[en] The report describes the remote technologies employed in the nuclear power plant with RBMK-1000 type. Spent fuel transfer and handling operations at reactor (AR) and away from reactor (AFR) on reactor site (RS) facilities are illustrated by the example of the Leningradskaya NPP and are typical for all NPPs with RBMK-1000. The current approach to spent fuel management at NPP sites is also presented. (author)

[en] A few attempts were conducted to establish basic needs, materials, conditions and procedures for artificial rearing of Anastrepha fraterculus, henceforth AF. A brief summary will be presented based on published and personal information. (author)

[en] Full text: In 1916, Rust recorded Anastrepha fraterculus, the ''South American fruit fly (SAFF)'', in Tucuman. Since 1910, the citrus area in the province has increased rapidly and SAFF has become an important pest. New varieties and management practices were also introduced in the region. Guavas (Psidium guajava) and peaches (Prunus persica) were the main host fruits of SAFF in Tucuman, but cherimoya (Anona chirimoya) and apricots (Prunus armeniaca) were also important. After the beginning of rains, populations increase in spring and develop mainly on peaches in November and December. Afterwards, SAFF attacks guava, where a peak population is attained in February or March. Guava is the principal wild host of SAFF in Tucuman. Compared with the forest where guava trees were frequent, citrus orchards covered a small area in the 1920's. Therefore SAFF populations increased in the wild guavas and invaded early oranges and grapefruits afterwards. Even though high numbers of punctures were observed in citrus skin, few larvae developed. The oils present in the skin kill high number of eggs. Moreover the larvae have to go through the albedo and hardly reach the pulp. Nevertheless the injury produced by the ovipositor allows microorganisms to rot the fruit. In 1918, rots produced 50% of damage in fruits which suffered premature ripening and fell. Only in very thin skinned and overripened fruit, larval development was registered. Some authors observed larval development in the field but Schult, in laboratory tests, found few eggs and never registered larval development. Between 1920 and 1945 studies with bait-traps were carried out to establish the seasonal occurrence of the fly and some control measures were tested. Poisoned baits were used against this pest, and biological control by inoculation of parasitoids were also employed. Cages with parasitized pupae were distributed to farmers. The emerged flies were kept within the cage and a sieve allowed the emerged parasites to leave the cage and disperse. In March 1945, Ceratitis capitata was captured for the first time in traps. Since that event, insecticide sprays are increasingly used against this pest mainly in citrus orchards. In the fifties the ''citrus tristeza virus'' (CTV) wiped out all orange, grapefruit and tangerine orchards which were grafted on sour orange rootstock. They were replaced by lemons, the only tolerant species on sour orange. Some orange and grapefruit varieties were also grown on tolerant rootstocks. Between 1950 and 1975 new studies were carried out in order to establish the importance of C. capitata as a new pest. In 1952-53 trap catches show SAFF more abundant than medfly, when lemons were already the predominant species of citrus. In 1960-63 the number of grapefruits increased again and medfly became more abundant. Between 1960 and 1980, medflies were predominant in trap catches, probably because of the expansion of citrus orchards. No further studies of this species continued after 1980. It is not clear if medfly displaced SAFF by competition in citrus orchards, or if the expansion of the citrus area restricted SAFF to the forest where wild guavas and peaches are still present. The fact is that in my samplings of citrus fruits in Tucuman and other places like La Rioja province, I have never obtained specimens of SAFF. Several laboratory, semifield and field tests should be done in order to establish the current importance of SAFF in Tucuman. (author)

[en] This paper presents available (published) information on specific abiotic factors, such as temperature, humidity, and lighting on the life cycle of Anastrepha fraterculus, henceforth AF. AF displays holometabolous development: egg, larva (development is completed in three instars), pupa and free living adults. (author)

[en] Anastrepha fraterculus (Wied) is the most important fruit fly in Colombia. It has been trapped from the sea level up to 2000 m of altitude, but is is more abundant in the coffee growing area located at 1300 to 1700 masl, with temperatures between 18 to 22 deg. C (-min 11 deg. C,-max 25 deg. C). The main host in that area is Coffea arabica L., but it also has 14 additional identified hosts that belong to 9 families. In the hot climates from 0 to 1000 m of altitude it breeds in mango (Mangifera indica L.) and guava (Psidium guayava L:). The pest has not been stabilised in the cultivated upper lands between 2300-2600 masl. (author)

[en] Fundamental aspects of the selectivity of radiation-induced events in polymers and polymeric systems were considered: (1) The grounds of selectivity of the primary events were analyzed on the basis of the results of studies of model compounds (molecular aspect). Basic results were obtained for hydrocarbon molecules irradiated in low-temperature matrices. The effects of selective localization of the primary events on the radical formation were examined for several polymers irradiated at low and superlow temperatures (77 and 15 K). A remarkable correlation between the properties of prototype ionized molecules (radical cations) and selectivity of the primary bond rupture in the corresponding polymers were found for polyethylene, polystyrene and some other hydrocarbon polymers. The first direct indication of selective localization of primary events at conformational defects was obtained for oriented high-crystalline polyethylene irradiated at 15 K. The significance of dimeric ring association was proved for the radiation chemistry of polystyrene. Specific mechanisms of low-temperature radiation-induced degradation were also analyzed for polycarbonate and poly(alkylene terephthalates). (2) Specific features of the localization of primary radiation-induced events in microheterogeneous polymeric systems were investigated (microstructural aspect). It was found that the interphase processes played an important role in the radiation chemistry of such systems. The interphase electron migration may result in both positive and negative non-additive effects in the formation of radiolysis products. The effects of component diffusion and chemical reactions on the radiation-induced processes in microheterogeneous polymeric systems were studied with the example of polycarbonate - poly(alkylene terephthalate) blends. (3) The effects of restricted molecular motion on the development of the radiation-chemical processes in polymers were investigated (dynamic aspect). In particular, it was found that kinetics of radical decay was affected strongly by local molecular dynamics of polymeric chains in specific microphases. These features are especially important at low temperatures and for 'well-organized' polymeric systems, such as highly oriented and highly crystalline polymers or microheterogeneous bicomponent systems. The results obtained show that the radiation-induced chemical events in solid polymers are far more selective than it might be expected from formal energetic reasons. The localization of primary events is controlled by conformation, weak molecular interactions, and microstructure of polymeric system. Some important mechanisms of this selectivity could be understood taking into account the properties of prototype ionized molecules. Significance of the concept of 'selective radiation chemistry' for prediction and improvement of the radiation resistance of polymers and polymeric materials is discussed. (author)

[en] The Department of Research Reactor is responsible for the operation, maintenance, utilization and related R and D works of the research reactors including JRR-2, JRR-3M (new JRR-3) and JRR-4. This report describes the activities of the department in fiscal year of 1997 and it also includes some of the technical topics on the works mentioned above. As for the research reactors, we carried out the operation, maintenance, the utilization of irradiation and neutron beam experiments, technical management including fuels and water chemistry, radiation monitoring as related R and D works. The international cooperations between the developing countries and the department were also made concerning the operation, utilization and safety analysis for nuclear facilities. (author)

[en] The three-body break-up ⁶He→⁴He+n+n is studied experimentally, using a secondary ⁶He ion beam of 240 MeV/u incident on carbon and lead targets. Integrated cross sections for one- and two-neutron knock-out and differential cross sections dσ/dE^* and dσ/dθ for inelastic nuclear or electromagnetic excitations into the ⁶He continuum are presented. The E1-strength distribution is deduced from electromagnetic cross sections and is found to exhaust (10±2)% of the energy-weighted TRK sum rule or (40±8)% of the cluster sum rule for excitation energies below 5 MeV. Both the energy-weighted and non-energy-weighted dipole cluster sum rules are almost exhausted integrating the strength up to 10 MeV, a fact, from which a root-mean-square distance between the α core and the two valence neutrons of r_α-2n=(3.36±0.29) fm is derived. The known I^π=2⁺(1.80 MeV) resonance in ⁶He is observed in nuclear inelastic scattering; model dependent values of the quadrupole deformation parameter δ₂=(1.7 ± 0.3) fm or B(E2,0⁺→2⁺)=(3.2±0.6) e²fm⁴ are derived. No clear signature could be obtained for predicted higher-lying 2⁺ resonances, but low-lying continuum strength of multipolarity other than dipole, likely of monopole and quadrupole multipolarity, is indicated by the data. Two-body correlations in the decaying ⁴He+n+n system are investigated. The astrophysical relevance of the data with regard to the two-neutron capture process ⁴He(2n,γ)⁶He is briefly discussed. (orig.)

[en] Double ionisation of helium in the perturbative regime has been explored in a kinematically complete collision experiment using 100 MeV/u C⁶⁺ ions. Different ionisation mechanisms are identified by inspecting the angular distribution of the electrons as a function of the momentum transfer q to the target by the projectile. For q<1.2 a.u., both electrons are distributed uniformly in the plane perpendicular to the projectile axis, and distinct similarities with photoionisation are identified. For q>1.2 a.u., the faster electron resulting from a binary encounter with the projectile is emitted along the direction of momentum transfer, while the other electron is distributed uniformly. Experimental data are compared with various model calculations based on the Bethe-Born approximation with shake-off. Surprisingly, the effect of the final state interaction is found to depend decisively on the choice of the initial state wave function. (orig.)

[en] The paper describes nuclear fission reactor characteristics as neutron producers and their use with targets of molybdenum-98 and uranium-235 to produce ⁹⁹Mo. Tabulations of reactors used and their characteristics are shown. A new method for ⁹⁹Mo production using an aqueous homogenous reactor is described showing the potential for 1/100^th waste, uranium consumption and power level for a given quantity of ⁹⁹Mo. A graph is shown of the expected growth in ⁹⁹Mo use and world-wide costs. The use of low-enriched (less than 20% ²³⁵U) in the homogenous reactor system is possible. (author)