Assessment of environmental and economic efficiency of iron ore breaking technology using emulsion explosives

Methodology for calculating parameters of drilling and blasting operations for stoping works in mines of Kryvorozhskiy basin and PJSC «Zaporizhskiy iron-ore plant» has been improved with the help of established coefficient of relative capacity for the Ukrainit-PM-2B explosive. A new technology of stoping operations for ore breaking by square-chamber methods at deposit thickness more than 5 m is proposed which assumes usage of emulsion explosives and downward drilling of production hole rings in the direction of underlying drilling horizons. Ecological and economical effectiveness of the proposed ore breaking technology implemented in the extraction chambers was estimated. Regularities of harmful substances hazard index changing were established depending on distance to the emission point when trotyl-contained and emulsion explosives are used. Implementation of the proposed technology allows decreasing prime-cost of 1 ton of ore by 15 % per one extraction unit

Possible effect of extreme solar energetic particle event of 20 January 2005 on polar stratospheric aerosols: direct observational evidence

Energetic cosmic rays are the main source of ionization of the low-middle atmosphere, leading to associated changes in atmospheric properties. Via the hypothetical influence of ionization on aerosol growth and facilitated formation of clouds, this may be an important indirect link relating solar variability to climate. This effect is highly debated, however, since the proposed theoretical mechanisms still remain illusive and qualitative, and observational evidence is inconclusive and controversial. Therefore, important questions regarding the existence and magnitude of the effect, and particularly the fraction of aerosol particles that can form and grow, are still open. Here we present empirical evidence of the possible effect caused by cosmic rays upon polar stratospheric aerosols, based on a case study of an extreme solar energetic particle (SEP) event of 20 January 2005. Using aerosol data obtained over polar regions from different satellites with optical instruments that were operating during January 2005, such as the Stratospheric Aerosol and Gas Experiment III (SAGE III), and Optical Spectrograph and Infrared Imaging System (OSIRIS), we found a significant simultaneous change in aerosol properties in both the Southern and Northern Polar regions in temporal association with the SEP event. We speculate that ionization of the atmosphere, which was abnormally high in the lower stratosphere during the extreme SEP event, might have led to formation of new particles and/or growth of preexisting ultrafine particles in the polar stratospheric region. However, a detailed interpretation of the effect is left for subsequent studies. This is the first time high vertical resolution measurements have been used to discuss possible production of stratospheric aerosols under the influence of cosmic ray induced ionization. The observed effect is marginally detectable for the analyzed severe SEP event and can be undetectable for the majority of weak-moderate events. The present interpretation serves as a conservative upper limit of solar energetic particle effect upon polar stratospheric aerosols

The minimal compound-complex sentence hierarchy

This article deals with the problem of the study of the subsystem of such type of the Multiple Compound-Complex Sentence as a minimal compound-complex sentence. The authors analyze the formal structure of the multiple compoundcomplex sentences and try to build up the structural models hierarchy of Minimal Compound-Complex SentenceyesBelgorod State Universit