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891.
Excited state dynamics of two new-type thermally activated delayed fluorescence emitters (DABNA-1 and DABNA-2) synthesised based on multiple resonance effect is studied based on first-principles calculation, and their light-emitting mechanism is explored. The excited state dynamics combing with the adiabatic energy structure of several low-lying excited states indicates that three lowest triplet states are involved in the light-emitting process. The analysis of reorganisation energy indicates different performances for two molecules in solvent and in film. Our theoretical work provides rational explanation for experimental results, and also gives clear picture for light-emitting mechanism of these new-type molecules. 相似文献
892.
A one-time pad image encryption scheme based on physical random numbers from chaotic laser is proposed and explored. The experimentally generated physical random numbers serving as the encryption keys are constructed into two random sequence image matrices, which are applied to shuffle the pixel position of the original image and change its pixel value, respectively. Some tests including statistical analysis, sensitivity analysis, and key space analysis are performed to assess reliability and efficiency of the image encryption scheme. The experimental results show that the image encryption scheme has high security and good anti-attack performance. 相似文献
893.
Pengfei Hou Yumiao Tian Prof. Yu Xie Prof. Fei Du Prof. Gang Chen Dr. Aleksandra Vojvodic Prof. Jianzhong Wu Dr. Xing Meng 《Angewandte Chemie (International ed. in English)》2023,62(32):e202304205
MXenes are 2D materials with great potential in various applications. However, the degradation of MXenes in humid environments has become a main obstacle in their practical use. Here we combine deep neural networks and an active learning scheme to develop a neural network potential (NNP) for aqueous MXene systems with ab initio precision but low cost. The oxidation behaviors of super large aqueous MXene systems are investigated systematically at nanosecond timescales for the first time. The oxidation process of MXenes is clearly displayed at the atomic level. Free protons and oxides greatly inhibit subsequent oxidation reactions, leading to the degree of oxidation of MXenes to exponentially decay with time, which is consistent with the oxidation rate of MXenes measured experimentally. Importantly, this computational study represents the first exploration of the kinetic process of oxidation of super-sized aqueous MXene systems. It opens a promising avenue for the future development of effective protection strategies aimed at controlling the stability of MXenes. 相似文献
894.
Systemic investigation on the synthesis and properties of aliphatic polylactones were carried out. And various materials were obtained with different degradation rates and mechanical properties. Two in vivo experiments were presented in this study to envision the biomedical applications of this kind of aliphatic polylactones. 相似文献