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排序方式: 共有922条查询结果,搜索用时 15 毫秒
1.
Stefano Mariani Antonino Amedeo La Mattina Alessandro Paghi Lucanos Strambini Giuseppe Barillaro 《Advanced functional materials》2021,31(26):2100774
Here, a fluoride-assisted route for the controlled in-situ synthesis of metal nanoparticles (NPs) (i.e., AgNPs, AuNPs) on polydimethylsiloxane (PDMS) is reported. The size and coverage of the NPs on the PDMS surface are modulated with time and over space during the synthetic process, leveraging the improved yield (10×) and faster kinetics (100×) of NP formation in the presence of F− ions, compared to fluoride-free approaches. This enables the maskless preparation of both linear and step gradients and patterns of NPs in 1D and 2D on the PDMS surface. As an application in flexible plasmonics/photonics, continuous and step-wise spatial modulations of the plasmonic features of PDMS slabs with 1D and 2D AgNP gradients on the surface are demonstrated. An excellent spatially resolved tuning of key optical parameters, namely, optical density from zero to 5 and extinction ratio up to 100 dB, is achieved with AgNP gradients prepared in AgF solution for 12 minutes; the performance are comparable to those of commercial dielectric/interference filters. When used as a rejection filter in optical fluorescence microscopy, the AgNP-PDMS slabs are able to reject the excitation laser at 405 nm and retain the green fluorescence of microbeads (100 µm) used as test cases. 相似文献
2.
L. A. Kosyachenko I. M. Rarenko E. F. Sklyarchuk I. I. German Sun Weiguo 《Semiconductors》2006,40(5):554-557
Photodiodes designed to be sensitive in the region 0.5–1.7 μm and obtained by vacuum magnetron sputtering of the ITO (SnO2 + In2O3) layer on the surface of the Hg3In2Te6 single crystal are studied. The electrical characteristics, measured at 265–333 K, indicate that the mechanism of charge
transport in the diodes under study is thermionic. The current-voltage characteristic and its temperature variations are described
quantitatively based on the energy diagram and the found parameters of the heterojunction.
Original Russian Text ? L.A. Kosyachenko, I.M. Rarenko, E.F. Sklyarchuk, I.I. German, Sun Weiguo, 2006, published in Fizika
i Tekhnika Poluprovodnikov, 2006, Vol. 40, No. 5, pp. 568–571. 相似文献
3.
Colzato Lorenza S.; Raffone Antonino; Hommel Bernhard 《Canadian Metallurgical Quarterly》2006,32(3):705
Four experiments were conducted to investigate the relationship between the binding of visual features (as measured by their aftereffects on subsequent binding) and the learning of feature-conjunction probabilities. Both binding and learning effects were obtained, but they did not interact. Interestingly, (shape-color) binding effects disappeared with increasing practice, presumably because of the fact that only 1 of the features involved was relevant to the task. However, this instability was only observed for arbitrary, not highly overlearned combinations of simple geometric features and not for real objects (colored pictures of a banana and strawberry), where binding effects were strong and resistant to practice. These findings suggest that learning has no direct impact on the strength or resistance of bindings or on speed with which features are bound; however, learning does affect the amount of attention particular feature dimensions attract, which again can influence which features are considered in binding. (PsycINFO Database Record (c) 2011 APA, all rights reserved) 相似文献
4.
A defect-free, two-material component can be obtained via co-sintering by suitably altering the powder characteristics or compositions, as demonstrated in Part I. In this paper, a model to ascertain the suitability of material systems to be co-sintered without defects such as delamination or interface pores is presented. The model is based on the management of the stress induced due to the difference in shrinkage and an analysis of the in situ strength of the weaker material during sintering. Tool steel in combination with stainless steel admixed with boron and Fe-2Ni admixed with boron are two systems used to validate the model. The predictions of the model are in good agreement with the observations. 相似文献
5.
6.
The spectral transmittance of mixed silver-halide polycrystalline fibres was measured while they were undergoing repeated
bending leading to mechanical fatigue. Microscopic mechanical defects were detected through their influence on the optical
losses, without interfering with the deformation. Optical and mechanical lifetimes of the fibres were found to depend on the
composition and to be larger for highly-mixed compositions. Scanning electron microscopy observations of fatigued fibres revealed
a strong influence of the fibre composition on the fatigue damage. This dependence on the composition was explained using
a theoretical model of solid-solution strengthening.
This revised version was published online in November 2006 with corrections to the Cover Date. 相似文献
7.
8.
Deborah C. Blaine John D. Gurosik Seong Jin Park Randall M. German Donald F. Heaney 《Metallurgical and Materials Transactions A》2006,37(3):715-720
Sintering experiments with various molybdenum powders are rationalized using a master sintering curve concept that collapses
density, grain size, or other parameters onto a single curve. In this case, the integral work of sintering is developed and
customized for different green densities. Construction of the master sintering curve is described to show how the curve can
be normalized with respect to green density effects. Various grades of molybdenum for metal injection molding and die compaction
are included in the analysis, processed over a range of heating cycles. Die-compacted samples of varying green densities are
used to illustrate the efficacy of the new, normalized master sintering curve concept. Sintering cycle optimization is one
possible outcome from this analysis. 相似文献
9.
Latexes with intrinsic crosslink activity 总被引:1,自引:0,他引:1
In order to develop and study ‘two pack in one pot’ systems, i.e. binder systems consisting of a blend of complementary reactive latexes, epoxy- and amino-functional latexes were prepared and characterised, with atte lion especially directed to control of the number of functional groups and control of the molecular weight. The investigation is focused on the control of the molecular weight of epoxy-functional latexes and on the incorporation of amino groups in latexes by using amino-functional methacrylic monomers. To determine the reactivity of the epoxy and amino groups and to check which factors influence the crosslink reaction a number of blends were prepared from both solution and emulsion copolymers and dried at ambient temperatures. It was found that the major factors, which affect the efficiency of crosslinking, are the Tg and the molecular weight of the copolymers and, in the case of a ‘two pack in one pot system’, the rate of the polymer-polymer reaction in relation to that of the polymer-polymer interdiffusion. 相似文献
10.
A. Hammiche L. Bozec† H. M. Pollock M. German & M. Reading‡ 《Journal of microscopy》2004,213(2):129-134
Near‐field photothermal Fourier transform infra‐red microspectroscopy, which utilizes atomic force microscopy (AFM)‐type temperature sensors, is being developed with the aim of achieving a spatial resolution higher than the diffraction limit. Here we report on a new implementation of the technique. Sensitivity of the technique is assessed by recording infra‐red spectra from small quantities of analytes and thin films. A photothermomechanical approach, which utilizes conventional AFM probes as temperature sensors, is also discussed based on preliminary results. Early indication suggests that the photothermal approach is more sensitive than the thermomechanical one. 相似文献