• Journal of the korean academy of Pediatric Dentistry
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• v.49 no.4
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• pp.392-401
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• 2022

This study investigated the effects of silver diamine fluoride (SDF) and potassium iodide (KI) treatments on the acid resistance of dentin exposed to secondary caries. Sixteen bovine dentin specimens with artificially induced caries were assigned to the following four groups: untreated negative control, untreated positive control, SDF-treated (SDF), and SDF and KI-treated (SDFKI). Multispecies cariogenic biofilms containing Streptococcus mutans, Lactobacillus casei, and Candida albicans were cultured on the specimens for 28 days, except for the negative control group. Specimens from the negative control group were stored in phosphate-buffered saline for that period. After a cariogenic biofilm challenge, the degree of demineralization was evaluated using micro-computed tomography (micro-CT). As a result of data analysis using micro-CT, the demineralization depths of the negative control, positive control, SDF, and SDFKI groups were 149.0 ± 7 ㎛, 392.0 ± 11 ㎛, 206.0 ± 20 ㎛, and 230.0 ± 31 ㎛, respectively. The degree of demineralization was significantly reduced in the SDF and SDFKI groups compared with that in the untreated positive control group. There were no significant differences between the SDF and SDFKI groups. This study confirmed that SDF and SDFKI treatments increase the acid resistance of dentin to secondary caries. KI did not significantly affect the caries-arresting effect of the SDF.

• Korean Journal of Materials Research
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• v.5 no.4
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• pp.426-432
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• 1995

윤활제인 zinc stearate의 첨가량 (0~4wt%)을 변화시켜 U$O_{2}$분말의 겉보기밀도, 성형시의 분말입자간 마찰과 입자/다이벽 마찰간의 상관관계를 조사하였다. 소량의 윤활제 첨가시에는 U$O_{2}$분말입자간 박막의 윤활제 도포층이 형성되어 겉보기밀도가 증가한 반면 다량의 윤활제를 첨가한 경우에는 U$O_{2}$ 분말입자에 두꺼운 윤활제 도포층이 형성되고 미혼합된 윤활제가 존재하여 겉보기밀도는 감소하는 경향을 보였다. 윤활제를 첨가혼합한 상태에서 다이벽 윤활도포 유무에 따라 구한 U$O_{2}$ 성형체의 성형압력/성형밀도 자료로부터 분말입자간 마찰, 입자/다이벽 마찰 그리고 성형시 lubrication/inhibition등의 상대적 중요성을 조사하였다. 입자/다이벽 마찰에 의한 압력손실은 입자간 마찰에 의한 압력손실보다 크게 나타났다. 입자/다이벽 마찰에 의한 압력손실은 다이벽 윤활제 도포에 의해 최소화될 수 있지만 상대적으로 바람직하지 않은 성형시의 inhibition이 야기되는 것으로 나타났다.

• Proceedings of the Korean Society of Dyers and Finishers Conference
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• 2012.03a
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• pp.56-56
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• 2012

본 연구는 가정용 및 산업용 유해가스제거용 필터여재의 제조에 관한 것으로 핫멜트(hot-melt) 분사 시스템에 의한 다층구조의 부직포와 활성탄 등의 흡착물질로 구성되는 샌드위치 복합시트 및 필터여 재의 제조에 사용되는 구성재료의 최적화에 관한 연구이다. 스프레이 본딩 시스템에 의한 공정은 종래의 유해가스제거용 필터 미디어의 제조하는 방법인 활성탄과 바인더 역할을 하는 핫멜트 수지를 혼합하여 부직포 원단에 도포하여 활성탄을 부착시키는 공정에 비해 도포되는 핫멜트 수지의 양이 감소에 의한 생산비절감과 충분한 활성탄 도포에 의한 기능성 향상 등에 의해 유해가스 포집율을 높일 수 있으며 공정 이후 스프레이에 의해 도포된 핫멜트수지의 자연건조 방식에 의한, 열원이 불필요하며, 에너지가 절감되며, 속도 향상에 의한 생산성 향상, 분진발생 최소화로 인한 제조현장의 환경개선이 가능할 것으로 사료된다. 1차적으로 본 연구의 필터제조의 최적화를 위해서 스프레이 본딩시스템에 효율적으로 사용가능한 다양한 수지를 검토하였으며, 기존 외산 캐빈필터여재의 미세구조 및 성능특성, 다양한 활성탄의 흡착성능검토, 사용 가능한 여재의 특성분석을 통해 다층구조의 필터 여재에 사용 가능한 구성재료의 최적화에 중심을 두었다.

• KOREAN JOURNAL OF PACKAGING SCIENCE & TECHNOLOGY
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• v.14 no.1
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• pp.9-14
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• 2008

The effect of different porosity of onggis, Korean earthenware, on the fermentation of kochujang was investigated. The porosity was controlled with glazing treatment. Three kinds of onggis were made: one with no glazing treatment, one with outside glazing treatment, and one with both inside and outside glazing treatment. During 4 month fermentation of kochujang in porosity-controlled earthenwares, physical, chemical, microbiological, and sensory quality attributes were monitored. Higher protease activity and higher contents of amino nitrogen, free amino acids, and total neucleotide were observed in kochujang fermented in the onggi with outside glazing treatment, which might have resulted in better sensory quality. Onggi with medium porosity could be effective for fermentation of kochujang.

• Proceedings of the Korean Vacuum Society Conference
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• 2012.02a
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• pp.442-442
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• 2012

PEDOT[Poly(3,4-Ethylenedioxythiophene)]박막의 제작은 산화촉매제를 이용한 기상중합(Vapor Phase Polymerization)방법을 통해 최근 활발히 연구되어 지고 있다. 기상중합된 PEDOT박막의 특성은 박막의 중합의 정도와 성장 형상에 따라 그 특성이 크게 좌우된다. PEODT박막의 효율적인 중합에 있어 산화촉매제의 균일한 도포는 매우 중요하다. PEDOT의 효율적인 중합과 균일도포를 위해 산화촉매제에 DUDO와 PEG-PPG-PEG를 첨가한 혼합용액을 제작 VPP방법을 통해 PEDOT박막의 제작을 시도하였다. 그 결과 spin-coating 시 산화촉매 혼합용액의 균일한 도포가 관찰 되었으며 산화촉매제만 사용하여 제작된 박막에 비해 전도도와 막질이 향상된 PEDOT박막이 제작되었다. 이러한 결과는 산화촉매용액에 첨가된 PEG-PPG-PEG와 DUDO의 영향으로 PEG-PPG-PEG는 oxdiant용액의 균일 도포를 도왔으며 Inhibitor로 작용하는 DUDO는 PEDOT성장에 있어 불균일 결정성장을 억제하여 조밀한 PEDOT 박막 성장을 도운 것으로 생각된다. PEDOT 박막의 특성평가에는 Field Emission-Scanning Electron Microscopy, 4-Pointprobe, Optical microscopy 등이 사용되었다. 이러한 고전도도의 PEDOT박막을 OTFT의 전극소재로 사용한다면 OTFT소자의 성능 향상에있어 크게 기여 할 것으로 기대된다.

• Journal of the Microelectronics and Packaging Society
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• v.9 no.1
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• pp.49-52
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• 2002

This study demonstrated the feasibility of tape casting method to fabricate soda borosilicate glass-coated stainless steel electrostatic chucks(ESC) for low temperature semiconductor processes. Glass coating on the stainless steel substrate was 125 $\mu\textrm{m}$ thick. The adhesion of glass coating was found to be excellent such that it was able to withstand temperature cycling to over $300^{\circ}C$ without cracking and delamination. The electrostatic clamping pressure generally followed the theoretical voltage-squared curve except at elevated temperatures and high applied voltages. The deviations at elevated temperatures and high applied voltages are due to increased leakage current as the electrical resistivity of glass coating drops.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.14 no.9
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• pp.4467-4471
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• 2013

In this research, developed full-scan photoresist coating system(FPCS) can improve the efficiency of the photoresist coating system essential for spinner equipment in nano semiconductor manufacturing process. The devices developed in this research, which can be swiftly replaced in case abnormal state element changes or wafer manufacturing defect occurs, are anticipated to improve module yield as well as real-time monitoring on the state element in order to prevent the complex process defect due to the photoresist miss coating.

• Journal of Korean Society of Forest Science
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• v.105 no.4
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• pp.505-509
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• 2016

This study was conducted to examine the effectiveness of various dressing materials applied to tree wounds in Korea. Significantly higher wound closure rates than those of controls were found when thiophanatemethyl paste (Topsin Paste$^{(R)}$) was applied to Ginkgo biloba, Zelkova serrata, and Prunus yedoensis; lanolin to Z. serrata and P. yedoensis; and tebuconazole paste (Silvacur$^{(R)}$) to P. yedoensis. However, significantly lower wound closure rates than those of controls were found when petroleum jelly (Vaseline$^{(R)}$) was applied to G. biloba, Z. serrata, and P. yedoensis. It was noted that the wounds of Z. serrata and P. yedoensis treated with petroleum jelly expanded due to the death of cambium located at the edge of the wounds. Wound closure rates applied with adhesive - non-toxic to human body (Okong bond$^{(R)}$) were also significantly lower than those of controls in Z. serrata. Pinus densiflora showed no reaction to any experimental wound dressing because of resin secreted from the exposed cambium.

• Journal of the Korea Academia-Industrial cooperation Society
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• v.15 no.9
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• pp.5602-5609
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• 2014

This study examined the remineralization effect of CPP-ACFP according to the etching time and the frequency of application. A CPP-ACFP paste was formed from a combination of CPP-ACP paste and fluorine. The remineralization effect of CPP-ACFP was measured according to the etching time and the frequency of applications of CPP-ACFP. The microhardness of 64 teeth was measured as the sound sample and observed by scanning electron microscopy. As a result, the effect on remineralization of the enamel increased with increasing etching time and frequency of application. Therefore, a CPP-ACP paste combination to fluorine in the tooth mineral CPP-ACFP paste fluoride application can be supplied with the material-advisable enamel remineralization.

• Membrane Journal
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• v.11 no.2
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• pp.83-88
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• 2001

A methodology for enhancing the bond strength of a coating layer with a support has been established in preparing low-pressure reverse osmosis mO) hollow fiber which would experience shear badly in flowing feed un it. Prior to coating process, the support membrane, ultrafiltratiun polysulfone(PS) hollow fibers was pretreated with a reaction solution containing glutaraldehyde (GAl which has a good affinity to the suppurt membrane material as well as a reactivity to some of the cunstituents of cuating layer subsequently formed on the support by interfacial polymerization. Therefore, the reactant GA distributed unifonnly over the support layer through the pretreatment could provide a strong adhesive bond between the coating layer and the support, sticking fast to the support membrane through physical bond and, at the same time, connecting its functional group with the coating laycr by chemical bonding. Due to the strong adhesive bond, the resulting hollow fiber membrane showed an excellent long-tcnn stability in pcnneation.