Abstract: A device for the reflection of low-energy ions defines an ion guide with an array of electrode elements elongated transversely to the direction of the ion beam and in closely spaced relationship with the alternating electrode elements having the same potential but opposite polarity.

Abstract: A caliper for soft objects such as tumor tissue has a pair of contact plates on respective members of which at least one is movable so that the object can be embraced between the contact plates. The instrument has a visual display of the contact pressure, an electrical display of the contact pressure or a locking mechanism establishing the contact pressure for reproducible measurement.

Abstract: A caliper for soft objects such as tumor tissue has a pair of contact plates on respective members of which at least one is movable so that the object can be embraced between the contact plates. The instrument has a visual display of the contact pressure, an electrical display of the contact pressure or a locking mechanism establishing the contact pressure for reproducible measurement.

Abstract: The total pressure of pure tritium or the partial pressure of tritium or another radioactive isotope depending upon the calibration is measured utilizing a cylindrical positive electrode, an axial central thin negative electrode coaxial with the cylindrical electrode and a source having a voltage up to 200 V connected in circuits of these electrodes. The circuit also includes a picoampere meter or a high ohmic resistance whose voltage drop is monitored by a digital volt meter so that currents of the order of picoamperes in the circuit can be detected and with appropriate calibration of the unit can provide an output which represents the pressure.