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The redox performances of 1–10 wt% Na-modified Fe 2 O 3 /Al 2 O 3 oxygen carrier from seawater were investigated using syngas/air as reactive gases in the thermogravimetric analyzer (TGA) and lab-scaled semi-fluidized bed reactor (semi-FzBR). NaNO 3(aq) as the source of sodium dopants to prepare Na-contained solution was implemented by an air atmospheric pressure plasma jet (Air-APPJ) process, which can increase the feasibility of seawater. For the prepared samples, the materials properties, including crystalline phases, surface morphologies, surface areas, and attrition loss performances were well correlated with the Na contents. The results indicated that the poor reduction kinetics and attrition resistance were obtained with the Na adjunction over 5 wt%, attributing to the sintering issue on excessive phases of Na 2 (Al, Fe) 12 O 19 and Na(Al, Fe)O 2 solid solution in the samples. Therefore, the slight incorporation of Na content in the Fe 2 O 3 /Al 2 O 3 samples which improved the reduction rate was proved as the candidate oxygen carriers. Particularly, the Na content with 1 wt% in Fe 2 O 3 /Al 2 O 3 sample (Na1FA32) can significantly promote the reduction behavior, thermal stability, and attrition resistance as compared to the raw Fe 2 O 3 /Al 2 O 3 oxygen carrier. It is environmentally beneficial to use the Na1FA32 as oxygen carrier in a practical chemical looping combustion process. [ABSTRACT FROM AUTHOR]

The use of seawater as catalytic agents for hematite (Fe 2 O 3 ) as oxygen carrier in chemical looping combustion process is attractive, because of its abundance and low cost. Unfortunately, seawater itself with major NaCl compound under reactive species accompanying the volatilization of chlorine-containing gases probably lead to the corrosion on reactors during the combustion process. In this study, the feasibility evaluation of sodium dopants extracted from seawater as an effective catalytic agent via an air atmospheric pressure plasma jet (Air-APPJ) is performed, and as such it is combined with Fe 2 O 3 /Al 2 O 3 to assess any possible enhancement on the reduction kinetics. The sodium-contained solutions, NaNO 3(aq) and NaCl (aq) , as precursors are used to prepare the sodium dopants due to the evaporation-decomposition of water and dissolved salts via plasma discharge reaction. The sodium-modified Fe 2 O 3 /Al 2 O 3 oxygen carrier can significantly promote the efficiency of the carbon capture efficiency and CO 2 yield. Especially for the NaCl (aq) as precursor in an Air-APPJ system, the high carbon capture efficiency, CO 2 molar fraction and CO 2 yield around 0.96, 0.95 and 0.91 after fifty redox cycle for the sodium-modified Fe 2 O 3 /Al 2 O 3 oxygen carrier are achieved. It can be anticipated that the sodium-modified Fe 2 O 3 /Al 2 O 3 from seawater by an Air-APPJ system as an oxygen carrier candidate in a reversible CLC process would be notably attractive. [ABSTRACT FROM AUTHOR]

Chronic brain stimulation has become a promising physical therapy with increased efficacy and efficiency in the treatment of neurodegenerative diseases. The application of deep brain electrical stimulation (DBS) combined with manganese-enhanced magnetic resonance imaging (MEMRI) provides an unbiased representation of the functional anatomy, which shows the communication between areas of the brain responding to the therapy. However, it is challenging for the current system to provide a real-time high-resolution image because the incorporated MnCl 2 solution through microinjection usually results in image blurring or toxicity due to the uncontrollable diffusion of Mn 2+ . In this study, we developed a new type of conductive nanogel-based neural interface composed of amphiphilic chitosan-modified poly(3,4 -ethylenedioxythiophene) (PMSDT) that can exhibit biomimic structural/mechanical properties and ionic/electrical conductivity comparable to that of Au. More importantly, the PMSDT enables metal-ligand bonding with Mn 2+ ions, so that the system can release Mn 2+ ions rather than MnCl 2 solution directly and precisely controlled by electrical stimulation (ES) to achieve real-time high-resolution MEMRI. With the integration of PMSDT nanogel-based coating in polyimide-based microelectrode arrays, the post-implantation DBS enables frequency-dependent MR imaging in vivo , as well as small focal imaging in response to channel site-specific stimulation on the implant. The MR imaging of the implanted brain treated with 5-min electrical stimulation showed a thalamocortical neuronal pathway after 36 h, confirming the effective activation of a downstream neuronal circuit following DBS. By eliminating the susceptibility to artifact and toxicity, this system, in combination with a MR-compatible implant and a bio-compliant neural interface, provides a harmless and synchronic functional anatomy for DBS. The study demonstrates a model of MEMRI-functionalized DBS based on functional neural interface engineering and controllable delivery technology, which can be utilized in more detailed exploration of the functional anatomy in the treatment of neurodegenerative diseases. [ABSTRACT FROM AUTHOR]

The possibility of using electric arc furnace dust (EAFD) as regenerable sorbents to adsorptive hydrogen sulfide was studied. To avoid the releasing of zinc vapor and leaching of heavy metal matter, the addition of Al 2 O 3 was used as inert stabilizer to suppress the volatilization of zinc vapor and generate a more stable chemical forms in EAFD. The results of redox behavior and toxicity characteristic leaching procedure show that Al 2 O 3 are excellent stabilizers for EAFD of industrial waste. Multi-cycle tests of sulfidation/regeneration showed that the prepared EAFD/Al 2 O 3 sorbents can be regenerated and thus reused after the regeneration process. After ten sulfidation/regeneration cycles, the sulfur capacity of the tenth cycle remained approximately on a level of 79% of the sulfur capacity in the first cycle. The results based on the material characterization and sulfidation/regeneration performance evaluation showed that EAFD/Al 2 O 3 sorbent has desirable physical and chemical properties for the desulfurization of simulated syngas at high-Temperature range. Therefore, EAFD with addition of Al 2 O 3 has a potential utilization for the removal of hydrogen sulfide. [ABSTRACT FROM AUTHOR]

Abstract: This study fabricated hydrogenated diamond-like carbon/silver bioceramic films on glass substrates using radio frequency magnetron sputtering with a single silver target in an atmosphere of Ar/CH4 mixture. The effects of applied power on the composition and microstructure of bioceramic film were evaluated. A phase transformation, amorphous diamond-like carbon → nano-silver precipitation → nano-silver growth in the amorphous diamond-like carbon matrix was observed during sputtering. The film growth rate, surface roughness, silver content and size of silver nanoclusters in the films all increased with the silver target power due to the higher flux of sputtered silver species toward the substrate. [Copyright &y& Elsevier]

Abstract In this study, a facile co-electrodeposition method has been developed to co-deposit iridium oxide and human plasma proteins. We use a cyclic voltammetry (CV) approach for co-electrodeposition on indium tin oxide-coated glass substrates. We adjust the percentages of plasma proteins as 1%, 3%, 5% and 7% to obtain different film thicknesses. We also optimize the number of cycles to achieve the ideal thickness. Cyclic voltammetry, field emission scanning electron microscopy, and Fourier-transform infrared spectroscopy were used for characterizing the deposited film. The results show that the plasma proteins can be successfully co-deposited with iridium oxide. The incorporation of plasma proteins results in an increase in the roughness of the film. The thickness of the electrodeposited layer is dependent on the concentration of plasma proteins. [ABSTRACT FROM AUTHOR]

Although traditional 3D scaffolds or biomimetic hydrogels have been used for tissue engineering and regenerative medicine, soft tissue microenvironment usually has a highly anisotropic structure and a dynamically controllable deformation with various biomolecule distribution. In this study, we developed a hierarchical hybrid gelatin methacrylate-microcapsule hydrogel (HGMH) with Neurotrophin-3(NT-3)-loaded PLGA microcapsules to fabricate anisotropic structure with patterned NT-3 distribution (demonstrated as striped and triangular patterns) by dielectrophoresis (DEP). The HGMH provides a dynamic biomimetic sinuate-microwrinkles change with NT-3 spatial gradient and 2-stage time-dependent distribution, which was further simulated using a 3D finite element model. As demonstrated, in comparison with striped-patterned hydrogel, the triangular-patterned HGMH with highly anisotropic array of microcapsules exhibits remarkably spatial NT-3 gradient distributions that can not only guide neural stem cells (NSCs) migration but also facilitate spinal cord injury regeneration. This approach to construct hierarchical 4D hydrogel system via an electromicrofluidic platform demonstrates the potential for building various biomimetic soft scaffolds in vitro tailed to real soft tissues. [Display omitted] [ABSTRACT FROM AUTHOR]

A technique was proposed to concentrate the distribution of set voltages. After a plasma treatment, the stability of the high-resistive state (HRS) increased, and the distribution of set voltages was more concentrated at 0.8 V, with a sufficient HRS/LRS resistive ratio (∼100x). In addition, the surface of the TiN electrode became rougher, causing oxygen to enter the TiN electrode and form a TiON layer, which acts as an oxygen reservoir. The reservoir is confirmed and the conduction model is supported by both electrical and material analyses. We propose that the observed improvement is due to the difference in the TiN electrode surface. Image 1 • Applied the plasma treatment on electrode to stabilize set voltage. • Construct the physical model to explain abnormal current conduction. • Complete electrical and material analysis were performed in this work. [ABSTRACT FROM AUTHOR]