Advanced Materials Research Vol. 662

Abstract: The calcination products of Mg/(Al-Fe) hydrotalcite-like compounds (HMAF) were used as adsorbent to remove perchlorate in affected water. HMAF were synthesized by co-precipitation method at a constant pH value, the best calcined temperature is 500°C and the optimal Mg/Al/Fe molar ratio is 3:0.8:0.2 (CHMAF5%). Factors such as adsorbent dose, initial pH, initial perchlorate concentration affecting perchlorate adsorption were studied. Results showed that the best parameters of adsorbent dose, pH and perchlorate concentration are 0.2g, pH 4-10 and 2000µg/l, respectively. The calcination products of HMAF can be a promising adsorbent for perchlorate removal.

Abstract: Several kinds of soft magnetic materials prepared by metal injection molding (MIM), including pure iron, soft magnetic stainless steel, Fe-Si alloy, Fe-Co alloy, Fe-Ni alloy are introduced. The advantages of soft magnetic materials prepared by MIM are exhibited, the research status and development of soft magnetic materials prepared by MIM are reviewed.

Abstract: Large diameter (0.4~0.8mm) fiber termination is widely used in the gum related cares. However, cost-effective shaped fiber is not yet developed for high power (~5W) laser application. In this study, we have demonstrated the feasibility of using two stepping motors with a patented axial movement (0.005mm increments) method. The key parameters are investigated using finite element modeling. The results show that larger fiber diameter with less number of feeding increments can damage the fiber during polishing process.

Abstract: Due to the impact of the CO2 kinetic cooling effect, which is kind of energy transfer between CO2 and N2 molecules, the mixed gas containing CO2, the amplitude of the photoacoustic signal and the detected gas concentration are no longer a linear change, and the signal phase also has been changed. In this study, the energy transfer model between CO2 and N2 molecules in near-infrared band (1～2.2μ) was derived, the influence from CO2 gas with different concentration on photoacoustic signal was discussed, and the relevant experimental tests were made，which showed that the proposed model can scientifically interpret the energy transfer relation between CO2 and N2 molecules and can quantitatively determine the influence from CO2 gas with different concentration on photoacoustic signals excited by mixed gas with including CO2 gas.

Abstract: We investigate the entanglement dynamics in a quantum system consisting of three two-level atoms interacting with three spatially separated cavities with the influence of the Stark shift, and we can find that the entanglement sudden death (ESD) and birth (ESB) will be improved by adjusting the Stark parameters. When we choose the appropriate Stark parameters, the phenomena of ESD and ESB will be appeared, but, which will appear earlier than the other depends on the Stark-shift values.

Abstract: We propose a scheme for the generation of three atom W states via the microtoroidal cavity-atom coupling system. This scheme can also be generalized to multi-atom W states. In this paper, three-atom resonant interact simultaneously with two counterpropagating cavity modes which can be produced by embedding Bragg grating in the microtoroidal. A single resonant interaction is required, thus this scheme is simple. Moreover, the required time to complete the whole process almost unchanges with increasing the number of atoms

Abstract: This paper describes our recent work on the mechanical reliability of a commercial MEMS microphone by performing three mechanical tests, i.e. a constant acceleration test, a mechanical shock test, and a random vibration test, according to the standard of Mil-Std-883. We find that, the studied MEMS part of the microphone can survive a stress limit above 20000g. Two failure modes, i.e. the breaking of diaphragm and the backplate and the delamination of the electrode from the backplate are revealed in the three tests.

Abstract: This paper presents the design of a Film Bulk Acoustic Wave Resonators (FBARs) operating in Ku-band. The one-dimensional (1-D) numerical and the three-dimension (3-D) Finite Element Method (FEM) simulation results are analysed and compared. The results show that coupling coefficient (k²_eff) up to 6.5% can be obtained with optimised thickness ratio of electrode/piezoelectric layers of operating frequencies greater than 15GHz. The FBARs have areas of 1.69x10^-4µm² and 7.84x10^-4µm² for series resonance frequency of 14.7GHz and 15.9GHz respectively and achieves quality (Q) factor of 300. The designed FBAR filter operating in Ku-band has the centre frequency of 15.5 GHz, the insertion loss of 3.5dB, out-of-band rejection of 13dB and fractional bandwidth of 6.6%.

Abstract: As an emerging nanotechnology, quantum-dot cellular automata (QCA) has the potential to be used for next generation VLSI. Various designs of combinational logic circuits have been proposed for QCA implementation, but sequential circuit design is limited due to the lack of high-performance QCA flip-flops. After an introduction on QCA and dual-edge triggered (DET) flip-flops, a new QCA DET T flip-flop following a pulsed latch scheme is presented. The proposed T flip-flop is simulated using QCADesigner simulator and its logic functionality is verified. The same data throughput of the DET flip-flop can be achieved while operating at half the clock frequency of a single-edge triggered (SET) counterpart. The proposed flip-flop is promising in building QCA sequential circuits with low power and high performance.

Abstract: Influence of insulator layer width on propagation properties of symmetric surface plasmon polariton (SPP) mode, which is excited through a dipole embedded in SiO2 layer of Au/SiO2/Au structure in metal-insulator-metal (MIM) waveguide, has been investigated. The symmetric SPP mode has a propagation length along SiO2/Au interface that depends on SiO2 layer width. Its maximal value is 0.61 μm with SiO2 layer width of 100 nm. These values provide a theoretical reference for designing a high-performance SPP source using Au/SiO2/Au structure.