• Applied Microscopy
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• 제51권
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• pp.3.1-3.6
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• 2021

We examined the morphology of fertilized egg and ultrastructures of fertilized egg envelopes of dwarf rainbowfish (Melanotaenia praecox) belong to Melanotaeniidae using light and electron microscopes. The fertilized eggs were spherical with adhesive filament, transparent, demersal, and had a narrow perivitelline space and small oil droplets. The size of fertilized egg was 1.02 ± 0.18 mm (n = 30), and there were two kinds of adhesive filament on the fertilized eggs. The long and thick (diameter 12.22 ± 0.52 ㎛, n = 20) adhesive filaments were only at the area of animal pole, and short and thin (diameter 1.99 ± 0.23 ㎛, n = 20) adhesive filaments were around the long filaments. A micropyle was conical shaped with adhesive filament and located near the animal pole of egg. The outer surface of fertilized egg was rough side. Also, the total thickness of the fertilized egg envelope was about 7.46 ± 0.41 ㎛ (n = 20), the fertilized egg envelope consisted of two layers, an inner lamellae layer and an outer layer with high electron-density. And the inner layer was 8 layers. Collectively, these morphological characteristics and adhesive property of fertilized egg with adhesive filaments, and ultrastructures of micropyle, outer surface, and section of fertilized egg envelope are showed species specificity.

• 한국정밀공학회:학술대회논문집
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• 한국정밀공학회 2010년도 춘계학술대회 논문집
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• pp.725-726
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• 2010

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2002년도 하계학술대회 논문집
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• pp.32-35
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• 2002

The work focuses on the development of a Cu lead-frame with a single-sided adhesive tape for cost reduction and reliability improvement of LOC (lead on chip) package products, which are widely used for the plastic-encapsulation of memory chips. Most of memory chips are assembled by the LOC packaging process where the top surface of the chip is directly attached to the area of the lead-frame with a double-sided adhesive tape. However, since the lower adhesive layer of the double-sided adhesive tape reveals the disparity in the coefficient of thermal expansion from the silicon chip by more than 20 times, it often causes thermal displacement-induced damage of the IC pattern on the active chip surface during the reliability test. So, in order to solve these problems, in the resent work, the double-sided adhesive tape is replaced by a single-sided adhesive tape. The single-sided adhesive tape does net include the lower adhesive layer but instead, uses adhesive materials, which are filled in clear holes of the base film, just for the attachment of the lead-frame to the top surface of the memory chip. Since thermal expansion of the adhesive materials can be accommodated by the base film, memory product packaged using the lead-flame with the single-sided adhesive tape is shown to have much improved reliability. Author allied this invention to the Korea Patent Office for a patent (4-2000-00097-9).

• Restorative Dentistry and Endodontics
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• 제28권6호
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• pp.491-497
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• 2003

The purpose of this study was to evaluate the correlation between hybrid layer thickness and bond strength using confocal laser scanning microscope and microtensile bond strength test of two adhesive systems. The dentin surface of human molars. sectioned to remove the enamel from the occlusal surface. Either Scotchbond Multi-Purpose(3M Dental Product, St. Paul, MN, U.S.A) or Clearfil SE Bond (Kuraray, Osaka, Japan) was bonded to the surface. and covered with resin-composite. The resin-bonded teeth were serially sliced perpendicular to the adhesive interface to measure the hybrid layer thickness by confocal laser scanning microscope. The specimen were trimmed to give a bonded cross-sectional surface area of $1\textrm{mm}^2$, then the micro-tensile bone test was performed at a cross head speed of 1.0 mm/min. All fractured surfaces were also observed by stereomicroscope. There was no significant differences in bond strengths the materials(p>0.05). However. the hybrid layers of three-step dentin adhesive system, SM, had significantly thicker than self-etching adhesive system. CS(p<0.05). Pearson's correlation coefficient showed no correlation between hybrid layer thickness and bond strengths(p>0.05). Bond strengths of dentin adhesive systems were not dependent on the thickness of hybrid layer.

• Restorative Dentistry and Endodontics
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• 제46권2호
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• pp.30.1-30.13
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• 2021

Objectives: This study was conducted to compare the microleakage and characteristics of the resin-tooth tissue interface between self-etch and etch-and-rinse adhesive systems after 48 hours and 3 months. Materials and Methods: 40 extracted premolar teeth were randomly divided into 2 groups: 1-step self-etch adhesive system - Optibond^TM All-In-One, and 2-step etch-and-rinse adhesive system - Adper^TM Single Bond 2. Both groups were subjected to 500 thermocycles (5℃-55℃) before scanning electron microscope (SEM) analysis or microleakage trial at 48-hour and 3-month time periods. Results: SEM images showed the hybrid layer thickness, diameter, and length of resin tags of the self-etch adhesive (0.42 ± 0.14 ㎛; 1.49 ± 0.45 ㎛; 16.35 ± 14.26 ㎛) were smaller than those of the etch-and-rinse adhesive (4.39 ± 1.52 ㎛; 3.49 ± 1 ㎛; 52.81 ± 35.81 ㎛). In dentin, the microleakage scores of the 2 adhesives were not different in both time periods (48 hours/3 months). However, the microleakage score of etch-and-rinse adhesive increased significantly after 3 months (0.8 ± 0.63 and 1.9 ± 0.88, p < 0.05). Conclusions: The self-etch adhesive exhibited better long-term sealing ability in dentin when compared to that of the etch-and-rinse adhesive. The greater hybrid layer thickness and dimensions of resin tags did not guarantee reliable, long-lasting sealing in the bonding area.

• 대한소아치과학회지
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• 제33권3호
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• pp.377-387
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• 2006

본 연구는 자가산부식 접착시스템과 자가산부식 프라이머 접착시스템의 다층적용이 혼성층 및 adhesive layer의 형성 양상, 그리고 전단결합강도에 미치는 영향 등을 비교 평가하기 위하여 시행되었다. 영구 구치 140개의 치아를 근원심으로 분할하여 협면 혹은 설면의 상아질을 이용하였다. 각 접착시스템을 1회, 2회, 3회 도포, 그리고 1회 도포 후 광중합한 후 1회의 추가 도포한 군으로 분류하였다. 전단결합강도와 혼성층 및 adhesive layer 두께를 측정하여 분석한 결과 다음과 같은 결론을 얻었다. 1. 모든 접착제에서 도포횟수가 증가함에 따라 adhesive layer의 두께가 증가하였으며 (p<0.05), Adpor Prompt L-Pop과 Xeno III에서는 자가산부식 프라이머 시스템에서보다 작게 나타났다(p<0.05). 2. Adpor Prompt L-Pop에서 혼성층은 도포횟수에 따라 혼성층의 두께도 증가하였다(p<0.05). 3. Unifill Bond와 Clearfill SE Bond의 전단결합강도는 Scotchbond Multi-Purpose Plus와 Adpor Prompt L-Pop에서보다 높게 나타났으며 (p<0.05), Xeno III와는 유사하였다. 4. Adpor Prompt L-Pop은 접착제의 도포횟수가 증가함에 따라 전단결합강도는 유의하게 증가되었으며(p<0.05), AdheSE에서는 3회 도포한 경우 전단결합강도가 감소하는 경향을 보였다(p>0.05). 5. Adpor Prompt L-Pop과 Xeno III에서 첫 층을 중합한 후 두 번째 층을 추가 도포한 경우 전단결합강도는 감소하였다(p<0.05).

• Journal of Pharmaceutical Investigation
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• 제25권4호
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• pp.339-345
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• 1995

For the effective treatment of aphthous stomatitis, the matrix type mucoadhesive patches containing triamcinolone acetonide have been formulated. The drug layer was obtained by drying the polymer gel which was prepared with carbomer 934P, ammoniomethacrylate copolymer, titanium dioxide and polyethylene glycol 400. The effects of the content of additives on physical characteristics of the polymer gel and the drug layer were evaluated. The addition of carbomer increased the yield point and the zero-shear viscosity of polymer gel as well as the thickness, the water absorption ratio, the adhesive time and $T_{50%}$ of drug layer. The adhesive time and the water absorption ratio of drug layer were also improved by the addition of ammoniomethacrylate copolymer, but the addition of titanium dioxide had decreased the zero-shear viscosity of polymer gel and the adhesive time of drug layer.

• Composites Research
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• 제22권2호
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• pp.14-17
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• 2009

접착제에 의한 접합기술은 다양한 목적과 환경에서 널리 사용되는 방법이다. 그 중 우레탄 접착제는 액화천연가스 운반선과 같이 극저온에서 사용되는 환경에서의 접착에 사용되고 있다. 현장 적용에 있어, 본 접착제를 사용시 경화된 접착제 층의 기공들이 발생하게 된다. 본 연구에서는 우레탄 접착제와 Triplex 복합재료 접착에 있어 인공적으로 기공을 제작 삽입 후 전단응력 (Single Lap Shear) 시험을 실시하여 그 영향을 검토하였다. 실험 결과 접착력은 본 시험에서 적용한 기공의 크기 및 위치에 영향을 받지 않는다는 것을 확인하였다.

• Journal of Welding and Joining
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• 제10권4호
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• pp.181-189
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• 1992

The purpose of this investigation is to examine the effects of the strengthening treatments on the mechanical properties of the flame-sprayed titania ceramic coating layer. The strengthening treatments for flame sprayed specimens were carried out in 12 different conditions in vaccum furance. The mechanical properties such as microhardness, thermal shock resistance, adhesive strength and erosion resistance were tested for the sprayed specimens after strengthening treatments. And it was clear that the mechanical properties of coating layer were much improved by the strengthening treatments. The results obtained are summarized as follows; 1. It was shown that the metallurgical bond was formed between substrate and coating layer by the strengthening treatments and that thermal shock resistance and adhesive strength were remarkably raised. 2. Microhardness of coating lay was considerably increased by the strengthening treatments. 3. Erosion resistance and porosity of coating layer were slightly improved by the strengthening treatments.

• 대한기계학회논문집
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• 제16권4호
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• pp.667-674
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• 1992

본 연구에서는 복합재료의 접착이음에 대한 강도 평가법을 확립하기 위한 기 초연구로써 접착이음의 가장기본적인 형태의 하나인 겹치기 이음(single-lap joint: SLJ)에 대한 응력해석과 정적 및 피로 강도시험을 실시하고, 종래의 강도평가법의 문 제점을 파악.검토하고 정량적이고 통일적인 접착이음의 강도평가법의 확립 및 설계 기 준의 설정에 대한 새로운 방향을 모색 하고저 한다.