surface. In case of pig skin likely corpse's skin, latent fingerprint detection was achieved with CA fuming following S-powder and deposited print during 6 hr at $25^{\circ}C$, 40% relative moisture yielded excellent fingerprints with clear ridge details using 1 min CA fuming. And enhancement of fingerprint detection image using forensic light source was achieved.

• Culinary science and hospitality research
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• v.21 no.6
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• pp.303-311
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• 2015

This study was carried out to evaluate the possibility of polyols for coating material of chewing gum. Five polyols xylitol, maltitol, isomalt, erythritol, and sorbitol were compared the coating quality, coating and drying time, and color differences. Maltitol was evaluated to be the best quality for coating the gum, whereas erythritol and sorbitol were not considered for coating materials for gum. These results derived from irregular surface layer and low productivity due to increased coating time. According to changes in color of chewing gum, samples coated maltitol and xylitol and isomalt stored at high temperature. In addition, color difference of sample coated maltitol was calculated 2.88 stored at $80^{\circ}C$ for 1 day, but those of xylitol and maltitol were highly evaluated. Sample coated maltitol in polypropylene bag was stored and measured for 1 month. Changes in color of sample was slightly occurred at below $40^{\circ}C$ and the color difference was not more than 3 at $60^{\circ}C$. Chewing gum coated maltitol as coating material was expected more stable in the quality of color during distribution. Current study was performed to color changes during storage, further study will be proceeded about shelf-life of chewing gum coated polyols.

• Journal of the Korean GEO-environmental Society
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• v.10 no.4
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• pp.5-13
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• 2009

The runoff-reducing facilities using infiltration was considered for the sustainable and sound water management. However, for practical utilization, many problems are attended and therefore effort on improvements are required. In this study, methods of improvement for infiltration facilities proposed by Infiltration-Storage System (ISS) and the effect of runoff reduction were analyzed by hydraulic experimental study. In order to analyze the infiltration characteristics of proposed runoff reduction facilities in this study, it was applied to various rainfall condition and surface material considering development and urbanization influences. As a results of hydraulic model experiment, Infiltration-Storage System (ISS) made addition to effect of reduction by lower layer of accumulative infiltration quantities. And then as rainfall-intensity was increased, accumulative infiltration rates were increased in this study. Thus, Infiltration-Storage system (ISS) was more efficient than existing runoff reduction facilities because of increasing infiltration rate. Such a result was guaranteed application of ISS as runoff-reducing facilities. Therefore, ISS is expected to be capable for practical application if subsequent research for improvements are followed. Additionally, results of this study are expected to provide fundamental research data on infiltration facilities.

• Journal of Energy Engineering
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• v.20 no.3
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• pp.191-199
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• 2011

The char burn-out and NOx emissions from sub-bituminous coal were investigated in drop tube furnace under $O_2/N_2$ and $O_2/CO_2$ environments with different $O_2$ concentrations of 12, 21 and 31%. Results show that the char burn-out rate is faster as $O_2$ concentration increases higher and char burn-out rate under $O_2/CO_2$ decreases due to the lower oxygen diffusion into coal surface through the $CO_2$ rich boundary layer. NO concentration increases with increasing $O_2$ concentration, but declines at $O_2$ concentration of 31%. Meanwhile, NO emission indexes decreases monotonically with increasing $O_2$ concentration, which indicates that more NO reduction occurs with higher $O_2$ concentration probably due to greater HCN formation. For all conditions of $O_2$ concentration, the NO concentration under $O_2/N_2$ maintains higher than those of $O_2/CO_2$ due to presence of thermal NO.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.19 no.3
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• pp.241-248
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• 1986

New Paint, Stapol N-6200D, products from Song Woun Industrial Co. Ltd., was tested on its chemical effect on fouling organisms attached to fishing nets. Two kinds of fishing nets with different mesh size, 5 mm (cage culture net) and 33 mm (set net) were painted and attached to $1m^2$ PVC quadrates. The quadrates with painted or non-painted fishing nets were placed at the surface water layer of southern coast of Korea. Monthly species composition and abundance of fouling organisms were analysed as well as total weight of fouling organisms including mud on fishing nets. On the other hand, anti-fouling effect of the organisms and mud on different color paints was studied and the durability of chemical effect of painted fishing net on fouling organisms was also estimated.

• Membrane Journal
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• v.22 no.3
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• pp.171-177
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• 2012

Effect of humic acid (HA), photo-oxidation and adsorption with periodic $N_2$ back-flushing was investigated in hybrid process of ceramic ultrafiltration and photocatalyst for drinking water treatment. It was compared and investigated with the previous result at water back-flushing in viewpoints of membrane fouling resistance ($R_f$), permeate flux (J), and total permeate volume ($V_T$). As decreasing HA, $R_f$ decreased dramatically and J increased, and finally $V_T$ was the highest at HA 2 mg/L. As HA concentration increased from 2 to 10 mg/L, the membrane fouling resistance after 180 mins' operation ($R_{f,180}$) improved 0.8 times more than that of water back-flushing. Therefore, HA concentration should affect on the membrane fouling at $N_2$ back-flushing than water back-flushing. Turbidity treatment efficiencies were almost constant independent of HA concentration, but HA treatment efficiency was the maximum at HA 2 mg/L. This means that adsorption and photo-oxidation of photocatalyst beads could removed HA at HA 2 mg/L, but it was not enough at 4 mg/L. Beyond HA 6 mg/L, UF could effectively treat HA by thick cake layer on membrane surface and severe inner membrane fouling.

• KSCE Journal of Civil and Environmental Engineering Research
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• v.29 no.4D
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• pp.491-497
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• 2009

This paper presents the results of accelerated pavement tests (APT) that simulate permanent deformation (rutting) of asphalt concrete pavements under different temperatures and loading courses. Also, finite element (FE) analysis has been conducted to predict the test results. Test section for APT is the same as one of test sections at Korea Expressway Corporation test road and is subjected to a constant moving dual tire wheel load of APT at three different temperatures: 30, 40, $50^{\circ}C$. The moving wheel is applied at different loading courses within a 75cm wide wheel path to account for traffic wandering. Also, the effect of wandering on permanent deformation development is investigated numerically with three wandering schemes. In this study, ABAQUS is adopted to model APT pavement section with plain stain elements and creep strain rate model is used to take into account viscoplastic stain of asphalt concrete mixtures, and elastic layer properties are back-calculated from FWD measurements. Plus, the effect of boundary condition and subgrade on FE permanent deformation predictions is investigated. A full FE model that accounted for subgrade provided more realistic rut depth predictions, indicating subgrade has contributed to surface rutting.

• Restorative Dentistry and Endodontics
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• v.35 no.2
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• pp.69-79
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• 2010

The purpose of this study was to evaluate the effect of film thickness of various resin cements on bonding efficiency in indirect composite restoration by measurement of microtensile bond strength, polymerization shrinkage, flexural strength and modulus, fractographic FE-SEM analysis. Experimental groups were divided according to film thickness (< $50\;{\mu}m$-control, $50\;{\mu}m$-T50, $100\;{\mu}m$-T100, $150\;{\mu}m$-T150) using composite- based resin cements (Variolink II, Duo-Link) and adhesive-based resin cements (Panavia F, Rely X Unicem). The data was analyzed using ANOVA and Duncan's multiple comparison test (p < 0.05). The results were as follows ; 1. Variolink II showed higher microtensile bond strength than that of adhesive-based resin cements in all film thickness (p < 0.05) but Duo-Link did not show significant difference except control group (p > 0.05). 2. Microtensile bond strength of composite-based resin cements were decreased significantly according to increasing film thickness (p < 0.05) but adhesive-based resin cements did not show significant difference among film thickness (p > 0.05). 3. Panavia F showed significantly lower polymerization shrinkage than other resin cements (p < 0.05). 4. Composite-based resin cements showed significantly higher flexural strength and modulus than adhesive-based resin cements (p < 0.05). 5. FE-SEM examination showed uniform adhesive layer and well developed resin tags in composite-based resin cements but unclear adhesive layer and poorly developed resin tags in adhesive-based resin cements. In debonded surface examination, composite-based resin cements showed mixed failures but adhesive-based resin cements showed adhesive failures.

• Journal of Sericultural and Entomological Science
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• v.53 no.1
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• pp.6-11
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• 2015

Antheraea yamamai silkworm cocoon is considered as a natural biocompatible materials, but can not be used as medical resources due to its difficult processability. In this study, we examined the general characteristics including cocoon shell weight and structural and thermal properties of Antheraea yamamai silkworm cocoon. The cocoon shell weight and thickness of wild silkworm cocoon was 0.528 g and 0.424 mm, respectively. The cocoon has yellow-green color in outside cocoon but white in inner layer cocoon. Amino acid analysis showed that the main amino acid of Antheraea yamamai cocoon is alanine, glycine, serine, aspartic acid, tyrosine and arginine. X-ray diffractometry showed that strong diffraction peaks at $2{\theta}=16.8^{\circ}$, $20.4^{\circ}$, corresponded to ${\beta}$-sheet structure and sharp diffraction peaks at $2{\theta}=15.0^{\circ}$, $24.3^{\circ}$, $30.0^{\circ}$ due to the presence of calcium oxalate on cocoon surface. Antheraea yamamai cocoon was degraded at $370^{\circ}C$. These results might be used as basic information for development of non-textile materials using Anthereae yamamai silkworm cocoon.