Abstract: A system for supplying liquefied hydrogen includes: liquefied hydrogen storage tanks each comprising a temperature control unit controlling an internal temperature of the liquefied hydrogen storage tank to maintain an inside of the liquefied hydrogen storage tank at a low pressure; pressure tanks receiving and storing liquefied hydrogen to be supplied to a liquefied hydrogen demand site from the liquefied hydrogen storage tanks, the pressure tanks having a smaller capacity than the liquefied hydrogen storage tanks and maintained at a higher pressure than the liquefied hydrogen storage tanks; a liquefied hydrogen supply line through which liquefied hydrogen is transferred from the pressure tanks to the liquefied hydrogen demand site; and a compressor compressing boil-off hydrogen gas generated in the liquefied hydrogen storage tanks and supplying the compressed boil-off hydrogen gas to the pressure tanks to generate a pressure required for delivery.

Abstract: The present invention relates to a method of preparing a symmetric or asymmetric cyclic phosphine compound, the method including a step of reacting a cyclic phosphine compound with an organic halogen compound under a predetermined coupling agent. The present invention provides a method of preparing a symmetric or asymmetric cyclic phosphine compound that uses cheaper compounds compared to a conventional method, has excellent economics by stably storing reaction raw materials, improves productivity and yield due to easy reaction control and low generation of by-products, is easily applied on an industrial scale, and has excellent expandability or substitutivity of a synthetic route.

Abstract: The present invention relates to a method of preparing an asymmetric phosphate-based compound. According to the method of the present invention, since a thiolane-based cyclic compound is used alone in a hydrophobic solvent under a base-free condition, the yield of a desired compound may be increased due to excellent reaction stability and reduced side reactions.

Abstract: The present invention relates to a method of preparing a symmetrical phosphate-based compound. According to the method of the present invention, since a dinucleating agent is used in a hydrophobic solvent under a base-free condition, the yield of a desired compound may be increased due to excellent reaction stability and reduced side reactions.

Abstract: The present application provides a hetero-cyclic compound which may significantly improve the lifetime, efficiency, electrochemical stability, and thermal stability of an organic light emitting device, and an organic light emitting device in which the hetero-cyclic compound is contained in an organic compound layer.

Abstract: The present application provides a hetero-cyclic compound which may significantly improve a service life, efficiency, electrochemical stability, and thermal stability of an organic light emitting device, and an organic light emitting device in which the hetero-cyclic compound is contained in an organic compound layer.

Abstract: The present application provides a hetero-cyclic compound which may significantly improve a service life, efficiency, electrochemical stability, and thermal stability of an organic light emitting device, and an organic light emitting device in which the hetero-cyclic compound is contained in an organic compound layer.

Abstract: The present application provides a hetero-cyclic compound which may significantly improve the lifetime, efficiency, electrochemical stability, and thermal stability of an organic light emitting device, and an organic light emitting device in which the hetero-cyclic compound is contained in an organic compound layer.