• Applied Chemistry for Engineering
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• v.29 no.1
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• pp.1-9
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• 2018

Microalgae is considered as one of environmentally sustainable and potential feedstocks to produce biodiesels. However, recent studies on life cycle assessments (LCA) of microalgal buidiesels have shown that energy requirement is not small to produce biodiesel from microalgae, especially during cultivation stage. The costs for carbon sources, nutrients like nitrogen or phosphorous, and water for cultivation can contribute up to 80% of the total medium costs. In the present article, recent trends on the utilization of several promising nutrient sources such as municipal wastewaters, organic fertilizers, combustion exhaust emissions and organic solid wastes were reviewed, and the potential strategies to be used as substitutes of artificial culture media, especially for the biodiesel production, were discussed.

• Journal of the Korean Crystal Growth and Crystal Technology
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• v.21 no.2
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• pp.87-91
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• 2011

The purpose of this study is to develop ceramic glazes for the pottery production by utilizing wasted white porcelain, celadon porcelain and bone china thrown away from the areas of Icheon and Yeoju. Most of Korean pottery manufacturers are located in the both areas. According to the XRF analysis, the wasted white porcelain contains over 67 % of silica. It is enough to make a transparent glaze without adding silica. The wasted celadon porcelain contains much $Fe_2O_3$, which is suitable for producing a celadon glaze. The wasted bone china contains 22 % of $P_2O_5$, which is suitable for making a milky white bone china glaze. As a result, it is expected that production of pottery glaze using the wasted porcelains will reduce pollution problems comes from the landfill, and obtain economic effects in terms of resources recycling. It is also expected to be utilized as alternative materials of imported ones.

• Applied Biological Chemistry
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• v.37 no.4
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• pp.266-271
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• 1994

In order to investigate the effects of the mixing ratio of rice on Doenjang, Meju Doenjang and Koji Doenjang were prepared respectively with oaring mix ratio of raw materials. The following results were obtained, after fermentation of up to 3 months. Significant differences between the kinds of Doenjang were not found in moisture and salt contents. Protein solubility $(water\;soluble\;nitrogen/total\;nitrogen{\times}100)$ was $32{\sim}50%$ and $14{\sim}24%$ in Koji Doenjang and Meju Doenjang, respectively. Protein digestibility $(formol\;nitrogen/total\;nitrogen{\times}100)$ was similar to the tendency of protein solubility. Reducing sugar content was $5{\sim}6%$ in Meju Doenjang, while $19{\sim}21%$ in Koji Doenjang. As the mixing ratio of rice increased, reducing sugar content also increased. Sensory evaluation showed that Koji Doenjang was desirable than Meju Doenjang and the mixing ratio of 20% rice was recommened for Koji Doenjang.

• 한국신재생에너지학회:학술대회논문집
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• 2007.11a
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• pp.301-304
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• 2007

다결정 태양전지의 원료인 폴리실리콘을 생산하는 방법 중 하나인 지멘스 방법에서 사용되는 실리콘 코어로드를 금속 계열의 코어로드로 대체하기 위한 연구를 진행하였다. 본 연구에서는 실리콘 코어로드의 대체물질 후보로서 고융점 금속인 텅스텐, 탄탈륨, 몰리브덴을 선택하였고, co-sputtering system을 이용하여 다성분계의 박막을 실리콘 기판에 증착시켜 $800^{cdot}C$에서 $1000^{cdot}C$의 고온에서 열처리 후 박막의 형상변화 및 확산정도를 관찰하였다. 열처리 온도에 따른 박막의 형상 및 확산 정도를 관찰하기 위하여 Scanning electron microscopy (SEM), X-ray diffractometer(XRD), transmission electron microscopy(TEM), auger electron spectroscopy(AES)가 사용되었다.

• Journal of Biosystems Engineering
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• v.9 no.2
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• pp.58-64
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• 1984

디이젤엔진의 대체연료(代替燃料)로서 대두유(大豆油)는 대두유(大豆油)의 높은 점성(粘性)에 기인(起因)하는 문제점이 지적되고 있다. 이외 해결방법으로 대두유(大豆油)와 디이젤유(油)의 혼합(混合), 대두유(大豆油)의 에스테르화(化) 그리고 디이젤유(油) 첨가제(添加劑)의 첨가(添加) 등이 제시되고 있다. 본(本) 연구(硏究)는, 대두유(大豆油), 그의 에틸 에스테르 그리고 이러한 대체연료(代替燃料)의 디이젤유(油)와 혼합물(混合物) 또는 그 혼합물(混合物)의 첨가제(添加劑)와의 혼합물(混合物)의 점성학적 성질(性質)과 그 크기를 실험적 방법(方法)으로 구하였다. 그 결과 상기의 액체는 모두 뉴톤니안 액체이고, 첨가제(添加劑)는 상기 혼합물(混合物)의 점성(粘性)을 낮추는데 별로 효과가 없는 것으로 판단되었다.

• Korean Journal of Food Science and Technology
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• v.41 no.2
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• pp.173-178
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• 2009

Epidemiological studies showed that high trans-fat consumption is closely associated with getting the risks of cardiovascular disease. The objective of this study was to produce trans-free fat through lipase-catalyzed interesterification, as a substitute for the cream margarine commonly used in industry. Optimum conditions for interesterification in a packed bed enzyme bioreactor (PBEB) were determined using response surface methodology (RSM) based on central composite design. Three kinds of reaction variables were chosen, such as substrate flow rate (0.4-1.2 mL/min), reaction temperature (60-70$^{\circ}C$), and ratio of fully hydrogenated canola oil (FHCO, 35-45%) to evaluate their effects on the degree of interesterification. Optimum conditions from the standpoint of solid fat content (SFC) were found to be as follows: 0.4 mL/min flow rate, 64.7$^{\circ}C$ reaction temperate, and 42.8% (w/w) ratio of FHCO, respectively. The half-life of immobilized lipase in PBEB with two stages at 60$^{\circ}C$ ($1^{st}$ stage) and 55$^{\circ}C$ ($2^{nd}$ stage) was about more than 30 days as estimated by extrapolating the incubation time course of tristearoyl glycerol (TS) conversion, whereas the half-life of the enzyme in PBEB with single stage at 65$^{\circ}C$ was only about 15 days. Finally, the results from SFC analysis suggest that trans-free fat produced in this study seems to be a suitable substitute for the cream margarine commonly used in industry.

• Korean Journal of Food Science and Technology
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• v.6 no.2
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• pp.65-69
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• 1974

Noodles were made from composite flours based on barley or sweet potato/wheat flour and their quality was assessed to obtain the following results. 1) In noodle sheet and dried noodle formation, barley flour could substitute 100% and sweet potato flour, 70% of wheat flour and their textural characteristics were improved by addition of glyceryl monostearate and sodium polycrylate. 2) Textural parameters such as hardness, cohesiveness and gumminess of noodle sheet and dried noodle were decreased by admixture of barley of sweet potato flour whereas they were increased by use of the additives. Noodle sheet required hardness over 6.2 and gumminess over 430 while dried noodle needed hardness over 6.8. 3) In cooked noodle, replacement of wheat flour and use of additives tended to lower the textural parameters. With respect to the cooking quality, barley flour could substitute 60% and sweet potato flour, 40% of wheat flour. 4) In organoleptic evaluation of cooked noodle with respect to its color, taste and texture, 20% replaced composite flour was not different significantly at 5% level from wheat flour and the quality defect was mainly due to discoloration of the product.

• Food Science of Animal Resources
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• v.28 no.4
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• pp.395-400
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• 2008

This study was carried out to compare the textural properties of crab-flavored sausage manufactured with six different formulations. We prepared crab-flavored sausage from Alaska pollack surimi as a control by the washing method, and various mixtures of surimi and chicken breast meat were manufactured (pH 11.0) with 33.33% chicken breast meat (CBM) (T1), 50% CBM (T2), 66.66% CBM (T3), 100% CBM (T4) and 20% commercial mechanically deboned chicken meat (MDCM) (T5). Brittleness, gumminess, chewiness, breaking force, gel strength, jelly strength, sensory flavor. texture, and overall acceptability were significantly lower in the formulations containing chicken meat in proportion to the % CBM (p<0.05). However, cohesiveness and springiness were significantly higher in the formulations containing chicken meat in proportion to the amount of CBM (p<0.05). Folding test and deformation values were significantly lower in the surimi manufactured with CBM at pH 11.0. although T5 showed no significant differences relative to the control. Overall, these results indicate that similar textural properties in the crab-flavored sausage were attained when surimi was prepared with 20% CBM and MDCM.

• Journal of the Korean Recycled Construction Resources Institute
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• v.7 no.2
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• pp.166-173
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• 2019

In this paper, the reaction properties of silica source in the accelerated curing conditions using autoclave and the fundamental properties of inorganic Micro Defect Free(MiDF) concrete using silica source are studied. Studies show that Si ions elution rate from silica source in autoclave curing is higher in amorphous source. In tap water conditions, solids which is source after autoclaved curing show a higher mass reduction in amorphous materials, which is attributed to the higher elution rate of ion. In $Ca(OH)_2$ solution conditions, amorphous materials show higher mass increase, due to increase in C-S-H minerals. From experiment for influence on the properties of MiDF concrete by using nano silica materials, the specimen with silica fume shows an increase in compressive strength and a decrease in absorption depending on replacement rate up to 5.5%, while nano silica with amorphous phase and high-fineness shows a decrease in compressive strength and decrease in the water absorption. The specimen with nano silica increases the pore below 10,000nm, but reduces pore between 10,000 and 100,000nm. The above results show that the porosity and absorption rate of MiDF concrete can be reduced by using amorphous nano-size silica. However, to reduce the pore of 50 to 10,000nm, better dispersion of nano material in the cement matrix will be necessary. We will focus on the this item in the next research.

• Journal of Animal Science and Technology
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• v.48 no.5
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• pp.739-746
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• 2006

The objective of this study was to evaluate the quality of emulsion-type sausage where part of the pork was substituted with horse meat during manufacturing. Three treatments of sausages were manufactured by replacing pork with 0, 50 and 100% horse meat. After manufacturing, sausages were vacuum-packaged and stored 4℃ for 1 day. An increase in horse meat resulted in higher moisture, protein content, and pH values, and lower fat content of sausage(P<0.05). However, no significant effects were observed on texture characteristics and sensory attributes of sausage. The horse meat sausage had higher K, Fe, Zn, Cu, saturated fatty acid contents than 0% horse meat level. Based on the results, it can be concluded that horse meat can be used as a meat replacer in the manufacture of emulsion-type sausages up to a level of 100%.