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This study uses a dynamic slacks‐based measure (SBM) model in a data envelopment analysis (DEA) framework with surplus reserve and accounts receivable as desirable and undesirable indicators respectively, based on inter‐connectivity between consecutive periods to estimate the operating efficiency of 110 listed Chinese real‐estate companies in the first step analysis. The results show that 35 listed real‐estate companies in China operated on the efficient frontier by maintaining sustainable growth throughout the entire period. The analysis presents the projection of indicators to suggest a feasible solution to improve the inefficient terms. At the second step analysis, using ordinary least square (OLS) estimation, authors find a curve‐linear relationship between real‐estate company size and efficiency to suggest that operating efficiency increases as size also increases due to economies of scale but only up to an optimum point. Profitability and higher education are also identified as the other significant determinants of operating efficiency. The findings of this research present evidence that average efficiency scores vary over time and generally comove with China's economic growth rate and the average stock returns in the real‐estate sector. By providing a new framework for evaluating input, output and carry‐over indicators of real‐estate companies, the results of this study equip real‐estate companies to have an accurate perspective of their operating position and simultaneously provide investors with an avenue to evaluate real‐estate companies' development before any form of investment.

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The bonding state between the carbon fiber and the polymer directly affects the properties of carbon fiber reinforced polymer composites (CFRP), which is influenced by the surface structural characteristics of carbon fiber (CF). The surface of CF is composed of tightly packed graphite crystallites lacking active carbon atoms, which results in low surface energy of CF and weak interfacial performance of CFRP. The interfacial properties can be evaluated indirectly through macro-mechanical properties, and can also be characterized by micromechanical testing methods. In order to improve the interfacial combination between the carbon fiber and the polymer, it is usually to modify the interface of CFRP, which mainly includes carbon fiber surface functionalization, carbon fiber surface coating and introduction of micro-nano enhancement phase. In this paper, researches on the interfacial properties of CFRP were reviewed, and the existing problems and the future research focus were also discussed.

Carbon fiber reinforced epoxy composites is playing a role in reducing structural weight and costs, saving resources and optimizing processes. However, the low properties of epoxy matrix and the weak interfacial bonding between carbon fiber and epoxy lead to the poor interlaminar performancec for carbon fiber or fabric reinforced epoxy composites. The application of nanomaterials is an effective way to improve or enhance the interlaminar properties of composite materials. Therefore, this paper summarized the research on the methods of nanomaterialsto reinforce resin matrix, and nanomaterials-carbon fibers multi-scale reinforcement to enhance the interlaminar performace, and nanomaterials to distribute the surface of prepreg uniformly, and nanomaterials to promote interfacial binding energy between carbon fiber and epoxy and nanomaterials macrostructure to improve the interlaminar properties of composites.