Therefore, it is necessary to seek more effective methods to solve the problem of flow rate measurement in millimeter-scale pipes.Electrical conductivity is one of the basic physical parameters. Conductivity detection techniques have been adopted to implement flow rate measurements for many years and some achievements/progress have been obtained [12,13]. However, Perifosine mechanism the conventional conductivity selleck chemical detection technique for flow rate measurement is based on contact conductivity detection. The detection electrodes are directly in contact with the fluid. That will cause polarization effects and electrochemical erosion effects. Meanwhile, if the electrode has been contaminated, unpredictable measurement errors will arise.

Besides, the conventional conductivity detection techniques for flow rate measurement are used in normal scale pipes and few research Inhibitors,Modulators,Libraries works concerning Inhibitors,Modulators,Libraries the application of conductivity detection technique to the flow Inhibitors,Modulators,Libraries rate measurement in millimeter-scale pipes have been reported.Capacitively Coupled Contactless Conductivity Detection (C4D) is a new conductivity detection technique, which was independently proposed Inhibitors,Modulators,Libraries by Zemann et al., da Silva and do Lago, in 1998 [14,15], on the basis of Gas’ research work [16]. Compared with the conventional contact conductivity detection technique, C4D is a contactless detection technique and the electrodes of a C4D sensor are not in contact with the measured fluid. C4D can avoid the electrochemical reactions on the electrode surfaces and the polarization of the electrodes.

Meanwhile, C4D sensors are low cost and more robust [17�C20].

Inhibitors,Modulators,Libraries Unfortunately, C4D is still a developing technique. To date, C4D has mainly been studied and applied in the research field of analytical chemistry for Inhibitors,Modulators,Libraries ion concentration/conductivity detection in capillaries (the inner diameter Inhibitors,Modulators,Libraries GSK-3 is usually less than 0.2 mm) [14�C20]. Little research concerning the application of C4D to the flow rate measurement in millimeter-scale pipes has been reported [17�C19,21�C24].The aim of this work was to propose a new method for flow rate measurement in millimeter-scale pipes, combining the C4D technique and the principle of cross correlation flow measurement.

The research work included two steps: first, a new five-electrode C4D sensor, which was suitable for the flow rate measurement in millimeter-scale pipes, was developed.

Second, with two conductivity signals obtained sellckchem Inhibitors,Modulators,Libraries by the developed sensor, the flow rate measurement using the principle of cross correlation flow measurement was implemented. Meanwhile, experiments were carried out in five Drug_discovery millimeter-scale pipes with different inner diameters of 0.5, 0.8, 1.8, 3.0 Ceritinib side effects and 3.9 mm, respectively, to verify the feasibility and effectiveness of the proposed flow rate measurement method.2.?Five-Electrode C4D SensorFigure 1 inllustrates the principle of the C4D technique.