• Applied Chemistry for Engineering
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• v.10 no.5
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• pp.726-730
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• 1999

To investigate the deinkability according to the ink composition, deinking chemicals and aging time, newspaper was printed with different solvent types: 30% soy-based oil ink(A), 50% soy-based oil ink(B), 45% mineral oil ink(C) and 42% linseed oil ink(D). The newspapers were aged naturally for 15, 30, 90, 180 days, and were deinked with various deinking chemicals. The brightness of the deinked pulp of newspaper was affected by the ink composition, aging time and deinking chemicals, i.e., it was decreased with increasing aging time in the order of C, A, B and D. And the brightness also decreased in the order of lipase, cellulase and conventional chemical. The deinking yield showed the same tendency as the brightness variation at a given brightness. The strength of the deinked pulps increased until 30 days, but decreased or maintained after that time. And the strength decreased in the order of C, D, B and A, and also decreased in the order of lipase, conventional chemicals and cellulase.

• NICE (News & Information for Chemical Engineers)
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• v.36 no.5
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• pp.544-549
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• 2018

• Journal of the Korean Society for Aeronautical & Space Sciences
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• v.46 no.6
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• pp.519-526
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• 2018

In order to analyze space resources, it had to be brought to earth. However, using laser-induced breakdown spectroscopy(LIBS) and Raman spectroscopy, it is possible to analyze qualitative and quantitative analysis of space minerals in real time. LIBS is a spectroscopic method in which a high energy laser is concentrated on a material surface to generate a plasma, and the emitted light is acquired through a spectroscope to analyze the atomic composition. Raman spectroscopy is a spectroscopic method that analyzes the molecular structure by measuring scattered light. These two spectroscopic methods are complementary spectroscopic methods for analyzing the atoms and molecules of unknown minerals and have an advantage as space payloads. In this study, data were analyzed qualitatively by using principal component analysis(PCA). In addition, a mixture of two minerals was prepared and a quantitative analysis was performed to predict the concentration of the material.

• NICE (News & Information for Chemical Engineers)
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• v.36 no.5
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• pp.542-544
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• 2018

• Journal of the Mineralogical Society of Korea
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• v.32 no.1
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• pp.63-69
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• 2019

The oxidation states of structural Fe in minerals reflect the paleo-depositional redox conditions for the biologically or abiotically induced mineral formation. Particularly, nano-scale analysis using high-resolution transmission electron microscopy (HRTEM) and electron energy loss spectroscopy (EELS) is necessary to identify evidence for the microbial role in the biomineralization. HRTEM-EELS analysis of oxidation states of structural Fe and carbon bonding structure differentiate biological factors in mineralization by mapping the distribution of Fe(II)/Fe(III) and source of organic C. HRTEM-EELS technique provides geomicrobiologists with the direct nano-scale evidence of microbe-mineral interaction.

• The Science & Technology
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• v.5 no.1 s.33
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• pp.22-22
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• 1972

• The Science & Technology
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• v.10 no.9 s.100
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• pp.95-97
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• 1977

• Economic and Environmental Geology
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• v.56 no.2
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• pp.155-166
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• 2023

Through COVID-19, the importance of supply chain management of raw material minerals has been maximized. In particular, supply chain management is important for rare metals, which are difficult to manage demand and supply, in order to secure raw materials for the parts and materials industry that Korea is actively promoting. In this study, a system was established and evaluated to select Critical minerals that need to respond to Korea's industrial structure and global risks by quantifying tangible and intangible risk factors. Global Supply Concentration, Supplying country risk, Policy Social Environment Regulation, Domestic Import Instability, Risk responsiveness, Market Scale, Demand Fluctuation and Economic Importance were evaluated as evaluation indicators. The degree of risk and risk impact were quantitatively measured using the criticality matrix-criticality level. After evaluating 40 types of minerals used in domestic new growth businesses, 15 types of Critical minerals(Li, Pt, Co, V, REE, Mg, Mo, Cr, Ti, W, C, Ni, Al, Mn, Si) in Korea were selected. The results are expected to be used to establish policies to strengthen resource security and to make decisions to form a company's raw material portfolio.

• Textile Coloration and Finishing
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• v.2 no.2
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• pp.43-50
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• 1990

색을 가지는 물질 즉 "색소" 란 인간의 눈에 시각으로서의 색을 인식 시키는 물질이다. 따라서 색소는 대상을 colorful하게 만들며 생활을 풍요롭게 하는데 필수불가결한 물질이다. 합성염료가 개발되기 이전부터 인간은 동물, 식물, 광물에서 색소를 추출해 사용해 왔다. 그러나 색소의 "색" 이외의 물성을 적극적으로 이용 할려고는 하지 않았다. 색소가 가지는 특성과 기능은 광흡수(색, 근적외 흡수, 다색성), 광방사(형광, 인광), 광 전도성, 가역변화(열, 광, pH), 화학 반응성 등이며, 이들의 특성과 기능이 색소를 광과 전자 분야에 관련되는 재료로 응용되게 유도 하였다.련되는 재료로 응용되게 유도 하였다.

• Journal of the Mineralogical Society of Korea
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• v.19 no.4 s.50
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• pp.291-300
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• 2006

This study has been carried out to reveal the mineralogical compositions, the concentrations of heavy metals, and related factors in the sediments of the Kumho River which is the main tributary of the Nakdong River. Even though this river flows in a short distance, it runs through different geology and industrial areas and can be a good candidate to study different geological and anthropogenic factors affecting the concentrations of heavy metals in the sediment. The major rock-forming minerals were quartz and albite. Minor amount of orthoclase, microcline, and amphybole were also identified. Clay minerals including illite, chlorite, kaolinite were associated with those minerals. In the downstream, no noticeable changes in species and amount of minerals were observed, indicating there is almost no influence on the mineralogical compositions from rock types. The concentrations of heavy metals in the sediments are in the order of Zn > Pb > Cu > Ni > Cr > Co > Cd. Following the downstream, the concentrations of heavy metals generally increase, except Pb. The regional increase of the heavy metal content is well correlated with the location of the tributary. Without changes in mineral compositions, the main factors controlling the heavy metal contents are the locations of pollutant sources. Except Pb and Ni, most of the concentrations of heavy metals were thought to be enriched by the past pollutant sources.