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61.
Wu Jinxiu Qi Yuanhao Liu Zhaogang Jia Huiling Hu Yanhong Feng Fushan 《Journal of solution chemistry》2022,51(1):14-30
Journal of Solution Chemistry - The interaction between Dy(Ш)/Rutin complexes and bovine serum albumin (BSA) was studied by fluorescence, ultraviolet (UV) absorption, three-dimensional... 相似文献
62.
Li Yang Fu Xuan Li Xu-Xin Zhang Fang Wu Qiang Wang Yun Yan Ze-Yi 《Journal of Radioanalytical and Nuclear Chemistry》2022,331(2):877-888
Journal of Radioanalytical and Nuclear Chemistry - In this study, the imidazole-based poly(ionic liquid)s (PILs) synthesized by one step method has been applied for the enrichment and recovery of... 相似文献
63.
GPS误差模型参数估计的Hopfield神经网络方法 总被引:2,自引:2,他引:2
本文首先建立了GPS误差模型。然后,利用Hopfield神经网络(HNN)方法对误差模型参数进行了估计,并给出了其硬件实现方法。将估计结果与传统的最小二乘(LS)估计进行比较,证明了神经网络方法的有效性。 相似文献
64.
This paper reports a numerical study on buoyancy-aided steady convection heat transfer from a horizontal cylinder situated in a vertical adiabatic duct. Numerical results have been generated forH
1/D=2.5, 4, 8,H/D=8, 16, 24,S/D=2, 4, 6, 20Re60, andRi up to 4. The placing of a horizontal cylinder in a vertical duct of smaller width results in significantly enhanced pure forced convection due to the blockage effect, but degrades appreciably the extent of buoyancy-aided enhancement in the heat transfer rate. Nevertheless, the presence of a vertical duct leads to an overall enhancement of mixed convection heat transfer coefficient relative to that without the confining duct. Moreover, the average Nusselt number is rather insensitive to the variation of either the position of the cylinder in the duct or the duct height in the investigated ranges of these geometric parameters.Dieser Artikel beschreibt eine numerische Studie über auftriebsunterstützte konvektive Wärmeübertragung von einem horizontalen Zylinder der in einem vertikalen adiabaten Kanal positioniert ist. Die numerischen Ergebnisse sind fürH
1/D=2, 5, 4, 8,H/D=8, 16, 24,S/D=2, 4, 6 sowie 20Re60 undRi bis 4 berechnet worden. Die Anordnung des horizontalen Zylinders in einem schmaleren vertikalen Kanal führt auf Grund des Blockierungs-effektes zu einem deutlichen Anstieg der reinen Zwangskonvektion. Aber sie verschlechtert deutlich den Betrag der auftriebsbedingten Steigerung in der Wärmeübergangsrate. Trotzdem führt die Anwesenheit des vertikalen Kanals insgesamt zu einer Steigerung des Wärmeübergangskoeffizienten bei Mischkonvektion im Vergleich zur Abwesenheit des begrenzenden Kanals. Des weiteren ist die durchschnittliche Nusseltzahl von der Variation der Zylinderposition im Kanal oder der Kanalhöhe abhängig. 相似文献
65.
66.
Theodore Yao-tsu Wu 《Acta Mechanica Sinica》1995,11(4):289-306
The bidirectional long-wave model introduced by Wu (1994)[1] and Yih & Wu (1995)[2] is applied to evaluate interactions between multiple solitary waves progressing in both directions in a uniform channel of
rectangular cross-section and undergoing collisions of two classes, one being head-on and the other overtaking collisions
between these solitons. For a binary head-on collision, the two interacting solitary waves are shown to merge during a phase-locking
period from which they reemerge separated, each asymptotically recovering its own initial identity while both being retarded
in phase from their original pathlines. For a binary overtaking collision between a soliton of height α1 overtaking a weaker one of height α1, the two solition peaks are shown to either pass through each other or remain separated throughout the encounter according
as α1/α2 or <3, respectively. With no phase locking during the overtaking, the two solitary waves re-emerge afterwards with their
initial forms recovered and with the stronger wave being advanced whereas the weaker one retarded in phase from their original
pathlines. By extension, the theory is generalized to apply to uniform channels of arbitrary cross-sectional shape.
The Inaugural Pei-Yuan Chou Memorial Lecture, presented at The Sixth Asian Congress of Fluid Mechanics. Singapore, 21–26 May
1995 相似文献
67.
This paper deals with non-linear oscillation of a conservative system having inertia and static non-linearities. By combining the linearization of the governing equation with the method of harmonic balance, we establish analytical approximate solutions for the non-linear oscillations of the system. Unlike the classical harmonic balance method, linearization is performed prior to proceeding with harmonic balancing, thus resulting in a set of linear algebraic equations instead of one of non-linear algebraic equations. Hence, we are able to establish analytical approximate formulas for the exact frequency and periodic solution. These analytical approximate formulas show excellent agreement with the exact solutions, and are valid for small as well as large amplitudes of oscillation. 相似文献
68.
大理岩非分叉断裂的随机分形模型 总被引:1,自引:0,他引:1
本文建立了大理岩沿晶、穿晶及沿晶穿晶偶合断裂的随机分形模型,该模型能与大理岩的整体晶态结构自洽,且模型的分维值与测量值有很好的吻合。 相似文献
69.
QixiangWang GuoqingNing FeiWei GuohuaLuo 《中国颗粒学报》2003,1(6):253-257
Multi-walled carbon nanotubes (MWNTs) with 20 nm outer diameter were prepared by chemical vapor deposition of ethylene using ultrafine surface-modified acicular α-Fe catalyst particles.The growth mechanism of MWNTs on the larger catalyst particles are attributed to the interaction between the Fe nanoparticles with the surface-modified silica layer.This interaction-mediated growth mechanism is illustrated by studying the electronic,atomic and crystal properties of surface-modified catalysts and MWNTs products by characterization with X-ray diffraction (XRD),transmission electron microscopy (TEM),high resolution transmission electron microscopy (HRTEM),thermal gravimetric analysis (TGA) and Raman spectra. 相似文献
70.
Wu Xuemou 《应用数学和力学(英文版)》1980,1(1):63-70
This paper is concerned with operator variation from the transforming point of view, and presents some new concepts and new relations. Related problems and concepts include: convex operator, reciprocity set, reciprocity principles, unilateral variation principles, (H, H
1,H
2) — generalized solution and operator-differential equation, etc..Variation principle and variation method is a sort of basic concept and method in the analysis of many problems concerning mathematics, mechanics, physics and control theory. The change and transformation of variation or stationary value relations is the most fundamental form and process of these princeples and methods. This paper analyzes some properties of operator variation and stationary value from the transforming point of view and presents some new concepts, unifiedly treats and extends the reciprocity theorem of classical variation, variation theorem of quadratic functional and unilateral variation principles. Furthermore, we investigate the calculus of normed ring and the solution of a sort of operator differential equation. 相似文献