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influence of high-temperature convective flow on viability of Scots pine needles(Pinus sylvestris L.)

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Journal of Forestry Research 2020年第5期31卷 1489-1497页

作者： i.G.Gette N.V.Pakharkova i.V.Kosov i.N.Bezkorovaynaya Siberian Federal University 79 SvobodnyKrasnoyarskRussia 660041 Sukachev institute of Forest SB RAS Federal Research Center “Krasnoyarsk Science Center of SB RAS”50 AkademgorodokKrasnoyarsk 660036Russia

During a forest fire,plants are affected by high temperatures causing *** the time of burning,it is difficult to record temperature changes in tree crowns and the associated effects on *** paper presents the results of modelling a high-temperature effect simulating a convective flow from a ground *** of the response was carried out by the parameters of rapid fluorescence(Fv/Fm,ETR),the state of the pigment complex,and the relative water content in the *** characterize the degree of heat endurance and short-term effects concerning thermal damage,saplings of Scots pine(Pinus sylvestris L.)were used at different times during the growing season(June,July,August,September).Experimental heating at 55℃ lasted for 5 and 10 *** were different levels of heat resistance by the *** in June show that heating of the saplings significantly suppressed *** July,August,and September,the photochemical quantum yield(Fv/Fm)was restored to 75%and 60%from the initial level after 5-and 10-min heating,*** electron transport rate(ETR)for saplings in September was restored to their initial level within 3 days after a short heat *** of the photosynthetic activity in needles was observed after a 5-min impact,but by the end of the study period,restoration had not reached control values.A longer heating of 10 min resulted in an irreversible suppression of photosynthesis and destruction of the photosynthetic apparatus,as evidenced by the decrease in the number of photosynthetic pigments.

关键词： Pinus sylvestris Heat stress Chlorophyll Fluorescence Forest fires

Heightened protein-translation activities in mammalian cells and the disease/treatment implications

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National Science Review 2020年第12期7卷 1851-1855页

作者： Chung-i Wu Haijun Wen State Key Laboratory of Biocontrol School of Life SciencesSun Yat-sen University

After cells divide,the new cells have to synthesize all the necessary cellular components in time for the next *** is a lower bound of time required for cells to double their *** mammalian cells,this lower bound may b...

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Performance enhancement of a DC-operated micropump with electroosmosis in a hybrid nanofluid:fractional Cattaneo heat flux problem

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Applied Mathematics and Mechanics(English Edition) 2022年第6期43卷 931-944页

作者： A.M.ALSHARiF A.i.ABDELLATEEF Y.A.ELMABOUD S.i.ABDELSALAM Department of Mathematics and Statistics College of ScienceTaif UniversityP.O.Box 11099Taif 21944Saudi Arabia Department of Applied Mathematics and Science Faculty of EngineeringNational University of Science and TechnologySeeb 111Sultanate of Oman Department of Mathematics College of Science and Arts at KhulisUniversity of JeddahJeddah 21589Saudi Arabia Department of Mathematics Faculty of ScienceAl-Azhar University(Assiut Branch)Assiut 71254Egypt Department of Basic Science Faculty of EngineeringThe British University in EgyptCairo 11837Egypt

The purpose of this investigation is to theoretically shed some light on the effect of the unsteady electroosmotic flow(EOF)of an incompressible fractional secondgrade fluid with low-dense mixtures of two spherical nanoparticles,copper,and *** flow of the hybrid nanofluid takes place through a vertical micro-channel.A fractional Cattaneo model with heat conduction is *** the DC-operated micropump,the Lorentz force is responsible for the pressure difference through the *** Debye-H¨ukel approximation is utilized to linearize the charge *** semianalytical solutions for the velocity and heat equations are obtained with the Laplace and finite Fourier sine transforms and their numerical *** addition to the analytical procedures,a numerical algorithm based on the finite difference method is introduced for the given domain.A comparison between the two solutions is *** variations of the velocity heat transfer against the enhancements in the pertinent parameters are thoroughly investigated *** is noticed that the fractional-order parameter provides a crucial memory effect on the fluid and temperature *** present work has theoretical implications for biofluid-based microfluidic transport systems.

关键词： hybrid nanofluid fractional Cattaneo heat flux Caputo-Fabrizio derivative

Anticorrosion properties and thin film composite deposition of ZnSiC-Cr_3C_2 coating on mild steel

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Defence Technology（防务技术） 2019年第1期15卷 106-110页

作者： A.A.Ayoola O.S.i.Fayomi A.P.i.Popoola Chemical Engineering Department Covenant University Chemical Metallurgical and Materials Engineering DepartmentTshwane University of Technology Mechanical Engineering Department Covenant University

This work considered the influence of Cr3 C2 particle loading on microstructure and mechanical properties of Zn-SiC-Cr3 C2 nanocomposite produced via electrocodeposition are investigated. The surface nature of the nanocomposite coatings were characterized using scanning electron microscope(SEM)coupled with the energy dispersive spectrometer(EDS). Abrasive wear behaviour and hardness property of Zn-SiC-Cr3 C2 nanocomposite produced were investigated using CERT UMT-2 multi-functional tribological tester and Dura Scan hardness tester. The corrosion property was evaluated through linear polarization approach. The result showed that the coatings exhibited good stability and Cr_3 C_2 nanocomposite loading significantly improved the micro structural performance, hardness property,wear resistance as well as corrosion resistance of the coatings.

关键词： Zn-SiC-Cr3C2 Electrodeposition Coatings Corrosion resistance Hardness

Hadron program at COMPASS

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Chinese Physics C 2010年第9期34卷 1375-1378页

作者： i.Uman Ludwig-Maximilians-Universitt München D-80799 Germany

The fixed target COMPASS experiment at CERN offers the opportunity to search for exotic mesons and glueball candidates in the light quark sector with unprecedented *** results from the 2008 data taken with an incoming negative hadron beam （190 GeV/c,mainly pions） on a liquid hydrogen target are *** detectors dedicated to hadron beam measurements have been *** give access to rare neutral and kaonic *** amplitude analysis which will allow to fit simultaneously diffractively and/or centrally produced resonances will be described and compared with those used in the CERN WA102 and BNL E852 experiments.

关键词： hadron spectroscopy light meson spectrum gluonic excitations exotic mesons hybrids

基于XeF(C-A)放大器的混合(固态/气态)超高功率飞秒激光系统(英文)

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光学精密工程 2011年第2期19卷 252-259页

作者： LOSEV V alekseev S iVANOV N KOVALCHUK B MiKHEEVL MESYATS G PANCHENKO Yu PUCHiKiN A RATAKHiN N YASTREMSKY A institute of High Current Electronics of Siberian Branch of Russian Academy of Sciences aveAkademichesky 2/3Tomsk 634055Russia Lebedev Physical institute of Russian Academy of Sciences Leninsky Prospekt53119991 Russia

提出了基于前端发生器和终端放大器,使用光泵浦XeF（C-A）激活介质的太瓦级混合激光器（THL-100）系统。前端发生器由长532 nm的连续激光泵浦的钛宝石飞秒脉冲振荡器,脉冲展宽机构,532 nm的脉冲激光泵浦的再生多通道放大器,衍射光栅压... 详细信息

提出了基于前端发生器和终端放大器,使用光泵浦XeF（C-A）激活介质的太瓦级混合激光器（THL-100）系统。前端发生器由长532 nm的连续激光泵浦的钛宝石飞秒脉冲振荡器,脉冲展宽机构,532 nm的脉冲激光泵浦的再生多通道放大器,衍射光栅压缩器和二次谐波发生器（KDP）组成。其光束输出参数为：脉冲持续时间50 fs,二次谐波（475 nm）辐射能量5 mJ。前端发生器以10 Hz的单脉冲模式工作。XeF（C-A）放大器由双高压脉冲发生器（线性变压器）,爆炸式阴极发射真空二极管,电子束注入系统,充满Xe的气室转换器和激光单元组成。高压发生器包括12个变压器,每个变压器有8个电容（40 nF）和火花隙,电容可以充电至100 kV。真空二极管中的电子束参数为：总电流300 kA,峰值电压550kV,脉冲持续时间约150 ns。穿透金属箔片到达Xe转换器的6个100 cm×12 cm电子束的总能量为67 kJ。激光系统通过泵浦能量的级联处理导致Xe2＊的快速形成,并在（172±5）nm连续辐射。真空紫外辐射通过CaF2窗口辐射到含有XeF2蒸汽和氮气缓冲气体的激光单元中,使XeF2光解,形成XeF＊准分子。由真空紫外辐射泵浦的放大器激活介质长110 cm,直径为24 cm。文中通过数值模拟给出了输出参数和第一实验结果,根据XeF（C-A）放大器参数模型和增益测量结果,得到的输出能量高达23 J,这意味着50 fs脉冲的峰值功率高达4060 TW。

关键词：混合激光器 XeF(C—A)放大器飞秒脉冲宽度电子束紫外转换器

Photoproduction of mesons off the deuteron:quasifree and coherent processes

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Chinese Physics C 2009年第12期33卷 1340-1344页

作者： i. Jaeglé Departmement of Physics University of Basel CH-4056 Basel Switzerland

Photoproduction of mesons off the deuteron has been investigated at a tagged photon beam of the Bonn ELSA accelerator with the combined Crystal Barrel - TAPS electromagnetic calorimeter for incident photon energies up to 2.5 GeV. The mesons have been detected in coincidence with recoil protons, neutrons and deuterons. This allow the measurement of meson production reactions off the quasifree nucleons bound in the deutron, as well as the coherent production off the deuteron. The comparison of quasifree proton reactions to free proton reactions can confirm or invalidate possible nuclear effects on the extracted cross section reactions. Furthermore the isospin composition of a resonance can be estimated from the comparison of quasifree proton and neutron reactions. The quasifree photoproduction of the η＇ and π°η mesons off nucleons and the coherent photoproduction of π°η--pairs off the deuteron are discussed.

关键词： quasifree coherent photoproduction η' π°η neutron proton deuteron

Multiphoton quantum dynamics of many-electron atomic and molecular systems in intense laser fields

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Chinese Physics B 2020年第8期29卷 115-126页

作者： Peng-Cheng Li Shih-i Chu Research Center for Advanced Optics and Photoelectronics Department of PhysicsCollege of ScienceShantou UniversityShantou 515063China Key Laboratory of intelligent Manufacturing Technology of MOE Shantou UniversityShantou 515063China Department of Chemistry University of KansasLawrenceKansas 66045USA

We present the recent new developments of time-dependent Schrödinger equation and time-dependent density-functional theory for accurate and efficient treatment of the electronic structure and time-dependent quantum dynamics of many-electron atomic and molecular systems in intense laser *** extend time-dependent generalized pseudospectral(TDGPS)numerical method developed for time-dependent wave equations in multielectron *** TDGPS method allows us to obtain highly accurate time-dependent wave functions with the use of only a modest number of spatial grid point for complex quantum dynamical *** usefulness of these procedures is illustrated by a few case studies of atomic and molecular processes of current interests in intense laser fields,including multiphoton ionization,above-threshold ionization,high-order harmonic generation,attosecond pulse generation,and quantum dynamical processes related to multielectron *** conclude this paper with some open questions and perspectives of multiphoton quantum dynamics of many-electron atomic and molecular systems in intense laser fields.

关键词： multiphoton ionization above-threshold ionization high-order harmonic generation attosecond pulse generation

Pseudospin symmetric solutions of the Dirac equation with the modified Rosen-Morse potential using Nikiforov-Uvarov method and supersymmetric quantum mechanics approach

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Chinese Physics B 2022年第5期31卷 107-112页

作者： Wen-Li Chen i B Okon School of intelligent Science and information Engineering Xi’an Peihua UniversityXi’an 710125China Theoretical Physics Group Department of PhysicsUniversity of UyoNigeria

Employing the Pekeris-type approximation to deal with the pseudo-centrifugal term,we analytically study the pseudospin symmetry of a Dirac nucleon subjected to equal scalar and vector modified Rosen-Morse potential including the spin-orbit coupling term by using the Nikiforov-Uvarov method and supersymmetric quantum mechanics *** complex eigenvalue equation and the total normalized wave functions expressed in terms of Jacobi polynomial with arbitrary spin-orbit coupling quantum number k are presented under the condition of pseudospin *** eigenvalue equations for both methods reproduce the same result to affirm the mathematical accuracy of analytical *** numerical solutions obtained for different adjustable parameters produce degeneracies for some quantum number.

关键词： Dirac equation modified Rosen-Morse potential Nikiforov-Uvarov method supersymmetric quantum mechanics approach