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Defence Technology（防务技术） 2018年第1期14卷 77-82页

作者： B.Q.Ochieze C.C.Nwobi-Okoye p.N.Atamuo Lafarge Africa plc Mfamosing Plant Department of Mechanical Engineering Chukwuemeka Odumegwu Ojukwu University

Experimental study of the effect of wear parameters on the wear behaviour of A356 alloy reinforced with cow horn particles(CHp) produced by spark plasma sintering was investigated. Experiments were conducted based on the plan of experiments generated through Taguchi's(L9) technique. Tribometer was used for the wear test and Scanning electron microscope was used to analyse the worn scar of the samples. The results shows that, A356 alloy reinforced with CHp exhibited better dry sliding wear resistance than the unreinforced alloy. Wear rate decreased as the amount of CHp reinforcement increased in the matrix. It was found that, the optimum level of the factors with minimized the wear loss were obtained at: wt%CHp(20%), applied load(10 N), sliding velocity(3 m/s) and sliding distance(2000 m). It can be seen that the wear track of the sample are(D ? 0.81 and L = 42.85 mm) and(D ? 0.54 and L= 27.03 mm) for A356 alloy and composites at optimum condition respectively. The results showed that the addition of cow horn particles as reinforcing materials in A356 alloy composites increased the wear resistance of the composites greatly.

关键词： A356alloy Cow horn particles Microstructure Analysis of variance and wear behaviour

Toward a new era of hepatitis B virus therapeutics:The pursuit of a functional cure

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World Journal of Gastroenterology 2021年第21期27卷 2727-2757页

作者： Efthymios p Tsounis Evanthia Tourkochristou Athanasia Mouzaki Christos Triantos Division of Gastroenterology Department of Internal MedicineMedical SchoolUniversity of PatrasPatras 26504Greece Division of Hematology Department of Internal MedicineMedical SchoolUniversity of PatrasPatras 26504Greece

Hepatitis B virus(HBV)infection,although preventable by vaccination,remains a global health problem and a major cause of chronic liver *** current treatment strategies suppress viral replication very efficiently,the optimal endpoint of hepatitis B surface antigen(HBsAg)clearance is rarely ***,the thorny problems of persistent chromatin-like covalently closed circular DNA and the presence of integrated HBV DNA in the host genome are ***,the scientific community has focused on developing innovative therapeutic approaches to achieve a functional cure of HBV,defined as undetectable HBV DNA and HBsAg loss over a limited treatment period.A deeper understanding of the HBV life cycle has led to the introduction of novel direct-acting antivirals that exert their function through multiple mechanisms,including inhibition of viral entry,transcriptional silencing,epigenetic manipulation,interference with capsid assembly,and disruption of HBsAg *** parallel,another category of new drugs aims to restore dysregulated immune function in chronic hepatitis B accompanied by lethargic cellular and humoral *** of innate immunity by pattern-recognition receptor agonists leads to upregulation of antiviral cytokine expression and appears to contribute to HBV *** checkpoint inhibitors and adoptive transfer of genetically engineered T cells are breakthrough technologies currently being explored that may elicit potent HBV-specific T-cell *** addition,several clinical trials are attempting to clarify the role of therapeutic vaccination in this ***,it is increasingly recognized that elimination of HBV requires a treatment regimen based on a combination of multiple *** review describes the rationale for progressive therapeutic interventions and discusses the latest findings in the field of HBV therapeutics.

关键词： Chronic hepatitis B Functional cure Direct-acting antivirals Gene silencing Immunotherapy Therapeutic vaccination

A precise solution for prediction of fiber-reinforced concrete behavior under flexure

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Journal of Zhejiang University-Science A(Applied physics & Engineering) 2011年第7期12卷 495-502页

作者： R.AHMADI p.GHODDOUSI M.SHARIFI V.Mojarrad BAHREH Building and House Research Center Tehran 13145-1996Iran Department of Civil Engineering Iran University of Science and TechnologyTehran 16846-13114Iran Department of Civil Engineering Sharif University of TechnologyTehran 11365-11155Iran

This paper presents a precise solution to predict the behavior of steel fiber reinforced concrete(SFRC) under the four point bending test(FpBT).All the force components at the beam section(before and after cracking) are formulated by applying these assumptions:a realistic stress-strain model is used for concrete behavior in compression,a linear response is considered for the uncracked tension region in a concrete constitutive model,and an exponential relationship is proposed as a stress-crack opening in the crack region which requires two *** the moment capacity of the critical cracked section is calculated by using these forces and satisfying equilibrium law at the *** studies are done on the behavior of SFRC to assess the sensitivity of the ***,this solution is validated with some existing experimental *** result shows the proposed solution is able to estimate the behavior of SFRC under FpBT.

关键词： Steel fiber reinforced concrete(SFRC) Flexure Stress-crack opening Four point bending test(FpBT)

Cohomogeneity One de Sitter Space S1 n

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Acta Mathematica Sinica,English Series 2010年第10期26卷 1915-1926页

作者： p.AHMADI S.M.B.KASHANI H.ABEDI Department of pure Mathematics Faculty of Mathematical SciencesTarbiat Modares University Group of Mathematics School of Sciences Bu-Ali Sina University

In this paper we study the cohomogeneity one de Sitter space S1 n. We consider the actions in both proper and non-proper cases. In the first case we characterize the acting groups and orbits and we prove that the orbit space is homeomorphic to R. In the latter case we determine the groups and consequently the orbits in some different cases and prove that the orbit space is not Hausdorff.

关键词： Cohomogeneity one Lorentzian space de Sitter space

Optimal dynamic emergency reserve activation using spinning, hydro and demand-side reserves

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Frontiers in Energy 2016年第4期10卷 409-423页

作者： S. Surender REDDY p. R. BIJWE A. R. ABHYANKAR Department of Railroad and Electrical Engineering Woosong University Republic of Korea Department of Electrical Engineering Indian Institute of TechnologyDelhi India

This paper proposes an optimal dynamic reserve activation plan after the occurrence of an emergency situation （generator/transmission line outage, load increase or both）. An optimal plan is developed to handle the emergency, using the coordinated action of fast and slow reserves, for secure operation with minimum overall cost. It considers the reserves supplied by the conventional thermal generators （spinning reserves）, hydro power units and load demands （demand-side reserves）. The optimal backing down of costly/fast reserves and bringing up of slow reserves in each sub-interval in an integrated manner is proposed. The proposed reserve activation approaches are solved using the genetic algorithm, and some of the simulation results are also compared using the Matlab optimization toolbox and the general algebraic modeling system （GAMS） software. The simulation studies are performed on the IEEE 30, 57 and 300 bus test systems. These results demonstrate the advantage of the proposed integrated/dynamic reserve activation plan over the conventional/sequential approach.

关键词： demand-side reserves dynamic reserve acti-vation approach hydro power units post contingency,sequential reserve activation approach spinning reserves

Inverse design of two-dimensional materials with invertible neural networks

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npj Computational Materials 2021年第1期7卷 1822-1830页

作者： Victor Fung Jiaxin Zhang Guoxiang Hu p.Ganesh Bobby G.Sumpter Center for Nanophase Materials Sciences Oak Ridge National LaboratoryOak RidgeTN 37831USA Computer Science and Mathematics Division Oak Ridge National LaboratoryOak RidgeTN 37831USA Department of Chemistry and Biochemistry Queens College of the City University of New YorkQueensNY 11367USA

The ability to readily design novel materials with chosen functional properties on-demand represents a next frontier in materials ***,thoroughly and efficiently sampling the entire design space in a computationally tractable manner remains a highly challenging *** tackle this problem,we propose an inverse design framework(MatDesINNe)utilizing invertible neural networks which can map both forward and reverse processes between the design space and target *** approach can be used to generate materials candidates for a designated property,thereby satisfying the highly sought-after goal of inverse *** then apply this framework to the task of band gap engineering in two-dimensional materials,starting with MoS_(2).Within the design space encompassing six degrees of freedom in applied tensile,compressive and shear strain plus an external electric field,we show the framework can generate novel,high fidelity,and diverse candidates with near-chemical *** extend this generative capability further to provide insights regarding metal-insulator transition in MoS_(2)which are important for memristive neuromorphic applications,among *** approach is general and can be directly extended to other materials and their corresponding design spaces and target properties.

关键词： properties inverse satisfying

Machining of circular micro holes by electrochemical micro-machining process

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Advances in Manufacturing 2013年第4期1卷 314-319页

作者： Alok Kumar Das p. Saha AlokKumarDas·parthaSaha Indian School of Mines Dhanbad Jharkhand India Indian Institute of Technology Kharagpur KharagpurWest Bengal India

Machining of micro holes with micro electro- chemical machining （micro ECM） process has been carried out with an indigenously developed set up. This paper describes relevant problems and solutions for the circular micro holes machining process on 304 stainless steel sheets with 60 μm thickness using high speed steel cylindrical tool of diameter 500 ~tm and using dilute I-I2SO4 as elec- trolyte. The taper angle variation of the machined hole is analyzed and reported for different experimental setting parameters. The minimum value of the taper angle of machined holes is achieved at the parameter setting of 0.4 mol/L H2504, 700 kHz, 600 ns and 21 V, for stainless steel sheets and HSS tool.

关键词： Micro machining - Micro ECMMicro-hole ~ Electrochemical dissolution ~Short pulse voltage ~ pulse power supply

Exploring the configuration space of elemental carbon with empirical and machine learned interatomic potentials

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npj Computational Materials 2023年第1期9卷 987-998页

作者： George A.Marchant Miguel A.Caro Bora Karasulu Livia B.pártay Department of Chemistry University of WarwickCoventry CV47ALUK Department of Chemistry and Materials Science Aalto University02150 EspooFinland

We demonstrate how the many-body potential energy landscape of carbon can be explored with the nested sampling algorithm,allowing for the calculation of its pressure-temperature phase *** compare four interatomic potential models:Tersoff,EDIp,GAp-20 and its recently updated version,*** evaluation is focused on their macroscopic properties,melting transitions,and identifying thermodynamically stable solid structures up to at least 100 *** phase diagrams of the GAp models show good agreement with experimental ***,we find that the models’description of graphite includes thermodynamically stable phases with incorrect layer *** adding a suitable selection of structures to the database and re-training the potential,we have derived an improved model—GAp-20U+gr—that suppresses erroneous local minima in the graphitic energy *** extreme high pressure nested sampling identifies two novel stable structures in the GAp-20 model,however,the stability of these is not confirmed by electronic structure calculations,highlighting routes to further extend the applicability of the GAp models.

关键词： carbon potential configuration

pr(Ⅲ) and Nd(Ⅲ) Absorption Spectroscopic probe to Investigate Interaction with Lysozyme (HEW)

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Journal of Rare Earths 2006年第6期24卷 648-652页

作者： Jignasu p.Mehta prashant N.Bhatt Sudhindra N. Misra Department of Chemistry Bhavnagar UniversityBhavnagar-364002India

pr（ Ⅲ ） and Nd（ Ⅲ ） can be utilized as absorption spectroscopic probes to investigate the interaction of biomolecules like Lysozyme （HEW） with Ca（ Ⅱ ） in-vitro ; the most abundant metal ion in the human body system. The spectroscopic techniques involving comparative absorption, absorption difference, and quantitative intensity analysis using 4f-4f transitions are utilized for changes in the inner sphere coordination pattern of pr（ Ⅲ ） and Nd（Ⅲ ） in solution as well as in solid state. The present study deals with an important biomolecule in human metabolism, that is, Lysozyme （HEW）. The absorption er-Condon the probab spectral parameters such as the oscillator strength （p）, the Judd-Ofelt （Tλ） intensity parameters, and the Slatinter electronic parameters are calculated using chi square methods. The obtained results are used to determine le geometry of the complex in the solution, the nature of the bond between pr（Ⅲ）/Nd（Ⅲ） with lysozyme, and the inner sphere coordination environment of f-f transitions. The results obtained from various experimental conditions are utilized to investigate the coordination changes in the pr（Ⅲ）/Nd（Ⅲ） complexes caused by different coordinating sites of lysozyme, normalized bite, denticity, the solvent nature, the coordination number, the nature of bond and other parameters to mimic the interaction of the Ca（ Ⅱ ） ion with such biomolecule.

关键词： absorption spectra pr(Ⅲ), Nd(Ⅲ) Lysozyme (HEW) spectral parameters rare earths

Dynamics in large generators due to oval rotor and triangular stator shape

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Acta Mechanica Sinica 2011年第1期27卷 18-27页

作者： Niklas L.p.Lundstrm Jan-Olov Aidanp Division of Solid Mechanics Department of Applied Physics and Mechanical EngineeringLuleUniversity of Technology

Earlier measurements in large synchronous generators indicate the existence of complex whirling motion, and also deviations of shape in both the rotor and the stator. These non-symmetric geometries produce an attraction force between the rotor and the stator,called unbalanced magnetic pull（UMp）.The target of this paper is to analyse responses due to certain deviations of shape in the rotor and the *** particular,the perturbation on the rotor is considered to be of oval character,and the perturbations of the stator are considered *** numerical and analytical methods it is concluded for which generator parameters harmful conditions,such as complicated whirling motion and high amplitudes,will *** maintenance of hydro power generators the shapes of the rotor and stator are frequently *** results from this paper can be used to evaluate such measurements and to explain the existence of complex whirling motion.

关键词： Generator · Rotor · Dynamics · Asymmetric · Hydropower