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The study has revealed the regularities of the effect produced by increasing the content of scale of steel 12Cr18Ni10Ti in the charge from 5 to 75 mass % on the contents of the products of carbon thermal reduction of oxide waste of corrosion-resistant steels. The concentration of Ni is increased from 0.8 to 7.0 mass % when the Cr content ranges from 15.9 to 17.1 mass %. The concentration of Cr in the extraction products within the range of 16.1–17.1 mass% is provided with the content of scale of 95Cr18 steel in the charge in the range from 5 to 55 mass %. It has been found that metallization products mainly consist of a solid solution of alloying elements in α-Fe. Fe3O4, Fe3C, and Fe2C were also identified. The microstructure of the extraction products is spongy and disordered. The particles are sintered, with varying Cr and Ni contents in the ranges of 7.47 to 18.03 mass % and 2.97–10.40 mass %, respectively. The study has helped achieve environmentally safe conditions for solid-phase extraction of chrome and nickel containing industrial wastes from the production of corrosion-resistant steels with the return of the alloyed product to the welding industry, Определены закономерности влияния параметров шихты на содержание Cr и Ni в продуктах восстановления. Достигнуты пределы содержания соответствующих элементов: 15,1–17,1 % мас. и 0,2–7,0 % мас. Установлено, что продукты металлизации в основном состояли из твердого раствора легирующих элементов в α-Fe. Также выявлены оксид Fe3O4 и карбиды – Fe3C, Fe2C. Микроструктура губчатая разупрядоченная. Микрочастицы спеченные, с различным содержанием Cr и Ni, Визначено закономірності впливу параметрів шихти на вміст Cr та Ni в продуктах відновлення. Досягнуто межі вмісту відповідних елементів: 15,1–17,1 % мас. та 0,2–7,0 % мас. Встановлено, що продукти металізації в основному складалися з твердого розчину легуючих елементів в α-Fe. Також виявлено оксид Fe3O4 і карбіди – Fe3C, Fe2C. Мікроструктура губчаста розупорядкована. Мікрочастки спечені, з різним вмістом Cr та Ni

The study has determined an increase of the degree of thermal carbon extraction of the molybdenum oxide concentrate from 11 % to 97 % with an increase in the processing temperature from 873 K to 1373 K, respectively. A further rise in temperature to 1473 K led to a reduction in the degree of recovery to 89 %. The recovery products after treatment at 873–1073 K mostly consisted of MoO2 with some Mo and Mo2C manifestations. Treatment at 1223–1473 K provided a predominance of Mo and Mo2C as to the oxide component. The microstructure of the recovery products was spongy and disordered with varying degrees of sintering, depending on the processing temperature. The alloying of R6M5 steel with the new molybdenum material in experimental industrial conditions provided an increase in the Mo uptake rate from 88.9 % to 95.0 % compared with the standard technology. Improvement of environmental safety is achieved by replacing carbon monoxide and aluminothermic melting of ferroalloy production of Mo with the latest methods of powder metallurgy., Визначено кінетичні закономірності вуглецевотермічного відновлення оксидного молібденового концентрату в інтервалі 873–1473 K. Найвищий ступінь відновлення 97 % досягнуто після обробки при 1373 K із переважанням у фазовому складі Mo. Мікроструктура – губчаста розупорядкована. Поліпшення екологічної безпеки досягається заміною вуглецевосиліко- та алюмотермічної плавок феросплавного виробництва Mo на новітні методи порошкової металургії, Определены кинетические закономерности углеродотермического восстановления оксидного молибденового концентрата в интервале 873–1473 K. Наибольшая степень восстановления 97 % достигнута после обработки при 1373 K с преобладанием в фазовом составе Mo. Микроструктура – губчатая разупорядоченная. Улучшение экологической безопасности достигается заменой углеродосилико- и алюмотермической плавок ферросплавного производства Mo на новейшие методы порошковой металлургии

Moduli for numerical finding of the polynomial of the best Hausdorff approximation of the functions which differs from zero at just one point or having one jump and partially constant in programming environment MATHEMATICA are proposed. They are tested for practically important functions and the results are graphically illustrated. These moduli can be used for scientific research as well in teaching process of Approximation theory and its application., ACM Computing Classification System (1998): G.1.2.

Hausdorff distance (HD) seems the most efficient instrument for measuring how far two compact non-empty subsets of a metric space are from each other. This paper considers the possibilities provided by HD and some of its modifications used recently by many authors for resemblance between binary text images. Summarizing part of the existing word image matching methods, relied on HD, we investigate a new similar parameterized method which contains almost all of them as particular cases. Numerical experiments for searching words in binary text images are carried out with 333 pages of old Bulgarian typewritten text, 200 printed pages of Bulgarian Chrestomathy from year 1884, and 200 handwritten pages of Slavonic manuscript from year 1574. They outline how the parameters must be set in order to use the advantages of the proposed method for the purposes of word matching in scanned document images., This work has been partially supported by Grant No. DO 02-275, 16.12.2008, Bulgarian NSF, Ministry of Education and Science.

Purpose. To report a rare case of secondary epiretinal membrane (ERM) spontaneous separation with subsequent visual restoration. Case Summary. We are reporting a case with the history of branch retinal vein occlusion, peripheral retinal neovascularization, and retinal photocoagulation. Our examination revealed secondary ERM associated with relatively high visual acuity (0.6), and a watchful waiting strategy was chosen. During the follow-up, slight visual deterioration, progressive deformation of the retinal profile, and an increase in diffuse retinal edema were observed. No surgical or laser treatment was performed. On the next visit, the spontaneous ERM separation with residual parapapillary fixation, the increase in visual acuity (0.9), and the decrease in retinal thickness were revealed. Conclusion. Such cases present additional evidence to a deferral surgical strategy for the management of patients with ERM and relatively high visual acuity.