共查询到20条相似文献,搜索用时 0 毫秒
1.
Guo Pengju Chen XuedongGuan Weihe Cheng HuayunJiang Heng 《Journal of magnetism and magnetic materials》2011,323(20):2474-2477
The surface magnetic field intensity Hp(y) of low-carbon steel plate specimen was measured after tensile test and unloading; variation of Hp(y) was studied. It was found that Hp(y) signals first decreased with increase in stress, and then reversed to the initial field when the stress was greater than 160 MPa. Under yield stress, Hp(y) reached its maximum, and then decreased slightly with further increase in stress. The initial magnetic signals have great impact on the variation of magnetic field. 相似文献
2.
在连续波核磁共振实验中,通常采用低频扫场产生重复再现的共振吸收信号。当处于磁场中的射频线圈引线回路等效面积不为零时,简谐扫场必然引起该闭合回路的磁通量变化,由此而产生同频简谐感生电动势并与核磁共振信号叠加共同构成振荡器输出信号。由于扫场上升和下降过程的感生电动势方向相反,从而扫场前半周和后半周所对应的共振吸收测量信号存在差异。实验结果表明:扫场强度及方向对核磁共振测量影响来源于实验测量技术缺陷,而非核磁共振的物理本质。 相似文献
3.
制备了结构为 ITO/PEDOT:PSS/P3HT:PCBM/Ca/Al的聚合物光电池器件,并在不同偏压下,分别测量了器件的光电流和暗电流随外加磁场的变化. 发现随外加磁场增加,光电流增强,暗电流减弱. 从聚合物光电池中光电流和暗电流的产生机制出发,对该现象进行了解释,认为外加磁场可以有效改变单重态极化子对和三重态极化子对之间的相对比例,进而使自由载流子浓度增加. 光生自由载流子浓度增加是光生电流增强的原因,而自由载流子与三重态激子的相互作用导致了暗电流减弱. 开路电压附近,光电流随磁场增加而增强可以近似
关键词:
聚合物光电池
磁场效应
光生电流
极化子对 相似文献
4.
Yu. Yu. Bacherikov N. V. Kitsyuk T. E. Konstantinova A. S. Doroshkevich 《Journal of Applied Spectroscopy》2007,74(3):408-414
The effect of a magnetic pulsed field (MPF) of induction B = 1 T on photoluminescence, electroluminescence, and luminescence
excitation spectra of powdered ZnS doped with CuCl, In, and MnS is investigated. It is shown that MPF treatment of these materials
changes the photoluminescence spectra only in the case of luminophor ZnS:In whereas only the luminescence excitation spectra
change for ZnS:CuCl and ZnS:Mn.
__________
Translated from Zhurnal Prikladnoi Spektroskopii Vol. 74, No. 3, pp. 367–372, May–June, 2007. 相似文献
5.
Tomoaki Miura 《Molecular physics》2020,118(6)
Since 1970s, magnetic field effects (MFEs) on photogenerated radical pairs have been the centre of focus in the field of spin chemistry. The MFE attributes to quantum mechanical interconversion between the singlet and triplet radical pair states and subsequent spin-selective recombination reactions. In this New View article, the author picks up two hot topics studied during the last two decades, which are (i) so-called low field effect (LFE) and (ii) 2J-resonance MFE on fixed distance donor–acceptor linked molecules. In both of the topics, quantum mechanical explanations are given referring to recent reports, and some novel calculations have been carried out for bridging theoretical and experimental data for long-lived radical pairs. For the first topic, time domain calculations of coherent state mixing have been carried out for elucidation of hyperfine (HF) structure dependence of the LFE. For the second topic, Monte Carlo simulations of the torsional motion of polyaromatic linker unit have been carried out for the demonstration of fast decoherence in such rigid molecules. From these considerations, future possibilities of MFE studies on photo-functional materials and biomolecules have been indicated. 相似文献
6.
The magnetic field plays a major role in searching for the chiral magnetic effect in relativistic heavy-ion collisions. If the lifetime of the magnetic field is too short, as predicted by simulations of the field in vacuum, the chiral magnetic effect will be largely suppressed. However, the lifetime of the magnetic field will become longer when the QGP medium response is considered. We give an estimate of the effect, especially considering the magnetic field response of the QGP medium, and compare it with the experimental results for the background-subtracted correlator H at RHIC and LHC energies. The results show that our method explains the experimental results better at the top RHIC energy than at the LHC energy. 相似文献
7.
8.
迄今为止,并没有被普遍接受的液体静态介电常数的微观理论模型, 主要原因是对属于强关联系统的液体中分子之间的取向关联特征仍不十分清楚. 本文基于Weiss分子场理论(WMFT), 对水(water, H2O)、甲醇(methanol, CH4O)、乙醇(ethanol, C2H6O)和正丙醇(1-propanol, C3H8O)等4种极性液体中静态介电常数, 具体为Curie-Weiss常数、Curie温度和Weiss分子场因子随温度变化规律进行分析研究, 得出上述液体中: 1)铁电关联(ferroelectric correlation, FC)和反铁电关联(anti-ferroelectric correlation, AFC)共存, 且FC比AFC强得多, 以及随温度降低FC减弱和/或AFC增强; 2)结构均匀的WMFT不能定量描述上述液体中足够低的温度下反常大的静态介电常数. 可以想象FC和较弱AFC的共存必然导致极性液体中关联序的空间不均匀, 由此作者提出了空间不均匀关联序的粗粒近似的Weiss分子场理论, 并用此理论对上述液体中静态介电常数随温度快速变化的行为进行了解释. 上述结果对深入认知液体物理学, 包括玻璃化转变机制的探索, 无疑是有价值的. 相似文献
9.
In this study, the behavior of a single bubble in a dielectric viscous fluid under a uniform magnetic field has been simulated numerically using the Level Set method in two-phase bubbly flow. The two-phase bubbly flow was considered to be laminar and homogeneous. Deformation of the bubble was considered to be due to buoyancy and magnetic forces induced from the external applied magnetic field. A computer code was developed to solve the problem using the flow field, the interface of two phases, and the magnetic field. The Finite Volume method was applied using the SIMPLE algorithm to discretize the governing equations. Using this algorithm enables us to calculate the pressure parameter, which has been eliminated by previous researchers because of the complexity of the two-phase flow. The finite difference method was used to solve the magnetic field equation. The results outlined in the present study agree well with the existing experimental data and numerical results. These results show that the magnetic field affects and controls the shape, size, velocity, and location of the bubble. 相似文献
10.
S. Djurović Z. Mijatović M. Pavlov R. Kobilarov B. T. Vujičić 《Journal of Applied Spectroscopy》1997,64(5):578-586
Measurements of the additional shift of the Hβ spectral line emitted by a plasma in a magnetic field are performed. The magnitudes
of the shift are distinguished by good reproducibility. The magnetic field strength was 0.5 and 2.1 T. Comparison is made
of the Hβ line profiles recorded in the presence of the magnetic field and without it, all other things being equal. Consideration
is given to a number of possible causes of the additional shift (they include the dependence of the shift on the density of
electrons, their temperature, and on the velocity of the plasma flux). The additional shift of the Hβ line in the presence
of the magnetic field is qualitatively substantiated.
Presented at the 1th Belorussian-Yugoslavian Symposium on the Physics and Diagnostics of Laboratory and Astrophysical Plasmas,
1–3 July, 1996, Misnk.
Institute of Physics, 4, Obradović St., Novi Sad, 21000, Yugoslavia. Translated from Zhurnal Prikladnoi Spektroskopii, Vol.
64, No. 5, pp. 566–574, September–October, 1997. 相似文献
11.
12.
13.
The effect of varying magnetic field on the lithium plasma produced by laser-blow-off technique has been studied. Enhancement in the intensity accompanied with structures was observed for the spectral lines from neutrals, which varied with the intensity of the magnetic field. In the present report we explore the origin of these structures by invoking the role of various atomic processes. 相似文献
14.
用计算机模拟的方法研究了地磁场中带电粒子的运动特性,绘制了粒子轨迹曲线,对粒子运动进行了分析,解释了地磁场的磁瓶效应和辐射带. 相似文献
15.
研究了外加磁场对滤纸上Zn分枝状电解沉积物生长形貌的影响.用金相显微镜和原子力显微镜观察Zn沉积物的显微结构.发现在非饱和浓度下生长的沉积物生长形貌受电解液浓度和滤纸纤维影响,外加磁场对其形貌的影响不明显.在饱和电解液浓度下获得的沉积物分枝分两层,并且贴近滤纸表面的薄层比其上面离滤纸较远的那一层生长快.在饱和浓度电解液情形下,0.40T外加磁场使得沉积物分枝发生明显的螺旋状偏转.在实验基础上结合相关理论,认为外加磁场通过霍尔效应影响滤纸上Zn分枝状电解沉积物形貌.
关键词:
电解沉积
磁场
霍尔效应
生长形态 相似文献
16.
H. S. Eritsyan J. B. Khachatryan M. A. Ganapetyan A. A. Papoyan H. M. Arakelyan 《Journal of Contemporary Physics (Armenian Academy of Sciences)》2008,43(6):282-286
Influence of an external magnetic field and a spatial dispersion of the dielectric permittivity on the irreversibility of waves in magnetoelectric media is considered. Features of the azimuth inhomogeneity at the simultaneous anisotropy of the dielectric permittivity and magnetic permeability in these media are studied. 相似文献
17.
18.
Based on the Dirac equation describing an electron moving in a uniform and cylindrically symmetric magnetic field which may be the result of the self-consistent mean field of the electrons themselves in a neutron star, we have obtained the eigen solutions and the orbital magnetic moments of electrons in which each eigen orbital can be calculated. From the eigen energy spectrum we find that the lowest energy level is the highly degenerate orbitals with the quantum numbers pZ=0, n=0, and m≥0. At the ground state, the electrons fill the lowest eigen states to form many Landau magnetic cells and each cell is a circular disk with the radius λfree and the thickness λe, where λfree is the electron mean free path determined by Coulomb cross section and electron density and λe is the electron Compton wavelength. The magnetic moment of each cell and the number of cells in the neutron star are calculated, from which the total magnetic moment and magnetic field of the neutron star can be calculated. The results are compared with the observational data and the agreement is reasonable. 相似文献
19.