• Membrane Journal
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• v.28 no.2
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• pp.96-104
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• 2018

With the rapid increase in seawater desalination, the importance of boron rejection is rising. This study was conducted to investigate the effect of hydrophilic compounds on surface modification to maximize water flux and increase boron rejection. First, polyamide active layer was fabricated by interfacial polymerization of polysulfone ultrafiltration membrane with M-phenylenediamine (MPD) and trimesoyl chloride (TMC) to obtain Control polyamide membrane. Next, D-gluconic acid (DGCA) and D-gluconic acid sodium salt (DGCA-Na) were synthesized with glutaraldehyde (GA) and hydrochloric acid (HCl) by modifying the surface of Control polyamide membrane. XPS analysis was carried out for the surface analysis of the synthesized membrane, and it was confirmed that the reaction of surface with DGCA and DGCA-Na compounds was performed. Also, FE-SEM and AFM analysis were performed for morphology measurement, and polyamide active layer formation and surface roughness were confirmed. In the case of water flux, the membrane fabricated by the surface modification had a value of 10 GFD or less. However, the boron rejection of the membranes synthesized with DGCA and DGCA-Na compounds were 94.38% and 94.64%, respectively, which were 12.03 %p and 12.29 %p larger than the Control polyamide membrane, respectively.

• Journal of Food Hygiene and Safety
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• v.31 no.5
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• pp.342-348
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• 2016

The objective of this study was to compare the change of S. Enteritidis with S. Typhimurium populations in liquid egg products. S. Enteritidis or S. Typhimurium was inoculated into egg white and egg yolk and stored at 8, 10, 15, 25, and $35^{\circ}C$, respectively. In egg white, no growth of S. Enteritidis and S. Typhimurium was observed at 8, 10, 15, and $35^{\circ}C$, while both S. Enteritidis and S. Typhimurium in egg white stored grew more than 1 log CFU/ml after 50 hours storage at $25^{\circ}C$. In egg yolk, there was no growth of S. Enteritidis and S. Typhimurium at $8^{\circ}C$ but growth of both strains was observed at 10, 15, 25, and $35^{\circ}C$. Since growth of S. Enteritidis and S. Typhimurium was only observed in egg yolk, primary growth models for both strains were developed using modified Gompertz equation and then secondary models for lag time (LT), specific growth rate (SGR), and maximum population density (MPD) were developed as a function of temperature. At all temperatures, more rapid growth of S. Enteritidis than S. Typhimurium was observed in egg yolk, indicating the greater risk of S. Enteritidis than S. Typhimurium in egg products. In conclusion, the results indicate that temperature control less than $8^{\circ}C$ is very important to ensure safety of liquid egg products, especially liquid egg yolk.

• Journal of the Korean Society of Food Science and Nutrition
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• v.38 no.11
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• pp.1595-1599
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• 2009

Ginseng is one of the most well known medicinal plant in East Asia with many bioactivities. The purpose of this study was to evaluate the quality properties of cookies added with different concentrations (0, 1, 3, and 5%) of ginseng powder by molecular press dehydration (MPD) method. MPD was known to be an excellent tool for keeping taste and flavor without any loss of original materials. The results indicated no significant difference in the density of cookie dough with different concentrations of ginseng powder. The L color value was decreased and the a color values were increased with increasing concentrations of ginseng powder (p<0.05). However, there was no significant difference in the b values. Spread factor of cookie was not significantly different between 1% and 3%, but decreased at 5% (p<0.05). The hardness of cookies was significantly increased as ginseng powder concentration increased. The result of sensory score showed that cookie added with 1% ginseng powder had higher color, sweetness, overall acceptability scores than other samples. As a result of this study, quality of cookies with added 1% ginseng powder were the most suitable in terms of its color, texture, and sensory properties.

• Korean Journal of Food Science and Technology
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• v.37 no.5
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• pp.850-855
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• 2005

Model was developed to predict the growth of Listeria monocytogenes in raw pork. Experiment condition for model development was full 5-by-7 factorial arrangements of temperature (0, 5, 10, 15, and $20^{\circ}C$) and time (0, 1, 2, 3, 18, 48, and 120 hr). Gompertz values A, C, B, and M, and growth kinetics, exponential growth rate (EGR), generation time (GT), lag phase duration (LPD), and maximum population density (MPD) were calculated based on growth increased data. GT and LPD values gradually decreased, whereas EGR value gradually increased with increasing temperature. Response surface analysis (RSA) was carried out using Gompertz B and M values, to formulate equation with temperature being main control factor. This equation was applied to Gompertz equation. Experimental and predictive values for GT, LPD, and EGR, compared using the model, showed no significant differences (p<0.01). Proposed model could be used to predict growth of microorganisms for exposure assessment of MRA, thereby allowing more informed decision-making on potential regulatory actions of microorganisms in raw pork.

• Journal of Oral Medicine and Pain
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• v.14 no.1
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• pp.113-121
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• 1989

In this study, 94 patients with temporomandibular disorders were interviewed to evaluate the effect of the treatment they received at the department of Oral diagnosis and oral Medicine in Seoul national university Hospital. The treatment administered to the patient were patient education, relaxation procedures, physical therapy, occlusal splint therapy and selective grinding of teeth. The following results were disclosed : 1. 97.9% of the patients reported no pain or considerably less pain than they had reported at their first visits to the department. 2. 89.3% of the patients thought that the treatment provided was either complete or considerably successful. 3. TMJ and facial pain was resolved within average 3.0 months 4. Of the 70 patients who previously reported having jaw joint sound, 34 patients (48.6%) no longer reported int. 5. Of the 48 patients who previously reported having headache regularly, 3 patients (68.8%) no longer reported headache regularly. 6. Of the 66 patients who previously reported having masticatory muscle pain, 41 patients (62.1%) no longer reported masticatory muscle pain. 7. Analysis of the data did not disclose a subgroup or factor, such as age, the stage of internal derangement, capsulitis, bruxism, MPD, duration of symptoms, that could be correlated with the reduction of pain or the patient's perception of success of treatment.

• Proceedings of the KIEE Conference
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• 2011.07a
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• pp.1610-1611
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• 2011

실선로 전력 케이블의 부분방전 측정은 주위 전력설비의 신호들이 혼합되면 정확한 부분방전 진단이 어려운 면이 있다. 본 논문에서는 15kV급 EPR 난연 케이블을 대상으로 거리에 따른 부분방전 신호를 검출 및 감쇄 정도 확인 시험을 통하여 발생 위치 추정 기준을 마련하고자 한다. 이를 위해 길이 500m의 EPR 난연 케이블을 제작하여 모의 선로를 구성하였고, IEC60270에 적합한 Calibrator를 이용하여 신호를 인가한 후 HFCT 센서를 사용하여 일정한 거리를 두고 방전 신호를 검출하고, Techimp사(社)의 PDBASE와 OMICRON사(社)의 MPD600을 이용하여 부분방전 신호를 분류하였다. 전압 인가 지점에서 단계적인 거리증가에 따른 부분방전 신호 감쇄 현상 및 일정 길이(300[m])에 대한 주입 신호별 감도 측정을 분석하였다. 본 논문의 시험대상인 15kV급 EPR 난연 케이블은 원자력 발전소의 배전선으로 사용하기 위해 제작된 것으로, 포설 후 절연체 내에 B/D가 발생했다고 가정했을 때, PD신호의 검출 및 대략적인 위치의 추정은 안전을 최우선시 하는 원자력 발전 및 배전 부문에서 주요한 문제로 부각 될 것이다.

• Journal of the Korean Applied Science and Technology
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• v.26 no.4
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• pp.428-433
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• 2009

Cellulose triacetate (CTA) was prepared from cotton linter and pulps which contain various contents of $\alpha$-cellulose. CTA which contains 2.8 of degree of substitution (DS) and 222 of degree of polymerization (DP) was obtained from V-81 pulp under the heterogeneous system. The DS was measured by the titration method, and the DP was obtained by measurement of viscosity. FT-IR spectometer (FT-IR 6300, JASCO) was used to analyze the chemical structure of raw materials and cellulose triacetate, and X-ray diffractometer (X-pert MPD PW3040, Philips) was used to confirm the crystal structure and to calculate the relative crystallinity index (RCI). As $\alpha$-cellulose content in pulp increased, the acetylation yield increased. Besides with a kind of pulp, it contains insoluble residue which was mainly formed due to the formation of glucomannan triacetate and xylan diacetate during the esterification.

• Proceedings of the Korean Society of Postharvest Science and Technology of Agricultural Products Conference
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• 2003.04a
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• pp.142.2-142
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• 2003

본 연구에서는 풋고추, 대파와 깻잎에 물리적인 장해를 주지 않고 저장성을 향상시킬 수 있는 열처리 조건을 설정하고, 열처리한 채소의 MAP에 적합한 포장재를 검색하기 위한 실험을 수행하였다. 대파를 55$^{\circ}C$ 온수에서 1분 침지하고, 풋고추와 깻잎은 5$0^{\circ}C$ 온수에서 10초와 5초 각각 침지하면 저장 중 관능적 품질이 비열처리한 대조구보다 우수하게 나타났다. 열처리한 채소의 호흡속도는 비열처리 채소에 비하여 30~45%정도 상승하였다. 열처리 채소의 MAP에 적합한 포장재를 검색하기 위하여 기체 투과도가 서로 다른 포장재 LDPE, CPP, PD900, MPD2055, SM60에 열처리한 채소를 포장한 후 1$0^{\circ}C$에서 4주간 저장을 하였다. 포장 표면에 5mm의 구멍을 뚫은 대조구와 핀홀이 있는 SM60은 저장 2주 이후 부터 중량감소가 심하게 일어났다. 깻잎은 포장내부의 $CO_2$ 농도가 높게 유지되는 CPP에 포장할 때, 저장 2주부터 $CO_2$ 장해로 인하여 표면의 갈변과 연화가 심하게 일어났으며, 풋고추는 저장 3주부터 표면의 색상이 약간 붉은 색을 나타내기 시작하였다. 열처리 풋고추와 깻잎을 MDPE 포장에 저장을 하면 각각 저장 4주와 3주까지는 시장품질의 한계선으로 신선도가 유지되었다. 그러나 대파는 포장 내부의 $CO_2$ 농도가 높은 CPP에 포장할 경우 발근이 억제되며 저장 4주까지 시장품질 이상을 유지하였다.

• The Korea Journal of Herbology
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• v.20 no.2
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• pp.17-26
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• 2005

Objectives : The study has been undertaken to scrutinize the results of Halloysitum Rubrum before and after physical and chemical manipulation. Methods : I used X-rays diffracted analysis system(Phillips X'Pert - MPD System) on condition of 40Kv, Anode of Cu Ka to grasp the compositions of crude Halloysitum Rubrums which have been from here and there after pulverization them below 200 mesh. X-rays fluorescence analysis system have been used to check the chief elements content of the ore on condition of 40Kv, 95mA. ICP-MS analysis system(Perkin Elmer, Elan 6100)have been used after a micro-elements and a heavy metals take advantage of mixed acid were dissolved completely. Results : The compositions of the ore Halloysitum Rubrum are composed of large amount of Halloysite and Kaolinite, and small amount of Hematite, Alum, quartzite. The chief elements content of the ore Halloysitum Rubrum are composed of Al and Si. A heavy metals in Halloysitum Rubrum are As, Cd, Cr, Cu, Pb, Zn, etc. As and Zn's amounts was lessen after physical and chemical manipulation Halloysitum Rubrum are decreased at $400^{\circ}C\;and\;450-500^{\circ}C$ each by heat analysis system. Conclusion : Results of this study show that Halloysitum Rubrum can be used in a diverse ways to treat many kinds of disease.

• Macromolecular Research
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• v.11 no.3
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• pp.157-162
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• 2003

6FDA-based polyimides were prepared from the thermal imidization reaction of 6FDA with diamines of BAPAF, DAP, and DABA having a polar group of hydroxyL or carboxyl. Properties of the dense polyimide membranes were characterized and their gas permeation properties for H$_2$, $CO_2$, $O_2$, $N_2$, and CH$_4$ were investigated. Permeabilities, diffusion coefficients and diffusivity selectivities of polar group-containing polyimide membranes including 6FDA-BAPAF, 6FDA-DAP, and 6FDA-DABA polymer for the gases did not change largely. The separation properties of 6FDA-TrMPD polyimide membrane used as a reference polymer were compared with those of the polyimide membranes mentioned above. It was found that the polyimides of 6FDA-BAPAF, 6FDA-DAP, and 6FDA-DABA, which were soluble in alcohol or/and 2-methoxyethanol, could be applicable to the preparation of a dense composite membrane by dip-coating method.