• 에너지공학
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• 제7권1호
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• pp.73-80
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• 1998

Zinc titanate 탈황제를 제조하여 연료가스의 고온탈황에 사용된 탈황제의 재생에 대해서 연구하였다. 준비된 탈황제의 Zn/Ti 몰비는 1.5이고 반응기는 내경 1 cm와 3 cm의 석영관 고정층반응기들을 사용하였다. 고온에서 zinc titanate 탈황제의 재생은 발열반응을 수반하여 탈황제의 물성을 저하시킨다. 따라서 zinc titanate 탈황제의 가장 적합한 재생조건을 선정하기 위해서 반응온도, 산소함량, 유량변화, steam 함량 등을 변화시키면서 재생반응을 실험하였다. 탈황-재생의 실험동안 H2S와 SO2의 파과곡선을 구하였다. 또한 반응실험 전후의 탈황제의 물성을 SEM, XRD, Hg-porosimetry 및 BET로 분석하였다. 이런 결과들로부터 zinc titanate 탈황제에 가장 적합한 재생조건은 $650^{\circ}C$, O2 함？ 5%, steam 함량 10% 이상이라는 결론을 얻었다.

• Journal of Plant Biotechnology
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• 제36권4호
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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.

• 미생물학회지
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• 제30권6호
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• pp.514-518
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• 1992

The present study has been perromed to investigate the optimal conditions for protoplast formation and regeneration of oleandomycin-producing Streptomyces antibioticus (S. antibioticus) KCTC 1081. Mycelia were grown in YME medium containing 0.2% (w/v) glycine and converted into the protoplast by incubating at 35.deg.C for 60 minutes in protoplast buffer (P buffer) containing 4 mg/ml lysozyme. The reversion of protoplasts to the normal filamentous state was examined by the growth on various synthetic agar media. A high reversion rate was obtained by incubating the protoplasts on a hypertonic agar medium containing 20 mM $Mg^{++}$, 5 mM $Ca^{++}$ and 0.3 M sucrose at 28.deg.C for 5 days. From these experiments, we established the improved regeneration medium and a protocol which supports higher and more consistent levels of regeneration of S. antibioticus protoplasts. The regenerant showed an increased antimicrobial activity compared with that of the initial strain.n.n.

• 한국연소학회지
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• 제10권4호
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• pp.10-17
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• 2005

Sustaining of flame stability of the burner installed in Dielsel exhaust pipe is very difficult because of steep fluctuation of pressure and flow rate. A burner for DPF (Diesel Particulate Filter) which clogged by collected soot regeneration has been made of metal fiber for the purpose of realization of flame stability even in unfavorable condition of Diesel engine exhaust. Flame stability of the metal fiber burner has been investigated in various condition of engine operation. It has been identified that metal fiber burner with liner which has swirl guide vane presents excellent flame stability even in the higher engine revolutions than 3000rpm and sudden variation. The results offer the possibility of development of full flow burner system for DPF regeneration.

• 융복합기술연구소 논문집
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• 제1권1호
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• pp.41-47
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• 2011

With the world-wide demand on the emission minimization, the needs on the diesel aftertreatment devices with high efficiency are also increasing. In order to effectively develop or design a high-performance diesel particulate filter, a clear understanding on the deposition and regeneration mechanism is required. In the present study, a theory on the lumped parameter model for wall-flow type diesel particulate filters is described focusing on the deposition efficiency, pressure drop inside the filter. The fourth order explicit Runge-Kutta method is utilized for the mass flow rate computation. Engine operation modes with controlled and uncontrolled regeneration options are selected. The computational lumped parameter model is validated by comparing the computed results with the measured data.

• Bulletin of the Korean Chemical Society
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• 제20권12호
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• pp.1447-1450
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• 1999

Countercurrent oxygen reaction (COR) was developed and evaluated for regeneration of exhausted activated carbon. Whether the regeneration technique is feasible or not is affected strongly by gradual loss and physical changes of activated carbon, energy consumption, and effective removal of adsorbed materials during the process. Various parameters such as reaction temperature, the loss of activated carbon, surface area, pore volume, surface structure, adsorptive property, etc. were examined to determine the effectiveness of COR. The results of these tests showed that the parameters were strongly dependent on oxidant flow rate, and suggest that the newly developed COR is comparable and, in some ways, possibly superior to conventional regeneration techniques because the overall process runs in a single step and is less energy intensive, and also because the adsorptive capacity of exhausted activated carbon was completely recovered.

• 자동차안전학회지
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• 제13권3호
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• pp.54-59
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• 2021

Diesel engines emit PM and NOx during combustion. This is the main culprit of fine dust, which seriously affects the atmospheric environment. In particular, large-sized diesel vehicles over 3.5 tons emit a greater amount of pollutants because of their large displacement. The occurrence of vehicle abnormalities in this large-scale diesel vehicle causes even greater problems in the atmospheric environment. It was confirmed that there were many problems caused by natural regeneration DPF among large-sized diesel vehicles. Therefore, the most effective maintenance plan is suggested.

• Medical Lasers
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• 제10권1호
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• pp.15-21
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• 2021

As technology advances at a rapid rate, innovations in regenerative medicine will eventually include the use of energy-based therapeutics, such as low intensity-pulsed ultrasound stimulation (LIPUs), pulsed electromagnetic field stimulation (PMFs), and low-level laser/light therapy (LLLt) or photobiomodulation therapy (PBMt). Among these treatments, LLLt/PBMt attracted significant attention by the turn of the century, as evidenced by the numerous publications compared to LIPUs and PMFs, particularly for augmented bone regeneration (ABR). This is a testament of how the maturation of technology and scientific knowledge leads to latent compounded applications, even when the value of a technique is reliant on empirical data. This article reviews some of the notable investigations using LLLt/PBMt for bone regeneration published in the past decade, focusing on how this type of therapy has been utilized together with the existing regenerative medicine landscape.

• 대한의용생체공학회:의공학회지
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• 제43권6호
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• pp.434-440
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• 2022

Liver transplantation is a critical used treatment method for patients with end-stage liver disease. The number of cases of living donor liver transplantation is increasing due to the imbalance in needs and supplies for brain-dead organ donation. As a result, the importance of the accuracy of the donor's suitability evaluation is also increasing rapidly. To measure the donor's liver volume accurately is the most important, that is absolutely necessary for the recipient's postoperative progress and the donor's safety. Therefore, we propose liver segmentation in abdominal CT images from pre-operation, POD 7, and POD 63 with a two-dimensional U-Net. In addition, we introduce an algorithm to measure the volume of the segmented liver and measure the hepatectomy rate and regeneration rate of pre-operation, POD 7, and POD 63. The performance for the learning model shows the best results in the images from pre-operation. Each dataset from pre-operation, POD 7, and POD 63 has the DSC of 94.55 ± 9.24%, 88.40 ± 18.01%, and 90.64 ± 14.35%. The mean of the measured liver volumes by trained model are 1423.44 ± 270.17 ml in pre-operation, 842.99 ± 190.95 ml in POD 7, and 1048.32 ± 201.02 ml in POD 63. The donor's hepatectomy rate is an average of 39.68 ± 13.06%, and the regeneration rate in POD 63 is an average of 14.78 ± 14.07%.

• 한국식품영양과학회지
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• 제43권4호
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• pp.516-521
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• 2014

야관문 추출물의 피부재생능력을 알아보고, 창상을 유발한 실험동물 모델에서 창상 치유 효과를 검증하고자 6개 군(NO, CO, PC, LCL, LCM, LCH)으로 나누어 5주간 실험하였다. Elastase 저해 활성을 평가한 결과 LCM군에서 항산화제인 BHA보다 2.7%($52.39{\pm}4.52$ vs $53.88{\pm}1.85$) 낮은 수치를 나타내었으며, collagenase 저해 활성을 평가한 결과 LCM군에서 BHA보다 7%($37.68{\pm}2.91$ vs $35.19{\pm}7.80$) 더 높은 활성을 나타내었다. 창상유발 21일에 LCL군, LCM군 및 LCH군의 왼쪽 창상 면적은 CO군과 비교하여 각각 54.2%, 53.5% 및 48.7% 현저한 창상면적 감소를 보였다. 이로서 야관문 추출물은 피부상피조직의 재생과 교원질의 합성을 도와 외과적 창상에 치료 효과가 있는 것으로 판단된다.