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The milestones in the development of the urea industry in Russia are briefly outlined in commemoration of the 150th anniversary of the Bazarov reaction. It is noted that due to the unique consumer properties of urea, the demand for it and the volume of production increases from year to year. Significant volumes of production and high unit capacities of urea production reactors require the use of energy- and resource-saving technologies, the implementation of which in industry necessitates the creation of new high-performance equipment. The R&D work on such equipment was carried out in several directions. (1) Development of internal devices for high-pressure urea synthesis reactors (cross-sectional and longitudinal sectioning, feed components mixers). The developed internal devices increase the efficiency of the synthesis and the degree of conversion of raw materials into the final product, as well as reduce the recycle to the synthesis reactor. This allows not only improvement of the energy efficiency of the production (reducing steam, power, and circulating water consumption), but also creates prerequisites for increasing the productivity of the reactor. (2) Application of film-type heat and mass exchangers for melt stripping and evaporation of urea solutions. (3) Design of plate-type heat and mass exchangers. The construction of a film-type evaporation equipment of special design allows much more efficient heat and mass exchange compared to "submerged" equipment. In addition, the radically shorter residence time of the urea solution in such apparatus favors a lower amount of the biuret by-product. The use of the plate-type equipment with mass-exchange plates of special design reduces metal consumption, increases the efficiency of all processes, and reduces drop entrainment from the distillation column. [ABSTRACT FROM AUTHOR]

The authors discuss the factors that facilitate or impede public participation in local policy formation and implementation. They analyze the roles played by nonprofit nongovernmental organizations. [ABSTRACT FROM AUTHOR]

Errors of measuring time dependences of the light intensities of picosecond laser pulses by two electron-optical systems are studied. The first system is the picosecond streak camera made in Russia, and the second system, designed in Germany, consists of a picosecond streak camera coupled with a double spec-trograph. The manufacturers test similar systems by using femtosecond pulses, however, this does not allow one to predict errors of measuring picosecond pulses. Parameters that characterize just these errors are proposed and measured. Their behavior is determined, when the amplitude (energy) of the measured pulses increases, and the influence of the cross-section shape of the light beam on the measurement accuracy is studied. [ABSTRACT FROM AUTHOR]

Characteristics of the Russian mineral-resource base and its development under the current market conditions are given on the basis of the analysis of deposits accounting for 90% of reserves and extraction of 65 types of mineral resources. Statistical data on reserves of the deposits included into the State Register and the demanded component of the mineral-resource base are presented. The defining role of major deposits in the mineral-resource base development is demonstrated. The group of highly liquid minerals forming the domestic mineral-resource base is described. The reserves of these mineral raw materials are essential and sufficient to satisfy both the domestic needs and a considerable export component. [ABSTRACT FROM AUTHOR]

In this article we describe the chromatographic separation of acid nuclear protein fractions which have previously been shown to be active in DNA transfection experiments. By combining anionic and cationic ion exchangers, we were able to separate and identify some of the active proteins. In addition to HMG1, already known for its transfection activity, we have identified histone H1 and HMG17 as further transfection-active proteins. The highest transfection activity was associated with H1 and another nonidentified protein showing a somewhat higher electrophoretic mobility than H1. We have also found that the presence of CaCl2 in a low concentration in the cell culture medium is an important requirement for transfection. [ABSTRACT FROM AUTHOR]

The article reports on the study supported by the Russian Foundation for Basic Research which determines chlorine (Cl)-bearing lizardite from metakimberlite of the Udachnaya in Northern Yakutia, Russia. It describes lizardite as the lowest temperature among serpentine-group minerals, whereas antigorite is the highest temperature. It notes the occurrence of the serpentinization of kimberlite in all platforms of the Earth, including the Eastern Siberian Platform. The study shows that nearly all serpentine in the studied samples from many kimberlite bodies of the Eastern Siberian Platform in lizardite.

Presents a biographical sketch of Vitalii Ivanovich Stafeev, a Russian scientist, professor and doctor of physical and mathematical sciences, on the occasion of his 70th birthday. Personal background; Academic profile; Scientific career; Contributions to science.