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A series of ZnFe2O4/expanded graphite composites (EG/ZF) were prepared by the chemical precipitation method. The structure, composition and morphology of the as-prepared samples were characterized. Taking methylene blue (MB) as the simulate organic pollutant, the influences of various factors on the decontamination of the as-samples and their reusing performance were researched. The results showed that the decontamination activity of the EG/ZF composite with mass ratio of EG to ZF equal to 0.8 reaches the maximum in the MB solution of pH = 5, and has good performance for repeated use. What’s more, the possible mechanism of decontamination was studied further.

This paper analyzes and summarizes existing ring signcryption schemes, combined with self-certified cryptosystem and ring signcrypption, we proposed a self-certified ring signcryption based on Discrete Logarithm Problem. The scheme proposed not only guaranties ring signcrption’s anonymity, confidentiality, unforgeability and other security features, but also solves certificate management and key escrow issues, which can save storage space and communication cost. By removing bilinear pairings in the process of design, the efficiency of this scheme has been greatly improved. Concluded from the experimental results, this scheme has the advantages of high computational efficiency, high security, and low communication cost.

Aiming at the glass-to-metal seals serving in the Solar Thermal Power (STP), glass-to-metal vacuum brazed joints were studied. Scanning electron microscopy (SEM) and X-ray diffraction (XRD) analysis were performed to examine the microstructure and element contents of interface seam on the glass-to-metal vacuum brazed joints. Also, the compositional concentration of the interface seam was measured by using energy dispersive spectroscopy (EDS).

The experiments were carried out in a horizontal tube furnace using Al and NH3 as the source materials. The structure and morphology of the as-synthesized AlN nanowires are characterized by X-ray diffraction, scanning electron microscopies and Raman spectrum. The results indicated that the structure of synthesized AlN nanowire is hexagonal wurtzite structure, the length of the AlN nanowire is between several micrometers and the the average diameter is about 100 nm.The growth of the AlN nanowires can be expelained by vapor–liquid-solid mechanism.

In view of the family use wireless router in network turning on and the use process common breakdown, this paper systematically analyzes the wireless router causes of network failure, Six methods proposed to solve home wireless network router failure methods and procedures, And wireless network management and maintenance skills of daily, Shows the configuration of the wireless router and network connection troubleshooting typical case, Designed to help users quickly resolve wireless network failure.

In view of static wireless sensor node deployment efficiency low and dynamic wireless sensor node deployment non-uniform question, proposed based on a sensation environment object minute bunch with the motion proxy node gathering data method, effectively solves wireless sensor node deployment energy management and data collection and so on crucial the technical difficult problems, thus enhances the wireless sensor network the application value

The thermomechanical control processing (TMCP) was conducted through the adjustment of the rolling technological parameters to the test steel. The influence of the finishing temperature, cooling rate and alloying elements to the microstructure and mechanical properties was investigated by comprehensive utilization of grain refining strengthening and second phase strengthening.The results show that the microstructure was mainly composed of bainite, ferrite and second phase TiC; at the finishing temperature of 870°C, the yield strength was 596.7 MPa, the tensile strength reached 748.5 MPa, the elongation ratio was 20.17%; at high cooling rate of 16°C/s, the yield strength achieved 616.7 MPa, the tensile strength reached 785.5 MPa, the tensile ratio reduced for 0.78, and the elongation ratio enhanced to 20.92%. And the quantity of bainite increased with the raise of finishing temperature from 800°C to 870°C, which improved the hardness and wear resistance of the steel.

Urea-formaldehyde (UF) resins modified by montmorillonite(MMT) were prepared for coating materials of controlled-release fertilizers. The influences of MMT on the mechanical properties and fertilizer-permeation performance of UF resin were studied. The mechanical properties of modified UF resins are enhanced by the addition of MMT. The shear strength of modified UF resin with 3% MMT increases by nearly 20% and reaches the maximum. The urea permeation rate of modified UF resin membranes decreases with the increasing of membrane thickness and increases with the increasing of MMT content.

The counterforce wall and pedestral is a complex system. Computer aided design technology is used to design and analyze this reinforced and prestressed concrete structure. Firstly CAD design program is used to design a representative wall section as a separate component. It helps doing ultimate limit state calculation and serviceability limit state checking computation. The prestress on concrete induced by prestressing steel according to construction method is also computed. Secondly, a finite element program is used to analyze the whole system. The prestress computed by CAD design program is regarded as external load. Simulation technology is also described in this paper. The stress, strain and deformation of the whole prestressed system are calculated and checked. Moreover, dynamic structural analysis is done by finite element program. Then vibration frequencies and modes can be obtained. By combining CAD design with finite element program, this complex system can be designed reasonably and effectively.

Vacuum brazing of glass to Kovar alloy was carried out at 670~700°C using Cu-Ni-Sn-P brazing alloy. The holding time ranges from 5min to 30min. The shear stress was tested to evaluate the mechanical property of the vacuum brazed joints. The results showed the maximum shear stress was 11.6MPa when the brazing temperature was 680°C and holding time was 10min. In accordance with the welded structures, the finite element (FE) model of glass-to-metal brazed joints was established. As result, the shear tests on the lap joints in conjunction with FM analysis were used to optimize the glass-to-metal brazing technology. The above results provide the basis of design against damage and reliable estimation of glass-to-metal seals.

The glass-to-metal seals are usually used in the solar thermal power (STP) and electronic devices. However, the requirement of mechanical properties in the STP is much higher than that of electronic devices, because the glass-to-metal joints used in the STP need to have anti-fatigue performance in adition to higher static tensile strength. Under the repeated fluctuating loads, damage and failures of glass-to-metal seals in the STP often lead to serious consequences. Therefore, analysis of damage evolution and fracture behavior of glass-to-metal diffusion welded joints was performed in this paper. Firstly, the finite element (FE) model of glass-to-metal welded joints was established in accordance with the STP welded structures. And damage simulation was carried out by the FE software ABAQUS. Also, the work illustrates the modeling of damage in terms of traction versus separation to simulate crack propagation and introduces the use of traction-separation law as a damage initiation and evolution criteria. The microgram of damage distribution in the glass side near the interface could be characterized by Scanning Electron Microscope (SEM), which was compared with predictions obtained by finite element method (FEM) analysis. As result, the damage criteria on the lap joints in conjunction with FM analysis were used to optimize the glass-to-metal diffusion welding technology. The above results provide the basis of design against damage and reliable estimation of glass-to-metal seals.