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1.
The artificial ionospheric turbulence occurs in the ionosphere illuminated by high power HF radio waves. There are a lot of irregularities stretched along the geomagnetic field in this region. The investigation of the artificially disturbed ionospheric region is based on the reception of back scattered signals (BSS) which permits the basic parameters of this region to be estimated and its inhomogeneous structure to be described.Experiments were carried out using ‘Sura’ heating facility in the frequency range of ? = 4.7–9 MHz (ordinary mode) with the effective radiated power Peff = 50–70 MW beamed vertically upwards. The most important dynamic and statistical BSS characteristics (the built-up time, the relaxation and autocorrelation times, the BSS amplitude spatial correlation function and power spectra) were measured using probe waves in the frequency range of that made it possible to obtain the basic parameters of the artificial irregularities. The model representation of a disturbed region in a form of a periodic structure gives a possibity to evaluate the scale of the structure, the whole size of the disturbance and its power and to calculate the main BSS characteristics.  相似文献   
2.
The mineral industry is leading towards a technology driven optimization process. Drilling and blasting are such unit operations in a mine, which can alter the balance sheet of the mine if not planned properly. The development, improvement and utilization of innovative technologies in terms of blast monitoring instruments and explosives technology are important for cost effectiveness and safety of mineral industries.

The ever-growing demand for minerals has compelled the industry to adopt large opencast projects using heavy equipment. This has necessitated use of a few hundred tonnes of explosives in each blast. The bulk delivered fourth generation explosives have solved the problem of explosive loading to a large extent as it provides improved safety in manufacturing, transportation and handling. Bulk delivered emulsion is non-explosive until gasification is complete and a large quantity of explosive can be transported and loaded into blast holes efficiently and with safety. The priming of bulk delivered explosives in Indian mines uses the conventional PETN/TNT-based boosters. The conventional booster possesses safety problems in terms of handling and use, so Indian Explosives Ltd has developed an emulsion-based booster (Powergel Boost).

This paper explores the potential of an emulsion-based booster used as a primer to initiate bulk delivered emulsion explosives used in mines. An attempt has been made at a comparative study between the conventional booster and the emulsion-based booster in terms of the initiation process developed and their capability of developing and maintaining a stable detonation process in the column explosives. The study has been conducted using a continuous velocity of detonation (VOD) measuring instrument, the VODMate two channel system manufactured by Instantel Inc. of Canada. During this study three blasts were monitored. In each blast two holes were selected for study, the first hole was initiated using a conventional booster while the other one used an emulsion-based booster. The findings of the study advocates that the emulsion-based booster is capable of the efficient priming of bulk delivered column explosive with a stable detonation process in the column.  相似文献   
3.
The weathering crust of the Beden ultrabasite massif (the basin of Big Laba River) is identified and studied. Anomalously high contents of noble metals (Au, Pt, Pd) are revealed in the basal horizon of the Jurassic part of the weathering crust. For this reason we suspect an existence of a belt of noble metal miner-alization in the Paleozoic ultrabasites in the Peredovoi Range of the Northern Caucasus.  相似文献   
4.
Features of marine regression along the Indian Coast during the Quaternary have been studied using the Landsat Imagery for the possible causes and mechanisms of their formation. The occurrence of these features, specially cheniers, is very prominent along the Krishna — Godavari coast. Variations in the inland distances of the cheniers at different locations along the coast indicate differential regressions of the coast at different places. Progradation of the coast and local uplift are identified as the main factors for the same. The topography of the shelf before the regression has played an important role in the development of the regression surfaces of varying widths and the spatial arrangement of the regression features. Morphostructural factors have hindered the formation of deltas along the western coast and also the formation of regression features. Some of the gently sloping coasts without the regression features are the active zones of sediment erosion. The study points to the possibility that some of the coasts/deltas are tectonically active zones. The Krishna Godavari delta is undergoing uplift and the coasts/deltas of the Sundarbans, Mahanadi, Kerala and Saurasthtra are undergoing down-warping. This fact needs to be confirmed using data form deep drillings, geophysical tests and other sources. The confirmation of these phenomena will have a significant effect on the depth of sediment deposition, their maturity and finally on the formation, occurrence and migration of hydrocarbons.  相似文献   
5.
6.
A new method of determining the age of native platinum based on alpha-radioactivity of one of its natural isotopes 190Pt is proposed. Due to a special form of occurrence of radiogenic helium in the crystal lattice of native metals as a helium cluster-bubbles, the stability of 190Pt-4He of the isotope system is extremely high in the natural environment. To check the efficiency of the proposed 190Pt-4He method of isotope geochronology, six independent mineral aggregates of native platinum from chromite-bearing dunites of the southern part of platinum-bearing zonal Galmoenan dunite-cllinopyroxenite-gabbro plutonic complex (Koryak-Kamchatka belt, Russia) were analyzed. The age calculated by the tangent of the 190Pt-4He isochrone slope angle equals 69.5 ± 4.9 mln years. The obtained age value coincides with the results of isotope datings, which were made previously by different methods of isotope geochronology.  相似文献   
7.
The Late Cretaceous ükapili Granitoid including mafic microgranular enclaves intruded into metapelitic and metabasic rocks, and overlain unconformably by Neogene ignimbrites in the Ni de area of Turkey. It is mostly granite and minor granodiorite in composition, whereas its enclaves are dominantly gabbro with a few diorites in composition. The ükapili Granitoid is composed mainly of quartz, K-feldspar, plagioclase, biotite, muscovite and minor amphibole while its enclaves contain mostly plagioclase, amphibole, minor pyroxene and biotite. The ükapili Granitoid has calcalkaline and peraluminous (A/CNK= 1.0-1.3) geochemical characteristics. It is characterized by high LILE/HFSE and LREE/HREE ratios ((La/Lu) N = 3-33), and has negative Ba, Ta, Nb and Eu anomalies, resembling those of collision granitoids. The ükapili Granitoid has relatively high 87Sr/86Sr (i) ratios (0.711189-0.716061) and low εNd (t) values (-5.13 to -7.13), confirming crustal melting. In contrast, the enclaves are tholeiitic and metaluminous, and slightly enriched in LILEs (K, Rb) and Th, and have negative Ta, Nb and Ti anomalies; propose that they were derived from a subduction-modified mantle source. Based on mineral and whole rock chemistry data, the ükapili granitoid is H-(hybrid) type, post-collision granitoid developed by mixing/mingling processes between crustal melts and mantle-derived mafic magmas.  相似文献   
8.
9.
This paper further develops the ideas of V. B. Sochava’s Siberian school of thematic mapping concerning an integral approach in generating synthesis and assessment maps of the habitat on objective grounds confirmed by quantitative calculations. Maps of the natural environment display the invariant structure of the sites of a territory and their variable states. Integral indicators of the state of environment combine differentquality spatial information on the geographical location of the sites having regard to the scientific principles of qualimetry. An unbiased calculation of integral indicators is ensured through the use of the method of principal component analysis. The first principal component characterizes a maximum of variation in information on the geosystem, and the second component refers to a stable environment background. Their difference for each location corresponds to the potential of geosystem variability. The resulting integral indicators are displayed on assessment cartograms. The entire array of independent principal components is used for a classification of geosystems using the method of k-means clustering to create the typological map of the territory. Calculations are based on data for forest management of the Slyudyanka Leskhoz within the boundaries of the Slyudyanka municipal district of Irkutsk oblast. The territorial norm of the geographical environment corresponds to geosystems of the mountain-taiga belt of the Siberian stone pine and larch taiga on different-aspect slopes. Negative deviations from the norm are induced by high-mountain goletz and subgoletz geosystems on steep slopes, and positive deviations correspond to flat interfluves and gentle slopes.  相似文献   
10.
A new phenomenon was found at the polar edge of the auroral oval in the postmidnight-morning sectors: field-aligned (FA) high-energy upward electron beams in the energy range 20–40 keV at altitudes about 3 RE, accompanied by bidirectional electron FA beams of keV energy. The beam intensity often reaches more than 0.5 · 103 electrons/s · sr · keV · cm2, and the beams are observed for a relatively long time (3 102–103 s), when the satellite at the apogee moves slowly in the ILAT-MLT frame. A qualitative scenario of the acceleration mechanism is proposed, according to which the satellite is within a region of bidirectional acceleration where a stochastic FA acceleration is accomplished by waves with fluctuating FA electric field components in both directions.  相似文献   
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