• Title/Summary/Keyword: Organic selenium

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A study on characteristics of influent and effluent pollutants in public sewage treatment works combined with industrial wastewater and landfill leachate (공공하수처리시설에서 수질오염물질 유입 및 배출 특성 고찰 - 산업폐수 및 매립지 침출수 연계처리 시설을 중심으로 -)

  • Jeong, Dong-Hwan;Cho, Yangseok;Ahn, Kyung-Hee;Kim, Eunseok;Kim, Changsoo;Chung, Hyen-Mi
    • Journal of Korean Society of Water and Wastewater
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    • v.30 no.6
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    • pp.673-682
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    • 2016
  • In this study, we investigated influent and effluent water pollutants in 53 Public Sewage Treatment Works (PSTWs) where industrial wastewater or landfill leachate is combined four times for two years from 2014 to 2015. Also, we analyzed the characteristics of heavy metals and volatile organic carbons at influent and effluent of these PSTWs caused by sewage treatment combined with industrial wastewater or landfill leachate. As a result, six heavy metals such as barium, copper, iron, manganese, nickel and zinc, and four volatile organic carbons (VOCs) including phenols, di(2-)ethylhexyl phthalate (DEHP), formaldehyde and toluene were observed above detection limits in most of PSTWs. Also, it was revealed that six heavy metals such as hexavalent chromium, mercury, cadmium, chromium, nickel and selenium, and four VOCs including 1,1-dichloroethylene, vinyl chloride, naphthalene, and epichlorohydrin were observed more frequently according to precipitation. As a result of reviewing the monitoring data on "Water Quality Monitoring Networks" in lower watersheds of PSTWs, both heavy metals and VOCs were below detection limits, indicating that the effluent water had little influence on the watershed. Nevertheless for the better management of influent and effluent pollutants in PSTWs, it is necessary to establish the advanced management plans for water pollutants in PSTWs, which include a list of priority substances management, monitoring plans, and guidelines for industrial wastewater and landfill leachate combined in PSTWs.

Temporal and spatial variability in the nutritive value of pasture vegetation and supplement feedstuffs for domestic ruminants in Western Kenya

  • Onyango, Alice Anyango;Dickhoefer, Uta;Rufino, Mariana Cristina;Butterbach-Bahl, Klaus;Goopy, John Patrick
    • Asian-Australasian Journal of Animal Sciences
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    • v.32 no.5
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    • pp.637-647
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    • 2019
  • Objective: The study aimed at quantifying seasonal and spatial variations in availability and nutritive value of herbaceous vegetation on native pastures and supplement feedstuffs for domestic ruminants in Western Kenya. Methods: Samples of herbaceous pasture vegetation (n = 75) and local supplement feedstuffs (n = 46) for cattle, sheep, and goats were collected in 20 villages of three geographic zones (Highlands, Mid-slopes, Lowlands) in Lower Nyando, Western Kenya, over four seasons of one year. Concentrations of dry matter (DM), crude ash (CA), ether extract (EE), crude protein (CP), neutral detergent fibre (NDF), gross energy (GE), and minerals were determined. Apparent total tract organic matter digestibility (dOM) was estimated from in vitro gas production and proximate nutrient concentrations or chemical composition alone using published prediction equations. Results: Nutrient, energy, and mineral concentrations were 52 to 168 g CA, 367 to 741 g NDF, 32 to 140 g CP, 6 to 45 g EE, 14.5 to 18.8 MJ GE, 7.0 to 54.2 g potassium, 0.01 to 0.47 g sodium, 136 to 1825 mg iron, and 0.07 to 0.52 mg selenium/kg DM. The dOM was 416 to 650 g/kg organic matter but differed depending on the estimation method. Nutritive value of pasture herbage was superior to most supplement feedstuffs, but its value strongly declined in the driest season. Biomass yields and concentrations of CP and potassium in pasture herbage were highest in the Highlands amongst the three zones. Conclusion: Availability and nutritive value of pasture herbage and supplement feedstuffs greatly vary between seasons and geographical zones, suggesting need for season- and region-specific feeding strategies. Local supplement feedstuffs partly compensate for nutritional deficiencies. However, equations to accurately predict dOM and improved knowledge on nutritional characteristics of tropical ruminant feedstuffs are needed to enhance livestock production in this and similar environments.

Recent Development of Drinking Water Quality Standard and its Application (음용수질 기준과 관리방안)

  • 권숙표
    • Journal of environmental and Sanitary engineering
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    • v.7 no.2
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    • pp.83-94
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    • 1992
  • Recently water demand is increasing as the industry prospers. The increase of water demand is followed by the increase of wastewater discharge which pollutes rivers and ground water extensively. These rivers, reservoirs and ground water are sources for drinking water and their contamination affects the quality of water supply and other potable water. In Korea there are 776 water treatment plants which supply drinking water from main rivers or reservoirs. Rivers are the biggest water source for drinking water is being contaminated, the innovation of treatment process is needed. The construction and operation of water supply facilities is under the control of the Ministry of Construction and the water supply offices of cities and provinces. However, drinking water quality is under the control of the bureau of sanitation in the Ministry of Health and Social Affairs. There are 33 items in drinking water quality standards of Korea. Trihalomethanes, Selenium, Diazinone and other three of pesticides have been included lately, The Ministry of Health and Social Affairs is planning to enhance. the level of $VOC_S$(Vola-tile Organic Compounds) standard. Drinking water quality standard is the goal to protect the quality of supply water and ground water. In order to protect the source water from domestic or industrial water, technological improvement and adequate investment should be urgently made. The ultimate goal of drinking water quality is safety and health of consumers. The more stringent the standard are, the better the water quality will be. As the drinking water quality standards become more stringent this year, various and positive solutions by the authorities concerned must be prepared.

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Synthsis of $CuInSe_2$ nanoparticles and its application to the absorber layer for thin films solar cells ($CuInSe_2$ 나노 입자 합성 및 이를 이용한 광흡수층 박막 제조)

  • Kim, Kyun-Hwan;Ahn, Se-Jin;Yun, Jae-Ho;Gwak, Ji-Hye;Jo, A-Ra;Kim, Do-Jin;Yoon, Kyung-Hoon
    • 한국신재생에너지학회:학술대회논문집
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    • 2009.11a
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    • pp.396-396
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    • 2009
  • Chalcopyrite semiconductor $CuInSe_2$ nanoparticles were prepared using a low temperature colloidal route by reacting the starting materials (CuI, $InI_3$ and $Na_2Se$) in solvents. After synthesised $CuInSe_2$ nanoparticles precursors were mixed with organic binder for the viscosity of the precursor slurry to be suitable for the doctor blade method. The mixture of $CuInSe_2$ and binder was deposited onto molybdenum-coated sodalime glass substrates to form thin film. The precursor thin films were preheated on the hot plate to remove remaining solvents and binder material. After subsequent thermal processing of the thin film under a selenium ambient, $CuInSe_2$ absorber layer with grain size significantly lager than that of the nanoparticles was formed.

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Nutritional Effects on the Environmental Health (영양과 환경과의 관계)

  • 문현경
    • Journal of environmental and Sanitary engineering
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    • v.6 no.2
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    • pp.17-31
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    • 1991
  • The effects of environmental agents on health are great concern for all. It was recognized that each human has differential susceptibility to environmental effects. Susceptibility are changed by many factors includin gdevelopmpntal processes, genetic factors, nutritional stratus, preexisting disease conditions, life style and personal habits. Of all factors nutritional factors seem to be the area most modifiable. Consequently, It is an area that must be more thoroughly evaluated. In this paper, nutrient and environment interactions are reviewed briefly with published literatures. This paper deals with the influence of micronutrients(energy, protein and fat), Vitamins (vitamin 4, vitamin B-complex, vitamin C, vitamin D and vitamin I) and Minerals(calcium, iron, selenium, zinc and other minerls) on environmental effects. The role of arch nutrient was assessed in modifyine the expression of environmental pollutant toxicity with available litertures. In each nutrient section, the effect of environment was considered in following agents : heavy metals(lead, cadmium, mercury, silver and etc), inorganic agents(nitwits, sulfite, fluoride and etc), organic agents(benzene, carbon tatra-chloride, aflatoxin, auto dye, dialbrin etc), Irritant gas(ozone, carbon monooxide and etc), physical agents(X-irradiation, ultra violet, temperature and noise) and insectcides. The extent to which nutritional status modifies environmental effects 3nd its converse, how envirollments affects nutritional status is very complex. In deed, at the present time there are more than 50 chelnical/phycical agents that affect the nutrient metabolism and/or have their toxicity either directly diminished or enhanced by nutrients of those agents, small number of agents for each nutrients have sufficient evidence to warrant any reasonable degree of confidence in their hypothesized associtation. With these information at this present time it is hard to conclude that the recommended dietary allowance for each nutrient should be reconsidered.

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Synthesis of CuSbS2 and CuSbSe2 Nanocrystals by a Mechanochemical Method (기계화학적 방법에 의한 CuSbS2와 CuSbSe2 나노입자의 합성)

  • Park, Bo-In;Lee, Seung Yong;Lee, Doh-Kwon
    • Current Photovoltaic Research
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    • v.5 no.4
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    • pp.140-144
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    • 2017
  • $CuSbS_2$ (CAS) and $CuSbSe_2$ (CASe) nanocrystals (NCs), which consist of earth-abundant elements, were synthesized by a mechanochemical method. Elemental precursors such as copper, antimony, sulfur, and selenium were used without adding any organic solvents or additives. The NCs were synthesized by milling for a few hours. The sudden phase changes occurred by self-ignition and propagation, as previously observed in other mechanochemical synthetic processes. The XRD, Raman, and TEM analysis were carried out to determine the crystallinity and secondary phase of the as-synthesized CAS and CASe NCs, confirming the phase-pure synthesis of CAS and CASe. Optical properties were investigated by UV-Vis spectroscopy and it was observed that the band gap energies were about 1.1 and 1.5 eV, respectively for CAS and CASe, suggesting the potential for the use as solar cell materials. The NC colloids dispersed in anhydrous ethanol were prepared and coated on Mo substrates by a facile doctor-blade method. The investigation on the solar cell properties of the as-synthesized materials is underway.

Effects of Selenium and Vitamin E Supplementation on Meat Quality and Shelf-Life in Finishing Pigs (Selenium과 비타민 E의 급여가 비육돈의 육질 특성 및 저장성에 미치는 영향)

  • Kim H.J.;Park J.C.;Chen Y.J.;Yoo J.S.;Lee S.J.;Kim I.C.;Kim Y.H.;Jung H.J.;Park B.C.;Kim I.H.
    • Food Science of Animal Resources
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    • v.26 no.2
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    • pp.197-203
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    • 2006
  • This study was conducted to investigate the effect of seleium (Se) and vitamin E supplementation on meat quality and shelf-life in finishing pigs. A total of eighty ($Landrace{\times}Yorkshire{\times}Duroc$) pigs (74.74 initial BW) were randomly allocated into five treatments with four replications and fed for six weeks. Dietary treatments included 1) CON (basal diet), 2) ISE2 (basal diet+0.2 ppm inorganic Se+100 ppm vitamin E), 3) ISE4 (basal diet+0.4 ppm inorganic Se+100 ppm vitamin E), 4) OSE2 (basal diet+0.2 ppm organic Se+100 ppm vitamin E) and 5) OSE4 (basal diet+0.4 ppm organic Se+100 ppm vitamin E). Cooking loss was decreased in treatment of ISE4 as compared with treatment of CON (p<0.05). Crude fat (%) of OSE2 was higher than those of others (p<0.05). Redness ($a^*$- value) of M. longissimus dorsi was increased in treatment of OSE2 as compared with other treatments after 100 of storage (p<0.05). Thiobarbituric acid reactive substances (TBARS) was decreased in treatment of OSE4 compared with treatments of CON and ISE2 after 10d of storage (p<0.05). In conclusion, Se and vitamin E combination did not significantly affect cooking loss,$a^*$- value and TBARS except for cases.

Effect of Naturally Occurring Antioxidants on the Oxidative Stability of Fish Oil (천연 산화방지제가 어유의 산화안정성에 미치는 영향)

  • Han, Dae-Seok;Yi, Ock-Sook;Shin, Hyun-Kyung
    • Korean Journal of Food Science and Technology
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    • v.23 no.4
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    • pp.433-436
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    • 1991
  • Natural compounds which could improve the oxidative stability of fish oil was screened from spices, herbs and naturally occurring antioxidants. Induction period of fish oil determined from oxidation curve by Rancimat ($80^{\circ}C$) was hardly affected with the addition of water-soluble and lipid-soluble fractions of garlic, leek, sesame leave and orange peel, and of organic acids such as citric acid, EDTA and selenium. Caffeic acid, catechin, quercetin and gallic acid laurylester, however, could extend the induction periods by $2.2{\sim}3.8$ times with the addition level of 0.1%(w/w). Rosemary extract and sesamol have a marked effect in retarding oxidation of fish oil. For example, induction periods of the oil samples stabilized with 0.1 rosemary extract and 0.1 sesamol were 16.4 hr and 11.6 hr, respectively, as compared to 4.0 hr of a control. When rosemary extract was used in combination with ascorbic acid (0.02%) or 8-tocopherol (0.2%), induction period could be extended to ca. 28 hr due to the synergism.

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Studies of separation and quantitation for selenium species in food (식품중의 셀레늄 화학종의 분리 및 정량연구)

  • Jang, Hee-Young;Min, Hyungsik;Lee, Jonghae;Pak, Yong-Nam
    • Analytical Science and Technology
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    • v.26 no.3
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    • pp.182-189
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    • 2013
  • The purpose of this research is to separate and quantitate selenium species in some food samples with HPLC-ICP-MS. Cation exchange chromatography showed efficient separation only for inorganic Se species while reversed phase ion pair chromatography showed good separation for both inorganic and organic Se species. $C_8$ column ($Symmetryshield^{TM}\;RP_8$, 3.5 ${\mu}m$, $4.6{\times}150$ mm) was used with optimum condition of 5% methanol mobile phase, 0.05% of nonafluorovaleric acid ion pairing reagent. Five standard Se species of Se(IV), Se(VI), SeCys(selenocystein), SeMet(selenomethionine) and Se-M-C(seleno methyl cystein) were separated successfully under the optimum condition (mobile phase; 5% methanol, ion-pairing reagent; 0.05% nonafluorovaleric acid, flow rate; 0.9 mL $min^{-1}$). To extract Se species, microwave assisted and enzyme-assisted extraction methods were studied. In enzyme-assisted extraction method, protease I for garlic, protease I plus trypsin for pork and mackerel, and protease XIV for tuna showed the best extraction efficiency. With the optimum condition for each sample, it was found that mostly inorganic Se, SeCys and SeMet are present in the sample studied ranging from few ${\mu}g$ $g^{-1}$ to few tens of ${\mu}g$ $g^{-1}$.

Studies on Selenium-fortified Functional Hanwoo-Beef by Utilizing Spent Mushroom Composts II. Effects of Spent Composts of Se-Enriched Mushrooms as the Dietary Se Source on Selenium Deposition in the Muscular Tissue and Plasma Glutathione Peroxidase Activity in the Finishing Hanwoo Steer (버섯폐배지를 이용한 셀레늄강화 기능성 한우고기 생산에 관한 연구 II. 셀레늄강화 버섯폐배지 첨가가 한우의 근육조직 내 셀레늄 축적과 혈중 glutathione peroxidase(GSH-Px)활성에 미치는 영향)

  • Kim, Wan-Young;Lee, Kee-Jong
    • Journal of Practical Agriculture & Fisheries Research
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    • v.6 no.1
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    • pp.116-135
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    • 2004
  • This study was conducted to investigate effects of spent composts of Se-enriched mushrooms as the dietary Se source on muscular Se deposition and plasma glutathione peroxidase (GSH-Px) activity in the finishing Hanwoo steer. Twenty Hanwoo steers were used in the experiment and they were divided into four groups in a randomized complete block design with five replicates. Treatments were four levels (0.1, 0.3, 0.6 and 0.9ppm as fed basis) of dietary Se from the combination with spent composts of Se-enriched mushrooms and/or Se non-enriched mushrooms, in which each treatment was formulated with corn and corn gluten meal and so forth. Treatment diets were fed to Hanwoo steers for 90 days until the slaughter. Dry matter intakes had no significant differences among treatments and there were no significant differences for performances such as total BW gain and ADG among treatments. The Se concentration in blood was linearly increased with increasing dietary selenium levels and reached a plateau level after 8 weeks (p<0.001). Plasma GSH-Px activities had the similar trends to blood Se concentrations by showing that the increased dietary Se level significantly increased plasma GSH-Px activities of both total and Se-dependent (p<0.001). Muscle Se contents of Se-supplemented groups were linearly increased by 1.35 ~ 1.68 folds compared with the control group (0.1ppm; 0.273㎍/dry g) and especially those of the hind legs for 0.9ppm treatment showed the highest Se content as shown 0.457㎍ per dry gram (p<0.01) corresponding to approximately 70% increase of the control group. Se retention rate in the muscle of dietary Se originated from spent composts of Se-enriched mushrooms was estimated of maximum approximately 30% and dietary Se content showed the significant correlation with plasma GSH-Px activities and muscle Se contents (p<0.01). Accordingly, Se present in spent composts of Se-enriched mushroom as the dietary Se source not only had great bioavailabilities showing higher blood Se concentration and plasma GSH-Px activities, but also increased Se deposition in the muscle for Hanwoo beef cattle.