Hyper-Kamiokande is a next generation water Clierenkov detector, an order of magnitude larger than Super-Kamiokande. capable of large and diverse physics studies. Among these, it will study long ...baseline oscillation physics with great detail, thanks not only to a larger volume and higher detection efficiency, but also to an improved accelerator and near detector system at J-PARC. We study the effect of a new systematic error model 011 the overall sensitivity of the experiment to the neutrino oscillation parameters, with particular care for the CP violating phase. A variety of theoretical models will benefit from a precise measurement of δCP, which Hyper-Kamiokande has the capability of constraining, with good precision. The accuracy of the measurement, however, is dictated by the systematic uncertainties and hence it is essential to assess the impact of the new error model 011 the sensitivity.
The Accelerator Neutrino Neutron Interaction Experiment (ANNIE) aims to make a unique measurement of neutron yield from neutrino-nucleus interactions and to perform R&D for the next generation of ...water-based neutrino detectors. In this paper, we characterize beam-induced neutron backgrounds in the experimental hall at Fermi National Accelerator Laboratory. It is shown that the background levels are sufficiently low to allow the next stage of the experiment to proceed. These measurements are relevant to other Booster Neutrino Beam (BNB) 1 experiments located adjacent to ANNIE Hall, where dirt neutrons and sky-shine could present similar backgrounds.
The aim of this work is to investigate the structural properties of the (Pb1-xErx)TiO3 (PET) powders, with x varying from 0.01 to 0.08, prepared by the polymeric precursor method. Combined X-ray ...diffraction, Raman spectroscopy and ab initio calculation reveal a diffuse phase-transition of a tetragonal to a cubic phase. The crystalline models built allowed to calculate electronic properties and to analyze the behavior of the doping element in the structure of the material, which are consistent with the experimental results that indicate the beginning of phase-transition from tetragonal to cubic.
We discuss the nature of visible photoluminescence (PL) at room temperature in amorphous calcium titanate in the light of the results of recent experimental and quantum mechanical theoretical ...studies. Our investigation of the electronic structure involved the use of first-principle molecular calculations to simulate the variation of the electronic structure in the calcium titanate crystalline phase, which is known to have a direct band gap, and we also made an in-depth examination of amorphous calcium titanate. The results of our theoretical calculations of amorphous calcium titanate indicate that the formation of fivefold coordination in the amorphous system may introduce delocalized electronic levels in the highest occupied and the lowest unoccupied molecular orbitals. These delocalized electronic levels are related to the formation of a tail in the absorbance spectrum curve. The results indicate that amorphous calcium titanate has the conduction band near the band gap dominated by Ca states contribution. Experimental optical absorption measurements showed the presence of a tail. These results are interpreted by the nature of these exponential optical edges and tails, associated with defects promoted by the disordered structure of the amorphous material. We associate them with delocalized states in the band gap.
An electronic nose for food analysis Di Natale, C; Macagnano, A; Davide, F ...
Sensors and actuators. B, Chemical,
10/1997, Letnik:
44, Številka:
1
Journal Article, Conference Proceeding
Recenzirano
Since the first developments of electronic noses, food analysis has been considered as one of its most useful applications. In this paper an electronic nose based on quartz microbalances coated with ...metallo-porphyrins and related compounds is presented and illustrated. Extensive tests on various substances playing key roles in food analysis show that sensing properties of the sensing materials (in terms of sensitivity and selectivity) can be exploited for electronic nose applications devoted to the analysis of various kinds of foods. The versatility of this system has been successfully tested on different kinds of foods, such as fish, meat, vegetable and wine for which results are shown.
This communication describes, for the first time, the growth of SnO2 nanoribbons by a controlled carbothermal reduction process. An analysis of the transmission electron microscopy image revealed ...that these nanoribbons have a well-defined shape, with a typical width in the range of 70-300 nm. In general, the nanostructured ribbons were more than 100 microns in length. The results reported here support the hypothesis that this ribbon-like nanostructured material grows by a vapor-solid process. This study introduces two hypotheses to explain the SnO2 nanoribbon growth process.
The results of both optimization and tests to prove the suitability of an array of quartz microbalance sensors (QMBs) modified with various metalloporphyrins for the determination of food freshness ...are presented and discussed. As far as optimization is concerned, it was found that a minimum amount of 50 μg of metalloporphyrin must be used for the modification of the quartz microbalance sensors in order to obtain the maximum sensitivity. The sensory behavior of five different porphyrins was subsequently studied. QMBs were modified using four different
meso-tetraphenylporphyrins: phenyl,
p-nitrophenyl,
p-bromophenyl,
p-methoxyphenyl and an octa-alkylporphyrin (
etio-porphyrin I), all loaded with a Co
2+ metal ion. A clear decrease in the sensitivity for the
etio-porphyrin I was observed whereas for the
meso-tetraphenyl-porphyrins the best response was obtained for the
p-nitrophenyl derivative. These results can be attributed to the different electron densities which are present at the metal center of the macrocycle. The determination of the response behavior with respect to methanol, thiophene, diethylamine and triethylamine of a sensor array consisting of rhodium, ruthenium, cobalt, and manganese
meso-tetraphenylporphyrin revealed that there is a clear difference in terms of the sensitivity and hence, the selectivity for the various QMBs. The rhodium and the cobalt-based QMBs were alike and demonstrated a preference for the gases with soft donating sites, i.e. thiophene and the amines. The QMBs based on ruthenium and manganese demonstrated distinctly different behavior. The ruthenium-based QMB demonstrated no clear preference for gases with either hard or soft donating sites, whereas the manganese-based QMB preferred gases with hard donating sites, i.e. methanol. These results led to the overall conclusion that this sensor array could be used for the analysis of complex gas mixtures, where the most prevalent gases fall under the categories of the amines, the alcohols and the sulphides.
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