Abstract: Top repairable gas-charged pulsation dampener designs include one or both of a threaded cover for bladder replacement and a standardized bladder with a double convex, anti-extrusion bladder button. The threaded cover, which speeds up bladder replacement over bolt-on covers, preferably has a two-piece construction to reduce torsion on the bladder neck. The bladder design, which includes a double convex, anti-extrusion bladder button, facilitates use of the same bladder design in both top repairable and bottom repairable gas-charged pulsation dampeners.

Abstract: A pulsed discharge helium ionization detector for gas chromatography with multiple combined bias/collecting electrodes.

Abstract: An apparatus for determining a resonant frequency of a wind turbine tower is provided. The apparatus includes a processing unit configured to receive an acceleration measurement value, the acceleration measurement value representative of the acceleration of the wind turbine tower in the direction parallel to a rotor rotational axis of the wind turbine and/or in the direction perpendicular to both the rotor rotational axis and the tower axis of the wind turbine. The apparatus includes a memory configured to store a series of acceleration measurement values, and the processing unit includes a Fourier transform module configured to calculate a spectral vector based on calculating a convolution-based fast Fourier transform of the series of acceleration measurement values, and includes a resonant frequency calculation module configured to calculate the tower resonant frequency based on the calculated spectral vector.

Abstract: A probe apparatus configured to measure a set of electrical characteristics in a plasma processing chamber, the plasma processing chamber including a set of plasma chamber surfaces configured to be exposed to a plasma is disclosed. The probe apparatus includes a collection disk structure configured to be exposed to the plasma, whereby the collection disk structure is coplanar with at least one of the set of plasma chamber surfaces. The probe apparatus also includes a conductive path configured to transmit the set of electrical characteristics from the collection disk structure to a set of transducers, wherein the set of electrical characteristics is generated by an ion flux of the plasma. The probe apparatus further includes an insulation barrier configured to substantially electrically separate the collection disk and the conductive path from the set of plasma chamber surfaces.

Abstract: New methods are used for detecting arcs in a plasma process that is fed by, for example, a freely oscillating AC generator with an output signal of the AC generator for supplying power. The method includes measuring or determining a reference value that is based on a time response of the output signal or of an internal signal of the AC generator relating to the output signal. The methods also include comparing the reference value with a threshold value and detecting an arc when a predetermined result of the comparison is obtained.

Abstract: Process for monitoring an alternating-voltage discharge between the electrodes of a double electrode and an apparatus. The process includes measuring values of at least one of a discharge current and a discharge voltage for each half-wave within an alternating-voltage discharge period, determining a difference between the measured values of a second half-wave and the measured values of the first half-wave, and comparing the determined differences to specific tolerance values. When the specific tolerance values are exceeded by the determined differences, a power supply is reduced, whereby the discharge is at least briefly suppressed. The apparatus includes a double magnetron including first and second targets arranged to form a double electrode, and a power supply coupled to supply power to the first and second targets.