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The existing low-frequency magnetic parameter test is mainly based on impedance analysis,Its sample needs to be prepared into a ring,the hard materials are difficult to process into rings for testing. Small piece of material cannot be tested using impedance analysis because it is too small to be cut into a ring for testing. In this paper, the principle of impedance analysis and the basic theory of strip line be used, an empirical formula for the complex permeability of the magnetic bulk thick film material in the 0.1Ghz~0.6GHz frequency band is obtained through design and test by design simulation and physical fixture, it makes the testing of the complex permeability of thick film materials easier due to it avoid damage and ring cutting before testing.

In this paper, a novel approach for designing tapered periodic meta-surfaces (TPMS) is proposed for suppressing electromagnetic scattering from a trailing edge of a square metallic plate with a given thickness. The TPMS is realized by periodic square metallic patches with tapered dimensions at the direction perpendicular to the considered edge but keeping its period unchanged. Based on the geometric phase interaction, the mechanism of suppressing electromagnetic scattering is analyzed. The lossy material is not required in this design, so it doesn’t generate thermal energy and benefits infrared stealth of military objects. The backscattering properties from the trailing edge with the proposed TPMS loading are analyzed and compared with that of original trailing edge. It is observed that wide angular trailing edge scattering suppressing can be obtained and the average value of mono-static radar cross section (RCS) reduction is 10 dB for L-band, S-band and C-band. Finally, the bi-static RCS properties and energy distribution of the proposed structure are also proposed to explain the mechanism of the electromagnetic scattering suppression of the trailing edge employed with the TPMS.

Based on the principle of electromagnetic induction coupling of the wireless charging system, the main factors of the transmission efficiency is the coupling efficiency between the primary coil and the secondary coil. In order to improve the charging efficiency, NiCuZn ferrite material can be added in the wireless charging system. Thus, the wireless charging system can obtain high flux, and improve the transmission efficiency.

This paper presented the results of an investigation into effects of reagent removal by activated carbon, regrinding and combined depressant on the separation of chalcopyrite and galena. With the utilization of a selective collector called Z-200, a separation test of mixed copper-lead concentrate was conducted. By adopting single-stage roughing, two-stage scavenging, two-stage cleaning, a copper concentrate of containing 21.72% Cu, 7.81% Pb with the copper recovery of 91.28%, and a lead concentrate of containing 62.16% Pb, 0.82% Cu with the lead recovery of 95.24% were obtained.

Shaking-flask experiments and electrochemical tests were conducted to study the bioleaching of marmatite with mixed cultures of mesophilic bacteria. The effects of copper ions and the surfactant, o-phenylenediamines (OPD) on the bioleaching were investigated. The electrochemical mechanism of the bioleaching was researched through cyclic voltammetry and chronoamperometry. The results show that the decrease in leaching rate was associated with a passive film (elemental sulfur) formed on the surface of marmatite in the leaching course. It was found that, however, the passive film dissolved readily under high potential conditions or with the bacterial action. Especially, in the presence of bacteria, the decomposition of the passive film was accelerated by adding either copper ions or OPD, leading to a significant increase in the bioleaching rate of marmatite.

With regard to a deep-extend oxidized refractory lead-zinc ore from Yunnan province, containing 4.55% Pb and 17.09% Zn, a test study was carried out. By adopting single-stage roughing, single-stage scavenging, two-stage cleaning in the flotation of lead oxide ores, and single-stage cleaning, single-stage cleaning in the reverse flotation of zinc oxide ores, bulk concentrate of lead and zinc containing 36.60% Pb, 19.63% Zn with the Pb recovery of 82.45%, zinc concentrate containing 36.52% Zn, 0.44%Pb with the Zn recovery of 73.18% were obtained in the closed circuit experiment.

Terminals are important resources. They serve as a key role in transportation of people and goods in regional, national, and international commerce. Ensuring scheduled flight security and punctual is a basic requirement of civil aviation. In the premise that existing service resources unchanged, intelligent distribution and dispatch for passenger service resources in airport terminal building is an effective way to solve problems of delays for passengers. To study passenger departure processes in airport terminals, improve their operation, efficiencies, reduce delay, and improve service quality, a research on intelligent distribution for passenger service resources is developed using data integration methods, flow prediction method and intelligent simulation optimization algorithm.