• Title/Summary/Keyword: Water sample

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A Study on Bacterial Contamination of Rainfall (유수의 세균오염도 조사)

  • 박재용
    • Journal of Environmental Health Sciences
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    • v.2 no.1
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    • pp.21-24
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    • 1975
  • During April and May, 1973 rain water samples were collected five different times in nine selected areas of Seoul city. The pH factor and bacteria counts were measured. The following results were obtained. 1. The lowest pH was 6.18 at Moon Rae Dong and the highest was 6.30 at Jong Am Dong. This difference is not significant at the 0. 05 level. 2. The pH factor did not vary significantly with the time of sample collection. 3. Dae Bang Dong had the highest Total Plate Count of $1.9\times 10^3/ml$, Bo Moon Dong and An Kook Dong had the lowest Total Plate Count at $4.1\times 10^2/ml$. 4. The total plate count varied greatly according to the time of sample collection. This result can be used to remove are pollutants. 5. The Total plate Count is nearly inversely proportional to the length of time during which the sample is collected.

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Studies on the Quality Evaluation and Metal Content of Fermented Doenjang added Green Tea Powder in Sanitary Canned (위생 캔으로 제조한 녹차첨가 발효된장의 품질평가와 금속물질 함량에 관한 연구)

  • Heo, Yun-Haeng
    • Journal of environmental and Sanitary engineering
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    • v.22 no.1 s.63
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    • pp.37-47
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    • 2007
  • In order to improve the Quality of fermented soybean Doenjang was investigated. The samples were prepared and fermented by the koji made with A. oryzae, B. subtilis and B. natto strains, that the product added green tea powder with sanitary canned food. 1. The water content of sample was 50.30-42.14%, pH value 6.03-5.52 and total acidity, 3.01-3.87. 2. The reducing sugar content for samples was 9.35-7.81%, Amino-N, 7.96-9.21%. 3. In the sensory evaluation test, the good sensory qualify that was S-2 sample than to S-1 and S-3. 4. The heavy metals analyzed from sample cans, tin, iron and lead content were 27.31-29.04 ppm, 5.32-5.91 ppm and trace amount.

Microstructural characteristics in tough pitch copper for revealing the work hardening region

  • Okayasu, Mitsuhiro;Taki, Tatsuya;Takasu, Satoshi;Takeuchi, Shuhei;Shiraishi, Tetsuro
    • Advances in materials Research
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    • v.1 no.4
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    • pp.349-359
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    • 2012
  • To reveal localized plastic deformation zones in a tough pitch copper, the etching characteristics of a copper sample have been examined. The etching was carried out on a sample surface using an etchant consisting of 25 ml nitric acid solution and 75 ml water. To clarify the plastic deformation zone, the sample deformed plastically was heated to between $250^{\circ}C$ and $300^{\circ}C$ before the etching process. This is due to a change of the microstructure and crystal orientation in the plastic deformation zone producing recrystallized small grains. In this case, the plastically deformed zone is severely etched, whereas the undeformed zone is only slightly etched. Identification of the details of the deformation zone from the etching is further discussed.

Studies on the Quality Evaluation and Metal Content of Sanitary Canned by Fermented Soybean of Bacillus starter (위생캔으로 제조한 Bacillus Starter 발효대두의 품질 평가와 금속물질 함량에 관한 연구)

  • 허윤행
    • Journal of environmental and Sanitary engineering
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    • v.17 no.3
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    • pp.14-20
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    • 2002
  • In order to improve the quality and sensory evaluation of Fermented Soybean(Chungkugjang meju) were investigated. The samples were prepared and fermented by the inoculation of Bacillus strains (B. subtilis, number 1, B. natto, number 2) that the product made With sanitary canned food. 1. The water content of samples was 46.75~50.60%, pH 5.35~6.95 and total acidity 3.26~3.62. 2. The reducing sugar of content for sample was 9.49~10.05%, Amino-N, 67~396mg% and the activity of protease was 0.36~1.49unit/g. 3. The heavy metals analyzed from sample cans, iron, tin and lead content of sample were 5.32~5.84ppm, 27.31~29.04ppm and 0.019~0.021ppm. 4. Therefore, results that Chungkugjang-meju manufactured from B. natto starter induced better product Quality and sensory test than that of the B. subtilis strain.

Simultaneous Determination of Abamectin and Milbemectin Residues in Fruits

  • Lee, Young-Deuk;Kwon, Chan-Hyeok
    • Journal of Applied Biological Chemistry
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    • v.43 no.2
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    • pp.94-100
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    • 2000
  • An analytical method was developed to determine abamectin and milbemectin residues in apple, pear, and citrus using HPLC with ultraviolet absorption detection. Abamectin and milbemectin were extracted with methanol from apple, pear, and citrus samples. The extract was diluted with saline water and dichloromethane partition was followed to recover the compounds from the aqueous phase. Florisil column chromatography and aminopropyl solid-phase extraction were employed as cleanup methods to remove most of co-extractives from the sample extract. Reverse-phase HPLC using an octadecylsilyl column was successfully applied to separate and quantitate abamectin and milbemectin residues in sample extracts at the wavelength of 245 nm. Recoveries of abamectin and milbemectin from fortified samples ranged 80.4~90.3% and 90.9~96.8%, respectively. Relative standard deviations of the analytical method were less than 10% for both acaricides. Detection limit of the analytical method was 0.003 mg/kg sample for all the analytes. The proposed method was reproducible and sensitive enough to evaluate terminal residues of abamectin and milbemectin in apple, pear, and citrus.

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Corrosion and Adhesion of Electrophoretic Paint on AZ31 Magnesium Alloy Pretreated in Cerium Chemical Conversion Coating Solution

  • Phuong, Nguyen Van;Moon, Sungmo
    • Proceedings of the Korean Institute of Surface Engineering Conference
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    • 2015.11a
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    • pp.189-189
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    • 2015
  • In this study, the corrosion resistance and adhesion of electrophoretic paint (E-paint) were studied on AZ31 magnesium alloy pretreated in cerium chemical conversion coating solutions with the addition of various ethanol concentrations. It was found that with increasing ethanol concentration from 0 to 90 percent can decrease the formation of $Mg(OH)_2/MgO$ and increase the formation of nano-crystalline cerium oxides on the coating. Both corrosion resistance and adhesion of E-painted AZ31 increased with increasing ethanol concentration. The best E-paint sample was observed on the sample pretreatment in cerium chemical conversion coating solution with the addition of 80 percent of ethanol. This sample showed an excellent adhesion without paint detached after water immersion test for 500 h at $40^{\circ}C$, and only a few blisters observed at the near scratched sites after 1000 h salt-spray test.

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Evaluation of Offshore Seawater Qualify using Gametes and Embryos of Starfishes (Asterina pectinifera) (불가사리 알을 이용한 연안해수의 수질 평가)

  • Yu Chun Man;Lee Jong Bin;Park Jong Cheon;Joo Hyun Soo
    • Korean Journal of Environmental Biology
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    • v.22 no.3
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    • pp.376-380
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    • 2004
  • In August 2003, the water quality of offshore waters along the Incheon coast of Korea was evaluated by biological evaluation using gametes, embryos and early development systems of a starfish species (Asterina pectinifera). As the result of performing biological evaluations on seawater samples from a total thirteen sites, the formation rate of normal larva was 16-68%. At seawater sample from site 5 and 13, formation rate of normal larva averaged 16%, the most abnormal rate hindering the early embryo development of the experimental animal, while that of site 3 averaged 68%, the highest formation rate of normal larva. At seawater sample from site 2, 4, 7, 9, 10, 11, 12, formation rate of normal larva averaged 33-54%, those which damage the development of early embryos slightly. At seawater sample from site 1, 5, 6, 8, 13, formation rate of normal larva averaged 16-28%, those which damage the development of early embryos strongly.

An Experimental Study to Improve Heat Transfer of Epoxy Bond for Flooring Board Floor Adhesives (플로어링보드 바닥 접착제용 에폭시본드의 열전달 향상을 위한 실험적 연구)

  • Park, Cheul-Woo;Lee, Hyeun-Soo;Lim, Nam-Gi
    • Proceedings of the Korean Institute of Building Construction Conference
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    • 2022.04a
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    • pp.180-181
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    • 2022
  • The higher the addition rate, the less difference in kneading was found. This is because most of the cases are mixed with vinyl gloves by hand when immediately mixed in the field, so there is no problem of mixing dough according to the amount of addition. The mean increase temperature for 20 minutes was 31.6℃ for Plain, 38.1℃ for Al, 33.7℃ for Cu, and 5~7℃ for Al 20% added sample, 38.1℃ for Al 20% added sample, but 36.6℃ for Al 5% added sample. This suggests that it is possible to improve its own heat transferability by adding metal powder to epoxy adhesives.

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The Experimental Study on Antifungal effects of mixture of Sophorae Subprostratae Radix, Acoti Radix, and Hibisci Syriaci Cortex by the Three Types of Extraction on three species of the dermatophytes. (다양한 山豆根·川烏·木槿皮 혼합물 용액이 足部白癬菌에 미치는 영향)

  • Choi, Kwan-ho;Yoo, Jin-gon;Seo, Hyung-sik
    • The Journal of Korean Medicine Ophthalmology and Otolaryngology and Dermatology
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    • v.16 no.1
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    • pp.77-93
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    • 2003
  • This experimental study was performed to investigate the antifungal effects of mixture of Sophorac Subprostratae Radix, Aconti Radix, and Hibisci Syriaci Cortex by the three types of extraction in the dermatophytes such as Trichophyton rubrum, Trichophyton mentagrophytes, and Epidermophyton floccosum. The following results were obtained by using Minimum Inhibition Concentration(MIC) and Inhibition Zone. 1. MIC on Trichophyton mentagrophytes in Sample S-2, Sample S-3, and Sample-Y were 10${\mu}l$, respectively, showing the highest antifungal effect. 2. MIC on Epidermophyton floccosum in Sample S-2, Sample S-3, and Sample-Y were 10㎕ respectively, showing the highest antifungal effect. 3. MIC on Trichophyton rubrum in Sample S-3, Sample-Y were 10${\mu}l$ respectively, showing the highest antifungal effect. 4. The size of inhibition zone on Trichophyton mentagrophytes for Sample S-3 were 22.3mm in 10${\mu}l$, showing the highest antifungal effect. 5. The size of inhibition zone on Epidermophyton floccosum for Sample S-3 was 34.3mm in 10${\mu}l$, showing the highest antifungal effect. 6. The size of inhibition zone on Trichophyton rubrum for Sample-Y was 26.5mm in 10${\mu}l$, showing the highest antifungal effect. Whereas. in extractions, that of Sample S-3 was 12.5mm in 10${\mu}l$, showing the highest antifungal effect. 7. From the above results, Sample S-3 on Trichophyton mentagrophytes, Epidermophyton floccosum and Sample-Y on Trichophyton rubrum showed the highest antifungal effects. This results suggests that vinegar extraction excels other extraction method using water or ethanol to measure the antifungal effect on dermatophytes. In addition, the result shows that the extract of herbal medicines can be used to tinea pedis and if further study is performed, the use of the extract of herbal medicines will be valuable and beneficial in the clinical medicines. [NOTE] · S-S2 : 12-13w/v$\%$ Vinegar extract of mixture of Sophorae Subprostratae Radix, Aconti Radix, and Hibisci Syriaci Cortex. · S-S3 : 18-19w/v$\%$ Vinegar extract of mixture of Sophorae Subprostratae Radix, Aconti Radix, and Hibisci Syriaci Cortex. · S-Y : Miconazole nitrate

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Property of Filature Water against the Solubility of Cocoon Layer Sericin Seoul National Silk Conditioning House (제사용수의 수질이 견층 세리신(Sericin) 용해에 미치는 영향 (제2보))

  • 김병호;원성희
    • Journal of Sericultural and Entomological Science
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    • v.15 no.2
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    • pp.45-53
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    • 1973
  • 1. The sericin solubility increased rapidly as the increase of water M-alkalinity. 2. The acidity of the treated water was nutralized at the over 25ppm of M-alkalinity. 3. The more M-alkalinity of the sample water is, the more M-alkalinity was found after cocoon treat. 4. The total hardness of sample water seemed to be droped as M-alkalinity increased. 5. The sericin solubility also seemed to be droped as the increase of water acidity. 6. In case of treat finish with cocoon, the acidity and total hardness seemed to increase as the acidity of the water increased, but M-alkalinity was nutralized at 20~40 ppm of water acidity or the M-alkalinity could not be found in case over 40ppm of acidity. 7. In case increase of iron component with sample water, sericin solubility seemed to drop down, and mangan component showed the same nature but dull drop. 8. After cocoon was treated with water, acidity, M-alkalinity and total hardness were increased by the extraction from cocoon shell because of pH and treating temperature but not because of iron componnent. Mangan component, however, affected as to increase of acidity and total hardness but to decrease for M-alkalinity. 9. In case change of M-alkalinity and total hardness, sericin solubility has increased also. 10. In case constant pH and total hardness, the more M-alkalinity is, the more sericin solubility was found. 11. In case constant pH, total hardness, and M-alkalinity, the more acidity is, the less sericin solubility was found. 12. In case constant pH(6.8) and M-alkalinity, the more total hardness is, the less sericin solubility was found. 13. Though the combination of water, high solubility water, medium solubility water and low solubility water were prepared. The high solubility water desolved sericin 2.2% more than low solubility water. And the medium solubility water desolved sericin as much as 2.4~2.9%. 14. It was found that the most important factors for filature water are pH, M-alkalinity, acidity and total hardness which may need more words for optimum filature water development. 15. In case of repeat use of water, the buffer action of water has increased so that the sericin solubility to be decreased.

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