• Korean Membrane Journal
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• 제7권1호
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• pp.19-27
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• 2005

PP hollow fiber membrane was hydrophilized by EVOH dip coating followed by low temperature plasma treatment and UV irradiation. EVOH coating attained high water flux without any prewetting but its stability did not guaranteed at high water permeation rate. At high water permeation rate, water flux declined gradually due to swelling and delamination of the EVOH coating layer causing pore blocking effect. However, plasma treatment reduces the swelling, which suppress delamination of the EVOH coating layer from PP support result in relieving the flux decline. Also, UV irradiation helped the crosslinking of the EVOH coating layer to enhance the performance at low water permeation rate. FT-IR and ESCA analyses reveal that EVOH dip coating performed homogeneously through not only membrane surface but also matrix. Thermogram of EVOH film modified plasma treatment and W irradiation show that crosslinking density of EVOH layer increased. Chemical modification by plasma treatment and UV irradiation stabilized the hydrophilic coating layer to increase the critical flux of the submerged membrane.

• 펄프종이기술
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• 제34권4호
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• pp.30-36
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• 2002

This research was conducted to investigate the feasibility of using deinked pulp of white ledger(DIP) for the manufacture of high quality premium tissue. The three types of tissues were prepared using the softener treated bleached DIP, softener treated mixed pulp of unbleached DIP and virgin pulp, and untreated mixed pulp of bleached DIP and virgin pulp, respectively, and their tensile index. softness, and brightness were measured and compared. The bulk and surface softness increased only slightly by the addition of softener(0.2% mineral oil) into the bleached DIP. The tensile index was decreased by 15∼30%, and the brightness was the range of 86% to 87% ISO. The softener(0.2∼0.8% mineral oil or dialkyl imidazoline) treatment of mixed pulp of unbleached DIP and virgin pulp Improved the bulk and surface of tissue considerably. However, the brightness was low as 85% ISO or below. Although the softness of the tissue made from bleached DIP blended with virgin pulp was the lowest among three types of tissues evaluated, its tensile index was the highest and brightness was 87∼88% ISO. Based on the results, it may be predicted that the bleached DIP blended with virgin pulp is the best raw material for the manufacture of high quality premium tissue if softener treatment is applied to mixed pulp, because the softness can be improved by the addition of softener. In general, the softness of tissue was improved with the increase in the amount of softener: However, the tensile index inversely proportional to the amount of softener added. Dialkyl imidazoline was more effective than mineral oil with respect to the improvement in softness, even though the loss in tensile index was severe with the treatment of dialkyl imidazoline.

• 한국해양환경ㆍ에너지학회지
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• 제6권1호
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• pp.44-59
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• 2003

육상축양장 배출수 처리에 의한 대상해역의 수질개선 효과를 산정하기 위하여 생태계 모델시뮬레이션을 행하였다 가막만에서의 잔차류 패턴은 해수가 출입하는 북쪽의 협수도에서는 남향류가 강한 것으로 나타났으며, 남쪽 만구부에서는 동향류가 우세하며 시계방향의 환류가 강하게 나타났다. 9개 정점 표층에서의 DIP, DIN과 COD 농도의 지점별 계산치와 관측치를 비교한 결과 DIP의 경우 상대오차는 평균 14.3％, DIN은 평균 25.8％ 그리고 COD는 평균 14.4％였다. DIP, DIN과 COD 모두 오염부하의 영향이 큰 만의 북서쪽에서 높은 농도를 나타내었다. 육상축양장 배출수의 오존처리 시스템 처리효율을 DIP 90％, DIN 80％ 그리고 COD 60％로 적용하여 시뮬레이션 한 결과 DIP의 경우는 9개 정점에서 34.4~54.0％ 범위로 평균 46.4％의 수질 개선효과가 나타났으며, DIN의 수질 개선효과는 0.4~25.4％ 범위로 평균 8.4％로 나타났다. 그리고 COD는 만 전체적으로 농도가 감소하여 수질환경기준 I등급 영역이 확장되었으며, 9개 정점에서 15.6~29.4％ 범위로 평균 22.7％의 수질 개선효과가 나타났다.

• 한국표면공학회지
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• 제44권5호
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• pp.220-225
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• 2011

304 stainless steel plate was colored by hot dip and electrochemical treatment in a solution containing sulphuric and chromic acids. In the process, treatment variables such as operating time and methode were changed. The surface characteristics that changed by the treatment of the samples such as surface composition, oxide film thickness, color, surface roughness and reflectivity were studied. Surface composition was varied as follows. Fe was decreased, but Cr and O were increased. Ni was increased until 20 min, but reveals decreasing tendency as time passed after that. These means the surface film becomes chrome rich oxide phase as the treatment times increase. The thickness of film was about 220 nm at 30 min by dip treatment and it reduced as the treatment times increased. On the other hand, the thickness was about 150 nm at 10 min by electrochemical method and it doesn't increased with time. Surface color changed from metallic white of the base plate to gray, black, red, and green-blue, gradually, as the treating time increased. The reflectivity of colored surface measured by UVVIS-NIR spectrophotometer was reduced from max 38% of basis metal to min 3.5%.

• 한국해양환경ㆍ에너지학회지
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• 제6권4호
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• pp.37-44
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• 2003

목포항 해양수질개선에 대한 목포하수처리장 가동의 기여도를 평가하고 목포하수처리장 가동 후에 목포항에 유입하는 오염부하의 변화를 산정하기 위하여, 하수처리장 가동 전인 1997년 여론부터 1998년 봄까지의 건조기에 육지로부터 목포항에 유입하는 오염부하를 조사하고 목포항 주변의 하천들과 처리장 유출수의 계절별 유량 및 수질을 기초로 하여 유입오염부하를 산정하였다. 또한 하수처리장 가동 후인 1998년 겨울부터 1999년 볼까지 목포항에 유입하는 오염부하를 조사하고 목포하수처리장의 유입수 및 유출수의 오염부하를 산정하였다. 하수 처리장의 처리율은 화학적산소요구량(COD)이 약 49%, 총부유성고형물(TSS)이 약 76%, 휘박성부유물(VSS)이 약 79%, 총질소(T-N)가 약 3%, 용존무기인(DIP)이 약 7%, 총인(T-P)이 약 29%, 용존무기질소(DIN)가 약 -32%를 보였다. 하수처리장 가동으로 인한 목포항 내항수역 유입오염부하 변화율은 COD가 약 56%, TSS가 약 78%, VSS가 약 84%, DM이 약 45%, T-N이 약 22%, T-P가 약 34%, DIP가 약 -14%를 보였다. 목포항 전역으로 유입하는 총오염부하의 감소에 대한 하수처리장 가동의 기여율은 COD가 약 3%, TSS가 약 3%, VSS가 약 5%, DIP가 약 1%, T-P가 약 3%, DIN이 약 -1%로 나타났다.

• Journal of Ginseng Research
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• 제29권2호
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• pp.71-79
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• 2005

In vitro studies using detached inflorescences with peduncles were conducted to investigate flower abscission agents in North American ginseng (Panax quinquefolius L.). Of the nine compounds studied only three, ammonium thiosulphate (ATS), abscisic acid (ABA) and ethephon induced abscission. Anilazine, benzyladenine, carbaryl, gibberellic acid, napthaleneacetic acid and thidiazuron did not induce abscission. ATS dip treatments did not induce abscission but the spray treatments induced $60.5\%$ abscission at $1500\;mg{\cdot}L^{-1}$ and $33.1\%$ at $3000\;mg{\cdot}L^{-1}$. Severe chlorophyll loss occurred on all inflorescences treated with ATS. Both ABA dip treatments and a $250\;{\mu}mol{\cdot}L^{-1}$ spray treatment caused abscission $(40\%)$ without adverse effects, and timing of ABA application was important. Because ABA was only significant in the dip treatments, ABA may not be a practical option for field use on ginseng. Ethephon sprays induced more abscission as the season progressed and as the concentration increased. As the dip concentrations of ethephon increased, the abscission rate decreased and the health of the inflorescences declined. The $1500\;mg{\cdot}L^{-1}$ spray of ethephon gave consistent abscission results over the glowing season with little phytotoxicity. Treatment with the competitive ethylene inhibitor 1-methylcy-clopropene (1-MCP) suggested that flower abscission was due to the liberation of ethylene from the breakdown of ethephon.

• 전기학회논문지
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• 제58권11호
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• pp.2214-2218
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• 2009

Dye-sensitized solar cell (DSC) has been considered as a possible alternative to current silicon based p-n junction photovoltaic devices due to its advantages of high efficiency, simple fabrication process and low production cost. Numerous researches for high efficient DSC in the various fields are under way even now. Among them, the compact layer, which prevents the back electron transfer between transparent conductive oxides and the redox electrolyte, is fabricated by various methods such as a ZnO dip-coating, $TiCl_4$ dip-coating, and Ti sputtering. In this study, we tried to fabricate the $TiO_2$ compact layer by the spin-coating method using aqueous $TiCl_4$ solution. The effect of the spin-coating method was checked as compared with conventional dip-coating method. As a result, DSC with a spin-coated compact layer had 33.4% and 6% better efficiency than standard DSC and DSC with a dip-coated compact layer.

• 청정기술
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• 제7권1호
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• pp.65-74
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• 2001

본 연구는 디젤엔진에서 배출되는 NOx환원용 촉매로서 산화반응에서 우수한 활성을 나타내고 있는 페롭스카이트상의 $LaCoO_3$을 sol-gel 공정을 이용하여 촉매코팅용액을 제조한 후, 이를 기존의 dip-coating방법보다 코팅시간, 코팅량, NO-CO 산화 환원 반응에 있어서 경제적이고 효율적인 modified dip-coating방법을 이용하여 촉매코팅필터를 제조하고 이를 후처리장치에 부착함으로써 디젤엔진에서 배출되는 배가스를 효과적으로 제거시키고자 한다. 실험결과, modified dip-coating방법이 기존의 dip-coating방법에 비해서 코팅에 소요되는 용액량이 8.3배 코팅시간 83.3배 단축되었으며, 코팅량은 2~3배정도 커지고, NO-CO 산화 환원 반응성도 1.1~1.8배 가량 증가하였다. 그리고 코팅점도는 $0.006202kg{\cdot}m/sec$을 이용하여 코팅횟수 2회, 코팅량은 88.56mg/g에서 우수한 반응을 보였다. 또한 세라믹 필터의 셀수에 있어서는 200 CPSI가 적절함을 확인할 수 있다.

• 해양환경안전학회지
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• 제8권2호
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• pp.39-44
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• 2002

In order to study the change of pollution loads flowing into Mokpo harbour after the operation of Mokpo Municipal Sewage Treatment Plant (MMSTP) and to evaluate the contribution of MMSTP operation to the improvement of marine water quality of Mokpo harbour, the pollution loads flowing into Mokpo harbour from land in dry weather were surveyed and estimated on the bases of the seasonal flow rates and the seasonal water qualities of streams and effluents located around Mokpo harbour from summer, 1997 to spring, 1998 before the operation of MMSTP, and the pollution loads of the inflow and the effluent of MMSTP were also surveyed and estimated from winter, 1998 to spring, 1999 after the operation of MMSTP. The treatment rates of MMSTP were shown to be about 49% in COD, 76% in TSS, 79% in VSS, 3% in T-N, 7% in DIP, 29% in T-P and -32% in DIN. The change rates of pollution loads flowing into the inner harbour of Mokpo due to the operation of MMSTP were shown to be about 56% In COD, 78% in TSS, 84% in VSS, 45% in DIN, 22% in T-N, 34% in T-P and -14% in DIP. The contribution rates of MMSTP operation to the reduction of total pollution loads flowing into the entire Mokpo harbour were found to be about 3% in COD, 3% in 755,5% in VSS,1% in DIP, 3% in T-P and -1% in DIN.

• 한국세라믹학회지
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• 제34권7호
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• pp.747-757
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• 1997

ZSM-5 zeolite composite membranes have been synthesized from a silica sol solution containing TPABr as an organic template by the dip-coating and the pressurized-coating hydrothermal treatment techniques. The CO2 separation efficiency of synthesized composite membranes was also investigated. The permeation mechanism of CO2 through ZSM-5 membranses was the surface diffusion, and that of N2, O2, and He gases was Knudsen diffusion or activated diffusion depending on the synthetic method of membranes and the measurement temperature. The CO2/N2 separation factor of the membrane prepared by the dip-coating hydrothermal treatment was 2.5 at about 12$0^{\circ}C$, while the ZSM-5 composite membrane synthesized by the pressurized-coating hydrothermal treatment technique showed the CO2/N2 separation factor of 9.0 at room temperature higher than that ever reported in the literature.