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The current study examines the strength and transport properties of reclaimed asphalt pavement (RAP) inclusive pervious concrete (PC) pavement mixes containing various industrial and agricultural wastes such as silica fume (SF), fly ash (FA), and bagasse ash (BGA). Apart from a conventional PC mix (containing natural aggregates) and a 100% RAP inclusive PC mix, seven different mixes were developed by mixing 100% RAP aggregates with SF (5 and 10%), FA (10 and 15%), and BGA (5, 10, and 15%) as partial replacements for ordinary Portland cement. The above-mentioned PC pavement mixes were investigated for density, porosity, permeability, compressive strength, modulus of rupture, and abrasion resistance. The interconnected pore structure of conventional PC and RAP-PC pavement mixes was investigated using 2D image analysis and X-Ray microcomputed tomography. Based on the laboratory results, it can be stated that the inclusion of RAP significantly improves the transport properties of PC pavement mixes with increased porosity and permeability values. This was primarily due to a more interconnected pore matrix and lesser isolated voids in the RAP-PC pavement mix. The addition of SF could only improve the strength parameters (compressive strength and modulus of rupture) of the RAP-PC pavement mix. In contrast, BGA inclusion was observed to improve its transport properties (porosity and permeability). Furthermore, the inclusion of SF, FA, and BGA in a 100% RAP-PC mix improved abrasion resistance. When compared to the conventional PC pavement mix, incorporating RAP aggregates blended with SF, FA, and BGA can reduce the production cost of 1 m3 PC by 30–61% and lower CO2 emissions by 13–21%. However, considering the strength and transport property requirements of PC mixes, as well as the economic and environmental viability, the present investigation recommends using 5% SF, 10% FA, and 10% BGA in a 100% RAP-PC pavement mix. [ABSTRACT FROM AUTHOR]

Lattice vibrations or phonons play an important role in determining material properties, including thermal conductivity. To model the phenomenon accurately and efficiently, the most important factors governing phonon physics need to be identified, for example, polarization branches. Research continues into many aspects of the fundamental physical processes involved in phonons and into possible applications of these processes in modern physics. One of the most interesting controversies in the thermal properties of graphene involves the importance of out-of-plane acoustic phonons. The need for clarity in understanding this importance dictates that the thermal conductivity of graphene should be evaluated in various circumstances. The nanoscale heat conduction properties of graphene are studied by iteratively solving the Boltzmann transport equation and rigorously treating the normal and Umklapp collisions in the frame of three-phonon interactions. This captures the mechanistic aspects of thermal conductivity by revealing what phonon branches are present. The thermal conductivity is evaluated in different crystallite sizes and at different frequencies and temperatures. The results indicated that out-of-plane acoustic phonons become increasingly important in the frame of three-phonon interactions. The out-of-plane acoustic branch dominates thermal transport whereas the other acoustic branches make small contributions. The importance of this branch is generally attributed to the high density of states and restrictions governing anharmonic effects. The three-phonon normal and Umklapp processes must be clearly accounted for and the contribution from optical branches is not negligible at higher temperatures. The results have implications in the quest for predictive and quantitative calculations of thermal conductivity. [ABSTRACT FROM AUTHOR]

We investigate the energy band structure and transport properties of electrons in superlattice structure based on semi-Dirac material with one-dimensional periodic potentials of square barriers. The influence of different parameters on transmission probability in superlattice structure is studied. It is found that two new Dirac points are formed in the superlattice structure by adjusting the gap parameter. The position of the new Dirac points can be regulated by changing the size of the potential barrier, the ratio of well width to barrier width, and the gap parameter. Some forbidden bands appear in the transmission probability, the location and width of the forbidden bands can be regulated by changing the system parameters. [ABSTRACT FROM AUTHOR]

Two-dimensional (2D) semiconductors have attracted much attention regarding their use in flexible electronic and optoelectronic devices, but the inherent poor electron mobility in conventional 2D materials severely restricts their applications. Using first-principles calculations in conjunction with Boltzmann transport theory, we systematically investigated the Si-doped 2D β-Ga2O3 structure mediated by biaxial strain, where the structural stabilities were determined by formation energy, phonon spectrum, and ab initio molecular dynamic simulation. Initially, the band gap values of Si-doped 2D β-Ga2O3 increased slightly, followed by a rapid decrease from 2.46 eV to 1.38 eV accompanied by strain modulations from −8% compressive to +8% tensile, which can be ascribed to the bigger energy elevation of the σ* anti-bonding in the conduction band minimum than that of the π bonding in the valence band maximum. Additionally, band structure calculations resolved a direct-to-indirect transition under the tensile strains. Furthermore, a significantly high electron mobility up to 4911.18 cm2 V−1 s−1 was discovered in Si-doped 2D β-Ga2O3 as the biaxial tensile strain approached 8%, which originated mainly from the decreased quantum confinement effect on the surface. The electrical conductivity was elevated with the increase in tensile strain and the enhancement of temperature from 300 K to 800 K. Our studies demonstrate the tunable electron mobilities and band structures of Si-doped 2D β-Ga2O3 using biaxial strain and shed light on its great potential in nanoscale electronics. [ABSTRACT FROM AUTHOR]

The ternary transition metal boride Fe2AlB2 is a unique ferromagnetic "MAB" phase that demonstrates a sizable magnetocaloric effect near room temperature—a feature that renders this material suitable for magnetic heat pump devices (MHP), a promising alternative to conventional vapor compression technology. Here, we provide a comprehensive review of the material properties of Fe2AlB2 (magnetofunctional response, transport properties, and mechanical stability) and discuss alloy synthesis from the perspective of shaping these materials as porous active magnetic regenerators in MHPs. Salient aspects of the coupled magnetic and structural phase transitions are critically assessed to elucidate the fundamental origin of the functional response. The goal is to provide insight into strategies to tune the magnetofunctional response via elemental substitution and microstructure optimization. Finally, outstanding challenges that reduce the commercial viability of Fe2AlB2 are discussed, and opportunities for further developments in this field are identified. [ABSTRACT FROM AUTHOR]

The potential of hydrogen as an energy source has positioned hydrogen storage as a prominent research domain in the current era. Innovative perovskite compounds have emerged as a focal point for investigating hydrogen storage applications. In this study, we have investigated the RbXH 3 (X = Mg/Ca/Sr/Ba) perovskite hydrides by density functional theory (DFT). Our exploration encompasses the analysis of electronic structures, mechanical stability, elastic properties, and optical and thermoelectric response. The cubic crystal structures of RbXH 3 are revealed, with lattice constants of 4.13, 4.54, 4.82, and 5.17 Å for X = Mg, Ca, Sr, and Ba, respectively. Electronic structure calculations indicate ionic bonding with a wide bandgap reduced with increasing size of X. Mechanical stability, essential for meeting the Born stability criterion, is scrutinized, whereas Pugh criteria suggest a ductile and hard nature for these materials. Thermoelectric characteristics regarding electrical and thermal conductivity, Seebeck coefficient, and power factors are elaborated. The figure of merit emphasizes their suitability for thermoelectric devices. The Gravimetric ratios indicate the hydrogen storage capability, potentially contributing to various transportation and power applications. [Display omitted] • This manuscript presents a pioneering investigation into the potential of RbXH 3 (X = Mg/Ca/Sr/Ba) perovskites for hydrogen storage, offering a fresh perspective on sustainable energy materials. • A state-of-the-art first-principle density functional theory (DFT) based calculations are carried out to comprehensively explore the structural, electronic, and hydrogen storage properties of these alkaline metal-based hydrides. • Structural stability of RbXH 3 perovskites, shedding light on their suitability as stable materials for practical applications in hydrogen storage systems. [ABSTRACT FROM AUTHOR]

Mass diffusion coefficient measurement techniques with high temporal and spatial resolution have become essential for the research and development of leading-edge technology in a wide range of cross-disciplinary fields, but cannot be achieved using conventional methods. We provide a comprehensive review of the state-of-the-art theoretical and experimental investigations on Soret forced Rayleigh scattering (SFRS), a grating excitation technique (GET) for measuring the mass diffusion coefficient of binary liquid mixtures. SFRS utilizes the Soret effect to create micrometer-order periodic spatial concentration modulation in a sample due to the absorption of an optical interference grating generated by two intersecting heating laser beams. The decay of the concentration modulation by the mass diffusion process within several milliseconds is detected by the diffraction of a probing beam. The theoretical considerations regarding deviations from the ideal mass diffusion conditions are the effects of: (1) the Gaussian beam intensity distribution, (2) the light absorbing material and (3) the cell wall. The proper settings for the optical system are also analyzed, e.g., the effect of coherency and polarization of the heating laser and the effect of the z-direction length of the interference region. We also consider the frame of reference, center of gravity invariance and effect of convection, which are particularly important for mass diffusion experiments. Using the correct implementation of the theory, the optimal SFRS apparatus design and its appropriate use are described in detail. Finally, two successful applications of SFRS are demonstrated using visible light laser heating and mid-wavelength infrared gas laser heating. [ABSTRACT FROM AUTHOR]

In this paper, molecular dynamics (MD) simulations and machine learning (ML) methods are combined to obtain the transport properties, such as viscosity and thermal conductivity, of five basic elements, which are computationally hard to obtain at the nanoscale and extremely demanding to estimate accurately through an experimental procedure. Starting from an experimental database from literature sources, we extend the (P‐T) space on which the transport properties are calculated by employing MD simulations and ML predictions, in a synergistic mode. Results refer to all fluid states (gas, liquid, supercritical), under ambient and supercritical conditions, suggesting an alternative path that can be accurately followed to bypass expensive experiments and costly numerical simulations. Nine different ML algorithms are exploited and assessed on their prediction ability, with tree‐based architectures achieving increased accuracy on the implied data set. The proposed computational platform runs fast in a common python Jupyter environment, both for MD and ML, and can be adjusted and extended for the calculation of material properties both in interpolation and extrapolation applications. [ABSTRACT FROM AUTHOR]

An unusual self‐assembly pattern is observed for highly ordered 1500‐nm‐thick films of monodisperse 13‐nm‐sized colloidal PbSe quantum dots, originating from their faceted truncated cube‐like shape. Specifically, self‐assembled PbSe dots exhibited attachment to the substrate by <001> planes followed by an interconnection through the {001} facets in plan‐view and {110}/{111} facets in cross‐sectional‐view, thus forming a cubic superlattice. The thermoelectric properties of the PbSe superlattice thin films are investigated by means of frequency domain thermoreflectance, scanning thermal probe microscopy, and four‐probe measurements, and augmented by computational efforts. Thermal conductivity of the superlattice films is measured as low as 0.7 W m−1 K−1 at room temperature due to the developed nanostructure. The low values of electrical conductivity are attributed to the presence of insulating oleate capping ligands at the dots’ surface and the small contact area between the PbSe dots within the superlattice. Experimental efforts aiming at the removal of the oleate ligands are conducted by annealing or molten‐salt treatment, and in the latter case, yielded a promising improvement by two orders of magnitude in thermoelectric performance. The result indicates that the straightforward molten‐salt treatment is an interesting approach to derive thermoelectric dot superlattice thin films over a centimeter‐sized area. [ABSTRACT FROM AUTHOR]

V2VI3-based materials are the best materials for thermoelectric cooling devices. Interest in studying the transport properties of V2VI3 thin films has increased after it was found that V2VI3 belong to the class of topological insulators. In this work, the dependences of electrical conductivity, Hall coefficient, charge carrier mobility on magnetic field and temperature of Bi2(Te0.9Se0.1)3 films with thicknesses 48 and 130 nm were measured and interpreted. The transport properties in the thin-film and bulk states were compared. The boundaries between weak and strong magnetic fields were determined. The obtained results are important for solid-state physics development and practical applications. [ABSTRACT FROM AUTHOR]

The utilization of Bi-based superconductors in magnetic field environments is limited due to their anisotropic structure and lack of efficient magnetic flux pinning sites. Therefore, to enhance the performance of Bi-based superconductors in a magnetic field, this study presents the preparation of Bi2212 high-temperature superconducting thin films with varying NiO doping levels on SrTiO 3 (STO) single crystal substrates with different concentrations of NiO seed layers via the self-assembly method. Additionally, phase purity, crystal structure, surface morphology, and transport properties were thoroughly analyzed. According to the results, the NiO seed layers prepared on the STO substrates presented epitaxial growth characteristics, with the NiO second phase in the Bi2212 matrix growing epitaxially along the seed layers. As NiO doping slightly broadens the phase formation temperature range of Bi2212 superconducting thin films, the self-assembly method can be utilized to prepare NiO nanorods with epitaxial growth in Bi2212 thin films. Notably, the self-assembled NiO-doped Bi2212 thin film demonstrated higher critical current carrying capacity, with its J c reaching 6.28 × 104 A/cm2 at 10 K in self-field. This provides a technical reference for improving the performance of high-temperature superconducting thin films under a high magnetic field. [ABSTRACT FROM AUTHOR]

The exploration of performance and prediction of environmentally friendly refrigerant physical properties represents a critical endeavor. Equilibrium molecular dynamics simulations were employed to investigate the density and transport properties of propane and ethane at ultra-low temperatures under evaporative pressure conditions. The results of the density simulation of the evaporation conditions of the blends proved the validity of the simulation method. Under identical temperature and pressure conditions, increasing the proportion of R170 in the refrigerant blends leads to a density decrease while the temperature range in which the gas-liquid phase transition occurs is lower. The analysis of simulated results pertaining to viscosity, thermal conductivity, and self-diffusion coefficient reveals heightened deviation levels within the phase transition temperature zone. This increase in deviation attributed to intensified molecular activity. In terms of uncovering the physical mechanism of gas-liquid phase transition, the work illustrates the macroscopic phenomenon of the intensified existing disorder during phase transitions at the molecular level. Molecular dynamics simulations analyzing the thermophysical properties of refrigerant blends from a microscopic point of view can deepen the comprehension of the thermal optimization of refrigeration processes. [ABSTRACT FROM AUTHOR]

Due to its large hole mobility, organic rubrene (C42H28) has attracted research questions regarding its applications in electronic devices. In this work, extensive first-principles calculations are performed to predict some temperature- and doping-dependent properties of organic semiconductor rubrene. We use density functional theory (DFT) to investigate the electronic structure, elastic and transport properties of the orthorhombic phase of the rubrene compound. The calculated band structure shows that the orthorhombic phase has a direct bandgap of 1.26 eV. From the Vickers hardness (1.080 GPa), our calculations show that orthorhombic rubrene is not a super hard material and can find useful application as a flexible semiconductor. The calculated transport inverse effective mass and electronic fitness function show that the orthorhombic rubrene crystal structure is a p-type thermoelectric material at high temperatures.

We present structural, electronic, magnetic, elastic and transport properties of tetragonal Mn2PtSn (MPS) bulk material in stannite (ST) phase, we will use a FP-LAPW method based on DFT under GGA, TB-mBJ and GGA+U as implemented in the WIEN2k code. From the ferromagnetic state, band structure (spin-down/spin-up channel) calculations reveal an indirect bandgap/zero-bandgap. Mn2PtSn shows inverse tetragonal crystal structures with ferromagnetic spin order at zero temperature. The elastic stability criterion shows that the MPS crystal satisfies the mechanical stability under applied at 0 GPa. The related mechanical properties such as bulk modulus (B), shear modulus (G), Young's modulus (E), and Poisson's ratio (ν) are also studied for polycrystalline of MPS; the calculated B/G value (B/ G = 2. 9 6) shows that MPS behaves in a ductile manner. Hence, this study of transport properties suggests their potential thermoelectric applications at high temperatures. To our knowledge, the results obtained show that this ternary alloy is advantageous for materials employed in spintronic devices. [ABSTRACT FROM AUTHOR]

Lead halide perovskites have been replaced by the environmentally acceptable and effective lead‐free double perovskite material. Double perovskites are innovative compounds for sustainable energy and budding substitutes to organic as well as lead‐based solar cells. In the current study, it has been expounded on the structural, electronic, thermoelectric, as well as thermodynamic characteristics of newly designed double perovskites In2TiX6 (X = Br, I) by means of ab‐initio computations relied on the FP‐LAPW tactics and semi‐classical Boltzmann transport theory with PBE‐GGA as exchange correlation potential. To obtain accurate value of band gaps (1.294 eV and 1.025 eV), TB‐mBJ approximation has been used along with PBE‐GGA. The best combinations of both compounds have spectroscopic limited maximum efficiency (SLME) values 33.96% and 31.63%, that are appropriate for solar cell absorbers, at 300 K, respectively. We have also computed Debye temperature θD$$ \left({\theta}_D\right) $$ and Grüneisen parameter γ$$ \left(\gamma \right) $$ to find the lattice thermal conductivity for both the investigated alloys. Thermoelectric properties have been labeled by Seebeck coefficient, electrical as well as thermal conductivities, and figure of merit. The peak values of Seebeck coefficient of 248 μV/K and 202 μV/K are observed for In2TiBr6 and In2TiI6 respectively in the p‐type regions. Attained results illustrates that the investigated In2TiX6 may be contender in thermoelectric due to their high figure of merit in low as moderate temperatures. Our results suggest that these materials are viable for use in thermoelectric devices. [ABSTRACT FROM AUTHOR]

Proton-conducting oxides based on lanthanum ytterbates (LaYbO3) have been proposed as promising electrolytes due to their high chemical stability in aggressive atmospheres. To improve the transport properties of LaYbO3, a strategy of oxygen deficiency creation by acceptor-type doping is usually employed. However, the acceptor-doping strategy has some limitations related to the low solubility limit of the introduced dopants. To further improve the ionic transport of already doped LaYbO3, two strategies—isovalent doping (chemical factor) and sintering temperature (technological factor)—are deliberately used in the present work. The La0.9Sr0.1Yb0.8R0.2O3–δ (R = In, Er, Y, Dy) were synthesized using the standard citrate-nitrate technology. X-ray diffraction analysis showed that all the samples are single-phase and have an orthorhombic structure with space group of Pna21. Increasing the sintering temperature from 1400 to 1500 °C almost doubles the average grain size of the samples; as a result, the ceramics sintered at 1500 °C have higher grain boundary and total conductivities than those of the ceramics sintered at 1400 °C. Among the La0.9Sr0.1Yb0.8R0.2O3–δ ceramics sintered at 1500 °C, the Dy-substituted material exhibits the highest grain boundary and total conductivities that confirms dopant type affects the electrolyte microstructure which, in turn, affects its electrochemical response. Therefore, the La0.9Sr0.1Yb0.8Dy0.2O3–δ composition can be considered the most conductive among the studied series. [ABSTRACT FROM AUTHOR]

All current theories concerning the conductivity of polyelectrolytes ignore the dielectric friction effect undergone by the polyion chains according to their conformation. Indeed, Manning's theory is limited to the case of stretched chains and only takes into account hydrodynamic, electrophoretic and ionic frictions; while scaling approach theories take into account the formation of different types of blobs within the chain but are restricted to hydrodynamic and electrophoretic frictions. In this work, we present a different approach that explains the variation of the equivalent conductivity of polyions having coiled or almost or completely stretched conformations and that takes into account the four frictions. In addition, the introduction of the dielectric friction effect allowed us to interpret the dependency of the equivalent conductivity of a polyion λP,X on the nature of its counterions X. A likely correlation between this effect and Hofmeister's is discussed. [ABSTRACT FROM AUTHOR]

We present a new wide-range correlation for the viscosity of ethene based on critically evaluated experimental data. The viscosity correlation is valid from the triple point to 450 K and up to 195 MPa. The average absolute percentage deviation of the fit for the primary data (including the critical region) is 1%, with a bias of 0.2%, The estimated uncertainty of the correlation in the gas and supercritical phases at pressures up to 195 MPa is 2.5% (at the 95% confidence level). For the dilute gas (pressures up to 0.1 MPa) in the temperature range 296 K to 450 K, the uncertainty is 0.5%. For the liquid phase at pressures up to 5.5 MPa the estimated uncertainty is 5.3%. The correlation includes a term for the critical enhancement that is significant only in a very narrow region very close to the critical point. It is less than 1% outside of the region around the critical point from 279.80 K ≤ T ≤ 290.27 K to 140.79 kg⋅m−3 ≤ ρ ≤ 293.08 kg⋅m−3. [ABSTRACT FROM AUTHOR]

Due to its large hole mobility, organic rubrene (C42H28) has attracted research questions regarding its applications in electronic devices. In this work, extensive first-principles calculations are performed to predict some temperature- and doping-dependent properties of organic semiconductor rubrene. We use density functional theory (DFT) to investigate the electronic structure, elastic and transport properties of the orthorhombic phase of the rubrene compound. The calculated band structure shows that the orthorhombic phase has a direct bandgap of 1.26 eV. From the Vickers hardness (1.080 GPa), our calculations show that orthorhombic rubrene is not a super hard material and can find useful application as a flexible semiconductor. The calculated transport inverse effective mass and electronic fitness function show that the orthorhombic rubrene crystal structure is a p-type thermoelectric material at high temperatures. [ABSTRACT FROM AUTHOR]

Premature degradation of concrete, caused by frost damage, has been associated with inadequate transport properties and poor resistance to deicing salt. In this study, transport properties and deicing salt resistance of various kinds of ultrahigh-performance concrete (UHPC) containing Type V portland cement, fly ash, and microsilica were investigated. Seven combinations of cementitious materials (one reference, three binary, and three ternary) were used to batch UHPCs using a water-to-cementitious material ratio (w/cm) of 0.21. The aggregate-to-cementitious material ratio (Va/Vcm) of 1.20 was kept constant for all mixtures. The investigated transport properties included water absorption, volume of permeable voids, water penetration, rapid chloride penetration, and surface resistivity. The transport properties of the plain UHPCs were also compared to those of the corresponding steel fiber–reinforced UHPCs. The test results showed that the transport properties and deicing salt resistance of the studied binary and ternary UHPCs improved with the inclusion and increases in microsilica, replacing a portion of cement. The addition of steel fiber had a minor effect on strength and transport properties and a moderate increase in deicing salt resistance of the studied UHPCs. While rapid chloride penetration and surface resistivity tests were found appropriate to assess chloride transport through the studied plain UHPCs, both tests were deemed unsuitable for the companion steel fiber–reinforced UHPCs. [ABSTRACT FROM AUTHOR]

Halide perovskites possess ultra-low thermal conductivity and show high potential for thermoelectric devices. The chemical properties and molecular structure of halide perovskite materials are not completely stable under ambient conditions, which hinders their use in thermoelectric generators. Changes in the properties of bulk halide perovskite thermoelectrics are accompanied by partial phase transitions and surface oxidation processes. In this paper, we conducted a comprehensive study of the transport and structural properties of CsSnI3, which were pristine by vacuum melting followed by spark plasma sintering. The research results on the electrical transport of these materials revealed that exposure to an inert atmosphere does not deteriorate stability and the properties of the materials remain unchanged. However, prolonged exposure to air leads to a significant degradation of the electrical transport properties. Contrary to thin-film samples, the shift to the double perovskite structure from the perovskite one is limited to a specific surface layer. This change significantly influences the electrical transport of the material while maintaining the essential properties of both perovskite types. [ABSTRACT FROM AUTHOR]

[Display omitted] Developing low-power FETs holds significant importance in advancing logic circuits, especially as the feature size of MOSFETs approaches sub-10 nanometers. However, this has been restricted by the thermionic limitation of SS , which is limited to 60 mV per decade at room temperature. Herein, we proposed a strategy that utilizes 2D semiconductors with an isolated-band feature as channels to realize sub-thermionic SS in MOSFETs. Through high-throughput calculations, we established a guiding principle that combines the atomic structure and orbital interaction to identify their sub-thermionic transport potential. This guides us to screen 192 candidates from the 2D material database comprising 1608 systems. Additionally, the physical relationship between the sub-thermionic transport performances and electronic structures is further revealed, which enables us to predict 15 systems with promising device performances for low-power applications with supply voltage below 0.5 V. This work opens a new way for the low-power electronics based on 2D materials and would inspire extensive interests in the experimental exploration of intrinsic steep-slope MOSFETs. [ABSTRACT FROM AUTHOR]

As a highly regarded superconducting material with a concise layered structure, MgB2 has attracted significant scientific attention and holds vast potential for applications. However, its limited current-carrying capacity under high magnetic fields has greatly hindered its practical use. To address this issue, we have enhanced the superconducting performance of MgB2 by incorporating inhomogeneous phase nanostructures of p-n junctions with electroluminescent properties. Through temperature-dependent measurements of magnetization, electronic specific heat, and Hall coefficient under various magnetic fields, we have confirmed the crucial role of inhomogeneous phase electroluminescent nanostructures in improving the properties of MgB2. Experimental results demonstrate that the introduction of electroluminescent inhomogeneous phases effectively enhances the superconducting performance of MgB2. Moreover, by controlling the size of the electroluminescent inhomogeneous phases and optimizing grain connectivity, density, and microstructural uniformity, we can further improve the critical temperature (TC) and flux-pinning capability of MgB2 superconducting materials. Comprehensive studies on the physical properties of MgB2 superconducting structures added with p-n junction electroluminescent inhomogeneous phases also confirm the general effectiveness of electroluminescent inhomogeneous phases in enhancing the performance of superconducting materials. [ABSTRACT FROM AUTHOR]

In this work, we propose a comprehensive experimental study of the diffusion of nickel ions in combination with different cyclodextrins as carrier molecules for enhanced solubility and facilitated transport. For this, ternary mutual diffusion coefficients measured by Taylor dispersion method are reported for aqueous solutions containing nickel salts and different cyclodextrins (that is, α-CD, β-CD, and γ-CD) at 298.15 K. A combination of Taylor dispersion and other methods, such as UV-vis spectroscopy, will be used to obtain complementary information on these systems. The determination of the physicochemical properties of these salts with CDs in aqueous solution provides information that allows us to understand solute–solvent interactions, and gives a significant contribution to understanding the mechanisms underlying diffusional transport in aqueous solutions, and, consequently, to mitigating the potential toxicity associated with these metal ions. For example, using mutual diffusion data, it is possible to estimate the number of moles of each ion transported per mole of the cyclodextrin driven by its own concentration gradient. [ABSTRACT FROM AUTHOR]

In this paper, optical and transport properties of Polyvinyl Alcohol/Silver incorporated Zinc Oxide (PVA/Ag–ZnO) nanocomposites of varying Ag–ZnO nanoparticles content prepared by solution casting method are studied to explore their multifunctional applications. The nanocomposites are characterized using X-ray diffraction, Scanning electron microscope, Energy-dispersive X-ray analysis, UV–Visible spectroscopy and Fourier transform infra-red spectroscopy. The UV–visible spectra showed zero transmittance in the UV region with increasing Ag–ZnO nanoparticles content in the PVA matrix suggesting that the nanocomposites could be used as a potential UV shielding material. The optical band gap energy decreases from 5.77 to 1.54 eV with increasing Ag–ZnO nanoparticles content in the PVA matrix. Frequency- and temperature-dependent dielectric measurement of the samples reveals maximum dielectric constant at PVA/15 wt% Ag–ZnO nanocomposite. Dielectric loss results showed a lossless behaviour at higher frequencies (< 0.2), suggesting that the prepared samples are suitable for use in high-frequency applications. The AC conductivity studies reveal that electrical conduction mechanism in the nanocomposites is governed by the correlated barrier hopping mechanism. Activation energy calculation indicates the involvement of two different types of conduction mechanism in the samples. The Nyquist plot for all the samples is fitted using the equivalent circuit model. The studied results show that the PVA/Ag–ZnO nanocomposites can serve as potential candidates for optoelectronic and electronic device application. [ABSTRACT FROM AUTHOR]

The microporous layer (MPL) plays an important role in water and thermal management of proton exchange membrane fuel cells (PEMFCs). An in-depth investigation of the mechanical compression effect on transport properties in the MPL can help optimize cell performance. In this work, the microstructure of the MPL is numerically reconstructed and the finite element method is applied to simulate mechanical behavior. Besides, the distribution of stress-strain, porosity, and pore size in the MPL under ten different levels of mechanical compression strains are studied. Lastly, the pore-scale model is employed to investigate the effective transport properties of the MPL as a function of compression strain. The analysis reveals that as the MPL strain increases from 0% to 40%, there is a 29% decrease in porosity, a 50% reduction in average pore diameter, a 60% decrease in effective gas diffusivity, a 100% increase in tortuosity, and an 80% increase in electrical and thermal conductivity. With the escalation of mechanical compression, both the magnitude and uniformity of stress-strain-displacement concurrently rise. Mechanical compression strains below 20% exhibit a lesser impact on transport properties. Beyond this threshold, exceeding the 20% compression strain point, mechanical stress assumes a critical role in influencing MPL transport properties. • The realistic microstructure of the microporous layer is reconstructed numerically. • The properties of each component of the microporous layer are fully considered. • The finite element method is utilized to simulate mechanical stresses. • Pore-scale simulations are utilized to obtain the effective transport properties. • Critical compressive strain points are identified to guide assembly optimization. [ABSTRACT FROM AUTHOR]

This scientific study employs the Taylor dispersion technique for diffusion measurements to investigate the interaction between sulfamerazine (NaSMR) and macromolecular cyclodextrins (β-CD and HP-β-CD). The results reveal that the presence of β-CD influences the diffusion of the solution component, NaSMR, indicating a counterflow of this drug due to solute interaction. However, diffusion data indicate no inclusion of NaSMR within the sterically hindered HP-β-CD cavity. Additionally, toxicity tests were conducted, including pollen germination (Actinidia deliciosa) and growth curve assays in BY-2 cells. The pollen germination tests demonstrate a reduction in sulfamerazine toxicity, suggesting potential applications for this antimicrobial agent with diminished adverse effects. This comprehensive investigation contributes to a deeper understanding of sulfamerazine–cyclodextrin interactions and their implications for pharmaceutical and biological systems. [ABSTRACT FROM AUTHOR]

The present article summarizes experimental and theoretical considerations required for a proper use of dynamic light scattering (DLS) for the measurement of transport properties of fluids. It addresses not only recent advancements of the method, but also aims to provide recommendations to researchers who intend to apply the technique in the future. As outlined in this study, DLS is based on the analysis of scattered light governed by microscopic statistical or periodic fluctuations that originate from the thermal movement of molecules and/or particles at macroscopic thermodynamic equilibrium. The dynamics of these hydrodynamic fluctuations in the bulk of fluids or at their phase boundaries are related to the underlying diffusive processes and, thus, to the associated transport properties, and are reflected by the time-dependent correlation function of the scattered light intensity. The fundamentals of this type of detection, known as photon correlation spectroscopy (PCS), will be discussed in the present contribution in some more detail. It is emphasized that the experiments need to be designed carefully in accordance with theory in order to assign the measurement signals to the corresponding hydrodynamic fluctuations. If the necessary conditions are fulfilled, DLS allows the accurate determination of several transport properties including kinematic and dynamic viscosity, thermal diffusivity, mutual diffusivity, and sound attenuation, which may be accessed together with other thermophysical properties such as speed of sound and surface or interfacial tension. In some instances, also the simultaneous determination of several transport properties is possible. With the exception of the sound attenuation, expanded uncertainties for the mentioned transport properties down to 1 % can be achieved for various types of fluid systems over a wide range of thermodynamic states up to elevated temperatures and pressures as well as in the vicinity of critical points. This performance and versatility of the DLS technique is documented in the present study by highlighting measurement examples from recent thermophysical property research on different classes of working fluids relevant for process and energy technology. [ABSTRACT FROM AUTHOR]

Semiconductors with direct band gaps are outstanding for their use in most optoelectronic devices specifically for solar cells. Here we studied the optoelectronic, thermodynamic, and thermoelectric features of novel MgACu3Se4 (A = Sc, Y) semiconductors. Cutting-edge computations that employs density functional theory is used. The predicted density of state plots validated the electronic band structure results. A direct type of energy gap with a semiconducting behavior was noticed from the electronic band profiles of both materials. The significant optical response for the incident photon energy range of 0–14 eV is also revealed and discussed in detail. By using the quasi-harmonic Debye model, we additionally examined the thermodynamic characteristics of these quaternary systems and analyzed how their cell volume, Debye temperature, heat capacity, thermal expansion coefficient, and Grüneisen constant change over the pressure and temperature range from 0 up to 20 GPa and 0 up to 1200 K, respectively. Furthermore, the important thermoelectric transport parameters were evaluated and discussed for their thermoelectric application. [ABSTRACT FROM AUTHOR]

A microporous layer (MPL) is a transition layer with a porous material structure, located between the gas diffusion layer (GDL) and catalyst layer (CL) in a proton exchange membrane fuel cell (PEMFC). It not only significantly improves electron transfer and heat conduction in membrane electrode assembly, but also effectively manages liquid water transport to enhance the fuel cell performance. The MPL is usually coated on one side of the GDL. The fragile nature of MPL makes it challenging to characterize the effective transport properties using experimental methods. In this study, a stochastic numerical method is implemented to reconstruct the three-dimensional microstructure of an MPL consisting of carbon particles and PTFE. The reliability of the MPL reconstructed model is validated using experimental data. The relationship between the effective transport properties and the compression strain is obtained using the Pore Scale Model (PSM), while the relationship between the liquid water saturation and capillary pressure is solved by Lattice Boltzmann Method (LBM). The effective transport properties in the MPL are then imported into the two-phase flow fuel cell model. It is found that the effective transport parameters in MPL obtained by PSM and LBM can improve the accuracy of the model calculation. This study provides an effective method to reconstruct the microstructure of MPL that can generate precise MPL transport parameters for utilization in various PEMFC performance prediction models.

Influence mechanism of various ion chelators on the mechanical, transport, and microstructure properties of cement-based materials was explored. The ion chelators included pentasodium diethylenetriamine pentaacetate, tetrasodium ethylenediaminetetraacetate, sodium hexametaphosphate and tetrasodium glutamate diacetate, with a dosage of 1 % of the cement mass. The effect of ion chelators on the mechanical, transport, and pore structure properties was evaluated by compressive, sorptivity, and mercury intrusion porosimetry (MIP) tests. The composition and microstructure of hydration products were studied by scanning electron microscope (SEM) and X-ray diffractometer (XRD). Test results indicated that four ion chelators reduced the mechanical and transport properties, and increased the porosity of specimens at 3 d and 7 d. And four ion chelators improved the mechanical and transport properties, and reduced porosity at 28 d and 56 d. The fundamental reason for the differences in the basic properties of cement-based materials caused by the types of ion chelators is that different ion chelators possess various calcium chelating capacities and stability of calcium complexes, which leads to different impact on the complexation substitution reaction process. Moreover, compared to the stability of calcium complexes, the influence of calcium chelating ability on the basic properties of specimens is more significant in the early curing ages.

Ground Granulated Blast-Furnace Slag (GGBS) and silica fume (SF) are frequently utilized in gel materials to produce environmentally sustainable concrete. The blend of the two components contributes to an enhancement in the pore structure, which, in turn, increases the mechanical strength of the material and the compactness of the pore structure and decreases the permeability, thereby improving the durability of the concrete. In this study, the pore structures of GGBS and SF blends are assessed using Nuclear Magnetic Resonance (NMR) and Mercury Intrusion Porosimetry (MIP) tests. These methodologies provide a comprehensive evaluation of the effect of GGBS and SF on the pore structure of cementitious materials. Results showed that the addition of SF and GGBS reduces the amount of micro-capillary pores (10 < d < 100 nm) and the total pore volume. The results indicate that the transport properties are related to the pore structure. The incorporation of SF reduced the permeability of the concrete by an order of magnitude. The pore distribution and pore composition had a significant effect on the gas permeability. The difference in porosity obtained using the MIP and NMR tests was large due to differences in testing techniques. [ABSTRACT FROM AUTHOR]

The discovery of ductile Ag2(S, Se, Te) materials opens a new avenue toward high‐performance flexible/hetero‐shaped thermoelectrics. Specifically, the cubic‐structured materials are quite attractive by combining remarkable plasticity, decent thermoelectric figure of merit (zT), and no phase transition above room temperature. However, such materials are quite few and the understanding is inadequate on their mechanical and thermoelectric properties. Enlightened by the high‐entropy principles, a series of pseudo‐ternary Ag2S‐Ag2Se‐Ag2Te alloys is designed and comprehensive diagrams of composition‐structure‐plasticity‐zT are compiled. Subsequently, the compositional region for the cubic phase is outlined. As a high‐entropy example featuring with anion‐site alloying and disordered Ag ions, Ag2‐xS1/3Se1/3Te1/3 materials exhibit impressively large elongations of 60–97%, ultralow lattice thermal conductivities of ≈0.2 W m−1 K−1, and decent zT values of 0.45 at 300 K, 0.8 at 460 K. The materials can be readily rolled into thin foils, showing excellent flexibility. Finally, a six‐leg in‐plane device is fabricated, achieving an output voltage of 13.6 mV, a maximal power of 12.8 µW, and a power density of 14.3 W m−2 under the temperature difference of 30 K, much higher than the organic counterparts. This study largely enriches the members of cubic ductile inorganic materials for the applications in flexible and hetero‐shaped energy and electronic devices. [ABSTRACT FROM AUTHOR]

In this manuscript, structural, electronic, magnetic, and thermoelectric aspects of AFeO3 (A = Ca, Sr, Ba) have been calculated by means of the Full‐Potential Linearized Augmented Plane Wave Method (FP‐LAPW) using spin‐polarized Density Functional Theory (DFT). The calculated structural parameters have been found to be in good resemblance with previously available work. Enthalpy of formation and cohesive energy along with tolerance factor confirms structural stability. Electronic properties by Trans Blaha modified Becke–Johnson potential (TB‐mBJ) suggest metallic behavior in the spin‐up channel and semi‐conducting behavior in the spin‐down channel that supports half‐metallic behavior with mixed covalent and ionic bonding. Density of States (DOS) analysis confirms the major contribution of Fe‐3d‐states in the conduction band and O‐2p states in the valence band. The half‐metallic nature is further confirmed by the integer value of the total magnetic moment. The real and imaginary parts of dielectric functions, optical conductivities, absorption coefficients, reflectivity, and energy loss function have been calculated to evaluate suitability for optical applications. Thermoelectric properties with temperature range 300–900 K against chemical potential including figure of merit, Seebeck coefficient, thermal conductivities, and power factor, were examined using BoltzTraP code. Findings suggest that AFeO3 (A = Ca, Sr, Ba) compounds suitable for spintronic, thermoelectric as well as energy harvesting applications. [ABSTRACT FROM AUTHOR]

Safety concerns caused by organic liquid electrolyte in lithium battery might limit its application. Li 7 La 3 Zr 2 O 12 is a promising electrolyte for solid-state lithium batteries due to its high ionic conductivity and interfacial stability with lithium. The influence of Ta doping on the structure, transport property and ionic conductivity of Li 7−x La 2.95 Yb 0.05 Zr 2−x Ta x O 12 (0 ≤ x ≤ 0.2) has been investigated. Ta drives some Li ions from 24d to 96 h site and simultaneously optimizes the size of Li ion transport pathway. This structure modification increases the mobility, jump rate, and diffusion coefficient of lithium ion. Besides, the densification and grain contact have also been enhanced. The ionic conductivity of Li 6.85 La 2.95 Yb 0.05 Zr 1.85 Ta 0.15 O 12 reaches 1.07 × 10−3 S cm−1 at 30 °C. The solid-state battery assembled with Li 6.85 La 2.95 Yb 0.05 Zr 1.85 Ta 0.15 O 12 exhibits high critical current density of 1.1 mA cm−2 and discharge capacity of 166.7 mAh g−1, indicating that Li 6.85 La 2.95 Yb 0.05 Zr 1.85 Ta 0.15 O 12 is a competitive solid electrolyte for solid-state lithium batteries. • High conductivity is achieved in Yb-Ta codoped LLZO by optimizing Li+ occupation. • Enhanced ionic conductivity and grain contact result in high critical current density. • Optimized size of ion diffusion pathway improves the transport behavior of Li ion. [ABSTRACT FROM AUTHOR]

The influence of various energetic particles and electron injection on the transport of minority carriers and non-equilibrium carrier recombination in Ga2O3 is summarized in this review. In Ga2O3 semiconductors, if robust p-type material and bipolar structures become available, the diffusion lengths of minority carriers will be of critical significance. The diffusion length of minority carriers dictates the functionality of electronic devices such as diodes, transistors, and detectors. One of the problems in ultrawide-bandgap materials technology is the short carrier diffusion length caused by the scattering on extended defects. Electron injection in n- and p-type gallium oxide results in a significant increase in the diffusion length, even after its deterioration, due to exposure to alpha and proton irradiation. Furthermore, post electron injection, the diffusion length of an irradiated material exceeds that of Ga2O3 prior to irradiation and injection. The root cause of the electron injection-induced effect is attributed to the increase in the minority carrier lifetime in the material due to the trapping of non-equilibrium electrons on native point defects. It is therefore concluded that electron injection is capable of "healing" the adverse impact of radiation in Ga2O3 and can be used for the control of minority carrier transport and, therefore, device performance. [ABSTRACT FROM AUTHOR]

Structure complexity, adequate electronic character and congenital lower thermal conductivity of zintl phases result in designing thermoelectrics of tremendous efficiency. Such qualities of zintl phases embolden us to present a detailed study of SmMg2X2 (X = P, As, Sb, Bi) zintl compounds by first principles. The structural characteristics fit well with the existing data. Electronic properties of titled compounds are scrutinized by adopting PBE-GGA, TB-mBJ and hybrid (YS-PBE0) potentials. The band structure calculations through TB-mBJ and hybrid (YS-PBE0) proclaim the semiconducting behavior of compounds and there is a shrinkage of band gap by changing X anion from P to Bi. The density of states (DOS) calculation reveals that there is a major contribution of Sm-f states and Mg atom in valence band while in conduction band, the prominent role is offered by Sm-d states and p states of X anion. Similarly, the temperature-dependent thermoelectric properties are scrutinized by using BoltzTraP2 code embedded within WIEN2k software for with and without spin–orbit coupling (SOC) and also through hybrid (YS-PBE0) functional. SOC, but even more hybrid functional, has been shown to have a significant effect on the transport behavior. Optimized values of carriers’ concentration are achieved which subsidize thermoelectric parameters like power factor (PF), Seebeck coefficient (S) and thermoelectric figure of merit (ZT) at elevated temperature. The compounds show excellent thermoelectric performance in the studied temperature range. [ABSTRACT FROM AUTHOR]

Polyimides are a polymer class that has been extensively investigated as a membrane material for gas separation owing to its interesting permselective properties in a wide range of operation temperatures and pressures. In order to improve their properties, the addition of different filler types is currently studied. p-tert-Butylcalix[n]arene macrocycles (PTBCs) with different cavity sizes (PTBC4, PTBC6, PTBC8) were used as fillers in a commercial thermoplastic polyimide, with a concentration in the range 1–9 wt%, to develop nanocomposite membranes for gas separation. The selected macrocycles are attractive organic compounds owing to their porous structure and affinity with organic polymers. The nanocomposite membranes were prepared in the form of films in which the polymeric matrix is a continuous phase incorporating the dispersed additives. The preparation was carried out according to a pre-mixing approach in a mutual solvent, and the solution casting was followed by a controlled solvent evaporation. The films were characterized by investigating their miscibility, morphology, thermal and spectral properties. The gas transport through these films was examined as a function of the temperature and also time. The results evidenced that the incorporation of the chosen nanoporous fillers can be exploited to enhance molecular transport, offering additional pathways and promoting rearrangements of the polymeric chains. [ABSTRACT FROM AUTHOR]

This paper presents the effect of salt concentration on the electrochemical, thermal, and structural properties of the solid polymer electrolyte (SPE) prepared with the polymer sodium carboxymethylcellulose (NaCMC) and the salt sodium triflate (NaCF3SO3). The electrolyte was prepared in the form of membranes using solution cast technique. Deionized water was used as a common solvent for both the precursor materials. The membranes were characterized using electrochemical impedance spectroscopy (EIS), Fourier‐transform infrared spectroscopy (FTIR), X‐ray diffraction (XRD), and differential scanning calorimetry (DSC). XRD results show reduction in crystallinity of the electrolyte with an increase in the salt concentration. The FTIR result confirms polymer‐salt interaction. The ionic conductivity of the electrolyte membrane was found to be dependent on the concentration of NaCF3SO3. The maximum ionic conductivity of the SPE membranes was observed to be 1 × 10−4 Scm−1 at room temperature (36°C). DSC results show an increase in glass transition temperature (Tg) with increasing salt concentration. The total ionic transference number of the highest conducting sample was found to be ~1, which shows that the conductivity of SPE membranes is predominantly due to the transport of ions. [ABSTRACT FROM AUTHOR]

The present work gives an insight into the structural, thermal, and electrical analysis of novel nanocomposite solid polymer electrolyte films prepared using the solution casting technique by incorporating cobalt oxide nanoparticles into methyl cellulose‐magnesium acetate polymer electrolyte matrix. The impact of ceramic oxide on the complexation of the salt with the polymer chain is evident from FTIR analysis. The crystallinity of the electrolyte systems decreases upon the incorporation of nanofiller into the matrix. Electrochemical Impedance Analysis of the samples shows enhancement in the conductivity of the electrolytes. Nanocomposite electrolyte systems with 2 wt% (5.93 × 10−4 S/cm) and 3 wt% (5.77 × 10−4 S/cm) of cobalt oxide exhibit maximum room temperature ionic conductivity compared to other electrolyte systems. DSC thermogram reveals the creation of free volume in the matrix with the incorporation of the filler. A primary battery is fabricated using the nanocomposite electrolyte system with 3 wt% of the nanofiller, and its open circuit potential and discharge characteristics have been analyzed. Highlights: Novel nanocomposite SPEs with cobalt oxide were prepared via solution casting.FTIR and XRD studies revealed modification in the microstructure.Cobalt oxide incorporation enhanced ionic conductivity of SPE.A primary battery fabricated using the highest conducting SPE. [ABSTRACT FROM AUTHOR]

Chloride salts that have abundant reserves own good thermal stability in high-temperature components of solar systems and thermal storage devices. However, the high corrosiveness makes their experimental study difficult, especially at high temperatures. In this work, the ionic structure and transport properties of the binary chloride NaCl-CaCl2 system are investigated by applying density functional theory, machine learning, and molecular dynamics simulation methods. The maximum errors of energy and force for deep potential molecular dynamics are 5.02 × 10−4 eV/atom and 0.02 eV·Å–1, respectively. The ionic structure of the NaCl-CaCl2 system is mainly determined by the coordination requirements of calcium and chloride ions. As the temperature decreases, the coordination number increases, and the network structure of ions becomes more compact, resulting in a positive temperature dependence of the self-diffusion coefficient of ions in the system and a negative temperature dependence of the viscosity. The simulation results are in good agreement with the experimental data. The deep potential molecular dynamics simulation method can effectively solve the problem of finite scale effects faced by the ab initio molecular dynamics (AIMD) simulation method in predicting transport properties, while achieving the computational accuracy of AIMD and thus can better predict transport properties such as self-diffusion coefficient and viscosity. This is of great importance in accurately predicting the thermal performance of molten salts and their enhancement for solar and thermal storage systems. [ABSTRACT FROM AUTHOR]

Transcritical cycles working with CO2‐based mixtures gain considerable attention due to thermodynamic efficiency gain compared to pure sCO2 in hot environments. Previous literature works prove that the adoption of CO2 mixtures provides a reduction of the levelized cost of electricity in concentrated solar power applications and medium–high temperature heat recovery. However, for techno‐economic analysis and heat exchanger design, proper evaluation of transport properties of the CO2‐based mixtures in power cycle conditions is necessary. Herein, it deals with the analysis of the proper transport properties models for CO2 mixtures to assess their actual thermal behavior. A literature review on transport properties models, and their validation with available experimental data, proves that the friction theory is suitable for CO2 blended with dopants having high molecular complexity. The impact of the different model selection on the recuperator sizing, considering optimized power cycle conditions, is assessed on the CO2 mixtures with hexafluorobenzene and decane: The TRAPP and Chung–Lee–Starling models are imported from Aspen Plus, while the friction theory model is implemented and calibrated in an in‐house MATLAB code. The optimal design of the recuperator for the CO2 + C6F6 mixture in a 100 MWel power block coupled with a solar power plant located in Sevilla is carried out. [ABSTRACT FROM AUTHOR]

The gas diffusion layer (GDL), as the bridge to reactants and electrons in PEMFC, is a carbon-based porous component and would be deformed under compression to induce changes in the distributions of reactants and the corresponding performances of PEMFC; therefore, unmasking the impacts of assembly pressure on the distribution of the reactants in GDL is significant to improve the performance of PEMFC. In the present article, the structural response of GDL to assembly pressure was first studied; the variations in transport properties of GDL and the reactant distributions induced by assembly pressure were then discussed; the impacts on the dynamic performances of PEMFC were finally investigated. From the results, assembly pressure was found to have different effects on the regions of GDL under the rib and channel, significant gaps in GDL porosity and/or GDL permeability existed near the rib/channel transition region to worsen the inhomogeneity of reactants. Suffering assembly pressure, the distribution of current density became uneven, and the current density near the rib-channel border seriously rose to the aggravated risk of MEA thermal damage. Furthermore, the power density at specific efficiencies was raised under certain assembly pressures, which meant suitable assembly pressure(s) existed for better output performances of PEMFC.