Using molecular dynamics calculations we demonstrate that with decreasing the thickness of ultrathin body-centered-cubic (bcc) α-Fe film with (001) surfaces, the biaxial strain results in first bcc(001) &rarr fac...
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Femtosecond laser ablation studies of silicon with and without the native oxide on the surface were conducted in an ultrahigh vacuum environment. SEM results show a clear difference in the laser intensity threshold fo...
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Numerical and experimental studies are performed on thermal fluid-flow transport phenomena around a heating wire set on the free surface of a liquid cavity. Emphasis is placed on the effects of the Marangoni number, M...
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A numerical study is performed to investigate steady-state thermal and fluid flow transport phenomena of the vertical free jet, which is placed to the surface with the longitudinal convex curvature. Emphasis is placed...
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The microemulsion AEO-9/butanol/ cyclohexane/nitrate aqueous solution (or ammonium salt aqueous so lution) was studied, which was used as 'micro-reactor'in preparing long afterglow phosphor materials SiAI(?)O4...
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The microemulsion AEO-9/butanol/ cyclohexane/nitrate aqueous solution (or ammonium salt aqueous so lution) was studied, which was used as 'micro-reactor'in preparing long afterglow phosphor materials SiAI(?)O4:Eu2+, Dy3+.The phase behavior of microemulsion was *** radius of inner water droplet R and the change of standard free energy (?)G(?) were obtained by means of dilution method and theoretical calculation The result shows that with the increase of W/S,the area of microemulsion region decreases, R(?) and (?)G(?) increase and the microemul sion stability *** structure change and formation area of microemulsion AEO-9/butanol/*** aqueous solution (or ammonium salt aqueous solution) were offered for the adoption of a synthesis method with newly high efficiency and *** particular size and its distribution theory gist, fluorescence life span,and quenching concentration parameter data were expected. A new approach was explored for finding a new preparation method of rare earths afterglow materials and increasing luminescence intensity without crashing.
Long afterglow SrAl2O4: Eu2+ ,Dy3+ phosphor was synthesized by microemulsion method. The synthesized phosphor was characterized by XRD. XRD pattern indicates that the phosphor has monoclinic SrAl2O4 crystal structure....
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Long afterglow SrAl2O4: Eu2+ ,Dy3+ phosphor was synthesized by microemulsion method. The synthesized phosphor was characterized by XRD. XRD pattern indicates that the phosphor has monoclinic SrAl2O4 crystal structure. The microstructure of the phosphor was investigated by SEM and TEM. The excitation spectrum, emission spectrum and afterglow decay curve were measured, the wide range of excitation wavelength indicated that the luminescent material could be excited by the light from ultraviolet ray to visible light, and the emission maximum was found to peak mainly at λem of 525 nm. The sample excited by ultraviolet visible light could emit bright green light.
Poly(methyl methacrylate) (PMMA) was used to wrap alumina siloxane sol through emulsion polymerization. A kind of suspensions with notable ER effect was produced by fully mixing the prepared microcapsule with silicon...
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Poly(methyl methacrylate) (PMMA) was used to wrap alumina siloxane sol through emulsion polymerization. A kind of suspensions with notable ER effect was produced by fully mixing the prepared microcapsule with silicon oil. Meanwhile a series of PMMA wrapped alumina-siloxane gel doped with rare earths was obtained and its ER effect was tested, like viscosity of different rare earth ion doped samples in different powder concentrations and at different temperatures, at the same time, leak current density and dielectric constant were measured. Results show that the ER effect of this suspension is remarkable, and its stability is much better. The condition of emulsion polymerization and the mechanism of effect are discussed.
作者：
R. S. LakesDepartment of Engineering Physics
Engineering Mechanics Program Materials Science Program University of Wisconsin 147 ERB 1500 Engineering Drive Madison Wisconsin 53705
Composites with negative stiffness inclusions in a viscoelastic matrix are shown to have higher stiffness and mechanical damping tanδ than that of either constituent and exceeding conventional bounds. The causal mech...
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Composites with negative stiffness inclusions in a viscoelastic matrix are shown to have higher stiffness and mechanical damping tanδ than that of either constituent and exceeding conventional bounds. The causal mechanism is a greater deformation in and near the inclusions than the composite as a whole. Though a block of negative stiffness is unstable, negative stiffness inclusions in a composite can be stabilized by the surrounding matrix. Such inclusions may be made from single domains of ferroelastic material below its phase transition temperature or from prebuckled lumped elements.
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