Catalytic enamines from dialkylamide-dialkylacetals

The formation of a transient enamine derived from DMF-DMA provides an effective alternative to the harsh conditions normally required for the nucleophilic addition of base-activated methylene compounds to a carbonyl group. Organocatalysts formed from dialkylamide-dialkylacetals in this manner may provide extensive synthetic utility for a number of well-established reactions in which the formation of enolates and enamines has been employed.     

An Electrolytic Zn–MnO2 Battery for High‐Voltage and Scalable Energy Storage

Zinc‐based electrochemistry is attracting significant attention for practical energy storage owing to its uniqueness in terms of low cost and high safety. However, the grid‐scale application is plagued by limited output voltage and inadequate energy density when compared with more conventional Li‐ion batteries. Herein, we propose a latent high‐voltage MnO₂ electrolysis process in a conventional Zn‐ion battery, and report a new electrolytic Zn–MnO₂ system, via enabled proton and electron dynamics, that maximizes the electrolysis process. Compared with other Zn‐based electrochemical devices, this new electrolytic Zn–MnO₂ battery has a record‐high output voltage of 1.95 V and an imposing gravimetric capacity of about 570 mAh g^?1, together with a record energy density of approximately 409 Wh kg^?1 when both anode and cathode active materials are taken into consideration. The cost was conservatively estimated at <US$ 10 per kWh. This result opens a new opportunity for the development of Zn‐based batteries, and should be of immediate benefit for low‐cost practical energy storage and grid‐scale applications.     

Crosslinking Allosteric Sites on the Nucleosome

Targeting defined histone protein sites in chromatin is an emerging therapeutic approach that can potentially be enhanced by allosteric effects within the nucleosome. Here we characterized a novel hetero‐bimetallic compound with a design based on a nucleosomal allostery effect observed earlier for two unrelated drugs—the Ru^II antimetastasis/antitumor RAPTA‐T and the Au^I anti‐arthritic auranofin. The Ru^II moiety binds specifically to two H2A glutamate residues on the nucleosome acidic patch, allosterically triggering a cascade of structural changes that promote binding of the Au^I moiety to selective histidine residues on H3, resulting in cross‐linking sites that are over 35 Å distant. By tethering the H2A‐H2B dimers to the H3‐H4 tetramer, the hetero‐bimetallic compound significantly increases stability of the nucleosome, illustrating its utility as a site‐selective cross‐linking agent.     

Negative Charging of Transition‐Metal Phosphides via Strong Electronic Coupling for Destabilization of Alkaline Water

Heterogeneous electrocatalysis typically involves charge transfer between surface active sites and adsorbed species. Therefore, modulating the surface charge state of an electrocatalyst can be used to enhance performance. A series of negatively charged transition‐metal (Fe, Co, Ni, Cu,and NiCo) phosphides were fabricated by designing strong electronic coupling with hydr(oxy)oxides formed in situ. Physicochemical characterizations, together with DFT computations, demonstrate that strong electronic coupling renders transition‐metal phosphides negatively charged. This facilitates destabilization of alkaline water adsorption and dissociation to result in significantly improved H₂ evolution. Negatively charged Ni₂P/nickel hydr(oxy)oxide for example exhibits a significantly low overpotential of 138 mV at 100 mA cm^?2, superior to that without strong electronic coupling and also commercial Pt/C.     

Flow-injection determination of phosphate with a cadmium ion-selective electrode

A flow-injection method is described, in which phosphate standards are introduced into a reagent stream containing Cd(2+) ,resulting in the formation of Cd(3)(PO(4))(2). The associated reduction in free metal concentration is sensed by a cadmium-selective electrode. With the exception of major interference from iodide and moderate interference from bromide and thiocyanate, the system exhibits excellent response to phosphate and selectivity over several common anions in solutions buffered at pH 8.4. A maximum sampling rate of 160/hr is possible for phosphate standards in the concentration range 10(-1)-10(-1)M with a 10(-4)M Cd(2+) reagent stream at a total flow-rate (carrier and reagent stream combined) of 8.4 ml/min.     

Using a liquid emulsion membrane system for the encapsulation of organic and inorganic substrates within inorganic microcapsules

We report the development of a novel technique for the encapsulation of molecular and condensed organic and inorganic substrates within hollow calcium carbonate microspheres; the process utilises precipitation at the oil-water interface of a pseudovesicular water-in-oil-in-water emulsion liquid membrane (ELM) system in order to create an inorganic shell around the pre-dispersed media.     

Bilayer-by-bilayer antiferroelectric ordering in freely suspended films of an achiral polymer-monomer liquid crystal mixture

Thin freely suspended films of a mixture of an achiral side-chain liquid crystal polymer and its monomer have been studied with depolarized reflected light microscopy. We observe that regions with an odd number of bilayers exhibit a net spontaneous polarization in the tilt plane of the molecules, while regions with an even number of bilayers have no net polarization. These odd-even effects are direct evidence that the tilted smectic bilayers are anticlinic at the polymer backbone and synclinic at bilayer interface and confirm that the phase is bilayer-by-bilayer antiferroelectric.