共查询到20条相似文献,搜索用时 187 毫秒
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用恩氏粘度计对某些油品的粘度值进行了实测及分析,并对该粘度的不确定度与非线性误差指标进行了评价,评判了该粘度计的适用范围。 相似文献
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将气轨与粘度计相结合,利用气轨的测速仪测量粘度计砝码匀速下降的速度,以测量液体粘滞系数,该方法既减小了计时误差,又可准确判断系统的运动状态。 相似文献
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本文就VAD—H型高温粘度计的原理及影响测量精度的因素进行了推导,并在实验的基础上讨论了保持测量精度的最佳条件。同时就此仪器对熔融态下玻璃比重的测量进行了探讨。最后给出了几个测量实例。 相似文献
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用Flash模拟液体粘滞系数测定的实验 总被引:1,自引:0,他引:1
本文应用Flash软件模拟制作了医用物理实验一奥氏粘度计法测酒精的粘滞系数,对医用物理实验在仿真领域进行了尝试。介绍了相关操作步骤,其中实验工具、实验步骤可以由学习者自主操作,避免了实物实验中由于人为因素所导致的实验结果不准确。 相似文献
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E. J. Janse van Rensburg 《Journal of statistical physics》2001,102(5-6):1177-1209
A lattice tree at an interface between two solvents of different quality is examined as a model of a branched polymer at an interface. Existence of the free energy is shown, and the existence of critical lines in its phase diagram is proven. In particular, there is a line of first order transitions separating a positive phase from a negative phase (the tree being predominantly on either side of the interface in these phases), and a curve of localization–delocalization transitions which separate the delocalized positive and negative phases from a phase where the tree is localized at the interface. This model is generalized to a branched copolymer which is examined in a certain averaged quenched ensemble. Existence of a thermodynamic limit is shown for this model, and it is also shown that the model is self-averaging. Lastly, a model of branched polymers interacting with one another through a membrane is considered. The existence of a limiting free energy is shown, and it is demonstrated that if the interaction is strong enough, then the two branched polymers will adsorb on one another. 相似文献
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A compact beam-shaping device with a reflective aspherical surface is proposed. The device converts a circular symmetric Gaussian
beam from a laser into a uniform distribution on a target plane. The device consists of a laser, a reflective aspherical surface
formed on the base plane inclined by 45° against the optical axis, and a spacer. The surface is designed for an optical device
used as a transmitter of indoor wireless optical communication, which is one of the promising applications. The designed surface
is obtained by approximation using polynomial. Beam shaping of a simulated surface and a uniform intensity distribution on
the target plane is obtained. The intensity distribution generated by the surface is numerically simulated and evaluated if
the surface is misaligned. It is clarified that the generated distribution is tolerable for the misalignment. 相似文献
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弯曲光纤针尖及其法向力压电探测技术 总被引:1,自引:0,他引:1
本文介绍一种弯曲光纤针尖及其法向力压电探测的新技术.与目前普遍采用的方法不同,弯曲针尖的制作是先利用电阻丝加热,将光纤弯曲成所需的角度,然后再在缓冲氢氟酸中腐蚀成针尖,得到曲率半径为300μm,弯曲角度为120°,长度为500μm的弯曲针尖.同激光或电弧熔拉、弯曲的方法相比,这种方法工艺简单,成本低廉.由弯曲针尖与蜂鸣器压电片组成的悬臂,利用压电片的正、逆压电效应实现弯曲针尖法向力的非光学法探测.实验表明,这种弯尖法向力的探测较直尖切变力具有更高灵敏度,探测距离提高了一倍以上,给实际应用带来很大的便利. 相似文献
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Sayatnova Tamaryan 《Physics letters. A》2011,375(23):2224-2229
Pure three-qubit states have five algebraically independent and one algebraically dependent polynomial invariants under local unitary transformations and an arbitrary entanglement measure is a function of these six invariants. It is shown that if the reduced density operator of a some qubit is a multiple of the unit operator, than the geometric entanglement measure of the pure three-qubit state is absolutely independent of the polynomial invariants and is a constant for such tripartite states. Hence a one-particle completely mixed state is a critical point for the geometric measure of entanglement. 相似文献
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Sylvia Pulmannová 《International Journal of Theoretical Physics》2003,42(7):1413-1423
A noncommutative version of generalized Sasaki projections in pseudoeffect algebras is introduced. It is proved that an ideal in a pseudoeffect algebra is Riesz if and only if it is closed under the right and left Sasaki projections. In lattice ordered pseudoeffect algebras, it is shown that generalized Sasaki projections are one-element sets, and their explicit form is found. It is shown that if a supremum of a normal Riesz ideal in a lattice ordered pseudoeffect algebra exists, it is a central element. These results extend those obtained recently by Avallone and Vitolo for effect algebras. 相似文献
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Based on the PT-symmetric quantum theory, the concepts of PT-frame, PT-symmetric operator and CPT-frame on a Hilbert space K and for an operator on K are proposed. It is proved that the spectrum and point spectrum of a PT-symmetric linear operator are both symmetric with respect to the real axis and the eigenvalues of an unbroken PT-symmetric operator are real. For a linear operator H on Cd, it is proved that H has unbroken PT- symmetry if and only if it has d different eigenvalues and the corresponding eigenstates are eigenstates of PT. Given a CPT-frame on K, a new positive inner product on K is induced and called CPT-inner product. Te relationship between the CPT-adjoint and the Dirac adjoint of a densely defined linear operator is derived, and it is proved that an operator which has a bounded CPT-frame is CPT-Hermitian if and only if it is T-symmetric, in that case, it is similar to a Hermitian operator. The existence of an operator C consisting of a CPT-frame is discussed. These concepts and results will serve a mathematical discussion about PT-symmetric quantum mechanics. 相似文献
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Sujit Nair 《Physica D: Nonlinear Phenomena》2012,241(4):315-325
The goal of this paper is to show that the space-time geodesic approach of classical mechanics can be used to generate a time adaptive variational integration scheme. The only assumption we make is that the Lagrangian for the system is in a separable form. The geometric structure which is preserved in the integration scheme is made explicit and the algorithm is illustrated with simulation for a compact case, a non-compact case, a chaotic system which arises as a perturbation of an integrable system and the figure eight solution for a three body problem. 相似文献
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Simultaneous effects of magnetic field and space porosity on compressible Maxwell fluid transport induced by a surface acoustic wave in a microchannel
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Peristaltic motion induced by a surface acoustic wave of a viscous, compressible and electrically conducting Maxwell fluid in a confined parallel-plane microchannel through a porous medium is investigated in the presence of a constant magnetic field. The slip velocity is considered and the problem is discussed only for the free pumping case. A perturbation technique is employed to analyze the problem in terms of a small amplitude ratio. The phenomenon of a “backward flow” is found to exist in the center and at the boundaries of the channel. In the second order approximation, the net axial velocity is calculated for various values of the fluid parameters. Finally, the effects of the parameters of interest on the mean axial velocity, the reversal flow, and the perturbation function are discussed and shown graphically. We find that in the non-Newtonian regime, there is a possibility of a fluid flow in the direction opposite to the propagation of the traveling wave. This work is the most general model of peristalsis created to date with wide-ranging applications in biological, geophysical and industrial fluid dynamics. 相似文献
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《Physics letters. A》2020,384(15):126301
The entanglement swapping protocol is analyzed in a relativistic setting, where shortly after the entanglement swapping is performed, a Bell test is performed. For an observer in the laboratory frame, a Bell violation is observed between the qubits with the swapped entanglement. In a moving frame, the order of the measurements is reversed, and a Bell violation is observed even though the particles are not entangled, directly or indirectly, or at any point in time. Although the measurement results are identical, the wavefunctions for the two frames are starkly different — one is entangled and the other is not. Furthermore, for boosts in a perpendicular direction, in the presence of decoherence, we show that the maximum Bell violation can occur across non-simultaneous points in time. This is a signature of entanglement that is spread across both space and time, showing both non-local and non-simultaneous aspects of entanglement. 相似文献