• Journal of Korean Society of Environmental Engineers
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• v.28 no.12
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• pp.1337-1346
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• 2006

Soil humin is the insoluble fraction of humic materials and play an important roles in the irreversible sorption of hydrophobic organic contaminants onto soil particles. However, there have been limited knowledge about the sorption and chemical properties of humin due to the difficulties in its separation from the inorganic matrix(mainly clays and oxides). In this study, de-ashed soil humins($Hu_1-Hu_6$) were isolated from a soil residues(Crude Hu) after removing alkali-soluble organic fractions followed by consecutive dissolution of the mineral matrix with 2%-HF for 2 hr. The humin samples were characterized by elemental analysis and $^{13}C$ NMR spectroscopic method and their sorption-desorption behavior for 1-naphthol were investigated from aqueous solution. The results were compared one another and that with peat humin. $^{13}C$ NMR spectra features indicate that the soil humin molecules are mainly made up of aliphatic carbons(>80% in total carbon) including carbohydrate, methylene chain. Freundlich sorption parameter, n was increased from 0.538 to 0.697 and organic carbon-normalized sorption coefficient(log $K_{OC}$) values also increased from 2.43 to 2.74 as inorganic matrix of the soil humin removed by HF de-ashing. The results suggest that inorganic phase in humin plays an important, indirect role in 1-naphthol sorption and the effects on the sorption non-linearity and intensity are analyzed by comparison between the results of soil humin and peat humin. Sorption-desorption hysteresis were also observed in all the humin samples and hysteresis index(HI) at low solute concentration($C_e$=0.1 mg/L) are in order of Peat humin(2.67)>De-ashed humin(0.74)>Crude Hu(0.59).

• Journal of Conservation Science
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• v.34 no.6
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• pp.595-604
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• 2018

In this study, in a bid to develop natural bioadhesives for paper craft, the hanji industry, and preserving cultural assets, complex polysaccharides were extracted from brown and red algae and used as an ingredient in adhesives. Brown algae include sea trumpet, kelp, sea oak, and sea mustard, whereas red algae include Pachymeniopsis elliptica agar-agar weed, Gloiopeltis tenax, and hunori. The polysaccharides were extracted after transforming them from non-aqueous Ca complexes contained in each of the brown and red algae into water-soluble polysaccharides containing alkali metals with a solubility level of 1. and extracted Subsequently, only the polysaccharides were extracted using alcohol precipitation. The adhesion tensile strengths of kelp, a brown algae, and Pachymeniopsis elliptica, a red algae, were 21.58 and 32.99 kgf, respectively. They thus demonstrated better adhesion than that of solid glue products such as water plants (18.45 kgf) and glue sticks (20.45 kgf). The extraction yield of these polysaccharides is supposed to be determined according to their extracted environments; however, no difference in adhesion strength was seen. Further, it was found that the shapes of polysaccharides were determined by their growing environment instead of extraction environment. Use of multi-step alcohol precipitation method during extraction enabled the removal of the constituents except protein and other polysaccharides, thereby demonstrating a stable outcome without cultivation of mold. Furthermore, there was no occurrence of mold even after production of the adhesives by the simple solution method, which demonstrates the adhesive's potential as an environment-friendly adhesive material.