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In this work, copper and zinc nanoparticles were prepared using a pulsed laser ablation method, using a Nd- YAG laser with a wavelength of 532 nm, a fixed ablation energy of 600 mJ, and a number of different pulses (300, 600, and 900 pulse/sec) in deionized aqueous media. The results of XRD cubic symmetry for copper nanoparticles has been recorded zinc nanoparticles and that the system is hexagonal. The results of FESEM indicate obtaining the average size of diameters (42, 28, and 16 nm) respectively for CuNP. We average the size of diameters (48, 32, and 22nm) respectively for ZnNP. Through Uv-Vis spectra was the surface plasmon resonance was determined two peaks were obtained at (297, 295, and 297 nm) and (652, 658, and 655 nm) for CuNP and peaks at (297, 301, and 300 nm) for ZnNP respectively, as for the energy gap, its values were (3.067 eV, 3.074 eV, and 3.16 eV) respectively, for CuNP, and (3.201 eV, 3.247 eV, and 3.28 eV) respectively for ZnNP. These findings have significant implications for various industrial and electronic applications involving these materials. [ABSTRACT FROM AUTHOR]

When neutrinos are influenced by the presence of Earth matter, they provide new possibilities to explore the Earth's interior. The MSW Effect on the oscillations of low energy (MeV to GeV) neutrinos is exploited in a number of ways, from arrangements based on high energy neutrinos' interactions with Earth matter to methods based on high energy neutrinos' interactions with Earth matter. Neutrinos can hypothetically be launched from a variety of etymologies (sun, air, supernovae, plasma, and so on). We summarize and analyze extraordinary methods in this conversation, with a focus on later occurrences. We also discuss additional geophysical angles that are important for neutrino oscillations. It's the result of switching from one neutrino assortment to another in a medium with varying density. The massive mixing MSW effect is realized within the Sun, resulting in the correct reaction to the solar neutrino issue. The small mixing MSW effect caused by the 1-3 mixing is most often recognized for supernova (SN) neutrinos. Innovative aspects of MSW can manifest within disintegrating galaxies, such as non-oscillatory transition, non-adiabatic transition, and time-dependent adiabatic violations triggered by explosion waves. For atmospheric and accelerator neutrinos, the effects of resonance strengthening and hence multivariate stimulation of fluctuations are frequently determined inside the Earth. The attenuation effect is approximated using a special solution for neutrino oscillations in a low-density medium with variable density. The world's largest universe achievement is stellar and supernova neutrinos, thus the observations are significant for neutrino oscillation imaging. [ABSTRACT FROM AUTHOR]

The cavity that is formed between the ITER ICRF antenna plug and its port can exhibit resonances at specific fre-quencies, some of them in the relevant range of frequencies for IC heating. These resonances related to eigenmodes of the coaxial cavity, can substantially increase the level of electric fields inside the cavity and the level of RF losses in the B4C neutron shielding tiles at the back of the port-plug cavity can also be significant. For instance, in MWS simulations of a simplified geometry of the antenna in front of a dielectric mimicking the plasma loading, the level of RF losses in the B4C can reach tens of kW in 00ππ toroidal phasing and even larger values in monopole. RF probes will be installed to monitor the RF fields in the port plug cavity and additional simulations are required to properly assess the integration (position, orientation) and their effectiveness. A model with a very detailed geometry of the antenna was also used in Ansys HFSS and TOPICA simulations. On the one hand it is observed that the resistivity of the B4C neutron shielding material located at the back of the cavity has a marked effect on the excitation of the resonances and that for certain ranges of resistivity the numerical computation fails exhausting computer memory requirements (Ansys/HFSS) when trying to solve the total antenna and cavity problem as a single model. On the other hand lossy materials such as the B4C tiles cannot be represented in TOPICA models while a realistic plasma gyrotropic load can not be simulated in HFSS/MWS. Therefore, we introduced a modal analysis in the cavity to decouple solving the computationally intensive plasma-facing front of the launcher from the cavity. The fields computed by TOPICA for various loading conditions and frequencies are evaluated on a set of vertical planes in the cavity and expanded in a series of modal eigenmodes for a given mode of operation. This provides the necessary input for an accurate evaluation of the RF fields in the cavity in an independent model not including the antenna front-face. It will also contribute to the understanding of the impact of the relative toroidal phasing of the strap currents on the excitation of the cavity modes and to simulate accurately the response of the cavity RF probes. [ABSTRACT FROM AUTHOR]

The scientific article investigates the illumination of a homogeneous non-polar medium without an inversion center, which leads to the appearance of a stationary photovoltaic current. The direction of this current is associated with the polarization of the electromagnetic field by a tensor of the third rank and does not depend on the wave vector. The practical significance lies in the construction of mathematical models for the region of impurity-band transitions, which are determined by the asymmetry of the ionization probability of impurities due to the presence of multipole moments in the electric charge distribution. For the region of interband optical transitions, the photovoltaic effect is due to the Coulomb interaction between a hole and an electron. The application of an alternating voltage to a conducting medium that does not have an inversion center is accompanied by the appearance of a stationary photocurrent associated with the scattering asymmetry. Investigation of the photovoltaic effect at spin resonance can be considered as a method for measuring the band parameters. [ABSTRACT FROM AUTHOR]

In this study, the performance of an OWC (oscillating water column) wave energy converter device is investigated under the irregular incident waves. Two different bottom profiles in the OWC device region such as (i) smooth underwater shoal and (ii) doubly periodic bottom bed are considered in the present study. To model the irregular waves, the spectrum for the incident wave energy is considered. The well-known Bretschneider Spectrum is taken as the incident waves spectrum. The associated BVP is solved using a coupled boundary element - eigenfunction expansion method. The effect of irregular water waves and bottom undulations on the performance of the OWC device is analyzed in a detailed manner. Effect of resonance phenomena on the efficiency of the OWC device is also analyzed. [ABSTRACT FROM AUTHOR]

Slender and lightweight structures, which are prone to all kinds of vibration, require vibration absorbers of various types. They are usually pendulum- or ball-type passive absorbers, which utilize the auto-parametric resonance for their damping effect. Introduction of devices of this type into the analysis increases the complexity of the computational model which in fact, consequently, propagates into complicated properties of the response. In this paper, a wind driven stochastic response of anaeroelastic structure is used to study the effects of stochastic and mechanical interactions of natural modes. The model describing the slender structure is considered to be linear self-adjoint with non-proportional damping due to both the material of the structure and the presence of a vibration absorber. Although the additive random excitation is supposed to be continuously distributed, the general (spatial) discretization procedure is able to unify the continuous and lumped mass model approaches. The presented methodology enables the study of both mechanical and stochastic interactions of individual eigenmodes which occur within the structure. On the example of a real tower it is shown that neglect of either type of interaction can lead to results which are incompatible with a real structure. [ABSTRACT FROM AUTHOR]

In this work, silver nanoparticles (Ag NPs) were deposited on a heated glass substrate by using thermal evaporation technique without any additional annealing process. Ag NPs show stronger plasmonic increment of photoluminescence in comparison with other noble metals. The characterization techniques such as SEM, XRD, and UVVis. were used to analyse optical and morphological studies of these deposited metal NPs. Growth of nanospheres in Ag thin films were revealed by SEM. The substrate temperatures were varied from 150°C, 250°C to 350°C. Under some conditions, the Ag NPs exhibit a broad absorption in visible region. This is attributed to their LSPR effect i.e. Localized Surface Plasmon Resonance effect. Here, substrate temperature is the key parameter for controlling Ag NPs size and shapes. [ABSTRACT FROM AUTHOR]

The deposition of gold-silver (Au-Ag) nanoparticles on zinc oxide (ZnO) nanorods was successfully done via a one-pot hydrothermal method. The X-ray diffraction (XRD) spectra and Field Emission Scanning Electron Microscopy (FESEM) images showed that the ZnO nanorods had a hexagonal wurtzite crystal structure and the Au-Ag nanoparticles were face-center-cubic crystal spherical-shaped with a diameter ranging from 10 nm to 100 nm. The localized surface plasmon resonance effect of Au-Ag nanoparticles may induce the enhancement absorption in a visible region and also slightly decrease the band gap energy of ZnO nanorods. The room temperature photoluminescence spectra showed that intensity decreased in the range of 370–700 nm due to the decrease in the exciton recombination effect of the ZnO nanorods after deposition of the Au-Ag nanoparticles. The presence of Au-Ag nanoparticles also slightly enhanced the photodegradation rate of methyl blue; this may be because the photoexcited electrons of ZnO were trapped in the Au-Ag nanoparticles, which hinders the recombination of the charge carriers in ZnO and enhances the generation of free radicals for degradation of methyl blue at pH of 5.0 under ultraviolet (UV)-light irradiation. [ABSTRACT FROM AUTHOR]

In this paper we present a comparative study on the stochastic resonance in micro/nano cantilever resonators due to fluctuations in the fundamental frequency or the damping coefficient. Considering DC+AC electrostatic actuation in the presence of zero-mean Gaussian noise with exponential autocorrelation we analyze stochastic resonance behaviors for the frequency and the damping fluctuations separately, and compare the effects of stochastic resonance on Q-factor of the resonators for different levels of damping losses. It is found that even though the stochastic resonance occurs for both types of fluctuations, only the damping fluctuation produces right cooperative influence on the fundamental resonance that improves both the amplitude response and the quality factor of the resonator. [ABSTRACT FROM AUTHOR]

We study the many-body interaction between a D* and multi-ρ using the Fixed Center Approximation of the Faddeev equations. We use an extrapolation to SU(4) of the hidden gauge formalism. We select the f²(1270) and D*2(2460) states which come from ρρ and ρD* interaction, respectively. Then let a third particle, ρ, D*, or a resonance collide with them. We find several new charmed resonances, D*3, D*4, D*5 and D*6, which are not yet listed in the PDG. [ABSTRACT FROM AUTHOR]

The COMPASS Collaboration has accumulated the world's highest statistics on the reaction π-p→π+π-π-p at 190 GeV/c. The results, presented in Section 1, show that a new state JPC = 1++ state never reported before, the a¹(1420), decaying to f0(980)π followed by f0(980) → ππ. In addition, the Collaboration reports an exotic JPC = 1-+ state, the π1(1600), which cannot be a quarkonium. Both states are likely to be a tetra-quark, i.e. q...+q... or a gluonic hybrid, a q... object with an excited gluon inside it. Section 2 is devoted to a brief discussion of the central production of resonances, which is being investigated by both COMPASS and ALICE collaborations. However, the results are not yet released, so it is limited to a broad discussion of the central production, with emphasis on different analyses dictated by differences in the experimental setup. [ABSTRACT FROM AUTHOR]