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111.
112.
The current study investigated the ability of subjects to perceive source characteristics (the gender of a human walker) of a naturally occurring auditory event (human walking). A number of acoustic properties were measured and subjected to statistical analyses in order to identify those properties that differentiate male and female walking footsteps. A principal component analysis on the statistical properties of the spectral energy distributions then identified two classes of information that were important in determining subject perception of the gender of a walker: (1) the spectral peak which integrates the information about the spectral central tendency of frequency and shape of the spectral peak; and (2) the contribution of high-frequency spectral components. A follow-up experiment then manipulated these spectral properties to verify their contributions in the perceptual classification of walker gender. Additionally, the effect of shoe on the gender judgement in walking sequences was assessed by having both male and female walkers wear male's shoes. 相似文献
113.
C. Letty A. Pastore E. Mastorakos R. Balachandran S. Couris 《Experimental Thermal and Fluid Science》2010,34(3):338-345
Emission spectra from electrical and laser sparks in flowing methane–air mixtures of various compositions have been collected and analysed. The differences and similarities between the electrical and laser sparks in the context of their emission are discussed. The emission spectra from the laser spark were characterized by a weak continuum, onto which several strong atomic lines and some molecular bands were superimposed, in contrast to the spectra of electrical spark where a strong continuum, few atomic lines and several strong molecular bands were evident, making thus the laser spark spectroscopy a more accurate technique to measure hydrocarbon concentration. For both types of spark, the total intensity of the CN chemiluminescence around 388 nm was found to correlate almost linearly with fuel concentration in methane–air mixtures. 相似文献
114.
Syrine Daoudi Abderrahmane Semmeq Michael Badawi Xavier Assfeld Youssef Arfaoui Mariachiara Pastore 《Journal of computational chemistry》2019,40(29):2530-2538
Seven free base porphyrins employed in dye-sensitized photoelectrosynthetic cells are investigated with the aim of benchmarking the ability of different density functional theory (DFT) and time-dependent DFT approaches in reproducing their structure, vertical, and E0-0 excitation energies and the energy levels alignment (red-ox properties) at the interface with the TiO2. We find that both vertical and E0-0 excitation energies are accurately reproduced by range-separated functionals, among which the ω B97X-D delivers the lowest absolute deviations from experiments. When the dye/TiO2 interface is modeled, the physical interfacial energetics is only obtained when the B3LYP functional is employed; on the other hand, M06-2X (54% of exchange) and the two long-range corrected approaches tested (CAM-B3LYP and ω B97X-D) excessively destabilize the semiconductor conduction band levels with respect to the dye's lowest unoccupied molecular orbitals (LUMOs), predicting no pathway for electron injection. © 2019 Wiley Periodicals, Inc. 相似文献
115.
Anna Maria Pastore 《Geometriae Dedicata》1989,30(2):235-246
We study homogeneous Riemannian structures belonging to the class 13 of the classification given by Tricerri and Vanhecke. The main result is the following: a connected, simply connected Riemannian manifoldM admits a homogeneous structureT of type 13,T3, if and only ifM is isometric to a hyperbolic space
n
.This work was partially supported by M.P.I. 相似文献
116.
A new algorithm for solving integral equations of the theory of liquids at fixed pressure is introduced. Combining this technique with the Lee's star function approximation for the chemical potentials, we obtain an efficient method to investigate fluid-phase diagrams of binary mixtures. We have tested the capabilities of such technique to study symmetric and asymmetric phase diagrams in nonadditive hard spheres and Lennard-Jones mixtures. We find that the integral equation theories, although approximate, can provide a flexible tool to determine the fluid-phase diagrams whose accuracy is critically dependent on the quality of the closure and of the resulting chemical potentials. 相似文献
117.
V. A. Drebushchak G. Intini L. Liberti M. Notarnicola T. Pastore T. N. Drebushchak V. V. Boldyrev 《Journal of Thermal Analysis and Calorimetry》2007,90(1):143-146
Natural dredged sediments contaminated by PCBs from the heavy industrialized harbor of Taranto (S. Italy) on the Ionian Sea,
previously dechlorinated by mechanical activation in different ball mills (SPEX and AGO-2), together with synthetic mixtures
emulating the contaminated sediments, were submitted to thermogravimetric and calorimetric measurements as well as to X-ray
powder diffraction in order to clarify the dechlorination reaction mechanism.
Both major sediment components, i.e., carbonates and clay minerals, were found to be affected by the mechanical activation.
As trace pollutants like PCBs are concentrated in clays, the mechanical activation of sediments increases the release of pollutants
yielding a more active decontamination.
DSC results were less informative as calorimetric peaks from different thermal events were found to overlap. 相似文献
118.
de Aráujo Álvaro Alberto Pastore Gláucia M. Berger Ralf G. 《Applied biochemistry and biotechnology》2002,98(1-9):747-751
The production of 6-pentyl-α-pyrone (6-PP), an unsaturated d-lactone with a strong coconut-like aroma was studied and compared with liquid and solid substrates. A fungi strain that produces
coconut aroma compound was selected. The liquid medium of the submerged culture was used to impregnate a solid support of
sugarcane bagasse in SSF (Solid State Fermentation). This substrate was adequate for growth and aroma production; the concentration
obtained using SSF was higher than using liquid fermentation process. In the present work, it is demonstrated that, by solid-state-fermentation
process, it is possible to produce 6-PP. The amount of 6-PP produced using a solid state substrate, following a 5 d culture,
was 3 mg/g dry matter. Therefore, the amount of 6-PP produced during solid-state-fermentation process is higher than that
reported in literature for submerged process. 相似文献
119.
We study, using Monte Carlo simulations, the cavity and the bridge functions of various hard sphere fluids: one component system, equimolar additive, and nonadditive binary mixtures. In particular, we numerically check the assumption of local dependency of the bridge functions from the indirect correlation functions, on which most of the existing integral equation theories hinge. We find that this condition can be violated either in the region around the first and second neighbors shell, or inside the hard core, for the systems here considered. The violations manifest themselves clearly in the so-called Duh-Haymet plots of the bridge functions versus the indirect correlation functions and become amplified as the coupling of the system increases. 相似文献
120.
Celestino Angeli Mariachiara Pastore Renzo Cimiraglia 《Theoretical chemistry accounts》2007,117(5-6):743-754
The n-electron valence state perturbation theory (NEVPT) is a form of multireference perturbation theory which is based on a zero
order reference wavefunction of CAS-CI type (complete active space configuration interaction) and which is characterized by
the utilization of correction functions (zero order wavefunctions external to the CAS) of multireference nature, obtained
through the diagonalization of a suitable two-electron model Hamiltonian (Dyall’s Hamiltonian) in some well defined determinant
spaces. A review of the NEVPT approach is presented, starting from the original second order state-specific formulation, going
through the quasidegenerate multi-state extension and arriving at the recent implementations of the third order in the energy
and of the internally contracted configuration interaction. The chief properties of NEVPT—size consistence and absence of
intruder states—are analyzed. Finally, an application concerning the calculation of the vertical spectrum of the biologically
important free base porphin molecule, is presented. 相似文献