• 대한한방내과학회지
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• 제39권4호
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• pp.637-644
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• 2018

Objectives: In this study, the tongue features of patients with functional dyspepsia (FD) were compared with those of healthy controls. Methods: This prospective, case-control study was conducted on patients with FD and controls recruited at a single center. After screening, the subjects were allocated to the patient or control groups (patients=42, controls=40). Tongue images were acquired using a computerized tongue image acquisition system (CTIS). An independent t-test was conducted to compare the measurements from patients and controls. Binary logistic regression was performed to determine significant differences between the two groups after adjusting for age and sex. Results: The CIE $a^*$ color value in the tongue coating area was significantly lower in the patients with FD than in the controls (p=0.001). The tongue coating ratios were also significantly higher in the FD group than in the control group (p=0.003). We found that the CIE $a^*$ color value in the tongue coating area and the tongue coating ratios were significant predictive factors in both groups, based on binary regression analysis (p=0.016, 0.044, respectively). Conclusions: This study found that FD was significantly associated with CIE $a^*$ color value in the tongue coating area and tongue coating ratios. We suggest that these factors could be used as objective indicators of FD.

• 한국분말재료학회지
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• 제15권2호
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• pp.101-106
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• 2008

The objective of the present study is to investigate the increase in the functional characteristics of a substrate by the formation of a thin coating layer. Thin coating layers of $Ti_5Si_3$ have high potential because $Ti_5Si_3$ exhibits high hardness. Shock induced reaction synthesis is an attractive fabrication technique to synthesize uniform coating layer by controlling the shock wave. Ti and Si powders to form $Ti_5Si_3$ using shock induced reaction synthesis, were mixed using high-energy ball mill into small scale. The positive effect of this technique is highly functional coating layer on the substrate due to ultra fine substructure, which improves the bonding strength. These materials are in great demand as heat resisting, structural and corrosion resistant materials. Thin $Ti_5Si_3$ coating layer was successfully recovered and showed high Vickers' hardness (Hv=1183). Characterization studies on microstructure revealed a fairly uniform distribution of powders with good interfacial integrity between the powders and the substrate.

• 한국표면공학회:학술대회논문집
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• 한국표면공학회 2001년도 춘계학술발표회 초록집
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• pp.63-64
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• 2001

• 한국산학기술학회논문지
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• 제18권10호
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• pp.771-776
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• 2017

모바일 디스플레이 및 태양전지의 커버글라스에는 반사방지 코팅 및 셀프클리닝과 같은 기능성 코팅이 필요하다. 최근 들어 나방 눈 또는 연꽃 잎과 같은 자연의 기능성 표면을 모사하여 공학적으로 응용하고자하는 많은 연구가 수행되었다. 특히 실리카 나노입자를 이용한 반사방지 기능성 코팅은 빛의 투과를 증가시키며, $TiO_2$ 광촉매 코팅은 셀프클리닝 기능성 필름에 적용되어왔다. 본 연구에서는 $SiO_2/TiO_2$ 나노입자의 박막 코팅에 의한 투명 발수 반사방지 코팅을 sol-gel 공정과 dip-coating 공정으로 글라스 기판 위에 제조하였다. 기능성 코팅의 표면형상 의존성을 원자힘현미경, 접촉각 측정 및 UV-visible 분광광도계 분석으로 조사하였다. 그 결과 $TiO_2$ 나노입자의 코팅은 가시광선 영역에서 투과율을 저하시키지 않고 기판인 슬라이드 글라스와 비슷한 수준의 높은 평균 광 투과율을 나타내었다. 또한 7nm $SiO_2$/7nm $TiO_2$ 나노입자의 이중층 기능성 코팅은 접촉각 $110^{\circ}$의 투명 발수 표면 특성을 나타내었으며, 가시광선 영역에서 기판인 슬라이드 글라스 보다 2.3% 높은 평균 투과율의 향상을 나타내었다.

• 한국전기전자재료학회논문지
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• 제29권4호
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• pp.215-217
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• 2016

For the improvement of the anti-pollution properties of porcelain electrical insulators, in this study, we have applied the functional film to the surface of insulator. The functional films were coated on the ceramic substrates which components were like the porcelain electrical insulator. The coating material was applied to ceramic substrate by spray coating method and then the film was cured at around $300^{\circ}C$ for 10 minutes with different gas ambient, such as $O_2$, $N_2$, and only vacuum. We have measured the contact angle of the coated surface, and obtained the lowest angle ($8.9^{\circ}$) and a strong hydrophilic property at vacuum condition. The anti-pollution properties were measured, revealing that as the contact angle decreased, the anti-pollution properties improved. The mechanical hardness and adhesion were both excellent regardless of the annealing ambient.

• 한국입자에어로졸학회지
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• 제9권3호
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• pp.127-132
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• 2013

Recently, Aerosol Deposition method has attracted considerable attention because of its advantages to produce ceramic coatings on various substrates at room temperature. This method is strongly dependent on the raw powder, which should have high mobility with carrier gas and moderate mechanical strength to be crushed onto the substrate. In this report, the effects of the ceramic granules' compressive strength on the ceramic coating formation are discussed. The ceramic granules were prepared by spray-drying method and heat treated at various temperatures. It was found that at the moderate mechanical strength of ceramic granules gave more effective film formation behavior during Aerosol Deposition method.

• 한국식품영양과학회지
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• 제42권3호
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• pp.415-420
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• 2013

쌀의 기능성 소재화 및 새로운 용도 개발 연구의 일환으로, 제2형 당뇨환자의 혈당을 조절할 수 있는 인슐린 기능 개선 소재로 알려져 있는 cyclo histidine-proline(CHP) 함유 대두가수분해물(SHC)을 쌀에 함유시켜 신규 기능성 쌀을 개발하고자 하였다. 이를 위해 흡수 및 분무 코팅에 의해 쌀의 가공 중 첨가 기능성 성분인 CHP 함유된 대두가수분해물의 소실을 억제하는 기능성 성분 강화 코팅 쌀의 제조공정을 검토하였다. 흡수 코팅법은 CHP 함유 대두가수분해물의 농도 증가에 따라 흡수저해가 일어나 흡수율이 낮게 나타나므로 적합하지 못하였다. 반면 methylcellulose 폴리머를 사용한 분무 코팅에 의하여 제조된 코팅 쌀은 다소의 균열 발생 및 미황색화가 관찰되었으나 외관 형태의 큰 변화는 관찰되지 않았다. 특히, 수화양상 및 수화속도가 원료 쌀에 비하여 높게 나타났으며, 코팅과정 중의 건조에 의한 호화 등은 관찰되지 않았다. 따라서 5%(w/v)의 CHP 함유 대두가수분해물을 함유한 1%(w/v) methylcellulose 폴리머를 보호제로 사용하여 분무 코팅한 후 건조하여 CHP 함유 대두가수분해물을 기능성 성분으로 하는 기능성 코팅 쌀을 제조하는 공정을 확립하였다.

• 한국재료학회지
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• 제20권11호
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• pp.570-574
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• 2010

A diamond-like carbon (DLC) film deposited on a WC disk was investigated to improve disk wear resistance for injection molding of zirconia optical ferrule. The deposition of DLC films was performed using the filtered vacuum arc ion plating (FV-AIP) system with a graphite target. The coating processing was controlled with different deposition times and the other conditions for coating, such as input power, working pressure, substrate temperature, gas flow, and bias voltage, were fixed. The coating layers of DLC were characterized using FE-SEM, AFM, and Raman spectrometry; the mechanical properties were investigated with a scratch tester and a nano-indenter. The friction coefficient of the DLC coated on the WC was obtained using a pin-on-disk, according to the ASTM G163-99. The thickness of DLC films coated for 20 min. and 60 min. was about 750 nm and 300 nm, respectively. The surface roughness of DLC films coated for 60 min. was 5.9 nm. The Raman spectrum revealed that the G peak of DLC film was composed of $sp^3$ amorphous carbon bonds. The critical load (Lc) of DLC film obtained with the scratch tester was 14.6 N. The hardness and elastic modulus of DLC measured with the nano-indenter were 36.9 GPa and 585.5 GPa, respectively. The friction coefficient of DLC coated on WC decreased from 0.2 to 0.01. The wear property of DLC coated on WC was enhanced by a factor of 20.

• 한국인쇄학회지
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• 제15권2호
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• pp.25-40
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• 1997

This research was carried out to investigated the effect of base paper and latex binder on printability and obtical properties of coated paper. Especially, it examined the effect of th pH of vase paper surface and functional groups of latices on the interactions between coating color components and on the structure of coated layer. It was found that the behavior of coating color containing amphoeric latex depends on the pH in the boundary region between coating color and base paper. Thus, the coating color formulated with amphoteric latex formed bulky coating layer by inducing stronger interaction between paper surface and coating components than the coating color with anionic latex. The coated paper with amphoteric latex showed better optical properties (i.e.gloss and optical) and printability (i.e. ink receptivity, wet ink receptivity, and ink set off) than the conventional anionic latex in the acidic and alkaline paper. However, dry pick strength of the coated paper was less decreased. This result indicated that amphoteric latex could also be applied practically to the alkaline paper.

• 한국식품영양학회지
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• 제23권4호
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• pp.600-606
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• 2010

The objective of this study was to develop functional rice coated with yacon roots extracts and to evaluate the antioxidant properties and physiological activity of rice coated with yacon extract. The washed rice was coated by spraying yacon extract at 10, 20, 30, and $40^{\circ}Brix$ and dried at room temperature. The moisture contents, color changes, antioxidant properties as total polyphenolics and DPPH radical scavenging activity and instrumental texture property and sensory evaluation change in the yacon root extracts coated rice and uncoated cooked rice were observed during 3 days of storage. Increasing the coating concentration was associated with lower color values(L value) and moisture contents. Total phenolics and DPPH radical scavenging properties generally increased in the cooked rice coated with yacon root extract more than the control (non-coated rice). However, D-20($20^{\circ}Brix$ of the yacon root concentration) resulted in better textural properties and sensory overall acceptability in cooked rice on 0 and 3 storage days. It was concluded that the optimum coating ration of rice and added functional yacon rice were $20^{\circ}Brix$ and 7% respectively, in proportion to the total weight of raw rice.