[en] This thesis presents inclusive e^±p single and double differential cross sections for neutral current deep inelastic scattering measured as functions of the four-momentum transfer squared Q² and the Bjorken variable x in interactions of longitudinally polarised leptons with unpolarised protons using the H1 detector at HERA II. An overview of the phenomenology of deep inelastic scattering is given and the experimental apparatus as well as the measurement and analysis procedures are described. The analysis is based on e⁺p data taken in 2003-04 and e^-p data taken in 2005 at a centre-of-mass energy of √(s)=318 GeV, with integrated luminosities of 47.6 pb^-1 and 98.4 pb^-1 for the e⁺p and e^-p samples, respectively. The cross sections are measured in the range of 200< Q²<20 000 GeV² and 0.0032< x<0.65. The measurements are used to study polarisation e ects in neutral current interactions and to determine the structure function xF₃. The new HERA II data are combined together with previously published data from HERA I to determine the structure function xF₃ with improved precision. Furthermore, this measurement is combined with the corresponding ZEUS measurement to provide the most accurate measurement of the interference structure function xF^γZ₃, which is sensitive to the valence quark distributions down to low values of x. The data on polarised cross section asymmetries A^± are also combined with the ZEUS data. This leads to the first observation of parity violation in neutral current e^±p scattering at distances down to 10^-18 m. The data are well described by the Standard Model predictions. (orig.)

No abstract available

[en] Blood samples from 243 clean-up workers who undertook duties at Chernobyl in 1986 were examined in order to study temporal changes of chromosomal aberrations over long periods (6-12 yr) following irradiation. From an analysis of the elapsed time between irradiation and cytogenetic examination, it was found that the frequency of dicentrics and rings did not decrease during the 6 yr period of observation

[en] Chromosomal analyses were performed in blood lymphocytes of 33 persons previously occupationally exposed to ionizing radiation. An increased frequency of chromosome aberrations, mainly dicentrics, a long time, up to 47 years after exposure, suggests that it is possible to use the method of unstable aberration analysis for assessment of previous radiation exposure. The enhanced yield of dicentrics was observed in persons who may have received irradiations above permitted limits. The aberrations represent a residue from a higher initially induced incidence. They can not be used reliably for retrospective dosimetry but do provide a marker for old exposure

[en] For thermal neutron imaging at the next generation of high-flux pulsed neutron sources a large area and fourfold segmented, hybrid, low-pressure, two-dimensional position sensitive, microstrip gas chamber detector, fabricated in a multilayer technology on glass substrates, is presently being developed, which utilizes a thin composite ¹⁵⁷Gd/CsI neutron converter. The present article focusses on the readout scheme and the data acquisition (DAQ) system. For position encoding, interpolating and fast multihit delay line based electronics is applied with up to eightfold sub-segmentation per geometrical detector segment. All signals, i.e. position, time-of-flight and pulse-height signals, are fed into deadtime-less 8-channel multihit TDC chips with 120 ps LSB via constant fraction and time-over-threshold discriminators, respectively. The multihit capability is utilized to raise the count rate limit in combination with a sum check algorithm for disentangling pulses from different events. The first version of the DAQ system uses the PCI form factor and comprises one slow control board and up to four boards for DAQ and real time histogramming with up to 2 MHz per board. Each DAQ board incorporates four TDC chips, up to 256 Mbytes of histogram memory and a 1 GFLOP DSP. The time of flight can be measured with a precision of a few LSB up to ranges >100 ms

[en] Spherical valves are supplied for high-head turbines. The drive of spherical valves designed and manufactured by Power Machines/LMZ provides opening by means of servomotors, and closing under the action of the moment created by counterweights. Selection of parameters for the spherical valve and its design are based on the assumption continuity of the water flow entering the turbine through the penstock. In case, when two or more hydro-units are installed at the HPP, the penstocks usually have pipe bifurcations (Fig.1). The design of the penstock should provide a uniform supply of water to all units without spin, rupture of continuity and pulsation. Given in the paper is an example of the HPP with two (2) hydro-units equipped with inlet spherical valves. In the course of operation valve rotor oscillations with different periods in time (T ≈ 15 sec.) were detected. When analyzing, no faults in the valve design and its mechanism of operation were detected. In the course of the tests, vibration parameters of the spherical valves were determined in the following operating conditions: each of the hydro-units running separately and both of them running simultaneously for different power output values. Based on the test results, operating conditions with maximum vibration of were located. The reasons of surging of perturbing forces acting on the rotor of the spherical valve were detected in the course of analysis of the penstock design. Possibility of accumulation of air at the penstock pipe bifurcations was found. When the air transported by the water achieved its critical value, this air appeared to be the cause of instability in the valve operation. The attention was drawn to necessity of taking into account this circumstance when designing penstock pipe bifurcations

[en] The paper discusses problems related to the closed fuel cycle. The paper briefly describes the solvent extraction process of spent FA regeneration with the quantitative extraction of U and Pu above 99 %, the process of U-Pu dioxide powder preparation as solid solutions and manufacture of fuel cores there of followed by their fast reactor irradiation. Preliminary data are given on post-irradiation examinations of fuels of the burn-up above 11 % h.a. (author)

[en] Hyperfine magnetic fields induced on the nuclei of nonmagnetic ions ¹³⁹La and ⁸⁹Y in LaTiO₃ and YTiO₃, respectively, have been microscopically calculated. The dependence of the hyperfine fields on the orbital and magnetic structures of the compounds under study has been analyzed. The comparative analysis of the calculated and known experimental data confirms the existence of the static orbital structure in lanthanum and yttrium titanates.

[en] Mathematical model for the flexible rotor which has static and dynamic unbalance and enabled slip rolling on the compliant stator is developed. Also, rotation inertia, gyroscopic effect, bearings characteristics, internal hysteresis, and external viscous friction are included. The matrix approaches are used. The proposed model allows investigating the dynamic effect of total unbalance and stator displacements as an elastic and solid body on basis of the ordinary differential equations. (paper)

[en] Tumour markers (TM) are base plasma proteins with a carbohydrate component, produced by various types of tumor cells. 84 male liquidators aged from 30 to 50 y.o. were examined in the clinic of All-Russian Center of Emergency and Radiation Medicine in September 1994-April 1995. External irradiation exposure amongst liquidators varied from 2 to 30 sGr. TM concentration in serum and plasma were determined by conventional ELISA methods (CEA. AFP, CA19-9. PSA, NSE). The first (control) group was composed of liquidators with no GI tract pathology. The second group consisted of 28 liquidators with irradiation - induced cytogenetical disturbances in peripheral blood lymphocytes. The third group consisted included 28 liquidators with chronic GI tract diseases. In control group, levels of CA 19-9, CEA and AFP amounted to 4.7± 0.4 U/ml, 2.4± 0.8mg/ml, 2.1± 0.2 IU/ml, correspondingly. The CA 19-9 level has been shown to increase statistically significantly in the second (14.5±1.5 U/ml) and in the third group (17.8± 1.2 U/ml). A simultaneous elevation of CA 19-9 and CEA was found in 7.1% of the liquidators of the third group, the CA 19-9 level changes ranging from 63 to 708 U/ml. The mean value of PSA in all three groups remained within the discrimination concentration limits and amounted to 2.5± 0.4 U/ml. Concentration of NSE was equal to 29.9± 7.2 mg/ml in all three groups. Based on the data on frequencies of the tumour marker elevation, a group of 6 was selected.This group required a detailed dynamic examination because of the problem of remote consequences of the effect of complex factors of the Chernobyl Atomic Station accident upon its victims. (author)