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Analysis of Pulse Signals Based on Array Pulse Volume
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作者 CUI Ji TU Li-ping +3 位作者 ZHANG Jian-feng ZHANG Shao-liang ZHANG Zhi-feng XU Jia-tuo 《中国结合医学杂志:英文版》 SCIE CAS CSCD 2019年第2期103-107,共5页
Objective: To collect and analyze multi-dimensional pulse diagram features with the array sensor of a pressure profile system(PPS) and study the characteristic parameters of the new multi-dimensional pulse diagram by ... Objective: To collect and analyze multi-dimensional pulse diagram features with the array sensor of a pressure profile system(PPS) and study the characteristic parameters of the new multi-dimensional pulse diagram by pulse diagram analysis technology. Methods: The pulse signals at the Guan position of left wrist were acquired from 105 volunteers at the Shanghai University of Traditional Chinese Medicine. We obtained the pulse data using an array sensor with 3×4 channels. Three dimensional pulse diagrams were constructed for the validated pulse data, and the array pulse volume(APV) parameter was computed by a linear interpolation algorithm. The APV differences among normal pulse(NP), wiry pulse(WP) and slippery pulse(SP) were analyzed using one-way analysis of variance. The coefficients of variation(CV) were calculated for WP, SP and NP. Results: The APV difference between WP and NP in the 105 volunteers was statistically significant(6.26±0.28 vs. 6.04±0.36, P=0.048), as well as the difference between WP and SP(6.26±0.28 vs. 6.07±0.46, P=0.049). However, no statistically significant difference was found between NP and SP(P=0.75). WP showed a similar CV(4.47%) to those of NP(5.96%) and SP(7.58%). Conclusion: The new parameter APV could differentiate between NP or SP and WP. Accordingly, APV could be considered an useful parameter for the analysis of array pulse diagrams in Chinese medicine. 展开更多
关键词 PULSE SIGNAL ARRAY PULSE VOLUME PULSE SENSOR Chinese MEDICINE
A Gain-Switched Fe:ZnSe Laser Pumped by a Pulsed Ho,Pr:LLF Laser
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作者 李英一 鞠有伦 +3 位作者 戴通宇 段小明 郭春发 徐丽伟 《中国物理快报:英文版》 SCIE CAS CSCD 2019年第4期24-26,共3页
We demonstrate a gain-switched Fe:ZnSe laser pumped by a 2958 nm pulsed Ho,Pr:LLF laser. The maximum single pulse energy is 16.4uJ with a minimum pulse duration of 13.9 ns at the pulse repetition frequency of1 Hz when... We demonstrate a gain-switched Fe:ZnSe laser pumped by a 2958 nm pulsed Ho,Pr:LLF laser. The maximum single pulse energy is 16.4uJ with a minimum pulse duration of 13.9 ns at the pulse repetition frequency of1 Hz when the Fe:ZnSe crystal is cooled to 77 K by liquid nitrogen, corresponding to a slope efficiency of 22.9%.The central wavelength and FWHM linewidth are 3957.4 nm and 23.2 nm, respectively. The output energy monotonically decreases as the crystal temperature increases in the range 77–293 K. 展开更多
关键词 slope efficiency PULSE REPETITION frequency PULSE
Improving the data retention of phase change memory by using a doping element in selected Ge2Sb2Te5 预览
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作者 Yaoyao Lu Daolin Cai +5 位作者 Yifeng Chen Shuai Yan Lei Wu Yuanguang Liu Yang Li Zhitang Song 《半导体学报:英文版》 EI CAS CSCD 2019年第4期29-34,共6页
The crystallization characteristics of a ubiquitous T-shaped phase change memory (PCM) cell, under SET current pulse and very small disturb current pulse, have been investigated by finite element modelling. As analyze... The crystallization characteristics of a ubiquitous T-shaped phase change memory (PCM) cell, under SET current pulse and very small disturb current pulse, have been investigated by finite element modelling. As analyzed in this paper, the crystallization region under SET current pulse presents first on the corner of the bottom electron contact (BEC) and then promptly forms a filament shunting down the amorphous phase to achieve the low-resistance state, whereas the tiny disturb current pulse accelerates crystallization at the axis of symmetry in the phase change material. According to the different crystallization paths, a new structure of phase change material layer is proposed to improve the data retention for PCM without impeding SET operation. This structure only requires one or two additional process steps to dope nitrogen element in the center region of phase change material layer to increase the crystallization temperature in this confined region. The electrical-thermal characteristics of PCM cells with incremental doped radius have been analyzed and the best performance is presented when the doped radius is equal to the radius of the BEC. 展开更多
关键词 phase change memory CRYSTALLIZATION process SET CURRENT PULSE small disturb CURRENT PULSE finite ELEMENT simulation
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Field-free molecular orientation steered by combination of super-Gaussian and THz half-cycle laser pulses
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作者 程起元 宋玉志 孟庆田 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第11期150-155,共6页
The molecular orientation created by laser fields is important for steering chemical reactions. In this paper, we propose a theoretical scheme to manipulate field-free molecular orientation by using an intense super-G... The molecular orientation created by laser fields is important for steering chemical reactions. In this paper, we propose a theoretical scheme to manipulate field-free molecular orientation by using an intense super-Gaussian laser pulse and a time-delayed terahertz half-cycle pulse(THz HCP). It is shown that the degree of field-free orientation can be doubled by the combined pulse with respect to the super-Gaussian pulse or THz HCP alone. Moreover, different laser intensities, carrier envelop phases, shape parameters, and time delays have great influence on the positive and negative orientations, with other conditions unchanged. Furthermore, it is indicated that the maximum degree and direction of molecular orientation can be precisely controlled by half of the duration of the super-Gaussian pulse. Finally, by adjusting the laser parameters of the super-Gaussian laser pulse and THz HCP, the optimal results of negative orientation and corresponding rotational populations are obtained at different temperatures of the molecular system. 展开更多
关键词 molecular orientation TERAHERTZ half-cycle PULSE SUPER-GAUSSIAN PULSE
Analysis and optimization of high-power pulse transformer for SXFEL 预览
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作者 Yong-Fang Liu Hiroshi Matsumoto +3 位作者 Ming Gu Xiao-Xuan Zhou Yong-Hua Wu Zhi-Hao Chen 《核技术:英文版》 SCIE CAS CSCD 2019年第7期47-53,共7页
A C-band accelerator structure was used to accelerate electrons at the Shanghai soft X-ray free-electron laser test facility (SXFEL-TF) in Shanghai Institute of Applied Physics (SINAP). The microwave system of this ac... A C-band accelerator structure was used to accelerate electrons at the Shanghai soft X-ray free-electron laser test facility (SXFEL-TF) in Shanghai Institute of Applied Physics (SINAP). The microwave system of this accelerator structure used a 110 MW pulse modulator and a klystron (PV-5050) to provide the power supply. A pulse transformer is a crucial device in a modulator klystron system and plays significant roles in voltage level transformation, matching impedances, and polarity inversion. This study presents the optimization of a high-voltage pulse transformer. The design considerations of reducing flattop ringing and flattop droop, and shortening leading edge are provided. The model simulation, mechanical design, and the relevant experimental results are also presented. 展开更多
关键词 PULSE TRANSFORMER PULSE MODULATOR Flattop droop LEADING edge Flattop RINGING
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Nonlinear photoresponse of metallic graphene-like VSe2 ultrathin nanosheets for pulse laser generation
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作者 Tao WANG Xinyao SHI +10 位作者 Jin WANG Yijun XU Jie CHEN Zhuo DONG Man JIANG Pengfei MA Rongtao SU Yanxing MA Jian WU Kai ZHANG Pu ZHOU 《中国科学:信息科学(英文版)》 SCIE EI CSCD 2019年第12期131-138,共8页
Vanadium diselenide(VSe2), a typical metallic behaviour material among transition metal dichalcogenides(TMDCs) family, exhibits excellent photoelectric characteristics with a zero band gap, missing applicaiotn in puls... Vanadium diselenide(VSe2), a typical metallic behaviour material among transition metal dichalcogenides(TMDCs) family, exhibits excellent photoelectric characteristics with a zero band gap, missing applicaiotn in pulse generation. In this work, a high-quality VSe2 saturable absorber(SA) was synthesized through a liquid-phase exfoliation method. The saturable absorption of obtained VSe2-SA was characterized systematically. The measured modulation depth was 9.9%, and the saturated intensity was 533.8 μJ/cm2. By incorporating this optical modulator into a ytterbium-doped fiber laser cavity, a stable passively Q-switched laser could be achieved. The pulse had the central wavelength of 1064.03 nm. As the pump power was increased, the repetition rate increased from 24.3 k Hz to 35.6 k Hz, and the pulse duration decreased from7.21 μs to 5.27 μs. The output power had the maximum value of 28.55 m W. These results indicated that VSe2 is an effective candidate to generate pulse laser due to its excellent nonlinear optical properties and universal photoelectric response, which may advance the applications of VSe2-based nonlinear optics and photoelectric devices. 展开更多
关键词 transition metal dichalcogenides VSe2 saturable absorber pulse laser fiber laser
朱利安·巴恩斯短篇小说的历史叙事分析 预览
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作者 赵胜杰 任娜 《山西高等学校社会科学学报》 2019年第11期93-97,共5页
在发表于千禧年之后的短篇小说集《柠檬桌子》与《脉搏》中,步入晚年的朱利安·巴恩斯将写作的笔触更多地聚焦人生感悟。与此同时,他延续了早期作品中对历史主题的关注,主要采用了叙事越界、戏仿传记和文类拼贴等后现代主义的写作手... 在发表于千禧年之后的短篇小说集《柠檬桌子》与《脉搏》中,步入晚年的朱利安·巴恩斯将写作的笔触更多地聚焦人生感悟。与此同时,他延续了早期作品中对历史主题的关注,主要采用了叙事越界、戏仿传记和文类拼贴等后现代主义的写作手法,希冀读者借由历史人物反观现实生活。通过这些叙事技巧,一方面,作者表达了自我的历史观:历史是众声喧哗、颠覆严肃并且由诸多零散片段组合而成的;另一方面,巴恩斯又试图引导读者跨越历史而反观自我、烛照内心,表现借古鉴今的深刻意味。 展开更多
关键词 朱利安•巴恩斯 《柠檬桌子》 《脉搏》 历史叙事
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Femtosecond strong-field coherent control of nonresonant ionization with shaped pulses
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作者 佟秋男 廉振中 +3 位作者 赵亮 齐洪霞 陈洲 胡湛 《中国物理B:英文版》 SCIE EI CAS CSCD 2019年第3期153-160,共8页
The strong-field coherent control of the nonresonant ionization of nitrous oxide using shaped pulses is investigated.We study the dependence of periodic coherent oscillation of the total ionization yield on the variat... The strong-field coherent control of the nonresonant ionization of nitrous oxide using shaped pulses is investigated.We study the dependence of periodic coherent oscillation of the total ionization yield on the variation of laser phase parameters. The physical mechanism of the strong-field coherent control is investigated experimentally and theoretically by the nonresonant spectral phase interferences in the frequency domain. We show that the intense shaped pulses with broadband and off-resonance can be used as a robust strong-field coherent control method. 展开更多
关键词 COHERENT control nonresonant IONIZATION SHAPED PULSE
ReSe2 as a saturable absorber in a Tm-doped yttrium lithium fluoride(Tm:YLF) pulse laser
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作者 李春 冷雨欣 霍金金 《中国光学快报:英文版》 SCIE EI CAS CSCD 2019年第1期62-65,共4页
This study investigates the applicability of a few-layer structure ReSe2 as a saturable absorber(SA) for demonstrating a passively Q-switched pulse laser. The ReSe2 SA had a modulation depth of 6.86%. The Q-switched e... This study investigates the applicability of a few-layer structure ReSe2 as a saturable absorber(SA) for demonstrating a passively Q-switched pulse laser. The ReSe2 SA had a modulation depth of 6.86%. The Q-switched experiment was successful in delivering a maximum average output power of 180 mW at the wavelength of1906.5 nm. The optimal pulse train had a pulse width of 1.61 μs and a repetition rate of 28.78 kHz. The experiment results verify that the few-layer structure ReSe2 could behave as an excellent SA at all-solid-state lasers, increasing the selection of SAs at near 2 μm lasers. 展开更多
关键词 SA Tm:YLF PULSE LASER
正色散光纤激光器中矩形耗散孤子与高斯光谱脉冲的切换锁模 预览
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作者 李静玲 韩冬冬(指导) +6 位作者 惠战强 任凯利 罗文峰 姚英 赵峰 忻向军 巩稼民 《光子学报》 EI CAS CSCD 北大核心 2019年第5期146-152,共7页
基于单壁碳纳米管与非线性偏振旋转技术在锁模光纤激光器中仿真和实验观测到矩形耗散孤子与高斯光谱脉冲的切换锁模.矩形耗散孤子的光谱与脉冲宽度分别为~6.33ps和~12.54nm,具有非常强的啁啾.适当地调节偏振控制器,可以获得具有高斯型... 基于单壁碳纳米管与非线性偏振旋转技术在锁模光纤激光器中仿真和实验观测到矩形耗散孤子与高斯光谱脉冲的切换锁模.矩形耗散孤子的光谱与脉冲宽度分别为~6.33ps和~12.54nm,具有非常强的啁啾.适当地调节偏振控制器,可以获得具有高斯型光谱和脉冲的锁模状态,其光谱和脉冲宽度分别为~1.87ps和~2.2nm.高斯型光谱脉冲的时间带宽积为0.51,几乎没有啁啾.不同锁模状态间的切换归因于偏振控制器导致的腔内偏振的改变. 展开更多
关键词 光纤激光器 耗散孤子 开关锁模 脉冲 色散 啁啾
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高速编码器在流量计量中的应用 预览
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作者 杨智 裴锐 《仪器仪表用户》 2019年第9期45-47,共3页
详细分析的X2控制器用于高速IO测量的4种测量方式:累加计数、正交计数、频率计数和脉宽计数.通过对X2控制器编程实现了欧姆龙编码器累积脉冲、旋转方向、旋转圈数的计量,进而验证了高速编码器用于工业流量计量的可行性.工业编码器可靠性... 详细分析的X2控制器用于高速IO测量的4种测量方式:累加计数、正交计数、频率计数和脉宽计数.通过对X2控制器编程实现了欧姆龙编码器累积脉冲、旋转方向、旋转圈数的计量,进而验证了高速编码器用于工业流量计量的可行性.工业编码器可靠性强,应用灵活,可以有效地提升容积式流量计的现场计量效率. 展开更多
关键词 编码器 X2控制器 累积 频率 正交 脉冲
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Detection of small delamination in mullite/Si/SiC model EBC system by pulse thermography
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作者 Yutaro ARAI Ryo INOUE 《先进陶瓷(英文版)》 CSCD 2019年第3期438-447,共10页
The pulse thermography(PT) technique was applied to the detection of the delamination of a multi-layered coating system composed of mullite/Si onto a reaction-bonded Si C substrate. The potential evaluation was carrie... The pulse thermography(PT) technique was applied to the detection of the delamination of a multi-layered coating system composed of mullite/Si onto a reaction-bonded Si C substrate. The potential evaluation was carried out in order to detect internal delamination in multi-layered material system. Moreover, the observation of the cross sections and 3D views obtained by X-ray computed tomography(CT) indicated that the delamination occurred at the interface between the top coat and the bond coat layers. The changes in the temperature distribution obtained by PT indicated the existence of a delamination area in the top coat layer of the mullite. In particular, the lower temperature region corresponded to the delamination area. The experimental results confirmed that the PT technique is effective with respect to the internal delamination of multi-layered coating system. 展开更多
关键词 environmental BARRIER coatings (EBCs) DELAMINATION pulse THERMOGRAPHY (PT) MULTI-LAYER image processing
中小学生不同营养指数的年龄曲线特征及其与血压脉搏相关性分析
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作者 沙汝明 《中国校医》 2019年第5期329-330,391共3页
目的明确中小学生不同营养指数的年龄曲线特征及其与血压脉搏相关性。方法应用SPSS软件对2017年苏州市中小学生体检结果进行统计分析,分析不同年龄营养指数(BMI、Quetelet、Rohrer)均数,观察不同营养指数的年龄曲线特征;通过不同营养指... 目的明确中小学生不同营养指数的年龄曲线特征及其与血压脉搏相关性。方法应用SPSS软件对2017年苏州市中小学生体检结果进行统计分析,分析不同年龄营养指数(BMI、Quetelet、Rohrer)均数,观察不同营养指数的年龄曲线特征;通过不同营养指数与血压脉搏的相关分析,观察其关联度。结果 BMI、Quetelet指数均值随年龄增长而上升;Rohrer指数均值6岁开始随年龄增长而下降,低点在13岁,14开始随年龄增长而上升,呈"V"型走势。身高体质量及不同营养指数与血压皆呈正相关(P<0.01),BMI、Quetelet指数与脉搏负相关(P<0.01),Rohrer指数与脉搏正相关(P<0.01)。结论 BMI、Quetelet指数的年龄曲线特征与经典描述一致,Rohrer指数的年龄曲线特征与经典描述不一致。超重肥胖是高血压危险因素,不同营养指数与血压皆呈正相关(收缩压比舒张压关联度更高),其关联度由高到低排列为:Quetelet、BMI、Rohrer。不同营养指数与脉搏相关分析结果不一致。 展开更多
关键词 营养状况 血压 脉搏
脉搏波传导速度在心血管疾病诊疗中的研究进展
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作者 曾祥辉 赖珩莉 罗建平 《中国基层医药》 CAS 2019年第16期2045-2048,共4页
心血管疾病已成为老年人群最常见、患病率最高的慢性疾病,吸烟、高血脂、糖尿病等高危因素通过损伤血管壁的结构和功能,参与动脉粥样硬化的发生、发展,相应出现动脉僵硬。脉搏波传导速度(PWV)是指脉搏波由动脉的一特定位置沿管壁传播至... 心血管疾病已成为老年人群最常见、患病率最高的慢性疾病,吸烟、高血脂、糖尿病等高危因素通过损伤血管壁的结构和功能,参与动脉粥样硬化的发生、发展,相应出现动脉僵硬。脉搏波传导速度(PWV)是指脉搏波由动脉的一特定位置沿管壁传播至另一特定的位置的速率,是评估动脉弹性和血管功能变化的简捷、有效且可重复的非侵入性指标。PWV与心血管疾病密切相关,近年来,对PWV与心血管疾病关系已有较深入的研究。本研究主要从PWV与冠心病、高血压、心功能、心房颤动、肺动脉高压五个方面的关系加以综述。 展开更多
关键词 脉搏 心脏传导系统 动脉粥样硬化 冠状动脉疾病 高血压 心脏功能试验 心房颤动 高血压 肺性 综述
臂踝脉搏波传导速度对急性缺血性脑卒中早期预后的预测价值 预览
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作者 蔡涵璐 王丽华 +1 位作者 刘佩芳 吴云 《心血管康复医学杂志》 CAS 2019年第4期517-519,共3页
大量研究表明臂踝脉搏波传导速度(baPWV)与大动脉的硬化程度密切相关,已被广泛应用于评估动脉粥样硬化程度。有证据表明baPWV是心血管事件发生和死亡的独立预测因子。但目前国内外对baPWV与急性缺血性卒中相关性的研究较少,本文旨在阐述... 大量研究表明臂踝脉搏波传导速度(baPWV)与大动脉的硬化程度密切相关,已被广泛应用于评估动脉粥样硬化程度。有证据表明baPWV是心血管事件发生和死亡的独立预测因子。但目前国内外对baPWV与急性缺血性卒中相关性的研究较少,本文旨在阐述baPWV对急性缺血性脑卒中患者早期预后的预测价值。 展开更多
关键词 脑卒 动脉粥样硬化 脉搏
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Enhancement of optical emission generated from femtosecond double-pulse laser-induced glass plasma at different sample temperatures in air
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作者 王莹 陈安民 +5 位作者 王秋云 张丹 隋来志 李苏宇 姜远飞 金明星 《等离子体科学与技术:英文版》 SCIE EI CAS CSCD 2019年第3期98-107,共10页
In double-pulse laser-induced breakdown spectroscopy(DP-LIBS),the collinear femtosecond double-pulse laser configuration is experimentally investigated with different initial sample temperatures using a Ti:sapphire la... In double-pulse laser-induced breakdown spectroscopy(DP-LIBS),the collinear femtosecond double-pulse laser configuration is experimentally investigated with different initial sample temperatures using a Ti:sapphire laser.The glass sample is ablated to produce the plasma spectroscopy.During the experiment,the detected spectral lines include two Na(I)lines(589.0 nm and 589.6 nm)and one Ca(I)line at the wavelength of 585.7 nm.The emission lines are measured at room temperature(22°C)and three higher initial sample temperatures(Ts=100°C,200°C,and 250°C).The inter-pulse delay time ranges from-250 ps to 250 ps.The inter-pulse delay time and the sample temperature strongly influence the spectral intensity,and the spectral intensity can be significantly enhanced by increasing the sample temperature and selecting the optimized inter-pulse time.For the same inter-pulse time of 0ps(single-pulse LIBS),the enhancement ratio is approximately 2.5 at Ts=200°C compared with that obtained at Ts=22°C.For the same inter-pulse time of 150 ps,the enhancement ratio can be up to 4 at Ts=200°C compared with that obtained at Ts=22°C.The combined enhancement effects of the different initial sample temperatures and the double-pulse configuration in femtosecond LIBS are much stronger than that of the different initial sample temperatures or the double-pulse configuration only. 展开更多
关键词 LASER-INDUCED BREAKDOWN spectroscopy FEMTOSECOND laser double pulse emission ENHANCEMENT GLASS
雷达散射计低噪声脉冲行波管放大器电源研制 预览
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作者 张军 梁英 +3 位作者 路小月 王勇 樊经纬 范传强 《真空电子技术》 2019年第4期55-60,共6页
本文提出并实现了一种降低脉冲行波管放大器噪声的设计方案,解决了深空探测脉冲行波管放大器一直存在的阴极纹波噪声大、脉内及脉间噪声功率谱密度较差、低重频脉宽调制难以实现等技术难点。该方案首先利用脉宽调制(PWM)技术控制的有源... 本文提出并实现了一种降低脉冲行波管放大器噪声的设计方案,解决了深空探测脉冲行波管放大器一直存在的阴极纹波噪声大、脉内及脉间噪声功率谱密度较差、低重频脉宽调制难以实现等技术难点。该方案首先利用脉宽调制(PWM)技术控制的有源滤波器来降低卫星母线脉冲电流波动,进而减小电流对器件的冲击延长使用寿命;其次在升压电路后级使用基于比例积分微分(PID)调节的线性稳压器,来进一步地减小阴极纹波噪声;调制器电路使用多级悬浮调制器隔离技术及展频电路,实现降低纹波噪声和低重频脉宽调制的功能。基于以上设计,实现了脉冲行波管放大器噪声功率谱密度低于-90 dBm/Hz,产品杂波抑制度低于-75 dBc。将其用于相关型号散射计分系统的鉴定与验收试验,相关性能指标达到了国际水平,实现风速测量优于1.8 m/s的指标,成为国内首台空间应用的高可靠、长寿命脉冲行波管放大器。 展开更多
关键词 雷达 行波管 脉冲 高压 长寿命 可靠性
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A modified pulse charging method for lithium-ion batteries by considering stress evolution,charging time and capacity utilization
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作者 Yanfei ZHAO Bo LU +1 位作者 Yicheng SONG Junqian ZHANG 《结构与土木工程前沿:英文版》 EI CSCD 2019年第2期294-302,共9页
The stress evolution, total charging time and capacity utilization of pulse charging (PC) method are investigated in this pape匚 It is found that compared to the conventional constant current (CC) charging method, the... The stress evolution, total charging time and capacity utilization of pulse charging (PC) method are investigated in this pape匚 It is found that compared to the conventional constant current (CC) charging method, the PC method can accelerate the charging process but will inevitably cause an increase in stress and a decrease in capacity. The charging speed for PC method can be estimated by the mean current. By introducing stress control, a modified PC method called the PCCC method, which starts with a PC operation followed by a CC operation, is proposed. The PCCC method not only can accelerate charging process but also can avoid the stress raising and capacity loss occurring in the PC method. Furthermore, the optimal pulsed current density and switch time in the PCCC method is also discussed. 展开更多
关键词 fast CHARGING METHOD PULSE CHARGING stress evolution CHARGING time capacity UTILIZATION
高血压患者主动脉脉搏波传导速度影响因素探究 预览
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作者 田松枚 冯六六 +1 位作者 黄红漫 肖文颖 《心血管康复医学杂志》 CAS 2019年第3期315-317,共3页
目的:分析原发性高血压(EH)患者主动脉脉搏波传导速度(APWV)的影响因素。方法:我院336例EH患者被分为APWV升高组(281例)和APWV正常组(55例),对比两组临床资料,采用Logistic多元回归分析EH患者APWV的影响因素。结果:与APWV正常组比较,APW... 目的:分析原发性高血压(EH)患者主动脉脉搏波传导速度(APWV)的影响因素。方法:我院336例EH患者被分为APWV升高组(281例)和APWV正常组(55例),对比两组临床资料,采用Logistic多元回归分析EH患者APWV的影响因素。结果:与APWV正常组比较,APWV升高组年龄[(56.71±11.45)岁比(62.98±12.36)岁],糖尿病(5.45%比19.22%)、肥胖(18.18%比23.84%)、吸烟史(16.36%比30.60%)、高血压3级(12.73%比32.03%)比例,人体质量指数(BMI)[(22.53±2.07)kg/m2比(23.28±2.04)kg/m2],SBP[(139.64±12.85)mmHg比(147.39±13.30)mmHg]、DBP[(93.18±8.73)mmHg比(96.43±9.14)mmHg],TC[(5.18±0.91)mmol/L比(5.65±1.03)mmol/L]、LDL-C[(3.00±0.68)mmol/L比(3.24±0.72)mmol/L]、SCr[(110.71±52.39)μmol/L比(138.52±63.65)μmol/L]、SUA[(318.73±102.62)μmol/L比(354.28±108.35)μmol/L]水平显著升高,HDL-C(1.19±0.32)mmol/L比(1.09±0.30)mmol/L显著降低(P<0.05或<0.01)。多因素Logistic回归分析显示,年龄、糖尿病、SBP、TC、SCr、高血压等级是影响APWV的独立危险因素(OR=2.826~3.732,P均<0.05)。结论:年龄、糖尿病、SBP、TC、SCr、高血压等级是影响原发性高血压患者APWV的危险因素,因此,应采取相应的防治措施改善预后。 展开更多
关键词 高血压 脉搏 危险因素
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砂岩油藏注水井脉冲式在线注入酸化增注技术 预览 被引量:1
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作者 张彩虹 杨乾隆 +1 位作者 李发旺 贺耀 《钻井液与完井液》 CAS 北大核心 2019年第2期261-264,共4页
注水是实现油田长期稳产和高效开发的关键技术。受储层物性及注入水水质等因素的影响,华庆油田部分区块注水压力逐渐上升,高压欠注井越来越多,而目前现有的酸化增注技术暴露出有效期短、多次酸化增注低效、措施占井周期长、设备动迁困... 注水是实现油田长期稳产和高效开发的关键技术。受储层物性及注入水水质等因素的影响,华庆油田部分区块注水压力逐渐上升,高压欠注井越来越多,而目前现有的酸化增注技术暴露出有效期短、多次酸化增注低效、措施占井周期长、设备动迁困难、作业成本攀升等问题。针对以上问题,结合目标区块储层特征,通过大量室内实验调试对比,将常规六齿氨基羧酸螯合剂配位键升到八位,形成八齿螯合剂,增强了对金属离子的捕获、螯合、包裹作用,通过酸液复配,优选出一种适合目标储层的酸液体系;与此同时加强设备优化改进,添加远程操作系统,提高精准度;通过地面配套脉冲式柱塞泵注程序,形成了注水井脉冲式在线注入酸化增注技术。截至目前现场应用4井次,措施后平均单井注水压力下降9.0 MPa,单井日增注14.0 m3,平均有效期已达182 d,降压增注效果显著,有效期长;同时该技术解决了占井周期长、设备动迁困难等问题,现场操作简便,建议推广应用。 展开更多
关键词 注水井 高压欠注 降压增注 脉冲 在线酸化 COA-1S酸液体系
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