Internal sensoric effect

The installation of an additional position sensor is not always possible. Reasons may be costs and/or unavailable space. In this case, the internal sensoric effect displayed by some NiTiCu-alloys may be employed for indirect position sensing [84]. This leads to the use of a self-sensing actuator (cf. Sect. 6.9). In Fig. 6.58 the actuator length Ld of a NiTiCu shape memory wire is plotted against its electrical resistance Rd. The relation is free of hysteresis and is only slightly shifted by the actuators load. 

As self-sensing actuators, the internal sensoric effect can be used for position sensing (see Sects. 6.1.4 and 6.9). Again, this property is useful in small-sized applications where additional sensors cannot be accoimno-dated for space and weight reasons. 

Because of the experience gained in the Burro Series experiments, the downwind gas concentration sensor arrays were modified. This was based on the facts that beyond 400 m from the spill point the very low concentrations made the sensors of limited value and that close to the spill point, water and mud thrown up by RPT explosions had adverse effects on the sensors. Most of the open-path IR sensors for the measurement of LNG concentration were positioned at multiple levels on the downwind arrays between 140 and 400 m. In addition, some alternative sensors from International Sensor Technology and Mine Safety Appliance for measuring concentration were installed. 

Because of the wide range of the sensors, only four different sensor units are needed to cover the entire range of dp spans from 100 kN/m2 to 20 MN/m2 (4 in water to 3000 lb/in2) An internal temperature sensor monitors the temperature of the pressure sensor and is used to compensate the sensor output for the effects of temperature changes. The sensor temperature may also be transmitted digitally for monitoring, alarming, and for other appropriate applications. 

A number of promising C02 sensors have been described13,33. The phase-fluorometric system employing dual luminophore referencing, which is rather complex (two dyes, internal buffer system, sol-gel polymer matrix), has demonstrated satisfactory working characteristics33. But it still has to prove its safety and cost-effectiveness, and requires extensive validation with real food samples. 

Epoxy-based membrane of 2-[(4-chloro-phenylimino)-methyl]-phenol reveals a far Nemstian slope of 43 mV per decade for Pb+2 over a wide concentration range CIO 6 to 10 1 mol dm-3). The response time of the electrode is quite low (< 10 sec) and could be used for a period of 2 months with a good reproducibility. The proposed electrode reveals very high selectivity for Pb(II) in the presence of transition metal ions such as Cu2+, Ni2+, Cr and Cd2+at concentrations l.()xl() 3 M and 1.0><10 4 M. Effect of internal solution concentration was also studied. The proposed sensor can be used in the pH range of 2.50 - 9.0. It was used as an indicator electrode in the potentiometric titration of Pb+2 ion against EDTA. 

The sensors are available as a stand-alone entity for R D and development purposes and can be utilized with any network analyzer operating over the frequency range from 0.5 GHz to 10 GHz. KDC can also provides a cost-effective network analyzer with internal software to calibrate microwave parameters against process parameters. Custom design programs to meet specific applications can also be undertaken. Sensor costs are on the order of 3,000 KDC network analyzers cost approximately 24,000. 

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