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TeO2–ZnO–MoO3 glasses containing cobalt(II) ions in the concentration range from 0.035 to 1.2 wt % have been prepared using orthotelluric acid, ammonium heptamolybdate, zinc nitrate, and cobalt(II) nitrate as starting materials. In the wavelength range from 0.42 to 3.0 μm, the transmission spectra of the glasses contain two strong absorption bands, peaking at ~584 and ~1357 nm. Using a series of glasses doped with 3.5 × 10–2 to 1.2 wt % cobalt, the specific absorption coefficient of Co2+ ions has been determined (3550 ± 210 dB/(km ppm) at 584 nm) and its spectral dependence has been obtained in the wavelength range studied.

Intratissue radiotherapy with Co60 sources in combination with gamma-teletherapy was used in 11 patients with penile carcinoma as organpreserving treatment. In this group of patients, 5-year relapse-free survival was 91.6%. Along with high survival rates, this treatment modality assured a high quality of life. Combined radiotherapy is most effective and advisable in patients with T1-T2.

(TeO2)0.70(ZnO)0.30 tellurite glasses doped with Cr3+ ions in the concentration range 80 to 2500 ppm have been prepared via melt solidification using orthotelluric acid and zinc nitrate, and their optical transmission has been measured in the wavelength range 0.3 to 2.7 μm. Transmission spectra of the glasses have been shown to contain two strong absorption bands, peaking at 460 and 650 nm. Using a series of glasses differing in chromium content, we have evaluated the spectral dependence of the specific absorption coefficient for the glasses, which has been shown to be 142 ± 2 cm–1/wt % at the maximum of the 650-nm absorption band.

We have investigated the coprecipitation of tellurium(IV), tungsten(VI), and lanthanum(III) hydroxides through the addition of aqueous ammonia to a mixture of tellurium dioxide, lanthanum oxide, and tungstic acid solutions in hydrochloric acid. The effects of initial solution composition and precipitation pH on the composition of the precipitate have been assessed. It has been shown that the composition of the precipitate is essentially identical to that of the starting solution if the relative contents of lanthanum and tungsten in the mixture are within 20 mol % and precipitation is ceased at pH 7.

We have investigated the coprecipitation of tellurium(IV), molybdenum(VI), and lanthanum(III) hydroxides from hydrochloric acid solutions of compounds of these elements and found conditions under which the precipitate was identical in composition to the starting solution of macrocomponents.

We have investigated the coprecipitation of tellurium(IV) and tungsten(VI) compounds through the addition of aqueous ammonia to a mixture of a tellurium dioxide solution in hydrochloric acid and tungstic acid. We have revealed general trends in the distribution of macrocomponents between the precipitate and solution and demonstrated the feasibility of proportional tellurium(IV) and tungsten(VI) precipitation in the pH range from 2 to 7.

We have prepared (TeO2)0.80(MoO3)0.20 glass samples containing 0.01 to 0.11 wt % chromium and determined their optical transmission in the range from 450 to 2800 nm. The glasses have been shown to have a strong absorption band centered at 660 nm. From the attenuation coefficient as a function of Cr3+ concentration in the glasses, we have evaluated their specific absorption coefficient, which has been shown to be 190 ± 2 cm–1/wt % at the maximum of the absorption band.

Precipitates of tellurium(IV), molybdenum(VI), and bismuth(III) compounds of controlled composition have been obtained by precipitation from hydrochloric acid solutions of tellurium dioxide, ammonium heptamolybdate, and dibismuth trioxide. We have examined the general aspects of the macrocomponent distribution between the precipitate and solution and found conditions of a sufficiently complete tellurium(IV), molybdenum(VI), and bismuth(III) precipitation in a weakly acidic medium. After drying and calcination, the precipitates thus obtained were used as starting mixtures for the preparation of TeO2-MoO3-Bi2O3 glasses.

Molybdate-tellurite glasses have been prepared from precipitates obtained by adding aqueous ammonia to hydrochloric acid solutions of tellurium(IV) and molybdenum(VI) compounds. The impurity compositions of the precipitates and glasses have been determined by atomic emission spectroscopy. The results indicate that contamination with metal impurities occurs mainly in the precipitate washing step. Prolonged holding of a glass-forming melt in a porcelain crucible leads to contamination of the glass with aluminum, magnesium, and calcium.

We report the preparation of mixtures of tellurium and molybdenum oxides of controlled composition through the precipitation of tellurous and molybdic acids from hydrochloric acid solutions of tellurium(IV) and molybdenum(VI) compounds. We have established general trends in the distribution of macrocomponents between the precipitate and solution and shown the feasibility of quantitative tellurium(IV) and molybdenum(VI) precipitation in a weakly acidic medium. After drying and calcination, the precipitates were tested as TeO2-MoO3 glass batches.