Production and Storage of Energy with One-Dimensional Semiconductor Nanostructures

This article outlines state-of-the-art energy technologies, including production and storage, available to us through semiconductor nanomaterials. The nanostructure growth processes have been illustrated in detail, with emphasis on the latest developments in hierarchical and radial-composition modulated nanostructures. On the energy efficiency and generation part, light-emitting diodes, photovoltaics, photoelectrochemistry, thermoelectric, and fuel cells have been discussed. In the energy storage part, supercapacitors and lithium batteries have been discussed.     

Dual-channel tunable near-infrared absorption enhancement with graphene induced by coupled modes of topological interface states

The dual-channel nearly perfect absorption is realized by the coupled modes of topological interface states (TIS) in the near-infrared range. An all-dielectric layered heterostructure composed of photonic crystals (PhC)/graphene/PhC/graphene/PhC on GaAs substrate is proposed to excite the TIS at the interface of adjacent PhC with opposite topological properties. Based on finite element method (FEM) and transfer matrix method (TMM), the dual-channel absorption can be modulated by the periodic number of middle PhC, Fermi level of graphene, and angle of incident light (TE and TM polarizations). Especially, by fine-tuning the Fermi level of graphene around 0.4 eV, the absorption of both channels can be switched rapidly and synchronously. This design is hopefully integrated into silicon-based chips to control light.     

Noisy image segmentation based on nonlinear diffusion equation model

This paper addresses the segmentation problem in noisy image based on nonlinear diffusion equation model and proposes a new adaptive segmentation model based on gray-level image segmentation model. This model also can be extended to the vector value image segmentation. By virtue of the prior information of regions and boundary of image, a framework is established to construct different segmentation models using different probability density functions. A segmentation model exploiting Gauss probability density function is given in this paper. An efficient and unconditional stable algorithm based on locally one-dimensional (LOD) scheme is developed and it is used to segment the gray image and the vector values image. Comparing with existing classical models, the proposed approach gives the best performance.     

自旋为1/2的XY模型亚铁磁棱型链的物性和有序-无序竞争

利用不变本征算符法, 计算低温下自旋为1/2的XY模型一维亚铁磁棱型链系统的元激发谱, 讨论在此系统中不同的特殊情形下的元激发能量, 从而给出体系的三个临界磁场强度的解析解H_C1, H_C2, H_peak. 分析不同外磁场下 体系的磁化强度随温度的变化规律, 发现三个临界磁场强度的解析解H_C1, H_C2, H_peak是正确的, 并从三个元激发对磁化强度的贡献进行了说明. 低温下磁化强度随外磁场的变化呈现1/3磁化平台. 体系的磁化率随温度或者外磁场的变化都出现了双峰现象. 这说明双峰源于二聚体分子内电子自旋平行排列的铁磁交换作 用能和二聚体与单基体分子间电子自旋反平行排列的反铁磁交换作用能, 热无序能, 外磁场强度相关的自旋磁矩势能之间的竞争.     

水热法制备一维钛酸纳米材料及其在太阳光反射涂料中的应用研究

以微米级二氧化钛(P25)为原料,用水热法制备了一维纳米钛酸材料,分析了纳米钛酸的形貌、红外特性和晶体结构。并进一步对纳米钛酸作为太阳光反射涂料填料的效果进行了研究,其涂层在可见光波段(380～780 nm)范围平均反射率可达到76.15%,在红外波段(780～2500 nm)范围平均反射率可达47.34%。     

Transferring and Bounding Single Photon in Waveguide Controlled by Quantum Node Based on Atomic Ensemble

We study the scattering process of photons confined in a one-dimensional optical waveguide by a laser controlled atomic ensemble. The investigation leads to an alternative setup of quantum node controlling the coherent transfer of single photon in such one dimensional continuum. To exactly solve the effective scattering equations by using the discrete coordinate approach, we simulate the linear waveguide as a coupled resonator array at the high energy limit. We generally calculate the transmission coefficients and itsvanishing at resonace reflects the good controllability of our scheme. We also show that there exist two bound states to describe the localize photons around the cavity.     

The effects of cubic potentials on discrete breathers in a mixed Klein－Gordon /Fermi－Pasta－Ulam chain

Nonlinearity has a crucial impact on the symmetry properties of dynamical systems. This paper studies a one-dimensional mixed Klein--Gordon/Fermi--Pasta--Ulam diatomic chain using the expanded rotating plane-wave approximation and numerical calculations to determine the effect of cubic potentials on the symmetry properties of discrete breathers in this system. The results will be very useful to researchers in the field of numerical calculations on discrete breathers.     

爆炸膨胀环一维应力假定的分析与讨论

对爆炸膨胀环的运动过程和应力状态进行了理论分析,指出膨胀环在径向变形过程中其厚度减小 将引起内外壁的速度差,对膨胀环内外壁的速度差进行了分析。由于膨胀环内外壁速度差的存在必然造成复 杂应力状态,无法满足一维应力假定,由此推断出实验中利用外壁速度计算出的应力要略大于膨胀环内的平 均应力。利用LS-DYNA三维动力学有限元程序验证了理论分析结果,利用膨胀环外壁速度计算出的应力比 数值模拟给出的膨胀环内平均应力大1%左右。     

On the interaction between dislocations and cracks in one-dimensional hexagonal quasi-crystals

The solution of elasticity problems involving the interaction between dislocations and cracks plays a fundamental role in many practical and theoretical applications. Although elasticity problems involving dislocation or cracks in quasi-crystals have been investigated in many papers, the analysis is limited to a single defect. This paper investigates the interaction of defects in one-dimensional hexagonal quasi-crystals using the complex variable function method. The interaction force between two parallel dislocations is presented and the analytic solutions of elastic fields of interaction between a dislocation and a crack are obtained. A version of the well-known Peach－Koehler formula in one-dimensional hexagonal quasi-crystals is given.     

一维链状有机锡配位聚合物[(PhCH2)3Sn·(O2CC5H4N)·(H2O)]n的合成及晶体结构

[(PhCH₂)₃Sn·(O₂CC₅H₄N)·(H₂O)]_n was synthesized by the reaction of 4-pyridine car-boxylic acid with the tribenzyltin oxide and was characterized by IR,¹H NMR and MS.Its crystal structure was determined by X-ray single crystal diffraction.The crystal belongs to monoclinic.The space group P2₁/c with unit cell parameters a=1.2241(8)nm,b=0.9660(6)nm,c=2.3708(15)nm,β=102.722(12)°,V=2.734(3)nm³,Z =4,D_c=1.298g·cm^-3.In crystal,the tin atom rendered five-coordinate in a trigo nal bipyramidal structure which is bridged by 4-pyridine carboxy-late into one-dimensional chain polymers.