scispace - formally typeset
Search or ask a question
Institution

Hengyang Normal University

EducationHengyang, China
About: Hengyang Normal University is a education organization based out in Hengyang, China. It is known for research contribution in the topics: Graphene & Adsorption. The organization has 1087 authors who have published 1280 publications receiving 13850 citations. The organization is also known as: Hengyang Teachers' College & Héngyáng Shīfàn Xuéyuàn.


Papers
More filters
Book ChapterDOI
06 Sep 2014
TL;DR: Experimental results demonstrate the effectiveness of SFV, and the combination of the traditional FV and SFV outperforms state-of-the-art methods on these datasets with a large margin.
Abstract: Representation of video is a vital problem in action recognition. This paper proposes Stacked Fisher Vectors (SFV), a new representation with multi-layer nested Fisher vector encoding, for action recognition. In the first layer, we densely sample large subvolumes from input videos, extract local features, and encode them using Fisher vectors (FVs). The second layer compresses the FVs of subvolumes obtained in previous layer, and then encodes them again with Fisher vectors. Compared with standard FV, SFV allows refining the representation and abstracting semantic information in a hierarchical way. Compared with recent mid-level based action representations, SFV need not to mine discriminative action parts but can preserve mid-level information through Fisher vector encoding in higher layer. We evaluate the proposed methods on three challenging datasets, namely Youtube, J-HMDB, and HMDB51. Experimental results demonstrate the effectiveness of SFV, and the combination of the traditional FV and SFV outperforms state-of-the-art methods on these datasets with a large margin.

404 citations

Journal ArticleDOI
TL;DR: This electrochemical sensor was further applied to determine 4-NP in real water samples, and it showed great promise for simple, sensitive, and quantitative detection of 4- NP.

399 citations

Journal ArticleDOI
TL;DR: A multifocus optical vortex metalens, with enhanced signal-to-noise ratio, is presented, which focuses three longitudinal vortices with distinct topological charges at different focal planes for circularly polarized light in a compact device.
Abstract: A multifocus optical vortex metalens, with enhanced signal-to-noise ratio, is presented, which focuses three longitudinal vortices with distinct topological charges at different focal planes. The design largely extends the flexibility of tuning the number of vortices and their focal positions for circularly polarized light in a compact device, which provides the convenience for the nanomanipulation of optical vortices.

384 citations

Journal ArticleDOI
TL;DR: A coupled redox dynamic that needs to be taken into account when designing high-capacity layered cathode materials for high-voltage lithium-ion batteries is unveiled.
Abstract: Surfaces, interfaces and grain boundaries are classically known to be sinks of defects generated within the bulk lattice. Here, we report an inverse case by which the defects generated at the particle surface are continuously pumped into the bulk lattice. We show that, during operation of a rechargeable battery, oxygen vacancies produced at the surfaces of lithium-rich layered cathode particles migrate towards the inside lattice. This process is associated with a high cutoff voltage at which an anionic redox process is activated. First-principle calculations reveal that triggering of this redox process leads to a sharp decrease of both the formation energy of oxygen vacancies and the migration barrier of oxidized oxide ions, therefore enabling the migration of oxygen vacancies into the bulk lattice of the cathode. This work unveils a coupled redox dynamic that needs to be taken into account when designing high-capacity layered cathode materials for high-voltage lithium-ion batteries.

277 citations

Journal ArticleDOI
TL;DR: In this article, a giant photonic spin Hall effect (SHE) was observed in a dielectric-based metamaterial with a spin-dependent splitting in momentum space.
Abstract: The photonic spin Hall effect (SHE) in the reflection and refraction at an interface is very weak because of the weak spin-orbit interaction. Here, we report the observation of a giant photonic SHE in a dielectric-based metamaterial. The metamaterial is structured to create a coordinate-dependent, geometric Pancharatnam–Berry phase that results in an SHE with a spin-dependent splitting in momentum space. It is unlike the SHE that occurs in real space in the reflection and refraction at an interface, which results from the momentum-dependent gradient of the geometric Rytov–Vladimirskii–Berry phase. We theorize a unified description of the photonic SHE based on the two types of geometric phase gradient, and we experimentally measure the giant spin-dependent shift of the beam centroid produced by the metamaterial at a visible wavelength. Our results suggest that the structured metamaterial offers a potential method of manipulating spin-polarized photons and the orbital angular momentum of light and thus enables applications in spin-controlled nanophotonics. A giant photonic spin Hall effect (SHE) has been predicted and experimentally observed in a dielectric metamaterial by scientists in China. The conventional SHE that occurs when light is reflected or refracted at an interface is inherently weak due to the weak spin–orbit interaction. Now, researchers at Hunan University, Hengyang Normal University and Shenzhen University have theoretically predicted and experimentally confirmed a giant SHE in a metamaterial structured to produce the Pancharatnam–Berry phase in one dimension and having a spatially varying birefringence. Unlike the tiny real-space shift induced by the Rytov–Vladimirskii–Berry phase gradient, the giant SHE occurs in momentum space and is sufficiently large to be observed directly. Such metamaterials could potentially be used to manipulate spin-polarized photons and the orbital angular momentum of light, enabling applications in spin-controlled nanophotonics.

233 citations


Authors

Showing all 1097 results

NameH-indexPapersCitations
Jian Liu117209073156
Jin-Heng Li442275749
He-Xiu Xu37933620
Wei Zhou351914238
Lixin Xiao331865300
Xiaohui Ling31903197
Junhua Li28772205
Shan Zou27912894
Xiaojiang Peng23732860
Ying Yan21691163
Zhifeng Xu21341490
Fulong Chen20721009
Zhifeng Yang20341923
Man-Sheng Chen20291568
Lei Wang191581466
Network Information
Related Institutions (5)
Hunan University
44.1K papers, 863.1K citations

79% related

South China Normal University
20.4K papers, 304K citations

78% related

Zhejiang Normal University
11.6K papers, 190.7K citations

78% related

Xiangtan University
12K papers, 184.3K citations

78% related

Nanjing Normal University
20.2K papers, 325K citations

78% related

Performance
Metrics
No. of papers from the Institution in previous years
YearPapers
20234
202227
2021145
2020175
2019116
2018102