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journal of Materials science & Technology 2016年第7期32卷 660-670页

作者： s.Y. Park W.j. Kim Department of Materials science and Engineering Hongik University 72-1 Sangsu-dong Mapo-gu Seoul 121-791 Republic of Korea Advanced Fusion Process R&D Group Korea Institute of Industrial Technology 994-32 Dongchun-dong Yeonsu-gu Incheon 406-130 Republic of Korea

The deformation mechanisms and processing maps of the as-cast Al-Zn-Mg-Cu （？0？5） aluminum （AI） alloy were studied and compared with those of the homogenized 7075 Al alloy in the temperature range of 573-723 K and in the strain rate range of 10 3-10 s-1 to explore a possibility for directly using the as- cast 7075 Al alloy as a billet for hot working. The as-cast and homogenized 7075 A1 alloys had similar grain sizes and showed similar high-temperature deformation behaviors. The as-cast 7075 Al alloy, however, exhibited higher power efficiencies and smaller unstable flow regions compared to the homogenized 7075 AI alloy because of the presence of secondary phases （MgZn2） segregated at the dendritic interfaces in the as-cast microstructure, which were formed during non-equilibrium solidification. These segregated phases provided nucleation sites for dynamic recovery or continuous dynamic recrystallization, and as a result a fine and more homogeneous （sub）grain structure could be obtained from the as-cast micro- structure compared to the homogenized microstructure. The current work suggested the possibility and advantage of using as-cast microstructures for hot working of aluminum alloys with high content of solutes.

关键词： Al-based alloysProcessing mapHot compressionAs-cast microstructuresegregationRecrystallization

Adaptive optics in laser processing

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Light(science & Applications) 2019年第1期8卷 140-155页

作者： Patrick s.salter Martin j.Booth Department of Engineering science University of OxfordParks RoadOxford OX13PJUK

Adaptive optics are becoming a valuable tool for laser processing,providing enhanced functionality and flexibility for a range of *** a single adaptive element,it is possible to correct for aberrations introduced when focusing inside the workpiece,tailor the focal intensity distribution for the particular fabrication task and/or provide parallelisation to reduce processing *** is particularly promising for applications using ultrafast lasers for threedimensional *** review recent developments in adaptive laser processing,including methods and applications,before discussing prospects for the future.

关键词： laser optics workpiece

Combustion synthesis of Ce^(3+), Eu^(3+) and Dy^(3+) activated NaCaPO_4 phosphors

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journal of Rare Earths 2011年第6期29卷 527-535页

作者： K N shinde s j Dhoble Animesh Kumar Department of Physics RTM Nagpur University National Environmental Engineering Research Institute

The preparation of NaCaPO4 doped with rare earth （RE） ions Ce3＋, Eu3＋ and Dy3＋ by combustion method was described. Under UV excitation （251 nm） of NaCaPO4：Ce3＋ showsd emission （367 nm） in UV range. When NaCaPO4：Dy3＋ phosphor was excited at 349 nm, the emission spectrum showed intense bands at 482 nm （blue） and 576 nm （yellow）. In Eu activated NaCaPO4 phosphor, the emission spectrum showed a dominant peak at 594 nm （orange） while others were at 614 and 621 nm （red） when excited at 393 nm. The prepared phosphor was characterized by X-ray diffraction （XRD）, scanning electron microscope （sEM） and photoluminescence （PL） measurement. Thus, the photoluminescence behavior of NaCaPO4：Ce3＋ was strongly suggested for scintillator. Likewise, Eu3＋ and Dy3＋ activated NaCaPO4 phosphors were recommended for near-UV white light-emitting diodes （LEDs）.

关键词： combustion synthesis photoluminescence phosphor scintillator solid state lighting rare earths

Effects of bottom shear stresses on the wave-induced dynamic response in a porous seabed:PORO-WssI (shear) model

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Acta Mechanica sinica 2011年第6期27卷 898-910页

作者： j.Ye D.-s.jeng Division of Civil Engineering University of Dundee Center for Marine Geotechnical Engineering State Key Laboratory of Ocean EngineeringShanghai Jiao Tong University

When ocean waves propagate over the sea floor,dynamic wave pressures and bottom shear stresses exert on the surface of *** bottom shear stresses provide a horizontal loading in the wave-seabed interaction system,while dynamic wave pressures provide a vertical loading in the ***,the bottom shear stresses have been ignored in most previous studies in the *** this study,the effects of the bottom shear stresses on the dynamic response in a seabed of finite thickness under wave loading will be examined,based on Biot＇s dynamic poro-elastic *** the model,an ＂u-p＂ approximation will be adopted instead of quasi-static model that have been used in most previous *** results indicate that the bottom shear stresses has certain influences on the wave-induced seabed dynamic ***,wave and soil characteristics have considerable influences on the relative difference of seabed response between the previous model（without shear stresses） and the present model（with shear stresses）.As shown in the parametric study,the relative differences between two models could up to 10% of p0,depending on the amplitude of bottom shear stresses.

关键词： Bottom shear stresses Wave-induced dynamicresponse Porous seabed - "u-p" approximation - Biot's the-ory

Performance of inclined pillars with a major discontinuity

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International journal of Mining science and Technology 2019年第3期29卷 437-443页

作者： K.V.jessu A.j.s.spearing Western Australia school of Mines Kalgoorlie Curtin University

Discontinuities are an inherent part of the rock mass and majorly affect the stability of the excavation skin and *** dip of the discontinuities and their properties also have a significant effect on the strength of the *** approaches are commonly used to determine the pillar strength but can overestimate the strength and don’t consider the inclination of the pillars and the strength reduction caused by *** modeling is a powerful tool and if calibrated can be used to evaluate the strength of the pillars with discontinuities having a range of *** effect of a discontinuity on inclined pillars was conducted which has been seldom considered in evaluating the pillar ***-dimensional vertical pillars were simulated,and the pillar strength was calibrated to accepted theoretical results and then the discontinuities were introduced in different pillar inclinations with distinct width to height ratios to gain an insight into the effective pillar strength *** upon the results,it was found that the discontinuities have a significant effect with the increase in the inclination of the pillars even at a higher width to height ratios.

关键词： Numerical modelling Pillar Discontinuities Inclination Width to height ratios

synthesis and photoluminescence studies of Ba(Gd,Ln)B_9O_(16):Eu^(3+)(Ln=La,Y) phosphors for n-UV LED lighting and display devices

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journal of Rare Earths 2015年第2期33卷 140-147页

作者： V.V.Rangari s.j.Dhoble Department of Physics RTM Nagpur University

BaGdB9O16：Eu^3＋ and Ba（Gd,Ln）B9O16：Eu^3＋（Ln=La, Y） phosphors were synthesized by solid state diffusion method. The X-ray diffraction, scanning electron microscopy（sEM） and photoluminescence properties were investigated. The as-synthesized BaGdB9O16：Eu^3＋ and Ba（Gd,Ln）B9O16：Eu^3＋（Ln=La, Y） phosphors showed strong red emission under ultraviolet light excitation. By partially substituting Gd^3＋ by La^3＋ and Y^3＋ ions in the host BaGdB9O16：Eu^3＋ materials, the maximum emission intensity was observed for the optimum composition of BaGd0.91La0.8B9O16Eu0.01 phosphor. The experimental results indicated that the Eu doped BaGdB9O16 and Ba（Gd,Ln）B9O16（Ln=La, Y） phosphors were promising red phosphors, which might find potential applications in near-UV excited LED lighting as well as display devices. Comparison of as-synthesized phosphors with standard phosphor used in CFL（compact fluorescent lamp） was also done. Energy transfer mechanism of Gd^3＋ to Eu^3＋ was also discussed in this paper.

关键词： phosphor solid state diffusion display devices photoluminescence rare earths

Experimental and Numerical Investigation on Impact Performance of Carbon Reinforced Aluminum Laminates

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journal of Materials science & Technology 2010年第4期26卷 327-332页

作者： s.H. song Y.s. Byun T.W. Ku W.j. song j. Kim B.s. Kang National Core Research Center Pusan National University Busan 609-735 Korea Dept. of Aerospace Engineering Pusan National University Busan 609-735 Korea Industrial Liaison Innovation Cluster Pusan National University Busan 609-735 Korea

It is known that fiber metal laminates （FML） as one of hybrid materials with thin metal sheets and fiber/epoxy layers have the characteristics of the excellent damage tolerance, fatigue and impact properties with a relatively low density. Therefore, the mechanical components using FML can contribute the enhanced safety level of the sound construction toward the whole body. In this study, the impact performance of carbon reinforced aluminum laminates （CARAL） is investigated by experiments and numerical simulations. Drop weight tests are carried out with the weight of 4.7 kg at the speed of 1 and 2 m/s, respectively. Dynamic non-linear transient analyses are also accomplished using a finite element analysis software, ABAQUs. The experiment results and numerical results are compared with impact load-time histories. Also, energy-time histories are applied to investigate the impact performance of CARAL.

关键词： Fiber metal laminates (FML) Carbon reinforced aluminum laminates (CARAL) Numerical simulation Impact performance

Health risk of whole body vibration in mining trucks during various operational conditions

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journal of Central south University 2017年第8期24卷 1808-1816页

作者： Rahimdel M.j Mirzaei M sattarvand j Hoseinie s.H Department of Mining Engineering Sahand University of TechnologyTabriz ***Iran Department of Mechanical Engineering Sahand University of TechnologyTabriz ***Iran Department of Mining Engineering Isfahan University of TechnologyIsfahan ***Iran

Mining machineries are generally exposed to intensive vibrations in harsh mining environment. If vibrations are beyond the tolerable limit, the machine and its operator health will be under the risk. In this work, the vibration of a mining truck at different operational conditions are simulated and discussed. To achieve this aim, three haul roads with low, medium and poor qualities are considered based on the IsO standard. Accordingly, the vibration of a mining truck in different speeds, payload and distribution qualities of materials in the dump body are evaluated in each haul road quality using Trucksim software. The simulation results with statistical discussions indicate that the truck speed and the materials distribution quality have significant effects on the root mean square(RMs) of vertical vibrations. However, the effect of the payload is not considerable on the RMs. Moreover, the accumulation of materials on the rear side of the truck dump body is efficient on the vibrational health risk.

关键词： mining trucks operational conditions health risk whole body vibration

structure, formation, and decay of ■NN system by Faddeev-AGs calculations

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Chinese Physics C 2019年第6期43卷 21-31页

作者： s.Marri s.Z.Kalantari j.Esmaili Department of Physics Isfahan University of TechnologyIsfahan 84156-83111Iran Department of Physics Faculty of Basic Sciences Shahrekord UniversityShahrekord115Iran

The Faddeev AGs equations for the coupled-channels ■NN-πΣN system with quantum numbers I=1/2 and s=0 are solved. Using separable potentials for the ■N-πΣ interaction, we calculate the transition probability for the(YK)I=0 + N→πΣN reaction. The possibility to observe the trace of the K-pp quasi-bound state in πΣN mass spectra was studied. Various types of chiral-based and phenomenological potentials are used to describe the ■N-πΣ interaction. Finally, we show that we can observe the signature of the K-pp quasi-bound state in the mass spectra, as well as the trace of branch points in the observables.

关键词： Faddeev method ■N interaction K^-pp system quasi-bound state

Iterative inversion of global magnetospheric information from energy neutral atom (ENA) images recorded by the TC-2/NUADU instrument

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science China(Technological sciences) 2008年第10期51卷 1731-1744页

作者： s. MCKENNA-LAWLOR s. BARABAsH j. BALAZ space Technology Ireland National University of Ireland Maynooth Co. Kildare Ireland swedish Institute of space Physics Kiruna Sweden space Technology Ireland National University of Ireland Maynooth Co. Kildare Ireland Institute of Experimental Physics Kosice Slovakia

A method is presented for retrieving the magnetospheric ion distribution from En-ergetic Neutral Atom (ENA) measurements made by the NUADU instrument on the TC-2 spacecraft. Based on the already well-established method of constrained lin-ear inversion, an iterance technique suitable for the low count ENA measurements has been developed which is tolerant of the noise background. By the iterance technique, it is possible for the first time to simultaneously retrieve the magneto-spheric ion distribution and the exospheric neutral density, and further to recover global ENA emissions in three dimensions. The technique is applied to a repre-sentative ENA image recorded in energy channel 2 (protons: 50―81 keV) of the NUADU instrument during a major geomagnetic storm and it is, thereby, shown that the retrieval method developed provides a useful tool for extracting ion distribution information from ENA data.

关键词： Energetic Neutral Atom (ENA) ring current magnetospheric ions exospheric neutral density