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This paper provides the foundations of an original theory of quasi-reproducible experiments (QRE) based on the testable hypothesis that there exists an essential correlation (memory) between successive measurements. Based on this hypothesis, which the authors define for brevity as the verified partial correlation principle (VPCP), it can be proved that there exists a universal fitting function (UFF) for quasi-periodic (QP) and quasi-reproducible (QR) measurements. In other words, there is some common platform or "bridge" on which, figuratively speaking, a true theory (claiming to describe data from first principles or verifiable models) and an experiment offering this theory for verification measured data, maximally "cleaned" from the influence of uncontrollable factors and apparatus/soft wire function, meet. The proposed theory has been tested on eddy covariance ecological data, specifically measuring only the concentration of , and water vapors of in the local atmosphere where the corresponding detectors for measuring of the desired gases content are located. For these tested eddy covariance data associated with the presence of two gases , and vapors in atmosphere there is no simple hypothesis containing a minimal number of the fitting parameters, and, therefore, the fitting function that follows from this theory can serve as the only and reliable quantitative description of this kind of data belonging to the tested complex system. Applications of this theory to practical applications, the place of this theory among other alternative approaches, (especially touching the professional interests of ecologists) and its further development are discussed at the end of this paper. [ABSTRACT FROM AUTHOR]

We present the description of a quasi-spherical coordinate system that is introduced in a space of parameters of a multilayer perceptron with ReLU and Leaky ReLU activation functions. In this instance, a regression loss function that is given in these coordinates becomes the sum of functions that depend on a set of functions defined on a sphere and a quasi-radial coordinate. Conditions for a concentration of measure are satisfied for the functions on the sphere. As a number of parameters tends to infinity, these criteria cause the loss function to concentrate toward a quasi-radially symmetric function. [ABSTRACT FROM AUTHOR]

West Siberian crude oils from the Samotlorskoye oil field, diesel fractions, and I-20A industrial oil were desulfurized with metal chlorides (ZnCl2, FeCl3, and AlCl3) and with a reagent complex (formulation) consisting of 70 wt % AlCl3, 25 wt % oxygenated diesel fuel, and 5 wt % NaOH. Purification of a mixed diesel fraction with an AlCl3 + NaOH (at a weight ratio of 10 : 1) formulation reduced the sulfur content in the diesel mixture from 0.82 to 0.146%. When purifying I-20A with a formulation at a weight ratio of 1 : 1, the sulfur content in the oil decreased from 0.2 to 0.03%. When the West Siberian crude oil (in which organosulfur compounds had been pre-oxygenated by an ozone–oxygen mixture into sulfoxides and sulfones) was purified with a formulation at a weight ratio of 20 : 1, the sulfur content was reduced from 1.8 to 0.5 wt %. The spent formulation was disposed of by introduction into bitumen. [ABSTRACT FROM AUTHOR]

An experimental method is presented for determining the minimum time interval for filling a storage tank with working fluid during reproduction of the units of mass and volume of fluid in a flow and the mass and volume flow rates of the liquid by a calibration unit with a weighing device. Experiments are done over a wide range of mass flow rates 11.10–83.26 kg/s (40–300 t/h) with repeated static weighing of the working fluid. The flow switch is made with a fixed geometry of the flow-through part of the nozzle cutoff, which is typical of a large number of calibration units with weighing devices in use in our country. Plots of the experimental data on the mass flow rate as a function of the time to fill the storage tank are the basis for optimizing the process of reproducing the units of mass and volume of fluid in a flow and the mass and volume flow rates of a liquid by calibration units with weighing devices. These graphs yield recommendations for a justified choice of minimum time interval for filling the storage tank with working fluid within the range of mass flow rate being studied. The optimization has been tested and can be extended to calibration units with weighing devices from various manufacturers with individual designs and operating parameters. [ABSTRACT FROM AUTHOR]

Polyaniline (PANI) represents itself a class of polymers having ionic and electronic conductivities. The polymer has wide application as chemical modifier of electrodes for voltammetry. Electrochemical polymerization of aniline includes in itself some oxidation/reduction stages of electroactive groups. In the result of this process, polyaniline structures of different contents are formed. The qualitative and quantitative contents of polymer film and its area and morphology during the polymerization process play an important role in electroconductivity and response of the final synthesis product on analyte. We demonstrate a possibility of quantitative description of the polyaniline electrochemical polymerization process in the frame of percolation model covering wide temporal range (100–500 reduction/oxidation cycles). We can evaluate the basic parameters (number of percolation channels and fractal dimensions with respect to the applied potential) characterizing the quality of electrode polymer cover. The microphotos obtained with the help of the high-resolution scanning electron microscope support the obtained results independently. [ABSTRACT FROM AUTHOR]

Abstract: The tribotechnical characteristics of grease oxidized with ozone and modified with a carbon framework (CF) are studied. It is shown that, starting from the temperature of 150°C and up to 600°C, the ozone oxidation of compressor oil KS-19 (grease based) and the active components of a CF used as an additive have a favorable effect on the characteristics of the adhesive interaction under friction due to the low level of plasticity of the frictional contact. [ABSTRACT FROM AUTHOR]

Lithium batteries are currently used as the main energy storage for electronic devices. Progress in the field of portable electronic devices is significantly determined by the improvement of their weight/dimensional characteristics and specific capacity. In addition to the high reliability required of lithium batteries, in some critical applications proper diagnostics are required. Corresponding techniques allow prediction and prevention of operation interruption and avoidance of expensive battery replacement, and also provide additional benefits. Many effective diagnostic methods have been suggested; however, most of them require expensive experimental equipment, as well as interruption or strong perturbation of the operating mode. In the framework of this investigation, a simple diagnostic method based on analysis of transient processes is proposed. The transient response is considered as a reaction to an applied load variation that typically corresponds to normal operating conditions for most real applications. The transient response contains the same information as the impedance characteristic for the system operating in linear mode. Taking into account the large number of publications describing the impedance response associated with diagnostic methods, it can be assumed that the transient response contains a sufficient amount of information for creation of effective diagnostic systems. The proposed experimental installation is based on a controlled load, providing current variation, measuring equipment, and data processing electronics. It is proposed to use the second exponent parameters U2 and β to estimate the state of charge for secondary lithium batteries. The proposed method improves the accuracy and reliability of a set of quantitative parameters associated with electrochemical energy sources. [ABSTRACT FROM AUTHOR]

Antiwear and extreme pressure properties of N-substituted 1,3,5-dithiazinane and 1,5,3-dithiazepanes obtained via the cyclothiomethylation of amines (monoethanolamine, propylamine) with formaldehyde and SH acids (HS, 1,2-ethanedithiol), taken in an amount of 3 wt %, in mineral oils have been studied. [ABSTRACT FROM AUTHOR]

By introducing active additives, a carbon framework may be created within plastic lubricant based on cylinder oil. The influence of such additives on the lubricant properties is investigated, at different temperatures. [ABSTRACT FROM AUTHOR]

Parameters are proposed that characterize the form of individual signals of a speech file, such as the position of quantiles in a selected fragment and the parameters of parabolas that approximate the area under a curve. It is shown that the distribution of these parameters can be used for automatic discrimination of files containing speech in Tatar and Russian languages. [ABSTRACT FROM AUTHOR]

Considered is the existence of an alternative to the speeding-up climate warming predicted due to anthropogenic increase in the concentration of greenhouse gases in the atmosphere. The series of observed and simulated average global air temperature are compared using wavelets. It is revealed that the scenarios of the climate change for the next decades cannot be worked out based on the modern climate models. Proposed is the scenario based on the real peculiarities of global temperature variations. According to this scenario, not only the temperature stabilization that has lasted for 15 years will be kept but also the certain cooling is possible. [ABSTRACT FROM AUTHOR]

This paper illustrates the efficiency and simplicity of a new technique which is determined in this paper as NIMRAD (the non-invasive methods of the reduced analysis of data) for describing information extracted from biological signals. As a specific example, we consider the respiratory data. The NIMRAD can be applied for quantitative description of data recorded for complex systems in cases where the adequate model is absent and the treatment procedure should not contain any uncontrollable error. The theoretical developments are applied to signals measured from the respiratory system by means of the forced oscillation technique based on non-invasive lung function test. In order to verify the feasibility of the proposed algorithm for developing new diagnosis tools, we apply NIMRAD on two different respiratory data sets, namely from a healthy subject and from a patient diagnosed with asthma. The results are promising and suggest that NIMRAD could be further tailored and used for specific clinical applications. [ABSTRACT FROM AUTHOR]

The authors obtain the closed self-consistent system of equations for calculation of the desired thermodynamic values of the Ising magnet with arbitrary spin and in presence of the single-ion anisotropy in the frame of the original static fluctuation approach (SFA). The essence of the SFA is based on accurate calculations of fluctuations of a molecular field. As an example the complete analysis of the critical behavior of the Ising magnet with spin S = 1 (Blume-Capiel model) is shown. The expressions for the phase transitions lines of the first and the second order are found. In addition, the coordinates of the tricritical point for some types of cubic lattices are found also. [ABSTRACT FROM AUTHOR]

The article focuses on the possibility of the formation of magnetic linear chains of ortho-water molecules among supramolecular water complexes as well as their magnetic and thermodynamic properties. It cites the different scenarios on the formation of linear magnetic chains, which include the acquisition of a nonzero magnetic moment by the ortho-water molecules at the end of linear nanoassociates. It adds that the resulting spin complexes adds stability to nanoassocciate in an aqeous solution.

Based on a self-similar spatial-temporal structure of the relaxation process, we construct a microscopic model for a non-Debye (nonexponential) dielectric relaxation in complex systems. In this model, we derive the Cole-Cole expression for the complex dielectric permittivity and show that the exponent α involved in that expression is equal to the fractal dimension of the spatial-temporal self-similar ensemble characterizing the structure of the medium and the relaxation process occurring in it. We find a relation between the macroscopic relaxation time and the micro- and mesoparameters of the system. We obtain a generalized Cole-Cole expression for the complex dielectric permittivity involving log-periodic corrections that occur because of a discrete scaling invariance of the fractal structure generating the relaxation process on the mesoscopic scale. The found expression for the dielectric permittivity can be used to interpret dielectric spectra in disordered dielectrics. [ABSTRACT FROM AUTHOR]

We suggest a new method of calculation of the equilibrium correlation functions of an arbitrary order for the interacting Fermi-gas model in the framework of the static fluctuation approximation method. This method based only on a single and controllable approximation allows obtaining the so-called far-distance equations. These equations connecting the quantum states of a Fermi particle with variables of the local field operator contain all necessary information related to the calculation of the desired correlation functions and basic thermodynamic parameters of the many-body system. The basic expressions for the mean energy and heat capacity for the electron gas at low temperatures in the high-density limit were obtained. All expressions are given in the units of r, where r determines the ratio of a mean distance between electrons to the Bohr radius a. In these expressions, we calculate terms of the respective order r and r. It is also shown that the static fluctuation approximation allows finding the terms related to higher orders of the decomposition with respect to the parameter r. [ABSTRACT FROM AUTHOR]

We obtain an expression for the NMR line at low temperatures for a system of nuclear spins described by a Hamiltonian with equal spin-spin coupling constants. We show that in the case of 'easy axis' anisotropy, the line has a logarithmic low-frequency singularity and an exponentially decreasing high-frequency asymptotic behavior at the temperature of an anomalous peak of heat capacity. In the case of 'easy plane' anisotropy, the line has the traditional Gaussian form. We discuss the possibility of using NMR data to discover specific thermodynamic and magnetic properties of the considered model system. [ABSTRACT FROM AUTHOR]

method of calculating the equilibrium correlation functions of any arbitrary order for the Baldwin- Kolesnikov-Shelah (BKSh) model is suggested based on the static fluctuational approach. The method based on only one controllable approach allows the so-called equations of long-range coupling to be obtained which contain all information on the sought-after equilibrium correlation functions within the scope of the BKSh model. Calculations of the sought-after equilibrium correlation functions allow one to go beyond the scope of the conventional molecular field approach and to take into account the effect of field fluctuations on the gap behavior and the heat capacity to the left and right of the critical point. For the simplest case disregarding a dependence of the potential on the wave vector, temperature dependences of the energy gap and heat capacity with allowance for the fluctuations are presented. It is demonstrated that in this case, the fluctuations are small for three-dimensional systems, but sharply increase with decreasing dimensionality of the system. [ABSTRACT FROM AUTHOR]

simple model is proposed for describing magnetic properties of magnetoactive nanoclusters, which permits exact analytic solution. Exact expressions are obtained for thermodynamic characteristics of the model, which hold in the entire range of temperatures, magnetic fields, and interaction parameters. It is found that in the case of easy-axis anisotropy, the field dependence of magnetization of a nanocluster consisting of N particles with a spin of 1/2 has [ N/2] fractional plateaus ([...] is the integer part) corresponding to polarized phases with ruptures singlet pairs. A nonmonotonic behavior observed for the magnetic susceptibility of an easy-plane cluster is typical of gap magnets. The spin gap between the ground state and excited states is proportional to the anisotropy parameter. [ABSTRACT FROM AUTHOR]

In this paper for a given example we proved that the Riemann-Liouville fractional integral term appears naturally and relates the external force with acceleration within the fractional Newtonian equation. The consideration of some self-similar process that leads to the fractional integral as well as some possible generalizations of the proposed model was discussed. [ABSTRACT FROM AUTHOR]

It is possible to find a quantitative universal label (QUL) that can express quantitatively any random sequence in terms of a finite set of quantitative parameters. This label is associated with nine parameters of the generalized Gaussian distribution (GGD), describing all possible correlations (expressed in terms of symmetric products) for all amplitudes { y j} belonging to a random sequence considered. This noise label allows one to compare any randomness with another one and to calibrate these fitting parameters with respect to a possible external factor in the signature (character) space. It opens new resource in signal/noise data treatment and makes it possible to discover completely new relationships that might be hidden in random sequences. This label reflects the distribution of correlations between k stable points existing in the initial random sequence having N initial points ( k ⩽ N). This distribution is free of any model assumption and can be used as a universal quantitative measure characterizing some random sequence. Different examples considered in this paper confirm the effectiveness of the QUL expressed in terms of GGD fitting parameters. [ABSTRACT FROM AUTHOR]

If two random values plotted against each other form a curve close to a straight line, these values are defined as strongly correlated with each other. In this paper, we define these two random values as satisfying the linear principle for strongly correlated variables (LPSCV). For variables of such kind, it is possible to find a new and very general class of distribution functions. One can show that detrended random sequences for relative fluctuations presented in the form of the sequences of ranged amplitudes (SRAs) satisfy the LPSCV. The first results of such kind, based on the analysis of the SRAs, confirm the fact that many random sequences are strongly correlated. For detrended sequences (obtained by numerical differentiation), characterized by a large sampling volume ( N > 1000), the found distribution function, describing the SRA envelopes, can be written as [1] F( t) = a 1 t v 1 + a 2 t v 2. The results obtained in this study open new possibilities for analysis of many complex systems, where the natural relationships are very difficult to find and in cases where they are not known. Examples based on available data confirm this basic statement and show that the envelopes of relative fluctuations presented in the form of SRAs are described by the general distribution function found here. [ABSTRACT FROM AUTHOR]

For the model of equal spin-spin interactions, we obtain exact Heisenberg expressions for the spin operator components and use them to find the relations that hold for spin operators appearing in the thermodynamic mean. We use the obtained exact relations for the means to describe the thermodynamics of the model under consideration. [ABSTRACT FROM AUTHOR]

For the zero solution of the difference equation x(n) = ax(n - m) + bx(n - k) with arbitrary delays k, m, the formulas of the stability domain boundaries were derived. For different k and m, the stability domains were compared in the quadrants of the plane (a, b). [ABSTRACT FROM AUTHOR]

In this work liquid helium-4 is studied for the first time within the framework of the so-called static fluctuation approximation. This is based on the replacement of the square of the local-field operator with its mean value. A closed set of nonlinear integral equations is derived for weakly as well as for strongly interacting systems. This set is solved numerically by an iteration method for a realistic interhelium potential. The thermodynamic properties are then obtained for both the weakly interacting system, liquid 4He in Vycor glass, and the strongly interacting system, liquid 4He. It turns out, however, that the present quadratic-fluctuation approximation is valid in the latter, strongly interacting case only in the low-temperature limit (≤0.15 K). Our results are presented in a set of figures. The role of the interaction is emphasized and the functional dependence of key thermodynamic quantities on the temperature is derived for both weakly and strongly interacting 4He systems. [ABSTRACT FROM AUTHOR]

A possibility to prepare the biofunctional membranes showing the biocatalytic properties and use those in post-treatment of wastewater containing synthetic dyes have been established. Selected Pseudomonas mendocina and Bacillus subtilis cultures were used as biocatalysts for dye destruction. It has been established that cells in spore form are able to survive in N-methylpyrrolidone that allow to use method of polymer solution casting for membrane preparation. The optimal conditions for entrapping of whole cells of microorganisms into the polymer matrix have been determined. Membrane biocatalytic activity has been studied depending on method of casting solution preparation, biocatalyst loading and operating parameters. Dye destruction occurs both in membrane pores and on membrane surface. Membrane obtained provide discolouring of treated solutions (permeate). The dye concentration in retentate depends on the trans-membrane fluxes. The concentration in retentate need not be observed at relatively low fluxes (up to 20 l/m2 h). [ABSTRACT FROM AUTHOR]

Viewed as a prototype for strongly interacting many-body systems, the spin-1/2 n-dimensional Ising model ( n = 1, 2, 3) is studied within the so-called static fluctuation approximation (SFA). The underlying physical picture is that the local field operator σ with quadratic fluctuations is replaced with its mean value [(σ)2 ≃ 〈(σ)2〉]. This means that the true quantum mechanical spectrum of the operator σ is replaced with a distribution; along with the calculation of its mean value, we take into account self-consistently the moments of this distribution. It is shown that this sole approximation is sufficient for deducing the equilibrium correlation functions and the main thermodynamic characteristics of the system. Special new features of this study include an analysis of the two-dimensional model without periodic boundary conditions, and the demonstration that the phase-transition scenario is quite sensitive to the boundary conditions in the two-and three-dimensional cases. In passing, new boundary problems in mathematical physics are emphasized. [ABSTRACT FROM AUTHOR]

Dewaxing of raffinates by the crystallization method is the most expensive process in modern oil unit schemes. To reduce the cost of producing dewaxed oils, studies are constantly being conducted to develop new versions of the process. One of them is selective hydrocracking, or catalytic hydrodewaxing [1]. [ABSTRACT FROM AUTHOR]

In order to describe relaxation processes not obeying an exponential law a model of a self-similar relaxation process is proposed which is described by an equation containing fractional differentiation operators. It turns out that the complex susceptibility corresponding to such a model system has a form which agrees with the known empirical Cowle—Cowle expression. [ABSTRACT FROM AUTHOR]

A new method of identification of the analytical curves describing experimental data is suggested. It is based on the presentation of the wide class of analytical functions in the so-called eigen-coordinates where the function takes the form of sloping lines. The slopes are related to the initial set of fitting parameters and can be found from the linear least square procedure. The method suggested has been checked in detail on the identification of a free induction signal and main statistical distributions which are widely used in physics, technics and applied statistics. The eigen-coordinates for some relaxation functions have been obtained as well. [ABSTRACT FROM AUTHOR]

A relationship is established between Cantor's fractal set (Cantor's bars) and a fractional integral. The fractal dimension of the Cantor set is equal to the fractional exponent of the integral. It follows from analysis of the results that equations in fractional derivatives describe the evolution of physical systems with loss, the fractional exponent of the derivative being a measure of the fraction of the states of the system that are preserved during evolution time t. Such systems can be classified as systems with 'residual' memory, and they occupy an intermediate position between systems with complete memory, on the one hand, and Markov systems, on the other. The use of such equations to describe transport and relaxation processes is discussed. Some generalizations that extent the domain of applicability of the fractional derivative concept are obtained. [ABSTRACT FROM AUTHOR]

A simple method is proposed for estimating approximate integrals of motion (AIM), introduced in [4-6], which is based on a previously proposed technique for calculating CF of a multiparticle problem. This method permits examining a new model in the theory of magnetism and shows that it has an exact asymptotic solution. [ABSTRACT FROM AUTHOR]

A method is proposed for closing the infinite system of equations of the correlation functions that makes it possible to take into account correctly the initial approximation and calculate the approximation to the extent to which it corresponds to the structure of the initial approximation. [ABSTRACT FROM AUTHOR]

Equations for the magnetization in the second order with respect to the interaction, which take account of quadratic fluctuations of the molecular field, are derived. [ABSTRACT FROM AUTHOR]

A fast (express) device for determining the degree of motor oil dilution with a fuel and the engine wear is described. Express (proximate) analysis is performed for a working engine without presampling. [ABSTRACT FROM AUTHOR]

Technology is proposed for production of transformer oil with improved performance characteristics based on a narrow oil cut of medium-sulfur paraffin-base crude by selective treatment with N-methylpyrrolidone and final treatment with an adsorbent in fixed conditions. The oil obtained is distinguished by high stability of the electrical characteristics. [ABSTRACT FROM AUTHOR]

The method of approximate integrals of the motion is used to obtain equations describing the thermodynamics of Bose and Fermi systems with more consistent allowance for interparticle correlations. Under some simplifying assumptions, these equations lead to well-known results of theory. [ABSTRACT FROM AUTHOR]

A new method is proposed for computing the temperature and time correlation functions which permits taking correctly into account the desired order in the interaction. [ABSTRACT FROM AUTHOR]