• Tribology and Lubricants
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• v.12 no.1
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• pp.36-41
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• 1996

The suitability of a pressure differential scanning calorimetry (PDSC) in monitoring the quality of synthetic base fluids has been investigated using polyalphaolefin (PAO) oils as an example. Induction period meassured at 170, 180 and 19$0^{\circ}C$, and 3.53 MPa oxygen pressure was applied to characterize their oxidation stability. The PDSC method has proven to be simple and repeatable and requires only small sample size for testing. More importantly, it can be applied in differentiating the oxidation performance quality of PAO oils and is versatile enough for use in studying kinetic aspects of PAO oil oxidation which include the effect of temperature and antioxidant concentration. Additionally, the method appears to correlate well with a rotary bomb oxidation test (RBOT).

• 한국신재생에너지학회:학술대회논문집
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• 2006.11a
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• pp.392-395
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• 2006

In this work, the reinforcing action of carbon blacks in rubber was investigated by SEM and UTM measurements which at low a testing of the surface and mechanical properties. In order to gain an insight into the different properties between carbon blacks before and after methane/propane decomposition, various composites were prepared with SBR synthetic rubber and different carbon blacks with four loading ratios. The results were analyzed with the aim of finding suitable conditions for decomposition reaction to cut down the net cost for hydrogen production through hydrocarbon decomposition.

• Proceedings of the KAIS Fall Conference
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• 2012.05a
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• pp.363-366
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• 2012

본 연구에서 NaOH, Acetic acid, Silane 처리는 천연섬유와 matrix간의 계면 결합에 불리하게 작용하는 wax, lignin, hemicellose 등을 제거하기 위한 방법 중의 하나이다. 이러한 화학적 처리에 따른 왕겨 분말의 기계적 특성 변화를 관찰하였다. Scaning electron microscopy(SEM)으로 관찰한 표면의 상태가 NaOH, Acetic acid, Silane 처리를 하였던 왕겨 분말이 처리를 하지 않았던 왕겨 분말보다 비교적 깨끗해지고, 크랙이 발생함을 확인하였다. 또한 전처리가 된 상태에서 PP와 20, 30, 40%의 비율로 복합재를 제조하여 Universal Testing Machine(UTM)으로 인장강도, 굴곡강도, 굴곡탄성률을 측정하였다. 또한, 왕겨의 입도 사이즈에 따라서 어떻게 변화되는지 알아보았다.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2014.05a
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• pp.108-109
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• 2014

The purpose of this study is to enhance durability of solidifying mat. solidifying mat excellent mechanical properties of geotextile. multi-layer coating system is applied to the mat and the chloride ions penetration resistance, chemical resistance, accelerated carbonation test were evaluated by testing the durability. Durability test results are as follows. chloride ions penetration resistance results are coated mat is approximately 70 % lower than plain. chemical resistance test results are coated mat no discoloration. accelerated carbonation test results are coated mat is approximately 90 % lower than the plain.

• The Magazine of the IEIE
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• v.29 no.3
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• pp.41-48
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• 2002

This paper presents a basic concept of lab-on-a-chip systems and their advantages in chemical and biological analyses. In addition, magnetic bead-based immunoassay on a microfluidic system is also presented as a typical example of lab-on-chip systems. Rapid and low volume immunoassays have been successfully achieved on the demonstrated lab-on-a-chip using magnetic beads, which are used as both immobilization surfaces and bio-molecule carriers. Total time required for an immunoassay was less than 20 minutes including sample incubation time, and sample volume wasted was less than $50{\mu}l$ during five repeated assays. Lab-on-a-chip is becoming a revolutionary tool for many different applications in chemical and biological analysis due to its fascinating advantages (fast and low cost) over conventional chemical or biological laboratories. Furthermore, simplicity of lab-on-a-chip systems will enable self-testing capability for patients or health consumers overcoming space limitation.

• 제어로봇시스템학회:학술대회논문집
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• 1992.10b
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• pp.170-175
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• 1992

A leak detection method for diagnosis of the leak position in a pipeline was developed using an estimation theory with the assumption that the measured flow rates and pressures are stochastic processes. A notch filter was designed using power spectral density analysis of measurements to reduce the effects of disturbances. The noise model dimension was determined by hypothesis testing and then recursive extended least square method was applied to estimate the leak position in real time. The proposed method was applied to an experimental system for evaluation of its performance.

• Applied Chemistry for Engineering
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• v.7 no.4
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• pp.633-638
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• 1996

The phenyl modified silicone polymer, 1,1-diphenyl-1-methyl-7-hydroxydodecamethylheptasiloxysilane, was synthesized to prepare the silicone polymer with good cold-proof and heart-proof properties. From the TGA analysis in the range of $100{\sim}800^{\circ}C$, the phenyl modified silicone polymer had good thermal properties than polydimethylsiloxane. And furthermore fluidity was maintained even below $0^{\circ}C$. Also, the silicone rubber blended with the phenyl modified silicone polymer had better mechanical properties than the silicone rubber.

• Membrane and Water Treatment
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• v.8 no.4
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• pp.369-380
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• 2017

Performance evaluation of four commercially available tubular membranes (AFC 80, AFC 30, PU 608, ES 404) was accomplished in self-assembled membrane testing unit. Effects of varying transmembrane pressure, feed concentration and anion type were investigated. Aqueous solutions of salts such as calcium chloride, calcium sulfate, tin chloride and tin sulfate were prepared for this study. It was noted that the investigated parameters e.g., pressure and concentration had significant effects on membrane's performance. Nevertheless, anion type effectively played its role in the rejection of salts since salt having SO4-2 anions had a better rejection than the salts containing Cl-1. It is observed that rejection was dominated by Donnon exclusion for strongly charged nanofiltration membranes whereas for weakly charged ultrafiltration membranes, size exclusion was the key mechanism to reject the ions.

• Nuclear Engineering and Technology
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• v.52 no.5
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• pp.1093-1097
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• 2020

A composite iodine sorbent was obtained in the form of porous polymer matrix with activated carbon particles impregnated with triethylenediamine deposited on its surface. A comparative assessment of the radioactive methyliodide capturing efficiency by the composite sorbent and a sample of industrial charcoal sorbent was conducted. It was shown that under the selected testing conditions, the hydraulic resistance of the composite sorbent is lower, and the sorption capacity is higher than that of the industrial charcoal sorbent. A method for comparing the effectiveness of iodine sorbents, based on the calculation of the ratio of the sorption capacity index to the minimum capacity index, needed for the required purification degree was proposed.

• Elastomers and Composites
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• v.57 no.2
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• pp.40-47
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• 2022

The effects of maleic-anhydride-grafted polypropylene (PP-g-MAH) and montmorillonite (MMT) on the wear resistance of polypropylene (PP) were investigated. The surface of MMT was modified with 3-aminopropyltriethoxysilane, and the interfacial interaction between PP and MMT was improved using PP-g-MAH. Fourier-transform infrared spectroscopy was used to confirm that silane was grafted on the surface of MMT. The Taber abrasion test and scanning electron microscopy were used to determine the wear resistance and observe the surface morphology of PP, respectively, after wear testing. Energy-dispersive X-ray spectroscopy was used to compare the effects of PP-g-MAH and silane modification of MMT on the dispersion of MMT. The results indicated that silane was successfully grafted onto the surface of MMT. Moreover, the wear resistance of PP was improved by the addition of MMT. The wear resistance of PP composites comprising silane-modified MMT and PP-g-MAH was higher than those of other PP composites. This was attributed to silane improving the interfacial interaction between MMT and PP.