Advanced Materials Research Vols. 512-515

Abstract: custom contoured cushion, pressure ulcer prevention, pressure distribution, CAD/CAM Abstract. In the rehabilitation engineering area, the pressure ulcer prevention is an important and healthy problem, especially for people with the spinal cord injured (SCI). This paper aim to develop a computer aided design and computer aided manufacture (CAD/CAM) method to manufacture custom cushions to prevent pressure ulcer. A pressure sensor mat is placed between the body and flat polyurethane (PU) foam to measure the pressure distribution at the buttock-cushion interface. Based on the load-deformation characteristics of the foam material, this pressure distribution is converted into the corresponding deformation contour of the foam. Finally, the deformation data was processed and edited using Rhino 3D surface modelling software to create the CAD model of the custom contoured cushion. Then, the CAD data are transferred into CNC milling machine to manufacture the custom contoured cushion.

Abstract: Li₄Ti₅O₁₂ anode materials have been synthesized via mechnochemical method and subsequent sintering with nanosized TiO₂ and Li₂CO₃ as reagents. XRD measurements indicated that well crystallized Li₄Ti₅O₁₂ could be obtained above 800 °C. The sizes of Li₄Ti₅O₁₂ particles increased with sintered temperature augmenting. Various particle distribution and particle sizes are presented in SEM images. In electrochemical investigations, Li₄Ti₅O₁₂ sintered at 800 °C presented excellent discharge-charge performances and rate capability. The discharge capacity could achieve 168 mAh/g and 140 mAh/g at 0.1 C and 1.0 C rate, respectively, which was attributed to its uniform particle size distribution and relatively small particle size.

Abstract: The behavior of a center-cracked aluminum plate repaired with carbon-fiber wrapped composite material under axial loading is investigated. The carbon-fiber wrapped composite material is simulated as transversely isotropic material by means of an equivalent modulus method. The repair patch is applied on one side of the cracked plate. The stress intensity factors along the crack front and the stress distribution at the repair domain are examined. The numerical simulation results indicate that the carbon-fiber wrapped composite material performs very well in the repair to cracked plate and an appropriate thickness of the repair patch needs to be selected.

Abstract: Thin films of RE_0.5Sr_0.5CoO_3-δ (RE=La, Pr, Nd) nominal composition were grown on yttria-stabilized zirconia (YSZ) single crystal substrates by ion-beam sputtering deposition method. The X-ray diffraction spectra and X-ray photoelectron spectroscopy were measured for RE_0.5Sr_0.5CoO_3-δ thin films with perovskite structure. The experimental results indicate that the average grain size of RE_0.5Sr_0.5CoO_3-δ thin films ranges from 86 to 165 nm，and the film obtained by heat-treating at 750 °C is highly oriented . The RE_0.5Sr_0.5CoO_3-δ thin films being mixed-valent systems contains Co³⁺ and Co⁴⁺ ions. There is oxygen vacancy at an interface region for RE_0.5Sr_0.5CoO_3-δ thin films.

Abstract: The axle assembly of fire robot need endure both heavy load and high impact force, and the pitting corrosion in the bearing race become a commom fault. In this paper, the vibration of bearing both in the inner ring and outer ring was analyzed, the characteristics of bearing with pitting corrosion were also analyzed, and based on those characteristics a new method for pitting corrosion diagnosis were proposed, in this method the power cepstrum in the axial direction and histogram of the vibration amplitude in the radial direction were used for detecting the pitting corrosion of bearing, and experiments results proved the practicability and effectiveness of this method.

Abstract: In this paper, p-n coupled photocatalyst CoO/CdS/TiO₂ was prepared by method of impregnation. The structure and optical properties of CdS/TiO2 and CoO/CdS/TiO₂ were characterized by XRD, SEM, BET and UV–vis DRS. The photocatalytic activities of the photocatalysts were evaluated by photocatalytic degradation of methyl orange, and the effect of photocorrosion of CdS in CoO/CdS/TiO₂ was investigated by analyzing the cadmium concentration in the supernate collected after photocatalytic reactions. The results showed that p-n coupled photocatalyst CoO/CdS/TiO₂ not only showed higher efficiency in degradation of methyl orange than CdS/TiO₂, but also exhibited resistance against cadmium leakage under light irradiation. The mechanism of the photocorrosion-delaying by p–n junction was also discussed.

Abstract: In order to reduce the oxidizing and volatilizing caused by Mg element in the traditional methods for synthesizing Mg₂Si compounds, solid state phase reaction at low temperature was introduced by microwave field. XRD was used to characterize the powders. At the same time, the influences of parameters during the synthesis processing were discussed. The results suggest that the heating profile is also dependent on the initial green density and higher green density provides lower heating rate while power setting are fixed and the oxidation of Mg can be rest rained by changing microwave heating programs. It was found that high purity Mg₂Si intermetallic compound can be obtained with excessive content of 8at% Mg from the stoichiometric Mg₂Si, 853K and 30min

Abstract: Conduct test of 2CaO•Al₂O₃•SiO₂ transformed into Q-phase mineral with analytical reagent CaO, SiO₂, Al₂O₃ and MgO in library high-temperature furnace. And carry out experimental investigation on the mineral formation rule of co-generation Q-phase cement clinker on two-section multiphase reaction test stand simulating pulverized coal combustion boiler based on the test. It was found that: 2CaO•Al₂O₃•SiO₂ may generate Q-phase mineral with hydration activity together with appreciated amount of CaO and MgO; experimental coal sort in reasonable ratio may co-generate cement clinker with main mineral sort of 2CaO•SiO₂ and Q-phase mineral. Thermodynamic analysis on mineral formation reaction shows that, in Yanzhou coal co-generating Q-phase cement clinker, the most probably occurring is the direct synthesis reaction of 2CaO•Al₂O₃•SiO₂, followed by 2CaO•SiO₂ direct synthesis reaction and the Q-phase indirect synthesis reaction comes last according to chemical composition of clinkers.

Abstract: CdS/TiO₂ composite films with different Cd:Ti atomic ratio were prepared by a new straightforward particulate layer-by-layer method. Titanium dihydroxide and thiourea were used as precursors. Raman and X-ray photoelectron spectroscopy analysis for the composite films revealed that the TiO₂ formed from titanium precursor retarded the crystal growth of CdS. Luminescence and UV–vis absorption spectra investigation showed that emission and absorption band of CdS/TiO₂ blue shifted as crystal size of CdS decreased. Furthermore, hydrogen formation curves revealed that hydroxyl of CdS/TiO₂ films plays an important role in water splitting reaction under both UV and visible light irradiations.

Abstract: The process conditions of immobilizing penicillin G acylase(PGA) by epoxy resin were studied. This experiment used the Box-Behnken experimental design and response surface methodology(RSM) to optimize the conditions of immobilizing PGA by epoxy resin. The results showed the best process conditions were pH 8.1, temperature 29°C, carrier of epoxy resin 1g and reaction time 24 h. On these conditions, the activity of the immobilized enzyme was 365.76 U g^-1, activity recovery rate was 62.82%. The characteristics of the immobilized PGA under optimal conditions had been measured and found that the optimum pH of immobilized enzyme was 9.0, the optimum temperature was 60°C. It has better continuous operation stability.