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The dynamic spalling characteristics of rock are important for stability analysis in rock engineering. This paper presented an experimental investigation on the dynamic spalling characteristics of granite with different temperatures and strain rates. A series of dynamic spalling tests with different impact velocities were conducted on thermally treated granite at different temperatures. The dynamic spalling strengths of granite with different temperatures and strain rates were determined. A model was proposed to correlate the dynamic spalling strength of granite, high temperature and strain rate. The results show that the spalling strength of granite decreases with increasing temperature. Moreover, the spalling strength of granite with a higher strain rate is larger than that with a lower strain rate. The proposed model can describe the relationship among dynamic spalling strength of granite, high temperature and strain rate.

Experiments conducted on the J-TEXT tokamak have provided the first evidence that the Beta-induced Alfvén Eigenmode (BAE) is localized inside the isolated helical flux tube of its edge m / n = 3/1 magnetic island. The observations show that the BAE forms a standing wave inside the magnetic island, with its nodes located at the X- and O-points of the magnetic island. When the island is cut open by contact with the limiter plates, the BAE is found to remain inside the remnant closed island in the Scrape-Off Layer, but its amplitude decreases as the width of the remnant island becomes smaller.

On the J-TEXT tokamak, the dynamics of edge magnetic topology during the opening of the edge magnetic islands induced by the external Resonant Magnetic Perturbation (RMP) are investigated. The edge island chain is pushed outward by increasing plasma toroidal current to intersect the poloidally and toroidally localized divertor plate, forming an open magnetic island in the Scrape-Off Layer (SOL). The location of the strike points on the divertor plate predicted by the HINT code is in agreement with the experimental observations. The influence of the magnetic topology on edge plasma profiles has also been investigated using Langmuir probes. The properties of edge ${T_{\text{e}}}$ , ${n_{\text{e}}}$ , ${P_{\text{e}}}$ and ${E_{\text{r}}}$ profiles are studied as function of three magnetic structures in ${q_{\text{a}}}$ -dependence experiments and two magnetic structures in RMP configuration-dependence experiments. Some common features are observed. Inside the edge closed and SOL remnant islands, flat ${P_{\text{e}}}$ but non-flat ${T_{\text{e}}}$ and ${n_{\text{e}}}$ profiles are detected. When transitioning from the edge closed island to the partially open island with remnant island, the local flat ${P_{\text{e}}}$ profile is shifted outward accompanied by a narrower flattened ${P_{\text{e}}}$ region. The steep slopes of ${T_{\text{e}}}$ , ${n_{\text{e}}}$ and ${P_{\text{e}}}$ are measured in the SOL regions characterized by a long connection length ${L_{\text{c}}}$ , and the longer ${L_{\text{c}}}$ , the steeper slopes. ${E_{\text{r}}}$ exhibits a negative well inside the remnant island with infinite ${L_{\text{c}}}$ and in the SOL regions where ${L_{\text{c}}}$ significantly exceeds than the electron mean free path ${\lambda _{\text{e}}}$ , but develops a positive value in the SOL regions where ${L_{\text{c}}}$ is relatively short.

Photosynthesis is sensitive to water deficit (WD) stress. Maize (Zea mays L.) yield is vulnerable to water stress, especially if it occurs during the reproductive stage. In this study, the expression patterns of photosynthesis-related genes, together with photosynthetic gas-exchange and fluorescence parameters were investigated in a maize inbred line exposed to 50% of field water capacity (moderate WD) for 15 d after tassel emergence. The results demonstrated that WD down-regulated expression of psbA, psbB, psbC, psbP, psaA, psaB, and cab, especially at later periods of WD stress. Besides, with the increased WD stress, the steady decline in the value of photosynthesis performance index, maximum quantum yield of primary photochemistry, quantum yield for electron transport, quantum yield for the reduction of end acceptors of PSI per photon absorbed, and the efficiency of an electron beyond QA- that reduced PSI acceptors, and a clear increase in the J-step and I-step, K-band as well as L-band were observed. The results suggested that WD might restrict light-harvesting and electron transport. Interestingly, leaf transcript levels of rbcL and rbcS were up-regulated at the later stage of water stress in maize inbred line, which helped repair injury to PSII centers and maintain PSII activity (increased quantum yield of dissipation and effective antenna size of an active reaction center) under 15-d lasting WD.