• Journal of the Korean Society for Marine Environment & Energy
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• v.2 no.1
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• pp.34-39
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• 1999

Removal of spilled oil over the sea and the river has become one of the urgent problems in these days. Removing oil using mechanical devices by adhesion method is known to be closely related with the problem of estimating the thickness of film remaining on the surface of solid withdrawn from a quiescent liquid. In the present study a series of experimental results are compared with the analytic estimation for the thickness of film remaining on the solid surface using non-dimensional analysis. For the case of pure water both results show the remarkable agreement. However, discrepancy has been found for the case of Bunker C oil and diesel oil. The analytic estimation over-predicts the experimental value for the case of Bunker C oil and under-predicts it for the case of diesel oil. Further study is required to investigate the real situation including a contact angle and the property difference between oil and water.

• Journal of the Korean Chemical Society
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• v.67 no.3
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• pp.165-174
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• 2023

The development of all-solid-state batteries (ASSBs) has been gaining attention in recent years due to their potential to offer higher energy densities, improved safety, and longer cycle life compared to conventional lithium-ion batteries. However, several challenges must be addressed to achieve the practical application of ASSBs, such as the development of high-performance solid-state electrolytes, stable electrode-electrolyte interfaces, and cost-effective manufacturing processes. In this review paper, we present an overview of the current state of ASSB research, including recent progress in solid-state electrolyte and cathode/anode materials, and cell architecture. We also summarize the recent advancements and highlight the remaining challenges in ASSB research, with an outlook on the future of this promising technology.

• Korean Chemical Engineering Research
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• v.54 no.4
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• pp.448-452
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• 2016

This study is for the effective pretreatment and saccharification of lignocellulosic biomass for a transport fuel receiving attention. The waste water during the pretreatment of biomass is major factor for determining the price of biofuel. Therefore, we conducted high concentration of organosolv pretreatment for decline waste water and reusing the solvent. We confirmed effect of organosolv pretreatment by components analysis and enzymatic hydrolysis of pretreated biomass. The corn stover was used for and 99.5 wt% of ethanol as a organosolv pretreatment. The pretreatment condition was varied 130 to $190^{\circ}C$ during the designated reaction times and the effect of pretreatment was investigated by enzymatic hydrolysis. The highest glucose conversion was more than 68% the pretreatment condition of $190^{\circ}C$ for 70 min or more. The solid remaining was more than 70% and almost of cellulose and hemicellulose were survived.

• 한국생물공학회:학술대회논문집
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• 2000.11a
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• pp.711-712
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• 2000

DNA probe assay comprising a microwell as' solid matrix for the immobilization of streptavidin (SA) and an oligonucleotide with covalently bound fluorecein as detection probe was developed. The insolubilized SA captured the biotinylated DNA product of polymerase chain reaction (PCR), and the product was denatured under a basic condition. The remaining single-stranded DNA on the solid surface was hybridized with the probe for signal generation that was performed based on enzyme-linked immuno -reactions.

• Bulletin of the Korean Chemical Society
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• v.29 no.5
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• pp.911-912
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• 2008

• 한국신재생에너지학회:학술대회논문집
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• 2008.10a
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• pp.59-62
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• 2008

The performance behavior of solid oxide fuel cell using reformate gas as fuels was investigated. When the pre-reformate gas was used without steam, the maximum power density was 50% lower than that using H2. This may be due to carbon deposition caused by the pyrolysis of remaining hydrocarbons. However, when the steam was added, the maximum power density showed a relatively small variation according to reformate gas. When pre-reformate gas with steam was fed into anode, the SOFC showed the stable performance without sharp voltage drop during 10h operation.

• 한국신재생에너지학회:학술대회논문집
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• 2009.11a
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• pp.313-320
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• 2009

Indonesian Ministry of Environment estimates that each year 170 cities and regencies in Indonesia produce 45,764,354.30 $m^3$ or approximately 11,441,091.08 ton of solid waste. Unfortunately, unsustainable management system has created a severe waste problem, hazardous to health and environment. This paper deals with the problem and offers some solutions. They are 3R (Reduce Reuse and Recycle), waste-to-energy concept and landfill gas (LFG) utilization. While 3R policy has been adopted by the government, the remaining two technologies are still dormant. Thus the paper provides a complete yet compact analysis of technology, economics, and environment aspect of waste-to-energy and LFG. Given the facts of waste production and management in Indonesia, the purpose is to encourage Government of Indonesia and other stake holders (including international community) to explore and exploit this potential. Potential of reducing waste negative externality while receiving extra revenue. Two bird with a stone.

• Bulletin of the Korean Chemical Society
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• v.29 no.6
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• pp.1173-1178
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• 2008

A simple and sensitive high-performance liquid chromatographic method was developed for the simultaneous identification of enrofloxacin and its active metabolite ciprofloxacin in chicken muscle. Norflorxacin imprinted polymers synthesized in water-containing systems show high selectivity to enrofloxacin and ciprofloxacin in an aqueous environment. Using these water-compatible imprinted polymers as selective adsorbents in the solid-phase extraction of enrofloxacin and ciprofloxacin from chicken samples, the remaining biological matrix could be quickly washed out from the imprinted column while enrofloxacin and ciprofloxacin were selectively retained and enriched. Analytical separation was performed on a $C_{18}$ column using acetonitrile-water as a mobile phase and fluorescence detection. Good linearity was obtained from 0.8 to 500 ng/g (r > 0.998) with relative standard deviation of less than 3.9%. The mean recoveries of enrofloxacin and ciprofloxacin from chicken muscle were 80.6-94.5% and 77.8-91.8% at three different concentrations. The limits of determinations based on S/N=3 were 0.07 ng/g and 0.09 ng/g, which are below the maximum residue limits established in many countries.

• Journal of the Korea Institute of Military Science and Technology
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• v.7 no.4 s.19
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• pp.125-132
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• 2004

The radial slot configuration in the solid propellant grain is usually fabricated by the polyurethane foam slot former The foam cannot be easily removed from the solid propellant, some can remain in the slot. Analogue solid propellant rocket motors using polyurethane foam to shape the slot are static fired with the foam former still in place in the slot. The pressure increases at the slot part are measured and there are indications of the propellant cracks at the insulations above the slot. The pressure increase is produced at the beginning of the burning sequence as the foam will hinder the combustion gas of the burning propellant from flowing into the central bore. The pressure increase up to about 300psi is predicted for the motor tested and this pressure increase depends on the gap between the propellant and foam surfaces and remaining foam volume. This amount of pressure increase inside of the slot is estimated to cause the propellant crack. To prevent this pressure increase, minimizing the foam remainder in the slot and making sufficient chamfering at the comer of the slot entrance are suggested.

• Solar Energy
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• v.5 no.2
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• pp.77-83
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• 1985

An analysis is performed to investigate the influence of the buoyancy force and the thickness variation of melting layer in the containment that is filled with phase-change Material surrounding a cylindrical heating tube during melting process. The phase-change material is assumed to be initially solid at its phase-change temperature and the remaining solid at any given time is still at the phase-change temperature and neglecting the effect of heat transfer occuring within the solid. At the start of melting process, the thickness of melting layer is assumed to be a stefan-problem and after the starting process, the change of temperature and velocity is calculated using a two dimensional finite difference method. The governing equations for velocity and temperature are solved by a finite difference method which used SIMPLE (Semi Implicit Method Pressure linked Equations) algorithm. Results are presented for a wide range of Granshof number and in accordance with the time increment and it is founded that two dimensional fluid flow occurred by natural convection decreases the velocity of melting process at the bottom of container. The larger the radius of heating tube, the higher heat transfer is occurred in the melting layer.