A novel RhB@MOF-808 fluorescent probe for the rapid detection of dopamine and Fe3.

Dopamine (DA) and Fe3+ as the important bioactive ingredients, playing an indispensable role in human metabolism. Therefore, developing the accurate detection of DA and Fe3+ is of great significance for disease screening. Herein, we put forward a simple, rapid, and sensitive fluorescent detection strategy for the detection of dopamine and Fe3+ based on Rhodamine B-modified MOF-808 (RhB@MOF-808). RhB@MOF-808 produced strong fluorescence at 580 nm, and the fluorescence was significantly quenched after DA or Fe3+ was added, which was regarded as a static quenching process. Detection limits are as low as 60.25 nM and 48.34 nM, respectively. Furthermore, based on the responses of DA and Fe3+ to the probe, molecular logic gates were successfully designed. More importantly, RhB@MOF-808 had excellent cell membrane permeability and had been successfully used to label DA and Fe3+ in Hela cells, which presented a potential biological application value as a fluorescent probe for detecting DA and Fe3+.

Self-calibrated paper-based nanoarrays for background-free quantitative detection of pesticides using self-assembly and mask-assisted techniques.

Flexible surface-enhanced Raman scattering (SERS) has received considerable attention in the field of rapid analysis. However, obtaining accurate quantitative SERS results remains challenging. Here, we develop a SERS sensor based on self-assembly and mask-assisted techniques for the precise transfer of Au@PB@Ag nanoarrays onto filter paper. Prussian blue (PB) as an internal standard (IS) is used to calibrate the fluctuations in the SERS signal induced by the microstructure of the filter paper, and can generate a local plasmon resonance under a Raman laser at a wavelength of 633 nm, which enables a dual electromagnetic enhancement of the internal self-calibration and external target molecule signals. The SERS substrate has a low limit of detection of 3.96 × 10-9, a uniformity relative standard deviation (RSD) of 9.94 % (16.85 % uncalibrated), a repeatability RSD of 9.43 % (31.2 % for Au@Ag NPs), and remains stable for more than 45 days. Thiram and thiabendazole in fruit juices can be quantitatively detected using patterned transfer monolayer arrays with a common dropper. The R2 coefficients of the pesticide concentration and Raman intensity fitting curves improved from 0.9659 and 0.9499 to 0.9976 and 0.9928, respectively. Thus, paper-based Au@PB@Ag nanoarrays have facilitated the development of SERS technology for practical applications.

Skill Movement Trajectory Recognition of Freestyle Skiing U-Shaped Field Based on Deep Learning and Multitarget Tracking Algorithm.

Freestyle skiing U-shaped field is a snow sport that uses double boards to perform a series of action skills in a U-shaped pool, which requires very high skills for athletes. In this era of deep learning, in order to develop a more scientific training method, this paper combines multitarget tracking algorithm and deep learning to conduct research in freestyle skiing U-shaped venue skills motion capture. Therefore, this paper combines the convolutional neural network and multitarget tracking algorithm in deep learning to study the human action recognition technology, and then uses the LSTM module to study the freestyle skiing U-shaped venue skills. Finally, this paper designs the training method of the action recognition algorithm of the freestyle U-shaped skiing skills multitarget tracking algorithm based on deep learning. This paper also designs multitarget tracking dataset experiments and model updating experiments. Based on the data of experimental analysis, the training method designed in this paper is optimized, and finally compared with the traditional training method. Compared with the traditional freestyle U-shaped skiing skills training method, the experimental results show that the training method of the freestyle U-shaped skiing skills multitarget tracking algorithm action recognition algorithm is based on deep learning designed in this paper and this improves the skill score by 14.48%. Most professional students are very satisfied with the training method designed in this paper.

Visualization of vibrational-resolution charge transfer enhanced resonance Raman scattering spectroscopy.

In this paper, we report visualization of vibrational-resolution charge transfer enhanced resonance Raman scattering Spectroscopy. Based on the first-principles calculation method, we calculated and analyzed the electronic excitation characteristics of the molecules as well as the spontaneous Raman and resonance Raman spectra. Through the visualization of the electronic excitation characteristics, it is found that the Raman signal of the atomic group vibration mode occupied by the charge transfer excitons is significantly enhanced. Super-exchange charge transfer excitons enhance the polarizability by enhancing the dipole moment, ultimately enhancing the Raman optical signal.