• Clean Technology
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• v.6 no.1
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• pp.79-84
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• 2000

In this study, to reduce the consumption of chemicals in cleaning processes, Si-wafers contaiminated with metallic impurities were cleaned with electrolyzed water(EW), which was generated by the electrolysis of a diluted electrolyte solution or ultra pure water(UPW). Electrolyzed water could be controlled for obtaining wide ranges of pH and ORP(oxidation-reduction potential). The pH and oxidation-reduction potential of anode water and cathode water were measured to be 4.7 and +1000mV, and 6.3 and -550mV, respectively. To analyze the amount of metallic impurities on Si-wafer surfaces, ICP-MS was introduced. Anode water was effective for Cu removal, while cathode water was more effective for Fe removal.

• Journal of the Korean Society of Tobacco Science
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• v.4 no.2
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• pp.3-10
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• 1982

This experiment was conducted to study the effect of soil water potenial on the growth and internal changes of stressed plants. The experimental imposition of soil water potential ( $\Psi$soil) were -0.1 to -0.2, -0.2 to -0.5, -0.5 to -3.0, -3.0 to -10.0 bar respectively. During water stress all growth rates were depressed, and the most sensitive period to water stress was found to be 10 to 25 days after transplanting. The water potential of leaf was declined rapidly within 12 hours after with holding of water. Nitrate reductase activity was decreased progressively as water deficit was built up in tobacco leaves, but the activity of alpha- amylase and super contents were increased. There were differences in peroxidase isozyme patterns between tile control and water stressed plant. New isozymes started to appear as tobacco leaf water potential decreased.

• Korean journal of applied entomology
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• v.20 no.1 s.46
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• pp.37-41
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• 1981

Mycelial growth and production of macroconidia by Cylindrocladium crotalariae on either PDA or water agar containing soybean leaf pieces adjusted to different water potentials with KCI. were consistently maximal at -14bars. Mycelial growth by this fungus was nii at about -100 bars and below at 30C, -80 bars and below at 25C and -64 bars and below at 20C. Sporulation was prevented at -64 bars and below at $20^{\circ}C\;and\;25^{\circ}C$. Perithecial andmicrosclerotial formation was maximal at abot -1.4 to - 3.0 bars (the basal medium without sait). Percentage of spore germination for this fungus was uniformly maximal at all water potentials between -1.4 bars (the highest tested) and - 20 bars, was progressively less as the water potential lowered below -20 bars, and was prevented at - 60 bars.

• Journal of Korean Society on Water Environment
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• v.26 no.3
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• pp.525-531
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• 2010

To figure out the importance of temperature on electrochemical properties in water environment, calcium carbonate, one of important substances in water chemistry, was chosen to make suspensions. The result of electrokinetic potential of calcium carbonate suspensions revealed that it tended to increase as temperature increased. In addition, electrokinetic potential was negatively increased as suspensions became more basic. Its isoelectric point was ca. 7 regardless of temperature. The adsorption of hydrogen ions on calcium carbonate particles followed endothermic reaction. This result was verified by continuously measuring pH as adding HCl solution in calcium carbonate suspension. It explained that suspensions' potential was determined by DLVO theory which calculated total interaction energy between particles. Suspensions' total interaction energy was proportional to the value of electrokinetic potential. Furthermore, total interaction energy between particles increased as suspensions' temperature was increased.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.41 no.5
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• pp.569-577
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• 1996

This experiment was conducted to investigate the effects of water potential by PEG treatment on germination and quantitative changes of seed storage reserves of soybean [Glycine max (L.) Merr.], peanut(Arachjs hypogaea L.) and corn(Zea may L.). Water potential of PEG(M.W. 10, 000) solution as germination media was 0.0, -0.2, and -0.5MPa. The highest moisture uptake rate was found in soybean seedlings among three crops. Moisture content of seedlings of three crops was decreased at -0.5MPa treatment and seedling length was delayed with water potential decrement. As water potential decreased, decreasing rate of protein content of the seedlings compared to seeds was declined in soybean and peanut. Decreasing rate of starch content of the seedlings was decreased in corn at -0.5MPa treatment. Increasing rate of sugar content of the seedlings was markedly decreased at -0.5MPa treatment in all crops. The results of this experiment showed that availability of moisture and synthesis of sugar for seed germination were influenced below -0.5MPa water potential in three crops.

• Journal of Environmental Health Sciences
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• v.35 no.5
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• pp.376-385
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• 2009

The characteristics of Lake Cheonhoji water and sediment were investigated in oder to utilize these as fundamental materials for the management of lake water quality. The hydrographic properties of Lake Cheonhoji which are relatively low chance of nutrients loading from the watershed and a long retention time of lake water, lead to the probability of high lake productivity. It was also observed that lake water showed stratification during summer and complete mixing during fall, even though water depth was relatively shallow. The trophic state was eutrophic to hypertrophic from summer to late fall. The overall properties of the sediment were oligohumic, high ignition loss and high composition of NAIP and Resid.-P, which might serve as potential pollution sources of lake water quality. In laboratory scale experiments, it was observed that leaching potential of nutrients in the sediment was greatly dependant upon water temperature and dissolved oxygen. Finally, water pollution in Lake Cheonhoji was considered to be largely due to the adverse cycle of uncontrollable eutrophication, which resulted in the subsequent occurrence of dead algae and animal plankton, organic sedimentation, reduction of dissolved oxygen and nutrients leaching, which again reinforced the cycle of eutrophication in the lake.

• Journal of Environmental Science International
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• v.25 no.1
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• pp.173-179
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• 2016

Leaf water and osmotic potential, chlorophyll content, photosynthetic rate, and electrolyte leakage were measured to evaluate tolerance to water stress in wild-type (WT) and transgenic tobacco plants (TR) expressing copper/zink superoxide dismutase (CuZnSOD) and ascorbate peroxidase (APX) in chloroplasts. Leaf water potential of both WT and TR plants decreased similarly under water stress condition. However, leaf osmotic potential of TR plants more negatively decreased in the process of dehydration, compared with WT plants, suggesting osmotic adjustment. Stomatal conductance (Gs) in WT plants markedly decreased from the Day 4 after withholding water, while that in TR plants retained relatively high values. Relatively low chlorophyll content and photosynthetic rate under water stress were shown in WT plants since $4^{th}$ day after treatment. In particular, damage indicated by electrolyte leakage during water stress was higher in WT plants than in TR plants. On the other hand, SOD and APX activity was remarkably higher in TR plants. These results indicate that transgenic tobacco plants expressing copper/zink superoxide dismutase (CuZnSOD) and ascorbate peroxidase (APX) in chloroplasts improve tolerance to water stress.

• Journal of Environmental Impact Assessment
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• v.4 no.1
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• pp.17-23
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• 1995

To assess preliminarily the contamination potential of water resources including groundwater owing to the hydrogeological characteristics of landfill site and the potential impact to humans and animals through contamination of water resources by leachate, "Landfill Site Preliminary Assessment Model(LASPAS)" was contrived. LASPAS could help them proritization of remediation of landfil sites by the convenient and relatively simple evaluation method of landfill site features. LASPAS was designd to aliot numerical ratings to landfill site related factors undermentioned; 1) hydrogeological factors such as hydraulic conductivity of aquifer, thickness of confining layer over aquifer, topographical slope, net recharge, and subsurface containment 2) water resources contamination factors of impacts on receptors such as proximity to drinking water supply, substitutability of drinking water supply, type of use of water resources, known impact on drinking water supply, and flood potential.

• Journal of Korean Society of Water and Wastewater
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• v.18 no.4
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• pp.522-528
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• 2004

Microfiltration with in-line rapid coagulation for drinking water production was examined. The in-line rapid coagulation was conducted using newly developed mixing device instantaneous flash mixer. The flux decline during membrane filtration was monitored with coagulant dosage varied. Flux decline was minimized at 1.1mg/L of coagulant dosage, where streaming potential of coagulated water was near zero. The optimum dosage for the process control was explained by dimensionless distance (${\kappa}{\times}a$) of particle pairs, obtained from electrophoresis parameter describing electrostatic repulsion relative to Van der Waals energy between particle pairs in the pre-coagulated water.

• KOREAN JOURNAL OF CROP SCIENCE
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• v.39 no.2
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• pp.139-145
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• 1994

This study was intended to obtain the basic information on the germination status, changes of $\beta$-amylase activity and reducing sugar contents during seed germination of barley after an imposition of water stress by adding Polyethylene glycol solution. The effects of water deficit on germination were to be decreased in germination rate and velocity. Respiratory Quotient was increased as the osmotic potential in culture solution was decreased. But $\beta$-amylase activity and reducing sugar contents were decreased and the ratio of dry to fresh weight of germinated seeds was increased as the osmotic potential of the culture solution was decreased.