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Flexoelectric effect is strengthened in dielectrics at nanoscale so that it could not be neglected. In this work, a laminated composite plate with flexoelectric core and two coverings of CNTRCs is modeled. The variational principles of the plate with generalized supporting conditions are derived considering both the flexoelectricity of the piezoelectric core and the reinforcement of the CNTRCs. According to it, the governing equation and boundary conditions with any supporting types are obtained. Then the analytical solutions to the displacements and resonant frequencies of the plate with two different boundary conditions for free vibration are given. The numerical results prove that the flexoelectric effect relies on the scale seriously. Moreover, the CNTRCs coverings can improve the bending stiffness of the whole plate. Therefore, the bending responses such as resonant frequency and bending deflection can be adjusted and optimized by changing the ratio of the CNTs to the matrix. It’s hopeful to provide the theoretical basis of numerical calculation of electronic devices with laminated structures at nanoscale.

In this work, a rectangular cellular microplate is taken into consideration which is embedded between two functionally graded carbon nanotube-reinforced composite layers that have the piezoelectric ability. Different patterns for the carbon nanotube dispersion are considered. Moreover, an external electrical voltage is applied to them. The displacements are described based on a higher-order shear deformation theory which is called hyperbolic theory and the size influence is captured via the modified couple stress formulations. The governing motion equations are then derived using the variational technique and Hamilton’s principle. Then, for simply supported edge conditions, a closed-form solution is provided. Next, it turns to validate the results in simpler states, and after that, the effect of the most prominent parameters on the results is investigated. It is observed that by increasing the external applied voltage to the face sheets, the frequencies are reduced. Also, the natural frequencies have a tendency to decrease as the dimensionless material length scale parameter increases. This study’s outcomes may help design and manufacture micro-/nano-electro systems, sensors and actuators, small-scale devices, and other engineering structures.

Electrospinning is a scaffold fabrication technique in tissue engineering that is both versatile and promising, with the objective of repairing or enhancing damaged tissues and organs. The addition of a diverse array of additives into the polymeric matrix has resulted in the exceptional mechanical, biological and functional properties of the electrospun scaffolds in synthetic tissues, which have attracted considerable attention. This review carefully examines the role of carbon nanotubes and nanoparticles in the electrospun scaffold manufacturing process. The final properties of scaffolds, including porosity, mechanical strength and cell interaction, were also examined in relation to the differences in the diameter of electrospun fibers. The diameter of the fibers is a critical factor in the performance of the scaffold. A decrease in fiber size frequently results in an increase in bioactivity and flexibility as a result of the larger surface area. On the contrary, fiber size increases mechanical strength. Therefore, our objective is to emphasize the significance of these additives and the critical role of fiber diameter in the optimization of scaffold properties, thereby highlighting their potential to interact effectively with cells. The review concludes by highlighting future research possibilities, with a focus on the ability of additive-enhanced tissue engineering to expand its medicinal uses. Additionally, this review demonstrates that the addition of carbon nanotubes greatly improves the strength and biological activity of electrospun scaffolds, while hydroxyapatite nanoparticles stimulate bone growth, expanding the possible uses of tissue engineering. This study aims to provide a comprehensive review of recent achievements while also providing the groundwork for future research on the optimization of tissue engineering procedures through the use of innovative additives and precise control over scaffold architecture.

Infectious diseases are illnesses caused by pathogenic microorganisms, including viruses, bacteria, fungi, and parasites. These diseases can be transmitted from one individual to another, as well as through contaminated food, water, and insect bites, infectious agents invade the body, multiply, and disrupt normal bodily functions, leading to various health issues. However, due to antimicrobial resistance, the need to develop nanoenabled medicine gained significant attention recently. The management of infectious diseases using carbon nanotubes (CNTs) is an emerging field that leverages the unique properties of these nanostructures for enhanced drug delivery and therapeutic applications. Therefore, this review explores the transformative potential of CNTs in the diagnosis, prevention, and treatment of infectious diseases. As global health challenges escalate due to emerging pathogens and increasing drug resistance, the need for innovative solutions becomes critical. Moreover, the review systematically examines the unique properties of CNTs, including their mechanical, thermal, and electrical characteristics, that make them suitable for various biomedical applications. Further, the review highlights recent advancements in CNTs-based technologies, focusing on their roles in biosensing, drug deliver, and antiviral agents. Furthermore, the review also discusses how CNTs enhance the sensitivity and specificity of diagnostic tools, enabling rapid detection of infectious agents. Additionally, the multifunctional capabilities of CNTs in therapeutic applications, such as targeted drug delivery and pathogen inactivation, are also discussed. Challenges related to the clinical translation of CNTs technologies, including safety, biocompatibility, and regulatory concerns, are critically analyzed. In addition, the review concludes with clinical data by emphasizing the need for interdisciplinary collaboration to harness the full potential of CNTs in the management of infectious diseases, paving the way for future research and development in this promising field.

A brief summary is provided of selected current activities in the field of nanoelectronics, which is taken here to mean the fabrication and integration of active microelectronic components with feature dimensions of tens of nanometers or less. Particular emphasis is placed upon the classes of nanoelectronic devices that were discussed at the 2002 WOFE Conference.

A brief review is given on electronic and transport properties of carbon nanotubes mainly from a theoretical point of view. The topics include a description of electronic states in a tight-binding model and in an effective-mass or k · p scheme. Transport properties are discussed including absence of backward scattering except for scatterers with a potential range smaller than the lattice constant, its extension to multi-bands cases, and long-wavelength phonons and electron-phonon scattering.

Electronic characteristics are difficult to monitor in nanocomposites. Here we describe indirect assessments of these characteristics using THz, Raman and IR spectroscopy. Specifically we seek to gain understanding of the electron mobility in semiconductive and conductive nanostructures for electronic, electrooptic and nonlinear optical purposes.

This paper discusses the device physics of carbon nanotube field-effect transistors (CNTFETs). After reviewing the status of device technology, we use results of our numerical simulations to discuss the physics of CNTFETs emphasizing the similarities and differences with traditional FETs. The discussion shows that our understanding of CNTFET device physics has matured to the point where experiments can be explained and device designs optimized. The paper concludes with some thoughts on challenges and opportunities for CNTFET electronics.

This paper reviews our work on the development of microwave carbon nanotube resonator sensors for gas detection. The sensor consists of a radio frequency resonator coated with a layer of carbon nanotubes. Upon exposure to gasses, the resonant frequency of the sensor shifts to indicate the presence of gasses. Our experimental results demonstrate that the microwave carbon nanotube resonator sensor achieves a sensitivity of 4000 Hz/ppm upon exposure to ammonia and the resonant frequency is recovered when ammonia is evacuated. The sensing mechanism is dependent on electron transfer from the ammonia to the nanotubes. This sensor platform has great potential for wireless sensing network applications.

A simulation study using molecular dynamics and the density-functional-theory/non-equilibrium-Green's-function approach has been carried out to investigate the potential of carbon nanotubes (CNT) as molecular-scale biosensors. Single molecules of each of two amino acids (isoleucine and asparagine) were used as the target molecules in two separate simulations. The results show a significant suppression of the local density of states (LDOS) in both cases, with a distinct response for each molecule. This is promising for the prospect of CNT-based single-molecule sensors that might depend on the LDOS, e.g., devices that respond to changes in either conductance or electroluminescence.

We report results of the experimental investigation of the low-frequency noise in graphene transistors. The graphene devices were measured in three-terminal configuration. The measurements revealed low flicker noise levels with the normalized noise spectral density close to 1/f (f is the frequency) and the Hooge parameter α_H ~10^-3. Both top-gate and back-gate devices were studied. The analysis of the noise spectral-density dependence on the gate biases helped us to elucidate the noise sources in these devices. We compared the noise performance of graphene devices with that of carbon nanotube devices. It was determined that graphene devices works better than carbon nanotube devices in terms of the low-frequency noise. The obtained results are important for graphene electronic, communication and sensor applications.

Carbon-based nanoelectromechanical devices are approaching applications in electronics. Switches based on individual carbon nanotubes deliver record low off-state leakage currents. Arrays of vertically aligned carbon nanotubes or nanofibers can be fabricated to constitute varactors. Very porous, low density arrays of quasi-vertically aligned arrays of carbon nanotubes behave mechanically as a single unit with very unusual material properties.

Through silicon vias (TSVs) play a critical role in today’s microelectronic technology as they enable fabrication of three-dimensional integrated circuits. Traditionally, copper has been used to fill TSVs. However, copper is prone to electro-migration and as the size of TSVs become smaller, copper resistance increases significantly, thereby reducing its potential for TSV material at nanoscales. A proposed hybrid structure is presented here in which Carbon Nanotube (CNT) bundles are grown vertically inside TSVs and encased with copper. The CNT bundles assists with increasing the strength of the hybrid structure and is likely to enhance the reliability of the package. Thermo-mechanical stress analysis and reliability evaluations is conducted to determine the effect of CNT bundles on stress distribution in the package and their impact on reliability of other critical components such as solder bumps that are used to join the silicon layers. The finite element analysis shows that addition of CNT material to the structure, even in small volume ratios tend to redistribute the stress and refocus it to inside the CNT material rather than interfaces. Interface stresses in low strength material typically cause delamination and failure in the package. Redistribution of stress is likely to enhance the reliability of the TSVs. Additional reliability analysis of the solder joints, shows that CNT additions enhances the number of cycles to failure four times. It is hypothesized that addition of CNTs decreases the local CTE mismatch between the silicon layers and assists in reducing the stress in solder bumps. This hypothesis is proven using finite element simulations.

The structural and material properties of carbon based sensors have spurred their use in biosensing applications. Carbon electrodes are advantageous for electrochemical sensors due to their increased electroactive surface areas, enhanced electron transfer, and increased adsorption of target molecules. The bonding properties of carbon allows it to form a variety of crystal structures. This paper performs a comparative review of carbon nanostructures for electrochemical sensing applications. The review specifically compares carbon nanotubes (CNT), carbon nanofibers (CNF), and carbon nanospikes (CNS). These carbon nanostructures possess defect sites and oxygen functional groups that aid in electron transfer and adsorption processes.

The structural and electronic properties of optimized open-ended single-wall carbon nanotubes with zigzag geometry have been investigated. The calculations were performed using molecular mechanics, extended Hückel, and AM1–RHF semiempirical molecular orbital methods. It has been found that the density of states of the zigzag model is sensitive to the tube size and changes as the tube length increases. On the other hand the energetics of the tube shows an almost linear dependence to the tube length, and a converging characteristics with respect to the number of hexagons forming the tube.

The effect of chirality on the structural stability of single-wall carbon nanotubes have been investigated by performing molecular-dynamics computer simulations. Calculations have been realized by using an empirical many-body potential energy function for carbon. It has been found that carbon nanotube in chiral structure is more stable under heat treatment relative to zigzag and armchair models. The diameter of the tubes is slightly enlarged under heat treatment.

To evaluate the heat transfer performance (HTP) of hybrid nanofluids, numerical simulations are carried out in an industrial length single pass shell and tube heat exchanger. In shell, ISO VG 68 oil enters with $75^{\circ }$C and with $30^{\circ }$C, the coolant passes into the tube. CNT-${\mathrm{\text{TiO}}}_2$/water and CNT-${\mathrm{\text{TiO}}}_2$/sodium alginate (SA) are used as Newtonian and non-Newtonian hybrid nanofluid, respectively. The influence of base fluid and nanoparticles on thermal performance of heat exchanger is studied. The chosen nanoparticles are reliable to the industrial deployment. The current numerical procedure is validated with the earlier experimental results. Volume fraction of nanoparticles is optimized for an effective HTP of the heat exchanger. About 60% increment in heat transfer coefficient is observed when hybrid nanofluid is employed. By using Newtonian hybrid nanofluid, 50% improvement in Nusselt number is marked out. Effectiveness and heat transfer rate of heat exchanger are higher with the employment of Newtonian hybrid nanofluid. Results indicated that, even though Newtonian hybrid nanofluid shows higher thermal performance, non-Newtonian hybrid nanofluid is preferable for energy consumption point of view.

Carbon nanotubes (CNTs) influenced nanofluid is gaining popularity in the industry for solar energy and scratch heat exchanger applications. Consequently, this research focuses on evaluating the impact of nonlinear thermal radiation from a CNT-based nanofluid on an unsteady three-dimensional nonasymmetric Homann stagnant flux as a function of length and radius. CNTs have remarkable thermal physical properties that appear to be critical for nonlinear thermal transport. As a result, the nonlinear heat transfer properties of H₂O composed of single or multiple wall CNTs are studied. The nanomaterial has a length and radius of approximately $3\mathrm{\text{nm}}\le L\le 70\mathrm{\text{nm}}$ and $10\mathrm{\text{nm}}\le R\le 40\mathrm{\text{nm}}$. Partially differential equations with appropriate similarity transformations serve as a mathematical model for the process. The numerical solution of the simplified system of equations is achieved via the use of the well-known Runge–Kutta (RK) method in conjunction with the shooting approach. An effective way to show how a component affects velocity and temperature, skin frictions in both direction and Nusselt number are utilized in graphical representations. Increasing the unsteadiness parameter causes a reduction in the temperature profile and the velocity profile in both directions. As $\epsilon$ grows larger with $\varphi$, the skin friction in both directions decreases, while the Nusselt number profile grows larger. In addition, the variation in the Nusselt number is included in the tables, along with a comparison of the model without radiation to the model with radiation.

A nanotube is a nanometer–scale tube-like structure, it is a kind of nanoparticle, and may be large enough to serve as a pipe through which other nanoparticles can be channeled, or, depending on the material, may be used as an electrical conductor or an electrical insulator. For computing the structural information of nanotubes, the graph entropies have become the information theoretic quantities. The graph entropy measure has attracted the research community due to its potential application in discrete mathematics, biology, and chemistry. In this paper, our contribution is to explore graph entropies for structures of some nanotubes based on novel information function, which is the number of different degree vertices along with the number of edges between various degree vertices. More precisely, we computed entropies of some classes of nanotubes such as titania nanotube TNT${}_3[m,n]$, TNT${}_6[m,n]$ and carbon nanotubes HAC${}_5{C}_6{C}_7[m,n]$ by making a relation of degree-based topological indices with the help of information function.

Here we present a short summary of the “Workshop on Beam Acceleration in Crystals and Nanostructures” which has taken place at Fermilab on June 24–25, 2019.