• Korean Chemical Engineering Research
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• v.60 no.4
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• pp.525-534
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• 2022

In this study, we investigated the applicability and optimal operating strategy of a closed-loop pressure retarded membrane distillation (PRMD) for brackish water desalination. For effective operation with net power generation, high temperature of heat source over 90 ℃ and feed flow rate at 0.6 kg/s are recommended. At 3 g/L of feed concentration, the average permeate flux and net energy density showed 8.04 kg/m²/hr and 2.56 W/m², respectively. The average permeate flux and net energy density were almost constant in the range of feed concentration from 1 to 3 g/L. Compared to the case with seawater feed, the PRMD with brackish water feed showed higher average permeate flux and net energy density. Thus, PRMD application using brackish water feed can be more effective than that using seawater feed in terms of power generation.

• Journal of Soil and Groundwater Environment
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• v.26 no.6
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• pp.95-105
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• 2021

Extensive groundwater abstraction has been recognized as one of the major challenges in management of coastal groundwater. The purpose of this study was to assess potential changes of groundwater distribution of northeastern Jeju Island over 10-year duration, where brackish water have been actively developed. To quantitatively estimate the coastal groundwater resources, numerical simulations using three-dimensional finite-difference density-dependent flow models were performed to describe spatial distribution of the groundwater in the aquifer under various pumping and recharge scenarios. The simulation results showed different spatial distribution of freshwater, brackish, and saline groundwater at varying seawater concentration from 10 to 90%. Volumetric analysis was also performed using three-dimensional concentration distribution of groundwater to calculate the volume of fresh, brackish, and saline groundwater below sea level. Based on the volumetric analysis, a quantitative analysis of future seawater intrusion vulnerability was performed using the volume-based vulnerability index adopted from the existing analytical approaches. The result showed that decrease in recharge can exacerbate vulnerability of coastal groundwater resources by inducing broader saline area as well as increasing brackish water volume of unconfined aquifers.

• Korean Chemical Engineering Research
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• v.55 no.5
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• pp.685-689
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• 2017

We studied the removal of zinc ions from synthetic brackish water by an adsorption method using natural Algerian Bentonite (NAB). The effect of the main physico chemical parameters-contact time, pH, temperature, ionic strength, clay weight and initial metal ion concentrations on the removal of $Zn^{+2}$-were investigated. The results showed that equilibrium was attained within 10 min of stirring time. The retention capacity of $Zn^{+2}$ increased with the increase of pH, the adsorbent dose and ionic strength. A modelization study showed that the adsorption follows Langmuir isotherm, while its kinetics was pseudo-second-order. Based on the results, it was concluded that NAB, which is natural and available, could be used as an alternative for the removal of zinc from saline aqueous solutions.

• Animal Systematics, Evolution and Diversity
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• v.8 no.2
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• pp.325-330
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• 1992

One species and two subspecies of rotifers inhabiting several brackish water lakes on the east coast of Korea are redescribed and illustrated. Keratella cruciformis eichwaldi and Dipleuchlanis propatula propatula are the known species, and Notholca liepetterseni is newly reported from Korea.

• Korean Journal of Environmental Biology
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• v.36 no.3
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• pp.291-298
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• 2018

Samples were collected from benthic and subaerophytic habitats of fresh and brackish water in Korea from April 2017 to April 2018. Accordingly, three genera and seven species were newly recorded in Korea. Three unrecorded genera were Cephalothrix, Cyanophanon and Toxifilum, and seven species were Anagnostidinema pseudacutissimum, Calothrix elenkinii, Cephalothrix komarekiana, Cyanophanon mirabile, Cyanosarcina chroococcoides, Leptolyngbya ectocarpi and Toxifilum mysidocida. Anagnostidinema pseudacutissimum and Cephalothrix komarekiana had been previously reported to inhabit freshwater, but these were found to be present in brackish water during the period of the present study. Also, Cyanosarcina chroococcoides previously reported to inhabit moorland waters and swamps, were found to be present in subaerophytic habitat.

• Korean Journal of Environmental Biology
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• v.36 no.3
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• pp.241-251
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• 2018

To find unrecorded diatom species, random materials were collected from the freshwater, brackish water, and coastal waters. Benthic and periphytic diatoms were sampled from twelve localities. Thirteen species belonging to eight genera are newly added to the national flora of diatom. In the intertidal areas, the five species are new to Korea, Anaulus minutus Grunow, Anaulus simonsenii Witkowski & Metzeltin, Eunotogramma laeve Grunow, Eunotogramma productum Grunow, and Nitzschia subcapitellata Hustedt. The following two species are new from brackish waters, Chamaepinnularia krookiformis (Krammer) Lange-Bertalot & Krammer and Cymatoneis ovalis Heiden. The following four species are new from mountain peatlands, Geissleria ignota (Krasske) Lange-Bertlaot & Metzeltin, Chamaepinnularia hassiaca (Krasske) Cantonati & Lange-Bertalot, Chamaepinnularia mediocris (Krasske) Lange-Bertalot and Pinnularia linearidivergens Kulikovskiy, Lange-Bertalot & Metzeltin. The following two species are new from river or streams, Cymbella hustedtii var. compacta Krammer and Cymbella stigmaphora ${\emptyset}strup$.

• Animal cells and systems
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• v.11 no.2
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• pp.247-253
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• 2007

A new species of Nitokra and Ameira parvula (Claus) belonging to the family Ameiridae are recorded from brackish waters in South Korea. Nitokra koreanus n. sp. most resembles N. spinipes and N. pietschmanni, however, it is characteristic in having the character combination of ellipsoidal P5 exopod and very short P1 enp 1. Ameira parvula is reported for the first time from the Northwestern Pacific. Description of the new species and the taxonomic accounts of both species are presented.

• Korean Journal of Fisheries and Aquatic Sciences
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• v.28 no.1
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• pp.60-66
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• 1995

Vibrio cholerae non-O1 and Vibrio mimicus, food poisoning bacteria, have detected frequently in fresh water and brackish water. To estabilsh prevention measures of food poisoning outbreak by these bacteria, the adaptability and population changes were examined in fresh water, brackish water $(10\%o\;NaCl)$ and seawater $(30\%o\;NaCl)$. Both species poorly survived as temperature increased regardless of water types employed. However, survival time was the shortest in fresh water and longest in seawater at $4^{\circ}C$. In case of brackish water, the bacteria survived best at $15^{\circ}C$ and population were varied only in small numbers. Any significant difference was not observed to both species with respect to water types and temperatures except V. mimicus survived about 5-6 days longer in brackish water. In conclusion, V. cholerae non-O1 and V. mimicus were not likely to be recovered In normal fresh water, brackish water and seawater, and both biological and physicochemical factors could affect survival of these species.

• Korean Journal of Materials Research
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• v.29 no.1
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• pp.16-22
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• 2019

Indirect oxidation using chlorine species oxidizing agents is often effective in wastewater treatment using an electrochemical oxidation process. When chlorine ions are contained in the wastewater, oxidizing agents of various chlorine species are produced during electrolysis. In a ballast water management system, it is also used to treat ballast water by electrolyzing seawater to produce a chlorine species oxidizer. However, ballast water in the brackish zone and some wastewater has a low chlorine ion concentration. Therefore, it is necessary to study the chlorine generation current efficiency at various chlorine concentration conditions. In this study, the chlorine generating current efficiency of a boron-doped diamond(BDD) electrode and insoluble electrodes are compared with various chloride ion concentrations. The results of this study show that the current efficiency of the BDD electrode is better than that of the insoluble electrodes. The chlorine generation current efficiency is better in the order of BDD, MMO(mixed metal oxide), $Ti/RuO_2$, and $Ti/IrO_2$ electrodes. In particular, when the concentration of sodium chloride is 10 g/L or less, the current efficiency of the BDD electrode is excellent.

• Journal of Species Research
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• v.5 no.3
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• pp.514-516
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• 2016

Three marine and one brackish-water ciliates (Dysteria crassipes $Clapar\grave{e}de$ and Lachmann, 1859; Gruberia calkinsi $Beltr\acute{a}n$, 1933; Pleuronema salmastra Dragesco, 1986; Zosterodasys agamaliev Deroux, 1978) were isolated from Incheon in Korea and their morphologies were investigated using live observation and protargol impregnation.