No abstract available

[en] Extraction systems containing zinc(2), a tetrazolium salt and an organic solvent were studied. Parameters characterizing solvent extraction equilibria and aqueous phase equilibria for the ion pairs were estimated. A technique of quantitative analysis of superpure metallic cadmium for zinc impurity was developed on the basis of solvent extraction and photometric determination

No abstract available

[en] The optimum conditions for extraction of niobium(V) as a ternary ion-association complex with pyrocatechol and triphenyltetrazolium chloride (TTC) have been determined. The investigation of the composition has shown that the ratio Nb:pyrocatechol:TTC is 1:2:1. Ksub(ex), Ksub(D) and β have been determined radiometrically, using the chemical model. The influence of foreign ions on the extraction of the ion-association complex has been studied. A method for artificial mixture and steel containing niobium has been used. (author)

[en] The radio-sensitivity of Picea abies (L.) Karst populations was investigated by comparing the effect of acute irradiation with different Co-60 rates on seed germination and the survival of the seedlings obtained from them. Spruce stands in the Rila, Pirin and Rhodopes, the Balkan, Vitosha and Ossogovo mountains have been studied at 1000 to 2000 m alt. into 200-300 m intervals. The seed material collected from them by individual trees, altitude belts and mountains has been irradiated with 200 krad, 500 krad, 1000 krad, 1500 krad and 7500 krad. The germination capacity of the seeds was calculated in technical germination, absolute germination, germination energy and seed dormancy, while the post-irradiation effect was established in accordance with the survival rate of the seedlings for one- and two-year periods in greenhouses on a sand substrate. Radio-sensitivity of every spruce population depended on its vitality and Vigour. The spruce population in the Rhodope Mountains exhibits highest radio-hardiness, followed by those in the Rila, Central Balkan, Pirin, Vitosha and Ossogovo mountains. Irradiation with 200 krad, and in certain cases with 500 krad, showed a stimulation effect on germination of spruce seeds and the survival rate of the seedlings. LD-50 for spruce seeds, taking into account one- and two-year-old seedlings, was within the 500 to 1000 krad range. (author)

[en] A program simulator for the M 6800 microprocessor system is described. The device is intended for simulating microprocessor instructions, CAMAC commands, commands of an program-interrupting system, etc. The simulator is built as a program translator with a packet of subprograms in the PL/1 algorithmic language for ES computers. It provides for considerably easier check-out of programs for M 6800, particularly when the nature of the object does not permit to check-out the program by direct coupling of this object with the microprocessor

[en] The M6800 microprocessor system for controlling a CAMAC interface is described. Data input is realized into A, B and X registers of the microprocessor, not into the main memory. This permits to avoid double reference to the memory and to substantially decrease the number of electronic components. The system flowsheet contains the M6800 microprocessor, a main memory, peripheral adapters, and teletype communication circuit. The system occupies three or four stations in the CAMAC standard and permits to control 22 modules

[en] The possibility is studied of attenuating the feedback wave in electron-beam-based Cherenkov microwave oscillators at the expense of its resonant interaction with the beam cyclotron wave under normal Doppler effect conditions. Oscillators operating in the regimes of the collective and single-particle stimulated Cherenkov effects are considered. Stability conditions for a system with a beam that is subject to the Cherenkov and cyclotron resonances at the emission frequency are found. Applications to particular problems in plasma microwave electronics are discussed

[en] The Spallation Neutron Source, a neutron scattering user facility based on a 1.4 MW proton accelerator, has been in operation since 2006. The accelerator beam diagnostics were designed, in large degree, with commissioning unknowns in mind. Today we face new challenges to support stable 1 MW beam power operations and an accelerator upgrade for even higher power. The beam instrumentation problems span a range from mitigating obsolescence of many electronics to developing new techniques for measuring beam parameters important for high power operation. This report describes several examples of the ongoing work: development of new electronics for the Beam Position Monitor (BPM) and Beam Loss Monitor (BLM) systems to replace the aging designs; and development of large dynamic range and high precision beam phase space characterization tools to facilitate model based accelerator tuning. (author)

[en] Considering that corrosion takes place as a random process over time, a a probabilistic approach was utilized in this paper. The corrosion of metallic sheet piling employed in the fascia wall of a bulwerk is considered as an example. A stochastic model is constructed on the base of a modified Weibull distribution function with consideration of parameters of the corrosion process as a function of time. One of the factors defining the corrosion rate of the sheet piling is the degree of access of a section of the wall to the zone of variable water level, or the underwater zone. The type of corrosion—continuous or local—is another factor. The accuracy of corrosion prediction in the underwater zone is higher than that in the zone of variable water level.