Movement and Diffusion of the Helium Atom in Nanostructures (in Pores) with Water

The influence of water-filled nanoscale defects on the total movement of helium atoms through a quartz crystal is considered. The approximation of local chains is used, the interaction constant of which characterizes the interaction of the helium atom with the environment. The appearance of water molecules in defects (pores) leads to the renormalization of this interaction. The D'Alembert principle is used to evaluate this renormalization. The effect of such a renormalization of the interaction on the diffusion coefficient of helium through a crystal with defects filled with water is considered.

Bosonic Hofstadter butterflies in the presence of phonon modes

We have investigated the influence of lattice sites vibrations on bosonic Hofstadter’s butterfly (HB) spectrum for the case of conventional square lattice. Only the pair of specific phonon modes with opposite quasimomenta has been taken into account. The study has shown that HB-type spectra can be substantially modified by the presence of phonons, depending on the ratios of such parameters of the system as site-to-site transition amplitudes, particle-phonon interaction constant, and characteristic vibration frequency.

Remarkable Properties of Isotope Effect

Present paper is devoted to the non - accelerator manifestation of the strong nuclear interaction - the heart of quantum chromodynamics (QCD) which is part of the Standard Model (SM). The observation of isotopic shift (0.103 eV) of the zero - phonon emission line in photoluminescence spectra of LiD crystals (possessing a strict interaction in the deuterium nucleus) comparison with LiH (in the hydrogen nucleus of which there is no strong interaction) is a first direct proof of the strong nuclear long - range character. The non - accelerating measurement of the strong interaction constant from the distance between nucleons made it possible to find the maximum possible value of αs = 2.4680. The isotopic acquisition of mass by massless fermions is briefly discussed

A Panax notoginseng Root Tip Meristem Biosensor and Its Sensing Kinetics for Five Important Nitrogen Nutrients

Plants absorb nitrogen mainly through their roots. Nitrogen sensing is required for the absorption and transport of different nitrogen nutrients. In this study, we constructed biosensors with immobilized Panax notoginseng root tip meristems based on a three-electrode system and successfully determined the kinetics of the interactions between the P. notoginseng root tip meristems and five important nitrogen nutrients, namely, urea, sodium nitrate, sodium glutamate, disodium inosinate, and disodium guanylate. We discovered that the biosensor’s sensing kinetics was similar to the enzyme–substrate kinetics, and the receptor–ligand interconnected allosteric interaction constant Ka (mol/L), analogous to the Michaelis constant, was calculated. The result showed that the root tip meristems of two- to four-year-old P. notoginseng plants had a higher capacity to sense inorganic nitrogen nutrients (sodium nitrate and urea) than the three organic nitrogen nutrients. The ability of the plants to sense inorganic nitrogen nutrients decreased with an increase in plant age. The sensing sensitivity of four-year-old P. notoginseng plants to disodium inosinate and disodium guanylate was 100- to 10,000-fold lower than that of the two- and three-year-old plants. Additionally, the capability to sense sodium glutamate decreased initially and then increased with an increase in plant age. The biosensors reached an ultra-sensitive level ( 1 × 10 − 22 mol/L) in sensing the five nitrogen nutrients and exhibited advantages such as good stability and reproducibility, low cost, a simple structure, and a rapid response, providing a new approach for quantitative determination of the capability of plants to sense different nitrogen nutrients.

QUANTUM SIZE EFFECT IN SUPERCONDUCTORS

In the middle of the last century, it was demonstrated that with a decrease in the size of superconducting structures, for example, the thickness of a thin film, its critical temperature TC shifts by a certain amount. It increases in aluminum, tin, and indium, and decreases in mercury, niobium, and lead. However, there is still no generally accepted theory explaining this effect. In the 1970s, during the largest volume of research on this topic, V.L. Ginzburg assumed that the transition temperature of a sufficiently pure, monocrystalline superconductor film will be exactly the same as in a bulk body. However, this assumption has not yet been verified, and the question about the nature of this effect still remains open. For the study, we chose aluminum, due to the fact that the dependence of TC of the film on its thickness is very predictable and increases with decreasing size. Despite a number of works on studying this dependence in aluminum, it is not always possible to accurately establish a correspondence with a theory. This is because characteristics vary from sample to sample, even made in the same batch. In our case, polycrystalline films were prepared, the crystallite sizes in which are comparable to the film thickness, and epitaxial samples with an atomically smooth surface. The films were fabricated using electron-beam deposition and molecular-beam epitaxy on various substrates. Within the BCS model, the critical temperature of the superconducting transition exponentially depends on the density of electronic states at the Fermi level N ( EF ) and the electron-phonon interaction constant V : TC ~ exp(-1/[ N ( EF )* V ]). It is shown in this work that, due to QSE in thin superconducting films, both parameters N ( EF ) and V change nonmonotonically with the sample thickness. This behaviour is a consequence of the form resonance theory. Presumably, the effect caused by disordering of crystallites, as well as by the surface or substrate, does not play a dominant role specifically in our case, since the aluminum films are of high quality, and their thicknesses go far beyond the limits of ultrathin objects, in which surface phenomena become of decisive importance. As a result of this study, the experimental and theoretical dependences of TC on the thickness of films prepared by different methods on different substrates were obtained.

THz-излучение в магнитном переходе Fe/Mo

An investigation was made of THz radiation in the Fe/Mo magnetic junction arising from the pumping by a high-density current of the upper spin subband in the induced ferromagnetism layer in Mo. The tensor character of the exchange interaction constant at the Fe / Mo interface, associated with the presence of the Dzyaloshinsky-Moriya interaction, promotes radiative relaxation.

Криоспектроскопическое исследование резонансных мультиплетов ν-=SUB=-s-=/SUB=- ~2ν-=SUB=-b-=/SUB=- в молекуле CHF-=SUB=-3-=/SUB=-

The sequences of Fermi resonances vs~2vb in the IR spectrum of a solution of fluoroform (CHF3) in liquefied krypton are investigated. Here vs is the CH stretching vibration, vb is the bending vibration. It is shown that for a correct description of resonance multiplets (polyads) at a high degree of vibrational excitation, it is necessary to use an extended set of spectroscopic parameters. In particular, it is necessary to take into account the dependence of the anharmonic interaction constant asbb on the vibrational quantum numbers. The conclusions are generalized for the arbitrary case of the CH-chromophore CHX3.

Fidelity of noisy multiple-control reversible gates

The effect of frequency noise on correct operation of the multiple-control Toffoli, Fredkin, and Peres gates has been discussed. In the framework of the Ising model, the energy spectrum of a chain of atoms with nuclear spins one-half in a spinless semiconductor matrix has been obtained, and allowed transitions corresponding to the operation algorithm of these gates have been determined. The fidelities of the obtained transitions were studied depending on the number of control qubits and parameters of the radio-frequency control pulses. It has been shown that correct operation of the Toffoli and Fredkin gates does not depend on the number of control qubits, while the Peres gate fidelity decreases significantly with the increasing number of control signals. The calculated ratios of the Larmor frequency to the exchange interaction constant correspond with the results of other studies.