• Title/Summary/Keyword: water control

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An Experimental Study on the Application of Measuring Method of Water Content for Quality Control of Concrete (콘크리트 품질관리를 위한 단위수량 측정 기법의 적용성에 관한 실험적 연구)

  • Kim, Yong-Ro;Choi, Il-Ho;Jung, Yang-Hee;Lee, Do-Bum
    • Journal of the Korea Concrete Institute
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    • v.19 no.2
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    • pp.179-188
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    • 2007
  • Recently, the concern on the receipt of poor ready-mixed concrete in the construction field and the durability of concrete has been increased. Based on the such background, a large number of measuring methods of water content for fresh concrete have been developed and enforced in a developed country. In this study, to investigate practicality for quality control of ready-mixed concrete among various water content measurement techniques, microwave range method, air meter method and capacitance measurement method as measuring methods of water content were selected. Then, it was evaluated estimating performance of water content according to the change of binder types, fine aggregate types, absorption ratio, water content and water-binder ratio in series I and II. Also, it was examined influence on error occurrence of water content according to change of properties of used materials in series III. Finally, based on this study, it was proposed fundamental data to utilize measurement technique of water content to quality control of ready-mixed concrete in construction field.

Bio-Green' Functional Water Supply Influences Mineral Uptake and Fruit Quality In Tsugaru Apples (‘바이오 그린’ 기능수 처리가 사과 쓰가루 품종의 무기성분 흡수와 과실품질에 미치는 영향)

  • Kim, Wol-Soo;Chung, Soon-Ju
    • Journal of Bio-Environment Control
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    • v.6 no.2
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    • pp.71-79
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    • 1997
  • Commercial Bio- Green(B.G.) functional water was manufactured through a series of processes : water - ultra-purification - adding catalysts - energy imprinting fermenting with energized water + zeolite and others + photosynthetic bacteria in fermenter longrightarrow filtering. Control(0), 5 or 10 liters per plant of B.G. functional water were supplied to the orchard soil under canopy of 10 year- old ‘Tsugaru’/M26 apple trees on March 20, May 20 and June 20, 1995, respectively. pH and content of Ca and Mg of orchard soil were increased by supply with B.G. functional water. However, P$_2$ $O_{5}$, K, and B contents were not influenced by the treatment. At harvest time soluble solid content of flesh tissue and anthocyanin of fruit skin were increased by the treatment. B.G functional water treatment showed higher root activities, and photosynthesis of leaves than that of control. Also B.G. functional water treatment enhanced Ca content in fruit skin and flesh tissues, whereas not affected N, K, and Mg contents. During storage at 4$^{\circ}C$ cold room, the more volume of B.G. functional water supply showed lower bitter pit symptom. Respiration and ethylene evolution in fruit decreased, while fruit firmness increased by the treatment during storage.

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The State of Water Resources in the Philippines

  • Rubio, Christabel Jane P.;Jeong, Sang-Man;Lee, Joo-Heon
    • Proceedings of the Korea Water Resources Association Conference
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    • 2008.05a
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    • pp.82-91
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    • 2008
  • This paper sought to provide information regarding the water resources in the Philippines, focusing on the issues of water quality, status of water use and water scarcity, and other threats to water availability. Although the country has sufficient amount of water resources, it was found out that water availability is still threatened by some major water resources problems: increasing water demand due to drastic growth in population, water resources pollution, droughts and flooding and weak institutional framework to address these problems. Water quality problems include increasing groundwater and surface water pollution. Moreover, drought and flooding have also increased damages in recent years due to deteriorating watersheds and high economic and population growth. In relation to these, the Government enacted national laws to define and deal with water control and quality management. The objective of this research was to present and evaluate current conditions and issues on Philippine water resources.

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Usable water production from coal seam gas water with a combination of pore control fiber filtration and reverse osmosis

  • Shin, Choon Hwan;Bae, Jun Seok
    • Environmental Engineering Research
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    • v.23 no.2
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    • pp.210-215
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    • 2018
  • Coal seam gas (CSG) water, to be discharged, has been usually treated in reverse osmosis (RO) plants which require extensive and expensive pre-treatment. However, current low gas prices have been a great driver for relevant industries to seek for alternative cost-effective technologies in the aspect of its beneficial use and fit-for-purpose usable water production. In this paper, a combined system with a two-stage pore control fiber (PCF) filtration and a RO system was designed and tested for CSG water treatment. Also, a coagulation reactor was placed in front of the PCF to further enhance suspended solid removal. More than 99% of SS were removed through the PCF filtration while organic, total nitrogen and total phosphorous were mostly removed by the RO system. Especially along with a decrease in conductivity, the total dissolved solid derived from salts was mainly removed in the RO system. Having $OH^-$ undetected, $HCO_3{^-}$ was found to be a dominant compound and its removal efficiency was 97-98% after the RO treatment. And a Fe(III) type of Polytetsu, which was the first to be tested in this paper, was found to be a better option than a Al(III) type of Poly Aluminium Chloride due to its greater coagulation efficiency and applicability at a broader range of pH than the Al(III) type. In addition, there was no noticeable change in oxidation reduction potential, suggesting that an additional process is required to oxidize non-ionic organic carbons (detected as total organic carbon).

Preparation of Asymmetric Membranes by Addition of Nonsolvent (비용매 첨가제를 이용한 비대칭막의 제조)

  • Kim, Nowon
    • Membrane Journal
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    • v.25 no.1
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    • pp.32-41
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    • 2015
  • High performance polysulfone microfiltration membranes with a high were successfully prepared by vapor induced phase separation (VIPS) coupled with non-solvent induced phase separation (NIPS) process. Asymmetric Membranes were prepared with PSF/DMF/PVP/PEG/DMSO/water mixed solutions and water/IPA coagulant. PSF, DMF, PVP, PEG, DMSO, water was used as a membrane polymer, a solvent, a hydrophilic polymer additive, a polar protic liquid polymer, a polar aprotic nonsolvent, and a polar protic nonsolvent in the casting solution, respectively. The addition of polar aprotic nonsolvents, and polar protic nonsolvents is a convenient and effective method to control membrane structure. In order to control the morphology of polymeric membranes, the spontaneous emulsification induced by drawing water vapor into the exposed casting solution surface has been used. Control of the internal morphology of polymeric membranes by using mixed coagulation solution such as water and IPA is discussed in the present work. The pure water permeability, pore size distribution, surface hydrophilicity and membrane morphology were investigated. Due to the addition of DMSO to casting solution, the mean pore size increased almost $0.2{\mu}m$ and the water flux increased about 1000-1800 LMH.

A Study on the Effect of Inflammable Materials on the Control Characteristics of Thermal and Smoke Fluid of Water Curtain System (가연성 물질에 따른 워터커튼 시스템의 열 및 연기유동 제어특성에 관한 연구)

  • You, Woo-Jun;Nam, Jun-Seok;Kim, Dong-Joon;Lee, Jeong-Kyoon;Ryou, Hong-Sun
    • Fire Science and Engineering
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    • v.26 no.2
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    • pp.53-58
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    • 2012
  • In this study fire control characteristics for inflammable materials of water curtain system are experimentally analyzed. Heat release rate for pinewood and gasoline was calculated using Room Corner Tester (RCT) and fire test apparatus for water curtain system is manufactured. Nozzles (180 degree of injection angle, 8.2 mm of orifice diameter) are installed at the nearby ceiling of place at 5 m distance from fire originate and temperature profile as well as transmission are obtained from the fire experiment of pinewood and gasoline in the water curtain system. Based on the results, parameters of engineering importance for fire control characteristics of water curtain system such as generation of high temperature smoke and thermal phenomena of fluid flow by injection nozzle are identified.

The Physiological Activities of Kyung Ok-Ko(II) -Effects on the Hyperglycemia, Hypertension, Anti-Fatigue and Decrease of Body Weight- (경옥고의 생리활성 (II) -고혈당, 고혈압, 지구력 및 체중감소에 미치는 영향-)

  • Whang, Wan-Kyunn;Oh, In-Se;Lee, Suk-Hee;Choi, Soo-Bu;Kim, Il-Hyuk
    • Korean Journal of Pharmacognosy
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    • v.25 no.1
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    • pp.51-58
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    • 1994
  • The studies were conducted to investigate the anti-diabetic activities on the hyperglycemia induced by streptozotocin in rats, anti-hypertensive activities in SHR, anti-fatigue and decrease of body weight activities in mice by Kyung Ok-Ko water extract and drink, which is a traditional preparation in Korea. 1. The blood glucose levels of streptozotocin-induced hyperglycemic rats were dose-dependently decreased by administrations of various doses(300, 600, 1200 mg/kg) of Kyung Ok-Ko water extract. Particularly, administration of 600, 1200 mg/kg were significantly shown to decrease glucose levels comparing with control group. 2. The serum total cholesterol levels of streptozotocin-induced hyperglycemic rats were dose-dependently decreased by administrations of various doses(300, 600, 1200 mg/kg) of Kyung Ok-Ko water extract. Particularly, administration of 600, 1200 mg/kg were significantly shown to decrease total cholesterol levels comparing with control group. 3. The serum triglyceride levels of streptozotocin-induced hyperglycemic rats were dose-dependently decreased by administrations of various doses(300, 600, 1200 mg/kg) of Kyung Ok-Ko water extract. Particularly, administration of 600, 1200 mg/kg were significantly shown to decrease triglyceride levels comparing with control group. 4. The blood pressure in SHRs were dose-dependently lower descended by administration of Kyung Ok-Ko water extract 300, 600, and 1200 mg/kg, respectively. 5. The swimming time of Kyung Ok-Ko water extract(100, 200, 400 mg/kg) and drink(0.7, 1.4, 2.1 ml/kg) were significantly extended to all experimental group dose-dependantly. 6. The decrease of body weight of Kyung Ok-Ko water extract(100, 200, 400 mg/kg) and drink(0.7, 1.4, 2.1 ml/kg) were significantly evaluated dose-dependently in all experimental group.

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Selection on Tolerant Oak Species to Water Flooding for Flood Plain Restoration (홍수터 복원을 위한 침수 내성 참나무 수종 선발)

  • Han, Seung-Ju;Kim, Hyea-Ju;You, Young-Han
    • Journal of Wetlands Research
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    • v.11 no.2
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    • pp.1-7
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    • 2009
  • In order to select the water flooding-tolerant trees among Korean oaks, we cultivated the sapling of 6 deciduous oak species, Quercus acutissima, Q. mongolica, Q. variabilis, Q. dentata, Q. aliena and Q. serrata, under the water flooding treatment and the control, and analysed the growth difference among them. For comparing the growth between treatment and control, we measured 13 morphological and ecological traits, such as leaf Leaf number, leaf length, leaf width, leaf area, shoot length, stem length, stem diameter, root length, plant length, leaf weight, stem weight, root weight, plant weight. Q. serrata have no growth difference between water flooding treatment and control, but the rest 5 species showed the growth reduction in water flooding treatment. Tolerance of oak species to water flooding was risen in order of Quercus acutissima, Q. mongolica, Q. variabilis, Q. dentata, Q. aliena and Q. serrata. Thus, among Korean deciduous oaks, it is desirable to plant Q. serrata for flood plain restoration of river.

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Effect of Solvents on Physical Properties and Release Characteristics of Monolithic Hydroxypropylmethylcellulose Matrix Granules and Tablets

  • Cao Qing-Ri;Choi Yun-Woong;Cui Jing-Hao;Lee Beom-Jin
    • Archives of Pharmacal Research
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    • v.28 no.4
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    • pp.493-501
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    • 2005
  • Effect of solvents on physical characteristics and release characteristics of monolithic acetaminophen (APAP) hydroxypropylmethylcellulose (HPMC) matrix granules and tablets were examined. Various types and amounts of solvents were employed for granulation and coating. APAP and other excipients were mixed and were then wet-granulated in a high-speed mixer. The dried granules were then directly compressed and film-coated with low viscosity grade HPMC. As the amount of water increased, the size of granules also increased, showing more spherical and regular shape. However, manufacturing problems such as capping and lamination in tableting occurred when water was used alone as a granulating solvent. The physical properties of HPMC matrix granules were not affected by the batch size. The initial release rate as well as the amount of APAP dissolved had a tendency to decrease as the water level increased. Addition of nonaqueous solvent like ethanol to water resulted in good physical properties of granules. When compared to water/ethanol as a coating solvent, the release rate of film-coated HPMC matrix tablets was more sensitive to the conditions of coating and drying in methylene chloride/ethanol. Most of all, monolithic HPMC matrix tablet when granulated in ethanol/water showed dual release with about $50\%$ drug release immediately within few minutes followed by extended release. It was evident that the type and amount of solvents (mainly water and ethanol) were very important for wet granulation and film-coating of monolithic HPMC matrix tablet, because the plastic deforming and fragmenting properties of material were changed by the different strengths of the different solvents.