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Magnetic and XPS studies of lithium lanthanide tetraphosphates LiLnP_4O_(12)(Ln=Nd,Gd,Er)

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Journal of Rare Earths 2013年第5期31卷 485-489页

作者： D.Petrov b.Angelov v.Lovchinov Department of Physical Chemistry Plovdiv University"Paisii Hilendarski" 24 Tsar Asen Str. 4000 Plovdiv Bulgaria Department of Inorganic and Physical Chemistry University of Food Technologies-Plovdiv26 Maritsa Blvd. 4002 Plovdiv Bulgaria Institute of Solid State Physics Bulgarian Academy of Sciences72Tsarigradsko Chaussee Blvd.1784 SofiaBulgaria

Magnetic susceptibilities of flux-grown single crystals of LitnP4012 （Ln=Nd, Gd, Er） were measured in the temperature range of 2-300 K. The compounds were paramagnetic, and obeyed the Curie-Weiss law in the entire temperature interval, without magnetic phase transitions, and with effective magnetic moments close to those of the corresponding free Ln3＋ ions. X-ray photoelec- tron spectroscopy was applied to determine the positions of core-level electrons relative to the Fermi level： Li is; Ln 4f, 5p, 5s, 4d, 3d; P 2s, 2p; O 1s, 2s. The binding energies in these compounds were found slightly shifted compared to the respective values of the same elements.

关键词： lithium lanthanide tetraphosphates single crystals magnetic properties XPS spectroscopy rare earths

Influence of Small-Size Contaminations on Thin Film Structural Properties

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Chinese Physics Letters 2019年第3期36卷 82-85页

作者： F.v.Grigoriev v.b.Sulimov Jinlong Zhang Xinbin Cheng Zhanshan Wang A.v.Tikhonravov Research Computing Center M.V.Lomonosov Moscow State University MOE Key Laboratory of Advanced Micro-Structured Materials Institute of Precision Optical Engineering School of Physics Science and EngineeringTongji University IFSA Collaborative Innovation Center Shanghai Jiao Tong University

An approach for studying the influence of nano-particles on the structural properties of deposited thin films is proposed. It is based on the molecular dynamic modeling of the deposition process in the presence of contaminating nano-particles. The nano-particle is assumed to be immobile and its interaction with film atoms is described by a spherically symmetric potential. The approach is applied to the investigation of properties of silicon dioxide films. visualization tools are used to investigate the porosity associated with nano-particles. The structure of the film near the nano-particle is studied using the radial distribution function. It is found that fluctuations of film density near the nano-particles are essentially different in the cases of low-energy and high-energy deposition processes.

关键词： Influence Small-Size Properties

RMCARTAM For DDoS Attack Mitigation in SDN Using Machine Learning

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Computer Systems Science & Engineering 2023年第6期45卷 3023-3036页

作者： M.Revathi v.v.Ramalingam b.Amutha Department of Computing Technologies SRM Institute of Science and TechnologyKattankulathurChennai603203Tamil NaduIndia

The impact of a Distributed Denial of Service(DDoS)attack on Soft-ware Defined Networks(SDN)is briefly *** approaches to detecting DDoS attacks exist,varying on the feature being considered and the method ***,the methods have a deficiency in the performance of detecting DDoS attacks and mitigating *** improve the performance of SDN,an efficient Real-time Multi-Constrained Adaptive Replication and Traffic Approximation Model(RMCARTAM)is sketched in this *** RMCARTAM considers different parameters or constraints in running different controllers responsible for handling incoming *** model is designed with multiple controllers to handle net-work traffic but can turn the controllers according to *** multi-con-straint adaptive replication model monitors different features of network traffic like rate of packet reception,class-based packet reception and target-specific *** to these features,the method estimates the Replication Turn-ing Weight(RTW)based on which triggering controllers are ***,the method applies Traffic Approximation(TA)in the detection of DDoS *** detection of a DDoS attack is performed by approximating the incoming traf-fic to any service and using various features like hop count,payload,service fre-quency,and malformed frequency to compute various support measures on bandwidth access,data support,frequency support,malformed support,route sup-port,and so *** all these support measures,the method computes the value of legitimate weight to conclude the behavior of any source in identifying the mal-icious *** node details are used in the mitigation of DDoS *** method stimulates the network performance by reducing the power factor by switching the controller according to different factors,which also reduces the *** the same way,the proposed model improves the accuracy of detecting DDoS attacks by estimating the features of incoming traffic in

关键词： DDoS SDN traffic approximation adaptive replication multi-controller support measures RTW

Lanthanide NIR luminescence for telecommunications, bioanalyses and solar energy conversion

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Journal of Rare Earths 2010年第6期28卷 824-842页

作者： Jean-Claude G. bünzli Svetlana v. Eliseeva cole Polytechnique Fédérale de Lausanne Institute of Chemical Sciences and Engineering WCU Professor Korea University Center for Next Generation Photovoltaic Systems Katholieke Universiteit Leuven Department of Chemistry Laboratory of Coordination Chemistry

Present-day advanced technologies heavily rely on the exciting magnetic and spectroscopic properties of lanthanide ions. In particular, their ability to generate well-characterized and intense near-infrared (NIR) luminescence is exploited in any modern fiber-optic telecommunication network. In this feature article, we first summarize the whereabouts underlying the design of highly luminescent NIR molecular edifices and materials. We then focus on describing the main trends in three applications related to this spectral range: telecommunications, biosciences, and solar energy conversion. In telecommunications, efforts concentrate presently on getting easily processable polymer-based waveguide amplifiers. Upconversion nanophosphors emitting in the visible after NIR excitation are now ubiquitous in many bioanalyses while their application to bio-imaging is still in its early stages; however, highly sensitive NIR-NIR systems start to be at hand for both in vitro and in vivo imaging, as well as dual probes combining magnetic resonance and optical imaging. Finally, both silicon-based and dye-sensitized solar cells benefit from the downconversion and upconversion capabilities of lanthanide ions to harvest Uv and NIR solar light and to boost the overall quantum efficiency of these next-generation devices.

关键词： lanthanide luminescence near-infrared luminescence telecommunications bioanalysis solar energy conversion solar cell upconversion downconversion

AN M/M/C RETRIAL QUEUEING SYSTEM WITH bERNOULLI vACATIONS

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Journal of Systems Science and Systems Engineering 2009年第2期18卷 222-242页

作者： b.Krishna KUMAR R.RUKMANI v.THANGARAJ Department of Mathematics College of EngineeringAnna UniversityChennai600 025India Department of Mathematics Pachaiyappa's CollegeChennai600030India Ramanujan Institute for Advanced Study in Mathematics University of MadrasChennai600 005India

In this paper, a steady-state Markovian multi-server retrial queueing system with bernoulli vacation scheduling service is studied. Using matrix-geometric approach, various interesting and important system performance measures are obtained. Further, the probability descriptors like ideal retrial and vain retrial are provided. Finally, extensive numerical illustrations are presented to indicate the quantifying nature of the approach to obtain solutions to this queueing system.

关键词： Retrial queue bernoulli vacation matrix-geometric methods busy period vain retrial ideal retrial

Influence of the safety factor profile on the particle and heat transport in the Globus-M spherical tokamak

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Plasma Science and Technology 2019年第11期21卷 1-6页

作者： A YU TELNOvA G S KURSKIEv E O KISELEv N N bAKHAREv v K GUSEv N A KHROMOv S YU MEDvEDEv v b MIINAEv I v MIROSHNIKOv M I PATROv Yu v PETROv N v SAKHAROv A D SLADKOMEDOvA P b SHCHEGOLEv v v SOLOKHA v A TOKAREv S YU TOLSTYAKOv E A TUKHMENEvA Ioffe Institute Saint-Petersburg 194021Russia Keldysh Institute Russian Academy of SciencesMoscow 125047Russia NRC'Kurchatov Institute’ Moscow 123098Russia

The advanced tokamak scenario is a promising operation scenario for ITER and fusion neutron *** this scenario the minimum value of the safety factor in the center of the plasma exceeds *** the compact spherical tokamak Globus-M,the formation of such conditions is possible with neutral beam injection at the current ramp-up *** to the slower diffusion of current inside the plasma,a zone is formed with reduced heat and particle transport across the magnetic field,which affects the temperature and density profiles of the *** leads to the peaked density profile formation and improvement of the energy confinement *** achieve a high fraction of the bootstrap current,it is necessary to increase the plasma *** the same time,the maximum allowable pressure is limited to the normalized beta limit.

关键词： advanced tokamak mode transport analysis internal transport barriers

Effect of bagasse ash reinforcement on the wear behaviour of Al-Cu-Mg/bagasse ash particulate composites

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Acta Metallurgica Sinica(English Letters) 2010年第2期23卷 81-89页

作者： v.S. Aigbodion S.b. Hassan G.b. Nyior T. Ause Department of Metallurgical and Materials Engineering Ahmadu Bello University

The effect of bagasse ash （bAp） particle reinforcement on the wear behavior of Al-Cu- Mg alloy has been studied. bagasse ash particles were varied from 0 wt pct-10 wt pct with interval of 2 wt pct. Unlubricated pin-on disc tests were conducted to examine the wear behaviour of the aluminium alloy/bagasse ash particulate composites. The tests were conducted at varying loads, from 5 to 20 N and sliding speeds of 1.26 m/s, 2.51 m/s, 3.77 m/s and 5.02 m/s for a constant sliding distance of 5000 m. The results showed that the wear rates of the A1-Cu-Mg/bAp composites are lower than that of the matrix alloy and further decrease with increasing bagasse ash content. Wear rate increases as the sliding speed and applied load increase. The microstructure of the worn surface revealed that a large amount of plastic deformation appeared on the surface of the unreinforced alloy. While bagasse ash reinforced Al-Cu-Mg alloy showed worn out surface that is not smooth, and grooves, scratches and parallel lines were observed. A combination of adhesion and delamination wear was in operation. These results show that improve wear properties is achievable for the aluminium alloy by the addition of bagasse ash particles as reinforcement material.

关键词： Al-Cu-Mg alloy bagasse ash Composites Load Sliding speed and Wear

A SUMMATION FORMULA FOR ESTIMATING THE SURFACE AREAS OF ELLIPSOIDS

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Journal of Computational Mathematics 2004年第3期22卷 403-406页

作者： AnilKumar v.vishnu b. KelappajiCollegeofAgriculturalEngineeringandTechnology KeralaAgriculturalUniversityTavanurKerala679573India

In this paper a summation formula for finding the surface area of general ellipsoids is derived.

关键词： Ellipsoid Oblate spheroid Prolate spheroid Summation formula

Ferrofluid nucleus phase transitions in an external uniform magnetic field

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Chinese Physics b 2015年第10期24卷 322-330页

作者： b.M.Tanygin S.I.Shulyma v.F.Kovalenko M.v.Petrychuk Faculty of Radiophysics Taras Shevchenko National University of Kyiv

The phase transition between a massive dense phase and a diluted superparamagnetic phase has been studied by means of a direct molecular dynamics simulation. The equilibrium structures of the ferrofluid aggregate nucleus are obtained for different values of a temperature and an external magnetic field magnitude. An approximate match of experiment and simulation has been shown for the ferrofluid phase diagram coordinates ＂field-temperature＂. The provided phase coexistence curve has an opposite trend comparing to some of known theoretical results. This contradiction has been discussed. For given experimental parameters, it has been concluded that the present results describe more precisely the transition from linear chains to a dense globes phase. The theoretical concepts which provide the opposite binodal curve dependency trend match other experimental conditions： a diluted ferrofluid, a high particle coating rate, a high temperature,and/or a less particles coupling constant value.

关键词： ferrofluid aggregate phase diagram molecular dynamics