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The influence of composition of asphaltenes of different genesis on the properties of carbon materials manufactured from them by plasma processing

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Petroleum Science 2023年第6期20卷 3830-3840页

作者： Evgeniya Frantsina Yuliya Petrova Valentina Arkachenkova Andrey Grin'ko Alexander Pak pavel povalyaev Dmitry Zelentsov Kirill Cherednichenko Surgut State University Institute of Natural and Technical Sciencespr.Lenina 1628412SurgutRussian Federation Tomsk Polytechnic University Laboratory of Advanced Materials for the Energy Industrypr.Lenina30643050TomskRussian Federation National University of Oil and Gas Gubkin University Department of Physical and Colloidal Chemistrypr.Lenina65119991MoscowRussian Federation

The results of experimental studies of carbon materials, which are formed in the plasma of a direct current (DC) arc discharge initiated in open air from the asphaltenes of different origins, extracted from the natural asphaltite and from the oil of the Sredne-Ugutskoye Oilfield, are presented. The influence of the initial asphaltene composition on the composition and properties of the resulting carbon materials is analyzed. The initial asphaltenes and the samples of the carbon materials are characterized by the methods of X-ray diffraction, differential thermal analysis, X-ray fluorescence analysis, IR-Fourier spectroscopy, laser diffraction, transmission and scanning electron microscopy. The changes in the composition and structure of the asphaltenes are determined before and after their plasma treatment and the hypotheses are put forward concerning the chemical processes causing the changes in the molecular structure of the samples. As a result of plasma treatment of asphaltenes (100 A, 30 s), it was shown that graphitization occurs, as well as oxidation, and a decrease in sulfur content. Moreover, nanotubes and nano-onions have been detected using electron microscopy. Petroleum asphaltenes after plasma treatment give a less thermostable carbon material, but with a lower content of heteroatoms, and with a large amount of sulfur in the composition of sulfoxide structural fragments. This method is shown to be a promising technology for processing the petroleum feedstock enriched with heavy asphaltene components for the manufacture of carbon nanomaterials: nanotubes, nano-onions and polyhedral graphite.

关键词： Asphaltenes Natural asphaltite Carbon materials Nanomaterials Plasma treatment Graphite

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Architecture of Graphics System with 3D Acceleration Support for Embedded Operating Systems

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Tsinghua Science and Technology 2024年第3期29卷 863-873页

作者： Alexander Giatsintov Kirill Mamrosenko pavel Bazhenov Center of Visualization and Sattelite Information Technologies Scientific Research Institute for System Analysis of the Russian Academy of Sciences(SRISA RAS)Moscow 117218Russia

An increasing number of tasks now require the use of hardware accelerators to reduce the time required for computation and display the computational results.This paper presents a new graphics system architecture for operating systems(OSs)with microkernel architecture,including real-time OSs.The proposed system architecture provides capabilities for displaying graphical images on various information display devices and for accelerating graphical operations on GPU.The architecture of the graphics system uses a concept of allocators to manage system and video memory,provides an abstraction of memory operations with a single interface for video memory management,and simplifies memory handling where incorrect operation is the cause of many failures.A comparison between the performance of a real-time OS and Linux OS implementing the graphics system using the example of a glmark2 benchmark is presented,thereby the superiority of the proposed architecture in several scenarios is demonstrated.

关键词： real-time operating system(RTOS) graphics system rendering system architecture operatingsystem visualization system programming

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Thermogravimetric,kinetic study and gas emissions analysis of the thermal decomposition of waste-derived fuels

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Journal of Environmental Sciences 2024年第3期137卷 155-171页

作者： Vadim V.Dorokhov Galina S.Nyashina pavel A.Strizhak Heat and Mass Transfer Laboratory National Research Tomsk Polytechnic University30 Lenin AvenueTomsk 634050Russia

A wide range of wastes can potentially be used to generate thermal and electrical energy.The co-combustion of several types of waste as part of water-containing waste-derived fuels is a promising method for their recovery.In this research,we use thermogravimetric analysis and differential scanning calorimetry to study the thermal behavior and kinetics of coal slime,biomass,waste oils,and blends on their basis.We also analyze the concentrations of gaseous emissions.The results show that biomass,oils,and coal slime significantly affect each other in the course of their co-combustion when added to slurry fuels.The preparation of coal-water slurry based on slime and water reduced the ignition and burnout temperature by up to 16%.Adding biomass and waste oils additionally stimulated the slurry ignition and burnout,which occurred at lower temperatures.Relative to dry coal slime,threshold ignition temperatures and burnout temperatures decreased by 6%–9%and 17%–25%,respectively.Also,the use of biomass and waste oils as part of slurries inhibited NOхand SO_(2)emission by 2.75 times.According to the kinetic analysis,added biomass and waste turbine oil provide a 28%–51%reduction in the activation energy as compared to a coal-water slurry without additives.

关键词： Coal-water slurry Water-containing composite fuels Combustion Emission Kinetic TGA-DSC

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Pulsed THz radiation under ultrafast optical discharge of vacuum photodiode

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Frontiers of Optoelectronics 2024年第2期17卷 99-112页

作者： Aleksandr Ushakov Kseniia Mamaeva Leonid Seleznev Georgy Rizaev Vladimir Bukin Timophey Dolmatov pavel Chizhov Vladimir Bagdasarov Sergey Garnov Prokhorov General Physics Institute of the Russian Academy of Sciences Moscow 119991Russia Physical Institute Russian Academy of SciencesMoscow 119991Russia Moscow Institute of Physics and Technology Dolgoprudny 141700Russia Russian Institute for Scientific and Technical Information Moscow 125190Russia

In this paper,we first present an experimental demonstration of terahertz radiation pulse generation with energy up to 5 pJ under the electron emission during ultrafast optical discharge of a vacuum photodiode.We use a femtosecond optical excitation of metallic copper photocathode for the generation of ultrashort electron bunch and up to 45 kV/cm external electric field for the photo-emitted electron acceleration.Measurements of terahertz pulses energy as a function of emitted charge density,incidence angle of optical radiation and applied electric field have been provided.Spectral and polarization characteristics of generated terahertz pulses have also been studied.The proposed semi-analytical model and simulations in COMSOL Multiphysics prove the experimental data and allow for the optimization of experimental conditions aimed at flexible control of radiation parameters.

关键词： Electron emission Vacuum photodiode Ultrafast excitation Terahertz

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Diamond-Like Carbon Depositing on the Surface of Polylactide Membrane for Prevention of Adhesion Formation During Tendon Repair

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Nano-Micro Letters 2024年第9期16卷 478-499页

作者： Yao Xiao Zaijin Tao Yufeng Ju Xiaolu Huang Xinshu Zhang Xiaonan Liu pavel A.Volotovski Chao Huang Hongqi Chen Yaozhong Zhang Shen Liu Department of Orthopaedics Shanghai Jiao Tong University School of Medicine Affiliated Sixth People’s Hospital600 Yishan RdShanghai 200233People’s Republic of China Shanghai Tongji Hospital 389 Xincun RdShanghai 200065People’s Republic of China Key Laboratory for Thin Film and Microfabrication of Ministry of Education Research Institute of Micro/Nano Science and TechnologyShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China Orthopedic Trauma Department Belarus Republic Scientific and Practical Center for Traumatology and OrthopedicsKizhevatova str.60/4220024 MinskBelarus Shanghai Haohai Biological Technology Limited Liability Company 1386 Hongqiao RdShanghai 200336People’s Republic of China Department of General Surgery Shanghai Jiao Tong University School of Medicine Affiliated Sixth People’s Hospital600 Yishan RdShanghai 200233People’s Republic of China Shanghai Key Laboratory for High Temperature Materials and Precision Forming School of Materials Science and EngineeringShanghai Jiao Tong UniversityShanghai 200240People’s Republic of China

Post-traumatic peritendinous adhesion presents a significant challenge in clinical medicine.This study proposes the use of diamond-like carbon(DLC)deposited on polylactic acid(PLA)membranes as a biophysical mechanism for anti-adhesion barrier to encase ruptured tendons in tendon-injured rats.The results indicate that PLA/DLC composite membrane exhibits more efficient anti-adhesion effect than PLA membrane,with histological score decreasing from 3.12±0.27 to 2.20±0.22 and anti-adhesion effectiveness increasing from 21.61%to 44.72%.Mechanistically,the abundant C=O bond functional groups on the surface of DLC can reduce reactive oxygen species level effectively;thus,the phosphorylation of NF-κB and M1 polarization of macrophages are inhibited.Consequently,excessive inflammatory response augmented by M1 macrophage-originated cytokines including interleukin-6(IL-6),interleukin-1β(IL-1β),and tumor necrosis factor-α(TNF-α)is largely reduced.For biocompatibility evaluation,PLA/DLC membrane is slowly absorbed within tissue and displays prolonged barrier effects compared to traditional PLA membranes.Further studies show the DLC depositing decelerates the release of degradation product lactic acid and its induction of macrophage M2 polarization by interfering esterase and PLA ester bonds,which further delays the fibrosis process.It was found that the PLA/DLC membrane possess an efficient biophysical mechanism for treatment of peritendinous adhesion.

关键词： Diamond-like carbon Reactive oxygen species scavenging Foreign body reaction Biodegradation Antioxidant Peritendinous adhesion

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Resonantly enhanced second-and third-harmonic generation in dielectric nonlinear metasurfaces

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Opto-Electronic Advances 2024年第5期7卷 8-23页

作者： Ji Tong Wang pavel Tonkaev Kirill Koshelev Fangxing Lai Sergey Kruk Qinghai Song Yuri Kivshar Nicolae C.Panoiu Department of Electronic and Electrical Engineering University College London Nonlinear Physics Center Research School of PhysicsAustralian National University Ministry of Industry and Information Technology Key Lab of Micro-Nano Optoelectronic Information System Guangdong Provincial Key Laboratory of Semiconductor Optoelectronic Materials and Intelligent Photonic SystemsHarbin Institute of Technology Wuzhen Laboratory EGO Wuzhen Digital Economy Industrial Park

Nonlinear dielectric metasurfaces provide a promising approach to control and manipulate frequency conversion optical processes at the nanoscale,thus facilitating both advances in fundamental research and the development of new practical applications in photonics,lasing,and sensing.Here,we employ symmetry-broken metasurfaces made of centrosymmetric amorphous silicon for resonantly enhanced second-and third-order nonlinear optical response.Exploiting the rich physics of optical quasi-bound states in the continuum and guided mode resonances,we comprehensively study through rigorous numerical calculations the relative contribution of surface and bulk effects to second-harmonic generation(SHG)and the bulk contribution to third-harmonic generation(THG) from the meta-atoms.Next,we experimentally achieve optical resonances with high quality factors,which greatly boosts light-matter interaction,resulting in about 550 times SHG enhancement and nearly 5000-fold increase of THG.A good agreement between theoretical predictions and experimental measurements is observed.To gain deeper insights into the physics of the investigated nonlinear optical processes,we further numerically study the relation between nonlinear emission and the structural asymmetry of the metasurface and reveal that the generated harmonic signals arising from linear sharp resonances are highly dependent on the asymmetry of the meta-atoms.Our work suggests a fruitful strategy to enhance the harmonic generation and effectively control different orders of harmonics in all-dielectric metasurfaces,enabling the development of efficient active photonic nanodevices.

关键词： all-dielectric metasurfaces bound state in the continuum guided mode resonance nonlinear optics second-harmonic generation third-harmonic generation

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Independent control of circularly polarized light with exceptional topological phase coding metasurfaces

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Photonics Research 2024年第3期12卷 534-542页

作者： YICHENG LI SHICHENG WAN SHAOXUAN DENG ZHENGWEI DENG BO LV CHUNYING GUAN JUN YANG ANDREY BOGDANOV pavel BELOV JINHUI SHI Key Laboratory of Photonic Materials and Devices Physics for Oceanic Applications Ministry of Industry and Information TechnologyCollege of Physics and Optoelectronic EngineeringHarbin Engineering UniversityHarbin 150001China Key Laboratory of In-Fiber Integrated Optics of Ministry of Education College of Physics and Optoelectronic EngineeringHarbin Engineering UniversityHarbin 150001China School of Physics and Engineering ITMO UniversitySt.Petersburg 197101Russia School of Information Engineering Guangdong University of TechnologyGuangzhou 510008China Qingdao Innovation and Development Center Harbin Engineering UniversityQingdao 266000China

Exceptional points,as degenerate points of non-Hermitian parity-time symmetric systems,have many unique physical properties.Due to its flexible control of electromagnetic waves,a metasurface is frequently used in the field of nanophotonics.In this work,we developed a parity-time symmetric metasurface and implemented the 2πtopological phase surrounding an exceptional point.Compared with Pancharatnam-Berry phase,the topological phase around an exceptional point can achieve independent regulation of several circular polarization beams.We combined the Pancharatnam-Berry phase with the exceptional topological phase and proposed a composite coding metasurface to achieve reflection decoupling of different circular polarizations.This work provides a design idea for polarimetric coding metasurfaces in the future.

关键词： properties. exceptional topological

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Pyroelectric Plate with Magnetoelectric Effect

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Journal of Applied Mathematics and Physics 2024年第5期12卷 1616-1625页

作者： pavel Grinfeld Michael Grinfeld Mathematics Department Drexel University Philadelphia USA The U.S. Army Research Laboratory WMRD Aberdeen Proving Ground USA

In dynamic problems the electric and magnetic fields are inseparable. At the same time, a multitude of electrostatic and magnetostatic effects permit mutually independent description. This separation appears to be possible and thermodynamically consistent when the bulk energy density depends only on the polarization density or, alternatively, on the magnetization density. However, when the bulk energy density depends simultaneously on the both densities, then, the electrostatic and magnetostatic effects should be studied together. There appear interesting cross-effects;among those are the change of the internal electrostatic field inside a specimen under the influence of the external magnetic fields, and vice versa. Below, in the framework of thermodynamic approach the boundary value problem for magnetoelectric plate is formulated and analyzed. The exact solution is established for the isotropic pyroelectric plate.

关键词： Electricity and Magnetism Pyroelectrics and Pyromagnetics Thermodynamics of Electromagnetostatics Exact Solutions Validation and Verification

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A novel dual-core fiber-optic gyroscope with independent rotation rate measurements in different cores of a dual-core optical fiber

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Optoelectronics Letters 2024年

作者： EMIL A.MILIKOV VIACHESLAV V.ZEMLYAKOV pavel S.ANISIMOV GAO Jiexing 2012 Labs Central Research Institute Huawei Technologies Co. Ltd.

We introduce an all-fiber stationary phase shifter for a fiber-optic gyroscope which simultaneously provides phase shifts of opposite signs in different cores of the dual-core optical fiber. We propose a new dual-core fiber-optic gyroscope in which different cores of the dual-core optical fiber provide independent rotation rate measurements. The device enables implementation of a differential scheme， which ensures the stability of the measured phase shift. As a computer simulations result， the accuracy of the rotation rate sensing increased by up to 10 times at typical noise levels.

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Artificial enhancement of sturgeon stock in freshwater reservoirs:A case study on sterlet Acipenser ruthenus of the Kama reservoir

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Aquaculture and Fisheries 2024年第2期9卷 287-294页

作者： pavel B.Mikheev Semyon N.Kazarinov Alla G.Melnikova Stanislav V.Ponosov Nikolai G.Petrenko Andrei I.Nikiforov Alexey Yu Puzik Olga N.Elchenkova Perm State National Research University Perm614990Russia Khabarovsk Branch of the Federal State Budget Scientific Institution“Russian Federal Research Institute of Fisheries and Oceanography”“KhabarovskNIRO” Khabarovsk680038Russia Perm Branch of the Federal State Budget Scientific Institution“Russian Federal Research Institute of Fisheries and Oceanography”“PermNIRO” Perm614991Russia Federal State Budget Scientific Institution“Russian Federal Research Institute of Fisheries and Oceanography”“VNIRO” Moscow117454Russia Moscow State Institute of International Relations(University)of the Ministry for Foreign Affairs of Russia“MGIMO” Moscow117454Russia Department of State Control Supervision and Protection of Aquatic Biological Resources for Perm KraiMiddle-Volga Regional Office of the Federal Fishery AgencyPerm614990Russia

The paper presents the results of the sterlet sturgeon Acipenser ruthenus reintroduction into the Kama Reservoir(Perm Krai,Russia)by sterlet fry from hatcheries into the reservoir since 2001.The effectiveness of hatchery releases was evaluated by monitoring gillnet sampling 2014-2020.The results showed that the species was reported throughout entire Kama Reservoir,which contrasts with 1988-1994 data,when the species was registered only at the upper part of the reservoir near the Kama River mouth.The highest number and biomass values of catch per unit effort(CPUE)of the sterlet were found in submerged river channels-the deepest habitats with flow conditions which are close to the ecological requirements of the species.The distribution of the sterlet within the channel biotopes of the reservoir is defined by reduced variability.The biggest individuals and the widest size range of the sterlet were typical for the upper area of the reservoir and Chusovskoy Bay,which have the greatest flow.The smallest sizes were typical for fish from catches near the dam of the reservoir,which is consistent with the published data on the distribution of sterlet in reservoir conditions.The presented results may indicate the artificial formation of the sterlet stock in the Kama Reservoir maintained by hatchery releases.The revealed distribution of the sterlet in the reservoir determines the direction of further research on natural reproduction and thus formation of an artificially formed population.Also,future studies are required to assess the possibility of hybridization of the sterlet of artificial origin with natural populations of the species,since the low genetic diversity of the sterlet released into the Kama Reservoir which can lead to irreversible loss of genetic individuality of the natural stocks of the species in the catchment of upper course of the Kama River.

关键词： Sterlet Acipenser ruthenus Kama reservoir Hatchery releases CPUE Artificial stock formation

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