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As a smart material, photoresponsive liquid-crystalline polymers exhibit interestingly tunable properties from the nanoscale to the macroscale, which are attributed to their combination of liquid crystal ordering and photoswitchable features. An azobenzene-containing liquid-crystalline polymer is a typical representative, which has been studied from many different aspects. However, the lack of research on the structure–performance relationship and multi-scale manipulation has limited its applications in a broader field. Over the past few years, great efforts have been devoted to achieving the control at multiple scales using light, which has promoted their applications in the fields of energy storage, advanced anticounterfeiting and switchable adhesion. Here, we summarize recent progress in photoresponsive liquid-crystalline polymers, including molecular design, fabrication techniques and the manipulation mechanism from the nanoscale to the micrometre scale and then the macroscale. Their various applications based on abundant photoresponsive properties are systematically summarized. Finally, the existing challenges and opportunities in this field are discussed. [ABSTRACT FROM AUTHOR]

Manipulation of periodic micro/nanostructures in polymer film is of great importance for academics and industrial applications in anticounterfeiting. However, with the increasing demand on information security, materials with time‐dependent features are urgently required, especially the material where the same information can appear more than once on the time scale. Here, one concise strategy to realize time‐dependent anticounterfeiting and "double‐lock" information encryption based on a host‐guest system is proposed, with one photoresponsive azopolymer as the host and one liquid‐crystalline molecule as the guest. The system exhibits a tunable mass transport in pre‐designed periodic micro/nanostructures by tailoring the process of cis‐to‐trans recovery of azo groups and assembly of mesogenic trans‐isomers, resulting in a dynamic structural color in film. Taking advantage of this extraordinary feature, time‐dependent dynamic anticounterfeiting has been achieved. More importantly, the time of each state's appearance in the whole process can be modulated by changing the host‐guest ratio. Combining the manipulatable process of mass transport with the unique decoding method, the stored information in film can be decrypted correctly. This work provides an unprecedented dynamic approach for advanced anticounterfeiting technology with a higher level of security and high‐end applications in information encryption. [ABSTRACT FROM AUTHOR]

The vapor-liquid equilibrium (VLE) of CO2 in a reactive solvent is essential for the proper simulation and design of CO2 absorption processes. This work presents a systematic investigation on CO2 absorption in various aqueous monoethanolamine (MEA) solutions. CO2 solubility in MEA was measured at 298, 313, 333, and 353 K with CO2 partial pressure ranging from 34.5 to 78.0 kPa. A modified Kent-Eisenberg model was developed based on the measured solubility data, showing good predictions over the liquid phase speciation for the CO2-H2O-MEA system. We presented a new analysis based on the first-order difference curve of distribution profiles of the species. Based on the main reactions that occurred, the CO2 absorption process was demonstrated to be divided into four regions with increasing CO2 loading from 0 to 1. Accordingly, kinetic study was proposed to be conducted in the first region, whereas measuring of mass transfer in the first three regions. The findings in this work extend the existing knowledge of CO2 absorption process in terms of speciation and can provide important guidance for further study of the process characteristics using aqueous amine absorbents. [ABSTRACT FROM AUTHOR]

Aiming at the problem of the inefficiency of spatio-temporal information in traditional trajectory similarity analysis, combined with the main characteristic of communication transmitter, an algorithm of transmitter trajectory similarity analysis based on spatio-temporal and semantic information is proposed. In this algorithm, the distance measurement of similar motion trajectory is improved, and a trajectory spatio-temporal similarity algorithm based on Mahalanobis distance is proposed, which computes the similarity after trajectory segmentation, overcomes the influence of time mismatch trajectory and different sampling intervals on trajectory similarity judgment. At the same time, combined the semantic similarity data search algorithm based on efficient K-nearest neighbor (KNN) similarity search, accurate judgment of the similar trajectory of the transmitter is realized. The algorithm can judge the similar trajectory accurately, which is superior to the existing similar trajectory judgment methods, and adapts to the noise environment. The simulation experiment results verify the performance of the algorithm. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) material membranes have shown great potential for molecular separation. However, it remains challenging to controllably tune 2D material membrane structures with ordered nanochannels without non-selective defects. Herein, for the first time, 2D Ti2CTx MXene membranes were designed and fabricated for efficient solvent dehydration via a new strategy. Specifically, positively charged hyperbranched polyethylenimine was intercalated between negatively charged MXene nanosheets to assemble regular stacking structures via electrostatic interactions, followed by interfacial polymerization with trimesoyl chloride to seal possible non-selective defects. This strategy realized integrated Ti2CTx membranes as thin as ∼100 nm with highly ordered 2D nanochannels, thereby exhibiting outstanding separation performance: the water content was enriched to ＞99 wt% in permeate from 10 wt% water/isopropanol mixtures. Compared with commonly studied Ti3C2Tx MXene membranes prepared by the same approach, the Ti2CTx membranes showed higher selectivity with similarly high flux. The membrane fabrication approach developed herein offers a powerful platform for the rational design of 2D material thin films for precise molecular separation and other applications. [ABSTRACT FROM AUTHOR]

Thin film composite (TFC) membranes have attracted great research interest for a wide range of separation processes owing to their potential to achieve excellent permeance. However, it still remains challenging to fully exploit the superiority of thin selective layers when mitigating the pore intrusion phenomenon. Herein, a facile and generic interface‐decoration‐layer strategy collaborating with molecular‐scale organic–inorganic hybridization in the selective layer to obtain a high‐performance ultrathin film composite (UTFC) membrane for CO2 capture is reported. The interface‐decoration layer of copper hydroxide nanofibers (CHNs) enables the formation of an ultrathin selective layer (≈100 nm), achieving a 2.5‐fold increase in gas permeance. The organic part in the molecular‐scale hybrid material contributes to facilitating CO2‐selective adsorption while the inorganic part assists in maintaining robust membrane structure, thus remarkably improving the selectivity toward CO2. As a result, the as‐prepared membrane shows a high CO2 permeance of 2860 GPU, superior to state‐of‐the‐art polymer membranes, with a CO2/N2 selectivity of 28.2. The synergistic strategy proposed here can be extended to a wide range of polymers, holding great potential to produce high‐efficiency ultrathin membranes for molecular separation. [ABSTRACT FROM AUTHOR]