Electrically Active Paper

A novel composite paper was fabricated by Luong et al. [61] out of nanofibrillated cellulose (NFC) and PolyaniHne (PANi) through in-situ polymerization technique. The synthesized materials exhibited high electrical conductivity and good mechanical characteristics and can be explored for various electrically active apphcation areas. 

NFC/PANi composite formed by vacuum filtration or casting 

The FTIR and XPS analysis showed that site-interaction between NH and OH groups of PPy and BC components, respectively, was operative in both the composites. The affinity between functional groups of PPy-FeClj and BC was higher than that found for BC/PPy-APS composite. In addition, the tensile properties (tensile strength 40 MPa) were also influenced by the chemical affinity of both the components in the composites [62]. 

The main thermal degradation parameters, PPy content estimated by thermogravi-metric analysis (TGA) and electrical conductivity of pure BC and composites are given in Table 5.4. 

Samples Py content (mol L ) Onset temp. (°C) Residue (%) PPy content (%) Electrical conductivity (S cm ) 

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The original view that the mechanism of activation is mainly due to electrostatic fields between the active patches and the specifically fitting adsorbed molecules, appears rather too simple at the present time the reader should consult the original papers (a, f) for details. Whatever be the mechanism, an electrical activation of a simple nature, or an elaborate quantum mechanical deformation, it is certainly fairly specific, and its further investigation should yield a rich reward, and be perhaps no more difficult than the investigation of the mechanism of activation by inorganic catalysts. In the case of these more complex catalysts, one has the weapon of a controlled variation of chemical constitution, which is not always readily available for researches on inorganic catalysts. 

In the present paper our previous analysis of fluidized bed filtration efficiencies has been extended by considering more realistic methods for estimating the single collector efficiencies as well as more recently reported experimental results. In general the predicted values of the fluidized bed filtration efficiencies compare favorably to the experimental values. For electrically active fluidized beds, direct measurements of the particle and collector charges would be necessary to substantiate the results given here. 

Today the number of electroactive polymers has grown substantially. There currently exists a wide variety of such materials, ranging from rigid carbon-nanotubes to soft dielectric elastomers. A number of reviews and overviews have been prepared on these and other materials for use as artificial muscles and other applications [1, 2, 7, 10, 11, 13-28]. The next section will provide a survey of the most common electrically activated EAP technologies and provide some pertinent performance values. The remainder of the paper will focus specifically on dielectric elastomers. Several actuation properties for these materials are summarized in Table 1.1 along with other actuation technologies including mammalian muscle. It is important to note that data was recorded for different materials under different conditions so the information provided in the table should only be used as a qualitative comparison tool. 

C.R. Johnson, R.S. MacLeod, and M.A. Matheson. Computer simulations reveal complexity of electrical activity in the human thorax. Comp. Phys., 6(3) 230-237, May/June 1992. This paper deals with the computational and visualization aspects of the forward ECG problem. 

Jerman H (1990) Electrically-activated, micromachined diaphragm valves. Paper presented at the 1990 solid... 

The role of inherent polarization and ionic transport effects in actuation mechanism of EAPap actuators are investigated. To physically investigate the actuation mechanism, several tests are performed. X-ray diffraction (XRD) spectra are compared before and after electrical activation and the possibility of crystalline structure change is observed. Dielectric property measurement indicates a dependence of the dielectric constant on fiber direction, as well as on frequency, humidity, and temperature. Thus, we conclude that piezoelectric effect and ionic migration effect are in the EAPap at the same time associated with dipole moment of cellulose paper ingredients. The amount of these effects may depend on environmental condition. 

ANS The sequence of activation is generally received by the formulation that Dr. Geselowitz used in his paper. The main difference is in the production of those potentials, i.e., the laws of the propagation of the electrical activity through the conduction system and myocardial cells. 

This test essentially consists of displaying the electrical activity of a living muscle using an intramuscular wire electrode which is placed transcutaneously on the intended muscle. This signal can be converted into a sound and played to a loudspeaker it can be stored on magnetic tape or printed out using electronic printer or light-sensitive paper. 

The recorder-transmitter converts cardiac electrical activity to acoustic waves and sends them through a telephone line to a receiver, which converts the waves and records them on ECG paper. 

Asbestos fibers have also been widely used for the fabrication of papers and felts for flooring and roofing products, pipeline wrapping, electrical insulation, etc. Asbestos textiles, comprising yam, thread, cloth, tape, or tope, also found wide apphcation in thermal and electrical insulation, friction products in brake or clutch pads, etc. In recent years, some of these appHcations have decreased to various extents, although others remain fairly active, typically in friction materials. 

We can determine an approximate value of the pH of an aqueous solution very quickly with a strip of universal indicator paper, which turns different colors at different pH values. More precise measurements are made with a pH meter (Fig. 10.11). This instrument consists of a voltmeter connected to two electrodes that dip into the solution. The difference in electrical potential between the electrodes is proportional to the hydronium ion activity (as will be explained in Section 12.10) so, once the scale on the meter has been calibrated, the pH can be read directly. 

Abstract In this paper the synthesis, properties and applications of poly(organophos-phazenes) have been highlighted. Five different classes of macromolecules have been described, i.e. phosphazene fluoroelastomers, aryloxy-substituted polymeric flame-retardants, alkoxy-substituted phosphazene electric conductors, biomaterials and photo-inert and/or photo-active phosphazene derivatives. Perspectives of future developments in this field are briefly discussed. 

Fig. 2 shows the temperature as a function of irradiation time of Cu based material under microwave irradiation. CuO reached 792 K, whereas La2Cu04, CuTa20e and Cu-MOR gave only 325, 299 and 312 K, respectively. The performances of the perovskite type oxides were not very significant compared to the expectation from the paper reported by Will et al. [5]. This is probably because we used a single mode microwave oven whereas Will et al. employed multi-mode one. The multi-mode microwave oven is sometimes not very sensitive to sample s physical properties, such as electronic conductivity, crystal sizes. From the results by electric fixmace heating in Fig. 1, at least 400 K is necessary for NH3 removal. So, CuO was employed in the further experiments although other materials still reserve the possibility as active catalysts when we employ a multi-mode microwave oven. 

Electrokinetic processes are widely used in different fields of science and technology. We had already mentioned the use of electrokinetic processes for research into the electric properties of surface layers of insulating materials. Such measurements are used, in particular, when studying the surface properties of polymeric materials, their behavior in different media, and their interactions with other materials (e.g., with adsorbing surface-active substances). The results of this research are used in textile, cellulose and paper, and other industries. 

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