http://chineseinput.net/에서 pinyin(병음)방식으로 중국어를 변환할 수 있습니다.
변환된 중국어를 복사하여 사용하시면 됩니다.
Humic Acid Removal from Water by Iron-coated Sand: A Column Experiment
김현정(Hyon Chong Kim),Seong Jik Park,Chang Gu Lee,Yong Un Han,Jeong Ann Park,Song Bae Kim 대한환경공학회 2009 Environmental Engineering Research Vol.14 No.1
Column experiments were performed in this study to investigate humic acid adhesion to iron oxide-coated sand (ICS) under different experimental conditions including influent humic acid concentration, flow rate, solution pH, and ionic strength/composition. Breakthrough curves of humic acid were obtained by monitoring effluents, and then column capacity for humic acid adsorption (Ccap), total adsorption percent (R), and mass of humic acid adsorbed per unit mass of filter media (q(a)) were quantified from these curves. Results showed that humic acid adhesion was about seven times higher in ICS than in quartz sand at given experimental conditions. This indicates that humic acid removal can be enhanced through the surface charge modification of quartz sand with iron oxide coating. The adhesion of humic acid in ICS was influenced by influent humic acid concentration. Ccap and q(a) increased while R decreased with increasing influent humic acid concentration in ICS column. However, the influence of flow rate was not eminent in our experimental conditions. The humic acid adhesion was enhanced with increasing salt concentration of solution. Ccap, q(a) and R increased in ICS column with increasing salt concentration. On the adhesion of humic acid, the impact of CaCl₂ was greater than that of NaCl. Also, the humic acid adhesion to ICS decreased with increasing solution pH. Ccap, q(a) and R decreased with increasing solution pH. This study demonstrates that humic acid concentration, salt concentration/composition, and solution pH should be controlled carefully in order to improve the ICS column performance for humic acid removal from water.
김현정 ( Kim Hyon-chong ),박성직 ( Park Seong-jik ),이창구 ( Lee Chang-gu ),한용운 ( Han Yong-un ),김성배 ( Kim Song-bae ) 한국농공학회 2008 한국농공학회 학술대회초록집 Vol.2008 No.-
In this study, attachment of bacteria in granular activated carbon (GAC) was investigated using column experiments. Bacterial species used in the study was Enterococcus faecalis ATCC 10100. The experiments were performed with coconut-based GAC and iron-impregnated GAC under two different ionic strength conditions. In coconut-based GAC, about 77.3% of bacteria was attached in 1 mM while in 10 mM about 61.6% was attached. In iron-impregnated GAC, about 62.6% was attached in 1 mM ionic strength while about 53.3% was attached in 10 mM. Results showed that ionic strength and iron-impregnation could enhance the bacterial attachment in GAC.
칼럼실험에 의한 입상활성탄에서 Enterococcus faecalis의 부착 연구
김현정(Hyon Chong Kim),박성직(Seong Jik Park),이창구(Chang Gu Lee),한용운(Yong Un Han),김성배(Song Bae Kim) 大韓環境工學會 2009 대한환경공학회지 Vol.31 No.2
본 연구의 목적은 입상활성탄에서 이온강도와 철첨착이 Enterococcus faecalis의 부착에 미치는 영향을 분석하는 것이다. 야자계 입상활성탄(c-GAC), 철첨착된 야자계 입상활성탄(fc-GAC), 산세척된 야자계 입상활성탄(a-GAC), 그리고 철첨착된 산세척 야자계 입상활성탄(fa-GAC)에서 박테리아 부착을 관찰하기 위하여 두 가지 용액조건(NaCl 1, 10 mM)에서 칼럼실험을 수행하였다. 실험결과, c-GAC에서 이온강도가 1에서 10 mM로 증가함에 따라 박테리아의 질량회수율은 77.3에서 61.6%로 감소하였고, a-GAC에서는 질량회수율이 71.6에서 32.3%로 감소하였다. 이는 이온강도가 증가함에 따라 입상활성탄에서 박테리아의 부착이 증진될 수 있음을 나타낸다. 한편, fc-GAC에서 질량회수율은 62.6% (1 mM)과 53.3% (10 mM)이었고, fa-GAC에서는 50.8% (1 mM)과 16.9% (10 mM)이었는데, 이들 질량회수율이 c-GAC와 a-GAC에서의 질량회수율보다 낮았다. 이는 철첨착에 의하여 입상활성탄에서 박테리아의 부착이 증진될 수 있음을 나타낸다. 본 연구는 입상활성탄에서 박테리아의 부착과 관련하여 이온강도와 철수산화물 첨착의 영향에 대한 정보를 제공하고, 나아가 표면이 변형된 입상여재를 이용한 미생물의 제거에 관한 지식을 증진시킬 것이다. The aim of this study was to investigate the influence of ionic strength and iron impregnation on the attachment of Enterococcus faecalis to granular activated carbon (GAC). Column experiments were performed to examine bacterial adhesion to coconut-based GAC (c-GAC), iron-impregnated c-GAC (fc-GAC), acid-washed c-GAC (a-GAC) and iron-impregnated a-GAC (fa-GAC) under two different solution (NaCl 1, 10 mM) conditions. Results showed that bacterial mass recovery in c-GAC decreased from 77.3 to 61.6% while in a-GAC it decreased from 71.6 to 32.3% with increasing ionic strength from 1 to 10 mM. This indicates that bacterial attachment to GAC can be enhanced with increasing ionic strength. Results also showed that the mass recoveries in fc-GAC were 62.6% (1 mM) and 53.3% (10 mM) while they were 50.8% (1 mM) and 16.9%(10 mM) in fa-GAC, which were lower than those in c-GAC and a-GAC. This demonstrates that bacterial adhesion to GAC can be enhanced through iron impregnation. This study provides information regarding the effects of ionic strength and iron impregnation on bacterial attachment to GAC. Furthermore, this study will advance our knowledge of bacterial removal in surface-modified granular media.
이승현(Seung Hyun Lee),김도훈(Do Hoon Kim),이청우(Chung Woo Lee),김동원(Dong Won Kim),김현정(Hyon chong Kim),박수경(Soo Gyeong Park),설다은(Da eun Seul),박주현(Joo Hyun Park),김신혜(Shin hye Kim),최문영(Moon young Choi),정진형(Jin Hy 대한임상노인의학회 2017 대한임상노인의학회지 Vol.18 No.1
Background: Elderlies and adults might face dissimilar fates in terms of prevalence of metabolic syndrome or mortality owing to it, even if they share the same waist circumferences (WC). However, researches that might shed light on such possibility is lacking. As such, this following study aims to delve into the relationship between WC and mortality among elderlies. Methods: Subjects for the elderly cohort study were selected from NHIS-senior. Among 251,593 patients who are aged ≥65 years and qualified to having received at least one health examination between the year of 2009 and 2012, 75,856 subjects were selected. Study subjects were then divided into eight groups of set WC intervals; the study was followed up until the year of 2013 to identify total mortality of aforementioned eight groups, after which hazard ratio of each group was calculated in respect to the reference group with WC interval of 85∼90 centimeters. Results: Elderlies with WC of over 95 centimeters, whether analyzed wholly or separately as male/female, faced significant increases in mortality; on the other hand, elderlies with that of less than 95 centimeters did not. The waist interval group associated with the lowest mortality rate differed between male (80∼85 centimeters) and female elderlies (75∼80 centimeters). Conclusion: A large waist circumference is a risk factor of mortality among elderlies. Hence, strict management of a waist circumference should be reinstated to reduce mortality of elderlies.
공극 매질체에서 이온강도의 변화에 따른 박테리아의 부ㆍ탈착
이창구 ( Lee Chang-gu ),박성직 ( Park Seong-jik ),김현정 ( Kim Hyon-chong ),한용운 ( Han Yong-un ),김성배 ( Kim Song-bae ) 한국농공학회 2008 한국농공학회 학술대회초록집 Vol.2008 No.-
Column experiments were performed to investigate the influence of ionic strength on the attachment and detachment of Staphylococcus aureus to quartz sand and iron-coated sand. Experimental results showed that the mass recovery in quartz sand decreased with increasing ionic strength and bacteria detachment was occurred when ionic strength was changed. In the coated sand, however, the mass recovery remained constant even though ionic strength was changed. Also, no detachment occurred with ionic strength change.
이창구(Chang Gu Lee),박성직(Seong Jik Park),김현정(Hyon Chong Kim),한용운(Yong Un Han),박정안(Jeong Ann Park),김성배(Song Bae Kim) 大韓環境工學會 2009 대한환경공학회지 Vol.31 No.4
본 연구에서는 칼럼실험을 이용하여 석영모래와 철피복 모래에서 박테리아(Escherichia coli, Bacillus subtilis, 그리고 Staphylococcus aureus)의 부착 및 탈착에 미치는 이온강도의 영향을 조사하였다. 실험결과, 철피복 모래에서는 이온강도가 1 mM에서 100 mM로 증가함에 따라 질량회수율이 일정(E. coli=13.7±0.5%, B. subtilis=9.8±1.3%, S. aureus=13.0±2.1%)한 반면, 석영모래에서는 80.7%에서 45.3%로 감소하였다(S. aureus). 용출용액의 이온강도가 100 mM에서 0.1 mM로 감소함에 따라, 석영모래에서는 평균 39.1%의 박테리아 탈착이 일어났지만, 철피복 모래에서는 탈착이 관찰되지 않았다. 철피복 모래에서 관찰된 이러한 현상은 박테리아와 철피복 모래사이의 inner-sphere complexes(이온강도의 영향을 받지 않는)에 의한 결합 때문이다. 본 연구는 박테리아와 표면변형 다공성 여재의 상호작용에 대한 지식을 증진시킨다. This study investigated the influence of ionic strength on the adhesion and release of bacteria (Escherichia coli, Bacillus subtilis, and Staphylococcus aureus) in quartz and iron-coated sands using column experiments. Results show that the mass recovery remained constant (E. coli=13.7±0.5%, B. subtilis=9.8±1.3%, S. aureus=13.0±2.1%) in iron-coated sand while it decreased from 80.7 to 45.3% (S. aureus) in quartz sand with increasing ionic concentrations from 1 to 100 mM. As the ionic concentrations of leaching solution was lowered from 100 to 0.1 mM, average 39.1% of bacterial detachment was quantified from quartz sand, but no bacterial release was observed in iron-coated sand. The phenomenon observed in iron-coated sand can be attributed to the inner-sphere complexes between bacteria and coated sand, which have minimal effect from ionic strength. This study improves our knowledge regarding the bacterial interaction with surface-modified porous media.