• 한국식품영양학회지
• /
• 제22권2호
• /
• pp.261-271
• /
• 2009

Deep sea water exists at depths of over 200m under the sea. As no sunlight reaches it, photosynthesis does not take place within it, and it contains no organic matter. In addition, its temperature is maintained at a stable low level throughout the year, so it does not get mixed with the sea water on the surface. It contains a large amount of nutritious salts, whose cleanness is maintained. It is a marine resource that has matured for a long period of time. Research into deep sea water, which started in the 1970s, has been made around the whole world, including the USA and Japan. In Korea, research has been active in this area since 2000. As there has been a good amount of research into industrial applications for deep sea water, since 1993, patents for the relevant technologies have been applied. This paper intends to provide a resource to researchers of deep sea water, by summarizing of all domestic deep sea water-related patents applied with Korean Intellectual Property Office from 1993 to 2008. This research was conducted using a computer and KIPRIS Database owned by the Korea Institute of Patent Information. 'Deep sea water' was used as the search keyword. A total of 222 Korean patents relating to deep sea water have been registered on the basis of IPC. Of these, 126 patents relate to the manufacturing and the treatment of foods, foodstuffs, or non-alcoholic beverages(A23L), while 50 patents relate to the production for medical, dental, or cosmetic purposes(A61K). 38 patents relate to water purification, treatment of wastewater, sewage and sludge (C02F), while 8 patents relate to fishery and farming(A01K). In summary, it was found that studies for the practical use of deep sea water have been conducted in relation to the manufacturing and the treatment of foods, foodstuffs, beverages, and cosmetics.

• 한국자동차공학회논문집
• /
• 제10권1호
• /
• pp.32-44
• /
• 2002

Selective catalytic reduction of nitric oxide by methane in the presence of excess oxygen was investigated over copper and cobalt ion-exchanged ZSM-5 zeolites. Copper ion-exchanged ZSM-5(Cu-ZSM-5) has the limitations for commercial applications to lean-bum gasoline and diesel engines due to low thermal stability and resistance to water vapor and sulfur dioxide. But cobalt ion-exchanged ESM-5(Co-ZSM-5) is more active at high temperatures and also stable to water vapor and sulfur dioxide for catalytic reduction of nitric oxide by methane. The catalytic activity of Cu-ZSM-5 for NO reduction increases with increasing temperatures, reaches the maximum conversion of 23.0% at 350\"C. and then decreases with higher temperatures. In the meantime catalytic activities of Co-ZSM-5 show the maximum conversion of 25.8% at $500^{\circ}C$ Therefore Co-ZSM-5 catalysts have higher thermal stability at high temperatures. Catalytic activities of both zeolites were remarkably enhanced with the existence of oxygen in the exhaust. It is noted that the catalytic activity of Cu-ZSM-5 decreases with the increasing concentration of methane while the catalytic activity of Co-ZSM-5 decreases with increasing contents of methane in the exhaust. This may imply the existence of different paths of NO reduction by methane in the presence of excess oxygen fur Cu-ZSM-5 and Co-ZSM-5 catalysts. For binary metal ionexchanged ZSM-5, the primary ion-exchanged metal may be masked by secondary ion-exchanged component, which plays the important role for catalytic activities of binary metal ion-exchanged ZSM-5, Therefore CuCo-ZSM-5 catalysts show the similar volcano-shaped curves to Cu-ZSM-5 catalysts between the activity and temperature. It Is interesting that the activities of CoCu-ZSM-5 catalysts indicate almost no dependence on the concentration of methane in the exhaust.aust.

• 한국신재생에너지학회:학술대회논문집
• /
• 한국신재생에너지학회 2008년도 춘계학술대회 논문집
• /
• pp.13-16
• /
• 2008

Solid oxide fuel cell(SOFC) is an electrochemical energy conversion system with high efficiency and low-emission of pollution. In order to reduce the operating temperature of SOFC system under $800^{\circ}C$, the thickness reduction of YSZ electrolyte to be as thin as possible, e.g., less than 10 ${\mu}m$ are considered with the microstructure control and optimum design of unit cell. Methods for reducing the thickness of YSZ electrolyte have been investigated in coin cell. Moreover, a large unit cell($8cm{\times}8cm$) for SOFC was fabricated using an anode-supported electrolyte assembly with a thinner electrolyte layer, which was prepared by a tape casting method with a co-sintering technique. we studied the design factors such as active layer, electrolyte thickness, cathode composition, etc,. by the coin type of unit cell ahead of the fabrication process of a large unit cell and also reviewed about the evaluation technique of a large size unit cell such as interconnect design, sealing materials and current collector and so forth. Electrochemical evaluations of the unit cells, including measurements such as power density and impedance, were performed and analyzed. Maximum power density and polarization impedance of coin cell were 0.34W/$cm^2$ and $0.45{\Omega}cm^2$ at $800^{\circ}C$, respectively. However, Maxium power density of a large unit cell($5cm{\times}5cm$) decreased to 0.21W/$cm^2$ at $800^{\circ}C$ due to the increase of ohmic resistance. However, It was found that the potential value of a large unit cell loaded by 0.22A/$cm^2$ showed 0.76V at 100hrs without the degradation of unit cell.

• Journal of Astronomy and Space Sciences
• /
• 제17권1호
• /
• pp.39-44
• /
• 2000

lUE 저분산 자로플 가지고 44i Boo, W UMa, AW UMa및 VW Cep에서 나오는 자외선 방출선들의 특징을 조사하였다 단파장영역과 장파장영역에서의 방출선 선세기를 구하여, 이를 자$\boxUl$선 등급으로 변환하여 광도곡선을 얻었다 단파장 영ff에서 나오는 방출선인 C I, C II, C IV, SiIV, N V에 대한 선세기를 구한 결파, C IV가 모든 별에서 가장 센 방출을 보였으며. Si IV와 NV는 비교적 작은 양의 선세기를 나타내었다. 4개의 W UMa 별 쿵에근 44i Boo가 가장 높은 선세기를 보였으며, 단과장 영역에서는 위상 0.2와 0 8부근에서 자외선 팡도가 maximup을 보이는 변광을 확인하였다 또한, 전이영역에서 나오는 C IV, Si IV, N V 방출선을 합하여 이를 극소기의 태양값과 비교하여 태양보다 최대40배의 높은 활동성을 가지고 있음을 알았다. 짧은 주기를 갖는 별,즉 44i Boo, W UMa, AW UMa순으로 전이영역의 헐동성이 감소하는 것으로 나타났다. 장 파장 영역에서는 AW UMa와 VW Cep의 Mg ll 방출선을 조사하였는데, 단파장의 방출선 보다 뚜렷한 주기적 변광을 보였으며, 이를 이응하여 두 별의 유효온도를 추정하였다..

• Journal of Microbiology and Biotechnology
• /
• 제23권11호
• /
• pp.1598-1609
• /
• 2013

Organochlorine pesticide residues continue to remain as a major environmental threat worldwide. Lindane is an organochlorine pesticide widely used as an acaricide in medicine and agriculture. In the present study, a new lindane-degrading yeast strain, Pseudozyma VITJzN01, was identified as a copious producer of glycolipid biosurfactant. The glycolipid structure and type were elucidated by FTIR, NMR spectroscopy, and GC-MS analysis. The surface activity and stability of the glycolipid was analyzed. The glycolipids, characterized as mannosylerythritol lipids (MELs), exhibited excellent surface active properties and the surface tension of water was reduced to 29 mN/m. The glycolipid was stable over a wide range of pH, temperature, and salinity, showing a very low CMC of 25 mg/l. Bio-microemulsion of olive oil-in-water (O/W) was prepared using the purified biosurfactant without addition of any synthetic cosurfactants, for lindane solubilization and enhanced degradation assay in liquid and soil slurry. The O/W bio-microemulsions enhanced the solubility of lindane up to 40-folds. Degradation of lindane (700 mg/l) by VITJzN01 in liquid medium amended with bio-microemulsions was found to be enhanced by 36% in 2 days, compared with degradation in 12 days in the absence of bio-microemulsions. Lindane-spiked soil slurry incubated with bio-microemulsions also showed 20-40% enhanced degradation compared with the treatment with glycolipids or yeast alone. This is the first report on lindane degradation by Pseudozyma sp., and application of bio-microemulsions for enhanced lindane degradation. MEL-stabilized bio-microemulsions can serve as a potential tool for enhanced remediation of diverse lindane-contaminated environments.

• 한국통신학회논문지
• /
• 제11권3호
• /
• pp.172-178
• /
• 1986

스위치드 커패시터 필터(Switched-capacitor filter)의 유리한 점은 IC화 할 때 능동 RC회로의 RC적(RC Product)에 해다아는 것이 커패시턴스의 비로 되어 정확하게 그 값을 유지하는 것이 쉽고 클럭주파수에 의하여 중심주파수를 선형적으로 변화시킬 수 있다는 것이다. 본 논문에서는 프로그램 가능한 2차 SC필터를 구성한 후 디지털 신호에 의하여 중심주파수, 선택도 및 최대이득이 제어가능함을 실험을 통하여 입증하였다. 실험결과 필터의 ${omega}_0$는 모든 수동소자에 대해 저감도를 유지할 수 있었으나 스위치의 기생용량이 커패시터의 비에 미치는 영향은 피할 수 없었다. SC 필터는 클럭주파수, 저항 어레이등에 의하여 전달특성을 가변시킬 수 있으므로 디지탈 신호의 처리나 음성의 분석 및 합성에도 이용될 수 있을 것이다.

• 한국환경보건학회지
• /
• 제38권4호
• /
• pp.360-368
• /
• 2012

Objective: This study was carried out to use pine needles as a passive air sampler (PAS) of atmospheric Polychlorinated Biphenyls (PCBs). Methods: PCB concentrations in ambient air ($C_a$, ng/$m^3$) and deposited on pine needles ($C_p$, ng/g dry) were analyzed simultaneously from June 1 to December 31. Air samples were taken using a low volume PUF active air sampler and the overall average air volume was about 900-1,000 $m^3$. Pine needles were collected at the end of August and December near the air sampler. Results: $C_a$ were higher at higher air temperature and lower chlorinated PCB congeners, but $C_p$ showed irregular distribution. The average PCB sampling rates from air to pine needles were 0.116 (0.002-0.389) $m^3$/day - g dry. Conclusions: A poor correlation was shown between $C_a$ and $C_p$. However, a good correlation was shown between the logarithm of octanol-air partitioning coefficient ($logK_{oa}$) and log ($C_p/C_a$), and the interrelation was better with longer sampling time (June to December) than shorter sampling time (June to August). The average PCB sampling rates from air to pine needles were the lowest with respect to PUF disk, XAD-2 resin and semipermeable membrane devices (SPMDs) PAS. The average ratio ($C_{a-calc}/C_{a-meas}$) of calculated ($C_{a-calc}$) and measured ($C_{a-meas}$) PCB concentration was 0.69 with a shorter sampling time and 1.24 with a longer, so $C_{a-calc}$ was close to $C_{a-meas}$. It was found that pine needles can be used as PAS of atmospheric PCBs, and are especially suitable for long-time PAS.

• Parasites, Hosts and Diseases
• /
• 제54권4호
• /
• pp.415-421
• /
• 2016

The drug-resistance of malaria parasites is the main problem in the disease control. The huge Brazilian biodiversity promotes the search for new compounds, where the animal kingdom is proving to be a promising source of bioactive compounds. The main objective of this study was to evaluate the antiplasmodial and cytotoxic activity of the compounds obtained from the toad venoms of Brazilian Amazon. Toad venoms were collected from the secretion of Rhinella marina and Rhaebo guttatus in Mato Grosso State, Brazil. The powder was extracted at room temperature, yielding 2 extracts (RG and RM) and a substance ('1') identified as a bufadienolide, named telocinobufagin. Growth inhibition, intraerythrocytic development, and parasite morphology were evaluated in culture by microscopic observations of Giemsa-stained thin blood films. Cytotoxicity was determined against HepG2 and BGM cells by MTT and neutral red assays. The 2 extracts and the pure substance ('1') tested were active against chloroquine-resistant Plasmodium falciparum strain, demonstrating lower $IC_{50}$ values. In cytotoxic tests, the 2 extracts and substance '1' showed pronounced lethal effects on chloroquine-resistant P. faciparum strain and low cytotoxic effect, highlighting toad parotoid gland secretions as a promising source of novel lead antiplasmodial compounds.

• Bulletin of the Korean Chemical Society
• /
• 제35권7호
• /
• pp.1985-1988
• /
• 2014

$Cu_2ZnSnSe_4$ (CZTSe) thin films were synthesized on transparent conducting oxide glass substrates via a simple, non-toxic, and low-cost process using a precursor solution paste. A three-step heating process (oxidation, sulfurization, and selenization) was employed to synthesize a CZTSe thin film as an absorber layer for use in thin-film solar cells. In particular, we focused on the effects of sulfurization conditions on CZTSe film formation. We found that sulfurization at $400^{\circ}C$ involves the formation of secondary phases such as $CuSe_2$ and $Cu_2SnSe_3$, but they gradually disappeared when the temperature was increased. The formed CZTSe thin films showed homogenous and good crystallinity with grain sizes of approximately 600 nm. A solar cell device was tentatively fabricated and showed a power conversion efficiency of 2.2% on an active area of 0.44 $cm^2$ with an open circuit voltage of 365 mV, a short current density of 20.6 $mA/cm^2$, and a fill factor of 28.7%.

• 한국식품조리과학회지
• /
• 제23권3호통권99호
• /
• pp.327-336
• /
• 2007

Life-style factors often include social relationships as well as consumption, entertainment and dress patterns. They also typically reflect an individual's attitudes, values and worldview. Life-style types have become and an important factor for segmenting customer markets ever since significant relationships between life-style and customers' behavior was proven. This study examined the relationships between the life-styles of young customers' and the important attributes of foodservice encounters. Factors analysis with VARIMAX and K-means cluster analysis were conducted to group the subjects by life-style. According to the factors analysis, four underlying dimensions were identified and labeled: (1) 'actively fashioned', (2) 'luxury picky', (3) 'healthy toward', and (4) 'utilitarian leisure'. Based on the factor scores derived from the factors analysis, the K-means cluster analysis classified three groups as statistically significant using ANOVA(p<0.05). The overall mean score for the 3rd cluster 'trendy-active picky' was higher than the other two clusters, and represented very picky attitudes about foodservice attributes. The 3rd cluster also seemed to apply higher standards to all of the foodservice attributes. By order of importance, the most important attributes of the 2nd cluster 'pursue-utilitarian leisure' were food serving time, automation systems, server's hygienes, employee kindness, time in line, and menu variety. In spite of low concerns for the life-style attributes, the first cluster 'passively indifferent' recognized menu variety, food sanitation, food serving time, server's hygiene, menu price, air circulation, and room temperature as important. These results suggest that young diners in Korea could be classified by their diverse life-styles that are represented as trendy, utilitarian, and indifferent and will hopefully contribute to the foodservice industry's ability to segment customer characteristics by different life-styles in Korea.