Two new salts of a mononuclear tripodal Fe(II) complex were prepared, using ClO and Cl. The ClO sample (1) remained HS at low temperatures, similar to the previously reported BF analogue. Crystallising with the Cl anion (2) led to a markedly different crystal packing arrangement, and engendered SCO activity.
View Article and Find Full Text PDFDuloxetine hydro-chloride (trade name Cymbalta) is marketed as a single enanti-omer ()--methyl-3-(naphthalen-1-yl-oxy)-3-(thio-phen-2-yl)propyl-am-in-ium chloride, CHNOS·Cl, which is twice as effective as the ()-enanti-omer in serotonin uptake. Here, we report the crystal structure of duloxetine hydro-chloride in its racemic form (space group 2), where it shows significant differences in the mol-ecular conformation and packing in its extended structure compared to the previously reported ()-enanti-omer crystal structure. Mol-ecules of this type, comprising aromatic groups with a single side chain terminated in a protonated secondary amine, are commonly found in active anti-depressants.
View Article and Find Full Text PDFDiscrete spin crossover (SCO) heteronuclear cages are a rare class of materials which have potential use in next-generation molecular transport and catalysis. Previous investigations of cubic cage [Fe Pd L ] constructed using semi-rigid metalloligands, found that Fe centers of the cage did not undergo spin transition. In this work, substitution of the secondary metal center at the face of the cage resulted in SCO behavior, evidenced by magnetic susceptibility, Mössbauer spectroscopy and single crystal X-ray diffraction.
View Article and Find Full Text PDFCreating high surface area nanocatalysts that contain stacking faults is a promising strategy to improve catalytic activity. Stacking faults can tune the reactivity of the active sites, leading to improved catalytic performance. The formation of branched metal nanoparticles with control of the stacking fault density is synthetically challenging.
View Article and Find Full Text PDFThe initial peopling of the remote Pacific islands was one of the greatest migrations in human history, beginning three millennia ago by Lapita cultural groups. The spread of Lapita out of an ancestral Asian homeland is a dominant narrative in the origins of Pacific peoples, and although Island New Guinea has long been recognized as a springboard for the peopling of Oceania, the role of Indigenous populations in this remarkable phase of exploration remains largely untested. Here, we report the earliest evidence for Lapita-introduced animals, turtle bone technology and repeated obsidian import in southern New Guinea 3,480-3,060 years ago, synchronous with the establishment of the earliest known Lapita settlements 700 km away.
View Article and Find Full Text PDFGroundwater comprises 95% of the liquid fresh water on Earth and contains a diverse mix of dissolved organic matter (DOM) molecules which play a significant role in the global carbon cycle. Currently, the storage times and degradation pathways of groundwater DOM are unclear, preventing an accurate estimate of groundwater carbon sources and sinks for global carbon budgets. Here we reveal the transformations of DOM in aging groundwater using ultra-high resolution mass spectrometry combined with radiocarbon dating.
View Article and Find Full Text PDFContinual application of nitrogen (N), phosphorous (P) and potassium (K) fertilizer may not return a profit to farmers due to the costs of application and the loss of NPK from soil in various ways. Thus, a combination of NPK granule with a porous biochar (termed here as BNPK) appears to offer multiple benefits resulting from the excellent properties of biochar. Given the lack of information on the properties of NPK and BNPK fertilizers, it is necessary to investigate the characteristics of both to achieve a good understanding of why BNPK granule is superior to NPK granule.
View Article and Find Full Text PDFReduced precipitation in the Miocene triggered the geographic contraction of rainforest ecosystems around the world. In Australia, this change was particularly pronounced; mesic rainforest ecosystems that once dominated the landscape transformed into the shrublands, grasslands, and deserts of today. A lack of well-preserved fossils has made it difficult to understand the nature of Australian ecosystems before the aridification.
View Article and Find Full Text PDFSpin crossover (SCO) materials have long been studied for their inherent electronic switchability, which has been well investigated for potential application in electronic and switching devices. As the technologies for the fabrication of thin films and monolayers continue to develop at an exceedingly rapid pace, an emerging challenge for the SCO community has become the characterisation of spin transitions in the surface layers of a material, as well as understanding the origins of discrepancies observed between SCO in thin films and that of the bulk material. For the manufacture of such devices to become a reality, it is crucial to understand how spin crossover is affected by interactions with the substrate material and within thin films.
View Article and Find Full Text PDFBackground: Anxiety disorders are common in children and youth. Also, in prevention, be it universal, selective or indicated, economic evaluation supports decision-making in the allocation of scarce resources. This review identified and summarised the existing evidence of economic evaluations for the prevention of anxiety disorders in children and adolescents.
View Article and Find Full Text PDFThis study describes a multivariate statistical model (derived using partial least squares regression, PLS-R) that derives charring intensity (reaction temperature and duration) from the attenuated total reflectance (ATR) Fourier Transform Infrared (FTIR) spectra of charcoal. Data for the model was obtained from a library of charcoal samples produced under laboratory conditions at charring intensities (CI) relevant to wildfires and a series of feedstocks representing common tree species collected from Australia. The PLS-R model developed reveals the potential of FTIR to determine the charring intensity of charcoal.
View Article and Find Full Text PDFApplication of iron (Fe)- and silica (Si)-enhanced biochar compound fertilisers (BCF) stimulates rice yield by increasing plant uptake of mineral nutrients. With alterations of the nutrient status in roots, element homeostasis (e.g.
View Article and Find Full Text PDFArtificially stimulated, high-yield microbial production of methane from coal is a challenging problem that continues to generate research interest. Decomposition of organic matter and production of methane from coal are the results of multiple redox reactions carried out by different communities of bacteria and archaea. Recent work by our group (Beckmann et al.
View Article and Find Full Text PDFThis study describes organic thin films prepared under a range of conditions from a model series of bis--alkyl chloro-triazines functionalized with short alkyl chains from ethyl to hexyl. The pure films were characterized using atomic force microscopy (AFM), X-ray diffraction (XRD), Raman spectroscopy, and X-ray photoelectron spectroscopy (XPS). When cast on mica, these compounds assemble as crystalline sheets made up of a synthetic bilayer along the crystallographic -plane with an internal hydrogen-bonded domain between external alkyl chains.
View Article and Find Full Text PDFControlling the formation of nanosized branched nanoparticles with high uniformity is one of the major challenges in synthesizing nanocatalysts with improved activity and stability. Using a cubic-core hexagonal-branch mechanism to form highly monodisperse branched nanoparticles, we vary the length of the nickel branches. Lengthening the nickel branches, with their high coverage of active facets, is shown to improve activity for electrocatalytic oxidation of 5-hydroxymethylfurfural (HMF), as an example for biomass conversion.
View Article and Find Full Text PDFIn this study, we describe the synthesis and molecular properties of anthranilamide-based short peptides which were synthesised via ring opening of isatoic anhydride in excellent yields. These short peptides were incorporated as low molecular weight gelators (LMWG), bola amphiphile, and C-symmetric molecules to form hydrogels in low concentrations (0.07-0.
View Article and Find Full Text PDFBiochar-based compound fertilizers (BCF) and amendments have proven to enhance crop yields and modify soil properties (pH, nutrients, organic matter, structure etc.) and are now in commercial production in China. While there is a good understanding of the changes in soil properties following biochar addition, the interactions within the rhizosphere remain largely unstudied, with benefits to yield observed beyond the changes in soil properties alone.
View Article and Find Full Text PDFA trend between the degree of steric congestion of the Fe(II) coordination environment and the extent of spin transition (percentage completeness) has been observed in a series of halide salts of a dinuclear triple helicate architecture with the general form [Fe]X (where X = Cl for , Br for , and (I)/I for , and is (1,1')-,'-(oxybis(4,1-phenylene))bis(1-(1-imidazol-4-yl)methanimine). Crystal packing densities of adjacent helicates were found to decrease with increasing anion size. Greater steric congestion by neighboring helicates favored the [HS-HS] state of the dinuclear triple helicate architecture.
View Article and Find Full Text PDFDissolved organic matter (DOM) in groundwater is fundamentally important with respect to biogeochemical reactions, global carbon cycling, heavy metal transport, water treatability and potability. One source of DOM to groundwater is from the transport of organic matter from the vadose zone by rainfall recharge. Changes in precipitation patterns associated with natural climate variability and climate change are expected to alter the load and character of organic matter released from these areas, which ultimately impacts on groundwater quality and DOM treatability.
View Article and Find Full Text PDFThe self-assembly of a mixed-spin [FeL] tetrahedral cage is reported. The cage undergoes temperature induced spin-crossover with a 29 K hystereisis. Variable temperature X-ray photoelectron spectroscopy (VT-XPS), combined with SQUID data, allowed differentiation between the surface and bulk magnetic properties.
View Article and Find Full Text PDFMicroorganisms drive most of the major biogeochemical cycles in the ocean, but the rates at which individual species assimilate and transform key elements is generally poorly quantified. One of these important elements is nitrogen, with its availability limiting primary production across a large proportion of the ocean. Nitrogen uptake by marine microbes is typically quantified using bulk-scale approaches, such as Elemental Analyzer-Isotope Ratio Mass Spectrometry (EA-IRMS), which averages uptake over entire communities, masking microbial heterogeneity.
View Article and Find Full Text PDFIn this study, we report the synthesis of glyoxylamide peptide-mimics as self-assembled gels with well-defined molecular structures for topical delivery of ciprofloxacin (CIP). The glyoxylamide peptide mimics successfully formed hydrogels with critical gel concentrations of 0.02-0.
View Article and Find Full Text PDFA major synthetic challenge is to make metal nanoparticles with nanosized branches and well-defined facets for high-performance catalysts. Herein, we introduce a mechanism that uses the growth of hexagonal crystal structured branches off cubic crystal structured core nanoparticles. We control the growth to form Pd-core Ru-branch nanoparticles that have nanosized branches with low index Ru facets.
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