• Journal of Korean Society of Environmental Engineers
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• v.37 no.6
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• pp.325-331
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• 2015

The experimental results of the characteristics of aluminum based and ferric based coagulants for the Nakdong River water showed that the main hydrolysis species contained in alum and $FeCl_3$ are monomeric species of 98% and 93.3%, respectively. The PACl of r=1.2 produced by the addition of base contained 31.2% of polymeric Al species and the PACl of r=2.2 contained 85.0% of polymeric Al species, as showing more polymeric Al species with increasing r value. Coagulation tests using Al(III) and Fe(III) salts coagulants for the Nakdong River water showed that the coagulation effectiveness of turbidity and organic matter was high in the order of $FeCl_3$ > PACl (r=2.2) > PACl (r=1.2) > alum. $FeCl_3$ has showed better flocculation efficiency than Al(III) salts coagulants. In addition, in case of Al(III) coagulants, the Al(III) coagulants of higher basicity, which contained more polymeric Al species, resulted in better coagulation efficiency for both turbidity and organic matter removed. The optimum pH range for all of the coagulants investigated was around pH 7.0 under the experimental pH range of 4.0~9.5. Especially, the highest basicity PACl (r=2.2) and $FeCl_3$ were considered as more appropriate coagulants for the removal of turbidity in the case of raw water exhibiting higher pH.

• Korean Journal of Plant Taxonomy
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• v.36 no.4
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• pp.263-277
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• 2006

Anemone pendulisepala, recently described as a new species, is distributed in sympatry with A. reflexa, A. amurensis, and A. raddeana at Mt. taebeark and Mt. Baekdu. Anemone pendulisepala was previously proposed to be a hybrid species between A. reflexa and A. amurensis becaue it displavs overlapping features with them in involucre shape, petiole length, sepal apex and xylem shape, To verify the taxonomic status and to examine the hybridity of A. pendulisepala, sequences of ITS region of nuclear ribosomal DNA and the psba-trnH, rps16 and trnLF region of cpDNA from 36 accessions of 5 taxa including outgroup were analyzed. In maximum parsimony tree based on ITS sequences, A. pendulisepala had the same sequences of A. reflexa and was clustered with monophyletic A. amurensis, and then A. raddeana. Anemone pendulisepala was distinguished from the other taxa by having four base insertion in rps16 region, two species-specific bases and insertion in trnLF region. In the phylogenetic trees of combined cpDNA, A. pendulisepala showed monophyly with the bootstrap 100%. Anemone pendulisepala exhibited no polymorphism and shared no sequences with putative parental or related taxa examined in this study. Molecular data suggest that A. pendulisepala should be a distinct species, and no evidence of the hybridization was detectcd.

• Resources Recycling
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• v.20 no.3
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• pp.55-61
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• 2011

In order to develop economical production process from metallurgical grade silicon(MG-Si) to solar grade(SOG-Si), removal of boron by slag treatment was investigated at 1823 K using CaO-$SiO_2$ based slags. In the present study boron removal ratio in CaO-$SiO_2$ stags and $CaCO_3-SiO_2$ slags were increased to 63% and 73% respectively with slag basicity (%CaO/$%SiO_2$). However, bubbling time with Ar gas of slag and metal was not affected on removal ratio of boron. The addition of $Na_2CO_3$ to CaO-$SiO_2$ slags did not improve the removal ratio of boron from molten silicon. Boron contend was decreased from 20.6 ppm to 1.03 ppm by three times treatment using $CaCO_3-SiO_2$ slag (basicity=1.2).

• The KIPS Transactions:PartB
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• v.18B no.2
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• pp.67-72
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• 2011

Single nucleotide polymorphisms (SNPs) are a very important tool for the study of human genome structure. Cluster analysis of the large amount of gene expression data is useful for identifying biologically relevant groups of genes and for generating networks of gene-gene interactions. In this paper we compared the clusters of SNPs within asthma group and normal control group obtained by using hierarchical cluster analysis method with entropy distance. It appears that the 5-cluster collections of the two groups are significantly different. We searched the best set of SNPs that are useful for diagnosing the two types of asthma using representative SNPs of the clusters of the asthma group. Here support vector machines are used to evaluate the prediction accuracy of the selected combinations. The best combination model turns out to be the five-locus SNPs including one on the gene ALOX12 and their accuracy in predicting aspirin tolerant asthma disease risk among asthmatic patients is 66.41%.

• Applied Chemistry for Engineering
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• v.16 no.4
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• pp.588-593
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• 2005

In this study, biodegradable poly(${\varepsilon}$-caprolactone) (PCL) microcapsules containing chemically treated $SiO_2$ and nifedipine were prepared by oil-in-water (O/W) emulsion solvent evaporation method. The microcapsules containing drugs were confirmed using FT-IR spectra. The morphologies of the microcapsules were observed with scanning electron microscope (SEM). The nifedipine's release behaviors from the microcapsules were also examined with UV/vis spectroscopy. As a result, the inclusion of nifedipine into the microcapsules was determined by the presence of nifedipine's specific peak, i.e., C=O stretch vibration at $1682cm^{-1}$. The average particle size of the microcapsules decreased with increasing stirring rate. The nifedipine adsorption capacity and release rate of treated $SiO_2$ that was treated with basic solution decreased because with the increased basicity it lowered the specific surface area of $SiO_2$ and promoted stronger acid-base interactions between $SiO_2$ and nifedipine.

• Proceedings of the Korean Institute of Resources Recycling Conference
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• 2002.05a
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• pp.105-106
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• 2002

• Proceedings of the Korean Radioactive Waste Society Conference
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• 2006.06a
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• pp.95-96
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• 2006

• Proceedings of the Korean Ceranic Society Conference
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• 2002.10a
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• pp.144.1-144
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• 2002

• Elastomers and Composites
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• v.34 no.3
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• pp.222-228
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• 1999

In this work, the effect of chemical treatments on the carbon blacks as-received has been studied in the context of surface, adsorption, microstructure properties, and physical surface free energetics. As an experimental result, the basic chemical treatment leads to an increase in the either dispersive or specific component without significant change the pH and specific surface area. While, acidic chemical treatment do significantly change the surface and adsorption properties, and microstructures of the carbon blacks. In particular, the result given by basic chemical treatment shows an increase of the London dispersive component of the surface free energy which is a major parameter in evaluating the dispersion or specific surface area of the carbon blacks studied. This is probably a major role in evaluating the dispersion the carbon blacks, which are reinforced in elastomer matrix in a composite system.

• Polymer(Korea)
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• v.25 no.4
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• pp.587-593
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• 2001

In this work, red mud (RM) was chemically modified by 0.1, 1, and 5 M H3PO4 solution to prepare epoxy/RM nanocomposites. The effect of chemical treatment on pH, acid-base values, specific surface area, and porosity of RM surface was analyzed. To estimate the mechanical interfacial properties of epoxy/RM nanocomposites, the critical stress intensity factor (K$_{IC}$) was measured. From the experimental results, it was clearly revealed that the porosity, specific surface area, and acid values of RM surface were developed as the increase of the treatment concentration due to the increase of acidic functional group, including hydroxyl group on RM surface. The mechanical interfacial properties of epoxy/treated-RM nanocomposites were higher than those of epoxy/RM as-received due to an improvement of interfacial bonding between basic matrix and RM surface.