• Title/Summary/Keyword: 사이중심도

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Studies on Controlling Mixed Annual and Perennial Weeds in Paddy Fields - On the Herbicidal Properties of Perfluidone - (수종(數種) 다년생잡초혼생답(多年生雜草混生沓)에 있어서 제초제(除草劑)에 의한 효과적(效果的)인 잡초방제(雜草防除) - Perfluidone의 작용특성구명(作用特性究明)을 중심(中心)으로 -)

  • Ryang, H.S.;Han, S.S.
    • Korean Journal of Weed Science
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    • v.3 no.1
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    • pp.75-99
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    • 1983
  • The herbicidal properties of perfluidone [1,1,1-trifluoro-N-2-methyl-4-(phenylsulponyl) phenyl methanesulfonamide] were investigated in pots and paddy fields. At the rate of 2.0kg prod./10a, perfluidone did not cause any injury to the 4 leaf stage (LS) rice seedlings. Although the crop injury increased with increasing the application rate, the injury caused by 16kg prod. perfluidone/10a gave rise to only 30% yield reduction. The crop injury was greatest when perfluidone was applied 2 days before transplanting and decreased as the application time delayed. Perfluidone showed greater crop injury to the 3 LS seedlings, at more than 7cm water depth, and at high temperature than to the 4 LS seedlings, at 3-5cm water depth, and at low temperature. Indica and indica ${\times}$ japonica rice varieties were generally more sensitive to perfluidone than japonica rice variety. Perfluidone effectively controlled most of annual weeds and such perennial weeds as Sagittaria pygmaea MIQ., Potamogeton distinctus A. BENN, Cyperus serotinus ROTTB, Scirpus maritimus L., Eleocharis kuroguwai OHWL, and Scirpus hotarui OHWL, whereas Sagittaria trifolia L. and Polygonum hydropiper SPACH. were tolerent to perfluidone. The weeding effect decreased with increasing the leaching amount of water and the overflowing of irrigated water within 24 hours after the herbicide application. When the application time was done later than 8 days after transplanting, the perennial weeds were shown at deeper soil layers, and the standing water was deeper than 7cm, the effect tended to decrease. However, there was no difference in the weeding effect between soil types. Downward movement of perfluidone in flooded soil ranged from 2 to 8cm deep. The movement increased with increasing the leaching amount of water and the application rate and at a sandy loam soil which possessed less adsorptive capacity. Residual effect of perfluidone was found at 35 to 80 days after application, which varied such factors as Soil types. Increase in the leaching amount of water resulted in decrease in the period of the residual effect. The period was shorter at non-sterilized soil than at sterilized soil. The 0.75kg ai perfluidone + 1.5kg ai SL-49 (1,3-dimethyl-6-(2,4-dichlor-benzoyl)-5-phenacyloxy-pyrazole)/ha and 1.5kg ai perfluidone + 1.05kg ai bifenox (2,4-dichlorophenyl-3-methoxy carbonyl-4-nitro phenyl ether)/ha showed less crop injury than 1.5kg ai/ha perfluidone alone. However, the weeding effect of the former was similar to that of the later.

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The Changes of Brain Injury Markers(S100-$\beta$, Neuron-Specific enolase) After Retrograde Cerebral Perfusion Under Total Circulatory Arrest in Pigs (돼지에서 역행성 뇌관류 시행 후 혈청 및 소변의 뇌손상 관련지표(S100-$\beta$, Neuron-specific enolase)의 변화)

  • 김상윤;김만호;김경환
    • Journal of Chest Surgery
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    • v.35 no.12
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    • pp.847-853
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    • 2002
  • We previously published the data that proved the safety of retrograde cerebral perfusion for 120 minutes. At this time, we planned to check the neuron-specific enolase and S100-$\beta$ in serum and urine to assess the possibility of early detection of cerebral injury. Material and Method: We used pigs(Landrace species) weighing 35 kg and performed RCP for 120 minutes. After the weaning of cardiopulmonary bypass, we observed the pigs for another 120 minutes. Systemic arterial pressure, central venous pressure, and serum and urine levels of neuron-specific enolose (NSE) and S100$\beta$ protein were checked. Central venous pressure during RCP was maintained in the range of 20 to 25 mmHg. Result: Serum levels of NSE(ng/$m\ell$) were 0.67$\pm$0.18(induction of anesthesia), 0.53$\pm$0.47(soon after CPB), 0.44$\pm$0.27(20min alter CPB), 0.24$\pm$0.09(RCP 20min), 0.37$\pm$0.35(RCP 40min), 0.33$\pm$0.21 (RCP 60min), 0.37$\pm$0.22(RCP 80min), 0.41$\pm$0.23(RCP 100 min), 0.48$\pm$0.26(RCP 120min), 0.42$\pm$0.29(30min after rewarming), 0.35 $\pm$0.32(60min after rewarming, 0.42$\pm$0.37(CPBoff 30min), 0.47$\pm$0.34(CPBOff 60min), 0.47$\pm$0.28(CPBOff 90min), and 0.57$\pm$0.29(CPBOff 120min). There was no statistically significant difference in levels between before and after RCP(ANOVA, p>0.05). Urine levels of NSE also showed no statistically significant difference in levels between before and after RCP. There was no correlation between urine and serum levels of NSE(Pearson correlation, p>0.05). Serum levels of S100$\beta$ protein(ng/$m\ell$) during the same time frames were 0.14$\pm$0.08, 0.15$\pm$0.07, 0.22$\pm$0.15, 0.23$\pm$0.07, 0.28$\pm$0.10, 0.40$\pm$0.05, 0.47$\pm$0.03, 0.49$\pm$0.12, 0.43$\pm$0.11, 0.46$\pm$0.15, 0.62$\pm$0.17, 0.77$\pm$0.21, 0.78$\pm$0.23, 0.77$\pm$0.23, and 0.82$\pm$0.33. There was statistically significant difference in levels between before and after RCP(ANOVA, p<0.05). Urine levels of NSE also showed statistically significant difference in levels between before and after RCP(ANOVA, p<0.05). There was significant correlation between urine and serum levels of NSE(Pearson correlation, p<0.05). Conclusion: The author observed the increase in serum and urine levels of S100$\beta$ after 120 minutes of RCP. Significant correlation between serum and urine levels was observed. The results were considered to be the fundamental data that could correlate this study with human-based study.

A Comparative Analysis of the Clinical and Pathological features of IgA Nephropathy and Thin Glomerular Basement Membrane Disease (IgA 신병증과 비박형 기저막 신증의 임상 및 병리학적 비교 분석 - 사구체 기저막의 비박화를 중심으로 -)

  • Chi, Geun-Ha;Ha, Chang-Woo;Kim, Young-Ju;Yoon, Hye-Kyung;Chung, Woo-Yeong
    • Childhood Kidney Diseases
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    • v.5 no.2
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    • pp.147-155
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    • 2001
  • Purpose : IgA nephropathy(IgAN) and thin glomerular basement membrane disease(TGBMD) are common glomerular diseases that cause hematuria in childhood. IgAN has characteristics of IgA deposit as the sole or predominantly localized to the mesangium Recently, it has been reported that thinning of glomerular basement membrane(GBM) is commonly accompanied with precipitation of electron dense deposits in IgAN. We performed this study to examine the frequency of thinning of GBM among children with IgAN and to analysis tile correlation between urinary abnormalities and GBM thickness and furthermore to conduct comparative analysis of the clinical and pathological features of IgAN and TGBMD. Methods : This study summarizes data collected from Department of Pediatrics, Busan Paik Hospital, Inje Medical College. Data include 51 cases who were diagnosed as IgAN from 1995 to 2000, and 26 cases who were diagnosed as TGBMD from 1990 to 2000 by percutaneous renal biopsy. Results : Males accounted for 29/51($56.9\%$) patients with IgAN and 8/26($30.8\%$) of those with TGBMD. The clinical and laboratory features between IgAN and TGBMD were significantly different regarding the incidence of proteinuria(IgAN vs TGBMD: $43.1\%\;vs\;3.8\%$, p=0.001), the incidence of co-appearance of proteinuria with hematuria ($41.2\%\;vs\;3.8\%$, p=0.001), total amount of protein in 24 hours collected urine ($808{\pm}\;mg\;vs\;251{\pm}200.7\;mg$, p=0.001) and the incidence of proteinuria more than 1 gm in 24 hours collected urine ($23.5\%\;vs\;3.8\%$, p=0.01). On the contrary, there were no significant differences in the levels of serum albumin, creatinine, BUN, and Ccr between two groups. The mean thickness of GBM in patients with IgAN was $293.0{\pm}79.2\;nm$(139.7-461.9 nm) and $180.9{\pm}35.8\;nm$(110.5-229.5 nm) in patients with TGBMD. The mean GBM thickness revealed significantly thinner in TGBMD compared than those with IgAN (P=0.0001). The frequency of thickness being less than 250 nm was $37.4{\pm}34.4\%$ in IgAN and $93.0{\pm}7.0\%$ in TGBMD (P=0.0001). But there were no correlations between urinary abnormalities and GBM thickness in patients with IgAN. Conclusion : The thinning of GBM would be one of the common pathological findings in IgAN Moreover, there is no significant correlations between urinary abnormalities and GBM thickness in patients with IgAN, However, patients with IgAN tend to have significantly higher possibilities of proteinuria, co-appearance of proteinuria with hematuria and higher total amount of protein in 24 hours collected urine compared those with TGBMD. These differences might be play all important role as progressive prognostic indicators in patients with IgAN. (J Korean Soc Pediatr Nephrol 2001;5 : 136-46)

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The Influence of the Preoperative Chronic Cyanosis on the Cardiac Troponin I in the Pediatric Cardiac Operation (지속적인 청색증에 노출된 선천성 심장병에서 수술 후 Cardiac Troponin I의 농도 변화)

  • Song, Jinyoung;Lee, Sungkyu;Lee, Jaeyoung;Kim, Soojin;Shim, Wooseup
    • Clinical and Experimental Pediatrics
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    • v.45 no.4
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    • pp.498-504
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    • 2002
  • Purpose : The purpose of this study was to evaluate the perioperative myocardial damage in pediatric congenital heart disease with the cardiac specific protein of cardiac troponin I(cTpn-I). Methods : All 25 pediatric patients who were diagnosed with tetralogy of Fallot or double outlet right ventricle were classified as group A(acyanotic, $SaO_2$ >90%), group B(mildly cyanotic, $SaO_2$ >80-90%) and group C(moderately cyanotic, $SaO_2$ <80%). The control group D was consisted of 10 patients with ventricular septal defects who were operated in the same period. We measured preoperative hemoglobin, preoperative and postoperative(24 and 72 hour) arterial oxygen saturation, cTpn-I and creatine kinase(CK-MB). Results : Total 25 patients were subdivided into 6 of group A, 12 of group B and 7 of group C. The concentrations of preoperative cTpn-I were $0.23{\pm}0.12ng/mL$ in group A, $0.25{\pm}00.12 ng/mL$ in group B, $0.26{\pm}0.13ng/mL$ in group C. And the concentrations of cTpn-I in postoperative 24 hour were $10.04{\pm}5.28ng/mL$ in group A, $12.50{\pm}6.86ng/mL$ in group B, $12.55{\pm}9.90ng/mL$ in group C. Which revealed cTpn-I in group C was higher than that of the another less cyanotic groups. In addition, the concentration of cTpn-I of group C in postoperative 72 hour was higher than any other groups. The concentration of cTpn-I in postoperative 72 hour was statistically correlated with that in postoperative 24 hour and preoperative arterial oxygen saturation(P=0.001). Conclusion : Preoperative chronic cyanosis can influence on the postoperative concentration of cTpn-I in pediatric cardiac patients, which means impairment on the postoperative myocardial recovery.

Analysis of Perception of School Foodservice Facilities and Utilities in Gyeongnam Area by School Nutrition Teachers (Dietitians) -Comparison of School Foodservice Facilities and Improvement of Utilities in Schools- (경남지역 영양(교)사의 급식시설 설비에 대한 인지도 분석 -학교급식시설 현대화 사업 완료 학교와 미완료 학교의 비교를 중심으로-)

  • Jeon, Young;Kim, Hyun-Ah
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.43 no.9
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    • pp.1447-1456
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    • 2014
  • The purpose of this study was to compare perception of school foodservice facilities and utilities in dietitians and school nutrition teachers in the Gyeongnam area between schools that improved foodservice facilities and utilities versus those who did not. From July 23 to Aug 31, 2012, 391 questionnaires were distributed, and 289 questionnaires were obtained. A total of 275 questionnaires were used for the final analysis, excluding improper ones. The results of this study were as follows. First, among 275 schools, 90 schools (32.7%) improved school foodservice facilities and utilities while 175 schools (67.3%) did not. Second, schools with improved facilities had a more well-equipped receiving room (P<0.01), preparation room (P<0.001), dishwashing room (P<0.001), storage room for supplies (P<0.001), rest-room for school foodservice employees (P<0.05), locker room (P<0.01), shower room (P<0.001), laundry room (P<0.001), boiler room (P<0.05), and room for serving cart (P<0.05) than schools with no improvement. Third, total perception score of school foodservice facilities area from schools with improved facilities (1.71) was significantly higher than that (1.60) of school without improvement (P<0.001). Fourth, total satisfaction (3.32) of school foodservice facilities and utilities in school with improved facilities was significantly higher than that (2.62) of schools without improvement (P<0.01). Fifth, schools with improved facilities had a better equipped of floor (P<0.05), entrance (P<0.001), drain (P<0.001), water supply (P<0.01), lighting (P<0.001), hand washing (P<0.001), foodservice management room (P<0.001), locker room (P<0.001), rest-room and shower room (P<0.001), and preparation room (P<0.001) than schools without improvement. However, there was no significant difference in terms of walls and ceilings, windows, ventilation, and storage. In conclusion, school foodservice facilities and utilities improvement should conducted as soon as possible.

Effect of the Angle of Ventricular Septal Wall on Left Anterior Oblique View in Multi-Gated Cardiac Blood Pool Scan (게이트 심장 혈액풀 스캔에서 심실중격 각도에 따른 좌전사위상 변화에 대한 연구)

  • You, Yeon Wook;Lee, Chung Wun;Seo, Yeong Deok;Choi, Ho Yong;Kim, Yun Cheol;Kim, Yong Geun;Won, Woo Jae;Bang, Ji-In;Lee, Soo Jin;Kim, Tae-Sung
    • The Korean Journal of Nuclear Medicine Technology
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    • v.20 no.1
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    • pp.13-19
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    • 2016
  • Purpose In order to calculate the left ventricular ejection fraction (LVEF) accurately, it is important to acquire the best septal view of left ventricle in the multi-gated cardiac blood pool scan (GBP). This study aims to acquire the best septal view by measuring angle of ventricular septal wall (${\theta}$) using enhanced CT scan and compare with conventional method using left anterior oblique (LAO) 45 view. Materials and Methods From March to July in 2015, we analyzed the 253 patients who underwent both enhanced chest CT and GBP scan in the department of nuclear medicine at National Cancer Center. Angle (${\theta}$) between ventricular septum and imaginary midline was measured in transverse image of enhanced chest CT scan, and the patients whose difference between the angle of ${\theta}$ and 45 degree was more than 10 degrees were included. GBP scan was acquired using both LAO 45 and LAO ${\theta}$ views, and LVEFs measured by automated and manual region of interest (Auto-ROI and Manual-ROI) modes respectively were analyzed. Results $Mean{\pm}SD$ of ${\theta}$ on total 253 patients was $37.0{\pm}8.5^{\circ}$. Among them, the patients whose difference between 45 and ${\theta}$ degrees were more than ${\pm}10$ degrees were 88 patients ($29.3{\pm}6.1^{\circ}$). In Auto-ROI mode, there was statistically significant difference between LAO 45 and LAO ${\theta}$ (LVEF $45=62.0{\pm}6.6%$ vs. LVEF ${\theta}=64.0{\pm}5.6%$; P = 0.001). In Manual-ROI mode, there was also statistically significant difference between LAO 45 and LAO ${\theta}$ (LVEF $45=66.7{\pm}7.2%$ vs. LVEF ${\theta}=69.0{\pm}6.4%$; P < 0.001). Intraclass correlation coefficients of both methods were more than 95%. In case of comparison between Auto-ROI and Manual ROI of each LAO 45 and LAO ${\theta}$, there was no significant difference statistically. Conclusion We could measure the angle of ventricular septal wall accurately by using transverse image of enhanced chest CT and applied to LAO acquisition in the GBP scan. It might be the alternative method to acquire the best septal view of LAO effectively. We could notify significant difference between conventional LAO 45 and LAO ${\theta}$ view.

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A Refined Method for Quantification of Myocardial Blood Flow using N-13 Ammonia and Dynamic PET (N-13 암모니아와 양전자방출단층촬영 동적영상을 이용하여 심근혈류량을 정량화하는 새로운 방법 개발에 관한 연구)

  • Kim, Joon-Young;Lee, Kyung-Han;Kim, Sang-Eun;Choe, Yearn-Seong;Ju, Hee-Kyung;Kim, Yong-Jin;Kim, Byung-Tae;Choi, Yong
    • The Korean Journal of Nuclear Medicine
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    • v.31 no.1
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    • pp.73-82
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    • 1997
  • Regional myocardial blood flow (rMBF) can be noninvasively quantified using N-13 ammonia and dynamic positron emission tomography (PET). The quantitative accuracy of the rMBF values, however, is affected by the distortion of myocardial PET images caused by finite PET image resolution and cardiac motion. Although different methods have been developed to correct the distortion typically classified as partial volume effect and spillover, the methods are too complex to employ in a routine clinical environment. We have developed a refined method incorporating a geometric model of the volume representation of a region-of-interest (ROI) into the two-compartment N-13 ammonia model. In the refined model, partial volume effect and spillover are conveniently corrected by an additional parameter in the mathematical model. To examine the accuracy of this approach, studies were performed in 9 coronary artery disease patients. Dynamic transaxial images (16 frames) were acquired with a GE $Advance^{TM}$ PET scanner simultaneous with intravenous injection of 20 mCi N-13 ammonia. rMBF was examined at rest and during pharmacologically (dipyridamole) induced coronary hyperemia. Three sectorial myocardium (septum, anterior wall and lateral wall) and blood pool time-activity curves were generated using dynamic images from manually drawn ROIs. The accuracy of rMBF values estimated by the refined method was examined by comparing to the values estimated using the conventional two-compartment model without partial volume effect correction rMBF values obtained by the refined method linearly correlated with rMBF values obtained by the conventional method (108 myocardial segments, correlation coefficient (r)=0.88). Additionally, underestimated rMBF values by the conventional method due to partial volume effect were corrected by theoretically predicted amount in the refined method (slope(m)=1.57). Spillover fraction estimated by the two methods agreed well (r=1.00, m=0.98). In conclusion, accurate rMBF values can be efficiently quantified by the refined method incorporating myocardium geometric information into the two-compartment model using N-13 ammonia and PET.

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A Study on Dietary Behavior of Chinese Consumers Segmented by Dietary Lifestyle (중국 현지 소비자들의 식생활 라이프스타일 세분화에 따른 식행동 연구)

  • Oh, Ji Eun;Yoon, Hei-Ryeo
    • Journal of the Korean Society of Food Culture
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    • v.32 no.5
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    • pp.383-393
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    • 2017
  • This study was conducted to analyze the dietary lifestyle of local Chinese consumers and to classify dietary characteristics according to their dietary lifestyle factors and dietary behaviors. This investigation was conducted for 1 month from 1 January 2017 targeting 300 adult males and females living in China using the online survey company surveymonkey. Four factors relating to dietary lifestyle were identified, gourmet factor, healthy factor, convenience factor and economic factor, and these were grouped into 4 clusters according to their dietary lifestyle factor scores. Group 1, the gourmet economy group, showed a high percentage of living alone and a high frequency of eating out, but a relatively low percentage of three regular meals per day. Their dietary lifestyle was sensitive to gourmet factors and economic factors, but less sensitive to health and convenience factors. Group 2, the wide interest group, contained a high percentage of individuals in their 30s, as well as more highly educated individuals and a higher income than other groups. Because their dietary lifestyle scores tended to be higher than those of other groups, they sought a variety of new foods and gourmet meals for enjoyment of dining and life, as well as well-being food materials and foods related to health. Group 3, the health economic group, constituted a family-type consumer group with lower income level than the other groups. Members of this group were seeking health food and natural food in their dietary lifestyle and tended to pursue a high economic profit ratio when purchasing food. Finally, group 4 showed a relatively higher percentage of women over 30 and individuals with a college level or higher education than the other groups. This group was more interested in health and taste than price and convenience, and showed the highest LOHAS orientation among middle aged Chinese women. Moreover, members of this group directly utilized their knowledge regarding nutrition in real life.

Genetic Environments of the High-purity Limestone in the Upper Zone of the Daegi Formation at the Jeongseon-Samcheok Area (정선-삼척 일대 대기층 상부 고품위 석회석의 생성환경)

  • Kim, Chang Seong;Choi, Seon-Gyu;Kim, Gyu-Bo;Kang, Jeonggeuk;Kim, Kyeong Bae;Kim, Hagsoo;Lee, Jeongsang;Ryu, In-Chang
    • Economic and Environmental Geology
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    • v.50 no.4
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    • pp.287-302
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    • 2017
  • The carbonate rocks of the Daegi Formation are composed of the limestone at the upper and lower zones, and the dolomite at the middle zone, in which the upper zone has higher CaO content than others. The colors of carbonate rock in the Daegi Formation can be divided into five types; white, light brown, light gray, gray, and dark gray. The white to light gray colored rocks correspond to the high purity limestone with 53.15 ~ 55.64 wt. % CaO, and the light brown colored rocks contain 20.71 ~ 21.67 wt. % MgO. The bleaching of carbonate rocks are not related to CaO composition of the rocks, as light gray rocks tend to be higher in CaO content than those of the white rocks at the lower zone. The pelitic components are also occasionally increased in white limestone than light grey one. $Al_2O_3$ is one of the most difficult content to remove during hydrothermal processes, so the interpretation that the limestone is purified together with hydrothemral bleaching, has little merit. The wide range (over 16 ‰) of ${\delta}^{18}O_{SMOW}$, smaller variation (within 2 ‰) of ${\delta}^{13}C_{PDB}$ are apparent in both the upper and lower zones, which indicate the Daegi Formation had been affected overall by hydrothermal fluids. The K-Ar isotopic age of hydrothermal alteration in the GMI limestone mine is $85.1{\pm}1.7Ma$. Gradual change from grey through light grey to white limestone is accompaned by lower oxygen stable isotope values, which is major evidence that the hydrothermal effect is the main process of the bleaching. Although the Daegi Formation has suffered from hydrothermal activity and increase in whiteness, there is no clear evidence demonstrating the relationship between bleaching and high purity of limestone. The purification of limestone has nothing to do with the hydrothermal activity in this area. Instead, it should be considered that the change of sedimentary environment related to see-level fluctuation which can prevent deposition of pelitic components especially $Al_2O_3$ contrbuted to the formation of the high purity limestone in the upper zone of the Daegi Formation. Considering the evidences such as increase in CaO content of limestone by depth, gradual change from calcite to dolomite at the lower zones, and occurring the high purity limestone at the upper zone, the interpretation of sequence stratigraphic aspect to the formation of the high purity Daegi limestone appears to be more suitable than that of hydrothermal alteration origin.

Characteristics of Spatio-temporal Variation of the Water Quality in the Lower Keum River (금강 하류역에서 수질의 시공간적 변화특성)

  • YANG Han-Soeb;KIM Seong-Soo
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.23 no.3
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    • pp.225-237
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    • 1990
  • Various chemical constituents were measured from April to August 1988 at the down-ward 20 stations of Keum River, which is located in the Midwest of Korea, to understand the characteristics of water quality with respect to spatio-temporal variations of each constituent. The 24-hrs continuous measurements with 2-hrs interval were made simultaneously at station 2 near the estuary weir and station 9(Ganggyeong) of 35 km upstream from the weir in April. By the results observed for one day in April at station 2, salinity has a range of $7.88\~22.14\%_{\circ}$ and its temporal variability is identical to the pattern of tidal cycle in the neigh-bouring Kunsan Harbor. However, turbidity shows relatively high values only at an interval of 4~5 hours after the lowest salinity time, though hourly fluctuation of pH is very small. Silicate and dissolved inorganic nitrogen have inversively linear correlationships with salinity, implying the concentration of the two nutrients strongly regulated by estuarine mixing of sea and river waters. In contrast, phosphate sustains roughly a constant level over a wide salinity range and distinctly lower values than those corresponding to nitrate in the oceans. Such distributions of phosphate have been observed in some estuaries, and interpreted as driven by removal of dissolved phosphate into bottom sediments and the bufforing of phosphate by particulate matter. COD values at station 2 are relatively high in day-time(particularly afternoon) and in high-salinity periods. At station 9, saltwater intrusion was never found but water level changed to the extent of 2.5 m for one day. Although each parameter at this station exhibits very slight variations in their abundance for 24 hours compared with station 2, the contents of COD, silicate and ammonia are significantly higher than at station 2. Concentration of suspended matter is relatively high in the brackish water region up to $\~20$ km above the river mouth, probably due to strong tidal stirring of the bottom de-posits. Also, relatively high pH, COD and $O_2$ saturation at the upward stations of $40\~50$ km from the weir are presumably attributable to active photosynthesis of plants in the region. In general, COD and nutrients except phosphate are higher values at the upper stations than in the estuary zone, and show the highest abundances in July nearly at all stations. Finally, in the estuarine region tidal mixing of sea-river waters seems to be an important factor controlling the distributions of turbidity, COD, silicate and nitrate as well as salinity. However, water quality in the upward fresh-water zone is remarkably variable according to months or seasons.

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