• Bulletin of the Korean Chemical Society
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• v.24 no.6
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• pp.695-702
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• 2003

Recent experimental and theoretical advances on the aromatic alcohol-water clusters are reviewed, focusing on the structure of the hydrogen bonding between the alcoholic OH group and the binding water molecules. The interplay of experimental observations and theoretical calculations for the elucidation of the structure is demonstrated for phenol-water, benzyl alcohol-water, substituted phenol-water, naphthol-water and tropolone -water clusters. Discussion is made on assigning the role (either proton-donating or -accepting) of the hydroxyl group by measuring the shifts of infrared frequency of the OH stretching mode in the cluster from that of bare aromatic alcohol for the experimental determination of the cluster structure.

• Bulletin of the Korean Chemical Society
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• v.29 no.5
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• pp.1048-1050
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• 2008

Electric current flow was observed through imogolite film when imogolite ($(HO)_3Al_2O_3SiOH$) was exposed to water molecules and connected to external electrodes. Current flow was due to the bound water on the surface of imogolite. Current flow increased as the pH of the water decreased. The current-voltage (I-V) measurements from a field effective transistor (FET) using $H_2O$/imogolite film revealed that the current carrier in $H_2O$/ imogolite had p-type characteristics, i.e. the carrier was probably $H^+$. The possible mechanism for current transportation in imogolite/water was also suggested in this paper.

• 수도
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• s.24
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• pp.7-29
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• 1981

• Korean Journal of Environmental Agriculture
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• v.35 no.1
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• pp.15-23
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• 2016

BACKGROUND: Water quality is of concern to water utility operators, public health officials, and populations using the water. If any contaminant is released from a point of entry, it could be spread rapidly throughout the water stream. So the identification of the location of the points of entry and its release history are critical informations to establish the management strategy.METHODS AND RESULTS: Aniline, nonylphenol, pentachlorophenol and formaldehyde in 39 surface water samples were analysed using Gas chromatography-mass spectrometry (GC-MS) methods. Formaldehyde, aniline and nonylphenol were mainly detected in the near sites where industrial waste water and domestic sewage were discharged into stream. But pentachlorophenol was detected in the downstream samples where pulp manufacturing plants were operated.CONCLUSION: Results indicate that pentachlorophenol found in main stream of Guem river was mainly introduced from pulp manufacture industries. Otherwise, formaldehyde, aniline and nonylphenol were mainly contaminated from the industrial waste water and domestic sewage.

• Bulletin of the Korean Chemical Society
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• v.33 no.4
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• pp.1345-1348
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• 2012

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
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• 2005.04a
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• pp.405-407
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• 2005

To evaluate the main hydrogeochemical characteristics, river waters are investigated using element리 and isotopic compositions in South Korea. In this area, the chemical compositions are mostly classified into three groups; $Ca^{2+}-{HCO_3}^-$ type, $Ca^{2+}-Cl^{-}-{NO_3}^-$ type and $Ca^{2+}-{HCO_3}^{-}-Cl^{-}-{NO_3}^-$ type. These types are affected by two major factors: water-rock interaction and anthropogenic inputs such as sewage and fertilizers. Based on the values of ${\delta}^{18}O$ and ${\delta}D$, most of waters are originated from precipitation except two samples contaminated. The lithology and geography of basins mainly control the water chemistry. Elemental and isotopic compositions show that water chemistry are mainly controlled by three end members, especially by carbonate dissolution, and suggest that anthropogenic input affect the water chemistry. Also, three weathering sources are identified: silicates, dolomite and limestone.

• Proceedings of the KSEEG Conference
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• 2004.12a
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• pp.9-28
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• 2004

Concern about arsenic is increasing throughout the world, including areas of the United States. Elevated levels of arsenic above current drinking-water regulations in ground and surface water can be the result of purely natural phenomena, but often are due to anthropogenic activities, such as mining and agriculture. The current study correlates arsenic speciation in acid mine drainage and mining influenced water with the important water-chemistry properties Eh, pH, and iron(III) concentration. The results show that arsenic speciation is generally in equilibrium with iron chemistry in low pH AMD, which is often not the case in other natural-water matrices. High pH mine waters and groundwater do not 짐ways hold to the redox predictions as well as low pH AMD samples. The oxidation and precipitation of oxyhydroxides depletes iron from some systems, and this also affects arsenite and arsenate concentrations differently through sorption processes.

• Bulletin of the Korean Chemical Society
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• v.3 no.2
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• pp.50-55
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• 1982

A study of small water clusters composed of two to seven molecules has been performed by using the revised empirical potential function for conformational analysis (REPFCA). Various structures of clusters have been investigated and the relative probability of cluster per molecule is discussed. In general, cyclic structures of water clusters are more favorable than open structures. It is found that cyclic pentamer is the most favorable unit structure in the water cluster.

• Bulletin of the Korean Chemical Society
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• v.32 no.4
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• pp.1407-1410
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• 2011

• Journal of Industrial and Engineering Chemistry
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• v.68
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• pp.416-424
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• 2018

Oil spill and oily wastewater have now become a serious threat to the freshwater and marine environments. Porous materials with super-hydrophobicity and super-oleophilicity are good candidates for the oil adsorption and oil/water separation. Here, flexible hybrid nanofibrous membrane (FHNM) containing $SiO_2$/polyvinylidene fluoride (PVDF) microspheres was prepared by simultaneous electrospinning and electrospraying. The obtained FHNM combined the flexibility of the nanofiber mat and super-hydrophobicity of the microspheres, which could not be achieved by either only electrospinning or only electrospraying. It was found that when the weight ratio between the $SiO_2$ and PVDF reached a critical value, the $SiO_2$ nanoparticles were present on the PVDF microsphere surface, significantly improving the surface roughness and hence the contact angle of the FHNM. Compared with the pure electrospun PVDF nanofiber mat, most of the FHNMs have a higher oil adsorption capacity. The FHNM could separate the oil with water quickly under the gravity and displayed a high efficiency and good reusability for the oil/water separation. More importantly, the FHNM could not only separate the oil with the pure water but also the corrosive solution including the salt, acid and alkali solution.