Ionospheric support of HF radiocommunication using maps of total electron content

The possibility of determining the field of critical frequencies of the ionospheric F2 layer (foF2) using the maps of the total electron content, constructed based on the registration of signals from satellite radio navigation system of the GPS and GLONASS types, is considered. The calculation of foF2 is based on the SPIM (Standard Plasmasphere-Ionosphere Model) model specifying the ionospheric index of solar activity, which is determined at grid points of the map of the total electron content. The proposed method has been verified using the data of the hourly maps of the total electron content in the North American region during September 1–7, 2005. The variations in the critical frequencies for Boulder and Dyess sites, selected from the reconstructed foF2 maps, were compared with the data of the vertical sounding. The average error is ～10% during the entire period of measurements. The conclusion has been drawn that the proposed method can be used as an ionospheric support of HF radiocommunication in the cases when errors of tenths of MHz in foF2 values are permissible.     

Heat flow from the earth’s interior depending on inner parameters variations

The approximate equality of heat flows on the land and the ocean; high heat flow values on the middle oceanic ridges; a relationship of heat flow with age of tectogenesis; the extremely low heat flow values are considered as main evidence for any theoretical explanation. The deviation of surface heat flow from its equilibrium value is considered. Computing analysis of high temperature heat transfer coefficients is given. Some aspects of numerical techniques of the thermal history of the Earth are discussed. The influence of sudden and gradual formation of the Earth Crust on the surface heat flow is considered.     

Laboratory and marine study of photoluminescent sensors of oxygen dissolved in seawater

The laboratory and marine study of photoluminescent sensors developed at the TsAGI has been conducted to create a highly sensitivity gauge of the oxygen dissolved in seawater. The advantages of the photoluminescent gauge over the electrochemical ones are the following: zero sensitivity to electromagnetic fields, the pH of the water, and the hydrogen sulphide and ions of heavy metals in the water; zero oxygen consumption; and no need for the water to be pumped through the device.     

A New Model of a Unique Schlema-Alberoda Five-Element Deposit,Federal Republic of Germany

Geology of Ore Deposits - The paper completes a series of works about the unique Schlema-Alberoda deposit. The data on sources of vein and ore minerals and their relation to the processes of...     

Photoluminescence of silicon‐vacancy defects in nanodiamonds of different chondrites

Photoluminescence spectra show that silicon impurity is present in lattice of some nanodiamond grains (ND) of various chondrites as a silicon‐vacancy (SiV) defect. The relative intensity of the SiV band in the diamond‐rich separates depends on chemical composition of meteorites and on size of ND grains. The strongest signal is found for the size separates enriched in small grains; thus, confirming our earlier conclusion that the SiV defects preferentially reside in the smallest (≤2 nm) grains. The difference in relative intensities of the SiV luminescence in the diamond‐rich separates of individual meteorites are due to variable conditions of thermal metamorphism of their parent bodies and/or uneven sampling of nanodiamond populations. Annealing of separates in air eliminates surface sp²‐carbon; consequently, the SiV luminescence is enhanced. Strong and well‐defined luminescence and absorption of the SiV defect is a promising feature to locate cold (<250 °C) nanodiamonds in space.     

Long-term solar wind variations in the 20th–23rd solar activity cycles according to radio-astronomical data

We analyzed the variations of the interplanetary plasma parameters, obtained from radio astronomical observations of scintillations of cosmic radio sources during four 11-year cycles of solar activity, from 1966 to present. It is shown that the state of the interplanetary plasma permanently changes in conformity with cyclicity in the solar activity. In the studied time period, besides the 11-year variations in the velocity and scintillation index, there is also an increasing linear trend of these variables, which is presumably due to a secular 80–90-year cycle of solar activity. The observed differences between the 11-year variations and trends in the solar wind velocity and interplanetary scintillation index suggest that the 11-year and secular cycles have different origins. It is found that these trends occur in this time period in each link of the Sun-Earth system: in the solar activity indices, in the characteristics of the interplanetary medium, and practically in all characteristics of the geophysical, demographical, medical, and other Earth’s processes. From the entire set of facts we can conclude that most of the analyzed Earth’s processes are dominated not by anthropogenic factors, but by the effects of the secular cyclic processes of the solar activity.     

Pollution Degree of the Don River Water

Water Resources - The formation and distribution of river flow characteristics in the Don basin have been catholically analyzed, depending on the present-day climatic conditions in the central...     

Solar millisecond spikes manifest large-and small-scale inhomogeneities of the coronal plasma

A model for the generation of solar millisecond radio spikes via a maser cyclotron resonance is proposed. The model takes into account the large-scale inhomogeneity of the magnetic field and small-scale inhomogeneities of the coronal plasma. The efficiency of the energy transformation from a electron beam into maser radiation is estimated. Appropriate parameters of the magnetic field inhomogeneity and the plasma turbulence are found.     

桩基建筑物运行中稳定性的治理措施

The vast majority of buildings in Russia have been constructed on pile foundations incorporating a ventilated air space between the structure and ground surface (passive construction method, or Principle I in the Russian Building Code 2.02.04-88). Warming of the frozen soil during the life of the structure is one of the primary factors leading to structural damage. This paper presents a new technique for preventing failure in engineering structures.