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Schulz claims to have constructed an actively local stochastic theory which violates Bell's inequality. This is false.  相似文献   

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Free electron gas is present in every gas, whether it is of atomic or molecular structure. Since the Maxwell spectrum type is the consequence of only thermal motion of constitutive gas particles; therefore, the presence of electric field leads to change the spectrum of charged particles due to their directed motion. However, it has been shown that in the case of occurrence only of elastic interactions between electrons and neutral gas particles (a condition that has been met in the case of weakly ionized noble gases of a relatively huge volume) the deviation of the gas spectrum of free electrons in the electric field from the Maxwell type is negligible. In such a case, the gas spectrum of free electrons is either of Maxwell type (if the frequency collision value is energy-independent) or of Druyvesteyn type (if the mean free electron path value is energy-independent). The Maxwell and Druyvesteyn distribution types are very similar. The only noticeable difference is that the tail of the Maxwell distribution decreases with the energy exponent to the first degree of energy, and the tail of Druyvesteyn distribution with the energy exponent to the second degree of energy. The aim of this paper is to determine whether the gas spectrum of free electrons in weakly ionized noble gases at small values of the product pd (pressure and inter-electrode distance) follows either the Maxwell's or Druyvesteyn's type, as well as to determine the dependence of spectrum parameters on the product pd. It has been established that better results are obtained on the assumption that the mean value of collision frequency is energy-independent.  相似文献   

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A pseudo-analytical solution technique is proposed to determine the three-dimensional static Green's function for a half space over mixed perfect electric conductor-dielectric wedges. The governing Poisson's equation is solved, using the Kontorovich–Lebedev and Fourier transforms. The solution, expressed in terms of image contributions, consists of an excitation point source, a set of point images in physical space, and two line images located in complex space for each region of the problem geometry. The validity of the proposed technique is confirmed by comparing our results with the existing analytical solutions and those obtained numerically using the using a finite integration code.  相似文献   

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J.C. Caillon 《Physics letters. A》2018,382(46):3307-3312
We have considered electric charge as the fourth component of the particle momentum in five-dimensional space–time. The fifth dimension has been compactified on a circle with an extremely small radius determined from the fundamental physics constants. First, we have given equations in the framework of five-dimensional special relativity and determined the corresponding reduction to four-dimensional space–time. Then, in order to obtain an appropriate charge-to-mass ratio and to avoid the Fourier modes problem, we have considered the propagation of an off-mass shell particle in the five-dimensional space–time which can be interpreted as the motion of an on-mass shell particle in the four-dimensional world we experience. As an example, we have discussed the five-dimensional kinematic equations associated with the electron-positron annihilation process into two photons. Finally, the consequences on the gravitational interaction between two elementary charged particles has been studied. As a main result, we have obtained a unification of Newton's gravitational and Coulomb's electrostatic forces.  相似文献   

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An analytical Volkov's solution of the massless Dirac equation for graphene in the field of slow-light pulse with arbitrary time dependence is obtained. Exact solutions are presented for special cases of monochromatic field and a single-cycle pulse. Following the Fock-Schwinger proper time method, the Green's function for quasiparticles is derived with the account of the influence an external classical electromagnetic wave field.  相似文献   

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Abstract

An analytical chemistry laboratory project to use and evaluate pyridyl‐ and triazine‐containing chelators for spectrophotometric determination of iron is described. The “Iron Project” introduces students to UV‐visible spectrophotometry and Beer's law via hands‐on development and use of spectrophotometric methods for iron. Nine chelators are currently available for use. Students perform their proposed work, culminating in formal papers and posters. Student values of molar absorptivities (?max) and λmax for ligands 1–9 agree with published values to within ±15% (?max) and ±3 nm (λmax) for 75% of results obtained so far. Stoichiometries for Fe(II) chelates of ligands 1–5 are within ±1 mole of ligand of the published ratios. Student work shows a basic understanding of Beer's law as well as a need to improve writing, problem‐solving, and laboratory skills.  相似文献   

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张亚普  达新宇  祝杨坤  赵蒙 《物理学报》2014,63(23):234101-234101
电磁脉冲武器能够通过"前、后门"耦合效应对箱体内部电子元器件及电路板造成损伤,从而对电气电子设备的安全性构成严重威胁,因此,开展箱体电磁屏蔽效能的分析研究具有重要意义.推导了任意入射波条件下电大开孔箱体屏蔽系数的解析解,并在此基础上对箱体屏蔽效能进行了分析研究.首先通过矢量分解,得出任意入射平面波的坐标分量;再基于Cohn模型,获得了电大开孔的等效电偶、磁偶极子;然后通过镜像原理,计算出总的赫兹电矢量位、磁矢量位;最终求得电大开孔箱体内部任意观测点的电场解析解,用于箱体屏蔽系数计算.设计了5组验证性实验,仿真结果表明:该解析算法相对CST的均方误差为11.565 d B,绝对误差为8.015 d B,相关系数为0.921,从而验证了该算法的准确性;解析算法仿真的平均耗时为0.183 s,仅占CST耗时的1/7530,从而验证了该算法的高效性.  相似文献   

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This work investigates the high frequency characteristics of [FeCoB/ZnO]50 multilayers with different ZnO thickness. The results reveal that the Acher’s limit of [FeCoB/ZnO]50 multilayers can be modulated by medium thickness. Increasing medium layer thickness is favorable for breaking through the Acher’s limit. It is found that the differences of Acher’s limit between multilayers and single layers are caused by magnetic interface anisotropy related to interface roughness and some unknown factor.  相似文献   

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石墨烯力学性能的研究对其在半导体技术中的应用是十分重要的,本文基于半连续体模型并结合石墨烯纳米结构特性,通过对原子的描述构建了石墨烯形变分量和位移分量的新关系,从而给出了单层石墨烯结构形变能,并计算了不同尺寸单层石墨烯的杨氏模量值.通过对不同方向杨氏模量的分析,讨论了单层石墨烯的手性行为.结果表明:随着尺寸的增加,单层石墨烯两个方向的杨氏模量分别趋于0.746 TPa和0.743 TPa,当尺寸相同时,两方向杨氏模量的最大差值不超过0.003 TPa,此结果与文献报道结果相符.在小应变情况下,单层石墨烯薄膜呈各向同性,且薄膜尺寸变化对该特性影响不大.该计算结果对研究石墨烯的其它力学特性提供一定的参考价值.  相似文献   

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This paper introduces a hedge operator based fuzzy divergence measure and its application in segmentation of leukocytes in case of chronic myelogenous leukemia using light microscopic images of peripheral blood smears. The concept of modified discrimination measure is applied to develop the measure of divergence based on Shannon exponential entropy and Yager's measure of entropy. These two measures of divergence are compared with the existing literatures and validated by ground truth images. Finally, it is found that hedge operator based divergence measure using Yager's entropy achieves better segmentation accuracy i.e., 98.29% for normal and 98.15% for chronic myelogenous leukocytes. Furthermore, Jaccard index has been performed to compare the segmented image with ground truth ones where it is found that that the proposed scheme leads to higher Jaccard index (0.39 for normal, 0.24 for chronic myelogenous leukemia).  相似文献   

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This paper describes steady‐state ensembles of thermally excited electromagnetic radiation in nano‐scale layered media with a constant non‐vanishing heat flux across the layers. It is shown that Planck's law of thermal radiation, the principle of equivalence, and the laws of wave propagation in layered media, imply that in order for the ensemble of thermally excited electromagnetic fields to exist in a medium consisting of a stack of layers between two half‐space, the net heat flux across the layers must exceed a certain threshold that is determined by the temperatures of the half spaces and by the reflective properties of the entire structure. The obtained results provide a way for estimating the radiative heat transfer coefficient of nano‐scale layered structures.  相似文献   

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Planck's law of thermal radiation is limited to equilibrium systems that have a definite temperature and do not carry any heat flux. Here we extend it to steady‐state systems with a constant heat flux. The obtained formulas explicitly describe the spectrum of thermal radiation in every direction and provide a sound basis for the self‐consistent analysis of radiative heat transport across interfaces, gaps, layered and other important structures.  相似文献   

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