• Journal of Hydrogen and New Energy
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• v.30 no.5
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• pp.436-447
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• 2019

The circulating fluidized bed boiler has an advantage that can burn a variety of fuels from low-grade fuel to coal. In this study, for the design of a circulating fluidized bed boiler using wood pellets, a circulating fluidized bed combustion test device using no external heater was manufactured and used. According to the increase of co-combustion rate with wood pellet, combustion fraction and heat flux by combustor height were measured and pollutant emission characteristics were analyzed. In terms of combustibility, the effect on primary and secondary air ratio were also studied. In addition, as a result of analysis of the effect of corrosive nanoparticles on the combustion of coal with wood pellets, it was confirmed that coal is mostly composed of Ca and S, whereas wood pellets are mostly composed of K, Cl, and Na.

• Proceedings of the Korean Institute of Building Construction Conference
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• 2023.05a
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• pp.297-298
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• 2023

In the concrete industry, efforts are being made to reduce CO₂ emissions, and technologies that collect, store, and utilize CO₂ have recently been studied. This study analyzed the change in compressive strength after the accelerated carbonation test of Non-Sintered Cement(NSC) mortar. Type C Fly Ash and Type F Fly Ash were mixed in a 1:1 ratio and then mixed with Blast Furnace Slag fine powder to produce NSC. The mortar produced was cured underwater until the target age. In addition, an accelerated carbonation test was conducted under the condition of a concentration of 5 (±1.0%) of CO₂ gas for 14 days. The mortar compressive strength was measured before and after 14 days of accelerated carbonation test based on the 7th and 28th days of age. As a result of the experiment, the compressive strength was improved in all binder. In general, the compressive strength of NSC mortar subjected to the accelerated carbonation test was similar to that of Ordinary Portland Cement(OPC) mortar not subjected to the accelerated carbonation test.

• Journal of Environmental Science International
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• v.29 no.11
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• pp.1055-1064
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• 2020

In this research, heavy metals and T-P removal characteristics of plated wastewater are derived using BPC(Break Point Chlorination) process. AA sedimentation pond outflow(Influence) was evaluated for the removal efficiency of heavy metal(Ni) and T-P at a reaction time of 25 minutes by NaOCl input volume(9, 11, 13 and 15 mL). In the case, the higher the NaOCl input volumes, the higher the ORP values were maintained and the higher the removal efficiency tended to be. On the other hand, T-P was judged to have a low relationship between the ORP value and the removal efficiency. In addition, the efficiency of removal heavy metals and T-P in the plated wastewater by injecting 10 mL, 15 mL, 20 mL and 25 mL NaOCl, increased as the amount of NaOCl injected increased, the amount of NaOH input for pH increased. It was found that suspended solid in effluence also increased. It was also observed that the color of the plating wastewater changed from yellowish green to green to charcoal gray to black as the amount of NaOCl injected increased. Treatment characteristics of the reaction time, the longer the reaction time with the substance to be treated after the input of NaOCl, the more the heavy metal removal efficiency tended to increase. Through XRF analysis of the sludge, the constituents in the sludge such as NaCNO, CNCl, Na₃PO₄, CrO₄, 2Na₂CrO₄ and 2NaNO₃ will be analyzed in detail, and the mechanisms of the reaction between the plated wastewater and the complex compound will be elucidated.

• Journal of the Society of Cosmetic Scientists of Korea
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• v.42 no.3
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• pp.247-255
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• 2016

In order to select a strain that forms a Biocellulose (BC), strain producing acetic acid was selected from commercially available kombucha. Through SM broth it was confirmed that the strain is a gram negative bacteria in the form of rods having no motility through a phase contrast microscope. The result of phylogenetic inference analysis based on 16S rDNA sequence analysis for the identification of strains was most closely related to Gluconobacter uchimurae (G. uchimurae) and was named G. uchimurae GYS15 strain. The strain showed the highest degree of growth when cultured for 14 days under the conditions of pH 5 and $25^{\circ}C$. Moreover, it showed the highest degree of growth in a Glucose addition disaccharide as the optimum carbon source sucrose and fructose. Also, 0.5% NaCl, upon the addition of Malto extract, showed the highest degree of growth. Based on investigation by the optimum growth conditions to confirm the physical properties of BC obtained by culturing G. uchimurae GYS15 strains. The surface structure was observed through an scanning electron microscope (SEM) showed a high networks structure. It until $8.6{\pm}0.38$ times when the water holding capacity is re-absorbed and re-absorbed holding oil up to $6.6{\pm}0.51$ times confirmed. In conclusion, using these material properties, it was possible to confirm the possibility of a variety of cosmetic materials and mask pack materials.

• Journal of Hydrogen and New Energy
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• v.18 no.3
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• pp.284-291
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• 2007

The Ni-MH batteries for HEV and industry are normally placed in outdoor, consequently causing an too weak discharge power problem due to a cold weather specially in winter time. In order to improve the low temperature performances of the Ni-MH battery for HEV and industrial uses, it has been investigated the low temperature discharge characteristics of Ni-MH battery with various electrolytes at $-18^{\circ}C$. The summary of experimental results are as follows. The low temperature characteristics depended strongly on the characteristics of electrolytes. When the concentration of the electrolytes were too high or too low the low temperature performance was poor. The best electrolyte was composed of KOH 6.2M+LiOH 1.2M. An addition of RbOH or CsOH to electrolyte improved the low temperature performance. The best total concentration of electrolyte composed of KOH, NaOH and LiOH was about 7M.

• Journal of the Korean Society for Library and Information Science
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• v.56 no.4
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• pp.181-203
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• 2022

This study analyzed domestic and foreign literature and examined cases of foreign Community of Practice(CoP) of experts to find out what benefits researchers can gain from participating in their CoP, how the CoP was established, and how data is shared within the CoP. In addition, this study discussed on how to establish a CoP of experts in Korea for sharing and using research data. By participating in the CoP of experts, members can be provided with the opportunity to build an experts' network and have a chance to meet with various experts, to acquire and share their expertise and information, to receive help from other experts, to learn about their expertise, and to have opportunities for professional experiences. In addition, this study discussed 4 factors such as operation method and management system, memberships and number of members, activities, and management of data and repository for establishing a CoP of experts for sharing and using research data. This study provides a knowledge base for building a CoP of experts in Korea.

• BMB Reports
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• v.31 no.5
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• pp.453-458
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• 1998

Human thrombopoietin (hTPO) was expressed to high levels in insect cells using the baculovirus expression system. Full-length hTPO cDNA containing a native signal peptide sequence was amplified by PCR from a human fetal liver cDNA library and cloned into the Autographa californica nuclear polyhedrosis virus (AcNPV) expression vector. Immunoblot analysis with antiserum against hTPO indicated that an approximately 55 kDa protein was produced in recombinant AcNPV infected insect cells. Recombinant hTPO was produced 4-fold higher in Trichoplusia ni (Tn5) cells than in Spodoptera frugiperda (Sf9) cells. with most of the hTPO produced in Tn5 cells secreted into the culture medium. Addition of tunicamycin in the culture medium resulted in the reduction of the size of hTPO to 35-38 kDa, and most of the protein remained within the cell. These results suggest that N-glycosylation of hTPO is required for the secretion of the protein into the culture medium in insect cells. hTPO produced in insect cells induced proliferation and maturation of megakaryocyte progenitors, indicating that it is in a biologically active form.

• International Journal of Oral Biology
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• v.30 no.1
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• pp.23-30
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• 2005

Bone remodeling is a process controlled by the action of two major bone cells; the bone forming osteoblast and the bone resorbing osteoclast. In the process of osteoclastogenesis, stromal cells and osteoblast produce RANKL, OPG, and M-CSF, which in turn regulate the osteoclastogenesis. During the bone resorption by activated osteoclasts, extracellular $Ca^{2+}/{PO_4}^{2-}$ concentration and degraded organic materials goes up, providing the hypertonic microenvironment. In this study, we tested the effects of hypertonicity due to the degraded organic materials on osteoclastogenesis in co-culture system. It was examined the cellular response of osteoblastic cell in terms of osteoclastogenesis by applying the sucrose, and mannitol, as a substitute of degraded organic materials to co-culture system. Apart from the sucrose, mannitol, and NaCl was tested to be compared to the effect of organic osmotic particles. The addition of sucrose and mannitol (25, 50, 100, 150, or 200 mM) to co-culture medium inhibited the number of tartrate-resistant acid phosphatase (TRAP) positive multinucleated cells induced by 10 nM $1{\alpha},25(OH)_2vitaminD_3$ ($1{\alpha},25(OH)_2D_3$). However, NaCl did exert harmful effect upon the cells in this co-culture system, which is attributed to DNA damage in high concentration of NaCl. To further investigate the mechanism by which hypertonicity inhibits $1{\alpha},25(OH)_2D_3$-induced osteoclastogenesis, the mRNA expressions of receptor activator of nuclear factor (NF)-kB ligand (RANKL) and osteoprotegerin (OPG) were monitored by RT-PCR. In the presence of sucrose (50 mM), RANKL mRNA expression was decreased in a dose-dependent manner, while the change in OPG and M-CSF mRNA were not occurred in significantly. The RANKL mRNA expression was inhibited for 48 hours in the presence of sucrose (50 mM), but such a decrement recovered after 72 hours. However, there were no considerable changes in the expression of OPG and M-CSF mRNA. Conclusively, these findings strongly suggest that hypertonic stress down-regulates $1{\alpha},25(OH)_2D_3$-induced osteoclastogenesis via RANKL signal pathway in osteoblastic cell, and may playa pivotal role as a regulator that modulates osteoclastogenesis.

• Journal of the Korea Organic Resources Recycling Association
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• v.9 no.2
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• pp.93-100
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• 2001

To study the possibility of agricultural utilization of seafood processing wastewater sludges, the change of temperature, decreasing ratio of weight generation quantity of $CO_2$ and $NH_3$, and contents of inorganic elements for composting by adding different rates of zeolite and livestock manure to seafood processing wastewater sludges were investigated. Changes of temperature, decreasing ratio of total weight and generation quantity of $CO_2$ were not little different with increasing addition rates of zeolite for composting. But the less addition quantity of livestock manure is, the higher were temperature and decreasing ratio weight for composting. Ceneration quantity of $NH_3$ in composting materials as adding zeolite ti 5, 10 and 20% and livestock manure to 50, 65 and 80% were 68, 61 and $46mg/kgvs{\cdot}hr$, respectively, for composting periods. So, $NH_3$ generated little quantity as much as possible addition of zeolite and manure. Contents of T-C and T-N little decreased and C/N ratio little increased after composting than before. Content of $P_2O_5$, $K_2O$, CaO also increased a little, that of MgO is not different and that of Mn decreased very sharply in all conditions after composting than before.

• Applied Chemistry for Engineering
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• v.22 no.5
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• pp.526-531
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• 2011

The present study attempted to impregnate alkali metals to amino acid in order to improve $CO_2$ absorption capacity. A used amino acid was glycine, of which pH increased up to about 11 with the addition of alkalies. $CO_2$ absorption capacity of amino acid salts was evaluated in a batch and a continuous process. The absorption capacity appeared in turns as; Sodium Glycinate ${\geq}$ Lithium Glycinate > Potassium Glycinate. Amino acid salts showed lower absolute capacity of $CO_2$ absorption than primary amine (Monoethanolamine) at $20^{\circ}C$. In a continuous absorption with 10% $CO_2$ flow, the increasing the reaction temperature, the increasing rate of absorption for amino and was higher that of than amino absorbent.