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排序方式: 共有4250条查询结果,搜索用时 15 毫秒
961.
Charles Ng Xiangju Kong Dr. Dongxia Wu Dr. Min Song Dr. Xiaohong Shi Xiaochun Xu Wei‐Han OuYang Rongxian He Prof. Xing‐Zhong Zhao Tom Lee Prof. F. Charles Brunicardi Dr. Mitch André Garcia Prof. Antoni Ribas Prof. Roger S. Lo Prof. Hsian‐Rong Tseng 《Angewandte Chemie (International ed. in English)》2013,52(12):3379-3383
962.
Xin Jia Jun-jun Wei Yuechan Kong Cheng-ming Li Jinlong Liu Liangxian Chen Fangyuan Sun Xinwei Wang 《Surface and interface analysis : SIA》2019,51(7):783-790
The cooling behavior of GaN-on-diamond substrate can be enhanced by reducing the thermal boundary resistance (TBR), which is mainly determined by the nature of interlayer. Although SiN film is considered as the primary candidate of dielectric layer, it is still needed to be optimized. In order to facilitate the understanding of the influence of dielectric layer on the TBR of GaN-on-Diamond substrate, aluminum nitride (AlN), and silicon nitride (SiN) film were compared systematically, both of which are 100 nm. The time-domain thermoreflectance (TDTR) measurements, adhesion evaluation, and microstructural analysis methods were adopted to analyse these two interlayers. The results show the TBR of SiN interlayer is as low as 38.5 ± 2.4 m2K GW−1, comparing with the value of 56.4 ± 5.5 m2K GW−1 for AlN interlayer. The difference of TBR between these two interlayers is elucidated by the diamond nucleation density, and the adhesion between the diamond film and GaN substrate, both of which are affected by the surface charge and chemical groups of the dielectric layer. 相似文献
963.
The light intensity distribution (LID) reflected by a planar corner-cube retroreflector array with the size of centimeter and above (PCCRA) is calculated based on the Collins formula, coordinate transformation matrixes and vector algebra. The expression can be used for the PCCRAs with different parameters and different complex optical systems described by ABCD matrix. The expression indicates that the LID of a PCCRA is much different from a single corner-cube retroreflector (CCR) with equivalent aperture. Computer simulations are applied to explain the expression clearly. The results show that the LID of the PCCRA is more homogeneous than the single CCR with equivalent aperture under circumstances of both normal incident light and oblique incident light. In addition, the expression is proved by comparing the simulation result of the PCCRA only comprising a single CCR and the previous experimental result. 相似文献
964.
965.
A sigma-edged design of intraocular lens (IOL) is proposed to minimize the reflected glare images associated with the edge. The optimal sigma inverse edge is investigated when pupil diameter is 5.0 mm by the established Escudero-Sanz's wide angle model. The non-sequential ray tracing program of Zemax-EE (Zemax Development Corp., San Diego, USA) is used to investigate the sigma edge of reducing the potential for edge glare phenomena. The results show that sigma-edged design can significantly reduce the reflected glare intensity on retina if the angle of its inverse edge is taken from 20 to 70 degrees. 相似文献
966.
结合卫星“微型核”的特点,研究电介质薄膜中的导热机理以及薄膜厚度对导热系数的影响.以结构较为简单、具有可靠势能函数,实验数据较为丰富和可靠的氩的(fcc)晶体为模型,采用平衡分子动力学方法(EMD)和各向异性非平衡分子动力学方法(NEMD)计算了氩晶体及其法向薄膜的热导率,并与实验结果进行比较.模拟结果表明,氩晶体纳米薄膜的热导率显著小于对应大体积晶体的实验值,具有明显的尺寸效应.在氩薄膜厚度为2.124—5.310nm的模拟范围内,薄膜的法向热导率随着薄膜厚度的增加而呈近似线性增加.
关键词:
热导率
纳米薄膜
尺寸效应
平衡分子动力学
非平衡分子动力学 相似文献
967.
Boris P. Belinskiy John R. Graef Lingju Kong 《Journal of Nonlinear Modeling and Analysis》2022,4(1):103-113
A fin is traditionally thought of as an extension of a surface to facilitate the transfer of heat away from a larger body to which it is attached. In this paper, the authors study some mathematical properties of a nonlinear heat transfer model for a fin and its relation to an associated linear model. Specifically, they prove that the solution exists and is unique, and they determine bounds for the temperature. Further, they prove the monotonicity of the temperature distribution, and they obtain an estimate for the maximal difference between the temperatures as determined by the nonlinear and linear models. 相似文献
968.
In the previous studies, the phenomenon that the interstitial fluid(ISF) can flow along tunica adventitia of the arteries and veins in both human and animal bodies was reported. On the basis of these studies, this paper aims to:(i) summarize the basic properties of the ISF flows in the walls of arteries and veins,(ii) combine the basic properties with axiomaticism and abstract the axiom for ISF flows, and(iii) propose three fundamental laws of the ISF flow,(i.e., the existence law, the homotropic law and the reverse law). The three laws provide solid theoretical basement for exploring the kinematic patterns of interstitial fluid flow in the cardiovascular system. 相似文献
969.
Erqiang Liu Jianguo Wu Huaying Li Haitao Liu Gesheng Xiao Qiang Shen Lingyu Kong Jinbao Lin 《Journal of polymer science. Part A, Polymer chemistry》2021,59(16):1795-1806
In this study, the viscoelastic behavior of a polyamide 12 (PA12) polymer was evaluated using instrumented indentation technology based on a rheological model. The creep compliance and retardation spectra were obtained to analyze the viscoelastic response during the holding stage according to the rheological model under different preloading conditions. The results showed that the viscoelastic responses were independent of the indentation depth or load under step loading conditions. However, the creep compliance increases, and the peak intensity of the retardation spectrum decreases with a decrease in the preloading rate owing to the structural relaxation observed during the preloading stage under ramp loading conditions. Furthermore, softening dispersion can be completed during the loading stage under continuous stiffness measurement (CSM) conditions. As the preloading strain rate changes, the peak of the retardation spectrum gradually decreases until it disappears completely. Moreover, studies on indentation creep using the CSM method are challenging because of the complicated viscoelastic response observed during the preloading stage. 相似文献
970.
Fulin Chen Naihuan Jing Fei Kong Shaobin Tan 《Journal of Pure and Applied Algebra》2022,226(1):106814
In this paper we introduce a new quantum algebra which specializes to the 2-toroidal Lie algebra of type . We prove that this quantum toroidal algebra has a natural triangular decomposition, a (topological) Hopf algebra structure and a vertex operator realization. 相似文献