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Journal of Materials Science & Technology 2019年第6期35卷 1099-1107页

作者： X.Y. Jiao J. Wang c.F. Liu Z.P. Guo G.D. Tong S.L. Ma Y. Bi Y.F. Zhang S.M. Xiong School of Materials Science and Engineering Tsinghua University Beijing 100084 China State Key Laboratory of Automobile Safety and Energy Tsinghua University Beijing China china FAW Foundry co. Ltd. Changchun 130011. China

The fracture behavior of high-pressure die-cast hypereutectic(HPDc) Al-Si alloys was investigated using a high-resolution laboratory cT and sync.r.tron X-ray tomography with a particular focus on the influence of HPDc microstructure. results showed that microstructure of the alloy was mainly comprised of primary silicon particles(PSPs), Al dendrites, cu-rich phases and pores. Most of the coarse PSPs, cu-rich phases and pores were located in the center of the specimen. The rapid solidification of HPDc led to a heterogeneous microstructural feature. Elemental cu was enriched in the frontiers of solid-liquid interface, causing the formation of large size dendritic arms. The pores were formed in the interdendrites which endured high stress intensity under high applied stress. Microcracks were originated from pores and further connected cu-rich phases causing intergranular fracture. PSPs worked as obstacles causing piling-up dislocations in the phase interface. In the regions where large size of PSPs enriched in, PSPs ruptured rather than debonded from matrix, indicating transgranular fractures of PSPs. Microcracks originated around pores and PSPs tended to converge on the main cracks to decrease the energy required for crack propagation.

关键词： Hypereutectic Al-Si alloy Primary silicon particles Porosity Fracture morphology High pressure die casting

墨西哥两个水文封闭型高原湖泊沉积物记录到受人类活动影响的敏感度

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AMBIO－人类环境杂志 2005年第6期34卷 464-470页

作者： Sarah J.Davies Sarah E.Metcalfe Fernando Bernal-Brooks Arturo chacón-Torres John G.Farmer A.B.MacKenzie Anthony J.newton 李四海 Aberystwyth威尔士大学地理和地球科学研究所第四纪环境变化科研小组诺丁汉大学地理学院 de Investigaciones Sobre rec.r.os Naturales研究所爱丁堡大学地球科学学院苏格兰大学环境研究中心

本文提供了墨西哥中部两个高原湖泊近期环境快速变化的证据。从济拉温湖(米却肯州)和胡安艾卡特兰湖(哈利斯科州)获得了多个沉积物钻芯,利用^(210)Pb和^(14)c,以及火山灰年代测定法确定年代,进行了硅藻组合、磁化率和金属含量分析。在... 详细信息

本文提供了墨西哥中部两个高原湖泊近期环境快速变化的证据。从济拉温湖(米却肯州)和胡安艾卡特兰湖(哈利斯科州)获得了多个沉积物钻芯,利用^(210)Pb和^(14)c,以及火山灰年代测定法确定年代,进行了硅藻组合、磁化率和金属含量分析。在殖民时期,两盆地内有汇水区被扰动的迹象,但这两个地方最显著的特征是,最近20年来硅藻种群组合特征的快速变化,这指示着富营养化的开始。尽管在胡安艾卡特兰湖还没获得这方面的任何数据,但济拉温湖的湖泊学数据支持这种解释。古湖泊学在跟踪近期变化过程,特别是在缺乏常规湖泊监测计划的情况下是一种强有力的工具。这些湖泊对汇水区的开发变化特别敏感,必须在将来的流域管理中予以考虑。

关键词：湖泊沉积物高原湖泊人类活动影响敏感度墨西哥封闭型水文 ^210Pb 快速变化硅藻组合

An Alternative Three-phase Transmission Lines Model in Phase Domain

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Energy and Power Engineering 2013年第4期5卷 1490-1496页

作者： c. G. c.r.alho S. Kurokawa J. Pissolato Universidade Estadual de campinas (Unicamp) Electrical Engineering Department Campinas Brazil Universidade Estadual Paulista (Unesp) Electrical Engineering Department Ilha Solteira Brazil

The objective of this paper is to show an alternative model of a non-transposed three-phase transmission line with a vertical symmetry plane in phase domain. Due the line physical characteristics, it can be represented by a system consisting of a single?phase and a two-phase line. In this system, the equations describing the behavior of the values in single-phase line terminals are known, while the equations for two-phase line to be obtained. Using a transformation matrix written explicitly acc.r.ing to three-phase line parameters, it is possible to obtain the c.r.ents and voltages in phase domain of two-phase line. Then, modal values of three-phase line are converted into phase domain and thus obtain the analytical model for this line. To verify the performance of this model, it was used to simulate the energization of a 440 kV three-phase line and the results were compared to results obtained using a classical model.

关键词： Transmission Lines Frequency Dependence Modal representation Transformation Matrix newton-raphson Phase Domain

流变学流体的蠕动传输:食道中食物块的运动模型

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应用数学和力学 2012年第3期33卷 303-319页

作者： J·c·密斯拉 S·麦蒂海治斯克沙欧阿纳山德汉大学数学系布巴内斯瓦尔751030印度印度科技学院医学和技术系卡拉普尔721302印度

研究食道中蠕动传输的流体力学.对任意的波形和任意的管道长度,建立起流变学流体蠕动传输的数学模型.用粘性流体的Ostwald-de Waele幂定律,描述非newton流体的流动特性.解析公式化模型,详细且精确地给出食物块在食道中蠕动传输相关的一... 详细信息

研究食道中蠕动传输的流体力学.对任意的波形和任意的管道长度,建立起流变学流体蠕动传输的数学模型.用粘性流体的Ostwald-de Waele幂定律,描述非newton流体的流动特性.解析公式化模型,详细且精确地给出食物块在食道中蠕动传输相关的一些重要性质.分析中应用了润滑理论,本研究特别适合于reynolds数不大的情况.将食道看作环形的管道,通过食道壁周期性的收缩来传输食物块.就单个波和周期性收缩一组波的传播,研究与传输过程有关变量的变化,如压力、流速、食物颗粒轨迹以及流量等.局部压力的变化,对流变指数n有着高度的敏感性.研究结果清晰地表明,食物块在食道中蠕动传输时,newton流体或流变学流体构成的连续流体,以组合波传播比大间隔单波传播,传输效率要高得多.

关键词：非newton流体食物块食道蠕动传输逆向流单波组合波颗粒轨迹

rotating Lepton Model of Pions and Kaons: Mechanics at fm Distances

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Journal of Applied Mathematics and Physics 2022年第9期10卷 2805-2819页

作者： constantinos G. Vayenas Dionysios Tsousis Dimitrios Grigoriou Konstantinos Parisis Elias c. Aifantis University of Patras Patras Greece Academy of Athens Athens Greece Stanford University Stanford USA Aristotle University of Thessaloniki Thessaloniki Greece Michigan Technological Institute Houghton USA Friedrich-Alexander University Erlangen-Nürnberg Germany

The present article is a continuation of a recently published paper [1] in which we have modeled the composition and structure of neutrons and other hadrons using the rotating Lepton Model (rLM) which is a Bohr type model employing the relativistic gravitational attraction between three ultrafast rotating neutrinos as the centripetal force. The rLM accounts for special relativity and also for the De Broglie equation of quantum mechanics. In this way this force was shown to reach the value of the Strong Force while the values of the masses of the rotating relativistic neutrinos reach those of quarks. Masses computed for twelve hadrons and bosons are in very close (~2%) agreement with the experimental values. Here we use the same rLM approach to describe the composition and structure and to compute the masses of Pions and Kaons which are important zero spin mesons. contrary to hadrons and bosons which have been found via the rLM to comprise the heaviest neutrino eigenmass m3, in the case of mesons the intermediate neutrino mass eigenstate m2 is found to play the dominant role. This can explain why the lowest masses of mesons are generally smaller than those of hadrons and bosons. Thus in the case of Pions it is found that they comprise three rotating m2 mass eigenstate neutrinos and the computed mass of 136.6 MeV/c2 is in good agreement with the experimental value of 134.977 MeV/c2. The Kaon structure is found to consist of six m2 mass eigenstate neutrinos arranged in two parallel pion-type rotating triads. The computed Kaon mass differs less that 2% from the experimental K± and K°values of 493.677 MeV/c2 and 497.648 MeV/c2 respectively. This, in conjunction with the experimentally observed decay products of the Kaons, provides strong support for the proposed K structure.

关键词： Pions and Kaons-Structure and Masses Gravitational Bohr-de Broglie-newton-Einstein Type Models rotating Lepton Model (rLM) Hadronization Neutrino Masses Special relativity Gravitational Force Quantum Mechanics

The genomes of medicinal skullcaps reveal the polyphyletic origins of clerodane diterpene biosynthesis in the family Lamiaceae

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Molecular Plant 2023年第3期16卷 549-570页

作者： Haixiu Li Song Wu ruoxi Lin Yiren Xiao Ana Luisa Malaco Morotti Ya Wang Meytal Galilee Haowen Qin Tao Huang Yong Zhao Xun Zhou Jun Yang Qing Zhao Angelos K.Kanellis cathie Martin Evangelos c.Tatsis National Key Laboratory of Plant Molecular Genetics CAS Center for Excellence in Molecular Plant SciencesShanghai Institute of Plant Physiology and EcologyChinese Academy of SciencesShanghai 200032China University of chinese Academy of Sciences Beijing 100049China Novogene Bioinformatics Institute BeijingChina Shanghai Key Laboratory of Plant Functional Genomics and resources Shanghai Chenshan Botanical GardenShanghai Chenshan Plant Science Research CenterChinese Academy of SciencesShanghai 201602 Group of Biotechnology of Pharmaceutical Plants Lab.of PharmacognosyDepartment of Pharmaceutical SciencesAristotle University of Thessaloniki54124 ThessalonikiGreece John Innes centre Norwich NR47UHUK cEPAMS-cAS-JIc centre of Excellence for Plant and Microbial Sciences Shanghai 200032China

The presence of anticanc.r.clerodane diterpenoids is a chemotaxonomic marker for the traditional chinese medicinal plant Scutellaria barbata,although the molecular mechanisms behind clerodane biosynthesis are ***,we report a high-quality assembly of the 414.98 Mb genome of *** into 13 *** phylogenomic and biochemical data,we mapped the plastidial metabolism of kaurene(gibberellins),abietane,and clerodane diterpenes in three species of the family Lamiaceae(Scutellaria barbata,Scutellaria baicalensis,and Salvia splendens),facilitating the identification of genes involved in the biosynthesis of the clerodanes,kolavenol,and *** show that clerodane biosynthesis evolved through recruitment and neofunctionalization of genes from gibberellin and abietane *** the assumed monophyletic origin of clerodane biosynthesis,which is widespread in species of the Lamiaceae,our data show distinct evolutionary lineages and suggest polyphyletic origins of clerodane biosynthesis in the family *** study not only provides significant insights into the evolution of clerodane biosynthetic pathways in the mint family,Lamiaceae,but also will facilitate the production of anticanc.r.clerodanes through future metabolic engineering efforts.

关键词： Scutellaria barbata genome clerodane diterpenoids biosynthesis specialized metabolism evolution

Probing the Variation of reverberation Lags along with X-ray Flux in the AGN Mrk 704

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research in Astronomy and Astrophysics 2023年第3期23卷 75-84页

作者： K.Sriram Deblina Lahiri Vivek K.Agrawal D.Nour c.S.choi Department of Astronomy Osmania UniversityHyderabad 500007India Korea Astronomy and Space Science Institute Daejeon 34055Republic of Korea Space Astronomy Group ISITE CampusU.R.Rao Satellite CentreOuter Ring Road.MarathahallBangalore 560037India Department of Physics Faculty of ScienceAl Baath UniversityHomsSyria

Understanding the variation of lags with respect to the X-ray flux is important to explore the geometry of the inner region of the ac.r.tion disk in *** performed frequency-lag,energy–lag and spec.r.l studies for two sets of observations,in order to investigate the variations in lags with respect to X-ray flux in the AGN source Mrk 704 using the XMM-newton *** divided one of the light c.r.es into two sections which were noticed to exhibit a flux *** frequency-lag spec.r. in different energy domains revealed that reverberation(soft)lags varied along with the *** the first time,we show that the blurred reflection model can consistently explain the soft excess observed in the X-ray spec.r. for this *** fluxes of soft(i.e.,reflection)and hard components were noted to vary by~18%and~9%respectively,across the *** soft lag amplitude was found to be larger at the high flux state than the amplitude at the low flux *** importantly,we found that both frequency-lag and energy–lag spec.r. do not display significant variation between two observational data sets despite a flux variation of 43%.This phenomenon cannot be explained by the reflection model because the soft lag amplitudes must be larger in the high flux *** probable scenario is that,in the low flux state,the obsc.r.ng cloud delays the reflected soft photons which increases the soft lag amplitude.

关键词： reflected c.r.ng AGN

Effects of Pressure Stress Work and Viscous Dissipation in Mixed convection Flow Along a Vertical Flat Plate

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Journal of Mathematics and System Science 2013年第3期3卷 115-121页

作者： A.S. Bhuiyan J. M. Alam M. r. Biswas Department of Mathematics Brock University St.Catharines Ontario L2S 3A1 Canada Department of Mathematics and Sat&ties Memorial University St. John "s NL A1C 5S7 Canada

The Effects of pressure stress work and viscous dissipation in mixed convection flow along a vertical fiat plate have been investigated. The results are obtained by transforming the governing system of boundary layer equations into a system of non-dimensional equations and by applying implicit finite difference method together with newton＇s linearization approximation. Numerical results for different values of pressure stress work parameter, viscous dissipation parameter and Prandtl number have been obtained. The velocity profiles, temperature distributions, skin friction co-efficient and the rate of heat transfer have been presented graphically for the effects of the aforementioned parameters.

关键词： Mixed convection viscous dissipation pressure stress work.

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关于动量守恒定律的讨论

西南民族大学学报（自然科学版） 2004年第6期30卷 856-858页

作者：邓发明康定民族师范专科学校数学系四川康定626001

介绍了动量守恒定律建立的历史过程,对动量守恒定律进行了讨论,并对动量守恒定律存在的内在实质作了探讨.

关键词：动量守恒定律实质历史过程存在

TrANSFOrM DOMAIN cONJUGATE GrADIENT ALGOrITHM FOr ADAPTIVE FILTErING

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Journal of Elec.r.nics(china) 2000年第1期17卷 69-76页

作者： S.c.chan T.S.Ng Department of Elec.r.cal and Elec.r.nic Engineering The University of Hong Kong Pokfulam Road Hong KongDepartment of Electrical and Electronic EngineeringThe University of Hong Kong Pokfulam Road Hong Kong

This paper proposed a new normalized transform domain conjugate gradient algorithm (NT-cGA), which applies the data independent normalized orthogonal transform technique to approximately whiten the input signal and utilises the modified conjugate gradient method to perform sample-by-sample updating of the filter weights more efficiently. Simulation results illustrated that the proposed algorithm has the ability to provide a fast convergence speed and lower steady-error compared to that of traditional least mean square algorithm (LMSA), normalized transform domain least mean square algorithm (NT- LMSA), Quasi-newton least mean square algorithm (Q-LMSA) and time domain conjugate gradient algorithm (TD-cGA) when the input signal is heavily coloured.

关键词： Adaptive filtering conjugate gradient algorithm Orthogonal transform channel equalization Echo cancellation