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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

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

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

Large-for-size syndrome prophylaxis in infant liver recipients with low body mass

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World Journal of Transplantation 2025年第1期15卷 72-85页

作者： konstantin Semash Timur Dzhanbekov Department of Mini-Invasive Surgery National Children's Medical CenterTashkent 100171ToshkentUzbekistan

Transplantation of the left lateral section(LLS)of the liver is now an established practice for treating advanced diffuse and unresectable focal liver diseases in children,with variants of the LLS primarily used in ***,the surgical challenge of matching the size of an adult donor's graft to the volume of a child's abdomen remains *** review explores historical developments,various approaches to measuring the required functional liver mass,and techniques to prevent complications associated with large-for-size grafts in infants.

关键词： Pediatric liver transplantation Large-for-size syndrome Preoperative evaluation of donor and recipient Liver volumetry Monosegmental transplantation Left lateral sector graft Reduced size liver graft Abdominal wall reconstruction Liver transplantation Liver resection

Novel Methodologies for Preventing Crack Propagation in Steel Gas Pipelines Considering the Temperature Effect

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Structural Durability & Health Monitoring 2025年第1期19卷 1-23页

作者： Nurlan Zhangabay Ulzhan Ibraimova Marco Bonopera Ulanbator Suleimenov konstantin Avramov Maryna Chernobryvko Aigerim Yessengali Department of Architecture and Urban Planning Mukhtar Auezov South Kazakhstan UniversityShymkent160012Kazakhstan Department of Industrial Civil and Road Construction Mukhtar Auezov South Kazakhstan UniversityShymkent160012Kazakhstan Mechanics Sound&Vibration LaboratoryDepartment of Civil EngineeringCollege of EngineeringNational Taiwan UniversityTaipei10617Taiwan Department of Reability&Dynamic Strength A.Pidhornyi Institute of Mechanical Engineering Problems of National Academy of Sciences of UkraineKharkiv61046Ukraine

Using the software ANSYS-19.2/Explicit Dynamics,this study performedﬁnite-element modeling of the large-diameter steel pipeline cross-section for the Beineu-Bozoy-Shymkent gas pipeline with a non-through straight crack,strengthened by steel wire *** effects of the thread tensile force of the steel winding in the form of single rings at the crack edges and the wires with different winding diameters and pitches were also *** results showed that the strengthening was preferably executed at a minimum value of the thread tensile force,which was 6.4%more effective than that at its maximum *** analysis of the inﬂuence of the winding dia-meters showed that the equivalent stresses increased by 32%from the beginning of the crack growth until the wire *** increment in winding diameter decelerated the disclosure of the edge crack and reduced its length by 8.2%.The analysis of the inﬂuence of the winding pitch showed that decreasing the distance between the winding turns also led to a 33.6%reduction in the length of the straight crack and a 7.9%reduction in the maximum stres-ses on the strengthened pipeline *** analysis of the temperature effect on the pipeline material,within a range from-40℃ to+50℃,resulted in a crack length change of up to 5.8%.As the temperature dropped,the crack length *** such a temperature range,the maximum stresses were observed along the cen-tral area of the crack,which were equal to 413 MPa at+50℃ and 440 MPa at-40℃.The results also showed that the presence of the steel winding in the pipeline signiﬁcantly reduced the length of crack propagation up to 8.4 times,depending on the temperature effect and design parameters of *** work integrated the existing methods for crack localization along steel gas pipelines.

关键词： Crack propagation ﬁnite-element internal pressure prestressing steel gas pipeline temperature effect

A functional tacrolimus-releasing nerve wrap for enhancing nerve regeneration following surgical nerve repair

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Neural Regeneration Research 2025年第1期20卷 291-304页

作者： Simeon C.Daeschler Katelyn J.W.So konstantin Feinberg Marina Manoraj Jenny Cheung Jennifer Zhang Kaveh Mirmoeini JPaul Santerre Tessa Gordon Gregory HBorschel SickKids Research Institute Neuroscience and Mental Health ProgramTorontoONCanada Institute of Biomaterials and Biomedical Engineering University of TorontoTorontoONCanada Indiana University School of Medicine IndianapolisINUSA Division of Plastic and Reconstructive Surgery the Hospital for Sick ChildrenTorontoONCanada Translational Biology and Engineering Program Ted Rogers Centre for Heart ResearchInstitute of Biomedical EngineeringFaculty of DentistryUniversity of TorontoTorontoONCanada

Axonal regeneration following surgical nerve repair is slow and often incomplete,resulting in poor functional recovery which sometimes contributes to lifelong ***,there are no FDA-approved therapies available to promote nerve *** accelerates axonal regeneration,but systemic side effects presently outweigh its potential benefits for peripheral nerve *** authors describe herein a biodegradable polyurethane-based drug delivery system for the sustained local release of tacrolimus at the nerve repair site,with suitable properties for scalable production and clinical application,aiming to promote nerve regeneration and functional recovery with minimal systemic drug *** is encapsulated into co-axially electrospun polycarbonate-urethane nanofibers to generate an implantable nerve wrap that releases therapeutic doses of bioactive tacrolimus over 31 *** and drug loading are adjustable for applications in small and large caliber nerves,and the wrap degrades within 120 days into biocompatible *** released from the nerve wrap promotes axon elongation in vitro and accelerates nerve regeneration and functional recovery in preclinical nerve repair models while off-target systemic drug exposure is reduced by 80%compared with systemic *** its surgical suitability and preclinical efficacy and safety,this system may provide a readily translatable approach to support axonal regeneration and recovery in patients undergoing nerve surgery.

关键词： biodegradable local drug delivery nerve injury nerve regeneration nerve wrap tacrolimus

Modern developments related to nanotechnology and nanoengineering of concrete

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Frontiers of Structural and Civil Engineering 2016年第2期10卷 131-141页

作者： konstantin SOBOLEV Department of Civil and Environmental Engineering University of gqsconsin-Milwaukee P.O. Box 413 Milwaukee W153201 USA

This paper reports on modem developments related to nanotechnology of cement and concrete. Recent advances in instrumentation and design of advanced nano-composite materials is discussed. New technological directions and historical milestones in nanoengineering and nanomodification of cement-based materials are presented. It is concluded that there is a strong potential of nanotechnology to improve the performance of cement-based materials.

关键词： nanotechnology cement concrete nanoparticle nano-composite nanomodification carbon nanotubes C-S-Hgel photocatalyst

Influence of non-covalent interactions on properties of lanthanide systems with aromatic ligands

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Journal of Rare Earths 2008年第2期26卷 146-152页

作者： Lada Puntus konstantin Lyssenko Laboratory of Molecular Nanoelectronics Institute of Radioengineering & Electronics Russian Academy of Sciences 11-7 MokhovayaMoscow 125009 Russia A. N. Nesmeyanov Institute of Organoelement Compounds Russian Academy of Sciences GSP-1 28 Vavilov StreetMoscow 119991 Russia

Two series of lanthanide compounds, namely, chlorides containing different numbers of both 1,10-phenanthroline （Phen） molecules and chloride anions in the first coordination sphere, and Schiff Bases （SBs） derived from Pyridoxal （PL） and amino acids, were characterized by single crystal X-ray diffraction and luminescence techniques. The combined use of these techniques for the analysis of long-distance europium non-covalent interactions was performed for the first time. As a result, the correlation between supramolecular organization and the features of the Eum electronic transitions was found for the compounds of the first series. Strong non-covalent interactions between pyridoxal tings of SBs （the second series of compotmd） led to the formation of 1：2 species and four-dentate coordination function of these SBs in aqueous solution.

关键词： n-stacking interaction luminescence lanthanides halogenides Schiff base rare earths

Chemical Mechanisms of Prebiotic Chirality Amplification

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Research 2020年第1期2020卷 914-921页

作者： konstantin P.Bryliakov Novosibirsk State University Pirogova 1Novosibirsk 630090Russia Boreskov Institute of Catalysis Pr.Lavrentieva 5Novosibirsk 630090Russia

This review article surveys the recent experimental findings that suggest alternative chemical models of directed chirality amplification at the early,prebiotic *** is believed that the chirality amplification step followed the initial emergence of small enantiomeric imbalance and preceded(as a necessary condition)the occurrence of homochiral biopolymers,assembled from enantiomerically pure building *** work focuses on the chemical nature of possible mechanisms of primordial chirality enhancement,without going into detail of the preceding and subsequent phases of origination of biological homochirality and life on *** mechanisms are discussed through the prism of integrity of biological natural selection and chemical kinetic selection.

关键词： Chiral subsequent finding