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Taiyuan, China

Taiyuan University of Technology is a university in Shanxi, People's Republic of China, under the authority of the provincial government. In 2012 it celebrated its 110th anniversary. It is listed officially as one of the 'Top 100 universities in China', according to the Chinese government. Wikipedia.

In this work, colloidal hexagonal-phase -NaYF4:Nd3+/ Yb3+/Ho3+/NaYF4:Nd3+/Yb3+ core/shell nanoparticles with intense visible upconversion emissions under 808-nm laser excitation were prepared. Compared with the core-only nanoparticles, a maximum 990-fold overall enhancement in the emission intensity of Ho3+ ions was achieved with the help of active-shell coating design, due to the significant increase in the near-infrared absorption and efficient energy transfer from Nd3+ primary-sensitizers to Ho3- activators via Yb3+ bridging sensitizers. The luminescence-enhancement effect exhibited a strong dependence on the doping concentrations of NaYF4:Nd3+/Yb3+ active-shell. The optimal concentrations of Nd3+ and Yb3+ ions in the active-shell layer were found to be 30 and 5 mol. %, respectively.Moreover, the upconversion emission intensity of NaYF4:Nd3+/Yb3+- coated nanoparticles was about 2.5 times higher than the one coated with a NaYF4:Nd3+ active-shell. © 2015 Optical Society of America. Source

Xue H.-B.,Taiyuan University of Technology
Annals of Physics | Year: 2013

We study theoretically the full counting statistics of electron transport through side-coupled double quantum dot (QD) based on an efficient particle-number-resolved master equation. It is demonstrated that the high-order cumulants of transport current are more sensitive to the quantum coherence than the average current, which can be used to probe the quantum coherence of the considered double QD system. Especially, quantum coherence plays a crucial role in determining whether the super-Poissonian noise occurs in the weak inter-dot hopping coupling regime depending on the corresponding QD-lead coupling, and the corresponding values of super-Poissonian noise can be relatively enhanced when considering the spins of conduction electrons. Moreover, this super-Poissonian noise bias range depends on the singly-occupied eigenstates of the system, which thus suggests a tunable super-Poissonian noise device. The occurrence-mechanism of super-Poissonian noise can be understood in terms of the interplay of quantum coherence and effective competition between fast-and-slow transport channels. © 2013 Elsevier Inc. Source

Teng K.,Taiyuan University of Technology
Nonlinear Analysis: Real World Applications | Year: 2013

In this paper, we establish the existence of two nontrivial solutions to a class of nonlocal hemivariational inequalities depending on two parameters. Our methods are based on critical point theory for non-differentiable functionals. © 2012 Published by Elsevier Ltd. Source

In this Letter, I present a versatile strategy to enhance the near-infrared to near-infrared (NIR-to-NIR) upconversion luminescence from sub-10-nm ultra-small LaF3:Yb3+/Tm3+ colloidal nanoparticles through lanthanide doping under 980 nm laser excitation. It is interesting that the NIR-to-NIR upconversion emission at 801 nm of LaF3:Yb3+/Tm3+ nanoparticles can be improved by increasing the Tm3+ doping concentration or by introducing another lanthanide activator (Er3+ or Ho3+) as a sensitizer. The luminescence enhancement effect showed a strong dependence on the doping concentrations of activator ions (Tm3+, Er3+, or Ho3+). Particularly, adding 1 mol. % Ho3+ ions into LaF3:Yb3+/Tm3+ nanoparticles induced a 2.85-fold enhancement in NIR 801 nm emission of Tm3+ ions. The related upconversion emission mechanisms were investigated and discussed. © 2015 Optical Society of America. Source

Teng K.,Taiyuan University of Technology
Nonlinear Analysis: Real World Applications | Year: 2015

In this paper we study the fractional Schrödinger type equations (-Δ)su+V(x)u=f(x,u),x ∈ ℝN. The nonlinearity f is assumed to be asymptotically linear or superquadratic growth. Using variant Fountain theorems, we prove the existence of infinitely many nontrivial high or small energy solutions. © 2014 Elsevier Ltd. All rights reserved. Source

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