* a-zirconium phosphate (ZrP) (prepared by both reflux and hydrothermal methods) is silylated with chlorotrimethylsilane and characterized by X-ray diffraction, Fourier transform infrared spectroscopy and scanning electron microscopy. Polystyrene/silylated-ZrP composites show higher thermal stability as the ZrP content increases. Cone calorimetry suggests that the reduction of the peak heat release rate of polystyrene (PS)/ZrP composites does not increase as the ZrP loading increases; the aspect ratio of ZrP has little effect in fire performance of PS/ZrP composites.

In order to clarify questions raised from a recent study on the polymer/cerium (IV) oxide (CeO2) system, polystyrene/CeO2 was prepared by melt blending, which produces only microscale dispersed CeO2. The incorporation of CeO2 moderately enhances the thermal stability of the composites. Because of the limited surface area of microscale CeO2 particles compared with nanoscale particles, the microscale dispersed CeO2 induces negligible peak heat release rate reduction in cone calorimetry. Combination of CeO2 with organoclay does not show any advantages with either microdispersion of nanodispersion of CeO2 in polystyrene and polymethylmethacrylate matrices. In summary, the nanodispersion (i.e. surface area) of CeO2 particles is a critical factor in fire retardancy of the composites. Copyright © 2013 John Wiley & Sons, Ltd.

Background: Arthroscopic shavers play an indispensable role in arthroscopic debridement. They have exquisite structures and similar designs. The purpose of this study was to establish a reproducible testing protocol to compare the resection performance and the quality (tensile strength, torsional strength, and corrosion resistance) of different arthroscopic shavers with comparable designs. We hypothesized that there could be little difference in resection performance and quality between these shavers. Methods: Incisor Plus Blade (IPB; Smith & Nephew, Andover, MA) and Double Serrated Plus Blade (DSPB; BJKMC, Shanghai, China) were selected for resection performance and quality test. For resection performance testing, the resection torque, which is the minimum torque required to cut off silicone blocks with the same cross-sectional area, was measured to evaluate the resection performance of shaver blades when the other factors remain the same. For quality testing, tensile and torsion tests of the shavers' joint part were performed, and ultimate failure load and maximum torque were measured and compared. The corrosion resistance of these blades was assessed by the boiling water test based on the ISO13402. Results: No significant difference existed in the resection torque between the shaver blades of IPB and DSPB (P = 0.54). To the failure load of shavers' joint parts, IPB was significantly higher than DSPB, both in the outer and inner blades (P < 0.0001). The maximum torque of the joint part had no significant difference between IPB and DSPB (for inner blades P = 0.60 and outer blades P = 0.94). The failure load (for both IPB and DSPB P < 0.0001) and maximum torque (for IPB P = 0.0475 and DSPB P = 0.015) of the inner blades were higher than those of the outer blades. No blemishes were observed on the surface of the blades after corrosion resistance tests. Conclusions: This study provided some new methods to evaluate the resection performance and quality of different shavers. The resection performance, the torsional strength of the joint part, and the corrosion resistance of IPB and DSPB may show comparable properties, whereas the tensile strength of the shavers' joint part showed some level of difference.

This paper uses the panel data of A-share listed companies on the Shanghai and Shenzhen stock exchanges from 2008 to 2019 as the original sample and uses panel two-way fixed-effect, panel Tobit and mediation effect models to study the impacts of political connections of Chinese enterprises on the development of green innovation and the impact mechanism. The results show that political connections will inhibit the development of green innovation and have a greater inhibitory effect on the numbers of enterprises’ alternative energy patents and administrative supervision design patents. This conclusion persists under a series of robustness tests. Further analysis shows that the impact of enterprises’ political connections on green innovation has significant regional heterogeneity, and the inhibition of green innovation is mainly reflected in the manufacturing industry. In terms of mechanism, political connections influence green innovation capacity through the R&D investment and excessive debt of enterprises. Finally, the paper provides advice for the government to formulate policy and suggestions for enterprise development.