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Geochemistry and petrogenesis of magnesian high-K granitoids from Bundelkhand Craton,Central India:New insights into crustal evolution

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Acta Geochimica 2025年第1期44卷 36-58页

作者： Shailendra K.Prajapati Meraj Alam Parashar Mishra Hemant Kumar Geological Survey of India Northern RegionLucknowUP 226024India Department of Geology Indira Gandhi National Tribal UniversityAmarkantakMP 484887India

Background The Bundelkhand Craton is significant for preserving the multiphase granitoids magmatism from Paleoarchean to Neoarchean *** consists of a variety of granite rocks,including TTGs,sanukitoids,and high-K *** study presents geochemical characteristics of high-silica(68.97 wt.%–73.99 wt.%),low-silica(58.73wt.%–69.94 wt.%),and high K_(2)O(2.77 wt.%–6.16 wt.%)contents of *** The data on Bundelkhand Craton’s granitic magmatism and geodynamics is not sufficiently *** data from this study will be used to further understand the origin,source,and petrogenesis of granitoid rocks and their implications for the evolution of *** Twenty-one samples were collected and analyzed for major,trace,and REE *** elements were measured using X-ray fluorescence spectrometry(XRF),and trace and REE elements were analyzed by *** procedures from the Geological Survey of India were *** The geochemical analysis presents high-silica(68.97-73.99 wt.%),low-silica(58.73-69.94 wt.%),and high K_(2)O(2.77-6.16 wt.%)contents in granitoids,classified as *** rocks are calcic to calcalkalic,magnesian,and range from peraluminous to metaluminous *** patterns showed strong LREE enrichment relative to HREEs,with prominent negative Eu anomalies corresponding to earlier plagioclase ***-element patterns revealed negative anomalies in Nb,Sr,P,and Ti and positive anomalies in *** The geochemical signatures attributed to the post-collisional magma generation and continental crustal *** studied rocks show A-type and A2-type lineage,suggesting they originated from the melting of continental crust during transitional/post-collisional tectonic *** formation of hybrid granitoids in the Bundelkhand Craton is connected to the fractionation of hybrid magmas in shallow-seated magma chambers during these tectonic processes.

关键词： Geochemistry Petrogenesis A-type granites Crustal evolution Bundelkhand craton

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HYDRODYNAMIC AND ELASTOHYDRODYNAMIC STuDIES OF A CYLINDRICAL JOuRNAL BEARING

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Journal of Hydrodynamics 2010年第2期22卷 155-163页

作者： ATTIA HILI Molka BOuAZIZ Slim MAATAR Mohamed FAKHFAKH Tahar HADDAR Mohamed Mechanics Modelling and Production Research unit (U2MP)National School of Engineers of Sfax(ENIS)BP.11733038sfaxTunisia

In this article,the effect of the bearing elastic deformation on the performance characteristics of a cylindrical journal bearing is *** variety of simulation models covers hydrodynamic（HD） and elastohydrodynamic（EHD） lubrication *** Reynolds equations governing the flow in the clearance space of the journal bearing are obtained by considering the effect of mass transfer across the fluid *** finite element method with an iteration scheme was employed to solve both the Reynolds equation and the three-dimensional elasticity equation representing the displacement field in the bearing *** converged solutions for the lubricant flow and elastic deformation vector are *** characteristics of the journal bearing are computed for HD and EHD *** simulation results show that the flexibility of bearing liner has a significant influence on the performance of a cylindrical journal ***,the elastic deformations of the bearing liner extend the pressure area in the bearing and increase the minimum film ***,dynamic coefficient,load capacity and attitude angle decrease.

关键词： Reynolds equation hydrodynamic(HD) and elastohydrodynamic(EHD) lubrication theories dynamic coefficients relative eccentricity deformation coefficient

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ACOuSTIC ANALYSIS OF HYDRODYNAMIC AND ELASTO-HYDRODYNAMIC OIL LuBRICATED JOuRNAL BEARINGS

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Journal of Hydrodynamics 2012年第2期24卷 250-256页

作者： BOuAZIZ Slim FAKHFAKH Tahar HADDAR Mohamed Dynamic of Mechanical Systems Research unit (uDSM) University of Sfax Mechanics Modelling and Production Research unit (u2mp) and National School of Engineers of Sfax (ENIS) BP.11733038University of Sfax

The purpose of the present paper is to investigate the effect of elastic deformation of bearing liner on the acoustic behavior of oil lubricated journal *** is performed for hydrodynamic（HD） and elasto-hydrodynamic （EHD） *** behavior and acoustical properties are investigated through an analysis of pressure fluctuation calculated from the Reynolds equation governing the flow in the clearance space of the journal *** is solved numerically using the finite difference method with the successive over relaxation *** elasto-hydrodynamic lubrication,the finite element method with in iteration scheme is adopted to solve both Reynolds equation and the three-dimensional elasticity equation representing the displacement field in the bearing *** results show that the sound pressure level of the bearing is markedly influenced by the flexibility of the bearing liner,the viscosity of lubricant and the load applied to *** analysis shows that the journal centre＇s orbit,from a disturbed position,converges to the static equilibrium position faster than EHD *** results of the present paper could aid in the design of low-noise rotor-bearing systems supported by oil lubricated journal bearings.

关键词： vibration amplitude pressure level lubricated bearing sound pressure

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A low power consumption control scheme:application to a piezostack-based active mount

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Frontiers of Mechanical Engineering 2013年第4期8卷 383-389页

作者： T.LOuKIL O.BAREILLE M.N.ICHCHOu M.HADDAR LTDS Ecolc Centrale de Lyon36 Avenue Guy de Collongue u2mp Ecole Nationale d'lngenieurs de Sfax

Piezostack-based active mounts have shown great efficiency for vibration control in a wide frequency *** this paper,we investigate the performances of the global semi-active control strategy presented by Ichchou et al.[1]for a control system consisting of an active mount and a supported *** control strategy allows extracting vibrations energy of the supported mass,storing it in accumulators to be reused for powering in part the actuators(two piezostacks).Consequently,energy needs are reduced versus good control performances comparable to those of the active control based on the negative velocity *** performances of the controller are evaluated in both frequency(transmitted force)and time(acceleration)domains which show that vibrations of the supported mass due to base excitations are efficiently attenuated with the proposed *** energetic analysis confirms the reduced energy requirement compared to the active scheme.

关键词： hybrid mount energy control piezoelectric harvesting

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Comprehensive Assessment of Transient Stability for Grid-Forming Converters Considering Current Limitations, Inertia and Damping Effects

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CSEE Journal of Power and Energy Systems 2025年第1期11卷 1-12页

作者： Jinlei Chen Qingyuan Gong Yawen Zhang Muhammad Fawad Sheng Wang Chuanyue Li Jun Liang School of Engineering Cardiff University Cardiff U.K. Compound Semiconductor Applications Catapult Newport U.K.

This paper presents a quantitative assessment of the transient stability of grid-forming converters, considering current limitations, inertia, and damping effects. The contributions are summarized in two main aspects: First, the analysis delves into transient stability under a general voltage sag scenario for a converter subject to current limitations. When the voltage sag exceeds a critical threshold, transient instability arises, with its severity influenced by the inertia and damping coefficients within the swing equation. Second, a comprehensive evaluation of these inertia and damping effects is conducted using a model-based phase-portrait approach. This method allows for an accurate assessment of critical clearing time (CCT) and critical clearing angle (CCA) across varying inertia and damping coefficients. Leveraging data obtained from the phase portrait, an artificial neural network (ANN) method is presented to model CCT and CCA accurately. This precise estimation of CCT enables the extension of practical operation time under faults compared to conservative assessments based on equal-area criteria (EAC), thereby fully exploiting the system's low-voltage-ride-through (LVRT) and fault-ride-through (FRT) capabilities. The theoretical transient analysis and estimation method proposed in this paper are validated through PSCAD/EMTDC simulations.

关键词： Transient analysis Power system stability Stability criteria Voltage control Damping Circuit faults Estimation Power quality Limiting Inductance

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Translational machinery and translation regulation in axon regeneration

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Neural Regeneration Research 2025年第5期20卷 1392-1394页

作者： Homaira Nawabi Stephane Belin univ.Grenoble Alpes InsermU1216Grenoble Institut NeurosciencesGrenobleFrance

Over the centuries,the regeneration field has been puzzled by the dual response of the central nervous system(CNS-brain,spinal cord,cranial nervesⅠandⅡ)and the peripheral nervous system(PNS that refers to all the nerves that innervate muscles,skin,organs,bones among others).Even Ramon y Cajal had noticed that an injury to the PNS often leads to axon regrowth,in contrast to the CNS.

关键词： nerves organs muscles

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Spectroscopic Study of the Late B-type Eclipsing Binary System AR Aurigae A and B:Towards Clarifying the Differences in Atmospheric Parameters and Chemical Abundances

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Research in Astronomy and Astrophysics 2025年第2期25卷 162-174页

作者： Yoichi Takeda 11-2 Enomachi Naka-ku Hiroshima-shi 730-0851 Japan

AR Aur A+B is a close binary of astrophysical interest because dissimilar surface compositions are reported between similar late B-type dwarfs. A new spectroscopic study on this system was carried out based on the disentangled spectra, in order to determine their atmospheric parameters and elemental abundances. The effective temperature and microturbulence（determined from the equivalent widths of Fe II lines） turned out to be(11,150 K,0.9 km s-1) and(10,650 K, 0.1 km s-1) for A and B, respectively. The chemical abundances of 28 elements were then derived while taking into account the non-LTE effect for Z ≤ 15 elements（Z: atomic number）. The following trends were elucidated for [X/H]（abundance of X relative to the Sun）:（1） Qualitatively, [X/H] shows a rough global tendency to increase with Z, with the gradient steeper for A than for B.（2） However, considerable dispersion is involved for A, since prominently large peculiarities are seen in specific elements reflecting the characteristics of HgMn stars（e.g., very deficient N, Al, Sc, Ni; markedly overabundant P, Mn）.（3） In contrast, the Z-dependence of[X/H] for B tends to be nearly linear with only a small dispersion. These observational facts may serve as a key to understanding the critical condition for the emergence of the chemical anomaly.

关键词： (stars:) binaries: spectroscopic stars: abundances stars: atmospheres stars: chemically peculiar stars: early-type stars: individual (AR Aur)

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Central role of altered phosphodiesterase 2-dependent signaling in the pathophysiology of cognition-based brain disorders

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Neural Regeneration Research 2025年第8期20卷 2302-2303页

作者： Asma Boulksibat Alessandra Tempio Barbara Bardoni Institut de Pharmacologie Moléculaire et Cellulaire CNRS UMR7275Inserm U1323ValbonneFrance

The second messengers 3',5'-cyclic adenosine monophosphate(cAmp)and 3',5'-cyclic guanosine monophosphate(cGmp)modulate molecular pathways that are involved in a large variety of cellular *** the brain,these processes include neurogenesis,neuronal differentiation,activation and function of microglia,and synaptic plasticity,finally resulting in memory formation.

关键词： formation processes finally

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LOG-CONCAVITY OF THE FIRST DIRICHLET EIGENFuNCTION OF SOME ELLIPTIC DIFFERENTIAL OPERATORS AND CONVEXITY INEQuALITIES FOR THE RELEVANT EIGENVALuE

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Acta Mathematica Scientia 2025年第1期45卷 143-152页

作者： Andrea COLESANTI Dipartimento di Matematica&Informdtica‘u.Dini’ Universitàdegli Studi di FirenzeViale Morgagni 67/A-50134FirenzeItaly

Given an open bounded subsetΩofℝn we consider the eigenvalue problem{Δu-(■u,■V)=-λvu,u>0inΩ,u=0 onδΩ,where V is a given function defined inΩandλV is the relevant *** determine sufficient conditions on V such that ifΩis convex,the solution u is *** also determine sufficient conditions ensuring thatλV,as a function of the setΩ,verifies a convexity inequality with respect to the Minkowski addition of sets.

关键词： eigenvalue log-concavity elliptic operator Brunn-Minkowski inequality convex body

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Concentration and retention of ascorbic acid,carotenoids,and sugars in fresh-cut lettuce in modified atmosphere packaging

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Horticultural Plant Journal 2025年第1期11卷 303-313页

作者： Jinita Sthapit Kandel Ivan Simko Ryan J.Hayes Beiquan Mou u.S.Department of Agriculture Agricultural Research ServiceSam Farr United States Crop Improvement and Protection Research Center1636 E.Alisal StreetSalinasCA93905USA u.S.Department of Agriculture Agricultural Research ServiceForage Seed and Cereal Research Unit3450 SW Campus WayCorvallisOR97331USA u.S.Department of Agriculture Agricultural Research ServiceSunflower and Plant Biology Research1616 Albrecht Blvd NFargoND58102USA

Fresh-cut lettuce is widely used in ready-to-eat salads sold in modified atmosphere packages (MAP).Even in MAP,fresh-cut lettuce has short shelf life that results in loss of *** cultivars exhibit genetic variation for shelf life in MAP,but their variation for nutrient retention is not *** accessions were evaluated for initial content of ascorbic acid (AsA),carotenoids,and sugars and their retention in *** with high content and/or good retention of one or more nutrients were *** romaine accession ‘Floricos’ had high levels of all the three *** with relatively high retention of all the three nutrients were ‘Salinas 88’,‘Siskiyou’,‘Solar’,SM09A,‘Romance’,and ‘Green Towers’.Romaine cultivars,‘Balady Barrage’,‘Green Towers’,and ‘Darkland’ had relatively high initial levels of all tested nutrients and good rate of their *** was no clear correlation between initial AsA/carotene concentrations and their retention rates,suggesting that besides content,retention of nutrients should also be a breeding target in a lettuce nutritional improvement *** analyses with the Pearson's correlation coefficient determined a negative relationship between tissue deterioration(AuDePS) and retention of all tested nutrients[r of-0.52 (Pugars],suggesting that an increase in tissue deterioration intensifies nutrient ***-sense heritability (H^(2)) across the experiments was0.15 for AsA,0.23 for total carotene,and 0.50 for total *** of germplasm with high nutrient content,extended shelf life and good nutrient retention provides valuable information for the lettuce industry and associated breeding programs.

关键词： Lettuce Shelf life Nutrient retention Ascorbic acid Carotene Sugars

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