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Rotating effects on the photoionization cross-section of a 2D quantum ring

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communications in Theoretical Physics 2024年第10期76卷 153-159页

作者： carlos Magno O Pereira Frankbelson dos s Azevedo Luís Fernando c Pereira Edilberto O silva Departamento de Física Universidade Federal do Maranh?o

In this article, we investigate the nonrelativistic quantum motion of a charged particle within a rotating frame, taking into account the Aharonov–Bohm(AB) effect and a uniform magnetic field. Our analysis entails the derivation of the equation of motion and the corresponding radial equation to describe the system. solving the resulting radial equation enables us to determine the eigenvalues and eigenfunctions, providing a clear expression for the energy levels. Furthermore,our numerical analysis highlights the substantial influence of rotation on both energy levels and optical properties. specifically, we evaluate the photoionization cross-section with and without the effects of rotation. To elucidate the impact of rotation on the photoionization process of the system, we present graphics that offer an appealing visualization of the intrinsic nature of the physics involved.

关键词： Aharonov-Bohm effect photoionization cross-section quantum ring rotating effect

classification of Rings Associated with the Genus of clean Graphs

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Algebra colloquium 2024年第3期31卷 451-466页

作者： V.Ramanathan c.selvaraj Aaqib Altaf s.Pirzada Department of Mathematics Periyar UniversitySalem 636011Tamil NaduIndi Department of Mathematics University of KashmirHazratbalSrinagarKashmirIndia

Let R be a ring(not necessarily commutative)with identity 1 and let cL(R)be its clean *** this paper,we investigate the genus number of the compact Riemann surface in which cL(R)can be embedded and explicitly determine all commutative rings R(up to isomorphism)such that cL(R)has genus at most *** is shown that for any Artinian ring R,cL(R)is a projective graph if and only if R is isomorphic to ***,we determine all isomorphism classes of commutative rings whose clean graphs have crosscap two.

关键词： clean graph commutative ring planar graph genus crosscap

cr-induced fusion reactions to synthesize superheavy elements

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Nuclear science and Techniques 2024年第5期35卷 122-130页

作者： s.Madhu H.c.Manjunatha N.sowmya B.M.Rajesh L.seenappa R.s.susheela Department of Physics R V College of EngineeringBangalore 560074India Visvesvaraya Technological University BelagaviKarnataka 590018India Department of Physics Government First Grade CollegeSrinivasapurKarnataka 563135India Department of Physics Government First Grade CollegeDevanahallyKarnataka 562110India Department of Physics Government First Grade CollegeMulbagalKarnataka 563131India Department of Physics Government First Grade collegeNanjangudOoty RoadMysore 571301India

We investigated ^(50,52-54)cr-induced fusion reactions for the synthesis of the superheavy element in the 104≤Z≤122 *** cross sections produced in this investigation using ^(54)cr projectiles were compared with those obtained in prior *** estimated cross sections from this analysis are consistent with the findings of prior *** the current study,the predicted cross section was found to be 42fb at 236 MeV for ^(53)cr+^(243)Am,23.2 fb at 236 MeV for ^(54)cr+^(247)cm,95.6 fb at 240 MeV for ^(53)cr+248Bk,and 1.33 fb at 242 MeV for ^(53)cr+***,these projected cross sections with excitation energy and beam energy will be useful in future cr-induced fusion reaction investigations.

关键词： Fusion cross sections compound nucleus formation probability survival probability Evaporation residue cross sections

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Modelling the brittle rock failure by the quaternion-based bonded-particle model in DEM

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Rock Mechanics Bulletin

Rock Mechanics Bulletin 2024年第2期3卷 87-95页

作者： Tao Zhao philip E.F.collins Department of civil and Environmental Engineering Brunel University LondonLondonUB83PHUnited Kingdom

This paper presents an investigation of brittle rock failure by the quaternion-based bonded-particle model in discrete element method(DEM).Unlike traditional approaches that utilize Euler angles or rotation matrices,this model employs unit quaternions to represent the spatial rotations of *** method simplifies the rep-resentation of 3D rotations,providing a more intuitive framework for modelling complex interactions in granular *** numerical model was validated by the uniaxial compression tests on rock,with good agreement with well-documented experimental data in terms of the rock uniaxial compression strength(Ucs)and failure *** loading,the rock sample demonstrated a linear-elastic response at an axial strain of smaller than 0.45%.However,as internal bond breakage accumulated,this linear relationship weakened,and the stress-strain curve began to deviate from its initial linear *** bond breakage and the overall deformation of the rock were primarily controlled by the shear bonding *** Ucs was achieved at an axial strain of 0.625%,at which point the internal shear bonding force chains were predominantly aligned *** brittle failure occurred when the internal damage of solids nucleated to form an interconnected failure plane,accompanied by a sharp rise in the internal damage *** area of failure plane increased with the loading strain rate,gradually transforming the failure pattern from the local damage to a complete fragmentation.

关键词： Brittle failure Quaternion DEM bonded model Uniaxial compression test Rate dependent Internal damage

Quantifying foliar trait variation and covariation in sun and shade leaves using leaf spectroscopy in eastern North America

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Forest Ecosystems 2024年第5期11卷 728-742页

作者： Zhihui Wang philip A.Townsend Eric L.Kruger Anna K.schweiger Guangdong Provincial Key Laboratory of Remote sensing and Geographical Information system Guangdong Open Laboratory of Geospatial Information Technology and ApplicationGuangzhou Institute of GeographyGuangdong Academy of SciencesGuangzhou510070China Department of Forest and Wildlife Ecology University of Wisconsin-Madison1630 Linden DriveMadisonWI53706USA Department of Land Resources and Environmental sciences Montana State University334 Leon Johnson HallBozemanMT59717USA

characterizing foliar trait variation in sun and shade leaves can provide insights into inter-and intra-species resource use strategies and plant response to environmental ***,datasets with records of multiple foliar traits from the same individual and including shade leaves are sparse,which limits our ability to investigate trait-trait,trait-environment relationships and trait coordination in both sun and shade *** presented a comprehensive dataset of 15 foliar traits from sun and shade leaves sampled with leaf spectroscopy,including 424 individuals of 110 plant species from 19 sites across eastern North *** investigated trait variation,covariation,scaling relationships with leaf mass,and the effects of environment,canopy position,and taxonomy on trait ***,sun leaves had higher leaf mass per area,nonstructural carbohydrates and total phenolics,lower mass-based chlorophyll a+b,carotenoids,phosphorus,and potassium,but exhibited species-specific *** between sun and shade leaf traits,and trait-environment relationships were overall consistent across *** main dimensions of foliar trait variation in seed plants were revealed including leaf economics traits,photosynthetic pigments,defense,and structural *** and canopy position collectively explained most of the foliar trait *** study highlights the importance of including intra-individual and intra-specific trait variation to improve our understanding of ecosystem *** findings have implications for efficient field sampling,and trait mapping with remote sensing.

关键词： Foliar traits Leaf trait variation Trait-environment covariation shade leaves NEON Leaf spectroscopy

Investigations of nuclear chirality at iThemba LABs

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Frontiers of physics 2024年第2期19卷 7-38页

作者： R.A.Bark E.A.Lawrie c.Liu s.Y.Wang iThemba Laboratory for Accelerator Based sciences National Research FoundationP.O.Box 722Somerset-West 7129South Africa Department of Physics University of the Western CapePrivate Bag X177535BellvilleSouth Africa shandong Provincial Key Laboratory of Optical Astronomy and solar-Terrestrial Environment Institute of Space SciencesShandong UniversityWeihai 264209China

Progress in the studies of chirality in atomic nuclei at iThemba LABs is *** regions of chirality,around mass 80 and 190 have been discovered using the AFRODITE array,specifically in the nuclei^(74)As,^(78,80,82)Br,^(81)Kr,and^(193,194,198)*** phenomena have been observed,including multiple chiral bands in the same nucleus,the coexistence of octupole correlations and nuclear chirality,and the coexistence of pseudo spin and nuclear *** best example of chiral degeneracy to date was found in ^(194)*** level scheme of ^(106)Ag has been revisited and interpreted in terms of two-and four-quasiparticle *** using the particle-rotor model have shown that the fingerprints of chirality in the two-quasiparticle system only can occur in an idealised model *** systems with a higher number of quasiparticles,the calculations showed that nuclear chirality can persist.

关键词： chirality high-spin states particle-rotor model

Enumerating Pattern-avoiding Fishburn Permutations subject to seven statistics

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Journal of Mathematical Research with Applications 2024年第4期44卷 427-436页

作者： Yujie DU philip B.ZHANG college of Mathematical science Tianjin Normal University

Fishburn permutations are in bijection with several important combinatorial structures including interval orders. In this paper, we use the method of generating trees to enumerate two classes of pattern-avoiding Fishburn permutations subject to 7 classical statistics simultaneously. The classes of our interest are(321,312)-avoiding and(321,4123)-avoiding Fishburn permutations. The statistics of our interest are ascents, descents, inversions, right-to-left maxima, right-to-left minima, left-to-right maxima and left-to-right minima. Our results generalize a result by Egge.

关键词： Fishburn permutation Fishburn number pattern avoidance generating tree

Improving a Patient’s cVD Risk Assessment—Updating the Interpretation of the Lipid Profile

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World Journal of cardiovascular Diseases 2024年第9期14卷 515-520页

作者： David s. schade Allen Adolphe Robert philip Eaton Department of Internal Medicine University of New Mexico Health Sciences Albuquerque USA Department of Internal Medicine School of Medicine University of New Mexico Albuquerque USA

The lipid profile remains an important laboratory assessment to prevent cardiovascular disease. Interpretation of the non-fasting lipid profile has significantly changed based on new information concerning the pathogenesis of atherosclerosis. In particular, the assessment of risk from cholesterol containing particles following triglyceride metabolism (termed remnant cholesterol) can now be done from a lipid profile. In addition, non-HDL cholesterol as calculated from the lipid profile will provide a complete assessment of total circulating cholesterol containing particles. Furthermore, the formula for measurement of LDL cholesterol from a lipid profile has now been revised so that triglyceride levels exert less interference. Finally, the old concept that the “higher the HDL-c, the better” is no longer tenable. New data indicate that the optimal high density lipoprotein level is below 100 mg/dl for both male and female patients. correct interpretation of the lipid profile will optimize anti-atherosclerotic therapy and reduce the number one cause of death in the United states.

关键词： Lipid Profile Atherosclerotic Risk cardiovascular Disease High Density Lipoprotein Low Density Lipoprotein

“差异化最优”和“纵向一体化”理论对中国的意义

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开放时代 2024年第1期 162-173,M0008页

作者：黄宗智中国人民大学法学院历史与社会高等研究所美国加利福尼亚大学洛杉矶校区历史系(荣休)

除了关于小农户作为一个既是生产也是消费的经济单位而形成的诸多特点的理论论析之外,恰亚诺夫的另外两大理论贡献,一是说明小农经济生产遵循的不是简单的规模经济效益,而是“差异化最优”的逻辑,二是提出小农户为了应对大市场,需要扎... 详细信息

除了关于小农户作为一个既是生产也是消费的经济单位而形成的诸多特点的理论论析之外,恰亚诺夫的另外两大理论贡献,一是说明小农经济生产遵循的不是简单的规模经济效益,而是“差异化最优”的逻辑,二是提出小农户为了应对大市场,需要扎根于小农户自身组织的“纵向一体化”的合作社来维护其生产收益。前者可以充分见证于中国近几十年来的“新农业革命”,后者则特别清晰地展示于“东亚地区”(主要指日本、韩国及中国台湾地区)1945年以来非常突出的小农经济现代化经验。近二十年的中央一号文件充分见证了国家农政的重点之前在模仿美国模式和简单的规模经济效益理论,但在2018年以来则转向以小农经济为生产主体和以小农社区为合作社主体的新趋向,既见证也推进和有选择性地改组了上述恰亚诺夫的两大理论洞见。

关键词：小农户 “东亚模式” 小农社区合作社新型物流体系前瞻设想

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