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Strategies towards robust interpretations of in situ zircon Lu-Hf isotope analyses

Geoscience Frontiers 2020年第3期11卷 843-853页

作者： C.J.Spencer C.L.Kirkland n.M.w.Roberts n.J.Evans J.Liebmann School of Earth and Planetary Sciences The Institute for Geoscience Research(TIGeR)Curtin UniversityPerthAustralia Department of Geological Sciences and Geological Engineering Queen’s UniversityKingstonCanada Centre for Exploration Targeting-Curtin node The Institute for Geoscience ResearchSchool of Earth and Planetary SciencesCurtin UniversityPerthAustrali Geochronology and Tracers Facility British Geological SurveyNottinghamUK John de Laeter Centre GeoHistory Facility School of Earth and Planetary SciencesCurtin UniversityPerthAustralia

The combination of U-Pb and Lu-Hf compositions measured in zircon crystals is a remarkably powerful isotopic couplet that provides measures on both the timing of mineral growth and the radiogenic enrichment of the source from which the zircon *** U-Pb age documents the timing of zircon crystallization/recrystallization and Hf isotopes inform on the degree to which the host melt was derived from a radiogenic reservoir(*** mantle) versus an unradiogenic reservoir(*** continental crust),or some mixture of these *** ease of generating large quantities of zircon U-Pb and Lu-Hf data has been in large part facilitated by instrument ***,the dramatic increase in time constrained zircon Lu-Hf analyses in the Earth science community has brought to the fore the importance of careful data collection and reduction workflows,onto which robust geological interpretations may be *** this work,we discuss the fundamentals of Lu-Hf isotopes in zircon,which then allows us to provide a robust,accessible,methodology for the assessment of data ***,we discuss some novel techniques for:data visualization—that facilitates better transparency of data interpretation;integration of geographic information—that may reveal spatial trends where temporal trends were only apparent before;and some novel statistical evaluation tools—that may provide more rigorous interand intra-sample comparisons.

关键词： Zircon Geochronology Isotope geochemistry Lu-Hf isotopes Geostatistics Data visualization

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Calculation of Electron Swarm Parameters of SF_6/n_2 in a Uniform Field Using an Improved Monte Carlo Collision Simulation Method

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Plasma Science and Technology 2008年第1期10卷 39-42页

作者：汪沨 w.PFEIFFER n.KOUZICHInE 邱毓昌 E.KUFFEL 李肯立 School of Electrical and Information Engineering Hunan University Changsha 410082. China Technische Universitt Darmstadt 64283 Darmstadt Germany School of Electrical Engineering Xi'an Jiaotong University Xi'an 710049 China Department of Electrical Engineering and Computer Science University of Manitoba Winnipeg Canada School of Computor and Communication Huna University Changsha 410084 China

The electron swarm parameters of SF6/n2 are calculated in the present study using an improved Monte Carlo collision simulation method （MCS）. And some improved sampling techniques are also adopted. The simulation res... 详细信息

关键词： Monte Carlo collision simulation gas discharge swarm parameter

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The MYC transcription factor network： balancing metabolism, proliferation and oncogenesis

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Frontiers of Medicine 2018年第4期12卷 412-425页

作者： Patrick A. Carroll Brian w. Freie Haritha Mathsyaraja Robert n. Eisenman Division of Basic Sciences Fred Hutchinson Cancer Research Center 1100 Fairview Ave. N. Seattle WA 90109 USA

Transcription factor networks have evolved in order to control, coordinate, and separate, the functions of distinct network modules spatially and temporally. In this review we focus on the MYC network （also known as the MAX-MLX network）, a highly conserved super-family of related basic-helix-loop-helix-zipper （bHLHZ） proteins that functions to integrate extracellular and intracellular signals and modulate global gene expression. Importantly the MYC network has been shown to be deeply involved in a broad spectrum of human and other animal cancers. Here we summarize molecular and biological properties of the network modules with emphasis on functional interactions among network members. we suggest that these network interactions serve to modulate growth and metabolism at the transcriptional level in order to balance nutrient demand with supply, to maintain growth homeostasis, and to influence cell fate. Moreover, oncogenic activation of MYC and/or loss of a MYC antagonist, results in an imbalance in the activity of the network as a whole, leading to tumor initiation, progression and maintenance.

关键词： network transcription cancer MYC MAX MLX

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Isotopic Ages of the Penglai Group in the Jiaobei Belt and Their Geotectonic Implications

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Acta Geologica Sinica(English Edition) 1994年第4期68卷 417-433页

作者： w.R.Fitches C.J.n.Fletcher Institute of Earth Studies University College of WalesAberystwythSY23 3D B U KBritish Geological SurveyAberystwythSY 23 4BYU K

The Penglai Group in the Jiaobei Belt is the only remaining cover of the Archaean to Early Proterozoic crystalline basement in eastern Shandong. The ages of deposition of the Penglai Group and of its deformation and metamorphism have long been a subject of speculation. whole-rock Rb-Sr ages, illite-whole-rock pair Rb-Sr ages and illite K-Ar ages recently obtained from the Penglai Group slates are reported and interpreted in this paper. On the basis of structural and metamorphic studies coupled with analyses of illite crystallinity, XRD and SEM , a whole-rock age of 473±32 Ma (Ordovician) is interpreted as the time of termination of burial metamorphism experienced by the Penglai Group. Therefore, the age of the Penghai Group is older than Ordovician. The first-phase folding and syntectonic low greenschist facies metamorphism in the Penglai Group, i.e. the Penglai Movement, took place before 299±4 Ma B.P., i.e in the Late Carboniferous. The Penglai Movement that occurred in the Jiaobei Belt on the southern margin of the north China Plate is attributed to collision between the north China and Yangtze plates along the Jiaonan Collision Belt. This demonstrates that the continent-continent collision between the north China and Yangtze plates east of the Tan-Lu Fault Zone took place in the Late Carboniferous. The collision caused n-S compression and deformation in the southern margin belt of the north China Plate north of the Qinling-Dabieshan-Jiaonan Collision Belt.

关键词： illite age Jiaobei Belt north China Plate Yangtze Plate plate collision

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Extension/Compression-Controlled Complete Band Gaps in 2D Chiral Square-Lattice-Like Structures

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Acta Mechanica Solida Sinica 2018年第1期31卷 51-65页

作者： Y. L. Huang n. Gao w.Q. Chen R.H. Bao Department of Engineering Mechanics Zhejiang University Hangzhou 310027 China State Key Lab of CAD & CG Zhejiang University Hangzhou 310058 China Key Laboratory of Soft Machines and Smart Devices of Zhejiang Province Zhejiang University Hangzhou 310027 China Soft Matter Research Center Zhejiang University Hangzhou 310027 China

Achieving tunable band gaps in a structure by external stimuli is of great importance in acoustic applications. This paper aims to investigate the tunability of band gaps in square-lattice-like elastic periodic structures that are usually not featured with notable band gaps. Endowed with chirality, the periodic structures here are able to undergo imperfection-insensitive large deformation under extension or compression. The influences of geometric parameters on band gaps are discussed via the nonlinear finite element method. It is shown that the band gaps in such structures with curved beams can be very rich and, more importantly, can be efficiently and robustly tuned by applying appropriate mechanical loadings without inducing buckling. As expected, geometry plays a more significant role than material nonlinearity does in the evolution of band gaps. The dynamic tunability of band gaps through mechanical loading is further studied. Results show that closing, opening, and shifting of band gaps can be realized by exerting real-time global extension or compression on the structure. The proposed periodic structure with well-designed chiral symmetry can be useful in the design of particular acoustic devices.

关键词： Band gap Tunability Square-lattice-like periodic structure Chiral symmetry,Large deformation

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near-bed hydrodynamics associated with the entrainment of coarse particles at different protrusion heights

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Journal of Hydrodynamics 2022年第6期34卷 1067-1080页

作者： Yushu Xie Bruce w.Melville Asaad Y.Shamseldin Colin n.whittaker Yifan Yang Department of Civil and Environmental Engineering The University of AucklandAucklandNew Zealand School of Engineering The University of WaikatoHamiltonNew Zealand

This paper presents an investigation of near-bed hydrodynamics for a protruding coarse particle over a regular roughened *** laboratory experiments were undertaken at the threshold flow condition,which induced dislodgement of the protruding *** different protrusion heights,the experimental results show that the protruding particle substantially changed the spatial distributions of time-averaged velocities,turbulent kinetic energy,and Reynolds shear stress when compared with those obtained from a flat rough *** spatial distribution pattern of the flow characteristics shows a reasonable degree of similarity at different protrusion heights examined in this *** the target particle,a zone of low Reynolds shear stress was *** analysis was conducted along the main flow direction,at an elevation close to the top of the target particle.A prevalence of sweep(Quadrant 4)and outwards interaction(Quadrant 1)events were associated with the dislodgement of the protruding *** findings imply that the drag force related to strong streamwise velocities may play a more significant role in protruding particle entrainment than the shear stress.

关键词： Entrainment particle protrusion flow structure shear stress quadrant analysis

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neutron Star Composition in Strong Magnetic Fields

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Chinese Physics Letters 2003年第8期20卷 1238-1241页

作者：茅广军 V.n.Kondratyev A.Iwamoto 李祝霞吴锡真 w.Greiner I.n.Mikhailov JapanAtomicEnergyResearchInstitute TokaiNakaIbaraki319-1195Japan ChinaInstituteofAtomicEnergy POBox275(18)Beijing102413 InstitutflitTheoretischePhysikderJ.w.Goethe-Universit~t Postfach111932D-60054FrankfurtamMainGermany BogoliubovLaboratoryofTheoreticalPhysics JINRDubnaRussiaandCSNSM-IN2P3OrsayFrance

we study the neutron star composition in the presence of a strong magnetic field. The effects of the anomalous magnetic moments of both nucleons and electrons are investigated in relativistic mean field calculations for a β-equilibrium system. Since neutrons are fully spin polarized in a large field, generally speaking, the proton fraction can never exceed the field free case. An extremely strong magnetic field may lead to a pure neutron matter instead of a proton-rich matter.

关键词： neutrons

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Influence of alloying elements on microstructure and microhardness of Mg-Sn-Zn-based alloys

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Transactions of nonferrous Metals Society of China 2010年第12期20卷 2246-2252页

作者： w. L. CHEng S. PARK w. n. TAng B. S. YOU B. H. KOO School of nano ＆ Advanced Materials Engineering Changwon National University Changwon 641-773 South Korea Light Metals Research Group Korea Institute of Materials Science （KIMS） Changwon 641-831 South Korea

The phase evolution in （88%-91%）Mg-8%Sn-l%Zn-X （X=A1, Mn and/or Ce） system was analyzed via CALPHAD method and simulations were used in precise selection of the chemical composition. The influence of the addition of different alloying elements such as A1, Mn and Ce on the microstructure and microhardness of Mg-8%Sn-l%Zn-based alloys was investigated. Combined addition of A1 and Mn shows features distinct from separate addition of A1 or Mn. Additions of l%AI and l%Mn to base alloy result in the formation of massive A1-Mn phase in a-Mg matrix grains. Addition of Ce element can refme the second eutectic precipitates and form intermetallic compounds with Sn. Fine rod-like Sn-Ce phase presents mainly on the grain boundaries and plays a role in inhibiting grain growth. The effects of alloying elements on Vickers microhardness and indentation size effect of base alloy were examined.

关键词： magnesium alloys alloying elements CALPHAD method hardness indentation size effect

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Application of an amphipathic molecule at the niO_(x)/perovskite interface for improving the efficiency and long-term stability of the inverted perovskite solar cells

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Journal of Energy Chemistry 2023年第3期78卷 454-462,I0013页

作者： Guibin Shen Hongye Dong Fan Yang Xin Ren ng Xin Li Fen Lin Cheng Mu Key Laboratory of Advanced Light Conversion Materials and Biophotonics Department of ChemistryRenmin University of ChinaBeijing 100872China Solar Energy Research Institute of Singapore(SERIS) National University of SingaporeSingapore 117574Singapore State Key Laboratory of Materials Processing and Die&Mold Technology School of Materials Science and EngineeringHuazhong University of Science and TechnologyWuhan 430074HubeiChina Department of Chemistry National University of Singapore3 Science Drive 3Singapore 117574Singapore

The presence of defects and detrimental reactions at niO_(x)/perovskite interface extremely limit the efficiency performance and long-term stability of the perovskite solar cells(PSCs) based on niO_(x).Herein,an amphipathic molecule Triton X100(Triton) is modified on the niO_(x)*** hydrophilic chain of Triton as a Lewis base additive can coordinate with the ni3+on the niO_(x)surface which can passivate the interfacial defects and hinder the detrimental reactions at the niO_(x)/perovskite ***,the hydrophobic chain of Triton protrudes from the niO_(x)surface to prevent moisture from penetrating into the niO_(x)/perovskite ***,the niO_(x)/Triton-based devices(MAPbI3as absorbing layer) show superior moisture and thermal stability,retaining 88.4% and 64.3% of the initial power conversion efficiency after storage in air(40%-50% relative humidity(RH)) at 25 ℃ for 1070 h and in n2at 85℃ for 800 h,***,the efficiency increases from 17.59% to 19.89% because of the passivation defect and enhanced hole-extraction ***,the niO_(x)/Triton-based PSCs with Cs_(0.05)(MA_(0.15)FA_(0.85))_(0.95)Pb(I_(0.85)Br_(0.15))3perovskite as the light-absorbing layer also exhibits better moisture and thermal stability compared to the control devices,indicating the viability of our *** particular note,a champion PCE of 22.35% and 20.46% was achieved for small-area(0.1 cm^(2)) and large-area(1.2 cm^(2)) niO_(x)/Triton-based devices,respectively.

关键词： Perovskite solar cells niO_(x) Defect passivation Long-term stability Amphipathic molecule

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A note on Bell-Based Bernoulli and Euler Polynomials of Complex Variable

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Computer Modeling in Engineering & Sciences 2023年第4期135卷 187-209页

作者： n.Alam w.A.Khan S.Obeidat G.Muhiuddin n.S.Diab H.n.Zaidi A.Altaleb L.Bachioua Department of Basic Sciences Deanship of Preparatory YearUniversity of Ha’ilHa’il2440Saudi Arabia Department of Mathematics and natural Sciences Prince Mohammad Bin Fahd UniversityAl Khobar31952Saudi Arabia Department of Mathematics Faculty of ScienceUniversity of TabukTabuk71491Saudi Arabia

In this article,we construct the generating functions for new families of special polynomials including two parametric kinds of Bell-based Bernoulli and Euler *** fundamental properties of these functions are *** using these generating functions and some identities,relations among trigonometric functions and two parametric kinds of Bell-based Bernoulli and Euler polynomials,Stirling numbers are *** formulae for these polynomials are *** a partial derivative operator to these generating functions,some derivative formulae and finite combinatorial sums involving the aforementioned polynomials and numbers are also *** addition,some remarks and observations on these polynomials are given.

关键词： Bernoulli polynomials euler polynomials bell polynomials stirling numbers

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