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High selectivity of CO2 hydrogenation to CO by controlling the valence state of nickel using perovskite
The selectivity of CO2 hydrogenation can be significantly tuned by controlling the valence state of nickel using lanthanum–iron–nickel perovskites. Nickel with higher valence states weakens the binding of CO and increases the activation barrier for further CO hydrogenation, leading to a higher CO se...

Direct Metal-free, Base Catalysed sp2 C-H Functionalization in Sulfonamidation of 1,4-Naphthoquinones Using Sulfonyl azides
A novel metal-free, base catalysed sp2 C-H functionalization in the sulfonyl amidation of 1,4-naphthoquinones via a [3+2] cycloaddition reaction using sulfonyl azides under mild reaction conditions is reported. In this straightforward, atom- and step-economical protocol, the active alkene moiety of ...

Predictability of the onset of spiking and bursting in complex chemical reactions
For three complex chemical reactions displaying intricate dynamics, we assess the effectiveness of a recently proposed quantitative method to forecast bursting and large spikes, i.e. extreme events. Specifically, we consider predicting extreme events in (i) a copper dissolution model where Bassett a...

Graphene Oxide based Fluorescence Sensor for Cucurbit[7]uril
Rhodamine B (RhB) anchored reduced Graphene oxide (RhBGO) offers a very sensitive and selective sensing potential for cucurbit[7]uril (CB[7]). Except CB[7], RhBGO did not respond for other cucurbituril homologues and for β-cyclodextrin (β-CD) presumably due to their inability to pull off RhB from Rh...

Mobility of Hydrous Species in Amorphous Calcium/Magnesium Carbonates
Amorphous calcium carbonate (ACC) is commonly found in many biological materials. As ACC readily crystallizes into calcite, stabilizers, such as anions, cations or macromolecules often occur to avoid or delay unwanted crystallization. In biogenic ACC, magnesium is commonly present as one of the stab...

The efficiency of 18F labelling of a prostate specific membrane antigen ligand via strain-promoted azide–alkyne reaction: reaction speed versus hydrophilicity
Here we report the 18F labeling of a prostate specific membrane antigen (PSMA) ligand via a strain promoted oxa-dibenzocyclooctyne (ODIBO)- or bicyclo[6.1.0]nonyne (BCN)-azide reaction. Although ODIBO reacts with azide 20 fold faster than BCN, in vivo PET imaging suggests that 18F-BCN-azide-PSMA dem...

Selective radiolabelling with 68Ga under mild conditions: a route towards a porphyrin PET/PDT theranostic agent
A theranostic conjugate for use as a positron emission tomography (PET) radiotracer and as a photosensitiser for photodynamic therapy (PDT) has been synthesised. A water-soluble porphyrin was coupled with the bifunctional chelate, H4Dpaa.ga. This conjugate is capable of rapid 68Ga complexation under...

Synthesis, photophysical, antibacterial and larvicidal studies on triazolophanes with 5-nitro isophthalate functionality at the intraannular position
1 : 1 and 2 : 2 oligomeric triazolophanes with 5-nitro isophthalate and triazolyl functionalities at the intraannular position have been synthesized by copper(i) catalyzed 1,3 dipolar cycloaddition of the corresponding propargylic esters with various phenyl substituted aliphatic azides under mild co...

Fine-tuning polyoxometalate non-linear optical chromophores: a molecular electronic “Goldilocks” effect
A new aryl-imido polyoxometalate non-linear optical chromophore (POMophore) with a diphenylamino donor group attains the highest βzzz, 0 value (196 × 10−30 esu by Hyper-Rayleigh Scattering, HRS), and best transparency/non-linearity trade off yet for such materials. Stark spectroscopic and DFT invest...

Slow magnetic relaxation in a {CoIICoIII2} complex containing a high magnetic anisotropy trigonal bipyramidal CoII centre
We report a trinuclear mixed-valence {CoIICoIII2} complex, where the CoII centre adopts a trigonal bipyramidal geometry, leading to a large, easy-plane magnetic anisotropy and field-induced slow magnetic relaxation with a Raman-like relaxation process....

Random mixed-metal Co1-xNix single-chain magnets with simultaneous azide, carboxylate and tetrazolate bridges
This paper reports the magnetic properties of a series of isomorphous metal-organic frameworks based on random heterometallic Co1-xNix chains with simultaneous azide, carboxylate and tetrazolate bridges. All the mixed-metal compounds show intrachain FM interactions, field-induced metamagnetism, and ...

Hysteretic spin crossover in isomeric iron(II) complexes
Two mononuclear iron(II) complexes with isomeric N,N,N-tridentate pyrimidine-based ligands were synthesized. Both complexes show reproducible hysteretic spin crossover. The low spin state to high spin state switching is cooperative due to autocatalysis....

Elucidating the Performance and Unexpected Stability of Partially Coated Water-Splitting Silicon Photoanodes
H2 is an ideal energy carrier because it has a high energy density, it can be easily stored, transported, and readily used to power electrical devices. Like photosynthesis, where photons are converted into energy-rich molecules, sunlight energy can be converted into H2 and O2 using photoelectrochemi...

Excitation spectroscopic and synchronous fluorescence spectroscopic analysis of the origin of aggregation-induced emission in N,N-diphenyl-1-naphthylamine-o-carborane derivatives
We have synthesised mono-(NpCb) and bis-[(N,N-phenyl-1-naphthylamino)benzo]-o-caboranes (NpCbNp), which show anomalously intense aggregation-induced emission (AIE) at long wavelengths and monomer emission at short wavelengths. The actual concentration of the aggregator in intense AIE is very low, so...

First-principles studies of polar perovskite KTaO3 surfaces: structural reconstruction, charge compensation, and stability diagram
Polar perovskite oxides are of considerable interest for developing advanced functional materials with exceptional electronic properties for their unique polar characters. A cleavage of polar perovskite oxides along the charged layers leads to an electrostatic instability on the cleaved surfaces, an...


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