• 해양환경안전학회지
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• 제26권7호
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• pp.858-863
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• 2020

본 연구에서는 활성탄소를 이용하여 해양환경으로 유출된 침강 HNS를 현장에서 대응하기 위한 기술 개발을 목적으로, 활용 가능한 활성탄소의 조건을 검토하고 예상 소요량을 산출하였다. 입자 크기별 7종의 활성탄소들을 대상으로 침강 속도를 측정하였고, 침강 HNS로 분류된 클로로포름(CHCl3)에 대한 흡착용량을 실험실 규모 실험(lab-scale test)으로 측정하였다. 또한 7종 활성탄소들에 대하여 유해물질함량과 용출 실험을 실시하여 용출된 유해물질 함량을 정량 분석하였다. 평균 침강속도(Mean particle-settling velocity)는 0.5~8 cm/sec의 범위로 8-20 mesh 경우를 제외하고 입자의 크기가 클수록 침강속도가 빨랐으며, 클로로포름에 대한 흡착효율은 대체로 입자가 작을수록 표면적이 넓어져 증가되었다. 또한 현장 투입 후 2차 오염가능성 확인을 위한 유해물질함량과 용출 실험 실험에서 >100 mesh의 활성탄소는 전함량분석결과가 아연(Zn)과 비소(As)가 수처리제기준보다 높고, 용출실험결과에서도 크롬(Cr), 아연(Zn), 비소(As)가 다른 활성탄소에 비해 높은 농도로 용출되었다. 흡착효율, 침강속도, 유해성분 용출량 등을 종합적으로 고려하여 현장 처리 적용 가능한 활성탄소는 20-60, 20-40, 2mm&down mesh 이었으며, 흡착용량을 최우선으로 판단하여 투입물량을 계산하면 최소 현장 투입 물량은 각각 0.82, 0.90, 1.28 ton/㎘ 이다.

• 한국식품과학회지
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• 제28권3호
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• pp.506-513
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• 1996

초미세분쇄한 대두피 분말을 공기분급휠속도 (ACWS, air classifying wheel speed) 10,000 rpm, 12,000 rpm 및 20,000 rpm에서 공기분급하였을 경우 회분, 단백질 및 지방은 조분획으로, 탄수화물은 미분획으로 각각 농축되었다. 식이섬유는 조분획으로 농축되었고, ACWS가 감소함에 따라 그 함량이 증가하였다. 분획별 입자크기는 ACWS가 감소함에 따라 증가하였는데 그 범위는 미분획은 $3.1{\mu}m\;to\;5.5{\mu}m$였고, 조분획은 $9.9{\mu}m\;to\;20.0{\mu}m$였으며, 그 형태는 분획에 관계없이 대부분 모서리가 있는 타원형이었다. 전반적으로 낮은 ACWS에서 높은 점도를 보였고, 보수력, 보유력 및 유화력의 경우 조분획과 미분획에 유의적인 차이가 있으나 ACWS에 따라서는 차이가 없었다. 식품응용실험 결과 대두피 분말을 10, 20, 30% 각각 대체시켜 튀김옷으로 활용하였을 때, 기름 흡수량이 대조구에 비하여 감소하였으며, 케익과 쿠키의 제조에 있어서 밀가루를 대두피 분말로 10% 수준까지 성공적으로 대체할 수 있었다.

• 상하수도학회지
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• 제20권3호
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• pp.367-375
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• 2006

Sequencing Batch Reactor (SBR) is well adopted for community wastewater treatment for its simplicity, performance and various advantageous treatment options. SBR is now drawing attention for its process modification such as coupled with membrane bioreactor, reverse osmosis or applying different media to achieve high removal efficiency. This study focused on the improved efficiency of carbon, nitrogen and phosphorous removal by applying zeolite materials called bioceramics to the SBR. Two laboratory-scale SBR units were operated in the same operating conditions - one with bioceramics called Bioceramic SBR (BCSBR) and the other without bioceramics used as control. Routine monitoring of COD, TP, $NH_3-N$, $NO_3-N$ was performed throughout this study. COD removal was about 80% to 100% and phosphorous removal was about 60% in the process whereas $NH_3-N$ removal efficiency was found to be 99.9% in the BCSBR unit. Addition of bioceramics also improved sludge characteristics such as sludge dewaterability, specific gravity and particle size. BCSBR can withstand high ammonia shock loading leading to the better treatment capacity of high ammonia containing wastewater. The cause of improved removal efficiencies within the biological reactor could be attributed to the biochemosorption mechanisms of bioceramics. Absorption/adsorption or desorption capacity of bioceramics was tested through laboratory experiments.

• 한국식품과학회지
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• 제17권6호
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• pp.522-525
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• 1985

건조된 콩우유 비지의 첨가가 두부의 품질(品質)에 어떠한 영향을 미치는지 조사하고자 제조된 두부의 부피, 견고성, 보수력 그리고 관능적 성질을 비교하였다. Acetone으로 세척하여 건조(乾燥)된 비지를 건물량 기준으로 원료(原料) 대두(大豆)에 10-30% 되게 여과된 대두 추출액에 혼합하여 두부를 제조하였을 때 부피 및 보수력(保水力)의 감소와 침입도(針入度)의 증가가 있었다. 건조비지의 혼합비율(混合比率)을 10%로 할때는 침입도(針入度)는 감소하였으나 Sag의 값이 감소함으로서 딱딱함은 오히려 증가하였고 부피의 감소는 비교적 적었다. 또한 관능적(官能的) 성질(性質)인 부서짐성과 과립성이 향상되어 10% 범위 내에서의 건조비지 혼합에 의한 두부제조의 가능성을 보여주었다. 또한 두부의 보수력(保水力) 비교를 위하여 여과지에 비결합수(非結合水)를 흡착시켜 측정함이 간편하며 비교성이 좋은 방법(方法)임이 밝혀졌다.

• Advances in materials Research
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• 제6권1호
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• pp.65-78
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• 2017

A hat section was designed and developed for maximum impact energy absorption and/or transmission under low velocity impact. Towards this, different hat sections, having material properties of thermoplastic, were modeled and investigated numerically using finite element analysis (FEA) in the range of 20-50 J impact energy. In the study it was experienced that the design configuration of hat section with curvilinear profile (HSCP) was excellent in energy attenuation capacity and for even distribution of maximum impact force around and along the hat section under low velocity impact loading. To validate the numerical findings, polypropylene copolymer (Co-PP) HSCP and low density polyethylene (LDPE) HSCP were developed and evaluated experimentally in the said impact energy range. A correlation was established between FEA and experimental test results, thereby, validating a numerical model to predict results for other thermoplastic materials under given range of impact energy. The LDPE HSCP exhibited better performance as compared to Co-PP HSCP in the said range of impact energy. The findings of this study will enable the engineers and technologists to design and develop low velocity impact resistance devices for various applications including devices to protect bone joints.

• 한국가스학회지
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• 제12권4호
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• pp.41-45
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• 2008

본 논문은 외부의 충격력을 차단하고, 충격에너지를 흡수하는 헬멧의 강도안전과 변형거동에 대한 수치적 연구를 수행한 것이다. 기존헬멧과, 보강뼈대와 주름댐퍼를 추가적으로 설치한 4개의 헬멧모델에 대한 응력 및 변형거동을 유한요소법으로 해석하였다. 헬멧의 정상부에 보강뼈대를 설치하면 헬멧의 강도 안전 향상에 유용하고, 헬멧의 하단부에 주름댐퍼를 설치하면 충격에너지 흡수효과가 우수하다는 것을 FEM 해석결과를 통해 확인할 수 있었다. 따라서 첨단헬멧을 안전하게 설계하기 위해서는 보강뼈대와 주름댐퍼를 새로운 설계요소로 고려할 것을 권장한다.

• Food Science and Biotechnology
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• 제18권4호
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• pp.889-894
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• 2009

Barley proteins are expected to have unique functional properties due to their high content of alcohol soluble protein, hordein. Since the barley proteins obtained by conventional isoelectric precipitation method cannot represent hordein fraction, barley proteins were fractionated to albumin, globulin, glutelin, and hordein with respect to extraction solvents. Functional properties and film-forming properties of solubility-fractionated barley proteins were investigated to explore their potential for human food ingredient and industrial usage. The 100 g of total barley protein comprised 5 g albumin, 23 g globulin, 45 g glutelin, and 27 g hordein. Water-binding capacities of barley protein isolates ranged from 140-183 mL water/100 g solid. Hordein showed the highest oil absorption capacity (136 mL oil/100 g), and glutelin showed the highest gelation property among the fractionated proteins. In general, the barley protein fractions formed brittle and weak films as indicated by low tensile strength (TS) and percent elongation at break (E) values. The salt-soluble globulin fraction produced film with the lowest TS value. Although films made from glutelin and hordein were dark-colored and had lower E values, they could be used as excellent barriers against water transmission.

• Asian-Australasian Journal of Animal Sciences
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• 제21권12호
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• pp.1773-1778
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• 2008

Two experiments were carried out to study the effects of corticosterone (CORT) administration on intestinal morphology and function of broilers. In both experiments, birds were randomly divided into two equal groups. One group was the control group (CTRL), and the birds were fed with a basal diet. The other was the experimental group (CORT), and the birds were fed with the basal diet plus 30 mg of CORT/kg diet. At 21 days of age, performance, morphological characteristics of intestine, D-xylose level in plasma, activities of digestive enzymes in digesta, digestibility of nutrients and 5-bromo-2-deoxyuridine (BrdUrd)-labeling index of intestinal epithelial cells were determined. CORT administration decreased feed intake, daily gain and feed conversion ratio (p<0.05). CORT also decreased duodenal and jejunal villus height (p<0.05) as well as crypt depth (p<0.05). The D-xylose level in plasma of CORT-treated broilers was lower than that of the control (p<0.05). CORT treatment caused a decrease in apparent digestibility of protein (p<0.05), whereas fat and starch apparent digestibilities were unaffected (p>0.05). CORT administration increased activities of trypsin and amylase (p<0.05), and decreased BrdUrd-labeling index of duodenal and jejunal epithelial cells (p<0.05). In conclusion, CORT administration impaired the normal morphology and absorptive capacity of the small intestine of broiler chickens.

• 산업기술연구
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• 제19권
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• pp.75-79
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• 1999

Rotary bending fatigue tests were performed to investigate the effects of 2-phase matrix structure on fatigue limit with prepared specimens in high strength ductile irons. Two types of the specimens with different microstructures have been used. Series A has sorbite and series B has bainite. Fatigue limits of both specimens are improved comparing with as cast specimen. The fatigue limit is higher in series B than in series A. The reason why the fatigue limit of series A shows inferiority to that of series B is due to the transition of micro fatigue cracks to mesocrack occurs very rapidly, so increased stress intensity factor drives the fatigue crack growth. The higher fatigue limit of series B which has bainite is caused by the ${\gamma}$ layer contained in microstructure impede the rapid growth of micro fatigue crack to mesocrack and ${\alpha}$ layer around graphite has the higher capacity for the absorption of plastic deformation energy than sorbite.

• 한국식품조리과학회지
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• 제26권6호
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• pp.772-780
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• 2010

This study investigated the quality of rice noodles containing different amounts of Allium victorialis powder. Rice noodles were prepared at ratios of 1, 3 and 5% Allium victorialis powder based on flour weight. The rice noodles containing Allium victorialis powder had higher moisture contents than that of control, whereas the levels of water binding capacity were lower. Regarding the cooking properties of the rice noodles, weight and water absorption were significantly lower in the 1, 3% Allium victorialis rice noodles compared to control. : 5% Allium victorialis rice noodle showed the highest score. Further, volume of the 5% Allium victorialis rice noodle showed the highest score. Allium victorialis rice noodles had lower L-values and a-values than those of control, and these values decreased with increasing amounts of Allium victorialis powder while the b-value increased. Sensory evaluation showed that high quality cooked noodles could be produced by 1, 3% inclusion of Allium victorialis powder. The pH of the rice noodles decreased gradually over 15 days of storage time. Rice noodles with added Allium victorialis powder had lower total and fungus plate counts than that of control during 15 days of storage.