Search

Postulating that academic papers can positively impact the actual teaching practices of science teachers, this study analysed the process of understanding and utilising academic papers by science teachers to teach scientific creativity in their schools. The 45--hour graduate course of three science teachers was explored to identify the difficulties teachers encountered in trying to understand academic papers and to discover how to solve these difficulties. Second, which aspects should be considered when developing teaching materials for scientific creativity to be used in schools were analysed. A transformation model of an academic paper was proposed to understand this process, and the results were organised accordingly. According to this model, it was emphasized to translate academic papers from a general and abstract state to a local and concrete state. Therefore, the role of science educators as knowledge translators was discussed for more practical and effective use of academic papers in school. This study is expected to contribute to research-based teaching by linking academic research with teaching practice.

To improve the accuracy and efficiency of the aging life prediction and assessment of transformer oil-paper insulation, and to make up for the deficiencies of traditional characterizers, such as 2-furfural, carbon monoxide, and carbon dioxide, a method for the simultaneous determination of methanol, ethanol, $n-\mathbf{propanol}$, and $n$-butanol in oil with a single injection is established by headspace-gas chromatography-mass spectrometry. The measured results show that the determination limits of the four alcohol characterizers can be controlled to $\mathbf{10}\ \mu \mathbf{g}/\mathbf{kg}$ level. Based on this method, the change patterns of the above four alcohols with thermal aging time and degree of polymerization are obtained through thermal aging experimental research. Ethanol, $n$-propanol, and $n$-butanol in oil indicate nearly linear correlations with thermal aging time and degree of polymerization, similar to that of methanol. By analyzing 52 sets of measured data of 500 kV EHV transformers in operation, $n$-butanol is found to have excellent performance, and a new method to evaluate the aging state of oil-paper insulation employing $n$-butanol and methanol is proposed along with the aging attention value model. The measured data of 500 kV EHV transformers in operation indicate that the combination of $n$-butanol and methanol as the preferred characterizers can effectively compensate for the shortcoming of traditional characterizers in the early stages of aging, and the feasibility of the method is verified. Two possible pathways for the generation of $n$-butanol by cellulose cleavage during the aging of oil-paper are proposed from the chemical structure of cellulose.

Abstract This study identifies important factors for designing an effective biomimetic paper‐based fog harvesting substrate by examining the harvesting properties of different surfaces, including glass, polyethylene, and superhydrophobic paper. In laboratory‐scale fogging tests, the wetting behavior of the substrates is characterized, and the importance of the tilt angle of the respective surface relative to the fog flow is elaborated. Because successful fog harvesting requires both efficient accumulation of water droplets on the surface (by condensation and collision) and sufficient but not excessive roll‐off of the liquid, the amount of water finally collected is clearly related to the pinning effect, which should prevent the smallest droplets from being carried away by the wind but must not lead to full and permanent wetting of the surface. Coalescence is identified as a major phenomenon to improve droplet roll‐off. In this context, superhydrophobic paper indicates to be a more effective water collector than glass or polyethylene, especially when oriented vertically, since it allows the droplets to roll off very efficiently. Finally, the addition of glass particles to the superhydrophobic coating is proposed as a means of enhancing pinning and improving the fog harvesting efficiency.

In this study we compare the titles of scientific letters and those of research papers published in the field of astrophysics in order to identify the possible differences and/or similarities between both genres in terms of several linguistic and extra-linguistic variables (length, lexical density, number of prepositions, number of compound groups, number of authors and number of countries mentioned in the paper bylines). We also carry out a cross-genre and cross-journal analysis of the referred six variables. Our main findings may be summarized as follows: (1) When compared to research paper titles, scientific letter titles are usually shorter, they have a lower lexical density, they include a higher number of prepositions per number of words and a lower number of compound groups per number of words, although they have more up to 4-word compound groups, i.e. the simplest ones. As a consequence, scientific letter titles include less information, which is also less condensed, than research paper titles. (2) The predominance of compound adjectives over compound nouns in the titles of both genres highlights the scientificity of astrophysical discourse. (3) In general terms, our data show a positive correlation between title length and the number of countries mentioned in the bylines for both genres. The positive correlation between title length and number of authors is only met in the case of research papers. In light of these findings, it may be concluded that scientific letters are a clear example of a timeliness and more "immediate" science, whereas research papers are connected to a more timeless and "elaborate" science. It may also be concluded that two different collaboration scenarios are intertwining on the basis of three separate geographic and linguistic publication contexts (Mainland Europe, The United Kingdom and The United States of North America).

Abstract Paper, an inexpensive material with natural biocompatibility, non‐toxicity, and biodegradability, allows for affordable and cost‐effective substrates for unconventional advanced electronics, often called papertronics. On the other hand, polymeric elastomers have shown to be an excellent success for substrates of soft bioelectronics, providing stretchability in skin wearable technology for continuous sensing applications. Although both materials hold their unique advantageous characteristics, merging both material properties into a single electronic substrate reimagines paper‐based bioelectronics for wearable and patchable applications in biosensing, energy generation and storage, soft actuators, and more. Here, a breathable, light‐weighted, biocompatible engineered stretchable paper is reported via coaxial nonwoven microfibers for unconventional bioelectronic substrates. The stretchable papers allow intimate bioconformability without adhesive through coaxial electrospinning of a cellulose acetate polymer (sheath) and a silicone elastomer (core). The fabricated cellulose‐silicone fibers exhibit a greater percent strain than commercially available paper while retaining hydrophilicity, biocompatibility, combustibility, disposable, and other natural characteristics of paper. Moreover, the nonwoven stretchable cellulose‐silicone fibrous mat can adapt conventional printing and fabrication process for paper‐based electronics, an essential aspect of advanced bioelectronic manufacturing.

Abstract We report an innovative and facile approach to fabricating an ultrasensitive plasmonic paper substrate for surface-enhanced Raman spectroscopy (SERS). The approach exploits the self-assembling capability of poly(styrene-b-2-vinyl pyridine) block copolymers to form a thin film at the air-liquid interface within the single microdroplet scale for the first time and the subsequent in situ growth of silver nanoparticles (AgNPs). The concentration of the block copolymer was found to play an essential role in stabilizing the droplets during the mass transfer phase and formation of silver nanoparticles, thus influencing the SERS signals. SEM analysis of the morphology of the plasmonic paper substrates revealed the formation of spherical AgNPs evenly distributed across the surface of the formed copolymer film with a size distribution of 47.5 nm. The resultant enhancement factor was calculated to be 1.2 × 107, and the detection limit of rhodamine 6G was as low as 48.9 pM. The nanohybridized plasmonic paper was successfully applied to detect two emerging pollutants—sildenafil and flibanserin—with LODs as low as 1.48 nM and 3.45 nM, respectively. Thus, this study offers new prospects for designing an affordable and readily available, yet highly sensitive, paper-based SERS substrate with the potential for development as a lab-on-a-chip device.

In this paper, the thermo-electric, phonon, electronic, and optical properties of the C3N monolayer have been investigated using the Wien2K computational code based on first principles calculations in the framework of the density functional theory. The study of electronic properties shows the behavior of non-magnetic semiconductors with an indirect gap with a value of 0.5 electron volts for this two-dimensional structure. Also, optical properties such as dielectric function, reflection, energy loss function, absorption coefficient, and optical conductivity are calculated. C3N monolayer is optically anisotropic in z and x direction, which according to the refractive index diagram leads to birefringence, which is a key parameter for this compound's linear optical performance. The results provide a fundamental understanding of the design of composite structures used in nanodevices based on two-dimensional advanced materials. The linear response approach along the symmetric points calculates the phonon dispersion diagram. The results indicate the absence of negative modes in the phonon spectrum, indicating that the structure is dynamically stable. Investigating the thermoelectric properties of the C3N monolayer using the semi-classical Boltzmann theory shows that this monolayer has a value coefficient (ZT) close to one at room temperature and temperatures lower than room temperature. As a result, it can be proposed as a candidate for thermoelectric applications.

Many non-classicality indicators are used to measure the quantum effects of different systems. Kenfack's and Sadeghi's non-classicality indicators are introduced regarding the amount of Wigner distribution function's negativities and interferences in phase space quantum mechanics, respectively. Kenfack’s non-classicality indicator is used for cases just in the Wigner representation, whereas Sadeghi’s non-classicality indicator is effectively, applied for some real distribution functions. In this paper, we investigate these non-classicality indicators for the entangled photon number states in the Wigner, Husimi, and Rivier representations. It is shown that for a two-level entangled state, Sadeghi's indicator has more benefits to measure entanglement with respect to Kenfack's indicator. For the two-level entangled state, we also show a correspondence between Sadeghi's non-classicality indicator and the Von Neumann entropy. It is also shown that for the superposition of the squeezed number state and ground number state, the squeezing parameter affects the entanglement feature and Sadeghi's non-classicality indicator increases with the increase of the squeezing parameter.

Introduction: We report an investigation on collaboration practices in research papers published in the most prestigious English-medium astrophysics journals. Method: We propose an evaluation method based on three numerical indicators to study and compare, in absolute terms, three different types of collaboration (international, national and local) and authors' mobility on the basis of co-authorship. Analysis: We analysed 300 randomly selected research papers in three different time periods and used the student's t-test to determine whether the paired two-sample differences observed were statistically significant or not. Results: International collaboration is more common than national and local collaboration. International, national and local authors' mobility and intra-national collaboration do not seriously affect the indicators of the principal levels of collaboration. International collaboration and authors' mobility are more relevant for authors publishing in European journals, whereas national and intra-national collaboration and national mobility are more important for authors publishing in US journals. Conclusions: We explain the observed differences and patterns in terms of the specific scope of each journal and the socio-economic and political situation in both geographic contexts (Europe and the USA). Our study provides a global picture of collaboration practices in astrophysics and its possible application to many other sciences and fields would undoubtedly help bring into focus the really big issues for overall research management and policy.

Using the experimental results and data, the thermodynamic characteristics and thermal analysis of the electrical arc of torch electrodes and energy deposition in the waste-incinerator primary designed chamber were investigated. The temperature of arc in the intermediate electrode which is called the float nozzle was measured at 7000-8000 Kelvin based on the input power of 2 kW. The plasma plume temperature implied to be lower than the arc temperature according to the cold gas flow in the nozzle. The efficiency of energy transferring to the plasma plume is dependent on the geometrical electrode and nozzle design, and gas flow rate. After ten seconds, the chamber temperature was measured at 1193 Kelvin by thermocouple with the performance of electrical elements and plasma torch. The chamber temperature increasing in an adiabatic process was calculated at 1230 Kelvin after this time. According to the isothermal approach, the heat flow rate, and conduction loss calculation, the chamber temperature was obtained at about 900-1000 Kelvin. Using two approaches with inevitable approximations, the calculated temperature ranges for arc and plasma plume energy estimation have reasonable compatibility and this led to the road map of optimization and development for future torch planning and waste-incinerator chamber design.

In this work, considering the moment theory propagation of the laser beam with relativistic intensity in thermal quantum plasma is studied. Using the Maxwell equation and dielectric function obtained by the quantum hydrodynamic model, the mathematical equation for the laser beam width parameter is achieved and solved numerically by the fourth-order Runge-Kutta method. The results show that the stronger self-focusing effect is found in the moment theory compared to paraxial approximation. Also, similar to paraxial approximation, with growing Fermi temperature, plasma density and laser intensity, the oscillation frequency of the beam width parameter increases and focusing length decreases which means improving the self-focusing effect. Furthermore, it is seen that behaviors of the critical radius are not similar in the two theories, as in the moment theory, with increasing laser intensity, critical radius decreases until it becomes independent of the beam intensity, but in the paraxial approximation, the critical radius after a minimum value is enhanced with increasing laser intensity.

Gene expression is known as a phenomenon that shapes human life. This very complex phenomenon is formed from two stages: transcription and translation. In this study, we used the Nose-Hoover thermostat to model the effect of ambient temperature on gene expression since temperature regulates the biological clock of living systems. We have used the Lyapunov exponent approach to investigate the effect of control parameters on gene expression, including the degradation rates of messenger RNA and proteins, and to find critical points (phenomenon boundary limits), mRNA, and protein level boundary values. The rate of degradation in the process of protein synthesis has been investigated with the help of the Lyapunov exponent approach. According to this study, the optimal temperature for the production of mRNA molecules by Escherichia coli bacteria is 306 Kelvin. The study also used the chaos approach to show that the faster the mRNA molecules are degraded, the more they are transcribed, and the more chaotic the system becomes.

Entanglement plays a fundamental role in the field of quantum computing and quantum communication. In real conditions, a physical system is never isolated and inevitably interacts with its surroundings. Temperature is one of these effects that mainly reduces entanglement. In real conditions, the system is at a non-zero temperature, which will lead to a mixed state. Therefore, in the present work, the combined thermal entanglement of electron spin-oscillation in an anisotropic two-dimensional quantum dot is investigated using the negativity criterion. The results show that the combined entanglements are strongly dependent on the changes of the controllable parameters, such as the Rashba parameter and the magnetic field. The thermal entanglement between the spin and the assembly of oscillators is zero at absolute zero temperature and reaches a maximum with increasing temperature and then tends to zero asymptotically. This temperature, at which the amount of entanglement reaches its maximum value, can be controlled by changing the magnetic field and the coupling of the Rashba parameter. These two factors also control the rate of reaching the asymptotic state. These results provide a way to control the degree of entanglement between electron degrees of freedom, which is a fundamental requirement of quantum information processing.

In the last two decades, photonic crystals and structures that are based on them (photonic structures) have been examined and have been widely utilized in various optical applications. In this article, a theoretical and numerical model for the propagation of electromagnetic waves in multilayer dielectric structures is developed. The propagation of ultra-short light pulses in multilayer media and microresonators is investigated, and the energy reflection and transmission coefficients depending on the parameters of the environment and duration of the optical pulse are calculated. A method for calculating the transmission and reflection spectra of one-dimensional photonic crystal based on FDTD modeling with the emission of ultra-short optical pulses is proposed. To calculate the transmission and reflection spectrum of a one-dimensional photonic crystal and to simulate the propagation of ultra-short light pulses, in multilayer dielectric structures and microresonators, based on the numerical solution of Maxwell's equations with the finite difference approximation in the space-time domain, is performed.

In this study, The surface plasmon excitations in a dimer structure of closely spaced metallic nanospheres with different radii are investigated using the hydrodynamic model. Initially, an expression was derived to calculate this structure's multipolar surface plasmon excitations. Subsequently, the surface plasmon excitations in the dipole approximation were examined.The surface plasmon excitations in a dimer structure of closely spaced metallic nanospheres with different radii are examined using the hydrodynamic model in this study. It has been observed that the energy of in-phase modes is lower than that of out-of-phase modes in longitudinal or transverse excitations. Furthermore, at each separation distance between the nanospheres, the energy difference between in-phase and out-of-phase longitudinal modes is greater than that of transverse modes. The results show that with an increase in the separation distance between the nanospheres, the energies of in-phase modes increase, and the energies of out-of-phase modes decrease. At large separation distances, two plasmon modes are obtained, with the higher energy mode corresponding to the smaller nanosphere and the lower energy mode corresponding to the larger nanosphere. Finally, the local limit results are presented for comparison.

In this study, the optical and electronic properties of bulk and nano-layer of zinc selenide (ZnSe) and zinc sulfide (ZnS) are investigated. The calculations for solving the many-body Schrodinger equations are performed in the framework of density functional theory using the WIEN2K computational package. The Engel-Vosko and gradient generalized approximation (GGA) treat the exchange-correlation potential. To investigate the electronic and optical properties of zinc selenide and zinc sulfide nano layers, the electronic band structure and the real and imaginary parts of complex dielectric function for the bulk and nano-layer with different thicknesses are calculated and compared. The results of electronic band structures show that the energy band gap of zinc selenide and zinc sulfide nano-layers with various thicknesses decreases to zero and are metal. In contrast, the bulk of zinc selenide and zinc sulfide compounds are semiconductors. The results also show that for each compounds the static dielectric function for the perpendicular and parallel direction to the nano-layer surface is different from the bulk static dielectric function. Comparison between the real parts of complex dielectric function for the bulk and nano-layer shows that absorption of electromagnetic radiation for the ZnSe and ZnS nano-layer in comparison to corresponding bulk results occur in lower energies.

In this study, we carry out a qualitative and quantitative analysis of abbreviations in 300 randomly collected research paper titles published in the most prestigious European and US-based Astrophysics journals written in English. Our main results show that the process of shortening words and groups of words is one of the most characteristic and recurrent features in Astrophysics research paper titling construction. In spite of the convenience of abbreviations as a mechanism for word-formation, some of them may pose certain difficulties of understanding and/or misinterpretation because of their specificity, ambiguity, or overlapping. To overcome these difficulties, we propose a series of options which with no doubt would lead to a better interaction among the different branches of Astrophysics in particular and of science in general and would definitely improve how research is currently performed and communicated.

Many materials have been explored for the purpose of creating structures with high radiative cooling potential, such as nanocellulose-based structures and nanoparticle-based coatings, which have been reported with environmentally friendly attributes and high solar reflectance in current literature. They each have their own advantages and disadvantages in practice. It is worth noting that nanocellulose-based structures have an absorption peak in the UV wavelengths, which results in a lower total solar reflectance and, consequently, reduce radiative cooling capabilities. However, the interwoven-fiber structure of cellulose gives high mechanical strength, which promotes its application in different scenarios. The application of nanoplatelet-based coatings is limited due to the need for high volume of nanoparticles to reach their signature high solar reflectance. This requirement weakens the polymer matrix and results in more brittle structures. This work proposes a dual-layer system, comprising of a cellulose-based substrate as the bottom layer and a thin nanoparticle-based radiative cooling paint as the top layer, where both radiative cooling potential and mechanical strength can be maximized. Experimental and theoretical studies are conducted to investigate the relationship between thickness and reflectance in the top coating layer with a consistent thickness of the bottom layer. The saturation point is identified in this relationship and used to determine the optimal thickness for the top-layer to maximize material use efficiency. With the use of cotton paper painted with a 125 μm BaSO4-based layer, the cooling performance is enhanced to be 149.6 W/m2 achieved by the improved total solar reflectance from 80 % to 93 %.

In this paper, using 2D PIC simulation, the electron acceleration in the bubble regime has been investigated in the interaction of a short high-power laser pulse with an underdense plasma with a density ramp. Due to the laser pondermotive force, a plasma wave and its corresponding electric field are formed in the plasma. The electrons injected in the focusing and acceleration region of the plasma wave field can get energy from the wave and are accelerated to high energies of the Giga-electron-Volt range. The simulation results show that with increasing the plasma density gradient, the phase speed of the generated plasma wave increases, and the corresponding wavelength decreases. This causes the displacement of the plasma wave focusing and acceleration region and ultimately increases the acceleration length in the acceleration process. Considering a laser pulse with dimensionless intensity amplitude , pulse duration , and plasma with density ramp length ,the plasma wave accelerating electric field with amplitude was generated. The results of this work can be crucial in choosing an appropriate plasma profile to design the laser-plasma accelerator system for obtaining the Giga-electron-Volt energy gain in a short time.

Weyl semimetals show special quantum states of matter, which have nontrivial topological features and very interesting and unique applications in the spintronics industry. One method of making these materials is the use of alloying method. In this paper, the alloys are constructed using the first-principles methods. After study of their stability, their structural, electronic, and topological properties have been studied. To study the structural and electronic properties of the alloys, the Wien2k package, based on density functional theory, has been used. Furthermore, the topological properties of the alloys have been calculated using the Wanniertools packages, based on the tight-binding method. Calculations show that the alloys, in the absence of spin-orbit coupling, have crossing points with fourfold degeneracy and band inversion. Therefore, they are topological Dirac semimetal. Considering the spin-orbit coupling, it is seen that alloys with concentrations of x = 0, 0.25, 0.5, 0.75 change to the normal semimetal by opening the band gap; but, the alloy with x = 1 concentration changes to the topological Weyl semimetal with 16 Weyl fermions couple. The full area of the first Brillouin zone (FBZ) was scanned to find the positions of the Weyl points. The results show that the Weyl points, with chirality of either +1 or -1, were scattered in the FBZ with the central symmetry, but all of them are far from the high-symmetry paths of FBZ. Furthermore, the surface state properties, like Fermi arcs, were calculated and studied for the NbSb Weyl semimetal using the Wanniertools computational packages.

The design of optical sensors in the THz region for application in various fields of biological and medical sciences has significantly expanded in the last two decades. In this paper, we proposed an optical sensor using two dimensional and periodic structure of graphene rings on the dielectric substrate. The surface plasmon resonance mechanism was employed to design the refractive index sensor. First, by changing the geometric parameters of the structure, the optimal parameters for the sensor performance have been extracted. Then, the sensor's sensitivity has been checked regarding the change in the refractive index of the surrounding environment. The sensitivity of the proposed simple structure is 11.2 μm/RIU and is larger than previous works. Also, increasing the refractive index of the measured medium diminished the quality of sensor operation. The proposed sensor can be used to detect environmental air pollution by proper calibration. The Lumerical software which is based on the finite difference time domain method is used to this end.

Invasive alien plant species (IAPS) may cause threats to native biodiversity in ecosystems. Researchers have been investigating all the possible ways that they can be used effectively for other purposes. Since IAPS are capable of forming cellulose fibre nets, in this research, papers were made from three different types of IAPS (Japanese knotweed, giant goldenrod, and black locust). This research examined these IAPS papers and their effectiveness when used as printing substrates. In comparison to commercial office paper, the differences in basic, surface, optical, and microscopic properties were measured. As a widely used technology, inkjet printing was applied. We tested a commonly used sans-serif typeface (which has been established as being more legible than other typefaces in previous research) in three different type sizes (i.e., 8, 10, and 12 pt). According to the results, paper made from IAPS could offer some usable properties and acceptable legibility, especially when printing typefaces with specific attributes, such as moderate counter size, higher x-height, and minimal differences in the letter stroke width, are used. An appropriate typographic tonal density should be achieved in combination with an adequate letter size, e.g., 10 pt type size when a sans-serif typeface is used.

This review explores circular economy principles in regard to ethanol production from paper-mill sludge. Environmental sustainability and renewability over fossil fuels make second generation ethanol an attractive energy source in a rapidly growing population and consumption world. Paper sludge (PS), a by-product of the pulp and paper (P&P) industry, can no longer be recycled for paper production and is mainly disposed of in landfills. Therefore, it poses a major environmental challenge. However, it has shown potential as a valuable raw material for ethanol production, along with other pulp and paper products, due to its abundant availability and high cellulosic content. This waste-to-energy (WtE) technology for ethanol production is proposed as an alternative, aligning with circular economy concepts to maximize resource efficiency and minimize waste. This review underlines the circular economy aspects of bioethanol production within paper mill sludge management systems. Circular economy principles applied to ethanol production from PS offer a promising avenue for sustainable biofuel development that not only addresses waste management challenges but also enhances the overall environmental performance of biofuel production. Furthermore, economic benefits are described, highlighting the potential for job creation and community development.

Abstract Health monitoring using wearable artificial intelligence (AI) sensors with sensing and cognitive capabilities has garnered significant attention. The development of self‐contained AI sensors that can operate with low power consumption, akin to the human brain, is necessary. Physical reservoir computing (PRC), which mimics the human brain using physical phenomena, offers a low‐power consumption architecture. Nevertheless, creating a flexible and easily disposable sensors using PRC capable of processing optical signals with sub‐second response times suitable for biological signals presents a challenge. In this study, a disposable and flexible paper‐based optoelectronic synaptic devices are designed, which are composed of nanocellulose and ZnO nanoparticles, for PRC. This device exhibits synaptic photocurrent in response to optical input. To assess its performance, a classification and time‐series forecasting tasks are conducted. The memory capacity of short‐term memory task, indicating the device's ability to store past information, is 1.8. The device can recognize handwritten digits with an accuracy of 88%. These results highlight the potential of the device for PRC. In addition, subjecting the device to 1000 rounds of bending do not affect its accuracy. Furthermore, the device burn in a few seconds, much like regular office paper, demonstrating its disposability.

Partial Discharges (PDs) are a significant factor in reducing the insulation life of traction transformers. In recent years, the Acoustic Emission (AE) method has become the most advanced method for detecting PD signals in transformers. The AE method utilizes AE sensors placed on the transformer tank to detect ultrasonic signals emitted by PD and determine the Time Of Arrival (TOA) of the head wave. The windings and cores of a traction transformer consist mainly of metal, which greatly affects the propagation of PD ultrasonic waves. This paper establishes a 110 kV “pressure acoustic, transient” physical field model of the traction transformer with dimensions of 4.63 × 1.48 × 2.84 m3. The model is used to carry out the PD pressure acoustic physical field simulation study of the traction transformer, to clarify the physical characteristics of the ultrasound of the PD defects, and to establish observation points on the transformer tanks to receive ultrasonic time-domain waveforms for PD detection. The simulation results indicate that PD ultrasonic waves exhibit complex propagation characteristics, including reflection, refraction, and reverberation, as they pass through the windings and cores to the observation points. The TOA of the head wave in the ultrasound time-domain waveform is indicated by the first maximum value of the wave crest line. Finally, this paper proposes a multi-level localization method based on the AE method to determine which winding generates the PD in the large-scale traction transformer using only four dynamically moving observation points.

It is essential to establish a multi-dimensional postgraduate quality evaluation system for student assessment and training. This study aimed to explore the construction of the multiindex and hierarchical comprehensive evaluation system for postgraduate training in science and engineering based on the Context, Input, Process, Product (CIPP) model using Analytic Hierarchy Process. It involved 756 postgraduates in physics and engineering who were randomly selected via the Internet. Data were collected from the questionnaire about postgraduates' basic information. After collection, Factor Analysis was used to verify the rationality of the design of second-level and third-level indicators, and adjust the corresponding weights. On this basis, Cluster Analysis was used to classify the training quality of the postgraduates based on their scores on academic ability, basic quality, and social ability indicators. The results revealed that the index system includes 4 first-level indicators,12 second-level indicators and 36 third-level indicators, and different weights being assigned to the indicators according to their influence on the training quality of postgraduates in science and engineering. This study also provides some reference for the quality of science and engineering postgraduate training in Chinese universities by proposing relevant measures, which could be interesting also for international audience.

Assessments are usually thought of as ways for instructors to get information from students. In this work, we flip this perspective and explore how assessments communicate information to students. Specifically, we consider how assessments may provide information about what faculty and/or researchers think it means to know and do physics, i.e., their epistemologies. Using data from students completing assessment questions during one-on-one think aloud interviews, we explore how assessment features did (or did not) impact student engagement with the assessment problems. We analyze video recordings and transcripts to infer the epistemological framings and resources students use while completing introductory-level physics problems. Students' framings tended to be fairly stable, but when shifts occurred, they were triggered by a shift in epistemological resource, which can be activated by assessment feature. This work extends existing work on epistemological framing into the realm of assessment and allows us to consider the effects of assessments on our students' understanding of physics teaching and learning.

Solar winds result from the eruption of plasma streams from the solar corona. This plasma, which consists of proton particles, electrons, X-rays, and radio waves, penetrates the heliosphere and accelerates from the interplanetary space toward the Earth with high kinetic energy and thermal energy. In addition, if it collides with the Earth's atmosphere, it disrupts human life. But despite the Earth's magnetic field and the magnetic reconnection process in this area, the Earth's magnetosphere acts like a shield and prevents these substances from affecting the Earth. To obtain the necessary information to investigate all kinds of phenomena that happen around the Sun, the use of satellite data is the best and most reliable method in terms of accuracy and up-to-date data. The data from the Goes meteorological satellite, LASCO spacecraft, and the Solar Dynamic Observatory are the information that we use in this article to advance our goals. To check the correlation between solar eruptions and changes in the Earth's magnetosphere layer, we use the wavelet analysis method with Morlet's fundamental wave, which is an important tool for processing fluctuations. The results of accurate numerical calculations of this research showed that there is a strong correlation between the magnetic activities of the Sun and the characteristic indices of the Earth's magnetosphere layer, which can affect the Earth's atmosphere as well.

Analyzing the electromagnetic transition strengths is one of the methods of studying the development of atomic nuclei the big-bang, and the fuel cycle of stars in nuclear astrophysics, nuclear synthesis and radiative capture. The study of nuclei with mass number A=11, for example, 11B and 11C, is significant which can be produced by radiative capture of protons by 10B the dependence of the reduced transition probability related to electric quadrupole B[E2] and magnetic dipole B[M1] that occurs in proton radiative capture by 10B nucleus has been investigated. It depends on the excitation energy and spin-parity of the states for the occurrence of E2 and M1 transitions. The theoretical framework of the calculations based On the Woods-Saxon potential model and double folding M3Y has been used to create the ground and excited states of 11C . The results obtained based on each of the mentioned potential models are in good agreement. It was found that B(E2) increases with the increase of excited energy regardless of the spin of excited states. At the same time, B(M1) is very sensitive to the spin of excited states, and also(3/2)-excited states are independent of the energy.

This work aimed to theoretically investigate the operation of the beta voltaic battery with the 14C radio isotopic source and several semiconductors in the p-n junction structure. For this purpose, the saturated thickness of the 14C beta source and energy deposition distribution of beta particles emitted from this source is simulated and calculated in the various semiconductors including the GaAs, GaN, SiC, and diamond using the Monte Carlo code of MCNPX. Regarding the results obtained, the optimized 14C thickness was achieved by 30 micrometers. Then, applying the analytical and numerical model, the relationships between the doping concentration, short circuit current density, open circuit voltage, and output power density were evaluated. The results showed that with and with the diamond as semiconductor, the output power density of designed battery was increased to 9.68 among the other considered semiconductors.

In this article, we will first get acquainted with the absorption and emission optical properties of algae and types of chlorophylls, and then we will examine the optical setup for measuring the photoluminescence light produced by algae, which is the basis for the construction of chlorophyll concentration measuring devices. By examining algae samples in fresh water ponds in Iran and identifying the predominant type of algae in them, spectrometry and concentration measurement were carried out with the help of hemocytometer or neobar lam method. The most important tool for measuring the concentration of algae is chlorophyll-a, which is present in all types of algae with different percentages and has the property of fluorescence, and by measuring the red light resulting from photoluminescence, the amount of chlorophyll-a can be obtained. The main design of a device to measure the amount of chlorophyll-a based on the measurement of photoluminescence light is considered for this purpose and it is used in terms of software and hardware. For this, the process and intensity of light in terms of density was done for calibration, and the disadvantages and advantages of the design were examined. Direct measurement of light, noises, high stability and preparing a logical routine between the data can help to increase and improve the quality and this device becomes a precise tool for measuring chlorophyll and has commercialization capabilities. The stability, reproducibility and high accuracy of the device is one of the advantages of emission (photoluminescence) test methods compared to absorbance methods.

Perovskite solar cells (PSCs) are advancing swiftly due to their remarkable increase in power conversion efficiency (PCE) compared to traditional photovoltaic technologies. The main purpose of this study is to investigate the efficiency of two distinct PSCS structures that use as an inorganic perovskite active layer. The calculations are based on the optoelectronic model of the solar cell and the use of the finite element method to solve the continuity equations for current and charge density. Therefore, the layer thicknesses of different materials (as ETL and Active layer) are modified to find the better power conversion efficiency of these solar cells. The obtained results of simulation calculations illustrate that the first structure FTO/ITO/ /PEDOT: PSS/Au exhibits a maximum power conversion efficiency of 11.37%, with a short circuit current of 14.47 (mA/cm^2) and an open circuit voltage of 0.96 (V) and while the FTO/TiO2/ /Spiro- OMETAD/Au structure shows a maximum power conversion efficiency of 10.57%. The greatest power conversion efficiency for the aforementioned designs is 80 nm for the electron transporting layer is 80 nm and 200 nm for the inorganic active layer, respectively. The results of this article can be useful in the design of new-generation solar cells based on inorganic perovskite layers.

In this research, linear and non-linear optical properties of silver oxide nanoparticles in graphene oxide medium have been investigated. First, graphene oxide is prepared by the improved method of Hammers. Then the synthesis of silver oxide nanoparticles is carried out in the environment of graphene oxide diluted with deionized water, by the electric arc method. The electric arc was applied at 200, 300, 400, and 500 volts with a three-second pulse duration of one minute. The results of ultraviolet-visible spectroscopy show that the resulting solution contains nanoparticles of graphene oxide and silver oxide. Then, a CW 532 nm beam with a maximum power of 300 mW was used to determine the linear absorption of samples. Then, the z-scanning method was used to determine the nonlinear characteristics of the samples. After analyzing the graphs, the refraction and nonlinear absorption coefficients of each sample have been calculated. The results show that with increasing voltage, the concentration of nanoparticles produced in the samples increases and the linear absorption coefficient increases with it. The lowest value of linear absorbance is 1.31 (cm-1) and nonlinear absorbance is negative for all samples and its lowest value is 7.86 *10-3. Also, the nonlinear refractive index is negative for all the samples and its maximum value is 1. 61 *10-14. The thermo-optical coefficients of each of the samples have also been obtained.

This study assesses the mechanical properties of mortars incorporating waste paper sludge-derived cellulose fibers. Compression and flexural tests were carried out on specimens prepared with cellulose fibers at different proportions, ranging from 0% to 2% of the total weight of the solid mortar constituents (cement, sand, and lime). In addition, a comparative analysis was carried out to evaluate the influence of the preparation method on the mechanical properties of the mortars. To this end, two series of mortars were studied: one prepared following a rigorous control of the preparation parameters and the other made without systematic parameter control to simulate typical on-site conditions. Finally, the applicability of both traditional and eco-friendly mortars in the construction of small-scale masonry walls was assessed through compression tests. Overall, the mechanical properties of mortars with cellulose fibers were comparable to those with 0% waste material, regardless of the production process. Regarding the compressive behavior of masonry walls, experimental tests showed significant similarities between specimens made with traditional and eco-friendly mortar. In conclusion, incorporating cellulose fibers into cement-based mortar shows considerable potential for building applications, enhancing the environmental benefits without compromising the mechanical behavior.

We study a three-species cyclic model whose organisms are vulnerable to contamination with an infectious disease which propagates person-to-person. We consider that individuals of one species perform a self-preservation strategy by reducing the mobility rate to minimise infection risk whenever an epidemic outbreak reaches the neighbourhood. Running stochastic simulations, we quantify the changes in spatial patterns induced by unevenness in the cyclic game introduced by the mobility restriction strategy of organisms of one out of the species. Our findings show that variations in disease virulence impact the benefits of dispersal limitation reaction, with the relative reduction of the organisms’ infection risk accentuating in surges of less contagious or deadlier diseases. The effectiveness of the mobility restriction tactic depends on the deceleration level and the fraction of infected neighbours which is considered too dangerous, thus triggering the defensive strategy. If each organism promptly reacts to the arrival of the first viral vectors in its surroundings with strict mobility reduction, contamination risk decreases significantly. Our conclusions may help biologists understand the impact of defensive strategies in ecosystems during an epidemic.

Natural product-based noise-absorbing composite can be an alternative to replace synthetic fiber because of its advantages of high strength, toughness, low price, and abundance to reduce noise. The materials used were pineapple leaf fibers with paper waste. This research aims to study the advantage of natural products to reduce noise by analyzing the coefficient of sound absorption and impact strength to evaluate the absorbing composite. The composites were tested with the Charpy method with ISO 11654 standard and ASTM E23 for sound absorption and impact strength. Sound absorption was carried out using an impedance tube at a frequency range of 250 – 3000 Hz. The volume fraction of pineapple leaf fibers, paper waste, and resin epoxy concentrations were 20% : 30% : 50%, 25% : 25% : 50%, and 30% : 20% : 50%. The thickness for the sound absorption coefficient was 2 cm and 3 cm, while the thickness of the impact strength was 0.5 cm. The highest sound absorption coefficient of pineapple leaf fibers composite for 30% : 20% : 50% volume fraction was 0.788 for sample 2 cm. The highest impact strength for 20% : 30% : 50% volume fraction of the thickness of 0.5 cm was 3.527 J/mm2. The results of the sound absorption coefficient will increase if used more pineapple leaf fibers but it will decrease the impact strength. Based on this research, the pineapple leaf fibers will improve the quality of the composite that can be used as a sound-absorbing material as well. These materials possess the promising potential to decrease waste and are used in industries for a low cost.

In this paper, the behavior of the double pendulums has been studied by considering the effect of initial conditions (angular displacement of the outer pendulum for four cases 12, 30, 90, and 150 degrees) and the influence of system geometry (increasing rod length and mass of the second pendulum), also. After extracting motion equations using the Lagrangian method, in order to deal with the frequency spectrum, traces of bobs, and understanding the system behavior for every case, the Fast Fourier Transform (FFT) technique and Poincare sections have been applied. The obtained results show that the consequence of the rising angular displacement the outer pendulum is to increase the energy level of the system and the change of its behavior from quasi-periodic for angular displacement is less than 90 degrees to chaotic when it is 150 degrees. Therefore, the energy level, in this case, has increased more than twice compared to the first. In addition, it seems a quasi-periodic behavior is forming at the heart of chaotic behavior. On the other hand, the results indicate a very significant effect of geometrics on a system's behavior. According to the calculations, the consequence of increasing the length of the rod of the second pendulum has only led to a different behavior from its similar case (case number 3) completely. however, their energy level is the same. Increasing the mass of the outer by twice not only to lead decrease energy level of the system by 330J but also has shown chaotic behavior (in comparison to the case3).

The topic of "teacher professionalism" is one of the most crucial ones in quality education research. It has a potential to generate results that could inform and hence enhance the practice in classrooms. Thus, research in this field needs reliable instruments to measure the professional knowledge of our teachers to be able to generate reliable results for our research problems. Not many instruments have been developed with regard to this topic. At the same time, an adequate validation of the instrument developed is often missing (Schilling & Hill, 2007). Hence, in a bigger project "ProwiN" (German acronym for professional knowledge of science teachers), test instruments for measuring science teachers' pedagogical, pedagogical content and content knowledge (PK, PCK, and CK) were developed for the subjects biology, chemistry and physics. The present study tested the validity of some of these items which were used to measure the pedagogical content knowledge (PCK) of biology teachers. These items focused on measuring teachers' professional knowledge by analyzing 1) teachers' "knowledge about student understanding" (or lack of understanding) of several topics in biology and 2) "knowledge about instructional strategies" like the use of models or experiments. The content validity of these instruments was examined by think-aloud interviews with American and German Biology teachers (N = 11). This study shows a high content validity for these items. Furthermore, this paper demonstrates the scope for adapting the conceptual framework of these items to measure biology teachers' PCK in other countries.

In the modern day, explosive detection is essential to public safety, and fluorescent small molecules have gained popularity for their quick and accurate detection. Herein, we present the design and synthesis of a series of pyrrolo[1,2-a]quinoxaline-based conjugated small organic fluorophores (PQ-Ph-OH, PQ-Ph-NMe, PQ-Ph-OMe, PQ-Ph-Me, and PQ-Ph-CN) as fluorescence-based sensors for explosive molecules. The sensor molecules were synthesized in good to excellent yields using a dehomologative functionalization strategy. They exhibited excellent photophysical characteristics, which was tunable based on the substituent on the phenyl linker at position 3. DFT studies showed that the pyrroloquinoxaline moiety could act as an on-demand electron donor or acceptor, depending on the phenyl substituent. The molecules also exhibited solid state emission due to twisted geometry around the CC single bond between the heterocyclic scaffold and the phenyl derivative. This resulted in low band intense emission for the synthesized molecules. In the presence of electron-deficient nitroaromatic explosives, all the fluorophores showed excellent fluorescence quenching. Detection limits in the range of 10−4 M were obtained for all the fluorophores. Stern-Volmer plots show high values of binding constants, indicating good interaction between the fluorophores and the explosive molecules. The mechanism of sensing was confirmed by UV-PL spectral overlap and fluorescence lifetime measurements, which suggest a static quenching based on the formation of a ground state complex. Owing to solid state emissions in some of the derivatives, the synthesized molecules were applied to paper strips for spot detection of explosive molecules.

In this research, the symmetry of high-order harmonics resulting from the interaction of a single-layer WSe2 with a linearly polarized laser in both zigzag and armchair directions have been investigated using time-dependent density functional theory in real space. The dependence of the cutoff frequency behavior with the increase of the electric field amplitude and the behavior of the harmonic yield with the laser wavelength has been analyzed. The results show the linear dependence of the cutoff frequency with the electric field and the exponential behavior of the harmonic yield with the laser wavelength. Also, the effect of the input laser field polarization on the high-order harmonic spectrum and harmonic yield has been investigated. Changing the rotation angle of laser polarization to 30 degrees for elliptically polarized light with an ellipticity parameter of 0.1 creates the highest harmonic yield. Also, the results of this research show that by changing the polarization of the input electric field, the polarization of high-order harmonics also changes, which leads to the production of high-order harmonics with different polarization.

At the stagnation time, fuel may impact by a variety of paths, including ablator materials, Hohlraum wall, the interaction of the cone-guided lateral surface with imploding fuel, and cone tip material, releasing and mixing their constituent elements into corona plasma and even inside the pure dense fuel. Here, we have parametrically studied the impact of some well-known ionic impurities such as carbon and gold on the physical condition of DT hot spot ignition. The admissible zone of DT hot spot ignition was plotted on the HsTs plane, and it was shown that for a given percentage of gold impurities, the boundaries of the ignition zone gradually increased with increasing internal implosion velocity and at implosion velocities smaller than 1.7×107 cm/s, there exist two individual ignition islands. In the context of the fast ignition approach to ICF, the areal density of hot spots ignition of deuterium-tritium doped with a small concentration of impurity ions of carbon and gold was then extracted by a non-equilibrium ignition model. Accordingly, for a given value in this range, the contour plot of the allowed areal density parameter in the two-temperature model was plotted on the Te-Ti plane. It has been shown that as the impurity fraction increases, the permissible range of ignition decreases rapidly and the ignition conditions become more difficult. The sensitivity of these changes is directly associated with the coefficient of increase in radiation loss power, which is a function of the parameter of the impurity percentage α and the ionization state of the impurity ion, Zimp. Moreover, in each contour plot, the minimum permissible ignition parameter of ion temperature of contaminated DT fuel is also visible.

A hybrid system including a quantum emitter in the vicinity of a plasmonic core-shell nanostructure in the air is considered, and the spontaneous emission process of the emitter is investigated. The aim is to examine the effect of the plasmonic system on the quantum speed limit and the non-Markovian dynamics of the system. Using the dyadic Green's function of the system, the impact of geometric parameters such as the thickness of the plasmonic nanostructure shell and the distance between the emitter and the nanostructure on the evolution and physical behavior of the desired parameters has been investigated. According to the obtained results, by increasing the distance of the emitter from the nanostructure, the dynamics of spontaneous emission change from non-Markovian to Markovian, and the value of the non-Markovian measure tends to zero. In this condition, the quantum speed limit increases and becomes equal to the evolution time of the system. In addition, as the thickness of the shell increases, the mean value of the non-Markovian measure decreases.

The academic community has witnessed a notable increase in paper publications, whereby the rapid pace at which modern society seeks information underscores the critical need for literature mapping. This study introduces an innovative automatic model for categorizing articles by subject matter using Machine Learning (ML) algorithms for classification and category labeling, alongside a proposed ranking method called SSS (Scientific Significance Score) and using Z-score to select the finest papers. This paper’s use case concerns industry productivity. The key findings include the following: (1) The Decision Tree model demonstrated superior performance with an accuracy rate of 75% in classifying articles within the productivity and industry theme. (2) Through a ranking methodology based on citation count and publication date, it identified the finest papers. (3) Recent publications with higher citation counts achieved better scores. (4) The model’s sensitivity to outliers underscores the importance of addressing database imbalances, necessitating caution during training by excluding biased categories. These findings not only advance the utilization of ML models for paper classification but also lay a foundation for further research into productivity within the industry, exploring themes such as artificial intelligence, efficiency, industry 4.0, innovation, and sustainability.

Expansive soil exhibits significant swellings and shrinkages, which may result in severe damage or the collapse of structures built upon it. Calcium-based admixtures, such as lime, are commonly used to improve this problematic soil. However, traditional chemical additions can increase significant environmental stress. This paper proposes a sustainable solution, namely, the use of lignin fiber (LF) from the paper industry to partially replace lime as an amendment for expansive soils. Both the macroscopic and microscopic characteristics of the lignin fiber-treated expansive soil are extensively studied. The results show that the mechanical properties of expansive soil are improved by using lignin fiber alone. Under the condition of an optimal dosage of 8%, the compressive strength of lignin fiber-modified soil can reach 193 kPa, the shear strength is increased by 40% compared with the untreated soil, and the water conductivity is also improved with the increase in dosage. In addition, compared with 2% lime-modified soil, the compressive strength of 8% lignin fiber- and 2% lime composite-treated expansive soil increased by 50%, the cohesion increased by 12%, and the water conductivity decreased significantly. The microstructure analysis shows that at an 8% lignin fiber content, lignin fibers interweave into a network in the soil, which effectively enhances the strength and stability of the improved soil. Simultaneously, the fibers can form bridges across the adjacent micropores, leading to the merging of pores and transforming fine, dispersed micropores into larger, connected macropores. Lime promotes the flocculation of soil particles, forming larger aggregates and thus resulting in larger pores. The addition of fibers exerts an inhibitory effect on the flocculation reaction in the composite-improved soil. In conclusion, lignin fibers are an effective addition used to partially replace calcium admixture for the treatment of expansive soil, which provides a sustainable and environmentally friendly treatment scheme for reducing industrial waste.

Background: High-stakes assessments, such the Graduate Records Examination, have transitioned from paper to computer administration. Low-stakes research-based assessments (RBAs), such as the Force Concept Inventory, have only recently begun this transition to computer administration with online services. These online services can simplify administering, scoring, and interpreting assessments, thereby reducing barriers to instructors' use of RBAs. By supporting instructors' objective assessment of the efficacy of their courses, these services can stimulate instructors to transform their courses to improve student outcomes. We investigate the extent to which RBAs administered outside of class with the online Learning About STEM Student Outcomes (LASSO) platform provide equivalent data to tests administered on paper in class, in terms of both student participation and performance. We use an experimental design to investigate the differences between these two assessment conditions with 1310 students in 25 sections of 3 college physics courses spanning 2 semesters. Results: Analysis conducted using hierarchical linear models indicates that student performance on low-stakes RBAs is equivalent for online (out-of-class) and paper-and-pencil (in-class) administrations. The models also show differences in participation rates across assessment conditions and student grades, but that instructors can achieve participation rates with online assessments equivalent to paper assessments by offering students credit for participating and by providing multiple reminders to complete the assessment. Conclusions: We conclude that online out-of-class administration of RBAs can save class and instructor time while providing participation rates and performance results equivalent to in-class paper-and-pencil tests.

This paper investigates the effects of cold plasma radiation on the percentage, velocity, average germination per day, germination index, and prose and growth of green cumin roots. A factorial experiment was performed in a randomized design in 5 repetitions. Test factors included pretreatment of cold plasma irradiation time at 0, 3, 6, 9, and 12 minutes by 7 and 14 kV and 800 Hz plasma generators. The results of this work showed that the treatment time and the applied voltage of cold plasma significantly affect the percentage, velocity, average of germination per a day, germination index, and prose and root of the green cumin seed. Among all treatments, a dose of treatment with time of 6 minutes at a peak voltage of 14 kV had the greatest effect on the referred characteristics, except increasing root in which plasma treatment with a dose of 3 minutes has the most effect. Cold plasma has been generated with a dielectric barrier discharge (DBD) is a hand-made and designed in on desk dimensions, in which air is used as plasma active gas.

The main aim of this study was to determine students' perceptions toward web-based versus paper-based homework and identify any differences based on homework performance score and grade point average. A 21-item perception of online vs. paper-based homework survey was administered to 103 students (54 were male and 49 were female) in general physics-1 classes. Results of the study indicated that there was not a statistically significant difference in physics grade point average scores; however, there was a statistically significant difference in homework performance (average) scores based on assigned homework groups. Overall, students' perception of web-based homework testing was positive. Finally, some tentative recommendations are posed. (Contains 3 tables.)