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1.
Yi Yang Jinsong Wu Bei Cheng Liuyang Zhang Ahmed Abdullah Al-Ghamdi Swelm Wageh Youji Li 《结构化学》2022,(6):6-23
Single-atom catalysts have high catalytic activity due to their unique quantum size effects and optimal atom utilization. Herein, visiblelight-responsive photocatalysts were designed by coupling Cd S with graphene quantum dots(GQDs) and platinum single atoms(Pt SAs). GQDs and Pt SAs were successively loaded on ultrathin Cd S nanosheets through freeze-drying and in-situ photocatalytic reduction. The synergistic effect between Pt SAs and GQDs results in superior photocatalytic activity with a hydr... 相似文献
2.
Applied Mathematics and Mechanics - Mechanical models of residually stressed fibre-reinforced solids, which do not resist bending, have been developed in the literature. However, in some residually... 相似文献
3.
Shi-Jie Pan 《中国物理 B》2022,31(6):60304-060304
Neighborhood preserving embedding (NPE) is an important linear dimensionality reduction technique that aims at preserving the local manifold structure. NPE contains three steps, i.e., finding the nearest neighbors of each data point, constructing the weight matrix, and obtaining the transformation matrix. Liang et al. proposed a variational quantum algorithm (VQA) for NPE [Phys. Rev. A 101 032323 (2020)]. The algorithm consists of three quantum sub-algorithms, corresponding to the three steps of NPE, and was expected to have an exponential speedup on the dimensionality n. However, the algorithm has two disadvantages: (i) It is not known how to efficiently obtain the input of the third sub-algorithm from the output of the second one. (ii) Its complexity cannot be rigorously analyzed because the third sub-algorithm in it is a VQA. In this paper, we propose a complete quantum algorithm for NPE, in which we redesign the three sub-algorithms and give a rigorous complexity analysis. It is shown that our algorithm can achieve a polynomial speedup on the number of data points m and an exponential speedup on the dimensionality n under certain conditions over the classical NPE algorithm, and achieve a significant speedup compared to Liang et al.'s algorithm even without considering the complexity of the VQA. 相似文献
4.
Difeng Yin Yucen Li Lingling Xia Wenbo Li Wei Chu Jianping Yu Miao Wu Ya Cheng Ming Hu 《中国化学快报》2022,(2):1077-1080
Despite the continuously increased requirement on automated synthesis of medicines for distributed manufacturing and personal care, it remains a challenge to realize automated synthesis which requires solid-liquid phase reactions. In this work, we demonstrated an automated solid-liquid synthesis for gadopentetate dimeglumine, the most widely used magnetic resonance imaging(MRI) contrast agent. The high-efficiency reaction was performed in a 3 D microfluidic chip which was fabricated by femtoseco... 相似文献
5.
A large surface area with high active site exposure is desired for the nano-scaled electrocatalysts fabrication.Herein,taking Ni Mo O4nanorods for example,we demonstrated the advantages of the microwaveassisted hydrothermal synthesis method compared to the traditional hydrothermal approaches.Both monoclinic structured Ni Mo O4in the nanorods morphology are found for these samples but it is more time-saving and efficient in the Ni-Mo synergism for the catalyst obtained by mi... 相似文献
6.
Jing-Yi Xie Hui-Ying Zhao Yi-Wen Dong Yang Wu Da-Peng Liu Yong-Ming Chai Bin Dong 《结构化学》2022,(7):59-64
The heterojunction interfacial modulation of FeP is an effective strategy to regulate the intrinsic activity and stability, which is a major challenge to promote the industrial application of FeP-based electrocatalysts. Herein, hollow Fe4C/FeP box with heterojunction interface and carbon armor is successfully synthesized, which can expose numerous active sites and protect catalyst from corrosion. Electrochemical measurements show that Fe4C/FeP exhibits excellent hydrogen ev... 相似文献
7.
We describe an optomechanical ratchet scheme to realize nonreciprocal transmission of a light field, which is based on the bias of the optical cavity’s frequency spectrum caused by mechanical ratchet interactions. This approach to break the time-reversal symmetry of light propagation is universally valid in various optomechanical systems with ratchet-oscillator structures. We discuss specifically the implementation of an on-chip Casimir-ratchet optomechanical protocol and demonstrate the optical nonreciprocity with an extremely high isolation ratio and flexible controllability, which does not require external additional optical engineering. Our study opens a door for manipulating flexibly light propagation by using mechanical ratchet resonators, and has potential applications in the on-chip integration of nonreciprocal devices and harness of lateral Casimir forces. 相似文献
8.
Chloride ion batteries(CIB) are considered to be one of the most promising energy storage devices. As cathode materials for CIBs, metal chlorides have many advantages, such as high theoretical energy density, abundant elemental resources and ideal discharge voltage plateau. However, the dissolution and huge volume change of metal chlorides during cycling lead to considerable short lifespan, which limits their potential application for CIBs. Herein, the bismuth chloride nanocrystal is confined in... 相似文献
9.
Alcohol fuels oxidation plays a significant role in carbon sustainable cycling and high-performance catalyst with a strong anti-poisoning effect is desired. Herein, Pt-Ni alloy supported on the N-doped graphene aerogel synthesized by simple freeze-drying and annealing was demonstrated to have such catalytic ability for alcohol fuel oxidation. Pt-Ni alloy particles were found uniformly dispersed over the surface of 3D N-doped graphene aerogel. High anti-poisoning ability for CO-like intermediates... 相似文献
10.
JinLei Wu Shuai Tang Yan Wang XiaoSai Wang JinXuan Han Cheng Lü Jie Song ShiLei Su Yan Xia YongYuan Jiang 《中国科学:物理学 力学 天文学(英文版)》2022,(2)
Nonadiabatic holonomic quantum transformations(NHQTs)have attracted wide attention and have been applied in many aspects of quantum computation,whereas related research is usually limited to the field of quantum physics.Here we bring NHQTs into constructing a unidirectional acoustic metamaterial(UDAM)for shaping classical beams.The UDAM is made up of an array of three-waveguide couplers,where the propagation of acoustic waves mimics the evolution of NHQTs.The excellent agreement among analytical predictions,numerical simulations,and experimental measurements confirms the great applicability of NHQTs in acoustic metamaterial engineering.The present work extends research on NHQTs from quantum physics to the field of classical waves for designing metamaterials with simple structures and may pave a new way to design UDAMs that would be of potential applications in acoustic isolation,communication,and stealth. 相似文献