theory decrease velocity moving electrified von bohr niels (6 Ergebnisse)

(22 x 14,5 cm). VIII, 824 S. Mit Abbildungen und 18 teils gefalteten Tafeln. Halbleinwandband der Zeit. Erste Ausgabe. - Bohr beschreibt hier die Kathodenstrahlexperimente von Franck und Hertz mit Hilfe seiner Theorie, besonders den Übergang vom Normalzustand des Atoms in einen anderen stationären Zustand. "Die berühmten Stoßexperimente von Franck und Hertz wurden von Bohr sofort als Bestätigung der Existenz diskreter Energieniveaus aufgefaßt" (Röseberg, Bohr). - Stempel auf Titel. Einband gering berieben, sonst sauber und gut erhalten. - DSB 2, 239; Röseberg, Bohr Nr. 16 und 17. - Der Band enthält weiter Arbeiten von J. J. Thomson, Rayleigh, Bragg, Rutherford, Soddy etc.

In: The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science. Series 6 Vol. 25 = Januar-June 1913, No. 145, pp.10-31. Bound in half leather with gilt-stamped title on spine. Cover rubbed. Library stamps from Wilhelm von Siemens on title page and endpaper. Edges, endpaper and title page brown-spotted and a bit soiled. This is Niels Bohr's Seminal First Work on Nuclear Physics, the Foundation for his Atomic Theory. - Poggendorff V, 139. - The complete Volume includes 10 plates. VIII, 876 pp.- In this Volume are also included the following First Editions of: GEIGER, H. and E. MARSDEN, The Laws of Deflexion of Alpha Particles through Large Angles. No. 148, pp. 604-624. Poggendorff V, 418; MARSDEN, E. and H. RICHARDSON, The Retardation of Alpha Particles by Metals. No. 145, pp. 184-193. Poggendorff V, 810. Sprache: Englisch.

In: The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science. Series 6 Vol. 30 = July-December 1915, No. 177, pp. 394-415; No. 178, pp. 581-612. Bound in half leather with gilt-stamped title on spine. Edges rubbed and spine slightly torn. Library stamps from Wilhelm von Siemens on title page and endpaper. Edges, endpaper, title page and some plate margins are brown-spotted. Poggendorff V, 139. - The complete Volume includes 18 plates, VII, 824 pp.- In this Volume are also included the following First Editions of: THOMSON, J.J., Conduction of Electricity through Metals. No. 175, pp. 192-202. Poggendorff V, 1254; THOMSON, J.J., The Mobility of Negative Ions at Low Pressures. No. 177, pp. 321-328; THOMSON, J.J., A Method of Finding the Coefficients of Absorption of the Different Constituents of a Beam of Heterogeneous Röntgen Rays, or the Periods and Coefficients of Damping of a Vibrating Dynamical System. No. 180, pp. 780-783. RUTHERFORD, E., J. BARNES and H. RICHARDSON, Maximum Frequency of the X Rays from a Coolidge Tube for Different Voltages. No. 177, pp. 339-360; RUTHERFORRD, E. and J. BARNES, Efficiency of Production of X Rays from a Coolidge Tube. No. 177, pp. 361-367. Poggendorff V, 1083. RICHARDSON, O.W., Metallic Conduction. No. 176, pp. 295-299. Poggendorff V, 1046. Sprache: Englisch.

London, Taylor & Francis, 1913. 8vo. Bound in one nice contemporary half calf binding with gilt leather title-label to spine. Published in "The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science", Vol. 25. No. 145-150 offered. Small repair to spine and blind stamped to lower part of title page. The Bohr papers: pp. 10-31. [Entire volume: VIII, 876 pp.+ 10 plates]. Bohr's seminal first work on nuclear physics, being the work that lays the foundation for his atomic theory (published before his "On the Constitution of Atoms and Molecules"), in which he is able to conclude "that a hydrogen atom contains only 1 electron outside the positively charged nucleus, and that a helium atom only contains 2 electrons outside the nucleus ." "Bohr's 1913 paper on alpha-particles [i.e. the present], which he had begun in Manchester, and which had led him to the question of atomic structure, marks the transition to his great work, also of 1913, on that same problem. While still in Manchester, he had already begun an early sketch of those entirely new ideas." (Pais, p. 128). The present work must be considered one of the most important to the birth of modern atomic theory.After finishing his studies in Copenhagen, Bohr went to Cambridge in order to pursue his studies on electron theory under the guidance of J.J. Thompson. Thompson, who was beginning to lose interest in the subject by now, did, however, not recognize the genious of the young Bohr, and as soon as he could, Bohr went to Manchester, where Ernest Rutherford had established a laboratory. "There, from March to July 1912, working with utmost concentration, he [i.e. Bohr] laid the foundation for his greatest achievements in physics, the theory of the atomic constitution." (DSB). Bohr's survey of the implications of Rutherford's atomic model had led him to attack the much harder problem which lay at the core of it, namely determining the exact nature of the relation between the atomic number and the number of electrons in the atom. "Bohr obtained a much deeper insight into the problem by a brilliant piece of work, which he - working, as he said, "day and night" - completed with astonishing speed" (DSB), that paper being the present "On the Theory of the Decrease of Velocity of Moving electrified Particles on passing through Matter", which thus constitutes his very first publication on the subject, published immediately after this dense period of 1912, in the Philosophical Magazine of January 1913. "The problem was one of immediate interest for Rutherford's laboratory: in their passage through a material medium, alpha particles continually lose energy by ionizing the atoms they encounter, at a rate depending on their velocity. Their energy loss limits the depth to which the particles can penetrate into the medium, and the relation between this depth, or range, and the velocity offers a way of determining this velocity. What Bohr did was to analyze the ionizing process on the basis of the Rutherford model of the atom and thus express the rate of energy loss in terms of the velocity by a much more accurate formula than had so far been achieved-a formula, in fact, to which modern quantum mechanics adds only nonessential refinements" (DSB). In the present work, Bohr was thus able to conclude: "In this paper the theory of the decrease of velocity of moving electrified particles in passing through matter is given in a form, such that the rate of the decrease in the velocity depends on the frequency of vibration of the electrons in the atoms of the absorbing material." as well as the seminal words that have been formative for the birth of the modern atomic theory: "Adopting Prof. Rutherford's theory of the constitution of atoms, it seems that it can be concluded with great certainty, from the absorption of alpha-rays, that a hydrogen atom contains only 1 electron outside the positively charged nucleus, and that a helium atom only contains 2 electrons outside the nucleus ". Bohr continues: "These questions and some further information about the constitution of atoms which may be got from experiments on the absorption of alpha-rays, will be discussed in more detail in a later paper." (pp. 30-31 of the original paper) - the last sentence referring directly to his three part "On the Constitution of Atoms and Molecules", in which he went on to present his postulates of the orbital structure of the electrons and their quantized radiation. Rosenfeld, Bohr Bibliography No. 5. Rosenfeld, Dictionary of Scientific Biography II, pp. 240-41. Pais, Niels Bohr's Times, pp. 117-31.

London, Taylor & Francis, 1915. Contemp. hcalf. Spine gilt, title- and tomelabels with gilt lettering. Spine a bit rubbed, some cracking to hinges, but covers not detached. In: "The London, Edinburgh, and Dublin Philosophical Magazine and Journal of Science", Vol. XXX, Sixth Series. VIII,824 pp., textillustr. and 18 plates. (Entire volume offered). Bohr's papers: pp. 394-413 and pp. 581-612. A stamp to verso of titlepage. Internally clean and fine. First appearance of a landmark paper in which Bohr found experimental support for his energy equation for electron orbits and of stationary states in the work of Franck and Hertz from 1914. Furthermore, Franck and Hertz unwittingly provided an independent confirmation of the concept of stationary state. In 1914 they observed an energy threshold in the electron-stopping power of mercury vapor. This threshold, Bohr explained the following year, corresponded to a transition between the normal state and another (first excited) stationary state of the mercury atom (and not, as Franck and Hertz had originally thought, to the ionization of the atom). The supramechanical stability implied by the assumption of stationary states was now empirically proved to comprehend stability with regard to electron impacts."Bohr had to frequently revise and refine his atomic model in light of new discoveries. One significant paper "On the Quantum Theory of Radiation and the Structure of the Atom," (the paper offered) added more specific details about atomic states. For example Bohr had earlier made the argument that electrons could jump from one orbit to another as energy was emitted or absorbed. In this paper, he theorezed that an atom possesses stationary states in which energy was neither emitted nor absorbed. Any emission or absorption that did occur, such as might induce an electron ump, would correspond to the transition between two stationary states."(sparknotes.com).An: the second paper offered. When Bohr had finished his importent paper on the hydrogen atom "On the Theory of Decrease of Velocity of Moving Electrified Particles on passing through Matter" 1913, he completed another paper on that subject (the paper offered), which includes the influence of effects due to relativity and to straggling (that is, the fluctuations in energy and in range of individual particles).(Pais p. 128).Rosenfeld no 13 a. 14.The volume contains further importent papers by J.J. THOMSON, W.H. BRAGG, RUTHERFORD & BARNES, SODDY & HITCHINS etc.

London, Taylor & Francis, 1913. 8vo. Original printed wrappers" chipped, backstrip lacks. The whole issue. 200 pp., 2 plates. First edition of Bohr's first work on nuclear physics, published just before his 'On the Constitution of Atoms and Molecules'. During his visit to Manchester Bohr had the chance to get a first hand account of Rutherford's investigations on the penetration of alpha-particles through matter. In order to explain the large-angle scattering of alpha rays, which Rutherford had observed, he proposed his "nuclear" model of the atom in contrast to J.J. Thomson's "plum pudding" model in 1910. Bohr eagerly took up the new model and soon recognized its far-reaching implications. In particular, he pointed out that the nuclear model of the atom implied a sharp separation between the chemical properties, ascribed to the peripherical electrons, and the radioactive properties, which affected the nucleas itself. In this paper the theory of the decrease of velocity of moving electrified particles in passing through matter is given in a form, such that the rate of the decrease in the velocity depends on the frequency of vibration of the electrons in the atoms of the absorbing material. In the conclusion Bohr could state 'that a hydrogen atom contains only 1 electron outside the positively charged nucleas, and that a helium atom only contains 2 electrons outside the nucleas'.Rosenfeld, Bohr Bibliography No. 5. Rosenfeld, Dictionary of Scientific Biography II, pp. 240-41.