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BACKGROUND: The subject of the study is the technological process of spraying field crops with slotted sprayers and the indicators dispersion. AIMS: Improving the technological process of spraying plants with the use of pneumo-hydraulic slotted sprayers. METHODS: Special equipment was used for photographing films of the liquid being sprayed under various operating modes of slotted sprayers with the possibility of calculating the size of the droplets. Fulfillment of the requirements for the number of drops/cm2 at the treated object, overlapping the liquid spray jets ensures uniform distribution of drops over the spraying width. Therefore, it was sufficient to have information about the fragmentation of the thickness of the liquid film along the axis of the nozzle spray liquid into drops and obtaining their quantity per unit time depending on the flow rate of the working fluid. Newness of the research lies in determining the effective operation of slotted sprayers as part of the spraying device. RESULTS: With the use of the special equipment, it is possible to fulfill agrotechnical requirements for droplet sizes. When using herbicides for foliar post-emergence treatment with a systemic pesticide, the limits of MMD range are from 226 m to 400 m. Soil herbicide treatment with a systemic pesticide requires an increased droplet MMD range of 401 m to 500 m and 500 m. The number of drops/cm2 when using fungicides is limited from 50 to 70, insecticides from 20 to 30, and herbicides from 20 to 40. CONCLUSIONS: The applied technology makes it possible to reduce the consumption of preparations and working fluid with high work performance and resource saving. The above research results can be used as the basis for determining the effective technology of a boom sprayer with slotted liquid sprayers. Fulfillment of the requirements for the number of drops/cm2 at the treatment facility overlapping liquid spray torches ensures a uniform distribution of drops over the spraying width. Therefore, it suffices to know about the division of the thickness of the liquid film along the axis of the liquid spray jet into drops and to obtain their number per unit time.

In the article the results of the eccentrically compressed reinforced concrete element calculation operating under the dynamic loading in fire conditions are shown. The calculation of the compressed reinforced concrete element was carried out, taking into account the conducted experimental studies. The calculation showed that, depending on the temperature effects, the curvature of the reinforced concrete element in stages I and II decreases while the class concrete, which varies from 28.9% to 55%, is increasing. When the temperature reaches 2500, the cracking moment and the moment of internal forces at the end of the stage II are reduced to 22% with respect to these forces at normal conditions. With increasing temperature, the dynamic stiffness of the element in the stage I is reduced by 29.3%.

Plastic scintillators are often used as detectors in High Energy Physics (HEP), but have insufficient radiation hardness. Organization of better light collection inside a single detector may prolong operation life of scintillators. A finger-strip plastic scintillator option has many advantages to keep the excellent detector performance at high luminosity. Measurements assigned to show an advantage of a stripped detector vs. the un-stripped one in the range of increased absorbed doses and the smallest dose rates have been performed. This method has proved to be a good upgrade strategy.

A new K L 0 and muon detector based on scintillators will be used for the endcap regions in the Belle II experiment, currently under construction. The increased luminosity of the e + e − SuperKEKB collider entails challenging detector requirements. We demonstrate that relatively inexpensive polystyrene scintillator strips with wavelength shifting fibers ensure a sufficient light yield at the Silicon PhotoMultiplier (SiPM) photodetector, are robust and provide improved physics performance for the Belle II experiment compared to its predecessor, Belle.

Prospects for the observation of CP violation in B-meson decays are briefly reviewed based on the talk given at the Russian Academy of Sciences Presidium session of January 20, 1998.

Results on the light output of different kinds of silica fibres and on energy resolution and electromagnetic shower dimensions in small lead/quartz fibres calorimeter prototypes are presented, together with a possible design of a very forward calorimeter for LHC.

High-pT trigger at HERA-B experiment could be used to make fast selection of B → π+ π−, B → K+ π− and other important decay modes. The trigger includes three layers of gas pixel chambers and straw tubes with cathode pad readout. Various tests of hardware prototypes have been done. The off-line analysis simulation shows that acceptable signal to background ratio could be achieved.

A small quartz fiber calorimeter prototype with copper absorber has been assembled and tested at ITEP as a first test of a “0 degree” component of the RD-40 R&D program. Calibration and monitoring of each tower response was performed using the positions of single photoelectron peaks as well as the response to minimum ionizing particles incident at an angle of 45°. The response of the prototype to 4 GeV electrons as a function of beam angle with respect to the quartz fibers was studied in the range from 0° to 90°. The test results are compared to the GEANT based Monte Carlo (MC) simulations.

The celebrations of the 275th anniversary of the Russian Academy of Sciences are taking place in Moscow from 31 May to 5 June 1999. Joint Jubilee Session of the Division of General Physics and Astronomy and the Division of Nuclear Physics of the Russian Academy of Sciences (RAS) was held at the P N Lebedev Physics Institute, RAS on 1 June 1999. The following talks will be presented: (1) Andreev A F 'Mesoscopic superconductivity in superspace'; (2) Rubakov V A 'Particle physics and cosmology: current status and anticipation'; (3) Gaponov-Grekhov A V, Luchinin A G and Talanov V I 'Physical foundations of remote-control probing of the ocean'; (4) Alferov Zh I 'Quantum-dimensional nanostructures'; (5) Boyarchuk A A 'Binary stars'; (6) Danilov MV 'Current status and prospects in elementary particle physics (experimenter's outlook'). Papers based on these talks will be published in a special jubilee issue of Physics-Uspekhi.

A new type of wall-less gas wire chambers with a pad-type readout, called gas pixel chambers, has been designed, built and successfully operated in the HERA-B experiment. The pixel chambers were used as an inner part of a High-p/sub T/ system, a pretrigger on hadrons with high transverse momenta. The cell sizes in the chambers varied from 4/spl times/8mm/sup 2/ to 10.31/spl times/10.31mm/sup 2/. The chambers collected signals within 96nsec, the bunch separation in HERA. The chambers could operate in a hard radiation environment with particle fluxes up to 10/sup 6//cm/sup 2//s. The amount of material was only 0.9% of radiation length per chamber including support frames. The readout electronics was placed outside of the acceptance and the signals were brought there by very thin twisted pair cables with a wire diameter of 50/spl mu/m. The system consisted of 12,000 channels. A similar type of chambers but with larger amount of material was used also in the inner part of the HERA-B muon system. Design of the chambers, performance and experience of operation are described.

A review is given of experimental data on oscillations. Basic theoretical concepts are discussed and an analogy with oscillations is noted. A detailed analysis is given of experimental searchesfor oscillations with particular attention devoted to the ARGUS data, which reveal mixing with r = Γ( → → X')/Γ( → X) = 0.21±0.08. The consequences of large mixing are examined and future studies of the properties of the b quark are discussed.