Water moisture detector

Water-Cooled motors, type CACW (cooling type ICW 37 A 81 or ICW 37A 91) (Section 1.16, Table 1.12) should be fitted with moisture detectors to provide an audio-visual alarm in the event of a leakage in the water circuit or a higher coolant temperature. 

The bridging polymer is a conducting poly(3-methyIthiophene) or polyaniline and the solid state redox conduction between all electrodes is accomplished by a common coating with poly(ethyleneoxide)/Li" CF3S03- or poly(vinyl alcohol)/ The polyaniline based molecular transistor proved as a very sensitive moisture detector it works well in a dry argon atmosphere but in water saturated argon the device cuts out... 

Photometric Moisture Analysis TTis analyzer reqiiires a light source, a filter wheel rotated by a synchronous motor, a sample cell, a detector to measure the light transmitted, and associated electronics. Water has two absorption bands in the near infrared region at 1400 and 1900 nm. This analyzer can measure moisture in liquid or gaseous samples at levels from 5 ppm up to 100 percent, depending on other chemical species in the sample. Response time is less than 1 s, and samples can be run up to 300°C and 400 psig. 

Two different types of information can be obtained by bombarding soil with neutrons. Fast neutrons are slowed when they interact with water and thus can be used to measure the amount of water present. This type of analysis is most often conducted in the field rather than in the laboratory. Figure 8.2 illustrates the use of a fast neutron source and a slow neutron detector to measure the moisture content of soil. This method depends on the interaction of neutrons with hydrogen and so it is not as useful in soils with significant or highly variable organic matter contents. 

One of the keys for generating reproducible data is to consider a system s lower detection limit and the upper limits for linear detector response (Beer s law). For instance, coulometric moisture analysis is accurate for samples containing 10 (Xg of H20. Injection of a particularly dry sample may deliver <10 xg of H20,in which case the amount of water measured may not be accurate. Similarly, injecting a dilute sample aliquot may not allow the detection of an impurity present at low levels, so a more concentrated sample preparation may be required. The analysis of a sample preparation more concentrated than those routinely prepared may give detector area count responses beyond the linear response for that compound, making the calculated concentration lower than the true concentration. The injection of a highly concentrated sample may also saturate the detector... 

It is a fundamental requirement that liquefied petroleum gas should not contain free water (ASTM D-2713). Dissolved water may give trouble by forming hydrates and giving moisture vapor in the gas phase. Both of these will lead to blockages. Therefore, test methods are available to determine the presence of water using electronic moisture analyzers (ASTM D-5454), dew-point temperature (ASTM D-1142), and length-of-stain detector tubes (ASTM D-4888). 

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