• Title, Summary, Keyword: effect of water

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A Study on Predicting the Range of Cooling Effect and the Diffusion of Water Particles that are Generated from a Fountain (분수에서 생성되는 물입자의 확산과 냉각효과의 범위 예측)

  • Lee, Sang-Deug
    • Journal of Environmental Science International
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    • v.20 no.7
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    • pp.819-828
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    • 2011
  • This research was done to clarify the cooling effect of water particles generated from a fountain. This effect is a one way to control the heat island effect of big cities. The result of this research was drawn by setting the jets of water in a certain height, and then studying the diffusion of water particles, which is affected by the size of the particles and the wind speed, and the cooling effect caused by the diffusion. 1) When a diameter of a water drop was 500 ${\mu}m$ and the wind speed was 2.0 to 6.0 m/sec, the water drop diffused 75 to 190m, and the water vapor spread over 175 to 440 m. As a result, there was more than $0.5^{\circ}C$ of cooling effect on the temperature in the atmosphere 130 to 330m around the water fountain. 2) When a diameter of a water drop was 750 ${\mu}m$ and the wind speed was 2.0 to 6.0 m/sec, the water drop diffused 65 to 150 m, and the water vapor spread over 160 to 405 m. Moreover, there was more than $0.5^{\circ}C$ of cooling effect on the temperature in the atmosphere 110 to 275 m around the water fountain. 3) After studying on the relationship between the diameter of water drop and the wind speed, and the diffusion of water particles and the range of the atmosphere that was cooled, a result could be drawn from the research that the smaller the diameter of the water vapor gets and the faster the wind speed becomes, the wider the water particles diffuse and the cooler the atmosphere around the fountain becomes. 4) This research further extrapolates that when the ordinary water(tap water, water from river and stream) is used in a fountain, the cooling effect of the air near the fountain can be approached similarly. If the seawater is used in a fountain, there is to be more to concern not only on cooling effect on the air, but also on other effects on surrounding environment generated by the salt in seawater.

Antibacterial Effect of Electrolyzed Water on Oral Bacteria

  • Lee Sung-Hoon;Choi Bong-Kyu
    • Journal of Microbiology
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    • v.44 no.4
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    • pp.417-422
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    • 2006
  • This study investigated the antibacterial effect of electrolyzed water on oral bacteria both in vitro and in vivo. Tap water was electrolyzed in a water vessel using platinum cell technology. The electrolyzed tap water (called Puri-water) was put in contact with five major periodontopathogens or toothbrushes contaminated with these bacteria for 30 sec. In addition, Puri-water was used as a mouthwash for 30 sec in 16 subjects and the antibacterial effect on salivary bacteria was evaluated. Puri-water significantly reduced the growth of all periodontopathogens in culture and on toothbrushes, and that of aerobic and anaerobic bacteria in saliva, when compared to the effect of tap water. It also significantly reduced mutans streptococci growing on mitis salivarius-bacitracin agar. Our results demonstrate that the electrolyzed tap water is effective as a mouthwash and for toothbrush disinfection.

Effect of Livestock Liquid Manure Released at a Rice Field on Quality of Soil and Water in the Saemangeum Watershed (가축분뇨 액비 살포가 새만금유역에서의 논토양과 수질에 미치는 영향)

  • Kim, Mi-Sug;Kwak, Dong-Heui
    • Journal of Korean Society of Water and Wastewater
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    • v.30 no.1
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    • pp.19-31
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    • 2016
  • The Saemangeum watershed is required to manage water pollution effectively but the effect of liquid manure (LM) on soil and water quality in the basin is not clearly identified as yet. This study aims at assessing the effect on soil of a rice field and water quality of water bodies near the rice field during rice-crop time period to find out the effect of LM, the effect of rainfall, and the effect of rice-crop environment on soil and water quality by analyzing data of nitrogen components. As a result of the LM distribution, $NO_3-N$ was much higher than other N components in the entire soil layers and it was accelerated by rainfall right after the LM distribution. Compared to chemical fertilizer (CF), LM was slightly affected but still influenced on the surface water quality. During weak rainfall, low nitrogen concentration in topsoil was resulted as NH3-N decreased and Org-N and $NO_3-N$ increased. $NO_3-N$ concentration in the water of irrigation canals increased with time. During intensive rainfall, $NO_3-N$ and Org-N of the soil were measured highly in the submerged condition, while the water quality of the rice field was lower due to flooding into the irrigation canal as well as the growth of the rice plants. Also, total nitrogen was increased more than 7 times and it showed serious water quality deterioration due to LM and excessive fertilizer distribution, and rainfall during all rice-crop processes. The effect of LM on water quality should be studied consistently to provide critical data while considering weather condition, cropping conditions, soil characteristics, and so on.

The Effect of Water Vapor Addition on the Ignition Delay of Iso-octane/Air Mixture (Iso-Octane/공기 혼합기에서 수증기 첨가가 점화지연시간에 미치는 영향)

  • Baik, Dong-Hoon;Lee, Su-Ryong
    • Journal of the Korean Society of Mechanical Technology
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    • v.20 no.5
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    • pp.600-605
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    • 2018
  • The effect of water vapor addition on the ignition delay of iso-octane/air mixture was numerically investigated with detailed chemical reaction mechanism. The Chemkin-III was utilized to evaluate the delay time of autoignition for isobaric conditions. By dilution effect and thermal effect, water vapor addition increases the ignition delay time. However, the chemical effect by adding water vapor makes the ignition delay shortened. The ignition delay by the chemical effect is reduced by two ways. Dissociation of water vapor increases the quantities of OH and H. One way is that OH directly makes the rate of iso-octane oxidation reaction 2 increase. The other is that $HO_2$ is produced more by three-body reaction, $H+O_2+M{\rightarrow}HO_2+M$, which makes the rate of iso-octane oxidation reaction 3 increase. All trends of three effects are similar according to water vapor addition.

The Self-healing and Ageing Effect of OPC-GGBFS Cement in Sea-water and Tap-water (해수와 담수에서 OPC-GGBFS 시멘트의 자기치유와 재령효과)

  • Kim, Tae-Wan;Kang, Choonghyun
    • Journal of the Korea Concrete Institute
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    • v.29 no.1
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    • pp.11-21
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    • 2017
  • The paper presents experimental results of self-healing effects of OPC-GGBFS paste with cracked and uncracked specimens. The self-healing of cracked specimens is processes of crack closing with re-hydration of unhydrated in crack surface. The OPC paste with GGBFS replacement ratios of 0%, 10%, 20% and 30% were prepared having a constant water-binder ratios of 0.5. The OPC-GGBFS paste specimens immersed in tap-water and sea-water. The temperature of tap and sea-water was $5^{\circ}C$, $15^{\circ}C$ and $25^{\circ}C$. The cracked specimens after deterioration were immersed for 60 days. The relationship between self-healing effect and age-effect was calculate based upon the experimental results. The self-healing effect was measured in ultrasonic pulse velocity (UPV) before and after loading. When the relative change rate of UPV is increases with the increase in GGBFS replacement ratios. Moreover, the self-healing effect is increased with the temperature of tap-water is increase. But the cracked specimens immersed in sea-water was unclear effects of different temperature. Furemore, most of the healing for OPC-GGBFS specimens immersed in tap-water and sea-water occurred during the first 30 days. The self-healing effect until 30 days is higher than that the age-effect. After 30 days, self-effect and age-effect was largely decreases. SEM/EDS analysis of crack on the surface of the specimens in tap-water were covered with aragonite, and sea-water were covered with brucite.

Effect of C Factor Errors on the Analysis of Water Distribution Systems (C계수의 추정오차가 배수관망해석에 미치는 영향)

  • Hyun, In Hwan;Lee, Cheol Kyu
    • Journal of Korean Society of Water and Wastewater
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    • v.13 no.2
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    • pp.23-33
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    • 1999
  • This study is to investigate the effect of C factor errors on the analysis of water distribution systems. For this purpose, an artificial distribution network and a real distribution network were selected as the study networks. Results are as follows. 1. The C factor of a pipe which has small velocity didn't give significant effect on the analysis of a water distribution system. 2. The effect of decreased value of C factors give more influence on the analysis of water distribution systems than that of the increased values. 3. For the C factor calibration, errors of the residual water heads as well as those of the head losses should be considered together. 4. In the analysis of water distribution systems, changes of C factors can give influences only on the nodes which locate behind the pipe. Therefore, this characteristics should be considered in the selection of nodes for the measurement of water heads.

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The Effect of Vegetable Extracts on the Activity of Alcohol Dehydrogenase from Saccharomyces cerevisiae

  • Jung, Soon-Teck;Kang, Bae-Kwang
    • Preventive Nutrition and Food Science
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    • v.6 no.4
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    • pp.224-229
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    • 2001
  • We investigated the effects of bean sprouts (Glycine max), dropwort (Oenanthe javanica), and radish (Raphanus sativus var. hortensis for. acanthiformis) extracts on alcohol dehydrogenase (ADH). The extracts from three kinds of vegetables were prepared by extracting with boiling water, distilling water, and ethyl alcohol. Among extracts, boiling water extract showed the highest activating effect on ADH, respectively and distilled water extract had a greater effect on ADH activation than that of alcohol extract. The ADH facilitating effect of bean sprout extract by distilled water was significantly higher than dropwort or radish, hut the effect of the bean sprout extract by ethyl alcohol was lower than others. The facilitating effect on ADH of mixture extracts of bean sprout and dropwort were mixed at 1 : 1 mixture of boiled-water extract showed the highest effectiveness. And bean sprout extract separated below 3000 molecular weight (MW) range of extract fraction had greater ADH activity than large MW parts.

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Water conservation effect of concave greenroof system and its influential factors (오목형 옥상녹화의 수자원확보효과와 영향인자)

  • Baek, So-Young;Han, Moo-Young
    • Journal of Korean Society of Water and Wastewater
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    • v.29 no.2
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    • pp.165-169
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    • 2015
  • Green roofs are gaining much interest in many cities around the world due to its multi-purpose effects of water conservation, flood mitigation and aesthetic benefits. However it may cause additional water demand to maintain green plants, which may intensify the current and future water shortage problems. While ordinary concrete roofs and normal green roof drains off rain water, concave green roof system can retain rain water because of its water holding capability. In this study, the water conservation effect of concave green roof was compared to normal roof on #35 building in Seoul National University, Seoul, Korea. For seven rainfall events the amount of stored rainwater and runoff were measured and proved water conservation effect of the concave green roof system. The concave green roof system of which area is 140m2 showed effect of water conservation from 1.8ton to 7.2ton and the most influence factors on water conservation in green roof are rainfall and antecedent day. If this concave green roof is applied to many buildings in the cities, it is expected as a way to water conservation through rainfall storage.

The influence of flow rate and temperature on the quenching effect of cooling water (냉각수의 유동속도와 온도가 담금효과에 미치는 영향)

  • 민수홍;김상열
    • Journal of the korean Society of Automotive Engineers
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    • v.4 no.3
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    • pp.24-39
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    • 1982
  • It has already been known that quenching effect is influenced greatly by stirring and changing coolant's temperature on quenching. But according to the past investigations its effect has not been taken into consideration quantitatively in the cooling process. The purpose of this study is that the influence of flow rate and temperature on the quenching effect of cooling water as quenching medium is quantitatively examined by using the open channel. The stream of water in this study is turbulent flow. The temperature of the specimen made of pure copper is measured by CA thermocouple in the vicinity of the surface and recorded by an automatic recorder during the quenching process in city water. The results obtained are as follows; 1. The quenching effect of cooling water generally increases with Reynolds Number(characteristic length; specimen diameter)as shown in the experimental formula; but at the realm of Reynolds Number from 1.2 * 10$^{4}$ to 9.2 * 10$^{4}$, the increasing rate of quenching effect shows little increase. 2. The increasing rate of quenching effect was increased under the flow rate of 221 cm/sec. On the other hand, it was decreased below this flow rate. 3. The quenching effect was influenced by the water temperature and the flow rate. But it was rather dependent upon the former than the latter. 4. Although the quenching effect appeared loosely in the water temperature of 50.deg. C, it was shown that the quenching effect increased in the low flow rate of 31 cm/sec. comparing with the still water. 5. It is desirable to design the quenching system to be over 1.2 * 10$^{4}$ in Reynolds Number or over, 3000$cm^{-1}$ / in V/v in order to increase the quenching effect of the system using open channel.annel.

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Studies on the Effect of Guichoolpajing-Tang and Gamiguichoolpajing-Tang (징하에 응용(應用)되는 귀출파징탕과 가미귀출파징탕의 효능(效能)에 관(關)한 연구(硏究))

  • Song, Seog-Ho;Song, Byoung-Key;Lee, Kyoung-Sup
    • THE JOURNAL OF KOREAN ORIENTAL ONCOLOGY
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    • v.1 no.1
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    • pp.213-230
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    • 1995
  • The present work was done to investigate the pharmacological effectiveness of Guichoolpajing-Tang and Gamiguichoolpajing-Tang. The extracted water of those two prescription were administered to experimintal animals and determined analgesic, anti-pyretic, anti-inflammatory effects and effects on intravascular coagulation, spontaneous morements of the isolated rat uterus, the uterine contracion induced by oxytocin or $PGF_{20}$, lifespan of mice implanted intraperitoneally with Sarcoma 180. The following results were obtained. 1) The extracted water of Guichoolpajing-Tang and Gamiguichoolpajing-Tang were revealed significant analgesic effect. 2) The extracted water of Guichoolpajing-Tang and Gamiguichoolpajing-Tang showed anti-pyretic effect. 3) The extracted water of Guichoolpajing-tang and Gamiguichoolpajing-Tang showed anti-inflammatory effect. Especially, the extracted water of Gamiguichoolpajing-Tang showed more significant dffect than another. 4) Concerning the degree of concentration of FDP, Gamiguichoolpajing-Tang treated groups tevealed significant decreases. 5) The extracted water of both prescriptions revealed uterus relaxation on the spontaneous movement of the isolated rat uterus and showed uterine contraction induced by oxytocin or $PDF_{2}$. Especially Guichoolpajing-Tang showed more significant effect than another. 6) The extracted water of both prescription both prescriptions showed effect on lifespan of mice implanted intraperitoneally with Sarcoma 180.

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