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The ferromagnetism of Fe nanoparticle assembly on Al2O3∕NiAl(100) is observed above 150K with the coverage larger than 5 ML (monolayer). Cu capping layer induces an enhancement of the Curie temperature (TC) in both Fe and Co magnetic nanoparticle assembly. The TC of Fe nanoparticle assembly with 2 and 6 ML Cu capping layer is enhanced by ∼20K and even higher, indicating the critical effects of metallic capping layer in such magnetic nanostructures as nanoparticle assembly. The capping layer effect would be crucial for the ex situ measurements and the nanostorage-related applications.

Based on the systematic studies of the growth temperature, deposition rate, and annealing effects, the control of Co nanoparticle density, size, and alignment is demonstrated to be feasible on a nanostructured template Al2O3∕NiAl(100). At 140–170K, a slow deposition rate (0.027ML∕min) promises both the linear alignment and the high particle density. 1.5 ML Co nanoparticle assembly sustains the density of ∼260∕104nm2 even after 800–1090K annealing. This study also indicates the possibilities of the controlled growth for nanoparticles of different materials.

In this work, cow manure (CM) was reused as a potential precursor in the production of activated carbon (AC) using a potassium hydroxide activation process at different temperatures (i.e., 500, 600 and 700 °C). The optimal activated carbon from cow manure (CM-AC) with high specific surface area (ca. 950 m2/g) was further investigated for its adsorption performance in the removal of a model compound (i.e., methylene blue) from aqueous solution with various initial concentrations and adsorbent dosages at 25 °C. It was found that the resulting AC could be an effective adsorbent for removal of cationic dye from aqueous solution in comparison with a commercial coal-based AC. Based on the observations of the energy dispersive X-ray spectroscopy and Fourier transform infrared spectroscopy (FTIR), the CM-AC adsorbent has a stronger interaction with the cationic compound due to its more oxygen-containing complex on the surface. Furthermore, the adsorption kinetic parameters fitted using the pseudo-second order model with high correlations were in accordance with their pore properties.

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In this work, the thermochemical analyses of dairy manure (DM), including the proximate analysis, ultimate (elemental) analysis, calorific value, thermogravimetric analysis (TGA), and inorganic elements, were studied to evaluate its potential for producing DM-based char (DMC) with high porosity. The results showed that the biomass should be an available precursor for producing biochar materials based on its high contents of carbon (42.63%) and volatile matter (79.55%). In order to characterize their pore properties, the DMC products produced at high pyrolysis temperatures (500–900°C) were analyzed using surface area and porosity analyzer, pycnometer, and scanning electron microscopy-energy dispersive X-ray spectroscopy (SEM-EDS). The values of pore properties for the DMC products increased with an increase in pyrolysis temperature, leading to more pore development and condensed aromatic cluster at elevated temperatures. Because of the microporous and mesoporous structures from the N2 adsorption–desorption isotherms with the hysteresis loops (H4 type), the Brunauer–Emmett–Teller (BET) surface area of the optimal biochar (DMC-900) was about 360 m2/g, which was higher than the data reported in the literature. The highly porous structure was also seen from the SEM observations. More significantly, the cation exchange capacity (CEC) of the optimal DMC product showed a high value of 57.5 ± 16.1 cmol/kg. Based on the excellent pore and chemical properties, the DMC product could be used as an effective amendment and/or adsorbent for the removal of pollutants from the soil media and/or fluid streams.

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