Continuous Energies Research Articles

Unveiling reversible hydrogen storage mechanism for the 2D penta-SiCN material

The promise of using 2D materials for hydrogen storage has broad prospects, ascribe to their significant specific surface area and lightweight properties. In this work, the hydrogen storage capability and reversible storage mechanism of 2D penta-SiCN material are investigated based on the first-principles computational method. Thermal stability of penta-SiCN is calculated by the ab-initio molecular dynamics (AIMD) simulation and root-mean-square displacement (RMSD) algorithm. It has been found that penta-SiCN is thermodynamically stable even after adsorbing hydrogen molecules. Taking into account the benchmarks of average and continuous adsorption energies of the adsorption systems, a pristine 2 × 2 × 1 penta-SiCN substrate has the ability to adsorb up to 26H2 molecules, which results in a maximum hydrogen storage capacity of 10.80 wt%. According to the semi-empirical calculation method that based on the thermodynamic analysis, the penta-SiCN adsorption system has a high reversible hydrogen storage capacity of 9.57 wt% within the adsorption and desorption application working conditions. The results proposed in this study demonstrates that penta-SiCN exhibits considerable promise for hydrogen storage with its substantial hydrogen storage capacity, exceptional reversibility, and eco-friendly characteristics.

Tangent-point energies and ropelength as Gamma-limits of discrete tangent-point energies on biarc curves

Using interpolation with biarc curves we prove Γ-convergence of discretized tangent-point energies to the continuous tangent-point energies in the C^{1}-topology, as well as to the ropelength functional. As a consequence, discrete almost minimizing biarc curves converge to minimizers of the continuous tangent-point energies, and to ropelength minimizers, respectively. In addition, taking point-tangent data from a given C^{1,1}-curve γ, we establish convergence of the discrete energies evaluated on biarc curves interpolating these data, to the continuous tangent-point energy of γ, together with an explicit convergence rate.

Thermal neutron fluence measurement using a cadmium differential method at the laser-driven neutron source

We produced high-energy neutrons by p + Be and d + Be reactions with protons and deuterons with continuous energies of up to 30 and 10 MeV/u, respectively, provided from laser-plasma interactions. Thermal neutrons were subsequently generated through deceleration by a small moderator with conjunction on the Be target. Here, we report the measurements on the thermal neutron fluence using the activation method with/without Cd filters. The unstable isotopes of 198Au, 56Mn, 60Co, and 181Hf were produced through (n, γ) reactions by a single laser shot. The nuclear reaction fractions were evaluated by measuring the γ-rays emitted from these unstable isotopes. The thermal neutron fluences from the four nuclides are consistent within their experimental uncertainties. The fluence is evaluated to be (2.2 ± 0.4) × 105 neutrons cm−2 at the distance of approximately 9 mm at 90° against the laser axis. The present result shows that the method to generate thermal neutrons from a compact neutron source with a diameter of 44 mm and length of 46 mm is expected to be a useful tool for various nuclear experiments and applications.

Template molecular weight-dependent PEDOT surface energy: impact on the photovoltaic performance of bulk-heterojunctions

A simple strategy based on the template Mw effect is developed for the realization of high-performance PEDOT AIMs with continuous gradient surface energies, and we found that low surface energy donor (or acceptor) based BHJs favor low surface energy PEDOT.

CHARACTERISTICS OF THERMOMETRIC MATERIAL Lu1-xScxNiSb

CHARACTERISTICS OF THERMOMETRIC MATERIAL Lu1-xScxNiSb

Crystallographic phase changes and damage thresholds of CsPbI3 microwire waveguides through continuous wave photoablation

We investigate waveguide efficiency of CsPbI3 microwire waveguides and their photodegradation over a range of continuous wave laser excitation energies and intensities.

High Temperature Optical Spectra of Diatomic Molecules at Local Thermodynamic Equilibrium

In the paper, several theoretical approaches to the determination of the reduced absorption and emission coefficients under local thermodynamic equilibrium conditions were exposed and discussed. The full quantum-mechanical procedure based on the Fourier grid Hamiltonian method was numerically robust but time consuming. In that method, all transitions between the bound, free, and quasi-bound states were treated as bound–bound transitions. The semi-classical method assumed continuous energies of ro-vibrational states, so it did not give the ro-vibrational structure of the molecular bands. That approach neglected the effects of turning points but agreed with the averaged-out quantum-mechanical spectra and it was computer time efficient. In the semi-quantum approximation, summing over the rotational quantum number J was done analytically using the classical Franck–Condon principle and the stationary–phase approximation and its consumption of computer time was lower by a few orders of magnitude than the case of the full quantum-mechanical approach. The approximation described well the vibrational but not the rotational structure of the molecular bands. All the above methods were compared and discussed in the case of a visible and near infrared spectrum of LiHe, Li2, and Cs2 molecules in the high temperature range.

Geodesic distance Riesz energy on the sphere

We study energy integrals and discrete energies on the sphere, in particular, analogues of the Riesz energy with the geodesic distance in place of the Euclidean, and we determine that the range of exponents for which uniform distribution optimizes such energies is different from the classical case. We also obtain a very general form of the Stolarsky principle, which relates discrete energies to certain L 2 L^2 discrepancies, and prove optimal asymptotic estimates for both objects. This leads to sharp asymptotics of the difference between optimal discrete and continuous energies in the geodesic case, as well as new proofs of discrepancy estimates.

Orta Asya Ülkelerinde Elektrik Enerjisi, Doğrudan Yabancı Yatırımı ve Ekonomik Büyüme İlişkisi

The role of the energy sector in the economic growth and development of countries is not questionable. Thus, this sector process and structure are very important. The renewable energy resources are energies obtained from the continuous energies occurring naturally. In the Central Asian countries, the hydro electrical energy is one of the renewable energy resources, and it should be utilized by these countries to improve this sector. Energy consumption is one of socialeconomic development indicators. There are so many literatures about the relationship between energy consumption and economic growth. Unlike previous literatures, in this study FDI has been added as a third variable. In this study, whether or not FDI increases the economic growth and then economic growth increases energy consumption, will be analyzed by using time series methods analysis. Moreover, these relationships will be analyzed in five Central Asian (Kazakhstan, Kyrgyzstan, Tajikistan, Turkmenistan and Uzbekistan) countries during period 1991 to 2014. In this study, stationarity of series is formed and Johansen Cointegration test is utilized to see whether or not series are moving together in the long term.

Calibrated Configurations for Frenkel–Kontorova Type Models in Almost Periodic Environments

The Frenkel–Kontorova model describes how an infinite chain of atoms minimizes the total energy of the system when the energy takes into account the interaction of nearest neighbors as well as the interaction with an exterior environment. An almost periodic environment leads to consider a family of interaction energies which is stationary with respect to a minimal topological dynamical system. We focus, in this context, on the existence of calibrated configurations (a notion stronger than the standard minimizing condition). In any dimension and for any continuous superlinear interaction energies, we exhibit a set, called projected Mather set, formed of environments that admit calibrated configurations. In the one-dimensional setting, we then give sufficient conditions on the family of interaction energies that guarantee the existence of calibrated configurations for every environment. The main mathematical tools for this study are developed in the frameworks of discrete weak KAM theory, Aubry–Mather theory and spaces of Delone sets.

Double unification of particles with fields and electricity with gravity in non-empty space of continuous complex energies

Non-empty space reading of Maxwell equations as local energy identities explains why a Coulomb field is carried rigidly by electrons in experiments. The analytical solution of the Poisson equation defines the sharp radial shape of charged elementary densities which are proportional to continuous densities of electric self-energy. Both Coulomb field and radial charge densities are free from energy divergences. Non-empty space of electrically charged mass-energy can be described by complex analytical densities resulting in real values for volume mass integrals and in imaginary values for volume charge integrals. Imaginary electric charges in the Newton gravitational law comply with real Coulomb forces. Unification of forces through complex charges rids them of radiation self-acceleration. Strong gravitational fields repeal probe bodies that might explainthe accelerated expansion of the dense Metagalaxy. Outward and inward spherical waves form the standing wave process within the radial carrier of complex energy.

Translation of Ludwig Boltzmann’s Paper “On the Relationship between the Second Fundamental Theorem of the Mechanical Theory of Heat and Probability Calculations Regarding the Conditions for Thermal Equilibrium” Sitzungberichte der Kaiserlichen Akademie der Wissenschaften. Mathematisch-Naturwissen Classe. Abt. II, LXXVI 1877, pp 373-435 (Wien. Ber. 1877, 76:373-435). Reprinted in Wiss. Abhandlungen, Vol. II, reprint 42, p. 164-223, Barth, Leipzig, 1909

Translation of the seminal 1877 paper by Ludwig Boltzmann which for the first time established the probabilistic basis of entropy. Includes a scientific commentary.

Study of the high-lying, high-spin α + 28Si resonance structure in 32S

The structure of highly excited elastic α-scattering resonances in 32S was studied with the reaction 28Si(α, α0)28Si at beam energies between 22 and 30 MeV. The data were collected with a thick-target method giving continuous energies. The properties of 24 resonances in the spin range ℓ = 9–12ℏ, and up to 32 MeV excitation in 32S, were determined. The strong drop-off in elastic cross section at about 27.5 MeV laboratory energy was studied, and a similar but less drastic effect is observed at 21.5 MeV. Some possible explanation for these behaviours is discussed. The present results complement previous high-resolution data at lower energies, and favour the interpretation of the resonances as α-cluster states. The implications on potential models from resonances with angular momenta as high as 12ℏ are discussed.

Models of defects in atomistic systems

We analyze the overall behavior of discrete systems in the presence of defects (modeled by truncated quadratic potentials for some of the interactions) by exhibiting approximate free-discontinuity continuous energies. We give bounds on the limit surface energy densities, and we prove that these bounds are sharp in the classes of energy densities depending only on the normal to the discontinuity set, or concave and depending only on the jump across the interface. As a preliminary result we give a continuous descriptions of the ‘discrete Neumann sieve’.

Features of an intermetallic n-ZrNiSn semiconductor heavily doped with atoms of rare-earth metals

The crystal structure, density of electron states, electron transport, and magnetic characteristics of an intermetallic n-ZrNiSn semiconductor heavily doped with atoms of rare-earth metals (R) have been studied in the ranges of temperatures 1.5–400 K, concentrations of rare-earth metal 9.5 × 1019–9.5 × 1021 cm−3, and magnetic fields H ≤ 15 T. The regions of existence of Zr1 − xRxNiSn solid solutions are determined, criteria for solubility of atoms of rare-earth metals in ZrNiSn and for the insulator-metal transition are formulated, and the nature of “a priori doping” of ZrNiSn is determined as a result of redistribution of Zr and Ni atoms at the crystallographic sites of Zr. Correlation between the concentration of the R impurity, the amplitude of modulation of the bands of continuous energies, and the degree of occupation of potential wells of small-scale fluctuations with charge carriers is established. The results are discussed in the context of the Shklovskii-Efros model of a heavily doped and compensated semiconductor.

Features of electrical conductivity in the n-ZrNiSn intermetallic semiconductor heavily doped with the In acceptor impurity

The temperature and concentration dependences of resistivity and thermopower in a heavily doped and highly compensated semiconductor alloy ZrNiSn1−xInx in the temperature range T = 80–380 K at x = 0.005–0.15 are studied. It is assumed that the ZrNiSn semiconductor doped heavily with the In acceptor impurity is an amorphous semiconductor. It is experimentally established that there is a proportionality between the parameters of fluctuations in the bands of continuous energies, depth of fluctuations, and the depth of the potential well for a small-scale fluctuation. The conclusion advanced by Shklovskiĭ and Efros in 1972 [10] is experimentally confirmed for the first time; this conclusion is concerned with the assertion that, in a highly doped and completely compensated semiconductor, the maximum amplitude of fluctuations in the bands of continuous energies is equal to the half width of the band gap of the semiconductor, while the Fermi level is located near the midgap.

Conditions for attaining the maximum values of thermoelectric power in intermetallic semiconductors of the MgAgAs structural type

A condition for attaining the maximum values of thermoelectric power Z* in intermetallic semiconductors of the MgAgAs structural type consists in heavy doping of these semiconductors with donor and/or acceptor impurities with concentrations at which the Fermi level is pinned at the mobility threshold for the corresponding band of continuous energies. The maximum of the thermoelectric power is thermally stable under the condition that the impurity type and the type of the impurity band that give rise to the maximum in Z* are the same.

A theoretical, continuous alternative to the discrete electrode array

We present the theoretical use of a waveguide as an alternative to the electrode array in cochlear implants (CIs). Using continuous wave energies, the waveguide model allows for the construction of stimulation patterns at any given location within the auditory nerve. To illustrate this concept, we chose seven spectral peaks from the phoneme /i/ and used locations derived through a quasi-tonotopic relationship as stimulation targets. Simulations of the field generated by the waveguide indicate stimulation areas created at the target locations. We used a Hodgkin–Huxley nerve model to confirm that nerve activation only occurred at the desired locations.

Planck, the Quantum, and the Historians

In late 1900, the German theoretical physicist Max Planck derived an expression for the spectrum of black-body radiation. That derivation was the first step in the introduction of quantum concepts into physics. But how did Planck think about his result in the early years of the twentieth century? Did he assume that his derivation was consistent with the continuous energies inherent in Maxwellian electrodynamics and Newtonian mechanics? Or did he see the beginnings, however tentative and uncertain, of the quantum revolution to come? Historians of physics have debated this question for over twenty years. In this article, I review that debate and, at the same time, present Planck's achievement in its historical context.

X-ray polarization detector (abstract)

We designed and constructed a cylindrical gas proportional counter that can be used to analyze the linear polarization of x rays with a wide range of energy from 2 keV to 10 keV. The polarization sensitivity is based on the highly nonisotropic scattering of polarized x rays from a gas or solid target. The gas proportional counter surrounds the scattering chamber and measures the scattered x rays as a function of the azimuthal angle. The angle of scattered x rays is determined by the charge division of the anode resistive wire. This polarimeter without any moving parts can measure x rays with continuous energies. It is specially suitable for synchrotron x rays. We discuss the testing and performance of such an x-ray polarimeter.