A Water-Soluble Sodium Pectate Complex with Copper as an Electrochemical Catalyst for Carbon Dioxide Reduction

A selective noble-metal-free molecular catalyst has emerged as a fruitful approach in the quest for designing efficient and stable catalytic materials for CO₂ reduction. In this work, we report that a sodium pectate complex of copper (PG-NaCu) proved to be highly active in the electrocatalytic conversion of CO₂ to CH₄ in water. Stability and selectivity of conversion of CO₂ to CH₄ as a product at a glassy carbon electrode were discovered. The copper complex PG-NaCu was synthesized and characterized by physicochemical methods. The electrochemical CO₂ reduction reaction (CO₂RR) proceeds at −1.5 V vs. Ag/AgCl at ~10 mA/cm² current densities in the presence of the catalyst. The current density decreases by less than 20% within 12 h of electrolysis (the main decrease occurs in the first 3 h of electrolysis in the presence of CO₂). This copper pectate complex (PG-NaCu) combines the advantages of heterogeneous and homogeneous catalysts, the stability of heterogeneous solid materials and the performance (high activity and selectivity) of molecular catalysts.     

Palladium Aryl Sulfonate Phosphine Catalysts for the Copolymerization of Acrylates with Ethene

The reaction of 2‐[bis(2‐methoxy‐phenyl)phosphanyl]‐4‐methyl‐benzenesulfonic acid (a) and 2‐[bis(2′,6′‐dimethoxybiphenyl‐2‐yl)phosphanyl]benzenesulfonic acid (b) with dimethyl(N,N,N′,N′‐tetramethylethylenediamine)‐palladium(II) (PdMe₂(TMEDA)) leads to the formation of TMEDA bridged palladium based polymerization catalysts ( 1a and 1b ). Upon reaction with pyridine, two mononuclear catalysts are formed ( 2a and 2b ). These catalysts are able to homopolymerize ethylene and also copolymerize ethylene with acrylates or with norbornenes. With ligand b , high molecular weight polymers are formed in high yields, but higher comonomer incorporations are obtained with ligand a .

     

15N MRI of SLIC-SABRE Hyperpolarized 15N-Labelled Pyridine and Nicotinamide

Magnetic Resonance Imaging (MRI) is a powerful non-invasive diagnostic method extensively used in biomedical studies. A significant limitation of MRI is its relatively low signal-to-noise ratio, which can be increased by hyperpolarizing nuclear spins. One promising method is Signal Amplification By Reversible Exchange (SABRE), which employs parahydrogen as a source of hyperpolarization. Recent studies demonstrated the feasibility to improve MRI sensitivity with this hyperpolarization technique. Hyperpolarized ¹⁵N nuclei in biomolecules can potentially retain their spin alignment for tens of minutes, providing an extended time window for the utilization of the hyperpolarized compounds. In this work, we demonstrate for the first time that radio-frequency-based SABRE hyperpolarization techniques can be used to obtain ¹⁵N MRI of biomolecule 1-¹⁵N-nicotinamide. Two image acquisition strategies were utilized and compared: Single Point Imaging (SPI) and Fast Low Angle SHot (FLASH). These methods demonstrated opportunities of high-field SABRE for biomedical applications.     

Diimidazo[4,5-b:4′,5′-e]pyridine: synthesis and nucleophilic aromatic substitution reaction

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The pyramidal life cycle of economic structures

The pyramidal character of life cycles of economic structures is empirically confirmed on the basis of official statistical data of the years 2003 and 2004. The ergodic hypothesis is applied as one of methods of economic forecasting in evolutionary economics, econophysics and applied researches.     

Photoelectron spectra of some β-diketonates of europium

Physicotechnical Research Institute of the Far Eastern State University. Chemical Institute of the Far Eastern Branch, Academy of Sciences of the USSR. Translated from Zhurnal Strukturnoi Khimii, Vol. 30, No. 3, pp. 147–149, May–June, 1989.     

A facile high-yield solvothermal route to tin phosphide Sn4P3

An effective method of synthesis of tin phosphide Sn₄P₃ starting from metallic tin and amorphous red phosphorus by a low-temperature (200 °C) solvothermal reaction in ethylenediamine is offered. The key parameters of this process - duration, temperature, and the ratio of initial components (Sn/P) are studied. The structure, phase composition, and morphology of the products are investigated using powder X-ray diffraction and scanning electron microscopy. Different synthetic ways for tin phosphide are discussed and compared with the proposed one. The mechanism of solvothermal preparation of tin phosphide in ethylenediamine is discussed. It is shown that the proposed solvothermal method opens up the possibility of preparing other metal-rich phosphides.     

A new synthetic route to chiral 3-aryl-5-ethyl-1,4,2-oxazaphosphorines

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The features of hydrogen ignition over Pt and Pd foils at low pressures

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