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Objective： This study aimed to obtain suitable turbulence model for simulation infrared combined spouted bed numerical valued. Methods: Two equation models (SST k-ε and Realizable k-ε) were used for numerical simulation to obtain the performance parameters of the infrared spouted bed and the velocity, temperature and particle concentration distribution of the flow field in the drying chamber under different working conditions. The particle drying experiment of the infrared spouted bed was carried out. Results: When under the working conditions of air inlet velocity of infrared spouted bed drying chamber of 8 m/s and a temperature of 50 ℃, the values obtained by Realizable k-ε simulation are similar to those obtained by SST k-ε. The particle volume fraction distribution, velocity distribution and temperature distribution in the fluid domain of the drying chamber obtained by numerical simulation with the two turbulence models were similar, and the overall effect is good, which showed that the application of the two turbulence models to the equipment is feasible. The turbulence model of Realizable k-ε converged faster, but the stability of SST k-ε was better. Conclusion: The Realizable k-ε turbulence model is more reasonable to describe three-dimensional flow field of infrared spouted bed.

Aiming at the problem of network load balancing caused by the drastic fluctuation of network traffic caused by the access of a large number of terminal devices in the integrated heterogeneous network,an intelligent routing algorithm TDANRA based on reinforcement learning is proposed.Fine-grained and high-precision network traffic status parameters are obtained by software-defined network technology,TDANRA algorithm automatically generates real-time routing policies based on network traffic status and link bandwidth utilization threshold adjustment mechanism to guide the forwarding of network traffic,so as to solve the problem of drastic fluctuation of network traffic.Simulation results show that TDANRA algorithm can realize load ba-lancing of network traffic and reduce end-to-end transmission delay and data packet loss rate when a large number of terminal devices are connected to the network.

A series of silver-modified phosphotungstic acid catalysts AgxH3-xPW12O40 (x=1, 2, 3) were synthesized by incorporating silver nitrate into phosphotungstic acid. The structure, stability and acidity of the catalysts synthesized were characterized by Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermal gravimetric analysis-derivative thermogravimetric analysis (TGA-DTG) and 31P-TMPO magic-angle spinning nuclear magnetic resonance (31P-TMPO MAS-NMR) spectroscopy. The effects of various reaction parameters, such as methanol/oil molar ratio, amount of catalyst, reaction time, and reaction temperature on the catalytic transesterification of soybean oil and methanol with Ag2HPW12O40 were investigated. The results demonstrated that Ag2HPW12O40 had the best catalytic activity, superior biodiesel yield and excellent durability. The high catalytic activity of the catalyst was attributed to Brønsted-Lewis acid synergy. With 6 wt.% Ag2HPW12O40 catalyst, the yield of biodiesel reached 96.4% with a methanol/soybean oil molar ratio of 32/1, a reaction temperature of 150℃ and a reaction time of 20 h.

The Xitian large-scale W-Sn polymetallic ore field has been explored in recent years. It is found in jointed adjoining areas of the Nanling and Qinhang metallogenic belts which are located on the boundary between Hunan and Jiangxi provinces, and the junction of the Yangtze and Cathaysia blocks. At present, there are several debates about the formation ages of the ore bodies and nearby granitic intrusions. For example, is W-Sn mineralization related to either Indosinian or Yanshanian granites? Were numerous different types of ore bodies formed in the corresponding period? The separation of molybdenite minerals from two tin polymetallic deposits, Shantian greisen-quartz vein ore deposit and Tongmushan crushed zone-alterated rock ore deposit was undertaken and is reported in this paper. Re-Os model ages of molybdenite in these two deposits yielded (158.9±2.2) Ma (2SD) and (160.2±3.2) Ma (2SD), respectively, which show they were generated in the early stage of the late Jurassic period. According to statistical data of mica Ar-Ar and molybdenite Re-Os ages, Longshang, Heshuxia, Shantian and Tongmushan ore deposits were all formed during 150-160 Ma, which is the peak period of W-Sn large-scale mineralization related to granitic intrusions. Rhenium contents of the two molybdenite samples are 12.44×10-6 and 2.367×10-6, respectively, which suggests that metallogenic materials were derived from crustal-mantle mixture and crust. Combining with ninety data of rhenium contents in molybdenites of W-Sn polymetallic deposits closely related to granitoids in Nanling area in late Jurassic, the suggestion that a majority of metallogenic materials were derived from crust is given, with only a few of them derived from crust-mantle mixture.

The spin Hamiltonian parameters (SHPs) and the local structures for impurity W5+ in the Zn3(PO4)2ZnO nanopowders doped with WO3 under different concentrations are theoretically investigated using the perturbation calculations of these parameters. The exponential functions of the related quantities (cubic field parameter Dq, covalency factor N, relative tetragonal compression ratio τ and core polarisation constant κ) of concentration x with totally four adjustable coefficients a, b, c and d are adopted to fit the concentration dependences of the experimental d-d transition bands and SHPs. The impurity W5+ centres demonstrate moderate tetragonal compression ratios τ (∼3.1%) due to the Jahn–Teller effect. With the increase of WO3 concentration, Dq and N show moderately decreasing rules, while τ and κ exhibit slightly and moderately increasing tendencies with x, respectively. The mechanisms of the above concentration dependences of these quantities are analysed from the modifications of the local crystal-field strength and electron cloud density around the impurity W5+ with the variation of x. Present theoretical studies would be useful to the exploration of the structural properties and optical applications for WO3 doped Zn3(PO4)2ZnO nanopowders. [ABSTRACT FROM AUTHOR]