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A New Analytical Method for the $Eu^{+3}$ and $Tb^{+3}$ Ions Using the Luminescence Enhancement by the Treatment of o-Phenanthroline on the Nylon Membrane (Nylon Membrane Filter에서의 발광증폭을 이용한 $Eu^{+3}$$Tb^{+3}$ 이온의 극미량 분석법)

  • An, Seong-Hee;Lee, Byung-Min;Park, Jong-Mok;Kim, Hai-Dong;Jeong, Hyuk
    • Journal of the Korean Chemical Society
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    • v.39 no.9
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    • pp.705-714
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    • 1995
  • A new analytical luminescence method for the Eu+3 and Tb+3 ions was studied using the luminescence enhancement by the treatment of the o-phenanthroline on the nylon membrane. Compared to the specific emission intensities of the ions in aqueous(or ethanol) solution, if the aqueous ion is spotted on the nylon membrane, the luminescence intensities were extremely enhanced. There was additional enhancement effect of the luminescence intensities of the ions on the nylon membrane, if the ion on the nylon membrane is treated with o-phenanthroline. Based on the luminescence enhancement, the detection limits were lowered by more than 7 order of magnitude compared to that of solution sample, and also lowered by about 1 order of magnitude compared to that of previous TLC method. The dynamic ranges and correlation coefficients of the calibration curves near the detection limit were 2∼3 order and ∼0.99, respectively. It was also shown that the luminescence intensity was in its maximum when the ion on the nylon is treated with ∼4 mole ratio of o-phenanthroline. The energy-transfer mechanism was explained for the theoretical background of the luminescence enhancement.

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Contents of Heavy Metals (Hg, Pb, Cd, Cu) and Risk Assessment in Commercial Cephalopods (유통 두족류의 중금속(Hg, Pb, Cd, Cu) 함량과 위해성 평가)

  • Kim, Su-Un;Hwang, Young-Ok;Park, Ae-Sook;Park, Young-Ae;Ham, Hee-Jin;Choi, Sung-Min;Kim, Jung-Hun
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.40 no.4
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    • pp.606-612
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    • 2011
  • The purpose of this study was to investigate certain heavy metals (Hg, Pb, Cd, Cu) in 144 samples of cephalopods, to identify weekly heavy metal intakes and to evaluate potential health risks. The average concentrations in the arm, expressed in mg/kg, were: Hg 0.017 (less than the limit of detection (LOD) to 0.059), Pb 0.024 (less than the LOD to 0.092), Cd 0.030 (less than the LOD to 0.627) and Cu 2.536 (less than the LOD to 5.837). The average concentration in the internal organs, expressed in mg/kg, were: Hg 0.063 (from 0.008 to 0.543), Pb 0.579 (less than the LOD to 2.344), Cd 15.200 (from 0.654 to 75.29) and Cu 201.706 (from 2.412 to 856.4). Heavy metal concentrations were higher in the organs than in the arm. Of the four heavy metals, the ratio of internal organs to arm was highest for cadmium. The weekly intakes of Hg, Pb, Cd and Cu from Octopus minor were 0.2%, 0.08%, 0.20% and 0.00%, respectively from the arm, and 1.0%, 0.96%, 92.28% and 0.05% from the internal organs as compared to PTWI (provisional tolerable weekly intakes) established by the FAO/WHO Expert Committee for Food Safety Evaluation.

Modelling Spatial Variation of Housevalue Determinants (주택가격 결정인자의 공간적 다양성 모델링)

  • Kang Youngok
    • Journal of the Korean Geographical Society
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    • v.39 no.6 s.105
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    • pp.907-921
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    • 2004
  • Lots of characteristics such as dwelling, neighborhood, and accessibility characteristics affect to the housevalue. Many researches have been done to identify values of each characteristic using hedonic technique. However, there is a limit to identify interaction of each characteristic and variation of each characteristic among the accessibility context. This paper has implemented the Expansion Method research paradigm to model the housevalue determination process in the city of Seoul. The findings of this paper have revealed the presence of contextual variations in the housevalue determination process. The initial model for housevalue reveals that as $F_1$ increases (i.e., larger the number of rooms/bathrooms, larger parking space) and/or $F_2$ increases (i.e., higher owner occupied housing units, higher apartment housing units) and/or $F_3$ increases, (i.e., higher the ratio of higher than college graduated households, 8 school zone, older housing units) the estimated housevalue increases. However, the above relationships drift across their respective contexts. The houses which have negative $F_1$ value, the housevalue does not fluctuate according to the distance to the city center or subcenters. However, the houses which have positive $F_1$ value, the closer to the subcenters or shorter to the river, the higher the estimated housevalues. On the other hand, in areas far from the subcenters, the estimated housevalues does not fluctuate much according to the corresponding $F_2$ level. In areas close to the subcenters, the estimated housevalues vary tremendously according to the $F_2$ value. In the residual analysis, it is revealed that large apartment which are located in Kangnam, IchongDong, MokDong are underestimated. This paper has contributed to our understanding of the housevalue determination process by providing an alternative conceptualization to the traditional approach.

Phase Changes of Soil-Cement Mixture Using Fall Cone and Heat of Hydration (Fall cone과 수화열을 이용한 흙-시멘트 혼합물의 상 변화 연구)

  • Kim Jae-Hyung;Won Jeong-Yun;Kim Sung-Pil;Chang Pyoung-Wuck
    • Journal of the Korean Geotechnical Society
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    • v.20 no.9
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    • pp.25-32
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    • 2004
  • Some amount of cements can be added into the soil with high water content to improve the engineering properties. In such a case, it is difficult to predict and figure out the phase changes of the soil-cement mixture which is closely associated with workability of the soil-cement mixture. Changes in heat of hydration and hardness of the cement pastes are known to provide the useful information about the phase changes of the soil-cement mixtures. In this study, heat of hydration and cone penetration depth were measured from the specimens of cement paste and 3 soil-cement mixtures. From the experimental results, it was found that the phase changes of the soil-cement mixtures are the same as those of cement paste, and that shear strength of the mixtures abruptly increases when the heat of hydration is minimum. Initial setting time of the mixtures coincides with the state when fall cone penetration depth was 1.0 mm and it is defined as plastic limit of the mixtures. Initial setting time of the mixtures is retarded as soil/cement ratio is increased. Measurements of heat of hydration and fall cone apparatus could be the useful tools to predict the phase changes of tile soil-cement mixtures.

Consolidation Characteristics & Consolidation Period of Dredged Soil by Considering Change of Strain and Stratum Thickness (변형률과 층 두께의 변화를 고려한 준설점토의 압밀특성과 압밀기간)

  • Cheong Gyu-Hyang;Kim Young-Nam;Ju Jae-Woo
    • Journal of the Korean Geotechnical Society
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    • v.20 no.9
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    • pp.105-114
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    • 2004
  • Consolidation characteristics have been investigated by using Rowe cell consolidation tester for dredged soil, which is more than two times as much as the liquid limit. To examine the effects of variation of water content on consolidation characteristic, tests were carried out varying the initial water content from $100\%\;to\;150\%.$ The results were compared with the consolidation characteristics of remolded clay. The test results showed that the hither the initial water content of dredged clay was, the more noticeable the non-linear behavior of e-log P curves occurred. The variation of the gradient was apparent to load stage 40kPa and became less apparent after load stage 80kPa on the e-log P curves. Ratio of compression index stayed within the range suggested by Mesri and variation of initial water content has hardly influenced the coefficient of consolidation. On the contrary, it was found that the magnitude of consolidation load affects the vertical coefficient of consolidation. The variation of stratum thickness during consolidation processing needs to be taken into consideration since hydraulic fill would go through a much larger scale strain than land soil when it is subject to a load. In this study, the consolidation period considering the variation of stratum thickness was analyzed and the results were compared with those of existing consolidation studies which did not consider the variation of stratum thickness. According to the results of the study, the consolidation period of the ground with a larger strain was calculated more close to observed value in case of Mikasa theory which takes the variation of stratum thickness into consideration.

A Study on the Atomizing Mechanism for the Swirl Nozzle (와권(渦卷) 노즐의 무화기구(霧化機構)에 관(關)한 연구(硏究))

  • Lee, Sang Woo;Sakai, Jun;Ishihara, Akira
    • Korean Journal of Agricultural Science
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    • v.14 no.1
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    • pp.81-97
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    • 1987
  • Two nozzles with different size (Figure 2) were particularly designed to supply air through the swirl core into the central part of the liquid stream in the same parallel direction to produce a well-mixed air and water in the whirl chamber as spray liquid in bubble formation. Atomization was attempted to improve by using both the preliminary break-up process with less viscosity and less surface tension in the whirl chamber and the effects of increased frequency of the band of drops with the raised ambient air density in front of the nozzle orifice. The volumetric ratio between spray liquid and air on four levels was used to investigate the effects of air as a component of the mixture on atomization. The results of the experiment were summarized as follows; Droplet size became progressively finer as the operating pressure was increased in the range of $0.70kg/cm^2$ to $6.33kg/cm^2$, which was similar to the previous works. The new atomizing mechanism so-called 'air-center nozzle' gave a narrower range in droplet size distribution with smaller volumetric median diameter (VMD) than that of the existing spray system at a given pressure, which showed the possibility of improvement of atomization in a certain limit. The volumetric median diameter produced by the new atomizing mechanism was decreased from the central region toward the exterior edges across the spray pattern.

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The Result of Ventilating Bronchoscopy for the Air Way Foreign Bodies (Ventilating bronchoscopy로 치유시도된 기도이물의 치료성과)

  • 우훈영;고건성;이희배;윤태현;안회영;백만기
    • Proceedings of the KOR-BRONCHOESO Conference
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    • 1978.06a
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    • pp.4.3-5
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    • 1978
  • The foreign bodies in air way require the emergent managements in the otolaryngolagic field, and if the diagnosis and treatment were delayed, unexperted catastrophic situations may occur. The authors had analysed the airway foreign bodies of 50 cases which had been ventilating bronchoscopy. 1. In sex distribution, male to female ratio was 2.8 : 1. 2. In the age incidence, 58% were 1∼5 yrs. 3. Frequent symptoms, were coughing (68%), dyspnea (52%) and cyanosis (18%) in the oder. 4. The significant foreign body histories were noticed in 33 cases (66%). The initial misdignosis were 28%, and af which 57.1% were URI 5. In auscultation, decreased breathing sounds were noticed in 46%, wheezing were 24% and 26% were with in normal limit. 6, In duration af lodgement, 68% were removed within 24 hours. 7. Tracheostomy were performed in 24%, and foreign bodies were removed by ventilating bronchoscope in 72%. 8. The foreign bodies were vegetable (46%), metal (28%), plastic (18%) and fish bone (8%). 9. The prevalent site of foreign body were right main bronchus, left main bronchus, and trachea in the order mentioned.

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A Statistical Study of the Foreign Bodies in the Air Passages (기도 이물의 임상통계적 고찰)

  • 신기철;이동명;김진영;김홍기
    • Proceedings of the KOR-BRONCHOESO Conference
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    • 1981.05a
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    • pp.4.1-4
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    • 1981
  • The statistical study was done on 74 cases of foreign bodies in the air passages, who visited the department of otolaryngology of SNUH during recent 5 years from 1975 to 1980. The result was as follows, 1) Of the total 74 cases, 55 cases were male and 18 cases were female. The ratio between male and female was 3 : 1. 41.8% of all-cases were under 2 years of age, 75.5% were under 3 years, and 83.6% were under 5 years. 2) Major symptoms on visit were dyspnea, cough, cyanosis. No significant symptoms was noted in 6.7%. Initial physical findings were coarse breathing sound, decreased breathing sound, and stridor. No abnormal physical findings were noted in 10.8%. 3) 48.6% of total cases visited hospital within 24 hours. There was one case who visited hospital over 2 years later. 4) Initial simple chest film showed atelectasis in 25.0%, emphysema in 32.8%, definite foreign body shadow in 17.2% and within normal limit in 17.2%. 5) 60.8% of total cases were vegetables, 15.5% were metals, 16.2% were fish bone, and 2.7 % were others. 6) Vegetables were most frequent foreign bodies in the cases under 5 years of age. 7) 40.5% of total cases were lodged in the right main bronchus, 31.0% were in the left main bronchus, 9.8% were in trachea and 6.7% were in multiple sites, 8) Foreign bodies were removed by ventilating bronchoscopy in 82.3%, by tracheostomy only in 2.7%, by tracheal suction in 2.7%, by spontaneous removal in 1.3%, by thorachotomy in 5.4% and 5.4% of total cases were expired.

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Development of Sandwich ELISA for the Detection of Mackerel in Processed Foods (가공식품 중 고등어의 검출을 위한 ELISA의 개발)

  • Shon, Dong-Hwa;Kim, Mi-Hye
    • Korean Journal of Food Science and Technology
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    • v.44 no.1
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    • pp.1-7
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    • 2012
  • There have been few studies related to ELISA for mackerel. In this study we developed a sandwich ELISA for mackerel in processed foods using rabbit polyclonal antibodies against mackerel parvalbumin, the major allergen of mackerel and heat-stable protein. The parvalbumin was purified by ammonium sulfate precipitation and Sephadex G-50 column chromatography. From the standard ELISA curves, the detection limit of parvalbumin was 3 ng/mL and the detection range of mackerel was 5-5,000 ${mu}g/mL$. We further investigated the cross-reactivity of the antibodies toward mackerel, mackerel pike, salmon, flatfish, armorclad rockfish, cod fish, squid, shrimp, blue crab, and lobster. The antibodies were specific for mackerel only. The mean assay recoveries in cooked cream soup, baby food, sausage, and sauce spiked with 0.01 to 0.3% mackerel were 104, 101, 54, and 0%, respectively. In sample tests of 16 commercial items, the qualitative coincidence ratio of assay result and indication was 75%.

Estimation of Local Change in Hydrometeorologic Environment due to Dam Construction (댐 건설로 인한 국지 수문기상환경의 변화 추정)

  • Yoo, Chul-Sang;Ahn, Jae-Hyun;Kang, Sung-Kyu;Kim, Kee-Wook;Yoon, Yong-Nam
    • Journal of Environmental Policy
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    • v.4 no.1
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    • pp.21-38
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    • 2005
  • In this study, a model for analyzing the spatial effect of large dam reservoirs on local hydrometeorology was developed, and then actually applied to the Seomjingang Dam, Soyanggang Dam, Andong Dam, and Chungju Dam. The application included the analysis of land use using the satellite images to derive the change in albedo before and after the dam construction. Summarizing the modeling procedure and its application results are as follows. (1) The change in albedo was found to be closely related with the size of the dam, also the spatial limit of albedo change were estimated to be 10-20km for the Seomjingang Dam, 40km for the Soyanggang Dam, 20-30km for the Andong Dam, and 50km for the Chungju Dam. (2) The change in the coefficient of recycle (ratio of internal supply of moisture to the total available moisture) was found to be big within the narrow boundary of the. dam, but become smaller as the boundary becomes larger. (3) The correlation between the albedo and. coefficient of recycle was found high. Thus, it could be concluded that the change in land use due to dam construction has much effect on the moisture circulation structure. (4) The spatial range of hydrometeorogic effect was compared with the water surface area of dam reservoir. The result showed that the spatial range sensitively increased up to $50km^2$ of water surface area.

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