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Effects of Fouling and Scaling on the Retention of Explosives in Surface Water by NF-the Role of Cake Enhanced Concentration Polarisation (지표수 조건의 나노여과공정에서 파울링 및 스케일링이 화약류 물질 잔류에 미치는 영향 연구 - 케익층 형성 및 농도분극 영향 분석)

  • Heo, Jiyong;Han, Jonghun;Lee, Heebum;Lee, Jongyeol;Her, Namguk
    • Journal of the Korean Geoenvironmental Society
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    • v.16 no.4
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    • pp.13-22
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    • 2015
  • The combined impact of Dissolved Organic Matter (DOM) fouling and inorganic ($CaSO_4,Ca_3(PO_4)_2$) scaling on the retention of TNT (2, 4, 6-Trinitrotoluene), RDX (Hexahydro-1, 3, 5-trinitro-1, 3, 5-triazine) and HMX (1, 3, 5, 7-Tetranitro-1, 3, 5, 7-tetrazocane) explosive contaminants by nano-filtration membrane were studied, since organic fouling and salt scaling are the major limitations for membrane filtration. Results reported here indicate that DOM fouling layer with a humic acid does not necessarily lead to an immediate loss of permeate flux but can result in a severe impact on the flux loss when both humic acid and inorganic scaltants were presented simultaneously. The $Ca_3(PO_4)_2$ mixed with humic acid showd most sever flux loss (42%) compared to that of only humic acid presence (8%). It could be a result that the scaling formation of the NF membrane was dominated by cake layer formation of DOM and it was along with pore blocking by the formation of crystals inside the porous active matrix of the NF membrane. In addition, these results indicated that the membrane selectivity of the explosives retention trended correlated with respect to increasing explosives size (listed by MW) based on greater steric interactions and followed the order (MW, g $mol^{-1}$; removal, %): HMX (296.15; 83%) ${\gg}$ RDX (222.12; 49%) ≋ TNT (227.13; 32%). Because the scaling and fouling layer could lead to a additional cake-enhanced concentration polarisation effect, the retention of explosives with the presence of humic acid in the feed solution and inorganic scaling formation on top of an organic fouling layer do not differ substantially retention from that of pure DI feed and NaCl solution.

A Numerical Study on the CO2 Leakage Through the Fault During Offshore Carbon Sequestration (해양지중에 저장된 이산화탄소의 단층을 통한 누출 위험 평가에 관한 수치해석 연구)

  • Kang, Kwangu;Huh, Cheol;Kang, Seong-Gil
    • Journal of the Korean Society for Marine Environment & Energy
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    • v.18 no.2
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    • pp.94-101
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    • 2015
  • To mitigate the greenhouse gas emission, many carbon capture and storage projects are underway all over the world. In Korea, many studies focus on the storage of $CO_2$ in the offshore sediment. Assurance of safety is one of the most important issues in the geological storage of $CO_2$. Especially, the assessment of possibility of leakage and amount of leaked $CO_2$ is very crucial to analyze the safety of marine geological storage of $CO_2$. In this study, the leakage of injected $CO_2$ through fault was numerically studied. TOUGH2-MP ECO2N was used to simulate the subsurface behavior of injected $CO_2$. The storage site was 150 m thick saline aquifer located 825 m under the continental shelf. It was assumed that $CO_2$ leak was happened through the fault located 1,000 m away from the injection well. The injected $CO_2$ could migrate through the aquifer by both pressure difference driven by injection and buoyancy force. The enough pressure differences made it possible the $CO_2$ to migrate to the bottom of the fault. The $CO_2$ could be leaked to seabed through the fault due to the buoyancy force. Prior to leakage of the injected $CO_2$, the formation water leaked to seabed. When $CO_2$ reached the seabed, leakage of formation water stopped but the same amount of sea water starts to flow into the underground as the amount of leaked $CO_2$. To analyze the effect of injection rate on the leakage behavior, the injection rate of $CO_2$ was varied as 0.5, 0.75, and $1MtCO_2/year$. The starting times of leakage at 1, 0.75 and $0.5MtCO_2/year$ injection rates are 11.3, 15.6 and 23.2 years after the injection, respectively. The leakage of $CO_2$ to the seabed continued for a period time after the end of $CO_2$ injection. The ratios of total leaked $CO_2$ to total injected $CO_2$ at 1, 0.75 and $0.5MtCO_2/year$ injection rates are 19.5%, 11.5% and 2.8%, respectively.

Induction of Apoptosis by Piceatannol in YD-15 Human Oral Cancer Cells (피세아타놀에 의한 YD-15 구강암세포의 세포자가사멸 유도 효과)

  • Lee, Hae-Nim;Jang, Hye-Yeon;Kim, Hyeong-Jin;Shin, Seong-Ah;Choo, Gang-Sik;Park, Byung-Kwon;Kim, Byeong-Soo;Jung, Ji-Youn
    • Journal of the Korean Society of Food Science and Nutrition
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    • v.44 no.7
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    • pp.975-982
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    • 2015
  • Piceatannol (trans-3,4,3',5'-trihydroxystilbene), a natural stilbene, is an analogue of resveratrol. In the present study, possible mechanisms by which piceatannol exerts its pro-apoptotic action in cultured human oral cancer YD-15 cells were investigated. To investigate whether or not piceatannol has effects on cancer cell viability, human oral YD-15 cells were treated with piceatannol (0, 50, and $100{\mu}M$). Piceatannol treatment ($100{\mu}M$) showed the strongest inhibition of cell proliferation and reduced cell viability in a dose-dependent manner. Chromatin condensation detected by DAPI staining significantly increased in a concentration-dependent manner, indicating apoptosis. Piceatannol treatment activated initiator Bax (pro-apoptotic) and cPARP in a concentration-dependent manner. Further, piceatannol induced down-regulation of Bcl-2 (anti-apoptotic). We also evaluated the activity of piceatannol against oral cavity cancer tumors in mice. Piceatannol-treated nude mice bearing YD-15 xenograft tumors exhibited significantly reduced tumor volume and weight due to the potent effect of piceatannol on tumor cell apoptosis, as determined by terminal deoxynucleotidyl transferase-mediated dUTP nick end labeling assay. Immunohistochemistry staining showed elevated expression of cleaved-caspase-3 as well as reduced expression of Ki-67 in the piceatannol-treated group. Therefore, piceatannol can be developed as a cancer preventive medicine due to its growth inhibitory effects and induction of apoptosis in human oral cancer cells.

Performance Estimation of Large-scale High-sensitive Compton Camera for Pyroprocessing Facility Monitoring (파이로 공정 모니터링용 대면적 고효율 콤프턴 카메라 성능 예측)

  • Kim, Young-Su;Park, Jin Hyung;Cho, Hwa Youn;Kim, Jae Hyeon;Kwon, Heungrok;Seo, Hee;Park, Se-Hwan;Kim, Chan Hyeong
    • Journal of Radiation Protection and Research
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    • v.40 no.1
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    • pp.1-9
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    • 2015
  • Compton cameras overcome several limitations of conventional mechanical collimation based gamma imaging devices, such as pin-hole imaging devices, due to its electronic collimation based on coincidence logic. Especially large-scale Compton camera has wide field of view and high imaging sensitivity. Those merits suggest that a large-scale Compton camera might be applicable to monitoring nuclear materials in large facilities without necessity of portability. To that end, our research group have made an effort to design a large-scale Compton camera for safeguard application. Energy resolution or position resolution of large-area detectors vary with configuration style of the detectors. Those performances directly affect the image quality of the large-scale Compton camera. In the present study, a series of Geant4 Monte Carlo simulations were performed in order to examine the effect of those detector parameters. Performance of the designed large-scale Compton camera was also estimated for various monitoring condition with realistic modeling. The conclusion of the present study indicates that the energy resolution of the component detector is the limiting factor of imaging resolution rather than the position resolution. Also, the designed large-scale Compton camera provides the 16.3 cm image resolution in full width at half maximum (angular resolution: $9.26^{\circ}$) for the depleted uranium source considered in this study located at the 1 m from the system when the component detectors have 10% energy resolution and 7 mm position resolution.

The Effects of Calcinated Calcium Solution Washing and Heat Treatment on the Storage Quality and Microbial Growth of Fresh-cut Broccoli (신선편이 브로콜리의 품질과 미생물 성장에 영향을 주는 소성칼슘 용액 세척 및 열처리 효과)

  • Kim, Ji Gang;Nimitkeatkai, Hataitip;Choi, Ji Woen;Lee, Sang Gyu
    • Protected Horticulture and Plant Factory
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    • v.21 no.4
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    • pp.411-418
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    • 2012
  • This study was conducted to investigate the effect of calcinated calcium (CC) alone or combination with heat treatment on storage quality and microbial growth in fresh-cut broccoli. Fresh broccoli samples were cut into small pieces and washed in normal tap water (TW), $50{\mu}L{\cdot}L^{-1}$ chlorinated water (pH 6.5), $1.5g{\cdot}L^{-1}$ CC, heat treatment in TW at $45^{\circ}C$, and CC dissolved in TW at $45^{\circ}C$ for 2 minutes separately. Samples were then packaged in $50{\mu}m$ polyethylene bags and stored at $5^{\circ}C$. Results revealed that like $50{\mu}L{\cdot}L^{-1}$ chlorine, washing in CC at normal water temperature was effective in reducing microbial population in fresh-cut broccoli samples. Washing with CC combined with heat treatment increased an electrical conductivity of fresh-cut broccoli. Combined heat treatments with TW and CC reduced aerobic plate count on fresh-cut broccoli, only in initial period of storage. But, later on heat treatment induced injury of fresh-cut broccoli resulting more microbial population compared to non heat treatment. However, samples treated with CC alone had good quality with low off-odor at the end of storage. Results suggest that CC, an environment-friendly sanitizer could be an alternative to chlorinated water for washing of fresh-cut broccoli without affecting sensorial quality.

Analysis of doctors' cognition of patient safety at general hospitals (일개 상급종합병원 의사들의 환자안전문화에 대한 인식 분석)

  • Yu, Eun-Yeong;Jung, Sang-Jin
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.6
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    • pp.2607-2616
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    • 2012
  • This study was designed to figure out patient safety culture of medical institutions and try to utilize the study results as basic data for analyzing doctor's awareness of patient safety culture. To this end, questionnaire survey was conducted from August 1st to September 5th, 2011, targeting doctors working at senior general hospitals located in G city, and 194 questionnaires were utilized for final analysis. The research results are as follows. First, there was a difference in awareness of deployment of staffs depending on gender, age, term of service in the hospital, contact with patients and working hours per week in relationship between subjects, wards and hospital safety culture, and organizational learning and teamwork in the ward turned out to be significant in accordance with working hours per week, and all sub-areas of the ward safety culture by departments. Second, feedback about the malpractice, communication, report on malpractice frequency and overall safety awareness were found to be significant by departments in relationship of subjects, medical incident reporting system, patient safety evaluation and overall level of consciousness, and the overall safety awareness showed significant results according to contact with patients and working hours per week. Third, there was a positive corelation in sub-areas of the ward and hospital safety culture awareness, overall recognition and patient safety evaluation, and a positive corelation with medical incident reporting system was found in all areas except for attitude of managers/immediate supervisors and that of hospital executives. Fourth, sub-areas of patient safety culture which has a effect on patient safety showed significant results in organizational learning, openness of communication, overall safety awareness, systematic cooperation between departments, feedback/communication and non-punitive response. In conclusion, to increase the level of the ward and hospital patient safety culture of doctors and implement medical incident reporting system faithfully, it is necessary to activate teamwork through organizational learning in the ward based on the adequate staffing and working hours, promote open communication between departments and provide feedback on medical malpractice, thereby establishing a cooperative system by departments and active support of hospital executives for patient safet.

Effects of Water Temperature and Estradiol-17β on the Sex Ratio and Growth of the Japanese Eel, Anguilla japonica (극동산 뱀장어, Anguilla japonica의 성비와 성장에 미치는 수온 및 estradiol-17β의 효과)

  • Kim, Dae-Jung;Lee, Nam-Sil;Kim, Shin-Kown;Lee, Bae-Ik;Seong, Ki-Baik;Kim, Kyung-Kil
    • Journal of Life Science
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    • v.23 no.12
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    • pp.1454-1459
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    • 2013
  • This study investigated the effects that water temperature and the administration of estradiol-17${\beta}$ (E2) had on the sex ratio and growth of the Japanese eel, Anguilla japonica. Glass eels (total length${\fallingdotseq}$6.5 cm) were differentiated into an E2 group and an E2-free group and then they were reared for about four months at three water temperature levels of $20^{\circ}C$, $24^{\circ}C$, and $28^{\circ}C$. The results showed that the young eels survived normally at the rearing water temperature of ${\geq}24^{\circ}C$, and grew to a mean size of 20 cm (total length). In the E2-free group, temperature was not found to increase the sex ratio (feminizing rates); however, the sex ratio of the E2-administrated group was found to be a little higher at a high temperature ($28^{\circ}C$). The growth of the E2 group was lower than the growth of the E2-free group at $24^{\circ}C$ and the E2 concentration levels in the plasma at $24^{\circ}C$ were found to be significant after the end of the E2 administration period (178 days). Therefore, we thought that long-term administration of E2 must be considered to be the reason for growth decline in spite of the prominent sex ratio effect. Our results indicate that temperature was not related to an increase in the feminizing rate (sex ratio) in the Japanese eel, Anguilla japonica, and other environmental factors (rearing density, salinity, etc.) that have the possibility of inducing ovarian differentiation must be investigated.

Influence of Elevated CO2 and Air Temperature on Photosynthesis, Shoot Growth, and Fruit Quality of 'Fuji'/M.9 Apple Tree (CO2 및 기온 상승이 '후지'/M.9 사과나무의 광합성, 신초생장 및 과실품질에 미치는 영향)

  • Kweon, Hun-Joong;Sagong, Dong-Hoon;Park, Moo-Yong;Song, Yang-Yik;Chung, Kyeong-Ho;Nam, Jong-Chul;Han, Jeom-Hwa;Do, Gyung-Ran
    • Korean Journal of Agricultural and Forest Meteorology
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    • v.15 no.4
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    • pp.245-263
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    • 2013
  • This study was conducted to find out the influence of elevated atmospheric $CO_2$ concentrations and air temperature on photosynthesis and fruit quality of 'Fuji'/M.9 apple trees and to investigate these to the effects of climate change during the last four years (2009-2012). The treatments employed were: 'Ambient' (ambient temperature + ambient $CO_2$ concentration); 'High $CO_2$' (ambient temperature + elevated $CO_2$ concentration); 'High Temp'. (elevated temperature + ambient $CO_2$ concentration); and 'High $CO_2$ + High Temp'. (elevated temperature + elevated $CO_2$ concentration). The elevated temperature plots were maintained at $4^{\circ}C$ higher than ambient air temperature, while the elevated $CO_2$ plots were maintained at 700 ${\mu}mol{\cdot}mol^{-1}$. Annual treatment period was applied from end of April to beginning of November for four years. Results showed that elevated $CO_2$ decreased stomatal conductance and leaf SPAD value, but increased photosynthetic rate, intercellular $CO_2$ concentration (Ci), and starch content of mesophyll tissue. In the vegetative growth, elevated temperature increased total number of shoot and total shoot growth per tree, but elevated $CO_2$ decreased average shoot length. In the fruit quality, elevated $CO_2$ increased soluble solid content, fruit red color, and ethylene production. In conclusion, elevated $CO_2$ increased photosynthetic rate of apples during the early growth, but effect of increased photosynthetic rate due to elevated $CO_2$ was decreased during latter growth stage. Elevated temperature, on the other hand, tended to decrease photosynthetic rate of apples during the early growth, but that tended to increase during latter growth stage. Both elevated $CO_2$ and temperature tended to decrease the degree of decreased photosynthetic rate due to each factor.

Effect of Timing of Nutrient Starvation during Transplant Production on the Growth of Runner Plants and Yield of Strawberry 'Seolhyang' (딸기 '설향' 육묘기 양분 공급 중단 시기가 자묘 생육 및 수량에 미치는 영향)

  • Kim, Dae-Young;Chae, Won Byoung;Kwak, Jung-Ho;Park, Suhyung;Cheong, Seung-Ryong;Choi, Jong Myung;Yoon, Moo Kyoung
    • Protected Horticulture and Plant Factory
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    • v.22 no.4
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    • pp.421-426
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    • 2013
  • This study was conducted to investigate the effects of timing of nutrient starvation during transplant production on growth of runner plants and yield of strawberry 'Seolhyang' (Fragaria ${\times}$ ananassa). Nutrient solution supply at the level of EC (electrical conductivity) 0.8 $dS{\cdot}m^{-1}$ was terminated at interval about 10 days between July 25 and September 5. As a result, the growth of above-ground part was inhibited while root growth increased when the nutrient starvation treatment had been brought forward to July 25. It also reduced the T/R ratio significantly and chlorophyll content was tended to be lower than the other treatment. In addition, it significantly promoted the budding, flowering and harvest of first flower cluster. On the other hand, the period of harvest was delayed more than two weeks when the nutrients were continuously supplied after the middle of August. An accumulated marketable fruit yield per plant until the end of January and February was 169 and 266g, respectively in the treatment of nutrient starvation on July 25, which was 71 and 12% increase, respectively, as compared with those in the treatment of September 5. Therefore, the appropriate nutrient starvation in the late season of strawberry nursery period could be expected the increase in yield and income during the winter season by promoting the flower bud differentiation as reducing the endogenous nitrate level of the plantlet.

Perceptions of the Retailers within Green Food Zone on the enforcement of the Special Act on the Safety Management of Children's Dietary Life (어린이 식생활 안전관리 특별법 시행에 대한 학교주변 판매업자 인식조사)

  • Lee, Seung-Sin;Yang, Deok-Soon;Lee, Jong-Hye;Lee, Young-Hee;Heo, Sun-Kyung
    • Journal of Food Hygiene and Safety
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    • v.27 no.1
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    • pp.55-62
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    • 2012
  • This study is a survey of regulatees' perception on main contents and enforcement effect of the Act, the retailers at food stores within Green Food Zone, for the effective enforcement of "The Special Act on the Safety Management of Children's Dietary Life" legislated in 2008. Percentage, frequency analysis, and T-test are derived from the survey carried out to the 175 retailers at food stores within Green Food Zone, across the country except Jejudo, for the two months March and April of 2011. The survey results are as follows. Over 80% of the respondents are aware of comprehensive policy for child food safety and the enforcement of 'the Special Act' and considering the rate of satisfaction on food safety information provided by government, over 90% of the respondents, virtually most of them, are satisfied. The rate of awareness of Green Food Zone is about 80% and that of outstanding business for children is about 50%, showing little perception of it. The comparison of the survey result of 2011 with that of 2010, which have the same questions to the retailers within Green Food Zone, still indicates a need for enhancement of understanding on absolute standard, though it showed fairly better improvement in general. Several proposals are given in this study based on the survey results, which will contribute to the children food safety and health improvement in the end.