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Ferrate (Fe(VI)) is usually effective for oxidizing a variety of organic pollutants within a few seconds, but some recalcitrant asorganophosphorus pesticides such as dimethoate require higher dose of Fe(VI) and inorganic phosphorus produced by mineralization is difficult to remove. In this study, acid-activated ferrate (Fe(VI)) was firstly used to degrade organophosphorus pesticides dimethoate and simultaneously remove total phosphorus (TP) from solution under simulated sunlight. At a Fe(VI):dimethoate molar radio of 15:1, dimethoate was almost completely removed within 20 min and 47% of TP in the solution was removed by the reduction product of Fe(VI) within 240 min. Electron paramagnetic resonance (EPR) and terephthalic acid (TA) fluorescence experiments showed that •OH radicals were continuously generated in the system, and •OH formation pathway was proposed. Importantly, the involvement of •OH in acid-activated Fe(VI) process was confirmed for the first time by EPR. In the acid-activated Fe(VI)/simulated sunlight system, the removal of dimethoate and TP gradually increased with the decrement of activation pH, whereas the increase of molar ratio of Fe(VI):dimethoate enhanced the removal of dimethoate and TP. The addition of inorganic anions (HCO3- and NO2-) had obvious inhibitory effects on dimethoate and TP removal. Eight degradation products including O,O,S-trimethylphosphorothiate, omethoate and 2-S-methyl-(N-methyl) acetamide were determined by gas chromatography mass spectrometry (GC-MS) analysis, and two possible degradation pathways were proposed. The insights gained from this study open a new avenue to simultaneously degrade and remove organic contaminants.

The single event effect (SEE) is an important consideration in electronic devices used in space environments because it can lead to spacecraft anomalies and failures. The linear energy transfer (LET) of ions is commonly investigated in studies of SEE. The use of a thin detector is an economical way of directly measuring the LET in space. An LET telescope consists of a thin detector as the front detector (D1), along with a back detector that indicates whether D1 was penetrated. The particle radiation effect monitor (PREM) introduced in this paper is designed to categorize the LET into four bins of 0.2–0.4, 0.4–1.0, 1.0–2.0 and 2.0–20 MeV·cm2/mg, and one integral bin of LET>20 MeV·cm2/mg. After calibration with heavy ions and Geant4 analysis, the LET boundaries of the first four bins are determined to be 0.236, 0.479, 1.196, 2.254, and 17.551 MeV·cm2/mg, whereas that of the integral bin is determined to be LET>14.790 MeV·cm2/mg. The acceptances are calculated by Geant4 analysis as 0.452, 0.451, 0.476, 0.446, and 1.334, respectively. The LET accuracy is shown to depend on the thickness of D1; as D1 is made thinner, the accuracy of the measured values increases.

This paper introduces the structure of the direct current power distribution system and the application of the wireless power distribution switch (WPDS), analyzes the operation mode of the WPDS, designs the wireless power transfer unit with high efficiency and the bi-directional communication unit in order to achieve wireless power switching and load current sensing in each channel at the same time. With the WPDS, bulky cables and switches can be saved and the problem of electric sparks is eliminated, reducing weight of the power distribution system and improving the lifetime of the power distribution switches.

The Wireless Power Transfer (WPT) technology is a promising way to break the limit of capability and operation for satellites and make the satellites much lighter, smaller and more flexible and durable. This paper introduces the system integration techniques of WPT between satellites including the energy control subsystem, the laser-WPT subsystem and the microwave-WPT subsystem, and discusses the mechanisms of laser WPT subsystem and the ground demonstration platform of the microwave-WPT subsystem. Finally, this paper gives the experimental results of the WPT on the ground.