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991.
992.
Yaohui Lv Kai Huang Wei Zhang Songlin Ran Fangli Chi Bin Yang Xianguo Liu 《Crystal Research and Technology》2014,49(2-3):109-115
Octahedrally shaped NiO powders have been synthesized via a one‐step composite‐hydroxide‐mediated method without any surfactant. The synthesized materials are characterized by XRD, EDS, TEM and FESEM techniques. Each particle exhibited a nearly perfect octahedron shape with sharp edges and corners as well as smooth surfaces. The octahedral NiO particles performed better gas‐sensitivity toward ethanol than that of NiO nanopowders, which was attributed to the exposed {111} facets of octahedron. The result was confirmed by the first‐principle calculation which indicated that the (111) facet was more active than (100) and (110) facet. 相似文献
993.
Optical Review - Temporal phase unwrapping based on phase-encoding is a technique widely used in 3D measurement for its high-speed advantage. However, eliminating fringe order jump error induced by... 相似文献
994.
Controlled Self-Assembly of Discrete Amphiphilic Oligourethanes with a Cascade Self-Immolative Motif
Jie Xu Changzhu Lv Dr. Qiangqiang Shi Jialin Zhang Ning Wang Prof. Dr. Guoying Zhang Prof. Dr. Jinming Hu Prof. Dr. Shiyong Liu 《Angewandte Chemie (International ed. in English)》2023,62(33):e202306119
Discrete polymers offer an excellent platform for comprehending the interplay between precise chain structures, distinctive self-assembly behavior, and functional applications, whereas the development of discrete polymers with self-immolative properties remains scarce. Here, we modularly synthesize a library of discrete self-immolative oligourethanes containing N-naphthylcarbamate or N-(3-fluorophenyl)carbamate repeating units via iterative stepwise growth. These oligourethanes undergo not only cascade 1,6-elimination depolymerizations via photo-mediated removal of o-nitrobenzyl carbamate triggers but also selective cleavage of benzyl-O linkages under MS/MS conditions even without UV light irradiation. In aqueous media, these discrete oligourethanes self-assemble into different morphologies such as flat nanosheets, nanofibers, and nanoribbons, depending on the chain lengths and backbone compositions, and further morphological transitions are observed upon thermal annealing. 相似文献
995.
Rui Zhang Ge Cheng Mengxuan Li Hongying Lv Juan Li 《Particle & Particle Systems Characterization》2023,40(5):2200174
Singlet fission (SF), whereby a singlet exciton is converted into a pair of triplet excitons, can improve the efficiency of solar cells. Pentacene has been extensively studied as the most promising SF compound, owing to its 200% yield of triplet states. However, the easy degradation of pentacene in the presence of light and air owing to photooxidation cannot be explained by the classical 1O2 generation mechanism. To address this issue, in the present study, pentacene nanorods (Pc NRs) are prepared as a novel photosensitizer (PS); self-carried Pc NRs exhibited higher 1O2 generation capacity. Thus, a novel 1O2 generation mechanism is proposed based on the SF effect. The initial photon absorption occurs to access single-exciton states, S1–S3. Excited-state Pc pairs accelerate the SF effect in pentacene NRs, leading to a non-adiabatic transition to the dark D state. Dark D state is a singlet state by two triplets coupled overall, and it can transfer its energy to 3O2 for generating 1O2. Using Pc NRs as PSs, photodynamic therapy (PDT) inhibits tumor growth in 4T1 tumor-bearing mice upon 405-nm-wavelength and 650-nm-wavelength laser irradiations. This study paves the way to discover novel PSs that are not considered with classical 1O2 generation mechanisms. 相似文献
996.
Tingxiang He Shenghua Lv Dequan Wei Rui Feng Juhui Yang Yihan Yan Leipeng Liu Lei Wu 《Chemical record (New York, N.Y.)》2023,23(11):e202300184
Traditional energy from fossil fuels like petroleum and coal is limited and contributes to global environmental pollution and climate change. Developing sustainable and eco-friendly energy is crucial for addressing significant challenges such as climate change, energy dilemma and achieving the long-term development of human society. Biomass hydrogels, which are easily synthesized and modified, have diverse sources and can be designed for different applications. They are being extensively researched for their applications in artificial intelligence, flexible sensing, biomedicine, and food packaging. The article summarizes recent advances in the preparation and applications of biomass-based photothermal conversion hydrogels, discussing the light source, photothermal agents, matrix, and preparation methods in detail. It also explores the use of these hydrogels in seawater desalination, photothermal therapy, antibacterial agents, and light-activated materials, offering new ideas for developing sustainable, efficient, and advanced photothermal conversion biomass hydrogel materials. The article concludes with suggestions for future research, highlighting the challenges and prospects in this field and paving the way for developing of long-lasting, efficient energy materials. 相似文献
997.
In this paper, a Volterra model with mutual interference and Holling III type functional response is investigated, some sufficient conditions which guarantee the existence and global attractivity of a positive periodic solution for the system are obtained and two examples are given to verify the results by using MatLab. Furthermore, our results improve the main results in the literature. 相似文献
998.
Guangying Lv 《Journal of Mathematical Analysis and Applications》2010,370(1):82-100
In this paper, we study the existence, uniqueness and profiles of traveling waves to some integral-differential equations arising from nonlinear nonlocal neuronal networks with oscillatory kernels. Our approach is fundamental ideas in differential equation and function analysis. 相似文献
999.
The purpose of this paper is twofold: (1) to examine strengths and weaknesses of recently developed optimization methods for selecting radiation treatment beam angles and (2) to propose a simple and easy-to-use hybrid framework that overcomes some of the weaknesses observed with these methods. Six optimization methods—branch and bound (BB), simulated annealing (SA), genetic algorithms (GA), nested partitions (NP), branch and prune (BP), and local neighborhood search (LNS)—were evaluated. Our preliminary test results revealed that (1) one of the major drawbacks of the reported algorithms was the limited ability to find a good solution within a reasonable amount of time in a clinical setting, (2) all heuristic methods require selecting appropriate parameter values, which is a difficult chore, and (3) the LNS algorithm has the ability to identify good solutions only if provided with a good starting point. On the basis of these findings, we propose a unified beam angle selection framework that, through two sequential phases, consistently finds clinically relevant locally optimal solutions. Considering that different users may use different optimization approaches among those mentioned above, the first phase aims to quickly find a good feasible solution using SA, GA, NP, or BP. This solution is then used as a starting point for LNS to find a locally optimal solution. Experimental results using this unified method on five clinical cases show that it not only produces consistently good-quality treatment solutions but also alleviates the effort of selecting an initial set of appropriate parameter values that is required by all of the existing optimization methods. 相似文献
1000.
Xiangyang Li Haifeng Lv Xiaofeng Liu Tong Jin Xiaojun Wu Xingxing Li Jinlong Yang 《中国科学:化学(英文版)》2021,(12):2212-2217
Exploring two-dimensional (2D) magnetic semiconductors with room-temperature magnetic ordering and electrically controllable spin-polarization is a highly desir... 相似文献