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switchable slow light rainbow trapping and releasing in strongly coupling topological photonic systems

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Photonics Research 2019年第9期7卷 1075-1080页

作者： JIANFENG CHEN WENYAO LIANG ZHI-YUAN LI School of Physics and Optoelectronics South China University of Technology

We design and present a switchable slow light rainbow trapping(SLRT) state in a strongly coupling topological photonic system made from a magneto-optical photonic crystal waveguide channel. The waveguide channel supports slow light states with extremely small group velocity(vg2.1 × 10-6c), low group-velocity dispersion, and a broadband operation bandwidth(3.60–4.48 GHz, near 22% of bandwidth). These slow light states originate from the strong coupling between two counter propagating topological photonic states. Under a gradient magnetic field, different frequency components of a wave packet are separated and stored at different positions for a long temporal duration with high spatial precision(without crosstalk and overlap between the electric fields of different frequencies) to form SLRT. Besides, these SLRT states can be easily switched among the forbidden state,trapped state, and releasing state by tuning the external magnetic field. The results suggest that the topological photonic state can offer a precise route of spatial-temporal-spectral control upon a light signal and find applications for optical buffers, broadband slow light systems, optical filters, wavelength-division multiplexing, and other optical communication devices.

关键词： pro PC switchable slow light rainbow trapping and releasing in strongly coupling topological photonic systems

switchable terahertz polarization converter based on VO_(2)metamaterial

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Chinese Physics B 2022年第6期31卷 403-409页

作者：杜皓天江明珠曾丽珍张隆辉徐卫林张小文胡放荣 Guangxi Key Laboratory of Automatic Detecting Technology and Instrument Guilin University of Electronic TechnologyGuilin 541004China Guilin Institute of Information Technology Guilin 541004China

A switchable terahertz(THz)polarization converter based on vanadium dioxide(VO_(2)) metamaterial is *** is a 5-layer structure which containing metal split-ring-resonator(SRR),the first polyimide(PI)spacer,VO_(2) film,the second PI spacer,and metal *** is an array structure and the period in x and y directions is 100μ*** performance is simulated by using finite integration *** simulation results show that,when the VO_(2) is in insulating state,the device is a transmission polarization *** cross-linear polarization conversion can be realized in a broadband of0.70 THz,and the polarization conversion rate(PCR)is higher than 99%.Under thermal stimulus,the VO_(2) changes from insulating state to metallic state,and the device is a reflective polarization *** linear-to-circular polarization conversion can be successfully realized in a broadband of 0.50 THz,and the PCR is higher than 88%.

关键词： switchable terahertz(THz)metamaterial polarization conversion vanadium dioxide(VO_(2))

switchable hydrophobic-hydrophilic layer obtained onto porous alumina by plasma-enhanced fluorination

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Science China(Technological Sciences) 2009年第1期52卷 104-110页

作者： A. TRESSAUD C. LABRUGèRE E. DURAND C. BRIGOULEIX H. ANDRIESSEN Institute of Condensed Matter Chemistry of Bordeaux (ICMCB-CNRS) University Bordeaux 1 87 Avenue du Dr. A. Schweitzer AGFA GEVAERT NV Septestraat 27

Conventional lithographic printing processes using porous alumina for offset applications generally use "wet" routes. Recently "dry" processes have been developed which are based on a heat-induced hydrophilic/oleophilic conversion of one or more layers of the coating so that a stronger affinity to-wards ink or water fountain is created at the exposed areas with respect to the surface of the unex-posed coating. Treatments involving rf plasma-enhanced fluorination (PEF) constitute exceptional tools for modifying the surface properties of materials. Many advantages of these techniques can be indeed outlined, when compared to more conventional methods: room-temperature reactions, chemical modi-fications limited to surface only without changing the bulk properties, possible non-equilibrium reac-tions. The influence of PEF treatments on porous alumina layer used in printing plates has been tested with various fluorinated gases (CF4, C3F8 and C4F8) and characterized by XPS. The hydrophobic prop-erties of the fluorinated layer have been deduced from contact angle measurements. Using C4F8 rf-PEF treatment, the outmost surface of the hydrophilic alumina substrate used for lithographic printing is hydrophobized, or in other words, the hydrophilic substrate is converted into a support with hydro-phobic properties. Once being hydrophobized, the surface layer may be rendered hydrophilic using a heat pulse, thus giving rise to switchable hydrophobic-hydrophilic properties of the material.

关键词： porous alumina rf-plasma fluorination offset applications hydrophobic-hydrophilic switchable layer XPS contact angle

Proposal for All-Optical switchable and Tunable Ultrawideband Monocycle Generation Utilizing SOA Wavelength Conversion and Time Delay

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Photonic Sensors 2017年第1期7卷 66-71页

作者： Zhefeng HU Jianhui XU Min HOU Key Laboratory of Optical Fiber Sensing & Communications (Ministry of Education) School of Communication andInformation Engineering University of Electronic Science and Technology of China Chengdu 611731 China

An all-optical ultrawideband monocycle generator based on wavelength conversion in a semiconductor optical amplifier （SOA） and optical tunable delay in an optical delay line （ODL） is proposed and simulated. The system achieves optically switchable in pulse polarity and tunable in both the pulsewidth and radio frequency （RF） spectrum.

关键词： Microwave photonics ultrawideband (UWB) tunable switchable semiconductor optical amplifier(SOA) tunable time delay

switchable carbamate coagulants to improve recycling ionic liquid from biomass solutions

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Green Chemical Engineering 2021年第4期2卷 384-391页

作者： Julia L.Shamshina Ying Qin Ken Belmore Daniel T.Daly Robin D.Rogers Fiber and Biopolymer Research Institute Department of Plant and Soil ScienceTexas Tech UniversityLubbockTX79409USA Alabama Institute for Manufacturing Excellence The University of AlabamaTuscaloosaAL35487USA Department of Chemistry and Biochemistry The University of AlabamaTuscaloosaAL35487USA College of Arts&Sciences The University of AlabamaTuscaloosaAL35487USA Solutions Inc.P.O.Box 2206TuscaloosaAL35403USA

A reversible amine-carbamate approach has been developed to reduce the use of antisolvents such as water in the coagulation of biopolymers from ionic liquid(IL)solution and thus improve the economy of IL *** and chitin were recovered from 1-ethyl-3-methylimidazolium acetate([C_(2)mim][OAc])solution by introducing the miscible amines triethanolamine(TEA),ethylenediamine(EDA),or butylamine(BA)and bubbling CO_(2) at 40℃ and atmospheric pressure through the solutions to form carbamate salts in situ which resulted in biopolymer *** gave the best results because of its low boiling point and low viscosity,which benefited both biopolymer recovery and IL *** films and fibers could be formed by extrusion of an MCC/[C_(2)mim]-[OAc]solution into a coagulating bath comprised of a 1:1 M mixture of[C_(2)mim][OAc]and butylammonium butylcarbamate(BA-carbamate).The cellulose,IL,amine,and CO_(2) were easily separated,although the cellulose recovered required some water washings to remove traces of *** to 96.4%of the[C_(2)mim][OAc]could be recovered,76.2%from the coagulation bath and 20.2%from the water *** recycled IL was suitable for another cycle of cellulose dissolution and extrusion and 84.6%of the IL used for the second cycle was *** further work is needed,not the least of which will be reducing the amount of water needed for washing steps,some promising features of this process point the way for new directions for more economically viable IL recycling processes in biomass treatment with ILs.

关键词： Carbamate Ionic liquid Recovery switchable Coagulation Biopolymers Carbamates IL recycle

Theoretical demonstration of all-optical switchable and tunable UWB doublet pulse train generator utilizing SOA wavelength conversion and tunable time delay

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Frontiers of Optoelectronics 2017年第2期10卷 180-188页

作者： Zhefeng HU Jianhui XU Min HOU School of Communication and Information Engineering University of Electronic Science and Technology of China Chengdu 611731 China

An all-optical ultrawide band （UWB） doublet pulse train signal generator is proposed and theoretically simulated by utilizing an inverse wavelength conversion base on the cross-gain modulation （XGM） effect in a semiconductor optical amplifier （SOA） and controllable time delay in two optical delay lines （ODLs）. The proposed scheme is not only optically switchable in the polarity of pulse by switching the polarity of input pulse but also tunable in signal pulse width and radiofrequency （RF） spectrum by tuning the ODLs.

关键词： microwave photonics ultrawide band(UWB) tunable switchable semiconductor optical ampli-fier (SOA) tunable time delay

Phosphine-Catalyzed Interrupted Morita-Baylis-Hillman Reaction and switchable Domino Reactions of a-Substituted Activated Olefins with Formaldehyde and Mechanism Elucidation

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Chinese Journal of Chemistry 2019年第2期37卷 155-160页

作者： Jing Gu Ben-Xian Xiao Qin Ouyang Wei Du Ying-Chun Chen Key Laboratory of Drug-Targeting and Drug Delivery System of the Ministry of Education and Sichuan Research Center for Drug Precision Industrial Technology West China School of PharmacySichuan UniversityChengdu 610041China College of Pharmacy Third Military Medical UniversityShapingbaChongqing 400038China

Summary of main observation and conclusion 3-Olefinic oxindoles can undergo interrupted Morita-Baylis-Hillman reaction with formaldehyde. Apart from the previous reported dephosphoration to access reductive aldol-type products, here we uncovered that completely different pathways were followed by tuning the substitutions of 3-olefinic oxin doles. In com bin ation with formalin, an unexpected domino phosphorus-ylide formation, aldol-type addition, hemeacetal formation and O-substitution process was observed to produce 1,3-dioxolane derivatives. Moreover, a switchable sequence to produce formate derivatives via a key hydride transfer process was furnished by simply replacing formalin with paraformaldehyde. Density functional theory calculations were conducted to well elucidate the catalytic reaction mechanism.

关键词： Phosphine-Catalyzed Interrupted Morita-Baylis-Hillman Reaction switchable Domino Reactions of a-Substituted Activated Olefins Formaldehyde Mechanism Elucidation

Complexation of Triptycene-Derived Macrotricyclic Host with Bisparaquat Derivative and Self-Folding Guest： A switchable Process Controlled by K＋ Ions

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Chinese Journal of Chemistry 2013年第5期31卷 607-611页

作者： Ying Han Jiabin Guo Jing Cao Chuanfeng Chen Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and Function Institute of Chemistry Chinese Academy of Sciences Beijing 100190 China University of Chinese Academy of Sciences Beijing 100049 China

Triptycene-derived cylindrical macrotricyclic host with two dibenzo-30-crown-lO cavities could form stable 1 ： 1 complexes with not only polyether linked bisparaquat derivative but also a self-folding A-D-A guest in solu- tion and/or solid state. Moreover, it was found that switchable processes between the host and both the bisparaquat derivative and the self-folding guest could be further controlled by potassium ions.

关键词： complexation macrotricyclic host paraquat triptycene switchable

Complexation of Triptycene-Derived Macrotricyclic Host Containing Pyridine Groups with Paraquat Derivatives: A switchable Process Controlled by Zn^(2+) Ions

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Chinese Journal of Chemistry 2014年第8期32卷 721-726页

作者： Ying Han Jiabin Guo Chuanfeng Chen Beijing National Laboratory for Molecular Sciences CAS Key Laboratory of Molecular Recognition and FunctionInstitute of ChemistryChinese Academy of SciencesBeijing 100190China

A triptycene-derived macrotricyclic host containing two pyridine groups was synthesized,and it could form 1∶1 stable host-guest complexes with paraquat derivatives in both solution and solid ***,it was also found tha... 详细信息

关键词： triptycene macrotricyclic host paraquat switchable zinc ions