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This study investigates the impact of Carbon Nanotubes (CNTs) and Graphene Platelets (GPLs) on the low-velocity impact behavior of curved beams. Nanofillers (CNT or GPL) are evenly distributed within each layer, but their volume fraction varies from layer to layer, creating a functionally graded pattern. The Halpin–Tsai micromechanical model is employed to predict the effective properties of the nanocomposites. The contact force between the plate and projectile is estimated using Hertzian contact law. The First-order Shear Deformation Theory (FSDT), Hamilton’s principle, finite element and Newmark integration methods are employed to model the problem. The effects of different initial velocity and mass of the impactor on the impact behavior are investigated. The analysis also takes into account the impact of different weight fractions of nanoparticles and investigates four unique reinforcement patterns: X, O, U, and V. Curved beams reinforced with GPL showed less center deflection compared to those reinforced with CNT at the same weight fraction. As the weight fraction increased, the difference in center deflection between GPL and CNT reinforcements became less significant, ultimately leading to their deflection responses converging at a weight fraction of 0.75.

Aspirations of modern high energy particle physics call for compact and cost efficient lepton and hadron colliders with energy reach and luminosity significantly beyond the modern HEP facilities. Strong interplanar fields in crystals of the order of 10–100 V/Å can effectively guide and collimate high energy particles. Besides continuous focusing crystals plasma, if properly excited, can be used for particle acceleration with exceptionally high gradients $O$(TeV/m). However, the angstrom-scale size of channels in crystals might be too small to accept and accelerate significant number of particles. Carbon-based nano-structures such as carbon-nanotubes (CNTs) and graphenes have a large degree of dimensional flexibility and thermo-mechanical strength and thus could be more suitable for channeling acceleration of high intensity beams. Nano-channels of the synthetic crystals can accept a few orders of magnitude larger phase-space volume of channeled particles with much higher thermal tolerance than natural crystals.

This paper presents conceptual foundations of the CNT acceleration, including underlying theory, practical outline and technical challenges of the proof-of-principle experiment. Also, an analytic description of the plasmon-assisted laser acceleration is detailed with practical acceleration parameters, in particular with specifications of a typical tabletop femtosecond laser system. The maximally achievable acceleration gradients and energy gains within dephasing lengths and CNT lengths are discussed with respect to laser-incident angles and the CNT-filling ratios.

Rigid carbon nanotubes in single and double walled formations, placed on a graphite surface, are bounced, rotated, slid and rolled. Various features associated with these motions are studied by assuming a 6-exp form of interaction (Van der Waal's attraction and Born–Mayer repulsion) among the C-atoms. Calculations reported here are for tubes of diameter around 14 Å, for which rigid tube approximation is known to work well. The oscillatory motion corresponding to rolling has the softest mode, whereas the one with highest frequency corresponds to bouncing. The energy barriers corresponding to these motions are also reported in this paper. The rotational and translational energy barriers for the movement of one nanotube with respect to the other one, in a double walled nanotube, have also been studied and it turns out that these tubes rotate and slide freely at room temperature. The translational energy barrier, in case of zigzag tubes, is interestingly, an order of magnitude higher than that of armchair tubes. In case of rotation, the case is reverse. Furthermore, it turns out that any drag of a concentric nanotube along the long axis direction is coupled with rotation, indicating easy screw motion instead of a simple drag. We also describe the dynamics of translational telescopic motion of a multiwalled nanotube assembly where a core oscillates within an open ended outer shell assembly.

A carbon nanotube field effect transistor (CNTFET) has been studied based on the Schrödinger–Poisson formalism. To improve the saturation range in the output characteristics, new structures for CNTFETs are proposed. These structures are simulated and compared with the conventional structure. Simulations show that these structures have a wider output saturation range. With this, larger drain-source voltage (Vds) can be used, which results in higher output power. In the digital circuits, higher Vds increases noise immunity.

Hybrid nanofluid gains attention of scientists due to its dynamic properties in various fields, and thus, hybrid nanofluids can be taken as an innovative form of nanofluids. Even though analysts acquire tremendous results in the field of hybrid nanofluids but yet no study has been carried out to predict magnetohydrodynamic effects in such fluid models. In this present analysis, influence of MHD has been investigated for the micro hybrid nanofluid over a stretched surface under convective conditions. Combine boundary layer equations for the flow have been altered into a suitable form via boundary layer approximations. Further, complete nonlinear system of equations has been numerically solved via BVP-4C method. Interesting results have been demonstrated for an exponentially stretched surface and expressed in the form of shear stress and rate of heat transfer. Results have also been visualized in the form of streamlines and isotherms. This study reveals after observing the numeric values of skin friction and Nusselt number that micropolar hybrid nanofluid models have greater heat transfer rate as compared to nanofluids.

Carbon nanotubes (CNTs) as interconnects in integrated circuits (ICs) which are vertically aligned in growth with high tube density and long tube length are required. In this paper, we present a method to improve the height of CNTs. High-resolution transmission electron microscopic (TEM) images confirm CNTs top growth mode. By cutting and modifying the top of CNTs, the influences of different radii of apertures on interconnect resistance were studied. According to the analysis, we proposed a novel growth mechanism to improve growth height of CNTs interconnection structure and the top contact resistances of pre-cutting and post-cutting CNTs interconnection structure were forecasted. The result demonstrates that the electronic performances of the post-cutting CNTs interconnection structure with platinum (Pt)-protected layer are better than the ones of pre-cutting CNTs interconnection structure. The resistivity of the post-cutting CNTs interconnection structure with Pt-protected layer is $81.2\mathrm{\text{m}}\mathrm{\Omega }\cdot \mathrm{\text{cm}}$, which is much less than that of post-cutting CNTs interconnect structure $508.8\mathrm{\text{m}}\mathrm{\Omega }\cdot \mathrm{\text{cm}}$. In what follows, the resistance of the contacted area of pre-cutting CNTs interconnection structure is 31 $\mathrm{\Omega }$, which is much less than that of post-cutting CNTs interconnection structure 439 $\mathrm{\Omega }$. This constitutes a significant step to realize longer CNTs interconnects with complementary metal oxide semiconductor (CMOS) contact modules.

Carbon nanotube field-effect transistors (CNTFETs) are excellent candidates for the replacement of traditional CMOS circuits. One of the most important modules in many arithmetic circuits is multiplier. Sometimes multipliers may occupy more area as well as consume high power which may cause speed reduction in the critical path. Compressors are important building blocks which are used in most multipliers. In this paper, a low-power architecture is proposed which can be used in compressor designs. The proposed architecture uses a low-power three-input XOR gate to reduce area, delay and power consumption. In order to evaluate the delay and power consumption of circuits, we have used four different types of compressors (3–2, 4–2, 5–2 and 7–2). These four designs were simulated using HSPICE simulation tool with 32-nm CMOS model based on 1-V and 1-GHz frequency operator. The results indicate that the proposed compressor architectures have less power–delay product (PDP) and power consumption in comparison with the existing proposed compressors.

This article investigates the flexural vibration of temperature-dependent and carbon nanotube-reinforced (CNTR) cylindrical shells made of functionally graded (FG) porous materials under various kinds of thermal loadings. The equivalent material properties of the cylindrical shell of concern are estimated using the rule of mixture. Both the cases of uniform distribution (UD) and FG distribution patterns of reinforcements are considered. Thermo-mechanical properties of the cylindrical shell are supposed to vary through the thickness and are estimated using the modified power-law rule, by which the porosities with even and uneven types are approximated. As the porosities occur inside the FG materials during the manufacturing process, it is necessary to consider their impact on the vibration behavior of shells. The present study is featured by consideration of different types of porosities in various CNT reinforcements under various boundary conditions in a single model. The governing equations and boundary conditions are developed using Hamilton's principle and solved by the generalized differential quadrature method. The accuracy of the present results is verified by comparison with existing ones and those by Navier's method. The results show that the length to radius ratio and temperature, as well as CNT reinforcement, porosity, thermal loading, and boundary conditions, play an important role on the natural frequency of the cylindrical shell of concern in thermal environment.

Carbon nanotubes (CNTs) are widely explained in fundamental blocks of nanotechnology. These CNTs exhibit much greater tensile strength than steel, even almost similar to copper, but they have higher ability to carry much higher currents, they seem to be a magical material with all these mentioned properties. In this paper, an attempt has been made to incorporate this wonder material, CNT, (with varying percentages) in polymeric matrix (Poly methyl methacrylate (PMMA)) to create a new conductive polymer composite. Various mechanical tests were carried out to evaluate its mechanical properties. The dielectric properties such as dielectric loss and dielectric constant were evaluated with the reference of temperature and frequency. The surface structures were analyzed by Scanning Electron Microscope (SEM).

There has been increasing attention to utilizing carbon nanotubes (CNTs) as nano-fillers in polymers and polymer matrix composite materials, such as carbon fiber reinforced plastics. However, the understanding of how randomly oriented CNTs affect mechanical properties of such CNT-engineered composites is limited. This paper serves to develop an analytical model for determining the elastic properties of CNT-engineered composite materials using a mechanics of materials approach. Analysis of the properties was constructed progressively using material unit cells starting from the nano level, to the micro level, and finally, to the macro level. MATLAB programming platform was used to facilitate simulation of the modeling process. Typical simulation cases of the CNT-engineered composite materials are presented in comparison with published experimental and other data, where appropriate.

Electronic devices based on carbon nanotubes (CNTs) show potential for circuit miniaturization due to their superior electrical characteristics and reduced dimensionality. The CNT field effect transistors (CNFETs) offer breakthrough in miniaturization of various electronic circuits. Investigation of ballistic transport governing the operation of CNFETs is essential for understanding the device's functional behavior. This investigation is focused on a study of current–voltage characteristics of device behavior in hard saturation region. The investigation utilizes a set of current–voltage characteristics obtained on typical devices. This work is an extension of our earlier work describing application of our approach to Si-MOSFET behavior in the saturation region.

Piezoelectric principle is one of the popular choices when it comes to mechanical energy recovery and conversion of energy into electrical energy which can be either stored or used straightaway. In general, ceramic-based piezoelectric materials like Lead Zirconate Titanate (PZT) had been the popular choice for piezoelectric devices even though they are brittle in nature and found to be toxic in long uses. At the same time, organic-based Polyvinylidene Fluoride (PVDF) and similar polymeric materials have been used in different applications with an offer of flexibility, lightweight and biocompatibility. One major factor dragging down the usage of organic materials in piezoelectric applications is their poor piezoelectric responses. In this work, authors are reporting the enhanced piezoelectric properties of nanofibers of PVDF in composite with copper nanoparticles and Multiwalled Carbon Nanotubes (MWCNTs). Fourier Transformation Infrared (FTIR) analysis has been carried out for nanofibers and was able to prove the higher beta phase conversion of PVDF in composite nanofibers when compared with pristine nanofibers. Composite nanofibers were later fabricated into a piezoelectric device with two electrodes and have shown a peak voltage of 6.78 V upon a drop test. As a proof of concept, the mentioned piezoelectric device was integrated into a shoe-based prototype where it has shown 18–20V energy harvesting upon walking at leisurely pace.

CuO/CNT composites were synthesized via simple and rapid microwave approach. The nanocomposites were characterized by X-ray diffraction (XRD), scanning electron microscopy (SEM) and X-ray photoelectron spectroscopy (XPS). Further, the electrochemical performances of CuO/CNT composites were evaluated. The prepared samples displayed high specific capacitances of 164.5Fg${}^{-1}$ at 1Ag${}^{-1}$, during the cycle process, the capacitance value aggrandized to 274.7Fg${}^{-1}$, and the capacitance remained at 166% of the primary value after 10 000 turns. Moreover, the CuO/CNT//AC asymmetric supercapacitor (ASC) exhibited an energy density of 17.08Whkg${}^{-1}$ at 775Wkg${}^{-1}$ and excellent electrochemical stability in 6M KOH aqueous electrolyte, showing its enormous potential in energy-storage devices.

A graphene and carbon nanotube (CNT) array composite was synthesized by chemical vapor deposition (CVD) and chemically treated after synthesis, yielding a novel corrugated structure, visually similar to a mushroom gill. This binder-free hybrid material was used to make an electrode that may find application in energy storage devices, such as supercapacitors. The electrode performance of the corrugated graphene/CNT array composite (CGCC) was compared to that of commercial glassy carbon. The results of the comparison are presented here, along with suggestions for further development of the CGCC electrode.

Aspirations of modern high energy particle physics call for compact and cost efficient lepton and hadron colliders with energy reach and luminosity significantly beyond the modern HEP facilities. Strong interplanar fields in crystals of the order of 10−100 V/Å can effectively guide and collimate high energy particles. Besides continuous focusing crystals plasma, if properly excited, can be used for particle acceleration with exceptionally high gradients O(TeV/m). However, the angstrom-scale size of channels in crystals might be too small to accept and accelerate significant number of particles. Carbon-based nano-structures such as carbon-nanotubes (CNTs) and graphenes have a large degree of dimensional flexibility and thermo-mechanical strength and thus could be more suitable for channeling acceleration of high intensity beams. Nano-channels of the synthetic crystals can accept a few orders of magnitude larger phase-space volume of channeled particles with much higher thermal tolerance than natural crystals.

This paper presents conceptual foundations of the CNT acceleration, including underlying theory, practical outline and technical challenges of the proof-of-principle experiment. Also, an analytic description of the plasmon-assisted laser acceleration is detailed with practical acceleration parameters, in particular with specifications of a typical tabletop femtosecond laser system. The maximally achievable acceleration gradients and energy gains within dephasing lengths and CNT lengths are discussed with respect to laser-incident angles and the CNT-filling ratios.

Carbon nanotubes (CNTs) have attracted considerable interest because of their unique physical, electrical properties and many potential applications. Carbon nanotubes are considered to be the most promising candidate in electrode materials for secondary battery, solar cell and supercapacitor. Non-conductive substrates, such as silicon wafers have usually been used to synthesize CNTs. However, in applications such as electrodes, it is desirable to have CNTs grown on conductive buffer layer and conductive substrates. We researched the fabrication of carbon nanotubes on Ni/TiO₂/Ti substrate by Thermal chemical vapor deposition (TCVD). Experimental parameter is synthesis temperature, time and buffer layer thickness. The samples were characterized by means of field emission scanning electron microscopy (FE-SEM), Raman spectroscopy analysis, transmission electron microscope (TEM) and electrochemical test. The synthesized CNTs have the diameter of about 100~200 nm and the length of about 5~10 μm. Li/CNTs cell with CNTs on Ti substrate exhibited good charge/discharge behavior and slow capacity fading.