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Electrical experiments

Dalton was a prolific scientist who made contributions to biology and physics as well as chemistry. At a college in Manchester. England, he did research and spent as many as 20 hours a week lecturing in mathematics and the physical sciences. Dalton never married he said once. "My head is too full of triangles, chemical properties, and electrical experiments to think much of marriage."... [Pg.28]

The pith was used by Native Americans as a moxibustion sort of treatment, where the herb is burned to cause heat on a particular part of the body. Modern-day biologists still use elder pith to hold scientific specimens as it can easily be sliced. The pith has also been used for electrical experiments and in toy making. The hollowed elder stalk has also been used as a smoking tube, especially for the inhalation of specific herbal medicines in both early America and Europe. [Pg.24]

No other method of electrification (other than by friction) had previously been known. After Hans Sloane had taken over the Presidency of the Royal Society in 1727, Gray belatedly began to receive the recognition that his electrical research deserved. He was awarded the Royal Society s first Copley Medal in 1731 for his discovery of conduction, and the second in 1732 for his work on electrostatic induction. Despite his electrical experiments, and a fondness for tobacco, he survived until 1736. He has no monument in stone, but is memorialized in verse by Dictionary Johnson (Samuel Johnson 1709-1784) [v]. He received the Copley Medal twice (in 1731 and 1732) and became FRS in 1733. [Pg.317]

Charge transport in the bulk has to obey electroneutrality. Figure 41 shows three simple experiments that comply with this restriction. For brevity let us call them the electrical (a), the tracer (b) and the chemical experiment (c) and, to be specific, let us consider an oxide. In the electrical experiment an electrical potential difference is applied, the electrons flowing in the outer circuit compensate the charge flow within the sample (Figure 41a shows this for the case of a pure ion conductor). If we apply reversible electrodes, in the steady state there is no compositional change involved. (At this point we are not interested in (electro-)chemical effects caused by non-reversible electrodes. This is considered in detail in Part II.1) The tracer transport (b) caused by the application of a chemical potential difference of the isotopes consists of a counter motion of the two isotope ions. Finally, experiment (c) presupposes a mixed conduction her the outer wire is, as it were,... [Pg.84]

If the bulk process is dominating, in the electrical experiment the total conductivity (ionic and electronic) is measured, the second gives information on the tracer diffusion coefficient (D ) which is directly related to the ionic conductivity (or DQ). In the third experiment one measures the chemical diffusion coefficient (D5), which is a measure of the propagation rate of stoichiometric changes (at given chemical gradient) it is evidently a combination of ionic and electronic conductivities and concentrations.3,4,173 175... [Pg.86]

This is of course also true if we need to consider the general electrochemical reaction Eq. (92). If the applied driving force (cf. electrical experiment) is an electrical potential gradient, Eq. (97) leads to the well-known non-linear Butler-Volmer equation.79 We will become acquainted with equally important kinetic equations for the cases of the tracer and the chemical experiment.172... [Pg.93]

In the pure electrical experiment we measure the conductivity which can be broken down into contributions of ions and electrons and finally into the defect contributions (k conduction electron, hole vacancy, interstitial)... [Pg.95]

Ref.205) this is not the case for a vacancy migrating in an electrical experiment, nor for an isotope in a tracer experiment moving according to an interstitial mechanism (Fig. 42 bottom). The relation between D and Dq then reads... [Pg.114]

In the tracer case [v ] is invariant and [00] is perturbed, while exactly the inverse is true for chemical diffusion (as long as [vo] [00]). The rate constants can also be considered to be invariant. However, in the electrical experiment, the latter are the variables of interest as they contain the driving force. Simplifying the... [Pg.139]

The unique nature of microwave power, as applied through matter to some reactant absorber, has increased the scope of our investigations to encompass more basic studies of the chemical—microwave interaction. The matrix component (shale, sand, etc.) of this interaction is being examined presently by electrical experiments and calculations (dielectric components, permativity, thermal capacity, and conduction). [Pg.341]

Experimentally, all the relaxation times are included between 100 sec and 5000 sec at the maximum of the elementary peaks (Tm). So, by analogy with dynamic electrical experiments, an equivalent frequency veq can be attributed to the TSC technique, i.e., 2nveq i(Tm) = 1 and veq 10 3 Hz. This low-equivalent frequency explains the high resolution of TSC and constitutes one of the most attractive features of the technique. Moreover, TSC permits the operator to perform a rapid characterization of materials and is an alternative approach to conventional dielectric techniques over this frequency range. [Pg.364]

Electrical experiments have shown that the TDDs with the highest ionization energies are metastable, with two different arrangements of the atoms. The... [Pg.227]

Battery/ This is the simplest and cheapest form of battery, and can be most readily made up In India. It is very powerful, fifteen cells being sufficient for all purposes of ignition, or for conducting electrical experiments in general. Two forms of this battery are shown in Figs. 6 and 6, the one being circular and the other square. Three cells of each kind are only shown, as they are quite sufficient for illustration. [Pg.44]

On the assumption that the same elementary quantum of electricity is concerned both here and in electrolysis (which can be verified approximately by experiment), we are led to the conclusion that the mass of these negative particles of electricity is about an 1830th part of that of a hydrogen atom. These carriers of negative electricity are called electrons and it can be shown, by optical and electrical experiments, that they exist as structural units in all matter. By making use of the fact that it is possible to produce on very small (ultra-microscopic) metal particles, and oil drops, a charge of only a few electrons, and to measure it, very accurate values have been found for the charge carried by an electron. Millikan found. ... [Pg.12]

To a good approximation, the more extensively studied azides are mostly ionic compounds with band gaps in excess of 3 eV, and they behave as insulators at room temperature. With such materials, it is not a simple matter to distinguish between contributions from ionic conductivity and electronic conductivity. Brief descriptions of the standard kinds of measurements appear below to point out some of the difficulties inherent in interpreting electrical experiments on ionic insulating materials. [Pg.235]

The present discussion [47] deals with the formation of natural self-assembly of CuS nanoclusters in dielectric substrates of gum Arabica biopolymer. Low concentration of ammonium complex of copper oxide solution was dissolved in gum Acacia Arabica solution at 60°C and stirred. H2S gas was passed in the same environment for 1 minute. Heating the resulting solution to about 100°C evaporates any possible trace of ammonia. The resulting nanocomplex was caste in the form of very thin film by spin coating technique. The developed specimen was used for experimental investigations, namely TEM, XRD, and electrical experiments such as impedance spectroscopy, and the Arrhenius plot and I-V characteristics were measured in the applied field direction perpendicular to the 2-D plane. [Pg.352]

In the middle of the nineteenth century, laboratory experiments demonstrated ever more clearly the great potential of electricity to be of help to people and to change fundamentally their everyday life. Gaston Plante was among the first to realise this and started investigations of various electrical phenomena. His experiments were very impressive. On 28 March 1858, he was chosen to demonstrate before Emperor Napoleon the Third and the Empress, in Palais de Tuileries, the principal electrical experiments that were known at that time [7]. [Pg.7]

L. GALVANI (1737-1798) publishes electrical experiments with frogs (1791) De Bononiensi Scientiarum et Artium Instituto atque Academia Commentarii VII 363, [Ostwalds Klassiker Bd 52 (1894)]... [Pg.339]

Desaguhers, J.T., 1739a. Several electrical experiments, made at various times, before the Royal Society, by the Rev. J. T. Desaguliers, LL. D. F. R. S. Philos. Trans. R. Soc. Lond. 41 (452 61), 661-667. Available at http //rstl.royalsocietypublishing.org/cgi/doi/10. 1098/rstl.l739.0114. [Pg.14]

Timothy J. Brennan (2001), The California Electricity Experience, 2000-01 Education or Diversion , http //www.rff.org/reDorts/PDF, files/3607BrennanCA.pdf Washington, D.C., Resources for the Future. [Pg.228]

John Chesshire (1996), UK Electricity Supply under Public Ownership, in The British Electricity Experiment—Privatisation The Record, the Issues, the Lessons (John Surrey, editor), London, Earthscan Publications. [Pg.228]


See other pages where Electrical experiments is mentioned: [Pg.388]    [Pg.394]    [Pg.395]    [Pg.103]    [Pg.3]    [Pg.233]    [Pg.77]    [Pg.10]    [Pg.84]    [Pg.100]    [Pg.400]    [Pg.86]    [Pg.133]    [Pg.134]    [Pg.136]    [Pg.139]    [Pg.20]    [Pg.610]    [Pg.23]    [Pg.84]    [Pg.16]    [Pg.238]    [Pg.142]    [Pg.163]    [Pg.305]   
See also in sourсe #XX -- [ Pg.82 , Pg.83 , Pg.84 , Pg.103 ]




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