No abstract

While concerns about improving recharged afterglow intensity in vivo still motivate further exploration, afterglow nanoparticles (AGNP) offer unique optical merit for autofluorescence‐free biological imaging. Apart from efforts enhancing the afterglow emission properties of AGNP, improving afterglow excitation response to visible or near infrared light is important but has lacked success. Dye sensitization has been used to improve the optical response of photovoltaic nanomaterials and to enhance upconversion luminescence efficiency. This concept has recently been expanded and applied to AGNPs. As a new multifunctional nanoprobe, such dye‐sensitized AGNP takes advantage of both high spatial resolution fluorescence imaging and sensitive afterglow imaging. This Concept introduces the background, the concept, mechanism, and related imaging application, as well as reviewing existing challenges and proposing future developmental directions for the dye‐sensitized AGNPs.

No abstract

Abnormal vibration may occur in the pipeline of cooling and lubrication system of synchronous condenser during operation. In order to solve this problem, a priori analysis method for abnormal vibration of synchronous condenser piping system is proposed in this paper. This method mainly includes three parts :(1) the modal analysis of the whole pipeline system is carried out to find the pipeline with the most dangerous abnormal vibration; (2) Analyze the cause of abnormal vibration of the hazardous pipeline; (3) According to the analysis results of vibration causes, the field measurement is carried out, the modal analysis is verified, and then the cause and location of abnormal vibration of the whole pipeline system are determined. The results of case analysis show that this scheme can quickly and accurately find out the cause and location of abnormal vibration of the synchronous condenser pipeline system, improve detection efficiency and save cost. At the same time, the natural frequency of vibration obtained by modal analysis can provide a theoretical basis for the design and transformation of the synchronous condenser pipe system.

<abstract><p>Nakamoto consensus is prevailing in the world largest blockchain-based cryptocurrency systems, such as Bitcoin and Ethereum. Since then, various attempts have been studied to attack Nakamoto consensus worldwide. In recent years, network delay has won more attention for making inconsistent ledgers in blockchain-based applications by virtue of attacking Nakamoto consensus. However, so far as we know, most of the existing works mainly focus on constructing inconsistent ledgers for blockchain systems, but not offering fine-grained theoretical analysis for how to optimize the success probability by flexibly dividing computational power and network delay from the viewpoint of adversary. The paper first utilizes network delay and the partition of controlled computation power of honest miners for making forks as long as possible. Then, formally analysis is provided to show the success probability of the proposed attack, and compute the optimal network delay and splitting for adversarial computation power in theory. Finally, simulation experiments validate the correctness of the formal analysis.</p></abstract>