• Title/Summary/Keyword: Tap water

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Quenching Curves for VOCs in the Analysis of Groundwater $^{14}C$ using Liquid Scintillation Counter (액체섬광계수기를 이용한 지하수의 $^{14}C$ 측정에서 휘발성유기화합물(VOC)에 대한 소광곡선)

  • Lee, Kil-Yong;Cho, Soo-Young;Yoon, Yoon-Yeol;Ko, Kyung-Seok;Kim, Yong-Je
    • Journal of Soil and Groundwater Environment
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    • v.12 no.6
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    • pp.53-59
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    • 2007
  • Optimal quenching curves have been studied for the accurate analysis of $^{14}C$ in groundwater polluted by reducing efficiency of volatile organic compounds (VOCs) in liquid scintillation counter (LSC). The quenching parameters (SQP(E)) were measured for ten VOCs such as benzene, toluene, ethylbenzene, o-(m-,p-)xylene, trichloroethylene (TCE), tetrachloroethylene(PCE), carbon tetrachloride and chloroform. The quenching curves were plotted using $^{14}C$ standard solution and chloroform as a quenching agent. Optimal plotting conditions were determined for standard solution, LSC measuring time and the concentration of chloroform. The quenching effects of chlorinated organic compounds such as TCE, PCE, carbon tetrachloride and chloroform were greater than those of BTEX (benzene, toluene, ethylbenzene and xylene). Optimum measuring time was 100 minutes far 7,000 dpm/mL standard solution. A few mL of chloroform should be added for good quenching curves. These quenching curves have good correlation coefficients (> 0.99) and the curves could be applied to accurate analysis of $^{14}C$ in groundwater and tap water.

An Investigation into the Release of Chemical Oxygen Demand in Organic Filter Media (유기성 여재로부터 화학적 산소요구량 물질의 방출에 관한 연구)

  • Guerra, Heidi B.;Kim, Youngchul
    • Journal of Wetlands Research
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    • v.22 no.3
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    • pp.171-177
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    • 2020
  • To improve the nitrogen reduction capability of stormwater treatment systems subjected to intermittent saturation, organic materials are often added as filter media. However, these materials can be an additional source of organic carbon and increase the chemical oxygen demand (COD) in the outflow. In this study, different types of organic filter media were subjected to a batch leaching test to observe and quantify the release of COD. Results reveal that the initial pH of the tap water used for soaking which is 7.5-7.7 is conducive to the release of organics from the media to the leachate. The highest amount of COD released was observed in yard clippings and woodchip followed by compost and bark mulch. The leaching of organics also increased as the size of the media decreases due to higher surface area per volume. In addition, empirical regression analysis predicted that COD from these organic media will be exhausted from the material in 3-5 months to up to 26 months depending on the type of media. The results of this study can serve as a guide in estimating the potential release of COD in organic media in order to ensure their safe application in stormwater treatment facilities.

Viability of eggs, filariform larvae and adults of Stronglyloides venezuelensis (Nematoda: Strongyloidea) maintained in vitro (베네수엘라분선충 (Strongvloides venezuelensis)의 충란, 감염자충 및 성충의 실험관 내 배양)

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    • Parasites, Hosts and Diseases
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    • v.36 no.2
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    • pp.99-108
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    • 1998
  • The present study was performed to check the viability of eggs, filariform larvae and adults of Strongvloines venezueLensis exposed to various conditions for an in vitro maintenance. The eggs in the feces remained viable for about 25 days at $4^{\circ}C$ and 15 days at room temperature. However, the isolated eggs in sterile saline lost their viability within 24 hr at $4^{\circ}C$. The eggs in morula stage were very sensitive to air drying and rapidly lost their viability (=12 hrs. Filariform larvae survived for a maximum period of 45 days in fecal suspension and 28 days in 0.12% nutrient broth in polyvinyl culture bags maintained at $20^{\circ}C$. On the other hand, those isolated from nutrient broth cultures survived for a maximum period of 32 days in tap water and 22 days in sterile saline at $20^{\circ}C$. The mature adult worms obtained from experimentally infected rats survived maximally for 9 days in serum supplemented (10% rat-serum) 0.12% nutrient broth and 4 days in serum free nutrient broth at $37^{\circ}C$ while the culture media were changed at an alternate day. The adult female worms deposited fertile eggs in serum supplemented and serum free nutrient broth cultures, however, the hatched larvae (Ll) were not able to develop to the filariform stage in the culture media and found to die within 24 hr of maintenance. The present findings on an in vitro maintenance of different stages of 5. uenezueLetis may provide useful information for biological and biochemical studies with Strongyloines species. Key words: Strongvloides venezuelensis. viability in vitro maintenance, free-living filariform larvae (L3), embryonation of eggs

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Analyses of Microbiological Contamination in Cultivation and Distrubution Stage of Tomato and Evaluation of Microbial Growth in Tomato Extract (토마토의 생산·유통단계에서 유해미생물 오염 및 추출물에서 미생물 증식)

  • Yun, Hyejeong;Park, Kyeonghun;Ryu, Kyoung-Yul;Kim, Byung Seok
    • Journal of Food Hygiene and Safety
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    • v.28 no.2
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    • pp.174-180
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    • 2013
  • This study investigated the microbiological contamination of tomato in cultivation and distribution stage. Growth of Escherichia coli O157:H7 and Listeria monocytogens examined in tomato extracts (0.1, 1.0, and 10.0%) and incubation temperatures (5, 15, 25, and $35^{\circ}C$). In cultivation stage of tomato, total aerobic bacteria were 7.77 log CFU/g in gloves of APC (Agricultural Products Processing Center) worker and Bacillus cereus were 0.33 log CFU/g at nutrient tank, respectively. And Staphylococcus aureus, Salmonella spp., were not detected. After APC stage, total aerobic bacteria were significantly higher compared with before-APC stage. Among of general, pesticide-free and organic produce in tomato were no significant difference in microbial contamination. Coliforms of tomato in small vinyl package were significantly higher when compared to tomato in whole boxes package. There was no significant difference in bacteria count between unwashed tomato and washed tomato using tap water for one minute. The growth of E. coli O157:H7 and L. monocytogens in tomato extracts were decreased significantly as the concentration increased, and the microbial population was reached the lowest point during storage in 10% tomato extracts concentration for 72h at $5^{\circ}C$. However, the population of E. coli O157:H7 and L. monocytogens were gradually increased at 7.33~8.51 and 7.73~8.60 log CFU/ml during storage at $15{\sim}35^{\circ}C$ for 72h, respectively.

Study on the Quality Characteristics of Pork By-product on the Different Pretreatment Process (돈육 부산물의 전처리 조건에 따른 품질특성 연구)

  • Kim, Tae-Kyung;Ku, Su-Kyung;Lee, Hye-Jin;Lee, Cheol-Won;Kim, Young-Boong;Jeon, Ki-Hong;Choi, Yun-Sang
    • Korean journal of food and cookery science
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    • v.32 no.6
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    • pp.716-723
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    • 2016
  • Purpose: This study was conducted to improve the quality characteristics of pork intestine through different pretreatment processes. Methods: We washed pork intestine by both physical (tap water, UV, and sonication) and chemical methods (alcohol, acetic acid, flour and NaCl) as pretreatment process. The physicochemical (pH, color, volatile basic nitrogen (VBN), and 2-thiobarbituric acid reactive substances (TBARS)) and microbial properties of pre-treated pork small intestine were evaluated. Results: The nature of the pretreatment method influenced the pH value of pork small intestine. The acetic acid treatment resulted in the lowest pH value. In physical method, the color value and the number of microorganism were significantly affected by sonication as compared to other treatments. TBARS value of pork small intestine after all the treatments was lower than the control. However, VBN exhibited no significant differences in its value irrespective of the nature of treatment. Appearance and control exhibited lowest value in response to sonication treatment. However, off-flavor and overall acceptability were higher in sonication treatment than other treatments. In chemical method involving NaCl and flour treatments, lightness and redness were lower than other treatments. Lowest VBN and TBARS values were noted in alcohol and acetic acid treatmentsand no growth of E. coli and coliform bacteria was observed. The other treatments resulted in lower values of VBN, TBARS, and microbial counts than the control. Appearance and color value after alcohol, acetic acid, and flour treatment were lower than the control and NaCl treatment. Off-flavor and overall acceptability of by-product after alcohol, flour, and NaCl treatments were higher than the control and acetic acid treatment. Conclusion: Overall, we present NaCl treatment and sonication treatment in the form of a combination pretreatment method as the optimal condition for processing pork intestine.

Screening of saline tolerant plants and development of biological monitoring technique for saline stress. II. Responses of emergence and early growth of several crop species to saline stress. (내염성 식물의 탐색 및 생물학적 염해 모니터링 기술의 개발 II.염분 스트레스에 대한 작물의 출현과 초기 생장 반응)

  • Shim, Sang-In;Lee, Sang-Gak;Kang, Byeung-Hoa
    • Korean Journal of Environmental Agriculture
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    • v.17 no.2
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    • pp.122-126
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    • 1998
  • This experiment was conducted to verify the responses of major crop species to saline stress.To determine the saline tolerance of crop species, sevral crop species were cultivated under sand-culture system using Hoagland's nutrient solution whit 200mM NaCl. The crop species showing saline tolerance were cotton(Gossypium indicum), maize(Zea mays), barely(Hordeum vulgare), and wheat(Triticum aestivum) but perilla (Perilla frutescens) and leguminous crops, mung bean(Phaseolus radiatus), azuki bean(Phaseolus angularis) and soy bean(Glycin max) showed very por tolerance. One the typical symptom was the darkening of leaf color due to increase of chlorophyll concentration.Among of the plant families, Fabaceae was the most susceptible but crop species belonging to Poaceae were more proper for cultivating on reclaimed tidal land in the course of desalinazation. It was suggrsted that the crop species belonging to Fabaceae, a sensitive family to soil salinity, must be cultivated when the soil salinity decreased below 10ds/m. To know the critical salinity level for crop growth,salinity of saline soil collected from reclaimed tidal land was adjusted from 10.0ds/m tp41.7ds/m with tap water. It was suggested that the ECs of the soil in which the plant height of each crop spicies was reduced to 50% of control plant were 22.6 and 21.7 ds/m in rice, barley, corn, mung bean, and soy bean,respectively.

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Physicochemical Analysis and Sensory Evaluation of Fermented Soy Sauce from Gorosoe(Acer mono Max.) and Kojesu(Betula costata T.) Saps (고로쇠 및 거제수나무 수액 간장의 이화학적 분석 및 관능 평가)

  • Choi, Sun-Young;Sung, Nak-Ju;Kim, Haeng-Ja
    • The Korean Journal of Food And Nutrition
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    • v.19 no.3
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    • pp.318-326
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    • 2006
  • Soy sauce was prepared with the addition of Gorosoe and Kojesu saps instead of tap water to make ordinary soy sauce, respectively. The changes of free sugar, organic acid, mineral, amino acid and nucleotides and other compounds during the fermentation of soy sauce were assessed. The free sugar were found to be fructose, glucose, galactose and sucrose in soy sauce of saps but sucrose was not detected in ordinary soy sauce. Galactose contents were dominant free sugar in all samples. The contents of butyric acid were dominant among 7 kinds of organic acid while fumaric acid was trace amount during the fermentation of soy sauce. The contents of potassium and phosphorus among 13 kinds of minerals were dominant during the fermentation of soy sauce. In the amino acid composition of soy sauce, dominant amino acid was glutamic acid(185.6${\pm}$1.0 mg/100 ml above), but proline and arginine were not detected. AMP detected above 7.5${\pm}$O.2 ${\mu}$mol/100 ml was dominant while inosine was not detected during the fermentation of soy sauce. The results of sensory evaluation in the fermented soy sauce of Gorosoe was 'liked more' than that of soy sauce of Kojesu and control.

The study on the penetration and washing features of blood on the surface of fabric (천에 혈액이 침투되는 특성 및 침투된 혈액이 세탁되는 특성 연구)

  • Kim, Yeounjeung;Lim, Jaehee;Hong, Sungwook
    • Analytical Science and Technology
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    • v.30 no.5
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    • pp.270-278
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    • 2017
  • The absorption of blood onto the surfaces of white cotton, polyester, rayon, and nylon fabrics was studied. Different categories of fabrics (woven and knitted) with diverse thickness, were manually folded twice to obtain four fabric layers, and $100{\mu}L$ of human blood was dropped onto the surface of the fabrics. The amount of blood that penetrated the fabric layer and the shape of bloodstain observed on the fabrics were influenced by the chemistry, thickness, and texture of the fabric. The blood bearing fabrics were left to dry for 3 days, washed by hand using tap water, and Lumiscene was then sprayed onto the fabrics to enhance the latent bloodstain for comparison of the shape of the bloodstain before and after washing by hand. The features of the bloodstain after washing varied greatly with the recipient fabrics. Additionally, stronger luminescence was observed at the surface where the blood was deposited compared to the background. However, it was confirmed that physical contact during the washing can deform the original shape of the bloodstain. The effect of the drying time on the bloodstain after hand washing was also studied. $100{\mu}L$ of blood was dropped on the surfaces of the fabrics and dried for 0, 1, 12, 24, 72 h, and 7 days, then washed by hand, before the bloodstain was enhanced with Lumiscene. The results of this experiment indicated that the increased drying time induces stronger chemiluminescence of Lumiscene. However, after drying of the bloodstain for 7 days, the luminescence of the bloodstain was decreased at the blood deposited site and increased around the blood deposited site.

A STUDY ON THE MARGINAL LEAKAGE OF RESTORATIONS WITH DIFFERENT CAVOSURFACE MARGINS (와연형태(窩緣形態)에 따른 와연누출(邊緣漏出)에 관(關)한 실험적(實驗的) 연구(硏究))

  • Shin, Han-Ju;Choi, Ho-Young;Min, Byung-Soon;Park, Sang-Jin
    • Restorative Dentistry and Endodontics
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    • v.12 no.1
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    • pp.119-129
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    • 1986
  • The purpose of this study was to evaluate the marginal leakage of glass ionomer cement with different cavosurface margins. 192 class V cavities were prepared on freshly extracted non-carious teeth and glass ionomer cement were inserted according to the manufacturer's instructions. Cavity preparations for this investigation were performed in four groups. The experimental specimens were made by packing the glass ionomer cement (Fuji Ionomer Type II G-C Co. Japan) into the prepared 192 cavities of four groups with different modes: Group I. - The 48 cavities with $90^{\circ}$ butt-joint cavosurface preparation and restored with glass ionomer cement. Group II. - The 48 cavities with butt-joint preparation modified by $135^{\circ}$ beveling the cavosurface in the dentin and restored with glass ionomer cement. Group III. - The 48 cavities with butt-joint preparation modified by cutting a chamfer in the dentin and restored with glass ionomer cement. Group IV. - The same 48 cavities as group I, and overfilled with glass ionomer cement beyond the cavosurface angle. And four groups above described divided into three subgroups by means of conditioning the cavity walls: Control group. - Glass ionomer cement filled in the prepared 64 cavities after being cleaned with a stream of tap water. Phosphoric acid treatment group. - Glass ionomer cement filled in the prepared 64 cavities after being conditioned with a 50% phosphoric acid. Citric acid treatment group. - Glass ionomer cement filled in the prepared 64 cavities after being conditioned with a 50% citric acid. All 192 specimens were immersed in the 2.0% basic fuchsin solution and subjected to thermal stress at one-minute intervals ($4{\pm}2^{\circ}C$ to $60{\pm}2^{\circ}C$) for 70 minutes before exposure to the dye. The specimens were sectioned ecclesiologically through the center of the restorations for different periods of immersion time, 24 hours, 7 days, 14 days 30 days. The sections were examined under a stereoscopic microscope. The results were as follows: 1. The degree of marginal leakage in group II and III was greater than that in group I and IV. 2. The degree of marginal leakage in phosphoric acid treatment group was similar with that in control group. 3. The degree of marginal leakage in citric acid treatment group was less than that in control group. 4. In all groups, the degree of marginal leakage in phosphoric acid treatment group was greater than that in citric acid treatment group. 5. There is no statistical difference of the degree of marginal leakage according to the immersion time in the dye solution.

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Side-Effects of SCB Liquid Fertilizer on Seed Germination and Physiological Activity of Pinus densiflora and Maackia amurensis Seedling (소나무와 다릅나무의 종자 발아와 유묘의 생리적 활성에 대한 SCB 액비 효과)

  • Han, Sim-Hee;Kim, Du-Hyun;Kim, Hyun-Suk;Yoo, Se-Kuel;Kim, Pan-Gi
    • Journal of Korean Society of Forest Science
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    • v.98 no.3
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    • pp.255-262
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    • 2009
  • This study was carried out to investigate the effects of SCB (Slurry Composting & Biofiltration) liquid fertilizer on seed germination properties and physiological activities of P. densiflora and M. amurensis seedling on the sand and tailing soil. Seed germination of two, tree species on the sand and tailing soil was delayed and inhibited under SCB treatment. Seedling growth of two species was also reduced by SCB application, and the growth reduction was associated with its concentration. Chlorophyll content decreased in the leaves of SCB-treated P. densiflora but increased in the leaves of SCB-treated M. amurensis when compared to control seedlings irrigated with tap water. On the other hand, Malondialdehyde (MDA) content, an indicator of lipid peroxidation, decreased in the leaves of SCB-treated P. densiflora, whereas it increased in the leaves of SCB-treated M. amurensis. Antioxidative enzyme activities in the leaves of P. densiflora increased on sand soil treated with 1/6 diluted SCB solution and on tailing soil treated with 1/3 diluted one, whereas those of M. amurensis seedlings increased only on tailing soil applied with the normal SCB solution and the 1/3 diluted SCB solution, respectively. These results were considered as side-effects of SCB liquid fertilizer which might accumulate salt through the physical changes in the soil.c