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1.
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 ne, degree of 6 ionnization α) from concentration of lithium additive.  相似文献   

2.
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.  相似文献   

3.
We show the scattering matrix associated to the Manakov-Zakharov-Shabat (MZS) system can be factorized as the product of two scattering matrices associated to the Zakharov-Shabat (ZS) system of the Nonlinear Schrödinger (NLS) equation, whenever the initial conditions of the Manakov system have disjoint support. Moreover, if these initial conditions are assumed to be single-lobe, the eigenvalues of the MZS system are purely imaginary.  相似文献   

4.
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.  相似文献   

5.
Sosnin  E. A.  Panarin  V. A.  Skakun  V. S.  Tarasenko  V. F. 《Technical Physics》2018,63(6):924-927
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...  相似文献   

6.
干涉仪系统传递函数测量及影响因素的分析   总被引:1,自引:0,他引:1  
邓燕  柴立群  许乔  徐建程  张宁 《光学技术》2006,32(5):741-743
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。  相似文献   

7.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 53, No. 1, pp. 26–30, July, 1990.  相似文献   

8.
Let G be one of the local gauge groups C(X, U(n)),C (X, U(n)), C(X, SU(n)) or C (X, SU(n)) where X is a compact Riemannian manifold. We observe that G has a nontrivial group topology, coarser than its natural topology, w.r.t. which it is amenable, viz. the relative weak topology of C(X, M(n)). This topology seems more useful than other known amenable topologies for G. We construct a simple fermionic model containing an action of G, continuous w.r.t. this amenable topology.  相似文献   

9.
Translated from Zhurnal Prikladnoi Spektroskopii, Vol. 52, No. 5, pp. 794–798, May, 1990.  相似文献   

10.
On the basis of the classical theory of radiation produced in incomplete Coulomb interaction, a formula is derived for the coefficient of the bremsstrahlung of fully ionized plasma. In the region of rectilinear approximation a comparison is made with the results of the quantum formula derived from the Born approximation. Furthermore, the influence of dispersion upon the emission coefficient is taken into account; some relations for the region of dispersion are given.  相似文献   

11.
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.  相似文献   

12.
We propose a procedure for renormalizing the Casimir energy that makes the steps that are used in the standard renormalization procedure, that is, regularization, subtraction, and deregularization, implicit. The proposed procedure is based on the calculation of a set of convergent sums, each of which is related to the initial divergent sum of the non-renormalized Casimir energy. Next, we construct a system of linear equations that relates this set of convergent sums to the renormalized Casimir energy. The unknown renormalized Casimir energy is obtained as a result of solving this system of equations. In this case, both the calculations of the convergent sums and the subsequent solution of the system of linear equations are performed with a certain (generally speaking, arbitrary) ordered accuracy; thus, the result is also approximate. The proposed procedure is, first, more computationally effective than the standard one, and, second, applicable not only to the problems where a transcendental equation for the spectrum can be written, but also to the problems where the spectrum is known only numerically.  相似文献   

13.
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.  相似文献   

14.
15.
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)  相似文献   

16.
Over the last years there has been increasing evidence that the normal state of the cuprates can not be described adequately with individual quasiparticles within Fermi-liquid theory. While the low-lying excitations in the superconducting state are nevertheless possibly of quasiparticle character, this character vanishes with the loss of superconducting phase coherence when going to the normal conducting state. Generally, this normal state is characterized by strong heterogeneity. In real space this manifests in charge and spin ordering, either static or dynamical, the so-called ‘stripes’. The spectral signatures of various models describing this unusual metallic normal state together with less exotic non-Fermi-liquid models, like the marginal Fermi liquid, will be compared to photoemission spectra with high angular and energy resolution and to results obtained by other methods. Received: 19 March 2002 / Accepted: 2 October 2002 / Published online: 5 February 2003 RID="*" ID="*"Corresponding author. Fax: +49-30/2093-7729, E-mail: christoph.janowitz@physik.hu-berlin.de  相似文献   

17.
 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。  相似文献   

18.
产生旁瓣的激光波前功率谱密度与焦斑性能分析   总被引:3,自引:2,他引:1  
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。  相似文献   

19.
We obtain the solution to the problem of the skin effect in a metal with specular-diffusion boundary conditions for arbitrary values of the anomaly parameter in the form of the Neumann series. For this purpose, we develop a method based on the idea of representation of not only the boundary condition imposed on the field (as is conventionally done), but also the boundary condition imposed on the distribution function, in the form of a source. The specular reflectance is an arbitrary function of the angle of incidence of electrons on the metal surface.  相似文献   

20.
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.  相似文献   

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