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71.
Ji-Yeon Park Sang-Joon Kim You-Jin Lee Kitae Baek Ji-Won Yang 《Engineering Geology》2005,77(3-4):217-224
Feasibility of electrokinetic (EK) process combined with Fenton-like reaction was investigated for the removal of phenanthrene in a two-dimensional cell. Sandy soil and bentonite were selected as a model soil and a filling material to inhibit the leak of electrolyte solution within the electrode reservoirs into the soil by hydraulic pressure difference, respectively. The effects of parameters including current, electroosmotic flow (EOF), electrolyte pH, and moisture content on the removal efficiency were examined under constant voltage.
At the end of operation for 21 days, the concentration of phenanthrene near the anode was lower than the other positions of soil specimen and increased gradually towards the cathode because hydrogen peroxide solution was supplied from anode to cathode region following the direction of EOF. The concentration of phenanthrene at the bottom soil was lower than that at the top soil. Because capillary attraction in the sandy soil with high porosity was too low to maintain appropriate moisture at the top of the cell, EOF moved through the bottom soil with higher moisture content. Overall removal efficiency at 140 V was 81.6%, which was higher than 68.9% at 100 V because total EOF increased by a factor of 1.5 upon increase of the voltage from 100 to 140 V. In addition, power consumptions at 100 and 140 V were 7.2 and 19.4 kWh, respectively. 相似文献
72.
Sangho Baek Oh-Ig Kwoun Braun A. Zhong Lu Shum C.K. 《Geoscience and Remote Sensing Letters, IEEE》2005,2(4):413-417
We present a digital elevation model (DEM) of King Edward VII Peninsula, Sulzberger Bay, West Antarctica, developed using 12 European Remote Sensing (ERS) synthetic aperture radar (SAR) scenes and 24 Ice, Cloud, and land Elevation Satellite (ICESat) laser altimetry profiles. We employ differential interferograms from the ERS tandem mission SAR scenes acquired in the austral fall of 1996, and four selected ICESat laser altimetry profiles acquired in the austral fall of 2004, as ground control points (GCPs) to construct an improved geocentric 60-m resolution DEM over the grounded ice region. We then extend the DEM to include two ice shelves using ICESat profiles via Kriging. Twenty additional ICESat profiles acquired in 2003-2004 are used to assess the accuracy of the DEM. After accounting for radar penetration depth and predicted surface changes, including effects due to ice mass balance, solid Earth tides, and glacial isostatic adjustment, in part to account for the eight-year data acquisition discrepancy, the resulting difference between the DEM and ICESat profiles is -0.57/spl plusmn/5.88 m. After removing the discrepancy between the DEM and ICESat profiles for a final combined DEM using a bicubic spline, the overall difference is 0.05/spl plusmn/1.35 m. 相似文献
73.
Dongseon Kim Eun-Jin Yang Seung Ho Baek Kyung-Hee Kim Jin-Hyun Jeong Young-Ok Kim 《Ocean Science Journal》2014,49(3):223-230
Dissolved inorganic carbon (DIC) and alkalinity were precisely measured for surface and bottom waters in Gwangyang Bay, Korea, during the four seasons to assess seasonal variations of aragonite saturation state (Ωarag). Both the surface and bottom waters were undersaturated with respect to aragonite during summer but were supersaturated during the other seasons. The summertime undersaturation of the surface waters with respect to aragonite may have been a result of the dilution effect caused by higher seasonal river runoff. In the bottom waters, the average DIC concentration increased by 40.6 μmol kg?1 from spring to summer, while the average alkalinity decreased by 74.7 μeq kg?1. As a result, the alkalinity/DIC ratio decreased from 1.07 in spring to 1.01 in summer and pH also decreased from 7.91 to 7.48, which resulted in the summertime undersaturation of the bottom waters. 相似文献
74.
Gyoung-Man Kim Dae-Hoon Kim Jung-Seock Kang Hwanjo Baek 《Environmental Earth Sciences》2014,71(10):4603-4609
Spent mushroom compost (SMC) is commonly used as a carbon source for passive treatment systems in South Korea; however, it has some drawbacks, such as sulfate release from itself. Consequently, investigations to identify effective substitutes for SMC are necessary. In this study, batch experiments were conducted for 27 days to evaluate the efficiency of rice wine waste (RWW) for reducing sulfate and removing dissolved metals within synthetic acid mine drainage (AMD). The results showed that RWW could be more suitable than SMC, which even released sulfate in the early stage of the experiment, for sulfate reduction by sulfate-reducing bacteria. Both materials produced similar results with respect to the removal of dissolved metals, such as Fe and Al. Furthermore, a mixture of SMC and RWW showed the greatest efficiency in sulfate removal. Overall, both RWW and the mixed carbon source showed comparable performance to SMC, which indicated that RWW had a great potential for use as a carbon source for AMD treatment. 相似文献
75.
Lee Jong-Seok Baek Ji-Yeon Jung Dawoon Shim Jae-Seol Lim Hak-Soo Jo Young-Heon 《Ocean Science Journal》2019,54(3):349-362
Ocean Science Journal - Observing coastal water depths is very important to understand physical processes of the coastal environment and manage coastal resources. In this study, a low-altitude... 相似文献
76.
Sangil Kim Suk Hyun Youn Hyun-Ju Oh Sun Kyeong Choi Yun Hee Kang Tae-Hoon Kim Hyuk Je Lee Kwang-Sik Choi Sang Rul Park 《Ocean Science Journal》2018,53(3):595-600
We conducted testing to determine whether stipe length is a useful indicator of reproductive maturity in the kelp Ecklonia cava, a species that plays a pivotal role in ecosystem functioning and services in subtidal areas. Approximately 100 sporophytes with stipes of various lengths were collected during the fertile period (July–November, 2013). We investigated the relationships between stipe length and other morphological characteristics to determine whether stipe length could indicate the age of reproductive maturity. Primary blade length, longest blade length, thallus height, and total length showed significant relationships with stipe length. The length of the primary and longest blades gradually declined as stipe length increased above 125 mm. Zoosporangial sori were found on the blades of more than 70% of individuals with stipes longer than 125 mm, but on only 8% of individuals with stipes less than 125 mm long. Stipe length therefore seems to be an acceptable proxy for reproductive maturity. Another factor to consider, however, is that all specimens with zoosporangial sori, regardless of stipe length, had a dry weight of 80 g or more; thus, individual biomass may also be an important parameter influencing the initiation of reproduction. 相似文献