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Fine powders of strontium hexaferrite are widely used in powder metallurgy for the production of permanent magnets resistant to atmospheric oxygen and high working temperatures. Obtaining powders with predefined technological characteristics in minimal time and with minimal energy consumption is an actual problem of powder metallurgy. The paper provides the results of experimental studies of technological characteristics of strontium hexaferrite powder (SrFe12O19) during milling in a beater mill. Mechanical milling of coarse strontium hexaferrite was carried out in the mill with the system of rotating beaters for 120 minutes without and with the creation of a pseudo fluidized bed. The fluidization was formed by a perpendicular constant and alternating magnetic field with induction gradients of 150 and 210 mT/m. Average particle size and powder bulk density dependencies from milling time were studied. Experimental data show that milling with the formation of a magneto fluidized bed allows intensifying the process. Beginning from 70 minutes, the dependencies of average particle size and bulk density come to almost asymptotic behavior making further milling rather ineffective. Carried out research allows choosing optimal milling duration for obtaining the required average particle size.

Problem of obtaining fine powders of strontium hexa-ferrite is actual because of its wide applications. The paper provides the results of studies of particle size distribution and structural characteristic changes of strontium hexa-ferrite powder (SrFe12O19) during milling in impact mill and after its consequent annealing. Mechanical processing of coarse particulate system was carried out in the mill for 120 minutes without electromagnetic effect and with creation of magneto fluidized bed, formed by perpendicular constant and alternating magnetic field with induction gradient of 210 mT/m, providing reciprocating motion of particles and aggregates with sizes of 3 – 4 mm. It was shown that milling of coarse strontium hexa-ferrite with average particle size 1558.5 μm and the most possible size 1500 μm in magneto fluidized bed allowed to intensify milling process and to provide a significant increase of powder particle sizes uniformity. It was found out, that milling in magneto fluidized bed leads to a great decrease of coherent scattering regions sizes and an increase of lattice micro-deformations and relative dislocation density. Consequent annealing of the powder for 2 hours at 850°C refined structural characteristics significantly. The carried out research allows to choose the optimal milling duration for solution of practical problems of powder metallurgy.

Дискуссии о том, положительно или отрицательно отражается улучшение экологических показателей компаний на их конкурентоспособности (т.е. на их экономических показателях), ведутся давно: экологи и общественность настаивают на более жестких экологических нормативах, а политики, экономисты и бизнес-сообщество ищут компромисс между издержками на охрану окружающей среды и экономической эффективностью. Понимание этой взаимосвязи является важным для всех полемизирующих сторон, поскольку одновременно преследуются две цели: обеспечение высокого качества окружающей среды, требующее непроизводительных затрат, и получение хороших экономических результатов. Это также важно и для разделения экологических, экономических и политических целей: является ли политика «озеленения» бизнеса, реализуемая во многих странах, реальной борьбой с изменением климата и плохой экологией, или она используется как инструмент мобилизации электората и скрытого протекционизма. Несмотря на большое количество проводимых в данной области исследований, остается открытым вопрос о направленности каузальной связи: приводят ли экологические инвестиции к повышению прибыли или просто выступают индикаторами фирм с высокими финансовыми результатами. В статье проведен сравнительный анализ методов и моделей формирования взаимосвязей между экологическими и экономическими характеристиками фирм в контексте активизации международной экологической повестки как одного из перспективных направлений развития экономического анализа. Авторами показано, что связь между экологическим регулированием и конкурентоспособностью неодинакова и зависит от рыночной структуры отрасли, при этом важными проблемами анализа являются наличие разных подходов к определению понятий «конкурентоспособность», «экономическая эффективность», «экологическая эффективность», «строгость регулирования», а также использование различных показателей для их измерения, сложность подбора косвенных показателей экологического регулирования и конкурентоспособности, а также наличие и качество данных. Изучены возможности и проблемы эмпирического анализа взаимосвязи между экологической и экономической эффективностью по данным крупнейших российских компаний и отечественной статистики., The debate about whether improving companies' environmental performance has a positive or negative impact on their competitiveness (i.e., their economic performance) has been going on for a long time: environmentalists and the public are pushing for stricter environmental regulations, and politicians, economists and the business community are looking for a compromise between environmental costs and economic efficiency. Understanding this relationship is important for all polemicizing parties, as two objectives are pursued simultaneously: ensuring high environmental quality, which is costly, and obtaining good economic results. It is also important for separating environmental, economic and political goals: whether the policy of "greening" business, implemented in many countries, is a real fight against climate change and bad ecology, or is it used as a tool to mobilize electorate and hide protectionism. Despite the large number of studies conducted in this area, the question of the direction of the causal relationship remains: whether environmental investments lead to higher profits or simply act as indicators of firms with high financial results. The article conducts a comparative analysis of methods and models for the formation of interrelations between environmental and economic characteristics of firms in the context of activating the international environmental agenda as one of the promising directions for the development of economic analysis. The authors show that the relationship between environmental regulation and competitiveness is not the same and depends on the market structure of the industry. In addition, the presence of different approaches to the definition of the concepts of "competitiveness", "economic efficiency", "environmental efficiency", "strictness of regulation", as well as the use of various indicators to measure them pose important analysis problems. The complexity of selecting indirect indicators of environmental regulation and competitiveness, as well as the availability and quality of data also play a significant role. The possibilities and problems of empirical analysis of the relationship between environmental and economic efficiency according to the data of the largest Russian companies and domestic statistics are studied.

Article presents an experimental study result of milling coarse strontium hexaferrite in beater mill with formation of magneto fluidized bed and without it. Magneto fluidized bed is formed by mutually perpendicular constant and alternating gradient magnetic fields. We studied the dynamics of particle size distribution from milling time and parameters of magnetic fields. Microstructure dynamics of strontium hexaferrite powder particles milled in various regimes was studied by X-ray diffraction methods. Milling efficiency and energy efficiency of milling process were studied in conditions with and without powder fluidization by magnetic fields. Analysis of experimental data showed advantages of milling in magneto fluidized bed in increased efficiency, particle size distribution homogeneity and powder chemical activity because of lattice micro-stresses.