• Preventive Nutrition and Food Science
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• v.12 no.1
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• pp.35-39
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• 2007

This study was conducted to investigate the effects of soil selenium (Se) supplementation level on Se contents of green tea and milk vetch. Four different concentrations of sodium selenite ($Na_2SeO_3$) solutions (0.0, 3.3, 33.0 and 165.0${\mu}g/mL$) were prepared and one liter of each solution was well mixed with 10 kg of compost (cowpea soil) to give four different levels of Se-containing soil: $T_1$, 0; $T_2$, 33; $T_3$, 330; $T_4$, and 1,650${\mu}g$/100 g soil. Green tea plants and milk vetch were individually cultivated in those soils for 60 days. Se contents of freeze-dried green tea leaves were 6.87, 10.40, 12.04, and 20.19 ${\mu}g/g$, respectively; all of which were significantly different (p<0.05) from the others except for $T_2$ and $T_3$. The results showed that Se-contents of green tea leaves were increased 1.5$\sim$2.9 times as the Se level in the soil increased. Regression equation between Se contents in green tea (Y) and soil Se supplementation level (X) was: Y=0.007X＋8.857. However, Se contents in the milk vetch were increased significantly (p<0.05) more with the same treatments $T_3$ (74 ${\mu}g/g$) and $T_4$ (187$\mu$g/g) in comparison to those at $T_1$ (5.0 ${\mu}g/g$) and $T_2$ (12.0$\mu$g/g). The increases ranged from approximately between 2.4 to 37.4 times that of the control group. Regression equation between Se contents in milk vetch (Y) and soil Se supplementation level (X) was: Y=0.1063X＋15.989. The large difference of Se contents between green tea leaves and milk vetch would be attributed by the difference of protein contents between the 30% or higher protein-content of legumes and 15$\sim$20% protein of shrubs. The present study clearly indicates that green tea leaves and milk vetch can be enriched in selenium by supplementing the soil with Se. Therefore, Se-enriched green tea or milk vetch powder could be utilized as functional foods in Se-fortified green tea drinks or salads, or as food additives to enhance the daily intake of Se.

• Journal of Korean Society of Environmental Engineers
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• v.32 no.12
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• pp.1076-1086
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• 2010

Soil remediation technologies were experimented to evaluate whether the technologies could be used to apply remediation of contaminated marine sediment. In this research, marine sediments were sampled at "Ulsan" and "Jinhae" where remediation projects are considered, and then the possibility of heavy metal removal was evaluated throughout the technologies. Heavy metal concentration of silt and clay fraction was higher than that of sand fraction at "Ulsan". Heavy metal removal of the silt and clay fraction was arsenic (As) 81.5%, mercury (Hg) 93.8% by particle separation, cadmium (Cd) 72.2%, mercury (Hg) 93.8% by soil washing technology, cadmium (Cd) 70.8%, lead (Pb) 65.6% by another soil washing technology. Based on experimental results, tested particle separation and soil washing technologies could be used to remove heavy metals of sand fraction and silt and clay fraction. Heavy metal removal by soil washing technology which was composed of separation, washing and physical or chemical reaction by additives such as acid, organic solvents was more effective comparing to that of particle separation. Since heavy metal concentration of all treated samples was suitable for national soil standards, all the tested technologies were could be used not only to remove heavy metals of marine contaminated sediment but also to reuse treated samples in land.

• Journal of Soil and Groundwater Environment
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• v.7 no.2
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• pp.3-11
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• 2002

The objective of this study was to survey the oil contamination around the Mountain Baegun at Uiwang city to obtain the preliminary data for bioremediation. For measuring the oil concentrations and physical properties from soil, we analyzed BTEX. TPH and pH, organic content, water content, pormeability coefficient, gravity, porosity and used the purge & trap method for analyzing BTEX. Using the Accelerated Solvent Extractor, we pretreated the samples and then analyzed TPH using GC-FID as soon as possible. From the analysis results, maximum concentration of TPH was 24.773mg/kg and BTEX was 101.7mg/kg. The results of TPH at the Mountain Baegun were higher than the enforcement standard of soil contamination(Korea) and the BTEX concentrations were also higher than the advisory standard of soil contamination(Korea). From these results, the Mountain Baegun may requires to remedy the oil-contaminated soil. In addition, we performed the field bioremediation test for five weeks at the Mountain Baegun using the microbial additives that were developed by our laboratory. From the results of the field test, we could find the about 95% of the oil was removed from the contaminated soil in five weeks. So we consider that it is the one of the useful solutions to remedy the oil-polluted site.

• Journal of the Korean Society of Environmental Restoration Technology
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• v.5 no.4
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• pp.1-9
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• 2002

This study is carried out to make the environmentally affinitive porous planting block for revegetation and to make a effective program for greening plans. The summary is shown below. 1. In order to get stronger intensity and distribute proper porosity in the block for planting, the cements mixed with fine soil were used and the finer in soil grains gives the stronger in intensity of the cements. Use of the furnace slag cements instead of the portland cements showed relatively stronger in intensity of the block. The intensity of the block became stronger when the mixed ratio of the cements to soil is 5 : 1, but the pore space ratio was lower. The percolate pH of the portland cements after one month of treatment was 13.1 but the percolate pH of the furnace slag cements was shown lower. To mold proper porous planting blocks, the proper combination of additives such as the dehydrating agent, elastic agent and adhesives into the mixture of cements and soil gives better effectives. 2. After molding the porous planting blocks, it gave a better result when the grains of the filler made of peat moss, upland soil and compound fertilizer were smaller than 2 mm in size. Shaking of the filling materials also gave the better result, but it took more time and cost much more. Therefore, it was better when the filling materials were mixed with water first then flew down for stuffing. 3. It was necessary to cover with soil after seeding or planting on the porous planting blocks. The proper thickness of the soil to help root development and keep moisture is about 3~5 cm. 4. The plants for planting on the porous planting block were required stronger in the growth condition of their roots and their environmental adaptability. The average germination percentage and rate of Platycodon grandiflorum on the porous planting block were 88.8% and 85% accordingly and their rate is very uniform. The germination rates of Dianthus superbus var. longicalycinus and Taraxacum officinale were more than 50%. These grass species, Chelidonium majus var. asiaticum, Lysimachia mauritiana and Scabiosa mansenensis were the suggested biennial grasses in the planting area where exchanging of the seedling or nursery plants was not necessary because their germination rates were 59.3, 45.6 and 40.3% accordingly. Viola kapsanensis, Chrysanthemum sp., Taraxacum sp. and Iris ensata var. spontanea are the grass species that could be used by seeding for greening. However, the germination rate of Solidago virga-aurea var. asiatica, Aster scaber and Lythrum anceps were lower than 10%. The coverage ratio of Ixeris stolonifera is more than 80% after 60 days seeding and the root length of most of species are more than 10 cm except Iris ensata var. spontanea and Platycodon grandiflorum because their root developed thicker than other species.

• Economic and Environmental Geology
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• v.52 no.1
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• pp.29-35
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• 2019

The purpose of this study was to assess the applicability of acid mine drainage sludge (AMDS) pellets for the arsenic (As) stabilization and to suggest an evaluation method for arsenic stabilization efficiency in soil around abandoned coal mines. The soil samples were collected from the agricultural field around Ham-Tae, Dong-Won, Dong-Hae, and Ok-Dong coal mine. The As concentration in soil was exceeding the criteria of soil pollution level, except for Ham-Tae coal mine. The AMDS pellets are more appropriate to use by reducing dust occurrence during the transport and application process than AMDS powder. In addition, AMDS pellets were maintained the As stabilization efficiency. The application of AMDS pellets for the As stabilization in soil was assessed by column experiments. The AMDS pellets were more effective than limestone and steel slag, which used as the conventional additives for the stabilization process. The As extraction by $0.43M\;HNO_3$ or $1M\;NaH_2PO_4$ solution were appropriate evaluation methods for evaluation of As stabilization efficiency in the soil.

• Journal of Korean Tunnelling and Underground Space Association
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• v.25 no.2
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• pp.65-85
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• 2023

The use of TBM (Tunnel boring machine) has increased worldwide due to its performance together with the benefit of being safely and environmentally friendly compared to conventional tunneling. In particular, EPB (Earth Pressure Balanced) TBM is widely used because it can be applied to various grounds compared to Open TBM. Also EPB TBM has a simple mechanical structure and advantages in cost, requires less ground area than Slurry TBM. EPB TBM has advantages in soft ground, and more importantly, can extend its applicability by use of appropriate soil conditioning, which improves mechanical and hydrological properties of excavated soil and increases the excavation performance of EPB TBM. Various studies suggested the proper mixing ratio and injection ratio, but almost they are limited to laboratory test under atmospheric pressure such as slump test. Actual field conditions may differ depending on the ground and mechanical condition. In this study, first the amount of used soil conditioning used in the field with various grounds from hard rock to soft ground was estimated through laboratory tests and compared with the estimate in design stage. And also it was compared with the amount used during actual excavation. In addition, experience of soil conditioning for the problems of cutter head clogging and groundwater inrush that occurred during excavation is discussed. Finally, lesson learned for the use of soil conditioning in difficult ground condition such as mixed ground are reviewed.

• Microbiology and Biotechnology Letters
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• v.23 no.1
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• pp.43-46
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• 1995

For using additives of foods, or cosmetics, a strain A80 producing blue pigment was isolated from soil. The strain A80 was identified as a strain of Azotobacter vinelandii based on morphological and physiological characteristics. The strain A80 was extracellulaly secreted the blue pigment on PYG agar plate, but not secreted it into PYG broth. And then, the strain A80 was extracellulaly secreted the blue pigment in PYG broth containing 2.0% chitin, while the strain A80 was not secreted the blue pigment in PYG broth containing 2.0% chitin and 1% NaCl simultaniously.

• Toxicological Research
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• v.32 no.1
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• pp.65-72
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• 2016

Man-made cadmium (Cd) emissions can be transported between environmental matrices and the food chain. Food is the primary source of Cd exposure among general population as a consequence of the bioconcentration of Cd from soil. Chronic Cd exposure has been reported to be associated with chronic kidney disease, osteoporosis, diabetes, cardiovascular disease and cancer. The Joint FAO/WHO Expert Committee on Food Additives (JECFA) established the safe level of Cd intake as provisional tolerable monthly intake (PTMI) of $25{\mu}g/kg\;bw$ in 2010. The major food groups that contribute to the most Cd exposure are rice and grains, shellfish and sea food, meat including edible offal, and vegetables. A number of studies reported the high Cd contaminated levels in foods from polluted areas in Thailand. The results are of high concern since the contaminations occur in foods that are major Cd contributors. Thus, in this review, the current situations of Cd contaminated foods in polluted areas of Thailand are summarized. In addition, the Cd intakes from selected scenarios are estimated to assess the potential health risk to consumers and the suggestions are also included.

• Journal of the Korean Geotechnical Society
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• v.17 no.4
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• pp.145-151
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• 2001

본 연구에서는 울산 삼산지역의 도시 개발로 인하여 다량 발생되고 있는 건설잔토의 유효이용을 목적으로 대상토에 생석회와 화학 첨가제를 혼합하여 안정처리를 할 경우 보조기층 및 노상용 재료로써의 사용 가능성을 평가하였다. 1가 이온($Na^{+}$, $K^{+}$)가 2가 이온(Ca$^{2+}$, $Mg^{2+}$), 염화물(Cl)과 황산염(So$_4$)으로 구성된 화학 첨가제의 첨가에 따른 일축압축강도를 비교한 결과, 1가 이온의 첨가시 장기강도 발현이 우수한 것으로 나타났고, 염화물(Cl)은 첨가시 강도 발현이 우수한 것으로 나타났다. 건설잔토에 생석회와 CaCl$_2$를 첨가하면, 생석회로 처리된 시료에 비해 2배~4배의 강도가 증가되어 생석회 안정화에 대한 효과가 좋은 것으로 나타났다. 원시료토에 생석회, 생석회와 화학 첨가제로 안정처리하여 도로의 보조기층재료나 노상용 재료로의 사용여부를 평가한 결과, 생석회와 CaCl$_2$로 안정처리한 경우만이 시방기준 CBR 10%이상, 소성지수 10%이하를 만족시켜 노상용 재료로서의 사용가능성을 확인할 수 있었다.

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
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• v.2 no.2
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• pp.145-153
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• 2004

H$_2$SO$_4$ and citric acid were used as additives for the electrokinetic remediation experiment to increase removal efficiency of $^{137}$ Cs and $^{60}$ Co from the radioactive soil waste stored for more than 10 years. The average effluent velocity discharged from the elctrokinectic remediation experimental column was 2.0${\times}$10$^{-2}$ cm/min and the discharged soil wastewater volume for 10 days is 3.6 pore volume of the column. 97% of $^{60}$ Co in the column was decontaminated for 10 days of operation, while only 54% of $^{137}$ Cs was decontaminated. These results are considered that the absorption equilibrium coefficient of $^{137}$ Cs is higher than that of $^{60}$ Co. The predicted values of the residual concentration by the proposed mathematical model were well coincided with the experimental results within the experimental error range