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Based on the combination of first-principles calculations and Boltzmann transport equation, we investigated the thermal transport properties of K 3 AuO and predicted a figure of merit ZT = 2.01 at 700 K with p-type doping. Such a high thermoelectric efficiency can be attributed to the ultra-low lattice thermal conductivity with a value of 0.48 Wm − 1 K − 1 at 300 K, and detailed research shows that the low lattice thermal conductivity arises from the small phonon group velocity and high scattering rates; moreover, the figure of merit ZT of p-type doped K 3 AuO can be maintained at around 2 in a relatively wide carrier concentration of 5.5 × 10 20 – 1.2 × 10 21 cm − 3 , which demonstrates the stable thermoelectric properties of K 3 AuO. [ABSTRACT FROM AUTHOR]

In this paper a time-explicit weak Galerkin finite element method is introduced and analyzed for parabolic equations. The main idea relies on the inclusion of a stabilization term in the temporal direction in addition to the usual static stabilization in the weak Galerkin framework. Both semi-discrete and fully-discrete schemes in time are presented, as well as their stability and error analysis. Numerical results are reported for this new explicit weak Galerkin finite element method. [ABSTRACT FROM AUTHOR]

The first-principles was employed to calculate the adsorption of Cs on (2 × 2) Al(Mg)0.5Ga0.5N and Al0.5 Ga(Mg)0.5N surfaces using density-functional theory within a plane-wave ultrasoft pseudopotential scheme. Then, the surface morphology, stability, work functions and Cs adsorptions of Al(Mg)0.5Ga0.5N and Al0.5 Ga(Mg)0.5N surfaces were investigated. The results reveal that Al(Mg)0.5Ga0.5N surface with Mg in the first layer was more suitable for ultraviolet cathode. The most stable adsorption site for adsorption of Cs on the Al(Mg)0.5Ga0.5N surface was found on N top. With the increase of Cs coverage, the interaction between Cs and atoms in the first layer of surface and that between Cs and Cs was enhanced, the surface dipole moment increased, the work function decreased, the carrier concentration and the absorption in visible light increased. When Cs coverage was greater than 0.5ML, the adsorption of Cs reached saturation, the deformation of surface structure appeared, the adsorption in visible light was greater than that in UV, and the surface was no longer suitable for UV detection. The results show that 0.5ML is the turning point of Cs coverage for the surface doped with Mg. [ABSTRACT FROM AUTHOR]

To promote the combination of mobile learning (m‐learning) in new courses contexts and improve students' learning outcomes, an integrated method of m‐learning and small private online course (SPOC)‐based flipped classroom was proposed and used for teaching the "hydrology" course at Xi'an University of Architecture and Technology (XAUAT). The offering of the new methodology was composed of preclass (knowledge acquisition), in‐class (knowledge internalization), and after‐class (knowledge application) stages, and the WeChat applet Mu classroom with m‐learning technology was adopted in the in‐class stage. To improve the teacher–student interactions and communication, several interactive activities were designed based on Mu classroom, including random roll calls, open questions, objective questions, discussion, and extended discussion. After using the integrated method, the average score of each final exam was improved significantly (p <.05), and the failed (<60) percentage was decreased significantly (p =.002 <.01). Positive correlation between the scores of in‐class quizzes and discussion and final exam were obtained (R2 =.530, p <.001), indicating that students' outcomes were greatly affected by mobile learning. Moreover, positive feedback from students' questionnaires confirmed that the integrated approach was effective and could motivate students' learning interests and knowledge understanding. [ABSTRACT FROM AUTHOR]