• Proceedings of the Korean Environmental Health Society Conference
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• 2005.06a
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• pp.378-380
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• 2005

The waste seashells were used for the removal of hydrogen sulfide from a hot gas stream, The sulphidation of waste seashells with H$_2$S was studied in a thermogravimetric analyzer at temperature between 600 and 800${\circ}$C . The desulfurization performance of the waste seashell sorbents was experimentally tested in a fixed bed reactor system. Sulfidation experiments performed under reaction conditions similar to those at the exit of a coal gasifier showed that preparation procedure and technique, the type and the amount of seashell, and the size of the seashell affect the H2S removal capacity of the sorbents. The pore structure of fresh and sulfided seashell sorbents was analyzed using mercury porosimetry, nitrogen adsorption, and scanning electron microscopy.

• Proceedings of the Korea Concrete Institute Conference
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• 1999.04a
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• pp.443-448
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• 1999

Tests have been carried out on four concrete containing different levels of silica fume to measure their permeability coefficient using water and oxygen, chloride ion. The total cementitious content was 351kg/㎥, and the water/cementitious materials ratio was 0.55. The results show that a dramatic reduction in permeability of concrete containing silica fume occurs due to formation of a discontinuous macro-pore system which inhibits flow. Porosity estimates from mercury-intrusion porosimetry are used to develop an explanations for the water and air permeability reduction. And, results of the rapid permeability test showed that the resistance of concrete to the penetration of chloride ions increases significantly as a contents of silica-fume is increased. The current intensity passing through the concrete containing silica fume is presented from 664C to 2166C.

• Proceedings of the Korea Concrete Institute Conference
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• 2009.05a
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• pp.425-426
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• 2009

As a result of the Mercury Intrusion Porosimetry(MIP) test, FCR Batch with the continuous voids in excellent permeability is appeared with the Cellular Mortar that is most suitable which Drain Material of the Composite Lining Method.

• Carbon letters
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• v.2 no.1
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• pp.55-60
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• 2001

Graphite intercalation compounds (GIC) were prepared by direct reaction of $SO_3$ gas with flake graphite. The intercalated $SO_3$ molecules were ejected by rapid heating to $950^{\circ}C$ under an oxidizing atmosphere for about 1 minute, resulting in surprisingly high expansion in the direction of c-axis. The characteristics of the micro-structure and pore size distribution were examined with a SEM and mercury intrusion porosimetry. The XRD analysis and spectroscopic analysis were used for the identification of the graphite and surface chemistry state. The pore size distribution of the exfoliated graphite (EG) was a range of $1{\sim}170{\mu}m$. The higher expanding temperature the higher expanded volume, so oil sorption capacities were 58.8 g of bunker-C oil and 34.7 g of diesel oil per 1 g of the the EG. The sorption equilibrium was achieved very rapidly within several minutes. As the treatment temperature increases, bulk density decreases.

• Proceedings of the Korea Concrete Institute Conference
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• 2010.05a
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• pp.199-200
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• 2010

This paper was estimated the diffusion coefficient through the chlorine ion diffusion coefficient of the high fluidity concrete using the limestone powder. Also, the micro void of high fluidity concrete examined according to the mixing ratio of the limestone powder by the mercury intrusion porosimetry.

• Computers and Concrete
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• v.22 no.1
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• pp.83-91
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• 2018

Various systems for simulating particulate matter are developed and used in concrete technology for producing virtual cementitious materials on the different levels of the microstructure. Basically, the systems can be classified as two distinct families, namely random sequential addition systems (RSAs) and discrete element methods (DEMs). The first type is hardly being used for this purpose outside concrete technology, but became popular among concrete technologists. Hence, it is of utmost relevance to compare the two families in their capabilities, so that the reliability of produced data can be estimated. This paper pursues to do this on the basis of earlier published material of work performed by a succession of PhD students in the group of the second author. Limited references will be given to external sources.

• Geomechanics and Engineering
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• v.23 no.5
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• pp.431-439
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• 2020

Soil-water retention curve (SWRC) contains key information for the application of unsaturated soil mechanics principles to engineering practice. The SWRC variables are commonly used to describe the hydro-mechanics of soils. Generally, these parameters are determined using the graphical method which can be time consuming. The SWRC is highly dependent on the pore size distribution (PSD). Theoretically, the PSD obtained by mercury intrusion porosimetry test can be used to determine some SWRC variables. Moreover, the relationship between SWRC and shrinkage curve has been investigated. A new method to determine total SWRC variables directly without curve-fitting procedure is proposed. Substituting the variables into linear SWRC equations construct SWRC. A good agreement was obtained between predicted and measured SWRCs, indicating the validity of the proposed method for unimodal SWRC.

• Journal of the Korean Ceramic Society
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• v.25 no.2
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• pp.89-94
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• 1988

Alumina gel was prepared by the hydrolysis of aluminum isopropoxide Al(OC3H7i)3 at low temperature. Sample were calcined at the various temperatures for 10 houres in the electric furnace, respectively. In order to investigate the various propertis-thermal properties, pore size and distribution, and the transition of crystals, infrared spectroscopy, thermal analysis, particle size analysis, scanning electron microscopy, and porosimetry were employed. Transparent alumina gel was opalized at 1200$^{\circ}C$. Porosity was about 87% with pores below 0.7$\mu\textrm{m}$ and 55% at 1200$^{\circ}C$. The gel was transformed along the rising of temperature as follows; Boehmite\longrightarrow$\delta$-Al2O3\longrightarrow$\theta$\longrightarrowAl2O3\longrightarrow${\alpha}$-Al2O3.

• Computers and Concrete
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• v.7 no.1
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• pp.17-38
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• 2010

This research aimed to investigate the influence of high-volume mineral admixtures (MAs), i.e., fly ash and slag, on the hydration characteristics and microstructures of cement pastes. Degree of cement hydration was quantified by the loss-on-ignition technique and degree of pozzolanic reaction was determined by a selective dissolution method. The influence of MAs on the pore structure of paste was measured by mercury intrusion porosimetry. The results showed that the hydration properties of the blended pastes were a function of water to binder ratio, cement replacement level by MAs, and curing age. Pastes containing fly ash exhibited strongly reduced early strength, especially for mix with 45% fly ash. Moreover, at a similar cement replacement level, slag incorporated cement paste showed higher degrees of cement hydration and pozzolanic reaction than that of fly ash incorporated cement paste. Thus, the present study demonstrates that high substitution rates of slag for cement result in better effects on the short- and long-term hydration properties of cement pastes.

• Bulletin of the Korean Chemical Society
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• v.27 no.1
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• pp.53-58
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• 2006

A powder of destructive adsorbent was prepared by impregnating Mn and Cu on the surface of amorphous aluminosilicate. It catalytically dimerized tert-butyl mercaptan into di-tert-butyl disulfide on its surface. Turnover of the dimerization was strongly dependent on the surface morphology of the adsorbent, which could be altered by modification of aluminosilicate support. During the process of impregnation, which involved heat treatment at 500 ${^{\circ}C}$, the shape of the pore was preserved, though large fraction of micropores were eliminated. The reactive sites on the surface were poisoned as dimerization products strongly adhered on them. Therefore, high surface area was not always desirable. When the surface was heavily populated with “inkbottled” pores with a narrow entrance in uniform size, heavy poisoning of the reactive sites turned the destructive adsorbents almost useless.