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基于光纤传输的太赫兹无线通信

微波学报 2018年第A1期34卷 278-281页

作者：袁雪琪张盟王学田高洪民常国兵北京理工大学信息与电子学院北京100081

针对500GHz以上的大气窗口频段,提出了一种基于光纤传输的THz通信系统。该通信系统的微波源由两个工作频率不同的激光器通过光混频器获得。接收机采取肖特基整流二极管进行直接接收。此外,分析了该THz通信系统中的关键器件设计及THz通... 详细信息

针对500GHz以上的大气窗口频段,提出了一种基于光纤传输的THz通信系统。该通信系统的微波源由两个工作频率不同的激光器通过光混频器获得。接收机采取肖特基整流二极管进行直接接收。此外,分析了该THz通信系统中的关键器件设计及THz通信中的关键问题。在硬件设计的基础上,讨论了信号调制方式对系统通信容量、传输距离和误码率的影响。

关键词： THz通信光混频器 THz信号调制

气相色谱测定人参和红参中16种有机氯农药残留量的方法研究

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粮食与油脂 2022年第11期35卷 152-157,162页

作者：宋莹莹郭畅冰王国明李健豪谢丽娟徐芳菲吉林人参研究院吉林通化134001

建立气相色谱测定人参和红参中16种有机氯农药残留量的方法,并对其进行验证。结果表明:16种有机氯农药在质量浓度0.001~0.100μg/mL范围内均呈现良好的线性关系,相关系数r≥0.999 68,且分离度良好;检出限(LOD)为0.001 3~0.003 7 mg/kg,... 详细信息

建立气相色谱测定人参和红参中16种有机氯农药残留量的方法,并对其进行验证。结果表明:16种有机氯农药在质量浓度0.001~0.100μg/mL范围内均呈现良好的线性关系,相关系数r≥0.999 68,且分离度良好;检出限(LOD)为0.001 3~0.003 7 mg/kg,定量限(LOQ)为0.004 0~0.011 0 mg/kg;人参、红参样品在0.010、0.050、0.100 mg/kg添加水平下的回收率为71.46%~118.34%;相对标准偏差(RSD)在1.14%~8.71%,符合农药残留相关分析标准<15%的要求。方法简便快速、灵敏度高,适用于人参和红参样品中16种有机氯农药残留量的测定。

关键词：气相色谱人参红参农药残留量

测定人参花中多种有机氯农药残留量的方法研究

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化学研究与应用 2023年第11期35卷 2568-2576页

作者：宋莹莹郭畅冰李健豪王国明谢丽娟娄子恒徐芳菲吉林人参研究院吉林长春130031

建立一种测定人参花中16种有机氯类农药残留量的方法,并对其进行方法学考察。方法样品经乙腈提取后,加入无水硫酸镁和氯化钠除水、分层,再通过N-丙基乙二胺(PSA)、十八烷基硅烷键合硅胶(C18)和无水硫酸镁净化,浓硫酸除水、脱色,采用气... 详细信息

建立一种测定人参花中16种有机氯类农药残留量的方法,并对其进行方法学考察。方法样品经乙腈提取后,加入无水硫酸镁和氯化钠除水、分层,再通过N-丙基乙二胺(PSA)、十八烷基硅烷键合硅胶(C18)和无水硫酸镁净化,浓硫酸除水、脱色,采用气相色谱法测定,外标法定量。16种有机氯农药在质量浓度0.001~0.100μg·mL^(-1)范围内均呈现良好的线性关系,相关系数r≥0.99914,且分离度良好;检出限(LOD)为0.00026~0.00073μg·mL^(-1),定量限(LOQ)为0.00080~0.0022μg·mL^(-1);人参花样品在0.0050、0.010、0.050、0.100 mg·kg^(-1)添加水平下的回收率为77.20%~116.87%;相对标准偏差(RSD)在1.31%~11.88%,符合农药残留相关分析标准<15%的要求。本实验所建立的方法简便快速、灵敏度高,适用于人参花中16种有机氯农药残留量的同时测定。

关键词：人参花有机氯农药残留气相色谱法

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人参皂苷结构修饰的研究进展

人参研究 2019年第6期31卷 57-60页

作者：谢丽娟苑冰冰李健豪徐芳菲李蕾王国明郭畅冰曹志强吉林人参研究院

人参为我国长白山道地药材,人参皂苷为其主要活性物质,其中以次级皂苷的药理活性最为突出。本文综述了人参皂苷结构修饰的物理转化法、化学转化法及生物转化法的研究进展,分别概述了三种方法的优缺点,并对人参皂苷结构修饰的研究前景进... 详细信息

人参为我国长白山道地药材,人参皂苷为其主要活性物质,其中以次级皂苷的药理活性最为突出。本文综述了人参皂苷结构修饰的物理转化法、化学转化法及生物转化法的研究进展,分别概述了三种方法的优缺点,并对人参皂苷结构修饰的研究前景进行了展望,为今后研究人参皂苷的结构修饰提供了参考,同时为人参化学成分的研究提供了理论依据。

关键词：人参皂苷结构修饰研究进展

遗传算法在电能质量监测装置优化设计中的应用研究

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电工电能新技术 2000年第3期19卷 65-68页

作者：常炳国吴浩扬刘君华郑雪梅西安交通大学西安710049

本文提出了基于遗传算法优化在线电能质量监测仪中的油气分离装置结构参数的一种新方法 ,并进行了分离油中气体实验研究 ,结果表明该方法行之有效。

关键词：电能质量监测装置优化设计遗传算法供电设备

Investigation on halogen-doped n-type SnTe thermoelectrics

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Rare Metals 2022年第11期41卷 3803-3814页

作者： chang-Rong guo bing-Chao Qin Dong-Yang Wang Li-Dong Zhao School of Materials Science and Engineering Beihang UniversityBeijing100191China

Recent theoretical predictions and experimental findings on the transport properties of n-type SnTe have triggered extensive researches on this simple binary compound,despite the realization of n-type SnTe being a great ***,Cl as a donor dopant can effectively regulate the position of Fermi level in Sn_(0.6)Pb_(0.4)Te matrix and successfully achieve the n-type transport behavior in *** outstanding power factor of~14.7μW·cm^(-1)·K^(-2) at 300 K was obtained for Cl-doped Sn_(0.6)Pb_(0.4)Te *** combining the experimental analysis with theoretical calculations,the transport properties of n-type SnTe thermoelectrics doped with different halogen dopants(Cl,Br,and I)were then systematically investigated and *** results demonstrated that Br and I had better doping efficiencies compared with Cl,which contributed to the well-optimized carrier concentrations of~1.03×10^(19)and~1.11×10^(19)cm^(-3)at 300 K,*** improved n-type carrier concentrations effectively lead to the significant enhancement on the thermoelectric performance of n-type *** study further promoted the experimental progress and deep interpretation of the transport features in n-type SnTe *** present results could also be crucial for the development of n-type counterparts for SnTe-based thermoelectric devices.

关键词： Thermoelectric performance n-type SnTe Halogen doping Doping efficiency

Evaluation of Component Activity in Molten MnO-SiO_(2)-Al_(2)O_(3)-CaO System with Model SELF-SReM4

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Journal of Iron and Steel Research International 2000年第1期7卷 6-8页

作者： ZHANG Xiao-bing JIANG guo-chang XU Kuang-di Shanghai University

A sub-regular solution model SELF-SReM4 used to evaluate activity of the components in a homogeneous region of a quaternary system has been developed in Shanghai Enhanced Laboratory of *** application of SELF-SReM4 in C-Mn-Fe-Si system without the SiC formation has been introduced in previous ***’s application for molten slag of MnO-SiO2-Al2O3-CaO was introduced in this *** provide a basis for the prediction of the metal-slag equilibrium conditions.

关键词： sub-regular solution model component activity m olten slag MnO-SiO2-Al2O3-CaO

Ipsilateral hemifacial microsomia with dextrocardia and pulmonary hypoplasia:A case report

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World Journal of Clinical Cases 2022年第9期10卷 2948-2953页

作者： Rui guo Shi-Hi chang bing-Qing Wang Qing-guo Zhang Department of Ear Reconstruction Plastic Surgery HospitalChinese Academy of Medical Sciences and Peking Union Medical CollegeBeijing 100000China

BACKGROUND Hemifacial microsomia(HFM)is a rare congenital malformation characterized by a combination of various anomalies,including the face,ears,eyes,and *** diagnosis for HFM is possible,and quite accurate ultrasound can detect obvious *** etiology is still unknown,although some hypotheses have been proposed,including gene mutation,chromosome anomaly,and environmental risk ***,there are few reports of pulmonary hypoplasia and dextrocardia in *** SUMMARY A 2-year-old boy presented to the ear reconstruction department of our hospital complaining of deviation of the face to the right side and auricular *** examination revealed facial asymmetry,preauricular skin tags,and concha-type microtia with stricture of the external auditory canal on the right *** magnetic resonance imaging showed bilateral semicircular canal dysplasia and bilateral internal auditory canals *** examination showed bilateral severe sensorineural hearing *** radiography and computed tomography showed dextrocardia and right pulmonary *** This case presented a rare finding and an unusual association of 3 malformations,ipsilateral HFM,pulmonary agenesis,and dextrocardia.

关键词： Hemifacial microsomia Oculoauriculovertebral spectrum Dextrocardia Pulmonary hypoplasia Congenital anomaly Case report

Prediction of maximum carbon element content in continuous casting billets of 82B cord steel based on statistics of extreme values method

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Journal of Iron and Steel Research International 2020年第10期27卷 1163-1169页

作者： Dong-wei guo Zi-bing Hou Jiang-hai Cao Zhong-ao guo Yi chang Guang-hua Wen College of Materials Science and Engineering Chongqing UniversityChongqing 400044China

The research of carbon content along the casting direction of 82B cord steel billets is of great significance for improvingthe quality of cord products from subsequent ***,the traditional segregation and billets quality evaluationmethods have certain limitations,such as sampling length and analysis *** affect the accuracy of quality *** statistics of extreme values(SEV)was introduced to predict the maximum value of carbon element contentalong the casting direction,which can quantitatively characterize the segregation *** size of the selected billet is150 mm×150 mm,and the sampling location is the centerline of the *** experiment was conducted by consideringthe effect of cooling intensity and casting speed on the maximum value of carbon element ***,the calculationresults show that the SEN method can predict the maximum value of carbon element content along the casting directionof 82B cord steel,and the SEV method is proved to be effective by analyzing the carbon distribution and fluctuation in *** some extent,the SEV method can break the limitations of the sampling length and analysis area by predicting themaximum value of carbon element on a larger range of continuous casting billets with few *** the continuouscasting process the increase in cooling intensity makes the surface shrinking rate increase,which can slow down the flowof solute-enriched liquid to the center,and the center segregation can be *** the other hand,the function area ofthe final electromagnetic stirring can be expanded with the increase in the casting speed,which can reduce the concentration of carbon element in the center of the billets and reduce the maximum value of carbon element *** can providea new theoretical reference for the quantitative calculation of carbon content in continuous casting billets and the qualityevaluation of continuous casting billcts.

关键词： Cord steel Continuous casting Casting direction Segregation Statistics of extreme values