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Localized States of an Excess Electron in an ionic Cluster

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Communications in Theoretical Physics 2013年第12期60卷 738-746页

作者： K.v.Grigorishin b.i.Lev boholyubov institute for Theoretical Physics of the National Academy of Sciences of Ukraine

A theory of an electron affinity for an ionic cluster is proposed both in a quasiclassical approach and with quantization of a polarization electric field in a nanopartiele. A critical size of the cluster regarding in formation of an electron＇s autolocalized state, dependencies of energy and radius of a polaron on a cluster＇s size are obtained by a variational method. it has been found that binding energy of the electron in the cluster depends on a eluster＇s radius but a radius of electron＇s auto-localization does not depend on the cluster＇s radius and it equals to the polaron radius in a corresponding infinity crystal. A bound state of the electron in a cluster is possible only if the duster＇s radius is more than the polaron radius.

关键词： cluster polaron autolocalization phonon comfinement

Synchronized off-harmonic probe laser with highly variable pulse duration for laser-plasma interaction experiments

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High Power Laser Science and Engineering 2024年第1期12卷 99-107页

作者： J.Hornung Y.Zobus H.Lorenté C.brabetz b.Zielbauer v.bagnoud GSi Helmholtzzentrum für Schwerionenforschung GmbH DarmstadtGermany institut d’Optique UniversitéParis-SaclayPalaiseauFrance institut für Angewandte Physik Technische Universität DarmstadtDarmstadtGermany

This paper presents the development and experimental utilization of a synchronized off-harmonic laser system designed as a probe for ultra-intense laser±plasma interaction experiments. The system exhibits a novel seed-generation design,allowing for a variable pulse duration spanning over more than three orders of magnitude, from 3.45 picoseconds to 10 nanoseconds. This makes it suitable for various plasma diagnostics and visualization techniques. in a side-view configuration, the laser was employed for interferometry and streaked shadowgraphy of a laser-induced plasma while successfully suppressing the self-emission background of the laser±plasma interaction, resulting in a signal-to-self-emission ratio of 110 for this setup. These properties enable the probe to yield valuable insights into the plasma dynamics and interactions at the PHELiX facility and to be deployed at various laser facilities due to its easy-to-implement design.

关键词： interferometry laser-plasma interaction off-harmonic probe laser streaked shadowgraphy

Audio-frequency heating of particulate magnetic systems

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China Particuology 2007年第1期5卷 84-92页

作者： b.E. Kashevsky i.v. Prokhorov S.b. Kashevsky A.v. Luikov Heat and Mass Transfer institute Belarus Academy of Sciences P. Brovka str. 15 Minsk 220072 Belarus

This paper presents theoretical and experimental studies on the magnetodynamics and energy dissipation in suspensions of small ferromagnetic particles with magnetic hysteresis and mechanical mobility in an AC magnetic field. Energy absorption by particles suspended in a solid, liquid or gas environment and subjected to high frequency magnetic fields is of great interest for cancer treatment by hyperthermia, chemical technology, biotechnology and smart materials science. Sub-micron needle-like γ-Fe2O3 particles dispersed in liquid were subjected in this study to a 430 Hz magnetic field with an intensity of up to 10^5 A/m. Dynamic magnetization loops were measured in parallel to the energy dissipated in the samples. Combined magnetomechanical dynamics of particle dispersions was simulated by using a chain-of-spheres model allowing for incoherent magnetic field reversal. in liquid dispersions, within the kilohertz frequency range, the mechanical mobility of particles does not interfere with their hysteretic magnetic reversal that makes heat release comparable to that observed with solids; for instance, in the present study using γ-Fe2O3 particles in liquid subjected to 10^4 Hz field exhibited heat release rates from 250 up to 600W oer 1 cm^3 of the dry oarticle content.

关键词： AC magnetic field Particulate materials Audio-frequency heating

A novel diurnal and seasonal variation analysis of bTEX in bengaluru urban area

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Research in Cold and Arid Regions 2024年第1期16卷 14-19页

作者： H.N.Sowmya M.Dinamani G.P.Shivashankara H.K.Ramaraju b.S.Surendra vijaya v.Shanbhag R.Prajwal Department of Civil Engineering Dayananda Sagar College of EngineeringBangalore 560078India Department of Chemistry Dayananda Sagar College of EngineeringBangalore 560078India Department of Physics GFGCVijayanagarBengaluru 560040India

in the urban atmosphere of bengaluru, various volatile organic compounds(vOCs), particularly benzene,Toluene, Ethylbenzene, and Xylene(bTEX), have shown an increasing trend in concentration. The present research was conducted during summer and monsoon seasons, focusing on Kadubeesanahalli, a high-traffic area within the bengaluru Metropolitan City. Hourly sample data was collected using a bTEX analyzer(Model GC955-600) and subsequently transformed into daily, monthly, and seasonal values. The study revealed distinct patterns in benzene concentrations. benzene levels were lowest during the early morning hours, specifically from 1:00 *** 7:00 a.m.. Concentrations then increased from 7:00 a.m. to 9:00 a.m. and again from 4:00 p.m. to 11:00 p.m.,corresponding to the morning and evening peak traffic hours. However, between 10:00 a.m. and 4:00 p.m., the concentration decreased due to reduced traffic levels. These diurnal variations in benzene concentration are influenced by meteorological parameters. Comparing the two seasons, higher concentrations of benzene, Ethylbenzene, and MP-xylene were observed during the summer season. This increase is attributed to the elevated temperatures during summer, which promote the vaporization of bTEX compounds. Conversely, lower bTEX concentrations were recorded during the monsoon season due to the wet deposition process. The observed positive correlation(r > 0.5) among bTEX parameters strongly suggests a common source, most likely originating from vehicular emissions.

关键词： bTEX Summer variation Meteorological parameters Correlation

Circulating microRNA expression and nonalcoholic fatty liver disease in adolescents with severe obesity

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World Journal of Gastroenterology 2024年第4期30卷 332-345页

作者： Yi-Jie Li brittney O baumert Nikos Stratakis Jesse A Goodrich Hao-Tian Wu Jing-Xuan He Yin-Qi Zhao Max T Aung Hong-Xu Wang Sandrah P Eckel Douglas i Walker Damaskini valvi Michele A La Merrill Justin R Ryder Thomas H inge Todd Jenkins Stephanie Sisley Rohit Kohli Stavra A Xanthakos Andrea A baccarelli Rob McConnell David v Conti Lida Chatzi Department of Population and Public Health Sciences Keck School of MedicineUniversity of Southern CaliforniaLos AngelesCA 90032United States barcelona institute of Global Health Barcelona Institute of Global HealthBarcelona 08036Spain Department of Environmental Health Sciences Mailman School of Public HealthColumbia UniversityNew YorkNY 10032United States Gangarosa Department of Environmental Health Rollins School of Public HealthEmory UniversityAtlantaGA 30329United States Department of Environmental Medicine and Public Health Icahn School of Medicine at Mount SinaiNew YorkNY 10029United States Department of Environmental Toxicology University of CaliforniaDavisCA 95616United States Department of Surgery Lurie Children’s Hospital of ChicagoChicagoIL 60611United States Northwestern University Feinberg School of Medicine Northwestern UniversityChicagoIL 60611United States Division of biostatistics and Epidemiology Cincinnati Children's Hospital Medical CenterCincinnatiOH 45229United States Department of Pediatrics University of Cincinnati College of MedicineCincinnatiOH 45229United States Department of Pediatrics Children’s Nutrition Research Center USDA/ARSBaylor College of MedicineHoustonTX 77030United States Department of Gastroenterology Children’s Hospital Los AngelesLos AngelesCA 90027United States Division of Gastroenterology Hepatology and NutritionCincinnati Children's Hospital Medical CenterCincinnatiOH 45229United States

bACKGROUND Nonalcoholic fatty liver disease(NAFLD)is one of the most common chronic liver diseases in children and *** ranges in severity from isolated hepatic steatosis to nonalcoholic steatohepatitis(NASH),wherein hepatocellular inflammation and/or fibrosis coexist with *** microRNA(miRNA)levels have been suggested to be altered in NAFLD,but the extent to which miRNA are related to NAFLD features remains *** analysis tested the hypothesis that plasma miRNAs are significantly associated with histological features of NAFLD in *** To investigate the relationship between plasma miRNA expression and NAFLD features among adolescents with *** This study included 81 adolescents diagnosed with NAFLD and 54 adolescents without NAFLD from the Teen-Longitudinal Assessment of bariatric Surgery ***-operative core liver biopsies were collected from participants and used to characterize histological features of *** samples were collected during surgery for miRNA profiling.A total of 843 plasma miRNAs were profiled using the HTG EdgeSeq *** examined associations of plasma miRNAs and NAFLD features using logistic regression after adjusting for age,sex,race,and other key *** Pathways Analysis was used to identify biological functions of miRNAs that were associated with multiple histological features of *** We identified 16 upregulated plasma miRNAs,including miR-193a-5p and miR-193b-5p,and 22 downregulated plasma miRNAs,including miR-1282 and miR-6734-5p,in adolescents with ***,52,16,15,and 9 plasma miRNAs were associated with NASH,fibrosis,ballooning degeneration,and lobular inflammation,***,16 miRNAs were associated with two or more histological features of *** those miRNAs,miR-411-5p was downregulated in NASH,ballooning,and fibrosis,while miR-122-5p,miR-1343-5p,miR-193a-5p,miR-193b-5p,and miR-7845-5p were consistently and posi

关键词： MicroRNA Nonalcoholic fatty liver disease Non-alcoholic steatohepatitis Liver fibrosis Lobular inflammation ballooning degeneration

Conditions for formation and trapping of the two-ion Coulomb cluster in the dissipative optical superlattice

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Chinese Physics b 2015年第6期24卷 305-313页

作者： i.v.Krasnov institute of Computational Modeling Siberian DivisionRussian Academy of Sciences

Conditions have been studied under which a polychromatic optical superlattice can form and trap the Coulomb cluster of two strongly interacting ions. in our previous work （Krasnov i v and Kamenshchikov L P 2014 Opt. Comm. 312 192） this new all-optical method of obtaining and confining the Coulomb clusters was demonstrated by numerical simulations for special values of the optical superlattice parameters and in the case of Yb ions. in the present paper the conditions are explicitly formulated, under which the long-lived two-ion cluster in the superlattice cell is formed. The peculiarity of these conditions is the renormalization of the ion-ion Coulomb interaction. Notably, the renormalized Coulomb force is determined by the effective charge which depends on the light field parameters and can strongly differ from the ＂bare＂ ion charge. This result can be accounted for by the combined manifestation of the quantum fluctuations of optical forces, nonlinear dependence of these forces on the velocity, and non-Maxwellian （Tsallis type） velocity distribution of the ions in the optical superlattice. Explicit analytical formulas are also obtained for the parameters of the optical two-ion cluster.

关键词： optical trap ion trap rectified gradient force Coulomb clusters

Lower limb suspension induces threshold-specific alterations of motor units properties that are reversed by active recovery

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Journal of Sport and Health Science 2024年第2期13卷 264-276页

作者： Giacomo valli Fabio Sarto Andrea Casolo Alessandro Del vecchio Martino v.Franchi Marco v.Narici Giuseppe De vito Department of biomedical Sciences University of PadovaPadova 35131Italy Department Artificial intelligence in biomedical Engineering Friedrich-Alexander UniversityErlangen-Nurnberg 91052Germany

Purpose:This study aimed to non-invasively test the hypothesis that(a) short-term lower limb unloading would induce changes in the neural control of force production(based on motor units(MUs) properties) in the vastus lateralis muscle and(b) possible changes are reversed by active recovery(AR).Methods:Ten young males underwent 10 days of unilateral lower limb suspension(ULLS) followed by 21 days of *** ULLS,participants walked exclusively on crutches with the dominant leg suspended in a slightly flexed position(15°-20°) and with the contralateral foot raised by an elevated *** AR was based on resistance exercise(leg press and leg extension) and executed at 70% of each participant’s 1repetition maximum,3 times/*** voluntary isometric contraction(MvC) of knee extensors and MUs properties of the vastus lateralis muscle were measured at baseline,after ULLS,and after *** were identified using high-density electromyography during trapezoidal isometric contractions at 10%,25%,and 50% of the current MvC,and individual MUs were tracked across the 3 data collection ***:We identified 1428 unique MUs,and 270 of them(18.9%) were accurately *** ULLS,MvC decreased by 29.77%,MUs absolute recruitment/derecruitment thresholds were reduced at all contraction intensities(with changes between the 2 variables strongly correlated),while discharge rate was reduced at 10% and 25% but not at 50% *** MvC and MUs properties fully recovered to baseline levels after *** changes were observed in the pool of total as well as tracked ***:Our novel results demonstrate,non-invasively,that 10 days of ULLS affected neural control predominantly by altering the discharge rate of lower-threshold but not of higher-threshold MUs,suggesting a preferential impact of disuse on motoneurons with a lower depolarization ***,after 21 days of AR,the impaired MUs properties were fully restored to baseline levels,highlighting the plas

关键词： Disuse High-density EMG Muscle disuse Neural impairment Neuromuscular degeneration

Formation of Nanoscale intermetallic Phases in Ni Surface Layer at High intensity implantation of Al ions

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Journal of Materials Science & Technology 2004年第5期20卷 583-586页

作者： i.A.bozhko S.v.Fortuna i.A.Kurzina i.b.Stepanov E.v.Kozlov Yu.P.Sharkeev Tomsk State University of Architecture & building 2 Solyanaya pl.Tomsk 634003RussiaTomsk State University of Architecture & Building2 Solyanaya pl.Tomsk 634003RussiaTomsk State University of Architecture & Building2 Solyanaya pl.Tomsk 634003RussiaNuclear Physics InstituteTomsk Polytechnic University2a Lenin Str.Tomsk 634050RussiaTomsk State University of Architecture & Building2 Solyanaya pl.Tomsk 634003.RussiaInstitute of Strength Physics and Materials ScienceRussian Academy of Sciences2/1 Pr.AkademicheskiiTomsk 634021Russia

The results of experimental study of nanoscale intermetallic formation in surface layer of a metal target at ion implantation are presented. To increase the thickness of the ion implanted surface layer the high intensive ion implantation is used. Compared with the ordinary ion implantation, the high intensive ion implantation allows a much thicker modified surface layer. Pure polycrystalline nickel was chosen as a target. Nickel samples were irradiated with Al ions on the vacuum-arc ion beam and plasma flow source 'Raduga-5'. it was shown that at the high intensity ion implantation the fine dispersed particles of Ni3Ai, NiAl intermetallic compounds and solid solution Al in Ni are formed in the nickel surface layer of 200 nm and thicker. The formation of phases takes place in complete correspondence with the Ni-Ai phase diagram.

关键词： High intensive ion implantation ion-plasma source intermetallic nanophases

Exploring the electromagnetic shielding behavior of lanthanum doped calcium nanoferrites

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Journal of Rare Earths 2024年第11期42卷 2128-2136页

作者： E.Ahilandeswari K.Sakthipandi R.Rajesh Kanna G.Rajkumar b.Ganesh babu S.Arunmetha Aslam Hossain P.Sakthivel v.Rajendran M.Srinidhi Raghavan Department of Physics SRM TRP Engineering College Department of Electronics and Communication Engineering M. Kumarasamy College of Engineering Department of Physics Easwari Engineering College Department of Mechanical Engineering SRM TRP Engineering College Centre for Advanced Energy Studies Department of Electronics and Communication EngineeringKoneru Lakshmaiah Education Foundation Smart Materials Research institute Southern Federal University Centre for Materials Science Department of PhysicsScience and HumanitiesFaculty of EngineeringKarpagam Academy of Higher Education Centre for Nanotechnology Academy of Maritime Education and Training (Deemed to be University) Department of Chemistry and Centre for Nano-Materials and Displays B.M.S. College of Engineering

The present study focuses on the synthesis and characterization of lanthanum(La3+)-doped calcium nanoferrites(CaLaxFe2-xO4:x=0.025,0.050,0.075 and 0.100) using the sonochemical *** techniques were employed to analyze the effect of La3+infusion,Raman spectroscopy confirms the presence of active A1g,T2gand Egmodes in the CaLaxFe2-xO4nanoferrite,indicating the formation of an active ferrite *** introduction of La3+doping results in a significant increase in the band gap energy,rendering the nanoferrites insulating（3.23-3,57 ev）.At higher frequencies,the impedance studies reveal minimal losses and better AC conductivity,pointing to improved dielectric *** higher frequencies,the Q-factor of La-doped calcium nanoferrites shows lower electromagnetic *** M-H curve exhibits ferromagnetic behavior,with La3+-doped calcium nano ferrites displaying a saturation magnetization ranging from 12.72 to 18.10 emu/*** incorporation of La3+also induces enhanced electrical polarization,leading to notable dielectric loss and increased absorption of electromagnetic ***,these CaLaxFe2-xO4nanoferrites demonstrate potential as effective microwave absorbers across a wide frequency range,with significant shielding absorption observed at 8.8-9.1 GHz.

关键词： Dielectric Magnetism Microwave absorption Nanoferrites Rare earths Structural properties