The London, Edinburgh and Dublin Philosophical Magazine and Journal of Science

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Taylor & Francis, 1920 - Physics
 

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Page 97 - Above a certain voltage, the intensity of any line per unit number of electrons reaching the anode attains a saturation value, in agreement with the quantum hypothesis which requires that the number of quanta radiated be proportional to the number of collisions, and hence (approximately) to the number of electrons present. Curves are given showing the relative intensities of the prominent caesium lines at various voltages. The ratio of intensities of the components of the first doublet of the principal...
Page 96 - The doublet 1.5 s — 2p, is alone produced under excitation of 1.5 to 3.9 volts accelerating field. The intensity of both of these lines gradually increases approximately proportional to the total number of electrons reaching the anode until the ionization potential is reached. At this point a pronounced decrease in intensity of these two lines occurs, amounting to the factor onethird. This decrease takes place at the voltage at which the...
Page 205 - The effect of a second group of the same or of a different kind is to decrease the effect of the first. Compare, for instance, toluene with xylene ; catechol, quinol, and cresol with phenol ; and methyl cyclohexanol with cyclohexanol. The simpler the group the more effective it is. Compare cymene with toluene or xylene, and benzyl alcohol with phenol. When the atoms are disposed with complete symmetry about a carbon atom, the result is a very bad lubricant, as we see in carbon tetrachloride and the...
Page 390 - There is now reigning in philosophy and in science an apathetic acquiescence in the conclusion that no coherent account can be given of nature as it is disclosed to us in sense-awareness, without dragging in its relations to mind. The modern account of nature is not, as it should be, merely an account of what the mind knows of nature; but it is also confused with an account of what nature does to the mind. The result has been disastrous both to science and to philosophy, but chiefly to philosophy.
Page 737 - BroekJ suggested that the nuclear charge might be equal to the atomic number of the element, ie the number of the element when all the elements are arranged in order of increasing atomic weight.
Page 93 - Logarithm of intensity of various caesium lines as a function of the applied exciting voltage volts and 3.0 volts. Neither can they be accounted for by velocity distribution due to temperature of the cathode. Thus the fractional number F of emitted electrons having a velocity greater by V0...
Page 97 - ... equal to 1.5 from 1.5 volts to 120 volts. The caesium arc of the type employed does not rectify alternating current of 1 20 volts. Sodium and potassium occurring as an impurity of the caesium similarly exhibited the single line or doublet spectrum 1.55 — 2p\, below their respective ionization potentials.
Page 96 - ... spectrum or above 2.7 volts in a group spectrum, rapidly approaches infinity as the accelerating potential in the arc is decreased. This ratio is 350 in a...
Page 737 - ... Rutherford* in 1911, has been confirmed by evidence gathered from such various sources that it now forms the foundation on which the development of atomic physics is based. On this theory, the positive charge associated with an atom is concentrated on a massive nucleus of small dimensions, surrounded by a distribution of electrons extending over a distance comparable with the diameter of the atom, as usually understood. The physical and chemical properties of an element are determined by the...

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