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It is shown that the Yb2O3–Bi2O3–B2O3 system gives a new Yb3Bi2B5O15 compound of a hexagonal crystallographic system. Based on the data on the nature of specimens and by means of X-ray study of obtained samples, we determined the boundaries of glass-formation regions in the Yb2O3–Bi2O3–B2O3 system. Homogeneous glasses were obtained in the following cuts: Bi2O3⋅B2O3 − Lu2O3–B2O3 up to 15 mol % Lu2O3; Lu2O3⋅B2O3−Bi2O3 up to 10 mol % Lu2O3; Bi2O3⋅B2O3 − Lu2O3⋅Bi2O3 up to 15 mol % Lu2O3. Eutectic coordinates of LnBO3– B2O3 (Ln = Се, Pr, Pm, Sm, Tb, Er) systems were calculated at first.

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Using the methods of differential thermal analysis and X-ray powder diffraction, the Т–х phase diagram of the Li2O⋅2B2O3–Yb2O3⋅B2O3 system has been constructed. Phase diagram of this system belongs to the eutectic type and is characterized by the formation of limited Li2O⋅2B2O3–based solid solutions. The region of limited (1 – х)Li2O⋅B2O3–хYb2O3⋅B2O3 solid solutions at 298–1038 K is x = 0–0.1 mole fraction of Yb2O3⋅B2O3 (or α-Li2O⋅2B2O3). Eutectic coordinates: 1038 K and ~17 mol % Yb2O3⋅B2O3. Depending on the thermal history, (1 – х)Li2O⋅2B2O3–хYb2O3⋅B2O3 (x = 0–0.1) solid solutions are formed both in the form of polycrystals (annealed) and in the form of amorphous glasses (quenched). Glassy and polycrystalline samples of solid solutions α-Li2O⋅2B2O3 (x = 0, 0.05, and 0.1) were synthesized and their physico-chemical properties were studied. The temperature dependence of the standard Gibbs energy of the reaction of formation of solid solutions is estimated (0 ≤ х ≤ 0.1 at 573–1073 K). It is shown that the formation reaction of a solid solution based on Li2O⋅2B2O3 in the range 0 ≤ х ≤ 0.1 mole fraction Yb2O3⋅B2O3 is thermodynamically possible under standard conditions. Measured the electrical properties of (1 – х)Li2O⋅2B2O3–хYb2O3⋅B2O3 (x = 0, 0.05, 0.1) glass samples solid solutions (x = 0–0.1) in the temperature range from 298 to 575 K. The temperature dependences of the direct current (dc) conductivity of α-Li2O⋅2B2O3–samples with different thermal histories (annealing or quenching) differ from each other. It was shown that the introduction of Yb2O3⋅B2O3 (x = 0–0.1) into (1 – х)Li2O⋅2B2O3–хYb2O3⋅B2O3 glasses reduces the conductivity of the samples. The activation energies of conductivity of the glass samples are determined (66.6–90.7 kJ/mol). At temperatures >575 K, the conductivity of α-Li2O⋅2B2O3 glasses deviates from the Arrhenius equation. [ABSTRACT FROM AUTHOR]

Screening for latent tuberculosis infection before solid organ transplantation is mandatory, but this is not so easy in uremic patients on hemodialysis (HD) treatment. The newly developed interferon-gamma (IFN-γ)-based QuantiFERON®–TB Gold In-Tube test (QFT-G) seems to be superior to the other available tests. Objective. To investigate the acute effect of the low-flux HD process on the results of the QFT-G assay. Methods. A total of 56 HD patients participated in this prospective study. They were dialyzed under low-flux HD for at least 1 month before blood sampling for QFT-G assay. This assay was performed before and after the 4-h low-flux HD session. Results. Compared with the pre-dialysis level, there was an obvious reduction in the IFN-γ production level (in response to the TB-antigen cocktails) after the HD process ( P=0.00). The pre-dialysis test result was negative in 21 (37.5%), positive in 33 (58.9%), and indeterminate in 2 (3.6%) patients. One pre-dialysis negative result changed to positive after the HD process. On the other hand, 7 pre-dialysis positive and 2 indeterminate results become negative after HD ( P=0.012). Conclusion. In order to maintain the sensitivity of QFT-G assay in chronic renal failure patients on low-flux HD treatment, it is better to perform the test immediately before (not after) the HD process. [ABSTRACT FROM AUTHOR]