439 research outputs found
LOADS ACTING ON THE LOCOMOTIVE SYSTEM OF PROFESSIONAL FEMALEVOLLEYBALL PLAYERS DURING THE LANDING PHASE OF SPIKES AND BLOCKS
The purpose of this study was to identify force and time characteristics of ground reaction forces produced during the landing phase of volleyball technical elements: blocks and spikes. Applying piezoelectric dynamometry and video recording, a series of tests were carried out with the participation of four female volleyball players of the first team of AZS AWF sports club competing in the Female Volleyball League. The recorded force vs time line graphs of ground reaction Rx(t), Ry(t) and Rz(t) were used to calculate the values of kinematic-dynamic parameters that describe the level of dynamic loads. Results show that the majority of loads in these movement tasks is significant and may be traumatogenic
Study of Deformation Effects in the Charged Particle Emission from 46Ti
The 46Ti compound nucleus, as populated by the fusion-evaporation reaction
27Al + 19F at the bombarding energy of 144 MeV, has been investigated by
charged particle spectroscopy using the multidetector array ICARE at the
VIVITRON tandem facility of the IReS (Strasbourg). The light charged particles
have been measured in coincidence with evaporation residues. The CACARIZO code,
a Monte Carlo implementation of the statistical-model code CASCADE, has been
used to calculate the spectral shapes of evaporated alpha-particles which are
compared with the experimental spectra. This comparison indicates the possible
signature of large deformations of the compound nucleus.Comment: 6 pages, 4 figures, Proceedings od the Zakopane 20004 Symposium, to
be published in Acta Phys. Pol. B36 (2005
Evidence for the Jacobi shape transition in hot 46Ti
The gamma-rays from the decay of the GDR in 46Ti compound nucleus formed in
the 18O+28Si reaction at bombarding energy 105 MeV have been measured in an
experiment using a setup consisting of the combined EUROBALL IV, HECTOR and
EUCLIDES arrays. A comparison of the extracted GDR lineshape data with the
predictions of the thermal shape fluctuation model shows evidence for the
Jacobi shape transition in hot 46Ti. In addition to the previously found broad
structure in the GDR lineshape region at 18-27 MeV caused by large
deformations, the presence of a low energy component (around 10 MeV), due to
the Coriolis splitting in prolate well deformed shape, has been identified for
the first time.Comment: 8 pages, 4 figures, proceedings of the COMEX1 conference, June 2003,
Paris; to be published in Nucl. Phys.
GDR Feeding of the Highly-Deformed Band in 42Ca
The gamma-ray spectra from the decay of the GDR in the compound nucleus
reaction 18O+28Si at bombarding energy of 105 MeV have been measured in an
experiment using the EUROBALL IV and HECTOR arrays. The obtained experimental
GDR strength function is highly fragmented, with a low energy (10 MeV)
component, indicating a presence of a large deformation and Coriolis effects.
In addition, the preferential feeding of the highly-deformed band in 42Ca by
this GDR low energy component is observed.Comment: 6 pages, 2 figures, Proceedings of the Zakopane2004 Symposium, to be
published in Acta Phys. Pol. B36 (2005
Strong Deformation Effects in Hot Rotating 46Ti
Exotic-deformation effects in 46Ti nucleus were investigated by analysing the
high-energy gamma-ray and the alpha-particle energy spectra. One of the
experiments was performed using the charged-particle multi-detector array ICARE
together with a large volume (4"x4") BGO detector. The study focused on
simultaneous measurement of light charged particles and gamma-rays in
coincidence with the evaporation residues. The experimental data show a
signature of very large deformations of the compound nucleus in the Jacobi
transition region at the highest spins. These results are compared to data from
previous experiments performed with the HECTOR array coupled to the EUROBALL
array, where it was found that the GDR strength function is highly fragmented,
strongly indicating a presence of nuclei with very large deformation.Comment: 10 pages, 6 figures, Proceedings of the Zakopane Conference on
Nuclear Physics, to be published in Acta Phys. Pol. B (2007
Evaluation of the possibility of using the water of the Bystrytsya-Nadvirnyans'ka River in Cherniiv (Ukraine) to supply the population with drinking water
The article presents the results of the research carried out in order to assess the possibility of using surface water of the Bystrytsya-Nadvirnyans'ka River in Cherniiv (western Ukraine), for the public supply of water intended for human consumption. For this purpose an existing database that contains the results of analyses of surface water samples collected in 1999, 2002, 2005, 2008, 2011 and 2014 was used. Each year, from 8 to 13 samples were collected from the Bystrytsya-Nadvirnyans'ka River in Cherniiv. Physicochemical analyses of the samples taken included the determination of pH value, temperature, TDS, alkalinity, hardness, dissolved oxygen, BOD5, COD, suspended solids and ions: Ca2+, Mg2+, Na+, K+, Fe2+, NH4+, Cu2+, Cl-, SO42-, PO43-, HCO3-, NO2-, NO3-. These chemical analyses were verified by calculation of errors based on the ionic balance.
The results of the analyses were referred to the polish applicable requirements for surface water used for public supply of water intended for human consumption and to the regulation regarding the classification of the surface water status and environmental quality standards for priority substances. The results indicate that water of the Bystrytsya-Nadvirnyans'ka River in the area of Cherniiv was out of the class in the years 1999 and 2002 due to exceeding the limit values for category A3 for Cu2+. On the basis of incomplete assessment of the status of the Bystrytsya-Nadvirnyans'ka River water (due to the tests limitation to the physical and chemical components) determined that the water has a bad status because it exceeded the limits for class II for Cl-, SO42-, NO3- and TDS. In the samples collected in 1999 and 2002 it is also observed exceeding the maximum limit concentrations for Cu2+
Extraction of thermal and electromagnetic properties in 45Ti
The level density and gamma-ray strength function of 45Ti have been
determined by use of the Oslo method. The particle-gamma coincidences from the
46Ti(p,d gamma)45Ti pick-up reaction with 32 MeV protons are utilized to obtain
gamma-ray spectra as function of excitation energy. The extracted level density
and strength function are compared with models, which are found to describe
these quantities satisfactorily. The data do not reveal any single-particle
energy gaps of the underlying doubly magic 40Ca core, probably due to the
strong quadruple deformation
The damping width of giant dipole resonances of cold and hot nuclei: a macroscopic model
A phenomenological macroscopic model of the Giant Dipole Resonance (GDR)
damping width of cold- and hot-nuclei with ground-state spherical and
near-spherical shapes is developed. The model is based on a generalized Fermi
Liquid model which takes into account the nuclear surface dynamics. The
temperature dependence of the GDR damping width is accounted for in terms of
surface- and volume-components. Parameter-free expressions for the damping
width and the effective deformation are obtained. The model is validated with
GDR measurements of the following nuclides, K, Ca, Sc,
Cu, Sn,Eu, Hg, and Pb, and is
compared with the predictions of other models.Comment: 10 pages, 5 figure
Charged particle decay of hot and rotating Mo nuclei in fusion-evaporation reactions
A study of fusion-evaporation and (partly) fusion-fission channels for the
Mo compound nucleus, produced at different excitation energies in the
reaction Ti + Ca at 300, 450 and 600 MeV beam energies, is
presented. Fusion-evaporation and fusion-fission cross sections have been
extracted and compared with the existing systematics. Experimental data
concerning light charged particles have been compared with the prediction of
the statistical model in its implementation in the Gemini++ code, well suited
even for high spin systems, in order to tune the main model parameters in a
mass region not abundantly covered by exclusive experimental data.
Multiplicities for light charged particles emitted in fusion evaporation events
are also presented. Some discrepancies with respect to the prediction of the
statistical model have been found for forward emitted -particles; they
may be due both to pre-equilibrium emission and to reaction channels (such as
Deep Inelastic Collisions, QuasiFission/QuasiFusion) different from the
compound nucleus formation.Comment: 14 pages, 14 figure
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