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1.
The deep-inelastic deuteron structure function (SF) F2D in the covariant approach in the light-cone variables is considered. The neutron SF F2n is extracted from the deuteron and proton experimental data taking into account the relativistic deuteron model and the parametrization of F2n is obtained. The effect of the relativistic Fermi motion is estimated to be 6% at x0.7. The extracted neutron SF is used to verify the Gottfried sum rule. It is shown that the violation of the flavour symmetry of the sea can be large with increasing Q2. 相似文献
2.
Ihor R. Muts Falko M. Schappacher Vasyl’ I. Zaremba 《Journal of solid state chemistry》2007,180(8):2202-2208
New indides SrAu3In3 and EuAu3In3 were synthesized by induction melting of the elements in sealed tantalum tubes. Both indides were characterized by X-ray diffraction on powders and single crystals. They crystallize with a new orthorhombic structure type: Pmmn, Z=2, a=455.26(9), b=775.9(2), c=904.9(2) pm, wR2=0.0425, 485 F2 values for SrAu3In3 and a=454.2(2), b=768.1(6), c=907.3(6) pm, wR2=0.0495, 551 F2 values for EuAu3In3 with 26 variables for each refinement. The gold and indium atoms build up three-dimensional [Au3In3] polyanionic networks, which leave distorted hexagonal channels for the strontium and europium atoms. Within the networks one observes Au2 atoms without Au-Au contacts and gold zig-zag chains (279 pm Au1-Au1 in EuAu3In3). The Au-In and In-In distances in EuAu3In3 range from 270 to 290 and from 305 to 355 pm. The europium atoms within the distorted hexagonal channels have coordination number 14 (8 Au+6 In). EuAu3In3 shows Curie-Weiss behavior above 50 K with an experimental magnetic moment of 8.1(1) μB/Eu atom. 151Eu Mössbauer spectra show a single signal at δ=−11.31(1) mm/s, compatible with divalent europium. No magnetic ordering was detected down to 3 K. 相似文献
3.
O. P. Alemskaya V. M. Lelevkin A. V. Tokarev V. A. Yudanov 《High Energy Chemistry》2005,39(4):263-267
The synthesis of ozone from oxygen in a cylindrical ozonizer operating under surface discharge conditions with a plasma electrode was studied. The conditions of ozone synthesis were optimized. The dependence of ozone concentration and specific energy consumption on gas pressure in the plasma electrode and on distance between the coils of a corona electrode was determined. The results were compared with data obtained with the use of classical surface barrier discharge.__________Translated from Khimiya Vysokikh Energii, Vol. 39, No. 4, 2005, pp. 307–311.Original Russian Text Copyright © 2005 by Alemskaya, Lelevkin, Tokarev, Yudanov. 相似文献
4.
Yu. I. Aristov G. Di Marco M. M. Tokarev V. N. Parmon 《Reaction Kinetics and Catalysis Letters》1997,61(1):147-154
In this communication we present a low-temperature “solidification-melting” phase diagram for CaCl2/H2O solutions confined in KSK and KSM silica gels. At salt concentrations of 0–48 wt. %, the diagram has been found to lie below
the diagram reported for the bulk system by 15–30°C. It shows a depression of the solution melting point due to its confinment
to the pores. Several other peculiarities of melting and solidification in this system are also reported and discussed. Beside
fundamental interest, the data obtained could be of importance in many commercial areas such as refrigeration, accumulation
of low temperature heat, frost prevention in building materials,etc. 相似文献
5.
The multiplicity dependence of inclusive spectra of identified hadrons (π, K,
, K
S
0
, and Λ) produced in high-energy
p and pp collisions is studied. Analysis of experimental data on high-p
T hadron cross sections obtained at the Tevatron and RHIC is performed in the framework of z scaling. Independence of the scaling function ψ(z) on the multiplicity density dN
ch/dη is established. The multiplicity density measured in nucleon-nucleon collisions reaches much higher values than the corresponding
quantity [1/(0.5N
p)]dN
ch/dη obtained in heavy-ion collisions. Its influence on particle production reveals properties of self-similarity and fractality.
The relation between the scaling variable z and thermodynamic quantities (“heat capacity” and “temperature”) of the medium associated with the produced inclusive particle
is discussed. Search for z-scaling violation in
p and pp collisions at very high multiplicities as an indication of new-physics phenomena is suggested.
The text was submitted by the authors in English. 相似文献
6.
The influence of the cone algorithm parameters (E cut, E seed, R) on efficiency and characteristics of reconstructed jets in p-p collisions at the energy $\sqrt s $ = 200 GeV is studied. Event generation was carried out using the Monte Carlo code PYTHIA. The fraction of dijet event production as a function of transverse momentum of the hard process $\hat p_ \bot $ for different algorithm parameters is studied. The dependence of energy and parton direction reconstruction accuracy for dijet events and two leading jets in N-jet (N Jet ≥ 2) events on the algorithm parameters is found. The results of jet modeling are compared with predictions obtained in the framework of z-scaling and experimental data obtained at RHIC. It is proved that the slope parameter of the scaling function is independent of the algorithm parameters in the transverse jet energy range E T Jet = 25–60 GeV. It is shown that in the region E T Jet < 25 GeV, strong dependence of invariant cross sections and the slope of the scaling function on the algorithm parameters is observed, and this dependence is enhanced with decreasing E T Jet . 相似文献
7.
Juan A. Colón Santana V. Singh V. Palshin E. M. Handberg A. G. Petukhov Y. B. Losovyj A. Sokolov Ihor Ketsman 《Applied Physics A: Materials Science & Processing》2010,98(4):811-819
We have characterized the local structure around the Cr atom, as a function of Cr content, in films of chromium-doped hydrogenated
amorphous diamond-like carbon (Cr-DLC) synthesized by plasma-enhanced chemical vapor deposition (PECVD). The composition appears
to be related to the structure and forward bias magnetoresistance in heterojunction devices. Chromium in diamond-like carbon
(DLC) has a chemical state much like chromium carbide and, at low Cr content, the Cr is dissolved in an amorphous DLC matrix
forming an atomic-scale composite. At higher Cr content, Cr is present as nano-composite and chromium carbide precipitates
preferentially form at the surface of the film. In these films of higher chromium concentration, a large coefficient of negative
magnetoresistance is observed in heterojunction devices with n-type silicon. 相似文献
8.
A. N. Georgobiania V. P. Tokarev A. M. Evloeva E. V. Perlov 《Bulletin of the Lebedev Physics Institute》2009,36(11):317-320
The results of the study of the Raman spectrum of TlGaSe2 single crystals are presented. The ability of these layered crystals to cleave into plates with mirror faces, being a consequence
of significant asymmetry of the chemical bond, makes them promising materials for photoelectric converters. 相似文献
9.
10.
The general features of particle production in hadron-hadron and hadron-nucleus collisions at high energy and transverse momentum using the concept of z-scaling are reviewed. z-Presentation of experimental data on the inclusive cross sections obtained at ISR, SPS, and Tevatron is presented and its properties are discussed. It is argued that the properties reflect the fundamental symmetries such as self-similarity, locality, and fractality. z-Scaling is used to predict particle yields in hadron-hadron and hadron-nucleus collisions at RHIC and LHC energies. The violation of z-scaling is considered as a signature of new physics phenomena. 相似文献