• 제목/요약/키워드: Cleaning time

검색결과 624건 처리시간 0.025초

Health Effect Assessment on Cleanup Workers of an Oil Spill in Yeosu (여수 유류유출사고 방제작업자의 건강영향평가)

  • Kim, Geunbae;Kang, Tack Shin;Yoon, Mira;Jo, Hyejung;Joo, Youngkyung;Yu, Seung Do;Lee, Bo Eun
    • Journal of Environmental Health Sciences
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    • 제42권6호
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    • pp.385-395
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    • 2016
  • Objectives: The aim of this study was to assess exposure to VOCs and PAHs and the health effects on volunteers who participated in an oil spill cleanup in Yeosu. Methods: Atmospheric VOCs were evaluated in the vicinity of the accident site and questionnaire surveys were conducted to identify personal characteristics and acute health symptoms of clean-up workers seven days after the accident. The levels of metabolites of VOCs (t,t-MA, HA, PGA, MA, MHA) and PAHs (2-NAP, 1-OHP, 2-HF, 1-HPH), oxidative stress markers (TABARS, 8-OHdG) in the urine of workers were analyzed. Their correlation was determined by multiple regression analysis with SAS ver. 9.4. Results: Although the concentration of atmospheric VOCs in the residential areas were low at the time of survey, the levels of VOCs and PAHs metabolites in clean-up workers were higher than those in the control group after clean-up activities. The levels of urinary VOC and PAH metabolites were significantly increased after clean-up compared to those measured before participation. The thiobarbituric acid reactive substance (TBARS) concentrations were also increased and showed significant correlations with those of metabolites of benzene. Conclusion: This study shows that oil spill clean-up activities affect exposure to VOCs and PAHs and the health of clean-up workers. The results suggest the need for check-ups of participants in oil spill cleaning work.

Geochemical Behavior and Occurrence of Surface Oxidized Materials on the Stone Cultural Heritage: Iksan Mireuksaji Stone Pagoda (석조문화재 표면 산화물의 산출상태와 지구화학적 거동: 익산 미륵사지 석탑)

  • Lee, Dong-Sik;Lee, Chan-Hee;Yang, Hee-Jae;Choi, Ki-Young
    • Economic and Environmental Geology
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    • 제40권4호
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    • pp.375-387
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    • 2007
  • The Iksan Mireuksaji stone pagoda, designated as national treasure No. 11 in Korea, has been in the process of disassembling for reconstruction as part of the cultural heritage conservation program. The pagoda is mainly consisting of granite, which is relatively resistant to weathering. However, it has lost its original rock color due to various contaminants deposited at the surface since it exposed to the atmospheric environment long time. In this research, we categorized the secondary inorganic contaminants into the genetic type, and also quantitatively examined occurrences and types of pollutants in the oxidation area of the pagoda surface in which the area is clearly distinguished by naked eyes. Geochemical behavior of soluble pollutants through reaction experiments are demonstrated, and effective methods of cleaning for the conservation and scientific applicability of the surface cleaner are also studied.

Cutaneous Myiasis Associated with Tick Infestations in a Dog (진드기에 감염된 개의 피부 구더기증 1예)

  • Choi, Jungku;Kim, Hanjong;Na, Jiwoong;Kim, Seong-hyun;Park, Chul
    • Journal of Veterinary Clinics
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    • 제32권5호
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    • pp.473-475
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    • 2015
  • A 12-year-old intact male, Alaskan Malamute dog, which lives in the countryside, was presented with inflammation and pain around perineal areas. Thorough examination revealed maggots and punched-out round holes lesion around the perineal region. Complete blood counts (CBC) and serum biochemical examinations showed no remarkable findings except mild anemia and mild thrombocytosis. The diagnosis was easily done, based on clinical signs and maggots identification. Cleaning with chlorhexidine, povidone-iodine lavage and hair clipping away from the lesions were performed soon after presentation. SNAP 4Dx Test (IDEXX Laboratories, Westbrook, ME, USA) was performed to rule out other vector-borne diseases since the ticks were found on the clipped area and vector-borne pathogens. The test result was negative. The dog in this case was treated with ivermectin (300 mcg/kg SC) one time. Also, treatments with amoxicillin clavulanate (20 mg/kg PO, BID) was established to prevent secondary bacterial infections. Then, myiasis resolved with 2 weeks and the affected area was healed.

Effect of Media in Advanced Treatment of Sewage Using Submerged Membrane-Coupled Sequencing Batch Reactor (침지형 막결합 연속회분식 반응기를 사용한 하수의 고도처리에서 담체의 효과)

  • Kim, Seung-Geon;Lee, Ho-Won
    • Membrane Journal
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    • 제26권6호
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    • pp.470-479
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    • 2016
  • In the advanced treatment of sewage using the submerged membrane-coupled sequencing batch reactor (SMSBR) with media, the effect of media on the filtration performance and removal efficiency were investigated. Dosages of the media in the SMSBR were 10% based on working volume of reactor. As a control system, SMSBR without media and PAC, SMSBR with PAC (10 g/L) only, and SMSBR with media and PAC were also operated. The experimental results showed that there was no big difference observed in the removal efficiencies of COD, T-N, and T-P irrespective of the dosages of the media and PAC. But transmembrane pressure (TMP) of SMSBR with media increased slowly during the operation time, while that of SMSBR without media increased rapidly. Using SMSBR with media, it was possible to operate without the membrane cleaning during the 91 days. Using SMSBR with media only, after 80 days the average removal efficiencies of COD, T-N, and T-P were 95.0, 69.3%, and 51.4%, respectively.

Investigation of LC Alignment characteristic by Controlling Ion-beam Irradiation angles (이온빔 조사 각도에 따른 액정 배향 특성 연구)

  • Park, Hong-Gyu;Oh, Byeong-Yun;Kim, Young-Hwan;Kim, Byoung-Yong;Han, Jin-Woo;Chun, Ji-Yun;Han, Jeong-Min;Seo, Dae-Shik
    • Proceedings of the Korean Institute of Electrical and Electronic Material Engineers Conference
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    • 한국전기전자재료학회 2008년도 춘계학술대회 및 기술 세미나 논문집 디스플레이 광소자
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    • pp.43-43
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    • 2008
  • Recently, it is widely studied to liquid crystal (LC) alignment using ion-beam exposure. Because conventional rubbing method has some problems such as defects from dust and electrostatic charges and rubbing scratch during rubbing process. Moreover rubbing method needs cleaning process to remove these defects. Therefore rubbing-free techniques like ion-beam method are strongly required. We studied LC alignment by controlling ion-beam irradiation angles and electro-optical (EO) characteristics of twisted nematic LC on the polyimide surface. In this experiment, a good uniform alignment of the nematic liquid crystal (NLC) with the ion-beam exposure on the polyimide (PI) surface was observed. We also achieved low pretilt angle as function of ion-beam irradiation angles. X-ray photoelectron spectroscopic (XPS) analysis provided chemical evidence for LC alignment by controlling ion-beam irradiation angles. In addition, it can be achieved the good EO properties of the ion-beam-aligned twisted nematic liquid crystal display (TN-LCD) on PI surface. Some other experiments results and discussion will be included in the presentation.

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A Study on physicochemical and calcination processed characteristic of oyster shell (굴패각의 물리화학적 특성 및 소성가공 특성에 관한 연구)

  • Lee, Hak-Soo;Park, Deok-Won;Woo, Dal-Sik
    • Journal of the Korea Academia-Industrial cooperation Society
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    • 제10권12호
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    • pp.3971-3976
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    • 2009
  • In this study, we secured wasted oyster shells as raw materials in order to applicate it to corrosion preventive ceramic coating reagent in the drinking water pipeline. Then, we investigated physicochemical properties in terms of basic calcination processing. Oyster shell was composed with 92.08% of $CaCO_3$ and the shapes of the pulverized particles were mostly oval. The calcined oyster shell showed increasing tendency of weight loss and of calcium content with the lapse of time and increase of temperature. The result indicates that the higher calcination processing temperature and the uniformly smaller particle size give more efficiency during calcination process. Therefore it is anticipated to be a good ceramic material to protect a surface of cleaning bed and inside of a tap water pipes from corrosion.

Natural Dyeing of Fabrics with Guava (Psidium guajava L.) Leaf Extract II - Dyeability and Functional Property of Cotton Fabrics - (구아바 잎 추출액을 이용한 직물의 천연염색(II) - 면직물의 염색성과 기능성 -)

  • Han, Mi-Ran;Lee, Jeong-Sook
    • Fashion & Textile Research Journal
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    • 제14권2호
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    • pp.320-330
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    • 2012
  • The natural dyeing of cotton fabrics with guava leaf extract was investigated. The temperature and time of dyeing are $40^{\circ}C$ and $90^{\circ}C$ for eighty minutes, respectively. In addition, the dyebath has been set at pH 5. Sn pre-mordanted fabrics showed the highest K/S value. Regardless of dyeing temperature, K/S values were high when Al, Cu, Fe-mordanted fabrics were dyed in post-mordanting and Sn-mordanted fabrics were dyed in pre-mordanting. The K/S value of dyeing fabrics could be increased with repetitive dyeing and mordanting. Compared to untreated dyed fabrics, the K/ S values of fabrics which had been treated with soybean milk, chitosan and gall nut tannin were increased. The changed surface colors of fabrics that were treated with soybean milk, chitosan and gall nut tannin were Y, YR and achromatic colors. Fabrics dyed with alkaline water extract showed reddish color. Sn-mordanted fabrics dyed with acidic water extract showed vivid yellowish color, and Cu-mordanted fabrics dyed with ethanol extract showed yellowish green color. In case of Sn-mordanted fabrics, the washing fastness was level 4. The dry cleaning fastness also showed very excellent result with level 4-5. The rubbing fastness was better in dry rubbing than in wet rubbing of the fabrics. For the light fastness, all dyed fabrics showed low fastness. For antibacterial activity, the powder of guava leaf extract and the dyed fabrics with guava leaf extract showed 99.9% of high antibacterial activity. All dyed fabrics showed higher deodorization and UV protection rate than control fabric.

Fabric Dyeing with Myrobalan(Terminalia chebula Retz.) (미로발란을 이용한 직물염색)

  • Han, Mi-Ran;Lee, Jeong-Sook
    • Fashion & Textile Research Journal
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    • 제11권6호
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    • pp.953-960
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    • 2009
  • The natural dyeing of fabrics with myrobalan extract was investigated. After dyeing of silk, cotton and rayon with myrobalan extract, the dyeability of myrobalan extract was evaluated with the conditions of concentration, temperature, time, repeat-numbers, pH, mordants variables, the changes of dyeability and surface colors by methods of mordanting and color fastness. The wavelength of maximum absorption of the colored solution from myrobalan extract appeared at 272 nm. Therefore, the substance of myrobalan extract was verified as tannin dyes. The optimum dyeing of fabrics was carried out at 30%(o.w.f) dye concentration. Silk fabrics dyed with myrobalan extract showed the highest K/S value at the temperature of $80^{\circ}C$ when it was dyed for seventy minutes, while cotton and rayon fabrics showed the highest K/S value at the temperature of $90^{\circ}C$ when they were dyed for seventy minutes and thirty minutes, respectively. Dyeing operation was carried out in acidic dyebath of pH 3. The K/S value of silk fabric was higher in pre-mordant stage than in post-mordant, while the K/S values of cotton and rayon fabrics were higher in post-mordant stage. The surface colors of dyed fabrics were different according to used mordants: Al and Cu mordanted fabrics were dyed in yellowish colors, while Fe mordanted fabric was dyed in khaki-black color. Light-fastness of the color fastness was improved in Fe-mordant. Washing-fastness was relatively good, and dry cleaning-fastness of dyed fabrics was excellent.

A Relationship between Serum Carcinoembryonic Antigen Concentrations and Job Titles of a Shipyard Workers (조선소 근로자의 직종과 혈청 암배아성 항원 농도와의 관련성)

  • Jung, Kap Yeol;Kim, Jung Won;Ye, Byeong Jin
    • Journal of Korean Society of Occupational and Environmental Hygiene
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    • 제23권2호
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    • pp.41-49
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    • 2013
  • Objectives: The purpose of this study was to clarify the association between serum carcinoembryonic antigen (CEA) and type of work in the shipbuilding industry. Methods: 1,072 final study subjects were admitted to a general hospital from April through July 2010 for the purpose of medical examination. Data on general characteristics such as age, smoking history, alcohol history and exercise habits was gathered through structured self-administered questionnaires. Information on job factors was collected from a medical examination, by interview and through company personnel data. Serum CEA levels were measured after eight hours' fasting and were analyzed by a radioimmunoassay. Results: On univariate analysis, the mean serum CEA level was significantly higher among married (p=0.02), older age (p<0.01), longer work time (p<0.01), smokers (p<0.01), lower education (p<0.01), and indirect and direct exposure groups (p<0.01). On multiple regression analysis, serum CEA level was influenced by smoking (p=0.001), duration of work (p=0.019), and direct exposure group (p<0.001). However, among the direct exposure group, serum CEA level was not significantly different between welding, mounting, electro-device constructive work, grinding and cleaning, and painting. Conclusions: The goal of this research was to determine if there were differences between serum CEA levels according to occupational role among shipyard workers. The direct exposure group of shipyard workers had a relatively higher level of serum CEA than did the indirect exposure group and office workers, most likely due to occupational exposure.

Bleaching Treatment of Excavated Costumes and Inference of Missing Fabrics - Conservation Treatment of General Kim’s Costumes - (출토 의복의 표백과 유실된 직물의 추정 - 충장공 김덕령장군 의복(중요민속자료 111 호)의 보존처리 -)

  • Lee Mee-Sik;Hong Moom-Kyung;Bae Soon-Wha;Ahn Myung-Sook
    • Journal of the Korean Society of Clothing and Textiles
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    • 제30권7호
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    • pp.1160-1167
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    • 2006
  • The most ideal textile conservation is to block oxygen and light from historical textiles. However it is not possible because historical textiles should be examined, cleaned, restored, and exhibited to find out its historical value. Most of excavated costumes were severely stained and soiled. They are dark yellowish brown in color. To reduce the extent and intensity of the staining and to recover the original color of gray fabrics, bleaching would be required. Conservation treatment was carried out on the 8 historical costumes which belonged to General Duk-Ryung Kim(1567-1596). Two of them do not hold the fabrics. They hold only cotton wool and a little piece of fabrics. Even though these costumes underwent the conservation treatment in 1979, they were stained and needed re-treatment. This time, they were dual-bleached using hydrogen peroxide and sodiumborohydride followed by wet cleaning to reduce the soils and stains. The treatments improved the appearance of costumes. Through the analysis of the trace of fabric, carbonized fabric fragment, and fabrics remained in other garments, we concluded the missing fabrics to be ramie or cotton. It is different result from the primary report concluded to be silk.