A novel Mg-8Al-2Sn-1Zn alloy with a bimodal structure prepared by hard-pate-rolling (HPR) exhibits both higher tensile strength and ductility than its fine-grained counterparts prepared by ...conventional rolling. By delicate electron back-scatter diffraction (EBSD) analysis, we found fine grains with weak basal texture is beneficial for basal slip and favors initial deformation. Meanwhile, coarse grains with a strong basal texture could accommodate abundant newly generated dislocations, promoting work hardening after fine grains are saturated with dislocations. For the first time, individual roles of fine and coarse grains and their synergy effect on enhancing ductility in bimodal structured Mg alloys is clarified.
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•A bimodal grain-structured Mg alloy is fabricated by hard-pate-rolling.•The bimodal sample has higher strength and ductility than fine-grained samples.•The synergy effect of fine and coarse grains on enhancing ductility is clarified.
Nonfullerene acceptors (MQ3, MQ5, MQ6) are synthesized using asymmetric and symmetric ladder‐type heteroheptacene cores with selenophene heterocycles. Although MQ3 and MQ5 are constructed with the ...same number of selenophene heterocycles, the heteroheptacene core of MQ5 is end‐capped with selenophene rings while that of MQ3 is flanked with thiophene rings. With the enhanced noncovalent interaction of O⋅⋅⋅Se compared to that of O⋅⋅⋅S, MQ5 shows a bathochromically shifted absorption band and greatly improved carrier transport, leading to a higher power conversion efficiency (PCE) of 15.64 % compared to MQ3, which shows a PCE of 13.51 %. Based on the asymmetric heteroheptacene core, MQ6 shows an improved carrier transport induced by the reduced π–π stacking distance, related with the increased dipole moment in comparison with the nonfullerene acceptors based on symmetric cores. MQ6 exhibits a PCE of 16.39 % with a VOC of 0.88 V, a FF of 75.66 %, and a JSC of 24.62 mA cm−2.
Selenophene end‐capped asymmetric heteroheptacene core is used to construct an efficient nonfullerene acceptor (MQ6) which shows increased carrier transport due to the enhanced O⋅⋅⋅Se intramolecular noncovalent interaction as well as the increased dipole moment. MQ6 exhibits an outstanding efficiency of 16.39 % when blended with a wide band gap copolymer.
Side‐chain tailoring is a promising method to optimize the performance of organic solar cells (OSCs). However, asymmetric alkyl chain‐based small molecular acceptors (SMAs) are still difficult to ...afford. Herein, we adopted a novel asymmetric n‐nonyl/undecyl substitution strategy and synthesized two A‐D1A′D2‐A double asymmetric isomeric SMAs with asymmetric selenophene‐based central core for OSCs. Crystallographic analysis indicates that AYT9Se11‐Cl forms a more compact and order intermolecular packing compared to AYT11Se9‐Cl, which contributed to higher electron mobility in neat AYT9Se11‐Cl film. Moreover, the PM6 : AYT9Se11‐Cl blend film shows a better morphology with appropriate phase separation and distinct face‐on orientation than PM6 : AYT11Se9‐Cl. The OSCs with PM6 : AYT9Se11‐Cl obtain a superior PCE of 18.12 % compared to PM6 : AYT11Se9‐Cl (17.52 %), which is the best efficiency for the selenium‐incorporated SMAs in binary BHJ OSCs. Our findings elucidate that the promising double asymmetric strategy with isomeric alkyl chains precisely modulates the crystal packing and enhances the photovoltaic efficiency of selenophene‐incorporated SMAs.
Two isomeric A‐D1A′D2‐A type double asymmetric selenophene‐based small molecule acceptors (SMAs) were synthesized by a n‐nonyl/undecyl regioisomeric strategy to optimize single‐crystal packing, improve film morphology, and boost device performance. PM6 : AYT9Se11‐Cl achieved a superior PCE of 18.12 % compared to PM6 : AYT11Se9‐Cl.
A dissymmetric backbone and selenophene substitution on the central core was used for the synthesis of symmetric or dissymmetric A‐DA′D‐A type non‐fullerene small molecular acceptors (NF‐SMAs) with ...different numbers of selenophene. From S‐YSS‐Cl to A‐WSSe‐Cl and to S‐WSeSe‐Cl, a gradually red‐shifted absorption and a gradually larger electron mobility and crystallinity in neat thin film was observed. A‐WSSe‐Cl and S‐WSeSe‐Cl exhibit stronger and tighter intermolecular π–π stacking interactions, extra S⋅⋅⋅N non‐covalent intermolecular interactions from central benzothiadiazole, better ordered 3D interpenetrating charge‐transfer networks in comparison with thiophene‐based S‐YSS‐Cl. The dissymmetric A‐WSSe‐Cl‐based device has a PCE of 17.51 %, which is the highest value for selenophene‐based NF‐SMAs in binary polymer solar cells. The combination of dissymmetric core and precise replacement of selenophene on the central core is effective to improve Jsc and FF without sacrificing Voc.
A dissymmetric backbone and selenophene substitution on the central core was employed to synthesize dissymmetric A‐DA′D‐A NF‐SMAs. Their detailed single‐crystal packing were revealed successfully. The dissymmetric A‐WSSe‐Cl:PM6 device presented an impressive PCE of 17.51 %, which is the highest values for selenophene‐based and the dissymmetric NF‐SMAs in binary PSCs.
Metal–organic frameworks (MOFs), a new class of crystalline molecular solids built from linking organic ligands with metal or metal-cluster connecting points, have recently emerged as a versatile ...platform for developing single-site solid catalysts. MOFs have been used to drive a range of reactions, including Lewis acid/base catalyzed reactions, redox reactions, asymmetric reactions, and photocatalysis. MOF catalysts are easily separated from the reaction mixtures for reuse, and yet their molecular nature introduces unprecedented chemical diversity and tunability to drive a large scope of catalytic reactions. This Perspective aims to summarize recent progress on light harvesting and photocatalysis with MOFs. The charge-separated excited states of the chromophoric building blocks created upon photon excitation can migrate over long distances to be harvested as redox equivalents at the MOF/liquid interfaces via electron transfer reactions or can directly activate the substrates that have diffused into the MOF channels for photocatalytic reactions. MOF-catalyzed and photodriven proton reduction, CO2 reduction, and organic transformations will be discussed in this Perspective.
Mitochondrial damage is a critical contributor to cardiac ischemia/reperfusion (I/R) injury. Mitochondrial quality control (MQC) mechanisms, a series of adaptive responses that preserve mitochondrial ...structure and function, ensure cardiomyocyte survival and cardiac function after I/R injury. MQC includes mitochondrial fission, mitochondrial fusion, mitophagy and mitochondria-dependent cell death. The interplay among these responses is linked to pathological changes such as redox imbalance, calcium overload, energy metabolism disorder, signal transduction arrest, the mitochondrial unfolded protein response and endoplasmic reticulum stress. Excessive mitochondrial fission is an early marker of mitochondrial damage and cardiomyocyte death. Reduced mitochondrial fusion has been observed in stressed cardiomyocytes and correlates with mitochondrial dysfunction and cardiac depression. Mitophagy allows autophagosomes to selectively degrade poorly structured mitochondria, thus maintaining mitochondrial network fitness. Nevertheless, abnormal mitophagy is maladaptive and has been linked to cell death. Although mitochondria serve as the fuel source of the heart by continuously producing adenosine triphosphate, they also stimulate cardiomyocyte death by inducing apoptosis or necroptosis in the reperfused myocardium. Therefore, defects in MQC may determine the fate of cardiomyocytes. In this review, we summarize the regulatory mechanisms and pathological effects of MQC in myocardial I/R injury, highlighting potential targets for the clinical management of reperfusion.
Mitochondrial quality control contributes to acute cardiac I/R injury. The mitochondrial network is constantly reshaped by the antagonistic activities between mitochondrial fission and fusion. Mitophagy allows autophagosomes to selectively degrade damaged mitochondria. When these adaptive responses fail, programmed cell death by apoptosis or necroptosis is activated. Display omitted
An ideal cancer treatment should not only destroy primary tumors but also improve the immunogenicity of the tumor microenvironment to achieve a satisfactory anti‐tumor immune effect. We designed a ...carbonic anhydrase IX (CAIX)‐anchored rhenium(I) photosensitizer, named CA‐Re, that not only performs type‐I and type‐II photodynamic therapy (PDT) with high efficiency under hypoxia (nanomolar‐level phototoxicity), but also evokes gasdermin D (GSDMD) mediated pyroptotic cell death to effectively stimulate tumor immunogenicity. CA‐Re could disrupt and self‐report the loss of membrane integrity simultaneously. This promoted the maturation and antigen‐presenting ability of dendritic cells (DCs), and fully activated T cells dependent adaptive immune response in vivo, eventually eliminating distant tumors at the same time as destroying primary tumors. To the best of our knowledge, CA‐Re is the first metal complex‐based pyroptosis inducer.
A carbonic anhydrase IX (CAIX)‐anchored photosensitizer CA‐Re was developed. It is capable of inducing and self‐reporting membrane rupture upon irradiation, as well as evoking pyroptosis to activate anti‐tumor immunity.
DC microgrids consist of multiple power electronic converter units interconnected in a network with sources and loads. They are commonly found in the power systems of electric ships, aircrafts, etc. ...The main focus of this paper is to study the stability of power converters-based dc microgrids. These high switching frequency electronics are controlled in a way as to maintain constant voltage, current, or power to the load. Due to their high bandwidth, they can be simplified as a constant power load. For this reason, a nonlinear system arises where it is no longer satisfactory to assume local stability. Methods presented in the literature will be reviewed and a method based on semidefinite programming (SDP) will be developed to simplify the stability analysis of these dc microgrids. Furthermore, a robust controller approach based on a similar SDP technique is proposed in order to guarantee and expand the stability region using energy storage.
The fabrication of nanowire (NW)‐based flexible electronics including wearable energy storage devices, flexible displays, electrical sensors, and health monitors has received great attention both in ...fundamental research and market requirements in our daily lives. Other than a disordered state after synthesis, NWs with designed and hierarchical structures would not only optimize the intrinsic performance, but also create new physical and chemical properties, and integration of individual NWs into well‐defined structures over large areas is one of the most promising strategies to optimize the performance of NW‐based flexible electronics. Here, the recent developments and achievements made in the field of flexible electronics composed of integrated NW structures are presented. The different assembly strategies for the construction of 1D, 2D, and 3D NW assemblies, especially the NW coassembly process for 2D NW assemblies, are comprehensively discussed. The improvements of different NW assemblies on flexible electronics structure and performance are described in detail to elucidate the advantages of well‐defined NW assemblies. Finally, a short summary and outlook for future challenges and perspectives in this field are presented.
Directional assembly of nanowires into 1D, 2D, and 3D assemblies toward flexible electronic devices benefits many potential applications. 1D assemblies with fiber structures can be used as flexible electronics for textiles, 2D assemblies can be used as transparent electrodes or units for logic circuits, and 3D assemblies can be used in the fabrication of pressure sensors or high‐performance energy‐storage devices.
•A roadmap of statistical process monitoring (SPM) is proposed and most recent developments are reviewed and summarized.•Challenges and potential solutions to manufacturing big data are discussed and ...feature based SPM is suggested as promising.•The future directions of SPM and advantages of feature based SPM are discussed in the context of smart manufacturing.
With ever-accelerating advancement of information, communication, sensing and characterization technologies, such as industrial Internet of Things (IoT) and high-throughput instruments, it is expected that the data generated from manufacturing will grow exponentially, generating so called ‘big data’. One of the focuses of smart manufacturing is to create manufacturing intelligence from real-time data to support accurate and timely decision-making. Therefore, big data analytics is expected to contribute significantly to the advancement of smart manufacturing. In this work, a roadmap of statistical process monitoring (SPM) is presented. Most recent developments in SPM are briefly reviewed and summarized. Specific challenges and potential solutions in handling manufacturing big data are discussed. We suggest that process characteristics or feature based SPM, instead of process variable based SPM, is a promising route for next generation SPM and could play a significant role in smart manufacturing. The advantages of feature based SPM are discussed to support the suggestion and future directions in SPM are discussed in the context of smart manufacturing.
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