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Science China(Information Sciences) 2024年第2期67卷 337-338页

作者： Yutong HE Xinhai ZOU Ying XU Zhihui LI Naidi CUI Junbo FENG Yali ZHANG Zhiyao ZHANG Shangjian ZHANG Yong LIU ninghua zhu Research Center for Microwave Photonics State Key Laboratory of Electronic Thin Films and Integrated DevicesSchool of Optoelectronic Science and EngineeringUniversity of Electronic Science and Technology of China Chongqing United Microelectronics Center (CUMEC) Xiongan Institute of Innovation Chinese Academy of Sciences

Photonic integrated circuits(PICs) promise future parallelism growths of high-performance communication, computation, and offer unprecedented bandwidth scalability with reduced power consumption as a viable replacement for an electrical wire with an optoelectronic transceiver consisting of a transmitter and a receiver integrated on the same wafer.

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铁心杉种群结构与动态特征

中南林业科技大学学报 2024年第2期44卷 138-145页

作者：巩亚梅谢功良刘森朱宁华中南林业科技大学林学院湖南长沙410004

【目的】杉木是南方生长最快的主要树种之一,而铁心杉是心材比例高、具有防腐的特殊性质的杉木新品种,但其野生种群分布范围窄。研究铁心杉种群结构与动态特征,可以为铁心杉种群的恢复以及种质资源的培育提供理论基础。【方法】以湖南... 详细信息

【目的】杉木是南方生长最快的主要树种之一,而铁心杉是心材比例高、具有防腐的特殊性质的杉木新品种,但其野生种群分布范围窄。研究铁心杉种群结构与动态特征,可以为铁心杉种群的恢复以及种质资源的培育提供理论基础。【方法】以湖南小溪国家级自然保护区小溪乡的铁心杉天然林为研究对象,通过实地调查以胸径代替龄级,制作年龄结构图;以静态生命表制作存活、死亡和消失率曲线;以生存函数估计值制作生存函数曲线;计算了种群动态变化指数;预测了种群数量的时间序列。【结果】1)铁心杉种群的龄级结构属于不规则金字塔形,种群有一定的更新能力,第Ⅰ龄级储备丰富,但幼龄阶段死亡率高,铁心杉种群存活曲线趋Deevey-Ⅲ型;2)铁心杉种群在整个龄级中的死亡率和消失率曲线走向一致,在第XIII龄级出现最大值,而第Ⅰ龄级次之,因此铁心杉种群的更新和结构受到了空间资源的限制;3)经过生存分析,发现铁心杉的生存能力相对较差,在早期阶段会出现剧烈的下降,中期保持稳定,后期则会出现衰退;4)时间序列分析显示,整个铁心杉种群向中、高龄级集中,低龄的缺失会导致种群衰退。【结论】应尽快确定铁心杉的生态学地位,并采取就地保护以确保种群的更新;同时建议通过组织培养、引种栽培来保护铁心杉种质资源,扩大其分布范围。

关键词：铁心杉种群静态生命表生存分析动态指数

Recent advances in microwave photonics

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Frontiers of Optoelectronics 2016年第2期9卷 160-185页

作者： Ming LI ninghua zhu State Key Laboratory on Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China

Microwave photonics （MWP） is an interdisci- plinary field that combines two different areas of microwave engineering and photonics. It has several key features by transferring signals between the optical domain and microwave domain, which leads to the advantages of broad operation bandwidth for generation, processing and distribution of microwave signals and high resolution for optical spectrum measurement. In this paper, we comprehensively review past and current status of MWP in China by introducing the representative works from most of the active MWP research groups. Future prospective is also discussed fi＇om the national strategy to key enabling technology that we have developed.

关键词： microwave photonics (MWP) integratedmicrowave photonics (IMWP) optical analog device andsystem direct modulation laser radio over fiber phasestabilized analog optical link optoelectronic oscillators(OEOs) microwave photonics filter (MPF) arbitrarywaveform generation (AWG) optical phase locked looping(OPLL) microwave photonics front-ends (MWP-FE),optical vector network analyzer

配方施肥对铁心杉幼苗生长和生理生化指标的影响

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福建农林大学学报（自然科学版） 2024年第1期53卷 48-55页

作者：杨捷朱宁华杨海洋谢功良中南林业科技大学林学院湖南长沙410004

【目的】旨在寻找最适合铁心杉幼苗生长的肥料配比。【方法】采用“3414”试验设计方案,设置14组肥料配比,以每组50盆的1年生铁心杉实生苗为材料,探究不同肥料配比对幼苗生长和生理生化指标的影响。【结果】与不施肥相比,合理施肥的铁... 详细信息

【目的】旨在寻找最适合铁心杉幼苗生长的肥料配比。【方法】采用“3414”试验设计方案,设置14组肥料配比,以每组50盆的1年生铁心杉实生苗为材料,探究不同肥料配比对幼苗生长和生理生化指标的影响。【结果】与不施肥相比,合理施肥的铁心杉幼苗叶片的叶绿素含量最高提高了42.01%,可溶性糖含量最高提高了11.64%,可溶性蛋白含量最高提高了13.81%,游离脯氨酸含量最高提高了211.25%;在N_(2)P_(2)K_(1)的肥料配方下,铁心杉幼苗的苗高、根直径、地上生物量、地下生物量、总生物量及苗木质量指数达到最大值,地径、根表面积和总根长也处于中上水平。【结论】N_(2)P_(2)K_(1)(每盆施1.0 g N、1.0 g P、0.5 g K)是铁心杉幼苗最佳的施肥配方。

关键词：铁心杉苗木培育肥料配比生长指标生理生化指标苗木质量

Calibration of microwave network analyzer

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Science China(Technological Sciences) 2004年第2期47卷 141-149页

作者： zhu ninghua WANG Youlin CHEN Zhenyu The State Key Laboratory on Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China The State Key Laboratory on Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China The State Key Laboratory on Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences Beijing 100083 China

This paper presents a systematic description of the methods for calibrating microwave network analyzer and test fixtures, and discusses the problems arising in the calibration. The general criteria for choosing calibration standards and corresponding algorithms are discussed and suggestions to overcome these problems and improve the calibration accuracy are also given. It has been found that for reciprocal test fixtures, the four equations obtained with the thru standard can be used at the same time. Meanwhile,the calibration accuracy can be improved. It has been shown that using the same calibration procedures but different algorithms may lead to the occurrence of frequency limitation.

关键词： calibration, microwave network analyzer, scattering parameter measurement, test fixture.

Dissipative microwave photonic solitons in spontaneous frequency-hopping optoelectronic oscillators

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Photonics Research 2022年第5期10卷 1280-1289页

作者： TENGFEI HAO HAO DING WEI LI ninghua zhu YITANG DAI MING LI State Key Laboratory on Integrated Optoelectronics Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of SciencesBeijing 100049China Center of Materials Science and Optoelectronics Engineering University of Chinese Academy of SciencesBeijing 100190China State Key Laboratory of Information Photonics and Optical Communications Beijing University of Posts and TelecommunicationsBeijing 100876China Peng Cheng Laboratory Shenzhen 518052China

Dissipative solitons relying on the double balance between nonlinear and linear effects as well as cavity loss and gain have attracted increasing attention in recent years,since they give rise to novel operating states of various dissipative nonlinear *** optoelectronic oscillator(OEO)is a dissipative nonlinear microwave photonic system with a high quality factor that has been widely investigated for generating ultra-low noise single-frequency microwave ***,we report a novel operating state of an OEO related to dissipative solitons,i.e.,spontaneous frequency hopping related to the formation of dissipative microwave photonic *** this operating state,dissipative microwave photonic solitons occur due to the double balance between nonlinear gain saturation and linear filtering as well as cavity loss and gain in the OEO cavity,creating spontaneous frequencyhopping microwave *** generation of wideband tunable frequency-hopping microwave signals with a fast frequency-hopping speed up to tens of nanoseconds is observed in the experiment,together with the corresponding soliton *** work reveals a novel mechanism between the interaction of nonlinear and linear effects in an OEO cavity,extends the suitability and potential applications of solitons,and paves the way for a new class of soliton microwave photonic systems for the generation,processing,and control of microwave and RF signals.

关键词： microwave solitons dissipative

35 km amplifier-less four-level pulse amplitude modulation signals enabled by a 23 GHz ultrabroadband directly modulated laser

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Journal of Semiconductors 2020年第3期41卷 45-48页

作者： Yaoping Xiao Yu Liu Yiming Zhang Haotian Bao ninghua zhu State Key Laboratory on Integrated Optoelectronics Institution of SemiconductorsChinese Academy of SciencesBeijing 100083China School of Electronic Electrical and Communication EngineeringUniversity of Chinese Academy of SciencesBeijing 100049China

The 4-level pulse amplitude modulation(PAM4)based on an 23 GHz ultrabroadband directly modulated laser(DML)was *** have experimentally demonstrated that based on intensity modulation and direct detection(IMDD)56 Gbps per wavelength PAM4 signals transferred over 35 km standard single mode fiber(SSMF)without any optical amplification and we have achieved the bit error rate(BER)of the PAM4 transmission was under 2.9×10–4 by using feed forward equalization(FFE).

关键词： directly modulated laser PAM4 FFE IMDD

Optical length-change measurement based on an incoherent single-bandpass microwave photonic filter with high resolution

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Photonics Research 2014年第4期2卷 35-39页

作者： Ye Deng Ming Li Ningbo Huang Hui Wang ninghua zhu State Key Laboratory on Integrated Optoelectronics Institute of SemiconductorsChinese Academy of SciencesBeijing 100083China

An optical length-change measurement technique is proposed based on an incoherent microwave photonic filter(MPF).The optical length under testing is inserted into an optical link of a single-bandpass MPF based on a polarization-processed incoherent light *** key feature of the proposed technique is to transfer the length measurement in the optical domain to the electrical *** the electrical domain,the measurement resolution is extremely high thanks to the high-resolution measurement of microwave frequency *** addition,since the MPF is a single-bandpass MPF,the optical length is uniquely determined by the central frequency of the MPF.A detailed investigation of the relation between the center frequency of the MPF and the optical length change is implemented.A measurement experiment is also demonstrated,and the experimental results show that the proposed technique has a measurement sensitivity of 1 GHz/mm with a high length-measurement resolution of 1 pm in *** proposed approach has the advantages of high sensitivity,high resolution,and immunity to power variation in electronic and optical links.

关键词： filter polarization microwave

Optically controlled phase array antenna [Invited]

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Chinese Optics Letters 2019年第5期17卷 72-77页

作者： Nuannuan Shi Wei Li ninghua zhu Ming Li State Key Laboratory on Integrated Optoelectronics Institute of SemiconductorsChinese Academy of Sciences Beijing 100083China University of Chinese Academy of Sciences Beijing 100049China

To overcome the beam squint in wide instantaneous frequency, we review a number of system-level optical controlled phase array antennas for beam forming. The optical delay network based on a fiber device in terms of topological structure of an N-bit optical switch, fiber grating, high-dispersion fiber, and vector-sum technology is discussed, respectively. Lastly, an integrated circuit is simply summarized.

关键词： Optically controlled phase array antenna wide instantaneous frequency

Selectable infiltrating large hollow core photonic band-gap fiber

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Chinese Science Bulletin 2013年第21期58卷 2606-2610页

作者： LIU JianGuo DU YuanXin zhu ninghua LIU FengMei State Key Laboratory of Integrated Optoelectronics Institute of Semiconductors Chinese Academy of Sciences Haidian Maternal & Child Health Hospital

A selectable infiltrating large hollow core photonic band-gap fiber is fabricated with simple arc discharge technique. The offset, discharge duration, arc current and discharge times are optimized for selected sealing side air-holes but leave the central large air-hole partially open. The collapse length of the PCF is shortened by increasing the number of discharges and offset with discharge duration and arc current kept at a relatively low level. Light with the wavelength located at the photonic band-gap can still propagate while the central hollow air-hole is infiltrated with a kind of oil with refractive index of 1.30. The selectable infiltrating large hollow core photonic band-gap fiber has potential application for implementing novel lasers, sensors and tunable optoelectronic devices.

关键词：光子带隙光纤空芯渗透放电技术电弧电流光子晶体光纤放电时间光子学器件