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Engineering topics

Seo, Dong-Kyun

Publications and source records attributed to Seo, Dong-Kyun.

Cooperative formation of porous silica and peptides on the prebiotic Earth

Significance Although catalysis by mineral surfaces has been considered to be important in prebiotic chemistry, the role of porous silica phases, with reactions taking place within specific confined environments, has not been explored. This paper proposes that structure direction through interaction of dissolved silica with organic species in aqueous solution produces porous silica catalysts for prebiotic organic reactions to form larger polymerized molecules, with possible control of chirality. This process may involve feedback and amplification if the organics produced by catalysis can also act as structure-directing agents for enhanced synthesis of the catalytic silica structures. To our knowledge, such structure direction and catalysis, though well known in materials science, have not been considered previously in the context of prebiotic chemistry.

58 GEOSCIENCES↗

Metal oxides from acidic solutions

Forming a metal oxide by treating an acidic solution containing a metal to yield a precursor in the form of a semi-liquid, semi-solid or solid, and treating the precursor to yield a product including the metal oxide. An organic or inorganic component may be combined with the precursor to yield a second semi-liquid, semi-solid or solid. The product may be treated to yield a new material. In some cases, the metal oxide has an empirical formula H.sub.xM.sub.2A.sup.1.sub.y-A.sup.2.sub.z, where M represents a transition metal or any combination of transition metals in Groups 3-12; A.sup.1 is a first oxyanion; A.sup.2 is a second oxyanion; 0.ltoreq.x.ltoreq.3; 0.ltoreq.y.ltoreq.3; 0.ltoreq.z.ltoreq.3; and y+z>0.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Geopolymer resin materials, geopolymer materials, and materials produced thereby

A product formed from a first material including a geopolymer resin material, a geopolymer material, or a combination thereof by contacting the first material with a fluid and removing at least some of the fluid to yield a product. The first material may be formed by heating and/or aging an initial geopolymer resin material to yield the first material before contacting the first material with the fluid. In some cases, contacting the first material with the fluid breaks up or disintegrates the first material (e.g., in response to contact with the fluid and in the absence of external mechanical stress), thereby forming particles having an external dimension in a range between 1 nm and 2 cm.

36 MATERIALS SCIENCE↗

Multifunctional materials and composites

Forming multifunctional materials and composites thereof includes contacting a first material having a plurality of oxygen-containing functional groups with a chalcogenide compound, and initiating a chemical reaction between the first material and the chalcogenide compound, thereby replacing oxygen in some of the oxygen-containing functional groups with chalcogen from the chalcogen-containing compound to yield a second material having chalcogen-containing functional groups and oxygen-containing functional groups. The first material is a carbonaceous material or a macromolecular material. A product including the second material is collected and may be processed further to yield a modified product or a composite.

36 MATERIALS SCIENCE↗