• Journal of Animal Environmental Science
• /
• v.2 no.1
• /
• pp.63-78
• /
• 1996

The main purpose of this research project is to monitor the present state of agricultural environment and to develope the countermeasures for the protection of the environment from the pollution by animal wastes. The results of this research were described largely 3 parts, 1) Monitoring of present state of environmental pollution by animal wastes, 2) Monitoring of animal wastes treatment technology, 3) Strategies for the protection of environmental pollution from animal wastes in future. The current most important problems from animal wastes are water pollution and air pollution commonly regardless of domestic or foreign country. Especially, intensive livestocks breeding pattern in restricted area is actually a real reason of eutrophication, soil acidification, ground water contamination, irrigation water pollution. As a result from this research project, authors recommend the 3 type of strategies for the protection of environmental pollution by animal wastes, 1 . Development of non-discharge type of wastes treatment technology 2. Manufacturing local structure for animal waste recycling system 3. Development of new international environmental program for transfer bioresource and soil environment prevention.

• Journal of the Korean Chemical Society
• /
• v.66 no.4
• /
• pp.269-277
• /
• 2022

In recent years, carbon-based catalysts have become a research hotspot in environmental governance applications. Carbon-based catalysts have large surface areas, porous structures, multi-surface functional groups and excellent electron transfer capabilities, and can synergistically exhibit adsorption and catalytic performance. This article reviews the research progress of carbon-based catalysts in environmental governance, mainly including its application in wastewater treatment, exhaust gas purification and soil remediation. In view of the current difficulties in the research of carbon-based catalysts, the development prospects are proposed. We hope that this review will provide convenience for new entrants and researchers intending to employ carbon-based catalysts for the remediation of contaminated environment.

• Structural Engineering and Mechanics
• /
• v.84 no.4
• /
• pp.465-477
• /
• 2022

The formation of biopolymer-soil matrices mainly depends on biopolymer type and concentration, soil type, pore fluid and phase transfer to influence its strengthening efficiency. In this study, the physical and mechanical properties of sodium alginate (SA) treated kaolinite are investigated through compaction test, thread rolling teat, fall cone test and unconfined compression test with considering biopolymer concentration, curing time, initial water content, mixing method. The results show that the liquid limit slightly decreases from 69.9% to 68.3% at 0.2% SA and then gradually increases to 98.3% at 5% SA. At hydrated condition, the unconfined compressive strength (UCS) of SA treated clay at 0.5%, 1%, 2% and 3% concentrations is 2.57, 4.5, 7.1 and 5.48 times of untreated clay (15.7 kPa) at the same initial water content. In addition, the optimum biopolymer concentration, curing time, mixing method and initial water content can be regarded as 2%, 28 days, room temperature water-dry mixing (RD), 50%-55% to achieve the maximum unconfined compressive strength, which corresponds to the UCS increment of 593%, compared to the maximum UCS of untreated clay (780 kPa).

• Journal of Nuclear Fuel Cycle and Waste Technology(JNFCWT)
• /
• v.4 no.4
• /
• pp.365-372
• /
• 2006

A dynamic compartment model is presented to predict the contamination level of agricultural plant by $^{137}C_s$ as a result of a soil deposition. The model considered the processes of a percolation, soil mixing by a plowing before transplanting, plant uptake, leaching to a deep soil, and fixation to a clay mineral. The effects of the soil properties (pH, clay mineral, organic matter content, and exchangeable K), which are spatially varied, on a plant uptake and the leaching rates of $^{137}C_s$ in a root zone soil were modeled by the Absalom model. To test the validity of the model, the $^{137}C_s$ aggregated transfer factors(TFa) for rice plants were compared with those observed from some simulated $^{137}C_s$ soil deposition experiments, which were carried out with respect to rice plants cultivated in seventeen paddy soils of different properties for two consecutive years. Observed $^{137}C_s$ TFa values of the rice plants did not show an evident trend for the pH and clay content of the soil properties, while they increased with an increasing organic matter content or a decreasing exchangeable K concentration. Predicted $^{137}C_s$ TFa values of the rice plants were found to be comparable with those observed.

• Journal of the Korean Society of Tobacco Science
• /
• v.32 no.1
• /
• pp.28-34
• /
• 2010

Tobacco plants absorb cadmium from soil and accumulate it in high concentrations in their leaves. Additionally, a significant portion of the cadmium contained in cigarettes passes into the smoke. Cadmium is known to be a toxic and carcinogenic compound that has harmful effects on the human body due to smoking. In this study, the concentrations of cadmium in the Ky3R4F reference cigarette and two commercial cigarettes were analyzed by inductively coupled plasma mass spectrometry. Each cigarette sample was partitioned into a tobacco rod and filter and then analyzed in order to determine the concentration of cadmium. The concentrations of cadmium in the mainstream smoke, ash, residue, and cigarette butt were also analyzed after the cigarettes were smoked under ISO smoking conditions. Transfer rates of the cadmium from the tobacco rod to the mainstream smoke, ash, and cigarette butt were 0.8 ~ 5%, 17 ~ 22%, and 5 ~ 7%, respectively. As a result, we estimated that the sidestream smoke contained about 70% of the cadmium from the tobacco rod.

• Journal of Ecology and Environment
• /
• v.38 no.2
• /
• pp.123-131
• /
• 2015

During several visits to the Cebu City landfill in the Philippines, plants were observed growing within the area, including on top of the garbage piles. Studying the response of these plants is important in assessing which can be used in remediating metal contaminated soils. This study aimed to determine whether the plants in the Cebu City landfill excluded or accumulated cadmium (Cd) and chromium (Cr) in the plant tissues. The floristic composition of the landfill was analyzed prior to the sample collection. The samples were acid-digested before the desired elements were measured using atomic absorption spectrophotometry (AAS). The Cd and Cr concentrations in the plant root-zone soil were also measured using AAS. The results indicated that the landfill substrate was generally acidic based on the results of the pH measurement. Of the 32 plant species sampled, Cyperus odoratus showed potential for Cd uptake and internal transfer; Cenchrus echinatus, Vernonia cinerea and Terminalia catappa for Cr uptake, and Cynodon dactylon for Cr internal transfer. The plants in the landfill differed in their response towards the heavy metals. To confirm the behavior of C. odoratus towards Cd, and C. echinatus, C. dactylon, V. cinerea, and T. catappa towards Cr, controlled experiments are recommended, as the plant samples analyzed were collected from the field.

• Journal of the Korean Society for Geothermal and Hydrothermal Energy
• /
• v.7 no.2
• /
• pp.43-50
• /
• 2011

This paper presents how to analyze heat transfer characteristics of double-layered soils. Thermal response tests were conducted to measure the ground thermal conductivities of Joomunjin sand and double layered soils filled in a steel box of which the size is $5m{\times}1m{\times}1m$. Double-layered soils were composed of Joomunjin sand and Kaoline clay. Each thermal conductivity of Joomunjin sand and Kaloine clay was measured by using Heat Flow Meter considering different void ratio. The ground thermal conductivity of double-layered soils was 15% smaller than that of Joomunjin sand.

• Geomechanics and Engineering
• /
• v.30 no.1
• /
• pp.1-10
• /
• 2022

Seismic ground response evaluation is one of the main issues in geotechnical earthquake engineering. These analyses are subsequently divided into one-, two- and three-dimensional methods, and each of which can perform in time or frequency domain. In this study, a novel approach is proposed to assess the seismic site response using two-dimensional transfer functions in frequency domain analysis. Using the proposed formulation, a program is written in MATLAB environment and then promoted utilizing the equivalent linear approach. The accuracy of the written program is evaluated by comparing the obtained results with those of actual recorded data in the Gilroy region during Loma Prieta (1989) and Coyote Lake (1979) earthquakes. In order to precise comparison, acceleration time histories, Fourier amplitude spectra and acceleration response spectra diagrams of calculated and recorded data are presented. The proposed 2D transfer function diagrams are also obtained using mentioned earthquakes which show the amount of amplification or attenuation of the input motion at different frequencies while passing through the soil layer. The results of the proposed method confirm its accuracy and efficiency to evaluate ground motion during earthquakes using two-dimensional model. Then, studies on irregular topographies are carried out, and diagrams of amplification factors are shown.

• Proceedings of the Korean Society of Soil and Groundwater Environment Conference
• /
• 2001.09a
• /
• pp.27-30
• /
• 2001

Flow and transport at fracture intersections, and their effects on network scale transport, are investigated in three-dimensional random fracture networks. Fracture intersection mixing rules complete mixing and streamline routing are defined in terms of fluxes normal to the intersection line between two fractures. By analyzing flow statistics and particle transfer probabilities distributed along fracture intersections, it is shown that for various network structures with power law size distributions of fractures, the choice of intersection mixing rule makes comparatively little difference in the overall simulated solute migration patterns. The occurrence and effects of local flows around an intersection (local flow cells) are emphasized. Transport simulations at fracture intersections indicate that local flow circulations can arise from variability within the hydraulic head distribution along intersections, and from the internal no flow condition along fracture boundaries. These local flow cells act as an effective mechanism to enhance the nondiffusive breakthrough tailing often observed in discrete fracture networks. It is shown that such non-Fickian (anomalous) solute transport can be accounted for by considering only advective transport, in the framework of a continuous time random walk model. To clarify the effect of forest environmental changes (forest type difference and clearcut) on water storage capacity in soil and stream flow, watershed had been investigated.

• Proceedings of the Korean Geotechical Society Conference
• /
• 2006.03a
• /
• pp.1287-1294
• /
• 2006

A pile is compressed with settlements when loading and bearing capacity is altered along relative displacement of pile/soil on settlement and compression. Settlements of pile displaying limit skin friction is different from displaying tip resistance. Therefore, it is an error in traditional method that bearing capacity of pile is estimated from the sum of limit skin fraction and tip resistance. Accordingly, development of design method considering behavior of load-settlement is needed. In this study, we would like to establish the base for development of design method considering bearing capacity altering along displacement on settlement and compression. For this, we established system and substance of design method. And in order to establish relationship of load-settlement of pile on the type of soil, we analyzed and arranged existing database and pile loading test. On design method, settlement is assumed gradually on each capacity level being assumed gradually. Bearing capacity developing on the pile is obtained on each settlement level. Until the obtained bearing capacity will be equal to assumed capacity, this process is continued with increasing settlement. Load-settlement curve for soil classification is sketched in the process computing settlement on assumed capacity. This design method will be materialized by computation program.