321 research outputs found

    Surface impedance of copper MOB depending on the annealing temperature and deformation degree

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    Results of researches of influence of annealing temperature and deformation degree on mechanical features of copper MOB are presented. It is shown that minimal surface resistance is observed in copper samples that were subject to pre-deformation and were annealed in the range of temperatures 873…923K.Представлены результаты исследований влияния температуры отжига и степени деформации на электромеханические характеристики меди марки МОБ. Показано, что минимальное поверхностное сопротивление наблюдается у меди, деформированной и отожженной в интервале температур 873…923К.Представлені результати досліджень впливу температури відпалу та степені деформації на електромеханічні характеристики міді марки МОБ. Показано, що мінімальний поверхневий опір спостерігається у зразків міді, підверненої деформації і відпаленої в інтервалі температур 873…923К

    High-temperature oxidation of nuclear graphite with account of movement of the surface layer of oxidator

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    At high-temperature oxidation of nuclear graphite, the oxidant flow in the near-surface region is taken into account. Macro- and microscopic modeling of the oxidation of the near-surface layer was carried out. The calculation of the diffusion coefficient of gaseous components as a function of temperature and concentration is given. The influence of the motion of the surface layer of the oxidizer on the concentration of gaseous components is studied.При високотемпературному окисленні ядерного графіту врахований потік окислювача в приповерхневій області. Проведено макро- і мікроскопічне моделювання окислення приповерхневого шару. Наведено розрахунок коефіцієнта дифузії газоподібних компонент у залежності від температури і концентрації. Досліджено вплив обліку руху приповерхневого шару окислювача на концентрацію газоподібних компонентів.При высокотемпературном окислении ядерного графита учтен поток окислителя в приповерхностной области. Проведено макро- и микроскопическое моделирование окисления приповерхностного слоя. Приведен расчет коэффициента диффузии газообразных компонент в зависимости от температуры и концентрации. Исследовано влияние учета движения приповерхностного слоя окислителя на концентрацию газообразных компонентов

    Gamma-activation method for the element analysis of agricultural products after vacuum drying

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    Development of the combined technologies of drying allows one to speed up the process of moisture moving away from the dried material and to decrease the energy consumption per the production unit. The composition of macro- and microelements before and after drying of the dispersed materials was monitored by the nuclear-physical method. Quantometer method was used for definition of the intensity of oxidative processes at the level of cell membranes. And the method of electron microscopy was used for detection of possible destructive processes in organelles.Розробка комбінованих технологій сушіння дозволяє прискорювати процес відходу вологи з матеріалу і зменшувати витрати енергії на одиницю продукції. Склад макро- і мікроелементів до і після сушіння матеріалів був вивчений ядерно-фізичними методами. Метод реєстрації індукованого випромінювання використовувався для визначення інтенсивності окисних процесів на рівні мембран клітини. Метод електронної мікроскопії використовувався для виявлення можливих деструктивних процесів у клітині.Разработка комбинированных технологий сушки позволяет ускорять процесс ухода влаги из материала и уменьшать затраты энергии на единицу продукции. Состав макро- и микроэлементов до и после сушки материалов был изучен ядерно-физическими методами. Метод регистрации индуцированного излучения использовался для определения интенсивности окислительных процессов на уровне мембран клетки. Метод электронной микроскопии использовался для обнаружения возможных деструктивных процессов в клетке

    Gluon polarization in the nucleon from quasi-real photoproduction of high-pT hadron pairs

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    We present a determination of the gluon polarization Delta G/G in the nucleon, based on the helicity asymmetry of quasi-real photoproduction events, Q^2<1(GeV/c)^2, with a pair of large transverse-momentum hadrons in the final state. The data were obtained by the COMPASS experiment at CERN using a 160 GeV polarized muon beam scattered on a polarized 6-LiD target. The helicity asymmetry for the selected events is = 0.002 +- 0.019(stat.) +- 0.003(syst.). From this value, we obtain in a leading-order QCD analysis Delta G/G=0.024 +- 0.089(stat.) +- 0.057(syst.) at x_g = 0.095 and mu^2 =~ 3 (GeV}/c)^2.Comment: 10 pages, 3 figure

    The Deuteron Spin-dependent Structure Function g1d and its First Moment

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    We present a measurement of the deuteron spin-dependent structure function g1d based on the data collected by the COMPASS experiment at CERN during the years 2002-2004. The data provide an accurate evaluation for Gamma_1^d, the first moment of g1d(x), and for the matrix element of the singlet axial current, a0. The results of QCD fits in the next to leading order (NLO) on all g1 deep inelastic scattering data are also presented. They provide two solutions with the gluon spin distribution function Delta G positive or negative, which describe the data equally well. In both cases, at Q^2 = 3 (GeV/c)^2 the first moment of Delta G is found to be of the order of 0.2 - 0.3 in absolute value.Comment: fits redone using MRST2004 instead of MRSV1998 for G(x), correlation matrix adde

    Spin asymmetry A_1^d and the spin-dependent structure function g_1^d of the deuteron at low values of x and Q^2

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    We present a precise measurement of the deuteron longitudinal spin asymmetry A_1^d and of the deuteron spin-dependent structure function g_1^d at Q^2 < 1 GeV^2 and 4*10^-5 < x < 2.5*10^-2 based on the data collected by the COMPASS experiment at CERN during the years 2002 and 2003. The statistical precision is tenfold better than that of the previous measurement in this region. The measured A_1^d and g_1^d are found to be consistent with zero in the whole range of x.Comment: 17 pages, 10 figure

    A new measurement of the Collins and Sivers asymmetries on a transversely polarised deuteron target

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    New high precision measurements of the Collins and Sivers asymmetries of charged hadrons produced in deep-inelastic scattering of muons on a transversely polarised 6LiD target are presented. The data were taken in 2003 and 2004 with the COMPASS spectrometer using the muon beam of the CERN SPS at 160 GeV/c. Both the Collins and Sivers asymmetries turn out to be compatible with zero, within the present statistical errors, which are more than a factor of 2 smaller than those of the published COMPASS results from the 2002 data. The final results from the 2002, 2003 and 2004 runs are compared with naive expectations and with existing model calculations.Comment: 40 pages, 28 figure

    Measurement of the Spin Structure of the Deuteron in the DIS Region

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    We present a new measurement of the longitudinal spin asymmetry A_1^d and the spin-dependent structure function g_1^d of the deuteron in the range 1 GeV^2 < Q^2 < 100 GeV^2 and 0.004< x <0.7. The data were obtained by the COMPASS experiment at CERN using a 160 GeV polarised muon beam and a large polarised 6-LiD target. The results are in agreement with those from previous experiments and improve considerably the statistical accuracy in the region 0.004 < x < 0.03.Comment: 10 pages, 6 figures, subm. to PLB, revised: author list, Fig. 4, details adde

    The COMPASS Experiment at CERN

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    The COMPASS experiment makes use of the CERN SPS high-intensitymuon and hadron beams for the investigation of the nucleon spin structure and the spectroscopy of hadrons. One or more outgoing particles are detected in coincidence with the incoming muon or hadron. A large polarized target inside a superconducting solenoid is used for the measurements with the muon beam. Outgoing particles are detected by a two-stage, large angle and large momentum range spectrometer. The setup is built using several types of tracking detectors, according to the expected incident rate, required space resolution and the solid angle to be covered. Particle identification is achieved using a RICH counter and both hadron and electromagnetic calorimeters. The setup has been successfully operated from 2002 onwards using a muon beam. Data with a hadron beam were also collected in 2004. This article describes the main features and performances of the spectrometer in 2004; a short summary of the 2006 upgrade is also given.Comment: 84 papes, 74 figure
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