Series switch plates

A scanning electronmicrograph of such a switch shows the series switch plate suspended over a microstrip transmission line, with a large actuation electrode located between the anchor and the series switch conductor (Fig. 4.2.6). Exaggerated sideview animations of the switch demonstrate the operation of the cantilever beam RF switch. 

In the schematic shown in Figure 4.2.10, the RF path is visible between the two signal sources (RF ports) used for extracting the S parameters, and is composed of a length of microstrip transmission line from each port connected to a model for a series-switch plate . Driven by the 6 mechanical wires at each side, which control its position, the switch plate is internally modeled as an equivalent circuit including transmission line, frequency-dependent resistance, and variable capacitance between the conductor on the plate and the underlap of the ends of the microstrip lines separated by the gap for the switch isolation. As with the beams, this model is defined by a complete set of parameters, such as the dimensions and material properties. Parameters can be adjusted quickly to achieve the desired RF performance for different closing states of the electromechanical structure. 

Coupled columns packed with different stationary phases can be used to optimize the analysis time (71, 75). In this approach the different columns are connected in a series or in parallel. liie sample mixture is first fractioned on a relatively short column. Subsequently the fractions of the partially separated mixture are separated on other columns containing the same or other stationary phases in order to obtain the individual components. Columns differing in length (number of theoretical plates), adsorptive strength or phase ratio (magnitude of specific surface area), and selectivity (nature of the stationary phase) can be employed, whereas, the eluent composition remains unchanged. Identification of the individual sample components via coupled column technique requires a careful optimization of each column and precise control of each switching step. 

At the end of a 30-min reaction period, the plasma was switched off and the feed of anhydrous ammonia gas was stopped. The propylene beads were evacuated for am additional 30 min to remove the unreacted species. The beads exposed to ammonia gaseous plasma are referred to as PPB-NH2. To characterize the surfaces of the control and the modified membranes, the FT-IR spectrometry ( Nicolet 7000 Series) with an ATR attachment was used. KRS-5 reflection plate at an incident angle of 45° was employed for FT-IR-ATR work. Control or modified membrane samples were applied on both sides of the reflection plate. Thi allowed spectra of only few micron thick layer of the surfaces contacting the KRS-5 reflection plate to be obtained. Immobilization of albumin onto membrane having surface amino groups has been described (2,3). 

I ourier transform mass spectrometers arc generally equipped with a trapped-ion analyzer cell such as that shown in Figure 20-18. Gaseous sample molecules arc ionized in the center of the cell by electrons that arc accelerated from the hlament through the cell to a collector plate. A pulsed voltage applied at the grid series as a gate to periodically switch the election beam on and off. The ions are held in the cell b a 1 to po-... 

In either version, cells of the bipolar type assembled to batteries of the filter-press t5q)e can be used. The version with circulating electrolyte is also feasible for building monopolar ( jai -type) cells that are cheaper than bipolar types (as they do not require expensive bipolar plates) and offer a highly flexible series-parallel switching within the battery to accommodate specific user needs. 

Fig. 66. Electric circuit for intermittent plate transport. Initiated by the pen carriage via a micro switch, with equal transport distances (pre-selected transport times). R8 connection to the micro switch. Coil A of a Siemens relay type 65404/ 93cT.rls 154d is in series with the micro switch and contact switches from position II to I this operates coil J5, likewise of a relay of the same type, closing contacts hi and 63 and opening This starts the cycle time, preselected with the potentiometer 0.1 M. At the end of the cycle, all contacts assume their original positions (61, 63 open, 63 closed) and a new cycle via micro switch ES can take place (circuit constructed by K. H. Haas, BASF, Ludwigshafen, W. Germany)...

---