• Journal of Environmental Science International
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• v.5 no.4
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• pp.525-533
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• 1996

Chemical characteristics of the industrial wastewater sludge, degradation of the sludge in soil and CO2 generation and changes of nitrogen in soil treated with the sludge were investigated. The results obtained were summarized as follows: 1. Degradation rate of the sludge in soil was 26% at natural temperature, and 33% at incubation temperature at 12 weeks after treatment. 2. T-C, T-N and the C/N ratio of sludge in soil was 16.0%, 0.63% and 26, respectively, at natural temperature, and 15.0%, 0, 65% and 23, respectively, at incubation temperature at 12 weeks after treatment. 3, Camulative CO2 generation in soil treated with l%, 3% and 5% of sludge was 284, 440 and 512 mg/100 g, respectively, at natural temperature, and 440, 558 g and 654 mg/100g, respectively, at incubation temperature at 12 weeks after treatment. 4, Changes of :norganic nitrogen in soil treated with l%, 3% and 5% of sludge were 7.8, 12.8 and 16.3 mg/100g, respectively, at incubation temperature at 12 weeks after treatment. Mineralization ratio of organic nitrogen in soil treated with 1%, 3% and 5% of sludge was 10.7%, 13.6% and 15.2%, respectively, at incubation temperature at 12 weeks after treatment. 5. Chanties of pH in soil treated with 1%, 3% and 5% of Industrial wastewater sludge were in the range of 6.7~7, 5 at natural temperature, and 6.1~7.9 at incubation temperature at 12 weeks after treatment.

• The Korean Journal of Pesticide Science
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• v.8 no.3
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• pp.175-183
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• 2004

The characteristics of the experimental compound EK-5439 [3-Chloro-2-[4-chloro-2-fluoro-5-(5-methyl-3-phenyl-4,5-dihydroisoxazol-5-yl-methoxy)-phenyl]-4,5,6,7-tetrahydro-2H-indazole] was investigated to characterize as a new herbicide to use in rice field. The selectivity between rice and barnyardgrass was very good when treated from 0 to 4 days after seeding under soil application. In the overflowing experiment, herbicidal efficacy of EK-5439 was stabilized 12 hrs after application. Vertical migrations in submerged paddy soil of EK-5439 and oxadiazon were equally observed below a soil depth of 1 cm under 5 cm/day leaching condition. Half-lives for herbicidal efficacy of EK-5439 and oxadiazon were 6.1, and 9.6 days, respectively, under submerged paddy condition. EK-5439 showed rapid adsorption to the soil clay, such as bentonite.

• Geomechanics and Engineering
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• v.12 no.1
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• pp.111-125
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• 2017

Swelling and shrinkage characteristics of expansive fine grained soil cause volumetric changes followed by distress and damage to the structures. Soil stabilization can be explained as the alteration of the soil properties by chemical, mechanical or any other means in order to enhance the engineering properties of the soil. Utilization of industrial wastes in soil stabilization is cost effective and environment friendly. This paper presents an experimental study on stabilization of expansive soil using industrial wastes, viz. fly ash and dolochar. The paper includes the evaluation of engineering properties like unconfined compressive strength and California bearing ratio (CBR) of expansive soil collected from Balasore district of Odisha stabilized with fly ash and dolochar in different proportions and to predict the influence of these additives on engineering properties and strength characteristics of expansive soil. Both fly ash and dolochar were found to increase the CBR and decrease many index properties such as liquid limit, plastic limit, plasticity index, swelling index and UCS, thus enhancing the strength parameters of expansive soil.

• Journal of the Korean Institute of Landscape Architecture
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• v.33 no.6 s.113
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• pp.40-50
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• 2006

This study was carried out to examine the tree-ring growth characteristics of Zelkova serrata Makino after replanting, for the built-up planting founds for stability of landscaped trees in the reclaimed land from the sea. the factors, many affecting the growths of Zelkova serrata Makino, were the replanting stress and drought. The growth reduction due to replanting and drought occurred in the replanting year and the following year. The mean sensitivity(year-to-year variation) and the coefficient of variation(tree-to-tree variation in a certain year) in tree rings of Zelkova serrate Makino, were higher in the poor soil sites than in the favourable soil ones. And the poor soil sites were the filled ground of improve soil and the covered ground of improve soil and the top ground of big mounding than mounding ground sites, especially soil hardness, alkali soil, high $Na^+\;and\;K^+,\;low\;Ca^{++}\;and\;Mg^{++}$ and T-C were the most crucial. We suggest technique development of the built-up planting ground for stability in the reclaimed land from the sea. The built-up planting grounds in reclaimed land from the sea, should be considered for the use of fair soil with the physical and chemical soil properties, -high level foundation of planting ground, and the prevention of disturbed soil-.

• Proceedings of the Korean Geotechical Society Conference
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• 2000.11a
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• pp.657-664
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• 2000

Weak and soft compressible clay deposits are commonly found in natural subgrade soils. These Soils need to be stabilized for using the subbase materials of highway constructions. This paper presents that a chemical treatment using chemical additives comprised of sulfate(SO$_4$) and chloride(Cl) is evaluated for stabilizing soft clay deposits and lime. The physical and mechanical characteristics of soil-lime and additives are described by means of a laboratory study. The study results indicate that the presence of chlorides encouraged the efficiency of lime stabilization, and the use of calcium chloride with quicklime is the best additive for improving soil behavior. The treated soil with lime-calcium chloride can have the adaptability to the subbase materials of highway constructions.

• Korean Journal of Soil Science and Fertilizer
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• v.48 no.4
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• pp.262-270
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• 2015

The scientific information between microbial community and chemical properties of reclaimed tidal soil is not enough to understand the land reclamation process. This study was conducted to investigate the relation between chemical properties and microbial activities of soils from reclaimed tidal lands located at south-western coastal area (42 samples from Goheuong, Samsan, Bojun, Kunnae, Hwaong and Yeongsangang sites). Most of the reclaimed soils showed chemical characteristics as salinity soil based on EC. Only $Na^+$ in exchangeable cation was dependent on EC of reclaimed soil, whereas other cations such as $K^+$, $Ca^{2+}$, and $Mg^{2+}$ were independent on EC. The mesophilic bacteria decreased with an increase in EC of soil. Microbial population increased with soil organic content in the range of $0{\sim}10g\;kg^{-1}$ and dehydrogenase activity less than $100{\mu}g-TPF\;g^{-1}h^{-1}$. Microbial population of soils from reclaimed tidal lands was closely related to the microbial community containing hydrolytic enzyme activities of cellulase, amylase, protease, and lipase.

• The Journal of Engineering Geology
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• v.31 no.4
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• pp.731-739
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• 2021

This research aimed to analyze the characteristics of topsoil for soil conservation and promote the process of turning subsoil into topsoil. The physicochemical characteristics of topsoil and subsoil of different types of soil were compared, and their quantitative differences were examined. 204 soil samples were collected from a total of 102 areas according to rock types. These samples were tested to measure grain size, water content, and unit weight, along with XRF and XRD analyses. The topsoil and subsoil of the soil samples were also analyzed. The results of this research showed that the topsoil and subsoil had different physical characteristics, and that the chemical alteration index of the topsoil was higher than that of the subsoil. This would imply that the topsoil was high in clay minerals since it was directly affected by weathering more than the subsoil. In particular, vermiculite, one of the final products generated from weathering, was common in the topsoil.

• The Journal of Engineering Geology
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• v.27 no.4
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• pp.451-462
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• 2017

Physical weathering caused by external forces and chemical weathering caused by the decomposition or alteration of constituent materials are the two factors that dominate the mechanical properties of rocks. In this study, a field investigation was undertaken to identify the physical and chemical weathering characteristics of the biotite granite and granitic weathered soils in Gyeongju, South Korea. Samples were collected according to their grade of weathering and subjected to modal analysis, XRD analysis, XRF analysis, physical property tests, particle size distribution tests, and slake durability tests. Modal and XRD analysis identified these rocks as biotite granite; secondary alteration minerals were not observed. Physical property tests and particle size distribution analyses indicate an average porosity of 41.28% and a sand content of > 90 wt.%. These values are somewhat higher than those of granites in general. The results of the slake durability test and XRF analyses show that the physical and chemical weathering indices of the samples vary with the degree of weathering.

• Journal of The Korean Society of Grassland and Forage Science
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• v.24 no.3
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• pp.237-244
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• 2004

This experiment was carried out to determine the growth characteristics, dry matter and TDN yield of corn for silage (Zea mays L.), soil nitrate in infiltration water by chemical fertilizer and different manure application(C; chemical fertilizer + chemical fertilizer, T1; Lime +chemical fertilizer + chemical fertilizer, T2; swine manure + swine manure, T3; Lime + swine manure + swine manure, T4; swine manure +chemical fertilizer). The results obtained are summarizes as follows; The mean growth characteristics of T3 treatment(soil treatment: lime + base fertilizer: liquid manure + additional fertilizer: chemical fertilizer) was higher than those of other treatments. The highest yield of dry matter and TDN was obtained in T3 treatment with 18,611 and 13,746 kg/ha, respectively(P<0.05), and the lowest in T1 treatment with 13,529 and 9,541 kg/ha, respectively(P<0.05). The contents of NDF and ADF were not significant different among treatments. However, NDF and ADF content among treatments were the highest with T1 treatment and the lowest with T3 treatment. $NO_3$ level of soil was hardly influenced by the different manure application treatment, and not affected during the experiment time.

• Journal of environmental and Sanitary engineering
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• v.17 no.1
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• pp.52-56
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• 2002

The study was carried out to evaluate the characteristics of biodegradation by Pseudomonas putida G7 in soil column. The reactor system was used to investigate mass transfer of VOCs as Toluene in a column of unsaturated soil. Determination of the fate of VOCs in unsaturated soil is necessary to evaluate the feasibility of natural attenuation as a VOCs remediation strategy. The objective of this study was to develop a mechanistically based mathematical model that would consider the interdependence of VOC transport, microbial activity, and sorptive interactions in a moist, unsaturated soil. Because the focus of the model was on description of natural attenuation, the advective VOCs transport that is induced in engineered remediation processes such as vapor extraction was not considered. It can be concluded that the coefficient for gas liquid mass-transfer was found to be a key parameter controlling the ability of bacteria to VOCs. Finally, it appeared that bioremediation technology of VOCs which are difficult to be decomposed by chemical methods.