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1.
International Journal of Theoretical Physics - We consider the stationary state of a spin-orbit coupled (SOC) binary Bose-Einstein condensates with dipole-dipole interaction (DDI). Our results are...  相似文献   
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The drug delivery system based on nano/micromotors has become a research hot spot in recent years. However, naked micromotors may be ruptured or passivated under the complex biological environment, which will result in the leakage of drugs in advance or limited self-propulsion performance. Herein, an injectable micromotor@hydrogel drug delivery system to protect micromotors from the external environment is proposed. The micromotors were prepared through layer-by-layer assembly technology. The asymmetric decomposition of hydrogen peroxide catalyzed by the locally distributed platinum nanoparticles enabled efficient propulsion of the micromotors in low concentration of hydrogen peroxide. In order to protect micromotors, they were loaded into the Schiff base hydrogel. The micromotor@hydrogel system can be injected directly into the lesion to release micromotors in response to the environment, reducing external influence on micromotors and improving the sustained-release effect. Erythromycin (Ery) loaded into the micromotors and the micromotor@hydrogel system demonstrated excellent antibacterial effect. Micromotors released from the hydrogel underwent enhanced diffusion in the surroundings of bacteria without addition of exogenous hydrogen peroxide, which was manifested by their appearance in edge of the inhibition zone. The proposed micromotor@hydrogel drug delivery system offers a new strategy for the treatment of bacterial infections.  相似文献   
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Cubic-like CaTaO2N photocatalysts with high crystallinity and uniform particle size were successfully prepared by the flux-assisted nitridation method. The growth of CaTaO2N single crystals under different synthesis conditions was systematically investigated to understand the effects of the crystallinity and optical property on photocatalytic performance of CO2 reduction. Moreover, the modification of CaTaO2N single crystals with core-shell Ni−Ag bicomponent cocatalyst by two-step decoration process gave a 2.4 times higher amount of CO evolution than the deposition of sole Ag cocatalyst, because of the synergistic effects of bicomponent cocatalyst on the interfacial electron transfer and surface catalytic process. This study provides a valuable way to construct high-crystalline photocatalysts with effective bicomponent cocatalyst for visible-light-driven CO2 reduction with H2O.  相似文献   
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Science China Chemistry - Destructive quantum interference (DQI) provides a unique approach to controlling the leakage current in the OFF state of molecular devices. However, the DQI in...  相似文献   
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The direct gem-difluoroalkenylation of X−H bonds represents the most straightforward approach to access heteroatomic gem-difluoroalkenes that, as the isostere of the carbonyl group, have great potency in drug discovery. However, the construction of tetrasubstituted heteroatomic gem-difluoroalkenes by this strategy is still an unsolved problem. Here, we report the first direct X−H bond gem-difluoroalkenylation of amines and alcohols with trifluoromethyl ketone N-triftosylhydrazones under silver (for (hetero)aryl hydrazones) or rhodium (for alkyl hydrazones), thereby providing a most powerful method for the synthesis of tetrasubstituted heteroatomic gem-difluoroalkenes. This method features a broad substrate scope, high product yield, excellent functional group tolerance, and operational simplicity (open air conditions). Moreover, the site-specific replacement of the carbonyl group with a gem-difluorovinyl ether bioisostere in drug Trimebutine and the post-modification of bioactive molecules demonstrates potential use in medicinal research. Finally, the reaction mechanism was investigated by combining experiments and DFT calculations, and disclosed that the key step of HF elimination occurred via five-membered ring transition state, and the difference in the electrophilicity of Ag- and Rh-carbenes as well as the multiple intermolecular interactions rendered the effectiveness of Rh catalyst selectively for alkyl hydrazones.  相似文献   
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Zhang  Junyu  Hong  Mingyi  Zhang  Shuzhong 《Mathematical Programming》2022,194(1-2):901-935
Mathematical Programming - In this paper, we study the lower iteration complexity bounds for finding the saddle point of a strongly convex and strongly concave saddle point problem: $$\min _x\max...  相似文献   
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研究了基于G-N模型与三项延迟模型的热弹性波的传播特征.在各种广义热弹性理论中,热位移概念的引入使得G-N模型具有独特性质而引起广泛的关注和应用.基于G-N模型,最近一个三相延迟模型被提出.主要研究了这两种模型下第一和第二声波(耦合热弹性波)的色散和衰减特性,分析了温度场和位移场在两种模型下的振幅比和相位差.结果发现三相延迟模型更为通用和灵活,应得到更多的关注与应用.  相似文献   
10.
Mao  Jin-Chao  Hong  Jin-Jing  Lin  Ming-Zheng  Han  Feng  Li  Dong 《Journal of fluorescence》2021,31(4):1169-1176
Journal of Fluorescence - A new Zn(II)-bearing metal-organic framework (MOF), namely, {[Zn2(L)2(H2O)]·8H2O·DMF}n (1) has been generated via applying...  相似文献   
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