Abstract: The present invention provides a method for water purification characterized in that a catalyst supporting iron and titanium oxide is mixed into the water to be treated containing suspended matter, and the suspended matter is adsorbed, decomposed, and precipitated, and the above-mentioned method for water purification is also characterized in that a catalyst supporting iron and titanium oxide and supported on a carrier is brought into contact with the wastewater or other water to be treated containing suspended matter, and the suspended matter is adsorbed, decomposed, and precipitated and further provides a water purifying agent produced by compounding an iron component with titanium oxide, and containing as an active component a catalyst supporting iron and titanium oxide, and a system thereof.

Abstract: A work holding apparatus is a work holder for holding a work in a predetermined position in relation to a basic member. A base column is rotatably supported astride on two sets of base plates. Holding fixtures are removably mounted on each side of the base column, such that different types of works can be supported and clamped by the holding fixtures. An indexing-rotation driving device rotates the base column such that it may be applicable to various types of works, thereby facilitating the holding of many types of works and the replacement of supporters and clamps. Furthermore, the base plate for supporting the base column is divided into two sets to reduce the weight of the base plate moving parts, and a base plate synchronizing means is provided to insure synchronized operation of the two base plates.