Home – Home – Jornals – Humanitarian sciences in Siberia 2007 number

This paper deals with the behavior of fine gold particles (0.25-0.1 mm) and gold dust (<0.1 mm) during the formation of alluvial placers in denudation areas in southern West Siberia. Native gold particles with a low settling velocity, <5-10 cm/s, such as dust (<0.1 mm) and fine flat particles, are transported with a river stream beyond denudation areas. This easily migrating gold participates in the formation of lithochemical flows, which are an important indicator of gold mineralization. It occurs in the upper beds of alluvial section. Heavier fine gold particles are partly retained at the site of river activity, and the rest are partly redeposited in cooler parts of placers, being graded according to their settling velocity, as evidenced from the direct relationship between the flatness and size of gold particles. Fine gold particles do not form large accumulations in alluvial autochthonous placers. The main typomorphic features of fine gold particles and gold dust are their abundance in ore sources, compositional similarity to larger gold fractions, and high migration ability. In contrast to morphological features of gold, these ones remain stable during the river drift.

Geology and mineralogy of the Ulakhan Au-Ag epithermal deposit (northeastern Russia, Magadan Region) are considered. A four-stage scheme of mineral formation sequence is proposed. Concentrations of Au and Ag in minerals of early and late parageneses were determined. It has been established that uytenbogaardtite is associated with native gold and hypergenesis stage minerals - goethite, hydrogoethite, or limonite replacing pyrite. The compositions of uytenbogaardtite (Ag₃AuS₂), acanthite (Ag₂S), and native gold were studied. The composition of the Ulakhan uytenbogaardtite is compared with those of Au and Ag sulfides from other deposits. Thermodynamic calculations in the system H₂O-Fe-Au-Ag-S-C-Na-Cl were carried out, which simulate the interaction of native gold and silver with O₂ and CO₂-saturated surface waters (carbonaceous, sulfide-carbonaceous, and chloride-sodium-carbonaceous) in the presence and absence of acanthite and pyrite at 25

Results of study of different types of inclusions in minerals from mantle xenoliths from the Bele pipe basanites are presented. Two groups of inclusions were recognized in the host minerals according to their genesis. The first group includes single, apparently primary, fluid inclusions. They were discovered only in orthopyroxenes and consist of CO₂ (95 mol.%) and N₂ (5 mol.%). These inclusions had partly leaked. The densities of two least leaked inclusions from different xenoliths are 1.05 and 1.14 g/cm³, and their trapping pressures are estimated at >8.5 and 12 kbar, respectively. The second group includes syngenetic secondary fluid, melt, and crystalline inclusions. In composition the secondary fluid inclusions differ from the primary ones in higher concentrations of N₂ (up to 7 mol.%). Their maximum density is 0.57 g/cm³, which corresponds to 2.4-2.6 kbar and 1100-1200

The Upper Jurassic basalts (150-160 Ma) described as the Ichetui Formation over the territory of the Tugnui, Margintui, and Maly Khamar-Daban volcanic structures have been studied paleomagnetically. It is shown that natural remanent magnetization still contains a component which may reflect the geomagnetic field direction at the beginning of the Late Jurassic. This is supported by reversal and conglomerate tests. Calculation of mean paleopole gives: Plat = 63.6

A pebble of anthraxolite found in the basin of the Kendei River, a tributary of the Lena River, was examined under polarization metallographic and electron microscopes to get an insight into their structure and ontogeny. A polished section of the mineral demonstrates evident anisotropy in polarized reflected light and finely sculptured microrelief of growth and induction surfaces of spherulites on the fracture (fractograms). The morphogenetic inspection and study of ontogenetic signs of origination, growth, phase transformations, and other changes of anthraxolite revealed a growth mechanism typical of spherulitic dendrites owing to low-angle splitting of radial subindividuals. Layered gravity structures (`mineralogical levels') have been found in crystallization voids. They are composed of an ordered even-grained aggregate of spherical crystals of anthraxolite with the tactoid texture of precious opal. The tactoid mineralogical levels of anthraxolite are characterized by the block structure of microspherulite aggregates, signs of deformation, twinning and geometrical selection of blocks, and elements of recrystallization. Growth-oriented zones of regular nets with endotaxial inclusions of graphite inside the cells have been observed on induction surfaces in spherulitic dendrites. Their appearance is considered an indicator of phase transformations. Supramolecular structures and their effect on the morphology of anthraxolite are discussed in short.

A resistivity model of the southern Urals to depths of 120 km was obtained by numerical simulation of natural- and controlled-source EM soundings at 160 kHz to 4 · 10^-4 Hz. The structure of crust and upper mantle was imaged along a transect running ~800 km across the East European Platform, the Ural foredeep, and the Ural mountains. The new data on geology and tectonics of the southern Urals enlarge the knowledge gained through URSEIS-95 reflection profiling along one of best representative cross-orogen profiles. We discovered a large conductor traceable to depths at least 100-120 km at the junction between the East European Platform and the Ural foredeep. It indicates that the Ural foredeep originated in a weak tectonic zone at the platform edge. The Ural orogen is imaged as a nearly bivergent structure to depths of 70-80 km producing a mosaic pattern of conductors rooted deep beneath the Magnitogorsk greenstone province and the granitic belt of the central East Ural uplift where it is 150 km wide at a depth of ~120 km. We interpret the discovered deep roots in the context of the geological history of the Urals.

We derived equations of effective conductivity coefficients to estimate mean current density and its variance in resistivity logging problems for isotropic multi-scale porous media with lognormal conductivity distribution. The equations have quite a simple form if the medium parameters satisfy refined Kolmogorov's similarity hypothesis. The results of the refined perturbation theory obtained using subgrid modeling are compared with the results of numerical simulation and the conventional perturbation theory.

The paper reports physical, physicochemical, and mineralogical-petrographic studies of serpentinite samples from the Bazhenovo deposit of chrysotile asbestos. The samples differ in mineralogy, physical and physicochemical parameters, and in quality (fiber tenacity) of the hosted chrysotile asbestos. The experiments allowed estimating the temperature dependence of electrical resistance of serpentinites in a range of 20 to 800

A microwave detector including a single-element infrared (IR) photodiode mounted in a cooled Dewar and a preamplifier is developed. An IR photodiode of the n⁺

A technology of growing variband P

Problems of using charge-injected devices in hybrid infrared focal plane arrays are considered.

Results of experimental investigation of thermography systems based on InAs CID elements of line and matrix hybrid modules (a thermal imager and IR microscope) are presented. Owing to a high time stability, in the short-wave IR range, the implemented thermography systems have a temperature resolution of ~(4

A design and parameters of the IR spectrograph based on an MS2004I monochromator-spectrograph and a hybrid microcircuit of a one-dimensional 1

A time delay-integration (TDI) readout circuit for implementing IR FPA with an arbitrary number of TDI stages is considered.

Principles of operation of large-scale photodetector arrays for image visualization in a submillimeter spectral range are considered. Parameters of a thermal picture produced on an intermediate screen by a submillimeter component of radiation of an object with a temperature of about 300 K are estimated. Photodetector array parameters required for registration of the intermediate screen radiation are analyzed. The possibility of creating large-scale photodetector arrays on PbSnTe : In films for imaging objects with a room temperature without additional submillimeter illumination is shown.

Principles of designing and functioning the 320

Admittance of MOS structures based on Hg₁

Results of measuring the current-voltage characteristics of diodes with a control electrode are presented. The diodes are based on graded energy-gap Cd_0.22Hg_0.78Te (MCT) layers grown by molecular beam epitaxy (MBE) on a semi-insulating GaAs substrate. The diodes are designed for the IR radiation photodetectors with the cutoff wavelength l_c = 10 mm. It is shown that the surface currents contribute substantially to the reverse currents of MBE MCT photodiodes during enrichment and depletion. A critical built-in charge density value for which the surface leakage level is under 20% of bulk current is obtained.

A simple method is proposed for determining the critical pressure that does not destroy Cd_xHg₁

HgTe/Cd_0.735Hg_0.265 nanostructures with HgTe quantum wells 16.2 and 21.0 nm thick are grown without additional doping on (013)CdTe/ZnTe/GaAs substrates by the method of molecular beam epitaxy. The compositions and thicknesses of the wide-gap layer and quantum well in the course of growth are performed by means of ellipsometry. The accuracy is Dx ≈

An infrared 320

Methods for simultaneous refining the outer orientation parameters of satellite cameras in synchronized shooting from two spacecrafts moving in the same orbit are proposed and investigated. The methods are based on taking into account perspective relations between corresponding coordinates of projections of region elements in a synchronized series of stereograms under assumption that the common aiming point of the cameras does not change during shooting. A method for space shooting simulation is described and used for investigating the dependences of the errors of estimating the orientation angles of the cameras on the number of stereograms and the noise level in projective coordinates of region element images

It is shown that for the p-order autoregressive process, in the case of using a prediction optimized for minimum root-mean-square error, and the known autoregressive coefficients, the predictability time can exceed the correlation time by a factor of p for the best combination of autoregressive coefficients.

The problem of processing measurements containing dynamic observation interferences is solved. The obtained method is invariant to piecewise continuous interferences of deterministic structures with unknown parameters. The method does not require extending the state space and speeds up solving the estimation problem.

Selective effects of the centroid transformation method for structural analysis of monochrome graphic images are investigated. The principle of centroid transformation with the use of functionals of the type of moments for constructing space-structure parameters is described. Two processing schemes are considered: a centroid value accumulation scheme and a cluster scheme. It is shown that when the image is affected by noise, even a high-intensity noise, the scheme of detecting structure elements and borders via clustering the values of parameters is quite efficient. Analytical expressions defining the coordinates of centers and the sizes of clusters, and also the values of rms deviations of the parameter values as a function of rms deviations of the value of uncorrelated additive image noise are found.

Nonparametric pattern recognition algorithms based on a randomized optimization approach are proposed. The idea of the approach is to validate the random character of fuzziness factors of kernel functions and choose parameters of their distribution law by optimizing nonparametric decision rules. Properties of the developed qualifiers are investigated. Results of their comparing with conventional nonparametric pattern recognition algorithms are analyzed.

Problems of synthesizing neural-network models under incomplete experimental data are described. The accuracy of the models is heavily dependent on their complexity. The proposed method allows self-organizing neural-network models of near-optimal complexity. Examples of synthesizing models of flame interferometry and growth of industrial production are presented.

Angular selectivity of volume phase transmission gratings formed in a liquid crystal composite for s- and p-polarized light is investigated in the absence of external electric field.

Numerical modeling is performed in order to extract the fluence and energy for the case of dielectric SiO₂ layers implanted by Si⁺ ions from spectroscopic ellipsometry measurements. To this end, one-, two-, and three-layer models are tested. It is found that a two- or three-layer model is sufficient for determining the implantation parameters and dielectric layer thickness with acceptable accuracy. Further complication of the model does not improve the accuracy, but greatly complicates the search procedure for minimization of objective function.

Single-frequency traveling-wave Nd:YAG and Yb:YAG lasers combining the functions of intracavity second harmonic generation and birefringent filter on one nonlinear crystal are discussed. The lasers were developed for spectroscopy and metrology applications. Output characteristics and spectral tuning ranges of the lasers are presented.

A new technique of low-coherent interferometry is discussed. In the method, the optical field reflected from the layered medium is directed into a longitudinal share scanning interferometer for autocorrelation analysis. The object under analysis is outside the interferometer and the reference beam is not used. Theory, results of numerical simulation, and experimental data are presented.

The possibility of visualizing the fine structure of optical inhomogeneities in gas and condensed fluids by Hilbert optics methods is discussed. Application of optical Hilbert filtering for investigating shock waves and dynamic perturbations induced by the waves in gas is described.

A method for detecting surface defects is discussed. The method is based on analyzing the light scattering function with reference to the problem concerned with automatic control of a fuel cladding surface.

Software and hardware for laser writing systems are presented. A method of multipage recording with allowance for object motion, aimed at dynamic formation of images on cylindrical surfaces, is proposed. Tools for creating protective laser marking with the use of the multilevel regime of laser writing are implemented.

This article of the astroarchaeological orientation is devoted to deciphering of the image of mammoth and symbolic text impressed upon the plate of mammoth tusk (approximately 24 000 years ago). The author succeeded in re-creating of the lost part of the symbolic records on the right end of the plate, in reconstructing of the system of lunar and solar time notation, as well as in determining of the New Year

The article is devoted to the cult complex of the Neolithic Epoch at the archaeological Xishuipo Site in North China (the Honan Province). This cult complex consists of several solitary and collective burials executed according to the rite of the primary and secondary burials. The figural layings of river-molluscs shells representing depictions of mythical and real animals (tiger, dragon, fish, etc.) are the unique part of the funeral rite. These layings mark the sacral space in accordance with principles of natural philosophy of East Asia. The author

The author continues the analysis of A.P. Perevalova

In the article are presented the basic characteristics of the Siberian memoirs written in 1851

A technique is developed for optimal control of dynamic processes in boiler aggregate based on the nonlinear mathematical programming and its program implementation is conducted. A comparison is presented for the regulation of dynamic process of the loading variation of the TP-81 boiler on the basis of the given technique and while using the conventional proportional-integral-differential regulators.

4 August, 2007  is the 60th anniversary of Prof. Amir A. Gubaidullin, the well-known scientist, Doctor of the Phisical and Mathematical Sciences. The entire life of A.A. Gubaidullin shows his aspiration for cognition, devotion to science, remarkable talent, and  honesty.