• Title/Summary/Keyword: chemical water quality

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Re-evaluation of Ammonium Data in Seawater: an Unique Short-Term Index (해수 암모늄 자료의 재평가: 독특한 단주기 수질지표 가능성)

  • JEONG, YONG HOON;YANG, JAE SAM
    • The Sea:JOURNAL OF THE KOREAN SOCIETY OF OCEANOGRAPHY
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    • v.21 no.2
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    • pp.58-66
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    • 2016
  • We have evaluated the ammonium data in seawater as a potential short-term index for marine environment through the following steps. 1. reviewing of chemical characteristics of ammonium in seawater, 2. comparative relationships of ammonium data with other water quality indices such as DO, COD, and nutrients from Typical Marine Environment(TME) and Special Marine Environment(SME). Ammonium data generally represent negative correlation with DO, while positive correlation with COD. In particular, under frequent cases of seawater conditions showing similar concentration of COD or DO, we have limited choice of explanation for such situation. However ODIN(ODIN/RDIN) or RDIN(RDIN/TDIN) ratio could provide advanced information to understand these seawater conditions. Based on these results, we suggest ammonium data as a potential short-period index for transilient marine environment, such as benthic flux of bottom sediment, hypoxia, and algal bloom. Under overcoming several handicaps, ammonium data could be an useful tool for better understand short transformation of marine environment.

Improvement in functional properties of conger eel skin gelatin by succinylation (Succinylation에 의한 붕장어껍질 젤라틴의 기능성 개선)

  • Kim, Jin-Soo
    • Applied Biological Chemistry
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    • v.39 no.4
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    • pp.282-286
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    • 1996
  • To effectively utilize fish skin gelatin as a material for quality improvement in surimi gel from fish with a red muscle, conger eel skin gelatin was modified with succinic anhydride, and funtional properties such as emulsifying activity and emulsifying stability were determined. The degree of chemical modification incresed up to 0.3 g of succinic anhydride/g of gelatin, above this adding ratio a nearly constant value was reached. The maximum amount of modification was about 90%. The emulsifying activity and emulsifying stability of gelatin gradually increased up to 89.8% of succinylation extent, little changed above of succinylation extent. The other functional properties as solubility, water holding capacity, foam expansion and foam stability were improved following succinylation with 0.3 g of succinic anhydride/g of gelatin. Amino acid composition of succinylated gelatin was similar to that of unmodified gelatin. Heavy metal contents such as cadmium, lead, copper and zinc of succinylated gelatin were lower than those of unmodified gelatin.

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Impact of quorum quenching bacteria on biofouling retardation in submerged membrane bioreactor (SMBR)

  • Pervez, Saimar;Khan, Sher Jamal;Waheed, Hira;Hashmi, Imran;Lee, Chung-Hak
    • Membrane and Water Treatment
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    • v.9 no.4
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    • pp.279-284
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    • 2018
  • Membrane biofouling is a critical operational problem that hinders the rapid commercialization of MBRs. Quorum quenching (QQ) has been investigated widely to control membrane biofouling and is accepted as a promising anti-fouling strategy. Various QQ strategies based on bacterial and enzymatic agents have been identified and applied successfully. Whereas, this study aimed to compare indigenously isolated QQ strain i.e., Enterobacter cloaca with well reported Rhodococcus sp. BH4. Both bacterial species were immobilized in polymeric beads and introduced to two different MBRs keeping the overall beads to volume ratio as 1%. Efficiencies of these strains were monitored in terms of prolonging the membrane filtration cycle of MBR, release of extra-cellular polymeric substances, membrane resistivity measurements and mineralization of signal molecules and permeate quality. Indigenous strain (Enterobacter cloaca) was added to $QQ-MBR_E$ while Rhodococcus sp. BH4 was introduced to $QQ-MBR_R$. QQ bacterial embedded beads showed enhanced filtration cycles up to 1.4 and 2.3 times for $QQ-MBR_E$ and $QQ-MBR_R$ respectively as compared to control MBR (C-MBR). Soluble EPS concentration of 52 mg/L was observed in C-MBR while significantly lower EPS concentration of 20 and 10 mg/L was witnessed in $QQ-MBR_E$ and $QQ-MBR_R$, respectively. Therefore, substantial reduction in biofouling showed the effectiveness of indigenous strain.

Environmental Pollution and Reclamation in the Abandoned Mines in Korea (국내 폐 광산 환경오염 실태 및 처리 현황)

  • Cheong Young-Wook;Min Jeong-Sik
    • 한국지구물리탐사학회:학술대회논문집
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    • 2001.09a
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    • pp.75-89
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    • 2001
  • There are 334 coal mines and about 900 metal mines abandoned. The environmental problems such as acid mine drainage from adits etc. and the subsidence has occurred in the abandoned mines. In addition, soil has been contaminated by tailings. According to analysis of mine drainages, some of them from adits in the abandoned coal and metallic mines were acidic and polluted by heavy metals. Especially, water quality of coal mine drainages were different by areas. Treatment of mine drainage by conventional chemical treatment has the drawback because the operating cost is very expensive. The treatment system used in mine drainage is the natural treatment system such as anoxic limestone drain in adits and the constructed wetland. The method of reclamation for abandoned waste rocks and tailings impoundments are mainly landfilling.

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Effects of Number of Days After Urea Foliar Spray on Mulberry Leaf Components and Silkworms (요소 엽면시비후 경과일수가 뽕잎 화학성분과 누에에 미치는 영향)

  • 이원주;김삼은
    • Journal of Sericultural and Entomological Science
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    • v.35 no.2
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    • pp.86-88
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    • 1993
  • The effect of short term duration(1, 2 and 3 days) after urea foliar spray on leaf quality was investigated by chemical analysis of leaves and silkworm rearing with leaves treated with urea in autumn. Foliar spray increased water content by 0.4~0.7% and total nitrogen by 0.19~0.51% in leaves compared to the conventional treatment. Foliar spray increased NO3-N concentration in leaf 503~1107 ppm more than the conventional treatment. NO3-N concentration in leaf decreased with days after foliar spray. Whole cocoon weight and cocoon shell weight increased by 0.02~0.14g and 0.5~3.1 cg, respectively in foliar spray than in the conventional treatment. Though foliar spray raised NO3-N concentration in leaf, leaves harvested one day after foliar spray were no harmful to silkworm.

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The Changes of Aroma in Wine Treated with Reverse Osmosis System (역삼투압 시스템으로 처리한 포도주의 향기성분 변화)

  • Lee, Seung-Ryong;Lee, Kyu-Hee;Chang, Kyu-Seob;Lee, Suk-Kun
    • Korean Journal of Food Science and Technology
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    • v.32 no.1
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    • pp.17-24
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    • 2000
  • Reverse osmosis (RO) system was applied to improve wine quality. General wine (GEN) and wines containing different sugar levels $24^{\circ}Brix$ (RO-24) and $24^{\circ}Brix$ (RO-28) by removing pure water using RO system without sugar addition on brewing method. And they were compared by wine aroma analysis. The preparing method of analysis was LLCE (liquid-liquid continuous extraction). And volatile aroma compounds of different wines were prepared for raw, and diluted materials in same proportion. The wine aromas were described by trained twelve panelists for QDA (quantitative descriptive analysis) and showed for FD (flavor dilution)-chromatogram. Consequently, overall acceptability of RO-28 showed better than that of other treatments. Aromas of RO-28 also were represented the high contents of positive aroma compounds such as ethanol and ethyl acetate, which were identified by GC-O and GC-MS.

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Effect of Conjugated Linoleic Acid Additives on Quality Characteristics of Pork Patty (Conjugated Linoleic Acid 첨가가 돈육 패티의 품질특성에 미치는 효과)

  • Joo, Seon-Tea;Lee, Jeong-Ill;Hah, Kyung-Hee;Ha, Yeong-Lae;Park, Gu-Boo
    • Korean Journal of Food Science and Technology
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    • v.32 no.1
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    • pp.62-68
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    • 2000
  • Effects of conjugated linoleic acid (CLA) on physico-chemical properties of cooked ground pork patty were investigated for 11 days at $4^{\circ}C$. Pork patties containing 0, 1, 2, and 3% CLA were cooked at $90^{\circ}C$ for 30 min. The contents of crude protein and fat did not change whereas the content of ash and water decreased as the level of CLA enhanced. Lipid oxidation as measured by thiobarbituric reactive substances of patty was inhibited by addition of CLA. CLA treatment also reduced nitrite and cholesterol content and changed fatty acid composition. Consequently, given these positive effects of CLA, it may be assumed that CLA could be used as a fat additive for value-added pork patty.

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Ionic Compositions of PM10 and Reactive Gases during Asian Dust Events in March 2007 (2007년 3월 서울 황사 사례의 PM10 이온조성과 반응성 기체 특성)

  • Park, In-Ji;Lim, Sae-Hee;Lee, Mee-Hye;Lee, Young-Jae;Kim, Jeong-Soo
    • Journal of Korean Society for Atmospheric Environment
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    • v.27 no.4
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    • pp.395-404
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    • 2011
  • Asian dust evens took place in Seoul on 27~28 March and 31 March~1 April 2007, during which the mass and chemical compositions of $PM_{10}$ were measured at urban area in Seoul, Korea. In conjunction with $PM_{10}$ compositions, the behaviors of gas precursors such as CO, $O_3$, $SO_2$, and $NO_2$ and meteorological parameters and air mass trajectories were thoroughly examined. The earlier case was a weak dust incidence which was characterized by elevated concentrations of CO, $SO_2$ and $NO_2$ as well as secondary aerosols. In contrast, the later showed the trait of the dust aerosols associated with high $PM_{10}$ mass and $Ca^{2+}$ concentrations. In general, the fractions of ionic species against mass decreased with increase in dust loading. The ratios of ${SO_4}^{2-}$ to ${NO_3}^-$ and $SO_2$ to $NO_2$ were similar in temporal variations, suggesting the concentrations of secondary aerosols were sensitive to the level of precursor gases. In this study, $Na^+$ and $Cl^-$ were also highly elevated during the heavy dust episode, which is thought to have originated from alkaline soils spreading through the northeast regions of China.

Estimating Concentrations of Pesticide Residue in Soil from Pepper Plot Using the GLEAMS Model

  • Jin, So-Hyun;Yoon, Kwang-Sik;Shim, Jae-Han;Choi, Woo-Jung;Choi, Dong-Ho;Kim, Bo-Mi;Lim, Sang-Sun;Jung, Jae-Woon;Lee, Kyoung-Sook;Hong, Su-Myeong
    • Korean Journal of Environmental Agriculture
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    • v.30 no.4
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    • pp.357-366
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    • 2011
  • BACKGROUND: Mathematical model such as GLEAMS have been developed and successfully applied to upland fields to estimate the level of pesticide residues in soil. But, the GLEAMS model rarely applied to the Korean conditions. METHODS AND RESULTS: To evaluate pesticide transport in soil residue using the GLEAMS model from pepper plot, Alachlor, Endosulfan, Cypermethrin and Fenvalerate were applied for standard and double rate. Soil sampling was conducted and decaying patterns of pesticides were investigated. Observed climate data such as temperature and irrigation amount were used for hydrology simulation. The observed pesticide residue data of 2008 were used for parameter calibration, and validation of GLEAMS model was conducted with observed data of 2009. After calibration, the $K_{oc}$ (Organic carbon distribution coefficient) and WSHFRC (Washoff fraction) parameters were identified as key parameters. The simulated concentrations of the pesticides except Fenvalerate were sensitive to $K_{oc}$ parameter. Overall, soil residue concentrations of Alachlor, Cypermethrin and Fenvalerate were fairly simulated compared to those of Endosulfan. The applicability of the GLEAMS model was also confirmed by statistical analysis. CONCLUSION(s): GLEAMS model was eligible for evaluation of pesticide soil residue for Alachlor, Cypermethrin and Fenvalerate.

Trends in the Technology and Market of Membrane Bioreactors (MBR) for Wastewater Treatment and Reuse and Development Directions (하.폐수 처리용 MBR 분리막 기술 및 산업동향과 발전방향)

  • Cho, Il Hyoung;Kim, Ji Tae
    • Membrane Journal
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    • v.23 no.1
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    • pp.24-44
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    • 2013
  • The MBR technology has evolved rapidly over the past two decades with significant gains in performance and reliability, and reductions in costs. Membrane bioreactors (MBR) technology is widely recognised as offering a key option for enhanced wastewater treatment or reuse. The objective of this paper is then to critically review the remarkable achievement on the research and commercial applications of membrane bioreactor (MBR) technology and to present current and potential MBR markets on a global scope. This brief review of the technology incorporates five key aspects : 1) evolution of MBR practice, 2) the commercial technologies of MBRs, 3) the largest MBR installations globally (e.g. > $10,000m^3/day$), 4) MBR market growth, and 5) directions for future research. Finally, the development directions of economical, environmental and technical aspects in MBRs; 1) investment costs; 2) effluent water quality; 3) membrane materials and modules; 4) MBR equipment and treatment process; 5) operating costs (higher energy & chemical consumption); and 6) sustainability such as anaerobic MBRs in the coming years were addressed.