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发光学报 2016年第2期37卷 224-229页

作者：曹小龙车永莉姚建铨山东科技大学机械电子工程学院山东青岛266590 天津大学精密仪器与光电子工程学院天津300072 光电信息技术教育部重点实验室(天津大学) 天津300072

为了实现基于光整流方式的室温下宽调谐高效率太赫兹源,设计了一种适于双波长CO2激光器共振子带跃迁泵浦的双阱嵌套形非对称量子阱结构,结构组分为Al0.5Ga0.5As/Ga As/Al0.2Ga0.8As,采用密度矩阵及迭代方法计算了其二阶非线性光整流系数... 详细信息

为了实现基于光整流方式的室温下宽调谐高效率太赫兹源,设计了一种适于双波长CO2激光器共振子带跃迁泵浦的双阱嵌套形非对称量子阱结构,结构组分为Al0.5Ga0.5As/Ga As/Al0.2Ga0.8As,采用密度矩阵及迭代方法计算了其二阶非线性光整流系数χo(2)表达式,在导带为抛物线形和非抛物线形两种条件下对χo(2)进行对比研究。计算结果表明,其偶极跃迁矩阵元随量子阱总阱宽的增大而逐渐减小。当固定量子阱总阱宽及其中一束泵浦光波长不变时,χo(2)随着另一束泵浦光波长的增加,呈现出先增大后减小的变化趋势。当深阱为7 nm、总阱宽为23 nm、两束泵浦光相等为10.64μm时,χo(2)达到最大值5.925×10-6m/V;随着总阱宽的增大,χo(2)曲线呈现"红移"现象,其原因为量子限制效应导致了不同阱宽条件下的量子阱能级值差不同,从而造成满足泵浦光光子能量与能级差共振条件的变化。导带为抛物线形和非抛物线形两种条件下的χo(2)的最大值对应泵浦光波长基本相同,χo(2)数值上的差异主要由跃迁矩阵元的不同导致。

关键词：光学整流子带跃迁非对称量子阱太赫兹波

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液晶电控调谐滤波器的研究

光子学报 2010年第5期39卷 789-791页

作者：任广军姚建铨天津大学精密仪器与光电子工程学院激光与光电子研究所天津300072 天津大学光电信息科学技术教育部重点实验室天津300072 天津理工大学电子信息工程学院天津300384 天津理工大学薄膜电子与通信器件天津市重点实验室天津300384

理论分析了液晶调谐滤波器的调谐原理,利用岛津UV-23101分光光度计,通过对BL-009型向列相液晶透射比的测试,分析了可见光波段液晶透射比随电场的变化情况,作出了入射光波长从400～800nm时液晶透射比随电压变化的关系曲线,并就氩离子激... 详细信息

理论分析了液晶调谐滤波器的调谐原理,利用岛津UV-23101分光光度计,通过对BL-009型向列相液晶透射比的测试,分析了可见光波段液晶透射比随电场的变化情况,作出了入射光波长从400～800nm时液晶透射比随电压变化的关系曲线,并就氩离子激光器两条谱线488nm和514.5nm进行了提取.

关键词：液晶电控滤波器

Influence of cutterhead opening ratio on soil arching effect and face stability during tunnelling through non-uniform soils

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Underground Space 2024年第4期17卷 45-59页

作者： Xue-jian Chen Pei-Pei Fang Qiu-Nan Chen Jun Hu Kai yao Yong Liu State Key Laboratory of Water Resources Engineering and Management Wuhan UniversityWuhan 430072China Hubei Technology Innovation Center for Smart Hydropower Wuhan 430000China College of Civil Engineering Anhui Jianzhu UniversityHefei 230601China School of Civil Engineering Hunan University of Science and TechnologyXiangtan 411201China School of Civil and Architectural Engineering Hainan UniversityHaikou 570228China School of Qilu Transportation Shandong UniversityJinan 250002China

Tunnelling has increasingly become an essential tool in the exploration of underground space.A typical construction problem is the face instability during tunnelling,posing a great threat to associated *** face instability often occurs with the soil arching *** study investigates the combined effect of cutterhead opening ratio and soil non-uniformity on soil arching effect and face stability,via conducting random finite-element analysis coupled with Monte–Carlo *** results underscore that the face stability is strongly associated with the evolution of stress *** obtained stability factors in the uniform soils can serve as a reference for the design of support pressure in practical tunnelling *** addition,non-uniform soils exhibit a lower stability factor than uniform soils,which implies that the latter likely yields an underestimated probability of face *** tunnel face is found to have a probability of failure more than 50%if the spatial non-uniformity of soil is *** the end,a practical framework is established to determine factor of safety(FOS)corresponding to different levels of probability of face failure considering various opening ratios in non-uniform *** required FOS is 1.70 to limit the probability of face instability no more than 0.1%.Our findings can facilitate the prediction of probability of instability in the conventionally deterministic design of face pressure.

关键词： Tunnel Face stability Soil arching effect Cutterhead opening ratio Non-uniform soil Random field

Magnesium-containing pellet regulating blast furnace ferrous burden interaction:softening-melting behavior and mechanism

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Journal of Iron and Steel Research International 2024年第7期31卷 1623-1635页

作者： Li-ming Ma jian-liang Zhang yao-zu Wang Xiao-yong Ma Gui-lin Wang Zhuo Li Hui-qing jiang Zheng-jian Liu School of Metallurgical and Ecological Engineering University of Science and Technology BeijingBeijing 100083China School of Intelligence Science and Technology University of Science and Technology BeijingBeijing 100083China Lingyuan Iron and Steel Group Co. Lingyuan 122500LiaoningChina

MgO participates in all stages of sintering,pelletizing,and blast furnace ironmaking,and synergistically optimizing the distribution of MgO in ferrous burden can effectively enhance the interaction within the ferrous burdens and optimize the softening-melting properties of the mixed ***-containing pellets mixed with low-MgO sinter or mixed with high-MgO sinter in the blast furnace ferrous burden structure have opposite softening-melting performance *** the structure of the ferrous burden is magnesium-containing pellets mixed with low-MgO sinter,the magnesium-containing pellets can enhance the interaction of the ferrous burden in the process of softening-melting,which can optimize the composition of the slag phase and improve the slag *** the structure of the ferrous burden is magnesium-containing pellets mixed with high-MgO sinter,the magnesium-containing pellets weaken the interaction of the ferrous burden in the process of softening-melting,increase the content of the high melting point solid-phase particles in the slag,lead to an increase in the viscosity of the slag and difficult separation of the slag and iron,and decrease the permeability of the charge ***,to ensure good permeability of the mixed burden,the following measures are suggested:optimizing the MgO distribution of the ferrous burden,reducing the MgO content of the sinter to 1.96 wt.%,increasing the MgO content of the pellets to 1.03-1.30 wt.%,controlling the MgO/Al_(2)O_(3) ratio of the mixed burden within 1.15-1.32,narrowing the position of the cohesive zone,and maintaining an S value(permeability index)of approximately 150 kPa℃.

关键词： Ironmaking Ferrous burden Softening-melting property Interaction Permeability Slag

重复频率1.2GHz皮秒脉冲全光纤掺镱激光器

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光子学报 2019年第11期48卷 162-169页

作者：韦小乐魏淮盛泉付士杰史伟姚建铨天津大学精密仪器与光电子工程学院激光与光电子研究所天津300072 天津大学光电信息技术教育部重点实验室天津300072 北京交通大学电子信息工程学院北京100044 亚利桑那大学光学科学学院美国亚利桑那州85721

研究实现了基于半导体可饱和吸收体被动锁模的高重频全光纤掺镱皮秒脉冲激光器.种子源采取环形腔结构,当抽运功率为112 mW时,获得了稳定的锁模脉冲激光,其中心波长为1064.1 nm,3 dB谱宽为3.6 nm,脉冲宽度为4.2 ps,重复频率为19.2 MHz.... 详细信息

研究实现了基于半导体可饱和吸收体被动锁模的高重频全光纤掺镱皮秒脉冲激光器.种子源采取环形腔结构,当抽运功率为112 mW时,获得了稳定的锁模脉冲激光,其中心波长为1064.1 nm,3 dB谱宽为3.6 nm,脉冲宽度为4.2 ps,重复频率为19.2 MHz.受限于谐振腔长度,光纤激光器重复频率很难得到进一步提高.因此设计并搭建了一种基于分束器和延时光纤的全新低损耗高重频脉冲调制器,将种子激光重复频率提高到1.2 GHz.该设计有效降低了脉冲在耦合过程中的能量损耗,为提高全光纤超短脉冲激光器重复频率提供了新途径.

关键词：掺镱光纤激光器被动锁模高重频脉冲调制器超短脉冲耗散孤子

A novel method for extracting and optimizing the complex permittivity of paper-based composites based on an artificial neural network model

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Science China Technological Sciences 2024年第10期67卷 3190-3204页

作者： XIA ChenBin SHEN JunYi LIAO ShaoWei WANG Yi HUANG ZhengSheng XUE quan TANG Min LONG Jin HU jian School of Light Industry and Engineering South China University of Technology School of Electronic and Information Engineering South China University of Technology

Measuring the complex permittivity of ultrathin, flexible materials with a high loss tangent poses a substantial challenge with precision using conventional methods, and verifying the accuracy of test results remains difficult. In this study, we introduce a methodology based on a back-propagation artificial neural network(ANN) to extract the complex permittivity of paper-based composites(PBCs). PBCs are ultrathin and flexible materials exhibiting considerable complex permittivity and dielectric loss tangent. Given the absence of mature measurement methods for PBCs and a lack of sufficient data for ANN training, a mapping relationship is initially established between the complex permittivity of honeycomb-structured microwave-absorbing materials(HMAMs, composed of PBCs) and that of PBCs using simulated data. Leveraging the ANN model, the complex permittivity of PBCs can be extracted from that of HMAMs obtained using standard measurement. Subsequently, two published methods are cited to illustrate the accuracy and advancement of the results obtained using the proposed approach. Additionally, specific error analysis is conducted, attributing discrepancies to the conductivity of PBCs, the homogenization of HMAMs, and differences between the simulation model and actual objects. Finally, the proposed method is applied to optimize the cell length parameters of HMAMs for enhanced absorption performance. The conclusion discusses further improvements and areas for extended research.

关键词： paper-based composite honeycomb complex permittivity artificial neural networks inverse modeling

Study on Catalytic Behavior of Iron-based Catalyst with IITP as Electron Donor in the Polymerization of Butadiene

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Chinese Journal of Polymer Science 2024年第5期42卷 612-619,I0007页

作者： Shi-Liang Xu Ying-Nan Zhao yao Yu Qi Yang Li-Hua Na Heng Liu Chun-Yu Zhang Xue-quan Zhang Key Laboratory of Advanced Rubber Material Ministry of EducationSchool of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China Shandong Provincial College Laboratory of Rubber Material and Engineering School of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China Key Lab of Rubber-Plastics Ministry of Education/Shandong Provincial Key Lab of Rubber-plasticsSchool of Polymer Science and EngineeringQingdao University of Science&TechnologyQingdao266042China

In this study,a novel iron-based catalyst system,Fe(acac)3/(isocyanoimino)triptenylphosphorane(IITP)/AlR3,was employed for the synthesis of syndiotactic 1,2-polybutadiene in *** catalyst system exhibits remarkably high catalytic activity,achieving a polymerization activity of 762 kgpolymer·molcatalyst^(-1)·h^(-1)at 50℃with a[BD]/[Fe]molar ratio of ***,living polymerization characteristic were observed during the investigation of the polymerization kinetics of 1,3-butadiene *** characteristics were well demonstrated by a narrow molecular weight distribution(PDI≈2.0)of the resulting polybutadiene and a linear relationship between-ln(1-c)and polymerization time as well as number average molecular weight and polymer *** resultant polymer showed a 1,2-selectivity of approximately 76%and stereoregularity ranging from 62%to 73%(rrrr).Additionally,through kinetic studies on polymerization reaction,an apparent activation energy Ea value of this catalytic system was calculated to be 84.98 kJ·mol^(-1),which suggests that high polymerization temperature favors efficient polymerization.

关键词： Iron catalyst Syndiotactic 1,2-polybutadiene Elastomers Donor Selectivity

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THz辐射的研究和应用新进展

光电子．激光 2005年第4期16卷 503-510页

作者：姚建铨路洋张百钢王鹏天津大学精仪学院激光与光电子研究所

THz频段是一个非常具有科学价值但尚未开发的电磁辐射区域,它的研究涉及物理学、光电子学及材料科学等,它在成像、医学诊断、环境科学、信息通信及基础物理研究领域有着广阔的应用前景和应用价值。当今,获得THz波的方法及THz波的探测研... 详细信息

THz频段是一个非常具有科学价值但尚未开发的电磁辐射区域,它的研究涉及物理学、光电子学及材料科学等,它在成像、医学诊断、环境科学、信息通信及基础物理研究领域有着广阔的应用前景和应用价值。当今,获得THz波的方法及THz波的探测研究是THz研究领域的前沿,更是重点。本文综述了THz波的特点、应用领域及发展状况,阐述了THz波的产生方法其探测方法。

关键词：研究和应用 THz辐射研究领域科学价值材料科学光电子学医学诊断环境科学应用价值基础物理信息通信发展状况应用领域探测方法产生方法辐射区物理学频段

Assessment of the three representative empirical models for zenith tropospheric delay(ZTD)using the CMONOC data

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Geodesy and Geodynamics 2024年第5期15卷 488-494页

作者： Debao Yuan jian Li Yifan yao Fei Yang Yingying Wang Ran Chen Tairan Xu College of Geoscience and Surveying Engineering China University of Mining and Technology-BeijingBeijing100083China Hubei Luojia Laboratory Wuhan430079China

The precise correction of atmospheric zenith tropospheric delay(ZTD)is significant for the Global Navigation Satellite System(GNSS)performance regarding positioning accuracy and convergence *** the past decades,many empirical ZTD models based on whether the gridded or scattered ZTD products have been proposed and widely used in the GNSS positioning *** there is no comprehensive evaluation of these models for the whole China region,which features complicated topography and *** this study,we completely assess the typical empirical models,the IGGtropSH model(gridded,non-meteorology),the SHAtropE model(scattered,non-meteorology),and the GPT3 model(gridded,meteorology)using the Crustal Movement Observation Network of China(CMONOC)*** general,the results show that the three models share consistent performance with RMSE/bias of 37.45/1.63,37.13/2.20,and 38.27/1.34 mm for the GPT3,SHAtropE and IGGtropSH model,***,the models had a distinct performance regarding geographical distribution,elevation,seasonal variations,and daily *** the southeastern region of China,RMSE values are around 50 mm,which are much higher than that in the western region,approximately 20 *** SHAtropE model exhibits better performance for areas with large variations in *** GPT3 model and the IGGtropSH model are more stable across different months,and the SHAtropE model based on the GNSS data exhibits superior performance across various UTC epochs.

关键词： GNSS Zenith tropospheric delay Empirical ZTD model CMONOC data