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This paper presents a proof-of-concept study establishing effectiveness of the Active Plasma Sterilizer (APS) for sterilization in planetary protection. The APS uses Compact Portable Plasma Reactors (CPPRs) to produce surface dielectric barrier discharge, a type of cold plasma, using ambient air to generate and distribute reactive species like ozone used for decontamination. Sterilization tests were performed with pathogenic bacteria (Escherichia coli and Bacillus subtilis) on materials (Aluminum, Polycarbonate, Kevlar and Orthofabric) relevant to space missions. Results show that the APS can achieve 4 to 5 log reductions of pathogenic bacteria on four selected materials, simultaneously at 11 points within 30 minutes, using power of 13.2 +/- 2.22 W. Spatial sterilization data shows the APS can uniformly sterilize several areas of a contaminated surface within 30 minutes. Ozone penetration through Kevlar and Orthofabric layers was achieved using the CPPR with no external agent assisting penetration. Preliminary material compatibility tests with SEM analysis of the APS exposed materials showed no significant material damage. Thus, this study shows the potential of the APS as a lightweight sustainable sterilization technology for planetary protection with advantages of uniform spatial decontamination, low processing temperatures, low exposure times, material compatibility and the ability to disinfect porous surfaces.

This paper attempts to establish the driver-driven relationship, co-integration, and causality relation between the Shariah indices of India and Indonesia. For this reason, two Indian Shariah indices, Nifty 500 and S&P BSE 500 Shariah and two Indonesian Shariah indices IDX Shariah and Jakarta Islamic Index (JII) have been taken into consideration. A total of 1585 data points have been taken into account, and the period of the study is from May 2013 to October 2019 (approximately six years and six months). Empirical evidence of the study proves that there is reciprocity among the Shariah index of India, Nifty 500 Shariah, and S&P BSE 500 Shariah. There exists no relationship between IDX Shariah and Jakarta Islamic Index when compared with Nifty 500 Shariah, individually. IDX Shariah is a driver index, though it is 11 years younger than Jakarta Islamic Index and, which is the driven index.

Plasma actuators have been extensively studied for flow control applications over the past two and a half decades. While these studies have been traditionally focused on characterizing their performances as flow control devices, the performance of plasma actuators under adverse conditions such as dew or light rain remains to be less explored. This paper seeks to study the effects of water adhesion from droplets directly sprayed on to a plasma actuator using thrust recovery as the performance metric. It was found in all tests that wet actuators quickly recover plasma glow, before gradually regaining performance comparable to the dry actuator. The measured thrust for the wet actuator after 5 s of operation recovered by 46% and 42% of the thrust of the dry actuator for 50.0–62.5 g m−2 and 125–150 g m−2 of sprayed water droplets, respectively. At 22.5 kVpp and 14 kHz, the highest thrust recovery was recorded at 84% of that of the dry actuator after 80 s of operation. For 17.5 kVpp and 14 kHz the wet thrust recovered by 79%, while for 22.5 kVpp and 10 kHz the wet thrust recovered by 68% of their dry counterpart in 80 s. For 17.5 kVpp and 14 kHz, the thrust almost fully recovered in comparison to the dry actuator after about 290 s of operation. These results indicate that both applied voltage and operating frequency plays a critical role in the performance recovery while the latter may have a stronger influence. Performance recovery for a wet serpentine shaped plasma actuator is also included for general applicability. The power data in all cases show that wet actuators consume more power which with time gradually approach the dry actuator power data. This is because during the initial stages of operation, the rolling mean current of the wet actuator is higher than the dry actuator even though the ionization spikes of dry actuator is stronger.