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1.
We present a theoretical formalism of correlation phase analysis of laser images of human blood plasma with spatial-frequency selection of manifestations of mechanisms of linear and circular birefringence of albumin and globulin polycrystalline networks. Comparative results of the measurement of coordinate distributions of the correlation parameter—the modulus of the degree of local correlation of amplitudes—of laser images of blood plasma taken from patients of three groups—healthy patients (donors), rheumatoid-arthritis patients, and breast-cancer patients—are presented. We investigate values and ranges of change of statistical (the first to fourth statistical moments), correlation (excess of autocorrelation functions), and fractal (slopes of approximating curves and dispersion of extrema of logarithmic dependences of power spectra) parameters of coordinate distributions of the degree of local correlation of amplitudes. Objective criteria for diagnostics of occurrence and differentiation of inflammatory and oncological states are determined.  相似文献   

2.
A new technique of Mueller-matrix mapping of the birefringent structure of biological preparations of human organs tissues is suggested. The algorithms of reconstruction of average values and magnitude of fluctuations of the phase (birefringence) and amplitude (dichroism) of optically anisotropic structure of myocardium and connective tissue component of the vaginal wall histological section are proposed. The magnitudes and ranges of changes in the statistical moments of the 1st-4th order that characterize the distribution of average values and magnitude of fluctuations of birefringence and dichroism of the myocardium and connective tissue of the vaginal tissues histological sections were determined. Joint studies of distributions of the characteristics of phase and amplitude of the anisotropy of myocardium and connective tissue component of the vaginal wall tissues of different states were performed. The cases of various necrotic changes in the myocardium and pathological conditions of the vagina wall (prolapse of the genitals) are examined. Balanced accuracy of the method of Mueller-matrix polarization-phase and diffuse tomography of optically anisotropic polycrystalline networks in the differentiation of necrotic and pathological changes in human organs is determined.  相似文献   

3.
The possibility of the aberration-free reconstruction of a synthesized hologram-Fresnel projector in the case when the angles of incidence of the reconstructing plane wave exceed the angle of incidence of the plane reference wave during hologram synthesis is shown. The character of the dependence of admissible angles of incidence of the reconstructing wave on the parameters of the synthesis of hologram projectors is revealed and described mathematically. The results of an experimental study that confirms the possibility of the aberration-free reconstruction of hologram projectors at angles of incidence of the reconstructing plane wave that exceed the angle of incidence of the reference wave of the plane are presented. The results of the successful implementation of the projection photolithography process using a synthesized relief-phase reflection hologram-Fresnel projector are demonstrated.  相似文献   

4.

The uniformity of composition of rapidly quenched PREP particles of the powder of high temperature Ni-based superalloys and stainless steels is characterized by an important feature—the occurrence of anomalous particles (granules) with a significantly different content, mainly of microalloying interstitial elements, carbon and boron, as well as active carbide- and boride-forming alloying elements. A detailed multi-scale experimental study of the heating zone of the crater of the Ni-based superalloy electrode after its use to obtain rapidly quenched PREP powder was carried out in order to find the nature and mechanisms of the formation of anomalous granules. Direct nuclear physics methods of activation autoradiography on carbon, track autoradiography on boron, metallography, SEM, EDX, OIM were used. In the electrode crater, the heat-affected zone (HAZ) and the partially melted zone (PMZ) were detected. Intense migration of boron to the electrode surface due to the formation of thermal macrocracks was also revealed. The behavior of carbon is determined by the formation of a thin layer of melt on the surface of the crater. The features of the evolution of the terminal solidification region TSR and incipiently melted regions IMR, the main type of heterogeneity of the composition of the dendritic structure of Ni-based superalloys and stainless steels, are revealed. The interrelation of the evolution of these areas is established, which is a consequence of the thermodynamic principle of the reversibility of the processes of solidification and melting, respectively, in the smelting of an ingot electrode and in the process of subsequent atomization. The analysis of the influence of the behavior of boron, carbon, and the characteristics of the crater structure on the nature and mechanism of the formation of anomalous granules using the PREP method for producing rapidly quenched powder of the Ni-based superalloy is performed.

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5.
The effects of the polydispersity of the structure of gold nanoshells and of the limited electron free path in a thin metal layer on the spectra of resonance light scattering of a suspension of two-layer nanoparticles are studied theoretically and experimentally for the first time. It is shown theoretically that both factors lead to a broadening of the plasmon resonance in light scattering and to a change in its magnitude. To experimentally test the calculations, two samples of nanoshells based on gold and silicon dioxide (silica) were synthesized. Nanoshells of sample 1 have a diameter of the core of 90 nm and a broad thickness distribution of shells (with an average value of 30 nm), whereas nanoshells of sample 2 have a diameter of the core of 70 nm and a narrow thickness distribution of shells (with an average value of 12 nm). The core diameter, the shell thickness, and the polydispersity of the structure of nanoparticles are estimated by dynamic light scattering. It is shown that the simulation of the optical properties of nanoparticles with their parameters estimated from the dynamic light scattering data makes it possible to obtain good agreement between experimental and theoretical spectra of light scattering. For nanoshells of sample 1, the inhomogeneous broadening of the scattering spectrum is completely determined by the polydispersity; therefore, the bulk constants of gold can be used in simulation of the spectra of such nanoshells. The main mechanism of the broadening for nanoshells of sample 2 is connected with the limitation of the free path length of electrons, whereas the contribution from the thickness distribution of shells can be neglected.  相似文献   

6.
The report discusses development of the host-based system to carry out timed measurements and data acquisition for the control of pulsed facilities of the accelerator. We consider modes of timing and allocation of operations of channels and the system node. The time of any working cycle of the pulsed facilities, rate of a data flow and an amount of serviced channels are coordinated with operation characteristics of the system node. Estimations of the readout rate of the data and the waiting time demonstrate the system efficiency. The technique has been developed to provide checking of groups of pulse parameters and control the facilities of the linear accelerator of electrons LUE-200 of the neutron source IREN.  相似文献   

7.
For identical particles, consisting of fermions, the upper bound for the number of particles that can occupy a single state is determined. In the macroscopic case, it is proportional to the square root of the number of possible ways of formation of particles of a given composition of all fermions present in the mixture (the normalization constant of the respective density matrix). Particles capable of accumulating in macroscopic quantities in one state can consist only of an even number of fermions of different kinds. In the case of atoms in a trap, this bound can approach arbitrarily close to the total number of atoms. Since the state of the centers of mass of the atoms is described by a symmetric wave function, they, like elementary bosons, can form a condensate, the coherence properties of the components of which are characterized by an antisymmetric wave function of a single atom in relative coordinates.  相似文献   

8.
《Current Applied Physics》2009,9(5):1027-1031
The analysis of fluorescent characteristics and degree of molecular association of three fluorescent nanomarkers (eosin, erythrosin and fluorescein) in solutions of human serum albumin (HSA) at different pHs is made. The common features for all three nanomarkers under influence of bionanomolecules of HSA are the quenching of the fluorescence, the red shift of maximum of fluorescence and the decrease of degree of molecular association for every fixed value of pH. The differences in dependences of fluorescence and degree of molecular association on pH between fluorescein and its halogen – derivatives (eosin and erythrosin) are registered. It is established that the quenching of fluorescence by HSA is of compound statically–dynamical type. The electronegativity of lateral atoms in structural formulas of nanomarkers forms the basis of explanation of all features of experimental data in the system “fluorescent nanomarker – protein – buffer solution”.  相似文献   

9.
Acoustic fields formed during operation of ultrasonic reactors with waveguides of following types: rod-type, cylindrical with rectangular protrusions and tubular were calculated and measured. The influence of distribution of acoustic fields arising from the operation of waveguide systems of three different types on the efficiency of ultrasonic activation of alumosilicic flocculant-coagulant and magnetite intended for water purification was investigated. It was shown that regardless of the equipment used on an industrial scale it is possible to reactivate the alumosilicic flocculant-coagulant even after the shelf life period of it passed, however in case of activation of magnetite the use of a bigger reactor in inefficient.In case of industrial scale processes, the choice of the correct reactor design is of significant importance, since it allows to reduce the required processing time, and, as a result, the energy consumption of the processes. The advantages of tubular waveguide systems include the possibility of processing large volumes of liquid. The high efficiency and uniformity of the excited ultrasonic fields can lead to reduction of operating costs. In case of smaller flows, the waveguide system with rectangular protrusions allowed to obtain better results.Our work illustrates the dependence of the success of a specific method on the choice of the waveguide and the size of the reactor during upscale.  相似文献   

10.
We present the results of quantumchemical investigation of energy transfer in organic molecules and systems and the inferences drawn. The Förster theory has been subjected to a critical analysis in order that the energy transfer could be described in the context of the current theory of nonradiative transitions and the incorrectness of the basic premises of the Förster theory has been demonstrated. A new variant of the mechanism of electronic energy transfer on the basis of the theory of electron transitions and of the quantum mechanics of molecules has been suggested. It is shown that the interaction of the molecules of the donor and acceptor perturbs the electronic states of isolated molecules even before the excitation of the donor molecule. A characteristic feature of the manifestation of intermolecular interaction is the spatial delocalization of the wave functions of the electronic states of interacting molecules, leading to the possibility of occurrence of conventional photophysical processes with participation of the electronic states of various molecules of the bimolecular system. In experimental investigations, the result of the intermolecular nonradiative transition is recorded as evidence of the spatial transfer of the energy of electronic excitation from the donor molecule to the acceptor molecule.  相似文献   

11.
Optical absorption spectra of vapors of metal complexes of octaethylporphyrins known from the literature are analyzed on the basis of notions about sequences as basic elements of the formation of electronic-vibrational bands. According to this analysis, major features of these spectra are explained. These features include considerable half-widths of the electronic-vibrational bands of rarefied vapors, when intermolecular interactions virtually do not affect the broadening; a Lorentzian intensity distribution over the contour of the 0-0 spectral band; long-wavelength shifts of the intensity maxima of bands with increasing temperature; and the origin of a fine structure of the electronic and vibrational spectra at low temperatures. It was concluded that sequential transitions form the basis of the mechanism of formation and broadening of the electronic and vibrational spectra of metal complexes of octaethylporphyrins as representatives of complex biomolecules.  相似文献   

12.
13.
Optical characteristics of polymerization products under variable degrees of neutralization of acrylic acid (AA) and cross-linking agent and at a fixed content of redox components have been studied by IR spectroscopy of frustrated total internal reflection and THz spectroscopy. The results of the analysis show that absorption of IR radiation and dispersion of THz radiation for the samples under study depend on the degree of AA neutralization, which predetermines the mechanism of structure formation of hydrogels, refractive index, and degree of their limited swelling. It is found that the dependences of the refractive index of dry compact hydrogels and the degree of limited swelling of ground polymer samples on the content of neutralizing agent in solutions of the reaction systems have a symbatic character.  相似文献   

14.
The spectra of backscattered energy by dispersed anchovies, which were reported by Holliday (1972), reveal several peaks at frequencies that correspond to theoretically calculated resonance frequencies of year classes of anchovies. Theoretical calculations are based on concurrent measurements of distributions of swim bladder dimensions and a modified form of Minnaert's (1933) equation. Differences between calculated and measured values of the mean lengths of the second-, third-, and fourth-year classes are within experimental uncertainties (+/-8%). The calculated mean lengths of juvenile anchovies are in good agreement with historical measurements of the bounds on this parameter (Butler, 1989). Matching of theoretical calculations and measurements of backscattered energy level versus frequency yields estimates of the total Q of the spectral line, QT, and the relative number density per year class. The resultant estimate of QT of adult anchovies is approximately 4.4. This value of QT is consistent with laboratory measurements of the Q of individual anchovies. Q0 (approximately 7 at 15 m) and measurements of length distributions of year classes and depth distributions. Resultant estimates of relative number densities of year classes were consistent with historical measurements of the relative number densities of year classes of anchovies in the Southern California Bight.  相似文献   

15.
Mathematical modeling of the population dynamics is performed for states of a three-level system (atom) with a V-type configuration transforming a light pulse. It is assumed that the excited eigenstates of the atom are degenerate and coupled by coherent interaction, one of the states being radiating (radiative), while the other state is nonradiating (??dark??). The population dynamics of atomic states is described on the basis of numerical solutions of equations for the matrix elements of the density operator. The dependence of the efficiency of population of the atomic dark state from the values of the parameters of an irradiation pulse and from the ratio of the period of population oscillations of excited atomic states (caused by their coherent interaction) to the lifetime of the atomic radiating state is determined. Typical examples of the time dependence of the population of states of the atom considered are presented for the cases of irradiation by a short (as compared to the lifetime of the radiating state) sinusoidal light pulse and by a long rectangular light pulse with the resonance carrier frequency.  相似文献   

16.
The prospects for using laser beam technologies for disposal of chemical munnition are considered within the framework of works on the destruction of chemical weapons. A single-stage technology of destruction of the subelements of chemical munnition in molten aluminum inside a furnace-armored chamber is described. The rate and the thermochemical processes proceeding during the thermal decomposition of the components of an munnition subelement are analyzed in detail and the yield of secondary harmful substances is calculated. All sources of the secondary harmful substances formed during the thermal treatment of the cases of air chemical munnition are revealed. The chemical composition of the medium inside the heat chamber during treatment of cases of various types of munnition is calculated. The requirements for the purification system of waste gases are determined on the basis of a detailed analysis of all nomenclature of the cases to be treated.  相似文献   

17.
Two pieces of theory which have so far remained unconnected, crystal field theory and the theory of corepresentations of non-unitary groups, are brought together here for the study of the splitting of atomic energy levels in a crystalline field with the symmetry of one of the magnetic (Shubnikov) point groups. The cases of the various possible relative strengths of the crystalline field and of spin-orbit coupling are considered.

Tables are presented which enable the splitting of any atomic energy level to be obtained very easily in a crystalline field with the symmetry of any one of the 58 magnetic point groups. Examples of the use of these tables are given.

A discussion is given of the relevance of Kramers' theorem to the energy levels of electrons in surroundings with the symmetry of any one of the 58 magnetic point groups.  相似文献   

18.
The results of the micromagnetic simulation of forced oscillations of the magnetization in a system of two interacting microstrips located at an angle to each other have been presented. The ferromagnetic resonance spectra and the mode composition of resonant oscillations of the system have been investigated under the conditions of magnetostatic and exchange interactions between the microstrips. It has been shown that the magnetostatic interaction leads to the possibility of the excitation of in-phase and out-of-phase coupled oscillations of the magnetization of the microstrips. In the systems of exchange-coupled microstrips, there are intense resonances due to oscillations of the domain walls. The transformation of the ferromagnetic resonance spectrum and the change in the mode composition of resonant oscillations in different equilibrium configurations of the magnetization of the system have been discussed, as well as the conditions for the excitation of oscillations of different types depending on the direction of the microwave magnetic field.  相似文献   

19.
In the paper, the applicability of decomposition products of internal insulation of high-voltage pulse capacitors is considered (aging is the reason for decomposition products of internal insulation). Decomposition products of internal insulation of high-voltage pulse capacitors can be used to evaluate their quality when in operation and in service. There have been three generations of markers of aging of insulation as in the case with power transformers. The area of applicability of markers of aging of insulation for power transformers has been studied and the area can be extended to high-voltage pulse capacitors. The research reveals that there is a correlation between the components and quantities of markers of aging of the first generation (gaseous decomposition products of insulation) dissolved in insulating liquid and the remaining life of high-voltage pulse capacitors. The application of markers of aging to evaluate the remaining service life of high-voltage pulse capacitor is a promising direction of research, because the design of high-voltage pulse capacitors keeps stability of markers of aging of insulation in high-voltage pulse capacitors. It is necessary to continue gathering statistical data concerning development of markers of aging of the first generation. One should also carry out research aimed at estimation of the remaining life of capacitors using markers of the second and the third generation.  相似文献   

20.
The problem of flow and combustion of turbulent jets of fuel gas in the external medium of an oxidant (air) is solved with regard to the existence of the actual boundary of the turbulent flow region of a jet. Based on the ideas of the friction force of the external flow acting on the boundary of a jet, the entrainment equation for the external medium is derived that closes the system of equations of motion of turbulent jets. The physical meaning of the dissipation rate of the turbulent energy of a jet is interpreted as the work of the friction force. To describe the combustion kinetics, the limit of instantaneous reactions corresponding to the diffusion combustion mode is used. Calculations of the effective reaction rates for reactants and the volumes occupied by them are based on the representation of a turbulent medium as an aggregation of independent turbulent particles—vortices—whose random contacts lead to the mixing and combustion of reacting substances [31]. The concomitant phenomena of flow and combustion are analyzed, including radiation effects. In particular, it is shown that the apparent increase in the combustion temperature with increasing Reynolds number is in fact attributed to the relative decrease of thermal radiation losses. Qualitative agreement is obtained between the results of the theoretical calculations of the length of a combustion torch and experimental data.  相似文献   

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