Effect of a Magnetic Field on the Electrode Process of Al Electrodeposition in a [Emim]Cl-AlCl3 Ionic Liquid.

The magnetohydrodynamic (MHD) effect was usually used to improve the mass transport during electrodeposition in a solution electrolyte. Herein, we reported the effect of a magnetic field on the electrode process of Al electrodeposition in a [Emim]Cl-AlCl3 ionic liquid composed of pure ions. Under a uniform and perpendicular magnetic field to the Cu electrode plane, electrochemical impedance spectroscopy (EIS) of the circuit, the cyclic voltammetry (CV) curves, and the different capacitances at the potential of zero charge (PZC) were measured, and the electrodeposition of aluminum was carried out at a constant current density. The results indicated that a vertical magnetic field significantly reduced the resistance (activation energy) for charge transfer of electrochemical reduction of Al2Cl7-; meanwhile, the capacitance of an electric double layer (EDL) and the density of the electrodeposited aluminum layer were increased.

Preliminary study on the electromagnetic field treatment of osteoporosis in rats.

OBJECTIVE: In our study, the influence of PEMF on skeleton morphology and bone metabolism on rats with disuse osteoporosis was investigated, and the possibility of using it for the treatment of disuse osteoporosis was explored. METHODS: The rats in the ALN group were treated with alendronate, and the rats in the PEMF group were exposed to pulsed electromagnetic fields (3.82 mT, 10 Hz) for 40 mind-1. Rats were sacrificed by the end of 2, 4, 8 and 12 weeks, and serum and right leg bones were collected. Serum BMP-2, BGP concentrations and bone metabolism and biomechanical parameters were measured. RESULTS: The bone structural mechanical indices and material mechanical indices of the right femur in all groups of mice during weeks 2 and 4 were decreased. At week 8 the bone structural mechanical index and maximum stress of the right femur in the ALN group were markedly raised compared with the CON group (P< 0.01). Only maximum stress and strain were improved in the ALN group and had a significant difference (P< 0.05) at week 12. The serum BGP and BMP-2 concentration in the PEMF and ALN groups was increased (P< 0.05) at week 2, but this increase was not synchronized. After 8 weeks, BGP and BMP-2 level in the PEMF group was observably elevated (P<0.01) in contrast to the ALN group. CONCLUSION: From the experimental time interval analysis, PEMF can improve the mechanical stability of bone structure more gently and permanently than alendronate.

Carbonization of transition metals in molten salts.

The carbonization of transition metals in molten salts was performed to study the effect of electrochemical polarization and molten salt medium on the carbonization process. The carbonization of niobium (Nb) has been systemically investigated in Ar atmosphere and molten salts. The effect of particle size and structure of the starting materials, molten salt medium, and electric field on the formation of NbC was studied to reveal the dynamic barriers in the carbonization process. A native oxide layer and/or niobate derivatives generated on the Nb particles are the main barriers for the mass transfer of carbon and Nb towards each other. The results showed that molten salts can accelerate the formation of NbC by enhancing the diffusion of carbon, and the kinetic barrier can be effectively eliminated by supplying negative polarization to the cathode in molten salts to remove the oxide barriers, thereby enhancing carbonization. Besides Nb, tungsten (W), molybdenum (Mo), titanium (Ti), and tantalum (Ta) can also be carbonized in molten salts with the assistance of an applied electric field.

Extraction of Co and Li2CO3 from cathode materials of spent lithium-ion batteries through a combined acid-leaching and electro-deoxidation approach.

Recycling of the spent LIBs to extract Li and Co not only offers raw materials for batteries but also lays a sustainable way for battery development. Herein, we adopt a route combining hydrometallurgical and pyro-electrochemical routes to extract Li2CO3 and Co powder from the spent LIBs of cell phones. The LiCoO2-based cathode materials were firstly dissolved in H2SO4 solution containing H2O2 as the reductant, and the optimal conditions for attaining a high extraction rate of 99% were studied. After that, the precipitated Co(OH)2 was calcinated in air under 500 °C to generate Co3O4 which was thereafter electrochemically converted into Co powder and oxygen in molten Na2CO3-K2CO3. Overall, the hybrid method employing both hydro- and pyro-route provides an effective pathway to recover both Li2CO3 and Co powder from spent LIBs.

Preparation and Antibiofilm Properties of Zinc Oxide/Porous Anodic Alumina Composite Films.

The PAA (porous anodic alumina) films were prepared by two-step anodic oxidation after different times, and then the ZnO/PAA composite films were prepared by sol-gel method on their surface. Meanwhile, the ZnO/PAA composite films were characterized by X-ray diffraction (XRD), thermogravimetric/differential thermal analyzer (TG/DTA), Fourier transform infrared spectrometer (FT-IR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), selected area electron diffraction (SAED), and water contact angle (CA). The antibiofilm properties of ZnO/PAA composite films on Shewanella putrefaciens were measured simultaneously. The results show that the micromorphologies of PAA and ZnO/PAA composite films are affected by second anodization time. ZnO is a hexagonal wurtzite structure, and ZnO particles with a diameter of 10-30 nm attach to the inner or outer surfaces of PAA. After being modified by Si69, the ZnO films translate from hydrophilia to hydrophobicity. The ZnO/PAA film with the optimal antibiofilm properties is prepared on the PAA surface by two-step anodization for 40 min. The adherence of Shewanella putrefaciens is restrained by its super-hydrophobicity, and the growth of biofilm bacteria is inhibited by its abundant ZnO particles.

Electrochemical Synthesis of Core-Shell-Structured NbC-Fe Composite Powder for Enforcement in Low-Carbon Steel.

An NbC-Fe composite powder was synthesized from an Nb2O5/Fe/C mixture by electrochemical reduction and subsequent carbonization in molten CaCl2-NaCl. The composite has a core-shell structure, in which NbC acts as the cores distributing in the Fe matrix. A strong bonding between NbC and Fe is benefit from the core-shell structure. The sintering and electrochemical reduction processes were investigated to probe the mechanism for the reactions. The results show that NbC particles about several nanometers were embraced by the Fe shell to form a composite about 100 nm in size. This featured structure can feasibly improve the wettability and sinterability of NbC as well as the uniform distribution of the carbide in the cast steel. By adding the composite into steel in the casting process, the grain size of the casted steel was markedly deceased from 1 mm to 500 µm on average, favoring the hardening of the casted steel.

Molecular characterization of a novel gene from Synechocystis sp. PCC 6803.

A novel gene slr2049 was identified in Synechococcus sp. PCC7002 by homologous alignment. The features and possible functions of slr2049 gene were predicted by bioinformatics analysis. The function of slr2049 was analyzed in vitro with a heterologous Escherichia coli system with plasmids conferring biosynthesis of phycocyanobilin (PCB) and of the acceptor proteins, ß-phycocyanin (CpcB). The resulting products were evaluated with SDS-PAGE and absorption spectra. The function of slr2049 was further analyzed via site-directed mutations. Two mutants, slr2049 (W14L) and slr2049 (Y132S) were generated. The results showed that Slr2049 could catalyze the chromophorylation of CpcB. Compared to wild type, mutant Slr2049 (W14L) had red-shifted absorbance maxima and was not highly fluorescent as the wild-type. However, mutant Slr2049 (Y132S) was almost the same as the wild-type. In conclusion, our study suggests that we have cloned a novel gene and this gene may play an important role in attachment of the chromophores to the apo-proteins.