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Two series of bimetallic photocatalysts (0.5% Pt/0.01–0.5% IrOx/g-C3N4 and 0.1% Pt/0.01–0.1% IrOx/g-C3N4) were synthesized by the thermolysis of melamine cyanurate and a successive deposition of platinum and iridium labile complexes (Me4N)2[Pt2(μ-OH)2(NO3)8] and fac-[Ir(H2O)3(NO2)3. The synthesized photocatalysts were studied by a set of physicochemical analysis techniques. Platinum exists in two states, with up to 60% in metallic form and the rest in the Pt2+ state, while iridium is primarily oxidized to the Ir3+ state, which was determined by X-ray photoelectron spectroscopy (XPS). The specific surface area (SBET), which is determined by low-temperature nitrogen adsorption, ranges from 80 to 100 m2 g−1 and the band gap energy (Eg) value is in the range of 2.75–2.80 eV as found by diffuse reflectance spectroscopy (DRS). The activity of the photocatalysts was tested in the photocatalytic production of hydrogen from ultrapure water under visible light (λ = 400 nm). It was found that the splitting of water occurs with the formation of the stochiometric amount of H2O2 as an oxidation product. Two photocatalysts 0.5% Pt/0.01% IrOx/g-C3N4 and 0.1% Pt/0.01% IrOx/g-C3N4 showed the highest activity at 100 μmol h−1 gcat−1, which is among the highest in H2 production published for such systems. [ABSTRACT FROM AUTHOR]

Extensive work on a Cu-modified TiO2 photocatalyst for CO2 reduction under visible light irradiation was conducted. The structure of the copper cocatalyst was established using UV–vis diffuse reflectance spectroscopy, high-resolution transmission electron microscopy, X-ray absorption spectroscopy, and X-ray photoelectron spectroscopy. It was found that copper exists in different states (Cu0, Cu+, and Cu2+), the content of which depends on the TiO2 calcination temperature and copper loading. The optimum composition of the cocatalyst has a photocatalyst based on TiO2 calcined at 700 °C and modified with 5 wt% copper, the activity of which is 22 µmol/(h·gcat) (409 nm). Analysis of the photocatalysts after the photocatalytic reaction disclosed that the copper metal on the surface of the calcined TiO2 was gradually converted into Cu2O during the photocatalytic reaction. Meanwhile, the metallic copper on the surface of the noncalcined TiO2 did not undergo any transformation during the reaction. [ABSTRACT FROM AUTHOR]

As many native women in conquest accounts (historical and fictional), Rahab in Joshua 2 is often “hypersexualised” in biblical scholarship. One narrative detail gratuitously read in sexual terms is her name, Rahab, which is linked to the idea of “broadness.” Traditionally, “Rahab” is read as a harsh nickname highlighting the woman’s occupation, prostitution, or as a reference to her genitals. Against these readings, this discussion considers the language of “broadness” in biblical profiles of the Promised Land and the Torah, key motifs from Joshua 1–2, and demonstrates that the trope of “broadness/spaciousness” constitutes the rhetoric of liberation in the Hebrew Bible. That is, God is often cast as someone who brings afflicted/landless people to a broad locale or “broadens/enlarges” their hearts through his Torah. Since Rahab is linguistically and thematically linked to these acts, it is argued that through her Joshua 2 offers a midrash on Joshua 1. That is, from within Canaan, her name reverberates God’s earlier promises to Israel (“he [God] has created a wide expanse”) and she, herself, models a life informed by the Torah (vv. 9–12). Arguably, through her, Joshua 2 also offers a microcosm of YHWH’s own nature and modus operandi in the world.

Regarding the creation account in Genesis 2–3, D.M. Carr observes that this text freely repurposes prior cosmological traditions, and so it is a case of a 'fluid adaptation of its Near Eastern precursors...' (Carr, [2020], 52–53). Building on his discussion, this article analyzes an ANE motif that has not been linked to Genesis 2–3 yet, i.e., the formation of humanity from divine tears or in the wake of divine laments. Known in various configurations from Egyptian, Mesopotamian, and Greek sources, this motif includes tears of a god or gods either as a generative substance in the making of humans or as a driving force for their origins. In light of these traditions, this article considers the pronouncement 'It is not good for the human to be alone' (Gen. 2:18), arguing that it is a variation on the 'divine tears' myth. As such, this pronouncement addresses a multi-faceted form of 'aloneness' in the emerging cosmos. [ABSTRACT FROM AUTHOR]

Space agencies have recognized the risks of astronauts’ exposure to space radiation and are developing complex model-based risk mitigation strategies. In the foundation of these models, there are still significant gaps of knowledge concerning nuclear fragmentation reactions which need to be addressed by ground-based experiments. There is a lack of data on neutron and light ion production by heavy ions, which are an important component of galactic cosmic radiation (GCR). A research collaboration has been set up to characterize the secondary radiation field produced by GCR-like radiation provided by a particle accelerator in thick shielding. The aim is to develop a novel method for producing high-quality experimental data on neutron and light ion production in shielding materials relevant for space radiation protection. Four complementary detector systems are used to determine the energy and angular distributions of high-energy secondary neutrons and light ions. In addition to the physical measurement approach, the biological effectiveness of the secondary radiation field is determined by measuring chromosome aberrations in human peripheral lymphocytes placed behind the shielding. The experiments are performed at the heavy ion