• Title/Summary/Keyword: UV dose

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Effect of Coagulants and Separation Methods on Algal Removal in Water Treatment Process (정수처리에서 응집제 종류와 분리공정이 조류 제거에 미치는 영향)

  • Park, Hung-Suck;Lee, Sang-Yoon
    • Journal of Korean Society of Environmental Engineers
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    • v.22 no.2
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    • pp.279-289
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    • 2000
  • The objective of this study was to investigate the effect of coagulants and solid-liquid separation methods on algal removal in water treatment processes. Thus characterization of raw water quality in terms of turbidity. UV-254, $KMnO_4$ consumption, chlorophyll-a and correlation analysis of these parameters were conducted. In addition, the effect of commercial Al-based coagulants(Alum. PAC and PACS) on algal removal was studied by turbidity and organic removal, algal species removal, characteristic of pH drop and alkalinity consumption using laboratory jar tests. Organic components including UV-254, $KMnO_4$ consumption, chlorophyll-a in case of algal bloom were highly correlated with turbidity and the correlation coefficients of UV-254, $KMnO_4$ consumption, chlorophyll-a with turbidity were 0.775, 0674 and 0.623, respectively. In coagulation and sedimentation, the Al-based coagulants showed similar efficiency of organic and turbidity removal in low organic($KMnO_4$ consumption below 15mg/l) and low turbidity(below 30NTU). However, PAC and PACS showed better algal removal than alum in high organic concentration($KMnO_4$ consumption above 20mg/l) and high turbidity(above 100NTU) raw water conditions generated by high algal growth, which is considered to be due to the floc settleability. In comparison of sedimentation and flotation after chemical coagulation and flocculation, the removal efficiency of organic and turbidity were higher in case of alum dose with flotation than with sedimentation, while those were better in case or PAC and PACS with sedimentation than with flotation. Thus, Alum with flotation and PAC and PACS with sedimentation is recommended for efficient algal removal. The dominant phytoplankton in raw water were Microcystic and pediastrum simplex and the removal efficiency of algae with sedimentation using alum. PAC and PACS were 27%, 45% and 22% respectively, while those with DAF showed 100% removal of phytoplankton and zooplankton.

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Guidelines and Optimum Treatment for Agriculture Reuse of Reclaimed Water (농업적 용수재이용 수질기준을 고려한 적정 하수재처리에 관한 연구)

  • Jung, Kwang-Wook;Jeon, Ji-Hong;Ham, Jong-Hwa;Yoon, Chun-Gyeong
    • Korean Journal of Ecology and Environment
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    • v.36 no.3 s.104
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    • pp.356-368
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    • 2003
  • Water quality of effluent from wastewater treatment plants (WWTPS) was reviewed to examine the feasibility of agricultural reuse using USEPA and WHO guidelines. It might meet the guidelines for BOD and SS, however, the most critical microbiological concentration was too high and further treatment is required. The pilot study of three treatments were performed to reduce microbiological concentrations. The UV irradiation was proved to be very effective in disinfection of secondary level effluent, and about 30 mW ${\cdot}$ s/$cm^2$ of dose was suggested to meet the even most stringent USEPA guidelines. Slow sand filter demonstrated effective removal of bacteria, and effluent concentration of total coliform (TC), fecal coliform (FC), and E. coli. dropped from about 10,000/100 mL to 300, 200, and 150 MPN/100 mL, respectively, showing over 95% removal. These level of bacterial concentration sufficiently meet the WHO guidelines ($10^3\;{\sim}\;10^5$ FC/100 mL), and could meet the more stringent USEPA guidelines (200 FC/100 mL) if properly applied. Slow sand filter also provided about 50% removal of SS, turbidity, and BOD in addition to bacterial removal. The removal efficiency of pond system was relatively poor, but still showed over 85% removal and effluent concentration of TC, FC, and E. coli was all below 10,000/100 mL. The pond system alone could meet the WHO guidelines, but hardly meet the USEPA guidelines and further treatment might be necessary. Overall, three methods evaluated in the study treat the effluent to meet the WHO microbiological guidelines for agricultural reuse. The UV disinfection and slow sand filter might also could the USEPA guidelines, while the pond system can hardly meet the USEPA guidelines if applied alone. The WHO and USEPA guidelines were made based on data from upland field agricultural system and may not be directly applicable to the paddy field agricultural system. Therefore, national standards for agricultural reuse of reclaimed water should be made considering domestic agricultural systems as well as international guidelines. Also, further investigation is recommended to develop optimum and feasible treatment measures for agricultural reuse of effluent from WWTPs.

Decomposition of 2,4,6-Trinitrotoluene (TNT) by Gamma Ray Irradiation (감마선 조사에 의한 2,4,6-Trinitrotoluene (TNT)의 분해)

  • Lee, Byung-Jin;Lee, Myun-Joo
    • Journal of Korean Society of Environmental Engineers
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    • v.27 no.1
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    • pp.1-10
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    • 2005
  • The purpose of this study was to evaluate the potential of a gamma irradiation to decompose 2,4,6-trinitrotoluene(TNT) in an aqueous solution. The decomposition reaction of TNT by gamma irradiation was a pseudo first-order kinetic over the applied initial concentrations($25{\sim}100mg/L$). The dose constant was strongly dependent on the initial TNT concentration. The removal of TNT was more efficient at pH below 3 and at pH above 11 than at neutral pH(pH 5-9). The required irradiation dose to remove over 99% of TNT was 40, 80 and 10 kGy, individually at pH 2, 7 and 13. The dose constant was increased by 1.6 fold and over 15.6 fold at pH 2 and 13, respectively, when compared with that at pH 7 When irradiation dose of 200 kGy was applied, the removal efficiencies of TOC were 91, 46 and 53% at pH 2, 7 and 13, respectively. Ammonia and nitrate were detected as the main nitrogen byproducts of TNT and glyoxalic acid and oxalic acid were detected as organic byproducts. The results showed that a gamma irradiation was an attractive method for the decomposition of TNT in an aqueous solution. However, regarding the application of high energy radiation for the TNT decomposition and mineralization, an application of an acidic pH below 3 to the solution before irradiation should be considered.

Antioxidative and Protective Effects of Corn Silk (Zea mays L.) Extract on Human HaCaT Keratinocyte (옥수수수염 추출물의 항산화효과 및 피부각질세포 보호효과)

  • Kim, Hyun Young;Seo, Woo Duck;Seo, Kyung Hye;Lee, Mi-Ja;Choi, Sik-Won;Lee, Kwang-Sik;Kim, Sun Lim;Kang, Hyeon Jung
    • KOREAN JOURNAL OF CROP SCIENCE
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    • v.61 no.3
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    • pp.184-190
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    • 2016
  • We investigated the antioxidative and protective effects of corn silk (Zea mays L.) ethanol extracts on human HaCaT cells and erythrocytes. The NICS-2 fraction, extracted from corn silk, exhibited favorable 1,1-diphenyl-2-picrylhydrazyl (DPPH) and 2-azino-bis-(3-ethylbenzothiazoline-6-sulphonic acid (ABTS) radical scavenging activities with $IC_{50}$valuesof$13.3{\pm}0.3{\mu}g/mL$ and $14.2{\pm}0.1{\mu}g/mL$ when compared with those of ${\alpha}$-tocopherol, a positive control, with $IC_{50}=10.4{\pm}02.2$ and $22.2{\pm}3.6{\mu}g/mL$, respectively. In addition, we investigated skin protection effects of NICS extracts of corn silk in HaCaT keratinocytes. To investigate the pharmacological potential of NICS-1 and NICS-2 extracts of corn silk on UV-B-induced damage in HaCaT cells, we measured the activity of interleukin (IL) 1a. Our results showed that all the corn silk extracts inhibited the UV-B-induced activity of IL-1a. In particular, NICS-1 extracts of corn silk significantly suppressed IL-1a activity in a dose-dependent manner without inducing cytotoxicity. These results indicate that the ethanol extracts of corn silk (Zea mays L.) could function as natural cytoprotective agents and antioxidants in biological systems, particularly the skin exposed to UV radiation, by protecting cellular membrane against reactive oxygen species (ROS).

The Development of Filter for Environmental Improvement in Land Based Seawater Fish Farm III. Purification Efficiency of Rearing Seawater by Screen Filter and Ultraviolet (필터의 개발을 통한 해수 육상수조식 양식장의 환경개선에 관한 연구 III. 스크린필터 및 자외선 등의 운행에 따른 사육수의 정화효과)

  • KANG Ju-Chan;PARK Soo-Il;KIM Seoung-Gun
    • Korean Journal of Fisheries and Aquatic Sciences
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    • v.32 no.4
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    • pp.501-506
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    • 1999
  • This study was conducted to evaluate the purification efficiency in rearing water of the land based fish farm by screen filter and ultra violet (UV) irradiation. Purification efficiency for rearing seawater has been examined with screen filter of 60 $\mu$m pore size and UV irradiation at dose of 0.5 $mWS/cm^2$ for 5 months. Purification efficiency by changing of temperature, salinity, pH, DO, total bacteria and Vibrio species in rearing seawater by filtering and UV irradiation were not significant during 5 months, However, the removing rate of suspended solid and turbidity of rearing seawater were $43.8\~45.6\%$ (average, $44,7\%$) and $29.2\~33.2\%$ (average, $31,3\%$) by filtering, respectively. Also, Purification efficiency for the $NO_3^{-}-N,\;NO_2^{-}-N,\;NH_4^{+}-N$ and $PO_4^{3-}-P$ were $21.3\~21.9\%$ (average, $21.6\%$), $24.1\~25.2\%$ (average, $24.7\%$), $17.6\~17.8\%$ (average, $17.7\%$) and $19.0\~20.4\%$ (average, $19.7\%$) respectively by the system used on this study.

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Anti-inflammatory effects of the Rubus occidentalis seed extracts on UV-B induced inflammation in HaCat cells (각질형성세포에서 UV-B와 사이토카인에 의하여 유도되는 염증 반응에 대한 복분자 씨앗 추출물의 항염증 효과)

  • Kim, Dong-Hee;Park, Tae-Soon;Son, Jun-Ho
    • Journal of Applied Biological Chemistry
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    • v.59 no.3
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    • pp.247-253
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    • 2016
  • It confirmed the applicability as an anti-inflammatory material from Rubus occidentalis seed (RSE) extract. In HaCaT cells to evaluate the anti-inflammatory potential as a material RSE extract on the activity of the inflammatory factors caused by UVB and $IFN-{\gamma}/TNF-{\alpha}$. We measured the activity of ROS, interleukin-$1{\beta}$ ($IL-1{\beta}$), interleukin-6 (IL-6) and interleukin-8 (IL-8) by ROS-Glo $H_2O_2$ assay and ELISA kit. Our results showed that the RSE extracts inhibit the UVB and $IFN-{\gamma}/TNF-{\alpha}$-induced ROS activities and expression of $IL-1{\beta}$, IL-6 and IL-8 in a dose-dependent manner. Also it was found that inflammatory mediators of the expression of cyclooxygenase-2 (COX-2) inhibition were also brought, the expression of which is increased $PGE_2$ by COX-2 also inhibited. Finally RSE extracts measure the seed expression of filaggrin in the skin barrier, the main factor of the extract could be confirmed to increase the expression of the filaggrin damaged as a result of this concentration-dependent manner. Through this, it was able to confirm that the efficacy RSE extract to protect the inflammation by restoring the damaged layers of the epidermis. Results from more than RSE extract was able to confirm that the extract that has anti-inflammatory effects by improving the inflammation being produced from UVB.

Oral Administration of KTNG0345 Prepared from Red Ginseng Extracts Reduces UVB-induced Skin Wrinkle Formation in Hairless Mice

  • Lee, Min-Jung;Won, Chong-Hyun;Lee, Se-Rah;Kim, Ji-Sook;Oh, Inn-Gyung;Hwang, Eui-Il;Kim, Na-mi;Kang, Byeong-Choel;Chung, Jin-Ho
    • Journal of Ginseng Research
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    • v.32 no.1
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    • pp.48-56
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    • 2008
  • Chronic ultraviolet (UV) exposure is the major cause of photoaging that causes skin wrinkling, roughness, dryness, laxity, and pigmentation. Recently, increasing efforts are being made to understand the relationship between foods and skin health. Ginsenosides are present in ginseng (Ginseng Radix Rubra) extract, and are known to have biomedical properties, such as, anti-oxidant and anti-inflammatory effects. In this study, we investigated whether KTNG0345 prepared from red ginseng extracts delivered orally reduces skin wrinkling and ultraviolet B (UVB)-induced wrinkle formation in hairless mouse skin. KTNG0345 was administrated orally to the mice (5 times a week) during the period of UVB-irradiation (3 times a week) for 8 weeks at three different doses of 300 mg/kg, 500 mg/kg and 1000 mg/kg (w/v). UV doses were increased weekly by 1 MED (1MED = 75 $mJ/cm^2)$ up to 4 MED and then maintained at this level. After the 8-week administration period, it was found that orally administered KTNG0345 significantly inhibited UVB-induced wrinkle formation in a dose-dependent manner. Increases in skin thickness caused by UVB were prevented by KTNG0345. Moreover, it also significantly inhibited matrix metalloproteinases (MMP) -13 and MMP-9 expressional inductions by UVB. In addition, KTNG0345 was observed to prevent UVB-induced water loss of epidermis in hairless mouse skin. Our results demonstrate that orally administered KTNG0345 has anti-wrinkling effects in hairless mouse skin, and suggest that dietary red ginseng and herbal mixture may be considered a functional beauty food for preventing UVB-induced skin wrinkles.

Induction of Two Types of Gynogenetic Diploid of Sweet Fish, Plecoglossus altivelis and Verification by Isozyme Marker (은어 2종류의 자성발생 2배체의 유도와 Isozyme 유전자에 의한 배수성의 확인)

  • 손진기
    • Development and Reproduction
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    • v.4 no.1
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    • pp.79-85
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    • 2000
  • This study was made to optimize the conditions needed to produce two types of gynogenetic diploids in the sweet fish, Plecoglossus altivelis. Firstly, ultraviolet (UV) ray doses between 3,000 erg to 14,000 erg/$\textrm{mm}^2$ were tested to inactivate sperm genetically. Based on the appearance of the haploid syndromes in the embryo, a dose of UV ray 6000~7000 erg was required to inactivate sperm genetically. Then, cold shock treatment at 1~2$^{\circ}C$ for 15~30 min were conducted to retain the 2nd polar body in inseminated egg. The best elapsed time before the start of the cold shock was examined between 5~8 min. The experiments in which began 5 min after insemination at 1~2$^{\circ}C$ during 17.5 min gave 21.2% survival rate and 89.7% normal eyed embryo rate. The gynogenetic diploid produced by suppression of the first cleavage, a considerably high number of heteroploids appeared and high mortality was observed at the metamorphosis stage, so further investigation is needed. The production of gynogenetic diploids were confirmed by GPI isozyme marker. The heterozygous type in Gpi-1 locus was observed in the meiotic-G2N as a result of gene-centromere recombination during meiosis. The heterozygous type was never observed in mitotic-G2N and showed segregation into two homozygous types at Gpi-1 locus.

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Removal of Natural Organic Matter using Potassium ferrate(VI) (Potassium ferrate(VI)를 이용한 자연유기물질 제거)

  • Lim, Mi-Hee;Kim, Myoung-Jin
    • Journal of Korean Society of Environmental Engineers
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    • v.29 no.12
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    • pp.1337-1344
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    • 2007
  • In this research, we synthesized potassium ferrate(VI) acting as an oxidant, disinfectant, and coagulant, and used it to treat natural organic matter(NOM, HA and FA) in river water. The removal efficiencies obtained by $UV_{254}$ ranged from 20.7 to 73.6% for 10 mg/L HA and from 52.6 to 77.5% for 10 mg/L FA in Nakdong river sample as the ferrate dose varied from 2 to 46 mg/L(as Fe). However, the removal efficiencies by TOC analysis ranged from 0 to 20.3% for HA and from 0 to 26.6% for FA at the same ferrate doses. The removal efficiencies of NOM increased either with decreasing pH or with increasing temperature. The removal efficiency of HA by ferrate was comparable to those by traditional coagulants such as $Al_2(SO_4)_3{\cdot}18H_2O$, $FeSO_4{\cdot}7H_2O$, and FeO(OH). The reaction between ferrate and HA reached a steady state within 60 seconds, showing first-order with respect to the reaction time. The removal efficiencies of HA by traditional coagulants were improved by pretreatment of HA using a small amount of ferrate.

Protective Effect of Water Extract of Lycii Cordex Radicis on Lipid Peroxidation of Rat Skin Exposed to Ultraviolet B Radiation (자외선 B에 노출된 쥐 표피의 지질과산화에 대한 지골피 물 추출물의 보호효과)

  • Gwak, Jun-Su;Ryu, Seung-Hee;Moon, Gap-Soon;Choi, Dong-Seong;Park, Sung-Hye;Han, Jong-Hyun;Ahn, Byung-Yong
    • Applied Biological Chemistry
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    • v.45 no.4
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    • pp.218-222
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    • 2002
  • Lycii Cordex Radicis extract (gigolpi) examined through SOS Chromotest showed a strong, dose-dependent antimutagenic effect on the tert-butyl hydroperoxide (t-BOOH) induced mutagenecity. Gigolpi revealed considerable superoxide anion radical scavenging activity under L-ascorbic $acid-CuSO_4$ system, but showed lower hydroxyl radical scavenging activity in photochemical test system. Hot-water gigolpi extract delayed protein oxidation, whereas lipid peroxidation of rat skin exposed to UVB radiation was inhibited. The results indicate that gigolpi possessing antioxidant activity against UVB-induced lipid peroxidation could be used as a raw ingredient for manufacturing functional cosmetics