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土壤温度对出苗前棉花生长的影响

沙漠与绿洲气象 2009年第1期3卷 58-60页

作者： g.nabi C.E.MULLINS 邹陈巴基斯坦国家农业研究中心土地资源研究项目英国阿伯丁大学植物和土壤科学系

土壤温度是调节植物生长和发育的一个重要变量。通过实验观测确定棉花出苗前不同土壤温度对根和芽的生长的影响。将棉花种在长300mm,直径50mm圆柱容器内,在土壤温度为20℃、32℃、38℃三种条件下生长192h。数据表明:在32℃时棉苗的根(17... 详细信息

土壤温度是调节植物生长和发育的一个重要变量。通过实验观测确定棉花出苗前不同土壤温度对根和芽的生长的影响。将棉花种在长300mm,直径50mm圆柱容器内,在土壤温度为20℃、32℃、38℃三种条件下生长192h。数据表明:在32℃时棉苗的根(173mm)和芽(152mm)最长,其次是20℃时(根130mm和芽82mm),在38℃时棉苗的根(86mm)和芽(50mm)最短。在棉苗生长192h以后,在20℃和38℃条件下的根系长度比在32℃条件下的根系分别短了20%和50%。38℃下棉苗根和芽的长度及干物质量最小。在棉苗生长180h以后,在20℃和38℃条件下的芽长比在32℃条件下的芽长分别短了44%和61%。棉苗在以上3个温度下生长模式相似:开始是线性生长,接着生长速率降低或停止生长。停止生长的时间随温度变化而变化,温度越高生长速率降低越快。土壤温度≥38℃时对出苗不利,因此棉花播种应在苗床土壤温度达到这个温度前完成。此外,在种子中储存的水分和营养物质损耗完之前,苗床应有足够的水分和营养供给种子生长。

关键词：线性生长根/苗生长土壤温度

Modification of polypropylene separator with multifunctional layers to achieve highly stable sodium metal anode

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Journal of Energy Chemistry 2025年第2期101卷 223-232页

作者： Aadil nabi Chishti Sikandar Iqbal Muhammad Ali Moazzam Ali Samia Aman Hamid Hussain Muhammad Yousaf Yinzhu Jiang Future Science Research Institute ZJU-Hangzhou Global Scientific and Technological Innovation Center Zhejiang University School of Materials Science and Engineering Zhejiang University School of Chemistry Zhejiang University

Separator modification is an effective approach to suppress dendrite growth to realize high-energy sodium metal batteries（SMBs） in practical applications,however,its success is mainly subject to surface ***,a separator with multifunctional layers composed of N-doped mesoporous hollow carbon spheres（HCS） as the inner layer and sodium fluoride（NaF） as the outer layer on commercial polypropylene separator（PP） is proposed（PP@HCS-NaF） to achieve stable cycling in *** the molecular level,the inner HCS layer with a high content of pyrrolic-N induces the uniform Na+flux as a potential Na+redistributor for homogenous deposition,whereas its hollow mesoporous structure offers nanoporous buffers and ion channels to regulate Na+ion distribution and uniform *** outer layer（NaF） constructs the NaF-enriched robust solid electrolyte interphase layer,significantly lowering the Na+ions diffusion *** from these merits,higher electrochemical performances are achieved with multifunctional double-layered PP@HCS-NaF separators compared with single-layered separators（***@HCS or PP@NaF） in *** Na‖Cu half-cell with PP@HCS-NaF offers stable cycling（280 cycles）with a high CE（99.6%）,and Na‖Na symmetric cells demonstrate extended lifespans for over 6000 h at 1 mA cm-2with a progressively stable overpotential of 9 ***,in Na‖NVP full-cells,the PP@HCS-NaF separator grants a stable capacity of ～81 mA h g-1after 3500 cycles at 1 C and an impressive rate capability performance(～70 mA h g-1at 15 C).

关键词： Enhanced cyclic stability Multifunctional layers NaF-enriched SEI layer Separator modification Sodium metal batteries

Analysis of Nuclear Structure Properties and Stellar β-decay Rates of Even–Even 106–120Zr Isotopes

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Research in Astronomy and Astrophysics 2025年第1期25卷 162-174页

作者： Abdul Kabir Jameel-Un nabi Syeda Anmol Rida Izzah Anwaar Noor-Ul Ain Raza Hamad Almujibah Department of Space Science Institute of Space Technology University of Wah Department of Civil Engineering College of EngineeringTaif University

The nuclear ground state properties of even–even106–120Zr nuclei have been investigated within the framework of the relativistic mean field （RMF） *** RMF model with density-dependent DDME2 and DDPC1interactions is utilized for the calculation of potential energy curves,the nuclear ground-state deformation parameters （β2）,neutron separation energies (S_nand S2n) and neutron skin thickness (rnp) of selected Zr ***,the β-decay properties of Zr isotopes were studied using the proton-neutron quasi-particle random phase approximation （pn-QRPA） *** include gamow–Teller strength distributions,β-decay half-lives and stellar electron emission/positron capture *** β2values computed from the RMF model were employed in the pn-QRPA model as an input parameter for the calculations of β-decay properties for even–even106–120Zr *** stellar rates were computed using the pn-QRPA framework with three different types of deformation *** at high temperature （T9≥2） and low density (ρYe≤10～7g cm-3) values,the sum of electron emission and positron capture rates has a sizeable contribution （with positive exponents） to the stellar rates.

关键词： (stars:) supernovae: individual (r-process) abundances astroparticle physics elementary particles nuclear reactions nucleosynthesis

An SPH Framework for Earthquake-Induced Liquefaction Hazard Assessment of geotechnical Structures

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Computer Modeling in Engineering & Sciences 2025年第1期142卷 251-277页

作者： Sourabh Mhaski g.V.Ramana Department of Civil Engineering Indian Institute of Technology DelhiNew Delhi110016India

Earthquake-induced soil liquefaction poses significant risks to the stability of geotechnical structures *** understanding of the liquefaction triggering,and the post-failure large deformation behaviour is essential for designing resilient *** present study develops a Smoothed Particle Hydrodynamics(SPH)framework for earthquake-induced liquefaction hazard assessment of geotechnical *** coupled flowdeformation behaviour of soils subjected to cyclic loading is described using the PM4Sand model implemented in a three-phase,single-layer SPH framework.A staggered discretisation scheme based on the stress particle SPH approach is adopted to minimise numerical inaccuracies caused by zero-energy modes and tensile ***,non-reflecting boundary conditions for seismic analysis of semi-infinite soil domains using the SPH method are *** numerical framework is employed for the analysis of cyclic direct simple shear test,seismic analysis of a level ground site,and liquefaction-induced failure of the Lower San Fernando *** agreement for liquefaction triggering and post-failure behaviour demonstrates that the SPH framework can be utilised to assess the effect of seismic loading on field-scale geotechnical *** present study also serves as the basis for future advancements of the SPH method for applications related to earthquake geotechnical engineering.

关键词： Earthquake seismic liquefaction stress particle PM4Sand smoothed particle hydrodynamics(SPH)

Projective Hilbert modules and sequential approximations

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Science China Mathematics 2025年第1期68卷 137-168页

作者： Lawrence g.Brown Huaxin Lin Department of Mathematics Purdue UniversityWest LafayetteIN 47907-2067USA Department of Mathematics East China Normal UniversityShanghai 200062China Department of Mathematics University of OregonEugeneOR 97405USA

We show that when A is a separable C^(*)-algebra,every countably generated Hilbert A-module is projective(with bounded module maps as morphisms).We also study the approximate extensions of bounded module *** the case where A is aσ-unital simple C^(*)-algebra with strict comparison,and every strictly positive lower semicontinuous affine function on quasitraces can be realized as the rank of an element in the Cuntz semigroup,we show that the Cuntz semigroup is equivalent to unitarily equivalent classes of countably generated Hilbert A-modules if and only if A has stable rank one.

关键词： projective Hilbert modules simple C^(*)-algebras sequential approximations

On Sawada-Kotera and Kaup-Kuperschmidt integrable systems

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Communications in Theoretical Physics 2025年第2期77卷 23-31页

作者： Metin gürses Asl| Pekcan Department of Mathematics Faculty of Science Bilkent University Department of Mathematics Faculty of Science Hacettepe University

To obtain new integrable nonlinear differential equations there are some well-known methods such as Lax equations with different Lax representations. There are also some other methods that are based on integrable scalar nonlinear partial differential equations. We show that some systems of integrable equations published recently are the M2-extension of integrable such scalar equations. For illustration, we give Korteweg–de Vries, Kaup-Kupershmidt, and SawadaKotera equations as examples. By the use of such an extension of integrable scalar equations, we obtain some new integrable systems with recursion operators. We also give the soliton solutions of the systems and integrable standard nonlocal and shifted nonlocal reductions of these systems.

关键词： recursion operator nonlocal reductions Hirota bilinear form soliton solutions .M2-extension recursion operator nonlocal reductions Hirota bilinear form soliton solutions

Stepping up after spinal cord injury:negotiating an obstacle during walking

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Neural Regeneration Research 2025年第7期20卷 1919-1929页

作者： Alain Frigon Charly g.Lecomte Department of Pharmacology-Physiology Faculty of Medicine and Health SciencesUniversitéde SherbrookeCentre de recherche du Centre Hospitalier Universitaire de SherbrookeSherbrookeQCCanada

Every day walking consists of frequent voluntary modifications in the gait pattern to negotiate *** spinal cord injury,stepping over an obstacle becomes *** over an obstacle requires sensorimotor transformations in several structures of the brain,including the parietal cortex,premotor cortex,and motor *** information and planning are transformed into motor commands,which are sent from the motor cortex to spinal neuronal circuits to alter limb trajectory,coordinate the limbs,and maintain *** spinal cord injury,bidirectional communication between the brain and spinal cord is disrupted and animals,including humans,fail to voluntarily modify limb trajectory to step over an ***,in this review,we discuss the neuromechanical control of stepping over an obstacle,why it fails after spinal cord injury,and how it recovers to a certain extent.

关键词： biomechanics locomotion neurophysiology obstacle negotiation spinal cord injury

ON THE gAUSSIAN KINEMATIC FORMULA OF *** AND ***

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Acta Mathematica Scientia 2025年第1期45卷 200-214页

作者： Joseph H.g.Fu Department of Mathematics University of GeorgiaAthensGA30602USA

We apply methods of algebraic integral geometry to prove a special case of the gaussian kinematic formula of *** idea,suggested already by Adler and Taylor,is to view the gKF as the limit of spherical kinematic formul... 详细信息

关键词： integral geometry kinematic formula probability density gaussian density

Damage analysis caused by ^(60)Co ions in functionally graded materials

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Defence Technology(防务技术) 2025年第2期44卷 248-256页

作者： Zübeyde Özkan Ugur gökmen Sema Bilge Ocak Department of Advanced Technologies Graduate School of Natural and Applied SciencesGazi UniversityAnkara06560Turkiye Department of Metallurgical and Materials Engineering Faculty of TechnologyGazi UniversityAnkara 06560Turkiye Basic and Engineering Sciences Central Laboratory Application and Research Center Gazi UniversityAnkara 06560Turkiye

Functionally graded composite/hybrid materials(FgCM/FgHCM)were produced by adding B_(4)C,TiO_(2),and B_(4)C+TiO_(2)ceramic materials at various ratios(0-50%)into the AA6082 *** analysis of the damage caused by^(60) ions'(1.173-1.1332 MeV)on the material was examined using the SRIM/TRIM Monte Carlo simulation *** the simulation,the following data regarding the atoms of the target materials were obtained:ion distribution,target ionization,total displacements,surface binding energy,lattice binding energy,and displacement *** the studied four materials,the one with the highest ion range value was found to be AA6082 with ***_(2)was found to be the reinforcement material that reduced the ion range the most in the *** to its high binding energy,B_(4)C reinforced AA6082+(0-50%)B_(4)C FgCM was found to have the least vacancy with 4782/ion.

关键词： SRIM/TRIM Damage analysis AA6082 ^(60)Co ion