An effective strategy to significantly boost the capacitive properties of Fe2O3‐based anodes by Ti doping and poly(3,4‐ethylenedioxythiophene) (PEDOT) coating is successfully demonstrated. The Ti‐Fe2O3@PEDOT electrode exhibits a significant capacitance improvement and exceptionally cyclic stability. A remarkable energy density of 0.89 mWh cm−3 can be obtained for a high‐performance asymmetric supercapacitor device consisting of Ti‐Fe2O3@PEDOT and a MnO2 anode.

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Three dimensional graphene-based frameworks (3DGFs) hold great promise for microbial fuel cells (MFCs) due to their macroporous structure, outstanding electrical conductivity, high surface area and prominent biocompatibility.

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Physical laboratory experiments are built to provide students with hands-on opportunities and have long been crucial for engineering training. However, due to the rapid growth in number of enrollments, limited and shared space, undergraduate students have experienced an increasing difficulty gaining valuable hands on experience in the lab. While traditional lab should never be abandoned, adding virtual labs to assist with it could benefit students without the limitation of enrollment capacity or lab availability. In this paper, we discussed a pilot study of developing a virtual fluid mechanics laboratory to supplement existing physical lab exercises. The virtual lab was designed to enrich students’ lab experience, stimulate interests, and bring more individual exercise time. It was developed to contain two components: a virtual lab tour and a virtual reality (VR) simulated pump experiment. The virtual tours served as a pre-lab instruction tool that provided students with an overview of the fluid mechanics lab. The VR pump experiment replicated the physical experience of performing the physical lab. Preliminary feedbacks were positive for both components of the virtual lab. Students considered that the virtual tours were very informative and useful, while that the VR pump lab was intuitive and time-saving. This proved that with realistic lab simulations, the virtual lab had great potential to provide students more flexibility to perform hands-on experiment and to develop technical acumen outside of the physical classroom. Further improvement was discussed to implement in the next stage to create more immersive experience in assistance of the lab instruction.

The development of clean, sustainable alternative energy sources is increasingly important. One promising alternative to depleting fuel reserves is algae‐based biodiesel fuel, which is both non‐toxic and renewable. Despite the tremendous potential of algae‐based biodiesel fuel, it has not yet been profitable because of the high cost per unit area of large cultivation. We present a novel application of Orthogonal Array Composite Designs (OACDs) to optimize lipid production of a cell‐free system for algae. An OACD consists of a two‐level fractional factorial design and a three‐level orthogonal array. We start with an initial screening experiment based on six chemicals using an OACD with 50 runs. Based on this experiment, two chemical compounds were removed and a follow‐up 25‐run OACD with four chemicals was performed. Our analysis shows that only three chemicals – nitrogen, magnesium, and phosphate – are essential for lipid accumulation, and a range of optimum combinations of these three chemicals is identified. The lipid accumulation for these three chemical combinations is substantially higher in comparison to the commercial medium, which contains 16 chemicals and soil water. This leads to a reduced cost of the chemical medium and increased efficiency of biodiesel production from the algal‐based cell‐free system, which can be used to significantly expand the use of biodiesel as a viable alternative to fossil fuels. Copyright © 2015 John Wiley & Sons, Ltd.

Nanoscale radiative thermal transport between a pair of metamaterial gratings is studied within this work. The effective medium theory (EMT), a traditional method to calculate the near-field radiative heat transfer (NFRHT) between nanograting structures, does not account for the surface pattern effects of nanostructures. Here, we introduce the effective approximation NFRHT method that considers the effects of surface patterns on the NFRHT. Meanwhile, we calculate the heat flux between a pair of silica (SiO2) nanogratings with various separation distances, lateral displacements, and grating heights with respect to one another. Numerical calculations show that when compared with the EMT method, here the effective approximation method is more suitable for analyzing the NFRHT between a pair of relatively displaced nanogratings. Furthermore, it is demonstrated that compared with the result based on the EMT method, it is possible to realize an inverse heat flux trend with respect to the nanograting height between nanogratings without modifying the vacuum gap calculated by this effective approximation NFRHT method, which verifies that the NFRHT between the side faces of gratings greatly affects the NFRHT between a pair of nanogratings. By taking advantage of this effective approximation NFRHT method, the NFRHT in complex micro/nano-electromechanical devices can be accurately predicted and analyzed.