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Exponentially Convergent Multiscale Finite Element Method

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Communications on Applied Mathematics and Computation 2024年第2期6卷 862-878页

作者： yifan Chen Thomas y.Hou yixuan Wang Applied and Computational Mathematics CaltechPasadena 91106USA

We provide a concise review of the exponentially convergent multiscale finite element method(ExpMsFEM)for efficient model reduction of PDEs in heterogeneous media without scale separation and in high-frequency wave *** ExpMsFEM is built on the non-overlapped domain decomposition in the classical MsFEM while enriching the approximation space systematically to achieve a nearly exponential convergence rate regarding the number of basis *** most generalizations of the MsFEM in the literature,the ExpMsFEM does not rely on any partition of unity *** general,it is necessary to use function representations dependent on the right-hand side to break the algebraic Kolmogorov n-width barrier to achieve exponential ***,there are online and offline parts in the function representation provided by the *** online part depends on the right-hand side locally and can be computed in parallel *** offline part contains basis functions that are used in the Galerkin method to assemble the stiffness matrix;they are all independent of the right-hand side,so the stiffness matrix can be used repeatedly in multi-query scenarios.

关键词： Multiscale method Exponential convergence Helmholtz's equation Domain decomposition Nonlinear model reduction

sANC Monte Carlo programs for small-angle Bhabha scattering

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Chinese Physics C 2024年第4期48卷 14-19页

作者： A.B.Arbuzov s.G.Bondarenko i.R.Boyko L.V.Kalinovskaya A.A.Kampf R.R.sadykov V.L.yermolchyk Bogoliubov Laboratory of Theoretical Physics JINRDubna141980 Russia Dzhelepov Laboratory of Nuclear Problems JINRDubna141980 Russia Dubna state University Dubna141982 Russia

Luminosity monitoring at e^(+)e^(−)colliders was investigated using sANC Monte Carlo event generator RenesANCe and integrator MCsANC for simulation of Bhabha scattering at low *** are presented for center-of-mass energies of the Z boson resonance and at 240 GeV for the conditions of typical luminosity *** is shown that bremsstrahlung events with extremely low electron scattering angles are relevant to match the precision tags of future electron-positron colliders.

关键词： luminosity Bhabha scattering QED Monte Carlo simulation

Quantum algorithms for matrix operations and linear systems of equations

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Communications in Theoretical Physics 2024年第3期76卷 100-112页

作者： Wentao Qi Alexandr i Zenchuk Asutosh Kumar Junde Wu school of Mathematical sciences Zhejiang UniversityHangzhou 310027China Federal Research Center of Problems of Chemical Physics and Medicinal Chemistry RAs ChernogolovkaRussia P.G.Department of Physics Gaya CollegeMagadh UniversityRampurGaya 823001India Harish-Chandra Research institute HBNIChhatnag RoadJhunsiPrayagraj 211019India Vaidic and Modern Physics Research Centre Bhagal BhimBhinmalJalore 343029India

Fundamental matrix operations and solving linear systems of equations are ubiquitous in scientific *** the‘sender-receiver’model,we propose quantum algorithms for matrix operations such as matrix-vector product,matrix-matrix product,the sum of two matrices,and the calculation of determinant and inverse *** encode the matrix entries into the probability amplitudes of the pure initial states of *** applying proper unitary transformation to the complete quantum system,the desired result can be found in certain blocks of the receiver’s density *** quantum protocols can be used as subroutines in other quantum ***,we present an alternative quantum algorithm for solving linear systems of equations.

关键词： matrix operation systems of linear equations ‘sender-receiver’quantum computation model quantum algorithm

simple and High-yield synthesis of a Thinner Layer of Graphenic Carbon from Coconut shells

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Journal of Renewable Materials 2024年第5期12卷 969-979页

作者： Retno Asih Haniffudin Nurdiansah Mochamad Zainuri Deni s.Khaerudini Angelinus T.setiawan A.y.Dias Pudji Untoro Ahmad sholihand Darminto Department of Physics Institut Teknologi Sepuluh NopemberSurabaya60111Indonesia Department of Material and Metallurgical Engineering Institut Teknologi Sepuluh NopemberSurabaya60111Indonesia Research Centre for Advanced Materials National Research and Innovation Agency(BRIN)Tangerang Selatan15314Indonesia PT.Graphene Nanomaterial Consulting Malang65141Indonesia Department of Physical Engineering Surya UniversityBanten15143Indonesia

Biomass has become of recent interest as a raw material for‘green’graphenic carbon(GC)since it promotes an environmentally friendly ***,we investigate a single pyrolysis route to synthesize GC from coconut shells which provides a simple method and can produce a high yield,thus being convenient for large-scale *** pyrolysis involves a stepped holding process at 350℃ for 1 h and at 650℃ or 900℃ for 3 *** GC sample resulted at the 900℃ pyrolysis has a thinner sheet,a less porous structure,a higher C/O ratio,and an enhanced electrical conductivity than those pyrolyzed at 650℃.The addition of Na3PO4 catalyst has no signiﬁ-cant effects on the GC structures obtained by this *** single pyrolysis route generates thinner GC sheets compared to the two-step heat treatment followed by the liquid phase exfoliation(LPE)***,the latter method offers a formation of clean samples with a porous or holey feature which has potential for advanced energy-storage applications.

关键词： Graphenic carbon biomass coconut shells pyrolysis synthesis route

Phase composition,conductivity,and sensor properties of cerium-doped indium oxide

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Nano Materials science 2024年第2期6卷 193-200页

作者： M.i.ikim G.N.Gerasimov V.F.Gromov O.J.ilegbusi L.i.Trakhtenberg N.N.semenov Federal Research Center for Chemical Physics of RAs MoscowRussia University of Central Florida OrlandoFLUSA Moscow institute of Physics and Technology(state University) DolgoprudnyMoscow RegionRussia Lomonosov Moscow state University MoscowRussia

The hydrothermal synthesis of in_(2)O_(3)and CeO_(2)–in_(2)O_(3)is investigated as well as the properties of sensor layers based on these *** the synthesis of in_(2)O_(3),intermediate products in(OH)_(3)and inOOH are formed,which are the precursors of stable cubic(c-in_(2)O_(3))and metastable rhombohedral(rh-in_(2)O_(3))phases,respectively.A transition from c-in_(2)O_(3)to rh-in_(2)O_(3)is observed with the addition of CeO_(2).The introduction of cerium into rh-in_(2)O_(3)results in a decrease in the sensor response to hydrogen,while it increases in composites based on c-in_(2)O_(3).The data on the sensor activity of the composites correlate with XPs results in which CeO_(2)causes a decrease in the concentrations of chemisorbed oxygen and oxygen vacancies in rh-in_(2)O_(3).The reverse situation is observed in composites based on c-in_(2)O_(3).Compared to in_(2)O_(3)and CeO_(2)–in_(2)O_(3)obtained by other methods,the synthesized composites demonstrate maximum response to H_(2)at low temperatures by 70–100℃,and have short response time(0.2–0.5 s),short recovery time(6–7 s),and long-term stability.A model is proposed for the dependence of sensitivity on the direction of electron transfer between in_(2)O_(3)and CeO_(2).

关键词： Cerium oxide indium oxide Nanocomposite Hydrothermal method Cubic phase Rhombohedral phase sensor response Conductivity Hydrogen Response/recovery time

Generation of polarized electron beams through self-injection in the interaction of a laser with a pre-polarized plasma

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High Power Laser science and Engineering 2024年第3期12卷 62-68页

作者： L.R.yin X.F.Li y.J.Gu N.Cao Q.Kong M.Büscher s.M.Weng M.Chen Z.M.sheng Key Laboratory of Nuclear Physics and ion-beam Application(MoE) Institute of Modern PhysicsDepartment of Nuclear Science and TechnologyFudan UniversityShanghaiChina state Key Laboratory of High Field Laser Physics Shanghai Institute of Optics and Fine MechanicsChinese Academy of SciencesShanghaiChina sANKEN(institute of scientific and industrial Research) Osaka UniversityOsakaJapan sichuan Research institute Shanghai Jiao Tong UniversityChengduChina Peter Grünberg institut(PGi-6) Forschungszentrum JülichJülichGermany institut für Laser-und Plasmaphysik Heinrich-Heine-Universität DüsseldorfDüsseldorfGermany Key Laboratory for Laser Plasmas(MoE) School of Physics and AstronomyShanghai Jiao Tong UniversityShanghaiChina Collaborative innovation Center of iFsA Shanghai Jiao Tong UniversityShanghaiChina Tsung-Dao Lee institute Shanghai Jiao Tong UniversityShanghaiChina

Polarized electron beam production via laser wakefield acceleration in pre-polarized plasma is investigated by particlein-cell *** evolution of the electron beam polarization is studied based on the Thomas±Bargmann±Michel±Telegdi equation for the transverse and longitudinal self-injection,and the depolarization process is found to be influenced by the injection *** the case of transverse self-injection,as found typically in the bubble regime,the spin precession of the accelerated electrons is mainly influenced by the ***,in the case of longitudinal injection in the quasi-1D regime(for example,*** et al.,***.110,135002(2013)),the direction of electron spin oscillates in the laser *** the electrons move around the laser axis,the net influence of the laser field is nearly zero and the contribution of the wakefield can be ***,an ultra-short electron beam with polarization of 99%can be obtained using longitudinal self-injection.

关键词： laser wakefield acceleration longitudinal self-injection particle-in-cell simulation polarized electron beam

等离子体技术制备具有亚微米颗粒结构的球化W-Cu伪合金微粉

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Transactions of Nonferrous Metals society of China 2024年第2期34卷 592-603页

作者： A.V.sAMOKHiN N.V.ALEKsEEV A.A.DOROFEEV A.A.FADEEV M.A.siNAysKiy i.D.ZAVERTiAEV y.V.GRiGORiEV institute of Metallurgy and Materials science Russian Academy of SciencesMoscow 119334Leninsky prospect 49Russian Federal scientific Research Center“Crystallography and Photonics” Russian Academy of SciencesMoscow 119334Leninsky prospect 59Russian

采用复杂多级方法研究并证实制备具有亚微米/纳米级内部结构的球形W-Cu复合微粉的可能性。首先,采用等离子体化学合成法制备具有核壳结构的W-Cu纳米粉末(W核及Cu壳)。然后,将W-Cu纳米粉末与蔗糖的水悬浮液进行喷雾干燥,形成25~63μm的微... 详细信息

采用复杂多级方法研究并证实制备具有亚微米/纳米级内部结构的球形W-Cu复合微粉的可能性。首先,采用等离子体化学合成法制备具有核壳结构的W-Cu纳米粉末(W核及Cu壳)。然后,将W-Cu纳米粉末与蔗糖的水悬浮液进行喷雾干燥,形成25~63μm的微粒,收率为50%。最后,用热等离子体射流处理由纳米粉末组成的微粒,形成致密的球形W-Cu颗粒。成品粉末的球化度为90%~95%,体积密度为8.1 g/cm^(3),流动性约为12 s/50 g,杂质中O、C和H的含量(质量分数)分别为0.7%、0.02%~0.2%和0.03%~0.05%。

关键词： W-Cu复合材料等离子体化学合成造粒等离子体球化纳米颗粒微粒微粉

subnormal serum Liver Enzyme Levels:A Review of Pathophysiology and Clinical significance

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Journal of Clinical and Translational Hepatology 2024年第4期12卷 428-435页

作者： Elham M.youssef George y.Wu Biochemistry Department National Research CenterCairoEgypt Department of Medicine Division of Gastroenterology-HepatologyUniversity of Connecticut Health CenterFarmingtonCTUSA

subnormal levels of liver enzymes,below the lower limit of normal on local laboratory reports,can be useful *** instance,subnormal levels of aminotransferases can be observed in vitamin B6 deficiency and chronic kidney *** alkaline phosphatase levels may indicate the presence of hypophosphatasia,Wilson's disease,deficiencies of divalent ions,or *** levels of gamma glutamyl transferase may be seen in cases of acute intrahepatic cholestasis,the use of certain medications,and in bone ***,subnormal levels of 5'-nucleotidase have been reported in lead poisoning and nonspherocytic hemolytic *** aim of this review is to bring attention to the fact that subnormal levels of these enzymes should not be ignored as they may indicate pathological conditions and provide a means of early diagnosis.

关键词： Transaminases Vitamin B6 Celiac disease Renal insufficiency Hepatolenticular Degeneration Crohn disease Malnutrition Clofibrate Bone diseases Lead poisoning Anemia Hemolytic

Competitive effect, but not competitive response, varies along a climatic gradient depending on tree species identity

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Forest Ecosystems 2024年第2期11卷 142-151页

作者： Teresa Valor Lluís Coll David i.Forrester Hans Pretzsch Miren del Río Kamil Bielak Bogdan Brzeziecki Franz Binder Torben Hilmers Zuzana sitková Roberto Tognetti Aitor Ameztegui Department of Agricultural and Forest sciences and Engineering(DCEFA) University of LleidaAv.Alcalde Rovira Roure 191E25198 LleidaSpain Joint Research Unit CTFC-AGROTECNiO-CERCA Ctra.Sant LlorençKm.225280SolsonaSpain swiss Federal institute of Forest Snow and Landscape Research WSLZürcherstrasse 1118903BirmensdorfSwitzerland CsiRO Land and Water GPO Box 1700CanberraACT2601Australia Chair of Forest Growth and yield science School of Life Sciences WeihenstephanTechnical University of MunichHans-Carl-Von-Carlowitz-Platz 285354FreisingGermany Forest Research Center INIA-CSICCtra.A Coruña Km 7.528040MadridSpain iuFOR Sustainable Forest Management Research InstituteUniversity of Valladolid&INIASpain Department of silviculture Institute of Forest SciencesWarsaw University of Life SciencesNowoursynowska 159/3402776WarsawPoland Bavarian state institute of Forestry(LWF) Hans-Carl-von-Carlowitz-Platz 1D-85354FreisingGermany National Forest Centre Forest Research InstituteT.G.Masaryka 2296001ZvolenSlovakia Faculty of Agricultural Environmental and Food SciencesFree University of Bozen-Bolzano Piazza Università1 I-39100Bolzano

Background: Understanding the role of species identity in interactions among individuals is crucial for assessing the productivity and stability of mixed forests over time. However, there is limited knowledge concerning the variation in competitive effect and response of different species along climatic gradients. in this study, we investigated the importance of climate, tree size, and competition on the growth of three tree species: spruce(Picea abies), fir(Abies alba), and beech(Fagus sylvatica), and examined their competitive response and effect along a climatic ***: We selected 39 plots distributed across the European mountains with records of the position and growth of 5,759 individuals. For each target species, models relating tree growth to tree size, climate and competition were proposed. Competition was modelled using a neighbourhood competition index that considered the effects of inter-and intraspecific competition on target trees. Competitive responses and effects were related to *** methods and information theory were used to select the best ***: Our findings revealed that competition had a greater impact on target species growth than tree size or climate. Climate did influence the competitive effects of neighbouring species, but it did not affect the target species? response to competition. The strength of competitive effects varied along the gradient, contingent on the identity of the interacting species. When the target species exhibited an intermediate competitive effect relative to neighbouring species, both higher inter-than intraspecific competitive effects and competition reduction occurred along the gradient. Notably, species competitive effects were most pronounced when the target species' growth was at its peak and weakest when growing conditions were far from their ***: Climate modulates the effects of competition from neighbouring trees on the target tree and not the susceptibility of th

关键词： Competition coefficient Competition reduction interspecific competition intraspecific competition Mixing effects Mixed species forest Neighbourhood models Plant-plant interactions