• Proceedings of the Polymer Society of Korea Conference
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• 2006.10a
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• pp.29-30
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• 2006

The synthesis of dendritic dipeptides $(4-3,4-3,5)12G2-CH_{2}-Boc-_{L}-Tyr-X-OMe\;where\;X\;=\;Gly,\;_{L}-Val,\;_{L}-Leu,\;_{L}-Ile,\;_{L}-Phe$, and L-Pro will be discussed. Their self-assembly in bulk and in solution and the structural and retrostructural analysis of their periodic assemblies will be compared to that of the previously reported and currently reinvestigated dendritic dipeptide with $X=_{L}-Ala$. All dendritic dipeptides containing as X nonpolar ${\alpha}-amino$ acids self-assemble into helical porous columns. The principles via which the aliphatic and aromatic substituents of X program the structure of the helical pores indicate synthetic pathways to helical pores with bioinspired functions based on artificial nonpolar ${\alpha}-amino$ acids will be discussed.

• Animal Systematics, Evolution and Diversity
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• v.24 no.2
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• pp.161-164
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• 2008

As a result of a taxonomic study on the earthworm material collected from Namat National Biodiversity Conservation Area (NBCA), Hoaphane Province, Laos, a new species, Pithemera viengthongensis sp. novo is described from near Namchong river, Viengthong district. The new species bearing two pairs of spermathecal pores in 7/8, 8/9 is not assignable to any other species of Pithemera as defined by Sims and Easton (1972). In the new species, the male pore region has kidney-shaped pads extending between XVII-19/20, the male pores and spermathecal pores are 0.31 circumference apart, and genital papillae are lacking. The ventral view of anterior body region and the spermathecae are illustrated.

• ALGAE
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• v.29 no.3
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• pp.197-201
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• 2014

This is the first recorded observation of Akashiwo sanguinea excreting mucilaginous substances from pores on the cell surface. Observations were from samples collected in the Caloosahatchee Estuary, Florida, USA during a bloom event, with densities of 672 cells $mL^{-1}$ of A. sanguinea, including 51 cells surrounded by mucous. Scanning electron microscopy observations revealed that the mucous was secreted from thecal pores on the cell surface. The potential significance of mucous production is discussed.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.606-607
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• 2006

A porous material with a surface layer was fabricated using glass abrasive sludge and expanding agents. The glass abrasive sludges were mixed with expanding agents and compacted into pellets. These pellets were sintered in the range of $700-900^{\circ}C$ for 20min. The sintered porous materials had a surface layer with smaller pores and inner parts with larger pores. The surface layer and pores controlled the absorption ratio and physical properties.

• Animal Systematics, Evolution and Diversity
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• v.30 no.2
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• pp.81-86
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• 2014

Three new species of Amynthas (Clitellata: Megascolecidae) were discovered in the Nam Ha National Protected Area (NPA) of Laos. These are Amynthas namhaensis sp. nov., Amynthas vanhi sp. nov., and Amynthas angtanensis sp. nov. Amynthas namhaensis sp. nov. and Amynthas vanhi sp. nov. are athecal, with male pores 0.14-0.17 and 0.17-0.19 circumference apart ventrally, respectively. Amynthas angtanensis sp. nov. has four pairs of spermathecal pores on 4/5-7/8, with male pores very closely set at 0.07-0.1 circumference apart. Descriptions of the new species are provided, including illustrations of the ventral view, intestinal caeca, and spermathecae.

• Proceedings of the Korean Powder Metallurgy Institute Conference
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• 2006.09a
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• pp.557-558
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• 2006

In all conventional sintered PM products, the pores present are of two types, primary and secondary. Primary pores forming during compaction and latter during sintering, due to penetration of formed liquid through the matrix grain boundary. Effect of carbon addition on diffusion of Cu in SH737-2Cu system was investigated. After compaction and transient liquid phase sintering at $1120^{\circ}C$ and $1180^{\circ}C$, samples were characterized for densification, showing rise in sintering density and reduction in swelling on carbon addition. Quantitative microstructural characterization (shape factor and pore size) revealed bimodal distribution for 0% carbon, more rounded pores for 0.9% carbon and higher sintering temperature, and pore coarsening at higher sintering temperature.

• Proceedings of the Membrane Society of Korea Conference
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• 1996.10a
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• pp.3-7
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• 1996

A rigorous analysis on the effect of colloidal interactions on the separation characteristic has been extended to the case of non-dilute charged solute concentration. The solute partitioning within slit pores for a wide range of solute concentration has been predicted by performing the Monte Carlo technique. Using a hindered transport model, rejection coefficients have been estimated from the predicted concentration profile.

• Journal of Electrical Engineering and Technology
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• v.6 no.5
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• pp.688-692
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• 2011

Carbon nanotubes (CNTs) are vertically grown inside high-aspect-ratio vertical pores of anodized aluminum oxide. A CNT catalyst layer is introduced by atomic layer deposition to the bottom of the pores, after which the CNTs are successfully grown from the layer using chemical vapor deposition. The CNTs formed a complete vertical conductive path. The conductivity of the CNT-vertical path is also measured and discussed. The present atomic layer deposition-incorporated catalyst deposition is predicted to enable the integration of CNTs with various challenging configurations, including high-aspect-ratio vertical channels or vertical interconnects.

• Journal of the Korean institute of surface engineering
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• v.33 no.4
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• pp.261-265
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• 2000

Geometrically and chemically well defined Pt/alumina model catalysts have been prepared. To this end, we fabricated electrochemically alumina supports in which pores of constant size, length and shape were regularly distributed over a wide area of the surface. Platinum particles were dispersed on the pore surfaces via organometallic chemical vapor deposition technique using (trimethyl) methylcyclopentadienylplatinum (IV) as a precursor. The chemical composition of the alumina plane surfaces was examined by Auger electron spectroscopy and the adsorption characteristics of the platinum particles were studied by thermal desorption spectroscopy. A variety of industrial catalytic problems are now open for further investigation utilizing the Pt/alumina model catalysts.

• Journal of the Korean Vacuum Society
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• v.6 no.S1
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• pp.66-69
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• 1997

Porosity is one important characteristic feature and structural index of sprayed coatings. A method of measurement of porosity, EPMA-EDS image processing is developed in the paper. The characteristics of pores can be determined by processing of the image obtained from an electron microscope via VISTA, Not only the porosity can be presented but also the statistical result of pore size distribution. Finally it can be drawn from this paper that EPMA-EDS is a quite effective method to completely characterize the pores in plasma sprayed coatings.