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“Flow” Transcranial Direct Current Stimulation (tDCS) for Depression Treatment in a Primary Healthcare General Practice—An Open-Label Cohort Study Measuring Montgomery-Åsberg Depression Rating Scale (MADRS-S) Outcomes
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作者 Chris Griffiths Harmony Jiang +1 位作者 David Smart Azhar Zafar 《Open Journal of Psychiatry》 2024年第4期386-399,共14页
Background: Flow FL-100 is a transcranial direct current stimulation (tDCS) device self-administered by a patient at home in combination with a software application delivered wellbeing behaviour therapy training. tDCS... Background: Flow FL-100 is a transcranial direct current stimulation (tDCS) device self-administered by a patient at home in combination with a software application delivered wellbeing behaviour therapy training. tDCS has evidence of effectiveness in treating symptoms of depression. Purpose/Aim: This post marketing study evaluated the effect of Flow on depression for primary care general practice patients with depression symptoms. Methods: Open-label patient cohort design with no control group. Inclusion criteria were aged 18 years or over and reporting depression symptoms. Participants self-administered five 30 minute tDCS sessions per week for the first three weeks, and then 3 sessions per week following this. Three, six and ten week assessment with participant self-report measure: Montgomery- Åsberg Depression Rating Scale (MADRS-S). Results: MADRS-S remission rates were between 29% - 30% at three weeks, 33% - 34% at six-weeks and 50% at 10-weeks treatment. There was a significant improvement in MADRS-S with large effect sizes at all time points. Conclusions: Flow tDCS can be delivered through a primary healthcare general practice service and patients will choose to use. Flow tDCS provides an effective depression treatment in addition and as an alternative to antidepressants and psychotherapy. tDCS has evidence as an effective depression treatment, and the widespread availability of tDCS in primary care general practice should be considered. 展开更多
关键词 DEPRESSION Transcranial direct current Stimulation Wellbeing General Practice
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Transcranial direct current stimulation efficacy in trigeminal neuralgia
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作者 Theodoros Fasilis Stylianos Gatzonis +2 位作者 Panayiotis Patrikelis Stefanos Korfias Athanasia Alexoudi 《World Journal of Clinical Cases》 SCIE 2024年第5期1036-1038,共3页
Trigeminal neuralgia is a severe,disabling pain and its deafferentation remains a challenge for health providers.Transcranial direct current stimulation is a non-invasive stimulation technique which finds new utility ... Trigeminal neuralgia is a severe,disabling pain and its deafferentation remains a challenge for health providers.Transcranial direct current stimulation is a non-invasive stimulation technique which finds new utility in managing pain.There-fore,the introduction of alternative,non-invasive,safe,and effective methods should be considered in treating patients with trigeminal neuralgia unresponsive to conventional treatment. 展开更多
关键词 Trigeminal neuralgia Patient-controlled intravenous analgesia NEUROMODULATION Transcranial direct current stimulation
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The Effects of the Geometry of a Current Collector with an Equal Open Ratio on Output Power of a Direct Methanol Fuel Cell
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作者 Yingli Zhu Jiachi Xie +2 位作者 Mingwei Zhu Jun Zhang Miaomiao Li 《Energy Engineering》 EI 2024年第5期1161-1172,共12页
The open ratio of a current collector has a great impact on direct methanol fuel cell(DMFC)performance.Although a number of studies have investigated the influence of the open ratio of DMFC current collectors,far too ... The open ratio of a current collector has a great impact on direct methanol fuel cell(DMFC)performance.Although a number of studies have investigated the influence of the open ratio of DMFC current collectors,far too little attention has been given to how geometry(including the shape and feature size of the flow field)affects a current collector with an equal open ratio.In this paper,perforated and parallel current collectors with an equal open ratio of 50%and different feature sizes are designed,and the corresponding experimental results are shown to explain the geometry effects on the output power of the DMFC.The results indicate that the optimal feature sizes are between 2 and 2.5 mm for both perforated and parallel flow field in the current collectors with an equal open ratio of 50%.This means that for passive methanol fuel cells,to achieve the highest output power,the optimal feature size of the flow field in both anode and cathode current collectors is between 2 and 2.5 mm under the operating mode of this experiment.The effects of rib and channel position are also investigated,and the results indicate that the optimum pattern depends on the feature sizes of the flow field. 展开更多
关键词 direct methanol fuel cell GEOMETRY open ratio current collector POSITION
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Research and exploration of direct current power supply and distribution systems for Antarctic research stations
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作者 WANG Lei 《Advances in Polar Science》 CSCD 2024年第2期228-237,共10页
The power supply and distribution systems for Antarctic research stations have special characteristics.In light of a worldwide trend toward a gradual increase in the application of renewable energy,an analysis was per... The power supply and distribution systems for Antarctic research stations have special characteristics.In light of a worldwide trend toward a gradual increase in the application of renewable energy,an analysis was performed to assess the feasibility of achieving a direct current power supply and distribution at Antarctic research stations by comparing the characteristics of direct current and alternating current electricity.Research was also performed on the status quo and future trends in direct current power supply and distribution systems in Antarctica research stations in combination with case studies. 展开更多
关键词 direct current alternating current renewable energy ANTARCTIC research station
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Fluid-chemical modeling of the near-cathode sheath formation process in a high current broken in DC air circuit breaker
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作者 彭世东 李静 +3 位作者 段薇 曹云东 刘树鑫 黄浩 《Chinese Physics B》 SCIE EI CAS CSCD 2024年第1期523-538,共16页
When the contacts of a medium-voltage DC air circuit breaker(DCCB) are separated, the energy distribution of the arc is determined by the formation process of the near-electrode sheath. Therefore, the voltage drop thr... When the contacts of a medium-voltage DC air circuit breaker(DCCB) are separated, the energy distribution of the arc is determined by the formation process of the near-electrode sheath. Therefore, the voltage drop through the near-electrode sheath is an important means to build up the arc voltage, which directly determines the current-limiting performance of the DCCB. A numerical model to describe the near-electrode sheath formation process can provide insight into the physical mechanism of the arc formation, and thus provide a method for arc energy regulation. In this work, we establish a two-dimensional axisymmetric time-varying model of a medium-voltage DCCB arc when interrupted by high current based on a fluid-chemical model involving 16 kinds of species and 46 collision reactions. The transient distributions of electron number density, positive and negative ion number density, net space charge density, axial electric field, axial potential between electrodes, and near-cathode sheath are obtained from the numerical model. The computational results show that the electron density in the arc column increases, then decreases, and then stabilizes during the near-cathode sheath formation process, and the arc column's diameter gradually becomes wider. The 11.14 V–12.33 V drops along the17 μm space charge layer away from the cathode(65.5 k V/m–72.5 k V/m) when the current varies from 20 k A–80 k A.The homogeneous external magnetic field has little effect on the distribution of particles in the near-cathode sheath core,but the electron number density at the near-cathode sheath periphery can increase as the magnetic field increases and the homogeneous external magnetic field will lead to arc diffusion. The validity of the numerical model can be proven by comparison with the experiment. 展开更多
关键词 near-cathode sheath atmospheric pressure air arc fluid-chemical model high current dc air circuit breaker(dcCB)
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Effect of transcranial direct current stimulation on supernumerary phantom limb pain in spinal cord injured patient:A case report
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作者 Hyo-Sik Park Jae-Hyung Kim 《World Journal of Clinical Cases》 SCIE 2024年第17期3177-3182,共6页
BACKGROUND Supernumerary phantom limb(SPL)sensation is the experience of additional limbs,either single or a pair of limbs.Unique to traumatic spinal cord injuries,we report effect of transcranial direct current stimu... BACKGROUND Supernumerary phantom limb(SPL)sensation is the experience of additional limbs,either single or a pair of limbs.Unique to traumatic spinal cord injuries,we report effect of transcranial direct current stimulation(tDCS)on SPL pain in a patient with cervical cord injury.CASE SUMMARY The subject was a 57-year-old man who was diagnosed with complete spinal cord injury(C6/C5,motor level;C5/C5,sensory level;AIS-A)approximately three months ago.After a period of 2 wk,we administered anodal tDCS over the motor cortex for 15 minutes at an intensity of 1.5 mA.Following that treatment,the patient experienced a decrease of SPL pain intensity and frequency,which lasted for 1 week after the end of treatment.CONCLUSION Targeting the motor cortex through neuromodulation appears to be a promising option for the management of SPL pain. 展开更多
关键词 Supernumerary phantom limb pain Spinal cord injury transcranial direct current Stimulation NEUROMODULATION Case report
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Transcranial Direct Current Stimulation: Effects on Motor and Non-Motor Symptoms of Parkinson’s Disease
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作者 Fayda Protásio Carlos Alberto Bezerra Tomaz +3 位作者 Joaquim Brasil-Neto Pedro Brandão Nasser Allam Maria Clotilde Henriques Tavares 《Journal of Behavioral and Brain Science》 2024年第5期135-160,共26页
Introduction: In the last thirty years, brain neuromodulation techniques have been used as an alternative to pharmacological treatment of neurological disorders. Parkinson’s disease (PD) is a neurodegenerative disord... Introduction: In the last thirty years, brain neuromodulation techniques have been used as an alternative to pharmacological treatment of neurological disorders. Parkinson’s disease (PD) is a neurodegenerative disorder leading to bradykinesia, rest tremor, postural changes, and non-motor symptoms such as depression, anxiety, sleep disorders, pain, and cognitive decline that compromises executive functions (EFs), responsible for the orderly execution of behaviors and tasks of daily life and intentional and directed actions. To this date, a few studies with transcranial direct current stimulation (tDCS) have shown beneficial effects in PD patients concerning specific motor and non-motor symptoms, targeting the motor cortex and/or prefrontal regions. Objective: The main objective of this study was to evaluate the effects of left prefrontal tDCS across a broad spectrum of motor and non-motor symptoms of PD using established validated scales. Method: Single-blind randomized clinical trial with 18 volunteers with PD, aged between 45 and 80 years (66.1 ± 9.65), who met inclusion and exclusion criteria. Participants were submitted to assessments of motor and non-motor functions employing psychometric scales and tests to evaluate EFs and were randomly divided into two groups: control (sham stimulation) and experimental (active stimulation). All participants were involved in three separate tDCS sessions. The anode was positioned over the left dorsolateral prefrontal cortex and the cathode over the right supraorbital region, with a direct current intensity of 2 mA, lasting 20 minutes. At the end of the three sessions, all participants were reassessed. Results: Significant effects of tDCS on non-motor functions were observed for cognition (verbal fluency of actions, clock copy test, appointment by visual confrontation, and verbal memory with immediate free recall) and subjective assessment of sleep quality (overall restlessness and discomfort in the arms and legs at night, leg and arm cramps at night and distressing dreams). There was also an improvement in the rate of errors and successes for congruent and incongruent stimuli of the Stroop Test. The beneficial effects on motor function were decreased rigidity, improved gait, and greater agility in the finger-tapping test. Conclusion: Three tDCS sessions showed positive results for participants with PD, producing significant improvements in various motor and non-motor functions, including sleep quality, cognition, and EFs. Additionally, the present results indicate that tDCS neuromodulation of the left dorsolateral prefrontal cortex region is feasible, safe, and provides significant objective benefits for PD patients. 展开更多
关键词 Parkinson’s Disease NEUROMODULATION Transcranial direct current Stimulation—tdcS Movement Disorders MOOD SLEEP COGNITION
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Positive Effect of Transcranial Direct Current Stimulation on Visual Verbal Working Memory in Patients with Attention-Deficit/Hyperactivity Disorder
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作者 Tomoko Uchida Daisuke Matsuzawa +7 位作者 Tadashi Shiohama Katsunori Fujii Akihiro Shiina Masamitsu Naka Katsuo Sugita Eiji Shimizu Naoki Shimojo Hiromichi Hamada 《Open Journal of Psychiatry》 2024年第4期334-346,共13页
Background: Working memory is an executive function that plays an important role in many aspects of daily life, and its impairment in patients with attention-deficit/hyperactivity disorder (ADHD) affects quality of li... Background: Working memory is an executive function that plays an important role in many aspects of daily life, and its impairment in patients with attention-deficit/hyperactivity disorder (ADHD) affects quality of life. The dorsolateral prefrontal cortex (DLPFC) has been a good target site for transcranial direct current stimulation (tDCS) due to its intense involvement in working memory. In our 2018 study, tDCS improved visual-verbal working memory in healthy subjects. Objective: This study examines the effects of tDCS on ADHD patients, particularly on verbal working memory. Methods: We conducted an experiment involving verbal working memory of two modalities, visual and auditory, and a sustained attention task that could affect working memory in 9 ADHD patients. Active or sham tDCS was applied to the left DLPFC in a single-blind crossover design. Results: tDCS significantly improved the accuracy of visual-verbal working memory. In contrast, tDCS did not affect auditory-verbal working memory and sustained attention. Conclusion: tDCS to the left DLPFC improved visual-verbal working memory in ADHD patients, with important implications for potential ADHD treatments. 展开更多
关键词 Working Memory Attention-Deficit/Hyperactivity Disorder Dorsolateral Prefrontal Cortex Transcranial direct current Stimulation
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Transcranial direct current stimulation as early augmentation in adolescent obsessive compulsive disorder:A pilot proof-of-concept randomized control trial
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作者 Aditya Agrawal Vivek Agarwal +1 位作者 Sujita Kumar Kar Amit Arya 《World Journal of Clinical Pediatrics》 2024年第2期161-170,共10页
BACKGROUND Transcranial direct current stimulation(tDCS)is proven to be safe in treating various neurological conditions in children and adolescents.It is also an effective method in the treatment of OCD in adults.AIM... BACKGROUND Transcranial direct current stimulation(tDCS)is proven to be safe in treating various neurological conditions in children and adolescents.It is also an effective method in the treatment of OCD in adults.AIM To assess the safety and efficacy of tDCS as an add-on therapy in drug-naive adolescents with OCD.METHODS We studied drug-naïve adolescents with OCD,using a Children’s Yale-Brown obsessive-compulsive scale(CY-BOCS)scale to assess their condition.Both active and sham groups were given fluoxetine,and we applied cathode and anode over the supplementary motor area and deltoid for 20 min in 10 sessions.Reassessment occurred at 2,6,and 12 wk using CY-BOCS.RESULTS Eighteen adolescents completed the study(10-active,8-sham group).CY-BOCS scores from baseline to 12 wk reduced significantly in both groups but change at baseline to 2 wk was significant in the active group only.The mean change at 2 wk was more in the active group(11.8±7.77 vs 5.25±2.22,P=0.056).Adverse effects between the groups were comparable.CONCLUSION tDCS is safe and well tolerated for the treatment of OCD in adolescents.However,there is a need for further studies with a larger sample population to confirm the effectiveness of tDCS as early augmentation in OCD in this population. 展开更多
关键词 Adolescents Early augmentation Obsessive compulsive disorder SAFETY Transcranial direct current stimulation
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Effects of transcranial direct current stimulation (tDCS) for auditory hallucinations: A systematic review 被引量:1
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作者 Haibin LI Yiran WANG +2 位作者 Jiangling JIANG Wei LI Chunbo LI 《上海精神医学》 CSCD 2016年第6期301-308,共8页
关键词 TdcS 电刺激 系统 直流 随机对照试验 中文科技期刊数据库 医学文献数据库 精神分裂症
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Clay Minerals Channels Identification in the Tindikala-Boutou Area (Eastern-Cameroon) along the Kadey River Using Direct Current (DC) Method
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作者 Daniel Hervé Gouet Arsène Meying +1 位作者 Stéphane Patrick Assembe Théophile Ndougsa-Mbarga 《Journal of Geoscience and Environment Protection》 2015年第6期123-133,共11页
To achieve the current study, geoelectrical surveys along six (06) profiles of 4 km long in a 100 m × 200 m grid defined according to the triangulation principle in the Tindikala-Boutou (Eastern-Cameroon) area al... To achieve the current study, geoelectrical surveys along six (06) profiles of 4 km long in a 100 m × 200 m grid defined according to the triangulation principle in the Tindikala-Boutou (Eastern-Cameroon) area along the Kadey River have been made through electrical sounding and profiling following Schlumberger array. The instrument is the resistive meter Syscal Junior 48 (IRIS Instrument). The data have been processed and modelled with Res2Dinv and Winsev softwares, and then interpolated with Surfer software. Investigation method used is the Direct Current (DC) method. Interpretations and analyses of results from the investigation method highlight weak zones or conductive discontinuities. The latter has been identified as shear zones within granitic structures of the Precambrian basement, according to the geologic and tectonic background of the area. The structural trend of these shear zones is E-W approximately. The mineralization characterized by conductive zones proves the presence of clay minerals disseminated in weathered quartz vein, which cross the shear zones. The intense activities of gold washers encountered in the studied area are able to attest the presence of clay minerals concentrations. 展开更多
关键词 Geoelectrical Surveys direct current METHOD RESISTIVITY Shear ZONES Clay MINERALS
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Clinical Trial Demonstrates Efficacy of Transcranial Direct Current Stimulation (tDCS) in Improving Pain Management from Post-Laminectomy Syndrome
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作者 Marilia Capuço Oliveira Fernanda Menezes de Faria +3 位作者 Gerardo Maria de Araújo Filho Ana Carolina Gonçalves Olmos Demosthenes Santana Silva Junior Camila Souza Alves Cosmo 《Pain Studies and Treatment》 2023年第4期27-42,共16页
Chronic pain, a multidimensional experience affecting individuals’ sensory, cognitive, and emotional aspects, significantly impacts their quality of life. Post-laminectomy syndrome, a condition characterized by persi... Chronic pain, a multidimensional experience affecting individuals’ sensory, cognitive, and emotional aspects, significantly impacts their quality of life. Post-laminectomy syndrome, a condition characterized by persistent back pain following spinal surgery, often leads to disability and increased healthcare utilization. Methods: This randomized, controlled, blind clinical trial aimed to investigate the efficacy of Transcranial Direct Current Stimulation (tDCS) in managing pain from post-laminectomy syndrome in patients. Twenty-four participants were assigned to three groups: sham stimulation, active stimulation over primary motor cortex (M1), or stimulation over dorsolateral prefrontal cortex (DLPFC). Stimulation was administered for five consecutive days, 20 minutes per session, using a current of 1.5 mA through 25 cm<sup>2</sup> electrodes. Pain intensity was assessed using Visual Analog Scale (VAS) before, during, and after intervention. Results: An ANOVA model demonstrates significant reduction in pain intensity compared to baseline in VAS, (F(7, 285) = 12.292;p 0.001;Power = 1.000;η2p = 0.534), in tDCS applied to M1, after five days of intervention. After stimulation, a significant improvement was observed in WHOQoL-Bref Quality of life item 1 (p = 0.04), considering statistical significant difference p 0.05. Correlation between the variables: quality of life, depression, anxiety and pain also demonstrates reduction in depression and anxiety according to Beck’s Depression and Anxiety Inventories (BDI and BAI), p 0.05. This effect was not observed in DLPFC stimulation group. Patients who believed they received active stimulation, in sham group, demonstrated potential for effective blinding. Conclusion: The tDCS applied to primary motor cortex effectively improved pain management and psychiatry symptoms in post-laminectomy syndrome patients. The technique’s low cost, ease of use, and high tolerability make it a promising adjuvant therapy for chronic pain conditions like post-laminectomy syndrome. 展开更多
关键词 Non-Invasive Neuromodulation Transcranial direct current Stimulation Post-Laminectomy Syndrome Chronic Pain
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Highly Effective Brushless DC Motor in Which Unidirectional Current Flows in
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作者 Y. Komatsu T.A. Amarsanaa Y. Araki S.A.K. Zawawi 《Journal of Energy and Power Engineering》 2010年第10期58-64,共7页
Authors developed a highly effective brushless DC motor with a simple operation principle. If the operation principle of the motor is simple, a drive circuit will also become simple and its production cost will be low... Authors developed a highly effective brushless DC motor with a simple operation principle. If the operation principle of the motor is simple, a drive circuit will also become simple and its production cost will be lower. From the above fact, Minato motor was noticed. In this motor, a unidirectional current flows in the electromagnets. In other words, unidirectional windings are used. In this motor, only strong repulsive force is utilized when a permanent magnet of a rotor and an electromagnet of a stator are adjacent. Hence, torque constant becomes higher and the efficiency of the motor is high. However, an effective value of the electromagnetic current increases because a large current flows in a short period. Therefore, copper loss increases and the efficiency of the motor decreases. In order to solve above defects, a new motor is proposed. From the experiment, it is clarified that the efficiency of the proposed motor is higher than that of the commercial motors. 展开更多
关键词 Brushless dc motor Minato motor repulsive force unidirectional current back-EMF.
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Effects of direct current electric field on corrosion behaviour of copper, Cl- ion migration behaviour and dendrites growth under thin electrolyte layer 被引量:11
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作者 黄华良 潘志权 +1 位作者 郭兴蓬 邱于兵 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第1期285-291,共7页
Effect of direct current electric field (DCEF) on corrosion behaviour of copper printed circuit board (PCB-Cu), Cl-ion migration behaviour, dendrites growth under thin electrolyte layer was investigated using pote... Effect of direct current electric field (DCEF) on corrosion behaviour of copper printed circuit board (PCB-Cu), Cl-ion migration behaviour, dendrites growth under thin electrolyte layer was investigated using potentiodynamic polarization and scanning electron microscopy (SEM) with energy dispersive spectrometer (EDS). Results indicate that DCEF decreases the corrosion of PCB-Cu;Cl-ions directionally migrate from the negative pole to the positive pole, and enrich on the surface of the positive pole, which causes serious localized corrosion; dendrites grow on the surface of the negative pole, and the rate and scale of dendrite growth become faster and greater with the increase of external voltage and exposure time, respectively. 展开更多
关键词 COPPER DENDRITES MIGRATION direct current electric field thin electrolyte layer copper printed circuit board
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Grain refinement of pure aluminum by direct current pulsed magnetic field and inoculation 被引量:5
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作者 陈航 接金川 +2 位作者 付莹 马红军 李廷举 《Transactions of Nonferrous Metals Society of China》 SCIE EI CAS CSCD 2014年第5期1295-1300,共6页
The combined effects of direct current pulsed magnetic field (DC-PMF) and inoculation on pure aluminum were investigated, the grain refinement behavior of DC-PMF and inoculation was discussed. The experimental resul... The combined effects of direct current pulsed magnetic field (DC-PMF) and inoculation on pure aluminum were investigated, the grain refinement behavior of DC-PMF and inoculation was discussed. The experimental results indicate that the solidification micro structure of pure aluminum can be greatly refined under DC-PMF. Refinement of pure aluminum is attributed to electromagnetic undercooling and forced convection caused by DC-PMF. With single DC-PMF, the grain size in the equiaxed zone is uneven. However, under DC-PMF, by adding 0.05% (mass fraction) Al5Ti-B, the grain size of the sample is smaller, and the size distribution is more uniform than that of single DC-PMF. Furthermore, under the combination of DC-PMF and inoculation, with the increase of output current, the grain size is further reduced. When the output current increases to 100 A, the average grain size can decrease to 113 μn. 展开更多
关键词 direct current pulsed magnetic field pure aluminum inoculation grain refinement solidification micro structure
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Finite element numerical simulation of 2.5D direct current method based on mesh refinement and recoarsement 被引量:3
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作者 张钱江 戴世坤 +3 位作者 陈龙伟 强建科 李昆 赵东东 《Applied Geophysics》 SCIE CSCD 2016年第2期257-266,416,417,共12页
To deal with the problem of low computational precision at the nodes near the source and satisfy the requirements for computational efficiency in inversion imaging and finite-element numerical simulations of the direc... To deal with the problem of low computational precision at the nodes near the source and satisfy the requirements for computational efficiency in inversion imaging and finite-element numerical simulations of the direct current method, we propose a new mesh refinement and recoarsement method for a two-dimensional point source. We introduce the mesh refinement and mesh recoarsement into the traditional structured mesh subdivision. By refining the horizontal grids, the singularity owing to the point source is minimized and the topography is simulated. By recoarsening the horizontal grids, the number of grid cells is reduced significantly and computational efficiency is improved. Model tests show that the proposed method solves the singularity problem and reduces the number of grid cells by 80% compared to the uniform grid refinement. 展开更多
关键词 direct current resistivity method mesh refinement and recoarsement finiteelement method
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An Empirical Direct Tunneling Current Expression for Ultra-Thin Oxide nMOSFETs 被引量:2
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作者 张贺秋 许铭真 谭长华 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2004年第5期516-519,共4页
An empirical expression for the direct tunneling (DT) current is obtained.This expression can be used to calculate the DT current for nMOSFETs with ultra thin oxide when the oxide thickness is considered as an adjust... An empirical expression for the direct tunneling (DT) current is obtained.This expression can be used to calculate the DT current for nMOSFETs with ultra thin oxide when the oxide thickness is considered as an adjustable parameter.The results have good agreement with the experimental data.And the oxide thickness obtained is less than the value acquired from the capacitance voltage( C V )method. 展开更多
关键词 direct tunnel current NMOSFETS ultra thin
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Direct Tunneling Currents Through Gate Dielectrics in Deep Submicron MOSFETs 被引量:2
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作者 侯永田 李名复 金鹰 《Journal of Semiconductors》 EI CAS CSCD 北大核心 2002年第5期449-454,共6页
A direct tunneling model through gate dielectric s in CMOS devices in the frame of WKB approximation is reported.In the model,an im proved one-band effective mass approximation is used for the hole quantization, wher... A direct tunneling model through gate dielectric s in CMOS devices in the frame of WKB approximation is reported.In the model,an im proved one-band effective mass approximation is used for the hole quantization, where valence band mixing is taken into account.By comparing to the experiments, the model is demonstrated to be applicable to both electron and hole tunneling c urrents in CMOS devices.The effect of the dispersion in oxide energy gap on the tunneling current is also studied.This model can be further extended to study th e direct tunneling current in future high-k materials. 展开更多
关键词 MOSFET direct tunneling current quantum effec t gate dielectrics
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一种交叉倍压型高增益DC/DC变换器 被引量:1
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作者 秦明 冯耀星 +1 位作者 常忆雯 王克文 《电机与控制学报》 EI CSCD 北大核心 2024年第1期120-130,共11页
针对光伏发电、燃料电池发电等领域对高增益直流变换器的需求,以两相交错并联升压变换器为研究对象,由2个含有电感的倍压单元组合设计出实现电压提升的交叉倍压结构,据此提出了一种新颖的交叉倍压型高增益DC/DC变换器。该变换器可实现(3... 针对光伏发电、燃料电池发电等领域对高增益直流变换器的需求,以两相交错并联升压变换器为研究对象,由2个含有电感的倍压单元组合设计出实现电压提升的交叉倍压结构,据此提出了一种新颖的交叉倍压型高增益DC/DC变换器。该变换器可实现(3n+4)/(1-d)倍的高电压增益(1∶n为耦合电感匝数比,d为变换器占空比),且具有电路器件的低电压应力特性。对于漏感引起的开关管电压尖峰问题,引入了钳位电容构成释放漏感能量通道,同时提升了输出电压。介绍了新型交叉倍压型高增益变换器的拓扑结构,分析了变换器各模态的工作过程,推导了电压增益、输入电流纹波及各器件电压应力等稳态特性,并搭建样机进行实验研究,验证了该直流变换技术方案的可行性和先进性。 展开更多
关键词 dc/dc变换器 高增益 低输入电流纹波 交叉倍压 交错并联 耦合电感
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模块化高压大容量DC/DC变换器综述 被引量:2
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作者 张书鑫 赵若凡 刘鸿鹏 《东北电力大学学报》 2024年第1期52-60,共9页
随着新能源发电占比增加和电网规模的不断扩大,直流输电系统的容量不断提升,含有不同电压等级的直流电网是未来发展的必然趋势。在此背景下,DC/DC变换器作为直流电网关键设备,在多电压等级互联场景中发挥着重要作用。文中首先对已有的... 随着新能源发电占比增加和电网规模的不断扩大,直流输电系统的容量不断提升,含有不同电压等级的直流电网是未来发展的必然趋势。在此背景下,DC/DC变换器作为直流电网关键设备,在多电压等级互联场景中发挥着重要作用。文中首先对已有的模块化高压大容量DC/DC变换器进行归纳、分类和比较,然后阐述了目前模块化高压大容量DC/DC变换器的拓扑结构、工作原理与特点,并针对其特点提出了不同变换器的适用场景,最后对未来的研究方向提出了建议。 展开更多
关键词 柔性直流输电 直流电网 模块化多电平换流器 模块化高压大容量dc/dc变换器
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