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Optical devices based on multilayer optical waveguide

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Frontiers of Optoelectronics 2013年第2期6卷 146-152页

作者： Sijun WENG, Li PEI Li PEI Ruifeng ZHAO Junjie YANG Yiqun WANG key lab of All Optical Network and advanced Telecommunication Network of EMC Beijing Jiaotong University Beijing 100044 China

Optical waveguide is used to guide the transmission of light. This paper reviews multilayer optical waveguide and some devices based on it. The optical waveguide can be divided into single-layer and multilayer optical waveguides in general. Here, multilayer cylindrical waveguide and multilayer planar waveguides were mainly focused. The analyzing method and the structures of waveguides were also demonstrated in briefly. Both these multilayer optical waveguide used in different kinds of optical devices including optical modulator, laser, optical amplifier, optical switch and special fiber were further presented. At last, the principle and structure of these multilayer optical devices were compared.

关键词： multilayer waveguide optical devices multi- layer structure

Characteristics Analysis of Condensation outside Horizontal Tube Bundles and Novel Condensation Enhancement Method

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Journal of Thermal Science 2022年第3期31卷 934-945页

作者： LI Nianqi TIAN Ke KE Hanbing ZENG Min WANG Qiuwang key laboratory of Thermo-Fluid Science and Engineering Ministry of EducationXi’an Jiaotong UniversityXi’an710049China key lab on Steam Power System Wuhan Second Ship Design and Research InstituteWuhan430025China

Condensation is a phase-change heat-transfer phenomenon crucial in many industries involving latent heat release and mass ***-and-tube condensers are essential contributors to the condensation process,and their tube bundles serve as a ***,the thermal-hydraulic characteristics of condensation in a longitudinal-flow shell-and-tube condenser were investigated *** shell-side longitudinal-flow condensation on the horizontal tube bundles was studied considering inlet flow rate,overheating temperature,and non-condensable *** pressure drops and heat transfer coefficients were subdivided into several components to provide further ***-phase interface behavior analyses were conducted to demonstrate the outcomes with respect to the non-condensable gas layer,vapor quality,and non-condensable gas *** on the thorough quantitative analyses outlined above,the thermal resistance of the condensation on the horizontal tube bundle was *** thermal resistance outside the tube was found to dominate the condensation ***,hexagon clamping baffles(HCBs)were introduced as a novel solution to impair condensate boundary layers and provide perturbations to intensify condensation heat *** results revealed that the HCBs enhanced the total heat transfer coefficients by 8.1%–40.7%while reducing the critical overheating temperature and the threshold ratio between sensible and latent heat.

关键词： shell-and-tube condenser film condensation non-condensable gas thermal resistance analysis

Transmission characteristics of Tomato chlorosis virus (ToCV) by Bemisia tabaci MED and its effects on host preference of vector whitefly

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Journal of Integrative Agriculture 2019年第9期18卷 2107-2114页

作者： WEI Ke-ke LI Jie DING Tian-bo LIU Tong-xian CHU Dong key lab of Integrated Crop Pest Management of Shandong Province College of Plant Health and Medicine Qingdao Agricultural University

The epidemiology of Tomato chlorosis virus(ToCV)in China is closely associated with its vector whitefly,Bemisia tabaci(Gennadius)***,the transmission characteristics of ToCV by *** MED remain poorly *** this study,we analyzed:1)the horizontal and vertical transmission of ToCV by *** MED whiteflies;2)the acquisition of ToCV by male and female *** MED whiteflies after different feeding durations;3)the transmission efficacy of viruliferous male and female *** MED whiteflies after different inoculation access periods(IAPs);4)the retention of ToCV by viruliferous male and female *** MED whiteflies after a 48 h acquisition access period(AAP);and 5)the effects of ToCV on host choice of healthy or ToCV-infected tomato plant of viruliferous and non-viruliferous *** MED at different time *** results showed that:1)viruliferous males could not transfer ToCV to non-viruliferous females,and vice versa,viruliferous females could not pass on ToCV to non-viruliferous *** could not be detected in the F1 generation adults;2)ToCV could be detected within 4.0%of females or males after a 20 min AAP;3)ToCV could be detected in 33.3%of tomato plants inoculated by 10 viruliferous males or females with IAPs of 20 or 30 min;4)the maximum retention time in females was 7 and 5 days in males;and 5)non-viruliferous *** MED did not show a preference for ToCV-infected tomato plants or healthy tomato ***,viruliferous *** MED whiteflies did prefer to settle on healthy tomato plants over ToCV-infected tomato *** findings will be helpful to better understand the epidemiology of the recently emerged plant virus,ToCV,in tomato fields in China.

关键词： Tomato chlorosis virus Bemisia tabaci MED transmission characteristics preference

Effects of Paranosema locustae(Microsporidia) on the development and morphological phase transformation of Locusta migratoria(Orthoptera: Acrididae) through modulation of the neurotransmitter taurine

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Journal of Integrative Agriculture 2020年第1期19卷 204-210页

作者： LI Ao-mei YIN Yue ZHANG Yu-xin ZHANG Liu ZHANG Kai-qi SHEN Jie TAN Shu-qian SHI Wang-peng Department of Entomology and MOA key lab of Pest Monitoring and Green Management College of Plant ProtectionChina Agricultural University

Neurotransmitters are important in the maintenance of phase transformation of Locusta migratoria(Arthropoda: Orthoptera). Here, the effects of the entomopathogen Paranosema locustae on the neurotransmitter taurine in migratory locusts were studied using biochemical methods. After inoculation with P. locustae, the taurine content of infected locusts significantly declined, but F/C values(ratio between the length of hind femur and the width of the head of locust) increased significantly, compared to healthy locusts. Meanwhile, F/C values of infected locusts that were injected with 2 μg of taurine showed no significant differences from those of healthy locusts, demonstrating that supplemental taurine inhibited the changes in morphological phase caused by P. locustae. Paranosema locustae infection also caused longer developmental durations and lower body weights of locusts, but these changes were unaffected after injection with taurine. These results provided new insights into the mechanisms by which microsporidian parasites affected their locust hosts.

关键词： Locusta migratoria Paranosema locustae neurotransmitter taurine morphological characteristics

A novel adaptive spectrum forming filter:Application in cognitive ultra-wideband

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Science China(Information Sciences) 2010年第12期53卷 2584-2599页

作者： LI Bin ,ZHOU Zheng & ZOU WeiXia key lab of Universal Wireless Communications,MOE.Wireless Network lab,Beijing University of Posts and Telecommunications,Beijing 100876,China 1. key lab of Universal Wireless Communications MOE. Wireless Network Lab Beijing University of Posts and Telecommunications Beijing 100876 China

Ultra wideband impulse radio(UWB-IR) has important applications in high data rate communications,high precision positioning and penetrating target *** with cognitive radio(CR),UWB can also greatly alleviate the current spectrum ***,the existing UWB waveforms are faced with two *** spectrum utilization of UWB signal is rather low,which reduces the communication ***,it appears difficult for UWB-IR to avoid spectrum collision with other incumbent *** UWB will inevitably interfere other legal wireless *** by these considerations,we model the UWB waveform design into an interpolation *** on radial basis function neural network,a novel UWB pulse is presented in this *** UWB pulse is then realized though reasonable simplification on the already proposed theoretical *** designed UWB pulses can adaptively track the external spectral environment where UWB devices work and reconfigure its emission spectrum according to the state of primer users without any modification on *** frequency utilization is maximized when there is no active primary *** adequate spectrum avoidance has also been achieved without much spectrum utilization degradation within the non-primary *** and analysis show that our UWB-IR pulse is much superior to the other existing UWB signals in the frequency utilization,spectrum avoidance and in the transmission performance.

关键词： UWB-IR cognitive radio pulse design RBF network spectrum efficiency spectrum avoidance

Theoretical Studies on the Fe-M Interactions and 31p NMR in Fe（CO）3（EtPhPpy）2MX2 （X=NCS, SCN, CI; M=Zn, Cd, Hg）

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Chinese Journal of Chemical Physics 2008年第5期21卷 438-444页

作者： Xiao-xuan Huang Xuan Xu Mei-xiang Xie School of Chemistry and Environment Key Lab of Technology on Electrochemical Energy Storage and Power Generation in Guangdong Universities South China Normal University Guangzhou 510006 China

To study the Fe-M interactions and their effects on 31p NMR, the structures of Fe（CO）3（EtPhPpy）2 1, Fe（CO）3（EtPhPpy）2M（NCS）2 （2： M=Zn, 3： M=Cd, 4： M=Hg） and Fe（CO）3（EtPhPpy）2CdX2 （5： X=C1, 6： X=SCN） were investigated by density functional theory （DFT） PBE0 method. The stabilities S of complexes follow S（2）〉S（3）〉S（4） and S（3）,.~S（6）〉S（5）, indicating that 6 is stable and may be synthesized. The complexes with thiocyanate are more stable than that with chloride in Fe（CO）3（EtPhPpy）2CdX2. The strength I of Fe-M interactions follows I（2）≈I（3）〈I（4）. The Fe-Cd interactions of 3 and 6, which contain thiocyanate, are stronger than that of 5 with chloride. The charge-transfer, which enhances with the increasing of Fe-M interaction strength, comes from Et, Ph, py, CO groups towards P, Fe, and M atoms. Because the delocalization of thiocyanate disperses the charge of M2＋, the charge-transfer of the complexes with thiocyanate is stronger than that with chloride. There is a a-bond between Fe and Hg atoms in 4. However, in binuclear complexes except 4, the Fe-M interactions act as nFe→nM, σP-Fe→nM and σC-Fe→nM delocalization, and the N-M interactions mainly act as nN→nM delocalization. In binuclear complexes, due to the Fe→M interactions, the strong σFe--C→σ＊Fe--p or σFe-Hg→σ＊Fe--I2 delocalization and the charge-transfer, the electron density on P nucleus is increased, and thus upfield 31p chemical shifts are caused （compared with mononuclear complex 1）.

关键词： DFT 31p NMR Metal-metal interaction Nature bond orbital

Postbuckling behavior of 3D braided rectangular plates subjected to uniaxial compression and transverse loads in thermal environments

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Science China(Technological Sciences) 2014年第7期57卷 1439-1453页

作者： CHU GuoPing LI ZhiMin Shanghai key lab of Digital Manufacture for Thin-Walled Structures School of Mechanical Engineering Shanghai Jiao Tong University

Postbuckling behavior of the 3D braided rectangular plates subjected to uniaxial compression combined with transverse loads in thermal environments is *** on a micro-macro-mechanical model,a 3D braided composite may be treated as a cell system and the geometry of each cell is deeply dependent on its position in the cross-section of the *** material properties of the epoxy are expressed as a linear function of ***,linear and nonlinear temperature distributions through the thickness are *** lateral pressure(three types of transverse loads,*** uniform load;transverse patch load over a central area;and transverse sinusoidal load)is first converted into an initial deflection and the initial geometric imperfection of the plate is taken into *** governing equations are based on Reddy’s higher-order shear deformation plate theory with a von Kármán-type of kinematic *** cases of the in-plane boundary conditions are also taken into account.A perturbation technique is employed to determine buckling loads and postbuckling equilibrium paths of simply supported 3D braided rectangular *** results reveal that the temperature rise,geometric parameter,fiber volume fraction,braiding angle,the character of the in-plane boundary conditions and different types of initial transverse loads have a significant effect on the buckling and postbuckling behavior of the braided composite plates.

关键词： 3D braided composite plate higher-order shear deformation plate theory buckling postbuckling transverse loads thermal environment

Separation of acidic and basic proteins by capillary electrophoresis using gemini surfactants and gemini-capped nanoparticles as buffer additives

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Science China Chemistry 2009年第10期52卷 1666-1676页

作者： LIU Qian LI YanQing YANG YanMin YAO ShouZhuo State key lab of Chemo/Biosensing and Chemometrics College of Chemistry and Chemical EngineeringHunan UniversityChangsha 410082China

This paper demonstrated simultaneous separation of acidic and basic proteins using cationic gemini surfactants as buffer additives in capillary electrophoresis. We showed that even at a low concentration (0.1 mmol·L-1) of alkanediyl-α,ω-bis(dimethyloctadecylammonium bromide) (18-s-18), the wall adsorption of both acidic and basic proteins could be effectively suppressed under acidic conditions. Smaller micelle size (e.g., s=5-8) is more effective for the separation of acidic proteins than larger micelle size (e.g., s10). Varying the spacer length of gemini surfactants can influence the electrophoretic mobility and selectivity of proteins to achieve the desired separation. Under the optimized conditions, RSDs of the migration time were less than 0.8% and 2.2% for run-to-run and day-to-day assays, respectively, and protein recoveries ranged from 79% to 100.4%. Furthermore, we also investigated the use of gemini surfactant-capped gold nanoparticles (gemini@AuNPs) as buffer additives in protein separation. Introduction of AuNPs into the buffer shortened the analysis time and slightly improved the separation efficiencies. Finally, we presented the applications of this method in the analysis of bio-logical samples, including plasma, red blood cells and egg white.

关键词： gemini surfactant protein separation capillary electrophoresis gold nanoparticle

Complex hexagonal close-packed dendritic growth during alloy solidification by graphics processing unit-accelerated three-dimensional phase-field simulations:demo for Mg–Gd alloy

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Rare Metals 2023年第10期42卷 3468-3484页

作者： Sheng-Lan Yang Jing Zhong Kai Wang Xun Kang Jian-Bao Gao Jiong Wang Qian Li Li-Jun Zhang State key lab of Powder Metallurgy Central South UniversityChangsha410083China Institute for Energy and Climate Research IEK-2Forschungszentrum Jülich52425JülichGermany International Center for materials Nanoarchitechonics(WPI-MANA) National Institute for Materials Science(NIMS)Ibaraki305-0044Japan Graduate School of Chemical Science and Engineering Hokkaido UniversitySapporo060-0808Japan National Engineering Research Center for Magnesium Alloys Chongqing UniversityChongqing400044China

In this study,insights into the effect of interfacial anisotropy on a complex hexagonal close-packed(hcp) dendritic growth during alloy solidification were gained by graphics processing unit(GPU)-accelerated three-dimensional(3D) phase-field simulations,as demonstrated for a Mg-Gd *** anisotropic phasefield model with finite interface dissipation was developed by incorporating the contribution of the anisotropy of interfacial energy into the total free energy *** modified spherical harmonic anisotropy function was then chosen for the hcp *** GPU parallel computing algorithm was implemented in the present phase-field model,and a corresponding code was developed in the compute unified device architecture parallel computing *** tests indicated that the calculation efficiency of a single TESLA V100 GPU could be~80times that of open multi-processing(OpenMP) with eight central processing unit *** coupling the phase-field model with reliable thermodynamic and interfacial energy descriptions,the 3D phase-field simulation of α-Mg dendritic growth in the Mg-6Gd(in wt%) alloy during solidification was *** two-dimensional dendrite morphologies were revealed by cutting the simulated 3D dendrite along different crystallographic *** sixfold equiaxed and butterflied microstructures observed in experiments were well reproduced.

关键词： Interfacial anisotropy Dendrite solidification Phase-field model Graphics processing unit(GPU) Mg–Gd