Reflectance voltage curve

A d.c. insulation resistance test or polarization index reveals only the surface condition of the insulation and does not allow a realistic assessment of internal condition. Loss tangent values are true reflections of the insulation condition to detect moisture content, voids, cracks or general deterioration. The tan 5 versus test voltage curve may be drawn and compared with the original curve provided by the manufacturer, and inferences drawn regarding the condition of the insulation. The different starting tan lvalues will reveal the condition of the insulation in terms of amount of contamination, as noted in Table 10.4 (See lEE, Vol. 127, May 1980). 

Fig. 16 Photocurrent-voltage curve of a solar cell based on complex 26. The cell was equipped with an anti-reflective coating. The conversion efficiency in full AM 1.5 sunlight illumination (100 mW cm-2) is 11.18%. The cell is masked with black plastic to avoid the diffusive light leaving an active cell area of 0.158 cm2...

Once some Ce + is added, Fe " and Ce " are generated by the chemical redox reaction, and the current-versus-voltage curves for the test solution now have components reflecting the reduction of Fe + and oxidation of Ce +, as shown in Figure 3.20B. The A shifts along the current-versus-voltage curve to the point where the... 

An STM probe has been used to isolate individual MS (M = Cd, Pb) particles and to measure electronic phenomena (55,56,81). The MS films were prepared either by exposure of metal ion/fatty acid films to H2S (55,56) or by transfer of a compressed DDAB-complexed CdS monolayer (81). All the films were transferred onto highly oriented pyrolytic graphite (HOPG) for the STM measurements. A junction was created at an individual CdS particle with the STM tip as one electrode and the graphite as the other, and the current/voltage characteristics of the panicles were measured. For the particle prepared in the fatty acid films the I/V curves exhibit step-like features characteristic of monoelectron phenomena. In the case of the DDAB-coated CdS particles the I/V measurements demonstrated n-type semiconductor behavior. The absence of steps in this system is probably a reflection of the larger size of the particles in the DDAB films (8 nm by AFM) compared to the 2-nm particle size typically found for MS particles formed in fatty acid films. 

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