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Evolution of ionization waves in a multi-pulsed plasma jet:the role of memory charges

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Plasma Science and Technology 2023年第3期25卷 95-103页

作者： n Yu BABAEvA G v nAIDIS v F TARASEnKO D A SOROKIn Cheng ZHAnG Tao SHAO Joint Institute for High Temperatures Russian Academy of Sciences Institute of High Current Electronics Siberian BranchRussian Academy of Sciences Institute of Electrical Engineering Chinese Academy of Sciences University of Chinese Academy of Sciences

In this paper,we discuss the properties of ionization waves(IWs)in a multi-pulsed plasma jet while using the two-dimensional computational *** IWs are generated by application of three short negative pulses with a repetition frequency 12.5 *** simulations are performed continuously during a single run while accounting for charges accumulated inside(surface charges)and outside(space charges)the *** plasma forming gas mixture(He/O2=99.8%/0.2%)is injected through the discharge tube into the surrounding humid *** show that an IW can emerge from the tube exit at a pulse rising edge(as a negative IW)and at a falling edge of the same pulse(as a positive IW).It is demonstrated that remnants of the negative and positive charges play an essential role in the discharge *** first pulse travels the shortest distance as it propagates through the initially non-ionized *** IWs developing during the second pulse essentially enlarge the plasma plume *** the same time,the IWs generated by the third pulse eventually decay due to the remnants of charges accumulated during the previous *** memory charges can lead to the IW extinction.

关键词： helium plasma jet multiple pulses positive and negative ionization waves

Model acupuncture point:Bone marrow-derived stromal stem cells are moved by a weak electromagnetic field

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World Journal of Stem Cells 2016年第10期8卷 342-354页

作者： Artem n Emelyanov Marina v Borisova vera v Kiryanova Laboratory of High Laser and Magnetic Technology North-Western State Medical University Training Laboratory of Physical Chemistry Institute of ChemistrySt. Petersburg State University Department of Physical Therapy and Rehabilitation North-Western State Medical University

AIM To show the existence of a structural formative role of magnetic fields(MFs) with respect to biological objects by using our proposed model of an *** We introduced a magnetised 10-100 μT metal rod(needle) into culture dishes with a negatively charged working surface and observed during 24 h how cells were arranged by MFs and by electrical fields(EFs) when attached. Rat and human bone marrow-derived stromal stem cells(r BMSCs and h BMSCs), human nonadherent mononuclear blood cells, nCTCs and A172 cells, and Escherichia coli(E. coli) were evaluated. The dish containing BMSCs was defined as the model of an acupoint. r BMSCs proliferative activity affected by the needle was investigated. For investigating electromagnetic field structures, we used the gas discharge visualisation(GDv) *** During 24 h of incubation in 50-mm culture dishes, BMSCs or the nonadherent cells accumulated into a central heap in each dish. BMSCs formed a torus(central ring) with an inner diameter of approximately10 mm only upon the introduction of the needle in the centre of the dish. The cells did not show these effects in 35- or 90-mm culture dishes or hydrophobic dishes or rectangular cuvettes. nCTCs and A172 cells showed unstable the effects and only up to two weeks after thawing. Moreover, we observed that the appearance of these effects depended on the season. In winter, BMSCs showed no the effects. GDv experiments revealed that the resonant annular illumination gradually formed from 10 to 18-20 s in polar solutions with and without cell suspension of BMSCs, nCTCs and E. coli when using circular 50-mm dishes, stimulation at 115 v and switching of the electrode poles at 1 kH z. All these data demonstrate the resonant nature of the central ring. Significant influence of MFs on the rB MSC proliferation rate was not *** BMSCs can be moved by MFs when in the presence of a constant EF and MF, when the cells are in the responsive functional state, and whe

关键词： Stem cell movement Magnetic targeting Acupuncture Model acupoint Frizzled-related protein Biology resonance Cytoplasm movement Glycocalyx

Results of the Main Phase of Ion Separation in the Process of Plasma-Optical Mass Separation

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Plasma Science and Technology 2015年第10期17卷 862-868页

作者： v.M.BARDAKOv S.D.IvAnOv A.v.KAZAnTSEv n.A.STROKIn Institute for Physics and Technology Irkutsk State Technical University

This paper presents separation results of a mixture of nitrogen, argon and krypton ions in the process of plasma-optical mass separation on the POMS-E-3 separator model. We determined the behavior of the separation with a change in the value of magnetic field induction in the azimuthator and in the degree of compensation of the spatial charge in ion flows. An analysis is performed for experimental data by correlation with the results of a theoretical study and numerical experiments. The objectives of future experiments are outlined.

关键词： plasma-optical mass separation plasma accelerator trajectories spatial charge

Quantum-dot microlasers based on whispering gallery mode resonators

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Light(Science & Applications) 2021年第5期10卷 785-795页

作者： A.E.Zhukov n.v.Kryzhanovskaya E.l.Moiseev M.v.Maximov Laboratory of quantum optoelectronics National Research University Higher School of EconomicsKantemirovskaya 3ASt.Petersburg 194100Russia nanophotonics laboratory Alferov UniversityKhlopina 8/3St.Petersburg 194021Russia

The subject of this paper is microlasers with the emission spectra determined by the whispering gallery *** to the total internal reflection of light on the sidewalls,a high Q-factor is achieved until the diameter is comparable to the *** light emission predominantly occurs in the plane of the structure,which facilitates the microlaser integration with other *** focus on microdisk lasers with various types of the In(Ga)As quantum dots(QDs).Deep localization of charge carriers in spatilly separated regions suppresses the lateral diffusion and makes it possible to overcome the undesirable effect of non-adiative recombination in deep ***,using conventional epitaxial structures and relatively simple post-growth processing methods,it is possible to realize small microlasers capable of operating without temperature stabilization at elevated *** low sensitivity of QDs to epitaxial and manufacturing defects allows fabricating microlasers using IIv heterostructures grown on silicon.

关键词： Quantum mode overcome

A new Method of Synthesis of Azo Schiff Base Ligands with Azo and Azomethine Donors： Synthesis of n-4-Methoxybenzylidene-2-（3-hydroxyphenylazo）-5-hydroxyaniline and Its nickel（Ⅱ） Complex

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Chinese Journal of Chemistry 2007年第6期25卷 869-871页

作者： OFORKA, n. C. MKPEnIE, v. n. Department of Pure and Industrial Chemistry University of Port Harcourt P. M. B. 5323 Port Harcourt Nigeria

A new method for the synthesis of azo Schiff an base ligand in which the azo and azomethine groups are coordination sites was developed through a Schiff base precursor. The precursor, n-4-methoxybenzylidene-3-hydroxyphenylamine （SB） derived from 3-aminophenol was regioselectively coupled with a diazonium ion para to the hydroxyl group of the amine component of the Schiff base. The para selectivity was controlled by the directing effect of the hydroxyl group. The ligand and its nickel（Ⅱ） complex were characterized by elemental analyses, IR and Uv-vis spectroscopy. The analytical and spectral data supported the mononuclear formulation of the complex with metal to ligand ratio （M ： L = 1 ： 2） and suggested a square planar geometry for the complex.

关键词： synthesis azo compound Schiff base ligand azo and azomethine donor

Melt-spun thin ribbons of shape memory TiniCu alloy for micromechanical applications

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International Journal of Smart and nano Materials 2011年第2期2卷 68-77页

作者： A.v.Shelyakov n.n.Sitnikov v.v.Koledov D.S.Kuchin A.I.Irzhak n.Yu.Tabachkova Department of Solid State Physics and nanosystems National Research Nuclear University“MEPhI”Kashirskoe shosse 31115409 MoscowRussian Federation Department of Physics of Magnetic Phenomena Kotelnikov Institute of Radio-Engineering and Electronics of Russian Academy of SciencesMohovaya st.11/7125009 MoscowRussian Federation Department of Material Science of Semiconductors and Dielectrics National University of Science and Technology“MISiS”Leninsky prospect 4119049 MoscowRussian Federation

The development of micromechanical devices(MEMS and nEMS)on the basis of nanostructured shape memory alloys is reported.A Ti_(50)ni_(25)Cu_(25)(at.%)alloy fabricated by the melt spinning technique in the form of a ribbon with a thickness around 40µm and a width about 1.5 mm was chosen as a starting *** parameters were optimized to produce the alloy in an amorphous *** thickness of the ribbon was reduced to 5–14µm by means of electrochemical polishing.A nanostructural state of the thin ribbons was obtained via the dynamic crystallization of the amorphous alloy by application of a single electric pulse with duration in the range of 300–900µs.A microtweezers prototype with a composite cantilever of 0.8µm thick and 8µm long was developed and produced on the basis of the obtained nanostructured thin ribbons by means of the focused ion beam *** deformation of the micromanipulator was achieved by heating using semiconductor laser radiation in a vacuum chamber of scanning ion-probe microscope.

关键词： melt-spun ribbon shape memory alloy composite micromanipulator microtweezers

Malpractice or masterful practice?navigating vicarious liability in healthcare

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World Journal of Clinical Cases 2025年第2期13卷 10-13页

作者： Satvik n Pai naveen Jeyaraman Madhan Jeyaraman Swaminathan Ramasubramanian Department of Orthopaedics PES University Institute of Medical Sciences and ResearchBengaluru 560100KarnatakaIndia Department of Orthopaedics ACS Medical College and HospitalDr MGR Educational and Research InstituteChennai 600077Tamil NaduIndia Department of Orthopaedics Government Medical CollegeOmandurar Government EstateChennai 600002Tamil NaduIndia

In the intricate landscape of healthcare,vicarious liability looms large,shaping the responsibilities and actions of healthcare practitioners and administrators *** by a poignant scenario of a medication error,this article navigates the complexities of vicarious liability in *** explains the legal basis and ramifications of this theory,emphasizing its importance in fostering responsibility,protecting patient welfare,and easing access to *** paper explores the practical effects of vicarious responsibility on day-to-day operations,leadership practices,and decision-making processes via the eyes of senior consultants,junior doctors,and hospital *** comprehensive insights and real-world examples,it underscores the imperative of fostering a culture of accountability,communication,and quality care to navigate the intricate web of liabilities inherent in modern healthcare.

关键词： vicarious liability Healthcare Responsibility Litigation Patient welfare

Anode Plasma Electrolytic Saturation of Titanium Alloys with nitrogen and Oxygen

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Journal of Materials Science & Technology 2016年第10期32卷 1027-1032页

作者： P.n.Belkin S.A.Kusmanov A.v.Zhirov v.S.Belkin v.I.Parfenyuk nekrasov Kostroma State University 1 May14Kostroma 156961Russia

In this work, we investigated the features of the anode plasma electrolytic saturation of titanium alloys with nitrogen and oxygen. In this case, the titanium samples may be heated to 1050 ℃ using aqueous solutions of ammonium chloride as working electrolyte. The weight of titanium samples is found to change due to their oxidation and anode dissolution. An X-ray diffractometer, a scanning electron microscope,nuclear proton backscattering and an optical microscope were used to characterize the phase and elemental composition of the modified layer. The electrolyte composition（10 wt% ammonium chloride, 5wt% ammonia） and processing mode（850 ℃, 5 min） of commercially pure titanium（CP-Ti） allowing to obtain the hardened surface layer up to 0.1 mm with microhardness of 220 Hv were proposed. Surface roughness Ra of samples after their nitriding for 5 min at 800 ℃ decreases from 1.67 to 0.082 μm. The anode plasma electrolytic nitriding could decrease friction coefficient and increase wear resistance of the CP-Ti. It is found that the anodic nitriding of low alloy titanium alloys reduces their corrosion rate in an aqueous solution of sulphuric（4.5%） and salt（0.2%） acids by 2 orders of magnitude. Results of cyclic testing show that anodic nitriding of commercial titanium leads to a decrease in corrosion rate by 8 times in solution of hydrochloric acid（6%） with addition of protein and vitamin.

关键词： Plasma electrolysis Titanium nitriding Wear Corrosion

Glass and cellulose acetate fibers-supported boehmite nanosheets for bacteria adsorption

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Progress in natural Science:Materials International 2017年第2期27卷 268-274页

作者： n.v.Svarovskaya O.v.Bakina E.A.Glazkova A.n.Fomenko M.I.Lerner Institute of Strength Physics and Materials Sciences of the Siberian Branch of the Russian Academy of Sciences national Research Tomsk Polytechnic University

In this work, in situ method of producing hybrid fibrous adsorbents in which boehmite nanosheets with high sorption properties formed on the surface of hydrophilic microfibres, such as cellulose acetate and glass fibre,was described. The boehmite nanosheets were fabricated by the reaction of composite Al n/Al nanoparticles with water at 60 °C. The synthesized samples were characterized by X-ray diffractometer, scanning, transmission electron microscopy, Fourier transform infrared spectrometer(FT-IR), zeta-potential and specific surface area analyzers. The introduction of microfibres into a diluted aqueous suspension of nanopowders causes heteroadagulation of the nanoparticles and accelerates their further transformation. This effect is most substantial with the glass microfibre, which is thought to have a higher concentration of surface groups capable of generating hydrogen bonds that act as heteroadagulation and nucleation centres. The experimental results showed that the morphology of the resultant hybrid fibrous adsorbents differed accordingly: the nanosheets were attached on-edge to the glass microfibre surface, while on the surface of the cellulose acetate microfibre,they were secured in the form of spherical "nanoflowers" of agglomerated nanosheets. The effect of the morphology of hybrid fibrous adsorbents on adsorption bacteria Escherichia coli was also investigated.

关键词： nanosheets Microfibres Hybrid materials Bacterial adsorption