Ionic liquids (ILs) have many attractive properties. For example, their physical and chemical properties can be tuned by a judicious design of the cations and anions, making them ideal candidates for ...designable building blocks of stimuli‐responsive materials. Numerous IL‐based stimuli‐responsive materials have been developed by chemical modification (covalent, coordination, or ionic functionalization) or physical blending of ILs with other functional materials. The flexible tunability of ILs provides a great opportunity to achieve the desired physicochemical properties for task‐specific applications, such as sensing, display, gas capture, and so on. This review aims to address the recent advances in IL‐based stimuli‐responsive materials, which are categorized by the type of external stimuli, including gas‐responsive, organic solvent‐responsive, ion‐responsive, pH‐responsive, thermo‐responsive, photo‐responsive, and electro‐responsive materials.
The attractive properties of ionic liquids make them ideal candidates for designable building blocks of stimuli‐responsive materials. This review aims to address the recent advances in ionic liquid‐based stimuli‐responsive materials and they are categorized by the type of external stimuli, including gas‐responsive, organic solvent‐responsive, ion‐responsive, pH‐responsive, thermo‐responsive, photo‐responsive, and electro‐responsive materials.
Road-railroad crossings are where different modes of transportation meet, which brings safety concerns and the potential for hampering transportation efficiency and creating other issues. By ...surveying and interviewing professionals in Louisiana, this study aims to investigate incentive programs and their effectiveness in reducing the number of at-grade crossings for policy implementation. The results show that most agencies in Louisiana were concerned about safety at railroad crossings with one third supporting closing crossings to alleviate their concerns. In addition, stakeholders were also concerned about the condition and maintenance of crossings, traffic management, and access for active transportation. Among five identified programs, road improvement was ranked as the most effective program, and the combination of multiple programs may be more effective than any individual program. This study recommends that context-sensitive, accessible, and transparent policies, public education, and stakeholder engagement may help to improve safety and efficiency at road-railroad crossings overall.
Professor Shi Zhengyi (1932-2015) was the same age as my father. In Chinese tradition, a teacher for a day is a father for life. Hence, I respectfully call Professor Shi my Father-like Professor. ...Born in Tongcheng County, Anhui Province, in 1932. Professor Shi graduated from the Master’s Program in History of Economics of the Department of Economics of Renmin University of China in 1957. As a renowned Chinese ethnographer and economist, he has been engaged in theoretical research and teaching economics and ethnology for a long time. With meticulous scholarship and profound knowledge, he has studied Chinese and Western cultures with countless new ideas for research. Moreover, he proposed and verified the scientific approach to theoretical thinking that goes from “representation to the abstract and the concrete.” He initiated the establishment of the discipline of ethnological economics and the Institute of Ethnological Economics, pioneering the Marxist theory of ethnology specific to China. He was also the first to systematically verify the develop-the-west strategy, providing a theoretical basis for formulating national policies. He has been devoted to teaching for over 50 years, producing fruitful academic results. He has published eight monographs, edited 14 books, and published more than 120 papers. The Collected Works of Professor Shi, with more than 600,000 characters, represents the crystallization of his academic thoughts throughout his life. In his long-term academic activities and educational practices, Professor Shi developed a unique scientific approach to study known as the “rigorous, diligent, practical, creative and contextual” approach.
It is very important to create novel topologies and improve structural complexity for covalent organic frameworks (COFs) that might lead to unprecedented properties and applications. Despite the ...progress achieved over the past decade, the structural diversity and complexity of COFs are quite limited. In this Communication, we report the construction of COFs bearing three different kinds of pores through the heterostructural mixed linker strategy involving the condensation of a D 2h -symmetric tetraamine and two C 2-symmetric dialdehydes of different lengths. The complicated structures of the triple-pore COFs have been confirmed by powder X-ray diffraction and pore size distribution analyses.
Traditional sound sources and sound detectors are usually independent and discrete in the human hearing range. To minimize the device size and integrate it with wearable electronics, there is an ...urgent requirement of realizing the functional integration of generating and detecting sound in a single device. Here we show an intelligent laser-induced graphene artificial throat, which can not only generate sound but also detect sound in a single device. More importantly, the intelligent artificial throat will significantly assist for the disabled, because the simple throat vibrations such as hum, cough and scream with different intensity or frequency from a mute person can be detected and converted into controllable sounds. Furthermore, the laser-induced graphene artificial throat has the advantage of one-step fabrication, high efficiency, excellent flexibility and low cost, and it will open practical applications in voice control, wearable electronics and many other areas.
We herein report the construction of a new heteropore COF which consists of two different kinds of micropores with unprecedented shapes. It exists as hollow microspheres and exhibits an extremely ...high volatile iodine uptake (up to 481 wt%) by encapsulating iodine in the inner cavities and porous shells of the microspheres.
Vibronic coupling is a central issue in molecular spectroscopy. Here we investigate vibronic coupling within a single pentacene molecule in real space by imaging the spatial distribution of ...single-molecule electroluminescence via highly localized excitation of tunneling electrons in a controlled plasmonic junction. The observed two-spot orientation for certain vibronic-state imaging is found to be evidently different from the purely electronic 0-0 transition, rotated by 90°, which reflects the change in the transition dipole orientation from along the molecular short axis to the long axis. Such a change reveals the occurrence of strong vibronic coupling associated with a large Herzberg-Teller contribution, going beyond the conventional Franck-Condon picture. The emergence of large vibration-induced transition charges oscillating along the long axis is found to originate from the strong dynamic perturbation of the anti-symmetric vibration on those carbon atoms with large transition density populations during electronic transitions.
Here, we review the possible reasons responsible for the occurrence, maintenance and proliferation of antibiotic resistance genes (ARGs) in the environment, as well as the corresponding mechanisms of ...their development, diffusion and transfer. Additionally, elimination strategies are also discussed. The factors that influence the development of ARGs are selection pressure, including that from antibiotics, metal and multiple other factors, co-resistance and cross-resistance, microbial consortium structure, nutrients in the environment and oxidative stress responses. Process parameters, transport pathways, and elimination strategies to reduce the health risk caused by ARGs are also reviewed in detail. Moreover, knowledge gaps and future opportunities of ARGs are addressed.
Interlayer stacking of 2D covalent organic frameworks (COFs) plays a crucial role in determining not only the geometry of channels inside COFs but also the mobility of carrier transport between COF ...layers. However, though topological structures of 2D COFs monolayers can be precisely predicted through the structures of building blocks, factors affecting their interlayer stacking remain poorly understood. In this work, a truxene‐based building block on which six methyl groups are introduced was designed. The condensation of it with 1,4‐diaminobenzene or benzidine afforded 2D COFs with the methyl groups extending out‐of‐plane of the layers. A significant influence of the methyl groups on interlayer stacking of the COFs was revealed by the adoption of inclined packing of monolayers, which has never been experimentally observed before. This unprecedented stacking manner was confirmed by powder X‐ray diffraction analysis, pore‐size distribution analysis, and TEM investigation.
Inclined stacking of covalent organic framework monolayers has been experimentally confirmed for the first time. The unprecedented stacking manner was realized through the condensation of 1,4‐diaminobenzene or benzidine with a truxene‐based building block in which six methyl groups were fixed out‐of‐plane of the truxene core.
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