• Title/Summary/Keyword: Washing time

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Experimental Study on Synthetic Fiber Filled Channel for Treating Turbid Water at the Construction Sites and Protecting Drain System (합성섬유 충진 여과수로를 이용한 건설사업장의 흙탕물 처리 및 배수구 보호에 관한 실험적 연구)

  • Yuan, Qingke;Cheng, Jing;Park, Kisoo;Kim, Youngchul
    • Journal of Korean Society on Water Environment
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    • v.32 no.6
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    • pp.537-545
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    • 2016
  • In order to cope with the new and strict government regulations for turbid water discharge from construction sites, this study tested whether synthetic fiber filters can replace conventional best management practices. The filter efficiency was about 10 to 60% with a varying filter depth of 5 to 15cm, presuming extreme storm flow conditions to be in the range of 800 to 1500m/day of filtration rates. Fiber filter acts exactly like a granular filter, i.e. the separation efficiency is directly and inversely proportional to filter depth and rate, respectively. Based on the operational data, we suggested the Log-Log design relationship, which can be used to determine the filter depth and area. Compared to the widely used gravel filter which treats the turbid water at the construction site, about 20% higher efficiency was obtained under similar operating conditions. Cleaning the filter through a simple hand-washing method at the time of break-through, achieved about 90% soil recovery.

Leaching of lonic Components from the Soil Applied with Swine Slurry (돈분뇨의 토양처리시 이온 성분의 용탈 특성)

  • 김태헌;류성필;김성수;오윤근;허철구
    • Journal of Environmental Science International
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    • v.12 no.3
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    • pp.325-335
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    • 2003
  • An agricultural land application of swine slurry is one of the best management practices in Jeju island whose ground water must be protected. So as to study the effect of appling swine slurry on ground water or aquifer, incubation-leaching technique was used by assuming the incubating period of 1, 2, 4, 8, 16, or 32 days, and application rate of 3200.0 mgT-N/$\ell$ , 820.0 mgT-P/$\ell$, and 1887.0 mgK$\^$+/$\ell$ in swine slurry. The leachates were collected from the soil columns(PVC 30 cm L${\times}$5.5 cm D) packed 15cm in depth with Gangjeong soil series by washing with 100 mL distilled water. The leached components were measured by using ion chromatography far Cl$\^$-/, NO$_3$-N, F$\^$-/, Br$\^$-/, Na$\^$+/, K$\^$+/, Ca$^2$$\^$+/, and Mg$^2$$\^$+/ , atomic absorption spectrophotometry for Fe and Mn, and UV-Vis spectrophotometry for T-N and T-p. Application of swine slurry in naked soil could influence on the ground water or aquifer by increasing nitrate-nitrogen in leachate with time, or leaching the cations present in soils in accompany with anions because of H$\^$+/produced in nitrification. Therefore, careful consideration should be taken about what amount, when, where, and how fur protecting ground water system.

A Study of the Current State of Cyclist Wear (사이클 전문복 착용실태에 관한 연구)

  • Kim, Eun-Kyong
    • Journal of the Korean Society of Costume
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    • v.60 no.5
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    • pp.88-105
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    • 2010
  • The purpose of this study is to grasp the actual wearing conditions, inconvenience and problems with cycle wear. To attain this purpose, a questionnaire was completed by direct observation and by interviewing bicyclists. The questionnaire was given to 273 bicyclists. The questionnaire consisted of items that are related to concerns with dressing appropriately and enhancement of physical performance through dress. Following are the results of this study. According to the survey, many of them purchased imported cycle wear rather than national cycle wear, and the satisfaction according with purchase rate was low. Bicyclists were uneasy with finding right size cycle wear especially for women. It turned out that the area of the knee and elbow are mostly the areas that they get hurt while riding. Even though the knee and elbow are the mostly hurt area, bicyclists do not prefer to wear appropriate protector for the knee and elbow to excel in their performance in cycling. In material related questions, lower dissatisfaction was indicated for the lints caused by fraction. Average satisfaction was indicated for the distortion after washing, changes in color, touch of the fabric, matters with static and sweat. With regard to the areas where the bicyclists felt discomfort was highly indicated with lower-body clothing. Discomfort was highly indicated with crotch area when riding long period of time. Also when riding a cycle, discomfort was indicated with the leggings cuffs when it comes upward with riding motion. Most of the bicyclists felt the tight fitting leggings were embarrassing.

A Study on the improving Dyeing properties of Natural Dyes (천연염료의 염색성 향상에 관한 연구)

  • 서명희
    • Proceedings of the Korea Contents Association Conference
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    • 2004.05a
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    • pp.473-477
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    • 2004
  • Cotton fabric was treated with Cationon UK(tertiary ammonium salt) to improve the dyeability to black tea colorants. In order to investigate the efficacy of Cationon UK for improving dyeing properties of cotton fabric, the effect of Cationon UK treatment conditions and dyeing conditions on dye uptake of the cotton fabrics treated with Cationon UK were examined and the colorfastness to washing, perspiration, rubbing and light was also evaluated for practical uses. Cationized cotton treated with Cationon UK showed high dye uptake at lower dyeing concentration and shorter dyeing time, compared with untreated. Dyeing temperature did not affect significantly dye uptake and the maximum dye uptake was obtained at pH 5. Most colorfastness was relatively good, showing 4/5∼5 rating.

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Rainwater for Water Scarcity Management: An Experience of Woldia University (Ethiopia)

  • ANDAVAR, Venkatesh;ALI, Bayad Jamal;ALI, Sazan Ahmed
    • Asian Journal of Business Environment
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    • v.10 no.4
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    • pp.29-34
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    • 2020
  • Purpose: Town of Woldia, a semi-arid region in the Northern Wollo region of Ethiopia, faces water supply shortage in general, though the town possesses a running stream of clean water throughout the year. This study is aimed at analyzing the possibility of using rainwater for water scarcity and non-potable water needs of the Woldia University. A careful study and analysis have been made to assess the feasibility of using rainwater in place of the tap water supply. Research design and methodology: This study was done inside the main campus of Woldia University located in Woldia town. The runoff water from the roof of buildings was studied, by the time of rainfall in the town. Also, the budget needed for implementing a rainwater harvesting system was calculated. Results: The findings of the study clearly indicates that the requirements of the water to use for flushing, cleaning, and washing toilets in the administrative buildings and classrooms can be satisfied by using rainwater as an alternative to tap water. Conclusion: Based on the results the study finds it is benefitable for the Woldia University to install the rainwater harvesting system at the earliest to solve the water problems prevailing in the current situation.

Effects of Zinc Deficiency on Immune Response in Mouse (식이 아연이 Mouse의 면역 반응에 미치는 영향에 관한 연구)

  • 명춘옥
    • Journal of Nutrition and Health
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    • v.21 no.2
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    • pp.113-121
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    • 1988
  • The purpose of this study was to investigate the effects of dietary zinc on immune response in mice. Weanling male mice was placed individually in stainless steel cages and fed a zinc dificient diet and control diet. All mice were given deionized water ad libitum. The introduction of extraneous zinc was minimized in all cage by washing feed jars and water bottles sequentially with 4mM EDTA and conc-nitiric acid followed by deionized water. After 4 and 5 weeks of the diets, mice were immunized with lx 106 Naegleria fowleri intraperitoneally. Mice were weighed once a week. The results from this study are summarized as followed ; 1) Mice fed the zinc dificient diet showed growth retardation. After 3 weeks of diets, mean body weight of zinc deficient mice was 21.4g and that of control was 25.0g. This difference is singnificant statistically (p<0.01). The more time passed, the more remarkable difference was found. 2) The weigth of organs were measured on liver, kidney, spleen, thymus, heart, lung, brain. Difference in weight were observed only in liver and spleen. 3) Proliferative response of spleen cells of zinc deficient mice to con A was lower than that of control mice after one week on immunization(p<0.005). 4) Stimulation index was lower in zinc deficient mice to phytohemagglutinin after two weeks on immunization (p<0.05). 5) Blastogenesis of speen cells of zinc deficient mice to Naegleria fowleric lysate was lower after 10 days on immunization (p<0.05). 6) Immunoglobulin G antribody titers of zinc deficient mice sera by ELISA was lowered to control mice after 5 weeks on immunization (p<0.005).

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Study on the Limit of Water Content by Cake Filtration and Effective Operation in Filtration-Expression Process (여과에 의한 케이크 함수량의 한계와 효율적인 여과-압착 조작 조건에 대한 연구)

  • Yim, Sung Sam;Song, Yun Min
    • Korean Chemical Engineering Research
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    • v.43 no.6
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    • pp.696-703
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    • 2005
  • The definition of cake is not established for cake filtration, and especially the definition was impossible for the filtration of the floc already sedimented. The definition is proposed with the experimental method named 'filtration-permeation'. The limit of water content which can be achieved with cake filtration of floc was established with the definition of cake. The expression operation of which the purpose is to reduce the water content of pre-formed filter cake is calculated with our 'unified theory on solid-liquid separation' and compared with the experimental results. The importance of expression is analyzed by the calculated whole procedure of cake filtration and expression. The method determining the most effective operational conditions of filter press including the cake discharge and washing time is proposed.

Changes in Physical Properties of Paper by Solvent-Bonding between Cellulose Fibers Using Aqueous Solution of N-Methylmorpholine N-Oxide (N-Methylmorpholine N-Oxide 수용액을 이용한 셀룰로오스 섬유들간의 용제접착에 의한 종이의 물성 변화)

  • 이양헌;박찬헌;이현진;이선희
    • Textile Coloration and Finishing
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    • v.11 no.1
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    • pp.34-41
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    • 1999
  • To examine the increase of paper strength by solvent-bonding using N-methylmorpholine N-oxide (NMMO), a paper was treated with aqueous solutions of NMMO, concentrated at $90^\circ{C}$ for selected periods of time, and pressed for 5 seconds followed by washing and drying. The effect of the increasing NMMO concentration on bonding state and some important properties of samples were mainly investigated. With increasing concentration of NMMO, the degree of bonding between fibers was increased, the fiber cross-sectional shape was changed from 'thin ribbonlike' to 'round rodlike' by swelling with solvent, and the longitudinal waves (crimp) were introduced to fibers, hence the shrinkage, weight per unit area, and thickness of paper were increased. Consequently, the tensile strength and elongation, under standard and wet conditions, and the stiffness were increased, and the water absorption was decreased generally with increasing concentration of NMMO. The moisture regain of treated samples was lower than that of the untreated sample, because of the reduction of space between fibers. But the moisture regain was increased a little with increasing concentration of NMMO due to the fiber swelling with NMMO followed by structural relaxation.

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Wool Dyeing with Sepia Melanin (세피아 멜라닌에 의한 양모 염색)

  • Kim, Su-Jin;Kwon, Hye-Ryun;Yoo, Jung-Hwa;Jang, Jin-Ho
    • Textile Coloration and Finishing
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    • v.22 no.1
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    • pp.14-20
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    • 2010
  • Squid ink was purified to melanin powder by repeated treatments with aqueous sodium hydroxide and acetic acid solutions. The exhaustion dyeing conditions of melanin to wool fabrics were investigated in relation with pH, melanin concentration, dyeing temperature and time. The melanin was dyeable to cotton and wool fabrics but higher dyeability of the wool was observed. A K/S of 7 was obtained on the optimally dyed wool fabrics with 5 % owf melanin under pH 4 at $100^{\circ}C$ for 60 minutes. Color fastness to both washing and rubbing was excellent and color fastness to light was also very good probably due to the polymeric nature of the extracted sepia melanin.

A Study on the Separation of X- and Y- Spermatozoa in Farm Animals (가축에 있어서 X-정자와 Y-정자의 분류에 관한 연구)

  • 고대환;박흠대;정길생
    • Korean Journal of Animal Reproduction
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    • v.3 no.1
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    • pp.41-47
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    • 1979
  • This experiment was carried out to clarify the methods of the F-body test in human and the B-body test in buil and hog. The effect of pH and albumin concentration on the migration of X- and Y- sperm was also investigated. The results obtained were summarized as follows: 1. In the human semen, the frequency of sperm in which an F-body is visible was different by the fluorochrome. Namely, in case of quinacrine mustard, the F-body frequency was 48.8∼43.4 percent (average 49.6%), and in case of quinacrine dihydrochloride, that was 40.7∼50.8 percent (average 42.0%). 2. The frequency of a, pp.rance of B-body was 43.4${\pm}$1.3 percent in bull semen, and 45.5${\pm}$0.7 percent in hog semen. 3. A, pp.arance of B-body in bovine semen was increased due to duration of time after washing till 12 hours. 4. Separation of X- and Y- spermatozoa using diluents with different hydrogen ion concentration was impossible. 5. A, pp.arance of B-body separated in medium with 6, 10 and 20% ovalbumin was 51.1${\pm}$2.4, 50.6${\pm}$2.5 and 58.2${\pm}$3.0 percent, respectively, and those values were significiantly higher (p<0.01) than corresponding control values.

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