We present a novel technique for controlling oxygen fugacity, which is broadly used to in-situ measure the electrical conductivities in minerals and rocks during diamond anvil cell experiments. The electrical conductivities of olivine are determined under controlled oxygen fugacity conditions (Mo–MoO 2 ) at pressures up to 4.0 GPa and temperatures up to 873 K. The advantages of this new technique enable the measuring of the activation enthalpy, activation energy, and activation bulk volume in the Arrhenius relationship. This provides an improved understanding of the mechanism of conduction in olivine. Electrical conduction in olivine is best explained by small polaron movement, given the oxygen fugacity-dependent variations in conductivity.
In the face of increasingly severe climate change and its disastrous effects, how to effectively tackle it and reduce carbon dioxide emissions has become an important global issue. Clean development mechanism (CDM) project implementation provides an opportunity for more developing countries to actively participate in global climate governance. As the largest global emitter of carbon dioxide, have China’s CDM projects slowed down carbon dioxide emissions? In order to answer this question, the study constructs panel data at the provincial level from 2000 to 2017 to investigate the emission-reduction effects of China’s CDM projects. Results showed that China’s CDM projects’ implementation significantly reduced carbon dioxide emissions per unit of gross domestic product (GDP) and the growth rate of carbon dioxide emissions. The emission reduction effects of different types of CDM projects have obvious heterogeneity. In addition, this study further found that China’s CDM projects’ implementation can not only effectively substitute traditional fossil energy, but also improve energy-utilization efficiency.
The near-real-time legacy product of Tropical Rainfall Measuring Mission Multi-satellite Precipitation Analysis (3B42RT) and the equivalent products of Integrated Multi-satellite Retrievals for Global Precipitation Measurement mission (IMERG-E and IMERG-L) were evaluated and compared over Mainland China from 1 January 2015 to 31 December 2016 at the daily timescale, against rain gauge measurements. Results show that: (1) Both 3B42RT and IMERG products overestimate light rain (0.1–9.9 mm/day), while underestimate moderate rain (10.0–24.9 mm/day) to heavy rainstorm (≥250.0 mm/day), with an increase in mean (absolute) error and a decrease in relative mean absolute error (RMAE). The IMERG products perform better in estimating light rain to heavy rain (25.0–49.9 mm/day), and heavy rainstorm, while 3B42RT has smaller error magnitude in estimating light rainstorm (50.0–99.9 mm/day) and moderate rainstorm (100.0–249.9 mm/day). (2) Higher rainfall intensity associates with better detection. Threshold values are <2.0 mm/day, below which 3B42RT is unreliable at detecting rain; and <1.0 mm/day, below which both 3B42RT and IMERG products are more likely to cause false alarms. (3) Generally, both 3B42RT and IMERG products perform better in wet areas with relatively heavy rainfall intensity and/or during wet season than in dry areas with relatively light rainfall intensity and/or during dry season. Compared with 3B42RT, IMERG-E and IMERG-L constantly improve performance in space and time, but it is not obvious in dry areas and/or during dry season. The agreement between IMERG products and rain gauge measurements is low and even negative for different rainfall intensities, and the RMAE is still at a high level (>50%), indicating the IMERG products remain to be improved. This study will shed light on research and application during the transition in multi-satellite rainfall products from TMPA to IMERG and future algorithms improvement.