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International Journal of Minerals,Metallurgy and Materials 2019年第1期26卷 52-63页

作者： V.H.Vargas I.Mejía V.H.Baltazar-Hernández c.Maldonado Metallurgy and Materials Research Institute Universidad Michoacana de San Nicolás de Hidalgo Edificio "U" Ciudad Universitaria Materials Science and Engineering Program Autonomous University of Zacatecas

Five advanced high-strength transformation-induced plasticity(TRIP) steels with different chemical compositions were studied to correlate the retained austenite and nonmetallic inclusion content with their physical properties and the characteristics of the resistance spot welding nuggets. Electrical and thermal properties and equilibrium phases of TRIP steels were predicted using the JMatPro? software. Retained austenite and nonmetallic inclusions were quantified by X-ray diffraction and saturation magnetization techniques. The nonmetallic inclusions were characterized by scanning electron microscopy. The results show that the contents of Si, c, Al, and Mn in TRIP steels increase both the retained austenite and the nonmetallic inclusion contents. We found that nonmetallic inclusions affect the thermal and electrical properties of the TRIP steels and that the differences between these properties tend to result in different cooling rates during the welding process. The results are discussed in terms of the electrical and thermal properties determined from the chemical composition and their impact on the resistance spot welding nuggets.

关键词： transformation-induced plasticity steel retained austenite non-metallic inclusions magnetic saturation electrical properties thermal properties resistance spot welding nugget

Optimization of casting conditions for heat and abrasion resistant large grey iron castings

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china Foundry 2007年第2期4卷 124-127页

作者： S. M. Yoo Y. S. cho c. c. Lee J. H. Kim c. H. Kim J. K. choi center for e-Design Korea Institute of Industrial TechnologyYeonsugu Sondodong 7-47Incheon 406-800Korea Kwanghee casting Mfg. co. Seogu Kyungseodong 381-75Incheon 404-170Korea R&D center Doosan Engine Co. Ltd. Sinchondong 69-3 Changwon 641-370 Korea

数字模拟技术被申请为海洋的引擎在大生铁铸造物优化扔的设计和条件。由模子充满和团结序列的模拟，以前的扔的条件的问题被分析并且标记为大柱体班机部分的改进从这些结果被导出。特别寒冷的数量和位置被优化增加机械性质并且在铸造物... 详细信息

数字模拟技术被申请为海洋的引擎在大生铁铸造物优化扔的设计和条件。由模子充满和团结序列的模拟，以前的扔的条件的问题被分析并且标记为大柱体班机部分的改进从这些结果被导出。特别寒冷的数量和位置被优化增加机械性质并且在铸造物最小化收缩和 microporosity。超声的测试，穿入测试并且机械性质测试与修改的扔为部分被执行条件。它证明在铸造物的 nodefects 被发现，生产率能清楚地被增加。机械性质也满足了要求的说明。

关键词：大型铸件灰口铁铸造条件优化耐热性耐磨性

Physical properties of spray deposited cdTe thin films:PEc performance

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Journal of Semiconductors 2011年第3期32卷 10-16页

作者： V.M.Nikale S.S.Shinde c.H.Bhosale K.Y.Rajpure Electrochemical Materials Laboratory Department of PhysicsShivaji University

p-cdTe thin films were prepared by spray pyrolysis under different ambient conditions and characterized using photoelectrochemical（PEc）,X-ray diffraction（XRD）,scanning electron microscopy,energy-dispersive analysis by X-ray（EDAX）,and optical transmission *** different preparative parameters viz solution pH, solution quantity,substrate temperature and solution concentration have been optimized by the PEc technique in order to get good-quality photosensitive *** analysis shows the polycrystalline nature of the film,having cubic structure with strong（111） *** reveal that grains are uniformly distributed over the surface of the substrate indicating the well-defined growth of polycrystalline cdTe thin *** EDAX study for the sample deposited at optimized preparative parameters shows the nearly stoichiometric cd：Te *** absorption shows the presence of direct transition with band gap energy of 1.5 *** films exhibit the highest photocurrent of 2.3 mA,a photovoltage of 462 mV,a 0.48 fill factor and 3.4%efficiency for the optimized preparative parameters.

关键词： cdTe PEc temperature concentration structure morphology composition optical

Tribological and vibrational characteristics of AISI 316L tested at elevated temperature and 600 Torr vacuum

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Defence Technology（防务技术） 2019年第1期15卷 58-64页

作者： K.Arul Raj M.P.Arunkumar P.K.c.Kanigalpula M.Karthikeyan Department of Mechanical Engineering Koneru Lakshmaiah Education Foundation Department of Mechanical Engineering RajaRajeswari College of Engineering

Friction and wear studies enable the investigation of material interaction between two sliding surfaces in contact. In the present investigation, the coefficient of friction and the wear resistance of AISI 316 L parts were studied under self-mating, dry sliding conditions using a pin-on-disc type configuration. The experiments were conducted at vacuum based high temperature pin-on-disc tribometer. The 4 mm diameter pin and 180 mm diameter disc were subjected to varying sliding velocities(0.5, 0.75 and 1.5 m/s) and were operated in 200, 400, 500 and 580 ℃ temperature at 600 Torr vacuum. The variation of specific wear rates with sliding velocities and different environmental conditions was studied. The morphology of sliding/rubbed surfaces was observed using Scanning Electron Microscope. In summary, it was found that a severe to mild wear transition occurred in sliding under operating conditions. Increased wear rates have been observed for 500 and 580 ℃ with increasing sliding velocity. Adhesive wear has been found to be predominant at 500 and 580 ℃ where as de-lamination has been observed at ambient temperature,200 and 400 ℃ in vacuum. The present paper also carried out the numerical analysis of the vibration behavior of AISI 316 L under thermal environment. Results revealed that at high temperature vibrational amplitude and natural frequency is significantly reduced. This can be attributed to the reduction in stiffness of the material at elevated temperatures. This high amplitude vibration during service can lead to high wear rate.

关键词： Pin-on-disc Sliding wear Vacuum De-lamination Scanning electron microscope Vibration

composition and phase structure dependence of mechanical and magnetic properties for AlcocuFeNi_x high entropy alloys

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Journal of Materials Science & Technology 2019年第6期35卷 1175-1183页

作者： cong Liu Wenyi Peng c.S. Jiang Hongmin Guo Jun Tao Xiaohua Deng Zhaoxia chen School of Materials Science and Engineering Nanchang University Nanchang 330031 China Institute of Space Science and Technology. Nanchang University Nanchang 330031 China

In this study, the effects of composition and phase constitution on the mechanical properties and magnetic performance of AlcocuFeNix(x = 0.5, 0.8, 1.0, 1.5, 2.0, 3.0 in molar ratio) high entropy alloys(HEAs)were investigated. The results show that Ni element could lead to the evolution from face centered cubic(Fcc), body centered cubic(Bcc) and ordered Bcc coexisting phase structure to a single Fcc phase. The change of phase constitution enhances the plasticity but reduces the hardness and strength. One of the interesting points is the excellent soft magnetic properties of AlcocuFeNixHEAs. Soft magnetic performance is dependent on composition and phase transition. AlcocuFeNi1.5 alloy, achieving a better balance of mechanical and magnetic properties, could be applied as structure materials and soft magnetic materials(SMMs). High curie temperature(>900 K) and strong phase stability below 1350 K of AlcocuFeNi0.5 alloy confirm its practicability in a high-temperature environment. Atomic size difference(δ) is utilized as the critical parameter to explain the lattice strain and phase transformation induced by Ni addition.

关键词： High entropy alloy Phase transformation Mechanical property Soft magnetic performance Atomic size difference

Understanding chemical Reactivity in Extended Systems：Exploring Models of chemical Softness in carbon Nanotubes

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物理化学学报 2018年第6期34卷 631-638页

作者： cáRDENAS c.rlos MUNOZ Macarena cONTRERAS Julia AYERS Paul W. GóMEZ Tatiana FUENTEALBA Patricio Departamento de Flsica Facultad de Ciencias Universidad de Chile Casilla 653 Santiago Chile centro para el Desarrollo de la Nanociencias y Nanotecnologia CEDENNA Avenida Ecuador 3493 Santiago Chile Nucleo de Matematicas Fisica y Estad

chemical reactivity towards electron transfer is captured by the Fukui ***,this is not well defined when the system or its ions have degenerate or pseudo-degenerate ground *** such a case,the first-order chemical response is not independent of the perturbation and the correct response has to be computed using the mathematical formalism of perturbation theory for degenerate ***-degeneracy is ubiquitous in nanostructures with high symmetry and totally extended *** the size of these systems,using degenerate-state perturbation theory is impractical because it requires the calculation of many excited *** we present an alternative to compute the chemical response of extended systems using models of local softness in terms of the local density of *** local softness is approximately equal to the density of states at the Fermi ***,such approximation leaves out the contribution of inner *** order to include and weight the contribution of the states around the Fermi level,a model inspired by the long-range behavior of the local softness is *** wall capped carbon nanotubes(SWccNT) illustrate the limitation of the frontier orbital theory in extended ***,we have used a c360 SWccNT to test the proposed model and how it compares with available models based on the local density of ***,a simple Hü ckel approximation captures the main features of chemical response of these *** results suggest that density-of-states models of the softness along simple tight binding Hamiltonians could be used to explore the chemical reactivity of more complex system,such a surfaces and nanoparticles.

关键词： Local softness Fukui function Reactivity carbon nanotubes Density of states

Nanotube-Based chemical and Biomolecular Sensors

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Journal of Materials Science & Technology 2008年第4期24卷 578-588页

作者： J.Koh B.Kim S.Hong H.Lim H.c.choi Department of Physics and Astronomy Seoul National University Shillim-Dong Kwanak-Gu Seoul 151-747 Korea Department of chemistry Pohang University of Science and Technology San 31 Hyoja-Dong Nam-Gu Pohang 790-784 Korea

We present a brief review about recent results regarding carbon nanotube （cNT）-based chemical and biomolecular sensors. For the fabrication of cNT-based sensors, devices containing cNT channels between two metal electrodes are first fabricated usually via chemical vapor deposition （cVD） process or ＂surface programmed assembly＂ method. Then, the cNT surfaces are often functionalized to enhance the selectivity of the sensors. Using this process, highly-sensitive cNT-based sensors can be fabricated for the selective detection of various chemical and biological molecules such as hydrogen, ammonia, carbon monoxide, chlorine gas, DNA, glucose, alcohol, and proteins.

关键词： chemical vapour deposition carbon nanotubes Sensors Biological molecules Surface programmed assembly

Towards high-mobility In2xGa2-2xO3 nanowire field-effecttransistors

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Nano Research 2018年第11期11卷 5935-5945页

作者： Ziyao Zhou changyong Lan SenPo Yip Renjie Wei Dapan Li Lei Shu Johnny c. Ho Department of Materials Science and Engineering City University of Hong Kong Kowloon Hong Kong 999077 China School of Optoelectronic Science and Engineering University of Electronic Science and Technology of China Chengdu 610054 China Shenzhen Research Institute City University of Hang Kong Shenzhen S 18057 China State Key Laboratory of Millimeter Waves City University of Hang Kong Kowloon Hang Kong 999077 China

Recently, owing to the excellent electrical and optical properties, n-type In2O3 nanowires (NWs) have attracted tremendous attention for application in memory devices, solar cells, and ultra-violet photodetectors. However, the relatively low electron mobility of In2O3 NWs grown by chemical vapor deposition (cVD) has limited their further utilization. In this study, utilizing in-situ Ga alloying, highly crystalline, uniform, and thin In2xGa2−2xO3 NWs with diameters down to 30 nm were successfully prepared via ambient-pressure cVD. Introducing an optimal amount of Ga (10 at.%) into the In2O3 lattice was found to effectively enhance the crystal quality and reduce the number of oxygen vacancies in the NWs. A further increase in the Ga concentration adversely induced the formation of a resistive β-Ga2O3 phase, thereby deteriorating the electrical properties of the NWs. Importantly, when configured into global back-gated NW field-effect transistors, the optimized In1.8Ga0.2O3 NWs exhibit significantly enhanced electron mobility reaching up to 750 cm2·V–1·s–1 as compared with that of the pure In2O3 NW, which can be attributed to the reduction in the number of oxygen vacancies and ionized impurity scattering centers. Highly ordered NW parallel arrayed devices were also fabricated to demonstrate the versatility and potency of these NWs for next-generation, large-scale, and high-performance nanoelectronics, sensors, etc.

关键词： In 2 O 3 In 2 x Ga 2−2 x O 3 nanowire chemical vapor deposition mobility oxygen vacancy

Stable Fano-like plasmonic resonance: its impact on the reversal of far-and near-field optical binding force

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communications in Theoretical Physics 2020年第4期72卷 89-105页

作者： Hamim Mahmud Rivy M R c Mahdy Nabila Masud Ziaur Rahman Jony Saikat chandra Das Department of Electrical&computer Engineering North South UniversityBashundharaDhaka1229Bangladesh School of Electrical and Electronic Engineering Nanyang Technological University50 Nanyang Ave639798 Singapore Pi Labs Bangladesh LTD ARA Bhaban39Kazi Nazrul Islam AvenueKawran BazarDhaka 1215Bangladesh

Even for a 100 nm interparticle distance or a small change in particle shape,optical Fano-like plasmonic resonance mode usually vanishes *** would be remarkable if stable Fano-like resonance could somehow be achieved in distinctly shaped nanoparticles for more than 1μm interparticle distance,which corresponds to the far electromagnetic field *** such far-field Fano-like plasmonic resonance can be achieved,controlling the reversal of the far-field binding force can be attained,like the currently reported reversals for near-field *** this work,we have proposed an optical set-up to achieve such a robust and stable Fano-like plasmonic resonance,and comparatively studied its remarkable impact on controlling the reversal of near-and far-field optical binding *** our proposed set-up,the distinctly shaped plasmonic tetramers are half immersed(***-benzene)in an inhomogeneous dielectric interface and illuminated by?circular?polarized *** have demonstrated significant differences between near-and far-field optical binding forces along with the Lorentz force field,which partially depends on the object’s shape.A clear connection is shown between the far-field binding force and the resonant modes,along with a generic mechanism to achieve controllable Fano-like plasmonic resonance and the reversal of the optical binding force in both far-and near-field configurations.

关键词： Fano resonance optical binding force Lorentz force plasmonic tetramer

Unprecedented Smart Algorithm for Uninterrupted SDN Services During DDoS Attack

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computers, Materials & continua 2022年第1期70卷 875-894页

作者： Muhammad Reazul Haque Saw chin Tan Zulfadzli Yusoff Kashif Nisar Rizaludin Kaspin Iram Haider Sana Nisar J.P.c.Rodrigues Bhawani Shankar chowdhry Muhammad AslamUqaili Satya Prasad Majumder Danda B.Rawat Richard Etengu Rajkumar Buyya Faculty of computing&Informatics Multimedia UniversityPersiaranMultimediaCyberjaya63100SelangorMalaysia Faculty of Engineering Multimedia UniversityPersiaran MultimediaCyberjaya63100SelangorMalaysia Faculty of computing and Informatics University Malaysia SabahJalan UMSKota Kinabalu Sabah88400Malaysia Telekom Malaysia Research&Development TM Innovation Centre63000CyberjayaSelangorMalaysia Federal University of Piauí(UFPI) TeresinaPIBrazil Instituto de Telecomunica珲es 6201-001Covilh?Portugal National center of Robotics and Automation-condition Monitoring Systems Lab MUETJamshoroPakistan Department of Electrical and Electronic Engineering BUETDhaka1205Bangladesh Department of Electrical Engineering and computer Science Data Science and Cybersecurity CenterHoward UniversityWashingtonDCUSA cloud computing and Distributed Systems(cLOUDS)Laboratory School of Computing and Information SystemsThe University of MelbourneMelbourneVIC 3053Australia

In the design and planning of next-generation Internet of Things(IoT),telecommunication,and satellite communication systems,controller placement is crucial in software-defined networking(SDN).The programmability of the SDN controller is sophisticated for the centralized control system of the entire ***,it creates a significant loophole for the manifestation of a distributed denial of service(DDoS)attack ***,recently a Distributed Reflected Denial of Service(DRDoS)attack,an unusual DDoS attack,has been ***,minimal deliberation has given to this forthcoming single point of SDN infrastructure failure ***,recently the high frequencies of DDoS attacks have increased *** this paper,a smart algorithm for planning SDN smart backup controllers under DDoS attack scenarios has *** proposed smart algorithm can recommend single or multiple smart backup controllers in the event of DDoS *** obtained simulated results demonstrate that the validation of the proposed algorithm and the performance analysis achieved 99.99%accuracy in placing the smart backup controller under DDoS attacks within 0.125 to 46508.7 s in SDN.

关键词： SDN smart algorithm RTZLK-DAAScP DDoS attack DRDoS