[en] The ubiquitous hazardous and radioactive waste problems at US Government facilities - especially US Department of Energy (DOE) nuclear weapons plants - raise difficult technical, legal, and public relations issues. Because contamination problems are so widespread and complex, it is impossible for the government to reassure the public effectively that the situation is under control. Moreover, continued embarrassing public disclosures about the scope and potential health effects of contamination are inevitable. Under these circumstances, there are understandable temptations to downplay problems - and take other steps to avoid negative publicity - in order to buy time for development and implementation of technical solutions. If, however, DOE and other federal agencies are to regain public trust, they must avoid this temptation and approach their environmental problems with candor even at the cost of fostering public criticism and lawsuits

[en] Within models involving an extended gauge sector, a method is proposed for separating signals induced by new neutral gauge bosons and exotic leptons in electron-positron annihilation into a pair of W^± bosons. This method is based on use of polarization observables for various versions of initial and final polarization states. It is shown that, in the case of specified final polarization states, experiments with longitudinally polarized e⁺e^- beams at next-generation colliders will make it possible not only to obtain constraints on individual parameters of mixing of ordinary and exotic leptons, as well as on the angle of Z-Z' mixing, but also to toughen considerably the constraints that are expected from the corresponding experiments with unpolarized particles

[en] In a short introduction tests and calculations about CO₂-ice-blocs in the deep sea,use of CO₂ for underground-coal-gasifications and tertiary processes to increase oil-production by CO₂-flooding are shown. New activities are presented e. g. CO₂-injection into EAF combined with injection of coal, coke or direct reduction-fines. After research of injection of coals, fine ores or dust into blast furnaces and other shaft furnaces activities are compared with injection of hot reducing gas generated by coal or waste gasification or top gas recycling combined with injection of fine solid fuels. Results of injection of prepared plastics (Duales System Deutschland), shredder-light-fraction from car-recycling and unburned carbon of power-station-ashes are discussed. Beside production of direct-reduced-iron by H₂ fluidized reactor results of the reduction behaviour ore/coal or dust/coal pellets or briquettes for the use in rotary hearth or modern shaft furnaces are shown. (Author) 76 refs

[en] Injection rate of fossil fuels is limited because of drop in the flame temperature in the raceway and problems in the deadman region and the cohesive zone. The next step for obtaining a considerable coke saving, a better operation in the deadman as an well as increase in blast furnace productivity and minimizing the environmental impact due to a decrease in carbon dioxide emission would be injection by tuyeres of hot reducing gases (HRG) which are produced by low grade coal gasification or top gas regenerating. Use of HRG in combination with high pulverized coal injection PCI rate and oxygen enrichment in the blast could allow to keep and to increase the competitiveness of the blast furnace process. Calculations using a mathematical model show that the HRG injection in combination with pulverized coal (PC) and enriching blast with oxygen can provide an increase in PC rate up to 300-400 kg/tHM and a rise in the furnace productivity by 40-50% Blast furnace operation with full oxygen blast (100 % of process oxygen with the exception for the hot blast) is possible when HRG is injected. (Author) 54 refs

[en] Parts based on iron and steel powders are widely used in the manufacture of automobile and domestic equipment. This work was done to study the anti-friction properties of iron-pig iron-brass compositions of materials which were obtained by pressing and sintering from a mix of iron powders and industrial by products of cast-iron turnings, brass, talc and technical sulphur. Experiments were performed using cold pressure technology in the flowing matrix of the powder composite without solid lubricants. The subsequent sintering was carried out at 1200 degree centigree under isothermal conditions in a nitrogen atmosphere in the sintering zone during 1 h. The physical-mechanical and anti-friction properties were almost double by the active drainage of the gases from the compression mould. The study of the microstructure of the sintered materials showed that free cementite existed between the particle limits and around the pores. large agglomerations of dark inclusions could be observed, consisting of graphite, zinc and iron oxides, which were points of tension in the materials that reduce its durability and, therefore, its wear resistance to dry friction. (Author) 34 refs

[en] We study the spontaneous emission of a multilevel equidistant excited quantum oscillator (nuclei, atoms, molecules) in case when the symmetry of the dynamical transitions between the levels is described by the SU(1,1) symmetry group. The results obtained are compared with those well-known for the SU(2) symmetry. It is shown that the equidistant radiator in the process of spontaneous decay in case of SU(1,1) symmetry exhibits either only acceleration or only a decrease of spontaneous emission rates, while in case of SU(2) symmetry the radiation pulse is similar to that for the Dicke superradiance. The exact steady-state solution for the atomic density operator for an equidistant radiator driven by a totally incoherent broad-band (chaotic) field for SU(1,1) symmetry group is obtained using the Fokker-Planck equation. It is found that for a strong field limit in case of SU(1,1) symmetry the fluctuations in the atomic population increase with the increasing of intensity of the external field and don not achieve their maximal value as in case of SU(2) symmetry. Moreover, in case of SU(1,1) transition symmetry we found that there is a superbunching effect for certain values of group parameter I, while in case of SU(2) symmetry only bunching and antibunching occur. It is found that for vanishing values of the external field intensity the second-order intensity correlation function has negative values. (authors)

[en] The incessant increase of the competitivity of the metallurgical industry implies the necessity of the optimization of the resources and raw materials used. This affects in the same way the iron making in blast furnace and its principal fuel, metallurgical coke. It is from here the importance of the development of the techniques which facilitate improvements in the operation parameters in the blast furnace. This article is dedicated to the latest developments applicated on blast furnace process in the countries of European Community. (Author) 24 refs

[en] The liquidation of serious consequences of Chernobyl accident, taking into consideration their character and scale, requires the huge material and human resources. The complexity and plural of factors, affecting on planning and management of measures on medical-sanitarian maintenance of damaged population, requires the processing during acceptance of decisions, large files of information, containing parameters of healths condition of damaged population, information about the level of complex medical-sanitarian maintenance, dynamics of investments and compensation and etc. The instability of economic situation in Ukraine, connected with transition to new forms of managing and formation of political system does not permit to increase the resources on decisions the problems of liquidation of Chernobyl accident, requires the increasing the effectiveness, efficiency and qualities of accepted decisions on control and management of forming situation. (author)

[en] The injection of non fuel materials (iron ores, flux s, slags, ilmenite sands), siderurgical wastes, plastics, and others, both in single form and in mixture with pulverized coal, is analyzed. As the characteristics of the injected materials, variations in the operation of blast furnace can be introduced. (Author) 47 refs

[en] The technology of iron making with coal injection by tuyeres in the blast furnace is described. The influence of the main coal constituents in the furnace operation is analyzed. Information about the countries that employ this technology is given. (Author) 106 refs