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991.
Wang  Xuejiao  Chen  Shouxian  Zhou  Pengcheng  Xiao  Feng  He  Qihang  He  Ping  Jia  Lingpu  Jia  Bin  Zhang  Hui  Liu  Hongtao  Pan  Kai  Xie  Ying 《Journal of Materials Science》2021,56(20):11894-11906
Journal of Materials Science - It is vital to exploit non-noble metal catalysts with ample natural reserve and high performance for reducing energy consumption during electrocatalytic water...  相似文献   
992.
Deng  Qin  Wei  Wenfu  Yin  Guofeng  Xie  Wenhan  Huang  Zhanglin  Ren  Junwen  Yang  Yan  Chen  Qichen  Wu  Guangning 《Journal of Materials Science》2021,56(33):18522-18533
Journal of Materials Science - Carbon material, because of its high thermal conductivity, ablation resistance and friction resistance, has been widely used in the field of electrical engineering....  相似文献   
993.
Wang  Qing  Xie  Dong  Chen  Junjia  Liu  Guang  Yu  Mingguang 《Journal of Materials Science》2021,56(23):13146-13155
Journal of Materials Science - Herein, a facile method to develop luminescent PS/AA/Rare-Earth-doped composites was presented. The PS/AA microspheres were first carried out via one-pot dispersion...  相似文献   
994.
Mechanically guided, 3D assembly has attracted broad interests, owing to its compatibility with planar fabrication techniques and applicability to a diversity of geometries and length scales. Its further development requires the capability of on-demand reversible shape reconfigurations, desirable for many emerging applications (e.g., responsive metamaterials, soft robotics). Here, the design, fabrication, and modeling of soft electrothermal actuators based on laser-induced graphene (LIG) are reported and their applications in mechanically guided 3D assembly and human–soft actuators interaction are explored. Over 20 complex 3D architectures are fabricated, including reconfigurable structures that can reshape among three distinct geometries. Also, the structures capable of maintaining 3D shapes at room temperature without the need for any actuation are realized by fabricating LIG actuators at an elevated temperature. Finite element analysis can quantitatively capture key aspects that govern electrothermally controlled shape transformations, thereby providing a reliable tool for rapid design optimization. Furthermore, their applications are explored in human–soft actuators interaction, including elastic metamaterials with human gesture-controlled bandgap behaviors and soft robotic fingers which can measure electrocardiogram from humans in an on-demand fashion. Other demonstrations include artificial muscles, which can lift masses that are about 110 times of their weights and biomimetic frog tongues which can prey insects.  相似文献   
995.
Artificial scent screening systems (known as electronic noses, E-noses) have been researched extensively. A portable, automatic, and accurate, real-time E-nose requires both robust cross-reactive sensing and fingerprint pattern recognition. Few E-noses have been commercialized because they suffer from either sensing or pattern-recognition issues. Here, cross-reactive colorimetric barcode combinatorics and deep convolutional neural networks (DCNNs) are combined to form a system for monitoring meat freshness that concurrently provides scent fingerprint and fingerprint recognition. The barcodes—comprising 20 different types of porous nanocomposites of chitosan, dye, and cellulose acetate—form scent fingerprints that are identifiable by DCNN. A fully supervised DCNN trained using 3475 labeled barcode images predicts meat freshness with an overall accuracy of 98.5%. Incorporating DCNN into a smartphone application forms a simple platform for rapid barcode scanning and identification of food freshness in real time. The system is fast, accurate, and non-destructive, enabling consumers and all stakeholders in the food supply chain to monitor food freshness.  相似文献   
996.
Engineered nano–bio cellular interfaces driven by 1D vertical nanostructures (1D-VNS) are set to prompt radical progress in modulating cellular processes at the nanoscale. Here, tuneable cell–VNS interfacial interactions are probed and assessed, highlighting the use of 1D-VNS in immunomodulation, and intracellular delivery into immune cells—both crucial in fundamental and translational biomedical research. With programmable topography and adaptable surface functionalization, 1D-VNS provide unique biophysical and biochemical cues to orchestrate innate and adaptive immunity, both ex vivo and in vivo. The intimate nanoscale cell–VNS interface leads to membrane penetration and cellular deformation, facilitating efficient intracellular delivery of diverse bioactive cargoes into hard-to-transfect immune cells. The unsettled interfacial mechanisms reported to be involved in VNS-mediated intracellular delivery are discussed. By identifying up-to-date progress and fundamental challenges of current 1D-VNS technology in immune-cell manipulation, it is hoped that this report gives timely insights for further advances in developing 1D-VNS as a safe, universal, and highly scalable platform for cell engineering and enrichment in advanced cancer immunotherapy such as chimeric antigen receptor-T therapy.  相似文献   
997.
Recent advances in the development of polymerized A–D–A-type small-molecule acceptors (SMAs) have promoted the power conversion efficiency (PCE) of all-polymer solar cells (all-PSCs) over 13%. However, the monomer of an SMA typically consists of a mixture of three isomers due to the regio-isomeric brominated end groups (IC-Br(in) and IC-Br(out)). In this work, the two isomeric end groups are successfully separated, the regioisomeric issue is solved, and three polymer acceptors, named PY-IT, PY-OT, and PY-IOT, are developed, where PY-IOT is a random terpolymer with the same ratio of the two acceptors. Interestingly, from PY-OT, PY-IOT to PY-IT, the absorption edge gradually redshifts and electron mobility progressively increases. Theory calculation indicates that the LUMOs are distributed on the entire molecular backbone of PY-IT, contributing to the enhanced electron transport. Consequently, the PM6:PY-IT system achieves an excellent PCE of 15.05%, significantly higher than those for PY-OT (10.04%) and PY-IOT (12.12%). Morphological and device characterization reveals that the highest PCE for the PY-IT-based device is the fruit of enhanced absorption, more balanced charge transport, and favorable morphology. This work demonstrates that the site of polymerization on SMAs strongly affects device performance, offering insights into the development of efficient polymer acceptors for all-PSCs.  相似文献   
998.
999.
相比于晶态合金,非晶合金表现出显著不同的氧化行为,其氧化过程受无序原子结构和非平衡状态的影响.为揭示非晶合金的早期氧化过程,需要对其氧化行为进行快速表征.本文以Zr46Cu46Al7Gd1块体非晶合金为对象,通过测量光学常数的变化对氧化行为进行表征.与X射线衍射、扫描电子显微镜和热重分析测得的结果相比,光学常数不仅可以反映非晶合金发生明显氧化的起始温度,还可以反映难以用传统方法表征的早期氧化过程.本研究结果说明光学常数是反映氧化行为的灵敏参数,将有助于认识非晶合金氧化过程随温度、时间和组分变化的演化过程.  相似文献   
1000.
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