5 research outputs found
Theoretical Aspects of Social and Economic Development of Municipalities Management System on the Example of Moscow
No full textIn this article basic provisions of system of local self-government, the mechanism of its functioning and questions of social and economic nature on the example of intracity municipalities of Moscow are considered by the author. In the conclusion the author emphasizes that further development of a regulatory framework with gradual increase in powers of recommendations of municipal deputies is necessary for effective implementation of management on places
Enzymatic hydrolysis and fermentation of ultradispersed wood particles after ultrasonic pretreatment
No full textAbstractBackgroundA study of the correlation between the particle size of lignocellulosic substrates and ultrasound pretreatment on the efficiency of further enzymatic hydrolysis and fermentation to ethanol.ResultsThe maximum concentrations of glucose and, to a lesser extent, di- and trisaccharides were obtained in a series of experiments with 48-h enzymatic hydrolysis of pine raw materials ground at 380–400rpm for 30min. The highest glucose yield was observed at the end of the hydrolysis with a cellulase dosage of 10mg of protein (204±21 units CMCase per g of sawdust).The greatest enzymatic hydrolysis efficiency was observed in a sample that combined two-stage grinding at 400rpm with ultrasonic treatment for 5–10min at a power of 10W per kg of sawdust. The glucose yield in this case (35.5g glucose l−1) increased twofold compared to ground substrate without further preparation.ConclusionsUsing a mechanical two-stage grinding of lignocellulosic raw materials with ultrasonication increases the efficiency of subsequent enzymatic hydrolysis and fermentation
Enzymatic hydrolysis and fermentation of ultradispersed wood particles after ultrasonic pretreatment
No full textBackground: A study of the correlation between the particle size of
lignocellulosic substrates and ultrasound pretreatment on the
efficiency of further enzymatic hydrolysis and fermentation to ethanol.
Results: Themaximumconcentrations of glucose and, to a lesser extent,
di- and trisaccharideswere obtained in a series of experiments with
48-h enzymatic hydrolysis of pine rawmaterials ground at 380\u2013400
rpm for 30min. The highest glucose yield was observed at the end of the
hydrolysis with a cellulase dosage of 10 mg of protein (204 \ub1 21
units CMCase per g of sawdust). The greatest enzymatic hydrolysis
efficiency was observed in a sample that combined two-stage grinding at
400 rpm with ultrasonic treatment for 5\u201310 min at a power of 10 W
per kg of sawdust. The glucose yield in this case (35.5 g glucose
l 121) increased twofold compared to ground substrate without
further preparation. Conclusions: Using a mechanical two-stage grinding
of lignocellulosic raw materials with ultrasonication increases the
efficiency of subsequent enzymatic hydrolysis and fermentation
Low-Temperature Properties of the Sodium-Ion Electrolytes Based on EC-DEC, EC-DMC, and EC-DME Binary Solvents
No full textSodium-ion batteries are a promising class of secondary power sources that can replace some of the lithium-ion, lead–acid, and other types of batteries in large-scale applications. One of the critical parameters for their potential use is high efficiency in a wide temperature range, particularly below 0 °C. This article analyzes the phase equilibria and electrochemical properties of sodium-ion battery electrolytes that are based on NaPF6 solutions in solvent mixtures of ethylene carbonate and diethyl carbonate (EC:DEC), dimethyl carbonate (EC:DMC), and 1,2-dimethoxyethane (EC:DME). All studied electrolytes demonstrate a decrease in conductivity at lower temperatures and transition to a quasi-solid state resembling “wet snow” at certain temperatures: EC:DEC at −8 °C, EC:DMC at −13 °C, and EC:DME at −21 °C for 1 M NaPF6 solutions. This phase transition affects their conductivity to a different degree. The impact is minimal in the case of EC:DEC, although it partially freezes at a higher temperature than other electrolytes. The EC:DMC-based electrolyte demonstrates the best efficiency at temperatures down to −20 °C. However, upon further cooling, 1 M NaPF6 in EC:DEC retains a higher conductivity and lower resistivity in symmetrical Na3V2(PO4)3-based cells. The temperature range from −20 to −40 °C is characterized by the strongest deterioration in the electrochemical properties of electrolytes: for 1 M NaPF6 in EC:DMC, the charge transfer resistance increased 36 times, and for 1 M NaPF6 in EC:DME, 450 times. For 1 M NaPF6 in EC:DEC, the growth of this parameter is much more modest and amounts to only 1.7 times. This allows us to consider the EC:DEC-based electrolyte as a promising basis for the further development of low-temperature sodium-ion batteries
