• Proceedings of the Korean Society Of Semiconductor Equipment Technology
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• 2002.11a
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• pp.75-78
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• 2002

CNTs have been grown by the thermal CVD process in which $C_{2}H_{2}$ gas was deposited on the Fe - $Al(OH)_3$ mixture pretreated by mechanochemical treatment with a high energy mixer mill. As the duration time of grinding fer $Fe-(Al(OH)_3$ mixture by the mixer mill increased, amorphous $Al(OH)_3$ and more smaller Fe particles agglomerated into spheres. With unground and ground mixtures of $Fe-Al(OH)_3$, CNTs were grown at $700^{\circ}C$. As a result, CNTs grown on ground mixtures have more uniform diameter and morphology than those of unground mixture. The characterization of $Fe-Al(OH)_3$ mixture and as-grown CNTs were done by XRD, SEM and TEM.

• Bulletin of the Korean Chemical Society
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• v.34 no.2
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• pp.505-509
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• 2013

A low temperature ($65^{\circ}C$) thermal deposition process was developed for depositing a silver coating on thermally sensitive polymeric substrates. This low temperature deposition was achieved by chemical reduction of a silver alkylcarbamate complex with latent reducing agent. The effects of acetol as a latent reducing agent for the silver 2-ethylhexylcarbamate (Ag-EHCB) complex and their blend solutions were investigated in terms of reducing mechanism, and the size and shape of silver nanoparticles (Ag-NPs) as a function of reduced temperature and time, and PVP stabilizer concentration were determined. Low temperature deposition was achieved by combining chemical reduction with thermal heating at $65^{\circ}C$. A range of polymer film, sheet and molding product was coated with silver at thicknesses of 100 nm. The effect of process parameters and heat treatment on the properties of silver coatings was investigated.

• Proceedings of the Korean Fiber Society Conference
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• 2002.04a
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• pp.329-332
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• 2002

고밀도 폴리에틸렌(HDPE, High Density Polyethylene) 지오멤브레인은 독성 폐기물 처리시설에서 차수재로 광범위하게 이용되고 있으며, 열이나, 자외선, 그리고 산소와 화학약품에 노출되었을 때의 내구성이 장기성능에 커다란 영향을 미친다 어떤 원인에 의해서 지오멤브레인이 산화될 경우에는 지오멤브레인의 파괴가 가속화되어 구조 시스템의 안정성을 저하시키는 심각한 현상이 발생하게 된다. (중략)

• Proceedings of the KIPE Conference
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• 1997.07a
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• pp.266-268
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• 1997

High Voltage High Current Pulsed Electric Fields (HVHC-PEF) is a promising technology for the non-thermal pasteurization of foods and a sound complement or replacement to traditional thermal pasteurization, which inactivates bacteria and other microorganisms harmful to humans, but also degrades color, flavor, texture and nutrients. Foods can be pasteurized with pulsed electric fields at ambient or refrigerated temperatures for a short treatment time of seconds or less and the fresh-like quality of food is preserved. Although successful is laboratory tests, applying HVHC-PEF to food pasteurization on a large scale presents many unresolved engineering problems. In this paper the design considerations for 25kV 1kA class HVHC-PEF pasteurization equipment are anlyzed and experimental results are discussed.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.21 no.12
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• pp.23-32
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• 2020

This study investigated the thermal degradation and fading behavior of PTT dyed with vat dye and its dyeing ability. The PTT sample was dyed with vat dye using an acid treatment and pad-steam method to improve the dyeing performance. This method made dye particle nanosize and allowed it to penetrate the polymer material easily. The sample dyed using the pad-steam method showed level dyeing and enhanced dyeing affinity, compared to the batch-dyeing method. The degradation behavior of PTT dyed with vat dye after each heat and UV treatment was examined with the change in tensile strength or K/S value on the sample. The tensile strength and K/S values of the sample dyed with vat dye after the heat and UV treatment decreased with increasing temperature and exposure time. Although they showed high degradation under severe conditions, its rate constant was improved compared to the samples dyed with disperse dye. Consequently, acid treatment and the pad-steam method resulted in the introduction of vat dye on PTT. In addition, the PTT dyed with vat dye showed enhanced thermal and UV resistance because of their high molecular weight and chemical structure for stable adsorption behavior.

• Food Science of Animal Resources
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• v.37 no.1
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• pp.44-51
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• 2017

Heat treatment of milk aims to inhibit the growth of microbes, extend the shelf-life of products and improve the quality of the products. Heat treatment also leads to denaturation of whey protein and the formation of whey protein-casein polymer, which has negative effects on milk product. Hence the milk heat treatment conditions should be controlled in milk processing. In this study, the denaturation degree of whey protein and the combination degree of whey protein and casein when undergoing heat treatment were also determined by using the Native-PAGE and SDS-PAGE analysis. The results showed that the denaturation degree of whey protein and the combination degree of whey protein with casein extended with the increase of the heat-treated temperature and time. The effects of the heat-treated temperature and heat-treated time on the denaturation degree of whey protein and on the combination degree of whey protein and casein were well described using the quadratic regression equation. The analysis strategy used in this study reveals an intuitive and effective measure of the denaturation degree of whey protein, and the changes of milk protein under different heat treatment conditions efficiently and accurately in the dairy industry. It can be of great significance for dairy product proteins following processing treatments applied for dairy product manufacturing.

• Food Science and Preservation
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• v.20 no.2
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• pp.242-249
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• 2013

Thermal processing of (+)-catechin was carried out at $121^{\circ}C$ for different reaction times (1, 2, 3, 6, and 12 h). The reacted products, compounds (1) and (2), were isolated and quantified via HPLC analysis. The antioxidant properties of processed (+)-catechin and its isolated compounds for different reaction time was measured via radical scavenging assays using DPPH and $ABTS^+$ radicals. Additionally, the anti-obesity efficacy of the thermal treated (+)-catechin was evaluated via porcine pancreatic lipase assay. The reacted (+)-catechin for 3 h had a slightly higher antioxidant capacity than that the parent (+)-catechin. Products 1 and 2, which were isolated from the reacted mixture during 3 h, showed an antioxidant capacity, and these two compounds may be responsible for the antioxidant capacity of processed (+)-catechin. Simple thermal treatment of (+)-catechin can be used to produce (+)-epicatechin (1) and protocatechuic acid (2) with enhanced antioxidant and anti-adipogenic effects.

• Journal of Korean Neurosurgical Society
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• v.59 no.6
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• pp.559-563
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• 2016

Objective : Low back pain, caused intervertebral disc degeneration has been treated by thermal annuloplasty procedure, which is a non-surgical treatement. The theoretical backgrounds of the annuloplasty are thermal destruct of nociceptor and denaturization of collagen fiber to induce contraction, to shrink annulus and thus enhancing stability. This study is about temperature and its distribution during thermal annuloplasty using 1414 nm Nd : YAG laser. Methods : Thermal annuloplasty was performed on fresh human cadaveric lumbar spine with 20 intact intervertebral discs in a $37^{\circ}C$ circulating water bath using newly developed 1414 nm Nd : YAG laser. Five thermocouples were attached to different locations on the disc, and at the same time, temperature during annuloplasty was measured and analyzed. Results : Thermal probe's temperature was higher in locations closer to laser fiber tip and on lateral locations, rather than the in depth locations. In accordance with the laser fiber tip and the depth, temperatures above $45.0^{\circ}C$ was measured in 3.0 mm depth which trigger nociceptive ablation in 16 levels (80%), in accordance with the laser fiber end tip and laterality, every measurement had above $45.0^{\circ}C$, and also was measured temperature over $60.0^{\circ}C$, which can trigger collagen denaturation at 16 levels (80%). Conclusion : When thermal annuloplasty is needed in a selective lesion, annuloplasty using a 1414 nm Nd : YAG laser can be one of the treatment options.

• Journal of Physiology & Pathology in Korean Medicine
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• v.18 no.1
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• pp.226-229
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• 2004

We investigated the comparative effect with different frequency and duration time of electroacupuncture(EA) for suppression of pain. Inflammation was induced by an intraplantar injection of 1 % carrageenan into the right hind paw. Bilateral EA stimulation with 2 Hz, 15 Hz and 120 Hz were delivered at those acupoints corresponding to Zusanli and Sanyinjiao in man via the needles in carrageenan-injected rats. The paw and tail thermal hyperalgesia were measured in 30-minute intervals after carrageenan injection using hot plate and tail flick analgesia meter, respectively. The significant difference was found between the control and any of EA frequencies examined. Especially 2 Hz EA presented more effective inhibitory effects compared with other frequency of EA in tail flick latency. The hyperalgesia induced by carrageenan was strongly inhibited by 2 Hz EA from 5 min post and reached sufficient effects from 20 min post EA treatment. These results suggest that EA treatment might be a useful therapy for mitigation of inflammatory pain.

• Journal of Forest and Environmental Science
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• v.33 no.2
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• pp.154-159
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• 2017

Enzymatic treatment was conducted to hydrolyze pure cellulose nanofiber (PCNF), holocellulose nanofiber (HCNF), and lignocellulose nanofiber (LCNF) for 6, 24 and 72 hours and thus-obtained nanofibers (1, 3, 5, 10 wt%) were used to reinforce polyvinyl alcohol (PVA). Glucose production yield was increased by enzymatic hydrolysis. Tensile strength and elastic modulus of all PVA nanocomposite reinforced three nanofibers were improved by increasing enzymatic hydrolysis time of nanofibers and these values were higher in order of nanocomposite reinforced with PCNF>HCNF>LCNF. Furthermore, tensile properties of nanocomposite with PCNF were increased by nanofiber content. Thermal stability of PVA was improved by adding nanofibers and by increasing nanofiber content.