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991.
In this paper,the(2+1)-dimensional Hunter-Saxton equation is proposed and studied.It is shown that the(2+1)-dimensional Hunter–Saxton equation can be transformed to the Calogero–Bogoyavlenskii–Schiff equation by reciprocal transformations.Based on the Lax-pair of the Calogero–Bogoyavlenskii–Schiff equation,a non-isospectral Lax-pair of the(2+1)-dimensional Hunter–Saxton equation is derived.In addition,exact singular solutions with a finite number of corners are obtained.Furthermore,the(2+1)-dimensional μ-Hunter–Saxton equation is presented,and its exact peaked traveling wave solutions are derived. 相似文献
992.
Recently, a novel idea [1] has been proposed to relax the electroweak hierarchy problem through the cosmological inflation and the axion periotic potential. Here, we further assume that only the attractive inflation is needed to explain the light mass of the Higgs boson, where we do not need a specified periodic potential of the axion field. Attractive inflation during the early universe drives the Higgs boson mass from the large value in the early universe to the small value at present, where the Higgs mass is an evolving parameter of the Universe. Thus, the small Higgs mass can technically originate from the cosmological evolution rather than dynamical symmetry or anthropics. Further, we study the possible collider signals or constraints at a future lepton collier and the possible constraints from the muon anomalous magnetic moment. A concrete attractive relaxion model is also discussed, which is consistent with the data of Planck 2015. 相似文献
993.
Stability Analysis of a Fully Coupled Implicit Scheme for Inviscid Chemical Non-Equilibrium Flows 下载免费PDF全文
Von Neumann stability theory is applied to analyze the stability of a fully
coupled implicit (FCI) scheme based on the lower-upper symmetric Gauss-Seidel (LU-SGS)
method for inviscid chemical non-equilibrium flows. The FCI scheme shows excellent
stability except the case of the flows involving strong recombination reactions,
and can weaken or even eliminate the instability resulting from the stiffness problem,
which occurs in the subsonic high-temperature region of the hypersonic flow field. In
addition, when the full Jacobian of chemical source term is diagonalized, the stability
of the FCI scheme relies heavily on the flow conditions. Especially in the case of high
temperature and subsonic state, the CFL number satisfying the stability is very small.
Moreover, we also consider the effect of the space step, and demonstrate that the stability
of the FCI scheme with the diagonalized Jacobian can be improved by reducing
the space step. Therefore, we propose an improved method on the grid distribution
according to the flow conditions. Numerical tests validate sufficiently the foregoing
analyses. Based on the improved grid, the CFL number can be quickly ramped up to
large values for convergence acceleration. 相似文献
994.
A subgroup H of finite group G is called pronormal in G if for every element x of G, H is conjugate to H
x
in 〈H, H
x
〉. A finite group G is called PRN-group if every cyclic subgroup of G of prime order or order 4 is pronormal in G. In this paper, we find all PRN-groups and classify minimal non-PRN-groups (non-PRN-group all of whose proper subgroups are PRN-groups). At the end of the paper, we also classify the finite group G, all of whose second maximal subgroups are PRN-groups. 相似文献
995.
电化学传感器在用于细胞实时监测过程中,电极界面污染严重影响其检测性能.通过将纳米光催化剂与电化学传感材料复合,构建光致清洁电化学传感器,为电极界面的高效及无损更新提供了新思路.然而光催化产生的活性氧自由基导致细胞损伤,限制了细胞培养及检测过程中电极界面的实时更新.为此,我们在PEDOT@CdS/TiO2/ITO可见光致更新电极表面旋涂明胶薄层,在保持电极良好的光致清洁和电化学传感性能同时,利用明胶薄层阻碍光催化产生的活性氧自由基扩散至细胞表面,显著降低了细胞损伤.此外,明胶优良的生物相容性有利于细胞的黏附及增殖.利用该电极,我们实现了人脐静脉内皮细胞(HUVECs)培养过程中,电极的在线更新以及细胞释放一氧化氮的实时监测. 相似文献
996.
997.
998.
The problem of a compressible gas flows over a flat plate with the velocity-slip and temperature-jump boundary conditions are being studied. The standard single- shooting method is applied to obtain the exact solutions for velocity and temperature profiles when the momentum and energy equations are weakly coupled. A double-shooting method is applied if these two equations are closely coupled. If the temperature affects the velocity directly, more significant velocity slip happens at locations closer to the plate’s leading edge, and inflections on the velocity profiles appear, indicating flows may become unstable. As a consequence, the temperature-jump and velocity-slip boundary conditions may trigger earlier flow transitions from a laminar to a turbulent flow state. 相似文献
999.
李朋杰 李智焕 陈志强 吴鸿毅 田正阳 蒋伟 李晶 冯骏 臧宏亮 刘强 牛晨阳 杨彪 陶龙春 张允 孙晓慧 王翔 刘洋 李奇特 楼建玲 李湘庆 华辉 江栋兴 叶沿林 《原子核物理评论》2017,34(2):177-183
介绍了利用硅探测器的脉冲形状甄别进行粒子鉴别的原理。详细叙述了基于数字化方法的脉冲形状甄别的实现。采样频率和位数是数字化方法的两个重要参数。对于硅探测器信号,采用100 MS/s,12 bit的Digitizer可以满足脉冲形状甄别法对时间分辨的要求。同时对该方法粒子鉴别的特征和能量阈值做了简要的分析和对比。粒子背面入射硅探测器的所得的阈值低于正面入射的情况。例如对于氖周围的同位素,背面入射情况的阈值约为100 MeV,为正面入射情况下鉴别阈值的二分之一,相当与ΔE-E方法中ΔE探测器厚度约为60 μm情况下的阈值。最后定性讨论了硅探测器的电阻率不均匀性和沟道效应对粒子鉴别性能的影响。In this paper Pulse Shape Discrimination(PSD) for silicon detector has been briefly introduced. The emerging digital method successfully applied to detector signal processing makes digital PSD method one of the most promising particle identification methods. Sampling frequency and the number of bits are two key parameters of digital method. For silicon detector signal, adopting 100 Ms/s, 12 bit Digitizer can satisfy the time resolution requirement of PSD method. The identification characteristic and energy threshold of this method have been discussed and compared with both front injection and rear injection cases. Energy threshold with rear injection usually is much lower than that with front injection. For example, around for Neon isotope energy threshold with rear injection is about 100 MeV which is only half of the threshold with front injection, also equivalent to thickness of about 60 μm silicon detector threshold in ΔE-E method. At the end the impact of silicon detector's resistivity nonuniformity and channel effect on the identification capacity of PSD method has been discussed in detail. 相似文献
1000.
There have already been several interface models for the analyses of thin interfacial layers in bonded materials. To distinguish their corresponding advantages or limitations, a comparative study is carried out, and a new constitutive-based interface model is proposed. Through numerical examinations, the limitations of typical models are clarified. It is found that the new interface model is an efficient and accurate model, by which both the traction and the displacement jumps across the modelled interface with the thickness of zero are allowed, and the stresses within the interfacial layer can also be analyzed. 相似文献