SignificanceIn this study we report the discovery of a previously unrecognized chemical class, dihydroxymagnesium carboxylates, [(HO)2MgO2CR]−, gained from nonterrestrial meteoritic analyses. The existence of such low-coordination organomagnesium anionic compounds expands our knowledge and understanding of extreme environments from which the early solar system emerged and has evolved. The appearance this CHOMg chemical class extends the previously investigated vast diversity of CHNOS groups in meteoritic soluble organics. Experimental evidence is given for the connection between the evolution of organic compounds and minerals. These thermostable compounds might have contributed to the stabilization of organic molecules on a geological time scale, which emphasizes their potential astrobiological relevance.

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Libyan Desert Glass (LDG) is a SiO 2 -rich natural glass whose origin, formation mechanism, and target material are highly debated. We here report on the finding of a lensshaped whitish inclusion within LDG. The object is dominantly composed of siliceous glass and separated from the surrounding LDG by numerous cristobalite grains. Within cristobalite, several regions rich in mullite often associated with ilmenite were detected. Mineral assemblage, chemical composition, and grain morphologies suggest that mullite was formed by thermal decomposition of kaolinitic clay at atmospheric pressure and T ≥ 1600°C and also attested to high cooling rates under nonequilibrium conditions. Cristobalite contains concentric and irregular internal cracks and is intensely twinned, indicating that first crystallized b-cristobalite inverted to a-cristobalite during cooling of the SiO 2 -rich melt. The accompanied volume reduction of 4% induced the high density of defects. The whitish inclusion also contains several partly molten rutile grains evidencing that at least locally the LDG melt was at T ≥ 1800°C. Based on these observations, it is concluded that LDG was formed by high-temperature melting of kaolinitic clay-, rutile-, and ilmenite-bearing Cenozoic sandstone or sand very likely during an asteroid or comet impact onto Earth. While melting and ejection occurred at high pressures, the melt solidified quickly at atmospheric pressure.

Recently, many different plasma sources are being investigated for exhaust gases treatment, odor abatement, VOC removal, soil conditioning, surface decontamination or tissue disinfection and sterilization. Among many different plasma reactors investigated in laboratories, gliding arc discharges (GAD), dielectric barrier discharges (DBD), pulsed discharges (PD), atmospheric pressure glow discharges (APGD) and atmospheric pressure plasma jets (APPJ) seem to be the most promising for high pressure low temperature applications. They can be designed as multi-electrodes’ high power system that can be used in environment protection processes, like decontamination of large surfaces and treatment of large volume of polluted gases, as well as small size and low power devices for biomedical applications, like plasma healing, disinfection and sterilization. Paper presents review of power supply systems for cold plasma reactors. Dielectric Barrier Discharge (DBD), Gliding Arc Discharge (GAD) and atmospheric pressure plasma jet (APPJ) reactors with their supply systems have been discussed from the point view of their characteristics, possibility to control power to the discharge and efficiency. Taking into account the plasma reactor characteristics and nature (nonlinear resistive and/or capacitive) different solutions of power suppliers have been presented: transformer type, AC/DC/AC inverter, RF-frequency system and frequency resonant inverter.

Ultraviolet radiation in the C band to limit storage losses of potato was applied. Six edible potato varieties, viz., Lord, Vineta, Owacja, Ditta, Finezja and Tajfun were used as test materials. UV-C radiation was emitted from a 15 W radiator. The wavelength of the light used to irradiate potato tubers was 253,7 nm and the power density from 80 to 100 μW/cm2. The method of reduction of storage losses of potato tubers, based on their exposure to UV-C irradiation, can complement the presently used methods of potato crop protection during long-term storage.