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1.
Clear windows onto emergent hadron mass(EHM)and modulations thereof by Higgs boson interactions are provided by observable measures of pion and kaon structure,many of which are accessible via generalised parton distributions(GPDs).Beginning with algebraic GPD Ans?tze,constrained entirely by hadron-scaleπand K valence-parton distribution functions(DFs),in whose forms both EHM and Higgs boson influences are manifest,numerous illustrations are provided.They include the properties of electromagnetic form factors,impact parameter space GPDs,gravitational form factors and associated pressure profiles,and the character and consequences of allorders evolution.The analyses predict that mass-squared gravitational form factors are stiffer than electromagnetic form factors;reveal that K pressure profiles are tighter than profiles,with both mesons sustaining near-core pressures at magnitudes similar to that expected at the core of neutron stars;deliver parameter-free predictions for and K valence,glue,and sea GPDs at the resolving scale l=2GeV;and predict that at this scale the fraction of meson mass-squared carried by glue and sea combined matches that lodged with the valence degrees-of-freedom,with a similar statement holding for mass-squared radii. 相似文献
2.
The subsolidus phase relations of a ZnO-V 2 O 5-K 2 O system are investigated by X-ray powder diffraction.There is 1 ternary compound,11 binary compounds and 14 three-phase regions in this system.The phase diagrams of V 2 O 5 K 2 O with the K 2 O content ranging from 0 to 71 mol% and pseudo-binary system of ZnO-K 2 ZnV 2 O 7 are also studied by X-ray powder diffraction and differential thermal analysis methods. 相似文献
3.
Lax pair and vector semi-rational nonautonomous rogue waves for a coupled time-dependent coefficient fourth-order nonlinear Schrodinger system in an inhomogeneous optical fiber
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Optical fibers are seen in the optical sensing and optical fiber communication. Simultaneous propagation of optical pulses in an inhomogeneous optical fiber is described by a coupled time-dependent coefficient fourth-order nonlinear Schr?dinger system, which is discussed in this paper. For such a system, we work out the Lax pair, Darboux transformation, and corresponding vector semi-rational nonautonomous rogue wave solutions. When the group velocity dispersion(GVD) and fourth-order dispersion(FOD) coefficients are the constants, we exhibit the first-and second-order vector semirational rogue waves which are composed of the four-petalled rogue waves and eye-shaped breathers. Both the width of the rogue wave along the time axis and temporal separation between the adjacent peaks of the breather decrease with the GVD coefficient or FOD coefficient. With the GVD and FOD coefficients as the linear, cosine, and exponential functions, we respectively present the first-and second-order periodic vector semi-rational rogue waves, first-and second-order asymmetry vector semi-rational rogue waves, and interactions between the eye-shaped breathers and the composite rogue waves. 相似文献
4.
Gravitational collapse with standard and dark energy in the teleparallel equivalent of general relativity
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Gamal G.L.Nashed 《中国物理 B》2012,21(6):60401-060401
A perfect fluid with self-similarity of the second kind is studied within the framework of the teleparallel equivalent of general relativity(TEGR).A spacetime which is not asymptotically flat is derived.The energy conditions of this spacetime are studied.It is shown that after some time the strong energy condition is not enough to satisfy showing a transition from standard matter to dark energy.The singularities of this solution are discussed. 相似文献
5.
Breakdown voltage model and structure realization of a thin silicon layer with linear variable doping on a silicon on insulator high voltage device with multiple step field plates
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Based on the theoretical and experimental investigation of a thin silicon layer(TSL) with linear variable doping(LVD) and further research on the TSL LVD with a multiple step field plate(MSFP),a breakdown voltage(BV) model is proposed and experimentally verified in this paper.With the two-dimensional Poisson equation of the silicon on insulator(SOI) device,the lateral electric field in drift region of the thin silicon layer is assumed to be constant.For the SOI device with LVD in the thin silicon layer,the dependence of the BV on impurity concentration under the drain is investigated by an enhanced dielectric layer field(ENDIF),from which the reduced surface field(RESURF) condition is deduced.The drain in the centre of the device has a good self-isolation effect,but the problem of the high voltage interconnection(HVI) line will become serious.The two step field plates including the source field plate and gate field plate can be adopted to shield the HVI adverse effect on the device.Based on this model,the TSL LVD SOI n-channel lateral double-diffused MOSFET(nLDMOS) with MSFP is realized.The experimental breakdown voltage(BV) and specific on-resistance(R on,sp) of the TSL LVD SOI device are 694 V and 21.3 ·mm 2 with a drift region length of 60 μm,buried oxide layer of 3 μm,and silicon layer of 0.15 μm,respectively. 相似文献
6.
Phase properties of the even and odd circular states are
studied within the Hermitian phase formalism of Pegg and Barnett.
Exact analytical formulas for the distribution function and the
variance of the phase operator are obtained and used to examine
whether or not the even and odd circular states exhibit
photon-number squeezing and phase squeezing. 相似文献
7.
A new complex variable element-free Galerkin method for two-dimensional potential problems
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In this paper, based on the element-free Galerkin (EFG) method and the improved complex variable moving least- square (ICVMLS) approximation, a new meshless method, which is the improved complex variable element-free Galerkin (ICVEFG) method for two-dimensional potential problems, is presented. In the method, the integral weak form of control equations is employed, and the Lagrange multiplier is used to apply the essential boundary conditions. Then the corresponding formulas of the ICVEFG method for two-dimensional potential problems are obtained. Compared with the complex variable moving least-square (CVMLS) approximation proposed by Cheng, the functional in the ICVMLS approximation has an explicit physical meaning. Furthermore, the ICVEFG method has greater computational precision and efficiency. Three numerical examples are given to show the validity of the proposed method. 相似文献
8.
Odilon Lourenço César H.Lenzi Mariana Dutra Tobias Frederico M.Bhuyan Rodrigo Negreiros César V.Flores Guilherme Grams Débora P.Menezes 《中国物理C(英文版)》2021,(2):531-547
In the present work,we used five different versions of the quark-meson coupling(QMC)model to compute astrophysical quantities related to the GW170817 event and the neutron star cooling process.Two of the models are based on the original bag potential structure and three versions consider a harmonic oscillator potential to confine quarks.The bag-like models also incorporate the pasta phase used to describe the inner crust of neutron stars.With a simple method studied in the present work,we show that the pasta phase does not play a significant role.Moreover,the QMC model that satisfies the GW170817 constraints with the lowest slope of the symmetry energy exhibits a cooling profile compatible with observational data. 相似文献
9.
The quantum private query(QPQ)is a quantum solution for the symmetrically private information retrieval problem.We study the security of quantum-key-distribution-based QPQ with weak coherent pulses.The result shows that multiphoton pulses have posed a serious threat to the participant’s privacy in QPQ protocols.Then we propose a decoy-state method that can help the honest participant detect the attack by exploiting multiphoton pulses and improving the key distillation process to defend against such attack.The analysis demonstrates that our decoy-state method significantly improves the security of the QPQ with weak coherent pulses,which solves a major obstacle in the practical application of the QPQ. 相似文献
10.
The spin structure of nucleons is presented in the framework of an extended quark model which in addition to the conventional qqq structure also takes into account qqqq admixtures in the nucleon wave functions, where the qqqq components are in colored quark cluster configurations. The axial vector weak coupling constant and spin distributions for polarized nucleons as well as spin content are obtained for the lowest positive parity qqqq configurations in flavor-spin dependent interaction. In particular, the contributions of the down and strange quarks to the proton spin and the sum rule for polarized neutron are negative, in agreement with recent experiments. 相似文献
11.
We find that a kind of atomic coherent state, formed as exp [ξ J+- ξ*J-] |00>, when the SU(2) generators J± are taken as Fan's form, J+=(1/2)(a1-a28224;)(a18224;-a2), J_=(1/2) (a18224;+a2)(a1+a28224;), and J0=(1/2) (a18224;a28224;-a1a2), is simultaneously a two-mode squeezed state. We analyse this squeezed state's physical properites, such as the cross-correlation function, the Wigner function, and its marginal distribution as well as the Husimi function. 相似文献
12.
由于DNA与[Ru(bpy)3]2+(bpy=2,2′-联吡啶)及Cu2+间的静电作用,用自铸膜法在铟锡氧化物(ITO)上制备了橙红色[Ru(bpy)3]2+-DNA-Cu2+复合膜,并应用稳态和暂态荧光光谱、紫外可见光谱、荧光显微镜和扫描电镜对复合膜进行了表征和DNA介导的光诱导电子转移(PET)研究。结果表明,[Ru(bpy)3]2+-DNA-Cu2+复合膜(摩尔比为10∶20∶1)呈现了明显的吸收特征峰(450 nm)和发射峰(λem=595 nm),发光呈单指数衰减,发光寿命为188.6 ns,Cu2+通过DNA介导PET机制猝灭[Ru(bpy)3]2+发光,猝灭常数为6.94×103 L·mol-1,猝灭速率常数为3.80×1010 L·mol-1·s-1;复合膜中Cu2+摩尔比(10倍)的增大使发射峰蓝移了11 nm,吸收和发射强度衰减至消失,Cu2+通过静态猝灭机制削弱[Ru(bpy)3]2+发光。此外,对比于溶液和复合膜中Cu2+对[Ru(bpy)2(tatp)]2+-DNA(tatp=1,4,8,9-四氮三苯)的发光调控,Cu2+仅能因静电作用猝灭复合膜中[Ru(bpy)3]2+的发光。 相似文献
13.
Using the bosonic coherent state representation and the Schwinger bosonic operator realization of angular momentum we find the formula for the quantum Hamiltonian H =iaiUijUjl a1 for SU(2) rotation U, in this way we further specify the angular velocity w, iUU = (1/2)σ·ω, where σ is the Pauli matrix. Though the spin as a quantum observable has no classical correspondence, we may still mimic it as a rigid body rotation characterized by 3 Euler angles, and calculate its Pseudo-classical rotational partition function of spin one-half. 相似文献
14.
We lind that the Fokker-Planck equation in complex variables can be conveniently solved in the context of bipartite entangled state representation and its relationship with SU(2) Lie algebraic generators' new realization {(1/4)[(Q1 - Q2)^2 + (P1+ P2)^2], (1/4)[(Q1 +Q2)^2+ (P1 - P2)^2], and -(i/2)(Q1P2 + Q2P1)}, the quadratic combination of canonical operators. 相似文献
15.
采用密度泛函理论对以偶氮二异丁腈为引发剂形成的丙烯腈单体自由基(CH3)2(CN)C—CH2—(CN)CH的终止方式反应机理进行研究。先用B3LYP/6-31G(d)基组对反应物、偶合中间体、过渡态、歧化产物的几何构型进行优化,并计算了各物种经过零点能校正后的总能量,红外频率和电子结构,同时对过渡态结构进行了验证。研究结果表明,反应物先通过自由基的偶合终止方式形成偶合中间体a,再由此经过氢迁移、裂解等机理得到歧化终止产物P[p1(CH3)2(CN)CCHCHCN+p2(CH3)2(CN)C—CH2—CH2CN]。双自由基发生偶合和歧化终止反应分别形成偶合中间体a和歧化终止产物P均为放热反应,且偶合产物有着更低的能量。反应过程的速控步骤a→TS→P在常温下的速率常数表示为k(298.15 K)=2.71×10-59。歧化终止反应随着反应温度的升高易于进行,歧化产物所占的比例也增加。通过对反应过程各物种红外谱图的分析,说明自由基在整个终止反应的化学变化,同时分析了HOMO-LUMO电子密度分布的信息,验证丙烯腈双自由基偶合终止方式和各物种结构的准确性。 相似文献
16.
利用金刚石对顶砧在常压至12.85 GPa条件下对β-胡萝卜素进行了原位高压拉曼光谱测量,讨论了β-胡萝卜素分子特征峰频率随压力的变化规律及其π-电子离域受压力的影响。实验结果表明,β-胡萝卜素的各特征峰均向高波数移动,其主要的三个特征峰的拉曼频率与压力的关系为:ν1(CC)=4.74P+1 511.4, ν2(C—C)=2.55P+1 157.6和ν3(CH3)=2.25P+1 011.3,β-胡萝卜素的ν1+ν2和频峰在5.38 GPa的压力条件下发生劈裂。对实验结果进一步分析发现随压力增大β-胡萝卜素分子的β环扭转变化使其π-电子离域程度变弱, 导致β-胡萝卜素分子主链上的碳碳双键比碳碳单键更容易压缩。 相似文献
17.
We investigate statistical properties of multispecies competition ecosystems subjected to both symmetric and asymmetric dichotomous noises. The expression of the stationary probability distribution function (SPDF) is analytically derived by means of mean-field approximation, and verified bystochastic simulations. The results indicate that: (i) A noiseamplitude (a0), a noise autocorrelation time (τ0) and a noise symmetry parameter (k) all can affect the SPDF; (ii) There is an optimal τ0, which makes the mean value of population density be maximal, near which a transition takes place, i.e., the stationary mean value of species density (st) suddenly falls to a lower constant; (iii) As k decreases, the maximum of< x>st and the optimal τ0 increase. The parameter planes of τ0-a02 and τ0-k for the transition are plotted. 相似文献
18.
LI Xiao-Wei 《理论物理通讯》2010,54(6):1139-1143
Using the extended Blonder-Tinkham-Klapwijk formalism, we investigate the conductance spectra of normal metal/dx2-y2+idxy mixed wave superconductor graphene junctions. It is found that the conductance spectra vary strongly with the orientation of the gap and the amplitude ratio (Δ1/Δ0) of two components for dx2-y2+idxy mixed wave. The zero bias conductance isnearly 2 and the conductance peak vanishes in doped graphene forα=0 and Δ1/Δ0=1. The conductance increases with increasing the amplitude ratio of two components for α=π/4 and Δ1/Δ0=1. The ZBCP becomesobservable wide with 1F/Δ0<100 for α=π/4 and Δ1/Δ0=1. This property is different from that in normal metal/dx2-y2 wave superconductor graphenejunctions. 相似文献
19.
3,4-噻吩二羧酸(3,4-H2tdc),1,10-邻菲罗啉(phen)和稀土硝酸盐经水热法合成三种配合物Ln2(Htdc)2(tdc)2(phen)2(H2O)4(Ln=Eu 1, Gd 2, Tb 3),并用X-射线单晶衍射分析方法测定了配合物1-3晶体结构,配合物1-3为双核分子。每个金属离子周围有2个3,4-tdc,1个3,4-Htdc,1个phen和2个配位水分子,配位数为9。配合物1和3在紫外灯下显强红光和绿光,其荧光发射光谱,在619和545 nm出现最大发射峰,分别对应于Eu(Ⅲ)离子的5D0→7F2和Tb(Ⅲ)离子的5D4→7F5跃迁。配合物2在425 nm观察到来自基于配体的π*→π最大发射峰。不同溶剂分子对配合物1荧光有不同程度的影响,基于荧光猝灭机理,配合物1具有选择性检测硝基苯污染物的能力。 相似文献
20.
常温高压下碳酸根离子的拉曼谱峰标定压力初探 总被引:2,自引:1,他引:1
在准静水压的条件下,利用碳化硅压腔和显微拉曼光谱原位测量技术,在0~1.7 GPa压力范围测定22 ℃高压下三种不同的H2O-Na2CO3体系(1.5,2.0,2.5 mol·L-1)中CO2-3的对称伸缩振动ν1 066拉曼谱峰的变化。结果表明,在室温条件下,碳酸根的ν1 066峰的拉曼位移随着压力的增大而线性增加。三种浓度下ν1 066峰的拉曼位移与压力的拟合直线彼此接近,斜率误差小于1%,偏差小于系统误差,因此在实验误差范围内碳酸根浓度对ν1 066峰随压力变化的行为不存在影响。经过数据拟合得到公式:p/MPa=174.13 Δν1 066/cm-1—59.03(Δν1 066=ν1 066-ν1 0660,ν1 0660为体系零压时碳酸根离子ν1 066峰的拉曼位移)。此公式可以用于常温下在含有纯碳酸钠体系中的压力标定。 相似文献