Shape memory effect and mechanical properties of carbon nanotube/shape memory polymer nanocomposites

ArticleCOMPOSITE STRUCTURES. 81(2): 176-184 (2007)journal articl

Charging mechanism in a SiO 2 matrix embedded with Si nanocrystals

One of the applications of a Si nanocrystals (nc-Si) embedded in a Si O2 matrix is in the area of nonvolatile memory devices based on the charge storage in the material system. However, whether the charge trapping mainly occurs at the nc-SiSi O2 interface or in the nc-Si is still unclear. In this work, by x-ray photoemission spectroscopy analysis of the Si 2p peaks, the concentrations of both the nc-Si and the Si suboxides that exist at the nc-SiSi O2 interface are determined as a function of thermal annealing, and the charging effect is also measured by monitoring the shift of the surface C 1s peak. It is observed that the annealing-caused reduction of the total concentration of the interfacial suboxides is much faster than that of both the C 1s shift and the nc-Si concentration. In addition, the trend of the C 1s shift coincides with that of the nc-Si concentration. The results suggest that the Si nanocrystal, rather than the nc-SiSi O2 interface, plays the dominant role in the charging effect. © 2006 American Institute of Physics.published_or_final_versio

The expression patterns of nogo-A, myelin associated glycoprotein and oligodendrocyte myelin glycoprotein in the retina after ocular hypertension : the expression of myelin proteins in the retina in glaucoma

Nogo-A, a major myelin inhibitory protein, inhibits axon growth and synaptic function in the central nervous system. Glaucoma is a progressive neuropathy as a result of retinal ganglion cell (RGC) death. Synaptic degeneration is thought to be an early pathology of neurodegeneration in glaucoma and precedes RGC loss. Here experimental ocular hypertension model was induced in adult rats with laser coagulation of the episcleral and limbal veins. The expression of Nogo-A, myelin-associated glycoprotein (MAG) and oligodendrocyte myelin glycoprotein (OMgp) in the retina was investigated using immunohistochemistry and Western blotting. We found that Nogo-A was expressed in the RGCs and upregulated after the induction of ocular hypertension. OMgp was only expressed in the inner plexiform layer. There was no MAG expression in the retina. Our data provided, for the first time, the expression patterns of three myelin proteins in the adult retina and suggested an important role of Nogo-A in the RGC death and synaptic degeneration in glaucoma. © 2011 Springer Science+Business Media, LLC.postprin

Novel ZnO nanorod films by chemical solution deposition for planar device applications

: Smooth and continuous ZnO films consisting of densely packed ZnO nanorods (NRs) were synthesized using hydro-thermo-chemical solution deposition method which can be used for electronic device fabrication. These devices would have the novelty of high performance benefiting from the unique properties of the nanomaterials and can be fabricated on these films using conventional low cost planar process, as they have very smooth surfaces. Photoluminescence measurements showed that the nanorod films have much stronger band-to-band emissions than those from discrete ZnO NRs, hence have the potential for the development of ZnO light emission diodes and lasers etc. The nanorod films have been used to fabricate large area planar surface acoustic wave devices by conventional photolithography and demonstrated two well-defined resonant peaks and their potential for large area device applications. The chemical solution deposition method is a simple, reproducible, scalable and economic method. These nanorod films are suitable for large scale production and synthesis on cost-effective substrates promising for various fields such as sensing systems, renewable energy and optoelectronic applications

Concentrated vertical jetting mechanism for isotropically focused Zno/Si surface acoustic waves

This paper investigates vertical droplet jetting using circular surface acoustic wave (CSAW) devices with annular interdigitated transducers (AIDTs) fabricated on ZnO film coated silicon substrate. The surface vibration on the CSAW devices was simulated using finite element analysis and characterised using laser vibrometry. Results showed that focused wave patterns and compact nodal distributions of vibration were formed at the centre of ZnO/Si CSAW device, which is contrast to an anisotropic wave distribution patterns generated by the same pattern of AIDTs fabricated on 128° Y-cut LiNbO3. Simulation of liquid jetting induced by the isotropically focused CSAW was performed using coupled Volume of Fluid and Level-Set method. Results showed that a sharp and cylindrical liquid column was generated from the ZnO/Si CSAW device induced by acoustic energy coming from all directions within the plane due to the in-plane isotropic nature of the ZnO thin films. The simulation enabled us to capture the different streaming/jetting processes induced by the anisotropic distributions of acoustic pressure generated by the AIDTs on the 128° Y-cut LiNbO3 CSAW device. The concentrated vertical droplet jetting behaviour from the ZnO/Si CSAW devices was investigated experimentally and supported the simulated results

Vertically aligned smooth ZnO nanorod films for planar device applications

The growth of smooth and continuous zinc oxide (ZnO) films, consisting of densely packed vertical ZnO nanorods with (002) crystal orientation on silicon substrates has been achieved in this work by a chemical solution method. These ZnO thin films have much stronger photoluminescence emission than those from discrete ZnO nanorods under identical conditions. Large area surface acoustic wave devices were fabricated on these films using conventional photolithography, and exhibited two well-defined resonant modes of the Sezawa wave and its harmonic mode

Human pluripotent stem cell-derived mesenchymal stem cells prevent allergic airway inflammation in mice.

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Near-Infrared Super Resolution Imaging with Metallic Nanoshell Particle Chain Array

We propose a near-infrared super resolution imaging system without a lens or a mirror but with an array of metallic nanoshell particle chain. The imaging array can plasmonically transfer the near-field components of dipole sources in the incoherent and coherent manners and the super resolution images can be reconstructed in the output plane. By tunning the parameters of the metallic nanoshell particle, the plasmon resonance band of the isolate nanoshell particle red-shifts to the near-infrared region. The near-infrared super resolution images are obtained subsequently. We calculate the field intensity distribution at the different planes of imaging process using the finite element method and find that the array has super resolution imaging capability at near-infrared wavelengths. We also show that the image formation highly depends on the coherence of the dipole sources and the image-array distance.Comment: 15 pages, 6 figure