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Measuring gravitational effect of superintense laser by spin-squeezed Bose-Einstein condensates interferometer

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Chinese physics B 2022年第5期31卷 265-273页

作者： Eng Boon ng C.h.Raymond Ooi Department of physics University of MalayaKuala Lumpur 50603Malaysia

We consider an extremely intense laser,enclosed by an atom *** gravitational potential generated from the high-intensity laser is solved from the Einstein field equation under the Newtonian *** compute the strength of the gravitational force and study the feasibility of measuring the force by the atom *** intense laser field from the laser pulse can induce a phase change in the interferometer with Bose-Einstein *** push up the sensitivity limit of the interferometer with Bose-Einstein condensates by spin-squeezing effect and determine the sensitivity gap for measuring the gravitational effect from intense laser by atom interferometer.

关键词： intense laser field atom interferometer Bose-Einstein condensates spin-squeezing

Multi-material additive manufacturing-functionally graded materials by means of laser remelting during laser powder bed fusion

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Frontiers of Mechanical Engineering 2023年第4期18卷 183-193页

作者： Alexander SChMIDT Felix JENSCh sebastian hÄRTEL Chair of hybrid Manufacturing Brandenburg University of TechnologyCottbus 03046Germany

Many processes may be used for manufacturing functionally graded *** them,additive manufacturing seems to be predestined due to near-net shape manufacturing of complex geometries combined with the possibility of applying different materials in one *** adjusting the powder composition of the starting material layer by layer,a macroscopic and step-like gradient can be *** further improve the step-like gradient,an enhancement of the in-situ mixing degree,which is limited according to the state of the art,is *** this paper,a novel technique for an enhancement of the in-situ material mixing degree in the melt pool by applying laser remelting(LR)is *** effect of layer-wise LR on the formation of the interface was investigated using pure copper and low-alloy steel in a laser powder bed fusion *** cross-sectional selective electron microscopic analyses were carried *** applying LR,the mixing degree was enhanced,and the reaction zone thickness between the materials was ***,an additional copper and iron-based phase was formed in the interface,resulting in a smoother gradient of the chemical composition than the case without *** Marangoni convection flow and thermal diffusion are the driving forces for the observed effect.

关键词： multi-material additive manufacturing(MMAM) functionally graded materials(FGMs) laser powder bed fusion(L-pBF) laser remelting(LR) pure copper

Formation of TiN Grid on NiTi by Laser Gas Nitriding for Improving Wear Resistance in hanks' Solution

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Journal of Materials Science & Technology 2016年第5期32卷 459-464页

作者： C.h.ng O.K.Chan h.C.Man Department of Industrial and Systems Engineering The Hong Kong Polytechnic University

Laser gas nitriding （LGN） is a common surface modification method to enhance the wear resistance of titanium （Ti） alloys, which are known to have poor tribological properties. In the present study, a titanium nitride （TIN） grid network was fabricated on the surface of nickel titanium （NiTi） by LGN. The laser processing parameters were selected to achieve nitriding without surface melting and hence to＇maintain a smooth surface finish. The characteristics of the grid-nitrided samples were investigated by scanningelectron microscopy, X-ray diffractometry, optical microscopy, 2-D profilometry, contact angle measurements and nanoindentation. The wear resistance of the nitrided samples was evaluated using reciprocating wear test against ultra-high-molecular-weight polyethylene （UhMWpE） in hanks＇ solution. The results indicate that the wear rates of the grid-nitrided samples and the UhMWpE counter-body in the wear pair are both significantly reduced. The decrease in wear rates can be attributed to the combination of a hard TiN grid and a soft NiTi substrate. In hanks＇ solution, the higher hydrophilicity of the nitrided samples also contributes to the better performance in wear test against hydrophobic UhMWpE.

关键词： Laser Nitriding Surface patterning Titanium alloys Wear

Are the well-fed less thirsty?Effects of drought and salinity on New Zealand mangroves

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Journal of plant Ecology 2022年第1期15卷 85-99页

作者： Sridevi Ravi Martin K-FBader Tim Young Mark Duxbury Michael Clearwater Cate Macinnis-ng sebastian Leuzinger School of Science Auckland University of TechnologyAucklandNew Zealand Department of Forestry and Wood Technology Linnaeus UniversityVäxjöSweden Centre for Biomedical and Chemical Sciences School of ScienceAuckland University of TechnologyAucklandNew Zealand School of Science and Environmental Research Institute University of WaikatoPrivate Bag 3105HamiltonNew Zealand School of Biological Sciences and Te pūnaha Matatini University of AucklandAucklandNew Zealand

Despite a large number of studies examining the effects of abiotic stress factors on plants,the mechanistic explanations of drought-induced tree mortality remain inconclusive and even less is known about how multiple stressors *** role of non-structural carbohydrates(NSCs)in preventing or postponing drought mortality is gaining ***,we tested the role of NSCs in mitigating the effects of drought and salinity in New Zealand mangroves,Avicennia marina *** experimentally manipulated plant NSC levels,prior to subjecting them to combinations of drought and *** growth and survival rates were 2-and 3-fold higher in the high-NSC(h-NSC)group than in the low-NSC(L-NSC)group under high salinity and drought conditions,*** 12 weeks under high salinity-high drought conditions,the h-NSC group showed higher stem hydraulic conductivity(281±50 mmol cm^(−1)s^(−1)Mpa^(−1))compared with the L-NSC group(134±40 mmol cm^(−1)s^(−1)Mpa^(−1)).Although starch levels remained relatively constant,we found a 20%increase in soluble sugars in the stems of h-NSC group under high drought and high salinity in week 8 compared with week *** results suggest(i)an important role of NSCs in mitigating the effects of low soil water potential caused by drought and salinity,and(ii)sink-limited growth under conditions of combined salinity and drought.

关键词： non-structural carbohydrates Avicennia marina subsp.australasica drought and salt tolerance carbon limitation temperate mangroves

Impact of the biological definition of Alzheimer’s disease using amyloid, tau and neurodegeneration (ATN):what about the role of vascular changes,inflammation,Lewy body pathology?

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Translational Neurodegeneration 2018年第1期7卷 111-117页

作者： S.Gauthier h.Zhang K.p.ng T.A.pascoal p.Rosa-Neto McGill Center for Studies in Aging Douglas Mental Health Research InstituteMontrealCanada Department of Neurology The First Affiliated Hospital of Chongqing Medical UniversityChongqingChina Department of Neurology National Neuroscience InstituteSingaporeSingapore

Background:The NIA-AA research framework proposes a biological definition of Alzheimer’s disease,where asymptomatic persons with amyloid deposition would be considered as having this disease prior to ***:Notwithstanding the fact that amyloid deposition in isolation is not associated with dementia,even the combined association of amyloid and tau pathology does not inevitably need to dementia over age *** pathological factors may play a leading or an accelerating role in age-associated cognitive decline,including vascular small vessel disease,neuroinflammation and Lewy Body ***:Research should aim at understanding the interaction between all these factors,rather than focusing on them *** this will lead to a personalized approach to the prevention of brain aging,based on individual biological,genetic and cognitive profiles.

关键词： Alzheimer’s disease Diagnosis Treatment Biomarkers precision medicine Translational research Brain imaging Database analysis human volunteer cohorts

Superconvergence of a Galerkin FEM for higher-Order Elements in Convection-Diffusion problems

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Numerical Mathematics(Theory,Methods and Applications) 2014年第3期7卷 356-373页

作者： sebastian Franz h.-G.Roos Institut für Numerische Mathematik Technische Universit¨at Dresden01062 DresdenGermany

In this paper we present a first supercloseness analysis for higher-order Galerkin FEM applied to a singularly perturbed convection-diffusion *** a solution decomposition and a special representation of our finite element space,we are able to prove a supercloseness property of p+1/4 in the energy norm where the polynomial order p≥3 is odd.

关键词： Singular perturbation layer-adapted meshes superconvergence postprocessing

Co-substitution of zirconium and neodymium on hyperfine interactions and AC susceptibility of SrFe12O19 nanohexaferrites

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Journal of Rare Earths 2020年第3期38卷 265-273页

作者： M.A.Almessere Y.Slimani h.Güngünes A.Baykal Department of physics College of ScienceImam Abdulrahman Bin Faisal UniversityP.O.Box 198231441DammamSaudi Arabia Department of Biophysics Institute for Research&Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityP.O.Box 198231441DammamSaudi Arabia Department of physics Hitit University19030Cevre Yolu Bulvan-CorumTurkey Department of Nano-Medicine Research Institute for Research&Medical Consultations(IRMC)Imam Abdulrahman Bin Faisal UniversityP.O.Box 198231441DammamSaudi Arabia

This study presents the influence of Zn and Nd co-substitution on structure,morphology,AC susceptibility and ZFC-FC magnetizations of Sr nanohexaferrites(NhFs),SrFe12-x(Zn,Nd)xO19(0.0≤x≤1.0),which was produced by sol-gel *** powder patterns,scanning electron microscopy(SEM) and high-resolution transmission electron spectroscopy(hR-TEM) approve the synthesis of Sr M-type *** spectra show that Zn^2+ions occupy 2 b and 4f1 sites while Nd3+ions locate at 2 a,4f2 and 12 k *** magnetic properties of the produced Sr-NhFs were investigated also by ZFC-FC magnetizations and AC *** to the MFC-MZFC results(between 2 and 400 K),no blocking temperature was detected which indicates the ferromagnetic(FM) behavior of *** lower temperatures,a super-spin glass like behavior is *** AC susceptibility indicates that the magnetic interactions are improved due to the inclusion of low content(x=0.1) of Nd^3+and Zn^2+ions into the ***,with further increasing the Nd^3+and Zn^2+contents(x=0.9),the magnetic interactions are weakened.

关键词： Sr hexaferrites Rare earths Mossbauer spectroscopy AC susceptibility ZFC-FC

A longitudinal network analysis of social dynamics in rooks corvus frugilegus： repeated group modifications do not affect social network in captive rooks

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Current Zoology 2017年第5期63卷 379-388页

作者： palmyre h. BOUChERIE sebastian SOSA Cristian pASQUARETTA Valerie DUFOUR Institut pluridisciplinaire hubert Curien University of Strasbourg 23 rue Becquerel 67087 Strasbourg France Centre National de la Recherche Scientifique UMR 7178 67087 Strasbourg France Formerly affiliated with Grupo de Conducta Adaptativa e Interacci6n Psychology Faculty University of Barcelona 08035 Barcelona Spain

Numerous studies have investigated the remarkable variation of social features and the resulting structures across species. Indeed, relationships are dynamic and vary in time according to various factors such as environmental conditions or individuals attributes. however, few studies have investigated the processes that stabilize the structures within a given species, and the behavioral mechanisms that ensure their coherence and continuity across time. here, we used a dynamic actor-based model, RSiena, to investigate the consistency of the temporal dynamic of relationships of a group of captive rooks facing recurrent modifications in group composition （i.e., the loss and introduction of individuals）. We found that changes in relationships （i.e., formation and removal） followed consistent patterns regardless of group composition and sex-ratio. Rooks preferentially interacted with paired congeners （i.e., unpopular attachment） and were more likely to form rela- tionships with individuals bonded to a current social partner （i.e., ＂friends of friends＂, or triadic closure）. The sex of individuals had no effect on the dynamic of relationships. This robust behav- ioral mechanisms formed the basis of inter-connected networks, composed of sub-structures of in- dividuals emerging from the enmeshment of dyadic and triadic motifs. Overall, the present study reveals crucial aspects of the behavioral mechanisms shaping rooks social structure, suggesting that rooks live in a well-integrated society, going far beyond the unique monogamous pair-bond.

关键词： corvids preferential attachment social interactions social network analysis temporal dynamics triadic closure.

Composition Dependence of Surface phonon polariton Mode in Wurtzite InxGa1-xN （0 ≤ x ≤ 1） Ternary Alloy

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Chinese physics Letters 2008年第12期25卷 4378-4380页

作者： S. S. ng Z. hassan h. Abu hassan Nano-Optoelectronics Research and Technology Laboratory School of Physics Universiti Sains Malaysia 11800 Minden Pulau Pinang Malaysia

We present a theoretical study on the composition dependence of the surface phonon polariton （Spp） mode in wurtzite structure α-InxGa1-xN ternary alloy over the whole composition range. The Spp modes are obtained by the theoretical simulations by means of an anisotropy model. The results reveal that the Spp mode of α-InxGa1-xN semiconductors exhibits one-mode behaviour. From these data, composition dependence of the Spp mode with bowing parameter of-28.9 cm^-1 is theoretically obtained.

关键词： field emission molybdenum dioxide enhancement factor