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Computer simulation of shearing deformation in polymer systems with polar groups

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Journal of Advanced Dielectrics 2020年第3期10卷 37-42页

作者： olga G.Maksimova Oleg s.Piskunov Roman A.Gerasimov olga s.Baruzdina Andrew V.Maksimov Laboratory of Mathematical and Computer Modeling Cherepovets state University 5 Lunacharskii Av.Cherepovets 162600Russian Federation Department of Physics Cherepovets state University Lunacharskii Av. Cherepovets 162600Russian Federation

In this work,shear strain modeling in materials consisting of a thin polymer layer(~15 nm),adhesive bonded to a rigid substrate,considered not to be impacted by deformation,was performed.A discrete-continuum model of chains system with a given stiffness with polar groups is *** polymer chain was considered in the framework of the persistene model,and the polar groups were based on the lattice model on the tetragonal *** was assumed that the main contribution to the energy of interchain interactions is due to the potential of the polar groups and was calculated using the Metropolis *** potential interactions between the nearest polar groups of chains included the energy of dipole–dipole interactions(Keesom energy)and the Lennard–Jones *** is taken into account that the possible orientations of the polar groups are determined by the average elongation of the *** showed that the dependence of free energy on the interchain distance has two *** first minimum is characterized by the orientational ordering of the polar groups,the second—by their disordered *** depth and position of the minima depend on temperature,bending stiffness of the chain,the modulus of the dipole moment of the polar groups and the depth of the potential well in the Lennard–Jones energy.A step-by-step simulation of shear strain in a polymer layer in an orientationally disordered state was carried *** obtained stress–strain diagrams make it possible to estimate the value of the elastic limit and also to determine the stresses at the points of phase transitions from a disordered to an orientationally ordered state.

关键词： Polymer systems polar group shearing deformations PVDF Monte Carlo method

Influence of polyolefin fibers on the strength and deformability properties of road pavement concrete

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Journal of Traffic and Transportation Engineering(English Edition) 2019年第4期6卷 407-417页

作者： olga smirnova Alexey Kharitonov Yuriy Belentsov Department of Constructing Mining Enterprises and Underground structures Saint-Petersburg Mining UniversitySaint Petersburg 199106Russia Department of Technology of Building Materials and Metrology Saint-Petersburg State University of Architecture and Civil EngineeringSaint Petersburg 190005Russia Department of Building Materials and Technologies Emperor Alexander I St.Petersburg State Transport UniversitySaint Petersburg 190031Russia

Influence of the type and quantity of polyolefin fibers on the strength properties(compression strength, tensile strength in bending, strength in uniaxial tension), the deformation properties(elastic modulus, Poisson’s coefficient) and the abrasion resistance of cement concrete with water-to-cement ratio within 0.31 e0.55 were stated in the *** ways of fibers introduction into fresh concrete were investigated. It was shown that the fibers introduction method and procedure of mixing are the ways to improve the fibers uniform distribution in fresh concrete. The increase of the bending tensile strength and the uniaxial tensile strength of concrete with fibers reinforcement in comparison with the reference concrete was observed with the water-to-cement ratio decrease. The increase of uniaxial tensile strength at age of 28 days for concrete with macrofibers in amount of4.5 kg/m^3 was 23% and 29%;for macrofibers in quantity of 3 kg/m^3 was 19% and 26% with water-cement ratio equal to 0.49 and 0.31, respectively. The maximum reduction of abrasion in the range of 7.5%e10% was observed in concrete with water-to-cement ratio within0.44 e0.55 for all investigated types of fibers. The influence of fibers on the concrete abrasion with lower W/C ratio was negligible. The results can contribute to the rational use of modified polyolefin fibers in road pavement concrete.

关键词： Road pavement concrete Polyolefin fibers strength Elastic modulus Abrasion Water-to-cement ratio

The forecast of fire impact on Pinus sylvestris renewal in southwestern siberia

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Journal of Forestry Research 2021年第5期32卷 1911-1919页

作者： stanislav Nsannikov Nelly ssannikova Irina VPetrova olga E.Cherepanova Botanical Garden of the Ural Branch of Russian Academy of science 202a8 Marta St.Yekaterinburg 620144Russia

simulation of fire impact on forest floor renewal in pine forests was based on predictions for 2100 by the Canadian Climate Centre for increase in temperatures of by4.5℃and total precipitation by 14%in the West siberian pre-forest-steppes and empirical regression relationships between them and the degree of burnt forest floor,as well as amount of Pinus sylvestris *** was predicted that by 2100,pine regeneration on fire prone sites under the canopy of the dominant forest type will increase by 29-54%compared to the 1980 s but on adjacent open sites,regeneration will decrease twice as *** means that the regeneration potential and pine population stability in pre-forest-steppes will become as poor as it is today.

关键词： Fire Forecast stability Population Mathematical model seeds Imitation model Undergrowth

Carbon coating of air-sensitive insulating transition metal fluorides:An example study on α-Li3FeF6 high-performance cathode for lithium ion batteries

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Journal of Materials science & Technology 2020年第20期52卷 107-115页

作者： Anna Basa sławomir Wojtulewski Beata Kalska-szostko Maciej Perkowski Elena Gonzalo olga Chernyayeva Alois Kuhn Flaviano García-Alvarado Institute of Chemistry University of Bialystokul.K.Ciolkowskiego 1K15-245 BialystokPoland Departamento de Química y Bioquímica Facultad de FarmaciaUniversidad CEU San Pablo28668 Boadilla del MonteMadridSpain Polish Institute of Physical Chemistry Kasprzaka St.44/5201-224 WarsawPoland CIC Energigune Parque Tecnologico de Alava01510 MinanoAlavaSpain

Li_(3)FeF_(6)has been the focus of research of fluorine-based cathode materials for lithium-ion *** of the low electronic conductivity of Li3 FeF6,the decrease of particle size,by an energyconsuming long-time ball milling process with carbon,is necessary to achieve a high electrochemical *** most successful method to enhance electrochemical activity,carbon coating,seemed to be impracticable,so far,for sensitive fluorides like Li3 *** this work,carbon coating on Li3 FeF6 particles has been successfully achieved for the first time,while avoiding both extended hydrolysis and Fe(Ⅲ)-Fe(Ⅱ)*** heat treatment and atmosphere,yielding the maximal transformation of organic carbon to both graphitised and disordered carbon,has been *** coating,with a thickness of approximately 2.5 nm,has been achieved by controlled thermal decomposition of glucose,under air,at 300℃.Raman and X-ray photoelectron spectroscopy(XPs)experiments have proved the existence of carbon and Fe2O3 on the surface of Li3FeF6 *** spectroscopy indicates the presence of organic residues from glucose *** to further reduce the orga nic carbon content results in a decrease of the amorphous carbon coating *** carbon-coated Li3 FeF6 nanoparticles deliver 122 mA h g^(-1)(85%of theoretical capacity)significantly higher than that of a noncoated sample(58 mA h g^(-1)).Even more,a significant beneficial effect of carbon coating on both capacity retention and coulombic efficiency is observed.

关键词： Lithium iron fluoride Hydrolysable fluoride Lithium battery Cathode Carbon coating

Toward nanoscale molecular mass spectrometry imaging via physically constrained machine learning on co-registered multimodal data

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npj Computational Materials 2020年第1期6卷 956-963页

作者： Nikolay Borodinov Matthias Lorenz steven T.King Anton V.Ievlev olga s.Ovchinnikova Center for Nanophase Materials sciences Oak Ridge National LaboratoryOak RidgeTN 37831USA University of Tennessee KnoxvilleTNUSA

Mass spectrometry imaging(MsI)plays a pivotal role in investigating the chemical nature of complex systems that underly our understanding in biology and *** fields of life science such as proteomics,lipidomics and metabolomics benefit from the ability to simultaneously identify molecules and pinpoint their distribution across a ***,achieving the necessary submicron spatial resolution to distinguish chemical differences between individual cells and generating intact molecular spectra is still a challenge with any single imaging ***,we developed an approach that combines two MsI techniques,matrix-assisted laser desorption/ionization(MALDI)and time-of-flight secondary ion mass spectrometry(ToF-sIMs),one with low spatial resolution but intact molecular spectra and the other with nanometer spatial resolution but fragmented molecular signatures,to predict molecular MsI spectra with submicron spatial resolution.

关键词： modal mass constrained

A “false positive” octreoscan in ileal Crohn’s disease

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World Journal of Gastroenterology 2008年第34期14卷 5349-5352页

作者： Alberto Fernandez olga Tabuenca Angeles Peteiro Gastroenterology Department POVISA Hospital Nuclear Medicine Department POVISA Hospital Pathology Department POVISA Hospital

We present a case report of a patient with a suspicious ileal carcinoid tumour. Clinical examination as well as computer tomograghy (CT) scan suggested a tumour. Octeotride scan showed uptake in the same bowel loop reported as pathological in CT. The patient underwent surgery and biopsy which reported Crohn’s disease (CD). The interest in the case is due to the fact that this is, to the best of our knowledge, the second report of Crohn’sdisease as a cause of false positive octeotride scan. Unfortunately, no somatostatin recptors could be found in the sample, so further studies should be performed.

关键词： Crohn's disease Carcinoid tumour Octreoscan somatostatin receptor scintigraphy ^111In-DTPA- octreotido

Empty nose syndrome pathogenesis and cell-based biotechnology products as a new option for treatment

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World Journal of stem Cells 2021年第9期13卷 1293-1306页

作者： Inna M Gordiienko olga s Gubar Roman sulik Taras Kunakh Igor Zlatskiy Alona Zlatska Biotechnology Laboratory Medical Company“Good Cells”Kyiv 03115Ukraine R.E.Kavetsky Institute of Experimental Pathology Oncology and Radiobiology NAS of UkraineKyiv 03022Ukraine Institute of Molecular Biology and Genetics NAs of Ukraine Kyiv 03143Ukraine state Institute of Genetic and Regenerative Medicine National Academy of Medical Sciences of UkraineKyiv 04114Ukraine

Empty nose syndrome (ENs) is a rare complication that develops after partial orcomplete turbinectomy. The main feature of ENs is paradoxical nasal obstructionfeeling despite objectively wide nasal airway. ENs pathogenesis is multifactorialand includes changes in laminar physiological airflow, disruption of mucosafunctions and deficient neural sensation. This leads to the development of ENssymptomatology such as dyspnea, nasal dryness, nasal burning, nasalobstruction, feeling of suffocation and even comorbid psychiatric disorders thatsignificantly impairs life quality. specific effective treatment of ENs does not existup to date. In this review we outline existing biomaterial for surgical reconstitutionof nasal anatomy and discuss the perspective of stem cell-based technologiesin ENs management. The main focus is directed to justification ofrationality application of adult mesenchymal stem cells (MsCs) from differenttissues origin and neural crest-derived stem cells (NCsCs) based on their intrinsicbiological properties. MsCs transplantation may stimulate mucosa tissueregeneration via trophic factors secretion, direct transdifferentiation into epithelialcells and pronounced immunosuppressive effect. From the other hand, NCsCsbased on their high neuroprotective properties may reconstitute nerve structureand functioning leading to normal sensation in ENs patients. We postulate thatapplication of cell-based and tissue-engineered products can help to significantlyimprove ENs symptomatology only as complex approach aimed at reconstitutionof nasal anatomy, recovery the nasal mucosa functionality and neural tissuesensation.

关键词： Empty nose syndrome stem-cell-based technologies Implants biomaterials Grafts Hydrogels Mesenchymal stem cells

Lu Xun in the Rhetoric of the sino-soviet split： A View from Contemporary Russia

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Frontiers of Literary studies in China-selected Publications from Chinese Universities 2013年第3期7卷 483-493页

作者： olga Medvedeva Department of AHKR University of Bergen Postbox 7805 NO-5020 Bergen Norway

The historical role of the prominent Chinese writer, social activist and thinker Lu Xun （1881-1936）, is difficult to overestimate. His works influenced social change within China and became recognized internationally. For these and other reasons, he was of particular interest in the soviet Union. since 1932, his works have been published in numerous editions in Russian and have received a great deal of scholarly attention in the soviet Union. such unprecedented attention was initially based on the idea that he held similar revolutionary sentiments to those prevailing in the soviet Union. Later, from the second half of the 1960s to the early 1970s, the ideological disagreements between the soviet Union and China influenced the direction of Lu Xun studies in the soviet Union. soviet leader Khrushchev called for peaceful coexistence with the capitalist West, while Mao Zedong stressed the universal character of the proletarian revolution. Lu Xun was highly respected in both the UssR and China, and thus became an influential tool in this polemic. But, for soviet scholars, this renewed focus on Lu Xun offered an opportunity to provide a new perspective on the writer＇s works. This paper analyzes how the sino-soviet split influenced Russian academics＇ positions on Lu Xun. The focus is on the three main points of contention in the ideological disagreements between the PRC and the UssR. First, soviet critics focused on the psychological aspects and individualism in the Lu Xun＇s works. second, a special focus on humanistic elements in the writer＇s ideas can be seen as a result of the soviet disagreement with the Cultural Revolution＇s period. Third, by pointing to the internationalist aspects of Lu Xun＇s writings, soviet scholars attempted to expose the sinocentric political attitudes of the ruling circles in China.

关键词： Lu Xun sino-soviet split Russian intellectual history

Physiological and biochemical characteristic of Miscanthus×giganteus grown in heavy metal-oil sludge co-contaminated soil

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Journal of Environmental sciences 2022年第5期34卷 114-125页

作者： Anna Muratova Yelena Lyubun Irina sungurtseva olga Turkovskaya Asil Nurzhanova Institute of Biochemistry and Physiology of Plants and Microorganisms RAs Saratov 410015Russia Institute of Plant Biology and Biotechnology Almaty 050040Kazakhstan

The effect of oil sludge and zinc,present in soil both separately and as a mixture on the physiological and biochemical parameters of Miscanthus×giganteus plant was examined in a pot *** opposite effect of pollutants on the accumulation of plant biomass was established:in comparison with uncontaminated control the oil sludge increased,and Zn reduced the root and shoot *** sludge had an inhibitory effect on the plant photosynthetic apparatus,which intensified in the presence of *** specific antioxidant response of M.×giganteus to the presence of both pollutants was a marked increase in the activity of superoxide dismutase(mostly owing to oil sludge)and glutathione-s-transferase(mostly owing to zinc)in the *** participation of glutathione-s-transferase in the detoxification of both the organic and the inorganic pollutants was *** inhibited the activity of laccase-like oxidase,whereas oil sludge promoted laccase and ascorbate oxi-dase *** finding suggests that these enzymes play a part in the oxidative detox-ification of the organic *** both pollutants used jointly,Zn accumulation in the roots increased 6-fold,leading to increase in the efficiency of soil clean-up from the *** turn,Zn did not significantly affect the soil clean-up from oil *** study shows for the first time the effect of co-contamination of soil with oil sludge and Zn on the phys-iological and biochemical characteristics of the bioenergetic plant M.×*** data obtained are important for understanding the mechanisms of phytoremediation with this plant.

关键词： Miscanthus×giganteus Oil sludge Zinc Antioxidant enzymes Oxidative enzymes