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41.
The European Physical Journal C - Hadron decay chains constitute one of the main sources of information on the QCD spectrum. We discuss the differences between several partial wave analysis...  相似文献   
42.
Yang  Tianzhi  Liu  Tao  Tang  Ye  Hou  Shuai  Lv  Xiaofei 《Nonlinear dynamics》2019,97(3):1937-1944
Nonlinear Dynamics - In this paper, a nonlinear energy sink and a negative stiffness element are integrated for achieving enhanced, passive, and adaptive vibration suppression for a pipe conveying...  相似文献   
43.
To develop efficient adsorbent materials for storage and separation of C2H2, an unprecedented supercage MOF, [Me2NH2]⋅[Zn3(ALP)(TDC)2.5]⋅3.5DMF⋅2 H2O ( 1 ) was constructed through medicinal molecule allopurinol (ALP) and S-containing 2,5-thiophenedicarboxylic acid (H2TDC). 1 contains a novel linear trinuclear cluster that is composed by ALP and carboxylates and forms a final uncommon 5-connected yfy topological framework. The framework possesses three types of interlinked cages decorated by rich functional sites, and reveals not only high adsorption capacity for C2H2 but also excellent selective separation for C2H2/CO2 and C2H2/CH4 at 298 K. Dynamic breakthrough experiments on C2H2/CO2 (1:1) mixture and C2H2/CH4 (1:1) mixture also demonstrated the potential of the material to separate C2H2 from CO2 or CH4 mixtures. Molecular simulations were also studied to identify the different CO2- and C2H2- binding sites in 1 , such as carboxylate groups, S atoms and carbonyl groups.  相似文献   
44.
Li  Yi  Hou  Yanren  Rong  Yao 《Numerical Algorithms》2020,84(3):1019-1048
Numerical Algorithms - In this paper, we present a second-order decoupled scheme based on the artificial compression method for the time-dependent Stokes-Darcy equations. This method not only...  相似文献   
45.
Wenhua Hou 《物理化学学报》2020,36(4):1912038-0
正与暴露非极性晶面的纳米材料相比,暴露极性面的纳米晶通常表现出不同寻常的性质~(1,2)。然而,极性晶面固有的偶极矩会导致表面结构出现多种变化~3,这对准确理解极性晶面结构并建立构效关系带来了巨大的挑战。当前研究晶面结构主要借助的是只能观测样品很小的一部分的电子显微镜技术,且该技术考察较轻的元素(如氢和氧)较为困难,因此亟须发展新的方法研究结构复杂的  相似文献   
46.
Let Ψn be the number of inequivalent self-dual codes in . We prove that , where . Let Δn be the number of inequivalent doubly even self-dual codes in . We also prove that .  相似文献   
47.
Summary  An increasingly important problem in exploratory data analysis and visualization is that of scale; more and more data sets are much too large to analyze using traditional techniques, either in terms of the number of variables or the number of records. One approach to addressing this problem is the development and use of multiresolution strategies, where we represent the data at different levels of abstraction or detail through aggregation and summarization. In this paper we present an overview of our recent and current activities in the development of a multiresolution exploratory visualization environment for large-scale multivariate data. We have developed visualization, interaction, and data management techniques for effectively dealing with data sets that contain millions of records and/or hundreds of dimensions, and propose methods for applying similar approaches to extend the system to handle nominal as well as ordinal data.  相似文献   
48.
惠斯登电桥精测电阻的方法和误差分析   总被引:1,自引:0,他引:1  
本文探讨了惠斯登电桥精确测量和校准电阻的方法,并分析了内插法和代换法的系统误差。  相似文献   
49.
Using Green's function method, we investigate the spin transport properties of armchair graphene nanoribbons (AG- NRs) under magnetic field and uniaxial strain. Our results show that it is very difficult to transform narrow AGNRs directly from semiconductor to spin gapless semiconductors (SGS) by applying magnetic fields. However, as a uniaxial strain is exerted on the nanoribbons, the AGNRs can transform to SGS by a small magnetic field. The combination mode be- tween magnetic field and uniaxial strain displays a nonmonotonic arch-pattern relationship. In addition, we find that the combination mode is associated with the widths of nanoribbons, which exhibits group behaviors.  相似文献   
50.
Insomnia is a common sleep disorder that is closely associated with the occurrence and deterioration of cardiovascular disease, depression and other diseases. The evaluation of pharmacological treatments for insomnia brings significant clinical implications. In this study, a total of 20 patients with mild insomnia and 75 healthy subjects as controls (HC) were included to explore alterations of electroencephalogram (EEG) complexity associated with insomnia and its pharmacological treatment by using multi-scale permutation entropy (MPE). All participants were recorded for two nights of polysomnography (PSG). The patients with mild insomnia received a placebo on the first night (Placebo) and temazepam on the second night (Temazepam), while the HCs had no sleep-related medication intake for either night. EEG recordings from each night were extracted and analyzed using MPE. The results showed that MPE decreased significantly from pre-lights-off to the period during sleep transition and then to the period after sleep onset, and also during the deepening of sleep stage in the HC group. Furthermore, results from the insomnia subjects showed that MPE values were significantly lower for the Temazepam night compared to MPE values for the Placebo night. Moreover, MPE values for the Temazepam night showed no correlation with age or gender. Our results indicated that EEG complexity, measured by MPE, may be utilized as an alternative approach to measure the impact of sleep medication on brain dynamics.  相似文献   
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