Probability Modeling Taking into Account Nonlinear Processes of a Deformation and Fracture for the Equipment of Nuclear Power Plants

At the solution of integrated tasks of strength, safe life and service safety maintenance for the nuclear power plants (NPP) equipment with slow reactors—water-moderated power reactors (WMPR) of VVER type and channel-type graphite-moderated power reactors (GMPR) of RBMK type arise necessity of physical and mathematical modeling of nonlinear processes of a deformation, fracture and damage at nonlinear probability statement. First of all, it concerns deriving determined, statistical and probabilistic characteristics of mechanical properties of reactor materials. Expectations and variation factors of mechanical properties’ characteristics obtained from experimental researches are inducted into the equations for the verification calculations at determination of static and cyclic strength margins with the use of nominal and local stresses and strains. For the improved determined and probability analysis of these margins modeling experimental researches of stress-strain states of the analyzed equipment are conducted. Special attention at such tests is given to concentration factors and variation factors of loading conditions. The final stage of estimation of basic normative and verification calculation accuracy at laboratory, modeling and test bench researches are full-scale pre-operational tests (cold-hot running-in) of pilot nuclear reactors with the use of the experimental mechanics methods. The conditions of safety service of the NPP equipment are estimated taking into account factors of reaching limiting states by criteria of risk of initiation of emergency situations

Theoretical and Experimental Analysis of Structural Properties of Load-Bearing Components of Thermonuclear Tokamak Installations

The chapter presents the results of research carried out in Mechanical Engineering Research Institute of the Russian Academy of Sciences that were focused on validation and application of design diagrams, methods and systems for measuring stresses under the modes of Tokamak instillation cooling and management of electromagnetic fields during startups. The examples of tensometric systems and results of measurements of stresses under cryogenic temperatures and strong magnetic fields as well as results of analysis of the states of stresses and strains of structurally heterogeneous components of load-bearing and conductive structures are presented. Operation conditions and limit states of Tokamak components are considered. Results of research summarized in the chapter demonstrate the correctness of the adopted design solutions, which result in a relatively low level of local stresses in the load-bearing components of the thermonuclear installations

PHARMACOKINETIC RESEARCH OF POTENTIAL HYGOGLICEMIC DRUGS С7070

Introduction: The development of effective drugs for the treatment of diabetes is one of the urgent problems of modern medicine; we conducted pharmacokinetic studies of the innovative hypoglycemic drug - C7070, in rabbits and rats. Materials and Methods: The object of the study was substance C7070. Two methods of administration have been studied: intravenously and intragastrically. The concentration of C7070 is determined in blood plasma by a sensitive and selective HPLC method with tandem mass spectrometry detection. The range of detection was from 0.02 μg to 3876.00 μg in 1 ml of plasma in the animals under study. Chromatographic separation was performed on a 150 × 3.0 mm column of Zorbax Eclipce XDB C18 with a particle size of 3.0 μm (Agilent technologies, USA). To obtain stable results, a Zorbax Eclipce XDB C18 (Agilent technologies, USA) protection column of 12.5 × 3.0 mm with a particle size of 5.0 μm was used at 40 ° C for all analytical cycles. Ballast proteins in the test solutions were precipitated with acetonitrile followed by extraction of the analyte with ultrasound. Results and its Discussion: With intragastric administration, the maximum concentration (Cmax) of C7070 in blood plasma reached, on average, in rabbits through (tmax) 60 ± 0.1 minutes, in rats after 170.0 ± 79.8 minutes and was 34.6 ± 7.3 μg/ml and 17.6 ± 1.4 μg/ml, respectively. The half-life (t1/2) was prolonged and was 291.8 ± 17.1 minutes for rabbits and 225.2 ± 12.4 minutes for rats. The absolute bioavailability (fa) of C7070 in rabbits was 78.2 ± 1.0%, in rats 18.1 ± 2.0%. When administered intravenously, Cmax C7070 in blood plasma averaged 123.1 ± 23.7 μg/ml in rabbits and 337.6 ± 40.5 μg/ml in rats. The half-life period (t1/2) was prolonged and amounted to 225.5 ± 15.9 minutes for rabbits and 154.1 ± 5.1 minutes for rats. The Conclusion: The pharmacokinetic characteristics of a potential hypoglycemic drug C7070 in animals (rats, rabbits) under two routes of administration, intra-gastrointestinal and intravenous, were studied. The parameters obtained can be useful for clinical application and further studies of C7070 drugs based on it. Key words: C7070, diabetes mellitus, hypoglycemic agents, blood plasma of rabbits and rats, high-performance liquid chromatography, pharmacokinetics

π

We report on measurements of neutral pion production in the inclusive reactions d + C → π0 + x and d + Cu → π0 + x at an incident momentum of 4.5 GeV/c per nucleon. The experiments were performed on the LHE 90-channel lead glass γ-spectrometer. The cross sections were measured over the kinematical region specified by the inequalities θπ ≤ 16° and Eπ ≥ 2 GeV (in the laboratory frame). The cumulative number and transverse momentum dependencies of the exponent n in the invariant cross section parameterization Ed3 σ / d3 p ~ Atn are investigated by comparing of the observed cross sections for π0 production on carbon and copper targets in the intervals 0.6 ≤ X ≤ 1.8 and 0.04 ≤ pT2 ≤ 0.40 (GeV/c)2. The double differential cross section for the reaction d + C → π0 + x is measured using statistics of about 4.5 · 104π0 mesons. On the basis of these data we verified the so-called cluster mechanism of π0 production. We have compared our data for the reaction d + C → π0 + x, extrapolated to θπ = 0°, with the data from another experiments on π− production: d + C → π−(0°) + x (P = 1.75 and 2.88 GeV/c per nucleon) [1]; p + d → π−(180°) + x and p + d → π+(180°) + x (P = 8.9 GeV/c per nucleon) [2]; d + p → π−(0°) + x (P = 8.9 GeV/c per nucleon) [3]. The invariant cross sections were approximated by an exponential function Ed3 σ / d3 p ~ exp(−X / X0). The slope parameter X0 at different kinetic energies of the projectiles in the range of 1.05÷8.0 GeV per nucleon is determined

Tracker Operation and Performance at the Magnet Test and Cosmic Challenge

During summer 2006 a fraction of the CMS silicon strip tracker was operated in a comprehensive slice test called the Magnet Test and Cosmic Challenge (MTCC). At the MTCC, cosmic rays detected in the muon chambers were used to trigger the readout of all CMS sub-detectors in the general data acquisition system and in the presence of the 4 T magnetic field produced by the CMS superconducting solenoid. This document describes the operation of the Tracker hardware and software prior, during and after data taking. The performance of the detector as resulting from the MTCC data analysis is also presented

production in

We report on measurements of neutral pion production in the inclusive reactions d + C → π0 + x and d + Cu → π0 + x at an incident momentum of 4.5 GeV/c per nucleon. The experiments were performed on the LHE 90-channel lead glass γ-spectrometer. The cross sections were measured over the kinematical region specified by the inequalities θπ ≤ 16° and Eπ ≥ 2 GeV (in the laboratory frame). The cumulative number and transverse momentum dependencies of the exponent n in the invariant cross section parameterization Ed3 σ / d3 p ~ Atn are investigated by comparing of the observed cross sections for π0 production on carbon and copper targets in the intervals 0.6 ≤ X ≤ 1.8 and 0.04 ≤ pT2 ≤ 0.40 (GeV/c)2. The double differential cross section for the reaction d + C → π0 + x is measured using statistics of about 4.5 · 104π0 mesons. On the basis of these data we verified the so-called cluster mechanism of π0 production. We have compared our data for the reaction d + C → π0 + x, extrapolated to θπ = 0°, with the data from another experiments on π− production: d + C → π−(0°) + x (P = 1.75 and 2.88 GeV/c per nucleon) [1]; p + d → π−(180°) + x and p + d → π+(180°) + x (P = 8.9 GeV/c per nucleon) [2]; d + p → π−(0°) + x (P = 8.9 GeV/c per nucleon) [3]. The invariant cross sections were approximated by an exponential function Ed3 σ / d3 p ~ exp(−X / X0). The slope parameter X0 at different kinetic energies of the projectiles in the range of 1.05÷8.0 GeV per nucleon is determined

Check of the structure in photon pairs spectra at the invariant mass of about 38 MeV/c2

Results of analysis of the effective mass spectra of photon pairs produced in dC, dCu and pC interactions at momenta of 2.75, 3.83 and 5.5 GeV/c per nucleon, respectively, are presented. A structure at effective mass of about 38 MeV/c2 is observed. The results of testing the observed signal are presented. The test results support the conclusion that the observed signal is the consequence of detection of a particle with a mass of about 38 MeV/c2 decaying into a pair of photons

Check of the structure in photon pairs spectra at the invariant mass of about 38 MeV/

Results of analysis of the effective mass spectra of photon pairs produced in dC, dCu and pC interactions at momenta of 2.75, 3.83 and 5.5 GeV/c per nucleon, respectively, are presented. A structure at effective mass of about 38 MeV/c2 is observed. The results of testing the observed signal are presented. The test results support the conclusion that the observed signal is the consequence of detection of a particle with a mass of about 38 MeV/c2 decaying into a pair of photons

Photon and π0 pairs production in proton-nucleus and deuteron-nucleus interactions. Results of experiments on internal beams of the Nuclotron

The results of experiments on photon and π0 pairs production in interactions of 5.5 GeV/c protons, 2.75 and 3.83 GeV/c per nucleon deuterons with carbon and copper nuclei are presented. As previously reported (see. [1] and references therein), along with π0 and η mesons, a resonance structure in the invariant mass spectrum of two photons at Mγγ = 360 ± 7 ± 9 MeV is observed in the reaction dC → γ + γ + X at momentum 2.75 GeV/c per nucleon. Here are some results of testing the signal and results of statistical analysis of the experimental data which allow to explain the lack of appearance of the signal in other experiments [2, 3] and make predictions for possible appearances of the signal in upcoming experiments