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Nanotechnology is an emerging technology and it brings a tremendous change to human life and economy. When the size of a material is reduced to the nanoscale, its properties may change significantly and becomes a new substance. A fullerene is a molecule of carbon in the shape of a hollow sphere, ellipsoid, tube, and many other geometrical structures. For example, buckyballs are spherical fullerenes and carbon nanotubes are cylindrical fullerenes. Fullerenes have been under intensive investigation for their expanding applications in electronics, energy, medicine, and many other research fields. Nanostructure analysis is very important for understanding the formation of different materials and their properties. In this study, a virtual laboratory is developed for learning fullerene production and its nanostructure analysis. The learners can use the arc discharge equipment to produce fullerenes and then use the transmission electron microscope (TEM) to observe the nanostructures of different fullerene samples. The high interactivity and 3D visual effects of the virtual laboratory enable the learners to become familiar with the geometrical structures and properties of fullerenes. A teaching experiment has been conducted and the results show that the virtual laboratory can improve their learning motivation and effectiveness. [ABSTRACT FROM AUTHOR]

Composites of carbon nanostructures (CNSs) and biocompatible polymers are promising materials for a series of advanced technological applications, ranging from biomedicine and bioelectronics to smart packaging and soft robotics. In this work, we present three types of organic-functionalized CNSs, namely p -methoxyphenyl functionalized multi-walled carbon nanotubes, carbon nanohorns and reduced graphene oxide, used as nanofillers for the preparation of homogeneous and well-dispersed composites of poly( l -lactic acid), a biocompatible and biodegradable FDA-approved polymer. A thorough characterization of the composites is given in terms of calorimetric response, electrical and mechanical properties. Significant differences are observed among the different types of CNS nanofillers, underlying the key role played by the nanoscale shape and distribution of the components in driving the macroscopic behavior of the composite material. Surface properties are probed through advanced atomic force microscopy techniques, on both flat substrates (films) and confined systems (nanofibers). All these composites proved to be biocompatible and to support as scaffolds the proliferation of human neuronal precursor cell line SH-SY5Y, opening the route to a future comparative analysis on their ability to boost neuronal differentiation. [ABSTRACT FROM AUTHOR]

One of the primary factors affecting the effectiveness of nanomaterials in enhancing cement composites properties is its ability to disperse efficiently without aggregation. To-date a number of methods have been proposed to increase the dispersion of CNTs in the mixes. Studies have shown that the response of cement-based materials to CNT addition can vary depending on the dispersion mechanism employed. Despite the need, there is no standardized methodology used to disperse CNTs, and consequently, it is hard to model the behavior. This study focused on using design of experiments (DOE) to assess the effect of dispersion protocol on the characteristics of cement-based composites. Experiments were carried out with different procedures to compare the effect of wet and dry mixing of CNTs, sonication exposure time, whisking and CNTs concentration on the mechanical properties of mortar blocks. Response Surface Methodology (RSM) was used to model the experimentally determined compressive strength. The model was further validated by comparing its predictions with other experimental scenarios. The model can be used to determine the optimum methodology to disperse CNTs in cement composites. To compare experimental data, there is a need to provide the exact details of all steps involved in a dispersion protocol that is captured by the proposed model. Following the suggested protocol for specimen preparation can ensure achieving a high level of dispersion and superior performance. [ABSTRACT FROM AUTHOR]

Direct visualization of one-dimensional (1D) materials under an optical microscope in ambient conditions is of great significance for their characterizations and applications. However, it is full of challenges to achieve such goal due to their relative small size (ca. 1 nm in diameter) in the optical-diffraction-limited laser spot (ca. 1 μm in diameter). In this Concept article, we introduce a polarization-based optical homodyne detection method that can be used as a general strategy to obtain high-throughput, real-time, optical imaging and in situ spectroscopy of polarization-inhomogeneous 1D materials. We will use carbon nanotubes (CNTs) as an example to demonstrate the applications of such characterization with respect to the absorption signal of individual nanotubes, real-time imaging of individual nanotubes in devices, and statistical structure information of nanotube arrays. [ABSTRACT FROM AUTHOR]

Recently, a great interest has been paid to the development of hybrid protein-inorganic nanoparticles (NPs) for drug delivery and cancer diagnostics in order to combine the merits of both inorganic and protein nanocarriers. This review primarily discusses the most outstanding advances in the applications of the hybrids of naturally-occurring proteins with iron oxide, gadolinium, gold, silica, calcium phosphate NPs, carbon nanotubes, and quantum dots in drug delivery and cancer imaging. Various strategies that have been utilized for the preparation of protein-functionalized inorganic NPs and the mechanisms involved in the drug loading process are discussed. How can the protein functionalization overcome the limitations of colloidal stability, poor dispersibility and toxicity associated with inorganic NPs is also investigated. Moreover, issues relating to the influence of protein hybridization on the cellular uptake, tumor targeting efficiency, systemic circulation, mucosal penetration and skin permeation of inorganic NPs are highlighted. A special emphasis is devoted to the novel approaches utilizing the protein-inorganic nanohybrids in combined cancer therapy, tumor imaging, and theranostic applications as well as stimuli-responsive drug release from the nanohybrids. [ABSTRACT FROM AUTHOR]

This article presents the technical characteristics of a newly built small- and wide-angle X-ray scattering (SAXS/WAXS) apparatus dedicated to structural characterization of a wide range of nanomaterials in the powder or dispersion form. The instrument is based on a high-flux rotating anode generator with a molybdenum target, enabling the assessment of highly absorbing samples containing heavy elements. The SAXS part is composed of a collimation system including a multilayer optic and scatterless slits, a motorized sample holder, a vacuum chamber, and a two-dimensional image-plate detector. All the control command is done through a TANGO interface. Normalization and data correction yield scattering patterns at the absolute scale automatically with a q range from 0.03 to 3.2 Å−1. The WAXS part features a multilayer collimating optic and a two-dimensional image-plate detector with variable sample-to-detector distances. The accessible q range is 0.4-9 Å−1, ensuring a large overlap in q range between the two instruments. A few examples of applications are also presented, namely coupled SAXS/WAXS structure and symmetry determination of gold nanocrystals in solution and characterization of imogolite nanotubes and iron-filled carbon nanotube samples. [ABSTRACT FROM AUTHOR]

A controlledassembly and alignment of carbon nanotubes (CNTs) in a high-packingdensity with a scalable way remains challenging. This paper focuseson the preparation of self-assembled and well-aligned CNTs with adensely packed nanostructure in the form of buckypaper via a simplefiltration method. The CNT suspension concentration is strongly reflectedin the alignment and assembly behavior of CNT buckypaper. We furtherdemonstrated that the horizontally aligned CNT domain gradually increasesin size when increasing the deposited CNT quantity. The resultantaligned buckypaper exhibited notably enhanced packing density, strength,modulus, and hardness compared to previously reported buckypapers. [ABSTRACT FROM AUTHOR]

The relationship between surface coverage of the shell layer in core‐shell nanostructured electrodes and the resulting electrochemical performance of the electrodes is described. Systematic studies and theoretical modeling reveal that partially covered core‐shell nanostructured electrodes are beneficial to release the stress induced by lithiation and delithiation, leading to the excellent cycle performance without any capacity fading up to 50 cycles. [ABSTRACT FROM AUTHOR]

Carbon nanotubes (CNTs) with their different types have several potential future applications, including on-chip integrated electronic devices. The growth control of CNTs in the desired shape is important to realise such devices. A method to control the growth of CNTs in a desired spiral shape or other similar shapes on silicon (Si) substrates is proposed. Multi-walled carbon nanotube growth in a circular spiral shape is demonstrated by using a trenched-patterned-shape on the Si substrate method. The growth concept, the growth and fabrication steps, and the growth and fabrication results are presented. [ABSTRACT FROM AUTHOR]

Nanostructures, such as carbon nanotubes, are often added to polymers and composites to enhance their strength. The extreme mechanical properties of carbon nanotubes suggest an obvious rationale behind this approach. However as Markus Buehler and Isabelle Su at Massachusetts Institute of Technology in the US highlight in their recent topical review [1] the behaviour that renders nanomaterials soft or strong can be far from trivial, often involving interactions on a range of scales from macrostructures to nanostructures and—in the case of biostructures—the amino acids and proteins they are built from. [ABSTRACT FROM AUTHOR]

A controllable nanoscale rotating actuator system consisting of a double carbon nanotube and graphene driven by a temperature gradient is proposed, and its rotating dynamics performance and driving mechanism are investigated through molecular dynamics simulations. The outer tube exhibits stable pure rotation with certain orientation under temperature gradient and the steady rotational speed rises as the temperature gradient increases. It reveals that the driving torque is caused by the difference of atomic van der Waals potentials due to the temperature gradient and geometrical features of carbon nanotube. A theoretical model for driving torque is established based on lattice dynamics theory and its predicted results agree well with molecular dynamics simulations. Further discussion is taken according to the theoretical model. The work in this study would be a guide for design and application of controllable nanoscale rotating devices based on carbon nanotubes and graphene. [ABSTRACT FROM AUTHOR]

Using spin-polarized density functional theory calculations, we study binding properties of small metal nanoclusters (Cu13 and Al13) onto carbon nanotubes (CNTs). On defect-free CNTs, the binding affinity with the Cu or Al cluster is very weak. When various defects such as vacancies, substitutional nickel defects, and nickel adatoms are introduced in CNTs to increase the binding strength, the binding energies of the metal nanoclusters increase substantially irrespective of types of defects. The effect of the Ni adatom is especially noticeable. Our results propose a method for improving the wettability of metal–CNT complex composites. [ABSTRACT FROM AUTHOR]