correct microscope
1.The factores effecting on properties of eletron gun of H - 700 transmission electron microscope were studied and corresponding measures were taken. It is found that spraying freon is a good method for vaccum leak detecting. With the maintaining by the correct method, the vacuum inside the high - voltage electron gun was kept at 1.33 × 10-3Pa, and the lifetime of the filament was remarkably prolonged.
