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Thermo-sensitive microemulsion-based gels (MBGs) were prepared by the addition of Pluronic P123 (PEO20PPO70PEO20) into O/W microemulsion composed of isopropyl myristate (IPM)/Span20/Tween20/H2O. The results of rheological measurements indicate that the viscoelastic properties of the systems increase and the gelation temperatures decrease with increasing P123 concentration. Fluorescence spectroscopy was used to study the micropolarity of the hydrogel (P123/H2O), microemulsion and MBGs systems. The results show that the microstructures of microemulsion droplets are maintained in MBGs.

Pure titanium (Ti) which had been processed by high energy ball milling, graphite and Ni60A self-melting alloy composite powder were used as the cladding materials. A test on the in situ synthesized graded TiC particulate reinforced Ni-based composite coating was carried out after presetting of the composite powder on the 42CrMo alloy structured steel base surface. Morphologies, tissue structures and microhardness values of samples were investigated by an optical microscope (OM), scanning electron microscope (SEM) and microhardness tester. Results show that in situ synthesis of TiC reinforced particulates is realized with pure Ti and graphite powder under laser cladding. TiC particulates which have a small density presents a graded distribution of less at lower and more at upper of the coating due to the floating effect in a melting pool. Therefore, in situ synthesized graded TiC particulate reinforced Ni-based composite coating was gained. Moreover, TiC particulates cluster and grow in the melting pool due to collision and bonding of TiC particulates in the floating process. Compared to TiC particulates at lower part of the coating, the TiC particulates at upper part of the coating possess a higher proportion of clusters and growth phenomena. The volume percentage of TiC particulates at middle and bottom of the composite coating is lower than 5%, while volume percentage of TiC particulates on the coating surface is no higher than 25%. Similar with distribution pattern of TiC particulates, microhardness of the composite coating is also high on surface and low deep layer of the coating.

In this paper, triphosgene respectively reacting with o-nitrophenyl aniline, m-nitrophenyl aniline and p-nitrophenyl aniline to synthesize corresponding isocyanates. The effects of reactants molar ratio, reaction time and reaction temperature on the yield were investigated. As a result, using 1,2-dichloroethane as reaction solvent, the optimum molar ratio of the three kinds of nitroaniline and triphosgene were all 2.5:1, the optimum reaction time of synthesis of o-nitrophenyl isocyanate, m-nitrophenyl isocyanate and p-nitrophenyl isocyanate respectively was 6h, 5.5h and 5h; the optimum reaction temperature of synthesis of the three kinds of nitrophenyl isocyanates were all 75°C. Under the optimal conditions, the yield of o-nitrophenyl isocyanate, m-nitrophenyl isocyanate and p-nitrophenyl isocyanate could respectively be 80.3%, 83.7% and 83.5%. The products were characterized by meltingtest, ebulliometry, IR, and HPLC