The present invention provides a process for preparing an isotope-containing phosphate compound easily. A user operates a specific key in the predetermined period of time, thereby allowing the user to return to a screen for editing the failed mail. The resilient member has a substantially cylindrical shape, defining a longitudinal slot so that end part thereof are separated from each other in order to have resiliency, and the bore being set so that an urging force is effected in a direction in which the outer periphery of the ornament chain is fastened when the ornament chains is inserted in the resilient member. and each of said at least one draw roller heated to a temperature greater than the temperature of said at least one feed roller and within the range of about 50 to about 150 C. A PIN type photodiode made by sequentially layering on top of the substrate a Si layer of a first conductivity type, a non-doped Ge layer and a Ge layer of a second conductivity type that is the opposite type of the first conductivity type and a Ge current-blocking mechanism is provided in at least part of the periphery of the PIN type photodiode.