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It has been shown that leadership is a major factor that influences creative performance. Although past studies have found that leader-member exchange (LMX) has direct effects on employee creative performance, there continues to be a lack of research examining how the LMX relationship mediates creative performance. This study used self-determination theory to examine the mediating effects of the LMX relationship on creative performance through attitudinal and emotional processes. Participants were supervisors and subordinates of township enterprises in the Pearl River Delta in China. There were 386 valid supervisor-subordinate dyads. Supervisors were responsible for assessing creative performance and the remaining variables were completed by employees. Results showed that high LMX increased the positive moods of subordinates, improved creative performance, and stimulated intrinsic motivation for improvement. Based on the results, we have proposed academic and practical recommendations such as organizations that want to encourage creativity, could begin by training managers to demonstrate high LMX by strengthening their relationships with employees. We also described study limitations, and suggested directions for future studies.

The tribological properties of lubricating oil containing micro/nanoscale WS 2 (90 nm, 2 mm) and ionic liquid [C 7 H 11 F 3 N 2 O 3 S] are evaluated using a four-ball friction tester. Results show that the addition of micro/nano-scale WS 2 can improve the tribological properties of the base oil; moreover, adding the ionic liquid as a solvent may lead to a better mixing of the micro/nano-scale WS 2 and base oil and promote the dispersion of WS 2 in the sample oil. The base oil with 90 nm nano-WS 2 and ionic liquid presents the best anti-friction and anti-wear properties at 1 wt.% content. The surface analysis of wear scars reveals that ploughing is the main cause of wear in the three bottom balls. Furthermore, the wear furrows of nano-WS 2 as lubricating additive are uniform and symmetrical and can homogenously appear on the friction area. This work proves that the micro/nano-scale WS 2 plays an important role in improving the performance of tribological properties of lubricating oil.

In the present work, the relationship curve of the coefficient of friction (COF) with varying loads of different morphology WS2 lubricating additives in the friction process at various sliding speeds was studied. On this basis, wear marks and elements on the wear surfaces after friction were analyzed, and then the anti-wear and mechanism effects of WS2 of different forms in the lubrication process were discussed. Meanwhile, the Stribeck curve was used to study the lubrication state of the lubricating oil in the friction process. It was revealed that the COF of lubricating oil containing lamellar WS2 decreased by 29.35% at optimum condition and the minimum COF was concentrated at around 100 N. The COF of lubricating oil containing spherical WS2 decreased by 30.24% and the minimum coefficient was concentrated at 120 N. The extreme pressure property of spherical WS2 was better than that of lamellar WS2, and the wear resistance of spherical WS2 was more stable when the load was over 80 N. The different morphology of WS2 additives can play anti-wear and anti-friction roles within a wide range of sliding speeds.