Nuclear Reactions in Micro/Nano-Scale Metal Particles

Low-energy nuclear reactions in micro/nano-scale metal particles are described based on the theory of Bose–Einstein condensation nuclear fusion (BECNF). The BECNF theory is based on a single basic assumption capable of explaining the observed LENR phenomena; deuterons in metals undergo Bose–Einstein condensation. The BECNF theory is also a quantitative predictive physical theory. Experimental tests of the basic assumption and theoretical predictions are proposed. Potential application to energy generation by ignition at low temperatures is described. Generalized theory of BECNF is used to carry out theoretical analyses of recently reported experimental results for hydrogen–nickel system.     

Distinguishable- and indistinguishable-particle descriptions of systems of identical particles

The problem of distinguishability of identical particles is considered from both experimental and theoretical points of view. It is argued that distinguishability has to be defined relative to a definite set of experiments and that the criterion by which the particles are distinguished should be specified. Failure to do so may cause mismatching between theory and experiment. On the theoretical level a distinction is made between indexed- and unindexed-particle theories, indices being unobserved intrinsic properties of the particles. A field theory of indexed particles is constructed and shown to be equivalent to the second quantization formalism, which is an unindexed-particle theory.     

Improving KFR Theory by Dressing Atomic Initial States

This paper is devoted to nonperturbative theoretical treatments for the above-thresholdionization (ATI) phenomena. It is shown that the bare atomic initial state approximation in Keldysh-Faisal-Reiss (KFR) theory leads to a fundamental theoretical difficulty and thus, has to be modified by properly dressing the atomic initial state with an. appropriate laser-electron interaction term. The analytical result of the improved S-matrix for general situations is obtained and is applied to hydrogen Is-state with linearly polarized laser of various intensities. The numerical simulations of our applications indicate that the improved theory is not only more reasonable on theoretical aspect, but also closer to experimental measurements.     

KLn Dielectronic Recombination Process of B- Through He-like Cu Ions

The KLn dielectronic recombination processes of trapped highly charged B-like through He-like Cu ions are studied theoretically, and the theoretical results are used to analyse our previous experimental data at Heidelberg electron beam ion trap （EBIT）. The theoretical resonant positions agree with the experimental resonant positions to a precision of 0.4%, in comparison with the resonant positions of those highest peaks between theory and experiment. The experimental spectra are then fitted using a formula with the theoretical resonant energies and strengths, the result shows good overall agreement between theory and experiment over a wide electron energy range. The distribution of highly charged states is obtained from the fitting parameters.     

向列型液晶分子理论中的短程关联

本文提出了向列型液晶的格胞理论,为研究分子短程关联提供一个可计算的理论模型。对PAA作了数值计算。理论值较其他理论有不同程度的改进。讨论了分子关联对计算结果的影响以及格胞理论与其他理论的联系。 关键词：     

Anomalous Internal Conversion as a Clue to Solving the <Superscript>209</Superscript>Bi Puzzle

A numerical analysis of the specific-difference (SD) method for eliminating the Bohr–Weisskopf effect in the theory of hyperfine splitting is performed within a more general theory of anomalous nuclear moments. The limiting accuracy of the SD method is demonstrated. In analyzing experimental data on the hyperfine splitting in H- and Li-like ions of ²⁰⁹Bi, it is found that the disagreement between theoretical and experimental results that was reported recently was due to going beyond this theoretical accuracy. Prospects of further experimental and theoretical studies in these realms are discussed.     

光激励硅微机械谐振器的振幅分析及计算

分无镀膜(或镀膜很薄)和有较厚镀膜两种情况,对硅微谐振器的光激励振幅进行了分析计算.针对有较厚镀膜的硅微谐振器,在理论分析的基础上,提出了一种新的光激振幅计算模型,理论计算与实验测试值吻合得很好.     

A model for steady-state large-volume plasma generation

A simple scheme for generating a uniform, steady-state, large-volume plasma is presented. The weakly magnetized plasma is created by direct ionization of the background gas by low-energy electrons generated from thermionic filaments. An annular arrangement of the filaments ensures a uniform plasma density in the radial direction as predicted by theory. Experiments have been performed to characterize the plasma generated in such a configuration. In order to explain the experimental observation, a bulk plasma theory based on plasma transport by means of cross-field diffusion is developed. As assumed in the theoretical model, the experimental measurements indicate a uniform plasma density along the axis. Both the theory and experiment indicate that the plasma density is a function of the square of the external magnetic field. The theory also predicts the plasma density to be proportional to the neutral density to the two-thirds power, in agreement with the experimental data. The experimental data agree well with theoretical prediction for a broad range of system parameters     

TRANSIENT ANALYSIS OF RING-STIFFENED COMPOSITE CYLINDRICAL SHELLS WITH BOTH EDGES CLAMPED

A theoretical method is developed to investigate the effects of ring stiffeners on vibration characteristics and transient responses for the ring-stiffened composite cylindrical shells subjected to the step pulse loading. Love's thin shell theory combined with the discrete stiffener theory to consider the ring stiffening effect is adopted to formulate the theoretical model. The ring stiffeners are laminated with a composite material and have a uniform rectangular cross-section. The Rayleigh-Ritz procedure is applied to obtain the frequency equation. The modal analysis technique is used to develop the analytical solutions of the transient response. The analysis is based on an expansion of the loads, displacements in the double Fourier series that satisfy the boundary conditions. The effect of stiffener's eccentricity, number, size, and position on transient response of the shells is examined. The theoretical results are verified by comparison with FEM results.     

Leptonic decays of hadrons

The theory of semi-leptonic weak interactions is reviewed and confronted with present experimental data. The theoretical points emphasized are the basic tenets of the Cabibbo theory, the algebra of currents, and the relevance of strong interaction symmetries to the weak semi-leptonic amplitudes. The experimental data is discussed in detail, and future lines of investigation, necessary for testing detailed theoretical predictions and for resolving outstanding questions, are indicated.     

Confinement in a three-dimensional Yang–Mills theory

We show that, starting from known exact classical solutions of the Yang–Mills theory in three dimensions, the string tension is obtained and the potential is consistent with a marginally confining theory. The potential we obtain agrees fairly well with preceding findings in the literature but here we derive it analytically from the theory without further assumptions. The string tension is in strict agreement with lattice results and the well-known theoretical result by Karabali–Kim–Nair analysis. Classical solutions depend on a dimensionless numerical factor arising from integration. This factor enters into the determination of the spectrum and has been arbitrarily introduced in some theoretical models. We derive it directly from the solutions of the theory and is now fully justified. The agreement obtained with the lattice results for the ground state of the theory is well below 1% at any value of the degree of the group.     

光纤准直器高回波损耗的理论分析与研究

在高斯光束传输理论的基础上，利用矩阵光学 原理和高斯光束耦合理论得出了斜面耦合自聚焦透镜型光纤准直器的回波损耗的数学表达式。分析了发迹光纤准直器的参数而引起回波损耗变化的原因。实验结果与理论分析比较吻合。     

On a reinterpretation of decay experiments

Discussion of the basic formula conventionally used to interpret decay measurements shows that it is incompatible with the accepted physical interpretation of quantum mechanics. Two alternative theoretical correlates of the actual experiments are discussed. The first assumes a sequence of observations performed on the same object, each causing a collapse of the wave function. The second theory constructs a time-of-sojourn operator on the assumption that the protracted interaction between object and measurement apparatus is “gentle.” The first theoretical formula is developed with the result that the decay probability shows an asymptotic decrease which is at least exponential, contrary to the conventional theory.     

Experimental tests of relativistic gravity

The confrontation between Einstein's gravitation theory and experimental results, notably binary pulsar data, is summarized and its significance discussed. Experiment and theory agree at the 10⁻³ level or better. All the basic structures of Einstein's theory (coupling of gravity to matter; propagation and self-interaction of the gravitational field, including in strong-field conditions) have been verified. However, the theoretical possibility that scalar couplings be naturally driven toward zero by the cosmological expansion suggests that the present agreement between Einstein's theory and experiment might be compatible with the existence of a long-range scalar contribution to gravity (such as the dilaton field, or a moduli field, of string theory). This provides a new theoretical paradigm, and new motivations for improving the experimental tests of gravity.     

Two-dimensional disordered lattice networks with substrate

The paper deals with the development of a theory for describing two-dimensional (2D) random lattice networks of resistors with a particular topology. We consider a 2D anisotropic random lattice where each node of the network is connected to a reference node (substrate) through a given random resistor. This topology is of great interest both for theoretical and practical applications. Moreover, the theory is able to take into account the similar, but more interesting problem with a capacitive coupling with the substrate. The analytical results allow us to obtain the average behaviour of such networks, i.e. the electrical characterisation of the corresponding physical systems. This effective medium theory is developed starting from the properties of the lattice Green's function of the network and from an ad hoc mean field procedure. An accurate analytical study of the related lattice Green's functions has been conducted obtaining closed-form results expressed in terms of elliptic integrals. All the theoretical results have been verified by means of numerical Monte-Carlo simulations obtaining a remarkably good agreement between numerical and theoretical values, both in resistive and capacitive systems.     

液氮冲击压缩特性的理论计算

 用修正的WCA理论计算了液氮冲击压缩至70 GPa的一次冲击Hugoniot数据。计算中引入与体系比容有关的分子离解因子，计算结果表明，在33GPa以上液氮体系发生的相变为分子离解相变，该过程对体系热力学状态有较大影响，分子离解是对冲击能量的吸收过程，导致体系冲击压力和温度增长率下降。     

Approximative methods in the semiclassical theory of multiphoton processes

The present work aims at giving a theoretical background for the several theoretical methods existing in the literature describing multiphoton processes. Within the framework of the semiclassical theory a general expression for the multiphoton transition probability is given — using the formal time-dependent theory of scattering and the general properties of the Schrödinger equation of the problem. The amplitude of the multiphoton transition is a generalisation of the stationary transition operator for the non-stationary case. Using the general expression of the transition probability we compare the different non-perturbative approaches with the perturbation theory and establish the limits of their applicability.

     

Heat capacity of square-well fluids of variable width

We have obtained by Monte Carlo NVT simulations the constant-volume excess heat capacity of square-well fluids for several temperatures, densities and potential widths. Heat capacity is a thermodynamic property much more sensitive to the accuracy of a theory than other thermodynamic quantities, such as the compressibility factor. This is illustrated by comparing the reported simulation data for the heat capacity with the theoretical predictions given by the Barker-Henderson perturbation theory as well as with those given by a non-perturbative theoretical model based on Baxter's solution of the Percus-Yevick integral equation for sticky hard spheres. Both theories give accurate predictions for the equation of state. By contrast, it is found that the Barker-Henderson theory strongly underestimates the excess heat capacity for low to moderate temperatures, whereas a much better agreement between theory and simulation is achieved with the non-perturbative theoretical model, particularly for small well widths, although the accuracy of the latter worsens for high densities and low temperatures, as the well width increases.     

矩形三合板的稳定问题

一.引言 矩形三合板的稳定问题为高速飞机结构设针中经常遇到的实验问题,本文根据[1]所得的一般方程配合边界条件以求解。文中处理在一个方向受有均匀分布载荷、四边简支的矩形板及两边简支两边自由的矩形板,在形变初起的情况下若仅求临界载荷以供设计用则方程可以考虑作为線性,因之可以藉双三角函