Dependence of the Intensity of the Spectral Lines and the Composition of the Sample and the Plasma Parameters of the Unipolar Arc

The investigation was made of the dependence of the intensity of Tl, Ga, Mo, Mg, Mn, Sn, Bi, Ni, Zn, Pt and Au spectral lines and the plasma parameters (temperature T, electron concentration n_e, degree of 6 ionnization α) from concentration of lithium additive.     

On the problem of the distribution of impurity ions in the F-region of the ionosphere

One-dimensional nonisothermal diffusion in ionospheric plasma (the F-region) is considered in the stationary case. The analysis is carried out for two species of positive ions with allowance for the ionization and recombination processes and the effect of gravity. A system of two coupled equations is derived for the concentrations of the electrons and ions. A transition is made to the case when the ions which determine dissociative recombination are impurity ions. For this case criteria are presented whose fulfilment causes the distribution that has been found to coincide with that obtained by Mange [9] without allowance for photochemical processes.     

干涉仪系统传递函数测量及影响因素的分析

波前功率谱密度(PSD)被用于评价惯性约束聚变(ICF)激光驱动器光学元件中频段的波前误差。干涉仪对PSD较高空间频率分量的测量存在失真效应,可通过干涉仪系统传递函数(STF)的检测标定来获得真实的波前PSD分布。采用台阶板位相比较法测得大口径菲索相移干涉仪检测系统在透射和反射检测情形下的传递函数。对传递函数测试算法进行了比较分析,明确了干涉仪系统zoom倍率的改变等因素对传递函数测量的影响,为波前PSD的准确检测奠定了基础。     

On the predictability of the positions of the convergence zones in the ocean

The disagreement between the experimental and calculated positions of the first convergence zone are known from many publications. The most probable cause for such a disagreement, namely, the incorrect specification of the input data for the calculations, is considered. The lack of simultaneity between the hydrological surveys of the region and the acoustic experiments is emphasized. The experimental data obtained by the author in five ocean regions are presented. These data characterize the diurnal variability of the distance from the source to the nearest boundary of the convergence zone. The relations proposed by different researchers for calculating the sound speed from the temperature, salinity, and hydrostatic pressure are analyzed. It is shown that these relations lead to a substantial difference in the estimated depth dependence of the hydrostatic gradient of the sound speed. The position of the first convergence zone is calculated for the propagation conditions determined by vertical temperature and salinity profiles with the subsequent recalculation of these profiles into sound speed profiles by using eight different formulas known from the literature. It is shown that different formulas lead to different values of the distance to the first zone; this difference is substantially greater than that between the calculations and experiment. The necessity of improving the recalculation relations in view of the experimental data on sound propagation in natural oceanic waveguides, including the data on the actual positions of the convergence zones, is emphasized.     

建立力学模型,研究单杠运动中旋转的有关问题

建立相关的力学模型,讨论运动员在单杠旋转运动中如何增加旋转能量,杠的刚柔性对旋转运动的影响和伸展、收缩的最佳时机选择等若干问题．充分展示了力学模型对研究问题的重要意义和作用．     

Application of the method of collective coordinates the the quantisation of the two-dimensional higgs model

A comprehensive analysis of the application of the method of collective coordinates to the two dimensional Higgs model is given. First the instanton solution is derived, and the geometry of configuration space, and the construction of Schrodinger wave functionals are discussed. It is then explicitly verified that the Goldstone mode is the projection of the vacuum state onto the generator of the broken symmetry. The elimination of this Goldstone mode by means of the unitary gauge condition is demonstrated to the the crucial point in the construction of a consistent perturbation procedure. The parameter of the broken symmetry group is then used as the collective coordinate for field configurations around a minimum of the interaction. Throughout, the discussion is sufficiently detailed in order to facilitate the application of the method to other fields.     

On the Locality of the No Hair Conjecture and the Measure of the Universe

We reanalize the recently proposed proof by Jensen and Stein-Schabes [1] of the No Hair Theorem for inhomogeneous spacetimes, putting a special emphasis on the asymptotic behaviour of the shear and curvature. We conclude that the theorem only holds locally and estimate the minimum size a region should be in order for it to inflate. We discuss in some detail the assumptions used in the theorem. In the last section we speculate about the possible measure of the set of spacetimes that would undergo inflation.     

Detection of the spectra of multicharged ions with time resolution and the determination of the parameters of the hot component of the plasma in the case of the magnetic implosion of multiwire arrays

The dynamics of the hot component of the plasma of imploding multiwire arrays has been analyzed using the time behavior of the X-ray spectral lines of multicharge ions. The spectra of H- and He-like aluminum ions with nanosecond time resolution have been detected using electron-optical chronography in experiments on the implosion of multiwire arrays by mega-ampere currents. The simultaneous appearance of the resonance lines of H- and He-like ions implies that the hot plasma whose electron temperature is higher than 0.5 keV has existed on the axis before the implosion of the main mass of the liner. The further dynamics of the intensity of the lines is primarily attributed to an increase in the mass of the emitting plasma.     

Calculation of the vacuum condensates of the trace of the energy-momentum tensor

It is shown that a modification of the effective potential proposed by A.A. Migdal and Shifman makes it possble to calculate the vacuum condensates of the trace of the energy-momentum tensor in massless theories in various spacetime dimensions.     

Equivalence of the method of the kinetic equation and the fluctuating-frequency method in the theory of the broadening of spectral lines

A new expression for the Stark profiles of spectral lines in plasma has been obtained by the method of the kinetic equation taking into account the dynamics of the plasma microfield. The result represents a dynamic line profile in the form of simple functionals of a static profile. The relation of the new solution with the known fluctuating-frequency method has been analyzed. It has been shown that this method is a discrete analog of the method of the kinetic equation and passes to the latter method in the limit of the continuous fluctuations. Simple formulas (4), (5), and (21) for dynamic line profiles provide ultrafast calculations of the profiles of spectral lines taking into account the dynamics of the plasma microfield.     

Contributions of the cornea and the lens to the aberrations of the human eye

The relative contributions of optical aberrations of the cornea and the crystalline lens to the final image quality of the human eye were studied. The aberrations of the entire eye were obtained from pairs of double-pass retinal images, and the aberrations of the cornea were obtained from videokeratographic data. Third-order spherical aberration and coma were significantly larger for the cornea than for the complete eye, indicating a significant role of the lens in compensating for corneal aberrations. In a second experiment retinal images were recorded in an eye before and after we neutralized the aberrations of the cornea by having the subjects wear swimming goggles filled with saline water, providing a direct estimate of the optical performance of the crystalline lens.     

Effect of the configuration of the discharge chamber of the plasma focus on the neutron yield

Preliminary probe experiments on the Filippov-type plasma focus with the energy E = 70 kJ and a current of about 1 MA show significant stray currents flowing near the insulator. To suppress them and optimize the discharge circuit, the main discharge chamber elements, i.e., the insulator, anode and cathode liner, were changed. As a result, a 30-fold increase in the setup neutron yield to Y _n = 5· 10¹⁰ neutrons per pulse was detected.     

Determination of the mass spectrum of the bound state in the framework of the relativistic hamiltonian approach

We propose one a variant of calculation of the energy spectrum of bound state systems with relativistic corrections. In the framework of quantum field theory, an expression that takes into account relativistic corrections to the mass of the bound state with a known nonrelativistic pair interaction potential is proposed on the basis of calculating the asymptotic behavior of correlation functions of the corresponding field currents with the necessary quantum numbers. Excluding the time variables allows one to determine nonperturbative corrections to the interaction potential. The following results have been obtained in the framework of this approach. The nonperturbative corrections arising due to the relativistic nature of a system to the interaction Hamiltonian are determined. The dependence of the constituent mass of bound-state forming particles on the free state mass and on the orbital and radial quantum numbers is analytically derived. The energy level shift of muonic hydrogen taking into account relativistic corrections is calculated. The energy spectrum of a wide class of potentials that describe the Coulomb bound state is analytically derived with relativistic corrections. The mass spectrum of the glueballs and the constituent masses of the gluons are analytically calculated taking into account spin-orbit, spin—spin, and tensor interactions. Our numerical results have shown very good agreement with the lattice data. Taking into account nonperturbative and nonlocality characters of interactions, the mass spectrum of the mesons consisting of light-light and light-heavy quarks with orbital and radial excitations is determined. Our results show that good agreement with the experimental data for the slope and the intercept of the Regge trajectory can be obtained only taking into account the nonperturbative and the nonlocal characters of interactions. The dependences of the constituent masses of constituent particles on the masses of a free state are certain. When quarks are light, then the difference between current and valent masses of quarks is greater than valent masses of quarks, and when quarks are heavy, then the difference between these masses is insignificant. One of the alternative variants of taking nonlocality into account has been suggested for the definition of properties of hadrons at large distances. The dependence of the constituent masses of constituent particles on the radius of confinement is determined.     

Kinetics of the maintenance of the epidermis

The epidermis is the outermost layer of skin. It is comprised of keratin-containing cells called keratinocytes. Functionally, the epidermis serves as a physical barrier that can prevent infection and regulate body hydration. Maintenance and repair of the epidermis are important for human health. Mechanistically, these processes occur primarily via proliferation and differentiation of stem cells located in the basal monolayer. These processes are believed to depend on cell-cell communication and spatial constraints but existing kinetic models focus mainly on proliferation and differentiation. To address this issue, we present a mean-field kinetic model that takes these additional factors into account and describes the epidermis at a biosystem level. The corresponding equations operate with the populations of stem cells and differentiated cells in the basal layer. The keratinocytes located above the basal layer are treated at a more coarse-grained level by considering the thickness of the epidermis. The model clarifies the likely role of various negative feedbacks that may control the epidermis and, accordingly, provides insight into the cellular mechanisms underlying complex biological phenomena such as wound healing.     

产生旁瓣的激光波前功率谱密度与焦斑性能分析

 讨论了在放置与不放置焦斑形态控制器件KPP的两种情况下,采用功率谱密度模拟分析有旁瓣焦斑的激光束波前分布的特点,并由此探讨高功率激光驱动器在无旁瓣的聚焦情形下,对入射到打靶透镜的激光束波前畸变量的控制要求。     

Influence of the thickness of the liquid layer on the ratio of the dimensions of a convection cell

A theory is developed for a new type of transition — a change in the ratio of the longitudinal and transverse dimensions of a convection cell as the thickness of a liquid layer is varied. A sudden change in the ratio of the cell dimensions takes place because of a change in the predominant mechanism for excitation of convection. The governing influence of buoyancy forces gives way to one of thermocapillary forces, and they in turn give way to the influence of thermoelectric forces for yet thinner layers. As the layer thickness is reduced gradually at a fixed external heating, the ratio of the dimensions will take on the values 0.7, 0.65, and 1, respectively. Zh. Tekh. Fiz. 68, 7–11 (November 1998)     

On the influence of the voltage pulse profile on the process of particle trapping in the adiabatic trap of the gyrotron

We analyze the process of stabilization of electron beam parameters in a gyrotron for different profiles of the front of the accelerating-voltage pulse and the case of a large space charge trapped in the adiabatic trap. The duration of the portion of the pulse front, within which the electrons are reflected from the magnetic mirror and trapped, is at least an order of magnitude shorter than the entire length of the pulse front and is comparable with the characteristic time of potential oscillation development in the trap at great values of the pitch factor. The results of numerical analysis of the electron beam within the framework of models with finite durations of the voltage pulse front and instantaneous switch-on of the voltage showed that the steady-state values of the beam parameters are only weakly dependent on the pro.le of the pulse front. __________ Translated from Izvestiya Vysshikh Uchebnykh Zavedenii, Radiofizika, Vol. 51, No. 5, pp. 425–433, May 2008.     

Experimental test of the compatibility of the definitions of the electromagnetic energy density and the Poynting vector

It is shown that the generally accepted definition of the Poynting vector and the energy flux vector defined by means of the energy density of the electromagnetic field (Umov vector) lead to the prediction of the different results touching electromagnetic energy flux. The experiment shows that within the framework of the mentioned generally accepted definitions the Poynting vector adequately describes the electromagnetic energy flux unlike the Umov vector. Therefore one can conclude that a generally accepted definitions of the electromagnetic energy density and the Poynting vector, in general, are not always compatible.     

On the Question of the Source of the Apokamp

Technical Physics - The object of this work is the apokamp—a new type of plasma jet, which is formed from a bright offshoot emerging at the bending point of a channel of a high-voltage...