The urgent need for ecofriendly, stable, long‐lifetime power sources is driving the booming market for miniaturized and integrated electronics, including wearable and medical implantable devices. ...Flexible thermoelectric materials and devices are receiving increasing attention, due to their capability to convert heat into electricity directly by conformably attaching them onto heat sources. Polymer‐based flexible thermoelectric materials are particularly fascinating because of their intrinsic flexibility, affordability, and low toxicity. There are other promising alternatives including inorganic‐based flexible thermoelectrics that have high energy‐conversion efficiency, large power output, and stability at relatively high temperature. Herein, the state‐of‐the‐art in the development of flexible thermoelectric materials and devices is summarized, including exploring the fundamentals behind the performance of flexible thermoelectric materials and devices by relating materials chemistry and physics to properties. By taking insights from carrier and phonon transport, the limitations of high‐performance flexible thermoelectric materials and the underlying mechanisms associated with each optimization strategy are highlighted. Finally, the remaining challenges in flexible thermoelectric materials are discussed in conclusion, and suggestions and a framework to guide future development are provided, which may pave the way for a bright future for flexible thermoelectric devices in the energy market.
A comprehensive exploration of the material design strategies, processing methods, and underlying physics and chemistry behind the enhanced thermoelectric properties of flexible thermoelectric materials is presented, emphasizing innovative approaches and suggesting future pathways for the development of a new generation of wearable electronics.
The long-standing popularity of thermoelectric materials has contributed to the creation of various thermoelectric devices and stimulated the development of strategies to improve their thermoelectric ...performance. In this review, we aim to comprehensively summarize the state-of-the-art strategies for the realization of high-performance thermoelectric materials and devices by establishing the links between synthesis, structural characteristics, properties, underlying chemistry and physics, including structural design (point defects, dislocations, interfaces, inclusions, and pores), multidimensional design (quantum dots/wires, nanoparticles, nanowires, nano- or microbelts, few-layered nanosheets, nano- or microplates, thin films, single crystals, and polycrystalline bulks), and advanced device design (thermoelectric modules, miniature generators and coolers, and flexible thermoelectric generators). The outline of each strategy starts with a concise presentation of their fundamentals and carefully selected examples. In the end, we point out the controversies, challenges, and outlooks toward the future development of thermoelectric materials and devices. Overall, this review will serve to help materials scientists, chemists, and physicists, particularly students and young researchers, in selecting suitable strategies for the improvement of thermoelectrics and potentially other relevant energy conversion technologies.
There has been much interest in link prediction research with significant studies on how to predict missing links or future links in a network based on observed information. However, the key solution ...to tackle the link prediction problem is how to measure the similarity between the nodes in a network with higher accuracy. Several techniques have been proposed that utilize the similarity between nodes to estimate their proximity in the network. In this paper, an efficient link prediction algorithm that predicts relationships between links using the network structure is proposed. This algorithm uses common neighbors in addition to the degree distribution of the nodes to estimate the possibility of the presence of a link between two nodes in a network based on local information. Extensive experiments are carried out and compared with 12 standard similarity‐based methods using seven real‐world datasets. The experimental results show that our method has higher prediction accuracy compared with most of the local information based methods like the Common Neighbor and Preferential Attachment. It is also competitive with the quasi‐local indicators such as LP and global indicators like Katz, with a lower computational complexity than the two.
The study's overarching purpose was to investigate the impact of strategic HR outsourcing on organizational sustainability. This study also attempted to evaluate the function of organizational ...capabilities and HR proficiency as a mediator in the relationship between strategic HR outsourcing and organizational sustainability. Data was collected from 400 HR professionals in China using a questionnaire technique. The Smart-PLS software and a structural equation modeling (SEM) technique were used to evaluate the data. Organizational sustainability was found to be insignificantly related to strategic HR outsourcing. Furthermore, organizational capabilities and HR proficiency were discovered to mediate the association between strategic HR outsourcing and organizational sustainability. By analyzing the impact of strategic HR outsourcing on organizational sustainability, this paper provided an important theoretical contribution. In terms of practical applications, this article would surely help HR professionals to maintain and develop policies to encourage employees to be engaged and perform well. Furthermore, this study might be effective in resolving difficulties linked to organizational sustainability. The small sample size of this study, which included solely HR professionals working in Chinese firms, was one of its limitations. In addition, future studies can incorporate other constructs to acquire a deeper knowledge of the factors that influence employee health.
Electrochemical energy storage devices with a high energy density are an important technology in modern society, especially for electric vehicles. The most effective approach to improve the energy ...density of batteries is to search for high‐capacity electrode materials. According to the concept of energy quality, a high‐voltage battery delivers a highly useful energy, thus providing a new insight to improve energy density. Based on this concept, a novel and successful strategy to increase the energy density and energy quality by increasing the discharge voltage of cathode materials and preserving high capacity is proposed. The proposal is realized in high‐capacity Li‐rich cathode materials. The average discharge voltage is increased from 3.5 to 3.8 V by increasing the nickel content and applying a simple after‐treatment, and the specific energy is improved from 912 to 1033 Wh kg−1. The current work provides an insightful universal principle for developing, designing, and screening electrode materials for high energy density and energy quality.
Li‐ion batteries with high energy quality require a high capacity coupled with high operating voltage. This requires the electrode materials to not only have a high specific capacity but also a high discharge voltage for cathode materials and low charge voltage for anode materials.
As an extended member of the thermoelectric family, ionic thermoelectrics (i‐TEs) exhibit exceptional Seebeck coefficients and applicable power factors, and as a result have triggered intensive ...interest as a promising energy conversion technique to harvest and exploit low‐grade waste heat (<130 °C). The last decade has witnessed great progress in i‐TE materials and devices; however, there are ongoing disputes about the inherent fundamentals and working mechanisms of i‐TEs, and a comprehensive overview of this field is required urgently. In this review, the prominent i‐TE effects, which set the ground for i‐TE materials, or more precisely, thermo‐electrochemical systems, are first elaborated. Then, TE performance, capacitance capability, and mechanical properties of such system‐based i‐TE materials, followed by a critical discussion on how to manipulate these factors toward a higher figure‐of‐merit, are examined. After that, the prevalent molding methods for assembling i‐TE materials into applicable devices are summarized. To conclude, several evaluation criteria for i‐TE devices are proposed to quantitatively illustrate the promise of practical applications. It is therefore clarified that, if the recent trend of developing i‐TEs can continue, the waste heat recycling landscape will be significantly altered.
In this review, the progress in ionic thermoelectrics, including fundamental theories, material designations, property characteristics, performance regulations, molding methodologies, and device employments, are comprehensively summarized. Perspective remarks on the outlook and challenges of ionic thermoelectrics are also discussed.
Edge intelligence (EI) is recognized by academia and industry as one of the key emerging technologies for future cyber‐physical‐social systems (CPSS), which provides the ability to analyze data at ...edge rather than sending it to the cloud for analysis, and will be a key enabler to realize a world of a trillion hyper‐connected smart sensing devices. As a part of future CPSS, online social networks are large‐scale complex networks that consist of a large number of network nodes and links. The dynamic discovery of communities, especially overlapping communities, is important to understand the evolution of online social networks. However, traditional community discovery algorithms cannot effectively discover overlapping communities in social networks. In order to address this challenge, an edge intelligence‐enabled dynamic overlapping community discovery and evolution prediction model (EIDEP) is proposed in this article. This model encompasses a label propagation algorithm based extension (LPAE) algorithm, which is able to efficiently discover the user community structures in online social networks. Based on the LPAE community discovery algorithm, a user interest behavior based evolution prediction (UIBEP) algorithm is incorporated in our EIDEP model in order to realize a fast yet accurate community evolution for online social networks, by considering the interest similarity of unlinked nodes in a given community. The performance of our proposed LPAE and UIBEP models is validated and evaluated against notable state‐of‐the‐art community discovery algorithms, through extensive experiments conducted based on a Twitter dataset.
Driven by the intensive efforts in the development of high‐performance GeTe thermoelectrics for mass‐market application in power generation and refrigeration, GeTe‐based materials display a high ...figure of merit of >2.0 and an energy conversion efficiency beyond 10%. However, a comprehensive review on GeTe, from fundamentals to devices, is still needed. In this regard, the latest progress on the state‐of‐the‐art GeTe is timely reviewed. The phase transition, intrinsic high carrier concentration, and multiple band edges of GeTe are fundamentally analyzed from the perspectives of the native atomic orbital, chemical bonding, and lattice defects. Then, the fabrication methods are summarized with a focus on large‐scale production. Afterward, the strategies for enhancing electronic transports of GeTe by energy filtering effect, resonance doping, band convergence, and Rashba band splitting, and the methods for strengthening phonon scatterings via nanoprecipitates, planar vacancies, and superlattices, are comprehensively reviewed. Besides, the device assembly and performance are highlighted. In the end, future research directions are concluded and proposed, which enlighten the development of broader thermoelectric materials.
The phase transition, multiple valence bands, and resonant bonding endow GeTe with promising thermoelectric performance. Significant breakthroughs are achieved in GeTe‐based materials. This review summarizes the recent progress in developing high‐performance GeTe‐based materials and devices, including the underlying fundamentals, large‐scale production, novel strategies for boosting performance, and techniques of device assembly.
Owing to the sustainability, environmental friendliness, and structural diversity of biomass‐derived materials, extensive efforts have been devoted to use them as energy storage materials in ...high‐energy rechargeable batteries. A timely and comprehensive review from the structures to mechanisms will significantly widen this research field. Here, it starts with the operation mechanism of batteries, and it aims to summarize the latest advances for biomass‐derived carbon to achieve high‐energy battery materials, including activation carbon methods and the structural classification of biomass‐derived carbon materials from zero dimension, one dimension, two dimension, and three dimension. Each strategy starts with carefully selected examples and then moves to illustrate the underlying transport mechanism of electrons in the structure. In the end, challenges, strategies, and outlooks are pointed out for the future development of biomass‐derived carbon materials. Overall, this review will help researchers choose appropriate strategies to design biomass‐derived carbon materials, thereby promoting the application of biomass materials in battery design.
This review comprehensively summarizes the internal structure of biomass‐derived carbon materials, which aims to provide suitable environment‐friendly and low consumption green materials for high‐performance batteries design.
Acetyl-CoA represents a key node in metabolism due to its intersection with many metabolic pathways and transformations. Emerging evidence reveals that cells monitor the levels of acetyl-CoA as a key ...indicator of their metabolic state, through distinctive protein acetylation modifications dependent on this metabolite. We offer the following conceptual model for understanding the role of this sentinel metabolite in metabolic regulation. High nucleocytosolic acetyl-CoA amounts are a signature of a ‘growth’ or ‘fed’ state and promote its utilization for lipid synthesis and histone acetylation. In contrast, under ‘survival’ or ‘fasted’ states, acetyl-CoA is preferentially directed into the mitochondria to promote mitochondrial-dependent activities such as the synthesis of ATP and ketone bodies. Fluctuations in acetyl-CoA within these subcellular compartments enable the substrate-level regulation of acetylation modifications, but also necessitate the function of sirtuin deacetylases to catalyze removal of spontaneous modifications that might be unintended. Thus, understanding the sources, fates, and consequences of acetyl-CoA as a carrier of two-carbon units has started to reveal its underappreciated but profound influence on the regulation of numerous life processes.
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