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The paper corrugation tube is an innovative kind of energy absorbing structure and shock absorber which can play an important role on the cushioning energy absorption for airdrop equipments and transportation packaging. The deformation characteristics and failure modes of the regular triangle, quadrangle, pentagon and hexagon paper corrugation tubes were comparatively studied by a series of axial static compression experiments, the cushioning energy absorption was evaluated by the seven characteristic parameters (e.g. initial peak force, mean crush force, total energy absorption, specific energy absorption, crush force efficiency, unit area energy absorption and stroke efficiency), and the influences of tube direction, cross-sectional shape, tube length and compression rate on failure modes and cushioning energy absorption were analyzed and compared. These researches showed that the tubes along X direction only have the accordion deformation mode, yet the tubes along Y direction have four deformation modes including steady state progressive buckling, Euler buckling, angular tear and transverse shear. For the paper corrugation tubes along Y direction, the cross-sectional shape has obvious influence on the cushioning energy absorption of structures, and the specific energy absorption and unit area energy absorption of regular triangle and pentagon tubes are better than those of the tubes with regular quadrilateral and hexagonal cross-section at compression rates of 12 and 48mm/min. The tube length of 150 mm or compression rate of 72 mm/min would cause the increase of contribution proportion of non-ideal deformation mode and the decrease of cushioning properties. The paper corrugation tubes along X direction have more stable and controllable deformation mode, yet the paper corrugation tubes along Y direction have better cushioning energy absorption.

An abrupt change will occur when the system is forced to across a critical threshold. This study presents a novel early warning indicator—the changing normalized dynamic range. We use a one‐variable climate model and three simple folding models to test the performance of the new early warning indicator. The results show that the present indicator exhibits a statistically significant increase or decrease in all of tests at a significance level of α =.05 before a dynamical system with a folding bifurcation approaches a tipping point. Comparing the well‐known autocorrelation coefficient with the normalized dynamic range, it is found that autocorrelation coefficient performs well in most of tests, which shows an almost monotonous increasing or decreasing trend for an upcoming abrupt change. However, autocorrelation coefficient exhibits a diametrically opposite trend for a noise‐induced abrupt change in a two‐dimensional vegetable model. The kurtosis coefficient can perform well in most of the tests used in this study, however, fails to give an early warning in a particular case. Moreover, the magnitude of change of the autocorrelation and kurtosis is much smaller than that of the normalized dynamic range before the four folding models approach its tipping point. Therefore, the performance of the new indicator for warning an abrupt change in advance is better than that of the autocorrelation coefficient as well as kurtosis coefficient, which can make up for the deficiency of the kurtosis coefficient and autocorrelation coefficient to some extent. [ABSTRACT FROM AUTHOR]

Elastic and inelastic scattering of α-particles from 32S has been theoretically studied at Elab = 386 MeV using three different potentials. For this, the phenomenological Woods–Saxon parameterized potential, single folding cluster potential, and the high-energy approximation model have been used. The results of our calculations have been compared with the experimental differential cross sections obtained from previously measured angular distributions. Our method of calculations successfully reproduces the experimental data. The values of the total reaction cross-section σR as well as the deformation parameters have been calculated and compared with those available in the literature. [ABSTRACT FROM AUTHOR]

The paper corrugation tube is an innovative kind of energy absorbing structure and shock absorber which can play an important role on the cushioning energy absorption for airdrop equipments and transportation packaging. The deformation characteristics and failure modes of the regular triangle, quadrangle, pentagon and hexagon paper corrugation tubes were comparatively studied by a series of axial static compression experiments, the cushioning energy absorption was evaluated by the seven characteristic parameters (e.g. initial peak force, mean crush force, total energy absorption, specific energy absorption, crush force efficiency, unit area energy absorption and stroke efficiency), and the influences of tube direction, cross-sectional shape, tube length and compression rate on failure modes and cushioning energy absorption were analyzed and compared. These researches showed that the tubes along X direction only have the accordion deformation mode, yet the tubes along Y direction have four deformation modes including steady state progressive buckling, Euler buckling, angular tear and transverse shear. For the paper corrugation tubes along Y direction, the cross-sectional shape has obvious influence on the cushioning energy absorption of structures, and the specific energy absorption and unit area energy absorption of regular triangle and pentagon tubes are better than those of the tubes with regular quadrilateral and hexagonal cross-section at compression rates of 12 and 48mm/min. The tube length of 150 mm or compression rate of 72 mm/min would cause the increase of contribution proportion of non-ideal deformation mode and the decrease of cushioning properties. The paper corrugation tubes along X direction have more stable and controllable deformation mode, yet the paper corrugation tubes along Y direction have better cushioning energy absorption. [ABSTRACT FROM AUTHOR]

In this work, we simultaneously reanalyzed the differential elastic scattering cross-sections (d σ / d Ω) and the vector analyzing power ( A y ) of p + 6 He elastic scattering. This analysis was performed using the folded optical model for both real central and spin-orbit (SO) potentials, respectively. For the imaginary central, we used the usual Woods-Saxon (WS) form. Three different model density distributions are used to calculate the potential. We aimed to examine the applicability of the microscopically derived SO potential and the structure effect of 6He nucleus. The presence of the A y experimental data of p + 6 He makes it interesting for this study. Our calculations showed that the three densities gave similar predictions for the cross-sections data. The three microscopic SO potentials calculations of A y are not in a good agreement with the experimental data. We concluded that the SO formalism in its current form needs more investigations for exotic halo nuclei. [ABSTRACT FROM AUTHOR]

The present study reports a systematic analysis of the cross section and analyzing power of the isobaric single charge-exchange (p , n) reactions at low energies (from 23 to 45 MeV) within the framework of the Lane model. For the latter, the G -matrix folding model with Argonne V18 nucleon-nucleon potential is used to treat the isospin dependence of not only the central but also the spin-orbit components of the in-medium nucleon-nucleon interaction. Results obtained show that the isospin-density dependence of the G -matrix with Argonne V18 interaction provides a good overall description of the cross section and analyzing power data of several isobaric single charge-exchange (p , n) reactions on different targets. This dependency should be, therefore, taken into account in future calculations with the G -matrix interaction. Our study also suggests that the neutron excess densities should be used, instead of the conventional isovector densities, to determine the transition densities in the charge-exchange (p , n) reactions on different targets, especially on those having a small number of neutron excess. [ABSTRACT FROM AUTHOR]

Angular distributions in the elastic scattering of 8B from 12C and 58Ni targets at different energies have been analyzed in the framework of the double-folding (DF) optical model. The real central part of the nuclear optical potential is obtained by folding the M3Y effective interaction with the cluster density distribution of the 8B nucleus. The experimental angular distributions have been successfully reproduced. This confirms the validity of the cluster structure of the 8B nucleus. [ABSTRACT FROM AUTHOR]

Detailed study of the behavior of experimental differential cross sections for the 16О + 12С-, 12С + 12С-elastic scatte¬ring in the energy range from 1 to 200 MeV/nucleon have been carried out. It is found that differential cross sections in the range of transfer momentum from 0 to 3-4 fm-1 shows the diffraction character for scattering in the overall energy range. The behavior features of the allocations of the first eight diffraction maxima and minima as well values of cross-sections in the maxima at the change of the interaction energy have been analyzed. It has been received energy-dependent optical potentials of the interaction for examines systems at the full range of energies. The obtained potentials describe the available experimental data satisfactorily and reproduce typical features of diffractive scattering cross sections.

The 16O + 12C scattering data originating from various measurements in the energy range from 1 to 100 MeV/nucleon have been analyzed within optical model (OM). As a result the global energy dependent 16O + 12C - OM-potential has been obtained. Satisfactory description of experimental data is achieved. While analyzing differential cross sections of the elastic scattering and fusion cross sections were calculated using var-ious types of optical potentials.