• Journal of Plant Biotechnology
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• v.36 no.4
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• pp.373-383
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• 2009

To set efficient transformation system in chrysanthemum, thirty-four chrysanthemum (Dendranthema grandiflorum Kitamura) varieties were collected and cultured for shoot regeneration. Five varieties, ‘Shuho-no-chikara', ‘Zinba', ‘Baekma', ‘Pink pride' and ‘Keumsu' of them were selected, because they had a high shoot regeneration efficiency. MS medium containing 1.0 mg/L NAA and BA respectively was very adequate for shoot regeneration in those varieties. MS medium with 3.0 mg/L NAA and 1.0 mg/L kinetin in ‘Shuho-no-chikara' and the medium with 0.5 mg/L NAA and 3.0 mg/L BA in ‘Keumsu' were also suitable for shoot regeneration. The most efficient callus induction and shoot regeneration were obtained on MS medium. Shoot regeneration was enhanced more than 8% on MS medium with 0.3% phytagel and 10-15 mg/L putrescine. The best cultural material for shoot regeneration was stem. When stem was used as a culture material, shoot regeneration rate was increased more than 26% and the days to shoot regeneration was shortened about 14 days.

• Journal of Korean Society of Environmental Engineers
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• v.22 no.2
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• pp.291-302
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• 2000

This experiments have been made to develop of manganese-based sorbent for the removal of hydrogen sulfide from hot coal gases. Manganese-based sorbent were tested in an ambient-pressure fixed-bed reactor to determine steady state $H_2S$ concentrations, breakthrough times and feasibility of the sorbent when subjected to cycle sulfidation and regeneration testing. Effects of particle size of sorbent, temperature of sulfidation, regeneration temperature and regeneration characteristics on the $H_2S$ removal efficiency were investigated. Experimental results showed that the $H_2S$ removal efficiency was optimal when the temperature was about $800^{\circ}C$ and the smaller particle size, the better $H_2S$ removal efficiency but in the range of 0.214~0.631mm didn't influence it much. The equilibrium constant(K) is represented as a log(K)=3.396/T-1.1105 and the utilization efficiency of sorbents was about 92% at $800^{\circ}C$. Regeneration in air produced $SO_2$ concentration as high as 8.5% at $800^{\circ}C$, 8.4% at $850^{\circ}C$, and 8.8% at $900^{\circ}C$ and may be used in sulfuric acid production.

• Journal of Korean Society for Atmospheric Environment
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• v.23 no.5
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• pp.539-546
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• 2007

Increasing emission of $CO_2$ significantly effects the global warming. Chemical absorption is one of separation methods of $CO_2$ from the industrial flue gases. In this study, the $CO_2$ removal efficiency as well as the $CO_2$ absorption amount of aqueous AMP (2-amino-2-methyl-1-propanol) solutions were measured using the continuous absorption and regeneration apparatus. We investigated the effect of aqueous AMP+AEPD(2-amino-2-ethyl-1, 3-propanediol) and AMP+TIPA (triisopropanolamine) solutions to enhance absorption characteristics of AMP. As a result of this study, the absorption amount and $CO_2$ removal efficiency were increased with adding TIPA into 30 wt.% AMP. The absorption amount and $CO_2$ removal efficiency of aqueous 30 wt.% AMP+5 wt.% TIPA solution were $1.70\;kg-CO_2/kg-absorbent$ and 91.1%, while those of aqueous 30 wt.% AMP solution were $1.58\;kg-CO_2/kg-absorbent$ and 89.3%. In addition, aqueous 30 wt.% AMP+5 wt.% TIPA solution used in the study revealed the high stripping efficiency, which was almost 98%, at the temperature of $110^{\circ}C$. Thus, the temperature of regenerator should be operated at $110^{\circ}C$.

• Journal of the Korea Organic Resources Recycling Association
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• v.21 no.4
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• pp.82-87
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• 2013

A study on desorption and regeneration characteristics for silver ions adsorbed onto crab shells was carried out by means of Nitric acid soultion which was selected as the best desorbing agent. Desorption efficiency for silver ions was the highest as about 96% at the 1.0M of Nitric acid concentration. Also, silver ions was almost desorbed below 1.0 of S/L(mg/mL) ratio which is defined as the ratio of adding amount of adsorbent and volume of desorbing agent and most of desorption process was completed within 60min. And removal efficiency of reused crab shells for silver ions was maintained as about 92% until the 2nd cycle.

• Korean Chemical Engineering Research
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• v.43 no.3
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• pp.432-437
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• 2005

An electric swing adsorption (ESA) process for recovering highly pure $CO_2$ from the mixed gases was tested. In this study, activated carbon fibers were used as an adsorbent. The activated carbon fibers showed fast adsorption rate and the high adsorption capacity for $CO_2$ adsorption under the condition of the ambient pressure. Activated carbon fiber with higher specific surface area was suitable to repeated adsorption-desorption cycle process, showing consistent breakthrough curve. Especially, the regeneration method by vacuum combined with ESA improved the performance of desorption process by an additional 17％ regeneration efficiency compared to a vacuum only method, and showed the high regeneration efficiency at comparatively low 7-8 Wh energy.

• Transactions of the Korean Society of Automotive Engineers
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• v.14 no.4
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• pp.68-76
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• 2006

The minimization of maximum DPF wall temperature and the fast Light-off during regeneration are the targets for the high durability of the DPF system and the high efficiency of regeneration. In order to predict transient thermal response of DPF, one-channel numerical modeling has been adopted. The effect of the ratio of length to diameter(L/D), cell density, the amount of soot loading on temporal thermal response and regeneration characteristics has been numerically investigated under two different running conditions: city driving mode and high speed mode. The results indicate that the maximum wall temperature of DPF increase with increasing 'L/D' in 'High speed mode'. For 'City driving mode', the maximum wall temperature decreases with increasing 'L/D' in the range of $'L/D{\geq}0.6'$. The maximum temperature decreases with increasing cell density because heat conduction and heat capacity are increased. It is also found that the effect of amount of soot loading on light-off time is negligible.

• Korean Institute of Interior Design Journal
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• v.27 no.1
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• pp.21-28
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• 2018

Environmental issues had arisen following industrialization with rapid physical growth of city and its consequences: widened metropolitan areas, uncontrolled reconstructions of new metropolitan areas, many social issues, such as declines of existing metropolitan areas. Due to these issues, new development policies have been made in order to find identities and reconstruct new images of cities. This research aims to remind the meaning of conservation of modern construction and building re-use, and to identify values of modern architectures in the context of a city. Regeneration of cities is not only finding national identities, but also expecting to increase inflow of foreign travellers. However, this regeneration hasn't stayed sustainable, focusing only on short-term curing of the problem in limited areas. This work analyzes cases of modern architecture, historic buildings from various cultures: Western, Japanese, Chinese. The result of the analysis shows that the value of existing buildings and citizen participation is necessary to revitalize cities. Four characteristics have been also identified: historic relationship, spatial identity, spatial presence, and approachable efficiency. For a potential solution, cities need to be viewed from multiple perspectives to find a method to generate new vitality for a city whose values should be recognized as an asset through sustainable re-use, by transforming modern construction as a heritage.

• Korean Journal of Microbiology
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• v.24 no.4
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• pp.364-369
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• 1986

A procedure for the preparation, regeneration and fusion of protoplasts of Streptomyces tubercidicus was confirmed. Also, protoplast releasingprocesses from mycelia were observed by scanning electron microscope. Three types of protoplasts releasing processes-from the hyphal tip, hyphal end regions and lateral regions of the hyphae-were observed. More than 17% regeneration efficiency was obtained by regeneration medium that is composed of tryptone-yeast extract-sodium acetate-$MgCl_2-CaCl_2$-sucrose. Optimal concentrations of $Ca^{++},\;Mg^{++}$ and sucrose in the regeneration medium were 50mM, 0.4-0.5M respectively. Above 30% of fusion frequency of the protoplasts derived from two auxotrophic strains of S. tubercidicus was induced by polyethylene glycol 4000(60% w/v).

• Journal of Environmental Health Sciences
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• v.27 no.4
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• pp.9-14
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• 2001

This study was performed to develop the modified FGD(Flue Gas Desulfurization) process which can eliminate the possibility of generating secondary pollutants. Limestone was regenerated by adding ammonium hydroxide and carbon dioxide, and reusing it as a absorbent in FGD gypsum Process. A series of the new or modified FGD process which include desulfurization and regeneration limestone from CaSO$_3$. 1/2H20 and CaSO4 . 2H2O, were carried out under various experimental conditions. The results showed that the optimum injection ratio for regeneration of limestone was 0.3 ml/min of CO2 flow rate, 2 ml of NH4OH per 0.01 M of regent grade CaSO4 . 2H20O and the optimum regeneration temperature was 50. The increaser was the number of times of limestone regeneration, the faster was the breakthrough point of desulfurization at the desulfurination process which the regenerated limestone was used. Then the efficiency of desulrurization was decreased. This study can be confirmed the possibility for reuse of regenerated limestone due to the similarity of desulfurization characteries both reagent grade calcium carbonate and regenerated calcium carbonate. Finally, it appeared that the new technology using regenerated 1imestone can be applied to the FGD process.

• Journal of Plant Biotechnology
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• v.33 no.4
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• pp.237-242
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• 2006

Commercial cultivars and elite germplasms of barely (Hordeum vulgare L) are still recalcitrant to genetic transformation because of the lack of an efficient regeneration system. In this study, we established an efficient plant regeneration procedure from embryogenic calli derived from mature embryos. Callus induction from germinated mature embryos was best as over 95% in CIM medium (CI medium containing $2.5mg/{\ell}$ dicamba) under dark incubation. Development of embryogenic callus was highest as over 50% in CI3D medium (EC medium supplemented with $3mg/{\ell}$ 2,4-D). The highest regeneration of plants from embryogenic callus (40%) was obtained with CIS medium ($SI+1mg/{\ell}IAA\;and\;2mg/{\ell}\;BA$). These plant regeneration conditions could be useful in improving barley transformation efficiency.