Physics Perspective Research Articles

Implementing Environmental Education in the <i>Curricular Strategy</i> at Tertiary Education from the Perspective of Mathematics

Environmental education has become a vital topic in schools nowadays. From primary school to tertiary education, environmental education can be taught in every subject because of its versatility. However, in some universities this is not the case and some students ignore how their majors can contribute to raise their environmental education. The present work is directed to improve the performance of the students at the university level by designing and implementing teaching tasks to raise both their culture and their environmental education from the perspective of Mathematics. Some methods were applied in order to analyze the current design of the <i>Curricular Strategy</i> used in tertiary education and to determine how environmental education should be implemented in the <i>Curricular Strategy</i> without affecting its structure. Problems of differential equations from the discipline of Higher Mathematics were used as an alternative supported by a psycho-pedagogical approach. The exercises achieved the purpose stablished by the authors. Teaching tasks based on everyday life allow the students to understand the essence and get a more global vision of the object of study. This research was considered as a valid contribution for the confection of new curricular strategies and it also served as a basis to inspire some other works from the perspective of Physics and Biology.

Mechanism behind Time Dependent Elasticity of Crumb Rubber-Nano-Asphalt Hybrids Using Discrete Relaxation Spectrum

Crumb rubber powder is a successfully used renewable material obtained from waste tire rubber, which has been incorporated into paving asphalt since the 1930s due to its good resistance to deformation and fatigue as well as its eco-friendly performance. In this study, carbon nanotubes and nano silica were incorporated into the terminal blend crumb rubber modified asphalt technology to remedy the issues of excessive desulfurization and degradation of ground tyre rubber with this technology. The mechanism behind the high temperature delayed elastic properties of the crumb rubber-nano-asphalt hybrids was experimentally investigated based on discrete relaxation spectrum. Development of the discrete relaxation spectra was accomplished by fitting on the 60°C storage modulus data tested by the dynamic shear rheometer using the generalized Maxwell model. Subsequently, the feasibility of characterizing delayed asphalt elasticity using main relaxation time was verified by test results from the 60°C creep and recovery test. Results indicated that the crumb rubber-nano-asphalt hybrids exhibited arrheodictic behavior and the asphalt elasticity was strengthened by two nano agents. Moreover, the elasticity reinforcement with carbon nanotubes was greater than with nano silica. Additionally, a good correlation was observed between the 60°C zero shear viscosity and main relaxation time, and greater 60°C zero shear viscosity was correlated to longer main relaxation times. Furthermore, longer main relaxation time of the asphalt was related to greater average recovery rate in the creep and recovery test. This research is expected to shed some light on the mechanism behind time-dependent elasticity of crumb rubber modified asphalt from the perspective of polymer physics.

Editorial —EPL, a Physics Letters and Perspectives journal serving the community

Editorial —EPL, a Physics Letters and Perspectives journal serving the community

Status and Perspectives of the CBM experiment at FAIR

The CBM experiment, a fixed target experiment, designed to explore the QCD matter phase diagram in the baryon rich domain, is currently being constructed at the FAIR facility at GSI. The status of the construction towards the startup configuration of CBM and the initial physics goals are described. An outlook to the future physics perspectives is given.

Thorium ion exchange separation from rare earth elements ore samples following a combined attrition and dissolution procedure

Autogenous grinding (without grinding media) may provide some advantages if satisfactory lixiviation efficiency can be achieved on larger grain sizes. This grinding strategy requires less energy and offers important cost savings and reduction of GHG emissions in the mining industry compared to other commonly used approaches. Two attrition cells (1.2 L, 12 L) were designed to conduct a wet autogenous grinding. The combined grinding and leaching experiments were performed using six Canadian rare earth elements (REEs) ore samples to solubilize the REEs while grinding the ore in a modified attrition mill. Sulfuric, hydrochloric and nitric acids were compared under various operating conditions on three different types of ore samples (carbonatite, sedimentary, peralkaline). The addition of an alkaline step was also investigated. Metals dissolution in the 1.2 L attrition mill with or without NaOH addition (T = 20 °C, solid/liquid ratio = 20%, acid concentration [HNO3] = 7.5 M, time = 1 h) was found effective for the carbonatite ore (solubilization efficiencies of 91–99% Th, 29–32% U, 85–91% LREEs, 84–94% HREEs) and the sedimentary ore (solubilization efficiencies of 89–99% Th, 98–99% U, 22–83% LREEs, 48–99% HREEs). Actinide elements often comprise a significant component in REEs ore samples and are considered impurities. Their presence in primary REE mineral resources is problematic from a regulatory and health physics perspective. To overcome these issues, anionic, cationic and chelating resins were tested to remove Th from the nitric leaching liquor. Best separation results were obtained with the impregnated resin Lewatit VPOC 1026. To the best of our knowledge, this is the first time that Lewatit VPOC 1026 was reported in the literature for Th separation from REEs.

Study on the maximum value of flight distance based on the fractional differential equation for calculating the best path of shot put

Abstract From the perspective of physics, this article analyzes the various factors that affect the distance of shot put in the process of actual shot put. Based on the actual situation, it uses fractional calculus and physical formulas to calculate the shot throw distance and to conduct a comprehensive analysis. The experiment confirms that the three factors that affect the shot flying distance are the shot angle, shot speed, and shot height and analyzes the relationship between these three factors and the impact of each univariate on the shot flying distance. The analysis results show that among the three factors, the shot speed has the greatest impact on the flight distance, followed by the shot angle, and the shot height has the least effect; moreover, the optimal shot angle is not a specific value but a general range.

Coherent elastic neutrino-nucleus scattering ( CEνNS ) event rates for Ge, Zn, and Si detector materials

Realistic nuclear structure calculations are presented for the event rates due to coherent elastic neutrino-nucleus scattering (CE$\nu$NS), assuming neutrinos from pion-decay at-rest, from nuclear reactors and from Earth's interior. We focus on the currently interesting Germanium isotopes, $^{70,73,76}$Ge, which constitute detector materials of the recently planned CE$\nu$NS experiments. We study in addition the potential use of $^{64,70}$Zn and $^{28}$Si isotopes as promising CE$\nu$NS detectors. From nuclear physics perspectives, recently, calculations have been carried out within the framework of the deformed shell-model (DSM), based on realistic nuclear forces, and assessed on the reproducibility of spectroscopic nuclear properties. The high confidence level acquired by their agreement with experimental results and by their comparison with other mostly phenomenological calculations encouraged the use of DSM to extract predictions for the CE$\nu$NS event rates of the above isotopes. Our detailed estimation of the nuclear physics aspects of the recently observed neutral current coherent neutrino-nucleus scattering may shed light on unravelling the still remaining uncertainties for the CE$\nu$NS process within and beyond the Standard Model.

Resource Letter BP-1: Biological physics

This Resource Letter provides an overview of the literature in biological physics, a vast, active, and expanding field that links the phenomena of the living world to the tools and perspectives of physics. While no survey of this area could be complete, this list and commentary are intended to help provide an entry point for upper-level undergraduates, graduate students, researchers new to biophysics, or workers in subfields of biophysics who wish to expand their horizons. Topics covered include subcellular structure and function, cell-scale mechanics and organization, collective behaviors and embryogenesis, genetic networks, and ecological dynamics.

Technical Challenges to the Delivery of Quality Radiation Therapy During the COVID-19 Unlock Period: Medical Physics Perspective

The Covid-19 onset was very pandemic for all of society all over the world. To overcome this state of affairs, the country’s government had done the lockdown in their respective countries. The lockdown helped the people from spreading the Covid-19 virus among people, however, it affected another part of life such as people becoming unemployed. The health care sector was affected a lot by the lockdown as the patient faced lots of problems such as reaching the hospital, meeting the concerned staff, getting the treatment on time, etc. Covid-19 affected the cancer patients most, during the lockdown. After awareness of Covid-19, when the world has started towards the unlock down. With the little negligence of people, the world has started facing the peak of Covid-19. And, there was more crowd in the health care sectors, therefore the hospital staff got infected a lot, as the patient treatment cannot be carried out from home. Cancer patient treatment, which comes under radiotherapy, has already existed in chronic medical conditions, such as lung cancer patients, esophagus cancer patients, heart disease patients, etc, has a higher risk of Covid-19 infection. During treatment, when such a patient comes in contact with a radiation oncologist, medical physicist, and radiation technologist, then some of the staff get infected through patients. To prevent such spread, all the medical staff should strictly follow the rules made for staff. In this article, we are sharing the challenges for the medical physics team and some suggestions during patient care.

MODEL OF MECHANISM OF CONVERSION OF EXTERNAL ACTION INTO NATURAL OSCILLATIONS

The work presents a geometrical interpretation of a mathematical model intended to give a specific description of the process of conversion of external dynamic action into natural oscillations of a part. Besides geometrical constructions, the essence of the model stems from the strict logic as well, following which the model does not have a tangible embodiment. Nonetheless, it is a function space, in which the process is being generated and energy of natural oscillations is getting accumulated, i.e. the model is an non-material carrier of free energy of elastic oscillations. Material carrier is the very part. The model is represented as the Riemannian space, in which all dynamic parameters are constant and set to zero, therefore, on the one side, it appears as if it does not have any tangible embodiment. On the other side, by nature, the model is a necessary expansion of the function space, which, on the qualitative level, allows to obtain explanation of a number of processes, which are observed experimentally, but to this day were not provided with a specific substantiation from a physics perspective. The proposed model can be an effective tool for analysis of processes, occurring in the course of non-destructive testing and vibration-based diagnostics. For example, the Article presents a theoretical justification of the process of modelling of cracks in the non-destructive testing methods, using natural oscillations of the item being checked. On top of that, it gives a derivation of the formula determining amount of the crack detected through these methods.

Exceptional points of all-dielectric nanoresonators

In the recent years, all-dielectric nanophotonics has been showing promising potential for biotechnology, with important progress in the development of efficient all-optical, all-dielectric nanosensing devices overcoming the ohmic losses inherently present in their plasmonic counterparts. In the quest to achieve single molecule sensitivities, a judicious design of the optical response of the nanoantennas is required. Here, we approach this problem from the perspective of non-Hermitian physics and investigate the interaction of two finite nanorods supporting Mie resonances, with the aim of maximizing the frequency detuning induced by a perturbation of the structure. We develop a simple semi-analytical technique to efficiently investigate the coupled system, and we find that Coulomb interactions, together with mutual interference induced by breaking the dimer symmetry, can effectively bring the structure towards a non-Hermitian singularity, an exceptional point, that can potentially increase the sensitivity. The results of this work are expected to lead to novel developments in all-optical single molecule detection, and merge for the first time all-dielectric nanophotonics with exceptional point physics.

A laboratory investigation of electrical influence on the freezing of water drops: A cloud physics perspective

A laboratory investigation of electrical influence on the freezing of water drops: A cloud physics perspective

Recent Progress and Perspectives of Field‐Effect Transistors Based on p‐Type Oxide Semiconductors

Oxide semiconductors are considered as one of the most promising candidates for back‐end‐of‐line transistors for monolithic 3D integration due to various advantages, such as complementary metal–oxide–semiconductor (CMOS)‐compatible method, low fabrication temperature, and promising electrical characteristics. As such, the demand for p‐type oxide semiconductors that are comparable to their n‐type oxide counterparts is increasing. However, the inferior electrical characteristics of p‐channel field‐effect transistors based on oxide semiconductors hinder their widespread application. Thus, the development of high‐performance p‐type oxide semiconductors is essential for their implementation in next‐generation electronics, which have requirements such as innovative form factors, high power efficiencies, and superior transparency. Herein, strategies for improving the device performances of p‐type oxide semiconductors fabricated via CMOS‐compatible methods are reviewed from a material science and device physics perspective, and a brief history of p‐type oxide semiconductors is discussed. Furthermore, critical issues for p‐type oxide semiconductors, such as the transport mechanism, bias stress stability, high off‐current, and ambipolar behavior, are discussed.

Ultrasonically Propelled Micro‐ and Nanorobots

AbstractUltrasound at sufficiently low amplitudes, specifically in the MHz frequency range, does little harm to the biological samples (such as cells and tissues) and provides an advantageous and well‐controlled means to efficiently power microswimmers. In this review, a state‐of‐the‐art overview of ultrasonically propelled micro‐ and nanorobots from the perspective of chemistry, physics, and materials science is given. First, the well‐established theory of ultrasound propulsion for micro/nanorobots is introduced. Second, the setup designs for ultrasound propulsion of micro/nanorobots are classified. Following this, the presentative fabrication methods of ultrasonic micro/nanorobots are summarized in detail. After this, the mechanisms of ultrasound propulsion for micro/nanorobots are explored and discussed. The hybrid motion of magnetic‐, light‐, and catalytic‐driven micro/nanorobots with ultrasonic actuation is then summarized and discussed. Subsequently, this review highlights and discusses representative potential applications of ultrasound‐powered functional micro/nanorobots in biomedical, environmental, and other relevant fields. Lastly, this review presents a future outlook on the ultrasound‐driven micro/nanorobots.

Non-Hermitian bath model for arrays of coupled nanoresonators

Nanophotonics systems have recently been studied under the perspective of non-Hermitian physics. Given their potential for wavefront control, nonlinear optics and quantum optics, it is crucial to develop predictive tools to assist their design. We present here a simple model relying on the coupling to an effective bath consisting of a continuum of modes to describe systems of coupled resonators, and test it on dielectric nanocylinder chains accessible to experiments. The effective coupling constants, which depend non-trivially on the distance between resonators, are extracted from numerical simulations in the case of just two coupled elements. The model predicts successfully the dispersive and reactive nature of modes for configurations with multiple resonators, as validated by numerical solutions. It can be applied to larger systems, which are hardly solvable with finite-element approaches.

Symmetries and Geometries of Qubits, and Their Uses

The symmetry SU(2) and its geometric Bloch Sphere rendering have been successfully applied to the study of a single qubit (spin-1/2); however, the extension of such symmetries and geometries to multiple qubits—even just two—has been investigated far less, despite the centrality of such systems for quantum information processes. In the last two decades, two different approaches, with independent starting points and motivations, have been combined for this purpose. One approach has been to develop the unitary time evolution of two or more qubits in order to study quantum correlations; by exploiting the relevant Lie algebras and, especially, sub-algebras of the Hamiltonians involved, researchers have arrived at connections to finite projective geometries and combinatorial designs. Independently, geometers, by studying projective ring lines and associated finite geometries, have come to parallel conclusions. This review brings together the Lie-algebraic/group-representation perspective of quantum physics and the geometric–algebraic one, as well as their connections to complex quaternions. Altogether, this may be seen as further development of Felix Klein’s Erlangen Program for symmetries and geometries. In particular, the fifteen generators of the continuous SU(4) Lie group for two qubits can be placed in one-to-one correspondence with finite projective geometries, combinatorial Steiner designs, and finite quaternionic groups. The very different perspectives that we consider may provide further insight into quantum information problems. Extensions are considered for multiple qubits, as well as higher-spin or higher-dimensional qudits.

A Hypothesis about the Physical Nature of the Phenomenon of Life (A Contribution to the Discussion of the Paper by G.R. Ivanitskii 21st Century: What Is Life from the Perspective of Physics)

A macroscopic quantum state that is characterized by an energy gap in the electronic spectrum and occurs in organic structural components of the cell is hypothesized to provide a basis for the phenomenon of life. The width of the band gap has been estimated. The possibility of detecting this energy gap in an experimental study is discussed.

The Dilemma of Balancing Design for Impact Sound with Environmental Performance in Wood Ceiling Systems—A Building Physics Perspective

Due to the high consumption of resources and energy in the construction sector, the development of resource-efficient and sustainable construction solutions is gaining increasing attention. The awareness of sustainability and resource conservation results in the interest of using natural and renewable materials in contemporary architecture. Timber construction methods offer both constructive and ecological potential for sustainable solutions. From a building physics perspective, the acoustic performance of lightweight buildings, such as those made of timber, presents a challenge. Even if standard requirements are met, the increased low-frequency sound transmission typical for light-weight construction can cause discomfort and is already the subject of questions in building physics, which are currently increasingly extending to timber construction. Within the framework of a holistic approach, this paper compares the problem of acoustic properties, design optimizations and the ecological properties of timber-frame and solid timber construction components. The comparison with heavy materials, such as concrete, shows the relation of acoustic optimization with the change of the environmental profile. In order to establish the interaction between acoustic quality of wooden ceiling constructions and their ecological characteristics, this article aims to demonstrate the potential of materials used in the building sector under ecological aspects considering a life cycle analysis.

Examining normal modes as fundamental heat carriers in amorphous solids: The case of amorphous silicon

Normal mode decomposition of atomic vibrations has been used to provide microscopic understanding of thermal transport in amorphous solids for decades. In normal mode methods, it is naturally assumed that atoms vibrate around their equilibrium positions, and that individual normal modes are the fundamental vibrational excitations transporting heat. With the abundance of predictions from normal mode methods and experimental measurements now available, we carefully analyze these calculations in amorphous silicon, a model amorphous solid. We find a number of discrepancies, suggesting that treating individual normal modes as fundamental heat carriers may not be accurate in amorphous solids. Furthermore, our classical and ab initio molecular dynamics simulations of amorphous silicon demonstrate a large degree of atomic diffusion, especially at high temperatures, leading to the conclusion that thermal transport in amorphous solids could be better described starting from the perspectives of liquid physics rather than from crystalline solids.

Poisson–Lie Groups and Gauge Theory

We review Poisson–Lie groups and their applications in gauge theory and integrable systems from a mathematical physics perspective. We also comment on recent results and developments and their applications. In particular, we discuss the role of quasitriangular Poisson–Lie groups and dynamical r-matrices in the description of moduli spaces of flat connections and the Chern–Simons gauge theory.