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This paper presents the results of thermoradiation modification of nanostructure of potash-aluminum-boron glasses with iron oxide additives studied by optical spectroscopy. The differential spectra of the glass samples have jumps at 240, 320 and 370 nm. The physical mechanism of their formation is suggested. The obtained results show the way for the nanostructure modification useful for magneto-optical and dosimetric applications of the glasses. Valence-coordination transition of iron ions induced by irradiation at elevated temperatures can be used as switching effect in quantum computers.

Plastic scintillators are often used as detectors in High Energy Physics (HEP), but have insufficient radiation hardness. Organization of better light collection inside a single detector may prolong operation life of scintillators. A finger-strip plastic scintillator option has many advantages to keep the excellent detector performance at high luminosity. Measurements assigned to show an advantage of a stripped detector vs. the un-stripped one in the range of increased absorbed doses and the smallest dose rates have been performed. This method has proved to be a good upgrade strategy.

Recombination 60 Co-gamma-luminescence (GL) was studied experimentally in LiF:K,Cu crystals at the dose rate 406 R/s in the temperature range 273–473 K, when localized charge carriers are released from the hole/electron color center traps and Li vacancies are highly mobile. The crystals were preliminary irradiated in the 60 Co gamma-source at 300–320 K to doses 10 7 , 10 8 , 10 9 R to generate F -aggregate centers and nano-colloids of Li. The intensity of GL bands at 570 nm ( F 4 centers) and 670 nm ( F 2 + centers) was shown to increase after 10 6 R above 370 K due to dominant contribution from radiative recombination of the released carries at the interface of nanometal-Li–dielectric-LiF. These bands can be used for gamma-dose measurements at 10 7 –10 8 R.

Optical spectroscopy and X-ray diffraction techniques were used for studying nanoscale particles grown in pure SiO 2 glass under irradiation with fast neutron fluencies within 6×10 16 –5·10 19 cm −2 and gamma-quanta ~1.8×10 20 cm −2 in the reactor core in water. The neutron irradiation results in destroying of the initial α- and β-quartz mesoscopic order of 1.7 and 1.2 nm sizes and growing of cristobalite and tridymite nanocrystals of 16 and 8 nm sizes in the thermal peaks of displacements reapectively. The point defects (oxygen deficient E′ s , E' 1 , E' 2 and non-bridging oxygen centers) induced by the γ-irradiation are accumulated in the nanocrystals shell of 0.65–0.85 nm thickness. Interaction of close point defects at the nanocrystal–glass interface causes the splitting of optical absorption bands into the intensive ( D ~2–4) resonances characteristic for local interband electron transitions, having the width of 10–15 nm close to the nanocrystals' sizes and the energy depending on their structure.

Optical absorption, photo-excitation and photo- and gamma-luminescence spectra of nominally pure LuAG crystal and praseodymium doped LuAG:Pr scintillation detector were compared prior and after irradiations with 60Co gamma-quanta in the dose interval 102–106 Gy and reactor fast neutron fluencies 1016 and 1017 cm−2 accompanied by gamma radiation. The optical absorption of LuAG:Pr does not exceed 1 cm−1 in the range of 2.06–4.3 eV within the used gamma-dose interval. The gamma-luminescence of Pr3+ activator at 4.0 eV decreases by ~9% due to reabsorption by Cr4+ and is stable within 103–106 Gy. Fast neutron and gamma fluxes generate Frenkel pairs by elastic and inelastic mechanisms. Electron F- and F+-centers, hole O− centers, and also impurity Fe3+ centers suppress by 50% the Pr3+ emission by means of reabsorption after neutron fluency 1016 cm−2. The LuAG:Pr crystals can be recommended as a scintillator detector for applications involving neutron and gamma radiations at gamma-dose up to 106 Gy and fast neutron fluencies up to 1012 cm−2.

Pure quartz glasses of KS-4V and KU-1 types are candidates for optical plasma diagnostic system in ITER. The purpose of experiment was to study the efficiency of defect production in these glasses under irradiation with 60 Со γ -quanta (5.7 Gy/s) dose range of 10 2 –10 7 Gy and the fission reactor neutrons in the fluency range of 10 20 –10 23 n/m 2 and gammas simulating the plasma influence. In KU-1 (1000 ppm OH) the accumulation kinetics of E ′-(5.75 eV) and NBO-(1.9 eV) centers at γ - doses ⩾ 5 × 10 5 Gy and neutron fluencies 21 n/m 2 is faster, than that in KS-4V glasses ( 10 21 n/m 2 the NBO accumulation kinetics is slower in KU-1 than in KS-4B, because highly mobile hydrogen atoms access to the generated NBO centers. In KS-4V irradiated to γ -doses10 2 –5 × 10 3 Gy a new unstable absorption band at 1.8 eV was found, which is caused by the glass synthesis conditions and alkali metal impurities. The transparency at 3.5–6.2 eV at fluencies 10 20 –5 × 10 21 n/m 2 is higher in KS-4V than KU-1. However at fluencies >10 21 n/m 2 in KS-4V the photoluminescence band at 2.7 eV is more intensive and distorts a diagnosed signal. The transparency in 3.5–1.2 eV at fluencies >10 21 n/m 2 is higher in KU-1 than KS-4V.

The systems registering plasma radiation comprise optical elements, which may distort a diagnostic signal if they are not radiation resistant. The work was aimed at experimental study of optical absorption and γ-induced luminescence of KU-1 quartz glass and sapphire crystals in the range of 200–900 nm, which were irradiated in the 60 Co γ-ray source of 6.7 Gy s −1 up to the dose of 10 8 Gy and in the water cooled nuclear reactor of WWR-SM type with neutron fluences of 10 17 –10 20 cm −2 , in order to imitate plasma effect. The transparency window (minimal optical losses) and the intrinsic luminescence bands were determined in the studied materials. The advantages of KU-1 type glass over sapphire as optical elements at 300–350 K have been demonstrated.

This paper focuses on a narrow aspect of the demographic and health crisis in the former Soviet Union, examining the extent to which maternal behavior can compensate for poverty and poor medical conditions. Using sister hospital data form Bishkek, Kyrgyzstan and Kansas City, USA covering nearly 1,500 live births, the paper finds that Kyrgyzstani women are partially successful in compensating by taking better care of themselves and their newborn children. Moreover, ethnicity within Kyrgyzstan has no apparent impact on maternal behavior. Careful behavior, however, does not remove all disadvantages, and targeted interventions are still greatly needed.

Influence of γ-irradiation at the temperatures of 200–700°C on oxygen distribution and stability of YBa 2 Cu 3 O 7− x ceramics was studied by the neutron diffraction (ND), X-ray diffraction (XD) and electrophysical techniques. The equilibrium content and distribution of oxygen in sample volume, establishing after annealing for 3 h in air and being measured by the ND, was shown to change equally both in γ-ray field and out of it. After γ-irradiation at 400°C for 3 h tracks of BaCO 3 and CuO phases were detected on the sample surface by the XD analysis. These phases were caused by degradation of surface layer and therefore lead to increasing of the normal resistivity and to widening of the superconductive transition.