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Anomalous Direct-Current Josephson Effect in Semiconductor Nanowire Junctions
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作者 伍滨和 封许昱 +2 位作者 王超 徐晓峰 王春瑞 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第1期118-122,共5页
We investigate the dc Josephson effect in one-dimensional junctions where a ring conductor is sandwiched between two semiconductor nanowires with proximity-induced superconductivity. Peculiar features of the Josephson... We investigate the dc Josephson effect in one-dimensional junctions where a ring conductor is sandwiched between two semiconductor nanowires with proximity-induced superconductivity. Peculiar features of the Josephson effect arise due to the interplay of spin-orbit interaction and external Zeenmn field. By tuning the Zeeman field orientation, the device can vary from 0 to π junction. Afore importantly, nonzero ,losephson current is possible at zero phase difference across the junction. Although this anomalous Josephson current is not relevant to the topological phase transition, its magnitude can be significantly enhanced whe, n the nanowire, s become topological superconductors where Majorana bound states emerge. Distinct modulation patterns are obtained for the semiconductor nanowires in the topologically trivial and non-trivial phases. These results are useful to probe the topological phase transition in semiconductor nanowire junctions via the dc Josephson effect. 展开更多
关键词 of IS on in for Anomalous direct-current Josephson Effect in Semiconductor Nanowire Junctions SOI
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Effects of the sputtering power on the crystalline structure and optical properties of the silver oxide films deposited using direct-current reactive magnetron sputtering
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作者 郜小勇 张增院 +3 位作者 马姣民 卢景霄 谷锦华 杨仕娥 《Chinese Physics B》 SCIE EI CAS CSCD 2011年第2期370-375,共6页
This paper reports that a series of silver oxide (AgzO) films are deposited on glass substrates by direct-current reactive magnetron sputtering at a substrate temperature of 250 ℃ and an oxygen flux ratio of 15:18... This paper reports that a series of silver oxide (AgzO) films are deposited on glass substrates by direct-current reactive magnetron sputtering at a substrate temperature of 250 ℃ and an oxygen flux ratio of 15:18 by modifying the sputtering power (SP). The AgxO films deposited apparently show a structural evolution from cubic biphased (AgO + Ag20) to cubic single-phased (Ag20), and to biphased (Ag20 + AgO) structure. Notably, the cubic single-phased Ag20 fihn is deposited at the SP = 105 W and an AgO phase with (220) orientation discerned in the Ag^O films deposited using the SP 〉 105 W. The transmissivity and refiectivity of the AgxO films in transparent region decrease with the increase the SP, whereas the absorptivity inversely increases with the increase of the SP. These results may be due to the structural evolution and the increasing film thickness. A redshift of the films' absorption edges determined in terms of Tauc formula clearly occurs from 3.1 eV to 2.73 eV with the increase of the SP. 展开更多
关键词 Ag2O film direct-current reactive magnetron sputtering x-ray diffraction optical prop-erties
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Structural,Morphological and Electrical Properties of In-Doped Zinc Oxide Nanostructure Thin Films Grown on p-Type Gallium Nitride by Simultaneous Radio-Frequency Direct-Current Magnetron Co-Sputtering
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作者 R.Perumal Z.Hassan R.Saravanan 《Chinese Physics Letters》 SCIE CAS CSCD 2016年第6期77-80,共4页
Zinc oxide (ZnO) is one of the most promising and frequently used semiconductor materials. In-doped nanos- tructure ZnO thin films are grown on p-type gallium nitride substrates by employing the simultaneous rf and ... Zinc oxide (ZnO) is one of the most promising and frequently used semiconductor materials. In-doped nanos- tructure ZnO thin films are grown on p-type gallium nitride substrates by employing the simultaneous rf and dc magnetron co-sputtering technique. The effect of In-doping on structural, morphological and electrical properties is studied. The different dopant concentrations are accomplished by varying the direct current power of the In target while keeping the fixed radio frequency power of the ZnO target through the co-sputtering deposition technique by using argon as the sputtering gas at ambient temperature. The structural analysis confirms that all the grown thin films preferentially orientate along the c-axis with the wurtzite hexagonal crystal structure without having any kind of In oxide phases. The presenting Zn, 0 and In elements' chemical compositions are identified with EDX mapping analysis of the deposited thin films and the calculated M ratio has been found to decrease with the increasing In power. The surface topographies of the grown thin films are examined with the atomic force microscope technique. The obtained results reveal that the grown film roughness increases with the In power. The Hall measurements ascertain that all the grown films have n-type conductivity and also the other electrical parameters such as resistivity,mobility and carrier concentration are analyzed. 展开更多
关键词 ZnO of Structural Morphological and Electrical Properties of In-Doped Zinc Oxide Nanostructure Thin Films Grown on p-Type Gallium Nitride by Simultaneous Radio-Frequency direct-current Magnetron Co-Sputtering that by were been In EDX on
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Bidirectional rotating direct-current triboelectric nanogenerator with self-adaptive mechanical switching for harvesting reciprocating motion
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作者 Donghan Lee Joonmin Chae +6 位作者 Sumin Cho Jong Woo Kim Awais Ahmad Mohammad Rezaul Karim Moonwoo La Sung Jea Park Dongwhi Choi 《International Journal of Extreme Manufacturing》 SCIE EI CAS CSCD 2024年第4期324-335,共12页
Amid the growing interest in triboelectric nanogenerators(TENGs)as novel energy-harvesting devices,several studies have focused on direct current(DC)TENGs to generate a stable DC output for operating electronic device... Amid the growing interest in triboelectric nanogenerators(TENGs)as novel energy-harvesting devices,several studies have focused on direct current(DC)TENGs to generate a stable DC output for operating electronic devices.However,owing to the working mechanisms of conventional DC TENGs,generating a stable DC output from reciprocating motion remains a challenge.Accordingly,we propose a bidirectional rotating DC TENG(BiR-TENG),which can generate DC outputs,regardless of the direction of rotation,from reciprocating motions.The distinct design of the BiR-TENG enables the mechanical rectification of the alternating current output into a rotational-direction-dependent DC output.Furthermore,it allows the conversion of the rotational-direction-dependent DC output into a unidirectional DC output by adapting the configurations depending on the rotational direction.Owing to these tailored design strategies and subsequent optimizations,the BiR-TENG could generate an effective unidirectional DC output.Applications of the BiR-TENG for the reciprocating motions of swinging doors and waves were demonstrated by harnessing this output.This study demonstrates the potential of the BiR-TENG design strategy as an effective and versatile solution for energy harvesting from reciprocating motions,highlighting the suitability of DC outputs as an energy source for electronic devices. 展开更多
关键词 direct-current triboelectric nanogenerator mechanical rectification self-adaptive mechanical design harvesting reciprocation motion
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Analyses of nonequilibrium transport in atmospheric-pressure direct-current argon discharge under different modes
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作者 Ziming ZHANG Chuan FANG +2 位作者 Yaoting WANG Lanyue LUO Heping LI 《Plasma Science and Technology》 SCIE EI CAS CSCD 2024年第11期107-126,共20页
The key plasma parameters under different discharge modes, such as heavy-particle and electron temperatures, electron number density, and nonequilibrium volume of plasmas, play important roles in various applications ... The key plasma parameters under different discharge modes, such as heavy-particle and electron temperatures, electron number density, and nonequilibrium volume of plasmas, play important roles in various applications of gas discharge plasmas. In this study, a self-consistent two-dimensional nonequilibrium fluid model coupled with an external circuit model is established to reveal the mechanisms related to the discharge modes, including the normal glow, abnormal glow,arc, and glow-to-arc transition modes, with an atmospheric-pressure direct-current(DC) argon discharge as a model plasma system. The modeling results show that, under different discharge modes, the most significant difference between the preceding four discharge modes lies in the current and energy transfer processes on the cathode side. On one hand, the current to the cathode surface is mainly delivered by the ions coming from the plasma column under the glow discharge mode due to the low temperature of the solid cathode, whereas the thermionic and secondary electrons emitted from the hot cathode surface play a very important role under the arc mode with a higher cathode surface temperature and higher ion flux toward the cathode. On the other hand, the energy transfer channel on the cathode side changes from mainly heating the solid cathode under the glow mode to simultaneously heating both the solid cathode and plasma column under the arc mode with an increase in the discharge current. Consequently, the power density in the cathode sheath(P_c) was used as a key parameter for judging different discharge modes, and the range of(0.28–1.2) × 10^(12) W m^(-3) was determined as a critical window of P_c corresponding to the glow-to-arc-mode transition for the atmospheric-pressure DC argon discharge, which was also verified by comparison with the experimental results in this study and the data in the previous literature. 展开更多
关键词 atmospheric-pressure plasma direct-current gas discharge discharge mode mode transition power density in cathode sheath
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Modeling of Pulsed Direct-Current Glow Discharge
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作者 杜木 郑亚茹 +3 位作者 范宇佳 张楠 刘成森 王德真 《Plasma Science and Technology》 SCIE EI CAS CSCD 2010年第4期447-451,共5页
A self-consistent model was adopted to study the time evolution of low-voltage pulsed DC glow discharge. The distributions of electric field, ion density and electron density in nitrogen were investigated in our simul... A self-consistent model was adopted to study the time evolution of low-voltage pulsed DC glow discharge. The distributions of electric field, ion density and electron density in nitrogen were investigated in our simulation, and the temporal shape of the discharge current was also obtained. Our results show that the dynamic behaviors of the discharge depends strongly on the applied pulse voltage, and the use of higher pulse voltages results in a significantly increase of discharge current and a decrease of discharge delay time. The current-voltage characteristic cMculated by adjusting secondary electron emission coefficient for different applied pulse voltage under the gas pressure of 1 Torr is found in a reasonable agreement with the experimental results. 展开更多
关键词 pulsed direct-current glow discharge plasma processing plasma simulation
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Research on corona discharge suppression of high-voltage direct-current transmission lines based on dielectric-film-covered conductor
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作者 Yuze JIANG Qiying LI +4 位作者 Xuekai ZHANG Diwen JIANG Shiqiang LIU Bangfa PENG Jie LI 《Plasma Science and Technology》 SCIE EI CAS CSCD 2021年第2期64-75,共12页
Corona discharge suppression for high-voltage direct-current(HVDC)transmission lines at line terminals such as converter stations is a subject that requires attention.In this paper,a method based on a conductor covere... Corona discharge suppression for high-voltage direct-current(HVDC)transmission lines at line terminals such as converter stations is a subject that requires attention.In this paper,a method based on a conductor covered with dielectric film is proposed and implemented through a bench-scale setup.Compared with the bare conductor,the corona discharge suppression effect of the dielectric-film-covered conductor under positive polarity is studied from the composite field strength and ion current density using a line-plate experimental device.The influences of film thickness and film material on the corona discharge suppression effect are investigated.The charge accumulation and dissipation characteristics of different film materials are also studied.The results show that the conductor covered with dielectric film has excellent ability to inhibit corona discharge.The ground-level composite field strength of the conductor covered with dielectric film is lower than its nominal field strength,and its ion current density is at the nA m^(−2) level.The corona threshold voltage can be promoted by increasing the film thickness,but the ability to inhibit corona discharge becomes weak.The larger the surface electric field strength,the more charge accumulated,but the faster the charge dissipation rate.Compared with polyvinyl chloride film,cross-linked polyethylene film has stronger charge accumulation ability and slower charge dissipation rate,which can better restrain the corona discharge of HVDC transmission lines. 展开更多
关键词 high-voltage direct-current(HVDC)transmission lines corona discharge suppression dielectric-film-covered conductor composite field strength ion current density
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Three modes of a direct-current plasma jet operated underwater to degrade methylene blue 被引量:5
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作者 Xuechen LI Biao WANG +3 位作者 Pengying JIA Linwei YANG Yaru LI Jingdi CHU 《Plasma Science and Technology》 SCIE EI CAS CSCD 2017年第11期75-81,共7页
A direct-current air plasma jet operated underwater presents three stable modes including an intermittently-pulsed discharge, a periodically-pulsed discharge and a continuous discharge with increasing the power voltag... A direct-current air plasma jet operated underwater presents three stable modes including an intermittently-pulsed discharge, a periodically-pulsed discharge and a continuous discharge with increasing the power voltage. The three discharge modes have different appearances for the plasma plumes. Moreover, gap voltage-current characteristics indicate that the continuous discharge is in a normal glow regime. Spectral lines from reactive species(OH, N2, N2^+, Hα,and O) have been revealed in the emission spectrum of the plasma jet operated underwater.Spectral intensities emitted from OH radical and oxygen atom increase with increasing the power voltage or the gas flow rate, indicating that reactive species are abundant. These reactive species cause the degradation of the methylene blue dye in solution. Effects of the experimental parameters such as the power voltage, the gas flow rate and the treatment time are investigated on the degradation efficiency. Results indicate that the degradation efficiency increases with increasing the power voltage, the gas flow rate or the treatment time. Compared with degradation in the intermittently-pulsed mode or the periodically-pulsed one, it is more efficient in the continuous mode, reaching 98% after 21 min treatment. 展开更多
关键词 plasma jet direct current glow discharge plasma degradation methylene blue
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Intelligent algorithm-based maximum power point tracker for an off-grid photovoltaic-powered direct-current irrigation system 被引量:1
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作者 Hussain Attia Maen Takruri Ali Al-Ataby 《Clean Energy》 EI CSCD 2024年第3期48-61,共14页
This research aims to enhance the performance of photovoltaic(PV)systems on a 2-fold basis.Firstly,it introduces an advanced deep artificial neural network algorithm for accurate and fast maximum power point tracking,... This research aims to enhance the performance of photovoltaic(PV)systems on a 2-fold basis.Firstly,it introduces an advanced deep artificial neural network algorithm for accurate and fast maximum power point tracking,ensuring optimal extraction of electrical power from PV arrays.Secondly,it proposes the use of 96-V,2.98-kW direct-current(DC)water pumps for farm irrigation,aiming to improve efficiency,reduce cost and complexity,and overcome challenges associated with connecting faraway farm irrigation systems to the utility grid.In this study,it has been demonstrated that the use of DC pumps greatly improves system performance and efficiency by eliminating the need for isolation transformers,power passive filters and inverters,therefore simplifying the architecture of the system.The efficacy of the proposed methodology is confirmed by MATLAB®/Simulink®simulation results,whereby the proposed algorithm attains a mean squared error of 6.5705×10^(-5)and a system efficiency approaching 99.8%,ensuring a steady voltage under varying load conditions. 展开更多
关键词 artificial neural network photovoltaic arrays maximum power point tracking buck converter direct-current irrigation systems MATLAB/SIMULINK
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经颅直流电刺激干预后非稳定杠铃卧推运动表现及肌电活动变化
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作者 王乐军 池雯欣 +3 位作者 宋筱倩 李倩 乔敏洁 陶海峰 《中国组织工程研究》 北大核心 2026年第23期6099-6109,共11页
背景:经颅直流电刺激可以通过调节大脑皮质兴奋性提高人体运动表现,但其对非稳定负荷运动任务表现的影响仍不明确。目的:探讨经颅直流电刺激对非稳定杠铃卧推运动表现及肌电活动的影响。方法:采用随机、自身对照交叉试验设计,22名男性... 背景:经颅直流电刺激可以通过调节大脑皮质兴奋性提高人体运动表现,但其对非稳定负荷运动任务表现的影响仍不明确。目的:探讨经颅直流电刺激对非稳定杠铃卧推运动表现及肌电活动的影响。方法:采用随机、自身对照交叉试验设计,22名男性大学生受试者接受随机的真刺激(阳极刺激)和假刺激2种经颅直流电刺激干预,分别在经颅直流电刺激干预后对受试者进行非稳定杠铃卧推疲劳试验,记录完成卧推动作的次数和卧推运动中杠铃杆的加速度,作为反映非稳定杠铃卧推负荷任务运动表现和动作稳定性控制能力表现的指标。此外,采集运动过程中右侧肱二头肌、肱三头肌、三角肌前束、三角肌后束以及胸大肌的表面肌电信号。采用配对t检验对真、假刺激条件下的卧推次数差异性进行检验;采用重复测量设计的方差分析对三轴加速度、主动肌激活水平和拮抗肌共激活水平等指标的差异性进行检验。结果与结论:①真、假刺激干预后受试者卧推杠铃次数无显著差异,但经颅直流电刺激真刺激干预后Y轴的加速度平均幅值均显著小于经颅直流电刺激假刺激时;②经颅直流电刺激真刺激干预显著提升了三角肌前束的激活水平和三角肌后束的共激活水平;除三角肌后束外,各测试肌肉运动后半段的激活水平显著高于运动前半段;③经颅直流电刺激干预和运动阶段对各测试指标的影响无显著的交互作用;④提示经颅直流电刺激对非稳定杠铃卧推运动的肌肉耐力表现并无显著影响,但可以提高动作的稳定性,这可能与经颅直流电刺激可以显著提高三角肌前束激活水平和三角肌后束共激活水平,进而提高肩关节的刚度和稳定性有关;在竞技体育和临床康复训练中,可以根据训练目的考虑采用经颅直流电刺激调控非稳定负荷运动任务的表现。 展开更多
关键词 经颅直流电刺激 真刺激 假刺激 非稳定负荷运动任务 动作稳定性 表面肌电信号
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经颅直流电刺激联合耳针治疗老年抑郁症的临床效果观察及对病人认知功能、相关血清学指标的影响
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作者 刘丹 诸春明 +1 位作者 赵彦 毛静宇 《安徽医药》 2026年第2期372-376,共5页
目的探讨经颅直流电刺激疗法(tDCS)联合耳针治疗老年抑郁症(LLD)的临床效果,并观察其对病人认知功能、睡眠质量及血清学相关指标的影响。方法选取2023年1―10月在无锡市精神卫生中心就诊的LLD病人90例,按照随机数字表法分为tDCS联合耳... 目的探讨经颅直流电刺激疗法(tDCS)联合耳针治疗老年抑郁症(LLD)的临床效果,并观察其对病人认知功能、睡眠质量及血清学相关指标的影响。方法选取2023年1―10月在无锡市精神卫生中心就诊的LLD病人90例,按照随机数字表法分为tDCS联合耳针治疗组(tDCS+耳针组)、耳针治疗组(耳针组)及tDCS伪刺激组(伪刺激组),每组30例,分别于治疗前和治疗10周后采用汉密尔顿抑郁量表(HAMD)、蒙特利尔认知评估量表(MoCA)、匹兹堡睡眠指数(PSQI)评价三组LLD病人抑郁情绪、认知功能及睡眠情况,并观察治疗前后去甲肾上腺素(NE)、5-羟色胺(5-HT)、脑源性神经营养因子(BDNF)水平。结果治疗前三组病人的各项指标比较均差异无统计学意义(P>0.05),治疗10周后,三组间病人的抑郁情绪、认知功能及睡眠情况均较治疗前有改善(P<0.05),且相较于耳针组及伪刺激组,tDCS+耳针组对抑郁情绪[HAMD(28.00±7.66)分比(32.93±7.27)分、(33.70±8.45)分]、认知功能[MoCA(26.57±3.28)分比(24.87±3.95)分、(24.07±3.97)分]的改善更明显,对睡眠情况[PSQI(10.40±2.46)分比(11.13±2.87)分、(12.97±3.20)分]的改善也更明显(P<0.05);tDCS+耳针组与耳针组均能改善病人睡眠质量(P<0.05),但二者之间差异无统计学意义(P>0.05)。治疗后tDCS+耳针组5-HT[(119.54±12.23)μg/L比(102.11±10.24)μg/L]与BDNF[(20.14±5.27)μg/L比(13.37±5.14)μg/L]水平高于伪刺激组(P<0.05),NE水平差异无统计学意义(P>0.05)。结论tDCS联合耳针治疗对LLD病人的抑郁情绪、认知功能及睡眠情况均有改善作用,tDCS及耳针治疗作为一种非创伤性的物理治疗值得在临床应用中进行推广。 展开更多
关键词 抑郁症 认知功能障碍 经颅直流电刺激 耳针 脑源性神经营养因子 老年人
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中枢与外周康复技术影响脑卒中患者上肢功能和日常活动能力的网状Meta分析
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作者 陈金慧 于子夫 +3 位作者 高世爱 曹新燕 冷晓轩 刘西花 《中国组织工程研究》 北大核心 2026年第17期4457-4471,共15页
目的:上肢运动障碍是脑卒中患者最常见的并发症,患者功能障碍表现在外周肢体,而病变位于中枢大脑,然而目前仍缺乏不同中枢与外周干预方法单独或联合应用对脑卒中患者上肢运动功能及日常生活活动能力影响的Meta分析,给临床选择最佳康复... 目的:上肢运动障碍是脑卒中患者最常见的并发症,患者功能障碍表现在外周肢体,而病变位于中枢大脑,然而目前仍缺乏不同中枢与外周干预方法单独或联合应用对脑卒中患者上肢运动功能及日常生活活动能力影响的Meta分析,给临床选择最佳康复手段带来一定限制。采用网状Meta分析方法比较4种常用中枢康复方法(经颅磁刺激、经颅直流电刺激、镜像疗法与运动想象)与4种常用外周康复方法(康复机器人、肌电生物反馈、强制性运动疗法及功能性电刺激)单独或联合应用对脑卒中上肢运动功能及日常生活活动能力的影响,确定最佳康复方案。方法:计算机检索PubMed、Web of Science、Embase、The Cochrane Library、中国知网、万方、维普、中国生物医学文献服务系统,时限为数据库建库至2024-10-15,收集不同中枢或外周康复方法单独或联合应用对脑卒中患者上肢功能及日常生活活动能力的随机对照试验。使用Cochrane手册和修订版Jadad量表评价纳入文献偏倚风险和方法学质量,采用RevMan 5.4与Stata 18对Fugl-Meyer评定量表上肢部分评分、Wolf运动功能测试与改良Barthel指数进行网状Meta分析,使用GRADE证据等级系统评估结局指标的证据等级推荐强度。结果:①共纳入88篇研究,其中高质量82篇,低质量6篇,涉及5561例脑卒中患者,共形成19种康复方案;②Fugl-Meyer评定量表上肢部分评分累积排序概率图下面积排序前8种康复方案:经颅直流电刺激+机器人(99.4%)>运动想象疗法+机器人(84.4%)>运动想象疗法+强制性运动疗法(82.8%)>镜像疗法+肌电生物反馈疗法(81.2%)>运动想象疗法+肌电生物反馈疗法(77.0%)>重复经颅磁刺激+强制性运动疗法(69.9%)>经颅直流电刺激+肌电生物反馈疗法(67.1%)>重复经颅磁刺激+肌电生物反馈疗法(60.2%);③Wolf运动功能测试累积排序概率图下面积排序前3种康复方案:强制性运动疗法+经颅直流电刺激(70.7%)>强制性运动疗法(65.3%)>经颅直流电刺激(63.4%);④改良Barthel指数累积排序概率图下面积排序前8种康复方案:经颅直流电刺激+机器人(95.4%)>经颅直流电刺激+肌电生物反馈疗法(82.3%)>运动想象疗法+强制性运动疗法(79.7%)>重复经颅磁刺激+强制性运动疗法(79.5%)>功能性电刺激(74.2%)>运动想象疗法+肌电生物反馈疗法(68.6%)>镜像疗法+机器人(65.1%)>镜像疗法+肌电生物反馈疗法(51.0%)。结论:中等证据强度推荐经颅直流电刺激+机器人为促进脑卒中患者上肢运动功能及日常生活活动能力的最佳康复方案,中枢联合外周的康复方法对提高脑卒中患者上肢运动功能及日常生活活动能力的疗效优于单一康复手段,未来应开展更高质量及多中心的临床试验以验证该结果。 展开更多
关键词 脑卒中 上肢 运动功能 日常生活活动能力 经颅磁刺激 经颅直流电刺激 康复机器人 镜像疗法
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重复经颅磁刺激和经颅直流电刺激对脑瘫患儿运动功能及步态影响的网状Meta分析
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作者 曹新燕 于子夫 +3 位作者 冷晓轩 高世爱 陈金慧 刘西花 《中国组织工程研究》 北大核心 2026年第6期1539-1548,共10页
目的:研究表明,重复经颅磁刺激和经颅直流电刺激对改善脑瘫患儿粗大运动功能具有积极作用。采用网状Meta分析方法评价重复经颅磁刺激和经颅直流电刺激对脑瘫患儿下肢运动功能及步态改善的临床疗效。方法:检索中国知网、万方、维普、Sino... 目的:研究表明,重复经颅磁刺激和经颅直流电刺激对改善脑瘫患儿粗大运动功能具有积极作用。采用网状Meta分析方法评价重复经颅磁刺激和经颅直流电刺激对脑瘫患儿下肢运动功能及步态改善的临床疗效。方法:检索中国知网、万方、维普、SinoMed、PubMed、Web of Science、Medline数据库,搜索关于重复经颅磁刺激与经颅直流电刺激改善脑瘫患儿下肢运动功能及步态的随机对照试验,检索时限均为数据库建库至2024-10-05。筛选文献、提取资料并评价纳入研究的偏倚风险,采用Stata 15.0软件进行网状Meta分析,使用GRADE证据分级系统进行质量评价。结果:最终纳入19篇研究,涉及常规治疗、高频重复经颅磁刺激、低频重复经颅磁刺激、阳极经颅直流电刺激4种治疗方案。网状Meta分析结果显示,与常规治疗相比,低频重复经颅磁刺激改善脑瘫患儿粗大运动功能方面的疗效最佳[MD=9.48,95%CI(6.61,12.34),P<0.05],在缓解痉挛方面,高频重复经颅磁刺激的疗效最佳[MD=-0.63,95%CI(-1.72,0.45),P<0.05],经颅直流电刺激改善脑瘫患儿踝关节活动度和步速方面的疗效最佳[MD=2.27,95%CI(1.37,3.17),P<0.05;MD=0.11,95%CI(0.05,0.17),P<0.05]。结论:现有临床证据表明,对于脑瘫患儿,在改善下肢粗大运动功能方面,低频重复经颅磁刺激展现出最佳疗效;对于降低肌痉挛程度,高频重复经颅磁刺激的效果更为显著;在步态改善方面,经颅直流电刺激则表现出明显优势。 展开更多
关键词 无创脑刺激 脑瘫 下肢运动功能 步态 经颅磁刺激 经颅直流电刺激 运动功能康复 工程化组织构建
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不同神经调控刺激方式改善帕金森病患者非运动症状的网状Meta分析
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作者 冷晓轩 赵玉欣 刘西花 《中国组织工程研究》 北大核心 2026年第5期1282-1293,共12页
目的:已有研究证实,神经调控技术对帕金森病患者的临床症状有较为明显的改善作用,并且不同神经调控刺激方式之间存在疗效差异。采用网状Meta分析评价不同神经调控技术刺激方式改善帕金森病患者睡眠障碍及抑郁焦虑等非运动症状的疗效,探... 目的:已有研究证实,神经调控技术对帕金森病患者的临床症状有较为明显的改善作用,并且不同神经调控刺激方式之间存在疗效差异。采用网状Meta分析评价不同神经调控技术刺激方式改善帕金森病患者睡眠障碍及抑郁焦虑等非运动症状的疗效,探讨最佳神经调控刺激方案。方法:应用计算机检索中国生物医学文献数据库、万方数据库、维普数据库、中国知网及Web of Science、PubMed、The Cochrane Library、EMbase数据库中关于神经调控技术改善帕金森病患者睡眠障碍及抑郁焦虑的随机对照试验,对照组采用常规治疗(药物、常规康复治疗等)或假刺激,试验组在对照组的基础上加用神经调控技术。采用PEDro量表和Cochrane协作网推荐的偏倚风险评估工具对纳入的文献进行质量评价,采用RevMan 5.4和Stata 17.0对4个结局指标(睡眠障碍、焦虑症状、抑郁症状、生活质量)进行网状Meta分析。结果:①最终纳入29项随机对照试验,涉及6种神经调控刺激方式,包括经颅直流电刺激、高频重复经颅磁刺激、低频重复经颅磁刺激、丘脑底核脑深部电刺激、苍白球内侧脑深部电刺激、多靶点脑深部电刺激。②网状Meta分析结果显示:与常规治疗相比,经颅直流电刺激[SMD=-2.57,95%CI=(-4.52,-0.63),P<0.05]在改善帕金森病患者睡眠障碍方面的疗效最佳;在改善帕金森病患者抑郁症状方面,苍白球内侧脑深部电刺激[SMD=-1.00,95%CI=(-1.87,-0.14),P<0.05]的疗效最佳,其次为低频重复经颅磁刺激[SMD=-0.91,95%CI=(-1.60,-0.23),P<0.05]、丘脑底核脑深部电刺激[SMD=-0.82,95%CI=(-1.56,-0.08),P<0.05]、高频重复经颅磁刺激[SMD=-0.75,95%CI=(-0.97,-0.53),P<0.05];在改善帕金森病患者焦虑症状方面,高频重复经颅磁刺激[SMD=-0.86,95%CI=(-1.54,-0.18),P<0.05]的疗效最佳;在改善患者生活质量方面,苍白球内侧脑深部电刺激[SMD=-0.79,95%CI=(-1.55,-0.04),P<0.05]的疗效最佳,其次为高频重复经颅磁刺激[SMD=-0.63,95%CI=(-0.90,-0.36),P<0.05]、经颅直流电刺激[SMD=-0.50,95%CI=(-0.80,-0.19),P<0.05]。结论:神经调控技术在改善帕金森病患者非运动症状方面具有显著疗效,其中,经颅直流电刺激改善睡眠障碍的疗效最佳,苍白球内侧脑深部电刺激改善抑郁症状的疗效最佳,高频重复经颅磁刺激改善焦虑症状的疗效最佳,苍白球内侧脑深部电刺激改善生活质量的疗效最佳。 展开更多
关键词 帕金森病 神经调控技术 经颅直流电 重复经颅磁刺激 脑深部电刺激 睡眠障碍 抑郁 焦虑 生活质量 网状Meta分析 工程化组织构建
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直流风洞尖劈对小缩尺比风场模拟影响研究
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作者 臧振浩 倪梁瑞 李明 《山西建筑》 2026年第1期1-5,共5页
为方便调试出符合试验要求的小几何缩尺比边界层风场,以直流风洞中1∶3 000的B类风场调试过程为例,探讨了在直流风洞中尖劈挡风板尺寸、形状和尖劈的间距对边界层风场模拟的影响,结果表明:改变尖劈迎风板底边宽度对风场湍流度整体分布... 为方便调试出符合试验要求的小几何缩尺比边界层风场,以直流风洞中1∶3 000的B类风场调试过程为例,探讨了在直流风洞中尖劈挡风板尺寸、形状和尖劈的间距对边界层风场模拟的影响,结果表明:改变尖劈迎风板底边宽度对风场湍流度整体分布影响较大,同时也会影响风剖面分布;改变迎风板形状可在保持风速剖面特性的情况下改变整体湍流度分布;适当缩小尖劈的间距能显著提高流场湍流度大小且对风剖面影响较小。最后开展了D类风场小缩尺比模拟风洞试验,采用文中提出的尖劈设计方法进行了风场模拟,并与规范要求的目标风场进行对比,验证了该方法的有效性和精度。 展开更多
关键词 小缩尺比 风场模拟 尖劈 直流风洞
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基于改进基频调制电流源换流器的HVDC故障电流抑制策略
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作者 冯定腾 熊小玲 +3 位作者 姚辰昊 周子涵 王胜威 赵成勇 《电力系统自动化》 北大核心 2026年第1期157-167,共11页
改进基频调制电流源换流器(EFFM-CSC)作为基于全控型集成门极换流晶闸管(IGCT)器件的电流源换流器,具有拓扑结构简单、体积重量小、谐波特性好和有功/无功功率灵活可调的优点,受到了广泛关注。然而,基于EFFM-CSC的高压直流(HVDC)系统同... 改进基频调制电流源换流器(EFFM-CSC)作为基于全控型集成门极换流晶闸管(IGCT)器件的电流源换流器,具有拓扑结构简单、体积重量小、谐波特性好和有功/无功功率灵活可调的优点,受到了广泛关注。然而,基于EFFM-CSC的高压直流(HVDC)系统同样面临直流线路短路这一严重故障,目前尚缺乏系统性的定量分析和研究。因此,针对EFFM-CSC换流站拓扑以及短路瞬间开关状态,建立了复频域下的运算电路模型。然后,根据储能等效原则得到等效RLC参数,构建直流短路时EFFM-CSC的故障等值模型,推导出直流故障电流解析计算公式,并讨论了系统参数和故障时刻对故障电流的影响。根据EFFM-CSC直流短路故障特性,提出了一种故障识别判据和故障电流抑制策略,并对抑制策略的控制参数进行整定。最后,基于仿真分析验证了所提故障电流计算方法和故障抑制策略的正确性。 展开更多
关键词 电流源换流器 改进基频调制 高压直流 短路 故障识别 故障电流抑制
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经颅直流电刺激即刻和3周后上肢运动功能及脑功能分析
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作者 侯兵 赵鸿斐 +5 位作者 车鹏程 王梓祎 高赞 陈琳渝 王金芝 窦娜 《中国组织工程研究》 北大核心 2026年第12期3066-3074,共9页
背景:脑卒中后由于脑神经功能缺损会进一步导致患者上肢运动功能障碍,而脑功能和上肢运动功能恢复对改善日常生活活动能力具有重要作用。尽管已有研究探讨了单次经颅直流电刺激即刻对脑卒中患者脑电活动的影响,但针对短期疗程经颅直流... 背景:脑卒中后由于脑神经功能缺损会进一步导致患者上肢运动功能障碍,而脑功能和上肢运动功能恢复对改善日常生活活动能力具有重要作用。尽管已有研究探讨了单次经颅直流电刺激即刻对脑卒中患者脑电活动的影响,但针对短期疗程经颅直流电刺激的治疗效果仍需进一步深入探究。目的:评估脑卒中患者经颅直流电刺激即刻和3周后的上肢运动功能及脑功能。方法:招募30例缺血性脑卒中偏瘫患者,随机分为试验组(n=15)和对照组(n=15)。试验组在常规康复治疗基础上接受双极经颅直流电刺激,而对照组接受伪经颅直流电刺激,治疗周期为3周。在干预前、首次干预后和干预3周后进行Fugl-Meyer评定量表上肢部分评分、Wolf运动功能测试评分及静息态脑电图评估。结果与结论:(1)对照组干预后即刻与干预前相比无显著变化,而试验组干预后即刻Fugl-Meyer评定量表上肢部分评分较干预前提高(P <0.05);(2)与干预前相比,两组患者干预3周后Fugl-Meyer评定量表上肢部分评分、Wolf运动功能测试评分提高及脑电频带变化明显改善(P <0.05),试验组改善的效果更明显;(3)相关性分析显示,试验组干预前后Fugl-Meyer评定量表上肢部分评分差值及Wolf运动功能测试评分差值与δ全脑平均功率呈负相关关系(r=-0.716,r=-0.546),与α全脑平均功率呈正相关关系(r=0.520,r=0.669)。结果表明,在常规康复治疗基础上增加双极经颅直流电刺激可以有效改善缺血性脑卒中患者的脑功能及上肢运动功能。上肢运动功能改善与脑功能恢复趋向正常化相关。 展开更多
关键词 经颅直流电刺激 脑卒中 双侧刺激 康复训练 上肢运动功能 脑功能 脑电活动 神经康复
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高压直流输电接地极对埋地管道干扰及防护研究进展
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作者 高杰 田海州 +4 位作者 黎少飞 刘天慧 郭小东 安兵 陆涛 《材料保护》 2026年第1期15-25,共11页
随着我国直流高压输电工程的日渐增多,高压直流输电(HVDC)系统的接地极对埋地金属管道的干扰问题日益凸显。为对干扰问题进行准确的研究分析和防护评估,对近年来HVDC系统干扰的研究方法和影响因素进行了调研,从实地现场试验、室内模拟... 随着我国直流高压输电工程的日渐增多,高压直流输电(HVDC)系统的接地极对埋地金属管道的干扰问题日益凸显。为对干扰问题进行准确的研究分析和防护评估,对近年来HVDC系统干扰的研究方法和影响因素进行了调研,从实地现场试验、室内模拟实验、数值模拟技术和影响因素4个方面分析了管道所受干扰与腐蚀规律,同时对我国目前常用的HVDC系统的杂散电流防护技术进行了总结,并阐述了其优缺点和适用范围。最后,对杂散电流干扰及防护的研究方向进行了展望。 展开更多
关键词 高压直流 埋地管道 研究方法 模拟实验 防护
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分期针刺联合双侧经颅直流电交替刺激治疗脑卒中后口咽期吞咽障碍的临床观察
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作者 王肃馨 王立峰 +1 位作者 张丽丽 董红娟 《广州中医药大学学报》 2026年第1期103-109,共7页
【目的】观察分期针刺联合双侧经颅直流电交替刺激治疗脑卒中后口咽期吞咽障碍的临床疗效。【方法】选取2023年6月至2024年6月于陕西省康复医院神经康复病区收治的60例明确诊断为脑卒中后口咽期吞咽障碍的患者为研究对象。按照随机数字... 【目的】观察分期针刺联合双侧经颅直流电交替刺激治疗脑卒中后口咽期吞咽障碍的临床疗效。【方法】选取2023年6月至2024年6月于陕西省康复医院神经康复病区收治的60例明确诊断为脑卒中后口咽期吞咽障碍的患者为研究对象。按照随机数字表将患者随机分为观察组和对照组,每组各30例。2组患者均给予常规吞咽功能训练。对照组给予双侧经颅直流电交替刺激治疗,观察组在对照组治疗的基础上,给予分期针刺治疗。共治疗4周。治疗1个月后,评价2组临床疗效。观察2组患者治疗前后洼田饮水试验分级评分(WST)和电视透视吞咽功能评分(VFSS)的变化情况,以及功能性经口摄食量表评分(FOIS)和吞咽障碍生活质量评分(SWAL-QOL)的情况。比较2组患者治疗前后表面肌电图(sEMG)舌骨肌群波幅及吞咽时间的变化情况。并评价2组的安全性及并发症的发生情况。【结果】(1)治疗后,2组患者WST、VFSS评分均明显改善(P<0.05),且观察组在改善WST、VFSS评分方面明显优于对照组,差异有统计学意义(P<0.05)。(2)治疗后,2组患者FOIS、SWAL-QOL评分均明显改善(P<0.05),且观察组在改善FOIS、SWAL-QOL评分方面明显优于对照组,差异有统计学意义(P<0.05)。(3)治疗后,2组患者的sEMG波幅及吞咽时间均明显改善(P<0.05),且观察组在改善sEMG波幅及吞咽时间方面明显优于对照组,差异有统计学意义(P<0.05)。(4)观察组并发症发生率为16.67%(5/30),对照组为30.00%(9/30)。观察组并发症发生率明显低于对照组,差异有统计学意义(P<0.05)。(5)观察组总有效率为93.34%(28/30),对照组为76.67%(23/30)。观察组疗效优于对照组,差异有统计学意义(P<0.05)。【结论】分期针刺联合双侧经颅直流电交替刺激治疗脑卒中后口咽期吞咽障碍患者,能显著改善患者的吞咽功能,从而提高患者的生活质量,降低并发症的发生率,疗效显著。 展开更多
关键词 分期针刺 经颅直流电刺激 脑卒中 吞咽障碍 口咽期 临床观察
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新一代高韧性直流输电技术(二):高倍载模块化换向式换流器 被引量:2
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作者 赵彪 白睿航 +7 位作者 张雪垠 崔彬 屈鲁 吴锦鹏 宋强 余占清 魏晓光 曾嵘 《中国电机工程学报》 北大核心 2025年第2期665-678,I0022,共15页
针对高韧性直流输电技术对高倍载、高经济性直流换流器的需求,提出一种高倍载模块化换向式换流器(high-overload modular commutated converter,MCC)。首先,对MCC的拓扑构造和运行原理进行详细分析,指出其器件软开关特性、桥臂能量脉动... 针对高韧性直流输电技术对高倍载、高经济性直流换流器的需求,提出一种高倍载模块化换向式换流器(high-overload modular commutated converter,MCC)。首先,对MCC的拓扑构造和运行原理进行详细分析,指出其器件软开关特性、桥臂能量脉动优化和高倍载潜力;针对MCC的宽范围电压变比调节、串联模块电压均衡控制、架空线应用中的直流故障自清除等关键问题,给出解决方案;以±500 kV/2000 MW直流输电系统为例,分析MCC的元件用量、体积、效率、成本等技术特性,并与常规模块化多电平IGBT换流器进行综合对比;最后,研制基于IGCT-Plus器件的±15 kV/60 MVA MCC产品,开展综合性测试验证。结果表明,提出的MCC有望将现有换流器技术方案的体积、成本、损耗率分别减小达50%,在电能变换与传输中具有广阔的应用前景。 展开更多
关键词 直流输电 直流换流器 交直流功率变换 集成门极换流晶闸管
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