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Studying the ability of atom-photon interactions, especially in two two-level atomic systems, to generate quantum information resources has recently become an important research topic in quantum information science. Therefore, this paper explores the ability of two moving atoms coupling with a coherent field through a two-photon transition to generate atomic quantum correlations by using local quantum uncertainty (LQU), local quantum Fisher information (LQFI) as well as logarithmic negativity (LN). Schrödinger equation is used to obtain the time evolution of the atom-cavity-atom interactions with an initial coherent cavity state and an initial atomic uncorrelated pure state. The generation of atomic LQU, LQFI, and LN correlations are exactly examined under the unitary interaction parameter effects, including the atom-cavity coupling strengths, the cavity field half-wave number, and the initial coherent state intensity. The atom-cavity-atom interaction parameters lead to notable changes in the amplitudes, speed, and regularity of the LQU, LQFI, and LN dynamics, which can be enhanced by increasing the initial coherent intensity. The cavity field half-wave number leads to generating atomic quantum correlations with regular oscillatory behavior. The sudden death-birth phenomenon of the logarithmic negativity depends on the atom-cavity-atom interaction and the atomic location parameter. [ABSTRACT FROM AUTHOR]

In this paper, an intrinsic decoherence model is solved analytically for a Λ -type qutrit interacting with a coherent field through intensity-dependent coupling. The effects of the qutrit-cavity interaction, the intrinsic decoherence and the initial coherent field intensity are examined on some quantum phenomena as: atom population inversion, mixedness, entanglement as well as total correlation. It is found that the increase of the physical parameters, the regular oscillatory behavior of the qutrit-population collapses and revivals are changed remarkably. The interaction between the three-level atom and the coherent cavity field generates a strong mixture, negativity entanglement and total correlation (classical + quantum). The growth, the regularity and the stability of these quantum effects depend on the decoherence and the initial coherent cavity intensity. [ABSTRACT FROM AUTHOR]

Abstract Recently, sparse representation has attracted a great deal of interest in many of the image processing applications. However, the idea of self-similarity, which is inherently present in an image, has not been considered in standard sparse representation. Moreover, if the dictionary atoms are not constrained to be correlated, the redundancy present in the dictionary may not improve the performance of sparse coding. This paper addresses these issues by using orthogonal moments to extract the correlations among the atoms and group them together by extracting the characteristics of the noisy image patches. Most of the existing sparsity-based image denoising methods utilize an over-complete dictionary, for example, the K-SVD method that requires solving a minimization problem which is computationally challenging. In order to improve the computational efficiency and the correlation between the sparse coefficients, this paper employs the concept of overlapping group sparsity formulated for both convex and non-convex denoising frameworks. The optimization method used for solving the denoising framework is the well known majorization–minimization method, which has been applied successfully in sparse approximation and statistical estimations. Experimental results demonstrate that the proposed method offers, in general, a performance that is better than that of the existing state-of-the-art methods irrespective of the noise level and the image type. Highlights • We propose the use of Orthogonal moments as similarity measure in dictionary learning based image denoising. • The concept of overlapping group sparsity (OGS) is employed to promote strong correlation between sparse coding coefficients. Further, OGS is used in solving both convex and non-convex optimization problems. • The grouping of the similar patches in an image is proposed using L 2 norm-based similarity criterion evaluated using Krawtchouk and Tchebichef moments. The advantage of using moment domain-based similarity measure over L 2 norm is increased noise robustness. • The proposed image denoising framework is solved using majorization–minimization optimization framework used widely in signal processing. [ABSTRACT FROM AUTHOR]

In greedy pursuit algorithm, atom selection is commonly a concerned topic for signal compressed recovery. To improve the recovery performance, an optimal atom selection strategy without the prior information is proposed in this paper. The sensing information entropy is defined to prune the possible false atoms in the estimated support set. Fewer iterations are required in the proposed strategy and it can also be applied in the case with high sparsity level or low signal-noise-ratio. Compared with the existing representative algorithms, the superiority of the recovery error and probability is verified by the simulations. Furthermore, the proposed method is applied to recover the real random modulated signal. The results show that the recovered signal has greater consistence with the original input signal. • An atom selection strategy without prior knowledges is proposed. • Sensing information entropy is defined to realize pruning of the false atom. • The proposed strategy can be applied in the low signal-noise-ratio environment. • The signal recovery can be achieved successfully with fewer iterations. [ABSTRACT FROM AUTHOR]

• The exact expression of atom-atom field wave function is obtained. • The strong effect of Stark shift and Kerr medium on the atomic entropy is found. • The geometric phase in the time-dependent system is compared with the time-independent system. • The sensitivity of the geometric phase to the time-dependent coupling parameter is higher than that in the atomic entropy. In this paper, two-level atoms interacting with a single-mode radiation field alongside important properties are presented. The model presented discusses multi-photon process and it has also a nonlinear Kerr-medium and Stark-shift. In addition, the coupling parameter is discussed in a time-dependent fashion. The results show that Stark-shift, time-dependent coupling parameter, and nonlinear Kerr-medium play significant roles regarding the evolution of the von-Neumann entropy and the system's geometric phases. We've used accessible parameters to examine these observations, and some new results are obtained. Remarkably, the geometric phase shows high sensitivity to any change of the considered parameters. [ABSTRACT FROM AUTHOR]

The Sc atom is particularly significant role in the ScAl 2 O 2 − activating methane C H bond, so the creation of H 2 suggests that the importance of the "support" cluster cannot be overlooked. In the reaction of C H activated by Sc atom, the energy of the single state is lower than that of the triplet state. There is an orbital drill-through effect, in which the single state is the major channel of the reaction. ScAl 2 O 2 − catalyzes the activation of CH 4 to get the H 2 , which serves as a candidate for the production of new energy. [Display omitted] Due to its thermochemical stability, CH 4 is generally difficult to be dissociated. In this paper, the role of Sc atom in the results of the C H bond activation operation was investigated using the DFT-D (M06-2X) method to understand the reaction process. It was discovered that the double low-spin state Sc atom easily react with CH 4 , whereas the high-spin ground state Sc is inert. The mechanism of the supported ScAl 2 O 2 − activated CH 4 and the free Sc reaction system are extremely similar. The major channel is the low-spin state, displaying the incidence of spin flipping has an orbital drill-through effect. In the ScAl 2 O 2 − reaction, the Al 2 O 2 − anion can efficiently support Sc atom and thereby activate CH 4 while also imparting its high reactivity to the supported Sc. In the future, it will be possible to examine the role of the Sc atom in the catalytic activation process of ScAl 2 O 3 − on CH 4. [ABSTRACT FROM AUTHOR]

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Counting neutrons emitted by special nuclear material (SNM) and differentiating them from the background neutrons of various origins is the most effective passive means of detecting SNM. Unfortunately, neutron detection, counting, and partitioning in a maritime environment are complex due to the presence of high-multiplicity spallation neutrons (commonly known as "ship effect") and to the complicated nature of the neutron scattering in that environment. A prototype neutron detector was built using 10B as the converter in a special form factor called "straws" that would address the above problems by looking into the details of multiplicity distributions of neutrons originating from a fissioning source. This paper describes the straw neutron multiplicity counter (NMC) and assesses the performance with those of a commercially available fission meter. The prototype straw neutron detector provides a large-area, efficient, lightweight, more granular (than fission meter) neutron-responsive detection surface (to facilitate imaging) to enhance the ease of application of fission meters. Presented here are the results of preliminary investigations, modeling, and engineering considerations leading to the construction of this prototype. This design is capable of multiplicity and Feynman variance measurements. This prototype may lead to a near-term solution to the crisis that has arisen from the global scarcity of ³He by offering a viable alternative to fission meters. This paper describes the work performed during a 2-year site-directed research and development (SDRD) project that incorporated straw detectors for neutron multiplicity counting. The NMC is a two-panel detector system. We used I0B (in the form of enriched boron carbide: wB4C)for neutron detection instead of3He. In the first year, the project worked with a panel of straw neutron detectors, investigated its characteristics, and developed a data acquisition (DAQ) system to collect neutron multiplicity information from spontaneous fission sources using a single panel consisting of 60 straws equally distributed over three rows in high-density polyethylene moderator. In the following year, we developed the field-programmable gate array and associated DAQ software. This SDRD effort successfully produced a prototype NMC with ~ 33% detection efficiency compared to a commercial fission meter. [ABSTRACT FROM AUTHOR]

In this paper we investigated the entanglement dynamics of a pair of two-level atoms passing through a vacuum or thermal cavity one after another. We assumed that two atoms were initially prepared in separable coherent or entangled states. Using the exact solution of the density matrix evolution equation we calculated the time dependence of negativity for models with one-and two-photon interaction between atoms and the cavity field. For the two-photon model we took into account the dynamical Stark shift. We have found that the degree of atom-atom entanglement can be controlled by the Stark shift and cavity mean photon numbers. [ABSTRACT FROM AUTHOR]

Abstract: The belief among investigators of the Casimir effect is that it is conservative and that the two interpretations as to the source of energy behind the Casimir effect are equivalent. In the first, the energy source is considered to be the zeropoint fields in the vacuum of space between the plates. In the second, the source is considered to come from the potential energy of atoms in the bulk matter making up the plates. The bulk matter interpretation will be trivially conservative because the plates comprise a closed system. The vacuum energy interpretation is not as clear. If the zero-point fields between the plates are static, the system will be closed and the forces will be conservative. However the fields may be a dynamic steady state in which case the system could be open and the forces not conservative. This paper examines a plausible but speculative extension of the vacuum centric proximity force approximation that incorporates the local geometry of non-parallel plates. This inclusion eliminates problems of local scale nonsensical distances between plates as well as some absurd results but introduces non-conservative forces. While only an experiment or more fundamental analytic approach can determine whether Casimir forces are conservative, the purpose of this paper is to merely raise the question. [Copyright &y& Elsevier]

Abstract: In this paper a new model is presented for calculating the atomic physics of atoms in hot and dense plasmas – the Ion Ellipsoid Model (IEM). The basic assumption of the model is that the ion is confined in an ellipsoid enclosure, with the total electric field vanishing on and beyond the ellipsoid surface. Ellipsoid shapes approximate the Voronoi cells of the ions. The present paper describes the statistical distributions of the ellipsoids'' shapes and sizes, and the ion location relative to the ellipsoid center. Simple high accuracy semi-empirical formulas are presented for the probability densities of these quantities. The results indicate an increasing spherical symmetry around the ions and a significant reduction in the symmetry fluctuations as the plasma coupling constant, Γ, increases, in accordance with intuitive expectations. IEM predicts a fluctuating continuum lowering and thereby provides a realistic description of the situation in real plasmas. An explicit expression is provided for the distribution function of the continuum lowering. At high Γ''s the average continuum lowering approaches the value given by the Ion Sphere Models. The electric fields at the ions, as computed with the IEM, turn out to be too low relative to those obtained directly from the Monte Carlo computations. A simple Γ-dependent scaling factor can, however, bring the IEM electric field distributions into good agreement with the Monte Carlo results. [Copyright &y& Elsevier]

The process and the entity concepts in chemistry and in physics (with a few words to the same concepts in biology) have been analysed. A first aspect underlined in this paper is the relativity of these two concepts and their relations to the time-scales and to the measurement devises. In mechanics "an object in transformation" can be studied by the help of a differentiation between the "system variables", that they identify the system, and "configuration (or state) variables", that they describe the dynamical state of the system. Instead, in chemistry an entity is an object with characteristic properties (static and dynamical) so particular than it has a proper name. There are entities in both the macroscopic (chemical substances) and the microscopic world (molecules and atoms). A fundamental point underlined in the paper is that in the chemistry picture they exist million of these different objects. It is this complex world the material of the chemical explication of both inanimate and animate things. Also the process concept is different in chemistry and in physics. In the paper we analyse the different interpretation of the substance transformation (reactivity) in these two disciplines: in physics this is considered a modification of the equilibrium condition of a system, due to a perturbation; in chemistry a modification of the system, due to the "death" and the "birth" of different substances. The couple transformation/ transition can identify the point of view of the physics and the chemistry about the substance modification. An important point underlined in the paper is that in the conceptual movement from the physics to the chemistry (and, finally, to the biology) the importance of the entity concept increases and that of the process concept decreases. The entity and process concepts generate in physics and in chemistry two different explanations: the first based on the law and the second on the presence in the system of individual entity and on their properties. In the paper we underline that this implies two different approaches to the material world: that of the physics and that of the chemistry. Two general consequences are shown in the paper: the first about the relation between the chemistry and the physics and the second on the reductionism and about the inanimate-animate and animal-man dichotomies. [ABSTRACT FROM AUTHOR]

The article presents abstracts of papers related which are to be presented at the Fiftieth Annual Meeting of the Health Physics Society in Spokane, Washington on July 14, 2005. The paper " Accelerator Shielding Design: From Protons to Electrons, from America to Europe and Back," discusses that an important role in the technical progress in this field has been played by a long-standing collaboration between the Radiation Protection Groups of European Center for Nuclear Research and Stanford Linear Accelerator Center, respectively the largest proton and electron accelerator centers in the world. Such collaboration, informal and unofficial, has developed over many years as a result of frequent exchanges of experts and of know-how between the two laboratories, which is still continuing today. The paper "Updating the Department of Energy Accelerator Safety Order and Guide," discusses that the Department of Energy (DOE) Accelerator Safety Order, DOE O 420.2B, was reissued in July 2004. The order was first issued in November 1992 and reissued in 1998 and 2001 to reflect progress in the DOE approaches to assuring safe operations at accelerator facilities.

Multiscale simulation approaches are needed in order to address scientific and technological questions in the rapidly developing field of carbon nanotube electronics. In this paper, we describe an effort underway to develop a comprehensive capability for multiscale simulation of carbon nanotube electronics. We focus in this paper on one element of that hierarchy, the simulation of ballistic CNTFETs by self-consistently solving the Poisson and Schrödinger equations using the nonequilibrium Green's function (NEGF) formalism. The NEGF transport equation is solved at two levels: i) a semiempirical atomistic level using the p&z orbitals of carbon atoms as the basis, and ii) an atomistic mode space approach, which only treats a few subbands in the tube's circumferential direction while retaining an atomistic grid along the carrier transport direction. Simulation examples show that these approaches describe quantum transport effects in nanotube transistors. The paper concludes with a brief discussion of how these semiempirical device-level simulations can be connected to ab initio, continuum, and circuit level simulations in the multiscale hierarchy. [ABSTRACT FROM AUTHOR]

To use these detectors in the optimal way and to determine their detection characteristics, detailed calibration studies of the selected plastic detectors, and especially CR-39 and PM355 types have been performed at IPJ for several years. The paper presents detection characteristics, i.e. track diameters as a function of ion energy, atomic number and etching time. There are also presented in the paper different applications of the detectors in question, particularly in the Plasma Focus experiments. [ABSTRACT FROM AUTHOR]

Various nanomaterials (NMs) with special characteristics such as high reactivity, improved catalysis, and adsorption properties have gained considerable attention to improve the performance and characteristics of membranes especially in the field of wastewater treatment. Engineered nanoscale zero-valent metals (nZVMs) and metal single atoms (MSAs) indicate the superior performance in membrane technologies, due to their cost-effectiveness of production and strong catalytic capability in the removal of pollutants. This paper critically reviews the nZVMs and MSAs incorporation in membranes processes with considering the different features of the bare, supported, or modified nanomaterials and bimetallic systems. Various fabrication techniques of nZVMs modified membranes including phase inversion, interfacial polymerization, blending in the coated layer, and other fabrication methods were summarized. Nanoscale zero-valent iron (nZVI) as the most extensively studied nZVMs, due to their low cost and effective properties in the removal of pollutants were highlighted and different applications of those in membrane processes as a reactive medium for wastewater treatment focusing on polymeric membrane systems were discussed. Furthermore, the effects of numerous nZVMs and MSAs used in membrane processes and various supporting techniques were explained and the key factors of the different operation conditions for contaminants removal are critically compared. Also, an account of dynamic simulations of MSAs applications in different membrane processes and future research directions based on the findings have been reviewed throughout the study. [Display omitted] • Review of nanoscale zero-valent metals (nZVMs) and metal single atoms (MSAs) in membrane technologies. • Review of nZVMs and MSAs incorporation in membranes fabrication and modification. • Highlighting the application of nanoscale zero-valent iron (nZVI) in membrane processes. • Dynamic simulations of MSAs applications in different membrane processes. • Future research directions of nZVMs and MSAs in membrane science and Technology. [ABSTRACT FROM AUTHOR]

Abstract: Based on the density functional theory (DFT), the intramolecular methyl transfers in a series of 2-methoxy-pyridine derivative radical cations have been analyzed in this paper. The calculations indicate that all the methyl migrations are exothermic and the corresponding reaction enthalpies vary from −5.3 to −17.5kcal/mol. In kinetics, the activation enthalpies vary from 35.9 to 48.9kcal/mol. The electron-withdrawing substituting groups could promote the intramolecular methyl transfer, while the electron-donating substituting groups have the opposite effect. Meanwhile, the effects of substituting groups adjacent to the nitrogen atom are most significant. The Marcus theory analyses indicate that the major driving force for the acceleration effect of the substituent is the intrinsic factor. In addition, compared with other function groups, such as ethyl, isopropyl and phenyl groups, the methyl is the most difficult to transfer from oxygen atom to nitrogen atom in our systems. [Copyright &y& Elsevier]

Abstract: This paper describes the development and use of time-dependent density functional theory (TDDFT) methods for determining surface enhanced Raman scattering (SERS) spectra, with emphasis on pyridine interacting with a 20 atom silver cluster as a model of a molecule/nanoparticle system of interest to SERS. The calculations use a new implementation of a TDDFT linear response module in a locally modified version of NWChem for the TDDFT calculations. This code enables us to explore the influence of basis set effects and different choices of density functionals on the Raman spectra, including studies of correlation-consistent basis sets, and of hybrid density functionals. Previous work had employed the BP non-hybrid GGA functional, which works already quite well. Hybrid-GGA functionals such as B3LYP are better at reproducing the experimental spectra of the pyridine silver complex. However for relatively inexpensive calculations, the combination of BP with the DZVP basis set is able to provide semi-quantitative accuracy at reasonable cost, especially in conjunction with an appropriate pseudopotential for the silver atom. [Copyright &y& Elsevier]

Abstract: In this work, we report ab initio calculations, based on density functional (DFT) theory and second order Møllar–Plesset (MP2) perturbation methodology to investigate the relative stability of Si8H8−n Li n (n =0–8) clusters. The work presented in this paper is aimed at to investigate if lithium atoms are better candidates over hydrogen atoms to saturate the dangling bonds while stabilizing a three dimensional (3D) silicon cluster, such as S8, so that it can promote the same point group symmetry as in its carbon analog. Such a concept was first hypothesized by Zdetsis (J. Chem. Phys. 127 (2007) 214–306) while attempting benzene symmetry in Si6Li6 ring. The cubic Si8 cluster has been saturated both by H and Li atoms, and the sequential replacement of hydrogen by lithium atom is marked by the decrease in binding energy, HOMO–LUMO gap, ionization potential, and chemical hardness inferring that hydrogen atoms are preferable candidates over lithium atoms for the stabilization of 3D Si8 cluster. In addition, it is observed that both H and Li atoms, induce cubane symmetry (Oh) in 3D Si8 cluster provided that they undergo terminal bondings with Si atoms. On the other hand, Li atoms placed at the bridge sites are found to distort the structure of Si8 from the cubane symmetry. [Copyright &y& Elsevier]

Abstract: In this paper we present the electronic and structural study of beryllium molecules analogous to crown ethers, where the –CH2– groups have been exchanged for beryllium atoms. The resulting structures are completely planar, unlike crown ethers, that the latter are bi-dimensional and flexible. In addition, the coordination of lithium atoms (as Li+), which are arranged directionally to each oxygen atom, are able to accommodate in its coordination sphere from three to four hydrogen molecules. We also evaluated the binding energy between lithium complexes and hydrogen molecules in each structure with the same method. [ABSTRACT FROM AUTHOR]

This paper advocates re-focusing interaction design towards aesthetics and compositions. Inspired by current movements within humancomputer interaction, product design, materials science, and architecture, we argue that a central problematic concerned with reconciling the digital and physical has always shaped the field. Rather than bridging atoms and bits, an approach that systematically keeps the digital and physical apart, we advocate thinking of design as composition. Doing so will require articulating an aesthetic vocabulary that formally relates diverse materials whether digital or physical. Texture, a word that applies across materials, substrates, and scales, is advanced as a candidate term within our approach. We provide a model for thinking about texture as a relation and then ground the model through a design project, Icehotel X, rendered in ice and digital displays. Texture guided the quality of composition achieved in the final design executed by a team of diverse experts. This approach opens new avenues for the analysis and practice of interaction design. [ABSTRACT FROM AUTHOR]

In this paper, we synthesize active carbon samples with various content of nitrogen and oxygen of heteroatoms, as well as surface functional groups. We determine the specific surface area and porosity of the obtained carbon, study its behaviour in the model oxide reduction processes, notably electrochemical oxygen reduction and catalytic decomposition of hydrogen peroxide. Relying on the data analysis, we characterize the impact of surface chemistry and porosity on the electron-donating ability of nitrogen and oxygen containing active carbons. We take the perspective that this carbon can be applied as a fuel cell electrocatalyst. [ABSTRACT FROM AUTHOR]

Given an amino acid sequence with the a-carbon 3D coordinates on its backbone, the all-atom protein backbone reconstruction problem (PBRP) is to rebuild the 3D coordinates of all major atoms (N, C and O atoms) on the backbone. In this paper, we first build a 4-residue fragment library extracted from PDB. Then, to solve PBRP, we search for fragments with similar structures based on the inner distances. To test the performance of our method, we use two testing sets of target proteins, one was proposed by Maupetit et al. and the other is a subset extracted from CASP7. We compare the experimental results of our method with three previous works, MaxSprout, Adcock's method and SABBAC proposed by Maupetit et al. The reconstruction accuracy of our method is comparable to these previous works. And the solution of our method is more stable than the previous works in most target proteins. These previous works contain complicated energy computation, while our method does not. Thus, our method requires much less execution time than the previous works. [ABSTRACT FROM AUTHOR]

A protocol to generate disordered structures of lithiated Si was recently developed to reproduce the experimental potentialcomposition curve of a-Si lithiation at room temperature. In this paper, the bond angle distributions of these structures were studied, showing results consistent with the literature. Charge transfer studies using Bader charge analysis indicate that Li atoms donate 0.7 electrons to Si atoms, as in crystalline phases. The local environments of Si and Li atoms were shown to have a large impact on charge transfer as evaluated by considering neighbors through the effective coordination model. The variation in the effective Li neighbors with composition provides an insight into the cause of the drop in potential, which is observed in the experimental potential-composition curves of a-Si lithiation near Li2Si. The evolution of the electronic density of states with lithiation was studied, showing behaviors similar to crystalline phases. The limitations of the protocol are discussed in relation to diffusion effects and bond-breaking activation energies. By approximating the lithiation of crystalline Si and the delithiation of Li15Si4 as two-phase reactions, calculated potential plateau values were obtained, having a reasonable agreement with experiment (∼0.1 V). [ABSTRACT FROM AUTHOR]

In this paper, we propose several approaches for estimation of adhesion energy of cooperating surfaces at thermodynamic and electron-statistical plasma spraying. We also analyze and calculate basic physical parameters, responsible for increasing a number of atomic bonds and adhesive strength by using the theory of chemical kinetics. These atomic bonds participate in contact interaction of the basis atoms and corpuscles. [ABSTRACT FROM AUTHOR]

New neutron production cross sections of tungsten isotopes such as 182W, 183W, 184W, and 186W have been validated through shielding benchmarks and criticality safety benchmarks with the MCNPX-2.5.0 code. The calculation results based on the new evaluations have been compared with those based on ENDF/B-VII.0, JEFF-3.1, JENDL-3.3, and FENDL-2.1 as well as the benchmark experiments. In this paper, some noticeable improvements in calculations of the neutron leakage spectra from tungsten shields and the keff's for critical assemblies with tungsten are presented. [ABSTRACT FROM AUTHOR]

The second is currently defined by the microwave transition in cesium atoms. Optical clocks offer the prospects of stabilities and reproducibilities that exceed those of cesium. This paper reviews the progress in frequency standards based on optical transitions, recommended by International Committee for Weights and Measures, as a secondary representation of the second. The operation of these standards is briefly described and factors affecting stability and accuracy of these and some new optical clocks are discussed. [ABSTRACT FROM AUTHOR]

An investigation of the proton dynamics inside a Nafion membrane has been carried Out by molecular dynamics simulations. The atomistic analysis was performed at four different hydration levels (4.21, 8.61, 12.65, and 21.60 wt %) and three operation temperatures (333, 343, and 353 K). The simulation results show a distinct ionic segregation toward the hydrophobic (near fluorocarbon) and hydrophilic (close to the sulfonated acid groups) regions inside the membrane. The number of water clusters at high hydration levels increases significantly compared to the lower cases. A higher temperature tends to magnify the size of the hydrophilic phase; both increase the proton diffusivity. Apart from the effect analysis, this paper also explains the nanoscopic mechanism of the proton transport and further relates it to the molecular structure of the electrolyte membrane. [ABSTRACT FROM AUTHOR]

The characteristics of atomic layer deposited (ALD)-Al2O3 gate dielectrics with CF4 plasma surface treatment have been studied in this paper. Fluorine atoms were observed to be incorporated at bulk Al2O3 and pile-up at both Al/Al2O3 and Al2O3/Si interfaces. X-ray photoelectron spectroscopy analysis demonstrated that Al-O bonds were replaced by Al-F and F-Al-O bonds as samples were treated in CF4 plasma. A physical model was proposed to explain the capacitance-equivalent-thickness (CET) degradation and capacitance-frequency-dispersion phenomenon. The CF4 plasma-treatment approach can immunize capacitance dispersion due to its excellent capability of interface trap passivation by fluorine atoms in Al2O3 dielectrics. Fluorine incorporation was proven to improve the Al2O3 dielectric characteristics of hysteresis oxide reliability and capacitance dispersion. [ABSTRACT FROM AUTHOR]

In this paper, we present two alternative approaches to defining answer sets for logic programs with arbitrary types of abstract constraint atoms (c-atoms). These approaches generalize the fixpoint-based and the level mapping based answer set semantics of normal logic programs to the case of logic programs with arbitrary types of c-atoms. The results are four different answer set definitions which are equivalent when applied to normal logic programs. The standard fixpoint-based semantics of logic programs is generalized in two directions, called answer set by reduct and answer set by complement. These definitions, which differ from each other in the treatment of negation-as-failure (naf) atoms, make use of an immediate consequence operator to perform answer set checking, whose definition relies on the notion of conditional satisfaction of c-atoms w.r.t. a pair of interpretations. The other two definitions, called strongly and weakly well-supported models, are generalizations of the notion of well-supported models of normal logic programs to the case of programs with c-atoms. As for the case of fixpoint-based semantics, the difference between these two definitions is rooted in the treatment of naf atoms. We prove that answer sets by reduct (resp. by complement) are equivalent to weakly (resp. strongly) well-supported models of a program, thus generalizing the theorem on the correspondence between stable models and well-supported models of a normal logic program to the class of programs with c-atoms. We show that the newly defined semantics coincide with previously introduced semantics for logic programs with monotone c-atoms, and they extend the original answer set semantics of normal logic programs. We also study some properties of answer sets of programs with c-atoms, and relate our definitions to several semantics for logic programs with aggregates presented in the literature. [ABSTRACT FROM AUTHOR]

In an earlier paper [1] the relation σB = σ∞ + const, tB-1/4 has been deduced for the time dependence of the strength decrease under a static load. In the formula σ∞ means the fatigue limit and σB is the stress causing a fracture after the loading period tB. By application of this formula the activation energy of the static fatigue of glass and of the creep of steel is calculated from experimental data at different temperatures. The activation energy determined for steel corresponds to activation energy for the diffusion of sulfur in iron but corresponds also to the half of the sublimation enthalpy for iron. Therefore, the rate limiting step of the creep of steel at elevated temperatures may be a diffusion of interstitial atoms as well as a quasi-sublimation. A theoretical model is given for the defect growth due to a quasi-sublimation. [ABSTRACT FROM AUTHOR]

This paper presents a systematic characterization of hydrogen capacitively coupled very high frequency discharges, produced within a parallel plate cylindrical setup, by comparing numerical simulations to experimental measurements for various plasma parameters. A good quantitative agreement is found between calculation and experiment for the coupled electrical power and the plasma potential, at various frequencies, pressures and applied voltages. However, the model generally underestimates the electron density and the self-bias potential with respect to measured values. Model predictions for the absolute density of H(n=1) atoms are compared to first diagnostic results, obtained by two-photon absorption laser-induced fluorescence diagnostics at various pressures and frequencies. [ABSTRACT FROM AUTHOR]

The theoretical and experimental researches of electron behavior in MPFS with varying longitudinal component are given in this paper. We obtain the analytical expressions for description of electron motion in such systems. It is shown that we can effectively influence on the beam focusing avid beam passing to the collector by choosing the initial electron velocities. [ABSTRACT FROM AUTHOR]

Atom search optimization (ASO) is a newly developed metaheuristic algorithm inspired by molecular basis dynamics. The paramount challenge in ASO is that it is prone to stagnation in local optima due to premature convergence. To solve this issue, a modified atom search optimization with dynamic opposite learning and heterogeneous comprehensive learning is proposed in this paper, which is named DOLHCLASO. First, the asymmetry of dynamic opposite learning can increase the probability that the population will obtain an optimal solution, while dynamic characteristic can enrich population diversity and enhance exploration capability. Second, the heterogeneous comprehensive learning divides the population into two subpopulations, exploration-subpopulation and exploitation-subpopulation, and the division of labor and cooperation effectively balances exploration and exploitation. Finally, the proposed DOLHCLASO was evaluated in the CEC2017 benchmark functions and real-world engineering cases, compared with some classic and excellent variants of algorithms to confirm its performance. Experimental results and statistical analysis demonstrate that the performance of the DOLHCLASO is significantly better than other selected optimizers. • DOL is used to enhance the quality of initial population and overcome premature convergence. • Nonlinear weight is used to enhance DOL generation jumping. • HCL strategy is used to balance exploration and exploitation better. • Performance of the proposed DOLHCLASO was verified by CEC2017 and engineering problems. [ABSTRACT FROM AUTHOR]

This paper described the fabrication of a new Fe3O4/CdS nanocomposite. PCd(MA)2 was firstly polymerized by surface-initiated atom transfer radical polymerization (ATRP) on the surface of Fe3O4 nanoparticles, and then the formation of CdS nanoparticles took place in situ when S2- ions were released by thioacetamide upon heating. The nanocomposites were characterized by XPS, TEM, and UV-vis. The PL and magnetic properties were also studied. [ABSTRACT FROM AUTHOR]