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Effect of Vanadium Microalloying on the HAZ Microstructure and Properties of Low Carbon Steels

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Journal of Iron and Steel Research International 2011年第S1期18卷 393-403页

作者： Milbourn D baker t N Vanitec ltd Winterton HouseHigh StreetWesterhamKentTN16 1AQUK Metallurgy and Engineering Materials Group Department of Mechanical EngineeringUniversity of StrathclydeG1 1XNUK

Four Steels,C-Mn-0.05V,C-Mn-0.11V,C-Mn-0.03Nb and C-Mn were subjected to heat treatment to simulate the microstructure of a coarse grained heat affected zone (CGHAZ) and an intercritically reheated coarse grained heat affected zone (ICCGHAZ).this involved reheating to 1350°C,rapid cooling (Δt 8/5 =24s) to room temperature and then reheating to either 750°C or 800°*** toughness of the HAZs was assessed using both Charpy and CtOD *** features were characterised by optical,scanning` and transmission electron *** examinations of the Charpy and CtOD specimens were carried out to understand the micromechanism of fracture under different microstructural and test *** CGHAZ toughness was similar for the steels except that Steel C-Mn-0.05V had a slightly lower Itt compared to the *** toughness deteriorated in the ICCGHAZ for all the steels,again Steel C-Mn-0.05V had a superior toughness compared to the other three steels in both ICCGHAZ *** the level of vanadium to 0.11% caused a decrease in ICCGHAZ *** C-Mn-Nb exhibited a greater degradation of impact toughness after the intercritical *** presence of M-A constituents was the dominant factor in determining the toughness of the *** size and area fraction of the M-A constituents were the smallest in Steel *** vanadium level to 0.11% resulted in a greater area fraction of the M-A constituents,larger average and maximum sizes of M-A particles,and significantly more fields containing the *** addition of 0.031% Nb produced the largest M-A particles and the greatest area fraction for the steels tested.

关键词： vanadium microalloyed steel coarse grained heat affected zone intercritically reheated coarse grained heat affected zone martensite-austenite constitute heat affect zone toughness

Labial tip sensilla of blissus leucopterus leucopterus （Hemiptera： blissidae）： Ultrastructure and behavior

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Insect Science 2008年第3期15卷 271-275页

作者： Gerald t. baker Xiong Chen Peter W.K. Ma Department of Entomology and Plant Pathology Box 9775 Mississippi State University Mississippi State MS 39762 USA

the cuticular sensory receptors that are found on the apex of the labium of hemipterans play an important role in their feeding behavior. In this study we describe the ultrastructure, number, and distribution of sensilla on the labium apex of the chinch bug, blissus leucopterus leucopterus. Each apical field of sensilla on the labium contains 11 uniporous peg sensilla and one sensillum chaeticum. the uniporous peg sensilla are innervated by 4-5 bipolar neurons that send dendrites in the lumen of each peg. three neurons are associated with each sensillum chaeticum, two neurons have dendrites in the lumen of the sensillum, and the third dendrite ends in a tubular body at the base of the sensillum. behavioral tests that involve chemical blockage of the sensory receptors show the importance of the labial sensilla in feeding behavior. both morphological and behavioral evidence indicate that the labial sensilla have a chemosensitive function.

关键词： behavioral tests chinch bug electron microscopy labial sensilla Nmethylmaleimide

Measuring vacuum polarization with high-power lasers

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High Power Laser Science and Engineering 2016年第1期4卷 29-40页

作者： b.King t.Heinzl Centre for Mathematical Sciences Plymouth University

When exposed to intense electromagnetic fields, the quantum vacuum is expected to exhibit properties of a polarizable medium akin to a weakly nonlinear dielectric material. Various schemes have been proposed to measure such vacuum polarization effects using a combination of high- power lasers. Motivated by several planned experiments, we provide an overview of experimental signatures that have been suggested to confirm this prediction of quantum electrodynamics of real photon–photon scattering.

关键词： Heisenberg–Euler photon–photon scattering vacuum birefringence vacuum polarization

A new adaptive bending method using closed loop feedback control

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transactions of Nonferrous Metals Society of China 2010年第11期20卷 2111-2117页

作者： t.WELO b.GRANLY Department of Engineering Design and Materials Norwegian University of Science and Technology(NTNU)

As the competition from companies in low cost countries increases,the need for more automated production which reduces labour cost while improving product quality is required.A new rotary compression bending set-up with automated closed-loop feedback control is thus being *** transferring in-process measurement data into an algorithm for predicting springback and bend angle prior to the unloading sequence,the dimensional accuracy is *** work focuses on the development of this steering *** the method used does not increase cycle time,it is attractive for high-volume industrial *** than 150 bending tests of AA6060 extrusions were conducted to determine the capability of the *** results show that by activating the automated closed-loop feedback system,the dimensional accuracy of the bent parts is more than three times better than that obtained by traditional compression *** the steering model permits the direct use of additional process data,such as instant wall thickness and cross sectional distortions,it is believed that extension of the measurement capabilities would improve the accuracy of the methodology even further.

关键词： adaptive bending closed-loop feedback dimensional accuracy springback aluminium extrusion

CompactChain:an efficient stateless chain for UtXO-model blockchain

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Frontiers of Computer Science 2024年第2期18卷 167-179页

作者： b Swaroopa REDDY t Uday Kiran REDDY Department of Electrical Engineering Indian Institute of Technology HyderabadHyderabadTelangana 502285India

In this work,we propose a stateless blockchain called CompactChain,which compacts the entire state of the UtXO(Unspent transaction Output)based blockchain systems into two RSA *** first accumulator is called transaction Output(tXO)commitment which represents the tXO *** second one is called Spent transaction Output(StXO)commitment which represents the StXO *** this work,we discuss three algorithms:(i)to update the tXO and StXO commitments by the *** miner also provides the proofs for the correctness of the updated commitments;(ii)to prove the transaction’s validity by providing a membership witness in tXO commitment and non-membership witness against StXO commitment for a coin being spent by a user;(iii)to update the witness for the coin that is not yet spent;the experimental results evaluate the performance of the CompactChain in terms of time taken by a miner to update the commitments and time taken by a validator to verify the commitments and validate the *** compare the performance of CompactChain with the existing state-of-the-art works on stateless *** shows a reduction in commitments update complexity and transaction witness size which inturn reduces the mempool size and propagation latency without compromising the system throughput(transactions per second(tPS)).

关键词： stateless blockchain RSA Accumulator StXO commitment tXO commitment UtXO Non-interactive Proof of Exponentiation(NI-PoE) transactions per second(tPS)

Oxidative stress and male reproductive health

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Asian Journal of Andrology 2014年第1期16卷 31-38页

作者： Robert J Aitken tegan b Smith Matthew S Jobling Mark A baker Geoffry N De Iuliis Priority Research Centre in Reproductive Science Discipline of Biological Sciences Faculty of Science and IT University of Newcastle Callaghan NSW 2308 Australia

One of the major causes of defective sperm function is oxidative stress, which not only disrupts the integrity of sperm DNA but also limits the fertilizing potential of these cells as a result of collateral damage to proteins and lipids in the sperm plasma membrane. the origins of such oxidative stress appear to involve the sperm mitochondria, which have a tendency to generate high leve｜s of superoxide anion as a prelude to entering the intrinsic apoptotic cascade. Unfortunately, these cells have very little capacity to respond to such an attack because they only possess the first enzyme in the base excision repair （bER） pathway, 8-oxoguanine glycosylase 1 （OGG1）. the latter successfully creates an abasic site, but the spermatozoa cannot process the oxidative lesion further because they lack the downstream proteins （APE1, XRCC1） needed to complete the repair process. It is the responsibility of the oocyte to continue the bER pathway prior to initiation of S-phase of the first mitotic division. If a mistake is made by the oocyte at this stage of development, a mutation will be created that will be represented in every cell in the body. Such mechanisms may explain the increase in childhood cancers and other diseases observed in the offspring of males who have suffered oxidative stress in their germ line as a consequence of age, environmental or lifestyle factors. the high prevalence of oxidative DNA damage in the spermatozoa of male infertility patients may have implications for the health of children conceived in vitro and serves as a driver for current research into the origins of free radical generation in the germ line.

关键词： DNA damage oxidative stress oxoguanine glycosylase 1 oocyte spermatozoa

Exact solutions to drift-flux multiphase flow models through Lie group symmetry analysis

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Applied Mathematics and Mechanics(English Edition) 2015年第8期36卷 1105-1112页

作者： b.bIRA t.R.SEKHAR Department of Mathematics National Institute of Science and Technology Department of Mathematics Indian Institute of Technology Kharagpur

In the present paper, Lie group symmetry method is used to obtain some exact solutions for a hyperbolic system of partial differential equations （PDEs）, which governs an isothermal no-slip drift-flux model for multiphase flow problem. those sym- metries are used for the governing system of equations to obtain infinitesimal transforma- tions, which consequently reduces the governing system of PDEs to a system of ODEs. Further, the solutions of the system of ODEs which in turn produces some exact solutions for the PDEs are presented. Finally, the evolutionary behavior of weak discontinuity is discussed.

关键词： multiphase flow drift-flux models Lie group analysis exact solution weakdiscontinuity

A comparative study on microstructure,nanomechanical and corrosion behaviors of AlCoCuFeNi high entropy alloys fabricated by selective laser melting and laser metal deposition

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Journal of Materials Science & technology 2022年第36期131卷 221-230页

作者： Yaojia Ren Hong Wu bin Liu Yong Liu Sheng Guo ZbJiao Ian baker State Key Laboratory of Powder Metallurgy Central South UniversityChangsha 410083China Department of Industrial and Materials Science Chalmers University of TechnologyGothenburg SE-41296Sweden Department of Mechanical Engineering The Hong Kong Polytechnic UniversityHong Kong 999077China thayer School of Engineering Dartmouth CollegeHanover NH 03755-8000United States

the present study investigated the microstructure,nanomechanics,and corrosion behavior of AlCoCuFeNi high entropy alloys fabricated by selective laser melting(SLM)and laser metal deposition(LMD).the microstructure of SLM-processed specimens was mainly composed of columnar-grained bCC matrix(^90μm in width)and Cu-rich twinned FCC *** columnar grains grew epitaxially along the building direction and exhibited a strong{001}*** comparison,a coarse columnar-grained bCC matrix(^150μm in width)with a strongertexture,rod-like b2 precipitates,and large core-shell structured FCC phases were formed in the LMD-processed specimens due to the higher heat accumulation ***,the LMD-processed specimens showed a lower hardness,wear resistance,and corrosion resistance,but higher creep resistance and reduced Young's modulus than the SLM-processed *** cracks occurred in both types of specimens,which could not be completely suppressed due to Cu segregation.

关键词： Selective laser melting Laser metal deposition High entropy alloys Nanomechanics Corrosion

A note on general solution of Stokes equations

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Acta Mechanica Sinica 2016年第6期32卷 1044-1045页

作者： b.Sri Padmavati t.Amaranath School of Mathematics & Statistics University of Hyderabad

Li et al. (2015) claim that it is sufficient to use two harmonic functions to express the general solution of Stokes equations. In this paper, we demonstrate that this is not true in a general case and that we in fact need three scalar harmonic functions to represent the general solution of Stokes equations (Venkatalaxmi et al., 2004).

关键词： Stokes equations General solution Harmonic functions