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[en] During the critical period for grain number definition, the amount of biomass produced per unit absorbed radiation is more sensitive to nitrogen (N) supply in oilseed rape than in wheat, and reaches a higher value at high N. This response was investigated by combining experimental and modelling work. Oilseed rape and wheat were grown at three levels of N supply, combined with two levels of plant density at high N supply. Canopy photosynthesis and daytime radiation use efficiency (RUEA) were calculated with a model based on observed N-dependent leaf photosynthesis and observed canopy vertical distribution of light and leaf N. In oilseed rape, RUEA was higher than in wheat and, in contrast to wheat, the sensitivity to canopy leaf N content increased from the start to the end of the critical period. These results were partly explained by the higher leaf photosynthesis in oilseed rape vs wheat. In addition, oilseed rape leaves were increasingly shaded by the inflorescence. Thus, RUEA increased because more leaves were operating at non-saturating light levels. In both species, the vertical distribution of leaf N was close to that optimising canopy photosynthesis. The results are discussed in relation to possibilities for improvement of N productivity in these crops. (author)
[en] Evolution of neutron inelastic magnetic scattering (NIMS) spectra for CeInCu2 in the temperature range 10–130 K as well as their transformation at T = 10 K caused by the variation of Kondo temperature (TK) due to a chemical substitution in Ce for Ce1−x(La,Y)xInCu2 (x=0, 0.2) has been studied. The temperature dependence of energy and intensity of the CF transitions in these compounds are not in accordance with conventional single-ion CF effects. A joint analysis of NIMS data for CeInCu2, CeAl3 and Ce0.5La0.5Ni allows to conclude that all these compounds have qualitatively similar changes of 4f excitation spectra.
[en] We have experimentally studied a small Josephson junction array in the presence of microwave irradiation. The array has comparable energy scales for single-charge effects and the Josephson effect, resulting in a discrete set of macroscopic eigenenergy levels. Excitation of the array by low-power microwaves is possible at frequencies where the photon energy matches the level spacing. The microwave frequency and amplitude dependence show that the excitation mechanism involves resonant quantum coherent dynamics of the array.
[en] The distribution of the induced 5d magnetic moments across the Ce layers in [CeLaCe/Fe]57 and [LaCeLa/Fe]57 multilayers has been investigated by resonant X-ray magnetic reflectivity. The quantitative analysis of the energy dependence of the asymmetry ratios measured on top of several multilayer Bragg peaks required the determination of the composition profile across the period of the multilayer. In order to separate out the structural parameters of the Ce and La layers, resonant X-ray reflectivity measurements were carried out at the La and Ce L-edges as well as at the Fe K-edge. The induced Ce 5d magnetic profile which is derived from the XRMS spectra is found to oscillate in both samples, with however, a different depth dependence probably related to the influence of the different interfaces.
[en] Bulk Shield experiment representing a mock-up of the ITER inboard blanket and vacuum vessel was completed in 1997 at the 14 MeV Frascati Neutron Generator (FNG) at ENEA Frascati. The objective of the experiment was to verify the calculational methods and nuclear data files used in the design and shielding calculations for fusion reactor. The benchmark experiment was analysed using the discrete ordinates transport code DORT, and the sensitivity and uncertainty analysis code package SUSD3D developed within the EFF project. Neutron cross-sections taken from FENDL-1 and FENDL-2 evaluations were used in the transport calculation. The results were compared with the measured reaction rates and with those calculated by the Monte Carlo code MCNP4A using FENDL-1. Good agreement between MCNP and DORT results was observed. No significant difference between FENDL-1 and FENDL-2 results was found, FENDL-2 performing slightly better. The transport calculations were combined with the sensitivity and uncertainty analysis whose application has proven to be very useful in order to obtain information on the importance of various nuclear data in the neutron transport, to explain the discrepancies between the calculation and the measurement, or at least to discard some possible reasons for the discrepancy. The sensitivity analysis coupled with the covariance matrices can guide future nuclear data research and development. (author)
[en] In order to estimate the accuracy of calculation methods such as empirical formulas and Monte Carlo codes for neutron and gamma ray fluxes through a labyrinth connected with a room having a Cu target irradiated by 68-MeV-proton, experimental analyses are carried out. As results of the analyses, the followings are obtained. (1) The MCNP calculation is applicable to estimation of neutron and gamma ray dose equivalent rates in the labyrinth, although cross sections in the process of neutron thermalization and gamma ray production cross section should be modified for more precise estimation. (2) The empirical formulas are useful for estimation of neutron dose equivalent rate. However, an additional safety factor of 2 should be required to apply to the estimation of total dose equivalent rates, because the contribution of gamma ray dose equivalent rate increases with the distance in the labyrinth and becomes comparable to that of neutron dose equivalent rate at the distance longer than 20 m. (author)
[en] The Japan Atomic Energy Research Institute (JAERI) Nuclear Data Center has started evaluation work in cooperation with Japanese Nuclear Data Committee (JNDC) to produce a JENDL Photonuclear Data File. The JENDL Photonuclear Data File is provided for applications such as electron accelerator shielding and radiation therapy, and given for gamma-ray induced reactions up to 140 MeV. The photon absorption cross section is evaluated with the giant dipole resonance model and the quasi-deuteron model, and the decaying processes are estimated with the statistical model with preequilibrium correction by using MCPHOTO and ALICE-F codes. The intercomparison has been made of JENDEL Photonuclear Data File with other evaluated photonuclear data files such as BOFOD, CNDC, EPNDL, and LANL as well as experimental data available for the important elements. (author)
[en] This report is a summary of the results of the study relating to the socio-economical impact of the electrification by photovoltaic solar system in the zones of the project AIJ/RPTES. The localities concerned with the study are the provinces of BALE and the MOUHOUN. The data analyzes relating to the electrification by solar system of the zones of the project AIJ/RPTES, revealed that solar electrical energy contributed to a significant degree to the socio-economic development, especially at the level of the structures having profited from the solar equipment. The principal conclusions drawn from these analyzes attested that: the solar system corresponds as well as possible for rural environment as well on the technological level as on the capacity plan of maintenance. The following reasons come to corroborate this fact: the weakness of the costs of management of the photovoltaic modules; the photovoltaic technic, in spite of a low incidental maximum power (1 kw/ m2), satisfied the priority needs for the rural populations (lighting, access to information and education, conservation of the vaccines in the CSPS, etc). - be photovoltaic installations cause: an average financial profit by CSPS of 180 487.5 FCFA/an, and a financial economy in the parents of the new-born babies estimated at 36,600 FCFA/an in each CSPS; an average financial economy by household of 49,452 FCFA/an
[fr]Le present rapport est une synthese des resultats de l'etude portant sur l'impact socio-economique de l'electrification par systeme solaire photovoltaique dans les zones d'intervention du projet AIJ/ RPTES. Les localites concernees par l'etude sont les provinces des BALE et du MOUHOUN. Les analyses des donnees portant sur l'electrification par systeme solaire des zones d'intervention du projet AIJ/RPTES, ont revele que l'energie electrique solaire a contribue de façon significative au developpement socio-economique surtout au niveau des structures ayant beneficie des equipements solaires. Les principales conclusions tirees de ces analyses attestent que : -Le modele d'electrification, a savoir le systeme solaire, correspond au mieux pour le milieu rural tant sur le plan technologique que sur le plan capacite d'entretien. Les raisons suivantes viennent corroborer ce fait : la faiblesse des couts de gestion des modules photovoltaiques -la technique photovoltaique, malgre une puissance maximale incidente faible (1 kW/m2), satisfait les besoins prioritaires des populations rurales (eclairage, acces a l'information et a l'education, conservation des vaccins dans les CSPS, etc.). - es installations photovoltaiques occasionnent : un gain financier moyen par CSPS de 180 487,5 FCFA/an, et une economie financiere chez les parents des nouveau-nes estimee a 36 600 FCFA/an dans chaque CSPS ; une economie financiere moyenne par menage de 49 452 FCFA/an
[en] Isotope shifts and hyperfine structure have been measured in the 4f7 5d6s2 9D6 - X9 D6 (;38 024. 9 cm-1) transition in atomic gadolinium using high-resolution resonance ionization mass spectroscopy. Excitation was performed as a resonance-enhanced two-photon transition with the 4f7 5d6s6p 9F7 state as an intermediate level. Selective population of hyperfine states in the first excitation step allowed assignment of all transitions in the complex hyperfine spectrum of the odd isotopes 155,157Gd and evaluation of the magnetic dipole and electric quadrupole hyperfine structure constants for the X 9D6 state. Measured values for the isotope shifts of all stable Gd isotopes have been used to derive specific mass shift and field shift factors. The obtained spectroscopic information leads to the conclusion that the X 9D6 state is a 4f75d6s8s configuration
[en] The effects of gamma irradiation (0.5 and 2.0 kGy), antimicrobial agents (5% sodium chloride and 1% potassium sorbate) and modified atmosphere (100% CO2) packaging (MAP) on histamine production by Morganella morganii were examined in mackerel fillets during 8 days of cold storage. MAP combined with antimicrobial agents was also applied to the fillets. The changes in histamine levels, M. morganii and total aerobic bacterial counts were determined during the storage. All methods used in this study showed beneficial effect in controlling bacterial growth and histamine production on mackerel fillets during 2-3 days of storage. MAP combined with 5% sodium chloride has more retarding effect on production of histamine than the other methods. For M. morganii, maximum inhibition effect was found at the dose of 2.0 kGy. Irradiation with a dose of 2.0 kGy, MAP combined with sodium chloride and MAP were also found to have the most inhibiting effects on total aerobic bacterial count during the storage