• 지질공학
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• 제10권3호
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• pp.247-261
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• 2000

본 연구에서는 부산 지하수의 오염현황과 그 특성을 파악하기 위하여, pH, TS, KMnO$_4$소비량, Cl, SO$_4$, NO$_3$-N 등에 대한 지구통계학적 분석을 실시하였다. 각 성분의 평균치는 pH가 7.2, TS는 336.4mg/$\ell$, KMnO$_4$ 소비량은 2.3mg/$\ell$, Cl은 44.3mg/$\ell$, SO$_4$는 36.0mg/$\ell$, NO$_3$-N은 4.6mg/$\ell$이다. pH의 음용수 기준치 초과 비율은 0.34%, TS는 2.27%, KMnO$_4$소비량은 1.55%, Cl은 1.59%, SO$_4$는 0.57%, 그리고 NO$_3$-N은 3.7%이다. 따라서 성분별로 비교해 볼 때, pH의 음용수 기준치 초과비율이 가장 적고, NO$_3$-N의 초과비율이 가장 크다. NO$_3$-N이 가장 큰 이유는 부산지역이 도심지이기 때문에 생활하수나 자동차 배기가스에 의해 지하수가 많이 오염되어 있기 때문이다. 지구통계학적 분석기법인 정규크리깅을 이용하여 작성된 각 성분들의 등치선도 분석결과 오염에 관련된 높은 값들은 대부분 내륙에서 나타나고 있으며, 해안가에서는 일부 지역에서 산발적으로 나타나고 있다. 해수 침입과 직접 관련된 Cl 및 SO$_4$ 이온의 등치선도에서도 해안가의 특정 지점에서만 국부적으로 높은 값을 보여주고 있다. 또한 Cl 및 SO$_4$ 이온의 등치선도상에서 부산에 발달된 2개의 단층대(일광단층, 동래단층)와 관련된 방향성을 검토한 결과 특별한 연관성을 찾을 수 없었다. 따라서 부산지역이 해안가에 위치하고 있지만 지질특성상 전 해안선에 걸쳐 해수침입이 내륙쪽으로 깊이 발생되고 있지 않은 것으로 보인다. 부산지하수 오염의 주 원인은 해수에 의한 영향보다는 내륙에서 생활하수나 기타원인(자동차 배기가스, 오염된 하천수, 공장폐수, 폐기물 매립지의 침출수 등)에 의한 오염이 훨씬 큰 것으로 판단된다.

• 한국전기전자재료학회:학술대회논문집
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• 한국전기전자재료학회 2008년도 하계학술대회 논문집 Vol.9
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• pp.91-91
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• 2008

$SnO_2-B_2O_3-P_2O_5$ system were prepared by melt-quenching technique in the compositional series containing 50, 55 aod 60mol.% of $SnO_2$. A large glass-forming region was found at the phosphate side of the ternary system with homogeneous glasses containing up to 5-25mol.% of $B_2O_3$. For these glasses, thermal expansion coeffient($\alpha$), glass transition temperature(Tg), and glass softening temperature(Ts), were determined. The values a decrease with increasing $B_2O_3$ content, while Tg and Ts increased. The reason for the observed changes is local structure of the glasses. Local structure of the glasses was investigated by Raman and FT-IR measurements, suggesting that the number of bridging oxygens decreased whereas the non-bridging oxygen concentration increased with increasing $SnO_2$ content in the glasses.

• Bulletin of the Korean Chemical Society
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• 제17권3호
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• pp.234-238
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• 1996

Second-order rate constants have been measured spectrophotometrically for the reaction of p-nitrophenyl acetate (PNPA) with morpholine, piperazine and piperidine in MeCN-H2O mixtures of varying compositions. The rate of the present aminolysis decreases upon additions of MeCN into H2O up to near 30-40 mole % MeCN and remains nearly constant upon further additions of MeCN. The reaction of PNPA with anionic nucleophiles, such as HO-, p-chlorophenoxide and butane-2,3-dione monoximate, has also exhibited two distinguishable reactivity zones. However, the reactivity trend for the anionic nucleophiles is quite different from the one obtained for the amine system, e.g. an initial rate decrease in the H2O-rich region followed by an increasing rate trend upon further additions of MeCN in the MeCN-rich region. The rate behaviors shown by the amine system in the MeCN-rich and by the anionic system in the H2O-rich region are unexpected based on the Hughes-Ingold rules. The present unusual rate trends have been attributed to changes in the solvent structure and pKa of the nucleophiles upon the addition of MeCN into H2O. The effect of solvent appears to be more significant for the TS than the GS, and the TS structure is considered to become tighter in the higher MeCN concentration.

• Journal of Nutrition and Health
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• 제35권9호
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• pp.943-951
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• 2002

This study was designed to investigate the effects of iron supplementation and nutrition education on the iron status and anemia of high school girls. The subjects resided in Ulsan city in Korea and were already diagnosed as having anemia or iron deficiency. Over a period of three months, one iron tablet (80 mg Fe as ferrous sulfate/day) was administered to the iron deficient subjects and two tablets (160 mg Fe as ferrous sulfate/day) were administered to the anemia subjects. The average height and weight of anemia subjects were 161.24 $\pm$ 4.50 cm and 50.87 $\pm$ 5.86 kg, respectively. The average BMI (kg/$m^2$ )was 19.58 $\pm$ 2.03 and the PIBW(percent ideal body weight) were 92.52 $\pm$ 9.84%. Except for vitamin A and vitamin C intakes, the intake levels of all other nutrients were below the RDA. Total calorie intakes of anemia subjects were 73.5% of RDA. The iron intakes of subjects from food were 69. 1% of RDA and the Ca intakes were 59.1% of RDA. The basal hemoglobin(Hb) concentration of anemia subjects averaged 10.77 $\pm$ 1.33 g/dl, and this increased significantly (p < 0.001) to 12.12 $\pm$ 1.08 g/dl, after iron supplementation. The basal ferritin, and transferrin saturations ｛TS (%)｝of anemia subjects were 12.51 $\pm$ 15.19 ng/$m\ell$ and 8.43 $\pm$ 7.56%, respectively, and these significantly increased to 20.59 $\pm$ 22.39 ng/$m\ell$ and 15.56 $\pm$ 12.87%, respectively. The level of total iron binding protein (TIBC) significantly decreased from the initial 486.80 $\pm$ 70.16 $\mu\textrm{g}$/dl to 417.86 $\pm$ 67.73 $\mu\textrm{g}$/dl (p < 0.001) after iron supplementation. For the iron deficiency subjects, the ferritin, iron and TS(%) levels were increased significantly (p < 0.001) and the TIBC levels were significantly (p <0.001) decreased after iron supplementation. Anemia symptoms such as 'Feeling blue (p<0.05)', 'Decreased ability to concentrate (p<0.001)' and 'Poor memory (p<0.05)' improved significantly after iron supplementation in the anemia subjects. The number of tablets administered was positively correlated with changes in serum hemoglobin (t=0.194, p< 0.01), serum ferritin (t=0.181, p<0.01), TS(%) (t=0.141, p<0.05), and hematocrit (t=0.254, p<0.01), and was negatively correlated with changes in TIBC (t=-0.143. p<0.05) and red cell distribution width (RDW, t=-0.140, p<0.05). In conclusion, daily iron supplementation was effective in improving the iron status and reducing symptoms of anemia in high school girls. (Korean J Nutrition 35 (9) : 943~951,2002)

• 한국생물공학회:학술대회논문집
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• 한국생물공학회 2005년도 생물공학의 동향(XVII)
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• pp.266-269
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• 2005

반응조의 유입수 CODcr농도를 $75000{\sim}95000mg/L$로 운전하였을 경우 유출수 CODcr농도는 $14000{\sim}19000mg/L$로서, 제거율은 $75{\sim}85%$로 나타났다. 고온소화$(45{\pm}2^{\circ}C)$로 운전한 결과 유입수 pH는 $4.2{\sim}4.5,$ 유출수의 pH는 $6.8{\sim}7.2$를 유지하였다. TS(총고형물질)와 VS(휘발성고형물질)의 유입수를 단계적으로 각각 $2.94{\sim}5.09%$와 $2.98{\sim}5.01%$로 유지할 경우, 유출수는 단계적으로 각각 $0.65{\sim}1.1%$와 $0.6{\sim}0.8%$였다. 유출수의 TS, VS의 제거율은 각각 78, 85%이었다. $CH_4$발생량은 0.28 $m^3-CH_4/kg-VS$이었다.

• Corrosion Science and Technology
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• 제5권5호
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• pp.168-172
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• 2006

Alloy 600 having a superior resistance to a corrosion is used as a steam generator tubing in nuclear power plants. In spite of its high corrosion resistance, there are many tubings which experience corrosion problems such as a SCC under the high temperature and high pressure environments of nuclear power plants. The Alloy 600 tubing can be repaired by using a Ni electroplating having an excellent SCC resistance. In order to carry out a successful Ni electrodeposition inside a steam generator tubing, the effects of various parameters on the material properties of the electrodeposit should be elucidated. Hence this work deals with the effects of an applied current density, duty cycle($T_{on}/(T_{on}+T_{off})$) of a pulse current, bath temperature and solution pH on the material properties of Ni electrodeposit obtained from a Ni sulphamate bath by analyzing the current efficiency, potentiodynamic curve, hardness and stress-strain curve. Hardness, YS(yield strength) and TS(tensile strength) decreased whereas the elongation increased as the applied current density increased. This was thought to be by a concentration depletion at the interface of the electrodeposit/solution, and a fractional decrease of the hydrogen reduction reaction. As the duty cycle increased, the hardness, YS and TS decreased while the elongation increased. During an off time at a high duty cycle, the concentration depletion could not be recovered sufficiently enough to induce a coarse grain sized electrodeposit. With an increase of the solution temperature and pH, the YS and TS increased while the elongation decreased. The experimental results of the hardness and the stress-strain curves can be supplemented by the results of the potentiodynamic curve.

• 대한지역사회영양학회지
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• 제6권5호
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• pp.726-733
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• 2001

This study was designed to investigate the effect of iron supplementation on the iron nutritional status and anemia of high school girls in Korea. One hundred thirty-five female students residing in Ulian metropolitan city in Korea diagnosed as having anemia or iron deficiency participated in this study. One or two tablets of iron medicine(80-160 mg Fe as ferrous sulfate/day) were administered to all participants for 3 months. Subjects were evaluated with a questionaire, measurement of hematological indices before and after iron supplementation. The average height and weight of respondents were 161.62 $\pm$ 4.68 cm and 53.87 $\pm$ 6.10 kg, respectively. Daily intakes of energy were 1597.8 $\pm$ 302.35 kcal(76.0% RDA). Iron intakes were 13.72 $\pm$ 4.17 mg (76.3% of RDA) and calcium intakes were 580.74 $\pm$ 177.21(72.5% of RDA) before iron supp]ementation. At baseline, 63% of all participants had depleted store(serum ferritin 12 ug/ml and/or transferrin saturation(TS) < 14%). After iron supplementation, this proportion declined to 19.3%. 55.6% of subjects had 12 ug/m1 of basal ferritin concentration before iron supplementation, and this proportion declined to 16.3% after iron supplementation. The basal hemoglobin(Hb) concentrations were 12.13 $\pm$ 1.01 g/dl and they increased to 12.79 $\pm$ 0.81 g/dl, which showed significant difference artier iron supplementation(p < 0.001). The basal ferritin and TS(%) were 13.24 $\pm$ 11.66 ng/ml, 18.42 $\pm$ 10.12% and they significantly increased to 32.95 $\pm$ 21.14 ng/ml, 33.53 $\pm$ 16.64%, respectively(p < 0.001). The basal total iron binding protein(TIBC) were 467.81 $\pm$ 97.24 ug/dl and they significantly decreased to 325.05 $\pm$ 48.89 ug/dl(p < 0.001) after iron supplementation. The number of tablets administered was positively correlated with serum iron(t = 0.553, p < 0.01), serum ferritin(t = 0.557, p < 0.01), TS(%)(t = 0.588, p < 0.01) and negatively correlated with TIBC(t= -0.409, p <0.01). The anemia symptoms such as ‘Shortening of breath when going upstairs(p < 0.01)’, ‘Tired out easily(p < 0.01)’, ‘Feeling blue(p < 0.001)’, ‘Decreased ability to concentrate(p < 0.01)’, and ‘Poor memory(p < 0.001)’improved significantly after iron supplementation. In this study, daily iron supplementations were efficacious in improving the iron status and anemic symptoms of female high school students. Regular check-ups and nutrition education for adolescents are necessary because of their vulnerability to iron deficiency. Further studies are needed to determine the minimum effective dose of iron and to examine the adverse effect of long-term iron supplementation.

• 한국수자원학회논문집
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• 제47권10호
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• pp.973-983
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• 2014

본 연구는 밭경지 현장실험을 통해 다양한 초생대 초종을 적용하여 밭의 비점오염저감효과 분석 및 초생대에 적용 가능한 적합한 초종을 선정하고자 하였다. 경북 군위군에 위치한 면적 $1,500m^2$, 경사 5%의 밭경지를 선정하여 시험포를 조성하였으며, 시험포내에는 대조구 1개와 초생대 처리구 6개로 구성된 총 7개의 시험구를 조성하였다. 츄파, 피, 바랭이, 잔디, 톨페스큐, 켄터키블루그라스를 포함하는 6개의 초종을 선정하여 초생대 실험을 수행하였다. 현장실험 결과 대조구 대비 초생대의 유출저감효과는 6.1~77.8%였으며, 비점오염저감효과는 TS의 경우 15.6~90.3%, T-P의 경우 49.9~96.6%, T-N의 경우 6.7~91.1%를 나타내었다. 전체 오염인자 중에 초생대로 인해 전반적으로 높은 비점오염저감 효과를 나타낸 것은 TS, T-P, T-N, SS인 반면, BOD, TOC와 $NO_3^-$는 낮은 저감효과를 보였다. 비점오염저감 및 유지관리측면에서 가장 유리한 초생대 초종은 잔디로 평가되었다. 본 연구결과를 통해 우리나라 농촌지역 밭 비점오염저감을 위한 관리기법으로 초생대가 효과적으로 활용가능하리라 사료되며, 보다 장기적이고 다각적인 현장실험을 통해 초생대 현장적용을 위한 설계 지침서 개발이 요구된다.

• 유기물자원화
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• 제12권3호
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• pp.126-133
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• 2004

본 연구는 복합형공정을 이용한 고농도 양돈폐수의 유기물 및 질소 인 제거율을 검토하기 위한 것으로 단일 SBR공정과 복합형 공정을 각각 Run I(SBR), Run II(Struvite Tank - SBR)로 명명하고 고도처리 반응기의 유무에 따른 각 Run별 처리효율을 비교하였다. 각 Run별 유기물 제거율을 살펴보면 Run I의 경우 TS 제거율은 43%, VS 제거율은 39%, SS 제거율은 88%, COD 제거율은 70%이고 Run II의 TS 제거율은 52%, VS 제거율은 52%, SS 제거율은 88%, COD 제거율은 82 %으로 struvite tank가 설치된 Run II의 유기물 제거율이 더 높았다. 또한 각 Run별 암모니아와 T-P제거효율은 Struvite Tank를 설치한 Run II의 암모니아와 T-P의 제거율이 각각 90%와 57%로, Run I의 56 %와 49%보다 효율이높았다. 특히 암모니아의 경우 Run II가 Run I 보다 매우 높은 효율을 보였으며, Struvite Tank의 설치가 질소와 인의 제거에 매우 효율적인 공정임을 알 수 있었다. 따라서 본 실험 결과 고도처리반응기(Struvite Tank)와 SBR(Sequencing Batch Reactor)을 조합한 복합형 공정이 고농도의 양돈폐수처리에 매우 적합한 공정으로 판단되어진다.

• Journal of Trauma and Injury
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• 제19권2호
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• pp.159-163
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• 2006

Purpose: The number of patients transported by the Helicopter Emergency Medical Service (HEMS) has increased recently. In our review of the Korean HEMS, there was no established helicopter utilization criteria or triage tool on the scene, so many patients with minor injuries were transported to tertiary care centers. The aim of this study is to evaluate the percentage of patients with minor injuries and to propose a more appropriate triage tool for predicting the need for transport to a tertiary care center. Methods: The subjects of this study were 59 trauma patients transported to Asan Medical Center (AMC) from the scene by Seoul HEMS from January 2004 to December 2005. The Triage score (TS), Injury Severity Score (ISS), and modified Canadian Triage and Acuity Scale (mCTAS) were calculated as severity scales. Patients with minor injuries were defined as those with TS=9, ISS${\leq}15$, and mCTAS${\geq}3$. We evaluated the association of TS, ISS, and mCTAS with the appropriateness of transport. Results: Many of the patients transported to tertiary medical centers were classified as having a minor injury: TS=9 group 35 cases (72.9%), ISS${\leq}15$ group 30 cases (62.5%) and mCTAS${\geq}3$ group 27 cases (56.2%). However, 56.2% (27/59) of the patients were appropriately transported according to need for admission or an operation. The more severely injured patients classified by TS, ISS, and mCTAS were more appropriately transported to a tertiary center (p<0.05). Conclusion: Many patients with minor injuries were transported to a tertiary center from the scene directly. The TS can be easily calculated by an emergency medical technician at the scene. Thus, we propose the TS as a useful triage tool for determining the necessity of transport to a tertiary center by helicopter.