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101.
赵青南 《武汉理工大学学报(材料科学英文版)》2005,(4)
1Introduction Theultravioletrays(UV)insunlight(-4%)cantransmitintoroomthroughcommonfloatglass,theUVcanmakethematerialsintheroom,eg,paper,furni ture,textilefabricandplastics,becoloredanddeterio rated.ShieldingfromUVirradiationisofinterestinmanyfields.Formu… 相似文献
102.
103.
Hong-hui YuJohn W Hutchinson 《Thin solid films》2003,423(1):54-63
Delamination of residually stressed thin film strips is analyzed to expose the dependence on strip width and film/substrate elastic mismatch. Isotropic films and substrates are assumed. The residual stress in the film is tensile and assumed to originate from mismatch due to thermal expansion or epitaxial deposition. Full and partial delamination modes are explored. In full delamination, the interface crack extends across the entire width of the strip and releases all the elastic energy stored in the strip as the crack propagates along the interface. The energy release rate available to propagate the interface crack is a strong function of the strip width and the elastic modulus of the film relative to that of the substrate. The energy release rate associated with full delamination is determined as a function of the interface crack length from initiation to steady-state, revealing a progression of behavior depending in an essential way on the three dimensionality of the strip. The dependence of the energy release rate on the remaining ligament as the interface crack converges with the strip end has also been calculated, and the results provide an effective means for inferring interface toughness from crack arrest position. A partial delamination propagates along the strip leaving a narrow width of strip attached to the substrate. In this case, the entire elastic energy stored in the strip is not released because the strain component parallel to the strip is not relaxed. A special application is also considered, in which a residually stressed metal superlayer is deposited onto a polymer strip. The energy release rate for an interface crack propagating along the interface between the polymer and the substrate is determined in closed form. 相似文献
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Structural and electrical properties of brush plated ZnTe films 总被引:1,自引:0,他引:1
Zinc telluride thin films were deposited by the brush plating technique at a potential of −0.90 V (SCE) on conducting glass and titanium substrates at different temperatures in the range 30–90 °C. The films were polycrystalline in nature with peaks corresponding to the cubic phase. Direct band gap of 2.30 eV was observed. XPS studiers indicated the formation of ZnTe. Depth profiling studies indicated a uniform distribution of Zn and Te throughout the entire thickness. EDAX measurements were made on the films and it was found that there was a slight excess of Te. The carrier concentration was found to vary from 1014–1015 cm−3 with increase of substrate temperature. The mobility was found to vary from 5 to 60 cm2 V−1 s−1. 相似文献
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A two‐phase flow CFD model using the volume of fluid (VOF) method is presented for predicting the hydrodynamics of falling film flow on inclined plates, corresponding to the surface texture of structured packing. Using the proposed CFD model the influence of the solid surface microstructure, liquid properties and gas flow rate on the flow behavior was investigated. From the simulated results it was shown that under the condition of no gas flow the liquid flow patterns are dependent on the microstructure of the plates, and proper microstructuring of the solid surface will improve the formation of a continuous liquid film. It was also found that liquid properties, especially surface tension, play an important role in determining the thin‐film pattern. However, there are very different liquid film patterns under the action of gas flow. Thinner liquid films break easily, but thicker liquid films can remain continuous even at higher gas flow rates, which demonstrates that all factors affecting the liquid film thickness will affect the liquid film patterns under conditions of counter‐current two‐phase flow. 相似文献
110.
K. Gunnarsson P.E. Roy S. Felton J. Pihl P. Svedlindh S. Berner H. Lidbaum S. Oscarsson 《Advanced materials (Deerfield Beach, Fla.)》2005,17(14)
Structured magnetic surfaces enabling programmable motion of single micrometer‐sized magnetic particles are reported on p. 1730 by Gunnarsson and co‐workers. Patterns of thin‐film magnetic elements are tailored to form transport lines with junctions for the separation of individual particles. This method has the potential to improve and generate new applications in biotechnology. The cover shows a schematic of the transportation and separation of magnetic particles functionalized with antibodies capable of selectively capturing the corresponding analytes from a sample. 相似文献