• Korean Journal of Soil Science and Fertilizer
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• v.45 no.5
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• pp.717-724
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• 2012

Salt accumulated soil should be reclaimed to lower salt level for crop production. This study was carried out to investigate the characteristics of water flow and transport of mono and divalent solutes on salt accumulated soils with different head pressures. Saturated hydraulic conductivity was measured by constant and falling head methods with maintaining different head pressures. Saturated hydraulic conductivity was influenced by bulk density and organic matter contents in soils, but it had different elusion patterns between saline and sodic soil. While the quantity of water necessary for reclamation could be varies with soil type, it was considered that the supply of one pore volume of water was affordable and economic. Additional head pressure significantly increased the volume of leachate at a given time and it was more effective at low organic matter soils. The results indicate that additional head pressure would be one of the best irrigation practices on desalination method for salt accumulated soils.

• Proceedings of the Membrane Society of Korea Conference
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• 2004.05a
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• pp.109-112
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• 2004

The charged mosaic membranes having cation and anion exchange mixed groups within membrane were researched. The composite charged mosaic membrane was investigated from simultaneous transport such as solute and solvent flux. On the other hand, the reflection coefficient and salt flux coefficient were estimated by taking account of the cross constants of the phenomenological equation.(omitted)

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.18 no.4
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• pp.421-437
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• 2020

This study provides an assessment on a proposed method for separation of cesium, strontium, and barium using electrochemical reduction at a liquid bismuth cathode in LiCl-KCl eutectic salt, investigated via cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS), and scanning electron microscopy with energy dispersive X-ray spectrometry (SEM-EDS). CV studies were performed at temperatures of 723-823 K and concentrations of the target species up to 4.0wt%. Redox reactions occurring during potential sweeps were observed. Concentration of BaCl2 in the salt did not seem to influence the diffusivity in the studied concentration range up to 4.0wt%. The presence of strontium in the system affected the redox reaction of lithium; however, there were no distinguishable redox peaks that could be measured. Impedance spectra obtained from EIS methods were used to calculate the exchange current densities of the electroactive active redox couple at the bismuth cathode. Results show the rate-controlling step in deposition to be the mass transport of Cs+ ions from the bulk salt to the cathode surface layer. Results from SEM-EDS suggest that Cs-Bi and Sr-Bi intermetallics from LiCl-KCl salt are not thermodynamically favorable.

• Journal of Microbiology and Biotechnology
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• v.19 no.5
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• pp.447-454
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• 2009

The transport of spermidine into a cyanobacterium, Synechocystis sp. pec 6803, was characterized by measuring the uptake of $^{14}C$-spermidine. Spermidine transport was shown to be saturable with an apparent affinity constant ($K_m$) value of $67{\mu}M$ and a maximal velocity ($V_{max}$) value of 0.45 nmol/min/mg protein. Spermidine uptake was pH-dependent with the pH optimum being 8.0. The competition experiment showed strong inhibition of spermidine uptake by putrescine and spermine, whereas amino acids were hardly inhibitory. The inhibition kinetics of spermidine transport by putrescine and spermine was found to be noncompetitive with $K_i$ values of 292 and $432{\mu}M$, respectively. The inhibition of spermidine transport by various metabolic inhibitors and ionophores suggests that spermidine uptake is energy-dependent. The diminution of cell growth was observed in cells grown at a high concentration of NaCl. Addition of a low concentration of spermidine at 0.5 mM relieved growth inhibition by salt stress. Upshift of the external osmolality generated by either NaCl or sorbitol caused an increased spermidine transport with about 30-40% increase at 10 mosmol/kg upshift.

• Proceedings of the Membrane Society of Korea Conference
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• 2005.11a
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• pp.96-101
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• 2005

A theory for the material transports through ion exchange membrane has been developed on the basis of nonequilibrium thermodynamics by removing the assumption of solvent flow in the previous paper and applied to a detailed study of the ionic transport properties of new charged mosaic membrane(CMM) system. The CMM having two different fixed charges in the polymer membrane indicated unique selective transport behavior then ion-exchange membrane. The separation behavior of ion transport across the CMM with a parallel array of positive and negative functional charges were investigated. It was well-known the analysis of the volume flux and solute flux based on nonequilibrium thermodynamics. Our suggests preferential salt transport across the charged mosaic membranes. Transport properties of heavy metal ions, $Mg^{2+}$, $Mn^{2+}$and sucrose system across the charged mosaic membrane were estimated. As a result, we were known metal salts transport depended largely on the CMM. The reflection coefficient indicated the negative value that suggested preferential material transport and was independent of charged mosaic membrane thickness.

• Journal of Advanced Marine Engineering and Technology
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• v.40 no.6
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• pp.458-467
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• 2016

Salt is the most important substance in physiological activities of the human body concerning transport of the ingested nutrients into the blood. Thus, the most ideal salt must not contain any harmful ingredients such as cadmium, mercury, lead, and arsenic. However, it is legal to include trace amounts of the hazardous ingredients in salt owing to a technical limitation, because salt is generally obtained from seawater. This paper reported an experimental result about a new method of manufacturing high-quality table salts without hazardous ingredients by using "$15^{\circ}C$ low-temperature vacuum drying technology," applied to the sequential extraction phenomenon of seawater with increasing the concentration. The world's best table salt can be produced if the present results are applied and extended to the traditional solar salt industry.

• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.307-307
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• 2006

The reduction behavior of silver ions to silver nanoparticles is an important research topic in polymer/silver salt complex membranes for facilitated olefin transport, because it has a significant effect on the long-term stability of membrane performance. In this study, the effects of solvent on the formation of silver nanoparticles and long-term membrane performance in polymer/silver salt complex membrane were investigated. This effect was assessed for the complexes of poly(N-vinyl pyrrolidone) $(PVP)/AgBF_{4}$ with the use of ionic liquid (IL), acetonitrile (ACN) and water as a solvent. Membrane performance test shows that long-term stability is strongly dependent on the kind of solvent and arranged: IL > ACN >> water.

• The Korean Journal of Physiology and Pharmacology
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• v.2 no.5
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• pp.541-547
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• 1998

• KOREAN JOURNAL OF CROP SCIENCE
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• v.67 no.1
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• pp.41-52
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• 2022

As a cultivar of Korean wheat, 'Keumgang' wheat variety has a fast growth period and can be grown stably. Hexaploid wheat (Triticum aestivum) has moderately high salt tolerance compared to tetraploid wheat (Triticum turgidum L.). However, the molecular mechanisms related to salt tolerance of hexaploid wheat have not been elucidated yet. In this study, the candidate genes related to salt tolerance were identified by investigating the genes that are differently expressed in Keumgang variety and examining salt tolerant mutation '2020-s1340.'. A total of 85,771,537 reads were obtained after quality filtering using NextSeq 500 Illumina sequencing technology. A total of 23,634,438 reads were aligned with the NCBI Campala Lr22a pseudomolecule v5 reference genome (Triticum aestivum). A total of 282 differentially expressed genes (DEGs) were identified in the two Triticum aestivum materials. These DEGs have functions, including salt tolerance related traits such as 'wall-associated receptor kinase-like 8', 'cytochrome P450', '6-phosphofructokinase 2'. In addition, the identified DEGs were classified into three categories, including biological process, molecular function, cellular component using gene ontology analysis. These DEGs were enriched significantly for terms such as the 'copper ion transport', 'oxidation-reduction process', 'alternative oxidase activity'. These results, which were obtained using RNA-seq analysis, will improve our understanding of salt tolerance of wheat. Moreover, this study will be a useful resource for breeding wheat varieties with improved salt tolerance using molecular breeding technology.

• Transactions of the Korean Society of Mechanical Engineers B
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• v.34 no.12
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• pp.1093-1099
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• 2010

For Very High Temperature Reactors (VHTR), the designs of the Intermediate Heat Transport Loop (IHTL) and the Intermediate Heat Exchanger (IHX) are particularly difficult because of the high-temperature operation (up to $950^{\circ}C$). In this study, Flinak molten salt, a eutectic mixture of LiF, NaF, and KF (46.5:11.5:42.0 mole %) is considered as the heat transporting fluid in the IHTL. To evaluate the flow and heat transfer performance of the Flinak molten salt in small channels with hydraulic diameters in the millimeter range, a double-pipe heat exchanger was constructed using small-diameter tubes for the heat exchange between the Flinak and the gas flow. The experimental data showed that, for laminar Flinak flow, the measured friction factors were close to the 64/Re curve and the Nusselt numbers were generally between 3.66 and 4.36.