• 공업화학
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• 제20권6호
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• pp.692-695
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• 2009

바닥의 전기난방 장치로 사용할 수 있는 오믹 줄 방전 현상을 이용하는 면상발열체 전극기술을 개발하였다. Super pure black의 탄소재료와 polyvinylidene fluoride의 고분자 재료를 이용하여 제조한 복합 전극 합제를 PET에 박막 도포하여 전극을 제조하였다. 전극에 대한 조성 첨가제로서 multi-walled carbon nanotube와 연옥 분말을 사용하였다. 개발한 면상발열체 전극의 비저항과 전극의 접착강도 및 전극의 강도에 대하여 연구하였다. 연옥 분말의 첨가는 비저항과 강도에 미치는 영향이 적었으며, carbon nanotube의 첨가는 전극의 비전도도와 경도를 향상하였다. 다양한 조성의 오믹 줄 방전 전극의 특성을 연구하였다.

• 한국축산식품학회지
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• 제44권2호
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• pp.483-497
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• 2024

This study investigated the effects of ultra-ground seaweed powders (USP) on the physicochemical properties (proximate composition, mineral contents, pH, color, shear force, sensory evaluation, electronic nose, and electronic tongue) of restructured black goat jerky. Restructured black goat jerky was prepared using three different treatments, i.e., 3% (w/w) each of ultra-ground sea tangle (ST; Undaria pinnatifida), sea mustard (SM; Saccharina japonica), and sea string (SS; Gracilaria verrucosa) powders. Moisture and ash contents were significantly higher in the USP-treated group than in the control (p<0.05). Potassium, calcium, and zinc contents were significantly higher in the SM than in the other USP-treated groups (p<0.05). In contrast, pH values were significantly higher in the ST and SM than in the control and SS (p<0.05). CIE L^*, CIE a^*, CIE b^*, and shear force were significantly lower in the USP-treated groups than in the control (p<0.05). Sensory evaluation revealed no significant difference in taste, texture, seaweed-like odor, and goaty flavor (p<0.05). Principal component analysis (PCA) and peak graph analysis of the electronic nose showed that the SS differed the most from the control compared with the other USP-treated groups, owing to the seaweed odor of ultra-ground SS powder. The PCA and ranking analysis of the electronic tongue showed that the umami taste of the SM was higher than that of the control and other USP-treated groups. Therefore, the potassium, calcium, zinc contents, and umami taste of reconstituted black goat jerky were significantly higher in the SM than in the control and other USP-treated groups.

• 한국식생활문화학회지
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• 제38권5호
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• pp.356-364
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• 2023

This study compared the physicochemical properties of soybean curd residue and black soybean curd residue produced by hot air-drying and freeze-drying. Regardless of drying method, the crude protein, crude ash, crude fiber contents, pH, L, a, b color values and water soluble index were higher in soybean curd residue, whereas total polyphenol contents and antioxidant activity were higher in black soybean curd residue. Significant differences in water absorption index, oil absorption capacity and emulsion activity were observed between soybean curd residue and black soybean curd residue in freeze-drying. On the other hand, the emulsion stability was not significant difference in both hot-air drying and freeze-drying. The crude protein and crude fiber contents of soybean curd residue were not significant difference between hot-air drying and freeze-drying. Freeze-drying resulted in higher crude ash contents, pH, water absorption index, water soluble index, oil absorption capacity, emulsion activity and emulsion stability than hot-air drying. Hot-air drying have caused significantly higher water contents, water activity, total polyphenol contents and antioxidant activity in soybean curd residue than freeze-drying. In conclusion, soybean type and drying methods affect the physicochemical and quality characteristics of soybean curd residue, which could be important factors in the manufacture of processed foods.

• 화약ㆍ발파
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• 제27권1호
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• pp.53-61
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• 2009

대한민국의 화약생산 기원은 고려시대에 중국으로부터 흑색화약이 처음으로 전수되었으며, 1890년 경남마산에서 흑색화약이 채광발파에 처음 사용되었고, 최근에는 지하철굴착 도로굴착 건물폭파해체 등 거의 대부분의 건설시장에 에멀젼폭약을 사용하는 진동제어발파공법 기술이 자리를 잡게 되었다. 2006년 12월에는 세계에서 처음으로 진동제어발파공법을 위주로 한 발파설계 시공지침을 국가와 전문학회의 주도로 완성하였다.

• 한국분말재료학회지
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• 제16권5호
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• pp.310-315
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• 2009

Ultra-fine TiC/Co composite powder was synthesized by the carbothermal reduction process without wet chemical processing. The starting powder was prepared by milling of titanium dioxide and cobalt oxalate powders followed by subsequent calcination to have a target composition of TiC-15 wt.%Co. The prepared oxide powder was mixed again with carbon black, and this mixture was then heat-treated under flowing argon atmosphere. The changes in the phase, mass and particle size of the mixture during heat treatment were investigated using XRD, TG-DTA and SEM. The synthesized oxide powder after heat treatment at 700$^{\circ}C$ has a mixed phase of TiO$_2$ and CoTiO$_3$ phases. This composite oxide powder was carbothermally reduced to TiC/Co composite powder by the solid carbon. The synthesized TiC/Co composite powder at 1300$^{\circ}C$ for 9 hours has particle size of under about 0.4 $\mu$m.

• 한국건축시공학회:학술대회논문집
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• 한국건축시공학회 2018년도 춘계 학술논문 발표대회
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• pp.212-213
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• 2018

The cementitious composites have been developed to satisfy various demands of the construction market. The conductive concrete, which is a carbon-based cementitious composite, was used for the deicing or the detecting the internal crack. The cement-based battery is a technology that applies the basic concept of the alkaline battery to these conductive concretes. The cementitious composites could have a function as batteries, through a mixing of anode and cathode, which were consist of the zinc and manganese dioxide powder. The carbon-based materials, which have a significant effect on electrical properties, could be considered as the main variable in cement-based batteries. Therefore, in this study, the effects of carbon-based materials were investigated. Two types of materials, including the Carbon black and Multi-walled carbon nanotube(MWCNT), were considered as the main variables. From the experiment results, the electrical characteristics such as resistance, voltage, and current were compared according to the age.

• 한국분말재료학회지
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• 제12권2호
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• pp.112-116
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• 2005

In the present study, the focus is on the analysis of carbothermal reduction of oxide powder prepared from waste WC/Co hardmetal by solid carbon under a stream of argon for the recycling of the WC/Co hard-metal. The oxide powder was prepared by the combination of the oxidation and crushing processes using the waste $WC-8 wt.\%Co$ hardmetal as the raw material. This oxide powder was mixed with carbon black, and then this mixture was carbothermally reduced under a flowing argon atmosphere. The changes in the phase structure and gases discharge of the mixture during carbothermal reduction was analysed using XRD and gas analyzer. The oxide powder prepared from waste $WC-8wt.\%Co$ hardmetal has a mixture of $WO_{3} and CoWO_{4}$. This oxide powder reduced at about $850^{\circ}C$, formed tungsten carbides at about $950^{\circ}C$, and then fully transformed to a mixed state of tungsten carbide (WC) and cobalt at about $1100^{\circ}C$ by solid carbon under a stream of argon. The WC/Co composite powder synthesized at $1000^{\circ}C$ for 6 hours from oxide powder of waste $WC-8wt.\%Co$ hardmetal has an average particle size of $0.3 {\mu}m$.

• 한국세라믹학회지
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• 제33권5호
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• pp.479-484
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• 1996

The tribological properties of ceramics are very important in the application to engineering ceramic parts such as mechanical seal slurry valve disc and so on. In this study the effect of graphite addition on the mechanical and tribological properties of RBSC/graphite composites were investigated. The composites were prepared by adding graphite powder to the mixture of SiC powder metallic siliconcarbon black and alumina. Bending strength water absorption friction coefficient the amount of worn out material at a certain time and maximum surface roughness(Rmax) of the prepared composites were measured and crystalline phases were examined with XRD. The composite containing 5 vol% graphite powder showed improved bending strength due to high green density and decreased friction coefficient and wear resistance. The friction coefficient and the wear resistance of the composite were increased by adding graphite powder up to 10 vol% They decreased however as increasing the amount of graphite powder more that 10vol% There was no linear relationship between the tribological properties and bending strength of the composites.

• 동아시아식생활학회지
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• 제22권1호
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• pp.52-61
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• 2012

This study sought to develop a healthier type of jeungpyeon, or Korean rice cake, by adding Korean black raspberry powder (Rubus coreanus). The moisture content, color, volume, symmetry, uniformity, texture, and sensory quality characteristics were evaluated in order to determine the optimal amount of raspberry powder to add to rice flour in order to get the best-tasting, healthiest food. We substituted 0.5%, 1.0%, 1.5% and 2.0% of rice flour with Rubus coreanus powder and mixed 3%, 6%, 9% and 12% Rubus coreanus concentrate with water to make dough. The result was stored for up to 48 hours at $20^{\circ}C$, and then evaluated. Jeungpyun with Rubus coreanus powder and Rubus coreanus concentrate had the right flavor, color, fermentation, and taste, compared to the other groups. Consequently, in overall acceptability, the highly rated Rubus coreanus powder-PW(1.5%) and Rubus coreanus concentrate - BA (6%) will be the most desirable.

• 한국식품영양과학회지
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• 제42권1호
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• pp.143-147
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• 2013

흑임자 분말 첨가량을 0~12%로 달리하여 양갱을 제조하고 이화학적 품질, 항산화특성 및 소비자 기호도를 조사하였다. pH는 흑임자 분말 첨가량이 증가할수록 유의적으로 증가하였다(p<0.05). $L^*$값과 $b^*$값은 유의적으로 감소하였고, $a^*$값은 증가하였다(p<0.05). 한편 흑임자 분말 첨가량이 증가함에 따라 양갱의 경도는 유의적으로 증가하였다(p<0.05). 항산화활성을 나타내는 총 폴리페놀 함량과 전자 공여능은 흑임자 분말 첨가량이 증가함에 따라 유의적으로 증가하는 경향을 나타내었고(p<0.05), 전자 공여능에서 보다 현저한 증가를 보였다. 소비자 기호도검사 결과 6% 첨가군이 모든 평가항목에서 유의적으로 높은 평가를 받아 양갱의 관능적 품질을 최대한 유지하면서 흑임자 분말의 기능적 이점을 최대한 활용하기 위한 최적 첨가 농도는 6%가 가장 적합한 것으로 판단된다.