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Cool-season creeping bentgrass (Agrostis stolonifera) has the ability to form fine sports turf, but high temperatures result in summer bentgrass decline (SBD), especially in transitional and subtropical zones. Physiological responses in combination with the alteration in turf quality (TQ) will contribute to a better understanding of SBD in a subtropical zone. Field experiments were conducted from 2017 to 2019 to test the adaptability to summer stress among four cultivars (13M, Penncross, Seaside II, and PA-1). A constant ambient high temperature above 30 °C significantly decreased the TQ of the four cultivars during the summer months in 2017, 2018, and 2019. Significant declines in the chlorophyll content, photochemical efficiency of photosystem II (Fv/Fm and PIABS), leaf relative water content (RWC), and osmotic potential (OP) were induced by summer stress, whereas gradual increases in water-soluble carbohydrates, proline, hydrogen peroxide (H2O2), malondialdehyde (MDA), and electrolyte leakage (EL) were observed in the four cultivars during the summer months. The 13M and Penncross cultivars exhibited better performance than Seaside II and PA-1 in response to summer stress from 2017 to 2019, which is associated with better maintenance of photosynthesis, water status, WSC and proline accumulation, and cell membrane stability. The 13M and Penncross cultivars could be used as potential candidates for turf establishment in a subtropical zone. Physiological responses together with alterations in TQ also provided critical information for the breeding and development of germplasm with heat tolerance in creeping bentgrass species.

Two-dimensional (2D) layered materials hold great promise for electrochemical energy storage due to their unique structure. It is always desirable to explore new-type high-performance 2D structured electrode materials in energy field. In this work, layered transition-metal chalcogenophosphite is developed as the electrode material for supercapacitors for the first time. NiPS

This paper studies the fracture characteristics of wood in the longitudinal direction by combining KR curves and GR curve for fracture resistance ability analysis. Three-point-bending fracture test is carried out on the notched specimens. Digital image correlation (DIC) technique is applied to obtain the crack opening displacement and then calculate the equivalent crack length according to the double K fracture criterion. The KR and GR curves are constructed based on the experiment. The results show that the fracture toughness becomes larger but the fracture energy gets smaller with the increase of notch-to-depth ratio. Both the two curves show that the crack resistance ability is approximately improved when the notch-to-depth ratio increases. Through comparing KR and GR curves of the same specimen, it is seen that although these two kinds of fracture resistance curves have different evolution shapes, they both have three stages with the same dividing points, and they both can be used to analyze the quasi-brittle fracture process of wood.