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The purpose of exploring the development mode of online teaching resources in colleges and universities is to enhance the utilization rate of online teaching resources to promote the diversification of teaching methods. In this paper, based on big data technology, a cloud education platform integrating online teaching resources in colleges and universities is constructed under the perspective of integrating industry and education, and the architecture and functions of the cloud education platform are explained. Then the collaborative filtering algorithm is used to filter and collect the information on online teaching resources, and the Pearson correlation formula is used to pre-process the data and help users to recommend teaching resources. Finally, the pre-processed data are filtered and analyzed using the multilayer perceptron technology under the deep learning model. To verify the practicality of the cloud education platform proposed in this paper, the platform’s performance is evaluated by combining MAE metrics with RMSE metrics. In terms of load capacity, the platform has the best load capacity when the number of users is 200. From the performance test, the average transmission rate of the cloud education platform is 8.1% and 0.93% higher than that of NetEase Cloud Classroom and Tencent Classroom, and the average transmission time is 7.09 s. From the practicality analysis, the average value of the MAE index is 0.317%, and the average value of the RMSE index is 0.232%. This shows that the cloud education platform can effectively integrate university online teaching resources and help universities achieve diversified development of teaching methods.

The development of two-dimensional (2D) materials has received wide attention as a generation of optoelectronics, thermoelectric, and other applications. In this study, a novel 2D material, PbN, is proposed as an elemental method using the prototype of a recent reported nitride (J. Phys. Chem. C 2023, 127, 43, 21,006-21014). Based on first-principle calculations, the PbN monolayer is investigated as stable at 900 K, and the isotropic mechanical behavior is addressed by the Young's modulus and Poisson's ratio at 67.4 N m-1 and 0.15, respectively. The PbN monolayer also presents excellent catalytic performance with Gibbs free energy of 0.41 eV. Zero bandgap is found for the PbN monolayer, and it can be opened at about 0.128 eV by forming a heterostructure with CdO. Furthermore, the PbN/CdO is constructed by Van der Waals interaction, while the apparent potential drop and charge transfer are investigated at the interface. The PbN/CdO heterostructure also possesses excellent light absorption properties. The results provide theoretical guidance for the design of layered functional materials. [ABSTRACT FROM AUTHOR]

Two-dimensional materials are widely used as a new generation of functional materials for photovoltaic, photocatalyst, and nano-power devices. Strain engineering is a popular method to tune the properties of two-dimensional materials so that performances can be improved or more applications can be obtained. In this work, a two-dimensional heterostructure is constructed from SiC and GaN monolayers. Using first-principle calculations, the SiC/GaN heterostructure is stacked by a van der Waals interaction, acting as a semiconductor with an indirect bandgap of 3.331 eV. Importantly, the SiC/GaN heterostructure possesses a type-II band structure. Thus, the photogenerated electron and hole can be separated in the heterostructure as a potential photocatalyst for water splitting. Then, the external biaxial strain can decrease the bandgap of the SiC/GaN heterostructure. From pressure to tension, the SiC/GaN heterostructure realizes a transformation from a type-II to a type-I semiconductor. The strained SiC/GaN heterostructure also shows suitable band alignment to promote the redox of water splitting at pH 0 and 7. Moreover, the enhanced light-absorption properties further explain the SiC/GaN heterostructure's potential as a photocatalyst and for nanoelectronics. [ABSTRACT FROM AUTHOR]

In this work, As/PtSe2 vdW heterostructure is discussed, and the structure, electronic and optical properties of the heterostructure are quested. According to the first-calculation principle, energy band values of monolayered As and monolayered PtSe2 are calculated, which are 2.44 and 1.94 eV, respectively. To dig more potential properties of 2D materials, van der Waals force is used to connect monolayered As and monolayered PtSe2 to form a vertical heterostructure, and the energy band value of As/PtSe2 vdW heterostructure is calculated, which is 0.942 eV. Meanwhile, the heterostructure also displays type-II, which can continuously separate photogenerated electrons–holes. When studying the interface of As/PtSe2 vdW heterostructure, it is found that the charge has changed obviously. The reason for this change is that As acts as a donor layer and contributes 0.0474 |e| electrons to PtSe2, which further explains that there is a weak van der Waals force between As layer and PtSe2 layer. Finally, As/PtSe2 vdW heterostructure has an excellent light trapping ability, especially in the vicinity of the visible spectrum and near infrared, which has dramatically improved the optical properties of monolayered As and monolayered PtSe2, and is a excellent potential photocatalyst. [ABSTRACT FROM AUTHOR]

Two-dimensional materials present abundant novel properties when used in advanced applications, which develops considerable focus. In this investigation, the first-principles calculations are explored to study the structural characteristic of the monolayered SiP2, which is stable even at 1200 K. The SiP2 monolayer is a semiconductor with an indirect bandgap of 2.277 eV. The decent band alignment and light absorption capacity imply that the application is a suitable photocatalyst for water splitting. Furthermore, the SiP2 monolayer possesses an ultrafast electron mobility at 33,153 cm2·V−1·s−1 in the transport direction. The excellent Gibbs free energy of the SiP2 monolayer is also addressed in an examination of the hydrogen evolution reaction. [ABSTRACT FROM AUTHOR]

This study aimed to synthesize silica-coated gold (Au@SiO 2 ) nanoparticles coupled to antibodies against the scavenger receptor class B type I (SR-BI) and investigate their potential ability of visual tracking and treatment of cervical cancer. The fluorescein isothiocyanate (FITC)-labeled Au@SiO 2 -SR-BI antibody was synthesized, followed by characterization determination. The expression and location of SR-BI protein in cervical cancer cells were respectively detected by western blot and immunofluorescence assays. The effects of nanoparticles on cancer cells were determined by adsorption assay and apoptosis detection, respectively. The effects of nanoparticles on tumor formation in nude mice were determined. The particle sizes of Au@SiO 2 ranged from 2-2.5 μm, and the particle size distribution was relatively uniform. MS751 showed the highest expression of SR-BI. SR-BI was located in the cytomembrane. There were more FITC-Au@SiO 2 -SR-BI nanoparticles on the surface of the cells compared to FITC-Au@SiO 2 . Significant apoptosis was observed in the FITC-Au@SiO 2 -SR-BI-treated group in both MS751 and H8 cells. Photothermal ablation of solid tumors was observed when FITC-Au@SiO 2 -SR-BI was activated using 808 nm wave. Expressions of the apoptosis-related markers including BCL2, BCLX, and p-AKT were significantly decreased, while those of caspase 3 and caspase 8 were significantly increased. The study presented a novel antibody-conjugated Au@SiO 2 nanoparticle specifically targeting molecular receptors on cancer cell membranes. Antibody-conjugated Au@SiO 2 nanoparticles may have therapeutic potential for the treatment of cervical cancer., Competing Interests: None., (AJTR Copyright © 2022.)

Recently, expanding the applications of two-dimensional (2D) materials by constructing van der Waals (vdW) heterostructures has become very popular. In this work, the structural, electronic and optical absorption performances of the heterostructure based on AlN and Zr 2 CO 2 monolayers are studied by first-principles simulation. It is found that AlN/Zr 2 CO 2 heterostructure is a semiconductor with a band gap of 1.790 eV. In the meanwhile, a type-I band structure is constructed in AlN/Zr 2 CO 2 heterostructure, which can provide a potential application of light emitting devices. The electron transfer between AlN and Zr 2 CO 2 monolayer is calculated as 0.1603 | e | in the heterostructure, and the potential of AlN/Zr 2 CO 2 heterostructure decreased by 0.663 eV from AlN layer to Zr 2 CO 2 layer. Beisdes, the AlN/Zr 2 CO 2 vdW heterostructure possesses excellent light absorption ability of in visible light region. Our research provides a theoretical guidance for the designing of advanced functional heterostructures., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Ren, Zheng, Lou, Yu, Sun and Li.)