Abstract: The present invention relates to a paramagnetic polynuclear metal complex having enhanced self-relaxation rate and thermodynamic stability, and more particularly, to a synthetic method of a novel DTPA-bis-amide-histidine ligand and DTPA-bis-amide-aspartic acid ligand, a novel gadolinium complex ([Gd(L)H2O]) using the ligand, and a paramagnetic polynuclear metal complex using the gadolinium complex. The paramagnetic polynuclear metal complex is able to fix three or more metals (one gadolinium and two metal ions), thereby providing more excellent self-relaxation rate than the commercially available contrast agents. Thus, it can be widely applied to an MRI contrast agent because of meeting the high self-relaxation rate required as a contrast agent of magnetic resonance imaging (MRI).

Abstract: A method for producing a titanium dioxide photocatalyst is provided. The method uses a sol-gel process wherein acid and base catalysts are added in two separate steps. According to the method, a titanium dioxide photocatalyst with increased mesoporosity can be produced without the use of any particular additive. Further, an anatase structure is formed upon drying and is maintained even after high-temperature calcination. Further provided is a titanium dioxide photocatalyst produced by the method. Further provided is a titanium dioxide photocatalyst doped with sulfur and zirconium, which is produced by using the method. The doped titanium dioxide photocatalyst exhibits catalytic activity even under visible light and excellent surface characteristics to achieve improved photocatalytic activity.

Abstract: The present invention relates to a method of forming air holes in a hollow fiber membrane module for water treatment. A main object of the present invention is to easily form air holes in the potting material injected into the module housing to prevent contamination of the hollow fiber membranes in the module housing.

Abstract: A method for producing a titanium dioxide photocatalyst is provided. The method uses a sol-gel process wherein acid and base catalysts are added in two separate steps. According to the method, a titanium dioxide photocatalyst with increased mesoporosity can be produced without the use of any particular additive. Further, an anatase structure is formed upon drying and is maintained even after high-temperature calcination. Further provided is a titanium dioxide photocatalyst produced by the method. Further provided is a titanium dioxide photocatalyst doped with sulfur and zirconium, which is produced by using the method. The doped titanium dioxide photocatalyst exhibits catalytic activity even under visible light and excellent surface characteristics to achieve improved photocatalytic activity.

Abstract: The present invention relates to emitting compounds for organic electroluminescent device, particularly to phenyl pyridine-iridium metal complex compounds represented by the following formula (1): wherein R1 to R8, A1 to A3, and Py are as defined in the specification. In addition, the present invention relates to an organic electroluminescent device comprising the above material which has high luminescence efficiency, enhanced operating life time, and high purity of red chromaticity.

Abstract: The present invention relates to a polyvinylidene difluoride hollow fiber membrane and a method of preparing the same, and more particularly, to an improved polyvinylidene difluoride hollow fiber membrane and a preparation method thereof, in which a spinning solution consisting of polyvinylidene fluoride, alcohol dendrimer and organic solvent is prepared, and then is subjected to solidification by a wet-phase transition process, cleaning and drying, in which alcohol dendrimer that is an organic material as a pore former is introduced, allowing uniform disperse of alcohol dendrimer in polyvinylidene difluoride to form pores, with each having a high dispersion ability and a uniform size, and in which an excellent adhesion durability is imparted, owing to the use of a single material of polyvinylidene difluoride, unlike the conventional hollow fiber membrane preparation method in which pores are formed using existing inorganic particles.

Abstract: The present invention relates to emitting compounds for organic electroluminescent device, particularly to porphines-platinum metal complex compounds represented by the following formula (1): wherein R1 and R2 are as defined in the specification. In addition, the present invention relates to an organic electroluminescent device comprising the above material which has high luminescence efficiency, enhanced operating life time, and high purity of red chromaticity.

Abstract: The present invention relates to luminescence materials for an organic electroluminescent device (OELD), and particularly to phenyl pyridine-iridium metal complex compounds of formula (1), and preparation method thereof. In addition, the present invention relates to an organic electroluminescent device using the luminescence materials according to the present invention, which can greatly enhance the efficiency of luminescence and increase the operating life time of the device: wherein R1, R2 and R3 each are the same as defined in the specification.

Abstract: The present invention relates to emitting compounds for organic electroluminescent device, particularly to phenyl pyridine-iridium metal complex compounds represented by the following formula (1): wherein R1 to R8, A1 to A3, and Py are as defined in the specification. In addition, the present invention relates to an organic electroluminescent device comprising the above material which has high luminescence efficiency, enhanced operating life time, and high purity of red chromaticity.

Abstract: The present invention relates to emitting compounds for organic electroluminescent device, particularly to porphines-platinum metal complex compounds represented by the following formula (1): wherein R1 and R2 are as defined in the specification. In addition, the present invention relates to an organic electroluminescent device comprising the above material which has high luminescence efficiency, enhanced operating life time, and high purity of red chromaticity.

Abstract: The present invention relates to luminescence materials for an organic electroluminescent device (OELD), and particularly to phenyl pyridine-iridium metal complex compounds of formula (1), and preparation method thereof.