• Advanced Composite Materials
• /
• 제18권4호
• /
• pp.315-326
• /
• 2009

PCC (precipitated calcium carbonate) and ground calcium carbonate have been widely used in alkaline papermaking. Unfortunately, although increasing filler level in papers can improve the paper properties such as brightness, opacity, stiffness gloss, smoothness, porosity, and printability, as well as decrease cost, some strength of the paper is negatively affected. In this research, needle-like aragonite was synthesized using $Ca(OH)_2$ and $CO_2$ as reactants in the presence of $MgCl_2$ and characterized with scanning electronic microscopy (SEM) and X-ray diffraction (XRD). The physical and optical properties of the paper handsheets containing these needle-like aragonite fillers were evaluated. Results indicated that tensile strength, Z-direction tensile strength and folding endurance of the paper were improved by the needle-like aragonite crystals compared to the paper using commercial PCC (precipitated calcium carbonate) as filler. The stiffness of the paper handsheet on the machine direction was increased, but no evident difference in the cross direction was found. The improvement of paper strength mainly resulted from the twining effect between the aragonite whiskers and paper fibers. The optical properties of the paper were slightly decreased with the use of the needle-like aragonites compared to commercial PCC. These results suggest that paper cost can be decreased by increasing the content of needle-like aragonite filler while paper strength will not be decreased compared to PCC filler.

• 한국수산과학회지
• /
• 제55권5호
• /
• pp.533-540
• /
• 2022

We evaluated a worm-based extruded pellet diet with black soldier fly Hermetia illucens larvae (BSF) meal and BSF oil for olive flounder Paralichthys olivaceus through field feeding experiments at a commercial aquafarm. We prepared two experimental diets by replacing fish meal and fish oil with BSF meal and BSF oil (BEP-1, BSF meal 7%, BSF oil 1%) and (BEP-2, BSF oil 2%), respectively. We prepared raw-fish based moist pellets (MP) for comparison between the two experimental diets. We distributed the olive flounder (220±6.29 g) in square (10 m×10 m×1 m) concrete, 100 ton tanks at a density of 1,600 fish per tank (n=3) in triplicate for each dietary treatment. We fed the diets to the fish to apparent satiation for 7 months. At the end of the feeding trial, we found no substantial differences between the groups in terms of growth performance, survival, or feed utilization. None of the diet groups showed any changes in either hematological or non-specific immune responses. The histological observation of the intestine showed that the goblet cell number and cholecystokinin-producing cell activity increased in the fish fed the BEP diet compared with the those of the fish fed the MP diet. These results indicated that dietary BSF meal and oil can be used for olive flounder without compromising growth or, hematological and histological parameters.

• 한국식품조리과학회지
• /
• 제18권3호
• /
• pp.275-279
• /
• 2002

동부 묵가루 제조 방법과 대두유 첨가량과 소금의 첨가 유무를 달리한 묵을 제조하여 기계적인 texture특성을 측정하고, 관능검사를 실시하여 대두유와 소금의 첨가가 묵의 품질특성에 미치는 영향을 검토한 결과를 요약하면 다음과 같다. 1. 소금의 첨가유무에 관계없이 대두유의 첨가량이 많을수록 hardness, chewiness는 전반적으로 감소하는 경향이었으나, cohesiveness, springiness는 대두유 첨가량에 따라 큰 차이가 없었다. 시판 묵가루를 이용하여 만든 묵이 실험실 제조 묵가루를 이용한 묵보다 hardness는 높았고, cohesiveness는 낮았으며, springiness, chewiness는 큰 차이를 나타내지 않았다. 2. 관능검사 결과 대두유를 첨가할수록 노르스름하고, 불투명하며, 느끼하고, 부드럽게 평가되었으나, 전반적인 바람직성에서는 바람직하지 않은것으로 평가되었다. 그러나 소금을 첨가하였을 경우 소금을 첨가하지 않은 시료보다 대두유 첨가량에 따른 차이가 적었으므로 묵 제조 시 대두유와 소금을 첨가하여 부드러우며, 기본적인 간을 나타내는 묵을 만들 수 있을 것으로 생각된다.

• 한국식품위생안전성학회지
• /
• 제8권3호
• /
• pp.151-155
• /
• 1993

참기름에 이종의 식용유를 혼합하였을 때 이를 판별할 수 있는 방법을 연구하기 위하여, 순수한 참기름을 비롯한 일반적인 식용유 5종의 UV흡수양상을 조사하여 각 식용유의 UV흡수특성을 이용하여 순수한 참기름과 혼합 기름을 구별할 수 있는 근거를 마련하였다. 순수한 참기름의 spectrum은 215, 230 및 290 nm에서 흡수피크를 형성한 반면, 옥수수유, 들기름 및 대두유는 모두 215, 230 및 280 nm에서, 그리고 미강유는 215, 290 및 320 nm에서 흡수피크를 형성하였다. 참기름의 290 nm에서의 흡수피크는 참기름 제조과정인 참깨의 볶는 온도와 시간이 증가할수록 그 흡광도가 증가하는 경향이 있었으며, 일반적인 조건으로 추정되는 $200^{\circ}C$, 60분간 볶은 후 제조한 참기름은 대략 0.7 정도의 흡광도를 나타내었다. 참기름에 미강유를 혼합한 기름에서는 320 nm에서 미강유의 존재를 확인할 수 있는 흡수피크가 나타나고, 참기름에 옥수수유, 들기름 또는 대두유를 각각 혼합한 기름들은 290 nm에서의 흡광도가 순수한 참기름의 흡광도에 비하여 적었으며, 이종기름의 혼합율이 높을수록 비례적인 감소를 나타내었다.

• 한국축산식품학회지
• /
• 제26권3호
• /
• pp.276-283
• /
• 2006

쑥 분말 3 %, 정어리유 4 %, 쑥 분말 3 %와 정어리유 4 %를 처리구에 따라 5주간 급여한 후 도계하여, 가슴살과 다리살을 냉장온도($4{\pm}1^{\circ}C$)에서 15일간 저장하면서 지방산 조성, TBARS가, 보수성, 육즙 손실의 변화를 조사하였다. 지방산은 근육의 부위 및 쑥과 어유의 급여 수준에 관계없이 oleic acid, palmitic acid, linoleic acid, stearic acid의 순으로 함량이 높았으나, 유의성은 없었다(p<0.05). 또한 T3 처리구에서는 palmitoleic acid와 EPA, DHA의 함량이 대조구보다 많았다. TBARS가는 저장기간이 경과함에 따라 전처리구에서 증가하였고(p<0.05), 전반적으로 다리살 부위가 가슴살부위의 TBARS가 보다 높은 경향이었다. 보수력은 저장기간이 경과함에 따라 가슴살과 다리살의 보수력은 증가하는 경향이었고(p<0.05), 처리구간에서는 서로 비슷하였으며, 전반적으로 가슴살이 다리살 부위보다 보수력이 높았다. 육즙 손실은 저장기간이 경과함에 따라 전처리구에서 점차 증가하였고(p<0.05), 처리구간에서는 T1구와 T3구가 상대적으로 육즙 손실이 적었다.

• Journal of Microbiology and Biotechnology
• /
• 제15권6호
• /
• pp.1183-1188
• /
• 2005

Several lipases of commercial grade were screened to catalyze the methanolysis of castor oil, and an immobilized Candida antarctica (Novozym 435) had the highest activity among the lipases tested. To enhance the yield of methyl ricinoleate, several reaction parameters were optimized. The optimum temperature was $50^{\circ}C$, and the original water content of lipase was sufficient to maintain the activity of lipase, and additional water supplied inhibited the methanolysis of castor oil. Because the lipase was deactivated by methanol, the reaction was tested by three-step addition of 1 molar equivalent of methanol to the oil. However, the oil was not completely converted to its methyl esters. The final reaction mixture using 3 molar equivalents of methanol to the oil consisted of $70\%$ methyl ricinoleate, $18\%$ monoricinoleate, $11\%$ diricinoleate, and trace triricinoleate at the equilibrium state. The yield of methyl ricinoleate was $97\%$ at 6 molar ratio of methanol to the oil with 300g of castor oil and 6g of immobilized Candida antarctica at $50^{\circ}C$ within 24 h.

• 한국마린엔지니어링학회:학술대회논문집
• /
• 한국마린엔지니어링학회 2005년도 전기학술대회논문집
• /
• pp.205-209
• /
• 2005

Now a days Automobiles are becoming more important in our life, the study on piston of engine is needed because, piston's cooling and lubrication of piston have an effect on the life and efficiency of engine directly. So, this study is about nozzle part of oil jet for cooling piston in the automotive engine. Piston exposes combustion gas of over $2000^{\circ}C$ and is shocked high pressure at the time of explosion shortly. Furthermore strong friction occurs by high speed rotation. The cooling system is considered from oil jet to piston. The previous system cooled the lower part of piston only. So, efficiency was low. To improve this system, make the oil gallery in the piston, and oil flows into the gallery. The value of oil flow rate into the gallery is important. Consequently, the point of this study is the research of investigation of flow characteristics for variable Re number. This study has been modelled by a commercial CFD code FLUENT, allowing to assess its validity

• 한국정밀공학회지
• /
• 제29권7호
• /
• pp.793-798
• /
• 2012

Oil gear pump is used for the cooling pump system of commercial vehicle. The hydraulic pulsation pressure of oil gear pump is one of the most important reasons for the vibration and noise of the pump. In this study, the several hydraulic factors acting on oil gear motor are analyzed by CFD in operation of cooling system. Forced vibration analysis due to hydraulic pulsation pressure is analyzed by FEA for predicting deformation and equivalent stress.

• 신재생에너지
• /
• 제5권4호
• /
• pp.52-58
• /
• 2009

Upgrading of pyrolysis wax oil using HZSM-5 catalyst has been conducted in a continuous fixed bed reactor at $450^{\circ}C$, 1hour, LHSV 3.5/h. The catalytic degradation was studied with a function of catalyst amount and reaction temperature. The raw pyrolysis wax oil shows relatively high boiling point distribution ranging from around $300^{\circ}C$ to $550^{\circ}C$, which has considerably higher boiling point distribution than that of commercial diesel. The catalytic degradation using HZSM-5 catalyst shows the high conversion of pyrolysis wax oil to light hydrocarbons. The liquid product obtained shows high gasoline range fraction as around 90% fraction and considerably high aromatic fraction in liquid product. Here, the experimental variable such as catalyst amount and reaction temperature was influenced on the product distribution.

• 한국식품영양과학회지
• /
• 제31권1호
• /
• pp.17-20
• /
• 2002

경남 도내에서 유통 중인 국내산 참기름과 중국산 참기름 각각 30건과 콩기름 및 옥수수기름 등의 식용유지를 첨가하여 변조한 참기를 12건에 대한 지방산 함량을 GC에 의한 정량법으로 분석하여 다음과 같은 결과를 얻었다. 국내산 참기름의 주요 지방산 평균 함량은 palmitic acid 8.26$\pm$0.04%, stearic acid 4.57$\pm$0.05%, oleic acid 39.25$\pm$0.05%, linoleic acid 46.82$\pm$0.07, linolenic acid 0.52$\pm$0.02%, arachidic acid 0.58$\pm$0.03% 등으로 나타났으며, 중국산 참기름은 palmitic acid 9.24$\pm$0.03%, stearic acid 5.11$\pm$0.04%, oleic acid 38.65$\pm$0.04%, linoleic acid 46.02$\pm$0.06%, linolenic acid 0.42$\pm$0.04%, arachidic acid 0.56%$\pm$0.04% 등으로 각각 나타났다. 국내산 참기름은 포화 지방산인 palmitic acid와 stearic acid가 중국산 참기름보다 적게 함유되어 있었고 불포화 지방산인 linolenic acid는 반대로 많이 함유되어 있었다. 국내산 참기름에 콩기름을 0%, 3%, 9%씩 첨가했을 때 불포화지방산인 linolenic acid가 각각 0.52$\pm$0.02%, 0.73$\pm$0.05%, 1.25$\pm$0.04%로 현저히 증가되었으며, 옥수수기름을 0%, 5%, 9%씩 첨가했을 때는 불포화지방산인 linoleic acid의 함량이 각각 46.82$\pm$0.07%, 50.22$\pm$0.06%, 51.14$\pm$0.05%로 증가됨이 확인되었다. 참기름의 산지별 확인과 식용유지를 첨가한 변조참기름에 대해서는 각각의 지방산 함량에서 특이성을 보이고 있으나 일부지역에서 구입한 국내산과 중국산 참기름에서 유사한 결과치를 보여 앞으로 국내에서 유통되는 참깨나 참기름에 대하여 더 많은 연구가 필요할 것으로 사료된다.