Southwest University of Science and Technology

About: Southwest University of Science and Technology is a education organization based out in Mianyang, China. It is known for research contribution in the topics: Adsorption & Graphene. The organization has 10017 authors who have published 8923 publications receiving 94850 citations. The organization is also known as: Xīnán Kējìdàxué.

Core-Shell Al-Polytetrafluoroethylene (PTFE) Configurations to Enhance Reaction Kinetics and Energy Performance for Nanoenergetic Materials.

Abstract: The energy performance of solid energetic materials (Al, Mg, etc.) is typically restricted by a natural passivation layer and the diffusion-limited kinetics between the oxidizer and the metal. In this work, we use polytetrafluoroethylene (PTFE) as the fluorine carrier and the shielding layer to construct a new type of nano-Al based fuels. The PTFE shell not only prevents nano-Al layers from oxidation, but also assists in enhancing the reaction kinetics, greatly improving the stability and reactivity of fuels. An in situ chemical vapor deposition combined with the electrical explosion of wires (EEW) method is used to fabricate core-shell nanostructures. Studies show that by controlling the stoichiometric ratio of the precursors, the morphology of the PTFE shell and the energy performance can be easily tuned. The resultant composites exhibit superior energy output characters than that of their physically mixed Al/PTFE counterparts. This synthetic strategy might provide a general approach to prepare other high-energy fuels (Mg, Si).

High-Performance pH-Switchable Supramolecular Thermosets via Cation-π Interactions.

Abstract: Supramolecular chemistry has provided versatile and affordable solutions for the design of intelligent soft materials, but it cannot be applied in stiff materials. This paper describes a new concept for the design of high-performance supramolecular thermosets by using the noncovalent cation-π interaction as cross-linking. These supramolecular thermosets are a class of infusible and insoluble stiff polymers having excellent mechanical properties even at temperatures exceeding 300 °C. The cation-π interaction can be locally and reversibly installed and removed by aqueous treatments at high or low pH, respectively. Local manipulation of cross-linking confers these thermosets with multiple stimuli-responsive functions, such as recyclability, healability, adhesion, and nondestructive detection of cross-linking and mechanical properties.

Brain Image Segmentation Based on FCM Clustering Algorithm and Rough Set

Abstract: In this paper, a new image segmentation method is proposed by combining the FCM clustering algorithm with a rough set theory. First, the attribute value table is constructed based on the segmentation results of FCM under different clustering numbers, and the image is divided into several small regions based on the indistinguishable relationship of attributes. Then, the weight values of each attribute are obtained by value reduction and used as the basis to calculate the difference between regions and then the similarity evaluation of each region is realized through the equivalence relationship defined by the difference degree. Finally, the final equivalence relation defined by similarity is used to merge regions and complete image segmentation. This method is validated in the segmentation of artificially generated images, brain CT images, and MRI images. The experimental results show that compared with the FCM method, the proposed method can reduce the error rate and achieve better segmentation results for the fuzzy boundary region. And, the experimental results also prove that the algorithm has strong anti-noise ability.

Truncated titanium/semiconductor cones for wide-band solar absorbers.

Abstract: A truncated Ti and Si cones metasurface has been proposed for wide-band solar absorber (WSA), which produced a high average absorption of 94.7% in the spectral region from 500 to 4000 nm. A maximal enhancement factor of 166.0% was achieved by the WSA in comparison with the absorption of Ti/Si cylinder resonators based absorber. Under the standard solar radiance, a high full-spectrum solar absorption efficiency of 96.1% was obtained for the WSA in the energy range from 0.28 to 4.0 eV. The spectral bandwidth with absorption above 90% is up to 3.402 μm, which shows an enhancement factor of 165.0% than that of the WSA intercalated by the SiO2. Other semiconductors such as Ge, GaAs have been utilized to form the WSA, which also maintained the near-unity absorption in the wide-band spectrum. The plasmonic resonant response of the Ti material and the strong electromagnetic coupling capability of the Si resonator, and the plasmonic near-field coupling by the adjacent truncated cones were the main contributions for the impressive absorption behaviors. These findings pave a new way for achieving full-spectrum solar absorber via combining the Ti material and semiconductors, which could open potential approaches for active optoelectronic devices such as photo-detectors, hot-electron related modulators, and solar cells, etc.