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High-Power Raman Soliton Generation at 1.7 μm in All-Fiber Polarization-Maintaining Erbium-Doped Amplifier
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作者 徐子鹏 王萱 +2 位作者 姚传飞 杨林京 李平雪 《Chinese Physics Letters》 SCIE EI CAS CSCD 2024年第5期35-39,共5页
An all-fiber polarization maintaining high-power laser system operating at 1.7 μm based on the Ramaninduced soliton self-frequency shifting effect is demonstrated. The entirely fiberized system is built by erbiumdope... An all-fiber polarization maintaining high-power laser system operating at 1.7 μm based on the Ramaninduced soliton self-frequency shifting effect is demonstrated. The entirely fiberized system is built by erbiumdoped oscillator and two-stage amplifiers with polarization maintaining commercial silica fibers and devices, which can provide robust and stable soliton generation. High-power soliton laser with the average power of 0.28 W,the repetition rate of 42.7 MHz, and pulse duration of 515 fs is generated directly from the main amplifier.Our experiment provides a feasible method for high-power all-fiber polarization maintaining femtosecond laser generation working at 1.7 μm. 展开更多
关键词 polarization fiber amplifier
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Broadband Dual-Input Doherty Power Amplifier Design Based on a Simple Adaptive Power Dividing Ratio Function
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作者 Dai Zhijiang Zhong Kang +2 位作者 Li Mingyu Pang Jingzhou Jin Yi 《China Communications》 SCIE CSCD 2024年第5期97-112,共16页
In this paper,a simple adaptive power dividing function for the design of a dual-input Doherty power amplifier(DPA)is presented.In the presented approaches,the signal separation function(SSF)at different frequency poi... In this paper,a simple adaptive power dividing function for the design of a dual-input Doherty power amplifier(DPA)is presented.In the presented approaches,the signal separation function(SSF)at different frequency points can be characterized by a polynomial.And in the practical test,the coefficients of SSF can be determined by measuring a small number of data points of input power.Same as other dualinput DPAs,the proposed approach can also achieve high output power and back-off efficiency in a broadband operation band by adjusting the power distribution ratio flexibly.Finally,a 1.5-2.5 GHz highefficiency dual-input Doherty power amplifier is implemented according to this approach.The test results show that the peak power is 48.6-49.7d Bm,and the 6-d B back-off efficiency is 51.0-67.0%,and the saturation efficiency is 52.4-74.6%.The digital predistortion correction is carried out at the frequency points of 1.8/2.1GHz,and the adjacent channel power ratio is lower than-54.5d Bc.Simulation and experiment results can verify the effectiveness and correctness of the proposed method. 展开更多
关键词 BROADBAND doherty power amplifier dualinput efficiency enhancement load modulation
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Harmonic balance simulation of the influence of component uniformity and reliability on the performance of a Josephson traveling wave parametric amplifier
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作者 郑煜臻 熊康林 +1 位作者 冯加贵 杨辉 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第4期339-343,共5页
A Josephson traveling wave parametric amplifier(JTWPA),which is a quantum-limited amplifier with high gain and large bandwidth,is the core device of large-scale measurement and control systems for quantum computing.A ... A Josephson traveling wave parametric amplifier(JTWPA),which is a quantum-limited amplifier with high gain and large bandwidth,is the core device of large-scale measurement and control systems for quantum computing.A typical JTWPA consists of thousands of Josephson junctions connected in series to form a transmission line and hundreds of shunt LC resonators periodically loaded along the line for phase matching.Because the variation of these capacitors and inductors can be detrimental to their high-frequency characteristics,the fabrication of a JTWPA typically necessitates precise processing equipment.To guide the fabrication process and further improve the design for manufacturability,it is necessary to understand how each electronic component affects the amplifier.In this paper,we use the harmonic balance method to conduct a comprehensive study on the impact of nonuniformity and fabrication yield of the electronic components on the performance of a JTWPA.The results provide insightful and scientific guidance for device design and fabrication processes. 展开更多
关键词 Josephson traveling wave parametric amplifier(JTWPA) harmonic balance method YIELDS UNIFORMITY
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Three-channel CMOS transimpedance amplifier for LiDAR sensor receiver
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作者 LIU Ruqing ZHU Jingguo +3 位作者 JIANG Yan LI Feng JIANG Chenghao MENG Zhe 《Journal of Systems Engineering and Electronics》 SCIE EI CSCD 2024年第1期74-80,共7页
For time-of-flight(TOF)light detection and ranging(LiDAR),a three-channel high-performance transimpedance amplifier(TIA)with high immunity to input load capacitance is presented.A regulated cascade(RGC)as the input st... For time-of-flight(TOF)light detection and ranging(LiDAR),a three-channel high-performance transimpedance amplifier(TIA)with high immunity to input load capacitance is presented.A regulated cascade(RGC)as the input stage is at the core of the complementary metal oxide semiconductor(CMOS)circuit chip,giving it more immunity to input photodiode detectors.A simple smart output interface acting as a feedback structure,which is rarely found in other designs,reduces the chip size and power consumption simultaneously.The circuit is designed using a 0.5μm CMOS process technology to achieve low cost.The device delivers a 33.87 dB?transimpedance gain at 350 MHz.With a higher input load capacitance,it shows a-3 dB bandwidth of 461 MHz,indicating a better detector tolerance at the front end of the system.Under a 3.3 V supply voltage,the device consumes 5.2 mW,and the total chip area with three channels is 402.8×597.0μm2(including the test pads). 展开更多
关键词 transimpedance amplifier(TIA) three-channel regulated cascade(RGC) light detection and ranging(LiDAR)
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贵阳地区血小板捐献者HPA-1~6/10/15/21和HLA-A/B基因多态性研究
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作者 王军 侯仕芳 +4 位作者 王娇 雷雨 余娜杰 赵霞 朱思刚 《贵州医科大学学报》 CAS 2024年第5期686-690,共5页
目的研究贵阳地区机采血小板捐献者人类血小板抗原HPA-1~6/10/15/21及人类白细胞抗原HLA-A、B基因分布及多态性。方法采用实时荧光定量PCR法(qPCR)对287名贵阳地区机采血小板捐献者进行HPA-1~6/10/15/21和HLA-A、B基因分型,列举aa\ab\b... 目的研究贵阳地区机采血小板捐献者人类血小板抗原HPA-1~6/10/15/21及人类白细胞抗原HLA-A、B基因分布及多态性。方法采用实时荧光定量PCR法(qPCR)对287名贵阳地区机采血小板捐献者进行HPA-1~6/10/15/21和HLA-A、B基因分型,列举aa\ab\bb基因及HLA-A、B等位基因的分布情况、计算aa\ab\bb基因及HLA-A、B等位基因型频率。结果287名血小板捐献者HPA-1~6/10/15/21系统中,HPA-4和HPA-10的基因型均为aa型,不具有多态性;HPA-1,2,5,6和21主要以aa型为主;仅在HPA-3和HPA-15中检出bb型;杂合度最高的是HPA-15,HPA3杂合度居次;HLA-A位点检出14个等位基因,频率最高的3个是A*02(0.36)、A*11(0.33)和A*24(0.162;HLA-B位点检出23个等位基因,频率最高的4个是B*46(0.19)、B*15(0.149、B*40(0.14)和B*13(0.13)。结论贵阳地区机采血小板捐献者HPA-1~6/10/15/21和HLA-A、B基因存在多态性,需建立该地HPA/HLA基因分型血小板供者库服务于临床。 展开更多
关键词 血小板 人类血小板抗原 人类白细胞抗原 hpa/HLA基因 多态性 基因频率
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5G Wideband Bandpass Filtering Power Amplifiers Based on a Bandwidth-Extended Bandpass Matching Network 被引量:1
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作者 Weimin Wang Hongmin Zhao +1 位作者 Yongle Wu Xiaopan Chen 《China Communications》 SCIE CSCD 2023年第11期56-66,共11页
In this paper,a 5G wideband power amplifier(PA)with bandpass filtering response is synthesized using a bandwidth-extended bandpass filter as the matching network(MN).In this structure,the bandwidth(θ_(C))is defined a... In this paper,a 5G wideband power amplifier(PA)with bandpass filtering response is synthesized using a bandwidth-extended bandpass filter as the matching network(MN).In this structure,the bandwidth(θ_(C))is defined as a variable in the closedform equations provided by the microstrip bandpass filter.It can be extended over a wide range only by changing the characteristic impedances of the structure.Different from the other wideband MNs,the extension of bandwidth does not increase the complexity of the structure(order n is fixed).In addition,based on the bandwidth-extended structure,the wideband design of bandpass filtering PA is not limited to the fixed bandwidth of the specific filter structure.The theoretical analysis of the MN and the design flow of the PA are provided in this design.The fabricated bandpass filtering PA can support almost one-octave bandwidth(2-3.8 GHz),covering the two 5G bands(n41 and n78).The drain efficiency of 47%-60%and output power higher than 40 dBm are measured.Good frequency selectivity in S-parameter measurements can be observed. 展开更多
关键词 bandpass filtering bandwidth-extension fixed order power amplifier WIDEBAND
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Design and performance of a high-speed and low-noise preamplifier for SiPM 被引量:1
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作者 Xi‑Yang Wang Hong‑Yu Zhang +4 位作者 De‑Qing Fang Wan‑Bing He Xiao‑Long Wang Qi‑Bin Zheng Shi‑Ming Zou 《Nuclear Science and Techniques》 SCIE EI CAS CSCD 2023年第11期93-102,共10页
Considering the R&D for upgrading the K^(0)_(L) andμdetectors in the Belle II experiment using a scintillator and silicon pho-tomultiplier(SiPM),we designed a compact high-speed and low-noise preamplifier.The pre... Considering the R&D for upgrading the K^(0)_(L) andμdetectors in the Belle II experiment using a scintillator and silicon pho-tomultiplier(SiPM),we designed a compact high-speed and low-noise preamplifier.The preamplifier demonstrated a good gain stability,bandwidth of 426 MHz,baseline noise level ofσ≈0.6 mV,dynamic range of up to170 mV of the input signal amplitude,good time resolution of 20 ps,and it can be comprehensively applied to SiPMs.Adopting pole-zero-cancelation in the preamplifier reduces both the rise and fall times of the SiPM signal,which can significantly improve the time resolution and reduce the pile-up when using a large SiPM or an array of SiPMs.Various combinations of the preamplifier and several types of SiPMs demonstrated time resolutions better than 50 ps for most cases;when the number of detected photons was larger than 60,a time resolution of approximately 25 ps was achieved. 展开更多
关键词 Silicon photomultiplier High-speed amplifier Low noise High time resolution
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免疫性血小板输注无效患者HLA/HPA抗体特性分析及其对血小板输注效果的影响
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作者 范成艳 温玉洁 +6 位作者 张丹 廉雪 刘娜 孙铁成 王东梅 贾延军 李冬妹 《临床输血与检验》 CAS 2024年第3期353-358,共6页
目的 探讨免疫性血小板输注无效(PTR)患者HLA/HPA抗体特异性分布特征及其对血小板输注效果的影响。方法 本研究以86例免疫性PTR患者为研究对象,收集其性别、年龄、身高、体重、配血次数、疾病类型、输注前后血小板计数等临床资料,通过... 目的 探讨免疫性血小板输注无效(PTR)患者HLA/HPA抗体特异性分布特征及其对血小板输注效果的影响。方法 本研究以86例免疫性PTR患者为研究对象,收集其性别、年龄、身高、体重、配血次数、疾病类型、输注前后血小板计数等临床资料,通过微珠法进行HLA特异性抗体的检测,并分析抗体特性对血小板输注效果的影响。结果 86例PTR患者中,单独HLA抗体、单独HPA抗体、HLA+HPA抗体阳性的患者分别为72例(83.72%)、8例(9.30%)、6例(6.98%)。HLA抗体在各位点中检出频率最高的抗体对应等位基因分别为A*25:01、B*15:12、C*02:02(和C*17:01),检出率分别为81.48%、87.04%、48.15%;而对应抗原表位出现频率最高的前三位为163LG、97V、71ATD,检出率分别为87.04%、77.78%、74.07%。仅存在HLA抗体的患者,输注交叉配型相合血小板的24 h血小板计数纠正增加指数(CCI)及输注有效情况均明显优于随机血小板(P<0.01)。在血小板交叉配型阴性结果的患者中,HLA抗体强度与交叉配型相合血小板的24 h CCI值及输注有效情况呈负相关关系,强度越高,输注效果越差(P<0.01)。HLA抗体强度为中、低等水平的患者,输注交叉配型相合血小板的24 h CCI值及输注有效情况均优于输注随机血小板(P<0.05)。结论 本研究所得到的PTR患者HLA/HPA抗体特性及其对血小板输注效果影响的结果,可为血小板库建立时供者的选择提供指导,同时对临床PTR患者的治疗方式选择有一定的参考价值。 展开更多
关键词 免疫性血小板输注无效 HLA抗体 hpa抗体 抗体分布特征 24 h血小板计数纠正增加指数
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血小板HPA-3,HPA-15基因分型微滴式数字PCR检测体系的构建
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作者 孔小娇 王红梅 +1 位作者 段生宝 刘铁梅 《中国输血杂志》 2024年第1期1-8,共8页
目的建立血小板HPA-3,HPA-15基因分型的微滴式数字PCR(ddPCR)高灵敏检测方法,并初步探索应用于孕妇外周血胎儿游离DNA HPA抗原相容性检测的可行性。方法针对HPA-3,HPA-15的SNP突变位点,设计特异性引物及MGB探针,优化ddPCR退火温度及引... 目的建立血小板HPA-3,HPA-15基因分型的微滴式数字PCR(ddPCR)高灵敏检测方法,并初步探索应用于孕妇外周血胎儿游离DNA HPA抗原相容性检测的可行性。方法针对HPA-3,HPA-15的SNP突变位点,设计特异性引物及MGB探针,优化ddPCR退火温度及引物浓度等扩增条件,建立最佳反应体系,明确检验程序。对该检测方法进行方法学性能评估包括特异性、灵敏度、重复性和稳定性。利用ddPCR技术对2022年6月至2023年6月67例临床血液标本进行检测,将等位基因分型结果与基因测序结果比较,并对52例母体外周血胎儿游离DNA HPA抗原进行检测。结果检测血小板HPA-3,HPA-15的ddPCR方法,引物及探针特异性良好,HPA-3,HPA-15的最佳退火温度分别为:61.6℃,60.2℃;体系最佳引物浓度分别为:900 nM,700 nM;探针终浓度均为250 nM。拷贝数定量检测范围为:2~20000 copies,检测下限为0.1 copies/μL且线性良好。在低拷贝数标本中,HPA-3及HPA-15实际检测值的批内及批间变异系数(CV)均<5%。对67份人血液标本DNA的HPA-3,HPA-15基因型检测,结果与基因测序结果完全一致。应用于胎母血小板HPA-3,HPA-15基因型检测结果符合预期。结论本研究构建的HPA-3,HPA-15 ddPCR检测体系准确性高,重复性及稳定性较好,灵敏度高,可应用于临床血小板HPA-3,HPA-15基因型供者库的建立、基因配型及胎母血小板相容性检测等。 展开更多
关键词 hpa 微滴式数字PCR 基因分型 基因频率
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童年期创伤后亲子关系对青少年社会适应的影响:HPA轴系统多基因的调节
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作者 曾子豪 刘双金 +8 位作者 杨琴 王宏才 刘承珍 赵纤 孟莉 何震 刘秀茹 黄宁 胡义秋 《心理学报》 CSCD 北大核心 2024年第8期1091-1109,I0004-I0012,共28页
童年期的不良经历似乎增加了个体对压力刺激的敏感性,从而可能影响其终身的社会适应。许多研究表明,HPA轴系统基因可能在调节环境因素与社会适应之间发挥作用。然而,过去单个基因与环境相互作用对社会适应的影响存在争议。本研究针对青... 童年期的不良经历似乎增加了个体对压力刺激的敏感性,从而可能影响其终身的社会适应。许多研究表明,HPA轴系统基因可能在调节环境因素与社会适应之间发挥作用。然而,过去单个基因与环境相互作用对社会适应的影响存在争议。本研究针对青少年样本(14.15±0.63岁;N=700),采用多位点遗传谱评分(multilocus genetic profile scores,MGPS)计算HPA轴系统多基因得分,利用纵向数据探究其与童年期创伤和亲子关系之间的相互作用,并预测青少年的社会适应(包括抑郁症状、亲社会行为和自伤行为)。研究结果显示,青少年的社会适应(包括抑郁症状和亲社会行为)是遗传(HPA轴系统MGPS)、远端环境(童年期创伤)和近端环境(亲子关系)三者相互作用的结果。随着遗传风险评分的增加,童年期创伤和亲子关系之间的交互作用也增加,这意味着遭受过童年期创伤的个体,亲子关系对社会适应的影响会更加显著,符合差别易感性模型。行为学实验进一步揭示了遗传和环境因素对青少年社会适应的潜在机制。 展开更多
关键词 青少年社会适应 亲子关系 童年期创伤 多基因 hpa 轴系统
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南昌地区血小板供者HLA-A、B和HPA基因多态性分析及分型库的建立
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作者 徐晶 舒轶 +4 位作者 杜忻 余真强 徐晓琴 周斌 魏小文 《现代诊断与治疗》 CAS 2024年第2期159-161,171,共4页
目的通过对血小板捐献者HLA-A、B和HPA 1-6,10,15,21基因位点的检测,分析基因位点分布特点,加强南昌地区血小板供者资料库的建设,保障临床血小板输注的有效性、及时性,提高临床输血疗效。方法对南昌地区800位血小板捐献者血样,采用荧光... 目的通过对血小板捐献者HLA-A、B和HPA 1-6,10,15,21基因位点的检测,分析基因位点分布特点,加强南昌地区血小板供者资料库的建设,保障临床血小板输注的有效性、及时性,提高临床输血疗效。方法对南昌地区800位血小板捐献者血样,采用荧光定量PCR的方法,对HLA-A、B位点、HPA 1-6,10,15,21位点进行基因分型,计算基因频率和基因型频率。结果HLA-A、B位点共检出HLA-A、HLA-B等位基因45个,其中HLA-A等位基因16个,频率较高的有A2、A11、A24;检出HLA-B等位基因29个,频率较高的有B13、15、B40、B46。HPA 1-6,10,15,21位点不配合率较高的是HPA3和HPA15,除此之外不配合率均低于10%。结论南昌地区人群与其它汉族地区HPA-HLA基因多态性类似。考虑其它汉族地区基因资料库计算结果和南昌ABO血型分布频率,资料库总人数需要达到7000人才能比较好的满足患者需求。 展开更多
关键词 血小板 HLA分型 hpa分型 基因频率 基因型频率
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Impact of amplified spontaneous emission noise on the SRS threshold of high-power fiber amplifiers
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作者 刘伟 任帅 +1 位作者 马鹏飞 周朴 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第3期234-238,共5页
Impact of amplified spontaneous emission(ASE)noise on the stimulated Raman scattering(SRS)threshold of highpower fiber amplifiers is demonstrated numerically through a spectral evolution approach.The simulation result... Impact of amplified spontaneous emission(ASE)noise on the stimulated Raman scattering(SRS)threshold of highpower fiber amplifiers is demonstrated numerically through a spectral evolution approach.The simulation results confirm that ASE noise in the Raman wavelength band could reduce the SRS threshold of high-power fiber amplifiers significantly.As for ASE noise originated the main amplifier,it becomes stronger and reduces the SRS threshold at shorter operation wavelength below 1052 nm.As for ASE noise originated from the seed laser,it reduces the SRS threshold at different operation wavelength under the condition that the Raman ratio is over-90 dB in the seed laser.The theoretical method and results in this work could provide a well reference to extend the operation wavelength of high-power fiber lasers. 展开更多
关键词 high-power fiber amplifiers amplified spontaneous emission stimulated Raman scattering
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精神障碍类疾病HPA轴相关组织体积病理特征研究进展
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作者 杨采幸 刘艳芬 +3 位作者 商文婷 李淑静 曲嵩霖 郭英慧 《临床与实验病理学杂志》 CAS 北大核心 2024年第3期307-310,共4页
下丘脑-垂体-肾上腺(hypothalamic-pituitary-adrenal axis,HPA)轴是机体内平衡、应激反应、能量代谢和神经精神功能的中心,HPA轴功能和结构异常,常见于精神障碍类疾病。下丘脑、垂体、肾上腺是HPA轴的核心组成,海马、前额叶皮层负反馈... 下丘脑-垂体-肾上腺(hypothalamic-pituitary-adrenal axis,HPA)轴是机体内平衡、应激反应、能量代谢和神经精神功能的中心,HPA轴功能和结构异常,常见于精神障碍类疾病。下丘脑、垂体、肾上腺是HPA轴的核心组成,海马、前额叶皮层负反馈调节该轴,杏仁核对HPA轴有激活作用,以上区域在结构体积的病理改变影响HPA轴激素水平。该文对HPA轴相关组织结构在精神障碍类疾病的病理改变作一综述,以期为研究精神障碍类疾病的病理机制提供参考。 展开更多
关键词 精神障碍 hpa 体积 病理特征 文献综述
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Improving source-in-the-middle continuous-variable quantum key distribution using a heralded hybrid linear amplifier
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作者 伍磊鑫 冯艳艳 周健 《Chinese Physics B》 SCIE EI CAS CSCD 2023年第7期290-295,共6页
A hybrid linear amplifier is inserted at the output of the source-in-the-middle distribution protocol to overcome the shortcomings of the transmission distance.The modified protocol aims to maintain a high key rate fo... A hybrid linear amplifier is inserted at the output of the source-in-the-middle distribution protocol to overcome the shortcomings of the transmission distance.The modified protocol aims to maintain a high key rate for long-distance transmission under high noise.It has the potential to significantly broaden the application range of the continuous variable quantum key distribution protocol.The effects of amplifier parameters and noise on the modified protocol are analyzed in detail with regard to applying it to a practical system.To make the simulation more realistic,the effect of finite size on the new protocol is taken into account.It will serve as a guideline for the future use of hybrid linear amplifiers.Different parameters can be adjusted to achieve the best performance for key rates of different quantum channels. 展开更多
关键词 hybrid linear amplifier source-in-the-middle distribution finite-size analysis
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Piezomagnetic vibration energy harvester with an amplifier
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作者 João Pedro Norenberg Americo Cunha Jr +1 位作者 Piotr Wolszczak Grzegorz Litak 《Theoretical & Applied Mechanics Letters》 CAS CSCD 2023年第6期481-483,共3页
We study the effect of an amplification mechanism in a nonlinear vibration energy harvesting system where a ferromagnetic beam resonator is attached to the vibration source through an additional linear spring with a d... We study the effect of an amplification mechanism in a nonlinear vibration energy harvesting system where a ferromagnetic beam resonator is attached to the vibration source through an additional linear spring with a damper.The beam moves in the nonlinear double-well potential caused by interaction with two magnets.The piezoelectric patches with electrodes attached to the electrical circuit support mechanical energy transduction into electrical power.The results show that the additional spring can improve energy harvesting.By changing its stiffness,we observed various solutions.At the point of the optimal stiffness of the additional spring,the power output is amplified a few times depending on the excitation amplitude. 展开更多
关键词 Nonlinear energy harvesting PIEZOELECTRIC Displacement amplifier Bistable potential
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Research Towards Terahertz Power Amplifiers in Silicon-Based Process
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作者 CHEN Jixin ZHOU Peigen +3 位作者 YU Jiayang LI Zekun LI Huanbo PENG Lin 《ZTE Communications》 2023年第2期88-94,共7页
In view of the existing design challenges for Terahertz(THz)power amplifiers(PAs),the common design methods and the efforts of the State Key Laboratory of Millimeter Wave,Southeast University,China in the development ... In view of the existing design challenges for Terahertz(THz)power amplifiers(PAs),the common design methods and the efforts of the State Key Laboratory of Millimeter Wave,Southeast University,China in the development of silicon-based THz PAs,mainly including silicon-based PAs with operating frequencies covering 100–300 GHz,are summarized in this paper.Particularly,we design an LC-balun-based two-stage differential cascode PA with a center frequency of 150 GHz and an output power of 14 dBm.Based on a Marchand balun,we report a 220 GHz three-stage differential cascode PA with a saturated output power of 9.5 dBm.To further increase the output power of THz PA,based on a four-way differential power combining technique,we report a 211–263 GHz dual-LC-tank-based broadband PA with a recorded 14.7 dBm Psat and 16.4 dB peak gain.All the above circuits are designed in a standard 130 nm silicon germanium(SiGe)BiCMOS process. 展开更多
关键词 power amplifier power combining SIGE SILICON-BASED TERAHERTZ
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Vertical vibration control using nonlinear energy sink with inertial amplifier
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作者 Weixing ZHANG Wei ZHANG Xiangying GUO 《Applied Mathematics and Mechanics(English Edition)》 SCIE EI CSCD 2023年第10期1721-1738,共18页
To reduce additional mass, this work proposes a nonlinear energy sink(NES)with an inertial amplifier(NES-IA) to control the vertical vibration of the objects under harmonic and shock excitations. Moreover, this paper ... To reduce additional mass, this work proposes a nonlinear energy sink(NES)with an inertial amplifier(NES-IA) to control the vertical vibration of the objects under harmonic and shock excitations. Moreover, this paper constructs pure nonlinear stiffness without neglecting the gravity effect of the oscillator. Both analytical and numerical methods are used to evaluate the performance of the NES-IA. The research findings indicate that even if the actual mass is 1% of the main oscillator, the NES-IA with proper inertia angles and mass distribution ratios can still effectively attenuate the steady-state and transient responses of the main oscillator. Nonlinear stiffness and damping also have important effects. Due to strongly nonlinear factors, the coupled system may exhibit higher branch responses under harmonic excitation. In shock excitation environment, the NES-IA with a large dynamic mass can trigger energy capture of both main resonance and high-frequency resonance. Furthermore, the comparison with the traditional NES also confirms the advantages of the NES-IA in overcoming mass dependence. 展开更多
关键词 nonlinear energy sink(NES) vibration reduction inertial amplifier(IA) higher branch response high-frequency resonance
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HPA轴与围产期抑郁症状的研究进展
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作者 李星星 周梦佳 +5 位作者 刘李 肖归 张婷婷 张瑜 秦春香 陈正英 《护理学》 2024年第5期534-539,共6页
孕妇在围产期经历了一系列的生理和心理变化,这些变化可能导致下丘脑–垂体–肾上腺轴的激活和功能紊乱;皮质醇因能反映下丘脑–垂体–肾上腺轴功能,成为探索围产期抑郁症与下丘脑–垂体–肾上腺轴关系的重要生物标记物,因此,可通过探... 孕妇在围产期经历了一系列的生理和心理变化,这些变化可能导致下丘脑–垂体–肾上腺轴的激活和功能紊乱;皮质醇因能反映下丘脑–垂体–肾上腺轴功能,成为探索围产期抑郁症与下丘脑–垂体–肾上腺轴关系的重要生物标记物,因此,可通过探索皮质醇在围产期抑郁症状病因和病理生理学中的具体作用为其早期识别和疗效预测提供依据。本文就下丘脑–垂体–肾上腺轴与围产期抑郁症状的研究进展进行综述,旨在为国内相关研究设计和实施提供帮助。 展开更多
关键词 hpa 围产期抑郁症状 产前抑郁 产后抑郁
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自主跑轮运动对小鼠抑郁症与单胺神经递质及HPA轴的影响
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作者 张静 陈永芳 +1 位作者 黄晓燕 杨笑莹 《黑龙江科学》 2024年第6期85-87,92,共4页
为探究自主跑轮运动对小鼠抑郁症与单胺神经递质及下丘脑-垂体-肾上腺轴(HPA)的影响,选取40只C57BL/6J小鼠,随机分成对照组(10只)与抑郁症组(30只)。抑郁症组小鼠采用长期社会击败应激(CSDS)方法建立抑郁症模型,将建模成功的小鼠随机分... 为探究自主跑轮运动对小鼠抑郁症与单胺神经递质及下丘脑-垂体-肾上腺轴(HPA)的影响,选取40只C57BL/6J小鼠,随机分成对照组(10只)与抑郁症组(30只)。抑郁症组小鼠采用长期社会击败应激(CSDS)方法建立抑郁症模型,将建模成功的小鼠随机分成抑郁症组(10只)与抑郁症运动组(10只)。抑郁症运动组进行为期3周的自主跑轮运动后,通过旷场及悬尾测小鼠的焦虑样及抑郁样行为,高效液相色谱法测单胺神经递质的变化,酶联免疫吸附测定法测HPA轴的变化。结果表明,与抑郁症组相比,抑郁症运动组旷场中间区域时间百分比显著增加(P<0.05),悬尾不动时间显著减少(P<0.05);海马单胺神经递质中的5-羟色胺(5-HT)、去甲肾上腺素(NE)、多巴胺(DA)含量显著增加(P<0.05);血浆中的HPA轴的促肾上腺皮质激素释放激素(CRH)、促肾上腺皮质激素(ACTH)及皮质醇(CORT)含量显著下降(P<0.05)。说明自主跑轮运动对于抑郁症小鼠的焦虑及抑郁有改善作用,其作用机制可能与调节单胺神经递质水平及HPA轴功能有关。 展开更多
关键词 自主跑轮运动 长期社会击败应激 抑郁症 单胺神经递质 hpa
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基于HPG/HPA轴探讨疏肝化瘀法治疗肝郁血瘀型黄褐斑的机制
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作者 赵文杰 陈慧玲 +1 位作者 吴育婷 吴宇翔 《江西中医药大学学报》 2024年第1期41-44,共4页
目的:观察加味桃红四物汤联合珍珠五白面膜治疗对肝郁血瘀型黄褐斑患者HPG/HPA轴的影响,探讨疏肝化瘀法治疗黄褐斑的机制。方法:将90例肝郁血瘀型黄褐斑患者随机分为3组,各30例。基础治疗组予口服加味桃红四物汤治疗,对照组在基础治疗... 目的:观察加味桃红四物汤联合珍珠五白面膜治疗对肝郁血瘀型黄褐斑患者HPG/HPA轴的影响,探讨疏肝化瘀法治疗黄褐斑的机制。方法:将90例肝郁血瘀型黄褐斑患者随机分为3组,各30例。基础治疗组予口服加味桃红四物汤治疗,对照组在基础治疗组基础上联合外用氢醌乳膏,观察组在基础治疗组基础上联合外用珍珠五白面膜,3组治疗周期均为8周。对比3组患者治疗前后HPG/HPA轴相关激素水平的变化。结果:治疗后,3组患者LH、E2、FSH、MSH、CORT均下降(P<0.05),且观察组较基础治疗组、对照组改善显著(P<0.05)。结论:加味桃红四物汤联合珍珠五白面膜可明显降低肝郁血瘀型黄褐斑患者的LH、E2、FSH、MSH、CORT水平,提示疏肝化瘀法治疗黄褐斑的作用机制可能是通过调节HPG轴、HPA轴实现的。 展开更多
关键词 黄褐斑 肝郁血瘀 疏肝化瘀 桃红四物汤 珍珠五白散 HPG轴 hpa
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