Asymptotic and numerical analysis of slowly varying two-dimensional quantum waveguides

The work is devoted to the asymptotic and numerical analysis of the wave function propagating in two-dimensional quantum waveguides with confining potentials supported on slowly varying tubes. The leading term of the asymptotics of the wave function is determined by an adiabatic approach and the WKB approximation. Unlike other similar studies, in the present work we consider arbitrary bounded potentials and obtain exact solutions for the thresholds, and for the transverse modes in the form of power series of the spectral parameter. Our approach leads to an effective numerical method for the analysis of such quantum waveguides and for the tunnel effect observed in sections of the waveguide that shrink or widen too much. Several examples of interest show the applicability of the method.

Prediction of Conductive Anomalies Ahead of the Tunnel by the 3D-Resitivity Forward Modeling in the Whole Space

Water inrush in tunneling poses serious harm to safe construction, causing economic losses and casualties. The prediction of water hazards before tunnel excavations becomes an urgent task for governments or enterprises to ensure security. The three-dimensional (3D) direct current (DC) resistivity method is widely used in the forward-probing of tunnels because of its low cost and highly sensitive response to water-bearing structures. However, the different sizes of the tunnel will distort the distribution of the potential field, which causes an inaccurate prediction of water-bearing structures in front of the tunnels. Some studies have pointed out that the tunnel effect must be considered in the quantitative interpretation of the data. However, there is rarely a predicted model considering the tunnel effect to be reported in geophysical literature. We developed a predicted model algorithm by considering the tunnel effect for forward-probing in tunnels. The algorithm is proven to be feasible using a slab analytic model. By simulating a large number of models with different tunnel sizes, we propose an equation, which considers the tunnel effect and can predict the water-bearing structures ahead of the tunnel face. The Monte Carlo method is used to evaluate the quality of the predicted model by simulating and comparing 10,000 random models. The results show that the proposed method is accurate to forecast the water-rich structures with small errors.

About the fire hazard of transport hydrotunnels

В статье рассмотрена достаточно новая проблема, связанная с появлением и развитием перспективной транспортной инфраструктуры – гидротоннелей. Показано, что ввиду большой пожарной нагрузки, которую представляют собой проходящие по гидротоннелю суда (пассажирские, сухогрузы, контейнеровозы. танкеры) возможно возникновение пожаров, угрожающих как самим судам и их экипажам, так и конструкции гидротоннеля – обрушение его свода из-за экстремальных тепловых нагрузок. Проведено компьютерное моделирование с использованием полевой модели пожара, подтвердившее факт быстрого роста температуры и концентрации токсичных продуктов горения, а также «тоннельный эффект» - прохождение высокотемпературного потока газов к одному из торцов тоннеля. Даны предложения по действиям персонала судов в гидротоннеле и пожарных кораблей по тушению пожара и спасению людей. Показана необходимость оборудования некоторых гидротоннелей дренчерными системами пожаротушения. Сделан вывод о необходимости дальнейших исследований в части пожарной безопасности транспортных гидротоннелей и разработке соответствующего нормативного документа. The article considers a fairly new problem associated with the emergence and development of a promising transport infrastructure – hydrotunnels. It is shown that due to the large fire load, which is represented by vessels passing through the hydrotunnel (passenger, dry cargo, container ships. tankers) there may be fires that threaten both the ships themselves and their crews, and the structure of the hydrotunnel – the collapse of its arch due to extreme thermal loads. A computer simulation was carried out using a field model of a fire, which confirmed the fact of a rapid increase in temperature and concentration of toxic combustion products, as well as the "tunnel effect" - the passage of a high-temperature gas flow to one of the ends of the tunnel. Suggestions are given on the actions of the personnel of vessels in the hydrotunnel and fire ships to extinguish the fire and rescue people. The necessity of equipping some hydrotunnels with drencher fire extinguishing systems is shown. The conclusion is made about the need for further research in terms of fire safety of transport hydraulic tunnels and the development of an appropriate regulatory document.

Why Africans tolerate income inequality

African attitudes to income inequality have hardly been studied. As a result, we may have been missing a crucial part of the answer to the question why Africa is so unequal. This paper presents evidence that, across all self-identified class categories, African respondents in 16 African states, representative of all the regions of the continent, are on average considerably more tolerant of inequality than respondents from 43 comparable developing and transition countries. The aim of the paper is to try and explain these differences. It concludes that (a) a modified version of Albert Hirschman's notion of the ‘tunnel effect’ and (b) religious devotedness in the African context provide explanations for the observed variation between African respondents and their counterparts elsewhere. Experienced inequality, in contrast to overall income distribution, influences the tunnel effect more widely than economic growth. Religious belief shapes inequality tolerance in Africa more than the observance of religious practices.

Quamtum Mechanical Approach to Gas Phase Reaction of Isopropanol with Sulfanyl Radical

i-C3H7OH (IPA) is one of the potential fuel additives. The reaction mechanism of isopropanol with sulfanyl radical was investigated at the CCSD(T)//B3LYP/6-311+G(3df,2p) level of theory. Ten possible reaction pathways giving PR1-PR10 including three H-abstraction reactions and seven substitution reactions were considered. Based on the determined potential energy surface and molecular parameters, the rate constants and branching ratios of each reaction pathway were calculated at the temperature range of 298K - 2000K by using the transition state theory considering the Eckart tunnel effect. The kinetics results showed that at 298K, the reaction products were mainly PR2 ((CH3)2COH + H2S) (~ 100%). However, at 2000K, the contribution of PR2 decreased to 77.8% of the total product, while, PR3 (CH3CH(CH2)OH + H2S) and PR1 ((CH3)2CHO + H2S) accounted for 16.7% and 5.5% of the total product, respectively.

Rejection of Rutherford's Planetary Model of the Atom, Bohr's Postulates and the Tunnel Effect

The article raises the question of the strange behavior of electrons in an atom, when the electronic orbitals of the P- and d-states of the atom have the form of eights with nodal points in the nucleus of the atom, as well as the discovery of the mysterious K-capture of an electron when the nuclei of atoms of some isotopes of chemical elements someh they sometimes capture an electron from the inner (K- or L-) electron shell of the atom. It has not been possible to explain these phenomena within the framework of the atomic model existing in quantum electrodynamics. In the new model of the atom, proposed by Professor Lev Sapogin in Unitary Quantum Theory, the electron makes quantum leaps within the orbital not randomly, as physicists thought, but through the nucleus of the atom, each time tunneling through it. In this case, the quantization of the energy levels (orbitals) of electrons in an atom is explained by the distribution of nodes and antinodes in a standing wave of an electron, and an integer number of de Broglie wavelengths should be located in the diameter of the electron orbital. The article shows the dependence of the magnitude of the interaction constants in the hydrogen nucleus and, in particular, the fine structure constant, discovered by the CMS cooperation in experiments at the Large Hadron Collider in 2019, during reactions in pp collisions with energies from 1 TeV to 13 TeV and an intranuclear pressure of 10³⁵ Pascal. The value of the fine structure in the near-Earth medium and in a neutron star is given

A New Tunnel Effect? The Impact of Stress on Vote Choice

The literature shows a link between stress and voter turnout, but does stress influence vote choice as well? What would explain such a relationship? Using a survey of Quebec (Canada) voters conducted during the 2017 municipal election (n = 1,130), we show that 1) there is a relationship between stress and vote choice, and 2) voters who consider road congestion to be an important issue and who report being stressed tend to vote for the party that has taken a stand in favor of highway projects and against public transit. While many studies show an association between road congestion and the psychological health of individuals, our research invites us to consider the political impacts of such a relationship.

Leading role of the principles of interaction between the natural physical factors and integral organism in medicine of the future

The paper discusses the search of evidences of advantage of the physiotherapy over the drug therapy by the parameters and treatment methods according to clinical stage of a disease development, based on the results of labor medical examination and improvement of the quality of life. The above indicators were confirmed with a high statistical accuracy by example of a new rehabilitation technology: "Underwater horizontal spine traction with underwater phototherapy to solve an essential medical and social problem: treatment of patients with degenerative and dystrophic lesions of the lumbosacral spine with herniated protrusions of intervertebral discs, being one of the most common neurological pathologies worldwide. Based on the achievements in physics, i.e. discovery of "evanescent waves", "scanning tunneling microscope"; "AC and DC Josephson effects", development of highly sensitive equipment and discovery by the author of the present article of a highly informative, non-invasive, simple, harmless method of studying the mechanism of action of physical factors on the integral organism from any part of the skin surface, i.e. "blood spectrum biopsy" displaying the complete information picture of an organism, it became possible to create a new theory of a mechanism of action of physical factors on the supramolecular level of the integral organism on the principle of "tunnel effect".

Electron Transfer through a Natural Oxide Layer on Real Metal Surfaces Occurring during Sliding with Polytetrafluoroethylene: Dependence on Heat of Formation of Metal Oxides

Electron emission (EE) from real metal surfaces occurring during sliding contact with a polytetrafluoroethylene (PTFE) rider has been investigated using the thermodynamic data of metal oxides and the X-ray photoelectron spectroscopy (XPS) intensity ratio of oxygen/metal on the surfaces. EE was termed triboelectron emission (TriboEE). Rolled metal sheets of 18 types were used. The metal‒oxygen bond energy calculated from the heat of the formation of metal oxide, (D(M–O)), was shown to be a key factor in dividing the EE into two routes, the so-called Schottky effect and the tunnel effect, due to the surface oxide layer. The metals in periodic groups 4 (Ti and Zr), 5 (V, Nb, and Ta), and 6 (Mo and W) maintained higher values of D(M–O), while, moving down the groups, the TriboEE intensity increased, being ascribed to the former route. In groups 10 (Ni, Pd, and Pt) and 11 (Cu, Ag, and Au), the D(M–O) values decreased moving down the groups, but the TriboEE intensity increased significantly, which can be attributed to the latter route. Furthermore, with the increase in the electrical conductivity of metals, the TriboEE intensity became remarkably high, while the D(M–O) value fell rapidly and became almost constant. The XPS results showed that the dependence of the D(M–O) and XPS metal core intensity on the O1s intensity and the XPS intensity ratio of the O1s/metal core was different between groups 10 and 11 and groups 4, 5, and 6. It was concluded that, under the electric field caused on the real metal surface by the friction with PTFE, the electron from metals with small D(M–O) values predominantly tunnels the surface oxide layer as a surface barrier, while with large D(M–O) values, the electron passes over the top of the barrier.