| 摘要 |
PURPOSE:To simplify the mechanism of a moving section by controlling a stop valve provided at the mid-point of a conduit for introducing a liquefied gas to a sample part by a shape memory alloy and an electric heater near said alloy. CONSTITUTION:A liquefied gas vessel 3 contg. the liquefied gas 4 such as liquid nitrogen is provided in a vacuum vessel 1 and the liquefied gas conduit 6 is connected to the bottom thereof. A sample mounting part 6 having a bottomed cylindrical shape is formed to the lower part of the conduit 5 and a powder sample 8 is packed into the recess of a sample base 7 provided into said part. X-rays are projected to the sample 8 through X-ray windows 9, 10 and, for example, an X-ray diffraction angle is measured. A valve seat 14 having a hole 13 is formed in the conduit 5 and the valve 15 is disposed to the lower part thereof. The valve 15 is pressed by an open/shut pressing body 16 formed of the shape memory alloy which is expanded or contracted by the electric heater 20 in which current flows according to the sample temp. The inflow or shut off of the liquefied gas is thus executed. |
