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Tax burden outlier inhibits the growth of small and micro enterprises. This paper introduces the risk allocation of tax burden to measure the tax burden outlier. Using a time-varying nonparametric benchmark and path model, this paper measures the tax risk allocation of 3552 small and micro enterprises in the credit insurance fund from January 2016 to August 2018. This paper explores the configuration of tax burden risk allocation and discusses the changes along time and with the addition of other variables. Finally, this paper gives an analysis of strategies to improve tax burden risk allocation. The results provide decision support for reducing the tax burden and promoting the growth of small and micro enterprises.

Phthalonitrile containing benzoxazine (BA‐ph) and cyanate ester (CE) were chosen as the thermosetting matrix and the glass fiber (GF) reinforced laminates formed at low temperature were designed. The polyarylene ether nitriles containing pendent carboxyl groups (CPEN) was selected to modify the interfacial interaction between the resin matrix and GFs. Two methods of introducing CPEN were compared and the effects of CPEN on curing behaviors and properties of the composites were investigated. Results showed that with the CPEN, exothermic peaks shifted to lower temperature and curing temperatures of BA‐ph/CE decreased slightly. The mechanical and thermal properties of GF‐reinforced composites were discussed and the results indicated that the composites of modified GFs with CPEN exhibited outstanding mechanical properties, higher glass transition temperature (Tg > 290 °C) than that of composites composed of CPEN mixed with BA‐ph/CE. Moreover, GF‐reinforced composites showed stable dielectric constants (3.8–4.5) and low dielectric loss (0.005–0.01), which were independent of the frequency. In sum, the various methods of the introduction of CPEN in the GF‐reinforced composites may provide a new route to prepare improved composites, meanwhile, composites with outstanding processability and excellent mechanical and thermal properties are expected to be widely applied in the fields of high‐performance structural materials. © 2017 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2018, 135, 45881.

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Microwave absorbers with lightweight and excellent microwave absorption performance are urgently needed in microwave absorption field, which is still a challenge. Herein, N-doped carbon nanofibers decorated with nickel nanoparticles (Ni@CNFs)...