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The Chronos 14Carbon-Cycle Facility is a new radiocarbon laboratory at the University of New South Wales, Australia. Built around an Ionplus 200 kV MIni-CArbon DAting System (MICADAS) Accelerator Mass Spectrometer (AMS) installed in October 2019, the facility was established to address major challenges in the Earth, Environmental and Archaeological sciences. Here we report an overview of the Chronos facility, the pretreatment methods currently employed (bones, carbonates, peat, pollen, charcoal, and wood) and results of radiocarbon and stable isotope measurements undertaken on a wide range of sample types. Measurements on international standards, known-age and blank samples demonstrate the facility is capable of measuring 14C samples from the Anthropocene back to nearly 50,000 years ago. Future work will focus on improving our understanding of the Earth system and managing resources in a future warmer world.

The Song of the Sea is long known to contain allusions to mythological motifs related to Canaanite religion that have been adapted to the faith of Israel. On the basis of a recent study of the Ugaritic texts KTU 1.107 and 1.100 it is shown that Exod 15:7-8 falls in this category of reinterpretation. It is proposed to render verse 7b ‘you sent your Ḥoron, he devoured them like stubble’. Suffixed personal pronouns with the names of deities are attested in Ugarit and ancient Hebrew inscriptions. However, in Exod 15 Ḥoron has been reduced to a redoutable assistant of God, an executioner called up to punish God’s opponents.

Poly(styrene‐co‐divinylbenzene) monolithic stationary phases with two different domain sizes were synthesized by a thermally initiated free‐radical copolymerization in capillary columns. The morphology was investigated at the meso‐ and macroscopic level using complementary physical characterization techniques aiming at better understanding the effect of column structure on separation performance. Varying the porogenic solvent ratio yielded materials with a mode pore size of 200 nm and 1.5 μm, respectively. Subsequently, nano‐liquid chromatography experiments were performed on 200 μm id × 200 mm columns using unretained markers, linking structure inhomogeneity to eddy dispersion. Although small‐domain‐size monoliths feature a relatively narrow macropore‐size distribution, their homogeneity is compromised by the presence of a small number of large macropores, which induces a significant eddy‐dispersion contribution to band broadening. The small‐domain size monolith also has a relatively steep mass‐transfer term, compared to a monolith containing larger globules and macropores. Structural inhomogeneity was also studied at the mesoscopic level using gas‐adsorption techniques combined with the non‐local‐density‐function‐theory. This model allows to accurately determine the mesopore properties in the dry state. The styrene‐based monolith with small domain size has a distinctive trimodal mesopore distribution with pores of 5, 15, and 25 nm, whereas the monolith with larger feature sizes only contains mesopores around 5 nm in size.

We investigate and discuss the proton conductivity properties of the cyanide-bridged metal–organic framework (MOF) [Nd(mpca)2Nd(H2O)6Mo(CN)8]·nH2O (where mpca is 5-methyl-2-pyrazinecarboxylate). This MOF is one of an exciting class of cyanide-bridged materials that can combine porosity with magnetism, luminescence, and proton conductivity. Specifically, we show that this material features highly hydrophilic open channels filled with water molecules. They enable a high proton conductivity, as much as 10−3 S cm−1. A rich hydrogen-bonding network, formed by the ligands' carboxylate groups with both coordinated and lattice water molecules, facilitates this high proton conductivity. Combined thermogravimetric studies, FTIR spectroscopy and PXRD analysis show that upon heating at 80 °C, the lattice water molecules are removed without any change in the framework. Further heating at 130 °C results in a partial removal of the coordinated water molecules, while still retaining the original framework. These activated MOFs shows an increasing conductivity from ∼10−9 S cm−1 to ∼10−3 S cm−1 when the relative humidity increases from 0% to 98%. Our studies show that the increase in proton conductivity is correlated with the re-hydration of the framework with lattice water molecules. The Arrhenius activation energy for the proton conductivity process is low (Ea = 37 kJ mol−1), indicating that the protons “hop” through the channels following the Grotthuss mechanism. The fact that this MOF is remarkably stable both under high humidity conditions and at relatively high temperatures (up to 130 °C) makes it a good candidate for real-life applications.

Dunes in the northern lowlands on planet Mars are composed of volcanic sands with high contents of volcanic glass and these deposits are mobilised and transported by winds in the present-day surface environment. In this experimental study we measured fluid thresholds for detachment of Mars-analogue volcanic glass particles using a low-fluid density wind tunnel under wind shear stresses in the range of 0.1–0.6 N m−2. Measured thresholds for larger particle diameters (>150 µm) were best-explained using a semi-empirical model of detachment which incorporates the effects of drag-induced rolling. Fitting of this semi-empirical model to obtained experimental data, combined with a residual analysis of the model fit with quantified particle properties made it possible to assess the sensitivity and validity of the model for predicting this type of particle detachment. This new model was used to predict the threshold shear stress for detachment of particles on Mars and indicated that larger particle diameters can detach by drag-induced rolling when subjected to present-day surface wind shears. A large morphological and granulometric variety of particles is therefore susceptible to this form of detachment, which provides a possible mechanism for the initial mobilisation of particles at lower wind speeds than required for detachment by saltation. Recent sand mobility may therefore have benefited from rolling as a contributing or as a saltation triggering process.

In Podzols, organic matter (OM) is stabilized mainly by interaction with minerals, as a direct consequence of pedogenic processes. Metal-organic associations strongly affect OM surface features, particularly microporosity. Cemented ortstein horizons (CM) may form during podzolization, accompanied by a spatial arrangement of OM on mineral surfaces, which differs from that in non-cemented horizons (N-CM). To investigate the metal-organic associations and their changes during pedogenesis, we selected both N-CM and CM podzolic horizons, isolated NaClO-resistant OM and compared the specific surface area (SSA) before and after OM oxidation. The SSA was assessed by using N-2, to detect the pores in the range of micropores (< 2 nm) and mesopores (2-50 nm), and CO2, to measure a smaller microporosity (< 0.5 nm), which is not accessible to N-2. Only the N-CM samples showed the typical increase in N-2-SSA after the removal of labile OM, while a decrease was found in all CM horizons. The CO2-SSA revealed a large number of small micropores characterizing OM, both before and after oxidation. The smallest micropore classes (< 0.5 nm) were, however, more abundant in NaClO-resistant OM, which had therefore a larger number of N-2-inaccessible surfaces than the labile pool. The N-2-SSA data thus indicated a more homogeneous coverage of mineral surfaces by stabilized OM in CM samples. Because of the abundance of small micropores, OM in these podzolic B horizons had extremely large CO2-SSA values (about 800 m(2) g(-1)), with sharp differences between the NaClO-labile OM (290-380 m(2) g(-1)) and the NaClO-stabilized pool (1380-1860 m(2) g(-1)), thus indicating very reactive illuvial organic materials.

We present a new metal-organic framework (MOF) built from lanthanum and pyrazine-2,5-dicarboxylate (pyzdc) ions. This MOF, [La(pyzdc)(1.5)(H2O)(2)]center dot 2H(2)O, is microporous, with 1D channels that easily accommodate water molecules. Its framework is highly robust to dehydration/hydration cycles. Unusually for a MOF, it also features a high hydrothermal stability. This makes it an ideal candidate for air drying as well as for separating water/alcohol mixtures. The ability of the activated MOF to adsorb water selectively was evaluated by means of thermogravimetric analysis, powder and single-crystal X-ray diffraction and adsorption studies, indicating a maximum uptake of 1.2 mmol g(-1) MOF. These results are in agreement with the microporous structure, which permits only water molecules to enter the channels (alcohols, including methanol, are simply too large). Transient breakthrough simulations using water/methanol mixtures confirm that such mixtures can be separated cleanly using this new MOF.

The exceptional hydrothermal- and solvent stability of organically linked silica makes it a promising candidate material for molecular separation membranes. Tailoring towards specific separation properties however requires precise control over the pore structure. Here we show that this can be achieved by adjusting the acid-to-Si ratio immediately before the onset of physical drying of the 1,2-bis(triethoxysilyl)ethane-based polymeric colloidal sols. This procedure provides uniform coating conditions and results in defect-free films. The structure development is investigated with in-situ Small-Angle X-ray Scattering, both in a solvent and during film drying. Acid-catalyzed colloidal growth in a solvent is governed by diffusion-limited cluster aggregation for all studied acid concentrations. Upon solvent evaporation, micropores (2 nm. The compressive forces are balanced by a network strengthened by ongoing condensation reactions, and by the positive charge on the hybrid organosilica. This results in a larger pore size under more acidic conditions. The permselectivity of the supported membranes correlates with the pore structure of the unsupported materials. Thus, the adaptability of the pore structure allows a wider applicability of organosilica membranes in energy-efficient industrial molecular separations.

The fabrication of nanoporous poly(vinylidene fluoride) (PVDF) and PVDF/nickel nanocomposites from semicrystalline block copolymer precursors is reported. Polystyrene-block-poly(vinylidene fluoride)-block-polystyrene (PS-b-PVDF-b-PS) is prepared through functional benzoyl peroxide initiated polymerization of VDF, followed by atom transfer radical polymerization (ATRP) of styrene. The crystallization of PVDF plays a dominant role in the formation of the block copolymer structure, resulting in a spherulitic superstructure with an internal crystalline-amorphous lamellar nanostructure. The block copolymer promotes the formation of the ferroelectric beta-polymorph of PVDF. Selective etching of the amorphous regions with nitric acid leads to nanoporous PVDF, which functions as a template for the generation of PVDF/Ni nanocomposites. The lamellar nanostructure and the beta-crystalline phase are conserved during the etching procedure and electroless nickel deposition.

Poly(styrene-co-divinylbenzene) monolithic stationary phases with two different domain sizes were synthesized by a thermally initiated free-radical copolymerization in capillary columns. The morphology was investigated at the meso- and macroscopic level using complementary physical characterization techniques aiming at better understanding the effect of column structure on separation performance. Varying the porogenic solvent ratio yielded materials with a mode pore size of 200 nm and 1.5 μm, respectively. Subsequently, nano-liquid chromatography experiments were performed on 200 μm id × 200 mm columns using unretained markers, linking structure inhomogeneity to eddy dispersion. Although small-domain-size monoliths feature a relatively narrow macropore-size distribution, their homogeneity is compromised by the presence of a small number of large macropores, which induces a significant eddy-dispersion contribution to band broadening. The small-domain size monolith also has a relatively steep mass-transfer term, compared to a monolith containing larger globules and macropores. Structural inhomogeneity was also studied at the mesoscopic level using gas-adsorption techniques combined with the non-local-density-function-theory. This model allows to accurately determine the mesopore properties in the dry state. The styrene-based monolith with small domain size has a distinctive trimodal mesopore distribution with pores of 5, 15, and 25 nm, whereas the monolith with larger feature sizes only contains mesopores around 5 nm in size.

Study of the unit delimitation in a number of ancient manuscripts lends extra support to the view that the speaker of the lament in Jer 4:19-21 is Lady Zion and that Jer 4:22 is a later addition.

In this study we present a global overview of the adsorption behavior of hexane isomers on MFI. With an experimental approach that couples a manometric technique with Near Infrared (NIR) spectroscopy, which has been recently developed, we did address adsorption kinetic properties of n-hexane, 2-methylpentane, 2,2-dimethylbutane and 2,3-dimethylbutane, and their binary mixtures. The adsorption equilibrium properties of the binary mixtures were also assessed using the same technique. Whereas the adsorption isotherms and heats of adsorption for single components have been studied by a manometric technique coupled with a micro calorimeter. The differential heats of adsorption of n-hexane increase slightly with loading, on the other hand the heat of adsorption of branched hexanes exhibits a decrease with loading. The diffusion rates on MFI of n-hexane, 2-methylpentane and 2,3-dimethylbutane are in the same order of magnitude. However, the diffusion rate of 2,2-dimethylbutane is two orders of magnitude lower than rates of the other isomers. In the binary mixtures the components interact and the difference between the diffusion rates of the components decreases. The MFI zeolite presents equilibrium selectivity towards the less branched isomers. In conclusion, a separation process for linear/mono-branched alkanes + double-branched alkanes, has to be based on its equilibrium properties and not based on adsorption kinetics.

Methylated microporous silica with high thermal stability and tuneable hydrophobicity was obtained by acid-catalysed sol–gel hydrolysis and condensation of mixtures of tetraethylorthosilicate (TEOS) and methyltriethoxysilane (MTES). The gels exhibited a trend towards smaller ultramicropores with increasing methyl content, while in addition some supermicropores were formed with sizes of around 2 nm. For low MTES concentration, dilution prior to gelation and ageing resulted in materials with clearly smaller ultramicropores, whereas only a minor effect of dilution on structure was found at high MTES concentration. The small ultramicropore size in ‘diluted’ materials can be associated with a higher extent of condensation of mainly TEOS monomers. Stable structures formed from MTES in an early stage of synthesis may explain the particular micropore structure of MTES-rich gels. With increasing methyl content and with dilution of the sol, the affinity of the surface to water was strongly decreased. The applicability of microporous silica in wet atmospheres may thus be improved by methylation, and their pore structure modified by adaptation of the recipe, which would be highly relevant for industrial gas and liquid separation by inorganic membranes.

Adsorption of n- and i-butane on zeolite MFI (silicalite type) at different temperatures has been investigated using a manometric technique combined with a micro-calorimeter. The Langmuir model can describe the isotherms for both components. The derived thermodynamic properties are in agreement with the literature data from other techniques. The differential heats of adsorption when plotted against loading present an initial plateau; followed by a slow rise, which can be attributed to adsorbate–adsorbate interactions. For i-butane these adsorbate–adsorbate interactions give rise to a sharp peak in heat of adsorption versus loading, at 0.6 mmol/g. A decrease at higher loadings on the heat of adsorption is observed for both isomers, this is attributed to surface adsorption.

γ-Al2O3 materials with small mesopores are hydrophobised by reactions with organochlorosilanes in liquid media. The structure of the modified materials is studied by means of physisorption and high-resolution SEM. A good measure of the decrease in surface polarity can be obtained from BET-fits of the N2 isotherms. It was found that many pores become blocked by using chlorosilanes with bulky organic groups, while a more open structure is preserved for methylchlorosilanes. Using toluene as a solvent leads to a higher extent of modification than ethanol, as observed for methylchlorosilanes. Multifunctional organochlorosilanes (i.e. with 2 or 3 Cl-groups) are more reactive but also give rise to blockage of some of the microporous part as a result of polymerisation reactions. Mono- and difunctional methylchlorosilanes give the best results for alumina materials with small mesopores, preserving an open structure and leading to homogeneous modification. Modification with methylchlorosilanes in toluene leads to the lowest surface polarity. The results give clues for optimising the procedures for hydrophobisation of porous materials with small mesopores.

Diffusivity data for alkanes in zeolites, as reported in the literature, may vary by orders of magnitude. A satisfactory answer as to the nature of these large differences has not been presented as...

Microporous properties of soil materials are considered important to the physical sequestration processes of contaminants and the influence on risk assessment for chemicals in the environment. We studied the microporous properties of five organic soil materials and two agricultural topsoils and thei