检索结果-南通市图书馆

Broadband and fabrication-tolerant 3-dB couplers with topological valley edge modes

在线全文

学校读者我要写书评

暂无评论

Light(Science & Applications) 2024年第8期13卷 1623-1630页

作者： Guo-Jing Tang Xiao-dong Chen Lu Sun Chao-Heng Guo Meng-Yu Li Zhong-Tao Tian Hou-Hong Chen Hong-Wei Wang Qi-Yao Sun Ying-Di Pan Xin-Tao He Yi-Kai Su jian-wen dong School of Physics&State Key Laboratory of Optoelectronic Materials and Technologies Sun Yat-sen UniversityGuangzhou 510275China State Key Laboratory of Advanced Optical Communication Systems and Networks Department of Electronic EngineeringShanghai Jiao Tong UniversityShanghai 200240China

3-dB couplers,which are commonly used in photonic integrated circuits for on-chip information processing,precision measurement,and quantum computing,face challenges in achieving robust performance due to their limited 3-dB bandwidths and sensitivity to fabrication *** address this,we introduce topological physics to nanophotonics,developing a framework for topological 3-dB *** couplers exhibit broad working wavelength range and robustness against fabrication dimensional *** leveraging valley-Hall topology and mirror symmetry,the photonic-crystal-slab couplers achieve ideal 3-dB splitting characterized by a wavelength-insensitive scattering *** analysis confirms the superiority on broad bandwidth of 48 nm and robust splitting against dimensional errors of 20 *** further propose a topological interferometer for on-chip distance measurement,which also exhibits robustness against dimensional *** extension of topological principles to the fields of interferometers,may open up new possibilities for constructing robust wavelength division multiplexing,temperature-drift-insensitive sensing,and optical coherence tomography applications.

关键词： topological splitting insensitive

Constructed wetlands for wastewater treatment in cold climate--A review

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Journal of Environmental Sciences 2017年第7期29卷 293-311页

作者： Mo Wang dong Qing Zhang jian wen dong Soon Keat Tan College of Landscape Architecture Fujian Agriculture and Forestry UniversityFuzhou 350002China Nanyang Environment&Water Research Institute 1 CleanTech Loop#06-10637141Singapore School of Civil and Environmental Engineering Nanyang Technological University639798Singapore

Constructed wetlands（CWs） have been successfully used for treating various wastewaters for decades and have been identified as a sustainable wastewater management option ***,the application of CW for wastewater treatment in frigid climate presents special *** treatment of wastewater relies largely on biological processes,and reliable treatment is often a function of climate *** date,the rate of adoption of wetland technology for wastewater treatment in cold regions has been slow and there are relatively few published reports on CW applications in cold *** paper therefore highlights the practice and applications of treatment wetlands in cold climate.A comprehensive review of the effectiveness of contaminant removal in different wetland systems including：（1） free water surface（FWS） CWs;（2） subsurface flow（SSF） CWs;and（3） hybrid wetland systems,is *** emphasis of this review is also placed on the influence of cold weather conditions on the removal efficacies of different *** strategies of wetland design and operation for performance intensification,such as the presence of plant,operational mode,effluent recirculation,artificial aeration and in-series design,which are crucial to achieve the sustainable treatment performance in cold climate,are also *** study is conducive to further research for the understanding of CW design and treatment performance in cold climate.

关键词： Constructed wetlands Wastewater treatment Nutrient Cold climate

Dual-polarization two-dimensional valley photonic crystals

在线全文

学校读者我要写书评

暂无评论

Science China(Physics,Mechanics & Astronomy) 2022年第8期65卷 102-109页

作者： Xin-Tao He jian-Wei Liu Fu-Long Shi Ke Shen wen-Jie Chen Xiao-dong Chen jian-wen dong School of Physics State Key Laboratory of Optoelectronic Materials and TechnologiesSun Yat-sen UniversityGuangzhou510275China

The recent realization of valley physics in photonic systems has enriched the topological phases of light with protected edge modes and shown applications in designing high-performance photonic devices. However, the widely reported valley Hall effect of light in two-dimensional systems is limited to one single polarization. Here, we present dual-polarization two-dimensional valley photonic crystals by simultaneously opening two frequency accidental degenerate Dirac cones. Two band gaps with different polarizations are characterized by opposite-valley Chern numbers, which are confirmed by the opposite-phase vortex distributions of bulk modes and opposite Berry curvatures. This situation results in the polarization-dependent refraction of bulk and edge modes, which locate in opposite valleys. The polarization-independent topological valley transport is also demonstrated. Our work shows the flexible control of light in topological photonic systems with a polarization degree of freedom and has applications in polarization multiplexing photonic devices.

关键词： topological photonics valley photonic crystals polarization

Second Chern crystals with inherently non-trivial topology

在线全文

学校读者我要写书评

暂无评论

National Science Review 2023年第8期10卷 148-155页

作者： Xiao-dong Chen Fu-Long Shi jian-Wei Liu Ke Shen Xin-Tao He C.T. Chan wen-Jie Chen jian-wen dong School of Physics and State Key Laboratory of Optoelectronic Materials and Technologies Sun Yat-sen University Department of Physics The Hong Kong University of Science and Technology

Chern insulators have been generalized to many classical wave systems and thereby lead to many potential applications such as robust waveguides, quantum computation and high-performance lasers. However, the band structure of a material can be either topologically trivial or non-trivial, depending on how the crystal structure is designed. Here, we propose a second Chern crystal in a four-dimensional parameter space by introducing two extra synthetic translation dimensions. Since the topology of the bulk bands in the synthetic translation space is intrinsically non-trivial, our proposed four-dimensional crystal is guaranteed to be topologically non-trivial regardless of the crystal’s detailed configuration. We derive the topologically protected modes on the lower dimensional boundaries of such a crystal via dimension ***, we observe the one-dimensional gapless dislocation modes and confirm their robustness in experiments. Our findings provide novel perspectives on topologically non-trivial crystals and may inspire designs of classical wave devices.

关键词： topological photonics synthetic dimension photonic crystals dislocation mode

Penetration performance of W/Cu double-layer shaped charge liners

在线全文

同方期刊数据库

学校读者我要写书评

暂无评论

Rare Metals 2016年第2期35卷 184-191页

作者： wen-jian dong Jin-Xu Liu Xing-Wang Cheng Shu-Kui Li Qing-He Zou wen-Qi Guo School of Materials Science and Engineering Beijing Institute of Technology Mudanjiang North Alloy Tool Co. Ltd.

Two kinds of W/Cu double-layer shaped charge liner（SCL） were prepared by chemical vapor deposition（CVD） combined with electroforming technique： A SCL with W inner layer and Cu outer layer, B SCL with Cu inner layer and W outer layer. The penetration properties of A and B SCLs were researched. The results show that the two SCLs can form continuous jet and the tip velocities of A and B jets are 7.4 and 6.3 km s^（-1）, respectively. The kinetic energy density（5.3 9 1011 J m-3） of A jet tip increases by 194.4 %compared with that（1.8 9 1011 J m-3） of B jet tip. B jet,however, exhibits deeper penetration depth at the same experimental conditions. The chemical component and microstructure of the area nearby the ballistic perforation were researched. Component analysis shows that both the jets are formed only from inner layer metal. Microstructure analysis shows that martensite and intermetallic form around ballistic perforation penetrated by A SCL due to the intensive interaction between W jet and steel target. The two kinds of newly formed ultrahard phases also hinder the jet from penetrating target further. As a result of relatively alleviative interaction between Cu jet and target, only solid solution rather than ultrahard phases forms around ballistic perforation penetrated by B SCL.

关键词： Shaped charge liner Jet Penetration performance Chemical vapor deposition Electroforming technique

Ideal nodal rings of one-dimensional photonic crystals in the visible region

在线全文

学校读者我要写书评

暂无评论

Light(Science & Applications) 2022年第6期11卷 1178-1185页

作者： Wei-Min Deng Ze-Ming Chen Meng-Yu Li Chao-Heng Guo Zhong-Tao Tian Ke-Xin Sun Xiao-dong Chen wen-Jie Chen jian-wen dong School of Physics&State Key Laboratory of Optoelectronic Materials and Technologies Sun Yat-sen University510275 GuangzhouChina

Three-dimensional(3D)artificial metacrystals host rich topological phases,such as Weyl points,nodal rings,and 3D photonic topological *** topological states enable a wide range of applications,including 3D robust waveguides,one-way fiber,and negative refraction of the surface ***,these carefully designed metacrystals are usually very complex,hindering their extension to nanoscale photonic ***,we theoretically proposed and experimentally realized an ideal nodal ring in the visible region using a simple 1D photonic *** TT-Berrry phase around the ring is manifested by a 2π reflection phase's winding and the resultant drumhead surface *** breaking the inversion symmetry,the nodal ring can be gapped and the n-Berry phase would diffuse into a toroidal-shaped Berry flux,resulting in photonic ridge states(the 3D extension of quantum valley Hall states).Our results provide a simple and feasible platform for exploring 3D topological physics and its potential applications in nanophotonics.

关键词： topological nodal visible

Construction of mTNFR1shRNA Plasmid and its Biological Effects on MHV-3 Induced Fulminant Hepatitis in BALB/cJ Mice

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Virologica Sinica 2010年第1期25卷 52-58页

作者： Sui GAO Ming WANG jian-wen GUO dong Xi Xiao-ping LUO Qin NING Laboratory of Infectious Immunology Tongji Hospital of Tongji Medical College Huazhong University of Science and Technology Wuhan 430030 China

Previous study on TNFRl-mediated hepatocyte apoptosis has been implicated in the development of fulminant viral hepatitis. To interfere with the potentially effective target, plasmid named p-mTNFRlshRNA complimentary to the sequence responsible for mTNFR1 was also constructed and further confirmed by sequence analysis. To investigate the effect of mTNFRlshRNA plasmid on mTNFR1 expression in vivo and the disease progress in MHV-3 induced fulminant hepatitis mice model. By hydrodynamic injection of mTNFRlshRNA plasmid, the survival rate of mice, hepatic pathological change were examined and compared between mice with/without mTNFRlshRNA plasmid intervention. The expression of mTNFR1 was detected by Real-time PCR, immunohistochemistry staining. The mTNFRlshRNA plasmid significantly reduced mTNFR1 expression in vivo, markedly ameliorates inflammatory infiltration, prolonged the survival time period and elevated the survival rate from 0 up to 13.3% in Balb/cJ mice with MHV-3 induced fulminant hepatitis. This study was designed to explore the opportunity of RNA interference technique in inhibiting TNFR1 expression, which has been reported to be involved in the development of a variety of diseases including fulminant viral hepatitis and severe chronic hepatitis B.

关键词： Fulminant hepatitis TNFR1 RNA interference shRNA

Phase characterisation of metalenses

在线全文

学校读者我要写书评

暂无评论

Light(Science & Applications) 2021年第4期10卷 551-561页

作者： Maoxiong Zhao Mu Ku Chen Ze-Peng Zhuang Yiwen Zhang Ang Chen Qinmiao Chen wenzhe Liu Jiajun Wang Ze-Ming Chen Bo Wang Xiaohan Liu Haiwei Yin Shumin Xiao Lei Shi jian-wen dong jian Zi Din Ping Tsai State Key Laboratory of Surface Physics Key Laboratory of Micro-and Nano-Photonic Struaures(Ministry of Education)and Department of PhysicsFudan University200433 ShanghaiChina Department of Electronic and Information Engineering The Hong Kong Polytechnic University999077 Hong KongChina School of Physics and State Key Laboratory of Optoelectronic Materials and Technologies Sun Yat-sen University510275 GuangzhouChina Shanghai Engineering Research Center of Optical Metrology for Nanofabrication(SERCOM) 200433 ShanghaiChina State Key Laboratory on Tunable Laser Technology Ministry of Industry and Information Technology Key Lab of Micro-Nano Optoelectronic Information SystemShenzhen Graduate SchoolHarbin Institute of Technology518055 ShenzhenChina

Metalenses have emerged as a new optical element or system in recent years,showing superior performance and abundant ***,the phase distribution of a metalens has not been measured directly up to now,hindering further quantitative evaluation of its *** have developed an interferometric imaging phase measurement system to measure the phase distribution of a metalens by taking only one photo of the interference *** on the measured phase distribution,we analyse the negative chromatic aberration effect of monochromatic metalenses and propose a feature size of *** sensitivities of the phase response to wavelength between the Pancharatnam-Berry phase-based metalens and propagation phase-reliant metalens are directly observed in the ***,through phase distribution analysis,it is found that the distance between the measured metalens and the brightest spot of focusing will deviate from the focal length when the metalens has a low nominal numerical aperture,even though the metalens is ideal without any fabrication *** also use the measured phase distribution to quantitatively characterise the imaging performance of the *** phase measurement system will help not only designers optimise the designs of metalenses but also fabricants distinguish defects to improve the fabrication process,which will pave the way for metalenses in industrial applications.

关键词： character distribution nominal

Carbon nanofibers embedded with Fe-Co alloy nanoparticles via electrospinning as lightweight high-performance electromagnetic wave absorbers

维普期刊数据库评论

在线全文

维普期刊数据库

学校读者我要写书评

暂无评论

Rare Metals 2024年第6期43卷 2769-2783页

作者： wen-Jun Cai jian-Guo jiang Zi-dong Zhang Zi-Xuan Liu Lu-JieZhang Zhen-Kun Long Ke Bi Key Laboratory for Liquid-Solid Structural Evolution and Processing of Materials(Ministry of Education) Shandong UniversityJinan 250061China School of Materials Science and Engineering Shandong UniversityJinan 250061China Energy Institute Qilu University of Technology(Shandong Academy of Sciences)Jinan 250014China State Key Laboratory of Information Photonics and Optical Communications School of ScienceBeijing University of Posts and TelecommunicationsBeijing 100876China

As a lot of electromagnetic pollution and interference issues have emerged,to overcome electromagnetic interference,prevent electromagnetic hazards,and develop new high-performance electromagnetic wave(EMW)absorbers have become a significant task in the field of materials *** this paper,a three-dimensional(3D)carbon nanofibers network with core-shell structure,embedded with varied molar ratios of iron and cobalt(4:0,3:1,2:2,1:3,0:4),was effectively synthesized(Fe/Co@C-CNFs)via *** phase,microstructure,magnetic and EMW absorption properties were *** is discovered that Fe/Co@C-CNFs doped with iron:cobalt=1:1 have excellent EMW absorption *** the matching thickness is 1.08 mm,the minimum reflection loss(RL)value is-18.66 dB,while the maximum effective absorption bandwidth(EAB)reaches 4.2 GHz(13.9-18 GHz)at a thickness of 1.22 *** is owing to the absorbers'superior impedance matching and multiple reflections as well as the conductivity,dielectric,and magnetic losses of carbon nanofibers embedded with Fe-Co alloy *** addition,the radar cross section(RCS)of the absorbers has been calculated by CST Studio Suite,showing that the absorbing coating can effectively reduce the RCS at various angles,especially for Fe/Co@C-CNFs doped with iron:cobalt=1:*** findings not only provide new insights for the preparation of light-weight and high-performance electromagnetic wave absorbers,but also contribute to energy storage and conversion.

关键词： Electromagnetic wave(EMW)absorbers Fe/Co@C-CNFs Core-shell structure EMW absorbing mechanism Radar cross section(RCS)