1" sensitivity sensors

A problem common to electrochemical cells is the analyzer can fail (degradation of the anode material and electrolyte or loss of sensor sensitivity), but still indicate a safe oxidant level when in reality it may not be so. Adherence to the manufacturer s recommendation as to how... 

We have to mention that the third type of adsorbents - monocrystalline oxides - is also feasible. From our stand-point their applicability domain deals with the studies of elementary stages of gas - solid body interaction, the results obtained being useful to manufacture sensors sensitive for specific gases. 

Fig. 5.8. Temperature dependence of ZnO sensor sensitivity to comparable concentrations of 2 (/) and 0(2)...

The coalescence of Au microcrystal in the islet film occurs during thermal annealing, as well as when the metal concentration is increased. It is probably the coalescence that does determine the above-mentioned loss of Au/ZnO-sensor sensitivity during high-temperature heating operations. 

Measures in UV reflectivity mode are thus possible, using a 400 nm peaked narrowband filter. However, because of the glass optics absorption below 400 nm and the low sensor sensitivity in the UV, the quality of the images in UV reflection mode is not particularly good, because of the long exposure time need for compensating the low illumination on the sensor. 

With regard to sensor sensitivity, Fig. 3.26 shows the wavelength shift and amplitude changes vs. chloroform concentration with quadratic interpolation for the 160 and 260 nm coated LPG compared with the uncoated one. As expected, without the sensing overlay negligible variations have been observed in both the measured parameters. Sensitivities of —0.130 nm/ppm and 0.163 dB/ppm were observed for the thinner in the range of 0 10 ppm. Sensitivities of —0.85 nm/ppm and 0.26 dB/ppm were measured for the thicker overlay, in the same range. 

Fig. 3.26 Sensor sensitivity for bare LPG, coated LPG with 160 nm and 260 nm sPS overlay...

More detailed analysis shows that the application of the low refractive index substrates not only increases the penetration depth into the cover media, but also since the mode profile is reversed places a larger portion of the electromagnetic power flowing in the waveguide structure into the cover media, thus increasing the sensor sensitivity for refractive index variations in the cover solution9 15. 

In recent years, rapid advancements in photonic technologies have significantly enhanced the photonic bio/chemical sensor performance, especially in the areas of (1) interaction between the light and analyte, (2) device miniaturization and multiplexing, and (3) fluidic design and integration. This has led to drastic improvements in sensor sensitivity, enhanced detection limit, advanced fluidic handling capability, lower sample consumption, faster detection time, and lower overall detection cost per measurement. 

Silicon hydrides, in growing amorphous silicon, 22 129-131 Silicon integrated circuits, 19 167 Siliconized coatings, 10 108 Silicon-killed free-machining steels, 24 424 Silicon lattice, 23 35 Silicon-manganese-zirconium, 26 638 Silicon microelectronics, sensor sensitivity and, 22 269... 

Adjusting the sensor sensitivity is usually only partially successful. There is another way to overcome the problem of false positives. A suite of sensors that are orthogonal in principle can be used together. 

Chapter 1, Chemical Sensing, introduces the subject with a general discussion of chemical sensing, exploring some of the possible avenues available. This chapter examines types and classes of sensing possibilities. It considers the required elements of a generic system and discusses the relationship of chemical concentration and sensor sensitivity. It includes a final section on the nomenclature of concentration and related issues. 

Sensor responses to 50 ppm of N0X in air are shown in Figure 5 for both Sn0x and PdAu/Sn0x sensors. The sensor resistance increases in the presence of N0X in air. The values of R(N0x)/R(air) are about 60 and 5 for Sn0x and PdAu/Sn0x sensors, respectively. While a PdAu deposit enhances the sensor sensitivity to alcohol vapor and some other hydrocarbon gaseous species, it depresses the sensor sensitivity to N0X. 

The use of genetically modified enzymes for the design of biosensors can be an effective way to improve the sensor sensitivity. 

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