Converting excess low-price electricity into high-temperature stored heat for industry and high-value electricity production

The large-scale deployment of wind or solar energy results in electricity prices below the price of fossil fuels at times of high wind or solar output. Price collapse can be limited by using low-price electricity to heat firebrick to high temperatures, store the heat in firebrick, and provide hot air as needed to industrial furnaces, kilns, power plants and gas turbines. This sets a minimum price on electricity near that of fossil fuels.     

Analytical and self-consistent quantum mechanical model for a surrounding gate MOS nanowire operated in JFET mode

We derive an analytical model for the electrostatics and the drive current in a silicon nanowire operating in JFET mode. We show that there exists a range of nanowire radii and doping densities for which the nanowire JFET satisfies reasonable device characteristics. For thin nanowires we have developed a self-consistent quantum mechanical model to obtain the electronic structure.     

Coupling heat storage to nuclear reactors for variable electricity output with baseload reactor operation

Nuclear reactors produce heat and thus can couple to heat storage systems to provide dispacthable electricity while the reactor operates at full power. Six classes of heat storage technologies couple to light-water reactors with steam cycles. Firebrick Resistance-Heated Energy Storage (FIRES) converts low-price electricity into high-temperature stored heat for industry or power. FIRES and brick recuperators coupled to nuclear brayton power cycles may enable high-temperature reactors to buy electricity when prices are low and sell electricity at higher price.     

Microscale Inhomogeneities in Aluminum Solution-Doping of Silica-Based Optical Fibers

The microstructure of aluminum (Al) solution-doped soot layers in modified chemical vapor deposition fabrication of silica-based optical fibers has been studied. It is shown that such Al doping is predominantly determined by deposition temperature. Radial and longitudinal Al doping distributions have been investigated in soot layers, in fully sintered glass layers, and in collapsed preforms. Formation mechanisms are discussed.     

Mechanical properties of continuous bamboo fiber-reinforced biobased polyamide 11 composites

This study is devoted to the analysis of the properties of continuous bamboo fiber (BF)-reinforced polyamide 11 (PA 11) composites. The SEM observations highlighted continuity between BFs and the polymeric matrix showing a high density of hydrogen bonds. The comparative calorimetric study of the matrix and its composites showed that the crystallinity of PA 11 was not modified by the presence of bamboo fibers. The physical aging observed in PA 11 is no more observed in composites due to physical interactions between PA 11 and BFs. The mechanical properties were investigated by tensile strength and dynamic mechanical analysis. The introduction of BFs enhanced Young's modulus of the matrix by a factor of 10. The presence of BFs also improved the storage shear modulus G′ over the whole temperature range. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2019 , 136, 47623.     

Poly(N-isopropylacrylamide)/mesoporous silica thermosensitive composite hydrogels for drug loading and release

Temperature-sensitive hydrogels are attracting increasing attention for controlled drug delivery. However, achieving high drug loadings and sustained drug release remains challenging. Herein, we describe the successful synthesis of a series of novel temperature-sensitive poly(N-isopropylacrylamide) (PNIPA)/mesoporous silica nanoparticles (MSN) hydrogels by physical crosslinking of NIPA with MSN. The external and internal structures, temperature sensitivity, drug-loading capacity, and blood compatibility of the PNIPA/MSN composite hydrogels are studied. Results show that MSN addition improved the network structure and adjusted the size of the hole, MSN could also act as drug carrier, thereby enhancing the drug loading capacity. The composite hydrogels underwent a phase transition at 33.7 °C (at the lower critical solution temperature). The hemolysis rate of the composite hydrogels was less than 1%, thus they can be classified as a nonhemolytic materials with good biocompatibility. The composite hydrogels reported here thus have great potential in drug transport and temperature-activated drug release. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020 , 137, 48391.     

Bubble Formation at a Rotating Cylindrical Surface in Cross‐Flowing Liquid

A novel method of gas sparging from a rotating cylinder is proposed, which prevents against formation of large attached gas cavities in cross‐flowing liquids including those flowing downwards. Experimental and theoretical results regarding critical rotation speed necessary to remove the attached cavity, bubble formation process and size distribution of the produced bubbles in a low viscosity system (air‐water) are presented in this study.     

Knowledge-Assisted Visualization and Segmentation of Geologic Features

The proposed approach employs domain knowledge about the structure and topology of geologic features in seismic data to steer dynamic surfaces into those features. Specialized attributes guide evolving surfaces by adapting to the features' known shape. Geometric, topological, and geologic information can be rendered on the evolving surface, which lets the user infer knowledge during the process. The approach is implemented in a 3D visualization environment. A user study demonstrates this approach's ability to transfer domain knowledge to nonexperts. This article is part of a special issue on knowledge-assisted visualization.