• 学术搜索
  • 科研智能体
    • Research Labs
    • AI 阅读
    • AI 文库
    • 深度研究
    • 学者亮点
  • 学术资源
    • AI2000
    • 期刊/会议
    • 学者库
    • 学术API
      MCP&Skill
    • 溯源树
    • 数据集
  • 知识沉淀
    • 学术空间
订阅小程序
旧版功能
aminer vip
开通会员低至0.73元/天
一次搞定AI科研
立即登录
  • English
  • 联系方式
    Rendiconti Lincei-scienze Fisiche E Naturali

    Rendiconti Lincei-scienze Fisiche E Naturali

    Journal中科院 综合性期刊 4区

    年发文量

    研究主题

    论文(1355)

    排序
    1The M-Truncated Fractional Isothermal Lane-Emden Equation: Analytical Solution and Physical Applications
    Mohamed I. Nouh,Emad A.-B. Abdel-Salam,Abaker A. Hassaballa

    We present an analytical solution for the isothermal gas sphere under the truncated M-fractional derivative (TMDISO), a two-parameter generalization of the classical Lane-Emden equation, introducing the derivative order α and truncation parameter β via the Mittag–Leffler function. Using a recursive power-series scheme accelerated by the Euler–Abel transformation and Padé approximants, we derive the M-truncated Emden function u( x;α ,β) and validate the method against the classical ( α = β = 1 ) solution to within | Δ u| < 10^ - 3for x ≤ 13 . Decreasing α or β systematically damps the growth of the Emden function and broadens the density distribution relative to the classical isothermal result. We apply the model to compute the visual extinction coefficient A_V as a function of projected impact parameter b for a Bonnor–Ebert-like geometry and fit the profiles to the near-infrared extinction map of Barnard 68. A systematic grid search over α∈[ 0.60,1.00] and β∈[ 0.60,1.00] (45 models, 9 × 5 grid) identifies a global minimum at α = 1.00, β = 0.70, yielding χ^2 = 7.394 (reduced χ^2 = 0.569 ), a 21 percent improvement over the classical model ( χ^2 = 9.363 ). The best-fit parameters ρ_c = 3.21 × 10^ - 19 gcm^ - 3 , n_c = 8.22 × 10^4 cm^ - 3 , and R = 18,410AU are fully consistent with independent dust-emission estimates for Barnard 68. The preference for α = 1.00 establishes that the improvement arises solely from the Mittag–Leffler truncation through Γ( β + 1)^2 in the series coefficients, encoding non-local physical processes such as sub-thermal turbulence or magnetic pressure support without invoking a fractional-order spatial derivative. A linear radial perturbation analysis yields a fractional Sturm–Liouville eigenvalue equation showing that all α < 1 configurations are dynamically unstable ( σ_0^2 < 0 ), while the best-fit case yields σ_0^2 = + 0.003889 and D = 14.045 , placing Barnard 68 precisely on the Bonnor–Ebert marginal stability threshold and independently corroborating the photometric best-fit parameters.

    2026
    引用
    AI阅读
    加入学术空间
    2Moho Mission to the Foundations of Continents: the ICDP DIVE Drilling Project in the Ivrea-Verbano Zone, Alps, Italy
    Mattia Pistone,Marco Venier,Luca Ziberna,Alberto Zanetti,György Hetényi,Andrew Greenwood,Donato Giovannelli,Simona Pierdominici,Virginia G. Toy,Alba S. Zappone,Silvia Pondrelli,Othmar Müntener

    Drilling has made it possible to explore the Earth’s interior, but still only to very shallow depths on the scale of the planet. Since 1960s, scientists have worked to reach the crust–mantle boundary known as the Moho. This boundary representing the foundations of continents is usually beyond the reach of our present-day technology. However, in some places on Earth, it is possible to reach the crust–mantle frontier without drilling to its original depth. The Ivrea-Verbano Zone in the Italian Alps is the prime target to explore the Moho at 2-km depth for the first time in the history of science. This is because the collision between tectonic plates generating the Alps brought the crust–mantle boundary along with a cohesive and preserved crustal section to such a shallow depth. Thus, under conditions of low pressure and temperature, our present-day drilling technology can put down a borehole to this depth. Based on the collaborative effort involving > 100 scientists worldwide, the ICDP (International Continental Scientific Drilling Program) DIVE (Drilling the Ivrea-Verbano zonE) project tackles key questions on the chemistry and architecture of the lithosphere, the geophysical signatures, insights into the deep biosphere, and the nature of the Moho. Here our perspective contribution presents new speculations about the Ivrea-Verbano Zone Moho transition zone based on the lithological column explored and sampled in the two boreholes and the petrophysical properties (rocks’ compressional wave velocities and densities) of the pre-Permian and Lower Permian lower crust lithologies.

    2026
    引用
    AI阅读
    加入学术空间
    3Dynamics of Recombination of Cesium and Iodide Ions Via the Negative Complex with a Xenon Atom
    Vyacheslav M. Akimov,Ekaterina V. Ermolova,Dmitrii B. Kabanov,Lev Yu. Rusin,Mikhail B. Sevryuk

    We explore and compare the dynamics of two transcomplex recombination reactions XeI– + Cs+ → CsI + Xe and XeCs+ + I– → CsI + Xe in the collision energy range from 0.1 to 2.5 eV. The reactions are simulated by the quasiclassical trajectory method on a semiempirical diabatic potential energy surface proposed in 2021. Recombination of an alkali cation M+ and a halide anion X– via the weakly bound negative ionic complex RX– with a neutral atom R has never been studied before. The results of trajectory simulation include the excitation and opacity functions, the distributions of the vibrational, rotational, and total internal energies of the cesium iodide molecule, and the distributions of the energy of the flying apart of the products CsI and Xe. All the principal dynamical characteristics of the two reactions mentioned turn out to be quite close. However, at almost all the collision energies, the cross section of ion recombination via XeI– is larger than the cross section of recombination via XeCs+. The main motivation for this work is the recently discovered peculiar deterministic chaos in the transcomplex recombination reactions RCs+ + Br– → CsBr + R with R = Kr, Xe, Hg.

    2026
    引用
    AI阅读
    加入学术空间
    4Phytochemical Composition and Bioherbicidal Potential of Aqueous Extracts from Three Wild Plants with Allelopathic Effect on the Germination and Growth of the Weed Portulaca Oleracea L.
    Mohamed El Arras,Abdelhamid Ennoury,Mostafa Lamhamdi, El Touhami Ouazzani Tayebi,Sara El Asri, Mariam El Idrissi El Berkani,Rachid Jbilou, Khalid Lairini,Mohamed Nhiri,Ahmed Bakrim

    Agricultural practices are increasingly challenged by biotic and abiotic stresses, which compromise crop yield and quality. Weeds, in particular, present a persistent problem, necessitating the exploration of sustainable alternatives to chemical herbicides. This study investigates the allelopathic effects of aqueous extracts from three wild plant species on common purslane (Portulaca oleracea L.). The research involved comprehensive phytochemical analyses and an evaluation of 19 germination and growth parameters. Notably, the Arisarum vulgare (O.Targ.Tozz). extract (AVE) exhibited strong inhibitory effects on purslane germination and growth, closely mirroring the action of glyphosate, a widely used synthetic herbicide. The inhibitory effects of AVE were attributed to its rich content of polyphenols, flavonoids, and condensed tannins. In contrast, extracts from Urtica urens (L.) (UUE) and Chamaemelum mixtum (L.) (CME) showed weaker and variable effects, with some parameters suggesting potential stimulatory responses under the tested conditions. The originality of this research lies in the novel selection of Arisarum vulgare (O.Targ.Tozz) and the thorough investigation of its herbicidal properties, offering new insights for sustainable weed management.

    2026
    引用
    AI阅读
    加入学术空间
    5Solitons, and Quantitative Analysis of the (2+1) Dimensional Boussinesq Equation in a Dispersive Medium
    Kalim U. Tariq,Nadia Cheemaa,Reem K. Alhefthi

    The (2+1)-dimensional Boussinesq equation describes complex wave propagation in shallow water with varying amplitudes, where dispersion and nonlinearity are important factors. The equation captures wave interactions in multiple dimensions. The Hirota bilinear method and the extended hyperbolic function approach are used to construct lump wave solutions, their interactions with periodic, strip and double-strip waves, and traveling wave solutions. Stability analysis is carried out to determine whether the solutions develop singularities or remain bounded. Bifurcation theory and sensitivity analysis for dynamical systems are applied to obtain phase diagrams of the governing model. Bifurcation theory of planar dynamical systems is also used to examine the model’s qualitative analysis. Three-dimensional graphical representations of the exact solutions show periodic features such dark V-shaped, singular bell-shaped, bright, unique periodic, and periodic soliton solutions. The findings provide analytical insight into the nonlinear dynamics and stability features of the model. Both approaches highlight the rich solution structure and its applications under various physical conditions.

    2026
    引用
    AI阅读
    加入学术空间
    立即登录,查看全部 1355 篇论文

    高被引作者

    作者引用发文
    Angelo Vulpiani7361
    Roberto Benzi7361
    Paolo Costantino2881
    Roberto Mattioli2881
    Maurizio Trovato2881
    Mohamed A. E. AbdelRahman2611
    Yunus Shukor26010
    R. Fantoni2421
    R Franciosi2421
    Mostafa M. El-Sheekh2378

    高产作者

    作者引用发文
    Corrado Battisti22023
    Luca Salvati19915
    Giovanni Amori10215
    Vincenzo Aquilanti19815
    Mohamed Fawzy Ramadan Hassanien18414
    Annibale Mottana4613
    Sandro Pignatti7913
    Luca M. Luiselli5412
    Fabio Attorre17212
    Tarek M. Galal13811

    相关期刊

    Rendiconti Lincei. Scienze Fisiche e Naturali
    Isotopes in environmental and health studies
    Journal of Environmental Radioactivity
    Applied Radiation and Isotopes
    Studia Quaternaria
    Atom Indonesia
    Journal of Radioanalytical and Nuclear Chemistry
    Natural Resources
    ARAB JOURNAL of NUCLEAR SCIENCES and APPLICATIONS
    CATRINA-THE INTERNATIONAL JOURNAL of ENVIRONMENTAL SCIENCES