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The application of 3D printing in diverse industries is continuously on the increase because of its enormous benefits. However one drawback of using this techniques is the weak mechanical parts it produce. Recent studies have included carbonnanotubes (CNTs) into printed parts to improve strength using the DLP 3D techniques. Increasing the CNTs in nanocomposites decreases the mechanical properties as the CNTs absorb the UV-light irradiation meant for polymerization. This research consider basalt fillers as an alternative and CNTs/basalt hybrid reinforcement for better performance. A 5-20m long multiwall carbon nanotube of diameter 30nm and 10m chopped basalt fiber (BA) of diameter 10-19m were used as the reinforcements. A commercially available Phrozen nylon-like photoresin of viscosity 7mm2/s was used as the matrix. A Phrozen Shuffle 3D printer was used to print dog-bone specimens according to tensile test standard ASTM D638 for composites. Mono-fillers composites of 0.1 wt%CNT, 0.3wt%CNT and 0.1wt%BA, 0.3wt%BA were printed. Bi-fillers composites were printed by vary the CNTs from 0.05wt% to 0.2wt% and the Basalt fiber from 0.1wt% to 0.3wt%. Fillers were mixed with the resins by ultra-sonication method. Samples were characterized by performing mechanical tests with the MTS and decomposition thermal test was performed by the TGA. The Fourier transformation infra-red spectroscopy (FTIR) was used to evaluate double bond conversion and SEM instrument was used to characterize the fractured surface of each samples. Basalt mono-filler composite had better mechanical property than CNTs mono-filler composite. Increasing the wt% of CNTs in the hybrid composite decreases the tensile strength, elastic modulus and toughness while increasing wt% of basalt filler increases these properties. Composite samples with lower wt% of fillers had higher C=C conversion as UV-light could penetrate for greater level of polymerization resulting

Surface area plays an important factor in the energy conversion performance of solar cells. It has also emerged as a critical factor in the evolution of high-performance micro-electro-mechanical systems (MEMS) and multifunctional microstructures most of which will benefit from integrated on-chip solar power. Presented here is the hierarchical fabrication of TiO"2 nanotubes on non-planar 3-dimensional microstructures for enhanced performance of the photoanode in dye-sensitized solar cells (DSCs). The objective is to increase photoanode performance within a standard 1cm^2 lateral footprint area by increasing the vertical surface area through the formation of TiO"2 nanotubes on 3-D microstructures. In the interest of the seamless integration of DSCs into MEMS applications, careful attention is given to the processing methods of the 3-D surface enhanced photoanode. Bulk micromachining using wet-etching has been employed to fabricate 3-D microstructures in silicon. Anodization was used to form titania nanotubes within sputtered titanium thin films. Film quality, adhesion, and the formation of the nanotubes are discussed. Nanotubes with outer diameter dimensions of 180nm, inner diameter of 75nm, and heights of 340nm on [email protected]^[email protected] micro-wells have been fabricated resulting in more than 7times the increase in surface area over planar surfaces and a 20% reduction in surface spectral reflection.

We present on a carbon nanoparticle-filled SU-8 photosensitive polymer nanocomposite for use in microelectromechanical systems (MEMS) or microsystems. Exposure and fabrication of the material was carried out using X-ray lithography. The polymer nanocomposite was studied for its electrical, thermal and mechanical characteristics. It was found that at low filler weight percentages, the SU-8 polymer became electrically and thermally conductive. A comparative study of the lithography performance of this functionalized SU-8 to pure SU-8 was also performed. It was determined that UV lithography of the PNC was not suitable for thick films and that by using X-rays, thick film high-aspect-ratio microstructures were achievable. Such results are favorable for many applications such as monolithically integrated polymeric micro-resistive heating elements and polymeric micro-heat sinks.

The detection of saccharides in biological media is of great current importance for the monitoring of disease states. We have previously reported that solutions of boronic acid-functionalized macrocycles form acyclic oligomeric materials in situ. The oligomers contain fluorescent xanthene moieties. Current efforts are aimed at modulating the spectroscopic responses of these materials for the analysis of specific sugars. We describe conditions whereby the xanthene boronic acids exhibit high colorimetric fructose selectivity. In contrast, at physiological levels selective glucose monitoring can be achieved via fluorescence. Additionally, we describe a method which exhibits promise for detecting both glucose and fructose at dual wavelengths in the UV-Vis region. Mechanistic rationale for each of these findings is presented.

The determination of cysteine and homocysteine levels is of great current interest for the monitoring of desease states. A new colorimetric method for the simultaneous detection of l-cysteine and l-homocysteine has been developed. A fluorescein derivative reacts with the above amino acids, producing their respective thiazolidines resulting in color changes. Interference from other amino acids and proteins is minimal.