• 대한기계학회:학술대회논문집
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• 대한기계학회 2007년도 춘계학술대회A
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• pp.1798-1802
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• 2007

Adhesion strength of single layer ceramic capacitor sheet was measured using a peel testing system developed in this study. The peel test specimens with various dimensions were prepared from the ceramic sheet cast on the PET film. In peel test, the sheet specimen was adhered on the glass jig floating on the liquid media, which was designed to minimize the friction, and the specimen was then pulled up by micro-actuator. During the separation of the sheet from the PET film, peel force was measured. To normalize the testing condition, 3 different widths of the specimen were selected: 5, 10 and 20 mm. was used Furthermore, testing speed effect was investigated in this study. From the resullts using various testing conditions, the standard method for the peel strength testing may be suggested. Based on the testing condition, effect of peel angle on the strength was experimentally examined. It was found that the adhesive strength for the ceramic sheet is nearly identical, irrespective of the specimen width ranged from 5 to 20 mm, while the adhesive strength was increased with increasing testing speed. Furthermore, the strength was shown to be dependent on the peel angle.

• Current Photovoltaic Research
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• 제9권2호
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• pp.31-35
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• 2021

Shingled module shows high ratio active area per total area due to more efficient packing without inactive space between cells. The module is fabricated by connecting the pre-cut cells into the string using electrically conductive adhesives (ECA). ECAs are used for electric and structural connections to fabricate the shingled modules. In this work, we investigated a correlation between ECA peel strength and the efficiency of pre-cut 5 cells module which are fabricated according to ECA interconnection conditions. The curing conditions are varied to determine whether ECA interconnection properties can affect module properties. As a result of the peel test, the highest peel strength was 1.27 N/mm in the condition of 170℃, the lowest peel strength was 0.89 N/mm in the condition of 130℃. The efficiency was almost constant regardless of the curing conditions at an average of 20%. However, the standard deviation of the fill factor increased as the adhesive strength decreased.

• 구강회복응용과학지
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• 제16권2호
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• pp.123-132
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• 2000

The field of maxillofacial prosthetics is concerned with the prosthetic reconstruction of missing head and neck tissue. Currently, facial prostheses are usually applied in cases of defects caused by the surgical removal of tumors or congenital defects. While silicone has been most widely used for the reconstruction of missing maxillofacial defects, it does not have ideal physical properties. Therefore, bonding a thin polyurethane sheet to silicone prostheses was recommended. In this case skin adhesives were used for the retention of maxillofacial prostheses. But retention of devices has always been problematic. The contributions of implants can be made to solve these problems. Implants have reduced the need for adhesive use, simplifying cleaning procedures and thus extending the life of the prostheses. For implant-retained prostheses, retentive matrix is necessary to hold attachments and/or magnets. The retentive matrix is usually fabricated with autopolymerizing acrylic resin or visible light- polymerized resin. The purpose of this study was to compare the adhesion-in-peel force of silicone adhesive to autopolymerizing acrylic resin and polyurethane sheet with two different surface textures : pumice polish only or retention groove, and three surface primers : Dow corning 1205 primer or Dow corning S-2260 primer or FactorII A-304 primer, and two polymerization methods : room temperature or dry heat oven. The t-peel bond strength of specimens was determined as described in ASTM Standard D1876-72. The results were statistically analyzed using the ANOVA test, multiple range test and t-test The results were as follows. 1. The t-peel bond strength of A-304 primer was the highest and statistically higher than that of S-2260(p<0.05). 2. The t-peel bond strength of specimens with retention groove was statistically higher than that of specimens polished with pumice(p<0.05). 3. The t-peel bond strength of specimens polymerized in dry heat oven was statistically higher than that of specimens in room temperature(p<0.01).

• 대한기계학회논문집A
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• 제33권5호
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• pp.474-481
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• 2009

Fracture models and criteria of adhesive with two parameters, namely $G_C$ and ${\sigma}_{max}$, have been developed to describe the fracture process of adhesive joints. Cohesive zone model(CZM) is a representative two parameter failure criteria approach. In CZM, ${\sigma}_{max}$ is a critical, limiting maximum value of the stress in the damage zone ahead of the crack and is assumed to have some physical significance in adhesive failure. Based on CZM and finite element analysis method, the relationship between fracture load and adhesive properties, as $G_{IC)$ and $({\sigma}_{max})_I$, was investigated in adhesively bonded joint tensile test and T-peel test. The two parameters in tensile mode loading were evaluated by using the relationship. The value of $G_{\IC}$ evaluated by proposed method showed close agreement with analytical solution for tapered double cantilever beam(TDCB) test which proposed in an ASTM standard.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2005년도 춘계 학술기술논문발표대회 논문집
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• pp.173-178
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• 2005

The tile construction methods for existing have been used materials within limit which adhesion by wet method in masonry wall and concrete structure. These existing adhesive tech can caused many problems in construction of large and reform tile, after that it can be happened loose scale, peel off, falling off tile by heat and vibration or impact. In according to, this study is to test tile for bond stability, adhesive property by impact, vibration. low property by heat and then, we have the results as below; (1) The tile adhesive stability can be effected as adhesive area between bond agent and tile, adhesive area can more wide and press enough to ensure property. (2) Existing adhesive strength and standard relative tile construction is limited to adjust performance tile on the concrete and masonry wall. In summary, It is necessary to establish standard of performance and test method to ensure tile adhesive salability in dry wall.

• Transactions on Electrical and Electronic Materials
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• 제14권3호
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• pp.133-138
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• 2013

Acrylonitrile-butadiene-styrene (ABS) plastic is a polymer material extensively used in electrical and electronic applications. Nickel (Ni) thin film was deposited on ABS by electroless plating, after its surface was treated and modified with atmospheric plasma generated by means of dielectric barrier discharges (DBDs) in air. The method in this study was developed as a pre-treatment for electroless plating using DBDs, and is a dry process featuring fewer processing steps and more environmentally friendliness than the chemical method. After ABS surfaces were modified, surface morphologies were observed using a scanning electron microscope (SEM) to check for any physical changes of the surfaces. Cross-sectional SEM images were taken to observe the binding characteristics between metallic films and ABS after metal plating. According to the SEM images, the depths of ABS by plasma are shallow compared to those modified by chemically treatment. The static contact angles were measured with deionized (DI) water droplets on the modified surfaces in order to observe for any changes in chemical activities and wettability. The surfaces modified by plasma showed smaller contact angles, and their modified states lasted longer than those modified by chemical etching. Adhesion strengths were measured using 3M tape (3M 810D standard) and by 90° peel-off tests. The peel-off test revealed the stronger adhesion of the Ni films on the plasma-modified surfaces than on the chemically modified surfaces. Thermal shock test was performed by changing the temperature drastically to see if any detachment of Ni film from ABS would occur due to the differences in thermal expansion coefficients between them. Only for the plasma-treated samples showed no separation of the Ni films from the ABS surfaces in tests. The adhesion strengths of metallic films on the ABS processed by the method developed in this study are better than those of the chemically processed films.

• 소성∙가공
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• 제27권5호
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• pp.267-275
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• 2018

The clad sheet material is produced by a roll-bonding process of one or more materials with different properties. Good formability of clad sheet material is an essential property in to deform a clad metal sheet into a part or component. Performance of the clad sheet material largely depends on interfacial bond strength between different materials. In this study, interfacial bond strength of STS/Al clad sheet was analyzed by varying experimental parameters using a blanking process. Experimental parameters are the punching speed, clearance, and stacking order of plate materials. In addition, blanking test results were compared with bond strengths measured by the T-peel test, that analyzes interface bonding strength of the standard clad sheet. The blanking process was analyzed by the finite element method under the sticking condition of interface of different materials, and experimental results and analysis results were compared.

• 한국식품저장유통학회지
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• 제7권3호
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• pp.331-336
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• 2000

식용유지에 대한 고구마 추출물의 항산화능을 검토하기 위하여 linoleic acid와 돈지에 70% methanol 고구마 추출물을 가하여 $60^{\circ}C$에서 저장하면서 POV를 측정하여 항산화능을 비교하였으며, 고구마 항산화 성분을 추출하여 HPLC를 이용하여 정성, 정량하여 다음과 같은 결과를 얻었다. 70% methanol 고구마 추출물의 항산화능은 목포18이 율미보다, 껍질부위가 속부위보다 강한 항산화활성을 나타내었다. 고구마 페놀화합물 3개 분획 중 가장 강한 항산화능을 보인 것은 free phenolic acids(fraction-I)층 분획이었다. 껍질부위의 free phenolic acids 항산화능은 속부위보다 강하였고 율미가 목포18보다 항산화능이 높았다. 고구마 항산화 성분인 페놀화합물을 HPLC로 분석한 결과 caffeic acid와 chlorogenic acid이었고, 함량은 caffeic acid는 율미껍질에 68.4mg%, 율미속에 2.8mg%, 목포18껍질에 47.2mg%, 목포18속에 4.6mg% 함유되어 있었으며, chlorogenic acid는 각각 67.4mg%, 1mg%, 92.6mg%, 1.2mg% 이었다. Linoleic acid-emulsion에 대한 항산화능은 caffeic acid가 chlorogenic acid보다 높게 나타났다.

• 혜화의학회지
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• 제13권2호
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• pp.187-196
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• 2004

Now many sustitution and false articles is used in korea instead of shanyao. To use shanyao correctly, we will make a quilitative certificational plan of shanyao to investigate all of lieraturea, records and documents. And we could reach conclusions as folloews. 1) Source About a source of shanyao, though korea and china has a each other source, we think there is no problem in use of both. 2) Process In our country producing shanyao as medical use is a 'duanma', we can divide into peeling and non-peeling, drying at bulks and at briquets, steaming shanyao and fresh shanyao. Regardless of existence for peeling and steaming, a distributing shanyao is received a proper judgment. Like this result was expressed by insufficiency of standards about medical components or indicating components. We detected a reminding S02 more than 10 ppm. And this expresses that there ia a problum at a drying method. To suggest proper processing methods, a standard of quility will have to be made which the existence of peeling, difference of quility between 'changma' and 'duanma', drying method and exudation test with cutted thickness are adaptable. Besides, 'maoshanyao' and 'guangshanyao' of china is processed by various methods which decrease a medical effect such as too much soaking shanyao in water, steaming with a sulfur, too much peeling, So we must process shanyao like the next methods. (1) When harvesting, dig deeply not to cut off roots. (2) Not to peel, wash shanyao in a washing machine. (3) Dry to 50-60% degree at sunny place or drying machine. (4) To be easy for drying and exudation, cut off a thick piece with 5 mm (5) Dry perfectly at ding machine. 3) Quality3) Quality (1) Functional standards It is not Proper that 'guangshanyao' is used in china because it has a problem with quility on process of working, If they did not soak shanyao in water or heat with steam, it is the real situation that they cannot cutt off shanyao evenly. In conclusion, shanyao must be heavy, powdery with a perfectly non-peeling surface, section surface is yellow-white color, unequal and has no holes. (2) Physicochemical standards It is the real situation that we can not distinguish into quility of shanyao with established test because various workings which decrease medical effects is used. Therefore we suggest a testing standard of S02 which is used in bleaching. And testing standards relatived with decrease of medical effects must be established at once. It must that Dry on loss is less than 14.0%, content of ash is less than 6.0%. Content of acid-nonsoluble ash is less than 0.5%. Contens of heavy metal has to detect less than 30 ppm and there is no reminding agricultural medince.