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Abstract: An easy method is described for the synthesis of a mesostructured Ni/ordered mesoporous carbon (OMC) composite with a highly ordered cubic structure (space group Im3m). This synthesis was carried out by the carbonization of the F127/[Ni(H2O)6](NO3)2/RF (resorcinol-formaldehyde) composite self-assembled in an alkaline medium. The effects of nickel loading content and carbonization temperature on the morphologies, pore features, structures and magnetic properties of these Ni/OMC composites were investigated using the thermogravimetric analysis, X-ray diffraction, nitrogen sorption, transmission electron microscopy and vibrating-sample magnetometer measurements. It was found that Ni2+ was captured by the network of F127/RF and further reduced into metallic Ni nanoparticles during the carbonization. The nickel nanoparticles were well-dispersed in the ordered mesoporous carbon walls. The Ni/OMC composites exhibit the soft ferromagnetic behavior and the magnetization parameters can be adjusted by the content of nickel and the carbonization temperatures. The excellent acid-resistant property of the magnetic materials makes them useful in magnetic separation. [Copyright &y& Elsevier]

Atomic layer deposition of high quality Al2O3 thin films onto Au electrodes was enabled by surface modification with a self-assembled monolayer of -OH groups that react with a monolayer of trimethylaluminum gas source. Ar ion milling was then used to expose the edge of the Au/insulator/Au structure for molecular electrode contacts. The junctions are characterized by atomic force microscope and tunnel current properties. The Au/self-assembled monolayer/Al2O3/Au tunnel junction, with a very thin oxide insulator layer (15.4 Å), is stable and has a small tunneling current density of about 0.20-0.75 A/cm2 at 0.5 V. [ABSTRACT FROM AUTHOR]

We report a 4.3 µm mid-infrared (mid-IR) high-power amplified spontaneous emission (ASE) fiber source based on CO 2 -filled nested hollow-core anti-resonant fiber (Nested HC-ARF). The pump source is a homemade hundred-watt-level wavelength-tunable 2 µm single-frequency fiber laser. A 5.7 m long 8-tube Nested HC-ARF is used as the gas cell, with a core diameter of 110 µm and cladding diameter of 400 µm, which exhibits transmission loss of 0.1 dB/m at 2 µm and 0.24 dB/m at 4.3 µm respectively. To improve the coupling efficiency of the high-power pump laser and reduce the influence of the thermal effect at the input end of the hollow-core fiber, the fiber is designed for multimode transmission at the pump wavelength. A continuous wave output power of 6.6 W at 4.3 µm is achieved, and the slope efficiency is 17.05%. To the best of our knowledge, it is the highest output power for such gas-filled HC-ARF ASE sources in 4∼5 µm. This work demonstrates the great potential of gas-filled HC-ARF generating high-power mid-IR emission.