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Formation region of emitted α and heavier particles inside radioactive nuclei

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Chinese Physics C 2020年第7期44卷 118-125页

作者： w.M.Seif A.M.h.Abdelhady Cairo University Faculty of ScienceDepartment of Physics12613 GizaEgypt Beni-Suef University Faculty of Navigation Science and Space Technology62514 Beni-SuefEgypt

we investigate the formation distance(R0)from the center of the radioactive parent nucleus at which the emitted cluster is most probably *** calculations are performed microscopically starting with the solution to the time-independent Schr?dinger wave equation for the cluster-core system,using nuclear potentials based on the Skyrme-SLy4 nucleon-nucleon interactions and folding Coulomb potential,to determine the incident and transmitted wave functions of the *** results show that the emitted cluster is mostly formed in the pre-surface region of the nucleus,under the effect of Pauli blocking from the saturated core *** deeperα-formation distance inside the nucleus allows less preformation probability and indicates a more stable nucleus for a longer ***,theα-particle tends to be formed at a slightly deeper region inside the nuclei,with larger isospin asymmetry,and in the closed shell *** the heavy clusters,we observed that the formation distance of the emitted clusters heavier thanα-particle increased via increasing the isospin asymmetry of the formed cluster rather than by increasing its mass *** partial half-life of a certain cluster-decay mode increased with increase of either the mass number or the isospin asymmetry of the emitted cluster.

关键词： alpha-decay cluster decay Skyrme-SLy4 nucleon-nucleon interaction formation region

Rheological Regime of the Upper Mantle beneath the Taiwan Strait and Its Tectonic Significance

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Acta Geologica Sinica(English Edition) 1995年第3期69卷 259-271,340页

作者： h.w.GreenⅡ U яivetsity of California RiuersideC A 92521U.S.A.

This paper deals with deformation textures and fabrics of mantle-derived xenoliths and dislocation microstructures of olivine in the upper mantle in the Penghu Islands, Taiwan. According to the calculation of the chemical composition of xenolith minerals (pyroxene), the equilibrium temperatures and pressures were 986-1116@ and 1.50-2.60 GPa, respectively. Deformation events in the upper mantle may fall into three sequences' (1) uniform steady-state flow deformation with high temperatures and low stresses, (2) shear flow deformation with high temperatures and relatively high stresses on diapiric margins of the upper mantle, and (3) extraction deformation of {110} glide bands with low temperatures and high strain rates. Deformation events and thermal structure of the upper mantle in the study area show that eastern Fujian and the Penghu Islands are characterized by very similar rheological properties of the upper mantle. Volcanism of basalts in the Penghu Islands is related to hot spots of the upper mantle under neath the Taiwan Strait, and diapirism and upwelling of the upper mantle are the dominant factors responsible for rifting of the continental margins in eastern China.

关键词： mantle-derived xenolith high-temperature creep rheology of the upper mantle rifting Penghu Islands

Effect of Fly Ash on Rheological Properties of Cement Paste

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武汉理工大学学报 2010年第17期32卷 186-192页

作者： ChEN w hUANG h School of Materials Science and Engineering Wuhan University of TechnologyWuhan 430070China

This paper is aimed to study the factors influencing rheological properties of cement paste with fly ash,including the quantity of cement replaced by fly ash,types of the fly ash,degree of cement hydration and the microstructure of cement paste. By changing the water-cement ratio,mixing different amounts of fly ash,adding different types fly ash,the rheological parameters of cement paste are measured with a rheometer,and the needle penetration are tested by Vical needle. A ultrasound velocity test was aslo employed to monitor hydration of paste at early ages. Combinations of different factors on the rheological properties of cement paste are studied. The objective is to reveal the effect mechanism of material nature and proportion of each component on the rheological properties of cement paste with fly ash.

关键词： rheology cement paste fly ash needle penetration ultrasound velocity

Free vibration and transient response of double curved beams connected by intermediate straight beams

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Applied Mathematics and Mechanics(English Edition) 2025年第1期46卷 37-62页

作者： R.A.JAFARI-TALOOKOLAEI h.GhANDVAR E.JUMAEV S.KhATIR T.CUONG-LE School of Mechanical Engineering Babol Noshirvani University of Technology Department of Mechanical Engineering Faculty of Engineering New Uzbekistan University University of Business and Science Center for Engineering Application and Technology Solutions Ho Chi Minh City Open University

This paper investigates the free vibration and transient response of interconnected structures including double curved beams and intermediate straight beams,which are all constructed from functionally graded porous(FGP) materials. The strain potential and kinetic energies of each beam along with the work done by the external force are calculated. Additionally, a higher-order beam element is introduced to derive stiffness and mass matrices, along with the force vector. The curved and straight beams are discretized, and their assembled stiffness, mass matrices, and force vectors, are *** conditions at the joints are used to derive the total matrices of the entire structure. Subsequently, the natural frequencies and transient response of the system are determined. The accuracy of the mathematical model and the self-developed computer program is validated through the comparison of the obtained results with those of the existing literature and commercial software ANSYS, demonstrating excellent ***, a comprehensive study is conducted to investigate the effects of various parameters on the free vibration and transient response of the considered structure.

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Stepwise assembly to construct stable copper(I) cluster-based circularly polarized luminescent MOFs

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Science China Chemistry 2025年

作者： Jing-wen Xie Meng-Ting wang Yan Jin Si Li Jian-hua Qin Shuang-Quan Zang Tomas C.w.Mak College of Chemistry Henan Key Laboratory of Crystalline Molecular Functional Materials Zhengzhou University College of Chemistry and Chemical Engineering Luoyang Normal University Department of Chemistry The Chinese University of Hong Kong

Circularly polarized luminescence （CPL） materials have been extensively studied in recent years owing to their widespread applications in 3D display,optical storage,optical anti-counterfeiting,and biological imaging,***（I） clusters have emerged as a promising candidate for CPL materials,driven by their cost-effectiveness,superior luminescent properties,precise structure,and low ***,the poor environmental stability of copper（I） clusters renders their synthesis and preservation challenging,thereby significantly impeding their ***,we have designed and synthesised a chiral double-coordinated ligand in order to construct copper（I） cluster nodes that can be further *** anticipated,by utilizing stepwise assembly strategy,a Cu4cluster node co-modified by chiral alkynyl ligands and triphenylphosphine was further assembled with Cd2+ions to obtain 2D layers structure,L/*** L/D-Cu4-Cd exhibits excellent stability and optical properties,including bright yellow emission,solvent-responsive luminescence,and CPL activity with a maximum glumup to 2.0×10-3,which shows potential applications in the wLED and *** interestingly,the material also exhibits deflection ability towards different wavelengths of linearly polarized light,showing certain potential in the preparation of circular polarizer.

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A micromechanical model based on hypersingular integro-differential equations for analyzing micro-crazed interfaces between dissimilar elastic materials

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Applied Mathematics and Mechanics(English Edition) 2020年第2期41卷 193-206页

作者： X.wANG w.T.ANG h.FAN School of Mechanical and Aerospace Engineering Nanyang Technological University50 Nanyang AvenueSingapore 639798Singapore

The current work models a weak(soft) interface between two elastic materials as containing a periodic array of micro-crazes. The boundary conditions on the interfacial micro-crazes are formulated in terms of a system of hypersingular integro-differential equations with unknown functions given by the displacement jumps across opposite faces of the micro-crazes. Once the displacement jumps are obtained by approximately solving the integro-differential equations, the effective stiffness of the micro-crazed interface can be readily computed. The effective stiffness is an important quantity needed for expressing the interfacial conditions in the spring-like macro-model of soft interfaces. Specific case studies are conducted to gain physical insights into how the effective stiffness of the interface may be influenced by the details of the interfacial micro-crazes.

关键词： micromechanical modeling micro-crazed interface effective stiffness coefficient hypersingular integro-differential equation

A fast-running method for blast load prediction shielding by a protective barrier

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Defence Technology（防务技术） 2020年第2期16卷 308-315页

作者： S.-h.Sung J.-w.Chong Agency for Defense Development Yuseong P.O.Box 35DaeJeon395-600South Korea

This study presents a simplified blast load prediction method on structures behind a protective *** proposed method is basically an empirical approach based on Kingery-Bulamsh(K-B)chart and finite element(FE)analysis *** this end,this study divides the structure into three regions by three critical *** loads at each critical point can be calculated based on K-B chart and an approximation according to FE analysis ***,peak reflected overpressure and impulse distributed on the structure can be approximately estimated by linearly connecting blast loads at each critical *** order to confirm a feasibility of the proposed method,a series of numerical simulations were carried *** simulation results were compared with FE analysis results which are presented in the open *** such comparisons,it was found that the proposed method is applicable to predict blast loads on structures behind a protective barrier.

关键词： Blast loads Protective barrier Shock wave Fast running model Kingery-Bulmash

Impact of intraocular pressure fluctuations on progression of normal tension glaucoma

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International Journal of Ophthalmology(English edition) 2021年第10期14卷 1553-1559页

作者： Susanne hopf Doris Schwantuschke Irene Schmidtmann Norbert pfeiffer Esther Maria hoffmann Department of Ophthalmology University Medical Center MainzMainz 55131Germany Pediatric Dentistry Nieder-Olm 55268Germany Institute of Medical Biostatistics Epidemiology and Informatics(IMBEI)University Medical Center MainzMainz 55131Germany

AIM:To investigate short-and long-term intraocular pressure(IOP)fluctuations and fur ther ocular and demographic parameters as predictors for normal tension glaucoma(NTG)***:This retrospective,longitudinal cohort study included 137 eyes of 75 patients with NTG,defined by glaucomatous optic disc or visual field defect with normal IOP(hg),independently from therapy *** fluctuation,mean,and maximum were inspected with a mean follow-up of 38 mo[standard deviation(SD)18 mo].Inclusion criteria were the performance of minimum two 48-hour profiles including perimetry,heidelberg retina tomograph(hRT)imaging,and optic disc *** impact of IOP parameters,myopia,sex,cup-to-disc-ratio,and visual field results on progression of NTG were analyzed using Cox regression models.A sub-group analysis with results from optical coherence tomography(OCT)was ***:IOP fluctuations,average,and maximum were not risk factors for progression in NTG patients,although maximum IOP at the initial IOP profile was higher in eyes with progression than in eyes without progression(P=0.054).The 46/137(33.5%)eyes progressed over the followup *** progression(at least three progression confirmations)occurred in 28/137 eyes(20.4%).Most progressions were detected by perimetry(36/46).Longterm IOP mean over all pressure profiles was 12.8 mm hg(SD 1.3 mm hg);IOP fluctuation was 1.4 mm hg(SD 0.8 mm hg).The progression-free five-year rate was 58.2%(SD 6.5%).CONCLUSION:Short-and long-term IOP fluctuations do not result in progression of *** functional changes are most likely to happen,NTG should be monitored with visual field testing more often than with other devices.

关键词： intraocular pressure intraocular pressure fluctuation glaucoma progression visual field optical optical coherence tomography

The AME2012 atomic mass evaluation(Ⅰ).Evaluation of input data,adjustment procedures

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Chinese Physics C 2012年第12期36卷 1603-2014页

作者： G.Audi M.wang A.h.wapstra F.G.Kondev M.MacCormick X.Xu B.pfeiffer Centre de Spectrométrie Nucleate et de Spectrométrie de Masse CSNSMCNRS/IN2P3Université Paris-SudBt.108F-91405 Orsay CampusFrance Institute of Modem Physics CAS509 Nanchang Rd.Lanzhou 730000China Max-Planck-Institut fr Kernphysik Saupfercheckweg 1D-69117 HeidelbergGermany National Institute of Nuclear Physics and high-Energy Physics NIKHEF1009DB AmsterdamThe Netherlands Argonne National Laboratory 9700 S.Cass AvenueArgonneIL 60439USA Institut de Physique Nucléaire CNRS/IN2P3Universite Paris-SudF-91406 Orsay cedexFrance Graduate University of Chinese Academy of Sciences Beijing100049People's Republic of China GSI helmholtzzentram fr Schwerionenforschimg Planckstr.1D-64291 DarmstadtGermany

This paper is the second part of the new evaluation of atomic masses, AME2012. From the results of a leastsquares calculation, described in Part I, for all accepted experimental data, we derive here tables and graphs to replace those of AME2003. The first table lists atomic masses. It is followed by a table of the influences of data on primary nuclides, a table of separation energies and reaction energies, and finally, a series of graphs of separation and decay energies. The last section in this paper lists all references to the input data used in Part I of this AME2012 and also to the data included in the NUBASE2012 evaluation （first paper in this issue）.

关键词： AME The AME2012 atomic mass evaluation Evaluation of input data,adjustment procedures data