• Macromolecular Research
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• 제12권4호
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• pp.391-398
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• 2004

Thick-film photolithography is a new technology that combines lithography processes, such as exposure and development, with the conventional thick-film process applied to screen-printing. In this study, we developed a low-temperature cofireable silver paste applicable for thick-film processing to form fine lines using photolitho-graphic technologies. The optimum paste composition for forming fine lines was investigated. The effect of processing parameters, such as the exposing dose, had on the fine-line resolution was also investigated. As the result, we found that the type of polymer and monomer, the silver powder loading, and the amount of photoinitiator were the main factors affecting the resolution of the fine lines. The developed photoimageable silver paste was printed on a low-temperature cofireable green sheet, dried, exposed, developed in an aqueous process, laminated, and then fired. Our results demonstrate that thick-film fine lines having widths < 20 $\mu\textrm{m}$ can be obtained after cofiring.

• Current Photovoltaic Research
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• 제4권4호
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• pp.145-149
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• 2016

Characteristic of aluminum-silicon alloy paste which is applied on the rear side of PERC cell was investigated. The paste was made by aluminum-silicon alloy with eutectic composition to avoid the formation of void which is responsible for the degradation of the open-circuit voltage. Also, the glass frit component of the paste was changed to improve the adhesion of aluminum-silicon paste. We observed the formation of void and local back surface field between aluminum electrode and silicon base by SEM. The light IV, quantum efficiency and reflectance of the solar cells were characterized and compared for each paste.

• 수산해양교육연구
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• 제4권1호
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• pp.62-74
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• 1992

The effect of additional amounts of subsidiary materials on texture of fish meat paste were examined using Instron Universal Testing Machine to obtain fundamental data for steamed Alaska pollack meat paste showing good quality. The hardness revealed the good correlation with jelly strength among the six kinds of parameters of Instron texturometer. Products with higher hardness showed a better quality, but those with hardness higher than 16kg showed decreasing quality with increasing hardness. Predicting the quality of steamed Alaska pollack meat paste with various additional amounts of subsidiary materials as a function of hardness, H, the equation could be deduced as follows: H=11.56+0.54Xcs, H=12.22-0.23Xsp and H=11.65-7.13Xpp. The reasonable equations for predicting the quality of steamed Alaska pollack meat paste with various additional amounts of mixed subsidiary materials could be summarized as follows: H=11.57+0.53Xcs+0.44Xsp, H=11.97-1.83Xpp-0.17Xcs, and H=11.58+0.08Xpp-0.23Xsp.

• 마이크로전자및패키징학회지
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• 제21권4호
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• pp.83-89
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• 2014

Solder paste plays a crucial role as the widely used joining material in surface mount technology (SMT). The understanding of its behaviour and properties is essential to ensure the proper functioning of the electronic assemblies. The composition of the solder paste is known to be directly related to its rheological behaviour. This paper provides a brief overview of the solder paste behaviour of four different solder paste formulations, stencil printing processes, and techniques to characterize solder paste behaviour adequately. The solder pastes are based on the Sn-3.0Ag-0.5Cu alloy, are different in their particle size, metal content and flux system. The solder pastes are characterized in terms of solder particle size and shape as well as the rheological characterizations such as oscillatory sweep tests, viscosity, and creep recovery behaviour of pastes.

• 한국재료학회:학술대회논문집
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• 한국재료학회 1999년도 추계학술발표강연 및 논문개요집
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• pp.169-169
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• 1999

• 대한한의학원전학회지
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• 제29권2호
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• pp.177-185
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• 2016

Objectives : In pediatrics, one of the most difficult thing might be medication because infant or child cannot take medicine easily. In traditional medicine, Korean taffy or paste preparations sometimes prescribed. Xiao'eryaozhengzhijue was published by Qianyi in 1119 and is specialized for pediatrics text. So I tried to research paste preparations in Xiao'eryaozhengzhijue. Methods : I derived paste preparations from Xiao'eryaozhengzhijue ; paste preparations named on it, and used as paste preparations etc. Results : 1. There were external and internal application of paste preparations. 2. Diverse secondary materials were used for making paste preparations. 3. Several chief complains were recorded in Xiao'eryaozhengzhijue. Conclusions : Paste preparations are really useful way to disease of pediatrics because infant or child cannot take his or her medicine easily. Through the research, I could find out the facts that there are diverse shapes of paste preparations and usages of paste preparations in Xiao'eryaozhengzhijue.

• Advances in concrete construction
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• 제5권3호
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• pp.289-301
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• 2017

The synergistic interactions of supplementary cementitious materials (SCMs) with ordinary portland cement (OPC) in multi-blended systems could enhance the mechanical and durability properties of concrete and increase the amount of cement that can be replaced. In this study, the characteristics of the hydration products as well as paste microstructure of blended cement containing 20% coal fly ash, 10% rice hull ash and 10% sugar mill lime sludge in quaternary blended system was investigated. Portlandite content, hydration products, compressive strength, pore size distribution and microstructural architecture of hydrated blended cement pastes were examined. The quaternary blended cement paste showed lower compressive strength, reduced amount of Portlandite phases, and higher porosity compared to plain hardened cement paste. The interaction of SCMs with OPC influenced the hydration products, resulting to the formation of ettringite and monocarboaluminate phases. The blended cement paste also showed extensive calcium silicate hydrates and calcium aluminate silicate hydrates but unrefined compared to plain cement paste. In overall, the expected synergistic reaction was significantly hindered due to the low quality of supplementary cementitious materials used. Hence, pre-treatments of SCMs must be considered to enhance their reactivity as good quality SCMs can become limited in the future.

• 한국치위생학회지
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• 제18권4호
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• pp.423-432
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• 2018

Objectives: Calcium hydroxide, a root canal temporary sealer, has long been used and it has anti-bacterial and anti-inflammatory activity. To investigate the properties of a newly developed calcium hydroxide paste comprising silicon-substituted hydroxyapatite (Si-HA), we examined the anti-inflammatory activity of the new calcium hydroxide paste in RAW 264.7 macrophages stimulated by lipopolysaccharide (LPS), which causes infection of the root canal. Methods: The test materials, including Calcipex II as control group and the newly developed TRC paste, were extracted from cell culture media and then diluted for experiment. In LPS-stimulated RAW 264.7 cells, the cytotoxicity and nitric oxide (NO) production of test materials were measured by MTT assay and Griess reagents, respectively. Also, the expression of the inducible nitric oxide synthase (iNOS) was assessed by western blotting. Results: The IC50 values of Calcipex II and TRC paste were $17.6mg/m{\ell}$ and $13.5mg/m{\ell}$, respectively. The level of NO, increased by LPS, was dose-dependently inhibited more by TRC paste than Calcipex II treatment. In addition, iNOS expression was decreased by 71% and 92% at concentrations of $2mg/m{\ell}$ and $20mg/m{\ell}$ of TRC paste, respectively. Conclusions: We demonstrated that the Si-HA calcium hydroxide paste has a slightly improved anti-inflammatory property and further studies are needed before clinical recommendations are proposed.

• 열처리공학회지
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• 제19권4호
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• pp.219-224
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• 2006

Silver paste with low sintered temperature has been developed in order to apply electronic parts, such as bus electrode, address electrode in PDP (Plasma Display Panel) with large screen area. In this study, nano-sized silver particles with 10-30 nm were synthesized from silver nitrate ($AgNO_3$) solution by chemical reduction method and silver paste with low sintered temperature was prepared by mixing silver nanoparticles, conventional silver powder with the particle size 1.6 um and Pb-free frit. Conductive thick film from silver paste was fabricated by screen printing on alumina substrate. After firing at $540^{\circ}C$, the cross section and surface morphology of the thick films were analyzed by FE-SEM. Also, the sheet resistivity of the fired thick films was measured using the four-point technique.

• Composites Research
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• 제27권6호
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• pp.219-224
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• 2014

탄소나노튜브(CNT)의 물성은 고분자재료의 기계적, 전도성, 열적 물성을 향상시켜주기 때문에 많은 분야에서 소재개발을 진행 중이다. 본 연구에서는 사전에 CNT 10 wt% 페이스트를 제조하여 나노입자에 대한 분산도와 나노복합재료 생산성을 높일 수 있는 기초 재료를 제조하였다. 제조된 CNT 10 wt% 페이스트를 이용하여 손상 감지용 CNT 나노복합재료를 제조하여 균열에 대한 손상감지능과 균열 보강효과에 대한 영향을 연구하였다. CNT 10 wt% 페이스트를 이용하여 제조된 CNT 1 wt% 나노복합재는 일반 CNT 파우더를 이용하여 CNT 1 wt% 나노복합재료를 제조하였을 경우보다 인장과 굴곡물성이 높음을 확인하였다. CF30wt%/PP에 인위적인 균열을 제조하고, 균열부위에 CNT 나노복합재료를 보강하여 균열 및 파괴 발생 감지능을 균열크기에 따라 전기저항 측정법과 인장물성평가를 통해 분석하였다. CNT 나노복합재료를 균열 부위에 보강하여 CF30wt%/PP의 인장물성을 분석하였을 경우, 균열보강효과가 있었다. 균열크기가 증가함에 따라 CNT 나노복합재료의 보강효과의 증가되었다. 이는 CNT 나노복합재료와 CF30wt%/PP간의 접착면 증가로 균열전파를 지연하기 때문이다. CNT 나노복합재료의 손상감지능에 대해서는 전기저항 평가법으로 분석하였으며, 접착면에서의 분리로 인해 CNT 나노복합재료에 충격이 가해져 높은 전기저항 증가구간을 확인하였다. 손상감지용 CNT 나노복합재료의 균열방지효과와 손상감지에 대한 전기저항 평가법의 가능성을 확인하였다.