• 한국지하수토양환경학회:학술대회논문집
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• 한국지하수토양환경학회 2002년도 총회 및 춘계학술발표회
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• pp.209-212
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• 2002

Main radionuclides of the soil waste stored in Korea Atomic Energy Research Institute are Co-60 and Cs-137. Moisture content of soil is 12%, pH of soil is 5.8, and content of organic matter is 2.2 %. Radioactive concentrations of the soil particle size of which is less than 0.063mm and soil in the drum surface of which is more than radiation dose rate 0.05mR/hr are higher. Meanwhile, radioactive concentration of soil in the drum surface of which is less than radiation dose rate 0.02 mR/hr are mostly lower. On using the mixing solution of ammonium sulfate and citric acid, 62% Co was removed from soil and 41% Cs was removed. Also, on using the mixing solution of ammonium nitrate and citric acid, 61% Co was removed from soil and 39% Cs was removed, and on using the mixing solution of ammonium potassium oxalate, 36% Co was removed and only 3% Cs was removed. And on using only water, removal efficiency is less than 5%.

• 한국환경과학회지
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• 제15권9호
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• pp.829-834
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• 2006

This research aims to investigate the behavior of organic matter that causes bacterial re-growth and the formation of disinfectant by-products such as THM in water treatment, and to optimize conditions for a more efficient and conventional water facility. THM removed 51 % and 12 % through coagulation/sedimentation and filtration using a selected conventional system. In this experiment, the removal ratio of DOC was highest at 68 % when the Gt value was 42,000 and lowest at 41 % when the Gt value was 30,000. 77-84 % of total DOC was removed during coagulation/sedimentation, and 15-23 % was removed during filtration. When Gt values were between 30,000 and 66,000, over 50 % of high molecular matter above 10 K during coagulation/sedimentation was removed. Turbidity removed 98 % when the G1 value was 66,000. As the Gt value increased, the turbidity removal ratio increased. Turbidity removed over 20 % during the filtration process.

• 대한기관식도과학회지
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• 제7권1호
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• pp.14-18
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• 2001

Background and Objectives： Vegetable Foreign bodies (VFB) in the bronchial tree may be complicated by fragmentation, slippage and impaction during the removal with forceps. This study is to evaluate the safety and efficacy for the technique of removing VFB from the bronchial tree in infants and early childhood using Fogarty balloon catheter. Materials and methods : The subjects consisted of 18 infants and early childhood (7-22 months old) with VFB in the bronchial tree from January 1991 through October 1998. The authors first attempted removal of VFB with forceps and if that failed, removed VFB with Fogarty arterial embolectomy catheter under the ventilating bronchoscopy and general anesthesia. Results: We removed 6 VFB with forceps. could not remove anymore, and so removed 12 VFB with Fogarty catheter. In 8 VFB of less than 24 hours, we could remove 6 VFB with forceps and 2 VFB which could not be removed with forceps were removed with Fogarty catheter. In 10 VFB of more than 24 hours, we could not remove with forceps and removed with Fogarty catheter. Conclusions : VFB in the bronchial tree of infants and early childhood can usually be removed with forceps. But we think that Fogarty balloon catheter technique is a easy, safe method for the removal of bronchial VFB of more than 24 hours, fragmentation, impaction, lower bronchus and too round or slippery to remove with forceps in infants and early childhood.

• Journal of Photoscience
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• 제12권1호
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• pp.17-23
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• 2005

Application of a new photocatalyst has been attempted to improve the efficiency and rates of photocatalytic degradation of azo dyes by using a model dye such as Methyl Orange. As a new photocatalyst, $TiO_2$ encapsulated EFAL-removed zeolite Y ($TiO_2$ /EFAL-removed zeolite Y) has been synthesized by ion-exchange in the mixture of EFAL-removed zeolite Y with 0.05 M aqueous [$(NH_4)_2 TiO(C_2O_4)_2.H_2O$] [$TiO(C_2O_4)_2.H_2O$]. This new photocatalyst has been characterized by measuring XRD, IR and reflectance absorption spectra as well as ICP analysis, and it was found that the framework structure of $TiO_2$ /EFAL-removed zeolite Y is not changed by removing the extra-framework aluminum (EFAL) from the normal zeolite Y and the $TiO_2$ inside the photocatalyst exists in the form of $(TiO^{2+})_n$ nanoclusters. Based on the ICP analysis, the Si/Al ratio of the $TiO_2$ /EFAL-removed zeolite Y and the weight of $TiO_2$ were determined to be 23 and 0.061g in 1.0g photocatalyst, respectively. It was also found that adsorption of the azo dye in the $TiO_2$ /EFAL-removed zeolite is very effective (about 80 % of the substrate used). This efficient adsorption contributes to the synergistic photocatalytic activities of the $TiO_2$ /EFAL-removed zeolite by minimizing the required flux diffusion of the substrate. Thus, the photocatalytic reduction of methyl orange (MO) was found to be 8 times more effective in the presence of $TiO_2$ /EFAL-removed zeolite Y than in the presence of $TiO_2$ /normal zeolite Y. Furthermore, the photocatalytic reduction of MO by using 1.0 g of the $TiO_2$ /EFAL-removed zeolite Y containing 0.061g of $TiO_2$ is much faster than that carried out by using 1.0 g of Degussa P-25.

• Journal of Biosystems Engineering
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• 제33권6호
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• pp.453-461
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• 2008

This study was conducted to develop a root-removed splice grafting system for cucurbitaceous vegetables, mainly watermelon and cucumber seedlings, for the seedlings factories where currently most of seedlings grafting works are carried out by manual works. The major results of the study are as follows. The dimensions of rootstocks and scions, except cotyledon width, of root- removed splice grafting of watermelon and cucumber were shown to be varied within the 2.5-fold range. The growth status of seedlings were not consistent in terms of cotyledon sprouting direction and angle which were considered as one of the important factors for in root-removed splice grafting. The grafting work of root-removed splice for grafted watermelon and cucumber could be divided by four sub-operations: seedling supplying, cutting, clipping and potting, while a part or all root of the rootstock was removed in the seedlings supplying operation. The cutting angles of the rootstock and scion were $34-45^{\circ}$ and $20-45^{\circ}$, respectively, while the stem length of the scion varied from 6 mm to 12 mm. The splices of rootstock and scion were heaped up in parallel and then fixed by a clip. It indicated that the ideal grafting system, adopting conventional grafting processes of seedlings specifications as well as conventionally manual root-removed splice grafting method, performed very well for seedlings gripping and transporting, supplying clip, clipping and discharging grafted seedlings while workers supplied seedlings to the semi-automatical system.

• 해양환경안전학회:학술대회논문집
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• 해양환경안전학회 2003년도 춘계학술발표회
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• pp.205-209
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• 2003

The various pretreatment processes were evaluated for removal of oil pollutants with weathered oil contaminated seawater in a reverse osmosis desalination process. Weathered oil contaminated seawater was made by biodegradation and photooxidation with oil containing seawater. Coagulation, ultrafiltration, advanced oxidation processes and granular activated carbon filtration was used with pretreatment for dissolved organic carbon. Crude oil was removed but. weathered oil contaminated seawater was not removed by biodegradation and coagulation. DOC and E260 was removed with about 20 % and 40 % by membrane filter of cut off molecular weight 500. So, the most of dissolved organic carbon in weathered oil contaminated seawater was revealed that molecular weight was lower than 500. It is difficult to remove DOC in weathered oil contaminated seawater by advanced oxidation processes treatment, but, E260 was removed more high. However, DOC in weathered oil contaminated seawater was easily adsorbed to GAC. It is revealed that DOC was removed by adsorption.

• 한국구조물진단유지관리공학회 논문집
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• 제5권1호
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• pp.188-194
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• 2001

A reinforced concrete structure is complex structure that works as one body with bonding role of steel bar and concrete. The bonding action between steel bar and concrete makes possible the compound structure. The transmission of mutual strength of the steel bar with concrete in structure is determined by the bonding characteristic of steel bar and concrete surface. But the efficiency of bonding characteristic of steel bar is Questionable by the corrosion cause by the delay construction term, the wrong management, etc. So this study investigate bonding characteristic of reinforced concrete using pull-out test method which steel bar removed rust and the principal variables of this study are concrete compression strength and the degree of corrosion. The result showed that bonding strength tend to increase when removed rust of steel bar whereas it tend to decrease when not removed rust.

• 대한기관식도과학회:학술대회논문집
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• 대한기관식도과학회 1977년도 제11차 학술대회연제 순서 및 초록
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• pp.8.3-8
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• 1977

기도이물은 식도이물과 더불어 타질환에 비해 그리 드문것이 아니며 이비후과 영역에서 매우 중요한 위치를 차지하고 있 뿐만 아니라 이에 대한 보고도 많다. 특히 기도이물의 종류 및 위치에 따라 다르지만 기도의 폐색을 일으켜 호흡장애 실식으로 생명의 위험을 주는 경우도 있으므로 주의깊게 관찰하지 않으면 안되는 질식의 하나라고 하겠다. 또한 기도이물은 증례에 따라 연령의 차이가 있고 이물의 종류와 형태도 다양 할 뿐 아니라 그 개재부위도 달라서 항상 낙관할 수는 없는 것이다. 이에 저자들은 근간에 결험한 기도이물로 비교적흥미가 있다고 생각되는 5례를 경험하였기에 보고하는 바이다.

• 상하수도학회지
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• 제22권5호
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• pp.523-529
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• 2008

Algal blooms in a local eutrophic lake often produces the musty and earthy taste & odor problems. Since the odor causing compounds(OCCs) including geosmin and 2-MIB have their own volatility, the OCCs can be removed from water by air stripping methods. Removal of TON(threshold odor number) as an index for OCCs could be fitted well with the first order equations($R^2=0.9$ above), where the air stripping coefficient of TON, k was in the range between 0.0055 and 0.0097 according to the aeration time. k within 30min aeration tests was 0.0097, while it was 0.0055 where the aeration time extended to 150min. With 15 mg/L of PAC, removal of TON was not simulated with 1st order equation within 30min aeration. Within 30min aeration, OCCs rather than geosmin and/or 2-MIB could be removed easily by air stripping or PAC adsorption, while OCCs such as geosmin and/or 2-MIB could be removed slowly by air stripping after 30min aeration. Geosmin and 2-MIB were not readily removed by air stripping(k of them were 0.0018~0.0047 and 0.0018~0.0034, respectively at different air flow rates). Geosmin could be removed by air stripping a little better than 2-MIB.

• 한국가축번식학회지
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• 제15권2호
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• pp.103-107
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• 1991

This study was carried out to investigate the survival rate in vitro culture after frozen-thawed to used DMSO(dimethyl sulfoxide), glycerol and ethylene glycol of cryoprotective agents at the zona pellucida removed and encased into alien bisected embryo of the mouse early embryos. The results obtained from this study were as follows : 1. The survival rate of in vitro culture after frozen-thawed to used cryoprotective agents of three kinds at the zona pellucida removed bisected morula was 46.6%, 35.8% and 27.3%, total or mean were 36.6%, respectively. 2. The survival rate of in vitro culture after frozen-thawed to used cryoprotective agents of three kinds at the encased into alien bisected morula was 70.6%, 65.3% and 66.4%, total or mean were 67.4%, respectively. 3. The survival rate of in vitro culture after frozen-thawed to used cryoprotective agents of three kinds at the zona pellucida removed bisected blastocysts was 50.4%, 36.7% and 30.4%, total of mean were 39.2%, respectively. 4. The survival rate of in vitro culture after frozen-thawed to used cryoprotective agents of three kinds at the encased into alien bisected blastocysts was 71.1%, 66.7% and 63.9%, total or mean were 67.2%, respectively.