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81.
Acta Mathematicae Applicatae Sinica, English Series - In this paper, we consider the statistical inferences in a partially linear model when the model error follows an autoregressive process. A... 相似文献
82.
Nonlinear Dynamics - Contact and friction phenomena in clearance joint adversely affect mechanical performance and may even result in chaos within the mechanism. Analysis of nonlinear... 相似文献
83.
Cao Hongmei Deng Shenzhen Tie Zhiwei Tian Jinlei Liu Lili Niu Zhiqiang 《中国科学:化学(英文版)》2022,65(9):1725-1732
Science China Chemistry - Synchronously reducing/self-assembling strategy on Zn substrate was designed to fabricate large-area cation-doped hydrated V2O5/multi-walled carbon nanotube (D-HVO/MWCNT)... 相似文献
84.
Covalent organic frameworks(COFs) are emerging photocatalysts for hydrogen evolution in water splitting in recent years. They offer a pre-designable platform to design tailor-made structures and chemically adjustable functionality in terms of photocatalysis. In this review, we summarize the recent striking progress of COF-based photocatalysts in design and synthesis. Firstly, different approaches to functionalizing building blocks, diversifying linkages, extending π-conjugation and establishing D-A conjugation are illustrated for enhancing photocatalytic activity. Next, post-modification of backbones and pores is detailed for emphasizing the synergistic catalytic uniqueness of COFs. Besides, the strategy of preparing COF-related composites with various semiconductors is outlined for optimizing the electronic properties. Finally, we conclude with the current challenges and promising opportunities for the exploration of new COF-based photocatalysts. 相似文献
85.
An oriented tetrahedron defined on four vertices is a set of four cyclic triples with the property that any ordered pair of vertices is contained in exactly one of the cyclic triples. A tetrahedral quadruple system of order with index , denoted by , is a pair , where is an ‐set and is a set of oriented tetrahedra (blocks) such that every cyclic triple on is contained in exactly members of . A is pure if there do not exist two blocks with the same vertex set. When , the spectrum of a pure TQS has been completely determined by Ji. In this paper, we show that there exists a pure if and only if and . A corollary is that a simple also exists if and only if and . 相似文献
86.
In recent years, clapping synchronization between individuals has been widely studied as one of the typical synchronization phenomena. In this paper, we aim to reveal the synchronization mechanism of clapping interactions by observing two individuals’ clapping rhythms in a series of experiments. We find that the two synchronizing clapping rhythm series exhibit long-range cross-correlations(LRCCs);that is, the interaction of clapping rhythms can be seen as a strong-anticipation process. Previous studies have demonstrated that the interactions in local timescales or global matching in statistical structures of fluctuation in long timescales can be sources of the strong-anticipation process. However, the origin of the strong anticipation process often appears elusive in many complex systems. Here, we find that the clapping synchronization process may result from the local interaction between two clapping individuals and may result from the more global coordination between two clapping individuals. We introduce two stochastic models for mutually interacting clapping individuals that generate the LRCCs and prove theoretically that the generation of clapping synchronization process needs to consider both local interaction and global matching. This study provides a statistical framework for studying the internal synchronization mechanism of other complex systems. Our theoretical model can also be applied to study the dynamics of other complex systems with the LRCCs, including finance, transportation, and climate. 相似文献
87.
将一种人工合成的无机聚合物——蒙脱石皂石黏土(smectite,Sm)应用于基质辅助激光解吸电离飞行时间质谱分析(matrix-assisted laser desorption/ionization time of flight mass spectrometry, MALDI-TOF-MS),以检测糖类化合物。 将传统的有机基质2,4,6-三羟基苯乙酮(trihydroxyacetophenone, THAP)与阳离子交换后的皂石黏土混合制备成新型复合基质,应用于糖类化合物的检测。通过比较不同的制样方法,测定不同分子直径的糖类化合物,发现由于受复合基质晶面间距的限制,只有小分子糖类化合物能进入晶面间隙充分接触有机基质并被离子化,从而实现对小分子糖类化合物的选择性检测。 相似文献
88.
The purpose of this article is to investigate high‐order numerical approximations of scalar conservation laws with nonlocal viscous term. The viscous term is given in the form of convolution in space variable. With the help of the characteristic of viscous term, we design a semidiscrete local discontinuous Galerkin (LDG) method to solve the nonlocal model. We prove stability and convergence of semidiscrete LDG method in L2 norm. The theoretical analysis reveals that the present numerical scheme is stable with optimal convergence order for the linear case, and it is stable with sub‐optimal convergence order for nonlinear case. To demonstrate the validity and accuracy of our scheme, we test the Burgers equation with two typical nonlocal fractional viscous terms. The numerical results show the convergence order accuracy in space for both linear and nonlinear cases. Some numerical simulations are provided to show the robustness and effectiveness of the present numerical scheme. 相似文献
89.
Liu Cungen Gao Chuang Liu Xiaoping Wang Huanqing Zhou Yucheng 《Nonlinear dynamics》2021,104(4):3655-3670
Nonlinear Dynamics - This paper is devoted to the adaptive finite-time prescribed performance control (FTPPC) for stochastic nonlinear systems with unknown virtual control coefficients (UVCCs),... 相似文献
90.
Dapeng Liu Binod R. Giri Milán Szőri Béla Viskolcz Et-touhami Es-sebbar Aamir Farooq 《Proceedings of the Combustion Institute》2021,38(1):967-976
NOx mitigation is a central focus of combustion technologies with increasingly stringent emission regulations. NOx can also enhance the autoignition of hydrocarbon fuels and can promote soot oxidation. The reaction between allyl radical (C3H5) and NOx plays an important role in the oxidation kinetics of propene. In this work, we measured the absolute rate coefficients for the redox reaction between C3H5 and NOx over the temperature range of 1000–1252 K and pressure range of 1.5–5.0 bar using a shock tube and UV laser absorption technique. We produced C3H5 by shock heating of C3H5I behind reflected shock waves. Using a Ti:Sapphire laser system with frequency quadrupling, we monitored the kinetics of C3H5 at 220 nm. Unlike low-temperature chemistry, the two target reactions, C3H5 + NO → products (R1) and C3H5 + NO2 → products (R2), exhibited a strong positive temperature dependence for this radical-radical type reaction. However, these reactions did not show any pressure dependence over the pressure range of 1.5–5.0 bar, indicating that the measured rate coefficients are close to the high-pressure limit. The measured values of the rate coefficients resulted in the following Arrhenius expressions (in unit of cm3/molecule/s):To our knowledge, these are the first high-temperature measurements of allyl + NOx reactions. The reported data will be highly useful in understanding the interaction of NOx with resonantly stabilized radicals as well as the mutual sensitization effect of NOx on hydrocarbon fuels. 相似文献