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101.
102.
V.A. Smalyuk O.A. Hurricane J.F. Hansen G. Langstaff D. Martinez H.-S. Park K. Raman B.A. Remington H.F. Robey O. Schilling R. Wallace Y. Elbaz A. Shimony D. Shvarts C. Di Stefano R.P. Drake D. Marion C.M. Krauland C.C. Kuranz 《High Energy Density Physics》2013,9(1):47-51
Kelvin–Helmholtz (KH) turbulent mixing measurements were performed in experiments on the OMEGA Laser Facility [T.R. Boehly et al., Opt. Commun. 133 (1997) 495]. In these experiments, laser-driven shock waves propagated through low-density plastic foam placed on top of a higher-density plastic foil. Behind the shock front, lower-density foam plasma flowed over the higher-density plastic plasma. The interface between the foam and plastic was KH unstable. The experiments were performed with pre-imposed, sinusoidal 2D perturbations, and broadband 3D perturbations due to surface roughness at the interface between the plastic and foam. KH instability growth was measured using X-ray, point-projection radiography. The mixing layer caused by the KH instability with layer width up to ~100 μm was observed at a location ~1 mm behind the shock front. The measured mixing layer width was in good agreement with simulations using a K–L turbulent mixing model in the two-dimensional ARES hydrodynamics code. In the definition of the K–L model K stands for the specific turbulent kinetic (K) energy, and L for the scale length (L) of the turbulence. 相似文献
103.
ATOP dyes. optimization of a multifunctional merocyanine chromophore for high refractive index modulation in photorefractive materials. 总被引:2,自引:0,他引:2
F Würthner S Yao J Schilling R Wortmann M Redi-Abshiro E Mecher F Gallego-Gomez K Meerholz 《Journal of the American Chemical Society》2001,123(12):2810-2824
This paper reports synthesis, characterization and structural optimization of amino-thienyl-dioxocyano-pyridine (ATOP) chromophores toward a multifunctional amorphous material with unprecedented photorefractive performance. The structural (dynamic NMR, XRD) and electronic (UV/vis, electrooptical absorption, Kerr effect measurements) characterization of the ATOP chromophore revealed a cyanine-type pi-conjugated system with an intense and narrow absorption band (epsilon(max) = 140 000 L mol(-)(1) cm(-)(1)), high polarizability anisotropy (deltaalpha(0) = 55 x 10(-)(40) C V(-)(1) m(2)), and a large dipole moment (13 D). This combination of molecular electronic properties is a prerequisite for strong electrooptical response in photorefractive materials with low glass-transition temperature (T(g)). Other important materials-related properties such as compatibility with the photoconducting poly(N-vinylcarbazole) (PVK) host matrix, low melting point, low T(g), and film-forming capabilities were optimized by variation of four different alkyl substituents attached to the ATOP core. A morphologically stable PVK-based composite containing 40 wt % of ATOP-3 showed an excellent photorefractive response characterized by a refractive index modulation of Deltan approximately 0.007 and a gain coefficient of Gamma approximately 180 cm(-)(1) at a moderate electrical field strength of E = 35 V microm(-)(1). Even larger effects were observed with thin amorphous films consisting of the pure glass-forming dye ATOP-4 (T(g) = 16 degrees C) and 1 wt % of the photosensitizer 2,4,7-trinitro-9-fluorenylidene-malononitrile (TNFM). This material showed complete internal diffraction at a field strength of only E = 10 V microm(-)(1) and Deltan reached 0.01 at only E = 22 V microm(-)(1) without addition of any specific photoconductor. 相似文献
104.
B. Ormsby G. Foster T. Learner S. Ritchie M. Schilling 《Journal of Thermal Analysis and Calorimetry》2007,90(2):503-508
After improvements were made to a modified Polymer Labs MkIII DMTA instrument to facilitate repeatable controlled humidity
(RH) experiments using isothermal and thermal scanning conditions, the viscoelastic properties of titanium white pigmented
artists’ acrylic emulsion films were measured in tensile mode. The effects of temperature, relative humidity and accelerated
ageing regimes on two brands of titanium white paints were explored. These paints are highly responsive to changes in temperature
and relative humidity, formulation differences affect properties slightly, and while light ageing had a negligible effect,
thermal ageing resulted in decreased storage modulus and increased film density. 相似文献
105.
F. Schilling O. Schumm Carlson Weehuizen A. Bolland J. G. van der Horst Weinberger Walter Giese Tagayamo L. Lewin A. Miethe E. Stenger A. Partheil M. Neisser H. Sachs L. van Itallie C. Arnold und G. Werner 《Fresenius' Journal of Analytical Chemistry》1909,48(10):660-664
Ohne Zusammenfassung 相似文献
106.
Polycrystalline copper and monocrystalline iron were tribomechanically loaded in a defined way. By fundamentals of a continuum mechanical analysis of the stress field and a transmission electron microscopical investigation of the dislocation arrangement conclusions were made regarding the crack nucleation, the crack propagation and the wear resistance. The proved development of a dislocation cell structure is an adaptation of the material to the friction loading to tolerate a high number of loading cycles without wear. 相似文献
107.
In a recent letter, new representations were proposed for the pair of sequences (,), as defined formally by Bailey in his famous lemma. Here we extend and prove this result, providing pairs (,) labelled by the Lie algebra AN – 1, two nonnegative integers and k and a partition , whose parts do not exceed N – 1. Our results give rise to what we call a higher level Bailey lemma. As an application it is shown how this lemma can be applied to yield general q-series identities, which generalize some well-known results of Andrews and Bressoud. 相似文献
108.
H.B. Banks W. Bi L. Sun G.F. Chen X.H. Chen J.S. Schilling 《Physica C: Superconductivity and its Applications》2011,471(15-16):476-479
The ac susceptibility of single crystalline tetragonal EuFe2As2, EuFe2As1.4P0.6, and EuFe1.715Co0.285As2 has been measured over the temperature and hydrostatic (He-gas) pressure ranges 10–60 K and 0–0.8 GPa, respectively. For all three samples the magnetic ordering temperature (17–19 K) from the Eu sublattice increases linearly with pressure, presumably due to the enhanced exchange coupling between Eu-layers. No evidence for a superconducting transition was observed in the susceptibility for any sample over the measured temperature/pressure range. 相似文献
109.
Wolfgang Vautz Ludwig Schwarz Chandrasekhara Hariharan Michael Schilling 《International Journal for Ion Mobility Spectrometry》2010,13(3-4):121-129
The major uncertainty related to ion mobility spectrometry is the lack of knowledge about the characteristics of the ions detected. When using a radioactive atmospheric pressure ionisation source (e.g. 63Ni), from theory proton bound water clusters are expected as reactant ions. When analyte ions occur, proton transfer should lead to proton-bound monomer and dimer ions. To increase the knowledge about those ionisation processes in an ion mobility spectrometer (IMS), a ß-radiation ionisation source was coupled to a mass spectrometer (MS) and an identical one to an IMS. Exemplarily, acetone, limonene and 2- and 5-nonanone were introduced into both instruments in varying concentrations. By correlating the MS and IMS spectra, conclusions about the identities of the ions detected by IMS could be drawn. Proton-bound monomer, dimer and even trimer ions (MH+, 2MH+, 3MH+) could be observed in the MS spectra for acetone and 5-nonanone and could be assigned to the related signals detected by IMS. The oligomers could be expected from theory for increasing concentration. Limonene and 2-nonanone yielded in a variety of different ions and fragments indicating complex gas phase ion chemistry. Those findings on the obviously different behaviour of different analytes require further research focussed on the ion chemistry in IMS including the comparison of different ionisation sources. 相似文献
110.
We perform event-driven molecular dynamics simulations of a system composed by uniaxial hard ellipsoids for different values of the aspect ratio and packing fraction. We compare the molecular orientational-dependent structure factors previously calculated within the Percus-Yevick approximation with the numerical results. The agreement between theoretical and numerical results is rather satisfactory. We also show that, for specific orientational quantities, the molecular structure factors are sensitive to the particle shape and can be used to distinguish prolate from oblate ellipsoids. A first order theoretical expansion around the spherical shape and a geometrical analysis of the configurations confirms and explains such an observation. 相似文献