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A free-standing plate-type plasmon-enhanced Z-scheme photocatalytic system has been established viaCdS deposition on Au-decorated BiVO4nanoplates (CdS/Au on BiVO4). Through the enhancement from in-plane plasmon resonant energy transfer of gold, the hydrogen evolution rate of CdS/Au on BiVO4was enhanced about 7.7 times higher than that of the gold-free photocatalyst.

In a general view of anatomy, intervertebral disc is composed of three parts: annulus fibrosus (AF), nucleus pulposus (NP), and cartilage endplate (CEP). Recently, several types of stem cells were successfully isolated from these corresponding regions, but up to now, no research was performed about which kind of stem cells is the most efficient candidate for NP tissue engineering or for stem cell-based disc regeneration therapy. In this study, we compared the regenerative potentials of the above-mentioned three kinds of disc-derived stem cells with that of the classic bone marrow (BM)-mesenchymal stem cells (MSCs) in a rabbit disc degeneration model. By magnetic resonance imaging (MRI), X-ray, histology, etc. evaluations, we found that cartilage endplate-derived stem cells (CESCs) showed superior capacity compared with the annulus fibrosus-derived stem cells (AFSCs), nucleus pulposus-derived stem cells (NPSCs), and BM-MSCs (p<0.05); additionally, when comparing the CESC group with the normal control group, there existed no statistical difference in X-ray (p>0.05). Those results demonstrated that the CESC-seeded alginate construct performed the most powerful ability for NP regeneration, while AFSCs showed the most inferior potency, NPSCs and BM-MSCs had similar regenerative capacity and located in the middle. All in all, our study showed that CESCs might act as an efficient seed cell source for NP tissue engineering, which paved a new way for the biological solution of disc degeneration diseases.

A fabrication of ZnO hierarchical mesocrystal was achieved by a biomimetic method using gelatin as structure-directing agent. It was found that the ZnO−gelatin microcrystal with well-defined hexagonal twin plate shape is built by the stacking of nanoplates. The irregularly edged nanoplates can adjust themselves to each other throughout the microcrystal, resulting in a roughly hexagonal edge. Selected area electron diffraction (SAED) analysis of the ZnO−gelatin microcrystal demonstrates that all the stacked nanoplates are aligned and oriented to form a single-crystal structure with hexagonal symmetry. The hierarchical structure of ZnO was found to resemble that of naturally occurring nacre. Similar to nacreous architecture, the nanoplate of ZnO was constructed from the oriented attachment of ZnO nanoparticles. More importantly, the lattices of the stacked nanoplates are aligned through mineral bridges between neighboring plates. A mechanism scheme is proposed for the formation of the gelatin−ZnO hybrid hierarchical structure. The preserved hexagonal shape of the mesocrystal structure consequently results in a whispering gallery mode (WGM) of optical emission where light was confined in the hexagons by total internal reflection. The observation of WGM mode emission in the ZnO hexagon structure shows promises for nanoscale fabrication of optoelectronic devices.

AbstractThe objective of this study is to develop an innovative compositive impregnation process for preparing sulfurized powdered activated carbon (PAC) from waste tires. An experimental apparatus, including a pyrolysis and activation system and a sulfur (S) impregnation system, was designed and applied to produce sulfurized PAC with a high specific surface area. Experimental tests involved the pyrolysis, activation, and sulfurization of waste tires. Waste-tire-derived PAC (WPAC) was initially produced in the pyrolysis and activation system. Experimental results indicated that the Brunauer-Emmett-Teller (BET) surface area of WPAC increased, and the average pore radius of WPAC decreased, as water feed rate and activation time increased. In this study, a conventional direct impregnation process was used to prepare the sulfurized PAC by impregnating WPAC with sodium sulfide (Na2S) solution. Furthermore, an innovative compositive impregnation process was developed and then compared with the conventional direct impregnation process. Experimental results showed that the compositive impregnation process produced the sulfurized WPAC with high BET surface area and a high S content. A maximum BET surface area of 886 m2/g and the S content of 2.61% by mass were obtained at 900°C and at the S feed ratio of 2160 mg Na2S/g C. However, the direct impregnation process led to a BET surface area of sulfurized WPAC that decreased significantly as the S content increased.