Results for 'atomic orbital'

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  1.  16
    Nature of Atomic Orbits.Nikolay Dibrov - 2011 - Apeiron: Studies in Infinite Nature 18 (4):352.
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  2.  69
    The recently claimed observation of atomic orbitals and some related philosophical issues.Eric R. Scerri - 2001 - Proceedings of the Philosophy of Science Association 2001 (3):S76-.
    The main thrust of the paper involves a theoretical and philosophical analysis of the claim made in September 1999 that atomic orbitals have been directly imaged for the first time. After a brief account of the recent claims the paper reviews the development of the orbit and later orbital concepts and analyzes the theoretical status of atomic orbitals. The conclusion is that contrary to these claims, atomic orbitals have not in fact been observed. The non-referring nature (...)
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  3.  27
    The Recently Claimed Observation of Atomic Orbitals and Some Related Philosophical Issues.Eric R. Scerri - 2001 - Philosophy of Science 68 (S3):S76-S88.
    The main thrust of the paper involves a theoretical and philosophical analysis of the claim made in September 1999 that atomic orbitals have been directly imaged for the first time. After a brief account of the recent claims the paper reviews the development of the orbit and later orbital concepts and analyzes the theoretical status of atomic orbitals. The conclusion is that contrary to these claims, atomic orbitals have not in fact been observed. The non-referring nature (...)
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  4.  16
    On the calculation of the Compton profiles of crystals using linear combinations of atomic orbitals.O. Aikala - 1975 - Philosophical Magazine 31 (4):935-942.
  5.  33
    Group theory and orbital fluctuations of the hydrogen atom.H. Kleinert - 1993 - Foundations of Physics 23 (5):769-807.
    We review some of the progress made in the past 27 years in understanding the group theoretic and path integral aspects of the hydrogen atom. The group theoretic development was triggered by A. O. Barut who suggested to me the search for a dynamical group larger than SO(4). In this way he became indirectly responsible also for important recent path integral developments.
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  6.  14
    Charles S. McCaw: Orbitals with applications in atomic spectra, 2nd edition.Eric R. Scerri - 2020 - Foundations of Chemistry 23 (1):133-134.
  7.  56
    Have orbitals really been observed?Eric R. Scerri - 2000 - Journal of Chemical Education 77:1492-1494.
    The article disputes the recent claim featured in "Nature" magazine and many other science magazines to the effect that atomic orbitals have been observed for the first time. The claim is incorrect in view of the unconvincing nature of the evidence adduced and since atomic orbitals are deemed unobservable in principle by quantum mechanics. In addition, the possible educational drawbacks of this incorrect claim are discussed.
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  8.  13
    Charles S. McCaw: Orbitals with applications in atomic spectra, 2nd edition: World Scientific Press, Singapore, 2020. [REVIEW]Eric R. Scerri - 2020 - Foundations of Chemistry 23 (1):133-134.
  9.  29
    Atomic mechanism of the Re and Ru strengthening effect on the γ-γ′ interface of Ni-based single-crystal superalloys: A first-principles study.K. Chen, L. Zhao & John Tse - 2003 - Philosophical Magazine 83 (14):1685-1698.
    A possible atomic mechanism underlying the Re- and Ru-induced strengthening effects on the n - n ' interface in Ni-based single-crystal superalloys has been investigated using the DMol3 molecular orbital package based on density functional theory. The calculation of bonding properties has been performed on a cluster designed to model Re and Ru strengthening effects within the interface. The stronger Re--Ni bonds are formed mainly as a result of d- hybridization, while the Ni--Ni bonding become weaker accompanying the (...)
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  10.  59
    Unconventional Approach to Orbital-Free Density Functional Theory Derived from a Model of Extended Electrons.Werner A. Hofer - 2011 - Foundations of Physics 41 (4):754-791.
    An equation proposed by Levy, Perdew and Sahni (Phys. Rev. A 30:2745, 1984) is an orbital-free formulation of density functional theory. However, this equation describes a bosonic system. Here, we analyze on a very fundamental level, how this equation could be extended to yield a formulation for a general fermionic distribution of charge and spin. This analysis starts at the level of single electrons and with the question, how spin actually comes into a charge distribution in a non-relativistic model. (...)
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  11.  14
    Orthogonality properties of states, configurations, and orbitals.Balakrishnan Viswanathan & Mohamed Shajahan Gulam Razul - 2022 - Foundations of Chemistry 24 (1):73-86.
    This manuscript explores the orthogonality constraints on configurations and orbitals subject to the property that states are mutually orthogonal. The orthogonality constraints lead to properties that affect the description of chemical systems. When states are described as linear combinations of configurations, the coefficient matrix diagonalises S−1H. Therefore, single-configuration states are only possible in one-electron systems: non-orthogonal configurations yield single-configuration states only if S−1H is diagonal, but this would violate the orthonormalisation constraint. Further, the coefficient matrix is not constrained to be (...)
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  12.  10
    Response to Geoffrey Neuss on how to teach the 4s and 3d orbital conundrum.Eric Scerri - 2021 - Foundations of Chemistry 23 (2):247-251.
    In the accompanying article in this issue Neuss challenges the explanation that was first suggested by Schwarz for how to teach the relative occupation and ionization of atomic orbitals in the atoms of metals in the first transition series. The present article is a response to Neuss’ critique which includes a detailed examination of his claim that there is no conclusive evidence for the view that the scandium and other first transition metal atoms lose 4s electrons in preference to (...)
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  13. Relating screening to atomic properties and electronegativity in the Slater atom.Balakrishnan Viswanathan & M. Shajahan Gulam Razul - forthcoming - Foundations of Chemistry:1-25.
    Slater’s method is an integral part of the undergraduate experience. In actuality, Slater’s method is part of an atomic model and not simply a set of rules. Slater’s rules are a simple means for computing the effective nuclear charge experienced by an orbital. These rules are based on the shell-like structure of the Slater atom in which outer shell electrons are incapable of shielding inner electrons. Slater’s model provides a qualitative description of the valence electrons in multi-electron atoms (...)
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  14. Soliton model of atom.Yu P. Rybakov & B. Saha - 1995 - Foundations of Physics 25 (12):1723-1731.
    The Einstein-de Broglie soliton concept is applied to simulate stationary states of an electron in a hydrogen atom. According to this concept, the electron is described by the localized regular solutions to some nonlinear equations. It is shown that the electron-solilon center travels along some stationary orbit around the Coulomb center. The electromagnetic radiation is absent as the Poynting vector has non-wave asymptote O(r −3)after averaging over angles.
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  15.  63
    Using logic to define the Aufbau–Hund–Pauli relation: a guide to teaching orbitals as a single, natural, unfragmented rule-set. [REVIEW]Conal Boyce - 2012 - Foundations of Chemistry 16 (2):93-106.
    The general chemistry curriculum includes a prelude that consumes nearly all of the first semester and occupies the first third of the typical textbook. This necessary prelude to the main event is comparable in scope to precalculus though not broken out as a formal ‘prechemistry’ course. Atomic orbitals account for much of this prelude-to-chemistry. By tradition, orbital theory is conveyed to the student in three disjunct pieces, presented in the following illogical order: the Pauli principle, the Aufbau principle, (...)
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  16.  81
    Mereology and quantum chemistry: the approximation of molecular orbital[REVIEW]Jean-Pierre Llored - 2010 - Foundations of Chemistry 12 (3):203-221.
    Mulliken proposed an Aufbauprinzip for the molecules on the basis of molecular spectroscopy while establishing, point by point, his concept of molecular orbit. It is the concept of electronic state which becomes the lever for his attribution of electronic configurations to a molecule. In 1932, the concept of orbit was transmuted into that of the molecular orbital to integrate the probabilistic approach of Born and to achieve quantitative accuracy. On the basis of the quantum works of Hund, Wigner, Lennard-Jones (...)
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  17.  46
    The Averaged Dynamics of the Hydrogen Atom in Crossed Electric and Magnetic Fields as a Perturbed Kepler Problem.Nils Berglund & Turgay Uzer - 2001 - Foundations of Physics 31 (2):283-326.
    We treat the classical dynamics of the hydrogen atom in perpendicular electric and magnetic fields as a celestial mechanics problem. By expressing the Hamiltonian in appropriate action–angle variables, we separate the different time scales of the motion. The method of averaging then allows us to reduce the system to two degrees of freedom, and to classify the most important periodic orbits.
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  18.  32
    The Effect of the Relative Motion of Atoms on the Frequency of the Emitted Light and the Reinterpretation of the Ives-Stilwell Experiment.C. I. Christov - 2010 - Foundations of Physics 40 (6):575-584.
    We examine the process of the emission of light from an atom that is in a relative translational motion with respect to the medium at rest in which the electromagnetic excitations propagate. The effect of Lorentz contraction of the of electron orbits on the emitted frequency is incorporated in the Rydberg formula, as well as the emitter’s Doppler effect is acknowledged. The result is that the frequency of the emitted light is modified by a factor that is identical with what (...)
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  19.  5
    Electron Wave Trajectories Within Schrodinger’s Hydrogen Atom, and Relativistic Consequences.Leslie Smith - 2023 - Foundations of Physics 53 (5):1-14.
    Quantum mechanics teaches that before detection, knowledge of particle position is, at best, probabilistic, and classical trajectories are seen as a feature of the macroscopic world. These comments refer to detected particles, but we are still free to consider the motions generated by the wave equation. Within hydrogen, the Schrodinger equation allows calculation of kinetic energy at any location, and if this is identified as the energy of the wave, then radial momentum, allowing for spherical harmonics, becomes available. The distance (...)
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  20. A New method for Analysis of Biomolecules Using the BSM-SG Atomic Models.Stoyan Sarg Sargoytchev - 2017 - J. Biom Biostat 8 (2):1000339.
    Biomolecules and particularly proteins and DNA exhibit some mysterious features that cannot find satisfactory explanation by quantum mechanical modes of atoms. One of them, known as a Levinthal’s paradox, is the ability to preserve their complex three-dimensional structure in appropriate environments. Another one is that they possess some unknown energy mechanism. The Basic Structures of Matter Supergravitation Unified Theory (BSM-SG) allows uncovering the real physical structures of the elementary particles and their spatial arrangement in atomic nuclei. The resulting physical (...)
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  21.  42
    The 4s and 3d subshells: Which one fills first in progressing through the periodic table and which one fills first in any particular atom? [REVIEW]Sadegh Salehzadeh & Farahnaz Maleki - 2016 - Foundations of Chemistry 18 (1):57-65.
    In this paper, first we discuss an old problem in teaching electron configuration of transition metals and the order in which the orbitals are filled. Then we propose two simple computational experiments, in order to show that in the case of first row transition metals and the main group elements after them, the electrons occupy the 3d subshell before the 4s. It is shown that if we begin with the bare nucleus of above elements in the vacuum and then continue (...)
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  22.  44
    Acerca del status ontológico de las entidades químicas: el caso de los orbitales atómicos.Martín Labarca & Olimpia Lombardi - 2010 - Principia: An International Journal of Epistemology 14 (3):309-333.
    The aim of the present paper is to analyze the problem of the relationship between chemistry and physics, by focusing on the widely discussed case of the atomic orbitals. We will begin by remembering the difference between the physical and the chemical interpretation of the concept of orbital. Then, we will refer to the claim made in 1999 that atomic orbitals have been directly imaged for the first time. On this basis, we will analyze the problem from (...)
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  23.  19
    1. Preliminaries.on Atomic Join-Semilattices - 1989 - Bulletin of the Section of Logic 18 (3):105-111.
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  24. Hibbert~ journal.Iii Atomic Energy & Lp Jacks - 1946 - Hibbert Journal: A Quarterly Review of Religion, Theology, and Philosophy 44:1.
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  25.  61
    Ethics of HIV cure research: an unfinished agenda. [REVIEW]Jeremy Sugarman, John A. Sauceda, Brandon Brown, Parya Saberi, Mallory O. Johnson, Laney Henley, Samuel Ndukwe, Hursch Patel, Morénike Giwa Onaiwu, Danielle M. Campbell, David Palm, Orbit Clanton, David Kelly, Jan Kosmyna, Michael Louella, Laurie Sylla, Christopher Roebuck, Nora Jones, Lynda Dee, Jeff Taylor, John Kanazawa & Karine Dubé - 2021 - BMC Medical Ethics 22 (1):1-14.
    BackgroundThe pursuit of a cure for HIV is a high priority for researchers, funding agencies, governments and people living with HIV (PLWH). To date, over 250 biomedical studies worldwide are or have been related to discovering a safe, effective, and scalable HIV cure, most of which are early translational research and experimental medicine. As HIV cure research increases, it is critical to identify and address the ethical challenges posed by this research.MethodsWe conducted a scoping review of the growing HIV cure (...)
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  26.  22
    Wave-mechanical model for chemistry.Jan C. A. Boeyens - 2015 - Foundations of Chemistry 17 (3):247-262.
    The strength and defects of wave mechanics as a theory of chemistry are critically examined. Without the secondary assumption of wave–particle duality, the seminal equation describes matter waves and leaves the concept of point particles undefined. To bring the formalism into line with the theory of special relativity, it is shown to require reformulation in hypercomplex algebra that imparts a new meaning to electron spin as a holistic spinor, eliminating serious current misconceptions in the process. Reformulation in the curved space–time (...)
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  27. Czy można zaobserwować orbitale? O problemie obserwowalności i realności przedmiotów teoretycznych.Paweł Zeidler - 2010 - Filozofia Nauki 18 (4).
    In September 1999 "Nature" magazine announced that atomic orbitals were di-rectly observed. Opposing it, Eric Scerri, editor-in-chief of "Foundations of Chemistry", claimed that what could be observed in the experiment was electron density, not orbitals. The main purpose of this paper is to consider philosophical and methodological aspects of the above controversy. Especially, the problems of direct observability and reality of theoretical entities are taken under detailed discussion. From the point of view of quantum mechanics there are not any (...)
     
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  28. Recommended questions on the road towards a scientific explanation of the periodic system of chemical elements with the help of the concepts of quantum physics.W. H. Eugen Schwarz - 2006 - Foundations of Chemistry 9 (2):139-188.
    Periodic tables (PTs) are the ‘ultimate paper tools’ of general and inorganic chemistry. There are three fields of open questions concerning the relation between PTs and physics: (i) the relation between the chemical facts and the concept of a periodic system (PS) of chemical elements (CEs) as represented by PTs; (ii) the internal structure of the PS; (iii)␣The relation between the PS and atomistic quantum chemistry. The main open questions refer to (i). The fuzziness of the concepts of chemical properties (...)
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  29.  42
    Response to Vollmer’s Review of Minds and Molecules.Eric Scerri - 2003 - Philosophy of Science 70 (2):391-398.
    I present a response to Vollmer's review of the book Of Minds and Molecules, and especially her comments on my own article therein. This provides an opportunity to discuss two central ideas in the philosophy of chemistry. These are the distinction between elements as simple substances (element-1) and elements as basic substances (element-2) and Paneth's proposed intermediate position for philosophy of chemistry. The response also discusses the question of isotopes in relationship to the nature of the elements and their classification (...)
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  30.  8
    Why do prima facie intuitive theories work in organic chemistry?Hirofumi Ochiai - 2023 - Foundations of Chemistry 25 (3):359-367.
    In modern German ‘Anschauung’ is translated as intuition. But in Kant’s technical philosophical context, it means an intuition derived from previous visualizations of physical processes in the world of perceptions. The nineteenth century chemists’ predilection for Kantian Anschauung led them to develop an intuitive representation of what exists beyond the bounds of the senses. Molecular structure is one of the illuminating outcomes. (Ochiai 2021, pp. 1–51) This mental habit seems to be dominant among chemists even in the twentieth century, as (...)
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  31.  76
    Entropic concepts in electronic structure theory.Roman F. Nalewajski - 2012 - Foundations of Chemistry 16 (1):27-62.
    It is argued that some elusive “entropic” characteristics of chemical bonds, e.g., bond multiplicities (orders), which connect the bonded atoms in molecules, can be probed using quantities and techniques of Information Theory (IT). This complementary perspective increases our insight and understanding of the molecular electronic structure. The specific IT tools for detecting effects of chemical bonds and predicting their entropic multiplicities in molecules are summarized. Alternative information densities, including measures of the local entropy deficiency or its displacement relative to the (...)
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  32.  6
    Acerca del status ontológico de las entidades químicas: el caso de los orbitales atómicos DOI:10.5007/1808-1711.2010v14n3p309. [REVIEW]Martín Labarca & Olimpia Lombardi - 2010 - Principia: An International Journal of Epistemology 14 (3):309-333.
    The aim of the present paper is to analyze the problem of the relationship between chemistry and physics, by focusing on the widely discussed case of the atomic orbitals. We will begin by remembering the difference between the physical and the chemical interpretation of the concept of orbital. Then, we will refer to the claim made in 1999 that atomic orbitals have been directly imaged for the first time. On this basis, we will analyze the problem from (...)
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  33. Mereologies as the grammars of chemical discourses.Rom Harré & Jean-Pierre Llored - 2011 - Foundations of Chemistry 13 (1):63-76.
    Mereology is the logic of part—whole concepts as they are used in many different contexts. The old chemical metaphysics of atoms and molecules seems to fit classical mereology very well. However, when functional attributes are added to part specifications and quantum mechanical considerations are also added, the rules of classical mereology are breached in chemical discourses. A set theoretical alternative mereology is also found wanting. Molecular orbital theory requires a metaphysics of affordances that also stands outside classical mereology.
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  34.  48
    The use of one-electron quantum numbers to describe polyelectronic systems.Robert M. Richman - 1999 - Foundations of Chemistry 1 (2):173-181.
    Atomic states are rigorously characterized by the total orbital angular momentum and the total spin angular momentum, but chemists persist in the use of electron configurations based on one-electron quantum numbers and simplified rules for predicting ground state configurations. This practice is defended against two lines of criticism, and its use in teaching chemistry is encouraged with the claim that the inductive approach of Mendeleev and the deductive approach initiated by Schrödinger compose the consummate example of that interaction (...)
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  35.  72
    Variations on the Kepler problem.Johndale C. Solem - 1997 - Foundations of Physics 27 (9):1291-1306.
    The elliptical orbits resulting from Newtonian gravitation are generated with a multifaceted symmetry, mainly resulting from their conservation of both angular momentum and a vector fixing their orientation in space—the Laplace or Runge-Lenz vector. From the ancient formalisms of celestial mechanics, I show a rather counterintuitive behavior of the classical hydrogen atom, whose orbits respond in a direction perpendicular to a weak externally-applied electric field. I then show how the same results can be obtained more easily and directly from the (...)
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  36. Dynamic and stochastic systems as a framework for metaphysics and the philosophy of science.Christian List & Marcus Pivato - 2021 - Synthese 198 (3):2551-2612.
    Scientists often think of the world as a dynamical system, a stochastic process, or a generalization of such a system. Prominent examples of systems are the system of planets orbiting the sun or any other classical mechanical system, a hydrogen atom or any other quantum–mechanical system, and the earth’s atmosphere or any other statistical mechanical system. We introduce a general and unified framework for describing such systems and show how it can be used to examine some familiar philosophical questions, including (...)
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  37.  97
    The Practical Kinds Model as a Pragmatist Theory of Classification.Peter Zachar - 2002 - Philosophy, Psychiatry, and Psychology 9 (3):219-227.
    In lieu of an abstract, here is a brief excerpt of the content:Philosophy, Psychiatry, & Psychology 9.3 (2002) 219-227 [Access article in PDF] The Practical Kinds Model as a Pragmatist Theory of Classification Peter Zachar Pragmatist theories of scientific classification are intended to be pluralistic models that recognize different ways of cutting up the world as valuable, but do not require us to adopt whatever-goes relativism or metaphysical antirealism. How ironic that my application of pragmatism to psychopathology has been charged (...)
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  38.  4
    Chemistry beyond the ‘positivism vs realism' debate.Bernadette Bensaude-Vincent - unknown
    It is often assumed that chemistry was a typical positivistic science as long as chemists used atomic and molecular models as mere fictions and denied any concern with their real existence. Even when they use notions such as molecular orbitals chemists do not reify them and often claim that they are mere models or instrumental artefacts. However a glimpse on the history of chemistry in the longue durée suggests that such denials of the ontological status of chemical entities do (...)
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  39.  47
    Chemistry, an ontology-free science?Bernadette Bensaude-Vincent - unknown
    It is often assumed that chemistry was a typical positivistic science as long as chemists used atomic and molecular models as mere fictions and denied any concern with their real existence. Even when they use notions such as molecular orbitals chemists do not reify them and often claim that they are mere models or instrumental artefacts. However a glimpse on the history of chemistry in the longue durée suggests that such denials of the ontological status of chemical entities do (...)
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  40.  9
    Neo-classical Relativistic Mechanics Theory for Electrons that Exhibits Spin, Zitterbewegung, Dipole Moments, Wavefunctions and Dirac’s Wave Equation.James L. Beck - 2023 - Foundations of Physics 53 (3):1-39.
    In this work, a neo-classical relativistic mechanics theory is presented where the spin of an electron is an inherent part of its world space-time path as a point particle. The fourth-order equation of motion corresponds to the same covariant Lagrangian function in proper time as in special relativity except for an additional spin energy term. The theory provides a hidden-variable model of the electron where the dynamic variables give a complete description of its motion, giving a classical mechanics explanation of (...)
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  41.  8
    The semiotic abstraction.Russell Daylight - 2017 - Semiotica 2017 (218):81-90.
    When we press the “A” key on our computer keyboard, an “a” appears on our screen almost simultaneously. In between those two points there are a number of layers of computer program which communicate with each other: the keyboard controller sends a message to the operating system which is interpreted by a word processor, which then returns a message to the operating system, which communicates with the video controller and the video board sends a message that it needs an “a” (...)
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  42.  2
    Deciphering the physical meaning of Gibbs’s maximum work equation.Robert T. Hanlon - forthcoming - Foundations of Chemistry:1-11.
    J. Willard Gibbs derived the following equation to quantify the maximum work possible for a chemical reaction$${\text{Maximum work }} = \, - \Delta {\text{G}}_{{{\text{rxn}}}} = \, - \left( {\Delta {\text{H}}_{{{\text{rxn}}}} {-}{\text{ T}}\Delta {\text{S}}_{{{\text{rxn}}}} } \right) {\text{ constant T}},{\text{P}}$$ Maximum work = - Δ G rxn = - Δ H rxn - T Δ S rxn constant T, P ∆Hrxn is the enthalpy change of reaction as measured in a reaction calorimeter and ∆Grxn the change in Gibbs energy as measured, if (...)
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  43. 'The handmaiden of industry': Marine science and fisheries development in south Africa 1895-1939.C. Revelle, S. Snyder, P. Nagels, E. Sleeckx, R. Callaerts, L. Tichy & L. Sittert - 1995 - Studies in History and Philosophy of Science Part A 26 (4):531-558.
    The preparation of layers of amorphous Se by plasma-enhanced CVD using the hydride H2Se as precursor gas is described. Information concerning the structure of the films was obtained from Raman spectroscopy. The spectra of amorphous Se indicated that the dominant molecular structure is the eight-membered ring and/or a chain with Se8 molecular fragments. This material exhibited reversible photodarkening when illuminated at 77 K. In order to explain this phenomenon, we propose a mechanism which takes into account the role of the (...)
     
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  44. The Contexts of Simultaneous Discovery: Slater, Pauling, and the Origins of Hybridisation.B. S. Park - 2000 - Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics 31 (4):451-474.
    This paper investigates a well-known case of simultaneous discovery in twentieth-century chemistry, the origins of the concept of hybridisation, in the light of Kuhn's insights. There has been no ambiguity as to who discovered this concept, when it was "rst in print, and how important it was. The full-#edged form of the concept was published in 1931 independently by two American scientists John C. Slater (1900}1976) and Linus Pauling (1901}1994), although both of them had made their ideas public earlier: Slater (...)
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  45. Meillassoux’s Virtual Future.Graham Harman - 2011 - Continent 1 (2):78-91.
    continent. 1.2 (2011): 78-91. This article consists of three parts. First, I will review the major themes of Quentin Meillassoux’s After Finitude . Since some of my readers will have read this book and others not, I will try to strike a balance between clear summary and fresh critique. Second, I discuss an unpublished book by Meillassoux unfamiliar to all readers of this article, except those scant few that may have gone digging in the microfilm archives of the École normale (...)
     
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  46.  63
    Crafting the quantum: Arnold Sommerfeld and the older quantum theory.Suman Seth - 2008 - Studies in History and Philosophy of Science Part A 39 (3):335-348.
    Arnold Sommerfeld was among the most important students of the so-called ‘older’ quantum theory. His many contributions included papers in 1915 and 1916 extending Niels Bohr’s ‘planetary’ model of the atom beyond circular orbits and his incorporation of relativistic corrections in order to explain hydrogenic fine structure. Originally a realist in his use of Bohr’s model, Sommerfeld became increasingly disillusioned with model-building in general in the late nineteen-teens and early nineteen-twenties. This paper explores Sommerfeld’s use of the term Zahlenmysterium as (...)
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  47. THIS IS NICE OF YOU. Introduction by Ben Segal.Gary Lutz - 2011 - Continent 1 (1):43-51.
    Reproduced with the kind permission of the author. Currently available in the collection I Looked Alive . © 2010 The Brooklyn Rail/Black Square Editions | ISBN 978-1934029-07-7 Originally published 2003 Four Walls Eight Windows. continent. 1.1 (2011): 43-51. Introduction Ben Segal What interests me is instigated language, language dishabituated from its ordinary doings, language startled by itself. I don't know where that sort of interest locates me, or leaves me, but a lot of the books I see in the stores (...)
     
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  48.  40
    Spin-Dependent Bohmian Electronic Trajectories for Helium.J. A. Timko & E. R. Vrscay - 2009 - Foundations of Physics 39 (9):1055-1071.
    We examine “de Broglie-Bohm” causal trajectories for the two electrons in a nonrelativistic helium atom, taking into account the spin-dependent momentum terms that arise from the Pauli current. Given that this many-body problem is not exactly solvable, we examine approximations to various helium eigenstates provided by a low-dimensional basis comprised of tensor products of one-particle hydrogenic eigenstates.First to be considered are the simplest approximations to the ground and first-excited electronic states found in every introductory quantum mechanics textbook. For example, the (...)
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  49.  46
    Heisenberg's observability principle.Johanna Wolff - 2014 - Studies in History and Philosophy of Science Part B: Studies in History and Philosophy of Modern Physics 45:19-26.
    Werner Heisenberg's 1925 paper ‘Quantum-theoretical re-interpretation of kinematic and mechanical relations’ marks the beginning of quantum mechanics. Heisenberg famously claims that the paper is based on the idea that the new quantum mechanics should be ‘founded exclusively upon relationships between quantities which in principle are observable’. My paper is an attempt to understand this observability principle, and to see whether its employment is philosophically defensible. Against interpretations of ‘observability’ along empiricist or positivist lines I argue that such readings are philosophically (...)
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  50. Qu'est-ce que le realisme scientifique?Howard Sankey - 2002 - Reseaux 94:69-82.
    Les tables, les chaises, les gens assis sur des chaises, à des tables sont des objets composés de matière. Selon la science, la matière se compose principalement d'atomes. Les atomes sont faits d'électrons, de neutrons et de protons. Les neutrons et les protons forment un noyau autour duquel orbitent les électrons. Outre ces particules, les physiciens en ont découvert un grand nombre d'autres, comme les photons, les quarks et les neutrinos.
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