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In the context of China’s efforts to build world-class enterprises through mixed-ownership reform, this study aims to build an agency theory framework to analyze the differential relation between ownership structure and firm performance in majority versus minority state-owned enterprises (SOEs). It also evaluates the differential influence that political connectedness has on firm performance in the two types of SOEs.

Using a panel data set of Chinese state-controlled mixed-ownership enterprises covering the period 2010–2019, this paper uses ordinary least squares, random-effects, fixed-effects and three stage least squares regression analysis to study the differential impact of ownership structure and political connectedness on firm performance in majority versus minority SOEs.

In minority SOEs, firm performance is positively related to the ownership share of the largest private shareholder and state ownership positively moderates this relation. Furthermore, minority SOEs with a politically connected chairman perform worse than those with a politically connected chairman. In majority SOEs, there is no relation between the ownership share of the largest private shareholder and firm performance. In addition, majority SOEs with a politically connected chairman perform similar to those without a politically connected chairman.

The theoretical framework demonstrates that agency problems are substantially different in minority versus majority SOEs and that this influences how changes in ownership structure and in the type of chairman that is assigned affect firm performance. The empirical analysis confirms these predictions.

The pressure sensors can convert external pressure or mechanical deformation into electrical power and signal, which cannot only detect pressure or strain changes but also harvest energy as a self-powered sensor. This study aims to develop a self-powered flexible pressure sensor based on regular nanopatterned polymer films.

In this paper, the self-powered flexible pressure sensor is mainly composed of two nanopatterned polymer films and one conductive electrode layer between them, which is a sandwich structure. The regular nanostructures increase the film roughness and contact area to enhance the friction effect. To enhance the performance of the pressure sensor, different nanostructures on soft polymer sensitive layers are fabricated using UV nanoimprint lithography to generate more triboelectric charges.

Finally, the self-powered flexible pressure sensor is prepared, which consists of sub-200 nm resolution regular nanostructures on the surface of the elastic layer and an indium tin oxide electrode thin film. By converting the friction mechanical energy into electrical power, a maximum power of 423.8 mW/m2 and the sensitivity of 0.8 V/kPa at a frequency of 5 Hz are obtained, which proves the excellent sensing performance of the sensor.

The acquired electrical power and pressure signal by the sensor would be processed in the signal process circuit, which is capable of immediately and sustainably driving the highly integrated self-powered sensor system. Results of the experiments show that this new pressure sensor is a potential method for personal pressure monitoring, featured as being wearable, cost-effective, non-invasive and user-friendly.