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Pore fluid is ubiquitous within the Earth's crust and severely impacts shear rupture propagation and the slip behaviors of faults. We conducted triaxial experiments on sandstone to investigate the effects of crack damage, confining pressure, and water on fault slip behaviors and rupture propagation. Two loading configurations, conventional loading and increasing-amplitude cyclic loading, were conducted to compare the inelastic behavior and failure modes of sandstone samples. In addition to a macroscopic deformation and mechanical properties analysis, a noncontact optical scanner and magnetic resonance imaging technique were used to analyze the microstructural evolution of the sandstone. The results show that a higher confining pressure results in a more homogeneous fault plane. Fault slip behaviors can be divided into the slip-strengthening and slip-weakening stages. In the brittle regime, pore water reduces the brittle strength of rocks but does not induce different fault slip behaviors. When the confinement is high enough, rocks fail in the brittle–ductile transition regime where dynamic faulting is prohibited. In the brittle–ductile transitional regime, pore water enhances stabilization, and the slip behaviors distinctively differ from those occurring without water. [ABSTRACT FROM AUTHOR]

Slurry casting has been used to fabricate lithium‐ion battery electrodes for decades, which involves toxic and expensive organic solvents followed by high‐cost vacuum drying and electrode calendaring. This work presents a new manufacturing method using a nonthermal plasma to create inter‐particle binding without using any polymeric binding materials, enabling solvent‐free manufacturing electrodes with any electrochemistry of choice. The cold‐plasma‐coating technique enables fabricating electrodes with thickness (>200 μm), high mass loading (>30 mg cm−2), high peel strength, and the ability to print lithium‐ion batteries in an arbitrary geometry. This crosscutting, chemistry agnostic, platform technology would increase energy density, eliminate the use of solvents, vacuum drying, and calendaring processes during production, and reduce manufacturing cost for current and future cell designs. Here, lithium iron phosphate and lithium cobalt oxide were used as examples to demonstrate the efficacy of the cold‐plasma‐coating technique. It is found that the mechanical peel strength of cold‐plasma‐coating‐manufactured lithium iron phosphate is over an order of magnitude higher than that of slurry‐casted lithium iron phosphate electrodes. Full cells assembled with a graphite anode and the cold‐plasma‐coating‐lithium iron phosphate cathode offer highly reversible cycling performance with a capacity retention of 81.6% over 500 cycles. For the highly conductive cathode material lithium cobalt oxide, an areal capacity of 4.2 mAh cm−2 at 0.2 C is attained. We anticipate that this new, highly scalable manufacturing technique will redefine global lithium‐ion battery manufacturing providing significantly reduced plant footprints and material costs. [ABSTRACT FROM AUTHOR]

Objectives. This study assessed the occupational health risks of work group exposure to trichloroethylene (TCE) in the electroplating and electronics industries in China. Methods. The UK Control of Substances Hazardous to Health (COSHH) Essential, the US Environmental Protection Agency (EPA) and the Singapore and the Chinese semiquantitative risk assessment models were used to assess the risks of TCE. Twenty degreasing groups and 14 cleaning groups were recruited in the companies selected. Results. The concentrations of TCE in 66.7% of the cleaning groups and 35.0% of the degreasing groups exceeded the permissible concentration time-weighted average (PC-TWA) in China, and the concentrations of TCE in 100.0% of the cleaning groups and 70.0% of the degreasing groups exceeded the permissible concentration short-term exposure limit (PC-STEL) in China. Over 60.0% of the work groups were evaluated at high risk and over half of the work groups were evaluated at high cancer risk by the risk assessment models. Conclusion. Most work groups exposed to TCE in the electroplating and electronics industries in China are at high risk. The cleaning groups may have a higher risk for TCE exposure. The Chinese exposure index method and the synthesis index method are more practical than the other methods. [ABSTRACT FROM AUTHOR]

In order to explore the influence of reservoirs regulation in the upper basin of Xiluodu Reservoir, 11 key reservoirs in the upper reaches of Xiluodu Reservoir are studied. Based on the analysis of its overall regulation performance, the data of upstream reservoir group from 2006 to 2016 is used to analyze the impact of the upstream reservoir group. By dividing scheduling period of Xiluodu Reservoir into different stages, the impact of each stage and the proportion of impacts of each river basin is analyzed, the degree of impact of each basin is clarified. The results reveals that the upstream reservoir group storage accounts for about 20% of the inflow of Xiluodu Reservoir, which can contribute to the actual dispatching work of Xiluodu Reservoir.

The main tributaries of the upper reaches of the Yangtze River are not only the strategic base for China’s water resources, but also an important hydropower base for the “West-East Power Transmission Strategy”. With the completion of these reservoir groups, a large-scale mixed reservoir system across the different basins has been formed, which makes the requirements for joint optimization and scheduling of large-scale hydropower system getting higher and higher. This paper focuses on the key problems faced by the joint optimization of large-scale hydropower system in the basin. Taking the Yalong River and the middle and downstream of the Jinsha River as the research area, the hybrid optimization method is introduced herein to solve the joint optimal scheduling model. The results reveal that the power generation by joint optimal scheduling is much more than separately scheduling, and the total power generation increased by 2.84% on average. As Mid-Jinsha cascade and Yalong River cascade has a 690 million kW·h and 190 million kW·h decrease in power generation respectively, the downstream Jinsha River cascade has a power generation increase of 4.31 billion kW·h.