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A shear-enhanced method based on strong homogenization was proposed and applied in the goethite process for iron removal from the zinc process solution to overcome the low reaction efficiency and the difficulty in residue filtration. A 3D shear-enhanced rector model was designed, and the process was simulated to reveal the characteristics of fluid flow, gas mass transfer, and goethite particle movement under the coupling multi-physical field at different shearing speeds. The results showed that the homogenization of the solution in the reactor is improved by increasing the flow rate of fluids. The gas dispersion is strengthened to increase the mass transfer rate, further accelerating the iron removal reaction. In addition, after iron precipitation, the formed goethite particles and grains can be broken and refined at a high shearing speed. Zinc in the iron precipitation residue is present in adsorption instead of incorporation, indicating fewer zinc losses. Finally, the reliability of the model was verified by experiments. The shear-enhanced goethite process was suggested to improve iron removal efficiency, and it obtains the iron precipitation residue with the crystal structure of α-FeOOH, suggesting further good filtration performance in the following solid/liquid separation stages. [ABSTRACT FROM AUTHOR]

Rescue is a tough and time-consuming task in huge disaster. After stricken by a catastrophic natural disaster, the rescue force is typically deployed under the circumstance of traffic paralysis and lack of supplies. To cope with this situation, plenty of human resource and professional equipment are required. However, both the human resource and equipment are insufficient in most situations. The rescue force needs an efficient technology for searching the survivals, such as the life detection, which can be a key factor in disaster relief. Fast and accurate locating of the survivals will guide the limited rescue resource to save more survivors. However, current life detection technology cannot meet the demand of rescue in huge disaster. A novel life detection system based on fake base station is proposed. The detection system can scan the whole disaster area and find the cell phones, which leads to the surviving owners. As the system works in different way with other traditional human localization technology, a novel RSS/AOA hybrid positioning algorithm was proposed in this paper to increase the accuracy of localization. To verify the accuracy, two simulation tests were designed. The result of the two tests illustrates that the novel algorithm is more suitable to work with the novel life detection system. [ABSTRACT FROM AUTHOR]

In disaster relief, especially in the rescue of serious disaster like great earthquake or tsunami, detecting the exact location of survivors via portable devices can greatly improve the efficiency of search and rescue work. A novel infrastructure-free cell phone positioning system based on software-defined radio, virtual base transceiver station software and its running scheme is proposed in this paper. The identification information of cell phones, receive signal strength and signal transceiver power data can be collected by this system. By using customized antennas with new positioning method, the proposed system can indicate the location of survivals trapped under debris without any operation on cell phones by survivors. With the new hybrid algorithm, search radius of the system can reach more than 1.2 km. And it is also able to implement accurate positioning by this system at the same time. Experimental results demonstrated that the system has significantly improved performance over the traditional methods. [ABSTRACT FROM AUTHOR]

This paper investigates the enhancement of convective heat transfer within a sub-millimetre diameter copper tube using AlO, CoO and CuO microparticle suspensions. Experiments are conducted at different particle concentrations of 1.0, 2.0 and 5.0 wt% and at various flow rates ranging from 250 to 1000 µl/min. Both experimental measurements and numerical analyses are employed to obtain the convective heat transfer coefficient. The results indicate a significant enhancement in convective heat transfer coefficient due to the implementation of microparticle suspensions. For the case of AlO microparticle suspension with 5.0 wt% concentration, a 20.3 % enhancement in convective heat transfer coefficient is obtained over deionised water. This is comparable to the case of AlO nanofluid at the same concentration. Hence, there is a potential for the microparticle suspensions to be used for cooling of compact integrated systems. [ABSTRACT FROM AUTHOR]

This work investigates particle focusing under Dean-flow-coupled elasto-inertial effects in symmetric serpentine microchannels. A small amount of polymers were added to the sample solution to tune the fluid elasticity, and allow particles to migrate laterally and reach their equilibriums at the centerline of a symmetric serpentine channel under the synthesis effect of elastic, inertial and Dean-flow forces. First, the effects of the flow rates on particle focusing in viscoelastic fluid in serpentine channels were investigated. Then, comparisons with particle focusing in the Newtonian fluid in the serpentine channel and in the viscoelastic fluid in the straight channel were conducted. The elastic effect and the serpentine channel structure could accelerate the particle focusing as well as reduce the channel length. This focusing technique has the potential as a pre-ordering unit in flow cytometry for cell counting, sorting, and analysis. Moreover, focusing behaviour of Jurkat cells in the viscoelastic fluid in this serpentine channel was studied. Finally, the cell viability in the culture medium containing a dissolved polymer and after processing through the serpentine channel was tested. The polymer within this viscoelastic fluid has a negligible effect on cell viability. [ABSTRACT FROM AUTHOR]