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991.
Journal of Solid State Electrochemistry - The existing Ni cermet anodes in single-chamber solid oxide fuel cells (SC-SOFCs) usually perform poorly in hydrocarbon-air mixture owing to the...  相似文献   
992.
具有聚集诱导发光性质化合物的发展不仅很大程度上解决了传统有机分子发色团在高浓度、固态或者薄膜等形式的聚集状态下荧光猝灭的问题,而且扩展了有机发色团在荧光探针、传感器以及细胞成像等方面的应用。其中,四苯乙烯及其衍生物作为具有聚集诱导发光性质的典型化合物已被广泛应用在材料化学、生物化学等相关研究领域。受此启发,超分子化学家也将这类具有聚集诱导发光性质的四苯乙烯及其衍生物作为研究对象引入到超分子化学的领域,特别是利用大环主体与四苯乙烯客体通过主客体相互作用有效地限制了荧光客体分子的分子内转动或运动,增强了这类超分子体系的发光强度,并为其在刺激响应性传感器、智能探针等方面提供了新思路。本文总结了近年来涉及四苯乙烯衍生物与大环主体通过主客体相互作用形成聚集诱导发光超分子体系的发展,并按照大环主体进行分类简要介绍其应用。  相似文献   
993.
Chen  Zhongtao  Guo  Xinli  Liu  Yuanyuan  Zhang  Weijie  Tang  Xuan  Zheng  Yanmei  Wang  Yixuan  Li  Long  Wang  Zengmei  Zhao  Yuhong 《Journal of Solid State Electrochemistry》2019,23(5):1473-1480
Journal of Solid State Electrochemistry - Ultraflexible, wearable, transparent, and conductive films have recently attracted increasing interest due to their applicability in various electronic...  相似文献   
994.
The polyethyleneimine (PEI)-based antigen delivery system has been proved valuable for therapeutic vaccines. However, the previous bulk mixing method is not ideal to prepare PEI-base antigen- containing nanoparticles. The wide-size distribution and poor reproducibility limit its further application. In this research, we developed a microfluidic method to prepare nanopolyplexes on chips with Tesla structure to improve the fabrication. The structure and bioactivity of protein were not hampered by the shearing force in microfluidics. Comparison between physiochemical parameters suggested that the polyplexes prepared by Tesla chips were more uniform than those prepared by bulk mixing and non-Tesla chips. The reproducibility was improved obviously. The preparation was not influence much by the operating parameters such as flow rates, reagents concentration, and switching of inlets. The results indicated that it was a robust and reliable method. The data that were obtained from BMDC model demonstrated that the nanopolyplexes with optimal weight ratio had higher antigen cross-presentation efficiency than those in free antigen group. In conclusion, Tesla structured microfluidics offers a better method over bulk mixing in the preparation of PEI-based antigen-containing nanopolyplexes. It greatly expands the scope of our study and increases the potential of PEI-based antigen delivery system.  相似文献   
995.
Compared with the ripeness of olefin metathesis, exploration of the construction of carbon–carbon double bonds through the catalytic carbonyl–olefin metathesis reaction remains stagnant and has received scant attention. Herein, a highly efficient AuCl3-catalyzed intramolecular ring-closing carbonyl–olefin metathesis reaction is described. This method features easily accessible starting materials, simple operation, good functional-group tolerance and short reaction times, and provides the target cyclopentenes, polycycles, benzocarbocycles, and N-heterocycle derivatives in good to excellent yields.  相似文献   
996.
International Journal of Wireless Information Networks - A novel distributed power allocation scheme for analog network coding (ANC) in high signal-to-noise ratio (SNR) is proposed by using...  相似文献   
997.
In order to reveal electronic properties of a plutonium-gallium intermetallic compound (Pu3Ga), and its potential implication for microscopic mechanisms for effects of Ga doping on the electronic and structural properties, as well as the phase stability of delta-phase Pu Ga alloy, a first principles calculation on the magnetic properties of this system is implemented by using density functional theory (DFT) plus on-site Coulomb repulsion U with nonmagnetic, ferromagnetic, and antiferromagnetic (AFM) orders, while the intermediate correlation effect, which is beyond the scope of pure itinerant and localized electronic model, is investigated by using a many-body technique combining DFT and dynamical mean-field theory considering the dynamical correlation effect due to the incompletely filled Pu 5f orbitals and the relativistic effect by inclusion of spin-orbit coupling (SOC). Our findings show that Pu3Ga is a bad metal with AFM order, which is in good agreement with the experimental magnetic measurement. SOC further splitting Pu 5f states into j = 5/2 and j = 7/2 manifolds, the former exhibits metallic character, while the latter insulating feature. Occupation analysis establishes that an average occupancy of Pu 5f electrons in Pu3Ga is nf = 4.9598, this result together with the spectrum function indicates that 5f electrons in this system might be a localized state with strong valence fluctuation. Additionally, optimization of lattice parameter, density of state, and momentum-resolved electronic spectrum function are also presented.  相似文献   
998.
Since its discovery two decades ago, anion-π interaction has been increasingly recognized as an important driving force. Extensive theoretical and experimental efforts on the ground-state anion-π binding and recognition have laid the bases for exploring its relevance in catalysis. Accordingly, the concept of “anion-π catalysis” that employing an electron-deficient π surface (π-acidic surface) for anionic reaction intermediate and transition state stabilization has emerged. This article shortly reviews the emergence and development of this concept, aiming to provide an emphasis on the general concept and key progress in this exciting area. To highlight the essential contribution of anion-π interactions, the contents are organized according to their role engaged in catalytic process, for example from both ground-state and transition-state stabilization to solely transition-state stabilization, mainly by a single π-face, and to cooperative π-face activation. A concluding remark and outlook on future development of this field is also given.  相似文献   
999.
Developing high energy density lithium secondary batteries is pivotal for satisfying the increasing demand in advanced energy storage systems. Lithium metal batteries (LMBs) have attracted growing attention due to their high theoretical capacity, but the lithium dendrites issue severely fetter their real-world applications. It is found that reducing anion migration near lithium metal prolongs the nucleation time of dendrites, meanwhile, promoting homogeneous lithium deposition suppresses the dendritic growth. Thus, regulating ion transport in LMBs is a feasible and effective strategy for addressing the issues. Based on this, a functional separator is developed to regulate ion transport by utilizing a well-designed metal-organic frameworks (MOFs) coating to functionalize polypropylene (PP) separator. The well-defined intrinsic nanochannels in MOFs and the negatively charged gap channels both restricts the free migration of anions, contributing to a high Li+ transference number of 0.68. Meanwhile, the MOFs coating with uniform porous structure promotes homogeneous lithium deposition. Consequently, a highly-stable Li plating/stripping cycling for over 150 h is achieved. Furthermore, implementation of the separator enables LMBs with high discharge capacity, prominent rate performance and good capacity retention. This work is anticipated to aid developement of dendrite-free LMBs by utilizing advanced separators with ion transport management.  相似文献   
1000.
The application of monolithic materials as carriers for enzymes has rapidly expanded to the realization of flow-through analysis and bioconversion processes. This expansion is partly attributed to the absence from diffusion limitation in many monoliths-based enzyme reactors. Particularly, the relatively ease of introducing functional groups renders polymer monoliths attractive as enzyme carriers. After summarizing the motivation to develop enzymatic reactors using polymer monoliths, this review reports the most recent applications of such reactors. Besides, the present review focuses on the crucial characteristics of polymer monoliths affecting the immobilization of enzymes and the processing parameters dictating the performance of the resulting enzymatic reactors. This review is intended to provide a guideline for designing and applying flow-through enzymatic reactors using polymer monoliths.  相似文献   
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