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In this work, a green emissive nanocomposite was synthesized by embedding nitrogen-doped carbon dots into hydrotalcite (N-CD/hydrotalcite) via a hydrothermal process for the recognition of latent fingerprints (LFPs).

Adsorption characteristics of Fe(III) ions onto thiocyanato-functionalized silica gel sorbent were investigated under various conditions of contact time, initial metal concentration and temperature. The equilibrium isotherms, kinetics and thermodynamics of Fe(III) ions adsorption onto the surface of thiocyanato-functionalized silica gel from aqueous solution were investigated. Batch kinetic studies showed that an equilibrium time of 30 min was required for the adsorption of Fe(III) ions onto thiocyanato-functionalized silica gel. The estimated maximum capacities of Fe(III) ions adsorbed by thiocyanato-functionalized silica gel were 112.2 mg g−1. The equilibrium adsorption data of thiocyanato-functionalized silica gel for Fe(III) ions best fitted to the Langmuir isotherm since the correlation coefficients for the Langmuir isotherm were higher than that for the Freundlich and Dubinin–Radushkevich isotherms. The kinetic data were well described by the pseudo-second-order model. Spontaneous, endothermic and random characteristics of the process were confirmed by thermodynamic analysis.

Adsorption of Sb(III) ions onto mercapto-functionalized silica-supported organic–inorganic hybrid sorbent from aqueous solutions was studied by a batch technique. The mercapto-functionalized hybrid sorbent was prepared via sol–gel method and characterized by Fourier transform infrared spectra and scanning electron microscopy coupled to an energy dispersive spectrometer. The effects of parameters (such as pH, contact time, initial concentration and temperature) on the adsorption of Sb(III) onto mercapto-functionalized hybrid sorbent were investigated. Mercapto-functionalized hybrid sorbent had a tendency toward higher adsorption affinity for Sb(III) compared with the Sb(V), a fast adsorption equilibrium time within 20 min, and a wide pH range (3–8) for Sb(III) adsorption. The Langmuir, Freundlich and Dubbin–Radushkevich isotherm models were applied to describe the equilibrium data of Sb(III) adsorption. The analysis of adsorption isotherms indicated that Langmuir model described well the equilibrium data of Sb(III) adsorption. The capacity of mercapto-functionalized hybrid sorbent for Sb(III) was found to be 108.8 mg g−1. The analysis of the kinetic data by the pseudo-first-order, pseudo-second-order, Elovich and intraparticle diffusion kinetic models revealed that pseudo-second-order model gave the best fit for Sb(III) adsorption. Thermodynamic parameters demonstrated that adsorption of Sb(III) ions onto mercapto-functionalized hybrid sorbent was an endothermic, spontaneous and thermodynamically feasible process. As the results indicated, mercapto-functionalized hybrid sorbent has a suitable potential for the removal of Sb(III) ions in practical process.

Aluminum foams were fabricated by melt-based route using ZrH2 as a foaming agent. The factors which affected the foaming of aluminum foams during casting process were investigated. The powdered zirconium hydride with content of 0.6%-1.4% (mass fraction) was added to the molten pure aluminum and the foaming condition was controlled in a temperature range from 933 to 1 013 K, Ca amount of 1.5%-3.0% (mass fraction), stirring time of 0.5-2.5 min and holding time of 1.5-4.0 min to obtain homogeneous aluminum foams. The fabricated aluminum foams were characterized by XRD, SEM and Image-pro plus. The mechanical properties of the aluminum foams with different relative density were tested. The result indicates that the foaming agent (ZrH2) is suitable for the preparation of small aperture aluminum foams with average pore diameter of 1 mm. Inter-metallic compounds and Al2O3 have effect on the melt viscosity. The aluminum foams experience linear elastic, platforms and densification process and had a higher efficiency of energy absorption.