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991.
本文在典型的里德伯电磁感应透明系统中研究弱探测场在相互作用原子系统中的传播特性,重点关注基于偶极阻塞效应的探测场相位的合作光学非线性行为.通过与探测场透射率和光子关联作对比,发现相位的光学响应具有新特性:共振和Autler-Townes劈裂条件下相位对入射场强和初始光子关联不敏感,而在两者之间的频率范围内相位响应具有非线性特征,尤其在经典光频率处最显著.此外,提高主量子数和原子密度都会促进相位的非线性效应.综上,与探测场透射率和光子关联一样,相位可以作为合作光学非线性的另一个标识来刻画非线性现象,对里德伯电磁感应透明研究是一个有力的补充. 相似文献
992.
Science China Chemistry - The defects in the ceria usually work as the active reaction sites in their industrial applications. In this article, we studied the formation and atomic process of the... 相似文献
993.
Isomerism of atomically precise noble metal nanoclusters provides an excellent platform to investigate the structure–property correlations of metal nanomaterials. In this study, we performed density functional theory (DFT) and time‐dependent (TD‐DFT) calculations on two Au21(SR)15 nanoclusters, one with a hexagonal closed packed core (denoted as Au21 hcp ), and the other one with a face‐centered cubic core (denoted as Au21 fcc ). The structural and electronic analysis on the typical Au–Au and Au–S bond distances, bond orders, composition of the frontier orbitals and the origin of optical absorptions shed light on the inherent correlations between these two clusters. 相似文献
994.
Abdillah Sani Bin Mohd Najib Xiaobo Peng Ayako Hashimoto Shusaku Shoji Takayuki Iida Yunxing Bai Hideki Abe 《化学:亚洲杂志》2019,14(16):2802-2805
Mesoporous precious metals with abundant active sites and high surface area have been widely recognized as high‐performance catalytic materials. However, the templated synthesis is complex and costly. Herein, we report a mesoporous rhodium (m‐Rh) that can be readily synthesized from entangled nanofibres of Rh and Y2O3 without templates. The entangled nanofibres, prepared from uniform Rh‐Y alloys under redox atmosphere, were the key precursor in the synthesis processes. Moreover, the m‐Rh efficiently catalyzed carbon dioxide reforming of methane (DRM) at a low reaction temperature of 683 K. Further, electrochemical methods of CO electro‐oxidation were innovatively used to demonstrate the stability of CO and oxygen species for the DRM reaction. 相似文献
995.
Shanshan Guo Rongyuan Lei Xinmiao Liang Jiyan Liu Xueqing Liu Shuyu Gao Xianghong Peng Shilong Bian Yangwei Chen Yi Jin Shaojun Cai Zhihong Liu Jiwen Feng 《化学:亚洲杂志》2019,14(9):1404-1408
Artificial intelligence sensations have aroused scientific interest from electronic conductors to bio‐inspired ionic conductors. The conductivity of electrons decreases with increasing temperature, while the ionic conductivity agrees with an Arrhenius equation or a modified Vogel–Tammann–Fulcher (VTF) equation. Herein, thermo‐responsive poly(N‐isopropyl amide) (PNIPAm) and single‐ion‐conducting poly(2‐acrylamido‐2‐methyl‐1‐propanesulfonic lithium salt) (PAMPSLi) were copolymerized via a facile radical polymerization to demonstrate a very intriguing anti‐Arrhenius ionic conductivity behaviour during thermally induced volume‐phase transition. These smart hydrogels presented very promising scaffolds for architecting flexible, wearable or advanced functional ionic devices. 相似文献
996.
Jing-Jing Bai Jing-Ting Zhang Bing-Xiao Liu Jing-Jing Cui Xiu-Rong Hou 《Journal of Macromolecular Science: Physics》2019,58(3):425-441
Using monomer-functionalized nanofiller to prepare polymeric nanocomposites is a promising strategy toward achieving enhanced performance. In this study toluene-2,4-diisocyanate (TDI), one of the monomers used for synthesizing polyurethane, was covalently functionalized on graphene oxide (GO) and then the functionalized GO (TDI-GO) was polymerized with polycaprolactone diol (PCL) via in-situ polymerization, leading to chemically linked polyurethane nanocomposites through the covalent bonds between the isocyanate groups on GO and the hydroxyl-terminated PCL. Fourier transform infrared spectroscopy (FTIR), X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD) and dispersion experiments of the nanofillers demonstrated that the TDI was successfully grafted onto the GO. The rheological properties were investigated to establish the structure-property relationships of the nanocomposites. The storage moduli (G’), loss moduli (G”) and complex viscosity (η*) of the samples increased monotonically with TDI-GO content, which is attributed to the strong polymer-filler interactions and the effective dispersion of the nanofillers. Additionally, the tan δ variation with frequency, the intersection of G’ and G”, Han plots, van Gurp-Palmen plots and Cole-Cole plots all showed that the incorporation of TDI-GO decreased the degree of microphase separation and improved the elastic properties of the nanocomposites. We suggest this is related to the enhanced interactions between the polymer and nanofillers, which strongly restricted the mobility and relaxation of the polymer chains. 相似文献
997.
In the study, an improved superconducting heterojunction is made up of a zigzag graphene nanoribbon, which is patterned by a triangle and supports localized edge mode. Since all the localized edge modes stem from a pattern operation, the structure features of the pattern exert an enormous function on the coherent quantum transport. Especially, the patterned modes can enhance the Andreev reflection largely both in the ferromagnetic nanoribbon edge and the antiferromagnetic nanoribbon edge. The spin resolved zero bias conductances, in sharp contrast to its counterpart in the infinite width superconducting heterojunction, exhibit the different dependence on the patterned ferromagnetic interaction. 相似文献
998.
Dr. Jinpeng Liu Dr. Nali Zhu Dr. Haiming Xu Jinwu Bai Dr. Chaofeng Shao Prof. Meiting Ju Prof. Qilin Yu Prof. Lu Liu 《ChemistryOpen》2019,8(10):1309-1315
Bismuth oxybromide (BiOBr) nanosheets are exciting photocatalysts for microbial disinfection and organic dye degradation. However, it remains a great challenge to easily recycle these nanomaterials and improve their photocatalytic ability. Herein, we constructed a novel photocatalytic BiOBr@PAG gel containing BiOBr nanosheets and polyacrylamide gel (PAG), based on peroxydisulfate-induced polymerization reaction. The photocatalytic gel had equally distribution of BiOBr nanosheets on the surface, and could be easily recycled from water. More strikingly, the gel could also rapidly kill all tested pathogenic bacteria (i. e., Escherichia coli, Pseudomonas aeruginosa, and Staphylococcus aureus) under irradiation. Its disinfection activity is attributed to remarkable intracellular ROS production and oxidative cell damage. Furthermore, the gel had higher photocatalytic activity than BiOBr nanosheets alone during degradation of organic dyes. This study developed a novel strategy for preparation of easy-recycling and high-efficiency photocatalytic systems for practical application in environmental treatment and medicinal disinfection. 相似文献
999.
Jun Feng YanLin Ye Biao Yang ChengJian Lin HuiMin Jia DanYang Pang ZhiHuan Li JianLing Lou QiTe Li XiaoFei Yang Jing Li HongLiang Zang Qiang Liu Wei Jiang ChenGuang Li Yang Liu ZhiQiang Chen HongYi Wu ChunGuang Wang Wei Liu Xiang Wang JingJing Li DiWen Luo Ying Jiang ShiWei Bai JinYan Xu NanRu Ma LiJie Sun DongXi Wang 《中国科学:物理学 力学 天文学(英文版)》2019,(1)
The inelastic excitations and cluster decay of ~(13)C have been measured using the reaction,9Be(~(13)C, ~(13)C* →~9Be + α)~9Be. We observe strong excitation to the 14.3-MeV(1/2-) resonant state from the cluster-decay channel, leading to an enhanced monopole matrix element of(6.3 ± 0.6) fm~2. This large cluster-related monopole strength is a clear indication of the cluster-structure domination of this state and is consistent with the recent prediction of the orthogonality condition model(OCM). It would be interesting to further explore the three-center molecular rotational band that is initiated from the observed band-head. 相似文献
1000.