Advanced Materials Research Vols. 482-484

Abstract: The 5.6km long Yellow River Bridge is the control engineering of the Baoshu highway. Design documents indicate that the adhesive layer uses modified emulsified asphalt and the spray waterproof layer is over the adhesive layer. Because the Yellow River Bridge’s single-span is too large the bridge deck is too longer, the design of waterproof bonding layer s can easily lead to the early destruction of deck. Based on the careful analysis and investigation, project and the technical advisory group decided to adopt SBS modified bitumen Synchronous Chip Seal instead of modified asphalt emulsion waterproof bonding layer. And the engineering project controls the construction process to control construction effects. This method effectively solves the phenomenon of sticking wheel. After construction, the synchronization gravel seal bond strength test, the results show that average bond strength is 0.58MPa at 22 °C, greater than the standard specification’s requirement. Construction effect is good of Baoshu highway simultaneous gravel seal.

Abstract: The management system of the double switching signals’ design is to achieve the persistent light warning effect by switching to the other main signal automatically when the car’s turning signal is broken. This self-bringing manage system will automatically record the specific location of the broken signal light, and will notice the conservator or the maintenance worker to keep in repair the signal light. Thus, this way can improve managerial effectiveness and shorten examining time. This design adopts single chip or logic control chip to realize automatic switch; and transfers signals between turning signals and main control system according to low voltage power line transmission technology or wireless transmission technology. Based on this, the system will keep working constantly, and facilitate conservators to find stoppages and solve them efficiently.

Abstract: Based on the theory of gearing and differential geometry, a CNC hypoid generator mathematical model for spiral bevel has been developed. A mathematical model of a spiral bevel gear-tooth surface based on the CNC Gleason hypoid gear generator mechanism is proposed in the paper. The simulation of the spiral bevel gear is presented according to the developed machining mathematical model. A numerical example is provided to illustrate the implementation of the developed mathematic models.

Abstract: Transparent flame-retardant ceramic coatings were prepared via sol-gel method by siloxane and silica sol as the matrix, organophosphates (M102B) as the fire retardant agent, solvent and other additives. Results showed that such coatings had excellent physical and chemical properties. When the weight ratio of M102B reached 3% in the coatings and the cover weight reached 2g/100cm² on the wood, the limit time of fire-endurance could get to 64 min. The decompose processes and formation of the flame-retardant coatings were investigated by TGA and FTIR.

Abstract: In this paper, the crystal growth, ceramic preparation and performance of Yb: YAG was studied systematically. The new technics that is filling protective atmosphere in the lower vacuum has been presented firstly. The Yb: YAG laser with a dimension of Φ27mm×100mm was grown by Czochralski method to medium frequency induction heating. The performance of Yb: YAG crystal was investigated by using several measurements, such as absorption spectrum, fluorescence spectrum and so on.

Abstract: In this paper, the threshold voltage of diamond film-based metal-semiconductor field effect transistors (MESFETs) has been simulated using Silvaco TCAD tools. The drain current (Id) versus gate voltage (Vg) relationship, and the distribution of acceptors in diamond surface conduction layer were also investigated. From the simulation results, it was found that the gate length contributed the most to the threshold voltage, while the doping depth almost had no impact on the threshold voltage value.

Abstract: Metal films are deposited on polyimide by pulsed cathode arc. Metal film wrinkles are found by SEM. These wrinkles are caused by film stress which is from inherent defect of film materials. The soft substrate will deform with metal films because there is shear force between metal films and soft substrate surface. The film stress with soft substrate together is discussed in detail.

Abstract: The workability of self-compacting concrete is influenced greatly by aggregate. In this study, the effects of aggregate gradation, maximum particle size, sand percentage and particle shape on the workability of self-consolidating concrete were investigated. The results showed that the compressive strength and workability of self-compacting concrete were increased by increasing the particle size of aggregate, optimizing gradation, choosing proper sand percentage and increasing shape index in a certain range.

Abstract: The N-doped TiO₂ thin films were deposited on medical glass slide by pulsed negative bias arc ion plating. The influence of pulsed negative bias, annealing temperature and time on films properties was investigated. Film structure, surface morphologies and optical properties were measured with XRD, SEM and UV-VIS transmittance spectroscope. Photo-catalytic performance of the films was evaluated by degrading methyl orange. The results show that the absorption edges of the as-deposited films increase with the rising of the pulse negative bias, and the maximum of 550 nm is achieved under -600V bias. The films absorption edges increase in different degree after annealing at 400°Cand 500°Cfor 2h, and the best extending can increase 22nm after annealing. The diffraction peak intensity and surface grain size increase with increasing the annealing temperature and time. The grain size of films after annealing at 400°C for 4h is largest of all the films. The pulsed negative bias and annealing treatment not only indecrease TiO₂ thin films the UV catalytic performance, but also extend the catalytic properties to the sunlight.

Abstract: The imaging resolution of conventional lenses is limited by diffraction. Hyperlens taking a form of metamaterial have the ability to overcome the diffraction barrier. In this paper, the impact of structure parameters of hyperlens including the mental medium parameters ,curvature radius, layer number, and thickness of layer, on sub-diffraction imaging is simulated and analyzed. The results can be used in optimal design of hyperlens and to improve resolution of sub-diffraction imaging.