Effect of lithium borate coating on the electrochemical properties of LiCoO2 electrode for lithium-ion batteries

The effect of a protective coating of fused lithium borate, Li3BO3, on the physicochemical and electrochemical characteristics of LiCoO2 has been studied. A cathode material produced by the SCS method using binary organic fuel, glycine and citric acid. The influence of the experiment conditions on the morphology, crystal structure and specific surface of lithium cobaltite was studied. Electrochemical testing of LiCoO2∙nLi3BO3 samples, n = 5 and 7 mass %, has been performed in the cathode Li|Li+-electrolyte|LiCoO2∙nLi3BO3 half-cell using 1M LiPF6 in EC/DMC mixture (1:1) as electrolyte in the 2.7-4.3 V range at normalized discharge current С/10, С/5, С/2. The maximal initial discharge capacity of 185 mAh/g was detected for the samples with 5 mass % Li3BO3. The coulomb efficiency of optimal materials in the 40th cycle was 99.1%

Functional and Structural Properties of Cytoplasmic Tropomyosin Isoforms Tpm1.8 and Tpm1.9

The actin cytoskeleton is one of the most important players in cell motility, adhesion, division, and functioning. The regulation of specific microfilament formation largely determines cellular functions. The main actin-binding protein in animal cells is tropomyosin (Tpm). The unique structural and functional diversity of microfilaments is achieved through the diversity of Tpm isoforms. In our work, we studied the properties of the cytoplasmic isoforms Tpm1.8 and Tpm1.9. The results showed that these isoforms are highly thermostable and differ in the stability of their central and C-terminal fragments. The properties of these isoforms were largely determined by the 6th exons. Thus, the strength of the end-to-end interactions, as well as the affinity of the Tpm molecule for F-actin, differed between the Tpm1.8 and Tpm1.9 isoforms. They were determined by whether an alternative internal exon, 6a or 6b, was included in the Tpm isoform structure. The strong interactions of the Tpm1.8 and Tpm1.9 isoforms with F-actin led to the formation of rigid actin filaments, the stiffness of which was measured using an optical trap. It is quite possible that the structural and functional features of the Tpm isoforms largely determine the appearance of these isoforms in the rigid actin structures of the cell cortex

Explaining the Productivity Advantages of Manufacturing Firms in Russian Urban Agglomerations

This paper empirically analyzes the agglomeration-related productivity premium at the enterprise level of the manufacturing industry in Russia. A settlement is counted as part of an urban agglomeration in two cases: that of a large, central city and that of a town located within 50 kilometers of the central city. Data obtained from a 2009 manufacturing enterprise survey conducted by the Higher School of economics are used, along with linked data on hosting regions and cities. We employ a multilevel model, which allows us to consider firm, urban and regional heterogeneity and test two possible explanations of the productivity advantages of firms in urban agglomerations ? own-sector and all economic activity concentration in the city and the surrounding region. In addition we check if agglomeration productivity premium increases if the city is located within the region opened for international trade. The results suggest that Russian plants in urban agglomerations enjoy 17-21% higher labor productivity. This gain arises as a result of urbanization and external scale economy ? the agglomeration of firms belonging to different industries at both the urban and the regional levels of analysis. We also found that productivity gained from urban agglomeration is the highest in towns with populations of 100,000 to 250,000 people. Localization and clustering ? the own-sector concentration of plants in the city ? is not associated with higher labor productivity. The structure and size of the surrounding economy always matter: in contrast to urban clusters, regional own-industry clustering satisfactorily explains the productivity premium, suggesting that efficient clustering requires a scale economy larger than only a city. If the region is open to trade, has a good road network, attracts migrant workers from other regions and has a mature market with relatively high living standards, urban agglomeration effects will be much stronger. All of our results are robust to changes in estimation technique, sample structure and choice of spatial objects. We conclude with the assumptions for the policy framework. Our results do not imply that the maximization of agglomeration numbers can resolve the issue of low productivity in manufacturing. Rather, we have demonstrated that agglomeration mechanisms rely on urban diversity, scale and openness in the economy. Indeed, these dimensions deserve stimulation through the use of regional policy measures