Search

Gyroid, double diamond and the body‐centred "Plumber's nightmare" are the three most common bicontinuous cubic phases in lyotropic liquid crystals and block copolymers. While the first two are also present in solvent‐free thermotropics, the latter had never been found. Containing six‐fold junctions, it was unlikely to form in the more common phases with rod‐like cores normal to the network columns, where a maximum of four branches can join at a junction. The solution has therefore been sought in side‐branched mesogens that lie in axial bundles joined at their ends by flexible "hinges". But for the tightly packed double framework, geometric models predicted that the side‐chains should be very short. The true Plumber's nightmare reported here, using fluorescent dithienofluorenone rod‐like mesogen, has been achieved with, indeed, no side chains at all, but with 6 flexible end‐chains. Such molecules normally form columnar phases, but the key to converting a complex helical column–forming mesogen into a framework‐forming one was the addition of just one methyl group to each pendant chain. A geometry‐based explanation is given. [ABSTRACT FROM AUTHOR]

In order to study the effect of water erosion on the adhesion characteristics of warm-mix crumb rubber-modified asphalt (WCR)-steel slag interface, hot-mix crumb rubber-modified asphalt (HCR) was used as the control group. The WCR-aggregate interface adhesion model was established based on the surface energy test. According to the surface energy theory, the adhesion work of WCR-aggregate can be used to calculate their contact angle. Then, the permeability work and spreading coefficient of asphalt-aggregate were obtained. Three processes of asphalt wetting aggregate (adhesion wetting, immersion wetting, and extended wetting) and the compatibility of asphalt-aggregate were analyzed. The interfacial pull-out test and freeze-thaw splitting test were also used to further analyze the adhesion characteristics and water stability of asphalt-aggregate under the action of hydrothermal coupling. Finally, the low-temperature beam bending test of warm/hot-mix crumb rubber-modified asphalt mixture was carried out to verify the experimental results of adhesion characteristics of the asphalt-aggregate interface. The results show that with the erosion of water, the adhesion and water stability of the WCR-steel slag interface and the low-temperature crack resistance of warm/hot-mix crumb rubber-modified asphalt mixture gradually weaken. At the same time, the higher the water bath temperature, the faster the asphalt film destruction, the positive effect of the warm agents on asphalt-aggregate adhesion was weakened, and the WCR-steel slag interface adhesion characteristics were better. The experimental results of low-temperature performance also verify the accuracy of the adhesion characteristics of the asphalt mixture. Finally, the correlation analysis revealed that there was a strong correlation between mechanical indexes (the pull-out strength P, the residual strength ratio, the pull-out strength loss rate η) and water stability index (the freeze-thaw splitting strength ratio). All of them could characterize the water stability of the asphalt-aggregate well. Furthermore, the correlation between η and TSR was the highest, so it is more reliable for evaluating the water stability and adhesion of asphalt and aggregate. [ABSTRACT FROM AUTHOR]

Wind energy has become an essential part of the energy power source of current power systems since it is eco-friendly and sustainable. To optimize the operations of wind farms with the constraint of satisfying the power demand, it is critical to provide accurate predictions of wind power generated in the future. Although deep learning models have greatly improved prediction accuracy, the overfitting issue limits the application of deep learning models trained under one condition to another. A huge number of data are required to train a new deep learning model for another environment, which is sometimes not practical in some urgent situations with only very little training data on wind power. In this paper, we propose a novel learning method, named metareservoir computing (MRC), to address the above issue, combining reservoir computing and meta-learning. The reservoir computing method improves the computational efficiency of training a deep neural network for time series data. On the other hand, meta-learning is used to improve the initial point and other hyperparameters of reservoir computing. The proposed MRC method is validated using an experimental dataset of wind power compared with the traditional training method. The results show that the MRC method can obtain an accurate predictive model of wind power with only a few shots of data. [ABSTRACT FROM AUTHOR]

Extensive exploration is required to deploy mineralization as a tool to develop low-cost yet efficient sustained drug release systems. Unlike previous studies which directly incorporated drug components in mineralized products, we propose an emerging approach to synthesizing drug-loaded CaCO3 composites, relying on the synergistic occlusion of the molecular solutions comprising both the alginate hydrogel matrices and the associated drug (doxorubicin) in the course of mineralization. Independent tools including a scanning electron microscope and adsorption isotherm were employed to characterize the lyophilized composites, which led to the conclusion that the anticancer drug doxorubicin (DOX) was uniformly dispersed in the hydrogel matrices as a molecular solution. The occlusion strategy led to CaCO3-based composites with high loads and sustained and pH-responsive release of DOX. Considering many drug molecules can form molecular solutions with polymeric components, we find that the synergistic occlusion can become a general approach to designing smart drug delivery systems. [ABSTRACT FROM AUTHOR]

Gyroid‐nanostructured all‐solid polymer films with exceedingly high proton conductivity and low H2 gas permeability have been created via crosslinking polymerization of mixtures of a zwitterionic amphiphilic monomer and a polymerizable imide‐type acid that co‐organize into bicontinuous cubic liquid‐crystalline phases. The gyroid nanostructures are visualized by reconstructing a 3D electron map from the synchrotron X‐ray diffraction patterns. These films exhibit high proton conductivity of the order of 10−1 S cm−1 and extremely low H2 gas permeability of the order of 10−15 mol m m−2 s−1 Pa−1. These properties can be ascribed to the presence of the ionic liquid‐like layer along the gyroid minimal surface. Since these two characteristics are required for improving the performance of proton‐exchange membrane fuel cells, the present membrane design represents a promising strategy for the development of advanced devices, pertinent to establishing sustainable energy sources. [ABSTRACT FROM AUTHOR]