Modeling and characterization of the electrical conductivity on metal nanoparticles/carbon nanotube/polymer composites.

Flexible conductive films have good deformability and conductivity, and are expected to be used in flexible electronic devices. In this paper, four kinds of flexible conductive films were successfully prepared by compounding nano-sized metal (Ni, Cu, Au or AuCu alloy) particles to CNT surface and then dispersing to polydimethylsiloxane matrix. Experiment results show that the conductivity of these prepared films are almost two orders of magnitude higher than that of CNT/polydimethylsiloxane films with the same CNT loadings. A simulation model based on percolation network theory and Monte Carlo technology is introduced to study the influence of nanoparticles on the composite conductivity. Results confirmed that the introduction of nanoparticles effectively reduces the effective resistance of CNT and the tunnelling resistance at CNT junctions. The intrinsic conductivity and the length diameter ratio of CNT, the intrinsic conductivity, the size and the coverage ratio of nanoparticles are the core parameters affecting the conductivity of composite. Compared with CNT/polydimethylsiloxane films, the optimized theoretical conductivity of these nano-sized particles enhanced composites can be further improved.

[Clinical observation on treatment of rheumatoid arthritis by combined therapy with methotrexate, sulfasalazine and Chinese herbal medicine].

OBJECTIVE: To observe the effect of Fengshi No. 1 (FS1) in treating patients with active stage of rheumatoid arthritis (RA). METHODS: Patients with RA were randomly divided into two groups, the 40 patients in the treated group were treated with combined therapy of methotrexate (MTX), sulfasalazine (SSZ) and FS1, and the 20 in the control groups were treated with MTX and SSZ alone. RESULTS: In the treated group, the total effective rate was 97.5%, the clinical controlled and markedly effective rate 95.0% and the occurrence rate of side-toxic reaction 10.0%, as compared with those in the control group, 60.0%, 20.0% and 45.0% respectively, the difference was significant (chi 2 = 11.91, 32.23 and 7.67 respectively, all P < 0.01). The effect in the treated group was superior to that in the control group in abating joint swelling and pain, improving function of joint, reducing immune indices and ameliorating iconographic features (P < 0.01 or P < 0.05). CONCLUSION: FS1 not only has the effects of anti-inflammation, analgesis, regulating immune reaction, but also could retard the occurring of bone destruction, reduce the toxic-side effects of MTX and SSZ.