Abstract: A fuel cell which can self-heat in a short time, in which no reaction gas is necessary for combustion, thereby improving the starting performance at low temperatures. The fuel cell comprises a cell structure in which an anode and a cathode are provided on either side of a solid polymer electrolyte membrane. This cell structure has a power generation plane and at least a part of the generation plane is defined as a local generation area so as to locally generate power. The fuel cell may include a pair of separators between which the cell structure is placed, and a reaction gas passage may be formed between the cell structure and each separator. One of a system for supplying a reaction gas to only a part of the reaction gas passage, and a system for supplying a reaction gas to the entire reaction gas passage is switchably selected.

Abstract: A fuel cell stack which comprises a plurality of unit fuel cells laminated via separators, and is connected to external resistors each allowing a feeble current to flow to each unit fuel cell, whereby such problems as an open-circuit voltage generation and corrosion that may be caused by fuel gas remaining after operation shutdown can be resolved. A switch is preferably attached in series with an external resistor.

Abstract: A fuel cell stack which comprises a plurality of unit fuel cells laminated via separators, and is connected to external resistors each allowing a feeble current to flow to each unit fuel cell, whereby such problems as an open-circuit voltage generation and corrosion that may be caused by fuel gas remaining after operation shutdown can be resolved. A switch is preferably attached in series with an external resistor.

Abstract: A fuel gas inlet is provided at an outer circumferential edge portion of a second separator. First fuel gas flow passage grooves for supplying a fuel gas to an anode electrode are formed on a side of a surface of the second separator. First fuel gas connecting flow passages, which make communication between the fuel gas inlet and the first fuel gas flow passage grooves, include flow passage grooves which are provided on a side of a surface, and through-holes which penetrate through the second separator to make communication with the first fuel gas flow passage grooves. Accordingly, excellent sealing performance is ensured with a simple structure, and it is possible to realize a thin-walled fuel cell.

Abstract: A fuel cell which can self-heat in a short time, in which no reaction gas is necessary for combustion, thereby improving the starting performance at low temperatures. The fuel cell comprises a cell structure in which an anode and a cathode are provided on either side of a solid polymer electrolyte membrane. This cell structure has a power generation plane and at least a part of the generation plane is defined as a local generation area so as to locally generate power. The fuel cell may include a pair of separators between which the cell structure is placed, and a reaction gas passage may be formed between the cell structure and each separator. One of a system for supplying a reaction gas to only a part of the reaction gas passage, and a system for supplying a reaction gas to the entire reaction gas passage is switchably selected.

Abstract: A stop method for a fuel cell system including a fuel cell unit in which hydrogen is supplied to an anode, and air is supplied to a cathode so as to generate electrical power via an electrochemical reaction. The stop method includes the steps of stopping supply of hydrogen to the anode, electrically connecting the anode and the cathode via an electrical load, and supplying air to the anode.

Abstract: An oxygen-containing gas flow field is formed on a surface of a first metal separator. The oxygen-containing gas flow field is connected between an oxygen-containing gas supply passage and an oxygen-containing gas discharge passage. The oxygen-containing gas flow field comprises oxygen-containing gas flow grooves, and ends of the oxygen-containing gas flow grooves are extended outwardly beyond ends of electrode catalyst layer of a membrane electrode assembly, and connected to an inlet buffer and an outlet buffer. When the purging process is performed at the time of stopping operation of the fuel cell, the purging air supplied to the oxygen-containing gas flow field discharges water retained in the electrode catalyst layers from the ends to the outlet buffer.

Abstract: Disclosed herein is a sensor utilizing attenuated total reflection. The sensor is constructed of a measuring chip, an optical system, and a measuring section. The measuring chip is equipped with a dielectric block, a thin film layer formed on the dielectric block, and a liquid-sample holding portion for holding a liquid sample. The optical system is used to make a light beam enter the dielectric block at various angles of incidence so that a total internal reflection condition is satisfied at an interface between the dielectric block and the thin film layer. The measuring section measures the state of attenuated total reflection, based on the intensity of the light beam totally reflected at the interface. The liquid-sample holding portion has an opening at its top surface. The sensor further has a lid supply mechanism for placing a lid on the opening to prevent evaporation of the liquid sample.

Abstract: A fluorescence observing apparatus including a light source for emitting excitation light, an excitation light irradiation section for irradiating the excitation light to a sample, and a fluorescence measurement section for measuring fluorescence emitted from the sample by the irradiation of the excitation light. In the fluorescence observing apparatus, a GaN semiconductor laser is employed as the light source.

Abstract: A method of operating a fuel cell assembly and a fuel cell system use a simple construction to restrain deterioration of power generating performance of a fuel cell assembly at a startup in a subfreezing environment. If an ignition switch is turned off is STEP 1, a control unit determines in STEP 3 whether the temperature of a fuel cell assembly (the internal temperature of the fuel cell assembly) is lower than a predetermined temperature, which is higher than the temperature at which the water produced during power generation freezes. If the internal temperature of the fuel cell assembly is the predetermined temperature or higher, then the processing proceeds to STEP 4 wherein a power generating condition is adjusted to cause the internal temperature of the fuel cell assembly to rise. In STEP 5, an alarm device is actuated.

Abstract: Evaluation of an amount of immobilized sample in a surface plasmon resonance (SPR) immunoassay is provided. To immobilize the sample, a sensor unit has a sensing surface. The sensor unit includes a transparent dielectric medium, and a metal film having the sensing surface. The metal film is connected with the dielectric medium for constituting a metal/dielectric interface. The sensing surface is adapted to sensing reaction of the sample. Then illuminating light reflected by the metal/dielectric interface is received with a photo detector such as a CCD upon applying the illuminating light to the metal/dielectric interface, to detect attenuation of the illuminating light and output a detection signal thereof. The evaluated amount of the sample immobilized on the sensing surface is evaluated according to the detection signal. Before immobilization, the sensor unit is tested for the photo detector to output an initial detection signal, which is considered for the evaluation.

Abstract: It is an object of the present invention to provide a method for simultaneously carrying out the detection or measurement of a substance interacting with a physiologically active substance immobilized on a biosensor and the analysis of the effects of the above substance on the biological activity of the physiologically active substance. The present invention provides a measurement method using a biosensor formed by immobilizing a physiologically active substance on a substrate, wherein the detection and measurement of a substance interacting with said physiologically active substance and the measurement of the biological activity of said physiologically active substance are carried out on said single biosensor.

Abstract: A plurality of fuel cells are stacked together. Current collectors are stacked on the fuel cells at opposite ends in a stacking direction of said fuel cells, and heating members are stacked on the outside of said current collectors. In a normal operating condition, electricity is delivered through the current collectors. When the temperature of end cells is lowered, a switching operation is performed to stop delivering electricity through the current collectors and start delivering electricity through the heating members.

Abstract: A fuel cell system includes a fuel cell. A current density measuring apparatus is provided on a cathode side of the fuel cell. The current density measuring apparatus includes a plurality of Hall elements provided at positions corresponding to measuring positions in an electrode surface. Each of the Hall element is attached to a ferrite core fitted to a pole of a sensor mounting plate. The ferrite core and the Hall element attached to the pole make up a current sensor.

Abstract: An analysis chip comprises a thin film layer, which is formed on a dielectric material block and has two different regions. A flow path unit comprising a supply path for supplying a sample onto the thin film layer and a discharging path for discharging the sample is releasably loaded into the analysis chip. A light beam is irradiated to a first interface between one region of the thin film layer and the dielectric material block, and a second interface between the other region of the thin film layer and the dielectric material block, in a parallel manner. Refractive index information with regard to a substance to be analyzed, which is located on the thin film layer, is acquired from intensities of the light beam totally reflected from the first interface and the light beam totally reflected from the second interface.

Abstract: A fuel cell system includes a fuel cell, an oxidant gas passage, a cathode off-gas passage, a fuel gas passage, a circulation passage, an anode off-gas passage, a fuel shutoff valve, a supply device, a humidifier and a control device. The supply device supplies a scavenging gas, which is for scavenging the fuel cell, to the anode and the cathode. The humidifier humidifies the scavenging gas. The control device controls the supply device when the fuel cell is turned off so that supply of the fuel gas to the anode is shut off and the scavenging gas is supplied to the anode and the cathode, wherein supply of the scavenging gas to the cathode is conducted through the humidifier.

Abstract: A system and method for draining remaining water in a gas passage of a fuel cell, which has a simple structure and the remaining can be efficiently and reliably drained outside. Water which remains in a gas passage of the fuel cell is first drained by increasing the flow rate of the reaction gas while the operation of the fuel cell is stopped. The remaining water which has not been drained is then drained by increasing the pressure of the reaction gas and then decreasing the increased pressure. The increase and decrease operation of the pressure of the reaction gas is started after the increase of the flow rate of the reaction gas is started. Typically, the increase of the pressure of the reaction gas is started when a predetermined time has elapsed after the increase of the flow rate of the reaction gas is started.

Abstract: A stop method for a fuel cell system including a fuel cell unit in which hydrogen is supplied to an anode, and air is supplied to a cathode so as to generate electrical power via an electrochemical reaction. The stop method includes the steps of stopping supply of hydrogen to the anode, electrically connecting the anode and the cathode via an electrical load, and supplying air to the anode.

Abstract: A stop method for a fuel cell system that includes a fuel cell unit in which hydrogen is supplied to an anode, and air is supplied to a cathode so as to generate electrical power via an electrochemical reaction. The stop method includes the steps of stopping supply of hydrogen to the anode, and supplying air to the anode so as to discharge water remaining at the anode.

Abstract: A fuel cell stack includes a plurality of unit cells stacked together. End cell stacks are disposed at opposite ends of the unit cells in the stacking direction. The unit cells between the end cell stacks are electrically connected in series. A first unit cell and a second unit cell in each of the end cell stacks are electrically connected in parallel by a cable. In each of the first and second unit cells a membrane electrode assembly is interposed between a first separator, and a second separator.