Author: James Victor WoodrickPublisher:
ISBN:
Category : Molecular beams
Languages : en
Pages : 98
Book Description
Development of a high intensity molecular beam by expansion of a mixed gas through a supersonic nozzle
Author: James Victor WoodrickPublisher:
ISBN:
Category : Molecular beams
Languages : en
Pages : 98
Book Description
Development of a Shock-tube Driven Molecular Beam
Author: George T. SkinnerPublisher:
ISBN:
Category : Detectors
Languages : en
Pages : 78
Book Description
The preliminary development of a high intensity molecular beam, in which a small tailored interface hypersonic shock-tunnel is used as the gas source, is reported. The aim is to extend molecular beam techniques into the 1-10 e.v. per particle range by utilizing the capability of the shock tube to generate high temperatures. A 0.7 e.v. nitrogen beam was produced in the pilot apparatus. The intensity of 2.5 x 10 to the 18th power molecules 1/sq.cm./sec. and the spreading angle of 6 deg agree with a theoretical analysis which takes into account attenuation caused by scattered molecules which have been thermally accommodated at the walls of the apparatus. A modified Kantrowitz-Grey system is used to obtain the high-energy beam.
Supersonic Nozzle Beams - Some Recent Experimental Results
Author: J. B. AndersonPublisher:
ISBN:
Category :
Languages : en
Pages : 28
Book Description
The application of molecular beam techniques to a study of the collision processes important in gas dynamics and aerothermochemistry is described. Emphasis is placed on the characteristics of molecular beams formed by a nozzle source. It is shown that the available intensities from nozzle beams are substantially larger than those from classical effusive sources, the spread in molecular velocities in nozzle beams is much more narrow than the corresponding spread in effusion beams, and the nozzle beam energy is larger than that of the effusion beam at the same source temperature. Experimental results are presented which show that nozzle beam energies in excess of 1 ev/particle can be produced by aerodynamic acceleration of heavy molecules in a light gas with the binary gas mixture in the nozzle source near room temperature. The effects of binary mixture mass ratio, source temperature, and specific heat ratio on the attainable beam energy are shown to be adequately described by a simple theory based on the isentropic expansion of a pure gas having a molecular weight corresponding to the concentration-weighted mean for the mixture. The use of nozzle beams as probes and the use of beam velocity analysis are shown to represent a powerful method for the study of relaxation rates of various kinds; e.g., in the exhaust nozzles of various propulsion systems. (Author).
Introduction to Molecular Beams Gas Dynamics
Author: Giovanni SannaPublisher: Imperial College Press
ISBN: 1860947409
Category : Science
Languages : en
Pages : 404
Book Description
Introduction to Molecular Beams Gas Dynamics is devoted to the theory and phenomenology of supersonic molecular beams. The book describes the main physical idea and mathematical methods of the gas dynamics of molecular beams, while the detailed derivation of results and equations is accompanied by an explanation of their physical meaning. Many of the applications of supersonic molecular beams are discussed, including their application to molecular spectroscopy, and the study of surface phonons by monoatomic and monokinetic beams, and the study of intermolecular potentials and the onset of condensation. The phenomenology of supersonic beams can appear complex to those not experienced in supersonic gas dynamics and, as a result, the few existing reviews on the topic generally assume a limited level of knowledge. The book begins with a quantitative description of the fundamental laws of gas dynamics and goes on to explain such phenomena. It analyzes the evolution of the gas jet from the continuum to the regime of almost free collisions between molecules, and includes numerous figures, illustrations, tables and references.
Masters Theses and Doctoral Dissertations in the Pure and Applied Sciences Accepted by Colleges and Universities of the United States
Author: Air Force Research Resumés
Author: Atomic and Molecular Beams
Author: Roger CamparguePublisher: Springer Science & Business Media
ISBN: 3642568009
Category : Science
Languages : en
Pages : 1013
Book Description
This title covers the state of the art in this field both theoretically and experimentally. With contributions from leading researchers including several Nobel laureates, it represents a long-lasting source of reference on all aspects of fundamental research into or using atomic and molecular beams.
Scientific and Technical Aerospace Reports
Author: Intermolecular Forces
Author: Pierre L. HuyskensPublisher: Springer Science & Business Media
ISBN: 3642762603
Category : Science
Languages : en
Pages : 490
Book Description
The study of intermolecular forces began over one hundred years ago in 1873 with the famous thesis of van der Waals. In recent decades, knowledge of this field has expanded due to intensive research into both its theoretical and the experimental aspects. This is particularly true for the type of very strong cohesive force stressed in 1920 by Latimer and Rodebush: the hydrogen bond, a phenomenon already outlined in 1912 by Moore and Winemill. Hydrogen bonds exert a profound influence on most of the physical and chemical properties of the materials in which they are formed. Not only do they govern viscosity and electrical conductivity, they also intervene in the chemical reaction path which determines the kinetics of chemical processes. The properties of chemical substances depend to a large extent on intermolecular forces. In spite of this fundamental fact, too little attention is given to these properties both in research and in university teaching. For instance, in the field of pharmaceutical research, about 13000 compounds need to be studied in order to find a single new product that can be successfully marketed. The recognition of the need to optimize industrial research efficiency has led to a growing interest in promoting the study of inter molecular forces. Rising salary costs in industry have encou raged an interest in theoretical ideas which will lead to tailor made materials.
Nanostructured Carbon for Advanced Applications
Author: Giorgio BenedekPublisher: Springer Science & Business Media
ISBN: 9401008582
Category : Science
Languages : en
Pages : 366
Book Description
Proceedings of the NATO Advanced Study Institute, Erice, Sicily, Italy, July 19-31, 2000