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New hexamethylenetetramine complexes of antimony and bismuth trichloride were synthesized through a solid phase reaction of hexamethylenetetramine and antimony or bismuth trichloride. The formula of the complex is MCl3(C6H12N4)2⋅H2O (M=Sb, Bi).The crystal structure of the complexes belongs to monoclinic system and the lattice parameters: a=1.249 nm, b=1.4583 nm, c=1.6780 nm andβ=91.78° for SbCl3(C6H12N4)2⋅H2O and a=1.3250 nm, b=1.3889 nm, c=1.7449 nm and β=98.94° for BiCl3(C6H12N4)2⋅H2O. Far-infrared spectra reveal that the antimony or bismuth ion is coordinated by the nitrogen atom of the hexamethylenetetramine. The thermal analysis also demonstrates the complex formation between the antimony or bismuth ion and hexamethylenetetramine. The intermediate and final residues in the thermal decomposition process have been analyzed to check the pyrolysis reaction.

Based on the phenomenon that static electricity attracts dust, a polyethylene terephthalate (PET) semirigid sheet coated with printing ink was used to visualize impressions of fingerprints on the skin of living and dead bodies. Compared with visualization methods for perspiration fingerprints, this method recovers better images for a longer time after the fingerprint has been deposited on skin. Fingerprints transferred to the PET sheet are photographed with sidelighting using an ordinary light source. For fingerprints that yield inadequate contrast, an argon-ion laser can be used to improve the contrast.

High critical current density (Jc) and improved Jc-magnetic field dependence have been achieved in Ag-clad (Bi, Pb)2Sr2Ca2Cu3O10+x (2223) wires. Complex AC susceptibility measurements under DC magnetic fields have revealed that the irreversibility temperature scaled with the applied field according to H1/3, in contrast with YBa2Cu3O7-x but in accordance with bulk Bi-based and Tl-based materials. The presence of a fraction of highly dispersed 2212 appears to have a beneficial effect on flux pinning.

Aiming to improve pavement performance of polyacrylonitrile (PAN) fiber-asphalt mixture, five PAN fiber content was selected from 0% to 0.4% by 0.1% interval to evaluate the effect on the high temperature stability, crack resistance in low temperature and moisture stability of asphalt mixture. Then the enhancement mechanism of PAN fiber reinforcing asphalt mixture was revealed by SEM at the microscopic level. Based on the multi-index grey relational evaluation method, the optimum PAN fiber content is selected for the balance of both road performances and economic benefit. The results show that the PAN fiber significantly improves pavement performances of asphalt mixture, as it better infiltrates into the asphalt and forms higher interfacial strength. It also could be observed that the PAN fiber evenly distributed in the asphalt binder to form a spatial network structure, playing a significant role in bridging, reinforcement and toughening. When the amount of PAN fiber is 0.2%, the comprehensive performance of asphalt mixture is optimal on the basis of grey relational evaluation.

Three types of cement-stabilized macadam materials and raw materials mixed with a self-made early-strength agent were prepared and subjected to freeze-thaw cycle tests. Based on the unconfined compression and freeze-thaw cyclic tests, the compressive strength and mass loss rate, and frost resistance coefficients of these samples were assessed and compared. The change of material properties caused by different content of early-strength agent was analyzed. The results show that three kinds of early-strength agents can improve the compressive strength and freezing resistance of cement-stabilized macadam. The compressive strength of cement-stabilized macadam with 2.0% anhydrous sodium sulfate and 1.0% triethanolamine is the best; the compressive strength is increased by 73.8%. Cement-stabilized macadam material with 1.5% anhydrous sodium sulfate and 1.0% triethanolamine has the best frost resistance, and its mass loss rate is reduced by 0.733%. The curves of mass loss rate and freeze-thaw cycle times of four groups of material are established, and the trend of positive correlation between the content of anhydrous sodium sulfate and the freezing resistance is obtained.

The loss component of the susceptibility of a high quality Bi-2223/Ag tape in perpendicular ac field was measured as a function of the ac field amplitude and frequency and calculated using Maxwell’s equations and the critical state model. The calculations correctly predict the measured hysteresis and eddy current losses.