• Title/Summary/Keyword: in situ monitoring

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Assessment of Environmental Pollution with Tradescantia Bioassays (자주달개비 생물검정 기법을 이용한 환경오염 평가)

  • Kim Jin Gyu;Sin Hae Sik
    • Proceedings of the Korea Society of Environmental Biology Conference
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    • 2004.05a
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    • pp.1-15
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    • 2004
  • Higher plants can be valuable genetic assay systems for monitoring environmental pollutants and evaluating their biological toxicity. Two assays are considered ideal for in situ monitoring and testing of soil, airborne and aqueous mutagenic agents; the Tradescantia stamen hair assay for somatic cell mutations and the Tradescantia micronucleus assay for chromosome aberrations. Both assays can be used for in vivo and in vitro testing of mutagens. Since higher plant systems are now recognized as excellent indicators and have unique advantages over in situ monitoring and screening, higher plant systems could be accepted by regulatory authorities as an alternative first-tier assay system for the detection of possible genetic damages resulting from the pollutants or chemicals used and produced by industrial sectors. It has been concluded that potential mutagen and carcinogen such as the heavy metals among indoor air particulates, volatile compounds in the working places, soil, and water pollutants contribute to the overall health risk. This contribution can be considerable under certain circumstances. It is therefore important to identify the level of genotoxic activity in the environment and to relate it to the biomarkers of a health risk in humans. The results from the higher plant bioassays could make a significant contribution to assessing the risks of pollutants and protecting the public firom agents that can cause mutation anuor cancer. The plant bioassays, which are relatively inexpensive and easy to handle, are recommended for the scientists who are interested in monitoring pollutants and evaluating their environmental toxicity to living organisms.

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Nano-Scale Observation of Nanomaterials by In-Situ TEM and Ultrathin SiN Membrane Platform

  • An, Chi-Won
    • Proceedings of the Korean Vacuum Society Conference
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    • 2013.02a
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    • pp.657-657
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    • 2013
  • In-situ observations of nano-scale behavior of nanomaterials are very important to understand onthe nano-scale phenomena associated with phase change, atomic movement, electrical or optical properties, and even reactions which take place in gas or liquid phases. We have developed on the in-situ experimental technologies of nano-materials (nano-cluster, nanowire, carbon nanotube, and graphene, et al.) and their interactions (percolation of metal nanoclusters, inter-diffusion, metal contacts and phase changes in nanowire devices, formation of solid nano-pores, melting behavior of isolated nano-metal in a nano-cup, et al.) by nano-discovery membrane platform [1-4]. Between two microelectrodes on a silicon nitride membrane platform, electrical percolations of metal nano-clusters are observed with nano-structures of deposited clusters. Their in-situ monitoring can make percolation devices of different conductance, nanoclusters based memory devices, and surface plasmonic enhancement devices, et al. As basic evidence on the phase change memory, phase change behaviors of nanowire devices are observed at a nano-scale.

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Synthesis of Pd/Cu-Fe polymetallic nanoparticles for in situ reductive degradation of p-nitrophenol

  • Wenbin, Zhang;Lanyu, Liu;Jin, Zhao;Fei, Gao;Jian, Wang;Liping, Fang
    • Membrane and Water Treatment
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    • v.13 no.2
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    • pp.97-104
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    • 2022
  • With a small particle size, specific surface area and chemical nature, Pd/Cu-Fe nanocomposites can efficiently remove the organic compounds. In order to understand the applicability for in situ remediation of contaminated groundwater, the degradation of p-nitrophenol by Pd/Cu-Fe nanoparticles was investigated. The degradation results demonstrated that these nanoparticles could effectively degrade p-nitrophenol and near 90% of degradation efficiency was achieved by Pd/Cu-Fe nanocomposites for 120 min treatment. The efficiency of degradation increased significantly when the Pd content increased from 0.05 wt.% and 0.10 wt.% to 0.20 wt.%. Meanwhile, the removal percentage of p-nitrophenol increased from 75.4% and 81.7% to 89.2% within 120 min. Studies on the kinetics of p-nitrophenol that reacts with Pd/Cu-Fe nanocomposites implied that their behaviors followed the pseudo-first-order kinetics. Furthermore, the batch experiment data suggested that some factors, including Pd/Cu-Fe availability, temperature, pH, different ions (SO42-, PO43-, NO3-) and humic acid content in water, also have significant impacts on p-nitrophenol degradation efficiency. The recyclability of the material was evaluated. The results showed that the Pd/Cu-Fe nanoparticles have good recycle performance, and after three cycles, the removal rate of p-nitrophenol is still more than 83%.

Performance of Tall Buildings in Urban Zones: Lessons Learned from a Decade of Full-Scale Monitoring

  • Kijewski-Correa, T.;Kareem, A.;Guo, Y.L.;Bashor, R.;Weigand, T.
    • International Journal of High-Rise Buildings
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    • v.2 no.3
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    • pp.179-192
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    • 2013
  • The lack of systematic validation for the design process supporting tall buildings motivated the authors' research groups and their collaborators to found the Chicago Full-Scale Monitoring Program over a decade ago. This project has allowed the sustained in-situ observation of a collection of tall buildings now spanning worldwide. This paper overviews this program and the lessons learned in the process, ranging from appropriate technologies for response measurements to the factors influencing accurate prediction of dynamic properties all the way to how these properties then influence the prediction of response using wind tunnel testing and whether this response does indeed correlate with in-situ observations. Through this paper, these wide ranging subjects are addressed in a manner that demonstrates the importance of continued promotion and expansion of full-scale monitoring efforts and the ways in which these programs can provide true value-added to building owners and managers.

In Situ Single Cell Monitoring by Isocyanide-Functionalized Ag and Au Nanoprobe-Based Raman Spectroscopy

  • Lee, So-Yeong;Jang, Soo-Hwa;Cho, Myung-Haing;Kim, Young-Min;Cho, Keun-Chang;Ryu, Pan Dong;Gong, Myoung-Seon;Joo, Sang-Woo
    • Journal of Microbiology and Biotechnology
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    • v.19 no.9
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    • pp.904-910
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    • 2009
  • The development of effective cellular imaging requires a specific labeling method for targeting, tracking, and monitoring cellular/molecular events in the living organism. For this purpose, we studied the cellular uptake of isocyanide-functionalized silver and gold nanoparticles by surface-enhanced Raman scattering (SERS). Inside a single mammalian cell, we could monitor the intracellular behavior of such nanoparticles by measuring the SERS spectra. The NC stretching band appeared clearly at ${\sim}2,100cm^{-1}$ in the well-isolated spectral region from many organic constituents between 300 and 1,700 or 2,800 and $3,600cm^{-1}$. The SERS marker band at ${\sim}2,100cm^{-1}$ could be used to judge the location of the isocyanide-functionalized nanoparticles inside the cell without much spectral interference from other cellular constituents. Our results demonstrate that isocyanide-modified silver or gold nanoparticle-based SERS may have high potential for monitoring and imaging the biological processes at the single cell level.

The Theory and Application of Diffusive Gradient in Thin Film Probe for the Evaluation of Concentration and Bioavailability of Inorganic Contaminants in Aquatic Environments (박막분산탐침(diffusive gradient in thin film probe)의 수중 생물학적 이용가능한 중금속 측정 적용)

  • Hong, Yongseok
    • Journal of Korean Society on Water Environment
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    • v.29 no.5
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    • pp.691-702
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    • 2013
  • This review paper summarizes the theory, application, and potential drawbacks of diffusive gradient in thin film (DGT) probe which is a widely used in-situ passive sampling technique for monitoring inorganic contaminants in aquatic environments. The DGT probe employs a series of layers including a filter membrane, a diffusive hydrogel, and an ionic exchange resin gel in a plastic unit. The filter side is exposed to an aquatic environment after which dissolved inorganic contaminants, such as heavy metals and nuclides, diffuse through the hydrogel and are accumulated in the resin gel. After retrieval, the contaminants in the resin gel are extracted by strong acid or base and the concentrations are determined by analytical instruments. Then aqueous concentrations of the inorganic contaminants can be estimated from a mathematical equation. The DGT has also been used to monitor nutrients, such as ${PO_4}^{3-}$, in lakes, streams, and estuaries, which might be helpful in assessing eutrophic potential in aquatic environments. DGT is a robust in-situ passive sampling techniques for investigating bioavailability, toxicity, and speciation of inorganic contaminants in aquatic environments, and can be an effective monitoring tool for risk assessment.