Local Structure Analysis and Modelling of Lignin-Based Carbon Composites through the Hierarchical Decomposition of the Radial Distribution Function

Carbonized lignin has been proposed as a sustainable and domestic source of activated, amorphous, graphitic, and nanostructured carbon for many industrial applications as the structure can be tuned through processing conditions. However, the inherent variability of lignin and its complex physicochemical structure resulting from feedstock and pulping selection make the Process-Structure-Property-Performance (PSPP) relationships hard to define. In this work, radial distribution functions (RDFs) from synchrotron X-ray and neutron scattering of lignin-based carbon composites (LBCCs) are investigated using the Hierarchical Decomposition of the Radial Distribution Function (HDRDF) modelling method to characterize the local atomic environment and develop quantitative PSPP relationships. PSPP relationships for LBCCs defined by this work include crystallite size dependence on lignin feedstock as well as increasing crystalline volume fraction, nanoscale composite density, and crystallite size with increasing reduction temperature.     

Cyanines comprising barbiturate group facilitate NIR-light assisted ATRP under anaerobic and aerobic conditions at two wavelengths using Fe(III) catalyst

Cyanines with heptamethine pattern namely 5-(6-(2-(3-ethyl-1,1-dimethyl-1H-benzo[e]indol-2(3H)-ylidene)ethylidene)-2-(2-(3-ethyl-1,1-dimethyl-1H-benzo[e]indol-3-ium-2yl) vinyl) cyclo-hex-1-en-1-yl)-1,3-dimethyl-2,6-dioxo-1,2,3,6-tetrahydropyrimidin-4-olate comprising a barbiturate group facilitate controlled radical polymerization using FeBr₃ in the ppm range applying radiation at 790 nm. Tris(4-methoylphenyl)phosphine, Tris(2-pyridylmethyl)amine or tetrabutylammonium bromide served as ligand. The latter showed the best performance resulting in a system needing no amino nitrogen for photo-ATRP. Ethyl α-bromophenylacetate worked as initiator. The cyanine interacts with FeBr₃ resulting in a new absorption band at 877 nm that also resulted in formation of polymer exhibiting similar molecular weight but higher dispersity compared to that obtained by 790 nm radiation by exposure with a light-emitting diode (LED) emitting at 870 nm. This explains the reactivity of the system while other cyanines such as 2-[2-[3-[2-(1,3-Dihydro-1,3,3-trimethyl-2H-indol-2-ylidene)-ethylidene]-2-(1-phenyl- 1H-tetrazol-5-ylsulfanyl)-1-cyclohexen-1-yl]-ethenyl]-1,3,3-trimethyl-3H-indolium chloride showed no activity by exposure at 790 nm in combination with FeBr₃/Br⁻. Controlled radical polymerization was confirmed by successful chain extension and block copolymerization experiments resulting in polymers, which exhibit a dispersity of about 1.3. Interestingly, the new system comprising the aforementioned barbiturate substituted cyanine, FeBr₃/Br⁻ and ethyl α-bromophenylacetate showed a certain oxygen tolerance. Polymers obtained exhibited similar dispersity as those made under inert conditions.     

Synthesis of functionalized tetrahydropyridones by the tandem Knoevenagel—Michael—intramolecular ammonolysis—alkylation reaction

Russian Chemical Bulletin - The tandem Knoevenagel—Michael—intramolecular ammonolysis—alkylation reaction was used to synthesize functionalized tetrahydropyridones. The molecular...     

Photoconversions of 15-crown-5-containing styryl dye and its complex with barium cation in the presence of cucurbit[7,8]urils

Russian Chemical Bulletin - Photophysical processes and photochemical reactions of a 15-crown-5-containing styryl dye of the pyridine series and its complexes with barium perchlorate in water in...     

Structure of the polymer chain of poly(1,3-pentadiene) synthesized using a stereospecific catalytic system

Russian Chemical Bulletin - The structure of polymer chain of poly(1,3-pentadiene) synthesized via a stereospecific polymerization catalyzed by a system based on neodymium trichloride was...     

Electrochemical and Transport Characteristics of Membrane Systems in the Electronanofiltration Separation of Solutions Containing Ammonium Nitrate and Potassium Sulfate

Russian Journal of Electrochemistry - Electrochemical and transport characteristics of systems equipped with OPMN-P and OFAM-K membranes during operation in electronanofiltration cell are studied...     

Reaction of N′-(Arylmethylidene)-2-oxo-2H-chromene-3-carbohydrazides with Methyl 1-Bromocycloalkanecarboxylates and Zinc

Russian Journal of General Chemistry - Depending on the ring size in the Reformatsky reagent and the nature of substituents in arylmethylidene fragment, the reactions of Reformatsky reagents...     

Tensimetric Study of the Tris(2,2,6,6-tetramethylheptan-3,5-dionato)yttrium(III) Dissociation in a Gas Phase

Russian Journal of General Chemistry - The saturated and unsaturated vapor pressures of tris(2,2,6,6-tetramethylheptane-3,5-dionato)yttrium(III), Y(thd)3, were measured by the static method with a...     

A New Metal-Organic Framework: Product of Solvothermal Synthesis in 3D-Printed Autoclaves

Russian Journal of Coordination Chemistry - A new metal-organic framework {Zn4(BDC)3(OAc)2(DMF)4} (BDC = terephthalate anion) was synthesized under solvothermal conditions in a 3D-printed...     

exo- and endo-Complexes of Fe(0) with Carbon Allotropic Modifications on the Example of Fullerene С60: a Density Function Theory Study

Russian Journal of General Chemistry - Structures of exo- and endo-complexes of fullerene C60 with zero-valent Fe0, in which the metal is localized inside and outside fullerene molecule,...