Formation of competitive advantages of iron-ore mining enterprises

Розглянуто формування показника конкурентоспроможності гірничозбагачувального підприємства з урахуванням резервів, технологічних і економічних факторів підвищення його конкурентних переваг при реалізації кінцевої продукції на внутрішньому і зовнішньому ринку залізорудної сировини в умовах невизначеності.Рассмотрено формирование показателя конкурентоспособности горно-обогатительного предприятия с учетом резервов, технологических и экономических факторов повышение его конкурентных преимуществ при реализации конечной продукции на внутреннем и внешнем рынке железорудного сырья в условиях неопределенности.The formation of competitiveness mining and processing enterprise including reserves, technological and economic factors ditch increase its competitive advantage in the sales of final products on the domestic and foreign market of iron ore raw materials in conditions of uncertainty

Using ellipsometry methods for depth analyzing the optical disc data layer relief structures

We studied the relief depth of the data layer formed in a glass disk by ion beam etching process with using classical ellipsometry at the constant wavelength 632.8 nm for different angles of incidence. It was found that for 0° and 90° azimuth angles, a pair of ellipsometric parameters Ψ and ∆ is sufficient to characterize the changes in light reflection for various structure depths. The depth of optical disc data layer relief structures was estimated via experimental dependences of ellipsometric parameters. The estimated data layer depths were found to be in good agreement with independent tunnelling electron microscopy measurements

Luminescence of the pyrazoline dye in nanostructured zeolite matriх

A physicotechnical fundamental of the multilayer photoluminescent media development has been considered. The quantum yield and relaxation time of luminescence were found as most significant values of the recording material. Organic pyrazoline dyes were adopted due to their appropriable characteristics. Possibility of the further luminescent material parameters increase while performance dye molecules in the white nanostructured zeolite matrix by components mixing and laser annealing was proposed. Experimental results with 60 % of quantum yield gain and relaxation time quadruple decrease was obtained. Using the received materials in plotting the identification luminescent elements based on the optical disc cover procedure has been determined

Optical properties of graphene film growing on a thin copper layer

Optical properties and surface structure of graphene films grown on thin 1-μm copper layer using the chemical vapor deposition method were investigated applying spectroscopic ellipsometry and nanoscopic measurements. Angle-variable ellipsometry measurements were performed to analyze features of optical conductivity and dispersion of the complex refraction index. Significant enhancement of the absorption band in the graphene single layer with respect to the bulk graphite was observed due to interaction between excited localized surface plasmon at the surface of thin Cu layer and graphene’s electrons. Scanning tunneling microscopy measurements with atomic spatial resolution revealed vertical crystal lattice structure of the deposited graphene layer. The obtained results provide direct evidence of the strong influence of the growth conditions on electronic and optical behavior of graphene films

Optical and magneto-optical properties of thin films for high density information recording

It was found that optical and magneto-optical (MO) properties of thin film materials have potential application for blue laser recording. For this purpose, we have used a combination of ellipsometric and polar MO Kerr effect measurements. The optical and magneto-optical properties of Mn(Sb₁-xBix) and Co-Pt nanocrystalline films were investigated for incident photons in the energy range from 1.3 to 4.0 eV. A large Kerr rotation angle of about 0.570 was observed at photon energy hw»2.65 eV for the Mn₅₅Sb₃₆Bi₉ film with an average grain size of 30 nm. The changes of the exchange splitting and the spin-orbit interaction strength are responsible for the strong dependence of Kerr effect in Mn(Sb₁-xBix) nanocrystalline films. It was shown that the large MO polar Kerr rotation angle is correlated with a perpendicular magnetic anisotropy in nanocrystalline Co₃Pt film

TMR, MRE, and X-ray photoelectron spectroscopy of Fe-SiO₂ granular films

Feₓ(Si0₂)₁₋ₓ magnetic granular films below the percolation threshold (х < 0.45) have been studied using tunneling magnetoresistance (TMR), magnetorefractive effect (MRE), and X-ray photoelectron spectroscopy. Maximum magnetoresistance ratio of 3.7 % at room temperature was observed for films of Fe₀.₃₅(Si0₂)₀.₆₅ composition. Both the experimental and theoretical analysis reveal a correlation between TMR and MRE, thus demonstrating the usage possibility of the MRE as a contactless method to measure the TMR. The chemical surface structure was analyzed by X-ray photoelectron spectroscopy (XPS) and compared to that of the corresponding Si0₂ and Fe surfaces. The XPS spectra of Feₓ(Si0₂)₁₋ₓ granular films display two main peaks at 707 and 720 eV, which arise from Fe 2р₃/₂ and Fe 2р₁/₂, respectively, and a small peak appears around 710.5 eV due to Fe₂0₃.Магнитные гранулированные пленки Feₓ(Si0₂)₁₋ₓ с содержанием металла ниже порога перколяции изучены с помощью туннельного магнитосопротивления, магниторефрактивного эффекта и рентгеновской фотоэлектронной спектроскопии. Максимальное значение магнитосопротивления 3,7 % при комнатной температуре было обнаружено для пленок Fe₀.₃₅(Si0₂)₀.₆₅. Экспериментальные результаты и теоретический анализ показывают корреляцию между туннельным магнитосопротивлением (ТМС) и магниторефрактивным эффектом (МРЭ), что позволяет использовать МРЭ в качестве бесконтактного метода измерения ТМС. Химический состав поверхности пленок проанализирован с помощью рентгеновской фотоэлектронной спектроскопии (РФС) и проведено его сравнение с поверхностями Si0₂ и Fe. РФС спектры гранулированных пленок Feₓ(Si0₂)₁₋ₓ характеризуются двумя полосами, локализованными при энергиях 707 и 720 эВ, которые связаны с Fe 2р₃/₂ и Fe 2р₁/₂ энергетическими уровнями. Также наблюдался незначительный пик при 710,5 эВ благодаря вкладу Fe₂0₃.Магнiтнi гранулярнi плiвки Feₓ(Si0₂)₁₋ₓ iз змiстом металу, нижчим за перколяцiйний порiг, дослiджувались за допомогою тунельного магнiтоопору, магнiторефрактивного ефекту та рентгенiвської фотоелектронної спектроскопiї. Максимальне значення магнiтоопору 3,7 % при кiмнатнiй температурi було знайдено для плiвок Fe₀.₃₅(Si0₂)₀.₆₅. Експериментальнi результати та теоретичний аналiз показують кореляцiю мiж тунельним магнiтоопором (ТМО) та магнiторефрактивним ефектом (МРЕ). Це дозволяє використовувати МРЕ для безконтактного вимiрювання ТМО. Хiмiчний склад поверхнi плiвок Feₓ(Si0₂)₁₋ₓ аналiзувався за допомогою рентгенiвської фотоелектронної спектроскопiї (РФС) та порiвнювався з даними для поверхонь Si0₂ i Fe. РФС-спектри гранульованих плiвок Feₓ(Si0₂)₁₋ₓ характеризуються двома смугами при енергiях 707 та 720 еВ, якi вiдповiдають енергетичним рiвням Fe 2р₃/₂ та Fe 2р₁/₂. Також спостерiгався незначний максимум при 710,5 еВ завдяки внеску Fe₂0₃

Characterization and optical properties of organic dye films as recording media

Efficiency of medium choice for optical information recording is generally determined by homogeneity degree of material on the recording surface and by its structure on the film depth. In this respect pyrosolynes should be the prospective materials. Pyrosolyne dye films were produced on the glass substrates initially remained at room temperature T = 20°C by using different techniques such as vapor deposition and sol-gel modified reactions. One of the precise control methods of material surface physical-chemical state is ellipsometric method. In addition, the optical transmission measurements were carried out for these films within the wavelength range λ = 200-630 nm at two different polarization (p- and s-) of the incident light. It has been shown that the absorption bands near n = 1300 cm⁻¹ are present in ellipsometric parameters spectra in case of the vapor deposited dye film samples. The transmission optical measurements of organic films in the visible range without polarizer showed presence of the absorption bands near λ = 300 and 520 nm. The first absorption band was much more intensive than another. It has been determined that the transmission values measured in polarized in p- and s-directions light differs by 5-8% in comparison with data measured without polarizer

Ellipsometry and optical spectroscopy of low-dimensional family TMDs

Here, we report a comprehensive study of fundamental optical properties of two-dimensional materials. These properties have been ascertained using spectroscopic ellipsometry, optical spectroscopy of Raman scattering, and photoluminescence. We have focused on optical properties of the chemically exfoliated layered TMDs: MoS2, MoSe2, WS2, and WSe2. The complex refractive index and optical conductivity within the region 1 to 4.5 eV were extracted, which lead to identification of many unique interband transitions at high symmetry points in the electron band structure. The positions of the so-called A and B excitons in monolayers are found to shift upwards in energy as compared with those of the bulk form and have smaller separation because of the decreased interactions between the layers. For monolayer TMDs, the valence-band spin-orbit splitting at the K point was estimated from the energy difference between the A and B exciton peaks. Our findings of the spin-orbit coupling of 0.16, 0.26, 0.37, and 0.55 eV in monolayers MoS2, MoSe2, WS2, and WSe2, respectively. All these findings not only extend our understanding the novel electronic structures of mono- and few-layers TMDs but also provide foundation for future technological applications of optoelectronic and spintronic device components

Optical properties of the modified structures of surface layers of amorphous metallic alloy ribbons

Modification of the microrelief and structure of a CO-based amorphous metal alloy ribbon surface layers after thermal treatment at elevated and cryogenic temperatures and under an external magnetic field has been studied using light scattering method and atomic force microscopy. The surface roughness parameters were calculated from the experimental light scattering indicatrices. It is shown that heating of the metal ribbons to Т - 350-475 ℃ relieves partially the stresses arising in the course of the ribbon prepara- tion and increases the surface roughness as compared to that of as-prepared samples.Модифiкацiя мiкрорельефа i структури поверхневих шарiв стрiчок аморфних сплавiв на основi CO пiсля термiчної обробки при пiдвищених та крiогенних температурах, пiд дiєю прикладеного магнiтного поля вивчена методом розсiяння свiтла i атомно-силовою мiкроскопiею. Параметри шорсткостi поверхнi розраховано iз експериментально отриманих iндикатрис iнтенсивностi розсiяння свiтла. Показано, що нагрiвання металевих стрiчок до Т = 350-475 ℃ частково знiмає напруження, що виникае пiд час виготовлення стрiчки, i пiдвищує шорсткiсть поверхнi порiвняно з тiєю, яка характерна для щойно виготовлених зразкiв.Модификация микрорельефа и структуры поверхностных слоев лент аморфных сплавов на основе Cо после термической обработки при повышенных и криогенных температурах, под действием приложенного магнитного поля изучена методом рассеяния света и атомно-силовой микроскопией. Параметры шероховатости поверхности лент рассчитаны из экспериментально полученных индикатрис интенсивности рассеянного света. Показано, что нагревание металлических лент до Т = 350-475 ℃ частично снимает напряжения, возникающие во время изготовления ленты, и повышает шероховатость поверхности по сравнению с той, которая характерна для свежеизготовленных образцов