Advanced Materials Research Vols. 230-232

Abstract: Batch experiments were carried out to determine the capacity of Bacillus cereus biomass to adsorb Co(II) ions from aqueous solution with respect to pH, initial Co(II) concentration, contact time and biomass dose. The experimental data were modeled by Langmuir and Freundlich isotherm models. Langmuir model resulted in the best fit of the adsorption data. The maximum adsorption capacity for Co(II) was 68.10 mg/g. The best correlation was provided by the second-order kinetic model. The practical implication of this study is the development of an effective and economic technology for Co(II) removal from contaminated waters.

Abstract: A porous carbon was prepared by template method using a mazzite mineral as a template. X-ray diffraction (XRD), nitrogen adsoption, scanning electric microscope (SEM) and cyclic voltammetry (CV) were used to investigate the phase composition, pore structure, morphology and electrochemical performance of the carbon. The surface area of the carbon is 511m²/g. The pores of the carbon are mcropores and mesopores. In H₂SO₄ medium, the carbon exhibits a low capacity and a rectangle-like shaped CV curve at low scan rate. When the scan rate increases from 10 to 200mV/s, the capacity decreases only from 47 to 41F/g, and the rectangle-like shape keeps well. The carbon exhibits an excellent rate capability.

Abstract: The modification of sodium trititanate whisker surface was performed by means of impregnation procedure to fabricate the modified sodium trititanate whisker, which was characterized by infrared spectroscopy(IR). Its adsorptive performance for Cd(II) in a static system was investigated by inductively coupled plasma atomic emission spectrometry(FAAS). The main factors affecting adsorption and desorption of Cd(II), the adsorptive capacity of Cd(II) in optimal condition and adsorption isotherm and the influence of coexistent ions were examined. The adsorptive rate for Cd(II) on 0.2500 g of modified sodium trititanate whisker at PH 5.0 was the best. Cd(II) adsorbed on the modified sodium tretitanate whisker could be eluted with 10 mL of 2.0 mol/L HCl. The adsorptive performance of modified sodium trititanate whisker was better than that of unmodified sodium trititanate whisker.

Abstract: Piezoelectric material shunted with negative capacitance can be used to insulate sound theoretically. But sound insulation of the system is limited by many factors. The dielectric and mechanical loss of the piezoelectric system deteriorate seriously the ability at some frequencies. According to the ideal electric elements formulas, the capacitance has imaginary part because of the loss. It has important influence on sound insulation ability. If a series resistance is introduced into the shunting circuit to form the imaginary part to compensate the loss, it is dependent on frequency. Sound insulation would be increased only in narrow band, and at some frequencies the system with the shunting circuit even becomes unstable.

Abstract: Predicting thermoelastic damping is crucial for the design of high Q MEMS devices. In the past, for the thermoelastic damping in microbeam resonators, Zener’s model (1937 Physical Review 52 230-5; 1938 Physical Review 53 90-9) and Lifshitz and Roukes’ model (2000 Physical Review B 61 5600-9) can give a reasonable prediction. However, the derivations of Zener’s model and Lifshitz and Roukes’ model are only suitable for a simple beam with no proof mass. The microbeam with a proof mass is a common element in many MEMS devices. In this paper, a general proof is presented that shows LR’s model is also valid for the TED in the microbeams with a proof mass. The derivation in this paper is based on a general case.

Abstract: In order to measure the initial gap between the workpiece and tool-cathode in electrochemical machining, the measurement method based on machine vision was studied in this paper. First, the measurement system based on machine vision was established. The hardware of the system consisted of CCD camera, image data acquisition card, light source and computer. The software of the system was developed by VC++6.0. Then, the original digital image of electrochemical machining initial gap collected by the CCD camera system was changed into the contour of image through graying, bivalency, edge detection and segmentation. Through system calibration, the physical size of the gap was calculated. Finally, relative experiments were carried out. The experimental results validated the feasibility of the method which measures the electrochemical machining initial gap based on machine vision.

Abstract: This design is an open-loop aviation electronic equipment rack based on ARINC600 for a aircraft under only air exhaust condition. Conduct tress and stiffness analysis via ANSYS calculating the maximum stress and the maximum distortion. Calculate the maximum power of electronic equipment suitable for this equipment suitable for this equipment rack through heat transfer theory and provide theory basis for electronic equipment layout on the overall aircraft.

Abstract: In this paper, the development of green compact of ZK60 magnesium alloy was studied in the context of MIM using screw type injection moulding machine model Battenfeld BA250CDC. The MIM feedstock used was 64 vol.% powder loading and the balance was palm stearin and low linear density polyethylene with the fraction of 60/40 by weight percent. The injection moulding parameters were then adjusted until the optimal condition of green part was accomplished. Results indicate that the feedstock exhibited good workability when injection moulded at the temperature of 190°C, injection pressure of 900kN, flow rate of 15,5cm³/s and with a very low ejection parameters. This technique provides an additional means to manufacture magnesium alloy components for a wide variety of applications.

Abstract: Data was obtained through scanning manikin and coats separated by using [TC]² 3D body scanner. The method, using [TC]² scanner as the experimental method and through double converting the scanned data format to get torso geometric section sets, was analyzed. Main program source code of Torso was provided in this paper. Geometric algorithms of point cloud data and curve data in there sections was provided based on the interception ways of horizontal sections, vertical sections and other random oblique sections toward torso geometric cross section.

Abstract: According to roller profile modification method, several commonly used modified rollers were selected into the bearing dynamic analysis combined with dynamic model of bearing. As the three types of modified roller an example, simulation program was established to analyze the load distribution of loaded roller under the working conditions of upright loading and offset loading of bearing, respectively. The effects of modified roller on bearing dynamic parameters were discussed. The results provided optimal direction for bearing selection and design under different working conditions.