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苯甲酰基异氰酸酯中关键杂质对氟铃脲质量的影响

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农药 2024年第5期63卷 337-340页

作者：田俊杰刘宝宏张斌铨李凇宇张涛孙在臣德州绿霸精细化工有限公司山东德州253000 山东恒东生物科技有限公司山东平原253100

[目的]对2,6-二氟苯甲酰基异氰酸酯中主要杂质进行定性分析,浅谈杂质的生成机理,优化车间生产工艺以达到减少或去除该杂质的目的。[方法]对2,6-二氟苯甲酰基异氰酸酯中的组分进行GC-MS和LC-MS分析。[结果]影响氟铃脲质量的2,6-二氟苯甲... 详细信息

[目的]对2,6-二氟苯甲酰基异氰酸酯中主要杂质进行定性分析,浅谈杂质的生成机理,优化车间生产工艺以达到减少或去除该杂质的目的。[方法]对2,6-二氟苯甲酰基异氰酸酯中的组分进行GC-MS和LC-MS分析。[结果]影响氟铃脲质量的2,6-二氟苯甲酰基异氰酸酯中关键杂质是N^(1),N^(2)-双(2,6-二氟苯甲酰基)草酰胺(杂质A)。[结论]优化合成工艺能有效减少2,6-二氟苯甲酰基异氰酸酯中的杂质A,改进工艺后杂质A降低了97.8%,能够明显提升2,6-二氟苯甲酰基异氰酸酯的含量。

关键词：氟铃脲苯甲酰基异氰酸酯杂质 GC-MS LC-MS

Radio Frequency Fingerprint-Based Satellite TT&C Ground Station Identification Method

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Journal of Beijing Institute of Technology 2023年第1期32卷 1-12页

作者： Xiaogang Tang Junhao Feng binquan zhang Hao Huan School of Aerospace Information Space Engineering UniversityBeijing 101407China School of Information and Electronics Beijing Institute of TechnologyBeijing 100081China

This study presents a radio frequency(RF)fingerprint identification method combining a convolutional neural network(CNN)and gated recurrent unit(GRU)network to identify measurement and control *** proposed algorithm(CNN-GRU)uses a convolutional layer to extract the IQ-related learning timing features.A GRU network extracts timing features at a deeper level before outputting the final identification *** number of parameters and the algorithm’s complexity are reduced by optimizing the convolutional layer structure and replacing multiple fully-connected layers with gated cyclic *** experiments show that the algorithm achieves an average identification accuracy of 84.74% at a -10 dB to 20 dB signal-to-noise ratio(SNR)with fewer parameters and less computation than a network model with the same identification rate in a software radio dataset containing multiple USRP X310s from the same manufacturer,with fewer parameters and less computation than a network model with the same identification *** algorithm is used to identify measurement and control signals and ensure the security of the measurement and control link with theoretical and engineering applications.

关键词： measurement and control security radio frequency(RF)fingerprinting identity identification deep learning

The geometric factor of high energy protons detector on FY-3 satellite

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Science China Earth Sciences 2014年第11期57卷 2558-2566页

作者： zhang ShenYi zhang XianGuo WANG ChuiQin SHEN GuoHong JIN Tao zhang binquan SUN YueQiang ZHU GuangWu LIANG JinBao zhang XiaoXin LI JiaWei HUANG Cong HAN Ying Center for Space Science and Applied Research Chinese Academy of Sciences National Center for Space Weather Beijing Institute of Petrochemical Technology

Geometric factor is the key parameter for inversion of particle spectrum in space particle detection. Traditional geometric factor is obtained through the method of numerical calculation with the actual structure of the detector as the input condition. The degree of accuracy for data inversion is reduced since traditional geometric factor fails to take into account the physical process of interaction between the particle and substance as well as the influence of factors such as the particle interference between different energy channels on the measurement result. Here we propose an improved geometrical factor calculation method, the concept of which is to conduct actual structural modelling of the detector in the GEANT4 program, consider the process of interaction between the particle and substance, obtain the response function of the detector to particles of different energy channels through the method of Monte Carlo simulation, calculate the influence of contaminated particle on the geometrical factor, and finally get the geometrical factors for different energy channels of the detector. The imrpoved geometrical factor obtained through the method has carried out inversion for the data of high energy protons detector on China's FY-3 satellite, the energy spectrum after which is more in line with the power law distribution recognized by space physics. The comparison with the measured result of POES satellite indicates that the FY-3 satellite data are in good accordance with the satellite data, which shows the method may effectively improve the quality of data inversion.

关键词：卫星数据高能质子探测器几何要素蒙特卡罗模拟方法几何因子数值计算 GEANT4

Proton belt variations traced back to Fengyun-1C satellite observations

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Earth and Planetary Physics 2020年第6期4卷 611-618页

作者： ChunQin Wang Zheng Chang XiaoXin zhang GuoHong Shen ShenYi zhang YueQiang Sun JiaWei Li Tao Jing HuanXin zhang Ying Sun binquan zhang National Space Science Center Chinese Academy of SciencesBeijing 100190China Beijing Key Laboratory of Space Environment Exploration Beijing 100190China Environmental Space Situation Awareness-SSA Beijing 100190China National Center for Space Weather China Meteorological AdministrationBeijing 100081China

We used historical data to trace trapped protons observed by the Fengyun-1C(FY-1C)satellite at low Earth orbits(~800 km)and chose data at 5–10 MeV,10–40 MeV,40–100 MeV,and^100–300 MeV from 25 March to 18 April 2000 to analyze the proton *** one isolated strong storm was associated with a solar proton event during this period,and there was no influence from previous proton *** dynamic phenomena of proton trapping and loss were affected by this disturbance differently depending on the energy and L *** flux of 5–10 MeV protons increased and created new trapping with a maximum at L^2.0,and the peak flux was significantly higher than that at the center of the South Atlantic ***,at higher L,the flux showed obvious loss,with retreat of the outer boundary from L^2.7 to L^*** increase in the 10–40 MeV proton flux was similar to that of the 5–10 MeV flux;however,the peak flux intensity was lower than that at the center of the South Atlantic *** loss of the 10–40 MeV proton flux was closer to the Earth side,and the outer boundary was reduced from L^2.3 to L^*** the higher energy protons of 40–100 MeV and 100–300 MeV,no new trapping was *** of the 40–100 MeV protons was observed,and the outer boundary shifted from L^2.0 to L^*** was not obvious for the 100–400 MeV protons,which were distributed within L<*** proton trapping was more likely to be created at lower energy in the region of solar proton injection by the strong magnetic storm,whereas loss occurred in a wide energy range and reduced the outer boundary on the Earth *** dynamic changes were observed by the NOAA-15 satellite in the same period,but the FY-1C satellite observed more complex changes in lower energy *** results revealed that the dynamic behavior of protons with different L-shells was due to differences in the pitch *** mechanisms related to new trapping and loss are also *** mechanisms ar

关键词： high-energy proton trapping loss disturbance inner radiation belt

Super solar particle event around AD775 was found

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Chinese Science Bulletin 2014年第22期59卷 2736-2742页

作者： Dazhuang Zhou Chi Wang binquan zhang Shenyi zhang Ping Zhou Yueqiang Sun Jinbao Liang Guangwu Zhu Ji Wu National Space Science Center Chinese Academy of Sciences

A rapid radiocarbon14C increase of 120/00in AD774–775 has been reported in cedar and oak tree *** far,the origin of the14C increase is still uncertain and the possible origin is either supernova or solar particle *** most possible origin of14C increase is strong solar flares and Coronal Mass Ejections(CMEs)with strong particles *** approaches to identify the strong historical solar particle events based on the rapid14C/10Be increase in tree/coral rings and ice cores,long duration strong auroras and geomagnetic storms are *** of the super auroras in AD775 was first found in a Chinese Chronicles Jiutangshu and it supports the views that the rapid14C increase and strong auroras around AD775 are most possibly caused by strong solar storms with intense particles *** was identified that the solar event around AD775 would be the strongest solar particle event in the past 11400 *** discovery is significant for the research on the history of solar activities,space weather and forecast,radiation of solar energetic particles and protection.

关键词：太阳耀斑子事件日冕物质抛射太阳高能粒子粒子辐射太阳风暴 14C 放射性碳

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基于射频指纹的卫星测控地面站身份识别方法

电子与信息学报 2023年第7期45卷 2554-2560页

作者：唐晓刚冯俊豪张斌权郇浩任彦洁李海滨航天工程大学信息学院北京101407 北京理工大学信息与电子学院北京100081

传统卫星测控通常采用加密认证安全机制,存在身份假冒、欺骗等安全问题,该文提出一种基于射频指纹的卫星测控地面站身份识别方法,并设计了一种面向星载平台的轻量化卷积神经网络。该网络首先使用IQ方向上的卷积层提取IQ信号相关特征,将... 详细信息

传统卫星测控通常采用加密认证安全机制,存在身份假冒、欺骗等安全问题,该文提出一种基于射频指纹的卫星测控地面站身份识别方法,并设计了一种面向星载平台的轻量化卷积神经网络。该网络首先使用IQ方向上的卷积层提取IQ信号相关特征,将2维数据降成了1维,再使用时序方向上的多层卷积提取信号的时域结构特征,之后使用最大池化层降低数据维度,在充分利用IQ信号中包含的原始特征信息的同时减小计算量,最后经过两层全连接层进行分类,实现对卫星测控地面站身份识别。仿真实验表明,该方法对21台发射机个体的平均准确率为93.8%,较传统的支持向量机方法提高了39.8%,较DLRF网络模型、ORACLE网络模型分别提高了11.5%,29.8%,且具有鲁棒性强、轻量化的优点。该文所提方法对于提高卫星测控链路安全性具有一定的理论参考和工程应用价值。

关键词：测控安全射频指纹身份识别深度学习

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基于时间卷积网络的通信信号调制识别算法

无线电工程 2023年第4期53卷 807-814页

作者：任彦洁唐晓刚张斌权冯俊豪航天工程大学航天信息学院北京101407

针对基于深度学习的端到端调制识别方法存在识别率较低、神经网络参数量大的问题,提出了一种基于时间卷积网络(Temporal Convolutional Network, TCN)的调制识别算法。利用一维因果膨胀卷积,提取信号的时域和频域特征,并加入批归一化(Ba... 详细信息

针对基于深度学习的端到端调制识别方法存在识别率较低、神经网络参数量大的问题,提出了一种基于时间卷积网络(Temporal Convolutional Network, TCN)的调制识别算法。利用一维因果膨胀卷积,提取信号的时域和频域特征,并加入批归一化(Batch Normalization, BN)和Dropout提高算法的拟合能力;使用全局平均池化(Global Average Pooling, GAP)层替代Flatten层,整合向量特征信息,进一步实现信号的准确分类。在RML 2016.10a数据集上验证了TCN算法的识别性能,在不同信噪比(Signal to Noise Ratio, SNR)下对11种调制信号的平均识别率达到62.3%,与CNN,LSTM和SCRNN算法相比分别提高了10.5%、4.1%、1.1%,参数量分别降低了98.8%、82.5%、91.2%。所提方法对于通信调制信号识别的研究领域具有理论参考价值,对复杂环境下的空间信号智能分类的研究具有工程借鉴意义。

关键词：调制识别时间卷积网络膨胀因果卷积全局平均池化

An experimental investigation on sound transmission loss and vibration reduction of a vessel in water

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Chinese Journal of Acoustics 1992年第1期11卷 49-54页

作者： SHAO Daoyuan,QIAN Zuwen, zhang binquan and SHANG Wancheng(Institute of Acoustics, Academia Sinica, Beijing 100080)

Experimental results of sound transmission loss in a range of frequency through bubbly curtains were obtained, where the air content was in a wide range by means of varying pressure differences and the diameters of th... 详细信息

关键词： An experimental investigation on sound transmission loss and vibration reduction of a vessel in water

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电子照射对硅漂移探测器性能的影响

北京航空航天大学学报 2013年第2期39卷 235-238页

作者：张斌全韦飞冷双王世金中国科学院空间科学与应用研究中心北京100190

由于高能电子辐射的长期照射,新一代太阳X射线探测器硅漂移传感器的探测性能可能发生变化.通过用电子放射源模拟空间电子对硅漂移探测器进行辐射照射试验,以测试电子照射对传感器能量分辨率、效率、信号幅度等性能的影响.试验结果表明,... 详细信息

由于高能电子辐射的长期照射,新一代太阳X射线探测器硅漂移传感器的探测性能可能发生变化.通过用电子放射源模拟空间电子对硅漂移探测器进行辐射照射试验,以测试电子照射对传感器能量分辨率、效率、信号幅度等性能的影响.试验结果表明,长期的电子照射造成硅漂移探测器面损伤和体损伤,使其漏电流增大,信号幅度减小,能量分辨率也受到照射的影响,而探测效率未发生变化.

关键词：太阳X射线硅漂移探测器电子照射