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  • 1
    Electronic Resource
    Electronic Resource
    The electronic structure of a liquid of interacting hydrogenic atoms: A prototype for expanded liquid metals (1988)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 89 (1988), S. 7388-7400 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The electronic structure of a metal heated above its critical temperature (an "expanded liquid metal'') shows dramatic changes as the density is increased. There is some experimental evidence that as one proceeds from insulating to metallic behavior the substance can even go through two separate phase transitions: from an ordinary insulator to a so-called excitonic insulator, and then from an excitonic insulator to a metal. In an effort to study how the metallic phase is approached, we have used discretized-path-integral methods to look at the statistical mechanics and the electronic structure of a model liquid. In the gas phase, the atoms in the model have a single valence electron constrained to occupy one of the s or p orbitals of the valence shell, but at higher densities, the orbitals hybridize, leading to instantaneous dipole–dipole interaction. We show that formulating this electronic structure in terms of occupation numbers allows us to monitor the hybridization evolution via an imaginary-time correlation function—which we calculate from an analytical solution to the mean-spherical approximation for the model. The numerical results strongly suggest that the model has a sudden hybridization transition, suggesting, in turn, that it might be profitable to think of the excitonic insulator transition in this language.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.455270
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  • 2
    Electronic Resource
    Electronic Resource
    Liquid theory for band structure in a liquid. II. p orbitals and phonons (1990)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 92 (1990), S. 1923-1935 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: Surprisingly, the ground-state quantum mechanical problem of calculating the set of single-electron states available to a liquid (its electronic band structure) can be turned into an exercise in ordinary classical liquid theory. We generalize our previous findings by showing that this statement continues to hold for bands constructed from a basis of atomic p orbitals and we use this idea to provide a simple mean field theory useful for p bands in liquids. In addition, there is a natural way of thinking about the normal modes of vibration of a liquid (its phonons) that is accessible through virtually the same formalism. We discuss the significance of these "instantaneous normal modes'' and show that the same kind of mean field theory is helpful in understanding both this phonon spectrum and its implications for liquid-state dynamics.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.458023
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  • 3
    Electronic Resource
    Electronic Resource
    Liquid theory for band structure in a liquid (1989)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 91 (1989), S. 5613-5627 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: When electron correlation effects are small, the set of energy levels available to both the localized and the delocalized individual electrons (the band structure) is the starting place for determining the macroscopic electronic properties of a substance. Calculating the band structure in any disordered medium, however, requires facing the problem that there will always be a distribution of geometries in the material—at least the local parts of which must be accounted for in order to get any reasonable results. In a liquid this requirement means that the liquid structure plays an important role. We show in this paper that the band structure in a liquid is completely and rigorously determined by the equilibrium behavior of an "effective'' liquid with artificial internal degrees of freedom. This mapping implies that standard liquid theory methods (which automatically build in the correct liquid structure) can be used to find the electronic energy levels. As illustration, we use the mean-spherical approximation (MSA) to derive a simple expression for the density of states that is accurate at all but the lowest densities. We further show that this particular MSA theory is identical to an apparently different theory derived recently by Logan and Winn—which makes both theories identical to the so–called EMA theory of Roth. An even more general correspondence exists between our exact formalism and the exact formalism of Logan and Winn, though any given approximation might be more natural in one approach then in another.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.457564
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  • 4
    Electronic Resource
    Electronic Resource
    Dielectric screening of Coulomb interactions in polymers (1992)
    s.l. : American Chemical Society
    Macromolecules 25 (1992), S. 1694-1698 
    Details
    ISSN: 1520-5835
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/ma00032a011
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  • 5
    Electronic Resource
    Electronic Resource
    Host-Guest Mesomorphism: Cooperative Stabilization of a Bowlic Columnar Phase (1995)
    s.l. : American Chemical Society
    Journal of the American Chemical Society 117 (1995), S. 5011-5012 
    Details
    ISSN: 1520-5126
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/ja00122a039
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  • 6
    Electronic Resource
    Electronic Resource
    Rigid bowlic liquid crystals based on tungsten-oxo calix[4]arenes: host-guest effects and head-to-tail organization (1993)
    s.l. : American Chemical Society
    Journal of the American Chemical Society 115 (1993), S. 1159-1160 
    Details
    ISSN: 1520-5126
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/ja00056a056
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  • 7
    Electronic Resource
    Electronic Resource
    Synthesis and characterization of ferrocene-containing new schiff base complexes. The X-ray crystal structure of (C"1"0H"6N"2)CNNCHFc
    Amsterdam : Elsevier
    Polyhedron 11 (1992), S. 1917-1922 
    Details
    ISSN: 0277-5387
    Source: Elsevier Journal Backfiles on ScienceDirect 1907 - 2002
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    URL: http://linkinghub.elsevier.com/retrieve/pii/S0277-5387(00)83740-7
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  • 8
    Electronic Resource
    Electronic Resource
    Combustion Synthesis of Alumina-Based Multiphase Foam Ceramic (2008)
    s.l. ; Stafa-Zurich, Switzerland
    Key engineering materials Vol. 368-372 (Feb. 2008), p. 1526-1528 
    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: Al2O3-TiO-TiO2 multiphase foam ceramic was prepared with Al powders and TiO2 powders bycombustion synthesis, Direct observation and metallographic microscope indicated that the pore diameteris 100~6000μm, and Archimedean method showed that the porosity is 35~50%. The influencing factorsof the pore diameter and porosity and, the effects of adding SiO2 on compression strength of the Al2O3-TiO-TiO2 multiphase foam ceramic were discussed. It was shown that the addition of proper high temperaturefoaming agent can increase porosity and adding SiO2 can decrease porosity. The Al2O3-TiO-TiO2multiphase foam ceramic has good mechanical properties and high-temperature resistance
    Type of Medium: Electronic Resource
    URL: http://www.tib-hannover.de/fulltexts/2011/0528/01/56/transtech_doi~10.4028%252Fwww.scientific.net%252FKEM.368-372.1526.pdf
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  • 9
    Electronic Resource
    Electronic Resource
    Preparation of Ag Nanoparticles Colloid by Pulsed Laser Ablation in Distilled Water (2008)
    s.l. ; Stafa-Zurich, Switzerland
    Key engineering materials Vol. 373-374 (Mar. 2008), p. 346-349 
    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: The Ag nanoparticles colloid was prepared by pulsed laser ablation for different time in10 ml distilled water without any surface active agent, and it was analysed by means of UV-visiblespectrophotometer and transmission electron microscopy (TEM). The results showed that theablation efficiency and absorbance increased fast and shift to higher energies with increasingablation time from 5 to 10 min, then increased slowly from 10 to 20 min, and increased fast againfrom 20 to 25 min. The morphologies of most Ag nanoparticles were nearly spherical. The averagediameter and its distribution decreased from 5 to 7.5 min, then increased from 7.5 to 15 min, anddecreased from 15 to 25 min
    Type of Medium: Electronic Resource
    URL: http://www.tib-hannover.de/fulltexts/2011/0528/01/57/transtech_doi~10.4028%252Fwww.scientific.net%252FKEM.373-374.346.pdf
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  • 10
    Electronic Resource
    Electronic Resource
    Microstructure and Wear Response of Ni/SiC Laser Cladding Composite Coatings on a Carbon Steel (2008)
    s.l. ; Stafa-Zurich, Switzerland
    Key engineering materials Vol. 373-374 (Mar. 2008), p. 375-378 
    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: The high-energy laser melts the cladding materials which coagulate onto the surface ofthe base materials. The laser cladding coatings are produced mainly in two methods: powderfeeding and prefabricating. The grain-strengthening composite coatings could be formed moreeasily by prefabricating method than by powder feeding method. In this paper, Ni/SiC ceramiccomposite coating on carbon steel (45 steel) was made by prefabricating method. Themicrostructure and wear-resistance of Ni/SiC cladding coating on the 45 steel were studied usingscanning electronic microscope (SEM) and wear test. The results showed that the microstructure ofcladding coatings included bonding layer, thermo-affected layer and heat-affected layer after lasercladding. The microstructure of cladding coating was mainly of dendrite and cell-like crystals. Theresultant multilayered coating had excellent adherence with the base steel. The addition of SiCparticles into cladding coatings significantly reinforced the microhardness of laser cladding coating.Compared with Ni60A cladding coating, Ni60A/SiC cladding coating had high microhardness,which was attributed to not only the dispersion intensification effect of the SiC particle, but also bythe new complicated phases. During laser cladding process, SiC particles may decompose anddissolve into the coating and result in solid solution strengthening effect which increases themicrohardness of the composite coatings. The base material and Ni-based laser cladding coatingswith and without SiC were tested to assess the wear-resistance property. The test resultsdemonstrated that the laser cladding coatings had better wear resistance than the base material.Furthermore, the laser cladding coating with SiC particles had higher wear-resistance than thecoating without SiC
    Type of Medium: Electronic Resource
    URL: http://www.tib-hannover.de/fulltexts/2011/0528/01/57/transtech_doi~10.4028%252Fwww.scientific.net%252FKEM.373-374.375.pdf
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