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Non-Isothermal Degradation Kinetics of Hybrid Copolymers Containing Thermosensitive and Polypeptide Blocks

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Open Journal of Polymer Chemistry 2012年第3期2卷 91-98页

作者： emilya D. ivanova Ivaylo V. Dimitrov Velyana G. Georgieva Sevdalina Christova Turmanova Department of Materials Science Burgas Prof. Assen Zlatarov University Burgas Bulgaria Department of Physical Chemistry Burgas Prof. Assen Zlatarov University Burgas Bulgaria Institute of Polymers Bulgarian Academy of Sciences Sofia Bulgaria

Novel, self-associating hybrid copolymers were synthesized via controlled ring-opening polymerization of N-carboxyanhydride of Z-L-lysine (Z-L-Lys-NCA), initiated by amino-functional macroinitiators. A poly(N-isopropylacry-lamide) (PNIPAm)-based macroinitiator containing 10 mol% of polyoxyethylene grafts and a terminal primary amine group in the form of ammonium hydrochloride (PNIPAm-g-PEО) was synthesized and used to initiate the ammonium- mediated ring-opening polymerization of NCA described by Dimitrov and Schlaad [1]. Thus, hybrid copolymers ((PNIPAm-g-PEO)-b-PLys) with controlled molar-mass characteristics and functionality were obtained. The potential applications of PNIPAm-based copolymers in the systems for controlled drug release, immobilization of enzymes and protein purification have aroused great interest in the studies of their properties and behaviour. The thermal stability and thermodynamic properties of the copolymers obtained were studied. The differential thermal analysis of polyfunctional hybrid copolymers (PNIPAm-g-PEO)-b-PLys) showed that thermooxidative destruction occurs in two stages: primary, of the unstable fragments (grafted chains of PEO);and secondary, of the main polymer chains of poly(N-isopropylacry-lamide) and poly(L-lysine). The kinetics of thermal degradation was evaluated and the values of the activation energy of the degradation process, changes of Gibbs free energy, enthalpy and entropy for the formation of the activated complex were also calculated.

关键词： Self-Associating Hybrid Copolymers N-Carboxyanhydride of Z-L-Lysine (Z-L-Lys-NCA) Thermal Stability Properties Non-Isothermal Degradation Kinetics

Phase transitions and degradation/oxidation mechanisms in lead-free CsSnI3 halide perovskites

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CLEAN ENERGY 2024年第3期8卷 109-115页

作者： ivanova, Alexandra Golikova, Margarita Luchnikov, Lev Gostishchev, Pavel Shetinin, Igor Voronov, Victor Saranin, Danila Khovaylo, Vladimir Natl Univ Sci & Technol MISIS NUST MISIS Leninsky Ave 4 Moscow 119049 Russia Belgorod State Univ Pobedy St 85 Belgorod 308015 Russia

Halide perovskites possess ultra-low thermal conductivity and show high potential for thermoelectric devices. The chemical properties and molecular structure of halide perovskite materials are not completely stable under ambient conditions, which hinders their use in thermoelectric generators. Changes in the properties of bulk halide perovskite thermoelectrics are accompanied by partial phase transitions and surface oxidation processes. In this paper, we conducted a comprehensive study of the transport and structural properties of CsSnI3, which were pristine by vacuum melting followed by spark plasma sintering. The research results on the electrical transport of these materials revealed that exposure to an inert atmosphere does not deteriorate stability and the properties of the materials remain unchanged. However, prolonged exposure to air leads to a significant degradation of the electrical transport properties. Contrary to thin-film samples, the shift to the double perovskite structure from the perovskite one is limited to a specific surface layer. This change significantly influences the electrical transport of the material while maintaining the essential properties of both perovskite types. [GRAPHICS]

关键词： halide perovskites degradation oxidation transport properties surface STABILITY PHOTOLUMINESCENCE CONDUCTIVITY MOBILITY

Non-Isothermal Degradation Kinetics of Hybrid Copolymers Containing Thermosensitive and Polypeptide Blocks

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Current and further trajectories in designing functional materials for solid oxide electrochemical cells:A review of other reviews

Open Journal of Polymer Chemistry（高分子化学期刊） 2012年第3期

作者： emilya D. ivanova Ivaylo V. Dimitrov Velyana G. Georgieva Sevdalina Christova Turmanova

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Journal of Energy Chemistry 2024年第7期94卷 302-331页

作者： Stanislav Baratov Elena Filonova Anastasiya ivanova Muhammad Bilal Hanif Muneeb Irshad Muhammad Zubair Khan Martin Motola Sajid Rauf Dmitry Medvedev Hydrogen Energy Laboratory Ural Federal University620002 EkaterinburgRussia Institute of Natural Sciences and Mathematics Ural Federal University620002 EkaterinburgRussia Department of Inorganic Chemistry Faculty of Natural SciencesComenius University BratislavaIlkovicova 6Mlynska Dolina84215 BratislavaSlovakia State Key Laboratory for Mechanical Behavior of Materials School of Materials Science and EngineeringXi'an Jiaotong UniversityXi'an 710049ShaanxiChina Department of Physics University of Engineering and TechnologyLahore 54890Pakistan Pak-Austria Fachhochschule:Institute of Applied Sciences and Technology Mang Haripur 22621Khyber PakhtunkhwaPakistan College of Mechatronics and Control Engineering Shenzhen UniversityShenzhen 518000GuangdongChina Laboratory of Electrochemical Devices Based on Solid Oxide Proton Electrolytes Institute of High Temperature Electrochemistry620066 EkaterinburgRussia

Complex oxides are an important class of materials with enormous potential for electrochemical *** on their composition and structure,such complex oxides can exhibit either a single conductivity(oxygen-ionic or protonic,or n-type,or p-type electronic)or a combination thereof gener-ating distinct dual-conducting or even triple-conducting *** properties enable their use as diverse functional materials for solid oxide fuel cells,solid oxide electrolysis cells,permeable membranes,and gas *** literature review shows that the field of solid oxide materials and related electro-chemical cells has a significant level of research engagement,with over 8,000 publications published since *** manual analysis of such a large volume of material is ***,by examining the review articles,it is possible to identify key patterns,recent achievements,prospects,and remaining *** perform such an analysis,the present article provides,for the first time,a comprehensive summary of previous review publications that have been published since 2020,with a special focus on solid oxide materials and electrochemical ***,this study provides an important reference for researchers specializing in the fields of solid state ionics,high-temperature electrochemistry,and energyconversiontechnologies.

关键词： SOFCs SOECs PCFCS Electrochemistry Energy conversion Hydrogen energy,Carbon neutrality

Large-scale error-tolerant programmable interferometer fabricated by femtosecond laser writing

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Photonics Research 2024年第3期12卷 I0028-I0040页

作者： ILYA KONDRATYEV VERONIKA ivanova SUREN FLDZHYAN ARTEM ARGENCHIEV NIKITA KOSTYUCHENKO SERGEY ZHURAVITSKII NIKOLAY SKRYABIN IVAN DYAKONOV MIKHAIL SAYGIN STANISLAV STRAUPE ALEXANDER KORNEEV SERGEI KULIK Quantum Technology Centre and Faculty of Physics M.V.Lomonosov Moscow State UniversityMoscow 119991Russia Russian Quantum Center Moscow 121205Russia Laboratory of Quantum Engineering of Light South Ural State UniversityChelyabinsk 454080Russia

We introduce a programmable eight-port interferometer with the recently proposed error-tolerant architecture capable of performing a broad class of *** interferometer has been fabricated with femtosecond laser writing,and it is the largest programmable interferometer of this kind to *** have demonstrated its advantageous error tolerance by showing an operation in a broad wavelength range from 920 to 980 nm,which is particularly relevant for quantum photonics due to efficient photon sources existing in this wavelength *** work highlights the importance of developing novel architectures of programmable photonics for information processing.

关键词： interferometer laser femtosecond

Investigation of thermal evolution of nanodomain structures in nonlinear barium sodium niobate crystals

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Chinese Optics Letters 2008年第2期6卷 143-145页

作者： S.V.ivanova P.N.Lebedev Physical Institute of RAS Leninsky pr.53 Moscow 119991Russia

By the 90° elastic light scattering investigation and far field observation in the range of 20 - 800 ℃, the relation between behavior of light scattering anomalies and evolution of nanodomain structures in lattice of barium sodium niobate （Ba2NaNb5O15, BSN） crystal was clarified. The correlation between anomalies on the temperature curves of the elastic light scattering intensity and temperature transformations of nanodomains was studied by X-ray and electron microscope methods. Phase transition near 500 ℃ and movement in field of scattering light could be explained by appearance of a new incommensurate phase.

关键词： Elastic scattering Light fields Light intensity Light scattering Transmission electron microscopy X ray microscopy

Modelling of microbial enhanced oil recovery application using anaerobic gas-producing bacteria

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Petroleum Science 2014年第2期11卷 272-278页

作者： Pavel Spirov Yanina ivanova Svetlana Rudyk Department of Petroleum and Chemical Engineering Sultan Qaboos University Chemistry & Environment Mrsk Olie og Gas A/S Kanalen 2 DK-6700 Esbjerg

Microbial enhanced oil recovery （MEOR） methods apply injection of bacteria to depleted oil reservoirs to produce oil, which had remained unrecovered after the conventional methods of production. The ability ofthermophilic anaerobic bacteria to produce gas as the main mechanism in potential MEOR in high salinities of 70-100 g/L was investigated in this study. Maximum gas production of up to 350 mL per 700 mL of salty solution was produced at a salinity of 90 g/L stably during 2-4 days of experiment. The experimental results were upscaled to the Snorre Oilfield, Norway, and simulated using ECLIPSE software for 27 months. The best scenarios showed that the increase in oil recovery on average was at 21% and 17.8% respectively. This study demonstrated that anaerobic bacteria used in biogas plants could be an attractive candidate for MEOR implementation due to their ability to withstand high temperature and salinity, and produce gas in large volumes.

关键词： Microbiological enhanced oil recovery CO2 injection ECLIPSE simulation

Influence of agricultural development and climate changes on the drainage valley density of the southern half of the Russian Plain

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International Journal of Sediment Research 2017年第1期32卷 60-72页

作者： Valentin Golosov Nadezhda ivanova Saniya Kurbanova Kazan Federal University Lomonosov Moscow State University

The southern half of the Russian Plain is characterized by a relatively short history of intensively ploughed *** duration varies from approximately three centuries in the southern part of the forest zone to less than one century in some parts of the steppe *** was found that after cultivation,on more than 40%of lands in river basins the drainage valley density(Ddv) decreased by 15-58%in all landscape *** the first stage,the Ddvdecrease was mostly associated with increasing surface runoff coefficient after cultivation of virgin lands with proportional decreases in groundwater *** the second stage,usually after reaching areas of arable lands in river basins > 60%,the volume of eroded sediments entering small river channels exceeded the transport capacities of the permanent *** a result,the river channels completely *** later stages,the sediment redistribution cascade within the small river basins of the Russian Plain stabilized because of the increasing proportion of sediment eroded from the basin areas and re-deposited before entering the river channels because of the increasing area of sediment sinks due to the increase in dry valley lengths and total *** morphological parameters of small valleys and groundwater discharges are the key parameters that affect the intensity of small river aggradation on the regional scale.

关键词： Soil erosion Sediment redistribution Climate change Land use change European Russia

Overproduction of reactive oxygen species–obligatory or not for induction of apoptosis by anticancer drugs

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Chinese Journal of Cancer Research 2016年第4期28卷 383-396页

作者： Donika ivanova Zhivko Zhelev Ichio Aoki Rumiana Bakalova Tatsuya Higashi Medical Faculty Trakia University Institute of Biophysics & Biomedical Engineering Bulgarian Academy of Sciences Department of Molecular Imaging and Theranostics National Institute of Radiological SciencesNational Institute for Quantum and Radiological Science and Technology Medical Faculty Sofia University

Many studies demonstrate that conventional anticancer drugs elevate intracellular level of reactive oxygen species （ROS） and alter redox-homeostasis of cancer cells. It is widely accepted that anticancer effect of these chemotherapeutics is due to induction of oxidative stress and ROS-mediated apoptosis in cancer. On the other hand, the harmful side effects of conventional anticancer chemotherapy are also due to increased production of ROS and disruption of redox-homeostasis of normal cells and tissues. This article describes the mechanisms for triggering and modulation of apoptosis through ROS-dependent and ROS^independent pathways. We try to answer the question：＂Is it possible to induce highly specific apoptosis only in cancer cells, without overproduction of ROS, as well as without harmful effects on normal cells and tissues？＂ The review also suggests a new therapeutic strategy for selective killing of cancer cells, without significant impact on viability of normal cells and tissues, by combining anticancer drugs with redox-modulators, affecting specific signaling pathways and avoiding oxidative stress.

关键词： Cancer reactive oxygen species chemotherapy ROS-independent apoptosis ROS-dependent apoptosis