对《大学物理》论文“关于拉比强信号理论的疑问和思考解答”再讨论

本文对《大学物理》论文“关于拉比强信号理论的疑问和思考解答”中讨论的问题进行了重新讨论,其理论推导更简洁,物理解释更准确.通过本文我们再次强调,在量子理论中,描述状态的不是概率,而是概率幅.概率相同的状态,概率幅可以不同,从而状态不同.

平面电磁波对导体的辐射压强

当单色平面电磁波垂直入射到可导电的平面镜上时,理论分析了电磁波给平面镜施加的安培力作用以及由此产生的辐射压强.并得到了辐射压强的具体表达式.

红外及太赫兹辐照下细胞膜生物效应的研究进展

太赫兹电磁波辐照,包括其短波段红外波辐照,因具有无创和非电离特性在生物科学中展现出广泛和重要的应用前景.细胞膜是生物细胞保持完整性和内稳态的重要生物屏障,也是太赫兹辐照时电磁场首先作用到的细胞结构,细胞膜对电磁场的响应是大部分太赫兹生物效应产生的机理.本文首先论述了太赫兹辐照应用的安全性及其在生命医药、神经调节以及人工智能领域中应用的新前景,然后从太赫兹电磁辐照下磷脂膜的介电响应特性、细胞膜离子通道蛋白的离子跨膜输运、磷脂膜上大分子及离子的跨膜输运、以及太赫兹辐照下细胞膜生物效应的潜在应用和作用四方面,对太赫兹电磁辐照下细胞膜生物效应领域的研究发展进行系统论述,同时介绍了太赫兹电磁辐照时能够开启细胞膜上压控钙离子通道、压控钾离子通道和主动运输的钙离子通道、以及在磷脂膜上产生亲水孔等科学发现.最后,总结并展望了太赫兹辐照下细胞膜生物效应研究的努力方向.

Role of Ni(NO_3)_2 in the preparation of a magnetic coal-based activated carbon

The role of Nil（NO3）2 in the preparation of a magnetic activated carbon is reported in this paper. Magnetic coal-based activated carbons （MCAC） were prepared from Taixi anthracite with low ash content in the presence of Ni（NO3）2. The MCAC materials were characterized by a vibrating sample magnetometer （VSM）, X-ray diffraction （XRD）, a scanning electric microscope （SEM）, and by N2 adsorption. The cylindri- cal precursors and derived char were also subjected to thermogravimetric analysis to compare their behavior of weight losses during carbonization. The results show that MCAC has a larger surface area （1074 m21g） and a higher pore volume （0.5792 cm3/g） with enhanced mesopore ratio （by about 10~）. It also has a high saturation magnetization （1.6749 emu/g） and low coercivity （43.26 Oe）, which allows the material to be magnetically separated. The MCAC is easily magnetized because the nickel salt is con- vetted into Ni during carbonization and activation. Metallic Ni has a strong magnetism on account of electrostatic interaction. Added Ni（NO3）2 catalyzes the carbonization and activation process by accelerat- ing burn off of the carbon, which contributes to the development of mesopores and macropores in the activated carbon.

Gravitational Shielding Effect in Gauge Theory of Gravity

In 1992,E.E.Podkletnov and R.Nieminen found that under certain conditions,ceramic superconductor with composite structure reveals weak shielding properties against gravitational force.In classical Newton's theory of gravity and even in Einstein's general theory of gravity,there are no grounds of gravitational shielding effects.But in quantum gauge theory of gravity,the gravitational shielding effects can be explained in a simple and natural way.In quantum gauge theory of gravity,gravitational gauge interactions of complex scalar field can be formulated based on gauge principle.After spontaneous symmetry breaking,if the vacuum of the complex scalar field is not stable and uniform,there will be a mass term of gravitational gauge field.When gravitational gauge field propagates in this unstable vacuum of the complex scalar field,it will decays exponentially,which is the nature of gravitational shielding effects.The mechanism of gravitational shielding effects is studied in this paper,and some main properties of gravitational shielding effects are discussed.

Geometry Is the Common Thread in a Grand Unified Field Theory

The consequence of the wave-particle duality is a pointer to the fact that everything in the universe, including light and gravity, can be described in terms of particles. These particles have a property called spin. What the spin of a particle really tells us is what the particle looks like from different directions, in other words it is nothing more than a geometrical property. The motivation for this work stems from the fact that geometry has always played a fundamental role in physics, macroscopic and microscopic, relativistic and non-relativistic. Our belief is that if a GUT （Grand Unified Theory） is to be established at all, then geometry must be the common thread connecting all the different aspects of the already known theories. We propose a new way to visualize the concept of four-dimensional space-time in simple geometrical terms. It is observed that our time frame becomes curved, just as the space-frame, in the presence of a massive gravitating body. Specifically, in the event horizon of a black hole, where time seems to grind to a halt for external observers, the time frame appears to curve in on itself, forming an imaginary loop. This results in extreme time dilation, due to the strong gravitational field. Finally we adopt a descriptive view of a GUT called Quantum Necklace GUT which attempts to connect gravity together the other three fundamental forces of nature, namely the strong, weak and electromagnetic interactions.

Large Detuning Limit for the Multipartite Systems Interacting with Electromagnetic Fields

We study the dynamics of the multipartite systems nonresonantly interacting with electromagnetic fields, focusing on the large detuning limit for the effective Hamiltonian. Due to the many-particle interference effects, the more rigorous large detuning condition for neglecting the rapidly oscillating terms for the effective Plamiltonian should be △ 〉〉 N^1/2 g, instead of △ 〉〉 g usually used in the literature even in the case of multipartite systems, with N the number of microparticles involved, g the coupling strength, A the detuning. This result is significant since merely the satisfaction of the original condition will result in the invalidity of the effective Hamiltonian and the errors of the parameters associated with the detuning in the multipartite case.