Scanning Tunneling Electron Transport into a Kondo Lattice

We theoretically present the results for a scanning tunneling transport between a metallic tip and a Kondo lattice.We calculate the density of states(DOS)and the tunneling current and differential conductance(DC)under different conduction-fermion band hybridization and temperature in the Kondo lattice.It is found that the hybridization strength and temperature give asymmetric coherent peaks in the DOS separated by the Fermi energy.The corresponding current and DC intensity depend on the temperature and quantum interference effect among the c-electron and f-electron states in the Kondo lattice.     

Study of a magnetic alloy-loaded cavity for compact synchrotrons

Magnetic alloy(MA)-loaded cavities have been widely used in compact proton and heavy-ion synchrotrons,and the MA core is the key issue in their development.Chinese-produced MA has never yet been adopted as core material for an MA-loaded cavity.To use Chinese-produced MA as the core material,it is necessary to study its properties,and compare with MA material produced elsewhere.In this paper,the properties of several MA cores made of Chinese-produced material are measured.Based on the measured results,a schematic design is produced for a cavity which could obtain 1 kV gap voltage with less than 1.5 kW power dissipation in the frequency range of0.5-7 MHz.The difference between resonant frequencies obtained from simulation and analytical results is less than10%.     

Beam-based calibrations of the BPM offset at C-ADS Injector Ⅱ

Beam-based BPM offset calibration was carried out for Injector II at the C-ADS demonstration facility at the Institute of Modern Physics(IMP), Chinese Academy of Science(CAS). By using the steering coils integrated in the quadrupoles, the beam orbit can be effectively adjusted and BPM positions recorded at the Medium Energy Beam Transport of the Injector II Linac. The studies were done with a 2 m A, 2.1 Me V proton beam in pulsed mode.During the studies, the "null comparison method" was applied for the calibration. This method is less sensitive to errors compared with the traditional transmission matrix method. In addition, the quadrupole magnet's center can also be calibrated with this method.     

单层SbAs和BiSb的表面修饰调控

基于密度泛函理论的第一性原理计算,研究了V族二维层状材料SbAs和BiSb在全氢化和全氟化后体系的晶体结构、稳定性和电子结构.计算结果表明,全氢化后SbAs和BiSb由buckled结构转变为准平面结构,而全氟化后则转变为low-buckled结构.同时,本征、全氢化和全氟化的SbAs和BiSb均具有很好的稳定性,具备实验合成的可能性.电子结构的分析表明,全氢化和全氟化后SbAs和BiSb均由宽带隙半导体转变为窄带隙的直隙半导体,且其能带结构仍具有很好的线性色散.通过对准平面和low-buckled结构SbAs和BiSb电子结构的进一步分析,揭示了全氢化和全氟化后体系能带变化的原因.在h-BN衬底上的计算结果显示,由于两者间的弱耦合作用,使得全氢化和全氟化SbAs的直隙半导体特征得以保留,表明其在未来光电子设备等领域中具有广泛的应用前景.     

Dunkl’s theory and best approximation by entire functions of exponential type in L 2-metric with power weight

In this paper, we study the sharp Jackson inequality for the best approximation of f ∈L2,κ(Rd) by a subspace E2κ(σ)(SE2κ(σ)), which is a subspace of entire functions of exponential type(spherical exponential type) at most σ. Here L2,κ(Rd) denotes the space of all d-variate functions f endowed with the L2-norm with the weight v2κ(x) =ξ∈R, which is defined by a positive+|(ξ, x)|κ(ξ)subsystem R+ of a finite root system RRdand a function κ(ξ) : R → R+ invariant under the reflection group G(R) generated by R. In the case G(R) = Zd2, we get some exact results. Moreover,the deviation of best approximation by the subspace E2κ(σ)(SE2κ(σ)) of some class of the smooth functions in the space L2,κ(Rd) is obtained.     

Randomly weighted sums of subexponential random variables with application to capital allocation

We are interested in the tail behavior of the randomly weighted sum \( \sum _{i=1}^{n}\theta _{i}X_{i}\) , in which the primary random variables X ₁, …, X _n are real valued, independent and subexponentially distributed, while the random weights ?? ₁, …, ?? _n are nonnegative and arbitrarily dependent, but independent of X ₁, …, X _n . For various important cases, we prove that the tail probability of \(\sum _{i=1}^{n}\theta _{i}X_{i}\) is asymptotically equivalent to the sum of the tail probabilities of ?? ₁ X ₁, …, ?? _n X _n , which complies with the principle of a single big jump. An application to capital allocation is proposed.     

<Emphasis Type="Italic">Cis</Emphasis>/<Emphasis Type="Italic">trans</Emphasis> Fluorescent Recognition by Naphthalimide Dyes ⊂ CB [7] Assembly

A novel method to recognize cis/trans isomers was studied here. The naphthalimide dye as guest could bind with host cucurbit [7]uril (CB [7]) and 1:1 naphthalimide dye ? CB [7] assembly was formed. Moreover, this assembly was used as a fluorescent probe to recognized Fumaric acid (FA) and maleic acid (MA) via fluorescence titration. Two carboxyls in MA are in the same side, they could form stable interaction with the assembly and the fluorescence intensity decreased obviously when naphthalimide dye ? CB [7] was titrated by MA (nearly quenched in 1.5 equiv). But two carboxyls in FA are in opposite sides, the interaction between FA and the assembly was weak and not stable, and the fluorescence intensity changed inconspicuously when the assembly was titrated by FA.     

Topological phases and phase transitions on the honeycomb lattice

We investigate possible phase transitions among the different topological insulators in a honeycomb lattice under the combined influence of spin-orbit couplings and staggered magnetic flux. We observe a series of topological phase transitions when tuning the flux amplitude, and find topologically nontrivial phases with high Chern number or spin-Chern number. Through tuning the exchange field, we also find a new quantum state which exhibits the electronic properties of both the quantum spin Hall state and quantum anomalous Hall state. The topological characterization based on the Chern number and the spin-Chern number are in good agreement with the edge-state picture of various topological phases.     

Efficient statistical inference for partially nonlinear errors-in-variables models

In this paper, we consider the partially nonlinear errors-in-variables models when the non- parametric component is measured with additive error. The profile nonlinear least squares estimator of unknown parameter and the estimator of nonparametric component are constructed, and their asymptotic properties are derived under general assumptions. Finite sample performances of the proposed statistical inference procedures are illustrated by Monte Carlo simulation studies.     

求解非线性P_0互补问题的非单调磨光算法

提出了一种新的磨光函数,在分析它与已有磨光函数不同特性的基础上,研究了将它用于求解非线性P_0互补问题时,其磨光路径的存在性和连续性,进而设计了求解一类非线性P_0互补问题的非单调磨光算法.在适当的假设条件下,证明了该算法的全局收敛性和局部超线性收敛性.数值算例验证了算法的有效性.