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The article explains the Russian model of social orphanhood eradicating based on the analysis of the dynamics of the adoption and foster care and social orphanhood prevention, the legislation development and a compari- son with the international experience. The effectiveness of the state policy is depends on focus of the top federal and regional officials, the dynamic legis- lative development, federal financial support and creative accomplishing the tasks of social orphanhood eradicating throughout the country. Author proposes methodology for evaluating the regions performance based on math- ematical models of the continuity equation. The article identifies a number of factors determine the features of the state policy implementation throughout Russia, including ethnic and religious factors, geographical proximity to the international experience, migration flows, climatic conditions, and the health level. It is pointed out that the implementation of the National Strategy for Action on Children plays a key role in forming the Russian model. The main modern challengers are defining the strategy and tactics of the family and foster care of children difficult to place in family, services on interdepartmental basis, and economic crisis, which may lead to an increasing return of children from foster families.

Experimental results on the production and separation of 149Tb from natural neodymium target using the nuclear process Nd(12C,xn)149Dy→149Tb are presented. Terbium-149 was produced at the U-200 cyclotron of FLNR JINR by irradiating natNd2O3 with 12C ions and its possible production for nuclear medicine utilising the heavy-ion induced reactions was investigated.

A short review of the radiochemical methods for preparation of widely used or promising cyclotronproduced radionuclides for nuclear medicine and biomedical or environmental studies is given. The presented data include the current status of the production of some gamma-emitters (97Ru, 111In, 123I, 201Tl), generator-pairs (68Ge/68Ga, 82Sr/82Rb, 128Ba/128Cs, 178W/178Ta), radioisotopes for metabolism studies (26Al, 67Cu, 237Pu) and actinides tracers for environmental researches (235Np, 236Np, 236Pu). The conditions for preparation of high-purity isotopes have been investigated and procedures including target chemistry design were developed.

The work on isotopically pure 26 Al, 97 Ru, 178 W/ 178 Ta, 235 Np, 236 Pu and 237 Pu production was initiated because of intensive research on their applications in the biomedical field and environmental chemistry. The conditions for isotopically pure production have been investigated. This paper describes the data for the nuclear reactions of the radionuclide production, the different target designs and target chemistry procedures.

Summary A short review of recent data concerning development of production methods of some radioisotopes at FLNR JINR (Dubna) is presented. Nuclear reactions, targets, yields and radiochemical separation procedures for production of highly-pure radionuclides are given.

The excitation function was measured using the stacked foil technique for the formation of [sup 44]Ti in proton induced reactions on a vanadium target over the energy range 54-100 MeV. The maximum cross section (0.66[+-]0.13) mb was observed at (79[+-]2) MeV. The error was estimated to be [+-]20%. The experimental results are compared with theoretical calculations based on the hybrid model of nuclear reactions using the computer code Overlaid Alice. The calculated values are consistently higher than the experimental data. The production yield of [sup 44]Ti was estimated from the excitation function to be 0.015 [mu]Ci/[mu]Ah (540 Bq/[mu]Ah) for a 7.7 g/cm[sup 2] thick vanadium target with a proton entrance energy of 99.5 MeV and exit energy 53.4 MeV after an elapsed time of 1 year from EOB to allow for the decay of shorter lived radio-activities. (orig.)

Among radioactive isotopes of rare-earth elements (REEs) finding increasing application in nuclear medicine, α-emitting 149Tb (T1/2 = 4.118 h; EC 76.2%; β+ 7.1%; α 16.7%) shows promise for radioimmumotherapy. Formation of 149Tb in nuclear reactions Nd(12C, xn)149Dy(4.23 min; β+, EC) → 149Tb performed by irradiation of a Nd target with carbon ions was experimentally studied. As estimated from the experimental data on 149Dy formation and its decay into 149Tb, the 149Tb yield under the best conditions (142Nd-enriched target, 12C ions with the energy of up to 120 MeV and current of up to 100 μA, irradiation time 8-10 h) can be as high as 30 GBq (0.8 Ci).

Radiochemical methods of thallium-201 separation from proton-irradiated thallium, lead and bismuth targets have been developed. The procedures are based on the processes of coprecipitation, ion-exchange chromatography and high temperature gas chemistry. The purity of thallium samples complies with requirements of nuclear medicine for thallium-201 product.

A sorption technique is developed for radiochemical separation of thallium-201 from proton-irradiated targets of metallic thallium. The technique consists in separation of 201Pb with the PbSO4 precipitate followed by separation of 201Pb and 201Tl in the column with ammonium 12-molybdophosphate fixed in the matrix of porous Teflon (AMP-sorbent). The chemical yield of radiothalium is 98%, the duration of chemical procedures is 2.5 … 3 hours.

Excitation function for the 113Cd(p,3n)111In and 114Cd(p,4n)111In reactions were measured by the stacked-foil technique in the energy range from 63 to 3 MeV. The results were compared with theoretical calculations based on the hydrid model using the well developed computer code ALICE. For the same energy range, the effective cross-sections were determined for the natCd(p,xn)111In reactions. At the initial proton energy of 63 MeV for production of 111In from 113Cd, 114Cd and natCd the cumulative yields were found as 16.7, 15.7 and 10.4 mCi/μ Ah respectively. The contamination of the undesired nuclide 114mIn was determined. The no carrier added (NCA) 111In was separated from the cadmium cyclotron-target by a procedure based on ion exchange chemistry. The radionuclidic purity of the final radioindium was determined.

A short review of the current data concerning nuclear reactions, target chemistry and following applications of some radioisotopes as tracers is given in this report.

Proton-induced reactions on 99Tc target were studied in order to evaluate the 99Tc(p,3n)97Ru reaction as a source of high radionuclidic purity 99Ru. Measurements of excitation functions for the main reaction 99Tc(p,3n)97Ru and competmg 99Tc(p,pxn)99m,96,95Tc reactions were performed in a stacked-foil experiment using gamma spectrometry. The maximum cross section for 97Ru formation in the first reaction was found to be 440 mb (±15%) at 32 MeV. Results are compared With calculations based on the hybrid model of nuclear reactions (Overlaid Alice and Alice 85/300). For the proton energy range 99 – 20 MeV the cumulative 97Ru yield of 10.5 mCi/μA·h was estimated.

Cross sections and yields have been determined for some radionuclides, frequently used in nuclear medicine (52Fe, 77Kr/77Br, 82Sr, 123Xe/123I, 128Ba, 201Tl), by bombardment of natural and enriched targets with protons of energy ≤ 100 MeV. The experimental cross sections are compared with the excitation functions calculated by the code Overlaid ALICE in the energy range from the thresholds up to 100 MeV. At the end of bombardment the thick target yields were as follows (mCi/μA·h, in the selected energy range): for 52Fe from 55Mn — 0.8 (36–100 MeV) and from 59Co — 0.1 (64–100 MeV); 77Kr from 79,81Br — 313 (24–100 MeV); 82Sr from 85,87Rb — 0.43 (36–100 MeV); 123Xe from 127I — 270 (48–100 MeV); 128Ba from 133Cs — 8.4 (43–100 MeV); and for 201Tl from: 206Pb — 3.5 (48–57 MeV), 207Pb — 3.0 (57–68 MeV), 208Pb — 1.5 (68–76 MeV) 32 hours at the end of the bombardment.

Absorption of carrier-free T1 from nitric acid solutions of lead by ammonium 12-molybdophosphate fixed in the matrix of porous Teflon (AMP-sorbent) has been investigated. Effective separation of T1 and Pb is shown to take place. Elution processes of T1 from AMP-sorbent have been investigated. It is found that complete extraction of T1 is achieved upon dissolving AMP in concentrated ammonia. Further purification and concentration of T1 are performed by means of cation exchange chromatography on Dowex-50 or KU-2 resins. Investigation of high temperature behaviour of T1 ultramicroamounts in Pb melt showed that T1 is quantitatively separated out into the gas phase when fluorinating additions of PbF2 or NaF solid salts covering the melt surface are used. The volatile compounds of radiothallium formed were transported by a stream of inert gas (He or N2) from the evaporation zone to the thermochromatographic column, where they were sorbed on the surface in a limited zone with the maximum at ∼240 °C. Liquid and gas thermochromatographic methods for separation of carrier free radiothallium from protonirradiated lead material have been developed. The radiochemical, chemical and radionuclidic purity of T1 samples complies with requirements of nuclear medicine for201T1 product. Both methods ensure ∼95% chemical yield of T1 and take about two hours each.

A diagrammatic lay-out of the facility for the on-line radioiodine (123Xe) by CsCl irradiation on the LNP JINR synchrocyclotron is presented. The problems in designing the target, collection systems and radioxenon transport are considered. The described experimental arrangement is a model for future 123I production on the “F”-facility (JINR high-current accelerator).

Conditions of the 123I production from 123Xe, formed by irradiating thick targets with 660 MeV protons, are studied. The cross section of the 122Xe, 123Xe and 125Xe production have been determined in I, Cs, Ba and La targets for Ep = 660 MeV. 123I yield and the contamination by 121I, 125I, 121Te and 119Te at irradiation of the CsCl melt (54g/cm2) and the on-line Xe separation, have been determined by calculation and experimental methods.

Volatilization of ultramicroamounts of spallogenic products (Mo, Tc, Ru, Re and Os) from the melts of irradiated Ag and Au metals under dynamic vacuum conditions at 10−3–10−2 torr O2 and H2O vapours and their separation in a thermochromatographic column are studied. The influence of the time of sublimation, the gas phase parameters and the materials of the crucible and the column are investigated. Possible reactions and chemical forms of volatile spallogenic products are discussed. Diffusion coefficients are defined for an Ag-melt case. The conditions of Re/Os and Mo/Tc/Ru separation are found. The possibility of using the Ag and Au melts in the ISOL-system is considered.

Diffusion of the ultramicro amounts of elements, obtained by irradiation with 660 MeV protons in silver, has been studied in molten silver at 1080±20°C. Concentration distribution of the elements has been determined by a fractional layer dissolution method. Diffusion coefficients, the knowledge of which seems to be important for “on-line” isotope production, have been determined by means of relationships obtained from the theoretical evaluation of the processes.