Wire loop electrode

Figure 5.27 Techniques for sealing platinum in soft-glass tubing (a) cylindrical wire electrode (b) wire-loop electrode.

In near-neutral dilute chloride solutions, concentrations of chromate, less than those suggested by Kaesche, have been observed to increase the pitting potential. Figure 6a shows anodic polarization curves from high purity A1 wire loop electrodes in deaerated 1.0 mM chloride solutions (25). Additions of 25 to 50 pM of sodium chromate were shown to elevate the pitting potential by hundreds of millivolts and reduce the passive current density by about a factor of 2. 

This elevation was attributed to the effect of chromate on metastable pitting. Figure 6b shows plots or current density versus time for high purity A1 wire loop electrodes potentiostatically polarized to -0.500 Wxe in the same solutions as those shown in Fig. 6a. As the chromate concentration is increased from 0 to 25 pM, and then from 25 to 50 pM, the metastable pit nucleation rate (events per unit time) diminishes, as does the magnitude of individual events (event peak current). The presence of chromate appears to decrease the metastable pit growth... 

The use of the wire loop electrode technique is important in these studies, as it is one means of ensuring against crevice attack that might compromise the integrity of the experimental findings. In such experiments, the working electrode... 

Partially immerse a fresh wire loop electrode in 1000 ppm NaCl solution. 

Fig.l Schematic representations of various masking techniques and sample configurations, (a) Flag electrode (b) wire loop electrode (c) sample painted with protective coating (d) sample mounted in epoxy or other metallographic mount. The wires for electrical... 

The experiments were conducted in a one-compartment cell with the reference electrode separated from the main compartment by a Luggln capillary and a closed electrolyte-wetted stopcock. The counter electrode was a gold wire loop and the reference electrode... 

Electrodes are made using heavy duty foil affixed to both ends of a microscope slide with a small (5 mm) gap in between. Wire loops are sandwiched between layers of each foil electrode. The wire loops can then be connected to the pulse generator. 

Figure 9.3 Stationary solution voltammetry cells, (a) Platinum wire loop auxiliary electrode, (b) reference electrode or reference electrode probe tip, (c) carbon paste working electrode, (d) graphite auxiliary electrode, (e) dropping mercury electrode, (0 platinum wire contact to mercury pool working electrode, (g) nitrogen gas inlet tube, (h) magnetic stirrer, (i) mercury pool working electrode, (j) glass frit isolation barrier.

The auxiliary electrode shown in Figure 9.3A and C is a platinum wire loop concentric with the working electrode. A platinum wire or foil, a mercury pool, and carbon can also be used for this purpose. The graphite rods used for emission spectroscopy are useful as auxiliary electrodes. For optimum performance at short times, the position of the reference probe might have to be changed from that shown when using different auxiliary electrodes. 

Electrodes Erlenmeyer Flask Power Supply/Battery Wire Loops... 

Green lead connect to the working electrode (302SS wire loop). 

A mechanically robust ECESR cell that is suitable for measurements even at very low temperatures with all kinds of electrolyte solvents and that employs a platinum wire loop as the working electrode located at the bottom of a 4 mm ESR cuvet has been developed by Fiedler et al. [618]. The reference and counter electrodes are placed above the working electrode outside of the sensitive region of the ESR cavity. 

Cables, wires, and connectors. Remedies light and flexible wires, carefully prepared wire tracks, and wire fixation with small wire loops allowing patient to move without wire pulling the electrode. Each electrode wire before leaving the body could be terminated in a small box, with common cable further from the body up to the electronic instrument. Tiny box with preamplifiers near the patient. Prewired electrodes are without the weight of local connector and plug. 

Fig. 6.30 The Curry wire loop encircling the free end of an electrode. (From Belott PH. Endocardial lead extraction A videotape and manual. Armonk, NY Futura Publishing, 1998, with permission.)...

FIG. 3—(a) Wire loop configuration for electrochemical testing, (b) flag electrode configuration for electrochemical testing. 

Figure 5.18 Scanning electron microscopy image of a microcantilever, electromachined into a stainless steel sheet by ultrashort voltage pulses (100 ns, 2 V, 1 MHz repetition rate) in 3 M HCI + 6 M HF. The tool electrode was a tiny loop of a 10 pm thick Pt wire. (Reproduced with permission from Ref. [80].)...

One of the first applications of the new mesh and node intramolecular circuit rules discussed above is the well-known problem in electrical circuit theory of the balancing of a Wheatstone bridge. In Fig. 21, a molecular Wheatstone bridge is presented, made of loop-like 4 tolane molecular wires bonded via benzopyrene end-groups for nano-pads 1 and 3, and via pyrene end-groups for nano-pads 2 and 4. This four-electrode and four-branch molecule is connected to a battery and an ammeter. 

---