• International Journal of Industrial Entomology and Biomaterials
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• v.17 no.2
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• pp.169-172
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• 2008

Indian tropical tasar silkworm, Antheraea mylitta D is reported to have forty four ecoraces by way of their adoption to different topographical and vegetational conditions. Of late, another ecorace 'JATA' - univoltine under in-situ condition has been explored which is localized in Thakurmunda area of the foot hills of Simlipal biosphere (Mayurbhanj district) of Orissa, India. The ecorace 'Jata' exhibits superior economic characters over widely commercialized ecoraces of Daba and Sukinda. The cocoon production of localized 'Jata' ecorace is depleting day by day in in-situ condition. In the present study, efforts were made to stabilize the ecorace 'Jata' under ex-situ condition at Ranchi (Jharkhand), where the 'Jata' ecorace silkworms were reared on Terminalia tomentosa for four successive generations during 2006 and 2007 and the cocoons were preserved in grainage house under prevailing climatic conditions. The results indicated change in voltinism behaviour of the 'Jata' ecorace from univoltine to bivoltine. The rearing performance and grainage efficiencies indicate the tendency of 'Jata' ecorace towards acclimatization and stabilization under Ranchi climatic conditions. The 'Jata' ecorace manifests the prospects for acclimatization, stabilization and commercial exploitation.

• Journal of The Korean Society of Agricultural Engineers
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• v.50 no.5
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• pp.73-81
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• 2008

This study evaluated the applicability of in-situ concrete pile as a stabilization materials of embankment slopes including agricultural reservoir and rural road etc. The experimental embankment slopes was constructed to investigate the strength properties of in-situ concrete pile with embankment materials and boring methods. The test variable were applied the boring method(driving and augering) and water-cement ratio. In order to analyze the physical and mechanical properties of embankment materials, permeability and water contents test were was performed. Also, the freshly and harden of in-situ concrete properties were measured by the slump and compressive strength tests. The results showed the water content and permeability of embankment materials and boring methods affected on compressive strength of in-situ concrete pile.

• Geomechanics and Engineering
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• v.19 no.6
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• pp.543-554
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• 2019

İzmir Bay reserves high amount of residual alluvial deposits generated by Meles River at its stream mouth. These carried sediments with high water content and low bearing capacity are unsuitable in terms of engineering purposes. In-situ soil stabilization with deep soil mixing method is considered to improve properties of soil in this location. This method is widely used especially over Scandinavia, Japan and North America. Basically, the method covers mixing appropriate binder into the soil to improve soil profile according to the engineering needs. For this purpose, soil samples were initially provided from the site, classification tests were performed and optimum ratios of lime and cement binders were determined. Following, specimens representing the in-situ soil conditions were prepared and cured to be able to determine their engineering properties. Unconfined compression tests and vane shear tests were applied to evaluate the stabilization performance of binders on samples with different curing periods. Scanning electron microscope was used to observe time-dependent bonding progress of binders in order to validate the results. Utilization of 4% lime and 4% cement mixture for the long-term performance and 8% lime and 8% cement mixture for short term performance were suggested for the stabilization of Meles Delta soils. Development of CSH and CAH in a gel form as well as CSH crystals were clearly observed on SEM images of treated specimens.

• Ecology and Resilient Infrastructure
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• v.7 no.2
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• pp.134-144
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• 2020

In-situ stabilization is a remediation method using amendments to reduce contaminant availability in contaminated soil. We tested the effects of two amendments (furnace slag and red mud) on the availability of toxic trace elements (TTEs) and soil enzyme activities (dehydrogenase, phosphatase, and urease). The application of amendments significantly decreased the availability of TTEs in soil (p < 0.05). The decreased availability of TTE content in soils was accompanied by increased soil enzyme activities. We found significant negative relationships between the TTE content assessed using Ca(NO₃)_2^-, TCLP, and PBET extraction methods and soil enzyme activities (p < 0.01). Soil enzyme activities responded sensitively to changes in the soil environment (pH, EC, and availability of TTEs). It could be concluded that soil enzyme activities could be used as bioindicators or ecological indicators for soil quality and health in environmental soil monitoring owing to their high sensitivity to changes in soil.

• Geomechanics and Engineering
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• v.5 no.4
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• pp.313-329
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• 2013

Vetiver grass (Vetiveria zizanioides) is being effectively used in many countries to protect embankment and slopes for their characteristics of having long and strong roots. In this paper, in-situ shear tests of the ground with the vetiver roots have been conducted to investigate the stabilization properties corresponding to the embankment slopes. Numerical analyses have also been performed with the finite element method using elastoplastic subloading $t_{ij}$ model, which can simulate typical soil behavior. It is revealed from field tests that the shear strength of vetiver rooted soil matrix is higher than that of the unreinforced soil. The reinforced soil with vetiver root also shows ductile behavior. The numerical analyses capture well the results of the in-situ shear tests. Effectiveness of vetiver root in geotechnical structures-strip foundation and embankment slope has been evaluated by finite element analyses. It is found that the reinforcement with vetiver root enhances the bearing capacities of the grounds and stabilizes the embankment slopes.

• Journal of Soil and Groundwater Environment
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• v.27 no.1
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• pp.1-16
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• 2022

In-situ activated carbon (AC) amendment is a promising remediation technique for the treatment of sediment impacted by hydrophobic organic contaminants (HOCs). Since its first proposal in the early 2000s, the remediation technique has quickly gained acceptance as a feasible alternative among the scientific and engineering communities in the United States and northern Europe. This review paper aims to provide an overview on in-situ AC amendment for the treatment of HOC-impacted sediment with a major focus on its working principles. We began with an introduction on the practical and scientific background that led to the proposal of this remediation technique. Then, we described how the remediation technique works in a mechanistic sense, along with discussion on two modes of implementation, mechanical mixing and thin-layer capping, that are distinct from each other. We also discussed key considerations involved in establishing a remedial goal and performing post-implementation monitoring when this technique is field-applied. We concluded with future works necessary to adopt and further develop this innovative sediment remediation technique to ongoing and future sediment contamination concerns in Korea.

• Proceedings of the Microbiological Society of Korea Conference
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• 2009.05a
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• pp.65-66
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• 2009

• Korean Journal of Environmental Agriculture
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• v.37 no.3
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• pp.179-188
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• 2018

BACKGROUND: Reclamation of heavy metal-contaminated agricultural fields has intensively been done to ensure the soil quality and food security. This study evaluated the efficiency and longevity of current physical and chemical approaches for heavy metal-contaminated soils. METHODS AND RESULTS: Concentrations of 0.1 N HCl-leachable trace metals of Cd, Pb, and As from the stabilizing agents-treated soils decreased by 50%, 70%, and 40%, respectively, compared to the control. Among the stabilizing agents, the $CaCO_3$ was the best for stabilization. For physical stabilization, the soil dressing reduced the concentrations of Cd, Pb, and As by 88%, 94%,and 88%, respectively, compared to the control. Moreover, the dilution of the contaminated soils decreased the metals by an average of 25.3% when compared with the control. The longevity of each stabilization method was determined by using the availability assessment of heavy metals in the soils. Results showed that the leaching methods using HCl and $NH_4NO_3$ had 120 and 32 weeks longevity, respectively. Interestingly, any stabilization efficacy was not found over the time for Cd and Pb (i.e., cation metals), whereas the stabilization efficacy of As was sharply decreased under 50% after 32 weeks. However, the change of metal concentration was not significant with the physical stabilization compared to the chemical stabilization. CONCLUSION: The stabilization methods should carefully be selected based on long-term monitoring under climate conditions.

• Journal of Soil and Groundwater Environment
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• v.12 no.3
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• pp.1-9
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• 2007

As Total Maximum Daily Load program is being implemented, needs for the management and treatment of contaminated sediment are rising to attain cleaner water resources. In this paper, impacts and management methods of contaminated sediment were reviewed. Remediation technologies for contaminated sediment including dredging, natural attenuation, in situ solidification/stabilization, in situ biological remediation, in situ chemical remediation and capping were reviewed. Integrated remediation scheme was presented as well.

• Corrosion Science and Technology
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• v.16 no.4
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• pp.194-200
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• 2017

Stress-corrosion cracking (SCC) of alloy 600 and alloy 800 in 0.5 mol/L thiosulfate solution during constant strain was investigated using electrochemical noise (EN) combined with 3-D microscope techniques. The in-situ morphology observation and EN results indicate that the SCC process could be divided into three stages: (1) passive film stabilization and growth, (2) crack initiation, (3) and crack growth. Power Spectral Density (PSD) and the probability distribution obtained from EN were used as the "fingerprint" to distinguish the different processes. During passive film stabilization and growth, the current noise signals resembled "white noise": when the crack initiated, many transient peaks could be seen in the current noise and the wavelet energy at low frequency as well as the noise resistance decreased. After crack propagation, the noise amplitudes increased, particularly the white noises at low and high frequencies ($W_L$ and $W_H$) in the PSDs. Finally, the detection of metal structure corrosion in a simulated sea splash zone and pipeline corrosion in the atmosphere are established.