• 한국세라믹학회지
• /
• 제46권4호
• /
• pp.365-371
• /
• 2009

It is well known that the properties of concrete such as the compressive strength, water permeability, water tightness and durability are affected by micro-structure in hardened cement paste. Especially, for durability of concrete, watertightness of cementitious materials is the most critical property among various properties. Recently, many types of materials as organic and/or inorganic materials are used for watertightness of concrete. In this study, The effect of Stearic Acid at $0.5\;wt%{\sim}3.0\;wt%$ adding ratios on the hydration and watertightness property of cement were investigated. And we also discussed the changing of microstructure in hardened cement paste by addition of Stearic Acid. Cement paste with Stearic Acid showed improvement of watertightness by reducing of cement total pore volume and decomposition of Stearic Acid.

• 한국식품영양과학회지
• /
• 제27권1호
• /
• pp.10-15
• /
• 1998

In order to establish the quality standard of commercial soybean paste, pH, color, moisture, crude protein, isoflavone, free amino acid and organic acid contents of the fermented soybean food in both traditional and commercial products were analyzed. The crude protein contents were from 5.0 to 11.9% in commercial soybean pasted of Samjang and traditional soybean paste of Chungugjang, and the latter showed higher value than those of the former. The contents of isoflavones in commercial soybean paste were less than those of traditional soybean paste. Total contents of free amino acids were distributed from 301 to 4,602mg%, respectively, in which Chungugjang showed the smallest value of 301mg% and the traditional soybean paste showed the most abundant one of 4,602mg%. The ratio of glutamic acid to total free amino acids were 15.9% and 30.1% in traditional soybean paste and commercial soybean paste, respectively. The major organic acid both commercial soybean paste and Samjang was citric acid containing 109.9~196.5mg%. On the other hand, that of traditional soybean paste and Chungugjang was oxalic acid containing 82.8~130.1mg%. This results might be caused by the differences of brewed periods, microflora, processing methods and used raw materials.

• 한국재료학회지
• /
• 제20권1호
• /
• pp.19-24
• /
• 2010

The current study examined Ag migration from the Ag paste bump in the SABiT technology-applied PCB. A series of experiments were performed to measure the existence/non-existence of Ag in the insulating prepreg region. The average grain size of Ag paste was 30 nm according to X-ray diffraction (XRD) measurement. Conventional XRD showed limitations in finding a small amount of Ag in the prepreg region. The surface morphology and cross section view in the Cu line-Ag paste bump-Cu line structure were observed using a field emission scanning electron microscope (FE-SEM). The amount of Ag as a function of distance from the edge of Ag paste bump was obtained by FE-SEM with energy dispersive spectroscopy (EDS). We used an electron probe micro analyzer (EPMA) to improve the detecting resolution of Ag content and achieved the Ag distribution function as a function of the distance from the edge of the Ag paste bump. The same method with EPMA was applied for Cu filled via instead of Ag paste bump. We compared the distribution function of Ag and Cu, obtained from EPMA, and concluded that there was no considerable Ag migration effect for the SABiT technology-applied printed circuit board (PCB).

• 수산경영론집
• /
• 제43권2호
• /
• pp.15-26
• /
• 2012

This study aimed to examine the establishment of the fish-paste processing industrial cluster in Busan. In order to successfully promote the fish-paste processing industrial cluster in Busan, first of all, it is required to implement various fish-paste processing related infra-structures and foundations. In addition to this, the agreements among fish-paste processing related organizations and businesses are inevitable to secure plans of inter-working with fisheries policies, to make efficient conditions for the stable supply of raw materials, and to pursue various supports from central and local governments for a viable development of fish-paste processing business companies in Busan.

• 마이크로전자및패키징학회지
• /
• 제15권1호
• /
• pp.27-31
• /
• 2008

전자 부품의 소형화 요구에 따라서 기존 기판의 상부에 실장 되는 저항 소자를 감소하기 위한 방안으로 후막 저항 페이스트를 인쇄하여 저항체를 형성 한 후에 내장하는 수동소자 내장기술이 활발히 연구되고 있다. 본 연구에서는 카본 블랙과 에폭시 수지를 혼합하여 $0.35{\sim}4k{\Omega}/sq$으로 넓은 저항 범위를 가지는 저온 열경화형 후막 저항 페이스트를 제작하였으며, Ni-Cr alloy와 $SiO_2$ 분말을 첨가하여 온도에 따른 저항 변화인 TCR(Temperature Coefficient Resistivity) 값을 $100ppm/^{\circ}C$으로 개선하였다. 최종적으로 제작된 저항 페이스트를 이용하여 내장 저항 기판을 제작하였으며 온도에 변화에 따른 안정적인 저항 특성과 신뢰성을 확보 할 수 있었다.

• 한국식품영양학회지
• /
• 제21권3호
• /
• pp.288-292
• /
• 2008

To save cost and time in Kimchi manufacture, the use of raw red-pepper paste and device-mashed vice materials, in place of dried red-pepper powder, was examined. Two kinds of Kimchi were prepared: One with dried red pepper powder and device-not mashed vice materials and the other with raw red pepper paste and device-mashed vice materials. Then pH, total acidity, total viable cell counts, total lactic acid bacteria and sensory characteristics were evaluated. Comparisons of the two Kimchis, indicated that changes in pH, total acidity, the total number of viable cells and total lactic acid bacteria were similar between the two groups. The acceptability score of the Kimchi made using the raw red pepper paste and device-mashed vice materials was slightly lower than that of Kimchi made using the dried red-pepper powder. This color was indistinctly changed since the vice materials were mashed and mixed. In conclusion, the results indicate that when manufacturing Kimchi using device-mashed vice materials, Kimchi of better quality can be made by adding dried red-pepper powder.

• 한국응용과학기술학회지
• /
• 제33권3호
• /
• pp.568-574
• /
• 2016

In this study, the mixing method of positive paste and mixing temperature to improve the capacity of the lead-acid batteries has been investigated. The results show that the initial current capacity of lead acid battery depend on the mixing temperature and mixing method of positive paste. In the results of the capacity cycle repetition tests for estimating the life cycle, the 3BS showed the PCL. but the fine 4BS represented certain improved cycles compared to that of the coarse 4BS. It was considered that the fine 4BS showed higher bond strength between active materials than the coarse 4BS and represented large contact areas and that lead to prevent possible sulfation due to the suppression of insulating layers.

• 한국건축시공학회:학술대회논문집
• /
• 한국건축시공학회 2019년도 춘계 학술논문 발표대회
• /
• pp.112-113
• /
• 2019

Recently, supplementary cementitious materials such as blast-furnace slag, fly ash and silica fume have been widely used as substitutes for cementitious materials. In this study, the deformation behavior of compressive loading of C₃S paste with 50% fly ash was analyzed by X-ray scattering data and pair distribution function analysis. The obtained results were compared with 131-day-old pure C₃S paste. The Ca(OH)₂ of the C₃S-FA paste showed almost complete elastic behavior, consistent with the deformation behavior of the r-range of 20 to 40, and the C-S-H phase contributed to the range of PDF r-range of less than 20. In addition, C-S-H of C₃S-FA showed greater deformation resistance than C₃S paste.

• 한국콘크리트학회:학술대회논문집
• /
• 한국콘크리트학회 1991년도 가을 학술발표회 논문집
• /
• pp.11-14
• /
• 1991

Apparent diffusion coefficients of Cl-ions through hardened cement paste(HCP), which were partly substituted blending materials, were determined. Also, pore solution was extracted from HCP which were immersed in NaCl solution, and Cl- concentration of the solution were analyzed. Partly substitution of pozzolanic materials considerably reduced the diffusion rate for Cl-ions and Cl- concentration of pore solution. Binding capacity of Cl- is related to the content of Al2O3 and pozzolanic reactivity.

• 한국건축시공학회지
• /
• 제17권2호
• /
• pp.183-189
• /
• 2017

플라이애시는 시멘트 계열 재료의 혼화재료로서 널리 사용되고 있는 재료이다. 다만, 플라이애시는 화력발전소의 석탄재를 포집하여 정제과정을 거친 재료로서 정제과정의 에너지 소모 및 유통과정에서의 품질 확보가 중요하다. 이에 본 연구에서는 플라이애시 생산과정 중 발생하는 세 가지 종류의 다른 품질의 석탄재를 대상으로 각각의 입자조건과 시멘트 페이스트 상태에서 레올로지 거동을 평가하였다. 실험결과 리젝트 애시는 작은 석탄재 입자가 응집되어 굳어진 다공질의 큰 입자로 구성되어 있었고, 그러한 이유로 시멘트 페이스트에 포함될 경우 공기량이 높게 측정되는 경향이 나타났다. 유동성 측면에서는 석탄재가 치환되는 경우 유동성이 증진되는 양상을 보였으며 특히 점도 측면에서는 입자조건에 따라 점도를 조정할 수도 있었다.