• Journal of Environmental Science International
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• v.25 no.11
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• pp.1541-1554
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• 2016

To understand the characteristics of vanadium leaching from soils formed by the weathering of basalts, paleo soil at Gosan, Jeju Island, Korea, and several present-day soils from neighboring areas were collected. Leaching experiments were carried out by two approaches: 1) batch experiments under various geochemical conditions (redox potential (Eh) and pH) and 2) continuous leaching experiments under conditions similar to those of natural environments. From the batch experiments, leached vanadium concentrations were highest under alkaline (NaOH) conditions, with a maximum value of $2,870{\mu}g/L$, and were meaningful (maximum value, $114{\mu}g/L$) under oxidizing ($H_2O_2$) conditions, whereas concentrations under other conditions (acidic-HCl, $neutral-NaHCO_3$, and $reducing-Na_2S_2O_3$) were negligible. This indicated that the geochemical conditions, in which soil-water reactions occurred to form groundwater with high vanadium concentrations, were under alkaline-oxidizing conditions. From the continuous leaching experiments, the pH and leached vanadium concentrations of the solution were in the ranges of 5.45~5.58 and $6{\sim}9{\mu}g/L$, respectively, under $CO_2$ supersaturation conditions for the first 15 days, whereas values under $O_2$ aeration conditions after the next 15 days increased to 8.48~8.62 and $9.7{\sim}12.2{\mu}g/L$, respectively. Vanadium concentrations from the latter continuous leaching experiments were similar to the average concentration of groundwater in Jeju Island ($11.2{\mu}g/L$). Furthermore leached vanadium concentrations in continuous leaching experiments were highly correlated with pH and Al, Cr, Fe, Mn and Zn concentrations. The results of this study showed that 1) alkaline-oxidizing conditions of water-rock (soil) interactions were essential to form vanadium-rich groundwater and 2) volcanic soils can be a potential source of vanadium in Jeju Island groundwater.

• Korean Journal of Psychosomatic Medicine
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• v.27 no.2
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• pp.77-84
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• 2019

Objectives : The Illness Intrusiveness Rating Scale (IIRS) is a well-validated self-report instrument for assessing negative impact of chronic illness and/or adverse effects of its treatment on everyday life domains. Although extensive literature probed its psychometric properties in medical illness, little attention was paid for its validity for psychiatric population. This study aimed to test factorial structure of the Korean Version of the IIRS (IIRS-K) in a consecutive sample of psychiatric outpatients. Methods : Data set of 307 first-visit patients of psychiatric clinic at Guri Hanyang univ. Hospital were used. Exploratory and confirmatory factor analysis, internal consistency were tested in IIRS-K. We also checked Spearman's correlation analysis between IIRS-K, Zung's self-report anxiety scale and Zung's self-report depression scale. Results : 76.9% of the patients were with anxiety disorder and depressive disorder. The principal component factor analysis of the IIRS-K extracted three-factor structure accounted for 63.2% of total variance that was contextually similar to the original English version. This three-factor solution showed the best fit when tested confirmatory factor analysis compared to the original IIRS, two-factor model of IIRS-K suggested from medical outpatients, and one-factor solution. The IIRS-K also showed good internal consistency (Cronbach's α=0.90) and good convergent validity with anxiety and depression scales. Conclusions : The IIRS-K showed the three-factor structure that was similar but not identical to original version. Overall, this study proved factorial validity of the IIRS-K and it can be used for Korean clinical population.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.362-362
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• 2017

Dissemination of IPB3S rice variety combined with cultivation technology named IPB Prima was aimed to introduce IPB research product particularly for IPB rice variety with high-yield character that is IPB3S. The rice variety IPB3S and IPB Prima cultivation technology was expected to be one of solution to improve rice productivity and accelerate to food self-sufficiency in Indonesia. Research sctivity was consist of three main research unit i.e. (1) Dissemination of IPB3S rice variety and IPB Prima production technology; (2) The development of Information and management web-based system (IMS) for planning and monitoring IPB3S and IPB Prima application distribution; and (3) The development of High-capacity grain drying system in Fluidized-bed drying ang in-store drying system. The objective of main research i.e. to introduce IPB high-yield rice variety, to accelerate rice productivity to support self-sufficiency, to develop integrated system model through fluidized and in-store drying, and to develop web-based management-information system in result analyzing IPB3S and IPB Prima distribution and technology application. The dissemination activities was arranged in two location. The first location was in Banyuwangi, East Java with total area 10.87 ha, consist of 8.91 ha planting area for IPB3S and 1.96 ha planting area for Ciherang. The second location is in Tegal, Middle Java with total planting area in 5 ha. The experiment was arranged in different treatment of varieties and cultivation method. The experiment consist of (1) rice variety Ciherang with conventional cultivation technology (P0); (2) rice variety Ciherang with IPB Prima cultivation technology (P1); (3) rice variety IPB3S with conventional cultivation technology (P2); (4) rice variety IPB3S with IPB Prima cultivation technology (P3). Planting distance for twin rows system is $50cm{\times}25cm{\times}12.5cm$. Planting distance for single row system is $25cm{\times}25cm$. The research result elucidated that productivity result in two location has different grades in similar trend. Experiment in Tegal resulted P0 result is $6.18ton\;ha^{-1}$, P1 result is $6.30ton\;ha^{-1}$, P2 result is $6.82ton\;ha^{-1}$, P3 result is $7.31ton\;ha^{-1}$. Experiment in Banyuwangi resulted optimum production of IPB3S variety productivity number are $7.29ton\;ha^{-1}$, while Ciherang are $6.73ton\;ha^{-1}$.

• Proceedings of the Korean Society of Crop Science Conference
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• 2017.06a
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• pp.61-61
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• 2017

Dissemination of IPB3S rice variety combined with cultivation technology named IPB Prima was aimed to introduce IPB research product particularly for IPB rice variety with high-yield character that is IPB3S. The rice variety IPB3S and IPB Prima cultivation technology was expected to be one of solution to improve rice productivity and accelerate to food self-sufficiency in Indonesia. Research sctivity was consist of three main research unit i.e. (1) Dissemination of IPB3S rice variety and IPB Prima production technology; (2) The development of Information and management web-based system (IMS) for planning and monitoring IPB3S and IPB Prima application distribution; and (3) The development of High-capacity grain drying system in Fluidized-bed drying ang in-store drying system. The objective of main research i.e. to introduce IPB high-yield rice variety, to accelerate rice productivity to support self-sufficiency, to develop integrated system model through fluidized and in-store drying, and to develop web-based management-information system in result analyzing IPB3S and IPB Prima distribution and technology application. The dissemination activities was arranged in two location. The first location was in Banyuwangi, East Java with total area 10.87 ha, consist of 8.91 ha planting area for IPB3S and 1.96 ha planting area for Ciherang. The second location is in Tegal, Middle Java with total planting area in 5 ha. The experiment was arranged in different treatment of varieties and cultivation method. The experiment consist of (1) rice variety Ciherang with conventional cultivation technology (P0); (2) rice variety Ciherang with IPB Prima cultivation technology (P1); (3) rice variety IPB3S with conventional cultivation technology (P2); (4) rice variety IPB3S with IPB Prima cultivation technology (P3). Planting distance for twin rows system is $50cm{\times}25cm{\times}12.5cm$. Planting distance for single row system is $25cm{\times}25{\times}cm$. The research result elucidated that productivity result in two location has different grades in similar trend. Experiment in Tegal resulted P0 result is $6.18ton\;ha^{-1}$, P1 result is $630ton\;ha^{-1}$, P2 result is $6.82ton\;ha^{-1}$, P3 result is $7.31ton\;ha^{-1}$. Experiment in Banyuwangi resulted optimum production of IPB3S variety productivity number are 7.29 ton ha-1, while Ciherang are $6.73ton\;ha^{-1}$.

• Proceedings of the Korean Vacuum Society Conference
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• 2016.02a
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• pp.102-102
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• 2016

Water, which is most abundant in Earth surface and very closely related to all forms of living organisms, has a simple molecular structure but exhibits very unique physical and chemical properties. Even though tremendous effort has been paid to understand this nature's core substance, there amazingly still lefts much room for scientist to explore its novel behaviors. Especially, as the scale goes down to nano-regime, water shows extraordinary properties that are not observable in bulk state. One of such interesting features is the formation of nanoscale bubbles showing unusual long-term stability. Nanobubbles can be spontaneously formed in water on hydrophobic surface or by decompression of gas-saturated liquid. In addition, the nanobubbles can be generated during electrochemical reaction at normal hydrogen electrode (NHE), which possibly distorts the standard reduction potential at NHE as the surface nanobubble screens the reaction with electrolyte solution. However, the real-time evolution of these nanobubbles has been hardly studied owing to the lack of proper imaging tools in liquid phase at nanoscale. Here we demonstrate, for the first time, that the behaviors of nanobubbles can be visualized by in situ transmission electron microscope (TEM), utilizing graphene as liquid cell membrane. The results indicate that there is a critical radius that determines the long-term stability of nanobubbles. In addition, we find two different pathways of nanobubble growth: i) Ostwald ripening of large and small nanobubbles and ii) coalescence of similar-sized nanobubbles. We also observe that the nucleation and growth of nanoparticles and the self-assembly of biomolecules are catalyzed at the nanobubble interface. Our finding is expected to provide a deeper insight to understand unusual chemical, biological and environmental phenomena where nanoscale gas-state is involved.

• Korean Chemical Engineering Research
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• v.46 no.3
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• pp.443-450
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• 2008

Efficient use of low rank coals (LRC) have been investigated as a method to cope with recent high oil price. Among the coals used in industry, lignite and sub-bituminous coals are belong to the LRC, and have abundant deposit and are distributed worldwide, but high moisture contents and self ignition properties inhibits their utilization. In this paper, chemical coal cleaning to produce ash-free coal from LRC has been investigated. Two technologies, that is, UCC(Ultra Clean Coal) process removing ash from coal and Hyper Coal process extracting combustibles from coal were compared with. UCC process has merits of simple and reliable when it compared with Hyper Coal process, but the remaining ash contents werehigher than Hyper Coal. Hyper Coal has ash contents under the 200ppm when raw coal is treated with appropriate solvent and ion exchange materials to remove alkali materials in extracted solution. The ash-free coal which is similar grade with oil can be used as alternate oil in the industry, and also used as a high grade fuel for IGCC, IGFC and other advanced combustion technology.

• Korean Journal of Food Science and Technology
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• v.35 no.3
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• pp.410-416
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• 2003

Effects of calcium and chitosan treatments on storage and quality of pork were investigated. Porks were coated with 1% each of 30 and 120 kDa chitosans in 3% gelatin solution. Self-life and antioxidation increased significantly in all samples. In contrast with non-treated group, pH of the chitosan-treated group was very stable. Moisture content and water activity (Aw) were similar among all samples. Water-holding capacity decreased slightly, whereas cooking loss increased, during storage in all samples. Value of redness increased in chitosan-coated pork. Tenderness of pork injected with calcium was the highest among all samples. These results showed that preservation and quality of pork were improved by the treatment of calcium and 30 kDa of chitosan.

• Journal of the Korean Chemical Society
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• v.51 no.6
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• pp.526-535
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• 2007

Ru(II)-terpyridine complexes (8, 9, 11) linked with adamantyl or β-cyclodextrin moieties were synthesized and characterized based on their 1H and 13C NMR spectra as well as MS spectra. Ru(II)-terpyridine complexes (8, 11) linked with adamantyl moiety were readily dissolved in aqueous solution via encapsulation by β-cyclodextrin when they were mixed with an equimolar amount of β-cyclodextrin. In the similar way, the adamantane guest of the Ru(II)-terpyridine complexes (8, 11) were encapsulated by β-cyclodextrin moiety of the ruthenium complex 9 to afford supramolecular assemblies in aqueous environment. Formation of assemblies was corroborated by 1H NMR spectroscopy.

• Journal of Powder Materials
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• v.17 no.3
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• pp.216-222
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• 2010

Self-standing $TiO_2$ nanotube arrays were fabricated by potentiostatic anodic oxidation method using pure Ti foil as a working electrode and ethylene glycol solution as electrolytes with small addition of $NH_4F$ and $H_2O$. The influences of anodization temperature and time on the morphology and formation of $TiO_2$ nanotube arrays were investigated. The fabricated $TiO_2$ nanotube arrays were applied as a photoelectrode to dye-sensitized solar cells. Regardless of anodizing temperature and time, the average diameter and wall thickness of $TiO_2$ nanotube show a similar value, whereas the thickness show a different trend with reaction temperature. The thickness of $TiO_2$ nanotube arrays anodized at $20^{\circ}C$ and $30^{\circ}C$ was time-dependent, but on the other hand its at $10^{\circ}C$ are independent of anodization time. The conversion efficiency is low, which is due to a morphology breaking of the $TiO_2$ nanotube arrays in manufacturing process of photoelectrode.

• Journal of the korean society of oceanography
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• v.31 no.2
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• pp.75-88
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• 1996

The analytic and numerical solution of the 1$\frac{1}{2}$-layer and 2$\frac{1}{2}$-layer models are derived. The large coastal-sea level drop and the fast westward speed of the anticyclonic gyre due to strong offshore winds using two ocean models are investigated. The models are forced by wind stress fields similar in structure to the intense mountain-pass jets(${\sim}$20 dyne/$cm^{2}$) that appear in the Gulfs of Tehuantepec and Papagayo in the Central America for periods of 3${\sim}$7 days. Analytic and numerical solutions compare favorably with observations, the large sea-level drop (${\sim}$30 cm) at the coast and the fast westward propagation speeds (${\sim}$13 km/day) of the gyres. The coastal sea-level drop is enhanced by several factors: horizontal mixing, enhanced forcing, coastal geometry, and the existence of a second active layer in the 2$\frac{1}{2}$-layer model. Horizontal mixing enhances the sea-level drop because the coastal boundary layer is actually narrower with mixing. The forcing ${\tau}$/h is enhanced near the coast where h is thin. Especially, in analytic solutions to the 2$\frac{1}{2}$-layer model the presence of two baroclinic modes increases the sea-level drop to some degree. Of theses factors the strengthened forcing ${\tau}$/h has the largest effect on the magnitude of the drop, and when all of them are included the resulting maximum drop is -30.0 cm, close to observed values. To investigate the processes that influence the propagation speeds of anticyclonic gyre, several test wind-forced calculations were carried out. Solutions to dynamically simpler versions of the 1$\frac{1}{2}$-layer model show that the speed is increased both by ${\beta}$-induced self-advection and by larger h at the center ofthe gyres. Solutions to the 2$\frac{1}{2}$-layer model indicate that the lower-layer flow field advects the gyre westward and southward, significantly increasing their propagation speed. The Papagayo gyre propagates westward at a speed of 12.8 km/day, close to observed speeds.