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991.
Nonlinear Dynamics - Based on an analysis of the continuity of discrete transition functions, this paper presents a new approach for characterizing piecewise affine (PWA) systems’ regions of... 相似文献
992.
A new TfOH-mediated reaction of ynamides with nitriles as nucleophiles has been developed. The reaction works efficiently under mild reaction conditions to afford a new class of α-acylaminoenamides readily via the intermediacy of keteniminium ion. The reaction displays generality and a broad substrates scope. Additionally, the α-acylaminoenamides could be transformed to highly substituted pyridine, 4-aminopyrimidine or isoquinoline cores. 相似文献
993.
Catalysis Surveys from Asia - Co3O4 catalyst derived from Co-MOFs demonstrated rich active sites in the catalytic reaction. In this paper, we prepared the rod-like Co3O4 catalysts by calcining... 相似文献
994.
995.
Two series of novel liquid crystalline materials were synthesized: 2-(2,3-difluoro-4-alkoxyphenyl)-5-[4-(4-alkylcyclohexyl)phenyl]-1,3-dioxanes (A m-n and 2-(2,3-difluoro-4-alkylphenyl)-5-[4-(4-alkylcyclohexyl)phenyl]-1,3-dioxanes (B m-n ). Their mesmorphic properties were characterized by polarizing optical microscopy and differential scanning calorimetry. All these compounds exhibit broad mesomorphic phases, and most of them show wide smectic C phases and the phase sequence Cr-SmC-SmA-N-I. The relationship between properties and chemical structures is discussed in detail. 相似文献
996.
997.
Xu Tang Juan Han Yun Wang Liang Ni Longhua Li Lei Wang Wenli Zhang 《Tetrahedron》2017,73(10):1367-1373
A new on-off fluorescent probe 1 for Cu2+ based on Schiff base compound was designed and synthesized by one-step reaction. The single probe 1 exhibited strong green fluorescence emission. A fluorescence quenching effect and faint color change were observed as soon as the Cu2+ was added to the probe system in H2O/EtOH (v/v = 8:2, HEPES buffer, 0.05 M, pH = 7.4) solution. Other common metal cations did not cause the changes in the fluorescence and color of the probe 1. The optical properties were studied by the fluorescence emission and UV–Vis spectra. Meanwhile, the geometry optimizations of probe 1 and the [1-Cu2+] coordination complexes were also carried out by DFT using the Gaussian 09 program, in which the B3LYP function was used. Based on experimental measurement and theoretical analysis, we can know that the combination ratio of the probe and Cu2+ is 2:1 and the limit of detection (LOD) is as low as 5.3 × 10?9 M Besides, the probe 1 was also used to analyze the Cu2+ in living cells. 相似文献
998.
In this paper, artificial boundary conditions are designed for out-of-plane waves in penta-graphene, a newly proposed allotrope of carbon. By matching the dispersion relation for acoustic branch phonons in the long wave limit, we determine parameters in proposed linear constraints among displacements and velocities at the boundary and nearby atoms. Reflection analysis for normal incidences and a numerical test demonstrate the effectiveness of the artificial boundary conditions. These conditions may be used for studying mechanical behaviours of the novel complex lattice of penta-graphene. 相似文献
999.
Microchimica Acta - The authors are presenting an electrochemical aptasensor for tumor necrosis factor-alpha (TNF-α) detection that is aided by the use of magnetic nanoparticles (NPs) and two... 相似文献
1000.