Henan Normal University

About: Henan Normal University is a education organization based out in Xinxiang, China. It is known for research contribution in the topics: Catalysis & Ionic liquid. The organization has 10863 authors who have published 11077 publications receiving 166773 citations.

Synthesis of novel C6-phosphonated purine nucleosides under microwave irradiation by SNAr-Arbuzov reaction.

Abstract: Novel C6-phosphonated purine nucleosides were obtained in good to excellent isolated yields by the simple and catalyst-free SNAr-Arbuzov reaction of trialkyl phosphite with 6-choloropurine nucleosides, including a series of nonsugar carbon nucleosides. Shorter reaction times were needed, and substantially higher yields were obtained under microwave irradiation conditions compared with conventional heating conditions.

Colour light field image encryption based on DNA sequences and chaotic systems

Abstract: The light field image (LFI) information includes the intensity of the collected object and the direction of the light through recording. An LFI with a 4-D scene representation includes a 2-D spatial domain and a 2-D angular domain, which is completely different than general natural images. To date, the encryption of natural images has been widely studied, while the encryption design of the LFI is missing. This work proposes an encryption scheme for colour LFI based on DNA sequences and chaotic systems. First, we employ an angular domain plane to represent the multi-view image of the LFI and then obtain a sub-view image in the spatial domain. For the given sub-view image and the random matrix, we apply a block processing method to divide multiple sub-blocks. Then, the DNA sequence and the chaotic system are used to encrypt the sub-view image. Moreover, considering the relationship between two planes, we apply the Arnold transform for all the sub-view images to realize the final encryption. Through three statistical analyses, three resistance attack analyses and two key analyses, experimental results show that the proposed scheme can be applicable, reliable, and secure enough.

Interlayer coupling and external electric field tunable electronic properties of a 2D type-I α-tellurene/MoS2 heterostructure

Abstract: α-Tellurene, a recently theoretically and experimentally accessible Group-VI two-dimensional (2D) material, has attracted considerable attention. Owing to its unique structure being similar to that of 2D transition metal dichalcogenides (TMDs), the studies of 2D van der Waals heterostructures (vdWHs) based on α-tellurene/TMDs will be very interesting. In this work, we designed an α-tellurene/MoS2 vdWH and investigated its electronic properties by using the first-principles method. Our results have suggested that such an α-tellurene/MoS2 vdWH possesses an obvious type-I band alignment with an indirect band gap of approximately 0.77 eV. Moreover, we have also found that an intriguing type-I to type-II or indirect to nearly direct transition can be induced by increasing the interlayer coupling of the heterostructure or applying an external electric field. Overall, these findings provide a promising route to tune the electronic properties and design new α-tellurene-based vdWHs for applications in electronic and optoelectronic devices.