The smallest space miners: principles of space biomining

As we aim to expand human presence in space, we need to find viable approaches to achieve independence from terrestrial resources. Space biomining of the Moon, Mars and asteroids has been indicated as one of the promising approaches to achieve in-situ resource utilization by the main space agencies. Structural and expensive metals, essential mineral nutrients, water, oxygen and volatiles could be potentially extracted from extraterrestrial regolith and rocks using microbial-based biotechnologies. The use of bioleaching microorganisms could also be applied to space bioremediation, recycling of waste and to reinforce regenerative life support systems. However, the science around space biomining is still young. Relevant differences between terrestrial and extraterrestrial conditions exist, including the rock types and ores available for mining, and a direct application of established terrestrial biomining techniques may not be a possibility. It is, therefore, necessary to invest in terrestrial and space-based research of specific methods for space applications to learn the effects of space conditions on biomining and bioremediation, expand our knowledge on organotrophic and community-based bioleaching mechanisms, as well as on anaerobic biomining, and investigate the use of synthetic biology to overcome limitations posed by the space environments.

Organic Spacer Engineering in 2D/3D Hybrid Perovskites for Efficient and Stable Solar Cells

Perovskite solar cells (PSCs) have attracted widespread attention as their adjustable band gap, easy manufacture, and longer carrier diffusion length. However, the influence of environmental factors such as water, oxygen,...

Commercial exploitation of Kуiv reservoir as a fishery water body (a review)

Purpose. To analyze an array of special scientific literature and summarize the obtained information on the commercial exploitation of the Kуiv reservoir as a fishery water body. To review main abiotic conditions of the reservoir, which exist and form the specificity of its commercial use by the fishery industry of Ukraine. To highlight the historical course of their impact on the fish fauna of the Kyiv Reservoir and general forecasts for its future transformations. Findings. An overview of scientific publications devoted to the specifics of commercial exploitation of the Kуiv reservoir as a fishery water body from the moment of its creation to the present day were presented. In particular, following was analyzed: hydrological regime, color and chemical composition of water, oxygen regime, accumulation of heavy metals, formation of bottom sediments and landscape. In addition, the radioecological situation in the reservoir was anazyed, both general and in three most significant areas for fisheries — in bottom sediments, macrophytes, and fish fauna. The literature data on the specificity of the above-mentioned abiotic factors in this reservoir, which form the hydro-ecological feature of this reservoir, were generalized. The main directions of their influence on the ichthyofauna of the Kуiv reservoir, which affect the possibility of its commercial exploitation, were described. The share of anthropogenic origin in the composition of the above-mentioned abiotic factors and the consequences of its impact were highlighted. The perspective ways of further development of the Kiev reservoir as a fishery water body of strategic importance for Ukraine were shown. Practical Value. The review may be useful for scientists, PhD students, students, government authorities, and private entrepreneurs involved in research process or exploatation of aquatic living resources in internal water bodies, primarily in the Kуiv reservoir. Keywords: Kуiv reservoir, fishery water body, hydrological regime, water chemical composition, water oxygen regime, heavy metals, bottom sediments, landscape formation, radioecological situation.

Novel Coordination Mode in the Potassium Mefenamate Trihydrate Polymeric Structure

As a result of the synthesis of mefenamic acid with potassium hydroxide, a salt with a polymeric structure is formed. The one-dimensional polymeric structure was studied by single crystal X-ray diffraction. The potassium cation is coordinated to one oxygen atom of the carboxylate group and six water oxygen atoms. Potassium ions are bridged by oxygen atoms of water molecules. The crystal structure was used as an input to QTAIM and NCI approaches to investigate the K-O interactions linking the cation with the water oxygen and carboxylate groups. The weak K-O interactions of the potassium cation and water oxygen atoms were strong enough to form a polymeric structure. The flexibility of the weak interactions is responsible for a novel coordination mode in the potassium mefenamate trihydrate.

Intermediate- and Deep-Water Oxygenation History in the Subarctic North Pacific During the Last Deglacial Period

Deglacial dissolved oxygen concentrations were semiquantitatively estimated for intermediate and deep waters in the western Bering Sea using the benthic foraminiferal-based transfer function developed by Tetard et al. (2017), Tetard et al. (2021a). Benthic foraminiferal assemblages were analyzed from two sediment cores, SO201-2-85KL (963 m below sea level (mbsl), the intermediate-water core) and SO201-2-77KL (2,163 mbsl, the deep-water core), collected from the Shirshov Ridge in the western Bering Sea. Intermediate waters were characterized by an oxygen content of ∼2.0 ml L−1 or more during the Last Glacial Maximum (LGM)–Heinrich 1 (H1), around 0.15 ml L−1 during the middle Bølling/Allerød (B/A)–Early Holocene (EH), and a slight increase in [O2] (∼0.20 ml L−1) at the beginning of the Younger Dryas (YD) mbsl. Deep-water oxygen concentrations ranged from 0.9 to 2.5 ml L−1 during the LGM–H1, hovered around 0.08 ml L−1 at the onset of B/A, and were within the 0.30–0.85 ml L−1 range from the middle B/A to the first half of YD and the 1.0–1.7 ml L−1 range from the middle to late Holocene. The [O2] variations remind the δ18O NGRIP record thereby providing evidence for a link between the Bering Sea oxygenation at intermediate depths and the deglacial North Atlantic climate. Changes in the deep-water oxygen concentrations mostly resemble the deglacial dynamics of the Southern Ocean upwelling intensity which is supposed to be closely coupled with the Antarctic climate variability. This coherence suggests that deglacial deep-water [O2] variations were primarily controlled by changes in the circulation of southern-sourced waters. Nevertheless, the signal from the south at the deeper site might be amplified by the Northern Hemisphere climate warming via an increase in sea-surface bioproductivity during the B/A and EH. A semi-enclosed position of the Bering Sea and sea-level oscillations might significantly contribute to the magnitude of oxygenation changes in the study area during the last deglaciation. Interregional correlation of different proxy data from a wide range of water depths indicates that deglacial oxygenation changes were more pronounced in the Bering and Okhotsk marginal seas than along the open-ocean continental margin and abyssal settings of the North Pacific.

Crystal structure of bis[cis-diaquabis(phenanthroline)cobalt(II)] bis(citrato)germanate(IV) dinitrate

The asymmetric unit of the title compound, [Co(C12H8N2)2(H2O)2]2[Ge(C6H5O7)2](NO3)2, features two complex [(C12H8N2)2(H2O)2Co]2+ cations, two NO3 − anions as well as one centrosymmetric [(C6H5O7)2Ge]2− anion. Two HCit ligands (Cit = citrate, C6H4O7) each coordinate via three different oxygen atoms (hydroxylate, α-carboxylate, β-carboxylate) to the Ge atom, forming a slightly distorted octahedron. The coordination polyhedron of the Co atom is also octahedral, formed by coordination of four nitrogen atoms from two phenanthroline molecules and two water oxygen atoms. In the crystal, the cations and anions are linked by hydrogen bonds and form layers parallel to the bc plane. The structure exhibits disorder of the NO3 − anion [disorder ratio 0.688 (9) to 0.312 (9)]. There are also highly disordered solvent molecules (presumably water and/or ethanol) in the crystal structure; explicit refinement of these molecules was not possible, and the content of the voids was instead taken into account using reverse Fourier transform methods [SQUEEZE procedure in PLATON; Spek (2015). Acta Cryst. C71, 9–18]. The given chemical formula and other crystal data do not take into account the unknown solvent molecule(s).