• Title, Summary, Keyword: Surface enrichment

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Distribution of Organic Matter and Trace Metals in Surface Sediments and Ecological Risk Assessment in the Tongyeong Coast (통영연안 표층퇴적물에서의 유기물과 미량금속 분포 특성 및 생태위해성 평가)

  • YANG, WON HO;LEE, HYO JIN;KIM, GI BEUM
    • The Sea
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    • v.21 no.4
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    • pp.125-133
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    • 2016
  • We investigated the distribution of organic matter and trace metals in surface sediment from Tonyeong coast. To determine the status of trace metal pollution, we also conducted an ecological risk assessment. Relatively high concentration of TN (total nitrogen), TOC (total organic carbon), and AVS (acid volatile sulfide) was found in surface sediment located in the narrow channel (site 35-38). Spatial distribution of Cd, Cr, Ni, Co, Hg, and Zn in surface sediment was similar and high Cu concentrations were found in narrow channel. The assessment of heavy metal pollution was derived using the Enrichment factors (EF). The enrichment factor indicated that Cd was no enrichment (EF<1), Pb, Cr, Ni, Co, Zn, and Hg were minor enrichment (1

Control of Enzymatic Degradability of Biodegradable Polylactide by Blending with Non-degradable Polymers (비 분해성고분자와 블렌드를 이용한 생분해성 폴리유산의 효소분해속도 조절)

  • Jang, Seong-Ho;Park, Sang-Bo;Lee, Won-Ki
    • Journal of Environmental Science International
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    • v.19 no.9
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    • pp.1161-1167
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    • 2010
  • The effects of addition of non degradable polymers, polystyrene (PS) and poly(methyl methacrylate) (PMMA) on the rate of enzymatic degradation of biodegradable poly(l-lactide) (PLLA) have been studied in term of surface structure. Since a component in multicomponent polymeric system has shown surface enrichment, PS and PMMA which have lower surface energy than PLLA were selected as a minor blend component (5 wt%). Enzymatic degradation was carried out at $37^{\circ}C$ and pH 8.5 in the aqueous solution of Proteinase K. Two blend systems, partially miscible (PS/PLLA) and immiscible (PMMA/PLLA), showed the surface enrichment of 4 and 2 times of PS and PMMA, respectively. From the weight loss profile data, the slow degradation rate of both blend films was observed. This indicates that PS or PMMA domains which exist at surface act as a retardant of enzymatic attack.

Depth Profiles of Heavy Metals in the Surface Sediments of Haedong Reservoir

  • Byung-Chul Moon;Kwa
    • Journal of Environmental Science International
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    • v.1 no.1
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    • pp.1.2-9
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    • 1992
  • We investigated the depth profiles of heavy metals in the surface sediments at Haedong reservoir in Pusan. Sampling was done at the intervals of 50 m of drift along the water channel into the reservoir. All samples were analyzed with an ICP-AES. We determined the content of Zn, Pb, Cd, Mn, Cu, Cr, and Fe. The overall mean content of these heavy metals were observed to $(2.9{\pm}1.2){\times}10^{-3}$, $(1.3{\pm}0.7){\times}10^{-3}$, $(1.9{\pm}2.1){\times}10^{-4}$ $(2.3{\pm}1.1){\times}10^{-2}$ $(1.6{\pm}1.0){\times}10{-3}$, and $(4.5{\pm}2.6){\times}10^{-4}$ ppm/ppm Fe, recpectively excluding iron data. Mean contents of Cu show an increasing trend toward the surface of sediments, while those of U show a decreasing trend, and those of Pb and Cr are relatively stable. Comparing with the contents of heavy metals in soils at two sites of Kumjeong mountain, enrichment factors of heavy metals in the surface sediments were determined. Among heavy metals we investigated, copper showed the largest value of enrichment factor. Considering the maximum content of heavy metals in the surface sediment, the values of enrichment factors of Cu, Cd and Cr were significant which were n, 8.1 and 4.0, respectively. In leaching experiment, it appeared that Pb, Cd, Cr, and Fe in sediments were hardly leached out into water. We also examined the effect of pH on the content of heavy metals.

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Estimation of Pollution Degree of Surface Sediment from Incheon H Wharf (인천 H항 표층 퇴적물의 오염도 평가)

  • Kim, Jeong-Ho;Nam, Se-Yong
    • Journal of the Korean Society of Marine Environment & Safety
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    • v.20 no.5
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    • pp.504-510
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    • 2014
  • In this study, physico-chemical properties and pollution degree of surface sediments collected at 5 stations(S1~S5) of Incheon H wharf in March 2014 were investigated. From particle size, surface area, XRD and XRF analyses, the sediment samples consisted of similar oxides and minerals. Considering total score of COD, AVS and IL, pollution level ranged between 2 and 3 based on domestic standards. In case of heavy metal contamination, Cd, Ni and Pb were classified as moderately polluted by USEPA standards. However, Cu, Zn and Cr were classified as heavily polluted. With geoaccumulation index value($I_{geo}$), Cd contamination was estimated as class 3. In addition, the calculated enrichment factors of Cd, Pb and Zn were exceeded a value of 1. Site S4 was high as 3.1 in total enrichment factor.

Hydrophilic Modification of PET by Using Block Copolymer -Molecular Structure and Hydrophilicity of PET-PEG Block Copolymers- (블록 공중합체를 이용한 PET의 친수화 연구 - PET-PEG 블록공중합체의 구조에 따른 친수성의 비교 -)

  • 우상원;조창기
    • Textile Science and Engineering
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    • v.36 no.3
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    • pp.211-218
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    • 1999
  • Multi-block copolymers of poly(ethylene terephthalate) (PET) and poly(ethylene glycol) (PEG) were synthesized. Similarly, triblock copolymers of PET and poly(ethylene glycol) methyl ether (MPEG) were synthesized. PEG and MPEG of various molecular weights were used. Obtained block copolymers were made into film, and conditioned at 65% RH at $25^{\circ}C$ after vacuum drying. Water contact angle measurement indicated the enrichment of PET domain on the film surface after vacuum drying, and the enrichment of PEG domain on the film surface after conditioning. The hydrophilicity of the film increased as the molecular weight of PEG block increased. Also, the surface energy increased as the molecular weight of PEG increased, and this increase was mainly due to the increase in the polar component of surface energy. In spite of lower PEG contents, triblock copolymers showed relatively good hydrophilicity.

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Recovery and Survival of Listeria monocytogenes in Surface and Sea Water (지표수 및 해수로부터 Listeria monocytogenes의 분리 및 생존성)

  • Yang, Ju;Kim, Toh-Gyong;Kang, Ho-Jo
    • Korean Journal of Veterinary Research
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    • v.42 no.3
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    • pp.327-333
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    • 2002
  • The study was carried out to examine the distribution and survival rate of Listeria monocytogenes (L monocytogenes) from various source of waters using improved isolation method. In comparision of enrichment media for isolation of L monocytogenes from water, the isolation rate and 50% detection limit of the pathogen were higher in UVM modified Listeria enrichment broth (UVM) than Listeria enrichment broth (LEB). On the other hand, when compared the selective media for isolation of the pathogen from water, the isolation rate was highest in culture at Oxford agar followed by Fraser agar, and LEB agar. In order to improve enrichment method, 100 ml of water samples with 0.1 CFU/ml of L monocytogenes was inoculated into 10 ml of UVM concentrated at 10-fold, and incubated for 24 h at $36^{\circ}C$. Isolated frequency of the pathogens in improved enrichment method completely corresponded with common (filter) method. Of a total mumber of 147 water samples from river, lake and sea, the pathogen was isolated from 1 of 39 (2.6%) river water samples and 1 of 75 (1.3%) sea water samples, but no pathogen was isolated from 33 lake water samples. Serotypes of 2 isolates were identified as type 1. L monocytogenes decreased in number from 7.2-7.4 to 4.2-4.7 log CFU/ml for 1 week poststorage (5 and $20^{\circ}C$), but the pathogens were able to be detected in river and sea water until 8 weeks after storage. However, in tap water, L monocytogenes were decreased to undetectable level after 2 weeks of storage.

Organic Enrichment and Pollution in Surface Sediments from Shellfish Farming in Yeoja Bay and Gangjin Bay, Korea (패류양식어장 밀집해역의 퇴적환경내 유기물 분포특성 -여자만과 남해 강진만-)

  • Choi, Minkyu;Kim, Hyung Chul;Hwang, Dong-Woon;Lee, In-Seok;Kim, Young-Sook;Kim, Ye-Jung;Choi, Hee-Gu
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.46 no.4
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    • pp.424-436
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    • 2013
  • Organic enrichment was investigated in surface sediments from the Yeoja and Gangjin Bays of Korea, which contain dense shellfish farms, in order to evaluate the contamination status and temporal changes in shellfish farming along these coasts. The degree of organic enrichment was determined using geochemical indicators (chemical oxygen demand, ignition loss, acid volatile sulfide, total organic carbon in sediments, and total nitrogen in sediments, ammonium and nitrate in pore water, and bioluminescence inhabitation for sediments). Temporal changes in organic enrichment conditions were detected by comparing our 2012 data to those previously reported from a survey conducted in 1999/2000. Organic enrichment was significantly higher in September than in May and July, in Gangjin Bay than in Yeoja Bay, and significantly higher in shellfish farms than in reference sites not used to culture shellfish. Ammonium concentrations in pore water were two orders of magnitude greater than nitrate concentrations, suggesting that these bays represent nitrogen-reducing environments.

Depth Profiles of Heavy Metals in the Surface Sediments of $H^{o}edong$ Reservoir

  • Moon Byung-Chul;Park Kwang-Jae;Jung Eui-Han;Jeong Gi Ho
    • Environmental Sciences Bulletin of The Korean Environmental Sciences Society
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    • v.1 no.1
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    • pp.1-9
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    • 1997
  • We investigated the depth profiles of heavy metals in the surface sediments at Heedong reservoir in Pusan. Sampling was done at the intervals of 50 m of drift along the water channel into the reservoir. All samples were analyzed with an ICP-AES. We determined the content of Zn, Pb, Cd, Mn, Cu, Cr, and Fe. The overall mean content of these heavy metals were observed to $(2.9\pm1.2){\times}10^{-3},\;(1.3\pm0.7){\times}10^{-3},$ $(1.9\pm2.1){\times}10^{-4},$ $(2.3\pm1.1){\times}10^{-2},\;(1.6\pm1.0){\times}10^{-3},\;and\;(4.5\pm2.6){\times}10^{-4}$ ppm/ppmFe, respectively excluding iron data. Mean contents of Cu show an increasing trend toward the surface of sediments, while those of Cd show a decreasing trend, and those of Pb and Cr are relatively stable. Comparing with the contents of heavy metals in soils at two sites of Kumjeong mountain, enrichment factors of heavy metals in the surface sediments were determined. Among heavy metals we investigated, copper showed the largest value of enrichment factor. Considering the maximum content of heavy metals in the surface sediment, the values of enrichment factors of Cu, Cd and Cr were significant, which were 22, 8.1 and 4.0, respectively. In leaching experiment, it appeared that Pb, Cd, Cr, and Fe in sediments were hardly leached out into water, We also examined the effect of pH on the content of heavy metals.

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Factors Affecting Foam Separation of Proteins (단백질의 기포분리에 영향을 미치는 요소들에 관한 연구)

  • Lee, Boo-Young;Lee, Cherl-Ho
    • Korean Journal of Food Science and Technology
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    • v.19 no.3
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    • pp.220-224
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    • 1987
  • The concentration ranges forming surface excess of bovine serum albumin(BSA) and ovalbumin solutions were determined, and the factors affecting the foam separation of BSA were investigated. The surface tension of BSA solution decreased from 72 to 61 dynelcm, when the concentration changed from $5{\times}10^{-3}$ to $3{\times}10^{-2}%$, and the critical micelle concentration was appeared to be at 0.03% of BSA. At the isoelectric point (pH 4.9) of BSA, the foamate volume was maximum, but enrichment ratio was minimum, resulting in the maximum recovery rate. When the pH deviated from the isoelectric point, the foamate volume decreased and the enrichment ratio increased. The enrichment ratio increased, while the foamate volume decreased drastically as the temperature was elevated above $20^{\circ}C$, resulting in the decrease in recovery rate. As the gas flow rate increased, the enrichment ratio decreased and the foamate volume increased. When $(NH_4)_2SO_4$ was added, the enrichment ratio decreased, but the maximum foamate was obtained at ionic strength 7. The concentration to form the surface excess of ovlbumin, which has lower surface hydrophobicity than BSA, was 200 times higher than that of BSA. This fact indicates the possibility of selective foam separation by hydrophobicity difference of proteins.

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Chemical Characteristics for Hydrothermal Alteration of Surface Sediments from Submarine Volcanoes of the Tonga Arc (통가열도 해저화산 표층 퇴적물 내 열수변질의 화학적 특성)

  • Um, In Kwon;Chun, Jong-Hwa;Choi, Hunsoo;Choi, Man Sik
    • Journal of the Mineralogical Society of Korea
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    • v.26 no.4
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    • pp.245-262
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    • 2013
  • We analyzed 29 surface sediment samples in five submarine volcanoes (TA12, TA19, TA22, TA25, and TA26) located in the southern part of the Tonga arc for trace elements and rare earth elements to investigate characteristics of the hydrothermal alteration of surface sediments. Based on analytical results of trace element and rare earth element (REE), surface sediments of TA12, TA19, and TA22 submarine volcanoes, which are located in the northern part of the study area, were very little or not influenced by hydrothermal fluids. In contrast, some stations of TA25 and TA26 submarine volcanoes were strongly affected by hydrothermal fluids. However, these two submarine volcanoes showed different features in element concentration in the sediments. Some stations of TA25 submarine volcano showed enrichment of Ni, Cu, Sn, Zn, Pb, Cr, Cd, Sb, W, Ba, Ta, Rb, Sr, and As, however, those of TA26 submarine volcano showed enrichment of Sn, Zn, Pb, Cd, Sb, Ba, Rb, and Sr. Stations which enriched trace elements were observed, enriched REEs were also observed. Average upper continental crust (UCC)-normalized REE patterns of the surface sediments generally showed low light REE (LREE) abundances and increased heavy REE (HREE) abundances. Eu enrichment was identified at several stations of TA25 and TA26 submarine volcanoes. In addition, enrichment of Ce was found at some stations of TA26 submarine volcano and these enrichment patterns were similar with hydrothermal fluid of near stations. Furthermore, TA25 and TA26 submarine volcanoes showed different enrichment characteristics of trace elements and REE. Trace elements were concentrated at TA25 submarine volcano. TA26 submarine volcano, on the other hand, observed highly enrichment of REE especially, Eu and Ce. As a result of the investigation, the characteristics and concentrations of REEs and trace elements in the surface sediments of each submarine volcano can be applied to identify hydrothermal alteration of sediments during exploration for hydrothermal deposits.