Abstract: Proposed is an automatic liquid drain device including a body (10) having a water collection chamber (12) and configured such that an upper cap member (11) having a liquid inlet (13) is fastened to an upper portion of the water collection chamber (12), a buoyancy valve member (20) embedded to be vertically movable in the water collection chamber (12), having downward-inclined ribs (23) and a drop drain (24), and provided with a valve packing (25) protruding from a lower center thereof, a liquid pooling space (122) below the buoyancy valve member (20), and a drain emergency action means (30) provided with a drain nipple (31) having a vertical drain hole (32) whose upper end is exposed to the liquid pooling space (122), and an opening/closing nipple (34) fastened to a lower portion of the drain nipple (31) to open and close the vertical drain hole (32).

Abstract: Iron oxide nano contrast agents for Magnetic Resonance Imaging which have superior T2 contrast effect, and also can be used as a storage or a carrier for drugs and so on, are disclosed. The iron oxide nano contrast agents can be prepared by the steps of: coating surfaces of hydrophobic FeO nanoparticles with a coating material selected from the group consisting of polyethylene glycol-phospholipid conjugate, dextran, chitosan, dimercaptosuccinic acid and mixtures thereof in an organic solvent to form hydrophilic FeO nanoparticles having hydrophilic surfaces and dispersibility in water; dispersing the hydrophilic FeO nanoparticles in water to oxidize FeO; and exposing the oxidized hydrophilic FeO nanoparticles to an acidic buffer to dissolve and remove interior unoxidized FeO portions, and thereby to form Fe3O4 nanoparticles having an interior space.

Abstract: Iron oxide nano contrast agents for Magnetic Resonance Imaging which have superior T2 contrast effect, and also can be used as a storage or a carrier for drugs and so on, are disclosed. The iron oxide nano contrast agents can be prepared by the steps of: coating surfaces of hydrophobic FeO nanoparticles with a coating material selected from the group consisting of polyethylene glycol-phospholipid conjugate, dextran, chitosan, dimercaptosuccinic acid and mixtures thereof in an organic solvent to form hydrophilic FeO nanoparticles having hydrophilic surfaces and dispersibility in water; dispersing the hydrophilic FeO nanoparticles in water to oxidize FeO; and exposing the oxidized hydrophilic FeO nanoparticles to an acidic buffer to dissolve and remove interior unoxidized FeO portions, and thereby to form Fe3O4 nanoparticles having an interior space.

Abstract: Iron oxide nano contrast agents for Magnetic Resonance Imaging which have superior T2 contrast effect, and also can be used as a storage or a carrier for drugs and so on, are disclosed. The iron oxide nano contrast agents can be prepared by the steps of: coating surfaces of hydrophobic FeO nanoparticles with a coating material selected from the group consisting of polyethylene glycol-phospholipid conjugate, dextran, chitosan, dimercaptosuccinic acid and mixtures thereof in an organic solvent to form hydrophilic FeO nanoparticles having hydrophilic surfaces and dispersibility in water; dispersing the hydrophilic FeO nanoparticles in water to oxidize FeO; and exposing the oxidized hydrophilic FeO nanoparticles to an acidic buffer to dissolve and remove interior unoxidized FeO portions, and thereby to form Fe3O4 nanoparticles having an interior space.

Abstract: Iron oxide nano contrast agents for Magnetic Resonance Imaging which have superior T2 contrast effect, and also can be used as a storage or a carrier for drugs and so on, are disclosed. The iron oxide nano contrast agents can be prepared by the steps of: coating surfaces of hydrophobic FeO nanoparticles with a coating material selected from the group consisting of polyethylene glycol-phospholipid conjugate, dextran, chitosan, dimercaptosuccinic acid and mixtures thereof in an organic solvent to form hydrophilic FeO nanoparticles having hydrophilic surfaces and dispersibility in water; dispersing the hydrophilic FeO nanoparticles in water to oxidize FeO; and exposing the oxidized hydrophilic FeO nanoparticles to an acidic buffer to dissolve and remove interior unoxidized FeO portions, and thereby to form Fe3O4 nanoparticles having an interior space.

Abstract: A process for preparation of RNA using an affinity column and a DNAzyme is disclosed. By the process, a target RNA can be mass-produced with a high yield, a high resolution and a high purification efficiency. The process includes the steps of preparing a RNA adduct including a target RNA and a tail RNA sequence which is affixed to the 3′-terminal of the target RNA and can complementary combine with an oligo-dN sequence of an oligo-dN affinity column; purifying the RNA adduct by combining the RNA adduct to the oligo-dN affinity column; and obtaining the target RNA by cleaving the purified RNA adduct with a DNAzyme. Preferably, the process for preparation of RNA further includes the steps of removing a RNA fragment cleaved by the DNAzyme by using an affinity column; and decomposing the DNAzyme with a DNA nuclease, and then removing decomposed DNAzyme fragments with a gel filtration column.