Abstract: According to an aspect of the invention, there is provided a method for detecting a target compound including: injecting a test liquid containing a target compound into a colloid solution of magnetic nano-particles having an average particle diameter of 50 nm or less to allow the target compound to bind to the magnetic nano-particles, thereby forming bound magnetic nano-particles having a diameter of 100 nm or more; and bringing a dispersion liquid containing the bound magnetic nano-particles in proximity to a magnetic sensor including at least a magnetoresistive (MR) element and a permanent magnet while measuring the change in magnetic resistance to selectively detect the bound magnetic nano-particles, thereby indirectly detecting the target compound.

Abstract: According to an aspect of the invention, there is provided a method for detecting a target compound including: injecting a test liquid containing a target compound into a colloid solution of magnetic nano-particles having an average particle diameter of 50 nm or less to allow the target compound to bind to the magnetic nano-particles, thereby forming bound magnetic nano-particles having a diameter of 100 nm or more; and bringing a dispersion liquid containing the bound magnetic nano-particles in proximity to a magnetic sensor including at least a magnetoresistive (MR) element and a permanent magnet while measuring the change in magnetic resistance to selectively detect the bound magnetic nano-particles, thereby indirectly detecting the target compound.

Abstract: A stirring apparatus for increasing processing speed and preventing deterioration of processing quality, includes a vessel having a predetermined number of liquid supply ports into which liquid to be stirred is made to flow; a liquid exhaust port from which liquid is discharged after stirring; stirring impellers separately arranged at two positions opposed to each other in the vessel, the stirring impellers being rotated in directions opposite to each other such that the liquid in the vessel is stirred; external magnets arranged outside the walls of the vessel close to the stirring impellers, the external magnets having magnetic couplings having no shafts which penetrate the vessel and connect with the stirring impellers; and external motors arranged outside the vessel, for driving the external magnets such that the magnets rotate the stirring impellers.

Abstract: An apparatus for supplying an accurately measured volume of liquid, comprising a vessel filled with the liquid, a cylinder loosely and slidably fitted into the vessel from above, and a sealing box at the top of the vessel sealing the vertical motion of the cylinder. The sealing box has a liquid discharge port at a bottom edge. A drive shaft, preferably screw driven, moves the cylinder vertically downward.

Abstract: The concentration of halogen ions in a photographic developer is controlled at an almost constant value by determining the concentration of halogen ions in the developer by detecting the change in electric potential caused by the addition of silver ions to the solution, and controlling the electrical current supplied to a halogen ion removing means, such as an electrodialysis or an electrolysis unit having an anion exchange membrane, based on the result of the determination of halogen ions. By this method the amount of complementary developer added to a fatigued developer solution can be greatly reduced.

Abstract: The concentration of halogen ions in a photographic developer is controlled at an almost constant value by determining the concentration of halogen ions in the developer by detecting the change in electric potential caused by the addition of silver ions to the solution, and controlling the electrical current supplied to a halogen ion removing means, such as an electrodialysis or an electrolysis unit having an anion exchange membrane, based on the result of the determination of halogen ions. By this method the amount of complementary developer added to a fatigued developer solution can be greatly reduced.