• Proceedings of the Korea Concrete Institute Conference
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• 2000.10a
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• pp.191-196
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• 2000

This study was focused on the investigation of permeability of latex modified concrete as the latex content variated such as 5%, 10%, 15%, and 20%. The rapid chloride permeability test was used to evaluate the relative permeability of latex-modified concretes and conventional concretes. The results showed that the permeability of latex-modified concretes was considerably lower than conventional concretes tested, which may be due to the latex filled in voids and interconnections of hydrated cement and aggregates by a film of latex particles.

• The Korean Journal of Ceramics
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• v.5 no.1
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• pp.35-39
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• 1999

For many years, alkali activated blast furnace slag cement containing no ordinary portland cement has received much attention in the view of energy saving and its many excellent properties. We examined the structural change of slag glass which was activated by alkali metal compounds using IR spectroscopy. The properties of hydrated products and unhydrated slag grains was characterized by XRD and micro-conduction calorimeter. Ion concentration change in the liquid during the hydration of blast furnace slag was also studied to investigated the hydration mechanism.

• Journal of the Korean Ceramic Society
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• v.21 no.3
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• pp.217-220
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• 1984

The leaching of Na-fluor-tetrasilicic mica $NaMg_{2.5}(Si_4O_{10})F_2$ (Na-TSM) in the deionized water was investigated by measuring the pH released Na and Mg contents in the suspension. According to the results it was found that $Na^+$ ions of interlayer in the Na-TSM were easily replaced by $H^+$ ions from the deionized water because $Na^+$ ions of I were repidly diffused to form a large hydrated electric double layer in the suspension.

• Journal of the Korean Ceramic Society
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• v.27 no.2
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• pp.195-200
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• 1990

For the development of low energy cement, the belite cement clinker of calcium sulphoaluminate ferrite type was synthesized at 130$0^{\circ}C$ and containing C2S, C4A3S as the major minerals along with C3A, C4AF, CS by using limestone, dolomite, clay, iron ore, gypsum and alumina as raw materials. At over 130$0^{\circ}C$, C4A3S was decomposed and thus C3A was increased. When hydrated, this cement was hardened, producing ettringite, CSH, etc.

• 한국초전도학회:학술대회논문집
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• v.11
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• pp.67-67
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• 2001

• Journal of the Mineralogical Society of Korea
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• v.2 no.1
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• pp.18-25
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• 1989

The X-ray diffraction and electron microscopy study of the kaolin sample from Sancheong area show that the halloysite occurs as hydrated 10$\AA$ form. It implies that the 7$\AA$ reflection and hk-line splitting in the X-ray diffractogram are ascribed to kaolinite. Kaolinite in Sancheong kaolin is of a disordered type. It tends to be enriched in the colored part of kaolin samples. Quantitative analyses show that kaolin contains 16-57% halloysite and 10-55%kaolinite.

• Journal of the Korean Chemical Society
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• v.14 no.3
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• pp.257-261
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• 1970

Some factors such as the weight ratio, reaction time and temperature for the separation of rare earth elements from monazite are studied. The influence of the inorganic phosphate for the leaching is also studied.

• YAKHAK HOEJI
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• v.18 no.1
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• pp.20-28
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• 1974

Physical studies of ageing inhibition of aluminum hydroxide gel were carried out. Sorbitol, mannitol and fructose were found to be an ageing inhibitor of the aluminum hydroxide gel. IR spectra and DTA curves showed that the ageing products of the gel by sorbitol orl mannitol were monohydrous alumina. This differs from hydrated hydrous alumina of other ageing products. This evidence indicates that sorbitol and mannitol prevent the hydrous alumina from its hydration.

• Bulletin of the Korean Chemical Society
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• v.19 no.4
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• pp.471-475
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• 1998

Phase shift spectroscopy is applied to Eu(Ⅲ) luminescence from $Eu^{3+}$-exchanged Y zeolite. The phase shift and intensity modulation of luminescence following intensity-modulated excitation are measured as a function of modulation frequency and they are fitted into a double exponential decay. The fast decay component, compared with the slow one, has narrower spectral bandwidth and is emitted from the $Eu^{3+}$ that has more polar and definite environment with higher symmetry and that interacts more easily with hydrated water molecules. The fast decay component is attributed to $Eu^{3+}$ at site Ⅱ' while the slow one to $Eu^{3+}$ at sites Ⅰ' and Ⅰ.

• Analytical Science and Technology
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• v.26 no.6
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• pp.395-400
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• 2013

The hydration and antimicrobial peptide effects on the lipid alignment on the surface of a thin glass plate were investigated by using the solid-state nuclear magnetic resonance spectroscopy. Pure 1-palmitoyl-2-oleoyl-sn-glycero-3-phosphotidylcholine (POPC) lipid molecules were well aligned on the surface of a thin glass plate without direct hydration by placing the sample for a few days in the desiccator containing a saturated sodium phosphate dibasic solution, which provided 95% relative humidity. But there was a big difference between two lipid phases, the one of which was hydrated by placing the sample for a few days in the desiccator with 95% relative humidity without direct hydration and the other was directly hydrated by dropping water and then placed for a few days in the same desiccator. The surface mobility of POPC molecules in a lipid bilayer phase was much activated by water. While the time for the POPC to align on the glass plate surface was short, the time for the PG-1/POPC mixture to reach the its equilibrium state was long.