• 제목/요약/키워드: Regeneration ratio

검색결과 282건 처리시간 0.022초

Zoysiagrass japonica의 효율적인 재분화체계에 관한 연구 (High Efficiency of Plant Regeneration from Seed-Derived Callus of Zoysiagrass cv. Zenith)

  • ;이종민;김두환
    • 아시안잔디학회지
    • /
    • 제12권4호
    • /
    • pp.195-202
    • /
    • 1998
  • The development of a protocol for high efficiency of embryogenic callus separation, maintenance and plant regeneration from the seeds of zoysiagrass cv. Zenith was studied. Embryogenic callus ratio is absolutely determined by genotype, but by adding high concentration of copper into medium, changing light condition and maintaining callus on initial induction medium for 8∼10 weeks, embryogenic callus can be easily distinguished and its growth can be promoted. There were significant differences among selected callus lines (each from one seed) according to their growth rates and regeneration percentages. Callus pre-treatment with activated charcoal inhibited callus growth, increased the level of precocious germination during culture and promoted shoot cluster formation after transfer to regeneration medium. For long-term callus maintenance, N6AA medium was better than MS medium, because the former inhibited non-embryogenic callus formation and kept vigor of embryogenic callus. The best callus lines Z-(5) has been successfully used for transformation and somaclonal variation selection in our laboratory.

  • PDF

재생 입구 직접증발냉각기 적용이 제습냉방시스템 성능에 미치는 영향 (Effects of performance analysis of a desiccant cooling system with a direct evaporative cooler in the regeneration process)

  • 다쉬울찌우타스;오명도
    • 대한설비공학회:학술대회논문집
    • /
    • 대한설비공학회 2009년도 하계학술발표대회 논문집
    • /
    • pp.633-638
    • /
    • 2009
  • In this study the performance analysis and cooling capacity of desiccant cooling system incorporating regenerative cooler and direct evaporative cooler in the regeneration air inlet were investigated on the condition of low regeneration temperature and time rotation 180s and area ratio of regeneration to dehumidification section 0.7. The cooling capacity and COP are evaluated at various effectiveness values of the direct evaporative cooler or the regenerative evaporative cooler. As either of effectiveness of the regenerative and direct evaporative coolers of desiccant cooling system increases, both the cooling capacity and COP increase, but effectiveness value of regenerative cooler gives the opposite effect on the system performance. It is found that effectiveness of regenerative cooler less than 0.7 shows the optimum cooling capacity.

  • PDF

연소 후 CO2 포집을 위한 흡수제의 재생반응에 의한 성능 해석 (Performance Analysis of Absorbent for Post-combustion CO2 Capture by Regeneration)

  • 길태형;이동호;조성호;이창근;박영성;류호정
    • 한국수소및신에너지학회논문집
    • /
    • 제27권1호
    • /
    • pp.83-94
    • /
    • 2016
  • Performance of absorbent for post-combustion $CO_2$ capture was measured and discussed. Fully saturated fresh absorbent (P2-15F) and absorbents sampled from absorption and regeneration reactor of continuous $CO_2$ capture process, P2-15A, P2-15R, respectively, were used as representative absorbents. Small scale fluidized bed reactor (0.05 m I.D., 0.8 m high) which can measure exhaust gas concentration and weight change simultaneously was used to analyze regeneration characteristics for those absorbents. Exhausted moles of $CO_2$ and $H_2O$ were measured with increasing temperature. $H_2O/CO$ ratio and working capacity were determined and discussed to confirm reason of reactivity decay after continuous operation. Moreover, possibility of side reaction was checked based on the $H_2O/CO_2$ mole ratio. Finally, suitable regeneration temperature range was confirmed based on the trend of working capacity with temperature.

영도구 도시재생사업 대상지의 상권변화 분석 (Analysis of Changes of Commercial Areas in Yeongdo-gu Urban Regeneration Region)

  • 이혜인;오광석
    • 한국콘텐츠학회논문지
    • /
    • 제22권8호
    • /
    • pp.367-376
    • /
    • 2022
  • 본 연구는 도시재생사업으로 인한 지역 활성화로 영도구 도시재생사업 대상지의 상권변화를 살펴보고자 한다. 도시쇠퇴로 인한 지역 침체의 심화는 도심 상업 기능의 쇠퇴를 가속할 수 있기에, 경제활동이 저하된 원도심을 활성화하기 위한 상권 활력 증진 측면에서 이해할 수 있다. 도시재생사업 대상지의 상권변화 분석을 위해, 상업 활성화를 살펴보는 상점 밀도, 업종 다양성을 지표로 산출하여 비교 분석하였다. 또한, 인구의 유입과 집객에 영향을 미치는 음식점업과 카페 비율을 통해 대상지 상권의 동태적 변화를 확인하였다. 연구 결과 영도구 내 도시재생사업 대상지에서 상점 밀도와 업종 다양성이 증가하는 추세를 보였다. 음식점업과 카페 비율의 경우 큰 차이를 발견하기는 어려우나, 영선2동(흰여울문화마을)의 경우 상업적 변화가 상대적으로 크게 나타나는 것으로 확인하였다. 본 연구는 영도구 도시재생사업 대상지의 상업적 변화를 정량적으로 평가 분석하였다는 데 그 의의가 있다.

Risk Factors for Wound Dehiscence after Guided Bone Regeneration in Dental Implant Surgery

  • Kim, Young-Kyun;Yun, Pil-Young
    • Maxillofacial Plastic and Reconstructive Surgery
    • /
    • 제36권3호
    • /
    • pp.116-123
    • /
    • 2014
  • Purpose: The purpose of this study was to evaluate risks for wound dehiscence after guided bone regeneration (GBR) in dental implant surgery. Methods: Patients who received dental implant therapy with GBR procedure at Seoul National University Bundang Hospital (Seongnam, Korea) from June 2004 to May 2007 were included. The clinical outcome of interest was complications related to dental implant surgery. The factors influencing wound dehiscence, classified into patient-related factors, surgery-related factors and material-related factors, were evaluated. Results: One hundred and fifteen cases (202 implants) were included in this study. Wound dehiscence (19.1%) was considered a major complication. The risk of wound dehiscence was higher in males than in females (odds ratio=4.279, P =0.014). In the main graft, the allogenic group had the lowest risk of wound dehiscence (odds ratio=0.106, P =0.006). Though the external connection group had a higher risk of wound dehiscence than the internal connection group (odds ratio=2.381), the difference was not significant (P =0.100). Conclusion: In this study, male gender and main graft have the highest risk of wound dehiscence. To reduce wound dehiscence after GBR, instructions on postoperative care with supplementary procedure for the protection of the wound dehiscence is recommended, especially to male patients. A main graft with a gel base can reduce the risk of wound dehiscence.

재생입구 직접증발냉각기 적용이 제습냉방시스템 성능에 미치는 영향 (Effects of Performance Analysis of a Desiccant Cooling System with a Direct Evaporative Cooler in the Inlet of Regeneration Process)

  • 다쉬 울찌우타스;성상철;오명도;이대영
    • 설비공학논문집
    • /
    • 제22권5호
    • /
    • pp.328-335
    • /
    • 2010
  • The purpose of this study is to make an analysis of influence on the cooling capacity and COP of a desiccant cooling system with a regenerative evaporative cooler when a direct evaporative cooler was applied to the inlet of regeneration process of this system. We used cycle simulation in order to analyze the performance of this system. From the cycle simulation, we knew that the optimal rotation time of desiccant rotor was between 160s and 220s and hardly ever affected cooling capacity of desiccant cooling system when this system was operated at the outdoor air condition of $35^{\circ}$ and 40% RH and low regeneration temperature of $60^{\circ}$. Also there was optimal area ratio of regeneration to dehumidification between 0.7 and 1.0. Our results showed that it had a small effect on the system’s cooling capacity to install direct evaporative cooler at the inlet of regeneration process.

Late-term healing in an augmented sinus with different ratios of biphasic calcium phosphate: a pilot study using a rabbit sinus model

  • Lim, Hyun-Chang;Hong, Ji-Youn;Lee, Jung-Seok;Jung, Ui-Won;Choi, Seong-Ho
    • Journal of Periodontal and Implant Science
    • /
    • 제46권1호
    • /
    • pp.57-69
    • /
    • 2016
  • Purpose: The aim of this pilot study was to determine the osteoconductivity and dimensional stability of augmented sinuses using different ratios of biphasic calcium phosphate (BCP) in a rabbit sinus model. Methods: Each sinus of New Zealand white rabbits (2.5-3.5 kg) was assigned to one of two groups: BCP with a hydroxyapatite to ${\beta}$-tricalcium phosphate (HA:${\beta}$-TCP) ratio of 70:30 (group TCP30) and BCP with an HA:${\beta}$-TCP ratio of 30:70 (group TCP70). After preparing a window in the antral wall of a sinus, the Schneiderian membrane was elevated, and the applicable material was grafted. A fluorochrome calcein green was injected five days before euthanizing the animals at four months post-surgery. The specimens were analyzed histologically, histomorphometrically, and by using micro-computed tomography (micro-CT). Results: Micro-CT analysis revealed that the total augmented volume and the new bone volume did not differ significantly between the two groups whereas the resorption of materials was greater in the TCP70 group. The trabecular thickness, number, and separation also did not differ significantly between the two groups. Histomorphometrically, the areas of total augmentation, new bone, and residual material, as well as the ratio of new-bone-material contact did not differ significantly between the groups. Histologically, the residual particles were more scattered in the TCP70 group than in the TCP30 group. The fluorescence of the calcein green did not differ notably between the two groups. Conclusions: The osteoconductivity and dimensional stability of the two BCPs with different ratios tested in this study were comparable after four months of healing. Therefore, we conclude that both BCPs show promise as a bone substitute for sinus augmentation.

Regeneration of solid phase filter by chemical cleaning

  • Byung-Dae Lee
    • 한국응용과학기술학회지
    • /
    • 제41권1호
    • /
    • pp.19-26
    • /
    • 2024
  • Recently, separation membranes have been applied to fields such as water supply, sewage treatment, gray water reuse, and air pollution control. Chemical cleaning technology is attracting attention among the methods of reusing these expensive separation membranes. It was found that the separation membrane could be regenerated using chemical cleaning. Specifically, it was found that the use time of the separation membranes regenerated by chemical cleaning was sustainable for more than 1,700 hours. Additionally, it was found that the flux recovery ratio after chemical cleaning was maintained at least 60%. In addition, the flux recovery ratio of HYDREX 4710, an organic membrane cleaner, and 4703, an inorganic membrane cleaner, was 76% and 62%, respectively, showing the highest flux recovery ratio among the chemicals used. Considering that the target raw water of this study is biological secondary treatment water, it was suggested that chemical cleaning could be actively used to regenerate separation membranes in future water treatment.

연료가스의 고온 탈황에 사용된 Zinc Titanate의 재생 (Regeneration of Zinc Titanate Used for High Temperature Desulfurization of Fuel Gases)

  • 이태진;권원태
    • 에너지공학
    • /
    • 제7권1호
    • /
    • pp.73-80
    • /
    • 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.

  • PDF