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51.
Hua  Saixiang  Zhu  Huichao  Wang  Xiao  Wu  Mingyuan  Wu  Qingyun  Liu  Jiuyi  Yang  Jianjun  Zhang  Jianan 《Cellulose (London, England)》2022,29(13):7465-7475
Cellulose - Ultraviolet (UV) protective cotton fabric is a convenient and reliable way to protect human body from sunlight. Herein, a polymerizable UV-absorber,...  相似文献   
52.
Recently,the negative differential thermal resistance effect was discovered in a homojunction made of a negative thermal expansion material,which is very promising for realizing macroscopic thermal transistors.Similar to the Monte Carlo phonon simulation to deal with grain boundaries,we introduce positive temperature-dependent interface thermal resistance in the modified Lorentz gas model and find negative differential thermal resistance effect.In the homojunction,we reproduce a pair of equivalent negative differential thermal resistance effects in different temperature gradient directions.In the heterojunction,we realize the unidirectional negative differential thermal resistance effect,and it is accompanied by the super thermal rectification effect.Using this new way to achieve high-performance thermal devices is a new direction,and will provide extensive reference and guidance for designing thermal devices.  相似文献   
53.

We propose a scheme for teleportation of an arbitrary two-qubit state by using a Bell state as the quantum channel working together with an auxiliary qubit. Our scheme needs less entanglement resource, but at the cost of shortening teleportation distance. This is because that in order to successfully recover the teleported state, both sender and receiver need to implement quantum-gate operations on the shared auxiliary qubit. So, the auxiliary qubit must be close to both sender and receiver. Otherwise, the sender and receiver cannot carry out quantum-gate operations on it. Thus, our scheme is invalid for long-distance teleportation. But for short-distance teleportation, our scheme is an optimal choice because it requires less entanglement resource. From a practical point of view, our scheme is very promising for application in quantum teleportation on chip.

  相似文献   
54.
55.
通过改装多旋翼无人机(UAV)和搭载各类载荷以及联合地基观测设备对大柴旦地区大气、环境以及气溶胶参数进行测量。利用获得的数据资料,对该地区近地层气溶胶粒子数浓度(即单位体积空气中气溶胶粒子的数目)、消光系数以及气象要素等特征进行了分析。结果表明,在大柴旦地区,近地层气溶胶粒子数浓度日变化显著,呈现双峰形态,气溶胶粒子数浓度的变化范围为75~220 cm-3,消光系数的变化范围为0.004~0.038 km-1;当风速小于6 m/s时,气溶胶粒子数浓度与风速呈负相关关系;当风速大于6 m/s时,二者呈正相关关系;相对湿度对气溶胶粒子的影响较小,这可能是由于该地区以沙尘型气溶胶为主,吸湿性较弱。本研究基于多旋翼无人机探测平台,可以有效地获得近地层精细化大气、环境结构,有助于研究人员了解该地区气溶胶的结构、变化特征以及建立气溶胶模式,同时也为气溶胶及大气环境参数探测方法提供了技术支撑及思路拓展。  相似文献   
56.
Yang  Ruizhi  Nie  Chenxuan  Jin  Dan 《Nonlinear dynamics》2022,110(1):879-900
Nonlinear Dynamics - In this paper, we study a delayed diffusive predator–prey model with nonlocal competition in prey and habitat complexity. The local stability of coexisting equilibrium is...  相似文献   
57.
Fuzzy Optimization and Decision Making - Seepage equation in fissured porous media is a partial differential equation describing the variation of pressure of a given area over time. In traditional...  相似文献   
58.
This work is concerned with the extension of the Jacobi spectral Galerkin method to a class of nonlinear fractional pantograph differential equations. First, the fractional differential equation is converted to a nonlinear Volterra integral equation with weakly singular kernel. Second, we analyze the existence and uniqueness of solutions for the obtained integral equation. Then, the Galerkin method is used for solving the equivalent integral equation. The error estimates for the proposed method are also investigated. Finally, illustrative examples are presented to confirm our theoretical analysis.  相似文献   
59.
Yang  Tianyong  Wang  Bofu  Wu  Jianzhao  Lu  Zhiming  Zhou  Quan 《应用数学和力学(英文版)》2021,42(8):1183-1190
The horizontal convection in a square enclosure driven by a linear temperature profile along the bottom boundary is investigated numerically by using a finite difference method. The Prandtl number is fixed at 4.38, and the Rayleigh number Ra ranges from107 to 1011. The convective flow is steady at a relatively low Rayleigh number, and no thermal plume is observed, whereas it transits to be unsteady when the Rayleigh number increases beyond the critical value. The scaling law for the Nusselt number Nu changes from Rossby's scaling Nu ~ Ra~(1/5) in a steady regime to Nu ~ Ra~(1/4) in an unsteady regime, which agrees well with the theoretically predicted results. Accordingly,the Reynolds number Re scaling varies from Re ~ Ra~(3/11) to Re ~ Ra~(2/5). The investigation on the mean flows shows that the thermal and kinetic boundary layer thickness and the mean temperature in the bulk zone decrease with the increasing Ra. The intensity of fluctuating velocity increases with the increasing Ra.  相似文献   
60.
Acta Mathematicae Applicatae Sinica, English Series - The Hosoya index of a graph is the total number of matchings in it. And the Merrifleld-Simmons index is the total number of independent sets in...  相似文献   
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