ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Collective fluctuations of conserved variables in liquids (1993)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 98 (1993), S. 3224-3239 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Prominent among the classes of collective excitations in liquids that one would like to study are those which are compelled to obey some sort of conservation law. The instantaneous normal modes of liquid (which must be translationally invariant or, equivalently, conserve momentum) comprise one such example. The set of relaxation pathways dictated by a master-equation description of energy transfer in a liquid—which must conserve probability—constitutes another. We show that these conservation laws do impose fairly stringent requirements on the nature of the collective behavior, but the resulting excitations can nonetheless be described by liquid-theory methods. Within linear liquid theories, the desired distribution of modes ends up being a combination of a delocalized electronic-band-like portion and a fluctuating local field contribution. We illustrate the results with an explicit calculation (at the master-equation level) of energy-transfer kinetics in a liquid.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.464095
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Liquid theory for the instantaneous normal modes of a liquid (1994)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 100 (1994), S. 5123-5138 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: At short enough times, the dynamics of a liquid can be resolved rigorously into independent simple harmonic motions called instantaneous normal modes. The spectrum of such modes is easily accessible via computer simulation, but, despite the existence of theories for other kinds of liquid modes, it has been difficult to come up with analytical approaches of power sufficient to explain the universal appearance of instantaneous normal-mode spectra—though Wu and Loring were recently able to arrive at a theory by exploiting the analogy between this problem and the master equation. In this paper we propose a hierarchy of liquid-theoretical treatments that do show the analogy between instantaneous normal modes and other collective excitations in liquids, but are nonetheless capable of leading to accurate predictions of instantaneous normal-mode spectra. The crucial ideas are that the theoretical treatment must respect the fact these modes conserve momentum and must also recognize the strongly local character of intermolecular force constants. We discuss two theories in detail—a renormalized mean-field theory, which turns out to be identical to the Wu–Loring theory, and a higher-order theory—and apply both to a simple atomic liquid. Both theories successfully predict the results of computer simulations, including the fact that the spectrum depends much more on density than on temperature in the normal liquid range. The higher-order theory, though, gives a slightly more accurate prediction of the fraction of imaginary modes.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.467178
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Superconductivity in a two-dimensional electron gas (1998)
    [s.l.] : Macmillan Magazines Ltd.
    Nature 395 (1998), S. 253-257 
    Details
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] In a series of recent experiments, Kravchenko and colleagues, observed unexpectedly that a two-dimensional electron gas in zero magnetic field can become conducting at low temperatures: the two-dimensionality was imposed by confining the electron gas to the interface between two semiconductors. ...
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/26179
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Prediction of Multiple Frequencies Chatter Stability in High-Speed Milling System (2008)
    s.l. ; Stafa-Zurich, Switzerland
    Key engineering materials Vol. 375-376 (Mar. 2008), p. 564-568 
    Details
    ISSN: 1013-9826
    Source: Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: A new dynamics model for multi-degree of freedom high-speed milling system isproposed, which takes account of regenerative effects and the effects of the relative vibration ofspindle axis in milling process. Based on the mode synthesis theory and the zeroth-orderapproximation of the Fourier series, an integrated stability analytical method for multiple frequenciesis presented, which involves multiple orders modal characteristics and higher order excitations inhigh-speed milling process. The chatter stability lobes are predicted in the frequency domain using theproposed stability analytical method, and verified by milling experiments. It is shown that stabilityregions involving multiple natural modes are reduced contrary to the case of single natural mode
    Type of Medium: Electronic Resource
    URL: http://www.tib-hannover.de/fulltexts/2011/0528/01/57/transtech_doi~10.4028%252Fwww.scientific.net%252FKEM.375-376.564.pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    The Assessment of Cutting Temperature Measurements in High-Speed Machining (2004)
    s.l. ; Stafa-Zurich, Switzerland
    Materials science forum Vol. 471-472 (Dec. 2004), p. 162-166 
    Details
    ISSN: 1662-9752
    Source: Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: High-speed machining has received important interest because it leads to an increase of productivity and a better workpiece surface quality. However, the tool wear increases dramatically in high-speed machining (HSM) operations due to the high cutting temperature at the tool-workpiece interface and chip-tool interface. Cutting temperature and its gradient play an important role in tool life and machined part accuracy. This paper reviews different methods of the measurements of cutting temperature, which include: (1) thermocouples---tool-work thermocouple, embedded thermocouple, combination thermocouple and compensation thermocouple (2) optical infrared pyrometer, (3) infra-red photography, (4) thermal paints, (5) microstructure or microhardness observation. Each method has its advantages and limitations. The fundamental principles and application fields of each measurement method are presented, which is useful for the selection of the measurement methods for high-speed cutting temperature
    Type of Medium: Electronic Resource
    URL: http://www.tib-hannover.de/fulltexts/2011/0528/02/09/transtech_doi~10.4028%252Fwww.scientific.net%252FMSF.471-472.162.pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Recent Developments in Tool Materials for High Speed Machining (2004)
    s.l. ; Stafa-Zurich, Switzerland
    Materials science forum Vol. 471-472 (Dec. 2004), p. 438-442 
    Details
    ISSN: 1662-9752
    Source: Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: High-Speed Machining (HSM) is one of the emerging cutting processes, which ismachining at a speed significantly higher than the speed commonly in use on the shop floor. In the last twenty years, high speed machining has received an important attention as a technological solution for high productivity to increase economic efficiency in manufacturing. The recent developments in cutting tool materials for high speed machining are reviewed in this paper. The appropriate applications of the high speed machining technology are presented. The research is great beneficial tothe design and the optimal selection of tool materials for high speed machining
    Type of Medium: Electronic Resource
    URL: http://www.tib-hannover.de/fulltexts/2011/0528/02/09/transtech_doi~10.4028%252Fwww.scientific.net%252FMSF.471-472.438.pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    The Impact of Tool Materials and Cutting Parameters on Surface Roughness in High-Speed Face-Milling (2004)
    s.l. ; Stafa-Zurich, Switzerland
    Key engineering materials Vol. 259-260 (Mar. 2004), p. 462-465 
    Details
    ISSN: 1013-9826
    Source: Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    URL: http://www.tib-hannover.de/fulltexts/2011/0528/01/47/transtech_doi~10.4028%252Fwww.scientific.net%252FKEM.259-260.462.pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Development of Case-Based Database for High-Speed Machining (2004)
    s.l. ; Stafa-Zurich, Switzerland
    Key engineering materials Vol. 259-260 (Mar. 2004), p. 829-833 
    Details
    ISSN: 1013-9826
    Source: Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Type of Medium: Electronic Resource
    URL: http://www.tib-hannover.de/fulltexts/2011/0528/01/47/transtech_doi~10.4028%252Fwww.scientific.net%252FKEM.259-260.829.pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Study on Interface Reaction and Its Control of Titanium Fiber-Hydroxyapatite Composites (2007)
    s.l. ; Stafa-Zurich, Switzerland
    Key engineering materials Vol. 330-332 (Feb. 2007), p. 507-510 
    Details
    ISSN: 1013-9826
    Source: Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Various reinforcements have been used to reinforce hydroxyapatite composites.Bioactivity of hydroxyapatite and excellent mechanical properties of titanium make titanium fiberreinforced hydroxyapatite composite a promising biomaterial. In this work, a titanium fiber waschosen as the reinforcement, and hydroxyapatite powders prepared by wet precipitation methodwere used as matrix material. The interface between titanium fiber and hydroxyapatite wasinvestigated in terms of microstructure and chemical composition using a combination of scanningelectron microscopy (SEM), X-ray diffraction (XRD) and energy disperse spectroscopy (EDS).Experimental results showed that titanium/hydroxyapatite composite with controllable interfacecould be made by choosing proper preparation method
    Type of Medium: Electronic Resource
    URL: http://www.tib-hannover.de/fulltexts/2011/0528/01/52/transtech_doi~10.4028%252Fwww.scientific.net%252FKEM.330-332.507.pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Constitutive Equation for 7050 Aluminum Alloy at High Temperatures (2006)
    s.l. ; Stafa-Zurich, Switzerland
    Materials science forum Vol. 532-533 (Dec. 2006), p. 125-128 
    Details
    ISSN: 1662-9752
    Source: Scientific.Net: Materials Science & Technology / Trans Tech Publications Archiv 1984-2008
    Topics: Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
    Notes: Accurately material constitutive model is essential to understand and predict machiningprocess. High temperature split Hopkinson pressure bar (SHPB) test system is used to investigateflow stress behavior and characteristics of 7050-T7451 aluminum alloy. Specimens are tested from200℃ to 550℃ at intervals of 50℃ and room temperature, at strain-rate of 2800s-1. The experimentalresults show that flow stress is strongly dependent on temperature as well as strain rate, flow stressdecreases with the increase of temperature, while increase with the increasing of strain rate. Thematerial parameters are determined for both Johnson-Cook constitutive equation and modifiedJohnson-Cook constitutive equation. The modified JC equation is more suitable for expressing thedynamic behavior of 7050-T7451 aluminum alloy
    Type of Medium: Electronic Resource
    URL: http://www.tib-hannover.de/fulltexts/2011/0528/02/14/transtech_doi~10.4028%252Fwww.scientific.net%252FMSF.532-533.125.pdf
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...