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991.
Quan Xu Zhe Song Hui Qian Mo Chen Pingye Wu Bocheng Bao 《The European physical journal. Special topics》2018,227(7-9):777-786
This paper investigates twin attractors in a two-neuron-based non-autonomous Hopfield neural network (HNN) through numerical analyses and hardware experiments. Stability analysis of the DC equilibrium point is executed and an unstable saddle-focus is found in the parameter region of interest. The stimulus-associated dynamical behaviors are numerically explored by bifurcation diagrams and dynamical map in two-dimensional parameter-space, from which coexisting twin attractors behavior can be observed with the variations of two stimulus-associated parameters. Moreover, breadboard experiment investigations are carried out, which effectively verify the numerical simulations. 相似文献
992.
Zhenhao Yan Guifang Liu Jinrui Wang Huaiqian Bao Zongzhen Zhang Xiao Zhang Baokun Han 《Entropy (Basel, Switzerland)》2021,23(8)
The domain adaptation problem in transfer learning has received extensive attention in recent years. The existing transfer model for solving domain alignment always assumes that the label space is completely shared between domains. However, this assumption is untrue in the actual industry and limits the application scope of the transfer model. Therefore, a universal domain method is proposed, which not only effectively reduces the problem of network failure caused by unknown fault types in the target domain but also breaks the premise of sharing the label space. The proposed framework takes into account the discrepancy of the fault features shown by different fault types and forms the feature center for fault diagnosis by extracting the features of samples of each fault type. Three optimization functions are added to solve the negative transfer problem when the model solves samples of unknown fault types. This study verifies the performance advantages of the framework for variable speed through experiments of multiple datasets. It can be seen from the experimental results that the proposed method has better fault diagnosis performance than related transfer methods for solving unknown mechanical faults. 相似文献
993.
Chunlin Bao Guoxing Zhu Mengqi Shen Miaomiao Liu Peng Xiao 《Crystal Research and Technology》2014,49(6):431-434
A facile microwave‐assistant route was developed for the synthesis of hybrid nanocrystals. Colloidal hybrid nanocrystals, Ag2S‐CdS, were prepared by using Ag2S nanocrystals and cadmium diethyldithiocarbamate as raw materials under microwave irradiation. The fast ion conductor, Ag2S nanocrystal, catalyzes the growth of CdS nano‐building blocks through a quasi solution‐solid‐solid mechanism. The ultraviolet‐visible absorption and photoluminescence spectra of the Ag2S‐CdS hybrid nanocrystals were investigated. One of the main advantages for this synthesis is the efficiency of dramatically reducing overall processing time. This report provides a new route for the growth of semiconductor hybrid nanocrystals based on Ag2S and may be extended to the preparation of other hybrid colloidal nanostructures. 相似文献
994.
Wen‐Bin Li Xiao‐Yue Yang Jing‐Tao Zhu Yu‐Chun Tu Bao‐Zhong Mu Hai‐Sheng Yu Xiang‐Jun Wei Yu‐Ying Huang Zhan‐Shan Wang 《Journal of synchrotron radiation》2014,21(3):561-567
A novel correction method for self‐absorption effects is proposed for extended X‐ray absorption fine structure (EXAFS) detected in the fluorescence mode on multilayer samples. The effects of refraction and multiple reflection at the interfaces are fully considered in this correction method. The correction is performed in k‐space before any further data analysis, and it can be applied to single‐layer or multilayer samples with flat surfaces and without thickness limit when the model parameters for the samples are known. The validity of this method is verified by the fluorescence EXAFS data collected for a Cr/C multilayer sample measured at different experimental geometries. 相似文献
995.
A synthetic strategy featuring efficient ruthenium-catalyzed asymmetric hydrogenation of racemic α-aryloxy cyclic ketone via dynamic kinetic resolution and palladium-catalyzed intramolecular reductive Heck cyclization has been developed for the asymmetric total synthesis of (-)-galanthamine (20.1%, 12 steps) and (-)-lycoramine (40.2%, 10 steps). 相似文献
996.
Li J Jiang G Yang B Dong X Feng L Lin S Chen F Ashraf M Jiang Y 《Analytical and bioanalytical chemistry》2012,402(3):1347-1354
Fusarium proliferatum was isolated as a major pathogen causing the Fusarium disease in harvested banana fruit. One of its major compounds, fusaric acid, was identified by high-performance liquid chromatography–electrospray
ionization mass spectrometry (HPLC–ESI–MS). Because the light intensity of the luminescent bacterium Vibrio qinghaiensis sp. Nov. Q67 can be inhibited by fusaric acid, the fusaric acid content of F. proliferatum was assessed and compared by both the HPLC and luminescent bacterium methods. Although both methods afforded almost similar
values of fusaric acid, the latter indicated slightly lower content than the former. Czapek medium was more suitable for the
growth of F. proliferatum and fusaric acid production than modified Richard medium, with an optimum pH of approximately 7.0. However, no significant
(P < 0.05) correlation was obtained between the fusaric acid production and growth of mycelia of F. proliferatum. The study suggests that the bioevaluation by use of the luminescent bacterium was effective in monitoring fusaric acid production
by F. proliferatum without expensive equipment. 相似文献
997.
An ion chromatography method has been proposed for the determination of three common inorganic anions(chloride,nitrate and sulfate) in anionic surfactants using a single pump system.The new system consists of an ion exclusion column,a concentrator column,and an anion exchange column connected in series via two 6-ports valves in a Dionex ICS-2000 ion chromatograph.The valves were switched several times for removing surfactants,concentrating and separating the three anions.The chromatographic conditions were optimized.Detection limits(S/N = 3) were in the range of 0.10-0.68μg/L.The relative standard deviations(RSDs) of peak area were less than 4.6%.The recoveries were in the range of 84.1-112.6%. 相似文献
998.
Xia BY Ng WT Wu HB Wang X Lou XW 《Angewandte Chemie (International ed. in English)》2012,51(29):7213-7216
In it for the long haul: Clusters of Pt nanowires (3D Pt nanoassemblies, Pt?NA) serve as an electrocatalyst for low-temperature fuel cells. These Pt nanoassemblies exhibit remarkably high stability following thousands of voltage cycles and good catalytic activity, when compared with a commercial Pt?catalyst and 20?%?wt Pt?catalyst supported on carbon black (20?% Pt/CB). 相似文献
999.
1000.
Liu B Hou L Wang YY Miao H Bao L Shi QZ 《Dalton transactions (Cambridge, England : 2003)》2012,41(11):3209-3213
A new dynamic porous coordination polymer (PCP) [Ni(dcpy)(bipy)(0.5)(H(2)O)]·1.5H(2)O (1) was synthesized by assembly of 3-(2',5'-dicarboxylphenyl)pyridine (dcpy), 4,4'-bipyridine (bipy) and NiSO(4)via solvothermal, hydrothermal and microwave methods, displaying a wavelike 2D stacked layer framework. Gas adsorption studies for 1 shows a high selective adsorption of CO(2) over other gases (N(2), CH(4) and CO). The adsorption capacity for N(2) can be moderately altered by different activation temperatures demonstrating the framework flexibility of 1. 相似文献