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  • Collins Saunders posted an update 1 week, 2 days ago

    We have studied properties of novel thermotropic mesogenic materials that exhibit both an achiral double gyroid (Ia3[combining macron]d symmetry) and chiral cubic phase (previously assigned the Im3[combining macron]m symmetry). We argue that in the chiral cubic phase molecules form micelles and channels arranged into continuously interconnected hexagons. From the X-ray diffraction experiment supported by modelling, exact positions of hexagons and their connections were deduced and showed to be embedded on a WP (degenerated Neovius) minimal primitive surface. The elastic energy of such a structure is close to the one of the double gyroid phase, which is in agreement with a very low enthalpy change observed at the phase transition. We also argue that the chirality of the phase is related to the lack of mirror symmetry of non-flat hexagons accompanied by an alternating inclination of molecules in the neighbouring segments of hexagon; the chirality of individual hexagon is amplified on the whole hexagon network by steric effects.Magnetic phase control and room temperature magnetic stability in two-dimensional (2D) materials are indispensable for realising advanced spintronic and magneto-electronic functions. Our current work employs first-principles calculations to comprehensively study the magnetic behaviour of 2D CrOCl, uncovering the impact of strain and electric field on the material. Our studies have revealed that uniaxial strain leads to the feasibility of room temperature ferromagnetism in the layer and also detected the occurrence of a ferromagnetic → antiferromagnetic phase transition in the system, which is anisotropic along the armchair and zigzag directions. Beyond such a strain effect, the coupling of strain and electric field leads to a remarkable enhancement of the Curie temperature (Tc) ∼ 450 K in CrOCl. These predictions based on our detailed simulations show the prospect of multi-stimuli magnetic phase control, which could have great significance for realizing magneto-mechanical sensors.We have made high surface area catalysts for the selective oxidation of methanol to formaldehyde. This is done in two ways – (i) by doping haematite with Al ions, to increase the surface area of the material, but which itself is unselective and (ii) by surface coating with Mo which induces high selectivity. Temperature programmed desorption (TPD) of methanol shows little difference in surface chemistry of the doped haematite from the undoped material, with the main products being CO2 and CO, but shifted to somewhat higher desorption temperature. However, when Mo is dosed onto the haematite surface, the chemistry changes completely to show mainly the selective product, formaldehyde, with no CO2 production, and this is little changed up to 10% Al loading. But at 15 wt% Al, the chemistry changes to indicate the presence of a strongly acidic function at the surface, with additional dimethyl ether and CO/CO2 production characteristic of the presence of alumina. Structurally, X-ray diffraction (XRD) shows little chmediately beneath the topmost surface layer of molybdena. It seems like the separate γ-alumina phase is not covered by molybdena and is responsible for the appearance of the acid function products in the TPD.Consumers are demanding healthy nutritious foods rich in protein (both plant and animal) and biologically-active phytochemicals from plants, which can help the body to sustain a stronger immune system and fight against oxidative stress. The aim of this study was to determine the conditions required to enhance the concentration of bioactive phenolics and protein in aggregate particles formed with whey or rice protein isolates and polyphenol-rich berry juices (cranberry and blueberry), and to evaluate properties associated with food structural functionality and stability. Different protein concentrations (10, 15 and 20% w/w) and mixing durations were tested in order to study their effects on particle formation. Addition of juices significantly increased the aggregation of whey proteins in suspensions at pH 4.5, resulting in a trimodal distribution of protein-polyphenol particles sizes at 5 μm, 30 μm, and above 100 μm. However, the addition of polyphenol-rich juices did not markedly alter aggregation or particle size distribution for rice proteins, as compared to rice protein particles formed with imitation juice. The particles formed with 10% w/w whey protein and blueberry juice yielded the highest total phenolic (27 mg g-1 particle) and protein content (805 mg g-1 particle); therefore, only 25 g of protein-polyphenol particles delivered simultaneously 20 g of protein, and the equivalent blueberry polyphenols (∼0.64 g total polyphenolics) in two servings (150 g) of blueberries. Particles formed with whey protein and blueberry juice significantly improved foam stability and drainage half-life. Protein-polyphenol particles can be designed as ingredients to stabilize food structures and to increase delivery of health protective polyphenols and proteins in the diet.Hydroxycinnamic acids (HAs) are widely spread in food and herbal medicines. The bioavailability of HAs largely depends on the absorption and metabolism in enterohepatic circulation, in which gut microbiota plays a vital role. Ivacaftor The present research aims to investigate the metabolism of HAs by gut microbiota, together with the community changes of gut microbiota after cerebral ischemia-reperfusion (I/R) injury. The results showed that non-substituted cinnamic acid (NCA) and sinapic acid (SA) were stable to gut microbiota, while 4-hydrocinnamic acid (4-HA), caffeic acid (CA), and ferulic acid (FA) underwent decarboxylation and hydrogenation after anaerobic incubation. Time-course studies indicated that the gut microbiota from I/R injured rats can catalyze the same reaction, but with a decreased reaction rate. The 16S rRNA sequencing technique was applied to uncover the community changes of gut microbiota. In addition, the metabolites of the three HAs exhibited greater activity in scavenging the DPPH radical and protected PC12 cells against oxidative damage.Electrocatalysis for cathodic oxygen is of great significance for achieving high-performance lithium-oxygen batteries. Herein, we report a facile and green method to prepare an interconnected nanoporous three-dimensional (3D) architecture, which is composed of RuO2 nanogranulates coated with few layers of carbon. The as-prepared 3D nanoporous RuO2@C nanostructure can demonstrate a high initial specific discharge capacity of 4000 mA h g-1 with high round-trip efficiency of 95%. Meanwhile, the nanoporous RuO2@C could achieve stable cycling performance with a fixed capacity of 1500 mA h g-1 over 100 cycles. The terminal discharge and charge potentials of nanoporous RuO2@C are well maintained with minor potential variation of 0.14 and 0.13 V at the 100th cycle, respectively. In addition, the formation of discharge products is monitored by using in situ high-energy synchrotron X-ray diffraction (XRD).