INTERACTION OF THE LANTHANA, YTTRIA WITH YTTERBIA AT TEMPERATURE 1500 °C

Phase equilibria in the ternary La2О3–Y2O3–Yb2О3 system at 1500 °C were studied by X–ray diffraction and petrography in the overall concentration range. The samples of different compositions have been prepared from nitrate acid solutions by evaporation, drying, and calcinations at 1100 and 1500 ºC. The solid solutions based on various polymorphous forms of constituent components and ordered phases of LaYO3 (LaYbO3) were revealed in the system. The boundaries of mutual solubility and concentration dependences the lattice parameters for all phases have been determined

ВЗАЄМОДІЯ ОКСИДІВ ЛАНТАНУ, ІТРІЮ ТА ІТЕРБІЮ ПРИ ТЕМПЕРАТУРІ 1500 ºС

Phase equilibria in the ternary La2О3–Y2O3–Yb2О3 system at 1500 °C were studied by X–ray diffraction and petrography in the overall concentration range. The samples of differentcompositions have been prepared from nitrate acid solutions by evaporation, drying, and calcinations at 1100 and 1500 ºC. The solid solutions based on various polymorphous forms ofconstituent components and ordered phases of LaYO3 (LaYbO3) were revealed in the system. The boundaries of mutual solubility and concentration dependences the lattice parameters for all phases have been determined.Вперше досліджено фазові рівноваги у потрійній системі La2O3–Y2O3–Yb2O3 при температурі 1500 °С у всьому інтервалі концентрацій. Зразки різних складів отриманіз розчинів азотнокислих солей випарюванням, сушкою і термообробкою при температурах 1100 та 1500 ºC. За допомогою рентгенофазового аналізу та петрографії вста-новлено, що в системі утворюються тверді розчини на основі різних кристалічних модифікацій вихідних компонентів та упорядкованих фаз типу перовскиту. Визначено границі розчинності та концентраційні залежності періодів кристалічних ґраток фаз, що утворюються у системі

ФАЗОВІ РІВНОВАГИВ СИСТЕМІ ZrO2–DY2O3 ПРИ 1100 °С

Phase equilibria in the binary ZrO2– Dy2O3system at 1100°C were studied by X-ray diffraction and petrography in the overall concentration range. The samples of different compositions have been prepared from nitrate acid solutions by evaporation, drying, and calcinations at 1100ºC. The solid solutions based on various polymorphous forms of constituent phases were observed. The boundaries of mutual solubility and concentration dependences the lattice parameters for all phases have been determined. It was established that in the ZrO2–Dy2O3 system there exist fields of solid solutions based on cubic (C) modification of Dy2O3, tetragonal (T) crystal modifications of ZrO2, cubic modification of ZrO2 with fluorite-type structure (F). The boundaries of the homogeneity fields for F-ZrO2 and C-Dy2O3 solid solutions (were determined from samples containing 85-100 mol % Dy2O3 at heat treatment (12604 h). The lattice parameter of the unit cell decreased from а = 1.0655 nm in pure ZrO2 to а= 1.0602 nm for sample containing 20 mol % ZrO2. The solubility of Dy2O3in the T-ZrO2is low and amounts to 0.5 mol%, as evidenced by XRD analysis results. The homogeneity field of F-ZrO2in the concentration range of 90-58 mol % ZrO2at 1100 °C was established. The lattice parameters of the unit cell F-ZrO2 varies from а = 0.5161 nm for sample containing 85 mol % ZrO2 to а = 0.5235 nm for sample containing 60 mol % ZrO2Досліджено фазові рівноваги в подвійній системі ZrO2–Dy2O3при 1100 °С в усьому інтервалі концентрацій. Зразки отримані з розчинів азотнокислих солей випарюванням,сушкою і термообробкою при температурі 1100 °C. За допомогою методів рентгенофазового аналізу та петрографії встановлено, що в системі утворюються тверді розчини на основі різних кристалічних модифікацій вихідних компонентів. Визначено границі розчинності та концентраційні залежності параметрів елементарних комірок фаз, що утворюються в системі

PHASE EQUILIBRIA IN THE ZrO2 – Dy2O3 SYSTEM AT 1100°C

Phase equilibria in the binary ZrO2– Dy2O3system at 1100°C were studied by X-ray diffraction and petrography in the overall concentration range. The samples of different compositions have been prepared from nitrate acid solutions by evaporation, drying, and calcinations at 1100ºC. The solid solutions based on various polymorphous forms of constituent phases were observed. The boundaries of mutual solubility and concentration dependences the lattice parameters for all phases have been determined. It was established that in the ZrO2–Dy2O3 system there exist fields of solid solutions based on cubic (C) modification of Dy2O3, tetragonal (T) crystal modifications of ZrO2, cubic modification of ZrO2 with fluorite-type structure (F). The boundaries of the homogeneity fields for F-ZrO2 and C-Dy2O3 solid solutions (were determined from samples containing 85-100 mol % Dy2O3 at heat treatment (12604 h). The lattice parameter of the unit cell decreased from а = 1.0655 nm in pure ZrO2 to а= 1.0602 nm for sample containing 20 mol % ZrO2. The solubility of Dy2O3in the T-ZrO2is low and amounts to 0.5 mol%, as evidenced by XRD analysis results. The homogeneity field of F-ZrO2in the concentration range of 90-58 mol % ZrO2at 1100 °C was established. The lattice parameters of the unit cell F-ZrO2 varies from а = 0.5161 nm for sample containing 85 mol % ZrO2 to а = 0.5235 nm for sample containing 60 mol % ZrO

ФАЗОВІ РІВНОВАГИ В СИСТЕМІ ZrO2–Yb2O3 ПРИ 1100 °С

Phase equilibria in the binary ZrO2 – Yb2O3 system at 1100°C were studied by X-ray diffraction and petrography in the overall concentration range. The samples of different compositions have been prepared from nitrate acid solutions by evaporation, drying, and calcinations at 1100ºC. To study phase relationships at 1100°C the as-prepared samples were thermally treated in the furnace with heating elements based on Fecral (H23U5T) at 1100°C (for 12415 in air). The heating rate was 3.5°C/min. It was established that in the ZrO2–Yb2O3 system there exist fields of solid solutions based on cubic (C) modifi cation of Yb2O3, tetragonal (T) crystal modifications of ZrO2, cubic modifi cation of ZrO2 with fluorite-type structure (F) and δ-phase of Yb4Zr3O12 which are separated by wide two phase fields (F + T) and (F + δ) and (δ+C). The boundaries of the homogeneity fi eld for C-Yb2O3 solid solutions were determined from samples containing 80-100 mol % Yb2O3 at heat treatment 1100°C (12415 h). The lattice parameter of the unit cell decreased from а = 1.043 nm in pure Yb2O3 to а = 1.0402 nm for sample containing 25 mol % ZrO2- 75 mol % Yb2O3. The solubility of Yb2O3 in the T-ZrO2 is low and amounts to 0.5 mol%, as evidenced by XRD analysis results. It is the solid solutions based on tetragonal modification of zirconia cannot be quenched from high temperatures due to low stability of T-ZrO2 under cooling with furnace conditions. The diffraction patterns recorded at room temperatures included the peaks of monoclinic phase M-ZrO2 was found. The homogeneity fi eld of F-ZrO2 in the concentration range of 85-75 mol % ZrO2 at 1100 °C was established. The lattice parameters of the unit cell increased from а = 0.5124 nm for sample containing 85 mol % ZrО2-15 mol % Yb2O3 to а = 0.5152 nm the two-phase (F+δ) sample containing 75 mol % ZrО2-25 mol % Yb2O3Досліджено фазові рівноваги в подвійній системі ZrO2–Yb2O3 при температурі 1100 °С в усьому інтервалі концентрацій. Зразки отримані з розчинів азотнокислих солей випарюванням, сушкою і термообробкою при температурі 1100 °C. Для дослідження взаємодії в системі ZrО2–Yb2O3 при 1100 °С термообработку зразків проводили в печі з нагрівачами H23U5T (фехраль) 12342 год. Зразки нагрівали від кімнатної до потрібної температури із швидкістю 3.5 град/хв. Охолодження проводили разом з піччю. За допомогою δметодів рентгенофазового аналізу та петрографії встановлено, що в системі утворюються тверді розчини на основі тетрагональної (Т) і кубічної (F) модифікацій ZrО2, кубічної (С) модифікації Yb2O3, а також впорядкованої δ-фази (Yb4Zr3O12), що кристалізується в ромбоедричній структурі, які розділені двофазними полями (F + T), (F + δ) та (δ +С), відповідно. Границі області гомогенності С-Yb2O3 складають 80-100 мол. % Yb2O3 при 1100 °С. Параметри елементарних комірок твердих розчинів зменшуються від а =1.043 нм для чистого Yb2O3 до а = 1.0402 нм для гетерогенного складу (δ +С), що містить 25 мол. % ZrО2-75 мол. % Yb2O3 при 1100 °С. Тверді розчини на основі тетрагональної модифікації ZrO2 при заданих умовах не загартовуються, замість них спостерігали утворення моноклінної M- модифікації ZrO2. Розчинність Yb2О3 в Т-ZrO2 невелика і складає 0.5 мол. %. Встановлено границі двофазної області (Т + F), яка простягається від 0.5 до 15 мол. % Yb2O3. Зразки, що містять 99.5 мол. % ZrO2-0.5 мол. % Yb2O3, 90 мол. % ZrO2-10 мол. % Yb2O3 визначають границі двофазної області (F + Т). Область гомогенності твердих розчинів на основі F-ZrO2 простягається від 85 до 75 мол. % ZrO2. Параметри елементарних комірок змінюються від а = 0.5124 нм для зразка, що містить 85 мол.% ZrО2-15 мол. % Yb2O3 до а = 0.5152 нм для гетерогенного складу (F + δ), що містить 75 мол. % ZrО2-25 мол. % Yb2O3

ВЗАЄМОДІЯ ОКСИДІВ ЛАНТАНУ, ІТРІЮ ТА НЕОДИМУ ПРИ ТЕМПЕРАТУРІ 1600 °С

First, the phase equilibria in the ternary La2О3–Y2O3–Nd2О3 system at 1600 °C were studied by X–ray diffraction and petrography in the overall concentration range. The samples of different compositions have been prepared from nitrate acid solutions by evaporation, drying, and calcinations at 1100, 1500 and 1600 °C. It was established that in the system there exist fields of solid solutions based on cubic (C) modification of Y2O3, hexagonal (А) and monoclinic (В) modifications of La2O3 and Nd2O3. The isothermal section has been developed. The systematic study that covered whole composition range excluded formation of new phases. The isothermal section of the La2О3–Y2O3–Nd2О3 system at 1600 °С is characterized by three homogeneity fields (А, B, С) and two two-phase (A + B, B + С ) fields. The lattice parameters of the unit cells and the boundaries of the homogeneity fields for solid solutions were determined. The homogeneity field of solid solutions based on В-phase extends from 33 tо 44 mol.% Y2O3 along the section Y2О3 – (90 mol % La2О3 – 10 mol% Nd2O3) and from 33 tо 43 mol% Y2O3 along the section Y2О3 – (50 mol % La2О3 – 50 mol % Nd2O3). The homogeneity field of A-phase was revealed to extend from 0 tо 19 mol % Y2O3 along the section Y2О3 – (90 mol% La2О3 – 10 mol % Nd2O3).Вперше за допомогою методів рентгенівського фазового аналізу та петрографії досліджено фазові рівноваги у потрійній системі La2O3–Y2O3–Nd2O3 при 1600 °С у всьому інтервалі концентрацій. Встановлено, що в системі утворюються тверді розчини на основі кубічної (С) модифікації Y2O3, гексагональної (А) та моноклінної (В) модифікацій La2O3 і Nd2O3. Визначено границі розчинності та параметри елементарних комірок твердих розчинів

INTERACTION OF THE LANTHANA, YTTRIA WITH NEODYMIA AT TEMPERATURE 1600 °C

First, the phase equilibria in the ternary La2О3–Y2O3–Nd2О3 system at 1600 °C were studied by X–ray diffraction and petrography in the overall concentration range. The samples of different compositions have been prepared from nitrate acid solutions by evaporation, drying, and calcinations at 1100, 1500 and 1600 °C. It was established that in the system there exist fields of solid solutions based on cubic (C) modification of Y2O3, hexagonal (А) and monoclinic (В) modifications of La2O3 and Nd2O3. The isothermal section has been developed. The systematic study that covered whole composition range excluded formation of new phases. The isothermal section of the La2О3–Y2O3–Nd2О3 system at 1600 °С is characterized by three homogeneity fields (А, B, С) and two two-phase (A + B, B + С ) fields. The lattice parameters of the unit cells and the boundaries of the homogeneity fields for solid solutions were determined. The homogeneity field of solid solutions based on В-phase extends from 33 tо 44 mol.% Y2O3 along the section Y2О3 – (90 mol % La2О3 – 10 mol% Nd2O3) and from 33 tо 43 mol% Y2O3 along the section Y2О3 – (50 mol % La2О3 – 50 mol % Nd2O3). The homogeneity field of A-phase was revealed to extend from 0 tо 19 mol % Y2O3 along the section Y2О3 – (90 mol% La2О3 – 10 mol % Nd2O3)

Market Discipline and the Russian Interbank Market

The interbank market plays an important role in the overall function of the financial system. The efficiency of the interbank market, in turn, depends largely on its inherent disciplining mechanisms. This paper investigates the discipline mechanisms of Russia's interbank market, testing the hypothesis that market discipline in Russia was strong enough to constrain excessive risk-taking by participating banks before, during, and after the 2008- 2009 financial crisis. The existence of quantity-based market discipline is investigated using Heckman's sample selection model and the efficiency of market discipline is studied with a panel data model. Our approach detects market discipline only during the financial crisis, not before or after. Even during the crisis, its efficiency in curbing bank risk-taking was rather low

X-RAY MORPHOLOGICAL SEMIOTICS OF NON-TUBERCULOUS MYCOBACTERIAL PULMONARY DISEASE

Objective: to evaluate the X-ray radiological features of nontuberculous mycobacterial pulmonary disease (NTMPD) versus morphological findings.Material and methods. The investigation enrolled 37 patients, in whom the radiographic signs of dissemination were determined and various types of NTMPD were identified. The investigation was conducted on a Siemens Somatom Emotion 16 multislice computed tomography (MSCT) scanner using a high-resolution algorithm (Quick Time Virtual Reality). To clarify the activity of pathological changes in the thoracic organs, 16 (43.2%) patients underwent a radionuclide study with 99mTc-technetrile on a Nucline Spirit gamma camera in planar and single photon emission computed tomography modes.The diagnosis was verified by sputum smear microscopy and clinical laboratory and bronchologic examinations: bronchoalveolar lavage in 11 (29.7%) patients, various types of bronchial biopsies in 17 (46.0%), morphological examinations, and videoassisted thoracoscopic surgery for pulmonary resection in 9 (24.3%).Results. The dissemination foci in mycobacterial diseases were characterized by their location in the lung parenchyma with vascular and bronchial involvement and reactive changes in the pulmonary pleurae and intrathoracic lymph nodes (ITLN). In 92.7% of cases, the detected foci were predominantly centrilobular with endobronchial localization. Their contours were mixed with clear and fuzzy outlines in 98.7% of cases. In 70.3% of cases, the foci were asymmetrically localized mainly in the subpleural areas of the lung and 12.3% of cases were accompanied by reactive involvement of the visceral pleura.CT study revealed a tree-in-bud sign in 96.7% of cases, frosted glass in 10.2%, and mosaic perfusion in 13.2%. A more than 10-mm increase in ITLN was found in 11.7% of cases.In a number of cases, it was difficult to speak about the activity of the pathological process in the lung and ITLN, as shown by MSCT. In this case, a lung radionuclide study with 99mTc-technetrile was carried out in the planar mode. The degree of tracer accumulation, localization, and extent were analyzed in the planar mode.Conclusion. Thus, the CT typical signs of NTMPD are the asymmetric location of its foci with an endobronchial extension, peribronchovascular localization of foci; the presence of a CT tree-in-bud sign; and the slight involvement of the pulmonary pleurae in the process. 99mTs-technetril radionuclide study has established that the most active inflammatory process is located in the lung and the tracer accumulates in the pathologically altered lymph nodes