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A merged potential energy surface (PES) is introduced for CO + CO collisions by combining a recent full-dimensional ab initio PES [Chen et al. J. Chem. Phys. 153, 054310 (2020)] and analytical long-range multipolar interactions. This merged PES offers a double advantage: it retains the precision of the ab initio PES in describing the van der Waals well and repulsive short range while providing an accurate physical description of long-range interaction; it significantly reduces the computational time required for trajectory integration since the long-range portion of the ab initio PES (involving numerous neural network fitting parameters) is now replaced by the analytical model potential. Based on the present merged PES, mixed Quantum-Classical (MQC) calculations, which capture quantum effects related to vibrational motion, align with a range of experimental data, including transport properties, vibrational energy transfer between CO and its isotoplogues, as well as rate coefficients for V–V and V–T/R processes. Notably, the original ab initio PES yields V–T/R rate coefficients at low temperatures that are significantly higher than the experimental data due to the artificial contribution of its unphysical long-range potential. In addition to conducting extensive MQC calculations to obtain raw data for V–V and V–T/R rate coefficients, we employ Gaussian process regression to predict processes lacking computed MQC data, thereby completing the considered V–V and V–T/R datasets. These extensive rate coefficient datasets, particularly for V–T/R processes, are unprecedented and reveal the significant role played by V–T/R processes at high temperatures, emphasizing the necessity of incorporating both V–V and V–T/R processes in the applications. [ABSTRACT FROM AUTHOR]

The unique physical properties of carbyne, a novel carbon nanostructure, have attracted considerable interest in modern nanotechnology. While carbyne synthesis has been accomplished successfully using diverse techniques, the underlying mechanisms governing the carbon monoxide-dependent catalytic synthesis of endohedral carbyne remain poorly understood. In this simulation-based study, we investigate the synthesis of endohedral carbyne from carbon and carbon monoxide radicals in the presence of a nickel catalyst inside double-walled carbon nanotubes with a (5,5)@(10,10) structure. The outcome of our investigation demonstrates that the incorporation of the carbon atom within the Nin@(5,5)@(10,10) model system initiates the formation of an elongated carbon chain. In contrast, upon the introduction of carbon monoxide radicals, the growth of the carbyne chain is inhibited as a result of the oxidation of endohedral nickel clusters by oxygen atoms after the initial steps of nucleation. Our findings align with prior theoretical, simulation, and experimental investigations, reinforcing their consistency and providing valuable insights into the synthesis of carbyne-based nanodevices that hold promising potential for future advancements in nanotechnology. [ABSTRACT FROM AUTHOR]

The impact of a time-varying external magnetic field on carbon nanotubes has been studied using Maxwell's equations in the mentioned articles. However, the Maxwell's equations are erroneously presented in the papers. The incorrect Maxwell's equations, their derivatives, and the Lorentz force equations have all been examined in this work. In this article, we have endeavored to ensure that the equations are formatted correctly and have made an effort to do so. We have made an effort to intuitively correct the equations' errors. We did not comment on the other portions of the mentioned articles; instead, we restricted ourselves to the examination of the impact of Maxwell's equations and Lorentz force equations. [ABSTRACT FROM AUTHOR]

BACKGROUND: The hard double‐walled structure of Ganoderma lucidum spore powder (GLSP) is difficult for the human body to digest, so it is very important to break the wall of GLSP. In this study, the wall of GLSP was broken by mechanical milling at room temperature (MM‐R) and ultra‐fine grinding at low temperature (UFG‐L), respectively. RESULTS: Compared with MM‐R, UFG‐L could better retain the sporangium powder's morphological and structural integrity. During in vitro digestion, compared with unbroken GLSP, the released amounts of polysaccharides and triterpenes from broken GLSP were significantly increased, and they increased with the increase of specific surface area. The bioaccessibility of polysaccharide and triterpene from unbroken GLSP after the intestinal stage were 29.52% and 5.37%, respectively. The bioaccessibility of polysaccharides and triterpene from broken GLSP by MM‐R after the intestinal phase were 39.73–72.45% and 16.44–24.97%, while those by UFG‐L were 44.53–104.18% and 12.96–32.90%, respectively. CONCLUSION: The active ingredients of broken GLSP showed better digestion and absorption abilities than unbroken GLSP. Moreover, the specific surface area of GLSP by UFG‐L was lower than that by MM‐R, and the bioaccessibility of GLSP by UFG‐L was higher than that by MM‐R. © 2024 Society of Chemical Industry. [ABSTRACT FROM AUTHOR]

Recent advances in metadevices, featuring complex subwavelength metastructures, have dramatically transformed the control and manipulation of electromagnetic waves. However, the inherently narrow operational bandwidth of these devices, stemming from their wavelength‐specific meta‐atoms, restricts their application in rapidly advancing fields such as the Internet of Things and advanced intelligent systems. Here, a novel hyperband synergistic metadevice is introduced, realized through a comprehensive multi‐scale meta‐atom architecture. The complementary metal‐oxide‐semiconductor (CMOS)‐compatible prototype integrates the distinct properties of double‐walled carbon nanotubes with advanced interlayer and intralayer coupling mechanisms, coherently combining nanoscale, microscale, and macroscale meta‐atoms. This prototype is thus adept at operating across a wide electromagnetic spectrum, spanning from the centimeter‐wavelength microwave band to the hundred nanometer‐wavelength visible and infrared optical band. Significantly, this singular device synergistically delivers three critical functionalities: selective microwave absorption, efficient terahertz beam steering, and enhanced optical transparency. These result signifies a breakthrough in hyperband electromagnetic device engineering, leading to compact, versatile, intelligent electromagnetic platforms. [ABSTRACT FROM AUTHOR]

Double-walled carbon nanotube-yttria-stabilized ZrO2 nanocomposites are prepared by a mixing route followed by Spark Plasma Sintering. The double-walled carbon nanotubes (DWCNTs) have been previously subjected to a covalent functionalization. The nanocomposites present a high densification and show a homogenous dispersion of DWCNTs into a matrix about 100 nm in size. The DWCNTs are well distributed at the matrix grain boundaries but form larger bundles upon the increase in carbon content. The Vickers microhardness of the nanocomposites decreases regularly upon the increase in carbon content. Incorporation of carbon at contents higher than 2 wt.% results in significantly lower friction coefficients, both against alumina and steel balls, possibly because of the elastic deformation of the DWCNTs at the surface of the sample. Their presence also favors a reduction of the steel/ceramic contacts and reduces the wear of the steel ball at high loads. DWCNTs improve wear resistance and reduce friction without incurring any severe damage, contrary to multi-walled carbon nanotubes. [ABSTRACT FROM AUTHOR]

This research studies two systems composed by the Timoshenko beam model for double‐wall carbon nanotubes, coupled with the heat equation governed by Fourier's law. For the first system, the coupling is given by the rotation speed of the vertical filament in the beam βψt$$ \beta {\psi}_t $$ from the first beam of Timoshenko and the Laplacian of temperature δθxx$$ \delta {\theta}_{xx} $$, where we also consider the damping terms fractionals γ1(−∂xx)τ1ϕt$$ {\gamma}_1{\left(-{\partial}_{xx}\right)}^{\tau_1}{\phi}_t $$, γ2(−∂xx)τ2yt$$ {\gamma}_2{\left(-{\partial}_{xx}\right)}^{\tau_2}{y}_t $$, and γ3(−∂xx)τ3zt$$ {\gamma}_3{\left(-{\partial}_{xx}\right)}^{\tau_3}{z}_t $$, where (τ1,τ2,τ3)∈[0,1]3$$ \left({\tau}_1,{\tau}_2,{\tau}_3\right)\in {\left[0,1\right]}^3 $$. For this first system, we proved that the semigroup S1(t)$$ {S}_1(t) $$ associated to system decays exponentially for all (τ1,τ2,τ3)∈[0,1]3$$ \left({\tau}_1,{\tau}_2,{\tau}_3\right)\in {\left[0,1\right]}^3 $$. The second system also has three fractional dampings γ1(−∂xx)β1ϕt$$ {\gamma}_1{\left(-{\partial}_{xx}\right)}^{\beta_1}{\phi}_t $$, γ2(−∂xx)β2yt$$ {\gamma}_2{\left(-{\partial}_{xx}\right)}^{\beta_2}{y}_t $$, and γ3(−∂xx)β3zt$$ {\gamma}_3{\left(-{\partial}_{xx}\right)}^{\beta_3}{z}_t $$, with (β1,β2,β3)∈[0,1]3$$ \left({\beta}_1,{\beta}_2,{\beta}_3\right)\in {\left[0,1\right]}^3 $$. Furthermore, the couplings between the heat equation and the Timoshenko beams of the double wall carbon nanotubes for the second system are given by the Laplacian of the rotation speed of the vertical filament in the beam βψxxt$$ \beta {\psi}_{xxt} $$ of the first beam of Timoshenko and the Lapacian of temperature δθxx$$ \delta {\theta}_{xx} $$. For the second system, we prove the exponential decay of the associated semigroup S2(t)$$ {S}_2(t) $$ for (β1,β2,β3)∈[0,1]3$$ \left({\beta}_1,{\beta}_2,{\beta}_3\right)\in {\left[0,1\right]}^3 $$ and also show that this semigroup admits Gevrey classes s>(ϕ+1)/(2ϕ)$$ s>\left(\phi +1\right)/\left(2\phi \right) $$ for ϕ=min{β1,β2,β3},∀(β1,β2,β3)∈(0,1)3$$ \phi =\min \left\{{\beta}_1,{\beta}_2,{\beta}_3\right\},\forall \left({\beta}_1,{\beta}_2,{\beta}_3\right)\in {\left(0,1\right)}^3 $$, and we finish our investigation proving that S2(t)$$ {S}_2(t) $$ is analytic when the parameters (β1,β2,β3)∈[1/2,1]3$$ \left({\beta}_1,{\beta}_2,{\beta}_3\right)\in {\left[1/2,1\right]}^3 $$. [ABSTRACT FROM AUTHOR]

Numerous studies have been conducted to examine the vibroacoustic characteristics of lightweight double-walled structures due to the anticipated applications of these structures in noise reduction engineering. In this study, third-order shear deformation theory (TSDT) is used to develop a theoretical model that predicts sound transmission loss (STL) across double-walled electro-rheological fluid (ERF) sandwich plates with functionally graded carbon nanotube reinforced composite (FG-CNTRC) facesheets. The extended rule of mixture is utilized to evaluate the properties of the FG-CNTRC material in the thickness. Depending on the four FG models, the CNT volume fraction varies. A sufficient displacement continuity condition is taken into account between layers. Furthermore, it should be noted that changing the electric field affects the pre-yield zone's ERF features. The vibroacoustic equations are derived using Hamilton's principle and solved utilizing weighted residual (Galerkin) technique considering simply supported and clamped boundary conditions. Several studies are done to compare the results of the suggested model with other results found in the literature. An extensive numerical study is conducted to examine the dependence of STL on several parameters, including electric field strength, volume percentage of the CNTs, CNTs distribution, depth of acoustic cavity. [ABSTRACT FROM AUTHOR]

Aspects of solid‐state processing of nascent disentangled ultra‐high‐molecular‐weight polyethylene (UHMWPE) powders of different syntheses mixed with electrically conductive carbon nanoparticles (NPs) of various types are studied. Effect of multiple parameters of the processing procedures on the electrophysical characteristics of the composite samples is investigated. Such parameters include time of preliminary ultrasonication (US) of NPs, time of US of UHMWPE/NPs mixtures, molding time, temperature, and pressure, deformation degree, etc. It is observed that by selecting optimal values of such parameters it is possible to obtain samples of composites with an extremely segregated structure made of the NPs, with NPs distributed evenly on the surfaces of the compacted UHMWPE powder particles. This ensures high levels of conductivity at very low values of NPs content. The segregated structure is retained when the composites are strengthened using the solid‐state uniaxial shear deformation process. While conductivity of most of the composites filled with various types of NPs monotonously decreases with the deformation ratio, conductivity of the composites filled with exceptionally long double‐walled carbon nanotubes is maintained. The processed oriented composites are also characterized by high EMR shielding properties, as well as interesting temperature dependencies of the electrical conductivity. [ABSTRACT FROM AUTHOR]

AbstractThis study aims to investigate the crashworthiness performance of a novel hierarchical multi-cell double circular tubes (HMDC) structure under axial impact. Various dual-tube structures of different cross-sections were designed. The effects of hierarchical order, peak number of the core column, and inner circle diameter on the structure were analyzed using Abaqus finite element analysis. The results indicate that in dual-tube structures, replacing the traditional multi-cell structure with a hierarchical multi-cell structure in the interlayer significantly improves energy absorption (EA) characteristics. With the inner circle diameter of the HMDC fixed at 20 mm, the ratio of mean crushing force (MCF) to peak crushing force at the third order increased by 70.70% and 35.68% compared to the first and second orders, respectively. Experimental results and finite element results show that the initial peak value differed by 1.47%, indicating a close match between the experimental and simulation results. The parametric study shows that the inner circle diameter and the peak number of the core column significantly affect EA. The findings of this study provide effective guidance for designing multi-cell dual circular tubes with high EA efficiency. [ABSTRACT FROM AUTHOR]

In this study, the thermal behaviour of small-sized single-atom CNTs was examined. CNTs are composed of crystals that form a nanostructure with different geometric shapes by arranging them in different ways according to the length-diameter ratio. Due to the mechanical, electrical, and thermal properties of CNTs, the thermal conduction of CNT materials is critical in controlling the performance and stability of CNTs. CNTs, which are low-dimensional materials with a single atomic layer thickness, have excellent thermal conductivity. According to the simulation technique in ANSYS, CNTs containing the same number of atoms and bonds were developed. The heat transfer of different structures of CNTs in armchairs (6,6) and zig-zag (12,0) were compared. A comparison of zig-zag and armchair CNTs thermal behaviour shows that zig-zag CNTs lattice structure has more advantages than armchair CNTs lattice structure by heat transfer. In this study, finite element-based thermal analysis of single and double-walled armchair and zig-zag carbon nano-tubes (CNTs) using the lattice method was investigated. A simulation technique was developed and applied in the ANSYS program for single and double-walled carbon nanotubes (CNTs). Armchairs (6,6) and zig-zag (12,0) CNTs in different lattice structures with equal atomic numbers and bond numbers are modelled according to different diameters and length ratios. The CNTs, which have the same material properties as the trays placed at both open ends of the pipes, are kept at different temperature values, and conduction heat transfer behaviour is investigated for certain temperature values. According to the investigated heat conduction behaviour of zig-zag and armchair CNTs, the lattice structure of the zig-zag carbon nano-tubes is more advantageous in terms of heat conduction than the cage structure of armchair CNTs, and it transmits heat faster than the armchair CNTs. [ABSTRACT FROM AUTHOR]

Wearable smart sensors have broad prospects in medical health and physical exercise. In this study, the core–shell conductive fiber membrane was prepared by adding multiwalled carbon nanotubes during polymerization of aniline on spun fibers. In comparison to the conventionally utilized polymerized aniline, the integration of carbon nanotube particulates enhances the conductivity and surface area, provides more aniline polymerization sites, and simultaneously increases the stability of the composite film. The pressure sensor has a sensitivity of 61.12, 40.32, and 23.17 kPa−1 in the range of 0–7.1 kPa, 7.1–11.1 kPa, and 11.1–19.54 kPa. In addition, it has a fast response time (loading time of 120 ms and unloading time of only 22 ms) and exhibits excellent cyclic stability through numerous loading–unloading cycles. These properties enable the sensor to be applied to real‐time monitoring of human sports health, such as knee and elbow bending, mouse clicking, beaker holding, and so on. This research method provides a new strategy and technology for conducting polymers as materials for flexible electronic equipment. [ABSTRACT FROM AUTHOR]

It is inevitable that carbon nanotubes (CNTs) are subjected to random vibrations due to environmental noise, which may impair their mechanical properties. The nonlinear dynamics associated with single-walled carbon nanotubes (SWCNTs) under random noise has been investigated in this work. First, based on the nonlocal theory and the Euler–Bernoulli beam model with fixed supports at both ends, the governed equations and boundary conditions are established according to Hamilton’s principle. Second, the Galerkin method is used to approximate the differential equations of motion and the stochastic averaging method (SAM) is applied to predict the approximate response of the original system. Subsequently, a detailed parametric study is conducted to analyze the nonlinear random vibration response of the SWCNT with nonlocal effects, and the effectiveness of the proposed method is verified by comparing the analytical results with those from the Runge–Kutta method. Finally, by solving the backward Kolmogorov (BK) equation and the generalized Pontryagin (GP) equation simultaneously, the conditional reliability function (CRF) and mean first-passage time (MFPT) for determining the reliability of SWCNT systems are obtained. [ABSTRACT FROM AUTHOR]

The multi-cell tube has been widely studied and applied in vehicle collision energy absorption due to its superior energy absorption capacity compared to traditional single tubes. The origami thin-walled structure is at the forefront of research on automotive energy absorption structures, thanks to its advantages such as low initial peak force, high energy absorption efficiency, and predictable deformation. In this study, a group of biologically inspired multi-cell tubes with origami-type outer walls was designed, and three design variables including the thickness of the outer wall, the ratio of outer to inner wall thickness, and the peak value ratio of the sine wave period were optimized. The design of experiment (DOE) was used to select the sample points needed to construct the surrogate model, and then a response surface model was built based on the criteria of minimum initial peak force (PCF) and maximum specific energy absorption (SEA). Finally, the non-dominated sorting genetic algorithm (NSGA-II) was used to optimize the design variables, resulting in a series of optimal solutions. The improved algorithm was used to select the best solution according to the requirements, and the optimization results were verified for their accuracy and reliability through simulation experiments. The results show that changing the values of the three design variables of the thin-walled tube will significantly affect the initial peak force and specific energy absorption. The optimal values after optimization were found to be 109.063 KN for PCF and 25.786 J/g for SEA. [ABSTRACT FROM AUTHOR]

The specific objective of this study is to analyze the dynamics of functionally graded carbon nanotubes (FGCNT) reinforced double plates. Connected via an elastic layer, the plates have simply supported boundary conditions. In the current study, three carbon nanotubes functionally graded patterns, varying in the thickness direction are considered, including uniformly distributed, functionally graded O-pattern, and functionally graded X-pattern. Following the development of the coupled equations of motion using the Hamilton principle while considering the influences of the elastic layer, the equations are subsequently solved utilizing a two-spatial-variable modal decomposition method. For verification purposes, the equations developed are compared to simplified configurations provided in the existing studies. The solution methodology is verified through comparing against numerical results of simplified configurations of plates obtained from the development of the finite element method and existing studies. Both verifications have shown very good agreement. Influences of plates' dimensions, carbon nanotubes reinforcement, and the stiffness of elastic layer are analyzed and provided in this study. The transverse-motion natural frequencies of the double plates are also identified, and they follow a decreasing trend as the aspect ratio increases for all the cases. The fundamental lateral-motion and axial-motion natural frequency also follows a similar trend as the aspect ratio increases. The reinforcement effect of carbon nanotubes on the transverse-motion natural frequencies is less obvious for thinner plates. An increase in the elastic layer stiffness increases the second series transverse-motion natural frequencies of the double-plate system. Among the considered functionally graded patterns, the functionally graded X-pattern reinforcement provides the largest increase in the transverse-motion natural frequencies. [ABSTRACT FROM AUTHOR]

An atomic-continuum coupling (ACC) method is developed for the nonlinear mechanical analysis of defective double-walled carbon nanotubes (DWCNTs). The moving least squares (MLS) approximation is resorted to bridge the fully atomic discrete structures of defective DWCNTs and the corresponding virtual continuum solids. The intrinsic mechanic laws implied in nanostructures can be accurately mapped into the mechanical governing equations of the continuum models. Based on ACC method, a numerical computational scheme is developed for predicting the buckling and contact behaviors of defective DWCNTs, which do not need any numerical integration method to calculate potential functional and its derivatives. The numerical tests show that this method can furnish good predictions even with a small number of nodes. It is found that Stone–Wales (SW) defects can lead to greatly decrease in the buckling properties of DWCNTs. In contrary, the complex interlayer van der Waals (vdW) interactions can enhance the buckling resistance of DWCNTs. [ABSTRACT FROM AUTHOR]

The unique mechanical, optical, and electrical properties of carbyne, a one-dimensional allotrope of carbon, make it a highly promising material for various applications. It has been demonstrated that carbon nanotubes (CNTs) can serve as an ideal host for the formation of confined carbyne (CC), with the yield being influenced by the quality of the carbon nanotubes for confinement and the carbon source for carbyne growth. In this study, a robust synthesis route of CC within CNTs is proposed. C70 was utilized as a precursor to provide an additional carbon source, based on its ability to supply more carbon atoms than C60 at the same filling ratio. Multi-step transformation processes, including defect creation, were designed to enhance the yield of CC. As a result, the yield of CC was significantly increased for the C70 encapsulated single-walled CNTs by more than an order of magnitude than the empty counterparts, which also surpasses that of the double-walled CNTs, making it the most effective route for synthesizing CC. These findings highlight the importance of the additional carbon source and the optimal pathway for CC formation, offering valuable insights for the application of materials with high yield. [ABSTRACT FROM AUTHOR]

Because of their large surface areas, nanotubes and nanowires demonstrate exquisite mechanical coupling to their surroundings, promising advanced sensors and nanomechanical devices. However, this environmental sensitivity has resulted in several ambiguous observations of vibrational coupling across various experiments. Herein, we demonstrate a temperature-dependent Radial Breathing Mode (RBM) frequency in free-standing, electron-diffraction-assigned Double-Walled Carbon Nanotubes (DWNTs) that shows an unexpected and thermally reversible frequency downshift of 10 to 15%, for systems isolated in vacuum. An analysis based on a harmonic oscillator model assigns the distinctive frequency cusp, produced over 93 scans of 3 distinct DWNTs, along with the hyperbolic trajectory, to a reversible increase in damping from graphitic ribbons on the exterior surface. Strain-dependent coupling from self-tensioned, suspended DWNTs maintains the ratio of spring-to-damping frequencies, producing a stable saturation of RBM in the low-tension limit. In contrast, when the interior of DWNTs is subjected to a water-filling process, the RBM thermal trajectory is altered to that of a Langmuir isobar and elliptical trajectories, allowing measurement of the enthalpy of confined fluid phase change. These mechanisms and quantitative theory provide new insights into the environmental coupling of nanomechanical systems and the implications for devices and nanofluidic conduits. Nanotubes exhibit high vibrational coupling to the environment but lack a theoretical description. Vacuum-isolated, suspended double walled nanotubes provide a damping model for mass coupling, offering new nanomechanics and nanofluidics insights. [ABSTRACT FROM AUTHOR]

E‐glass fibers are widely preferred due to ease of processing and its low cost, which has substantial scope in the fields of electronics and electrical insulation applications. Because of its low strength and corrosion resistance, use of E‐glass fibers is limited in aerospace and automotive applications. There is a need for enhancing the properties of the composite to overcome such limitations. Therefore, an attempt is made to introduce multi‐walled carbon nanotubes (MWCNT) as fillers into E‐glass fibers to meet the industry needs. In the current study, woven glass fiber of 5 layers and multi‐walled nano carbon fillers of 2, 4 and 6 by wt%, LY556 epoxy resin, and HY951 hardener were used to prepare 4 different type of composites along with the neat epoxy glass fiber reinforced polymer composites (GFRP). The hand‐layup route was used in the composite preparation due to its low cost, technological feasibility, and simple process setup. The developed samples were characterized for mechanical properties via tensile, flexural and impact tests. Tribological characteristics were performed by air jet erosion test. Chauvenet's criterion is applied for identifying the outliers (if any) from the data of repeated test properties. Taguchi's L9OA (orthogonal array) is selected for obtaining optimal hybrid composite, which yield better mechanical properties. Empirical relations are developed for the material properties in terms of process variables. The sample (4 wt% MWCNT) exhibited enhancement of 17.27% in tensile strength, 6% of impact strength and 7.3% of flexural strength when compared with neat epoxy GFRP. This hybrid composite is considered for thermal aging and observed at 60°C, 8% increase in tensile, 7% increase of impact and 15% in flexural strength due to the precipitation on carbon nano tubes along the gain boundaries. The present study recommends 4% MWCNT fillers in developing hybrid glass epoxy polymer composites for use in aerospace, automotive and civil construction industries due to economic and technological feasibility. Highlights: Utilize low‐cost E‐glass fibers in electronics and electrical insulation applications.Improve composite properties for aerospace and automotive industries.Develop hybrid glass epoxy composites with 2 to 6 wt% MWCNT fillers.Examine wear characteristics under air jet erosion and study the impact of thermal aging on mechanical properties.Apply Chauvenet's criterion for outlier identification in measured properties datasets. [ABSTRACT FROM AUTHOR]

The successful utilization of an eco‐friendly and biocompatible parylene‐C substrate for high‐performance solution‐processed double‐walled carbon nanotube (CNT) electrode‐based perovskite solar cells (PSCs) was demonstrated. Through the use of a novel inversion transfer technique, vertical separation of the binders from the CNTs was induced, rendering a stronger p‐doping effect and thereby a higher conductivity of the CNTs. The resulting foldable devices exhibited a power conversion efficiency of 18.11%, which is the highest reported among CNT transparent electrode‐based PSCs to date, and withstood more than 10,000 folding cycles at a radius of 0.5 mm, demonstrating unprecedented mechanical stability. Furthermore, solar modules were fabricated using entirely laser scribing processes to assess the potential of the solution‐processable nanocarbon electrode. Notably, this is the only one to be processed entirely by the laser scribing process and to be biocompatible as well as eco‐friendly among the previously reported nonindium tin oxide‐based perovskite solar modules. [ABSTRACT FROM AUTHOR]

Herein, we employed a developed linear response time dependent density functional theory-based nonadiabatic dynamics simulation method that explicitly takes into account the excitonic effects to investigate photoinduced excitation energy transfer dynamics of a double-walled carbon nanotube (CNT) model with different excitation energies. The E11 excitation of the outer CNT will generate a local excitation (LE) |out*〉 exciton due to its low energy, which does not induce any charge separation. In contrast, the E11 excitation of the inner CNT can generate four kinds of excitons with the LE exciton |in*〉 dominates. In the 500-fs dynamics simulation, the LE exciton |in*〉 and charge transfer (CT) excitons |out−in+〉 and |out+in−〉 are all gradually converted to the |out*〉 exciton, corresponding to a photoinduced excitation energy transfer, which is consistent with experimental studies. Finally, when the excitation energy is close to the E22 state of the outer CNT (∼1.05 eV), a mixed population of different excitons, with the |out*〉 exciton dominated, is generated. Then, photoinduced energy transfer from the outer to inner CNTs occurs in the first 50 fs, which is followed by an inner to outer excitation energy transfer that is completed in 400 fs. The present work not only sheds important light on the mechanistic details of wavelength-dependent excitation energy transfer of a double-walled CNT model but also demonstrates the roles and importance of CT excitons in photoinduced excitation energy transfer. It also emphasized that explicitly including the excitonic effects in electronic structure calculations and nonadiabatic dynamics simulations is significant for correct understanding/rational design of optoelectronic properties of periodically extended systems. [ABSTRACT FROM AUTHOR]

In situ transmission electron microscopy was used to observe the electromigration-driven sliding behavior of twinned face-centered cubic-Co fillers sliding inside multi-walled carbon nanotubes with an inner-diameter step. Each filler contained a twin boundary located at the nanotube inner-diameter step. Under application of an electric current, the twinned Co fillers moved across the steps and changed their diameter, and the position of the twin boundary was maintained at the nanotube inner-diameter step. [ABSTRACT FROM AUTHOR]

Bimetallic lined pipe (BLP) has been increasingly used in offshore and subsea oil and gas structures, but how to identify the invisible inner defects such as liner wall thinning and interface debonding is a challenge for future development. A nondestructive testing (NDT) method based on pulsed eddy current testing (PECT) has been proposed to face these difficulties. The inspection of the BLP specimen (AISI1020 base tube and SS304 liner) is implemented from outside of the pipe by using a transmitter–receiver-type PECT probe consisting of two induction coils. By simplifying the BLP specimen to stratified conductive plates, the electromagnetic field interaction between the PECT probe and specimen is analytically modeled, and the probe inspection signals due to liner wall thinning and interface debonding are calculated. In order to highlight the weak response (in microvolts) from the liner, the inspection signals are subtracted by the signal, which is calculated in the case of only having a base tube, yielding differential PECT signals. The peak voltage of the differential signal is selected to characterize the liner wall thinning and interface debonding due to its distinguishable and linear variation. Experiment verification is also carried out on a double-walled specimen simulated by a combination of a Q235 casing pipe and SS304 tubes of different sizes. The experimental results basically agree with the analytical predictions. The peak value of the PECT signal has an ascending and descending variation with the increase in the remaining liner wall thickness and debonding gap, respectively, while the negative peak value shows opposite changes. The peak value exhibits a larger sensitivity than the negative peak value. The proposed method shows potential promise in practical applications for the evaluation of the inner defects in BLP lines. [ABSTRACT FROM AUTHOR]

This manuscript uses molecular dynamics simulations to research the self-assembly process between heterocyclic compounds and carbon nanotubes. These results show that multiple polybenzothiazole chains self-curl into the interior of carbon nanotube to form a perfect helical structure. The main driving forces are van der Waals forces and π–π stacking interaction between polybenzothiazol chains and carbon nanotube. The impact of variables on final configuration of the composites, including polymer chains number, carbon nanotube diameter, polymer length, polybenzothiazole chain position and temperature, were also examined. Theoretical support for hybrid structure design and manufacturing in the realm of functional devices and advanced composites will be greatly enhanced by these results. [ABSTRACT FROM AUTHOR]

Strain engineering, as a powerful strategy to tune the optical and electrical properties of two-dimensional (2D) materials by deforming their crystal lattice, has attracted significant interest in recent years. 2D materials can sustain ultra-high strains, even up to 10%, due to the lack of dangling bonds on their surface, making them ideal brittle solids. This remarkable mechanical resilience, together with a strong strain-tunable band structure, endows 2D materials with a broad optical and electrical response upon strain. However, strain engineering based on 2D materials is restricted by their nanoscale and strain quantification troubles. In this study, we have modified a homebuilt three-points bending apparatus to transform it into a four-points bending apparatus that allows for the application of both compressive and tensile strains on 2D materials. This approach allows for the efficient and reproducible construction of a strain system and minimizes the buckling effect caused by the van der Waals interaction by adamantane encapsulation strategy. Our results demonstrate the feasibility of introducing compressive strain on 2D materials and the potential for tuning their optical and physical properties through this approach. [ABSTRACT FROM AUTHOR]

The paper concerns the dynamics and stability of double-walled carbon nanotubes conveying fluid. The equations of motion adopted in the current study to describe the dynamics of such nano-pipes stem from the classical Bernoulli–Euler beam theory. Several additional terms are included in the basic equations in order to take into account the influence of the conveyed fluid, the impact of the surrounding medium and the effect of the van der Waals interaction between the inner and outer single-walled carbon nanotubes constituting a double-walled one. In the present work, the flow-induced vibrations of the considered nano-pipes are studied for different values of the length of the pipe, its inner radius, the characteristics of the ambient medium and the velocity of the fluid flow, which is assumed to be constant. The critical fluid flow velocities are obtained at which such a cantilevered double-walled carbon nanotube embedded in an elastic medium loses stability. [ABSTRACT FROM AUTHOR]

A fractional technique is used to evaluate the temperature, mass, and velocity flow of single and double wall CNTs over a vertical plate. Slip boundary conditions and applied magnetic force are addressed. Human blood is used to examine how base fluid behaves. Applying the proper dimensionless variables results in the dimensionless formulation of initial and boundary conditions related to the governed dimensional concentration, momentum, and energy equations. The Laplace transform technique is used to resolve the dimensionless governing partial differential equations and get the solutions. The constant proportional Caputo (CPC) time-fractional derivative is a unique class of fractional model used in the simulation technique. The fundamental definitions are used to support the said model first. Using MWCNTs and SWCNTs in comparison to the flow characteristics, a thermal and mass study is given. The heat and mass transfer processes for single-walled carbon nanotubes (SWCNTs) have been shown to typically be progressive. The momentum profile decreases as the fractional variables rise. Multi-walled carbon nanotubes (MWCNTs) show more progressive velocity control as a result of the magnetic parameter. Graphs demonstrate the influence of embedding factors on the velocity, energy, and concentration profiles. [ABSTRACT FROM AUTHOR]

Active Distribution Networks are Multi-Input Multi-Output (MIMO) systems with coupled dynamics, which cause interactions among the control loops of Distributed Energy Resources (DERs). This undesired effect leads to performance degradation of voltage control. To mitigate the effects of this unavoidable coupling, the present paper proposes a systematic design procedure based on the analysis of the interaction's sources. In detail, each DER is equipped with a double-loop PI to control the active and reactive power output of the voltage source converter, which connects the DER to the network's node. Furthermore, to guarantee ancillary services, the two loops are coupled by a simple mechanism of cooperation of the active power to voltage regulation realized by a filtered droop law. To achieve voltage regulation with reduced loop interactions, the PI parameters and the filter's pulse are designed according to a procedure with two sequential steps based on the Internal Model Control (IMC) technique. Simulation studies are finally presented to demonstrate that the proposed design method achieves both reduction of the loop interaction and robust voltage control in the presence of model parameter uncertainty in the MIMO plant, modeling various operating conditions of the ADN, including a step connection of large loads, renewable energy source variations, and changes in the substation transformer ratio. [ABSTRACT FROM AUTHOR]

To investigate the self-healing performance of multi-walled carbon nanotube-modified asphalt and its influencing mechanism, the asphalt molecular self-healing models were established by the molecular dynamics method. The results were analyzed based on molecular diffusion theory and surface energy repair theory. Based on the Arrhenius model, two theories were combined, and a new index healing factor was proposed to evaluate the self-healing performance by considering the diffusion characteristics and energy changes of asphalt molecules. The results show that multi-walled carbon nanotubes can accelerate the diffusion behavior of molecules in the temperature of 278--318 K to improve the self-healing properties of asphalt. Based on the proposed surface free energy equation, the self-healing properties are reasonably evaluated; the enthalpy change can be used as an index for judging the self-healing performance. The transformation model of the diffusion coefficient and cohesive work and the new index can reflect the self-healing performance more comprehensively. [ABSTRACT FROM AUTHOR]

Purpose: This paper mainly studies the double Hopf bifurcation for coupled van der Pol–Rayleigh system with time delay. It aims to see how time delay and coupling factors affect the system, then avoid unstable or harmful vibrations and look for steady state in engineering. Methods: This paper mainly uses the normal form and center manifold theory and the Runge–Kutta method. First, we analyze the stability switching of the coupled van der Pol–Rayleigh system with time delay and the dynamical behavior caused by the double Hopf bifurcation. Secondly, we derive the normal form of double Hopf bifurcation by the normal form and center manifold theory. Then the dynamical phenomena of the system are investigated. Finally, we perform numerical simulations to verify the theoretical analysis by the Runge–Kutta method. Results: The stability switching region of the system with respect to the delay is obtained. And the parameter regions of amplitude death, stable periodic motion and quasi-periodic motion are obtained. And as parameter values change, the steady state of the periodic solution follows. Conclusions: In the field of engineering, it is more practical to consider systems with time delay. So we consider system with time delay, obtain the stability switching region about the time delay and discuss the dynamics of each bifurcation region. When doing some system design, it is necessary to avoid the occurrence of bifurcation behavior, because it will lead to changes in system stability. We can adjust the system parameters to avoid bifurcation according to stability region. Or some engineering problem requires the avoidance of harmful vibrations and the pursuit of steady state. With the change of time delay and coupling factors, we can find the amplitude death region and the region of stable periodic motion and quasi-periodic motion, thus avoiding harmful vibration in practical engineering by adjusting the parameters. [ABSTRACT FROM AUTHOR]

This research delves into the study of thermal vibration characteristics exhibited by three distinct types of Single‐Walled Carbon Nanotubes (SWCNTs): armchair, chiral, and zigzag configurations. The investigation is carried out using Navier's technique, which integrates a non‐local elasticity theory and Euler‐Bernoulli beam theory, providing a comprehensive understanding of carbon nanotubes (CNT) behavior under varying temperature conditions. To explore these characteristics, governing equations for vibrations are derived based on Hamilton's principle, incorporating both non‐local stress resultants. These equations are instrumental in computing the natural frequencies of Hinged‐Hinged (HH) SWCNTs subjected to low (room) and high‐temperature conditions. A detailed exploration is conducted to evaluate the influence of several key scaling parameters. These parameters encompass small‐scale effects, temperature variations, the thermal environment, and the length‑to‑thickness ratio of the CNTs, scrutinizing their impact on the first and second mode natural frequencies. This comprehensive assessment sheds light on the multifaceted interplay between these factors and the resulting vibration behaviors in SWCNTs. [ABSTRACT FROM AUTHOR]

In this study, the behavior of double-walled carbon nanotubes (DWCNTs) used as mass sensors is explored under various boundary conditions; particular attention is paid to the crucial topic of resonant nanomechanical mass sensors. In the presented approach, nanotubes are subjected to a distributed transverse magnetic force and supported by an elastic foundation. The impacts of the longitudinal magnetic field, elastic medium, and diverse physical parameters on the responsiveness of the sensors are assessed. Using the energy method, governing equations are formulated to determine the frequency shifts of the mass nanosensors. Our findings reveal significant variations in the frequency shifts due to a longitudinal magnetic field, which depends on the applied boundary conditions. This research holds significance in the design of resonant nanomechanical mass sensors and provides valuable insights into the interplay of factors affecting their performance. Through exploring the intricate dynamics of DWCNTs used as mass sensors and thus contributing to the broader understanding of nanoscale systems, the implications for advancements in sensor design are offered and applications are introduced. [ABSTRACT FROM AUTHOR]

In this paper, non-equilibrium molecular dynamics simulations are used to study the interfacial heat exchange capacity of one-dimensional carbon nanotube nested structures. When the radius of the CNT substrate is increased from 1.356 to 2.712 nm, the ITC has a great enhancement from 1.340 to 2.949 nw/k. After this, we investigate the effects of overlap length, CNT length, and van der Waals interaction strength on the thermal resistance of the interface between carbon nanotubes. Firstly, we found that the nesting depth can significantly increase the ITC, and the increase in ITC is more obvious at an overlap length of 40 Å than at 30 Å. After this, the effect of length on the interfacial thermal conductivity is investigated, and the interfacial thermal conductivity is enhanced by 33.8% when the length is increased to 30 nm. Finally, the effect of van der Waals interaction strength was investigated, and the ITC increased from 1.60 nW/K to 2.71 nW/K when the scale factor was increased from 1 to 2. [ABSTRACT FROM AUTHOR]

In this study, a new anisotropic elastic shell model with a nonlocal strain gradient is developed to investigate the vibrations of simply supported single-walled carbon nanotubes (SWCNTs). The Sanders–Koiter shell theory is used to obtain strain–displacement relationships. Eringen's nonlocal elasticity and Mindlin's strain gradient theories are adopted to derive the constitutive equations, where the anisotropic elasticity constants are expressed via Chang's molecular mechanics model. An analytical method is used to solve the equations of motion and to obtain the natural frequencies of SWCNTs. First, the anisotropic elastic shell model without size effects is validated through comparison with the results of molecular dynamics simulations reported in the literature. Then, the effects of the nonlocal and material parameters on the natural frequencies of SWCNTs with different geometries and wavenumbers are analyzed. From the numerical simulations, it is confirmed that the natural frequencies decrease as the nonlocal parameter increases, while they increase as the material parameter increases. As new results, the reduction in natural frequencies with increasing SWCNT radius and the increase in natural frequencies with increasing wavenumber are both amplified as the material parameter increases, while they are both attenuated as the nonlocal parameter increases. [ABSTRACT FROM AUTHOR]

This work explores the feasibility of nonlinear behavior of doubly clamped single-walled boron nitride nanotube (SW-BNNT)-based nanoresonator. A nonlinear mathematical model of wavy SW-BNNT has been developed for analyzing the geometrical nonlinearity. Dynamic responses of nonlinear model have been analyzed for different waviness factors varying from 0.01 to 0.06 using various tools like time series, phase space, Poincaré map and Fast Fourier Transforms (FFTs). For the analysis, 20 nm length of SW-BNNT has been considered. It has been observed from nonlinear analysis, that for responses with a lower value of waviness (e.g., 0.01) for 20 nm long BNNT, the system's nature loses its periodicity and shows onset of chaos with dense spectrum in Poincaré maps and irregular pattern in time response. Thus, it is concluded that chaotic response with a less strange attractor has been observed when waviness is 0.01. It is also concluded that, with increase in waviness factor from 0.02 to 0.06, the system showed the multi-periodic response with 2-T, 3-T and 4-T periods. The dynamic responses with varying waviness showed that the system behavior is changing from chaotic to periodic. This change in periodicity is one of the characteristics of chaotic solution. [ABSTRACT FROM AUTHOR]

Attaining a high energy density that aligns with practical application requirements is a crucial indicator in the advancement of supercapacitors. In this paper, a hybrid hierarchical electrode structure of N-doped carbon nanotube (NCNT) spheres encapsulated with NiCo-Se nanoparticles (NPs) and coated with nickel–cobalt layered double hydroxide (NiCo-LDH) multilayer nanosheets was successfully synthesized on a nickel foam (NF) substrate. The self-supporting strategy enables nickel–cobalt Prussian blue analogues (Ni–Co PBAs) to be directly attached to the NF surface, which results in fluffy NCNTs with a high length–diameter ratio and considerable yield and greatly enhances the conductivity of the electrode material. The synergistic interaction between the dual transition metal compounds inside and outside the NCNTs enables the hybrid electrode material to achieve an impressive specific capacity of 1899 F g−1 (211.0 mA h g−1) at 1 A g−1. The asymmetric supercapacitor (ASC) exhibits an excellent energy density of 57.6 W h kg−1 at a power density of 798 W kg−1. This study not only provides an attractive strategy for obtaining CNTs with excellent properties from Ni–Co PBA and synthesizing hybrid electrodes with efficient synergistic effects, but also achieves a high energy density that aligns with the practical application demands of supercapacitors. [ABSTRACT FROM AUTHOR]

Based on a mutual internal relationship among membrane properties (e.g., permeability, selectivity, antifouling ability), a comprehensive performance improvement of the thin film composite (TFC) membrane remains the huge issue. In this study, single walled carbon nanotube (SWCNT) was used as a nanofiller to tune the polyester membrane via the IP reaction with carboxymethyl cellulose (CMC) and TMC as aqueous and organic monomer, respectively. Through Van der Waals interaction and hydrogen bonding with SWCNT, the diffusion behavior of CMC towards the TMC boundary was affected and finally tune the properties and structures of the polyester active layer. Besides, physical and chemical natures of the fabricated membranes modified by different SWCNT concentrations were characterized. The results revealed that polyester selective layer presented a rougher and more hydrophilic surface with an increased content, which were beneficial for water molecules transit. Consequently, the optimal TFC membrane decorated by 0.50 mg SWCNT presented an excellent permeance at 14.47 L m−2 h−1 bar−1 and satisfied dye retention of 99.7%, 100.0%, 100.0%, and 98.0% for congo red, coomassie blue G250, reactive blue 19, and methyl blue, respectively. Moreover, TFC membrane exhibited moderate salt rejections against Na2SO4 (91.8%), MgSO4 (23.2%), NaCl (24.3%), and MgCl2 (2.9%) and preferable long-term filtration stability of 72 h, which was rather competitive for the application of wastewater treatment. [ABSTRACT FROM AUTHOR]

Stimulated by the recent synthesis of penta-NiN 2 sheet [ ACS Nano 2021 , 15 , 13,539], we study the hydrogen adsorption on the sheet and the derived nanotubes by using density functional theory with the correction of van der Waals interactions. We have found that each Ni site can only adsorb two hydrogen molecules as expected from the 18-electron rule, the corresponding capacity is 4.44 wt%. As more H 2 molecules are introduced, H 2 can only be very weakly adsorbed on N sites. When the sheet is curved into nanotubes, the Ni–N distance is enlarged due to the stress, which weakens the orbital hybridizations between Ni and N, and reduces the charge transfer from Ni to N. The Ni ion with a less charge on the tube shows weak polarizing ability for H 2 molecule. • Penta-sheet and nanotube for hydrogen storage. • Each Ni site in the penta-NiN 2 sheet can only adsorb two H 2 molecules. • The perfect penta-NiN 2 sheet can't reach the DOE target for H 2 storage. • N-vacancy, Ni replacement, and grain boundary need to be introduced to enhance the adsorption energy and capacity. [ABSTRACT FROM AUTHOR]

The capacity for nanopatterning and functionality is a promising facet of supramolecular self‐assembly. However, the formation of molecular frameworks entirely dependent on van der Waals (vdW) interactions is infrequently explored. Herein, 2D vdW supramolecular structures are synthesized through the self‐assembled cocrystallization of C60 and decanethiol (DT) molecules on Au(111) surface. Notably, the system eliminates the need of functional groups for specific bonding between adjacent units. The conformation C60/DT is delicately manipulated by adjusting molecular coverage and annealing temperature. The absence of directional bonding between C60 and DT molecules facilitates the formation of a variety of stable phases at room temperature (RT), such as 1) porous C60 networks with thiol‐filled pores and 2) self‐synthesized (C60)n nanochains with thiol spacers interspersed between the chains are achieved and visualized by scanning tunneling microscopic imaging under RT. This innovative integration of the vdW interaction unveils new avenues for developing supramolecular patterns characterized by their comparatively weak but exceptionally adaptable bonding. [ABSTRACT FROM AUTHOR]

Four commercial multiwalled carbon nanotubes with distinct lengths and diameters were subject to planetary ball milling to induce length reduction. The Burgio-Rojac energy model was employed to calculate the single impact energy and cumulative energy dissipated to the carbon nanotubes during milling. The ratio of sample mass to bead mass and the nanotube bulk density did not affect length reduction during grinding. The minimum impact energy barrier for carbon nanotube length reduction appeared directly proportional to nanotube diameter for parallel wall morphologies, although a nanotube sample with a cup-stacked wall morphology showed a much lower energy barrier. A normalized exponential equation relating carbon nanotube length and cumulative impact energy collapsed all data to a single exponential master curve described by the same scaling parameters, namely a pre-exponential term that includes the initial nanotube length and a scaling energy in the exponent. [ABSTRACT FROM AUTHOR]

This study couples peridynamic (PD) theory with strain gradient elasticity (SGE) theory to investigate the combined effect of PD and SGE length scale parameters on size effect. The SGE theory introduces a length scale parameter in the stress–strain relations to account for size effect. The solution to the classical form of SGE equation of motion requires two additional non-classical boundary conditions arising from the presence of fourth-order spatial derivatives. The wave dispersions level off as the wave number increases as observed in real materials. The PD theory allows for nonlocal interactions of a material point within its horizon which serves as the PD length scale parameter. The equation of motion emerges in the form of an integral equation and the internal forces are expressed through nonlocal interactions (bonds) between the material points within a continuous body. It is a reformulation of classical continuum mechanics which is free of spatial derivatives. The numerical results concern a previously considered carbon nanotube (CNT). Under quasi-static axial loading, the results indicate an increased strengthening effect along the length of the tube. Under dynamic loading, its longitudinal vibration response is captured through explicit time integration. The numerical predictions capture the reference solutions corresponding to the classical SGE equation. [ABSTRACT FROM AUTHOR]

This research analyzes the influence of temperature changes on the vibration of single-walled carbon nanotubes (SW-CNTs) composite joined conical-cylindrical shells. The governing dynamic equations of temperature-dependent CNTs with initial thermomechanical stresses are established using the Love shell assumptions and classical shell theory. The initial thermomechanical stresses are derived from the linear membrane approach method. Two possibilities are assumed for the calculation of temperature change: a uniform temperature distribution and steady-state heat transfer by conduction through the thickness of the shell. The initial thermomechanical stresses are determined using the linear membrane approach. The generalized differential quadrature (GDQ) method is used to solve the equations after combining it with continuity conditions between the conical part and the cylindrical part and various boundary conditions. After validating the natural frequency and the different types of temperature distribution with the studies of other researchers, the effects of semi vortex of the cone, the volume fraction, and the type of distribution on the temperature rise are given as the results. The type of temperature distribution has the greatest influence among the parameters. [ABSTRACT FROM AUTHOR]

This article presents a literature review of the iron oxide nanoparticles synthesis routes with applications as nanocatalysts in the synthesis of carbon nanostructures using the plastic pyrolysis method. Through pyrolysis, it is possible to synthesize structures such as single-walled carbon nanotubes (SWCNTs), double-walled carbon nanotubes (DWCNTs), multi-walled carbon nanotubes (MWCNTs), and carbon nanofibers (CNFs). The morphological and chemical properties of the nanocatalysts ensure the majority production with minimal defects of these nanostructures. Regarding the iron oxide nanocatalyst, this review emphasizes the importance of parameters such as its shape and size, properties that are controlled during the synthesis process, and the significance of the interaction between nanoparticles and the support material used. These factors directly influence the nanocatalyst's performance in terms of catalytic activity, selectivity, and durability. [ABSTRACT FROM AUTHOR]

Purpose: This paper reported the modeling steps of coupled beam nanocomposite system and its fundamental frequency characteristics. The model has been derived for two straight coupled beams (made of carbon nanotube, CNT) as the continuous transitional springs, including a middle elastic layer. Methods: The effective properties of the beam components are evaluated based on the well-known rule of mixture. Additionally, to achieve the generality of the material distribution, various configurations of CNT have been adopted in the current model through the thickness of the structure. The main objective of the present study is to evaluate the effect of material temperature dependency on the frequency parameter of the nanocomposite double beam system. The structural model has been derived mathematically using the robust lower-order theory (first-order shear deformation, FSDT) to compute the eigenvalues without hampering the degree of solution accuracies. The nanotube properties are also considered to be temperature-dependent (TD). The final eigenvalues are computed via a semi-analytical approach, namely generalized differential quadrature (GDQ) approach. Results: First, the natural frequencies of homogenous beam system are compared with the results of frequency parameter available in the literature. Then, the fundamental frequencies of the coupled beam system have been computed analytically for different structural input parameters (material properties, end constraints of full structure and middle elastic layer) to showcase the effect individual and/or combined conditions with and without the influence of temperature. Conclusion: The final outcomes are revealed in detail for different input parameters and the subsequent outcomes. [ABSTRACT FROM AUTHOR]

Moreover, they illustrate the wide range of available tools, including crystal structure prediction (CSP) methods,[[11]] high-throughput calculations,[[13]] and machine learning (ML),[[15], [17]] and the role that databases, such as AFLOW,[19] Materials Project,[20] the Open Quantum Materials Database,[21] the Computational Materials Repository,[22] and the International Crystallographic Structure Database,[23] among many others, play in materials discovery. Tremendous advances in first-principles program packages, spectacular speed-ups in computer hardware coupled with significant algorithmic developments in crystal structure prediction, high-throughput screenings, data-mining, machine learning (ML), and artificial intelligence have made the dream of computational materials discovery a reality.[1] Recent success stories of materials that were first predicted and later verified experimentally include high-temperature superconductors,[[2], [4]] high-entropy high-hardness materials,[5] Heusler intermetallics for thermoelectrics and spintronics,[6] organic light-emitting diodes,[7] Li battery cathode materials,[8] porous materials for gas storage,[9] and carbon-boron clathrates.[10] The broad range of materials-by-design success stories with applications, including energy, quantum, structural, 2D materials, molecular crystals, molecular organic frameworks, and so on, have inspired us to devote this issue of JCP toward recent advances in this field. Parsaeifard I et al. i present a method to calculate fingerprint vectors from fingerprint distances, which measure the similarity of two structures.[27] This method is shown to automatically detect grain boundaries and the edges of carbon flakes without human input. [Extracted from the article]

Combining strong light absorption and outstanding electrical conductivity, hybrid nanographene–graphene (NG–Gr) van der Waals heterostructures (vdWHs) represent an emerging material platform for versatile optoelectronic devices. Interfacial charge transfer (CT), a fundamental process whose full control remains limited, plays a paramount role in determining the final device performance. Here, we demonstrate that the interlayer vdW interactions can be engineered by tuning the sizes of bottom-up synthesized NGs to control the interfacial electronic coupling strength and, thus, the CT process in NG–Gr vdWHs. By increasing the dimensions of NGs from 42 to 96 sp2 carbon atoms in the polyaromatic core to enhance the interfacial coupling strength, we find that the CT efficiency and rate in NG–Gr vdWHs display a drastic increase of one order of magnitude, despite the fact that the interfacial energy driving the CT process is unfavorably reduced. Our results shed light on the CT mechanism and provide an effective knob to tune the electronic coupling at NG–Gr interfaces by controlling the size-dependent vdW interactions. [ABSTRACT FROM AUTHOR]

The use of polymer-modified binders in asphalt concrete makes it possible to increase the efficiency and durability of highways. However, at present, there is an important and unresolved problem in this area, making it impossible to fully exploit the potential of modified binders. This is a tendency of aging processes that leads to the premature destruction of the pavement. In many literary sources, it is reported that reasons are related to the peculiarity of the chemical composition and occur at the submicron level. Therefore, the influence of single-walled carbon nanotubes has been studied for a better understanding of aging processes. The aging processes of the RTFOT (rolling thin film oven test) and PAV (pressure aging vessel) modified with SBS (styrene–butadiene–styrene) polymer, single-walled carbon nanotubes, and waste industrial oil were simulated in a laboratory furnace. Microstructural features were studied using the method of infrared spectral analysis. The dependences of viscoelastic properties on the component composition of binders were investigated. The optimal content of single-walled carbon nanotubes (0.001%), SBS (styrene–butadiene–styrene) polymer (3.5%), and waste industrial oil (4%) in the binder composition was established, which synergistically improved the performance of the modified binder from PG (52-22) (performance grade) to PG (64-34). It was established that single-walled carbon nanotubes provide improvement in the durability parameter ∆Tc binder by 150%, improved relaxation properties at low temperatures, and resistance to fatigue damage. [ABSTRACT FROM AUTHOR]

In this study, La2YBiO6 double perovskites were prepared using a sol–gel method and La2YBiO6 double perovskites decorated on multiwalled carbon nanotubes (LYB/MWCNTs) were prepared using a sonication method. LYB/MWCNTs displayed strong conductivity, electrocatalytic activity, and fast electron transfer. These features are essential for the simultaneous detection of nitrofurantoin (NFT) and ascorbic acid (AA) in biological samples. Various structural and morphological characterization approaches were used to validate the development of LYB/MWCNTs. LYB/MWCNTs/GCE were analysed using electrochemical techniques. Interestingly, LYB/MWCNTs displayed the lowest detection limit for NFT of 13.74 and AA of 12.37 nM with a linear concentration range of 10–120 nM (NFT and AA) whereas the individually estimated LOD for NFT and AA (10–120 nM) was 10.94 nM and 13.43 nM, respectively. The developed sensor demonstrates significant selectivity and its practicability for the detection of NFT and AA in food samples was investigated with good recoveries. [ABSTRACT FROM AUTHOR]

Honeycomb structures are widely used in the field of impact resistance and are constantly being developed and updated. In this paper, the design of three new aluminum alloy rotating thin-walled structures (NRTS) are examined. These structures combine common concave structures and rotating, rigid-body structures. The purpose of this study is to solve the problem of the poor energy absorption capacity of rotating, rigid-body structure due to small deformation and to provide a reference for honeycomb mechanism designs. The Young's modulus, the critical velocity, and the platform stress of the NRTS structure are derived from theoretical analysis. The dynamic response of the NRTS structure at different impact velocities is investigated using finite element simulation software. The results show that the rotating, thin-walled recessed honeycomb (RTRH) increases the plateau stress by 124% and 51% as compared to rotating, thin-walled square tubes (RTSTs) and the re-entrant hexagonal structure (RH), respectively; the rotating, thin-walled quadruple-arc honeycomb structure (RTQH) increases the SEA by 21% and 20% as compared to the RTST and RH, respectively; and the rotating thin-walled double-arc honeycomb structure (RTDH) increases the CEF by 54% and 51% as compared to the RTST and RH, respectively. During the study, it was demonstrated that NTRS also exhibits good energy absorption capacity. Then, the effect of rotation angle on the energy absorption performance was analyzed. The cell and wall thickness of the NTRS structure were optimized according to the gradient theory. It was proved that the gradient optimized structure has better energy absorption performance as compared to the uniform structure. [ABSTRACT FROM AUTHOR]