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991.
992.
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
993.
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
994.
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
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Ying Tang Xiangjie Kong LiDe Fang Hongtao Wang 《Physica C: Superconductivity and its Applications》2011,471(23-24):1660-1663
Combined with the thermal analysis and phase identification, the influence of the B2O3 impurity in the original B powder on the phase formation of MgB2 during the sintering process was investigated. It is found that how the B2O3 impurity in the original B powder affects the sintering process of MgB2 depends on the reactivity of Mg particles in the original powder. If the Mg particles in the original powder are small and reactive enough, the B2O3 impurity could react with them before Mg melting during the sintering process and accelerate the solid–solid reaction between Mg and B. Otherwise, the B2O3 impurity could not react with Mg particles before Mg melting and depress the solid–solid reaction between Mg and B. 相似文献
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Bi-Yu Tang Dong-Lin Li Ping Chen Jian-Xiong Yi Li Wen Li-Ming Peng Wen-Jiang Ding 《Solid State Sciences》2010,12(5):845-850
Ab initio density functional theory (DFT) and density function perturbation theory (DFPT) have been used to investigate the thermal properties of the Al–Mg–Sc, Al–Mg–Zr and Al–Mg–Sc–Zr alloys over a wide range of temperature and pressure. Phonon dispersions are obtained at equilibrium and strained configurations by DFPT. Using the quasiharmonic approximation (QHA) for the free energy, several physical quantities of interest such as thermal Grüneisen parameter, heat capacity at constant pressure and at constant volume, thermal expansion coefficient, entropy, adiabatic bulk modulus and isothermal bulk modulus as a function of temperature and pressure are calculated and discussed. The present results show that the thermal expansion coefficient of the Al–Mg–Sc–Zr is far lower than that of Al–Mg–Sc and Al–Mg–Zr, and the variation features in the adiabatic bulk modulus and isothermal bulk modulus for the Al–Mg–Sc–Zr are also very different from that of Al–Mg–Sc and Al–Mg–Zr. 相似文献
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