• Proceedings of the Korean Society of Life Science Conference
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• 2000.12a
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• pp.20-26
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• 2000

호흡기계 및 소화기계에 감염된 전염성 바이러스에 대한 역학적 기초자료로 이용하고자 1999년 1월부터 12월까지 부산지역에서 분리된 전염성 바이러스의 특징과 계절적 발생추이, 환자의 성별, 연령별 발생에 대해 조사한 결과는 다음과 같다. 1. 1999년도 바이러스 가검물 2261건에서 분리한 호흡기계감염 바이러스 279건과 소화기계 감염 바이러스 83주를 분리하였으며, 이중 인플루엔자 바이러스 A형이 96주(29.6%), B형이 107주(33.0%)로 대부분을 차지하였다. 2. 1999년의 바이러스 분리의 성별 분포는 총 360명의 환자 중 179명(49.7%)의 남성 및 181명(50.3%)의 여성으로 비슷한 양상을 나타내었다. 이중 호흡기계의 경우 279명의 감염환자 중 남성이 130명(46.6%), 여성이 149명(53.4%)으로 여성의 감염율이 비교적 높았으나, 소화기계의 경우 83명의 감염환자 중 남성이 51명(61.4%), 여성이 32명(38.5%)으로 남성의 감염율이 거의 2배정도 높게 나타났다. 3. 1999년의 연령별 분포는 10세 이하의 어린이가 194명(59.9%)으로 대부분을 차지하였으며, 이중 인플루엔자 바이러스가 99명(30.6%)으로 가장 높은 감염을을 나타내었다 유행성이하선염 바이러스의 감염어린이 중에 $l1{\sim}15$세의 연령층이 15명으로(53.3%)로 가장 높게 나타났다. 4. 1999년 월별 감염율은 호흡기계 감염증 바이러스의 경우 1월부터 4월까지, 그리고 12월에 증가 추세를 보이면서 4월에 가장 높은 감염율을 나타내었다 소화기계 감염증 바이러스의 경우 9, 10, 11월을 제외한 모든 월별에 관찰되었으며, echo와 coxsackie 바이러스는 무균성 수막염 환자에서 하절기에 집중적으로 발생하였다. 동절기에 유행하는 설사 바이러스는 12월에 비교적 높은 양상을 나타내었다. 5. 인플루엔자 바이러스는 MDCK 세포에서, 아데노 바이러스와 유행성 이하선염 바이러스는 HEp-2 세포에서, 파라인플루엔자 바이러스는 Vero 세포에서, 그리고 echo, coxsackie B 바이러스와 장내 바이러스는 HEp-2, Vero, BGM 세포에서 뚜렷한 세포병변 효과를 나타내었다. 6. 분리한 바이러스는 전자현미경으로 관찰한 결과 인플루엔자 바이러스 A 형(HINI, H3N2)은 95nm, B 형은 70nm크기의 구형을 나타내었으며, 바이러스표면의 지질 이중층이 뚜렷하게 관찰되었다. 아데노 바이러스는 외피가 관찰되지 않았으며, nucleocapsid는 symmetry이고 크기는 71nm로서 바이러스 입자 표면에 icosaheral capsomer의 배열이 명확하게 관찰되었고, 파라인플루엔자 바이러스와 유행성 이하선염 바이러스는 외피가 있는 구형의 큰 viron으로180, 170nm 크기이었다. 7. Echo와 coxsackie B group 바이러스는 모두 외피가 없는 isometric 형으로 크기는 $30{\sim}45nm$ 이었고, enteric adeno 바이러스는 84nm 크기로서 외피가 없고, 입자 표면에 capsomer의 배열이 명확하게 관찰되었고, rotavirus는 크기가 70nm이며 외층 capsid 단백질과 내층 capsid 단백질이 두층으로 되어 있는 전형적인 수레바퀴 모양을 나타내었다. 이상의 결과로 보아 호흡기계 및 소화기계에 감염되는 전염성 바이러스는 연중 지속적으로 분리되고 있으며 전염성이 강하여 집단 발생은 일으키는 경우도 많고 최근 들어 유행성 이하선염과 흥역 바이러스의 발생률이 높은 추이를 나타내고 있지만 아직은 특이한 바이러스 치료제가 개발되어 있지 않았으므로 지속적인 대책과 아울러 장기적인 발생 가능에 대한 예방책을 흥보하여야 할 것으로 보이며 계속적인 바이러스성 전염병 유행예측조사 및 역학조사가 적극적으로 이루어져야 할 것으로 사료된다.

• Membrane Journal
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• v.21 no.4
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• pp.360-366
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• 2011

The effect of cross-flow velocity and transmembrane pressure (TMP) on membrane fouling was observed from pilot-scale operation of thermophilic anaerobic membrane bioreactor (AnMBR) treating food waste leachate. It was found that fouling rate was reduced significantly as cross-flow velocity increased at constant TMP mode of operation while this effectiveness was more pronounced at lower TMP. Higher TMP resulted in less permeable fouling layer possibly due to compressibility of foulant material on membrane surface. Particle sizes of membrane concentrate ranged from 10 to $100{\mu}m$, implying that shear-induced diffusion enhance back transport of these particle sizes away from the membrane effectively. From the continuous operation of AnMBR, it was confirmed that shear rate played an important role in the reduction of membrane fouling. Membrane autopsy works at the end of operation of AnMBR showed clearly that both organic and inorganic fouling were significant on membrane surface. Surface shear by cross-flow velocity was expected to be less effective to remove irreversible fouling which can be mainly caused by the adsorption of organic colloidal materials into membrane pores.

• Membrane Journal
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• v.16 no.4
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• pp.294-302
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• 2006

Silver polymer electrolytes are very promising membrane materials for the separation of olefin/paraffn mixtures. Olefin molecules are known to be transported through reversible complex formation with silver ions entrapped iii polymer matrix. However, they have poor long-term stability, which is very important fur the industrial application; the selectivity through the membrane decreases gradually with time mostly due to the reduction of silver ions ($Ag^+$) into silver nanoparticles ($Ag^0$). In this study, the stability of silver polymer electrolyte was investigated for poly(vinyl pyrrolidone) (PVP) and $AgBF_4$ system containing a surfactant, i.e. $C_{18}H_{35}(OCH_2CH_2)_{20}OH$ (Brij98) as a stabilizer. The reduction behavior of silver ions to silver nanoparticles in PVP was also investigated by atomic force microscopy (AFM) and UV-visible spectroscopy. It was found that the growth of silver nanoparticles was slower and selectivity of polymer electrolyte for propylene in propylene/propane was maintained longer time when Brij98 was added as a stabilizer.

• Journal of Advanced Marine Engineering and Technology
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• v.25 no.2
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• pp.365-374
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• 2001

Its a tendency to strengthen related international was as the importance on marine oil pollution recently becomes the issue. According to the regulation of IMO, oil discharge from ships is allowed under 15PPM only and oil filtering equipment is essential. Oily water separator of laminated plate type which is one of gravity type separator can be use as assistant equipment for the oil filtering system to meet the present IMO standard, because it fits well to process large amount of rich oil with high specific gravity. The purpose of this paper is to investigate an efficiency of oil/water separation with the characteristics of laminated plate arrangement. The analyse of oil contents for oil-water mixture were carried out in order to find an efficiency of oil/water separation and an experimental study was simultaneously carried out to investigate internal flow characteristics of separator by visualization method and PIV(Particle Image Velocimetry) measurement at three spaces of plates for 5, 10 and 15 mm with variation of inlet flow rates of $0.25m^3$/h and $0.5m^3$/h. The experimental results showed that the space of the plates acts a significant role in the separating process.

• Journal of fish pathology
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• v.19 no.1
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• pp.55-64
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• 2006

Rhabdovirus-like virus were isolated from the fry (15~30 days post hatching, dph) and rearing water of the snakehead fish Channa arga exhibiting mass mortality in spring of 2003 and 2004 in Korea. The isolates were propagated in EPC and SSN-1 cells but not replicated in FHM cells. The bullet-shaped viral particles (45×100 nm) appeared to be compact and a similar morphology to those of the rhabdoviruses in the infected EPC cells. The optimum temperature for virus replication was 20 to 25℃ but they could not replicate at 15℃. The isolates ShFRV-3 and ShFRV-5 from snakehead fish showed high pathogenicity against the fry (15 dph) and fingering (40 dph) of snakehead fish but did not in the larger size (90 dph).

• Membrane Journal
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• v.26 no.6
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• pp.421-431
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• 2016

Novel membrane technologies that harness ordered nanostructures have recently received much attention because they allow for high permeability due to their reduced flow resistance while also maintaining high selectivity due to their isoporous characteristics. In particular, the opaline structure (made from the self-assembly of colloidal particles) and its inverted form (inverse-opal) have shown strong potential for membrane applications on account of several advantages in processing and the resulting membrane properties. These include controllability over the pore size and surface functional moieties, which enable a wide range of applications ranging from size-exclusive separation to catalytically-reactive membranes. Furthermore, when combined with multiscale architecturing strategies, inverse-opal-structured membranes can be designed to have specific pores or channel structures. These materials are anticipated to be utilized for next-generation, high-performance, and high-value-added functional membranes. In this review article, various types of inverse-opal-structured membranes are reviewed and their functionalization through hierarchical structuring will be comprehensively investigated and discussed.

• Journal of the Mineralogical Society of Korea
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• v.15 no.4
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• pp.293-304
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• 2002

Wet purification process for the selective separation of montmorillonite from Gampo 13 and 35 bentonite ores was studied using physical processes such as ultrasonic scrubbing, decantation and centrifugation. Ultrasonic Scrubbing of Gampo 13 and 35 bentonite ores was revealed excellent result at 7 wt.% of slurry density and was almost finished within 30 minutes in the sample of Gampo 13 and 10 minutes in the sample of Gampo 35, respectively After decantation, approximately 52 wt.% from the bentonite of Gampo 13 and 64wt.% from the bentonite of Gampo 35 were recovered as purified products and the CEC was reached up to 119.4 meq/100 g and 124.5 meq/100 g, respectively. Particle separation by centrifugation showed that most of the impurity minerals such as quartz and feldspar were removed within the condition of 1,000 rpm.

• Membrane Journal
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• v.25 no.1
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• pp.1-6
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• 2015

It was known that the polarlized surface of silver nanoparticles could be interacted revesibly with olefin molecules for facilitated olefin transport. However, it was thought that it can be regenerated by interaction between oxide surface of AgNPs and olefin molecules because the surface of the silver nanoparticles is easily oxidized in the air. In order to investigate the effect of the silver oxide, 5 wt% AgO or $Ag_2O$ was dispersed in polymer PVP solutions and 0.005~0.02% electron acceptor as TCNQ or p-BQ were added to fabricate the separation membrane. After the addition of the electron acceptor, it was expected to improve the polarity on the surface of the silver oxide and the degree of dispersion. The characteristics of the separation membrane were identified by the gas permeance, XPS and TEM.

• Journal of the Korean Geotechnical Society
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• v.19 no.4
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• pp.179-190
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• 2003

The grout based on solution type makes it difficult to get the improvement of ground strength and the effefct of water curtain because it has lower strength and durability than suspension type. Nowadays, the technology of particle acceleration, that enhance the material permeability, such as grout based on solution type, and inexpensive grout, is being required. For these reasons, in this study, using wet milling system, we evaluated physical properties of manufactured factors such as water-cement ratio of particles before being milled, optimum milling capacity by controlling milling time and rpm, viscosity of materials, permeation coefficient, and unconfined compressive strength. Also, using micro wet milling apparatus which could manufacture ordinary Portland cement and high speed shear mix which could forcefully separate conglomerate particles in situ, we performed electrical resistivity investigation and falling head permeability tests to analyze differences of grouting effects. From these results, we found that the permeability of the applied equipment was much superior, and in the case of using high speed shear mixer, particles of grout material were well separated.

• Journal of Korean Society of Water and Wastewater
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• v.18 no.2
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• pp.254-269
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• 2004

Polysilicato-iron coagulant (PSI) is receiving attention in Japan as a substitute for aluminum-based coagulants. In the first part of this article, coagulation, sedimentation and filtration experiments were carried out using kaolin clay particles as the turbidizing material and four types of PSI with various molar ratios of polysilicic acid to ferric chloride (Si/Fe ratio). Results demonstrate that use of a PSI with a high Si/Fe ratio can cause a more dramatic decrease in treated water turbidity but a higher suction time ratio (STR) than when PACl is used. However, optimization by increasing the rapid agitation strength GR is found to greatly improve the STR. In addition, the series of filtration experiments verified that optimization of GR is greatly effective in controlling rapid increases in filter head loss, and also formation of a thin aging layer in the upper part of the filter bed by slow-start filtration is effective in improving filtered water turbidity over the entire filtration process. The second part of this article describes two innovative filtration techniques to increase the particle separation efficiency; (1) coagulant-coated filter medium by enhancing the electrical potential of the surface of the filter medium, and (2) coagulant dosing in influent by controlling the electrical potential of particles entering the filter layer. From the results of the various filtration experiments using a pilot plant, these two techniques were found to be very effective to reduce the effluent water turbidity from the start to the end of a filter run. Moreover, in the filtration experiments using these two methods simultaneously, higher removal efficiency of approximately 3-log (99.7%) was realized, resulting that the finished water turbidity was accordingly reduced to 0.004mg/L.