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REFERENCE LINKING PLATFORM OF KOREA S&T JOURNALS
> Journal Vol & Issue
Ocean and Polar Research
Journal Basic Information
Journal DOI :
Korea Institute of Ocean Science & Technology
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Volume & Issues
Volume 34, Issue 4 - Dec 2012
Volume 34, Issue 3 - Sep 2012
Volume 34, Issue 2 - Jun 2012
Volume 34, Issue 1 - Mar 2012
Selecting the target year
A Review on Major Factors for Microalgae Biofuel Commercialization
Kang, Do-Hyung ; Heo, Soo-Jin ; Oh, Chulhong ; Ju, Se-Jong ; Jeon, Seon-Mi ; Choi, Hyun-Woo ; Noh, Jae Hoon ; Park, Se Hun ; Kim, Tae-Young ;
Ocean and Polar Research, volume 34, issue 4, 2012, Pages 365~384
DOI : 10.4217/OPR.2012.34.4.365
Microalgae are photosynthetic microorganisms that are highly productive in the presence of basic renewable natural sources (light,
, water and nutrients). They can synthesize lipids, carbohydrates and proteins in a small number of days. Subsequently, these carbon-captured products can be processed into both biofuels and valuable co-products. Additionally, microalgae would be an ideal feedstock for replacing land-based food crops with cellular products as high energy density transportation fuels. These microscopic organisms could contribute a significant amount of renewable energy on a global scale. In Korea, microalgae biofuel research was common in the early 1990s. The research activities were unfortunately stopped due to limited governmental funds and low petroleum prices. Interest in algal biofuels in Korea has been growing recently due to an increased concern over oil prices, energy security, greenhouse gas emissions, and the potential for other biofuel feedstock to compete for limited agricultural resources. The high productivity of microalgae suggests that much of the Korean transportation fuel requirements can be met by biofuels at a production cost competitive with the increasing cost of petroleum seen in early 2008. At this time, the development of microlalgal biomass production technology remains in its infancy. This study reviewed microalgae culture systems and biomass production, harvesting, oil extraction, conversion, and technoeconomical bottlenecks. Many technical and economic barriers to using microalgal biofuels need to be overcome before mass production of microalgal-derived fuel substitutes is possible. However, serious efforts to overcome these barriers could become a large-scale commercial reality. Overall, this study provides a brief overview of the past few decades of global microalgal research.
Inhibitory Effect of Zostera japonica on Growth of Human Cancer Cells
Jung, Myung Eun ; Hong, Joo Wan ; Lee, Jung Im ; Kong, Chang-Suk ; Chang, Jae-Soo ; Seo, Youngwan ;
Ocean and Polar Research, volume 34, issue 4, 2012, Pages 385~394
DOI : 10.4217/OPR.2012.34.4.385
In this study, crude extracts of the marine eelgrass Zostera japonica and their solvent-partitioned fractions were evaluated for their inhibitory effect against AGS, HT-1080 and MCF-7 human cancer cells using MTT assay. Each of the crude extracts (acetone/methylene, chloride, and methanol) of Z. japonica showed a significant inhibitory effect on the growth of human cancer cells. The combined crude extracts were partitioned between
and water. The organic layer was further partitioned between 85% aq. MeOH and n-hexane, and the aqueous layer was then fractionated into n-BuOH and
, successively. Growth inhibition effects of solvent-partitioned fractions from Z. japonica on human cancer cells increased in a dose-dependent manner. Among these tested samples, the 85% aq. MeOH fraction revealed good inhibitory effects on the growth of AGS and HT-1080 human cancer cells, while the n-hexane fraction exhibited good inhibitory effects on the growth of AGS and MCF-7 human cancer cells. In addition, 85% aq. MeOH and n-hexane fractions enhanced mRNA expression of p53 gene. These results suggest that there is further scope for the isolation of active compounds from Z. japonica, which should show much stronger anticancer activity.
Evidences of Intermittent Wind-Induced Flow in the Yellow Sea obtained from AVHRR SST Data
Seung, Young Ho ; Yoon, Jong-Hyuk ; Lim, Eun-Pyo ;
Ocean and Polar Research, volume 34, issue 4, 2012, Pages 395~401
DOI : 10.4217/OPR.2012.34.4.395
Ten-year AVHRR sea surface temperature data obtained in the Yellow Sea are put into EOF analyses. Temperature variation is predominated by the first mode which is associated with the seasonal fluctuation of temperature with annual range decreasing with the bottom depth. Since such a strong annual signal may mask the upwind or downwind flows occurring intermittently during the winter, only the data obtained during this season are put into EOF analyses. Every winter shows similar results. The first mode, explaining more than 90% of total variance, appears to be a part of the seasonal variation of temperature mentioned above. In the second mode, the time coefficient is well correlated with northerly winds to which the responses of the trough and shallow coastal areas are opposite to each other. A simple theoretical consideration suggests the following physical explanation: The northerly wind stress anomaly creates an upwind (downwind) flow over the trough (coastal) areas, which then induces a temperature increase (decrease) by advection of heat, and vice versa for the southerly wind stress anomaly. Hence, this paper provides further evidence of the intermittent upwind or downwind flows occurring in the Yellow Sea every winter.
Seasonal Variation of Volume Transport through the Straits of the East/Japan Sea Viewed from the Island Rule
Seung, Young Ho ; Han, Soo-Yeon ; Lim, Eun-Pyo ;
Ocean and Polar Research, volume 34, issue 4, 2012, Pages 403~411
DOI : 10.4217/OPR.2012.34.4.403
Among others, a question that has long been unanswered is why the seasonal variation of volume transport is larger in the Soya and Korea/Tsushima Straits than in the Tsugaru Strait. An attempt is made to answer this question in terms of the island rule with friction being taken into account. The problem is idealized as a simple model. The model results indicate that volume transport through a channel is determined not only by the circulation created around the adjacent island but also by those created around the neighboring islands farther away. The latter is due to the presence of bottom friction in the channels. The volume transports through the Korea/Tsushima, Tsugaru and Soya Straits estimated from the model using observed wind data show the general pattern of observed seasonality, although they contain large errors associated with the uncertain frictional parameter employed in the model. The model indicates that the observed seasonality arises essentially from the fact that wind stress curl changes its sign, from negative in the summer to positive in winter, following a large fluctuation of zero-stress curl latitude east of Hokkaido.
Prevailing Subsurface Chlorophyll Maximum (SCM) Layer in the East Sea and Its Relation to the Physico-Chemical Properties of Water Masses
Rho, TaeKeun ; Lee, Tongsup ; Kim, Guebuem ; Chang, Kyung-Il ; Na, TaeHee ; Kim, Kyung-Ryul ;
Ocean and Polar Research, volume 34, issue 4, 2012, Pages 413~430
DOI : 10.4217/OPR.2012.34.4.413
To understand the scales of the spatial distribution and temporal duration of the subsurface chlorophyll-a maximum (SCM) observed in the Ulleung Basin of the East Sea, we analyzed physical and chemical data collected during the East Asian Seas Time-series-I (EAST-I) program. The SCM layer occurred at several observation lines from the Korea Strait to
in the Ulleung Basin during August of 2008 and 2011. At each observation line, the SCM layer extended from the coast to about 200 km off the coast. The SCM layer was observed between 30 and 40 m depth in the Ulleung Basin as well as in the northwestern Japan Basin along
during July 2009, and was observed around 50 m depth in the northeastern Japan Basin (
) during July 2010. From these observed features, we hypothesize that the SCM layer observed in the Ulleung Basin may exist in most of the East Sea and may last for at least half-year (from the early May to late October). The nutrient supply mechanism for prolonged the SCM layer in the East Sea was not known, but it may be closely related to the horizontal advection of the nutrient rich and low oxygen waters observed in the Korea Strait between a 50 m depth to near the bottom. The prolonged development of the SCM layer in the Ulleung Basin may result in high primary production and would also be responsible for the high organic carbon content observed in the surface sediment of the region.
Numerical Experiment of Environmental Change in the East China Sea under Climate Change
Min, Hong Sik ; Kim, Cheol-Ho ;
Ocean and Polar Research, volume 34, issue 4, 2012, Pages 431~444
DOI : 10.4217/OPR.2012.34.4.431
We simulated and compared present and future ocean circulation in the East China Sea using an East Asia Regional Ocean model. Mean climate states for 1990~1999 and 2030~2039 were used as surface conditions for simulations of present and future ocean circulation, which were derived from the simulations of three different global climate models, ECHAM5-MPI, GFDL-CM2.0 and MIROC3.2_hires, for the 20th century and those of 21st century as projected by the IPCC SRES A1B. East Asia Regional Ocean model simulated the detailed patterns of temperature, salinity and current fields under present and future climate conditions and their changes instead of the simple structures of global climate models. To some extent, there are consistent ocean circulation changes derived from the three pairs corresponding to the global climate model in so much as the temperature increases not only in winter but summer at both the surface and bottom and that temperature and salinity changes are prominent near the Chinese coast and in the Changjiang bank. However, the simulated circulations are different among each other depending on the prescribed atmospheric conditions not only under present climate but also with regard to future climate conditions. There is not a coincident tendency in ocean circulation changes between present and future simulations derived from the three pairs. This suggests that more simulations with different pairs are needed.
Radical Scavenging Activity of Ethanol Extracts and Solvent Partitioned Fractions from Various Red Seaweeds
Cho, MyoungLae ; Lee, Dong-Jin ; You, SangGuan ;
Ocean and Polar Research, volume 34, issue 4, 2012, Pages 445~451
DOI : 10.4217/OPR.2012.34.4.445
The EtOH extracts of red seaweeds (Symphyocladia latiuscula, Chondrus ocellatus and Carpopeltis affinis) and solvent partitioned fractions were investigated for their 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS) and 1,1-diphenyl-1-picrylhydrazyl (DPPH) radical scavenging effects and the total phenolic contents were correlated with ABTS and DPPH radical scavenging activities. The EtOH extracts and their solvent partitioned fractions exhibited strong ABTS and DPPH radical scavenging activities. Among the solvent partitioned fractions obtained from n-Hexane (HX), methylenchloride (MC), ethylacetate (EA), and buthanol (BuOH), the HX fraction from C. affinis showed higher radical scavenging activities than other fractions. Total phenolic contents showed significant correlation (
= 0.709) with ABTS radical scavenging activity. The results of this study suggest that the strong radical scavenging activity of HX fraction from C. affinis is a promising natural antioxidant for healthcare products.
Effective Installation and Operating of High Frequency Ocean Surface Radars in Korea -Part 1: Hardware
Song, Kyu-Min ; Cho, Cheol-Ho ;
Ocean and Polar Research, volume 34, issue 4, 2012, Pages 453~462
DOI : 10.4217/OPR.2012.34.4.453
Ocean surface current data in Korea was collected using sets of High-Frequency Ocean Surface Radars (HFOSRs) with 25 radial sites in the frequency range of 5~43 MHz. Site selection and the correct installation of HFOSR are very important considerations in order to secure continuous and reliable results. The installation procedures of HFOSR are summarized as follows: 1. Survey area selection; 2. Investigation of ambient radio waves and installation environment; 3. Domestic license of radio station; 4. Installation of antenna and housing of electrical and communication devices. The current work describes the entire processes of HFOSR installation within Korea.