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Development of 3D printing technology rapidly and widely used in machinery manufacturing. 3D printing business is much, but the efficient equipment is deficiency. Methods of 3D models collecting, processing and online displaying were studied. A 3D printing service platform was constructed based on Cloud computing technology. The service program was developed by ASP. The background of the platform was managed by MySQL database. CAD files were displayed on a HTML5 browser by WebGL. A 3D printer owner released the 3D printer information, users searched printers and uploaded models data. The models were manufactured by remote online printers. The platform provides excellent products manufacturing environment for 3D printer owners and users. Products and printers are full information sharing. The economic benefit is rich.

Research and application on wireless sensor networks in the future counterterrorism operations, including the target perception network, target guiding network, combat command control and the fire control network. Access to information and knowledge through the wireless sensor networks. Counterterrorism capacity can be upgraded, and precision strike over the horizon can be realized. The networks change the classical counterterrorism operations, reconnaissance and security mode. Qualnet simulation results show that packets loss rate of wireless sensor networks is small, and the peer to peer delay is short. The networks is suitable for counterterrorism operations environment.

In this paper, we initially report a new type of wax printing method for rapid fabrication of microfluidic devices in paper using a commercially available, cheap, minitype (home-use) CO2laser engraving machine. This method combines the two core operations commonly involved in all previous wax printing methods, namely the printing and heating (melting) of wax patterns into one operation of engraving home-made wax slice (put in contact with the surface of paper) by laser. The heat produced by the laser makes the wax being engraved melt and then spread into paper to form complete hydrophobic barriers which are used to define the hydrophilic flow channels or separate test microzones. Under the optimized experimental conditions, a typical device on a 3 cm × 3 cm piece of paper could be fabricated separately within ~320 sec and is ready for use once the engraving process is completed. The fabrication resolution and multiplexed analytical capability of the wax-patterned paper were additionally characterized.

Following the test work is difficult and complex in the modern radar maintenance support, the automatic testing of radar is necessary for the radar maintenance man. Radar transmitter test device is designed to test the work state and performance parameter of radar transmitter off-line or on-line, and means while it has expert default diagnosis system to analyze the key signals and locate typical faults. The test device is accordingly seen as a good means to middle radar maintenance support. The design of radar transmitter test device is given, its hardware solution and software solution is explained. And finally the reliability and expansibility of the device is discussed at last.

An effective and optimized method for synthesis silica sol nanospheres by hydrolysis and condensation of tetraethyl orthosilicate (TEOS) in the presence of aqueous alcohol solution with ammonia as catalyst was described. Under this experiment condition, monodisperse and uniform-size silica sol spheres with average diameters from 38-95nm were obtained. Here, we successfully controlled the size and shape of silica sol by fine adjusting the reaction parameters such as concentration of TEOS, value of R (H2O/TEOS) and ammonia concentration. On the basis of the experiment results, it was found that sphere size declined as the concentration of TEOS decreased. Also with the increment of ammonia concentration, the diameter of silica sol decreased slightly. However, higher R (H2O/TEOS) value would lead to larger sphere size in the range of 62-95nm. The resulting silica sol was determined by Field Emission Scanning Electron Microscopy (FE-SEM) and Fourier transformed infrared (FT-IR).

Highly monodisperse and uniform-size vinyl functiona-lized silica spheres were synthesized directly from vinyltriethoxysilane (VTES) in water/ethanol mixed solution, and in this system, we successfully controlled the size and shape of hybrid silica spheres by adjusting the concentrations of the precursor VTES and catalyst ammonia. On the basis of the experiment results, it was found that hybrid spheres size significantly increased as the increment of concentration of VTES. However, increasing ammonia concentration resulted in decreasing of diameter of hybrid silica spheres from 542 to 272 nm. The morphologies and structure were determined by Field Emission Scanning Electron Microscopy (FE-SEM) and Fourier transformed infrared (FT-IR).

The dry crushing of wasted printed circuit boards (PCBs) can make secondary contamination. In this paper, a wet comminution process is put forward to solve the difficulties. For the comminution product, the distributions of particle size, liberation degree and metal grade are analyzed, and for the product below 1mm, a wet metal beneficiation process combined with shaking table and flotation is employed. The results show that the Whole PCBs could be comminuted by the MX wet impact crusher, and the cumulative yield, liberation degree, total metal content and its copper grade of the product below 1mm is 83.49%, 97%, 83.46% and 20.50%respectively, and that metal concentrates could be beneficiated by XZY wet shaking table, and the yield, total metal weight, copper grade of the metal concentrate, the recovery of total metal and copper is 34.87%, 88.99%, 50.73%,79.90% and 78.07% respectively keeping the feeding concentration at 20% and water consumption in 1100L/h. For these metals included by shaking-table middling, the separation of both flotation and shaking table is carried out, and the total metal content and its copper grade, recovery in metal concentrate 2′ is 72.07% , 31.59% and62.04% respectively, meanwhile the copper grade of tailings in flotation and shaking table are decreased to 1.26% and 2.94%. The wet treatment process can effectively concentrate these valuable metals from waste PCBs.