There is, I think, something ethereal about i —the square root of minus one. I remember first hearing about it at school. It seemed an odd beast at that time—an intruder hovering on the edge of reality.

Usually familiarity dulls this sense of the bizarre, but in the case of i it was the reverse: over the years the sense of its surreal nature intensified. It seemed that it was impossible to write mathematics that described the real world in …

I and i

다중혈관 관상동맥 환자에서 y-문합을 이용하여 양쪽 내흉동맥만을 사용한 우회술의 조기 성적

Crystalline metal-organic frameworks (MOFs) are formed by reticular synthesis, which creates strong bonds between inorganic and organic units. Careful selection of MOF constituents can yield crystals of ultrahigh porosity and high thermal and chemical stability. These characteristics allow the interior of MOFs to be chemically altered for use in gas separation, gas storage, and catalysis, among other applications. The precision commonly exercised in their chemical modification and the ability to expand their metrics without changing the underlying topology have not been achieved with other solids. MOFs whose chemical composition and shape of building units can be multiply varied within a particular structure already exist and may lead to materials that offer a synergistic combination of properties.

The Chemistry and Applications of Metal-Organic Frameworks

J. Appl. Cryst.の発刊に際して

The long-standing challenge of designing and constructing new crystalline solid-state materials from molecular building blocks is just beginning to be addressed with success. A conceptual approach that requires the use of secondary building units to direct the assembly of ordered frameworks epitomizes this process: we call this approach reticular synthesis. This chemistry has yielded materials designed to have predetermined structures, compositions and properties. In particular, highly porous frameworks held together by strong metal-oxygen-carbon bonds and with exceptionally large surface area and capacity for gas storage have been prepared and their pore metrics systematically varied and functionalized.

/pdf/reticular-synthesis-and-the-design-of-new-materials-lazbx7tdux.pdf

Reticular synthesis and the design of new materials

Porous coordination polymer compounds consisting of Zn2+, 1,2-di(4-pyridyl)ethane, and dicarboxylates were synthesised and their crystal structures were determined. These are doubly interpenetrated 2D layer structures, and the flexibility of porous structures is dependent on the substituent group of the dicarboxylate. From gas adsorption studies, distinct adsorption isotherms were observed for CO2, CH4, C2H4, and C2H6 at 195 K and 273 K, respectively.

/pdf/soft-2d-layer-porous-coordination-polymers-with-1-2-di-4-52zgceldid.pdf

Soft 2D Layer Porous Coordination Polymers with 1,2-Di(4-pyridyl)ethane

Spherical protein cages such as an iron storage protein, ferritin, have great potential as nanometer-scale capsules to assemble and store metal ions and complexes. We report herein the synthesis of a composite of an apo-ferritin cage and Ru(p-cymene) complexes. Ru complexes were efficiently incorporated into the ferritin cavity without degradation of its cage structure. X-Ray crystallography revealed that the Ru complexes were immobilized on the interior surface of the cage mainly by the coordination of histidine residues.

Incorporation of organometallic Ru complexes into apo-ferritin cage.

Surface Pore Engineering of Porous Coordination Polymers

PROBLEM TO BE SOLVED: To obtain a polybenzazole-based polymer in which a structure for giving excellent storage stability to polybenzazole is contained in a molecular skeleton of the polymer, and to provide a polybenzazole-based fiber having excellent strength and heat resistance inherent in a fiber of the polybenzazole, decreased in deterioration of the strength even in a high-temperature high-humidity condition, and more improved in a durability performance than ever. SOLUTION: This copolymerized polybenzazole fiber is produced from the copolymerized polybenzazole having benzazole repeating units and other repeating units, wherein the copolymerized polybenzazole contains the benzazole repeating units (A), aromatic ring repeating units (B), and heterocyclic ring repeating units (C) in its molecular chain in such a proportion (a molar ratio) as to satisfy: (A)/(B)/(C)=100/(1-99)/(99-1). COPYRIGHT: (C)2005,JPO&NCIPI

Polybenzazole-based polymer and fiber given by using the same

PROBLEM TO BE SOLVED: To provide a porous material and a porosity composite material excellent in a hydrogen sulfide removing capability in a gas phase.SOLUTION: The porous composite material with a porous material in which a metal in a coordinative unsaturation state exists and carrying a silver catalyst exerts an extremely excellent hydrogen sulfide removal performance.

Susumu Kitagawa

Papers

Soft 2D Layer Porous Coordination Polymers with 1,2-Di(4-pyridyl)ethane

Incorporation of organometallic Ru complexes into apo-ferritin cage.

Surface Pore Engineering of Porous Coordination Polymers

Polybenzazole-based polymer and fiber given by using the same

Porous composite material and production method thereof, and hydrogen sulfide removing material