Single wire probe

The wire-type sensor (probe) can be a single-wire construction, or it may have two or three separate wires. With a three-wire sensor, all three velocity components can be determined. As well as wire-type sensors, there are hot-... 

Fine deformed microstructures with strong preferred orientations could be produced by a single stroke of the wire probe (25), as illustrated by Figure 17. A vertical section made on a specimen quenched immediately after deformation confirmed that the underlying structure was fibrous with tt and 2tt wedge disclinations (30). The relaxation or coarsening after deformation indicated that the mesophase was sufficiently fluid for disclination motion... 

Figure 17 Formation and relaxation of deformed microstructure, after a single stroke by the wire probe on the hot stage (25). Crossed polarizers.

The probe is the heart of the NMR system. The most essential component is the RF transmitting and receiving coil, which is arranged to surround the sample holder and is tuned to the precession frequency of the nucleus to be measured. Modern NMR probes use a single wire coil to both excite the sample and detect the signal. The coil transmits... 

For a few experiments, single hot wire probes were mounted in the channel at different positions behind the grid to measure the flow velocity and the turbulence intensity in the unburned gas right in front of the flame. 

The SEMs of the sensors after metallization reveal the conductive nanowires formed between electrodes when a target biological is present. Figure 20.10 shows a test structure of target DNA hybridized to capture probes and Figure 20.11 shows a magnified view of a single wire (20 to 40 nm in diameter). 

An early measurement of current through a molecule was the report in 1995 of the resistance of a single C60 molecule, 1 (Fig. 6), deposited on an Au substrate and located and measured by an STM probe [59]. The conductivity was a respectable 18 nS. Most molecules studied as wires are more linear, with a coordinating atom at one or both ends. 

It is well known that contact between the bottom of the tip and the sample surface will not be between two smooth, regular surfaces. In particular, the bottom of the tip may contain many asperities, and one of these asperities will serve as the probe. In STM experiments the most common tip is made from a tungsten poly-crystalline wire, and other tip materials are commonly transition metals (platinum, iridium, alloys) [21]. It is generally agreed today that only a very sharp tip with a single atom at its pinnacle is suitable to obtain atomic resolution on close-packed surfaces. But, such a tip is highly unstable. Therefore, the fabrication and characterization of defined tips, e.g. by field ion microscopy, have not been achieved, nor can it... 

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