A comparative study of the third-order nonlinear optical properties, via the newly developed heterodyned optical Kerr effect (OHD-OKE) measurements, of silver phenylacetylide and related compounds is reported. [AgC[triple bond]CC(6)H(5)](n) (1) was found to exhibit efficient third-order nonlinear optical susceptibility chi((3)) of 2.4 x 10(-14) esu, and second hyperpolarizability gamma of 9.07 x 10(-32) esu. These results are compared with those of two related silver phenylacetylide compounds, namely, a double salt, (silver phenylacetylide).(silver tert-butylthiolate) [AgC[triple bond]CC(6)H(5).AgS(t-C(4)H(9))](n) complex (2), and a cluster, triphenylphosphine silver phenylacetylide tetramer, [(C(6)H(5))(3)PAgC[triple bond]CC(6)H(5)](4) (3), as well as that of the related organic polymer polyphenylacetylene (4). These four compounds represent different types of phenylacetylide derivatives: 1 is an organometallic polymer, 2 a polymeric double salt, 3 a discrete metal cluster, and 4 an organic polymer. It was found that the third-order optical nonlinear response was enhanced by the incorporation of silver d electrons into the delocalized conjugated organic pi system, and its magnitude is highly dependent upon the extent of the pi delocalization. Specifically, the relative magnitudes of chi((3)) and gamma follow the order silver phenylacetylide polymer (1) > (silver phenylacetylide).(silver tert-butylthiolate) double salt (2) > polyphenylacetylene polymer (4) > tetrameric (triphenylphosphine silver phenylacetylide)(4) cluster (3). The observed trend may be attributed to the decreasing length of pi conjugation. It is interesting to note that the incorporation of Ag(I) into the polymeric framework of polyphenylacetylene enhances the chi((3)) by 25-fold for the same degree of polymerization (n = 7). The signs of chi((3)) and gamma, which are related to the response mechanisms, were found to be solvent dependent.

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A major challenge in chemical engineering is the separation and purification of materials, especially of rare earth compounds. It has been reported that a dielectrophoretic (DEP) apparatus can be used for separating rare earth oxides. The DEP capture of REOs on screen electrode was observed with microscope. The concentration of ROEs was determined using a nephelometer and ICP-OES before and after injection into the DEP apparatus. The results show that three types of REOs, La2O3, CeO2 and Dy2O3, generate nDEP in the DEP capture apparatus. There are two factors: voltage and suspension concentration, that affect the capture rate. The capture rate increases as voltage rises within certain limits. The capture rate also increases with increase in the original suspension concentration. Different REOs show marked differences in the DEP capture conditions. Consequently, factors such as voltage and flow rate can be controlled to achieve separation of different REOs.

Monodisperse nickel phosphide (Ni5P4) nanoparticles supported on carbon (Ni5P4@C) were in situ synthesized by one step solution-phase route, in which the mixture of trioctyloxide (TOPO) and trioctylphosphine (TOP) was used as solvent, capping agent and phosphor source. Ni5P4nanocrystals were in situ coupled by active carbon simply adding the carbon to the reaction solution. The as-prepared Pt-free Ni5P4 nanocrystals exhibit the enhanced electrocatalytic activity toward hydrogen oxidation reaction (HOR) compared to pure commercial Ni nanoparticles. Therefore, the obtained Ni5P4@C nanocatalyst appears to be promising non precious metal electrocatalysts for HOR.

A novel and high efficient PbO2 electrode has been fabricated in the present study for refractory wastewater treatment. The traditional Ti plate is made into honeycomb by electronic corrosion to be used as electrode basement. The novel surface topography improves the specific surface area of the electrode material and enhances the adhesion of surface coating. SnO2-Sb layer is deposited between basement and PbO2 layer which reduces the thermal stress and improve electrode life. Rare earth element La is doping into PbO2 layer to improve the lattice structure and the catalytic performance. Finally, F ion is adding into the catalytic layer to improve the smoothness of the material surface. Characterized by SEM and XRD, results showed that the electrode prepared has novel surface morphology. Pollutants degradation results and electrode life test showed that the PbO2 electrode investigated in the present study has great advantage compared with traditional electrodes and has good application prospect.