• Preventive Nutrition and Food Science
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• 제8권2호
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• pp.154-157
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• 2003

A peptide inhibiting HIV-1 pretense was isolated from the hydrolysate of manila clam (Ruditapes philippinarum) proteins digested with thermolysin. The peptide was purified by using membrane filtration, gel permeation chromatography, ion exchange chromatography, and reverse phase HPLC, The amino acid sequence of the peptide was determined to be Ile-Tyr-Glu-Gly. This tetrapeptide sequence exists in some proteins of Physarum polycephalum and Mycobacterium smegmatis. Chemically synthesized Ile-Tyr-Glu-Gly showed the $IC_{50}$/ value of 22.3 $\mu$M.

• 생명과학회지
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• 제10권2호
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• pp.140-149
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• 2000

In order to utilize marine processing waste which would normally be discarded, cod liver protein was hydrolysed by ${\alpha}$-chymotrysin, and the hydrolysate was investigated for the new angiotensin I converting enzyme (ACE) inhibitor. Thy hydrolysate was separated into three major types, with molecular weight cut-off (MWCO) values less than 10 kDa, 5 kDa and 1 kDa of ultrafiltration membranes, respectively. ACE inhibitory peptides were isolated from the fractions passed through MWCO 1 kDa membrane, and purified by using ion-exchange chromatography on a SP-Sephadex C-25 column, gel filtration on a Sephadex G-15 column, and HPLC on an ODS column. The purity was identified with capillary electrophoresis. The amino acid sequences of two peptides were Met-Ile-Pro-Pro-Tyr-Tyr (IC50=10.9 ${\mu}$M) and Gly-Leu-Arg-Asn-Gly-Ile (IC50=35.0 ${\mu}$M)

• Preventive Nutrition and Food Science
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• 제8권1호
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• pp.66-69
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• 2003

An angiotensin converting enzyme (ACE) inhibitory peptide was isolated and purified from the hydrolysates of duck meat protein. Duck meat protein was hydrolyzed using trypsin at 37$^{\circ}C$ for 2 hrs. An ACE inhibitory peptide was purified using membrane filtration, anion exchange chromatography, gel permeation chromatography, fast protein liquid chromatography, normal phase HPLC. The purified inhibitory peptide was identified to be a tetrapeptide, Glu-Asp-Leu-Glu having $IC_{50}$/ value of 85.9 $\mu$M.

• 한국분말야금학회:학술대회논문집
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• 한국분말야금학회 2006년도 Extended Abstracts of 2006 POWDER METALLURGY World Congress Part 1
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• pp.599-600
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• 2006

This paper described the state of art of porous metal materials, the typical manufacturing technologies and performances of sintered metal porous materials, with emphasis on the recent research achievements of CISRI in development of porous metal materials. High performance porous metal materials, such as metallic membrane, sub-micron asymmetric composite porous metal, large dimensional and structure complicated porous metal aeration cones and tube, metallic catalytic filter elements, lotus-type porous materials, etc, have been developed. Their applications in energy industry, petrochemical industry, clean coal process and other industrial fields were introduced and discussed.

• 상하수도학회지
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• 제27권5호
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• pp.555-560
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• 2013

A cost analysis method for pretreament processes of a large scale seawater desalination plant was considered using a cost estimation model, WaTER (Water Treatment Estimation Routine). This model is based on cost functions of U.S. EPA to conduct economic analysis of water treatment facilities. A virtual seawater desalination plant which has pretreatment production capacity of $100,000m^3$ per day was chosen as a model plant. Dual media filtration and microfiltration systems were compared as pretreatment process, and the following reverse osmosis process was modeled. As a result, microfiltration showed a price competitiveness in condition of operating with reverse osmosis process by reducing the loads of water treatment and membrane cleaning despite it's high annual cost.

• 한국소성가공학회:학술대회논문집
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• 한국소성가공학회 2005년도 춘계학술대회 논문집
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• pp.237-240
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• 2005

The demand of micro electrical mechanical system (MEMS) bio/chemical sensor is rapidly increasing. To prevent the contamination of sensing area, a filtration system is required in on-chip total analyzing MEMS bio/chemical sensor. A nano-filter was mainly applied in some application detecting submicron feature size bio/chemical products such as bacteria, fungi and so on. We suggested a simple nano-filter fabrication process based on replication process. The mother pattern was fabricated by holographic lithography and reactive ion etching process, and the replication process was carried out using polymer mold and UV-imprinting process. Finally the nano-filter is obtained after removing the replicated part of metal deposited replica. In this study, as a practical example of the suggested process, a nano-dot array was replicated to fabricate nano-filter fur bacteria sensor application.

• Childhood Kidney Diseases
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• 제27권1호
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• pp.19-25
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• 2023

Proteinuria is an important risk factor for renal and cardiovascular disease. It is associated with a risk for glomerulonephritis, chronic kidney disease, and end-stage renal disease. Therefore, if persistent proteinuria is detected, kidney biopsy is considered to diagnose and treat the underlying disease. Recently, variants in the cubilin (CUBN) gene, which is associated with albuminuria, have been reported. This gene encodes cubilin, a membrane glycoprotein receptor expressed in the renal proximal tubules. Cubilin is a component of the megalin and cubilin-amnionless complex that mediates albumin reabsorption into the proximal tubules through endocytosis. A defect in cubilin leads to a reduction in albumin reuptake, resulting in albumin-dominant proteinuria. Although numerous controversies exist, several reports suggest that cubilin defects lead to proteinuria with a high portion of albuminuria but may not impair renal filtration function. If albuminuria due to reduced cubilin function is confirmed as a benign condition, we can consider using genetic studies to detect CUBN mutations in patients with proteinuria and they may not require any treatment or kidney biopsy. Here, we review recent papers on CUBN mutations and discuss the prognosis and management of individuals with this mutation.

• 대한환경공학회지
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• 제38권8호
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• pp.444-451
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• 2016

기존에는 lab-scale 연구에서 이론식을 기초로 막오염 모델식을 구성하였지만, 이러한 모델식은 여과, 역세, 배출이 연속적으로 이루어지는 실규모 현장에 적용하기에는 적합하지 않았다. 본 연구는 실제로 인천시 G-정수사업소에서 발생되는 배출수 처리를 위해 연속자동 운전되고 있는 침지막 공정을 대상으로 진행되었다. 정유량 조건에서 막오염 관리지표를 막간차압(Trans-Membrane Pressure, TMP)으로 결정하고 침지막 공정의 주요 운전변수인 총 투과유량과 조 내 SS농도를 독립변수로 하여 TMP의 시계열 예측을 시도하고 예측 가능성 및 적용성을 평가하였다. 유전자알고리즘을 이용한 시계열 예측모형을 구성한 결과, TMP 예측값이 펄스주기 형태와 경시적인 증가 추세 두 가지를 모두 반영하고 있어서 만족할 만한 결과가 나왔다. 두 번의 검증 결과, 선형회귀 방식으로 TMP 실측치와 예측치의 상관성(유의성)을 나타내면 각각 $r^2=0.721$, $r^2=0.928$ 수준이다. 본 연구에서는 하절기 자료를 활용하여 모델링 작업을 수행하였지만 추후에 연속자료가 더 쌓이면 같은 절차로 모델링 작업을 반복해서 더 높은 신뢰도의 예측모형을 구성할 수 있고 이를 실제 현장에 적용하여 2~3일 정도의 단기예측을 수행한다면 실제로 막공정을 에너지 효율적으로 운영하는데 도움이 될 것으로 사료된다.

• 멤브레인
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• 제8권4호
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• pp.203-209
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• 1998

에멀젼형 절삭유(Caltex, Trusol) 수용액을 공칭 세공크기가 0.22 $\mu$m 인 Millipore사의 GVHP 막과 0.2$\mu$m인 SUS 관형막(Mott 사)이 설치된 dead-end 및 십자형흐름 정밀여과 시스템으로 각각 분리하였다. 오일입자의 분포는 0.07 내지 0.22$\mu$m의 분포이었다. 투과유속을 예측하기 위하여 cake 여과모델 (CFM)과 standard pore blocking 모델(SPBM)을 적용하였다. Dead-end 시스템에서 0.01 vol% 절삭유 수용액을 400 rpm으로 교반시켜 투과시킬 경우, 100 kPa 이하에서는 CFM 이 투과유곡을 잘 나타내었으나, 150 kPa 이상에서는 SPBM을 적용할 수 있었다. 운전압력을 60에서 200 kPa로 갑자기 증가시키면 분리막 표면에 형성된 오일층이 파괴되고, 다시 60 kPa로 감소시킬 때 반복하여 오일층이 형성됨을 알 수 있었다. 투과기구가 CFM에서 SPBM 으로 전환되는 이른바 임계압력을 추정하였으며, dead-end system에서는 약 100 kPa이었다. Reynolds 수가 7080인 십자형흐름 시스템에서 농도를 0.01에서 0.03 vol%로 증가시키면 입계압력이 약 100에서 150 kPa로 증가하였다.

• 대한환경공학회지
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• 제34권9호
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• pp.637-643
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• 2012

본 연구에서는 300 kDa 공경의 세라믹막을 이용하여 재이용 원수인 하수 2차 방류수를 처리하여 가역 및 비가역 막오염비율을 연구하였다. 이를 위하여 운전조건인 막간차압을 변화시킬 때의 각 막오염을 수치적으로 계산하고 F-EEM과 SEC분석을 시행하였다. 또한 탁도, TOC 및 UV254를 측정하여 수질의 안정성을 평가하였다. 막간차압이 낮을수록 비가역 막오염에서 가역 막오염으로의 형성이 증가하였으며, 이는 주로 분자량이 큰 단백질 성분으로 인한 것으로 나타났다. 또한 하수 2차 처리수에는 다양한 분자량의 오염물이 함유되어 있으나 상대적으로 0.5 kDa 이하의 작은 분자량을 가지는 오염물이 가장 많았으며, 그 다음으로는 12 kDa 이상의 물질이 많았다. 300 kDa의 세라믹막은 주로 6 kDa 이상의 물질을 제거하였으며, 막간차압이 낮을수록 12 kDa 이상의 고분자 물질과 1 kDa 이하 물질이 가역 막오염으로 형성되는 것으로 나타났다.