Abstract: A method of preparing a carbon fiber including: preparing a precursor fiber for preparing a carbon fiber; and stabilizing the precursor fiber. The stabilization of the precursor fiber includes a first stabilization phase, a second stabilization phase, a third stabilization phase, and a fourth stabilization phase, which are set at four different temperatures between a temperature at which heat starts to be generated from the stabilization reaction of the precursor fiber and a temperature at which the generation of heat is maximized. Ozone gas is input while at least one phase of the third stabilization phase and the fourth stabilization phase is carried out.

Abstract: The present invention relates to a synthesis method of preventing the formation of impurities and byproducts in the synthesis of tenofovir disoproxil fumarate (Teno-DF) used as a medicine for hepatitis B and HIV treatment due to its function to promote bioactivities. In the synthesis method of the present invention, an ion-exchange resin (Dowex 50W hydrogen form, sulfonic acidic cation exchange resin) is used to enhance the yield and purity of the compound. The present invention also relates to a method of preparing an oral dissolving film dosage form in the manufacture of a medicine using the tenofovir compound with high purity obtained by the synthesis method of the present invention as an effective ingredient.

Abstract: Disclosed is a technique of diagnosing a state of a fuel cell system. The technique includes configuring a processor to calculate a duty ratio and an average output current, based on real-time driving data for a preset driving period, during operation of a fuel cell vehicle; obtain a reference current value from the calculated duty ratio and the calculated average output current; and determine a state of a fuel cell system by choosing a state graph corresponding to the obtained reference current value among a plurality of state graphs which vary depending on each reference current value.

Abstract: A system for a fuel cell vehicle is provided. The system includes an electrolytic cell installed to react residual hydrogen or oxygen within a stack when a fuel cell starts up and is shut down instead of an auxiliary resistor mounted on an exterior of a stack, thereby increasing stack durability. Particularly, the system for the fuel cell vehicle includes a stack unit of a fuel cell and an electrolytic cell unit configured to store energy in the form of hydrogen or oxygen.

Abstract: Disclosed is a technique of diagnosing a state of a fuel cell system. The technique includes configuring a processor to calculate a duty ratio and an average output current, based on real-time driving data for a preset driving period, during operation of a fuel cell vehicle; obtain a reference current value from the calculated duty ratio and the calculated average output current; and determine a state of a fuel cell system by choosing a state graph corresponding to the obtained reference current value among a plurality of state graphs which vary depending on each reference current value.

Abstract: Disclosed is a motor power simulating apparatus for fuel cell power module evaluation that accurately reflects real world characteristics of a fuel cell vehicle. More particularly, the power simulating apparatus disclosed herein includes a fuel cell power module, a ripple current generator, and an electronic load device, the ripple current generator connected to the fuel cell power module and the electronic load device to accurately simulate power output from a fuel cell of a fuel cell vehicle under real world conditions.

Abstract: Provided are a non-platinum oxygen reduction catalyst for a polymer electrolyte membrane fuel cell and a method for preparing the same. More particularly, an oxygen reduction catalyst in which chelated cobalt is impregnated on a conductive polymer coated on a carbon support and a method for preparing the oxygen reduction catalyst by coating a conductive polymer on a carbon support, impregnating chelated cobalt on the conductive polymer and then treating the same with heat and an acid are disclosed. The platinum-free oxygen reduction catalyst of the present invention has superior oxygen reduction activity and durability with high proportion of pyridinic and graphitic nitrogens on the catalyst surface, and thus can be usefully applied for a polymer electrolyte membrane fuel cell.

Abstract: The present invention relates to a process for preparing electrode catalyst materials for a polymer electrolyte membrane fuel cell (PEMFC), and particularly to a high-performance platinum-non-platinum mixed electrode catalyst (Pt—RuOs/C) having a physically mixed structure of RuOs alloy and platinum materials, which is prepared by adding a small amount of platinum (Pt) to RuOs alloy materials highly dispersed on a carbon support, where the amount of platinum used is drastically reduced as compared to the conventional platinum materials, thus lowering the manufacturing cost.

Abstract: The present invention relates to a method of activating membrane electrode assemblies of polymer electrolyte membrane fuel cells of a fuel cell stack for a vehicle comprising: supplying a humidified gas to a fuel cell so as to hydrate an electrolyte membrane and an electrolyte of electrodes of the fuel cell; and performing a cyclic voltammetry process so as to activate the layers of the electrodes.

Abstract: The present invention relates to a process for preparing electrode catalyst materials for a polymer electrolyte membrane fuel cell (PEMFC), and particularly to a high-performance platinum-non-platinum mixed electrode catalyst (Pt—RuOs/C) having a physically mixed structure of RuOs alloy and platinum materials, which is prepared by adding a small amount of platinum (Pt) to RuOs alloy materials highly dispersed on a carbon support, where the amount of platinum used is drastically reduced as compared to the conventional platinum materials, thus lowering the manufacturing cost.