• 제목/요약/키워드: water wash

검색결과 217건 처리시간 0.02초

순환골재 세척수를 혼입한 고로슬래그 콘크리트의 압축강도 특성에 관한 실험적 연구 (An Experimental Study on the Compressive Strength Property of Concrete with Ground granulated Blast Furnace Slag Using Wash Water from Recycled Aggregates)

  • 정상경;신상엽;김영수
    • 한국건축시공학회:학술대회논문집
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    • 한국건축시공학회 2015년도 춘계 학술논문 발표대회
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    • pp.34-35
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    • 2015
  • The purpose of this study is to investigate the compressive strength property of concrete with Ground granulated blast furnace slag(GBFS) using wash water from recycled aggregate. When GBFS is reacted with water, it doesn't happen to hydraulic reaction but GBFS becomes latent hydraulic property in alkaline environment. For this reason, if it is possible to use wash water from recycled coarse aggregate as mixture water, GBFS have the advantage of early strength due to effect of activation. We investigated the compressive strength properties of GBFS concrete using wash water from recycled aggregate. According to the experimentation result, ICP-OES showed wash water from recycled coarse aggregate has a high alkali value of pH of 12. Also, compressive strength in early age using wash water can be improved as an activation.

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정수장 급속여과지 역세척 수위변화와 시간에 따른 세척 효율 평가 (Evaluation of a Rapid Sand Filter with Surface Wash and Backwash Conditions)

  • 정용준;민경석
    • 한국물환경학회지
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    • 제20권6호
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    • pp.652-656
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    • 2004
  • Both surface wash and backwash are considered as one of the most important methods that can improve the filtration efficiency in the existing water treatment plant. This study has mainly focused on the improvement of filtering efficiency by controlling surface wash and backwash time, and water level before backwash (when drained up to the trough, when drained up to 10 cm above filter bed, and when drained below 10 cm filter bed). Filtration efficiency was shown a little bit of differences depending on the operating conditions like surface wash injection pressure, the distance control between filter bed and the facility, and the types of surface wash. When the water level before backwash was reached up to 10 cm below filter bed after draining, however, the filtration velocity and the turbidity removal efficiency in the filter bed was improved. When the surface wash followed by backwash is longer, it showed a similar result. Because the proper adjustment of surface washing time makes filtration efficiency higher, therefore, it is necessary to set up the backwash time moderately.

유성오구의 부착과 제거에 있어서 폴리에스테르 직물의 표면특성 변화 (I) -발수발유 가공포의 반복세척 효과- (Changes of Surface Characteristics of Polyester Fabrics on the Deposition and the Removal of Oily Soils (I) - The Effect of Wash Cycles on the Water- and Oil-repellent Finished Fabrics in Detergency -)

  • 이정숙;하희정
    • 한국염색가공학회지
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    • 제11권6호
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    • pp.24-35
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    • 1999
  • This study was carried out to investigate the changes of surface characteristics of polyester fabrics on the deposition and the removal of oily soils from polyester fabrics in detergency, The relations between the removal of soil and the changes of surface properties of polyester fabrics treated with water- and oil-repellent agents were discussed before and after various wash cycles. Two kinds of fluoropolymers were selected as water-and oil-repellent finishing agents. The effects of water- and oil-repellent finishes were determined by the water repellency and oil repellency. The surface properties of untreated and treated polyester fabrics were evaluated with respect to contact angle and wicking time. The treatment of polyester fabrics with fluoropolymers improved efficiently water repellency, oil repellency, contact angle and wicking time. But those properties were greatly decreased after 3 times of wash cycles in detergency The deposition of oily soils on the untreated fabrics was drastically increased with increasing of wash cycles. The deposition and the removal of oily soils from fabrics treated with fluoropolymer having hydrophobic components were very low after various wash cycles. The deposition and the removal of oily soils on the fabrics treated with fluoropolymer having hydrophilic components were high comparatively after various wash cycles. Even though the surface properties of treated fabrics were greatly decreased with the increasing of wash cycles, the remains of oily soils on the fabrics were lower than those of untreated fabrics in various wash cycles. But the remains of soils were drastically increased after 10 times of wash cycles in any cases.

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Burden of Disease Attributable to Inadequate Drinking Water, Sanitation, and Hygiene in Korea

  • Kim, Jong-Hun;Cheong, Hae-Kwan;Jeon, Byoung-Hak
    • Journal of Korean Medical Science
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    • 제33권46호
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    • pp.288.1-288.12
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    • 2018
  • Background: Diarrheal and intestinal infectious disease caused by inadequate drinking water, sanitation, and hygiene (WASH) is not only a great concern in developing countries but also a problem in low-income populations and rural areas in developed countries. In this study, we assessed the exposure to inadequate WASH in Korea and estimated the burden of disease attributable to inadequate WASH. Methods: We used observational data on water supply, drinking water, sewage treatment rate, and hand washing to assess inadequate WASH conditions in Korea, and estimated the level of exposure in the entire population. The disease burden was estimated by applying the cause of death data from death registry and the morbidity data from the national health insurance to the population attributable fraction (PAF) for the disease caused by inappropriate WASH. Results: In 2013, 1.4% of the population were exposed to inadequate drinking water, and 1.0% were living in areas where sewerage was not connected. The frequency of handwashing with soap after contact with excreta was 23.5%. The PAF due to inadequate WASH as a cluster of risk factors was 0.353 (95% confidence interval [CI], 0.275-0.417), among which over 90% were attributable to hand hygiene factors that were significantly worse than those in American and European high-income countries. Conclusion: The level of hand hygiene in Korea has yet to be improved to the extent that it shows a significant difference compared to other high-income countries. Therefore, improving the current situation in Korea requires a continuous hand washing campaign and a program aimed at all people. In addition, continuous policy intervention for improvement of sewage treatment facilities in rural areas is required, and water quality control monitoring should be continuously carried out.

굴 세척액을 이용한 인스턴트 분말 수프의 제조 및 특성 (Preparation of Instant Powdered Soup Using Oyster Wash Water and Its Characteristics)

  • 김진수;허민수
    • 한국식품과학회지
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    • 제33권5호
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    • pp.534-539
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    • 2001
  • 굴통조림 가공부산물인 세척수를 효율적으로 이용하기 위하여 굴세척액을 이용한 인스턴트 분말수프의 제조를 시도하였다. 대조구인 굴 열수추출물 분말 수프는 열수추출물 분말에 식염, 분말크림, 유대체 분말, 밀가루, 대두분말, 전분, 글루코스, 양파가루의 일정량씩을 각각 혼합하여 제조하였다. 굴세척액 분말수프는 열수추출물 분말 대신에 세척액 분말을 첨가하고, 기타 첨가물의 경우 굴 열수추출물 분말 수프와 같은 비율로 첨가하여 제조하였다. 굴통조림 가공부산물 유래 분말 수프인 세척수 분말 수프는 탄수화물이 71.1%로 거의 대부분을 차지하였고, 다음으로 조단백질(10.8%), 조회분(8.1%) 및 조지방(3.5%)의 순이었으며, 대조구인 열수추출물 분말 수프와 차이가 없었다. 굴세척액 분말 수프는 휘발성염기질소, 생균수, 대장균군 및 수분활성이 각각 29.4 mg/100g, $4.6{\times}10^4\;CFU/g$, <18 MPN/100 g 및 0.246으로 위생적으로 안전한 인스턴트 식품이었다. 굴통조림 가공부산물 유래 분말수프의 주요 지방산은 16 : 0(31.5%), 18 : 0(10.4%) 및 18 : 1n-9(27.4%) 등이었고, 단백질의 화학가는 59.4%이었으며, 주요 무기질은 철이었다. 관능평가 결과 대조구인 열수추출물 분말 수프에 대하여 세척수 분말 수프의 경우 점도, 색조, 향 및 맛과 같은 모든 항목에서 차이가 없었다. 이상의 이화학적 및 관능적 검사 결과로 미루어 보아 굴통조림 가공부산물인 세척수는 분말화하여 배합농도를 적절히 조절하면 우수한 인스턴트 분말 수프의 소재로 이용 가능하다는 결론을 얻었다.

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알칼리 이온수의 의치 미생물에 대한 세정효과에 관한 연구 (Cleansing effect of the alkaline ionized water on microorganisms of the denture surface)

  • 김영미;최유성;조인호
    • 대한치과보철학회지
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    • 제49권2호
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    • pp.138-144
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    • 2011
  • 연구 목적: 본 연구는 최근 개발된 알칼리 이온수 e-WASH의 의치에 부착된 미생물 의치세정 효과에 대해 위상차현미경을 이용한 미생물 관찰법을 통하여 알아보고자 하였다. 연구 재료 및 방법: 실험군 41개, 대조군 26개의 의치를 무작위로 선정하여 실험군에서는 알칼리 이온수e-WASH로, 대조군에서는 수돗물에 5분간 침지 전, 후 의치 내면의 치면세균막을 채취하였다. 위상차현미경으로 구강미생물의 형태적, 종류별 양과 운동성에 대하여 세정 전, 후별 구강미생물의 상태를 관찰하였다. 결과: 1. 알칼리 이온수 e-WASH로 의치를 세정한 실험군에서는 세정 전보다 세정 후 구균의 양, 간균의 양, 간균의 운동성, 실사균의 양, 실사균의 운동성, 콤마/나선균의 양, 콤마/나선균의 운동성 등 모든 조사항목에서 감소하였다 (P<.05). 한편 대조군에서는 구균의 양은 감소하였으나 (P<.05), 다른 조사항목에서는 모두 세정 전, 후 간에 차이가 없었다. 2. 알칼리 이온수e-WASH로 의치를 세정한 실험군에서는 구균의 양, 간균의 양, 간균의 운동성, 실사균의 양, 실사균의 운동성, 콤마/나선균의 양, 콤마/나선균의 운동성 등 모든 조사항목에서 수돗물로 의치를 세정한 대조군보다 각 구강미생물의 양과 운동성이 적게 나타났다 (P<.05). 결론: 위의 결과를 통해 알칼리 이온수 e-WASH가 의치표면의 각종 미생물의 양과 운동성을 효과적으로 감소시키므로 의치세정제로 추천된다.

출토 직물의 세탁 방법에 따른 물성 변화 (Physical Property Change of Old Fabrics Depending on Cleaning Method)

  • 배순화;이미식
    • 복식
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    • 제54권1호
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    • pp.1-10
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    • 2004
  • The purpose of this study was to compare the efficiency of four different cleaning method of silk and to fabrics, which were excavated from the sixteenth century tombs. The four cleaning methods were hand washing in water and hand washing in solvent, washing in ultrasonic cleaner, and using of ultrasonic gun after washing in ultrasonic cleaner. The following is the result of the experiment: ㆍBoth silk and jute fabrics shrank the most after hand-wash in water. This cleaning method decreased their thickness the most but changed their strength the least. However, the color of the fabric changed the most after had-wash in water. This washing method might discolor the dyed fabric, so one must check the condition of the fabric thoroughly before washing it. ㆍThe weight and the thickness of the fabric changed little after ultrasonic cleaning. This cleaning method, therefore. is less efficient than hand-water-wash. The use of ultrasonic gun after ultrasonic wash for partial cleansing enhanced the efficiency a little. Nevertheless, this method left stain around the area where the gun was used, and the injected water could damage the fabric. ㆍThe excavated fabric became softer in the cleaning process as the dirt was washed away. In both cases of silk and jute fabrics cleaning, solvent made the fabric softer than water. Washed in solvent, the fabric did not swell. But water penetrated to the fiber during the cleaning process and made the fabric swell. When the water evaporates, the swollen fiber structure collapses and the fabric become stiff. Ultrasonic wash did not cause much change in the flexibility of the fabric, for this method does not remove the dirt as effectively as the other method.

오존수 및 염소수 세척이 신선편이 당근의 품질 및 미생물억제에 미치는 영향 (Effect of Ozonated Water and Chlorine Water Wash on the Quality and Microbial De-contamination of Fresh-cut Carrot Shreds)

  • 김지강;;임채일
    • 한국식품저장유통학회지
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    • 제14권1호
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    • pp.54-60
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    • 2007
  • 신선편이 당근채 세척시 오존수 사용에 의한 품질 및 안전성 향상 효과를 구명하기 위해 연구를 수행하였다. 세척 당근을 절단한 뒤 100ppm의 염소수에 1, 2회 세척 및 오존발생장치에서 공급되는 초기 오존수 농도 2ppm에서 1,5, 20분 세척한 뒤 $O_{2}$ 투과율 $29.2pmol{\cdot}s^{-1}{\cdot}m^{-2}{\cdot}Pa^{-1}$ 필름으로 포장하여 $5^{\circ}C$에서 3주간 저장되었다. 당근채의 오존수 세척처리는 저장 중 포장내부의 기체 조성, 당근채의 품질 및 미생물 수에 영향을 미쳤다. 오존수 20분 처리는 당근채 저장 중 $CO_{2}$ 농도가 낮고, 경도가 높았으며, 백화지수(WI), 이취발생 및 미생물 수가 적어 가장 높은 관능점수를 나타내며 저장 3주까지 상품성을 유지하였다. 그러나 염소수 1회 세척은 비록 미생물 수는 오존수 20분 처리와 함께 낮게 나타났으나 품질에 있어서 상대적으로 WI와 이취발생이 높아 오존수 20분 보다 품질변화가 심하였다. 따라서 오존수 20분 처리는 신선편이 당근채의 염소 세척을 대체할 수 있는 방법으로 판단되었다.

Reuses Of Wash Water Effluents Of The Ion-Exchanger Units Of Water Demineralization Plant For Economic And Environmental Benefits

  • Miah, Raisuddin
    • 분석과학
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    • 제8권4호
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    • pp.799-806
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    • 1995
  • In industrial field, a large volume of regenerants (acid and caustic soda) and their washing effluents are regularly disposed off from the water demineralization plant during regeneration of the ion-exchanger units. Of these waste effluents, a part of the wash water discharged from the single bed Anion and Mixed Bed units can be utilized at a certain stage of their washing cycles when its conductivity is fallen down and becomes considerably less than that of the input raw water. The main aim of this specific waste effluent utilization is to dilute the TDS concentration of the input raw water (fed into the single bed ion-exchanger units) by blending. The achievement is the increase of the longevity of the production cycles of the I.E. units along with the improvement of the production quality and decrease of the regeneration frequencies. As a result, regenerant consumption would be saved because of the reduction of ionic load in feed water which will ultimately reduce the water purification cost. At the same time, the environment pollution will also be protected to a considerable extent. This operational measure is quite effective and useful specially where high TDS water is demineralized only by single bed ion-exchangers. In such case, the water treatment plant is very often found to suffer from both production quality and quantity in addition to carrying out of random and restless regenerations. Proper reuses of the aforesaid wash water effluents of the Anion and MB units excellently minimizes the difficulties experienced in practice. This paper contains the utilities and techniques of reuses of the different kinds of waste effluents of the industrial water treatment plant in addition to the specific reuses of the post-regeneration wash waters of the Anion and MB ion-exchanger units.

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Aerosol Deposition and Behavior on Leaves in Cool-temperate Deciduous Forests. Part 1: A Preliminary Study of the Effect of Fog Deposition on Behavior of Particles Deposited on the Leaf Surfaces by Microscopic Observation and Leaf-washing Technique

  • Watanabe, Yoko;Yamaguchi, Takashi;Katata, Genki;Noguchi, Izumi
    • Asian Journal of Atmospheric Environment
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    • 제7권1호
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    • pp.1-7
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    • 2013
  • To establish the method for investigating the behavior of aerosol particles deposited on the leaf surface against fog water under natural conditions, scanning electron microscopy with energy-dispersive X-ray (SEM-EDX) analysis and wash water analysis by ion chromatography after the washing treatment were performed using leaves of white birch collected from low part of the tree crown and the top of the tree in Sapporo City, Hokkaido, northern Japan. Each of collected leaves was divided into two parts according to the treatment performed: leaf surface (adaxial side) was 1) untreated, and 2) washed with deionized water with a pipette. In untreated samples, many particles of various shapes, including soil particles and organic debris, were deposited on the surface. Particles containing S were found on the surface of samples collected from only low part of the tree crown. After the washing treatment, SEM-EDX analysis revealed that soil particles and particles containing S had been washed off with water, although some particles such as soil particles and organic debris still remained on the leaf surface. The major anion such as $SO{_4}^{2-}$ was detected in wash water of all samples, although the peak of S in X-ray spectra was not detected from samples collected at top of the tree. The combination of SEM-EDX analysis with wash water analysis indicated that $SO{_4}^{2-}$ was deposited on the leaf surface in dissolved state and/or in state of submicron particles. These results suggested that fog water could remove soil particles and particles containing S and $SO{_4}^{2-}$ from the leaf surfaces, but not all particles. There was no difference in sampling position in the tree crown. Our study suggested that combination with SEM-EDX analysis and wash water analysis would be effective for investigation of the behavior of particles on the leaf surface against fog water.