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1. chinaXiv:202109.00068 [pdf]

Fluidic Endogenous Magnetism and Magnetic Monopole Clues from Liquid Metal Droplet Machine

Zhou, Ying-Xin; Zu, Jia-Sheng; Liu, Jing
Comment:31 Pages, 14 Figures
Subjects: Physics >> Electromagnetism, Optics, Acoustics, Heat Transfer, Classical Mechanics, and Fluid Dynamics

磁和磁单极子是物理学中的经典问题。传统磁体通常由刚性材料组成,在回答极端问题时可能面临挑战。这里,我们首次从不同于刚性磁体的导电性流体物质出发,提出通过调控液态金属机器来产生流态化内生磁性并由此构造磁单极子。基于理论解释和概念性实验证据,我们阐明了当溶液中的镓基液态金属在电驱动下发生旋转时,其内部会形成一个内生磁场,这很好地解释了两个这样分离的金属液滴能很容易融合在一起的实验现象,原因在于二者通过各自对应的N极和S极相互吸引。此外,我们还阐明了自驱动型液态金属机器也以一种内生流态化磁体出现且具有电磁同源性;当溶液中的液态镓吞食铝时,会形成一个旋转马达和在体动态变化的电荷分布,从而在内部产生内生磁性;这就解释了运动中的液态金属马达之间经常发生反射性碰撞和吸引性融合的现象,这两种现象分别是由于马达之间N极和S极的动态调整引起的。最后,我们设想可通过这种流态化内生磁体制造磁单极子,并提出了实现这一目标的四条技术路线:1. 匹配液态金属机器的内部流场;2. 基于外电场效应与磁场的叠加效应;3. 借助磁颗粒与液态金属马达之间的复合结构;4. 化学途径,如通过原电池反应。总的来说,本文理论和提供的实验证据揭示了液态金属机器作为流体型内生磁体的机制,并指出了实现磁单极的一些有希望的途径。在不久的将来,在此基础上建立一些非传统型磁电器件和应用是可能的。

submitted time 2021-09-27 Hits1383Downloads167 Comment 1

2. chinaXiv:202109.00023 [pdf]

Spectrum Broadening due to Nonselective Linear Absorption

Zhang, Xingchu ; She, Weilong
Subjects: Physics >> Electromagnetism, Optics, Acoustics, Heat Transfer, Classical Mechanics, and Fluid Dynamics

我们对纳灯近红外波段进行了发射光谱的中性吸收实验,并观察了纳灯发射光谱谱线宽度的变化。我们发现当光的强度因吸收变得很低时,这些发射光谱谱线会发生展宽现象,中性滤波片透过率越低,发射光谱的谱线展宽越明显。这是一种不同于已发现的、新的谱线展宽效应。

submitted time 2021-09-14 Hits703Downloads173 Comment 0

3. chinaXiv:202010.00004 [pdf]

REBCO短样经热处理后的临界电流能力测试与性能退化情况分析

Lang Qin; QL Wang; Lei Wang; HB Sun; JH Liu
Subjects: Physics >> Electromagnetism, Optics, Acoustics, Heat Transfer, Classical Mechanics, and Fluid Dynamics

REBCO超导磁体制作过程中,需要使用桥接连接相邻的双饼,桥接部位REBCO带材经过高温焊接过程,性能可能发生退化。本论文对REBCO材料性能退化进行了实际测试,并简单介绍了其原因。实验通过高温热处理来模拟REBCO带材桥接时的高温过程,获得了经过不同温度与时长热处理后的REBCO短样,并在液氮条件下进行了临界电流能力测试,与未经热处理的REBCO带材进行对比,分析了几种带材性能退化的程度及在实际磁体组装中的影响。本论文的结论能够对REBCO带材的处理、接头的工艺和磁体的制作起到一定积极作用。

submitted time 2020-10-12 Hits6345Downloads924 Comment 0

4. chinaXiv:201905.00050 [pdf]

基于单极感应问题的多极感应实验

张学亮
Subjects: Physics >> Electromagnetism, Optics, Acoustics, Heat Transfer, Classical Mechanics, and Fluid Dynamics

针对单极感应之谜,本文注意到磁力线是闭合线,利用洛伦茨力概念首先证明N与M两种对立观点都能够合理解释自法拉第时期以来典型的、有较大影响的单极感应实验。并采用等效电路和比较简明的方法推演出单极感应实验测量回路中感应电动势的一般表达式,说明单极感应问题至今未果的原因是实验采用的轴对称磁体外围磁场特殊的对称性分布结构,且分布结构不随磁体旋转而改变造成的。也说明单极感应实验本身无法解决单极感应问题。介绍了一种多极感应实验方案与实验结果,结合实验磁体外围磁场分布状况,同样用N与M两种观点对照分析了实验结果,得出了法拉第与韦伯当年的单极感应实验测量回路中的感应电动势是由磁体外相对于实验室参照系静止的线段产生的结论,该结论与M观点的结论一致。

submitted time 2019-05-08 Hits16255Downloads1302 Comment 0

5. chinaXiv:201904.00071 [pdf]

湍流手性:可逆系统的平衡与非平衡有螺系综

朱建州
Subjects: Physics >> Electromagnetism, Optics, Acoustics, Heat Transfer, Classical Mechanics, and Fluid Dynamics
Subjects: Physics >> Geophysics, Astronomy, and Astrophysics

研究基于修改Navier-Stokes方程而得到可逆守恒系统的有螺湍流研究思路和理论。讨论三维可压缩湍流统计力学分析及螺度控制力热声问题。构建了一个非平衡系综的有螺可逆系统。最后简要讨论工程应用。

submitted time 2019-03-31 Hits12306Downloads1377 Comment 0

6. chinaXiv:201901.00071 [pdf]

Clinical study on Transcranial magnetoelectric encephalopathy treatment instrument treatmenting parkinson’s disease

Qiang Tang; Wei Zou; Zuodong Sun; Kang Li; Wuyi Sun; Wenhua Wang; Yanli Xing; Xueping Yu; Jing Bai; Xiuying Teng; Yan Hou
Subjects: Medicine, Pharmacy >> Clinical Medicine
Subjects: Physics >> Electromagnetism, Optics, Acoustics, Heat Transfer, Classical Mechanics, and Fluid Dynamics

[Objective] Evaluate on the treatment efficacy and safety for transcranial magnetoelectric encephalopathy treatment instrument (brand name: AOBO Parkinson’s Treatment Instrument) treatmenting parkinson's disease. [Methods] Use methods of double center,randomized, double blind, self crossover, 22 Parkinson’s patients who met the inclusion criteria were randomly divided into A group and B group, then were carried on the curative effect analysis, and were observed therapeutic effect. [Results] The treatment group of 22 cases, basically cured in 0 cases, markedly effective in 9 cases, effective in 8 cases, ineffective in 5 cases. The total efficiency rate and total effective rate were 40.91% (9/22) or 77.27% (17/22) respectively. The control group of 22 cases, basically cured in 0 cases, markedly effective in 2 cases, effective in 3 cases, ineffective in 17 cases. The total efficiency rate and total effective rate were 9.09% (2/22) or 22.73% (5/22) respectively, the total effective rate and total effective rate in the treatment group were higher than those in the control group, the difference was statistically significant (P<0.05). Among them, the main symptoms of resting tremor, rigidity, bradykinesia, evaluation, the treatment group has significant difference (P<0.01); There was no significant difference in the control group (p>0.05); There was significant difference between the treatment group and the control group (p<0.05). [Conclusions] Transcranial magnetoelectric stimulation can significantly improve resting tremor, muscle rigidity, bradykinesia in patients with Parkinson’s disease and other symptoms, and the use of safety. "

submitted time 2019-01-15 Hits26290Downloads1631 Comment 0

7. chinaXiv:201901.00070 [pdf]

重复经颅磁电刺激对海人酸致痫鼠的疗效研究

张旺; 王孝义; 郭洪渠; 宋媛媛; 王爱丽; 孙作东; 沈红
Subjects: Medicine, Pharmacy >> Clinical Medicine
Subjects: Physics >> Electromagnetism, Optics, Acoustics, Heat Transfer, Classical Mechanics, and Fluid Dynamics

目的 探讨经颅磁电刺激(TMES)疗法对海仁酸(KA)致颞叶癫痫鼠的疗效。 方法 62只大鼠按照随机数字表法分为预处理组(共32只)和治疗组(共30只),预处理组再分为4个小组,分别给予治疗仪最大电流强度(MCI) 0%,25%,50%,75%的电流刺激,确定本实验条件下的最佳刺激参数。治疗组再分为3个小组,每组10只。2组(癫痫刺激组、癫痫非刺激组)为符合纳入标准的癫痫模型大鼠,刺激组刺激参数为预处理组确定出的最佳刺激参数;非刺激组大鼠刺激前后处理与刺激组相同,但治疗仪无有效的能量输出。第3组对照组为未造模对照大鼠。3组大鼠均给予每天1次,40 min/次,共14 d的刺激。记录并比较3组大鼠行为学、电生理学及组织学变化,以评估TMES疗法对癫痫大鼠的疗效。 结果 50%MCI为最佳刺激强度。癫痫刺激组大鼠癫痫波出现的频率明显低于癫痫非刺激组大鼠[(30.210 ±4.580)次/min vs. (31.380 ± 4.247)次/min],差异有统计学意义(t=3.235,P=0.001)。Timm染色结果提示3组大鼠染色评分差异有统计学意义(F=17.429, P=0.000),癫痫刺激组大鼠海马齿状回的内分子层Timm染色评分较癫痫非刺激组明显减轻,差异有统计学意义(P<0.05)。结论 TMES疗法可通过改善癫痫大鼠海马齿状回内分子层组织学变化程度来影响齿状回神经元环路的形成,进而降低癫痫脑电波的发作频率。

submitted time 2019-01-02 Hits13918Downloads1716 Comment 0

8. chinaXiv:201811.00044 [pdf]

Fast_tracking_moving_object_using_single_pixel_imaging

时东锋
Subjects: Physics >> Electromagnetism, Optics, Acoustics, Heat Transfer, Classical Mechanics, and Fluid Dynamics

Successive images of a scene are captured and then further processed to achieve the moving object tracking. However, due to modulation rate limitations of the spatial light modulator in single-pixel imaging (SPI) system, the imaging frame rate cannot meet the high-resolution and real-time requirements for object tracking. In this paper, we demonstrate a fast object tracking technique based on SPI with an ultra-low sampling rate that is independent of imaging. We construct modulation information that satisfies the projection conditions and can transform 2D images into 1D projection curves. The 1D projection curves, which provide the location information of the moving object, can be obtained with high resolution in real-time, and then the tracking of the moving object is realized. A background subtraction technique for tracking moving objects that removes static components from a scene is also proposed. The proposed technique is verified by computational simulations and laboratory experiments. In the laboratory experiments, we demonstrate that the proposed method can be used to track moving objects with less than 0.2% of the measurements established by the Nyquist criterion, and it presents a resolution of 256×256 pixels at ~177 fps. The reported technique accelerates the tracking speed of SPI and provides an efficient strategy for remote sensing and biomedical applications.

submitted time 2018-11-11 Hits21171Downloads1500 Comment 0

9. chinaXiv:201712.02150 [pdf]

Feasibility analysis of 1d carbon material in application of negative particle beam diagnostics

Xu,Yongjian
Subjects: Physics >> Electromagnetism, Optics, Acoustics, Heat Transfer, Classical Mechanics, and Fluid Dynamics

An important feature of China Fusion Engineering Test Reactor(CFETR) project is represented by the additional heating obtained from the injection of neutral beams based on accelerated negative ions. For the neutral beams based on negative ions, the most important measurements are beam uniformity, beamlet divergence and stripping losses. According to the CFETR requirement, the maximum allowed beam divergence angle and beam non-uniformity are 6 mrad and ±10%,respectively. As 1D carbon tiles have large ratio between perpendicular conductivity and parallel conductivity and high stability, they can be used for beam uniformity and beamlet divergence measurement. This paper presents the investigation of the influence on the response of 1D carbon tile having the thermal characteristics and features of some dedicated diagnostics. Simulations show that it will be possible to verify experimentally whether the beam meets the requirement about the maximum allowed value. This work lays a foundation for design and application of high precision beam diagnostic targets.

submitted time 2017-11-27 Hits12177Downloads1708 Comment 0

10. chinaXiv:201712.01969 [pdf]

红外成像灰度随距离变化的李群表达

李晨曦; 史泽林; 刘云鹏
Subjects: Physics >> Electromagnetism, Optics, Acoustics, Heat Transfer, Classical Mechanics, and Fluid Dynamics
Subjects: Mathematics >> Mathematics (General)

大气对红外辐射传输的影响引起的红外成像灰度变化,是红外目标跟踪应用需要应对的问题。本文的研究目的是对红外成像灰度变化规律进行李群建模,对设计高效、鲁棒的目标跟踪算法有重要意义。首先分析了红外辐射传输模型,并结合红外成像机理,得到红外成像灰度变化模型。进一步从理论上证明了大气影响下红外成像灰度变化规律符合李群结构,提出了红外图像灰度动态变化的一种非欧数学表征。最后根据红外成像灰度变化模型对不同环境下采集到的外场实验数据进行拟合,回归分析结果表明了该模型的准确性,进而说明了本文对红外成像灰度变化规律进行李群表达的合理性。

submitted time 2017-11-26 Hits31845Downloads3206 Comment 0

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