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Plasma Science and Technology 2020年第11期22卷 60-73页

作者： Elena KRALKINA konstantin vavilin Ilya ZADIRIEV Alexander NIKONOV Physical Electronics Department Faculty of PhysicsLomonosov Moscow State UniversityMoscow 119991Russia

The efficiency of radio-frequency(RF)power absorption,RF magnetic field structure and plasma parameters were measured in cylindrical inductive RF plasma sources 20 cm in diameter and 22,32,53 cm in length with a low value external magnetic *** experiments were carried out in argon at pressures of 13-140 m *** RF power supply changed from 200 W to 800 *** spiral antenna was used for sustaining the *** was shown that efficiency of RF power absorption depended nonlinearly on the external magnetic field *** maximal values of the RF power absorption efficiency,the axial distributions of longitudinal Bzand azimuthal Bφcomponents of RF magnetic field manifested the formation of the partially standing wave with a half wavelength close to 8 *** the same conditions,the axial dependence of the radial RF magnetic field component Brdiffered *** was concluded that the Bz and Bφamplitudes were largely determined by the RF field of Trivelpiece-Gould wave,while Br amplitude represented the radial RF field of the helicon wave.

关键词： radio-frequency plasma helicon Trivelpiece-Gould waves inductive discharge

Experimental study of a low-pressure hybrid RF discharge

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Plasma Science and Technology 2020年第5期22卷 70-82页

作者： Elena KRALKINA Polina NEKLIUDOVA Vladimir PAVLOV konstantin vavilin Ilya ZADIRIEV and Chen ZHAO Physical Electronics Department Faculty of PhysicsLomonosov Moscow State University119991 MoscowRussia

Experimental study of the low-pressure hybrid RF discharge with both inductive and capacitive channels was carried out. The RF power unit consists of inductor(antenna) and capacitor plates connected in parallel to the same RF power source. A separating capacitor Csepis included into the circuit between the antenna ends and the lead connected to the discharge capacitor plate in order to prevent the closing of the capacitive circuit through direct current by inductor and to control the contribution of capacitive channel to discharge sustaining. It is shown that at low power of the RF power source, power coupling to the discharge mainly occurs through the capacitive channel. Increasing the power of the RF power source increases the power coupled in the inductive channel, electron density, and current flowing through the capacitive channel. This leads to increasing voltage drop on the separating capacitor and partial cutoff of the capacitive channel. At separating capacitance values below certain value(below 50 pF in the present experiments), the self-bias of the loaded plate of the discharge capacitor becomes positive indicating that the thickness of the electrode sheath of the loaded electrode decreases compared to thickness of the sheath of the grounded electrode. The thickness of the space-charge sheath of the grounded electrode decreases with increasing power coupled to the plasma. At separating capacitance below 50 pF, higher harmonics of the RF voltage and current are actively generated in the capacitive discharge channel. Increasing the separating capacitance leads to decreasing electron density, increasing effective electron temperature and more effective RF energy coupling to plasma due to increasing relative importance of the capacitive discharge channel.

关键词： radio-frequency discharge plasma E-mode H-mode

Plasma treatment for enhancement of the sorption capacity of carbon fabric

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Plasma Science and Technology 2021年第12期23卷 150-160页

作者： IIya ZADIRIEV Elena KRALKINA Vladimir SAMOILOV Victoria ELCHANINOVA Valentina GORINA Ilya IVANENKO konstantin vavilin Alexander NIKONOV Physical Electronics Department Faculty of PhysicsLomonosov Moscow State University119991 MoscowRussia Research Institute for Graphite-Based Structural Materials‘Nllgrafit’ 1524 MoscowRussia

In this work we carried out an experimental investigation into enhancement of the sorption capacity of carbon fabric using plasma treatment *** fabric is based on viscose fiber and is hydrophobic by *** of the fabric sorption capacity is required for its application in *** this purpose,two plasma treatment methods were considered,*** nonequilibrium radiofrequency(RF)discharge and a vacuum RF plasma source with an external magnetic *** treated by atmospheric discharge demonstrated aging effects during the first week after *** sorption capacity of samples treated by the RF plasma source was stable over the same period and reached values as high as *** of the beam created by the vacuum RF plasma source were analyzed and dependences of the fabric sorption capacity and specific surface area on plasma treatment time were *** found that sorption capacity reached its maximum value after 30 min of treatment and did not change significantly if processing was continued,while the specific surface area reached its maximum after 3 min of treatment and quickly decreased after *** was found that the micropore structure of the fabric remained almost the same during plasma *** volume of mesopores in a unit of the fabric mass(specific volume)doubled during the first 5 min of treatment and returned to initial values after 30 min of *** sorption capacity continued to increase even when the specific surface area decreased after reaching its peak *** indicates the important role of surface functional groups formed on carbon fibers during plasma *** is consistent with the results of x-ray photoelectron spectroscopy analysis showing changes in surface oxidation during plasma treatment.

关键词： carbon fabric sorption plasma treatment radiofrequency

Comparison of pulse-modulated and continuous operation modes of a radio-frequency inductive ion source

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Plasma Science and Technology 2023年第2期25卷 131-145页

作者： Ilya ZADIRIEV Elena KRALKINA konstantin vavilin Alexander NIKONOV Georgy SHVIDKIY Physical Electronics Department Faculty of PhysicsLomonosov Moscow State UniversityMoscow 119991Russia

The paper describes an experimental study of the characteristics of a pulse-modulated radiofrequency(RF)discharge sustained at low pressures,typical of the operating modes of RF gridded ion *** motivation for the study is the question of whether the RF pulsemodulated mode can increase the efficiency of the ion *** ion current values extracted from an RF inductive ion source operating in continuous and pulse-modulated modes were *** experimental data were also compared with the parameter calculations based on a0D numerical model of the *** measurements showed that the pulse-modulated operation mode of the RF ion source had a noticeable advantage when the power of the RF generator was 140 W or ***,as the generator power increased,the advantage was lost because the pulse-modulated operation mode,having a higher RF power instant value,entered the region of existence sooner than the continuous mode,where the ion production cost begins to grow with RF power.

关键词： discharge plasma radio frequency(RF) pulse electrons ions

Actuality and underlying mechanisms of systemic immuneinflammation index and geriatric nutritional risk index prognostic value in hepatocellular carcinoma

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World Journal of Gastrointestinal Surgery 2024年第2期16卷 260-265页

作者： konstantin Y Tchilikidi Department of Surgery with Postgraduate Education Altai State Medical UniversityBarnaul 656031Russia

This editorial contains comments on the article“Correlation between preoperative systemic immune inflammation index,nutritional risk index,and prognosis of radical resection of liver cancer”in a recent issue of the World Journal of Gastrointestinal *** pointed out the actuality and importance of the article and focused primarily on the underlying mechanisms making the systemic immuneinflammation index(SII)and geriatric nutritional risk index(GNRI)prediction features *** are few publications on both SII and GNRI together in hepatocellular carcinoma(HCC)and patient prognosis after radical *** release cytokines,chemokines,and enzymes,degrade extracellular matrix,reduce cell adhesion,and create conditions for tumor cell *** promote the adhesion of tumor cells to endothelial cells,through physical *** results in the migration of tumor ***-angiogenic factors from platelets enhance tumor angiogenesis to meet tumor cell supply *** can form a protective film on the surface of tumor *** allows avoiding blood flow damage as well as immune system *** also induces the epithelial-mesenchymal transformation of tumor cells that is critical for *** SII is also associated with macro-and microvascular invasion and increased numbers of circulating tumor cells.A high GNRI was associated with significantly better progression-free and overall *** patients are a very special population that requires increased *** and GNRI have significant survival prediction value in both palliative treatment and radical surgery *** underlying mechanisms of their possible predictive properties lie in the field of essential cancer *** features provide tumor nutrition,growth,and distribution throughout the body,such as vascular *** the other hand,they are tied to the possibility of patients to resist tumor progression and development of complications in bot

关键词： Systemic immune-inflammation index Geriatric nutritional risk index Radical surgery Transarterial chemoembolization Hepatocellular carcinoma Prognosis

Ex vivo liver resection and auto-transplantation and special systemic therapy in perihilar cholangiocarcinoma treatment

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World Journal of Gastrointestinal Surgery 2024年第3期16卷 635-640页

作者： konstantin Y Tchilikidi Department of Surgery with Postgraduate Education Altai State Medical UniversityBarnaul 656031Russia

This editorial contains comments on the article“Systematic sequential therapy for ex vivo liver resection and autotransplantation:A case report and review of li-terature”in the recent issue of World Journal of Gastrointestinal *** points out the actuality and importance of the article and focuses primarily on the role and place of ex vivo liver resection and autotransplantation(ELRAT)and systemic therapy,underlying molecular mechanisms for targeted therapy in perihilar cho-langiocarcinoma(pCCA)*** is a tough malignancy with a high proportion of advanced disease at the time of *** only curative option is radical *** excision and reconstruction become extremely com-plicated and not always could be performed even in localized *** the other hand,ELRAT takes its place among surgical options for carefully selected pCCA *** advanced disease,systemic therapy becomes a viable option to prolong *** editorial describes current possibilities in chemotherapy and reveals underlying mechanisms and projections in targeted therapy with ki-nase inhibitors and immunotherapy in both palliative and adjuvant ***-broblast grow factor and fibroblast grow factor receptor,human epidermal grow-th factor receptor 2,isocitrate dehydrogenase,and protein kinase cAMP activated catalytic subunit alpha(PRKACA)and beta(PRKACB)pathways have been ac-tively investigated in CCA in last *** agents were introduced and approved by the Food and Drug *** all demonstrated mean-ingful activity in CCA patients with no global change in *** is why every successfully treated patient counts,especially those with advanced *** conclusion,pCCA is still hard to treat due to late diagnosis and extremely complicated surgical *** also brings some hope,but it could be performed in very carefully selected *** disease requires systemic anticancer treatment,which is supposed to be indivi

关键词： Perihilar cholangiocarcinoma Klatskin’tumor Ex vivo liver resection and autotransplantation Chemotherapy Immunotherapy Targeted therapy

The Disintegration of a Floating Ferrofluid Layer into an Ordered Drop System in a Vertical Magnetic Field

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Fluid Dynamics & Materials Processing 2024年第10期20卷 2205-2218页

作者： Christina Khokhryakova konstantin Kostarev Irina Mizeva Laboratory of Dispersed System Dynamics Institute of Continuous Media Mechanics UrB RASPerm614018Russia Laboratory of Hydrodynamical Stability Institute of Continuous Media Mechanics UrB RASPerm614018Russia Laboratory of Turbulence Institute of Continuous Media Mechanics UrB RASPerm614018Russia

Magnetic fluids,also known as ferrofluids,are versatile functional materials with a wide range of *** applications span from industrial uses such as vacuum seals,actuators,and acoustic devices to medical uses,including serving as contrast agents for magnetic resonance imaging(MRI),delivering medications to specific locations within the body,and magnetic hyperthermia for cancer *** use of a non-wettable immiscible liquid substrate to support a layer of magnetic fluid opens up new possibilities for studying various fluid flows and related instabilities in multi-phase systems with both a free surface and an *** presence of two deformable boundaries within a ferrofluid layer significantly reduces the critical magnetic field strength required to transform the layer into an organized system of drops or polygonal figures evolving according to the intensity,frequency and direction of the considered magnetic *** paper experimentally investigates this problem by assuming a uniform magnetic field perpendicular to the *** specific subject has not been previously explored *** critical magnetic field intensity required to destabilize the ferrofluid layer is determined based on the layer’s thickness and the fluid’s initial magnetic *** is demonstrated that the critical magnetic field strength needed to disrupt the initially continuous ferrofluid layer increases with the layer’s ***,an increase in the ferrofluid’s magnetic susceptibility results in a decrease in the critical magnetic field *** emerging droplet structures are analyzed in terms of the number of drops,their size,and the periodicity of their *** number of droplets formed depends on the initial thickness of the layer,the presence or absence of a stable rupture in the upper layer,and the rate at which the magnetic field strength is increased to the critical value.A characteristic viscous time is proposed

关键词： Ferrofluid liquid substrate normal field instability ordered droplet structure

Robotic surgery in living liver donors and liver recipients

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Laparoscopic, Endoscopic and Robotic Surgery 2024年第3期7卷 123-127页

作者： konstantin Semash Department of Mini-Invasive Surgery National Children’s Medical CenterTashkent 100171Uzbekistan

There have been nearly 60 years since Thomas Starzl’s first liver *** this period,advancements in medical technology have progressively enabled the adoption of new methods for *** these innovations,robotic surgery has emerged in recent decades and is gradually being integrated into transplant *** hepatectomy and liver implantation represent significant advancements in the field of transplant *** precision and minimally invasive nature of robotic surgery offer substantial benefits for both living donors and *** living donors,robotic hepatectomy reduces postoperative pain,minimizes scarring,and accelerates *** liver recipients,robotic liver implantation enhances surgical accuracy,leading to better graft positioning and vascular *** systems provide more precise and maneuverable control of instruments,allowing surgeons to perform complex procedures with greater accuracy and reduced risk to *** review encompasses publications on minimally invasive donor liver surgery,with a specific focus on robotic liver resection in transplantation,and aims to summarize current knowledge and the development status of robotic surgery in liver transplantation,focusing on liver resection in donors and graft implantation in recipients.

关键词： Liver transplantation Robotic surgery Robotic liver resection Robotic hepatectomy Robotic liver implantation

Consideration of the influence of supports in modeling the electromagnetic fields of 25 kV traction networks under emergency conditions

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Global Energy Interconnection 2024年第4期7卷 528-540页

作者： konstantin Suslov Andrey Kryukov Ekaterina Voronina Pavel Ilyushin Department of Hydropower and Renewable Energy National Research UniversityMoscow Power Engineering InstituteMoscow 11250Russia Department of Power Supply and Electrical Engineering Irkutsk National Research Technical UniversityIrkutsk 664074Russia Department of Transport Electric Power Irkutsk State Transport UniversityIrkutsk 664074Russia Department of Research on the Relationship between Energy and the Economy Energy Research Institute of the Russian Academy of SciencesMoscow 117186Russia

Single-phase 25 kV traction networks of electrified alternating current(AC)railways create electromagnetic fields(EMFs)with significant levels of *** most intense magnetic fields occur when short circuits exist between the contact wire and rails or *** the short duration of exposure,they can adversely affect electronic devices and induce significant voltages in adjacent power lines,which is dangerous for operating *** numerous investigations have focused on modeling the EMF of traction networks and power lines,the challenge of determining the three-dimensional electromagnetic fields near metal supports during the flow of a short-circuit current through them is yet to be *** this case,the field has a complex spatial structure that significantly complicates the calculations of *** study proposes a methodology,algorithms,software,and digital models for determining the EMF in the described emergency *** the modeling process,the objects being studied were represented by segments of thin wires to analyze the distribution of the electric charge and calculate the intensities of the electric and magnetic *** approach was implemented in the Fazonord software,and the modeling results show a substantial increase in EMF levels close to the support,with a noticeable decrease in the levels as the distance from it *** procedure implemented in the commercial software Fazonord is universal and can be used to determine electromagnetic fields at any electrical power facility that includes live parts of limited *** on the proposed procedure,the EMF near the supports of overhead power lines and traction networks of various designs could be determined,the EMF levels at substations can be calculated,and the influence of metal structures located near traction networks,such as pedestrian crossings at railway stations,can be considered.

关键词： Power supply systems AC railways Emergency conditions Electromagnetic fields near supports Modeling Electromagnetic safety

Electroluminescence from pure resonant states in hBN-based vertical tunneling junctions

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Light(Science & Applications) 2024年第8期13卷 1557-1564页

作者： Magdalena Grzeszczyk Kristina Vaklinova Kenji Watanabe Takashi Taniguchi konstantin SNovoselov Maciej Koperski Institute for Functional Intelligent Materials National University of SingaporeSingapore 117544Singapore Research Center for Functional Materials National Institute for Materials ScienceTsukuba 305-0044Japan International Center for Materials Nanoarchitectonics National Institute for Materials ScienceTsukuba 305-0044Japan Department of Materials Science and Engineering National University of SingaporeSingapore 117575Singapore

Defect centers in wide-band-gap crystals have garnered interest for their potential in applications among optoelectronic and sensor ***,defects embedded in highly insulating crystals,like diamond,silicon carbide,or aluminum oxide,have been notoriously difficult to excite electrically due to their large internal *** address this challenge,we realized a new paradigm of exciting defects in vertical tunneling junctions based on carbon centers in hexagonal boron nitride(hBN).The rational design of the devices via van der Waals technology enabled us to raise and control optical processes related to defect-to-band and intradefect *** fundamental understanding of the tunneling events was based on the transfer of the electronic wave function amplitude between resonant defect states in hBN to the metallic state in graphene,which leads to dramatic changes in the characteristics of electrons due to different band structures of constituent *** our devices,the decay of electrons via tunneling pathways competed with radiative recombination,resulting in an unprecedented degree of tuneability of carrier dynamics due to the significant sensitivity of the characteristic tunneling times on the thickness and structure of the *** enabled us to achieve a high-efficiency electrical excitation of intradefect transitions,exceeding by several orders of magnitude the efficiency of optical excitation in the sub-band-gap *** work represents a significant advancement towards a universal and scalable platform for electrically driven devices utilizing defect centers in wide-band-gap crystals with properties modulated via activation of different tunneling mechanisms at a level of device engineering.

关键词： carbide tunneling defect