Many reactive metals are difficult to prepare in pure form without complicated and expensive procedures. Although titanium has many desirable properties (it is light, strong and corrosion-resistant), its use has been restricted because of its high processing cost. In the current pyrometallurgical process--the Kroll process--the titanium minerals rutile and ilmenite are carbochlorinated to remove oxygen, iron and other impurities, producing a TiCl4 vapour. This is then reduced to titanium metal by magnesium metal; the by-product MgCl2 is removed by vacuum distillation. The prediction that this process would be replaced by an electrochemical route has not been fulfilled; attempts involving the electro-deposition of titanium from ionic solutions have been hampered by difficulties in eliminating the redox cycling of multivalent titanium ions and in handling very reactive dendritic products. Here we report an electrochemical method for the direct reduction of solid TiO2, in which the oxygen is ionized, dissolved in a molten salt and discharged at the anode, leaving pure titanium at the cathode. The simplicity and rapidity of this process compared to conventional routes should result in reduced production costs and the approach should be applicable to a wide range of metal oxides.

This work reports the supercapacitive properties of electrochemically grown composite films of multiwalled carbon nanotubes (MWNT) and polypyrrole (PPy), a conducting polymer. Scanning electron microscopy, cyclic voltammetry, and electrochemical impedance spectroscopy revealed that the nanoporous three-dimensional arrangement of PPy-coated MWNTs in these films facilitated improved electron and ion transfer relative to pure PPy films. The low-frequency capacitance was measured for films of varying thickness, revealing specific capacitances per mass (C mass) and geometric area (C area) as high as 192 F g-1 and 1.0 F cm-2, respectively. Rates of charge and discharge about an order of magnitude faster than similarly prepared pure PPy films were also observed.

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the plane surface and the diffusion rate decreases with decreasing pore size. With decreasing pore size, the pH gradient at the bottom of the pore, which is imposed by the electroreduction of protons, increases. Therefore, the growth rate of the nanowire is enhanced as the pore size decreases.In conclusion, we have investigated the growth of singlecrystal CdS nanowires using electrochemically induced deposition in the pores of an AAO template from acidic chemical baths containing CdCl 2 and TAA. TEM and HREM investigations indicated that these nanowires have a uniform hexagonal CdS single-crystal structure and the {100} surfaces of the CdS crystals are parallel to the axes of the nanowires. The above results imply that the growth of the nanowire may be influenced profoundly by different electrochemical processes. ExperimentalThe AAO templates with pore sizes of about 8, 20, and 90 nm were grown by potentiostatic anodization of high-purity aluminum plates (0.15 mm thick, 99.9+ % purity) in aqueous solutions of 14 % H 2 SO 4 and 4 % and 2 % oxalic acid, respectively, at 0±20 C. After the anodization, the remaining aluminum was etched by a 20 % HCl±0.1 M CuCl 2 mixed solution. Then the barrier layer was dissolved using 20 % H 2 SO 4 . Finally, a silver film was deposited by vacuum evaporation onto one surface of the template membrane to provide a conductive contact.The deposition of CdS was performed potentiostatically at a potential value of ±0.65 V referred to the saturated calomel electrode (SCE) in a three-electrode configuration in a glass cell at 70 C by immersing the cell in a water bath for 5±8 h. A platinum plate, SCE, and the Ag/AAO substrate were used as counter, reference, and working electrodes, respectively. The electrolyte solution consisted of 0.05 M CdCl 2 and 0.10 M TAA, as in the work by Yamaguchi et al. [25]. In order to avoid the erosion of the template, the initial pH of this mixture was adjusted to 4.6 by adding appropriate amounts of HCl. In all cases, the electrolyte was freshly prepared and heated for 1 h at 70 C prior to each deposition. After the deposition, the nanowires in the AAO templates were ultrasonically washed in water for 1 min, rinsed with double distilled water, and finally dried in air at room temperature before being subjected to further analysis.AAO was completely removed from the Ag/AAO/CdS samples by mounting the foil on a glass using epoxy resin and then dissolving the AAO template in 1 M NaOH at 25 C for 1 h and washing several times with double distilled water. For transmission electron microscopy (TEM), the nanowires were detached from the substrate by being ultrasonically dispersed in 1 cm 3 water, then a small drop of the solution was placed on a Cu grid covered with carbon film. A transmission electron microscope, JEM-200CX, operated at 160 keV and fitted with X-ray energy dispersion analysis equipment (EDAX 9100/6, Philips), was employed to study the morphology of the nanowires. For the high-resolution electron microscopy (HREM) observations, a JEOL-2010 electron ...

Receptor-tyrosine-kinase-like orphan receptor 1 (ROR1) is expressed during embryogenesis and by certain leukemias, but not by normal adult tissues. Here we show that the neoplastic cells of many human breast cancers express the ROR1 protein and high-level expression of ROR1 in breast adenocarcinoma was associated with aggressive disease. Silencing expression of ROR1 in human breast cancer cell lines found to express this protein impaired their growth in vitro and also in immune-deficient mice. We found that ROR1 could interact with casein kinase 1 epsilon (CK1ε) to activate phosphoinositide 3-kinase-mediated AKT phosphorylation and cAMP-response-element-binding protein (CREB), which was associated with enhanced tumor-cell growth. Wnt5a, a ligand of ROR1, could induce ROR1-dependent signaling and enhance cell growth. This study demonstrates that ROR1 is expressed in human breast cancers and has biological and clinical significance, indicating that it may be a potential target for breast cancer therapy.

Most methods for improving supercapacitor performance are based on developments of electrode materials to optimally exploit their storage mechanisms, namely electrical double layer capacitance and pseudocapacitance. In such cases, the electrolyte is supposed to be electrochemically as inert as possible so that a wide potential window can be achieved. Interestingly, in recent years, there has been a growing interest in the investigation of supercapacitors with an electrolyte that can offer redox activity. Such redox electrolytes have been shown to offer increased charge storage capacity, and possibly other benefits. There are however some confusions, for example, on the nature of contributions of the redox electrolyte to the increased storage capacity in comparison with pseudocapacitance, or by expression of the overall increased charge storage capacity as capacitance. This report intends to provide a brief but critical review on the pros and cons of the application of such redox electrolytes in supercapacitors, and to advocate development of the relevant research into a new electrochemical energy storage device in parallel with, but not the same as that of supercapacitors.

Nanoscale microelectrochemical cells can form on individual carbon nanotubes in neutral aqueous solutions of KMnO4, leading to corrosion of the nanotubes (see image) and simultaneous deposition of nanocrystalline MnO2 on both external and internal surfaces of the nanotubes.