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The radiative decay D^(0)→ K^(*0)γ with vector meson dominance

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Chinese Physics C 2018年第4期42卷 135-141页

作者： J.M.Dias V.R.Debastiani 谢聚军 E.Oset Institute of Modern Physics Chinese Academy of Sciences Departamento de fisica teorica and IFIC Centro Mixto Universidad de Valencia-CSICInstitutos de Investigacion de Paterna Instituto de fisica Universidade de Sao Paulo

Motivated by the experimental measurements of D0 radiative decay modes, we have proposed a model to study the D0→ K＊0γ decay, by establishing a link with D0→ K＊0V （V=ρ0, ω） decays through the vector meson dominance hypothesis. In order to do this properly, we have used the Lagrangians from the local hidden gauge symmetry approach to account for Vγ conversion. As a result, we have found the branching ratio B[D0→ K＊0γ]=（1.55-3.44）×10-4, which is in fair agreement with the experimental values reported by the Belle and BaBar collaborations.

关键词： radiative decay vector meson dominance local hidden gauge symmetry

A Proposal for the Automatic Computation of Envelopes of Families of Plane Curves

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Journal of Systems Science & Complexity 2019年第1期32卷 150-157页

作者： BOTANA Francisco RECIO Tomás depto. de Matemática Aplicada I Universidad de Vigo Campus A Xunqueira depto. de Matemáticas Estad'?stica y Computación Universidad de Cantabria

The idea of envelope of a family of plane curves is an elementary notion in differential geometry. As such, its implementation in dynamic geometry environments is quite universal(Cabri,The Geometer's Sketchpad, Cinderella, Geo Gebra,...). Nevertheless, most of these programs return,when computing certain envelopes, both some spurious solutions and the curves that truly ?t in the intuitive de?nition of envelope. The precise distinction between spurious and genuine parts has not been made before: This paper proposes such distinction in an algorithmic way, ready for its implementation in interactive geometry systems, allowing a ?ner classi?cation of the different parts resulting from the current, advanced approach to envelope computation and, thus, yielding a more precise output, free from extraneous components.

关键词： Automated deduction in geometry dynamic geometry envelopes parametric polynomial systems symbolic computation

A Quantum Field Theory Toy-Model for Magnetic Epigenetic

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Journal of Modern Physics 2013年第8期4卷 1133-1138页

作者： Fabio Burigana Euro Spallucci Claudio Verzegnassi AMEC (Association for Medicine and Complexity) Trieste Italy Dipartimento di fisica Sezione Teorica Università di Trieste and INFN Trieste Italy Dipartimento di fisica Sezione Teorica Università di Trieste and INFN Trieste Udine Italy

We consider the effects that a magnetic field has on the observable properties of an elementary one-fermion state, assumed for simplicity to be that of one electron. We show that for a weak intensity of the field these effects can be very simply computed in a quantum field theory theoretical framework, assuming the minimal form of the electromagnetic interaction and the validity of the Dirac equation. The effects proceed via preliminary, magnetic field induced, modification of the four components of the spinor field. These generate consequent modifications of the various observable properties of the fermion, which can always be simply expressed in terms of the four spinor field components. A few general features of the various effects are discussed, and a number of possible analogies with the fascinating medical description of the epigenetic process for an organic cell are finally proposed.

关键词： Epigenetics Quantum Field Theory Dirac Equation

On the Large-Scale Structure of the Universe as given by the Voronoi Diagrams

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Chinese Journal of Astronomy and Astrophysics 2006年第4期6卷 387-395页

作者： L. Zaninetti Dipartimento di fisica Generale

The size distributions of 2D and 3D Voronoi cells and of cells of Vp（2, 3）,--2D cut of 3D Voronoi diagram--are explored, with the slngle-parameter （re-scaled） gamma distribution playing a central role in the analytical fitting. Observational evidence for a cellular universe is briefly reviewed. A simulated Vp（2, 3） map with galaxies lying on the cell boundaries is constructed to compare, as regards general appearance, with the observed CfA map of galaxies and voids, the parameters of the simulation being so chosen as to reproduce the largest observed void size.

关键词： surveys -- galaxies clusters general -- (cosmology:) large-scale structure of Universe

Primary crystallization process of rapidly solidified Al-Ni-Cu-Nd metallic glasses under continuous heating regime

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中国有色金属学会会刊：英文版 2003年第4期13卷 764-768页

作者：肖于德黎文献 D.Jacovkis N.Clavaguera M.T.Clavaguera-Mora J.Rodriguez-Viejo School of Materials science and Engineering Grup de fisica de Materials I fisica de l'Estat Solid

Rapidly solidified Al 87 Ni 7Cu 3Nd 3 metallic glasses were prepared by using melt spinning. Its calorimetric behavior was characterized by using differential scanning calorimeter. The metallic glasses were partially crystallized under continuous heating regime. Primary crystallization was studied through structural characterization of the amorphous and partially crystallized ribbons by means of conventional X ray diffraction and transmission electron microscopy with selected area electron diffraction. The results show that, the as spun ribbons are fully amorphous and homogeneous on the micron scale, but contain high density of nanoscale quenched in clusters or crystallite embryos. Primary crystallization mainly leads to formation of two phase mixture of α Al nanocrystalline and residual amorphous phase. Precipitation of α Al nanoparticles is limited by build up and overlapped diffusion field of solute atoms with low diffusion rate. At the earlier stage of primary crystallization the crystal nuclei exhibit high density and growth rate. With the α Al crystal growing, the crystal growth rate decreases, and even at the later stage further crystallization into α Al crystal becomes difficult to occur due to thermal stabilization of the residual nickel and neodymium enriched amorphous phase, the saturated values of crystallized volume fraction and α Al crystal diameter getting to 20%30% and 515 nm.

关键词：铝合金快速凝固连续加热制度结晶过程金属玻璃

Light Front Boson Model Propagation

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Communications in Theoretical Physics 2011年第6期55卷 1029-1040页

作者： Jorge Henrique Sales Alfredo Takashi Suzuki Universidade Estadual de Santa Cruz km 16 Rodovia Ilheus-Itabuna-45662-900-IlheusBABrazil Instituto de fisica teorica UNESP-Universidade Estadual PaulistaRua Dr.Bento Teobaldo Ferraz 271-Bl.ⅡBarra Funda01140-070Sao PauloSao PauloBrazil

这的范围和工作是描述二身体的相互作用的目的在轻前面的明确的表达以内由一个粒子(数量或计量器波色子) 调停了。做这，首先，我们在量力学指出增殖者和格林功能的重要性。然后，我们投射 covariant 量增殖者到轻前面时间上在这些坐标... 详细信息

这的范围和工作是描述二身体的相互作用的目的在轻前面的明确的表达以内由一个粒子(数量或计量器波色子) 调停了。做这，首先，我们在量力学指出增殖者和格林功能的重要性。然后，我们投射 covariant 量增殖者到轻前面时间上在这些坐标为分级的粒子得到增殖者。这个操作符从 x+= 宣传波浪函数 0 到 x+> 0。它对应于在轻前面时间 x+ 订操作的时间的定义。我们为在 x+ 向前宣传的 2 交往波色子计算轻前面的格林的功能。我们也显示出怎么从 Feynman 增殖者写下轻前面格林的功能并且最后做归纳到 N 波色子。

关键词：玻色子模型传播者格林函数标量粒子时间顺序相互作用量子力学规范玻色子

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BKP方程族的Pfaffian解

数学年刊（A辑） 2002年第6期23卷 693-698页

作者：刘青平 M.MANAS 中国矿业大学 Departamento de fisica teorica Ⅱ Universidad Complutense

本文从约化的角度考虑BKP方程族的Pfaffian形式的解.证明了通过施加适当的微分约束,KP方程族的格拉姆行列式的解很自然的约化为BKP方程族的解.

关键词：孤立子达布变换 KP方程族 BKP方程族 Pfaffian解

Combined Environmental and Magnetic Effects on Elementary Matter: A Quantum Field Theory Description of Fermion Epigenetics

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Journal of Modern Physics 2014年第3期5卷 99-102页

作者： Euro Spallucci Claudio Verzegnassi Dipartimento di fisica Sezione Teorica Università di Trieste and INFN Sezione di Trieste Italy

We compute in a theoretical quantum field theory framework the effects that a classic environment will have on an elementary one-fermion state, assumed for simplicity to be that of one electron, in the presence of a magnetic field. We consider its total energy and its spin angular momentum as relevant observables of the state. We show that the changes of these quantities produced by the combined environmental and magnetic effects can be expressed in a simple and compact form. We obtain expressions that only depend on the values of the external environment and magnetic fields, and on the special spin features of the free fermion state. We call these effects “fermion epigenetics” and try to motivate this definition discussing possible relevant analogies with the corresponding medical treatment of epigenetics in organic cells.

关键词： Epigenetics Quantum Field Theory Dirac Equation

Dielectric spectroscopy characterization of Naþ ion-conducting polymer nanocomposite system PEO–PVP–NaIO_(4)–TiO_(2)

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Journal of Advanced Dielectrics 2024年第1期14卷 59-73页

作者： Georgi B.Hadjichristov Daniela G.Kovacheva Yordan G.Marinov Daniela B.Karashanova Todor E.Vlakhov Nicola Scaramuzza Georgi Nadjakov Institute of Solid State Physics Bulgarian Academy of Sciences 72 Tzarigradsko Chaussee Blvd.BG-1784 SofiaBulgaria Institute of General and Inorganic Chemistry Bulgarian Academy of Sciences Acad.Georgi Bonchev Str. 11 bd.BG-1113 SofiaBulgaria Institute of Optical Materials and Technologies“Acad.Jordan Malinowski” Bulgarian Academy of Sciences Acad.Georgi Bonchev Str.bl.109BG-1113 SofiaBulgaria Dipartimento di fisica Universita degli Studi della Calabria Via P.BucciCubo 33BRende(CS)IT-87036Italy

We studied the effect of titanium dioxide(TiO_(2))nanoparticles(NPs)on dielectric behavior of Naþion-conducting salt-complexed polymer nanocomposite system formed from a binary polymer blend of poly(ethylene oxide)(PEO)and polyvinyl pyrrolidone(PVP),with the addition of both sodium metaperiodate(NaIO_(4))at concentration 10 wt.%and TiO_(2) NPs of size10 nm,at concentrations 1,2,3,4 and 5 wt.%.Free standing nanocomposite PEO/PVP/NaIO_(4)/TiO_(2) films(150m)were characterized at room-temperature by analyzing their complex electrical impedance and dielectric spectra in the range 1 Hz–1 *** the concentration of 3 wt.%of TiO_(2) NPs,both ion conductivity and dielectric permittivity of the PEO/PVP/NaIO_(4)/TiO_(2) ion-conducting dielectrics reach an enhancement by more than one order of magnitude as compared to nanoadditive-free case.

关键词： Dielectric properties sodium-ion-polymer electrolyte systems titanium dioxide(TiO_(2))nanoparticles nanocomposites KWW model