A new class of lightweight, multifunctional material has been developed for electromagnetic compatibility. This material, branded VeeloSTRIKE, was designed to provide lightning strike protection, broadband shielding, and electrical uniformity in carbon fiber reinforced polymer composites. Aerospace and defense prime contractors and integrators are evaluating this proprietary carbon nanotube blended material to improve hardening against electromagnetic environment effects, such as lightning strike protection, electromagnetic pulse, high intensity radiated fields, electromagnetic interference, and electrostatic discharge. This material is targeted as an alternative to heavy metals, particularly expanded metal foils, woven mesh, and filled polymers. VeeloSTRIKE is between one-third and one-half the weight of tradition metallic solutions while providing enhanced high-frequency shielding effectiveness and protecting against Zone 1A lightning.

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The Concept of Joint Criminal Enterprise widely used in International Criminal Law as a means of assigning individual criminal culpability. This paper presents the evolution of the concept and covers the fundamental tenets of JCE.

Vertically aligned arrays of multiwall carbon nanotubes (MWCNT) were decorated with gold (Au) nanoparticles of different diameter and areal densities and spun into yarns. The melting point of Au nanoparticles determined by differential scanning calorimetry was approximately 260°C, well below the oxidation temperature of carbon. A continuous yarn was formed while pulling out a bundle of CNTs from the metalized CNT array. Relatively low temperature (300°C) thermal processing of the metalized yarn resulted in a 30% improvement in thermal conductivity, 40% increase in electrical conductivity and a 4× increase in elastic modulus. Cross-sections of the yarn were examined with transmission electron microscopy to characterize the physical nature of the metal–nanotube interface. The deposition procedure described to decorate the nanotube yarns is easily scalable to larger CNT arrays or other configurations for commercial applications, such as medical implants, lightweight conductors, smart uniforms for the soldiers, and conformal electronics in aerospace industry.

When a legal dispute involves an element of Foreign Law, two choices spring up. Either ignore the foreign law element or abide by the foreign law legal principles. This article explains, in brief the mechanism to be adopted in Private International Law, if the latter choice is made.

Substantive Legitimate Expectations arise in Administrative Law in certain specified instances where mere procedural protection of the expectation is insufficient. This paper argues that the concept has grown our of the concept of "abuse of power". However, Coughlan case in the UK, Teoh in Australia, Mowjood case in Sri Lanka have imparted new life to the concept. But it is argued in this paper that the corpus of Substantive Legitimate Expectations are already covered by doctrine of proportionality and Wednesbury Unreasonableness.

We compared mechanical and electrical properties of carbon nanotube (CNT) yarns formed from four different spinning methods. In these methods, a yarn was spun from two aligned CNT arrays. CNT yarns fabricated from each method were tested quantitatively through the mechanical and electrical properties and reported. This improvement is considered to be caused by multiple factors, such as reduction of the yarn diameter, densification, water evaporation, and CNT orientation. The best electrical and mechanical property of CNT yarn was observed from the fourth spinning method where heating and tension during spinning were applied. The introduced yarn spinning methods are appropriate for continuous mass production of high strength carbon nanotube yarns with controlled diameter, strength, and electrical conductivity.

We report mechanical, thermal, and electrical properties of novel sheet materials composed of multiwalled carbon nanotubes, drawn from a CNT array. At low loading there is some slippage of CNTs but at higher loading tensile strength σ0=7.9MPa and Young’s modulus E=310MPa. The room-temperature thermal conductivity of the CNT sheet was 2.5±0.5Wm−1K−1, giving a thermal conductivity to density ratio of κ/ρ=65Wm−1K−1g−1cm3. The heat capacity shows 1D behavior for T>40K, and 2D or 3D behavior at lower temperatures. The room-temperature specific heat was 0.83Jg−1K−1. The iV curves above 10K have Ohmic behavior while the iV curve at T=2K is non-Ohmic, and a model to explain both ranges is presented. Negative magnetoresistance was found, increasing in magnitude with decreasing temperature (−15% at T=2K and B=9T). The tensile strength, Young’s modulus and electrical conductivity of the CNT sheet are low, in comparison with other CNT materials, likely due to defects. Thermal conductivity is dominantly phononic but interfacial resistance between MWCNTs prevents the thermal conductivity from being higher.

The electrical resistivity of CNT yarns of diameters 10–34μm, spun from multi-walled carbon nanotube arrays, have been determined from 2 to 300K in magnetic fields up to 9T. The magnetoresistance is large and negative at low temperatures. The thermal conductivity also has been determined, by parallel thermal conductance, from 5 to 300K. The room-temperature thermal conductivity of the 10μm yarn is (60±20)Wm−1K−1, the highest measured result for a CNT yarn to date. The thermal and electrical conductivities both decrease with increasing yarn diameter, which is attributed to structural differences that vary with the yarn diameter.

Nanothread with a diameter as small as one hundred nanometers was manufactured under a scanning electron microscope. Made directly from carbon nanotubes, and inheriting their superior electrical and mechanical properties, nanothread may be the world’s smallest man-made fiber. The smallest thread that can be spun using a bench-top spinning machine is about 5 microns in diameter. Nanothread is a new material building block that can be used at the nanoscale or plied to form yarn for applications at the micro and macro scales. Preliminary electrical and mechanical properties of nanothread were measured. The resistivity of nanothread is less than 10−5 Ω∙m. The strength of nanothread is greater than 0.5 GPa. This strength was obtained from measurements using special glue that cures in an electron microscope. The glue weakened the thread, thus further work is needed to obtain more accurate measurements. Nanothread will have broad applications in enabling electrical components, circuits, sensors, and tiny machines. Yarn can be used for various macroscale applications including lightweight antennas, composites, and cables.

CNT arrays were synthesized by Chemical Vapor Deposition (CVD) and spun into ribbons, which were coated using Atmospheric Pressure Microwave Plasma system. Time-of-Flight Secondary Ion Mass Spectrometry (TOF-SIMS) characterization of CNT ribbons indicated the presence of polymer films with CF2 as a repeat unit. Atomic concentration of C, F and O in the coated films was estimated from X-ray Photoelectron Spectroscopy (XPS) data. Types of bonding between the elements in the coated films was studied by curve fitting of C 1s XPS spectra.

Spinning carbon nanotube (CNT) thread directly from 4–6 mm long aligned carbon nanotube arrays is reported here. The strength of carbon nanotube thread was improved by optimizing the chemical vapor deposition parameters for growing long aligned carbon nanotube arrays. The morphological and structural characterization of CNT arrays and threads were studied by Raman spectroscopy, transmission electron microscopy, and scanning electron microscopy. After optimization of growth parameters threads were spun with diameters between 10 and 70 μm. We have achieved thread strength of about 280 MPa.

Carbon nanotubes (CNTs) have properties that promise an exciting role in nervous tissue repair. CNTs are strong, extremely light weight, biocompatible and electrically conductive. A relatively novel form of CNT material, multiple strands of CNTs spun into thread, accentuates the linear geometry of CNTs while retaining electrical conductivity. We propose that CNT thread, which is strong, pliable and readily manipulated, has the potential to support longitudinal growth of nerves after injury, in nervous system prostheses. Towards understanding how CNT materials support nervous tissue regeneration, we examined the in vitro interactions between CNT materials and neural stem cell-containing neurospheres, prepared from newborn mouse cortices. Intact neurospheres attached to pieces of as-grown arrays of CNTs, CNT "ribbon" material pulled from the arrays, and CNT thread. Stem cells differentiated into both neurons and glia under these conditions. Processes and cells aligned with the longitudinal axis of the CNT materials, both with and without coatings. For comparisons, dissociated neurosphere cells were plated on CNT thread, polypropylene surgical suture thread and commercial carbon fibers. Initial cell attachment (within seconds) and attachment at 24 h was greater on CNT thread than on the other fiber types. Stem cells on CNT threads differentiated into neurons and astrocytes over several days, on all fibers. The presence of serum greatly aided the health and spreading of both neurons and astrocytes. These findings demonstrate that CNT materials, in particular the thread form, are viable preparations for neural cell attachment, outgrowth and differentiation.

A biosensor is an electronic device that measures biologically important parameters. An example is a sensor that measures the chemicals and materials released during corrosion of a biodegradable magnesium implant that impact surrounding cells, tissues and organs. A responsive biosensor is a biosensor that responds to its own measurements. An example is a sensor that measures the corrosion of an implant and automatically adjusts (slows down or speeds up) the corrosion rate. The University of Cincinnati, the University of Pittsburgh, North Carolina A&T State University, and the Hannover Medical Institute are collaborators in an NSF Engineering Research Center (ERC) for Revolutionizing Metallic Biomaterials (RBM). The center will use responsive sensors in experimental test beds to develop biodegradable magnesium implants. Our goal is to develop biodegradable implants that combine novel bioengineered materials based on magnesium alloys, miniature sensor devices that monitor and control the corrosion, and coatings that slow corrosion and release biological factors and drugs that will promote healing in surrounding tissues. Responsive biosensors will monitor what is happening at the interface between the implant and tissue to ensure that the implant is effective, biosafe, and provides appropriate strength while degrading. Corrosion behavior is a critical factor in the design of the implant. The corrosion behavior of implants will be studied using biosensors and through mathematical modeling. Design guidelines will be developed to predict the degradation rate of implants, and to predict and further study toxicity arising from corrosion products (i.e., Mg ion concentrations, pH levels, and hydrogen gas evolution). Knowing the corrosion rate will allow estimations to be made of implant strength and toxicity risk throughout the degradation process.

Vertically aligned multi-walled carbon nanotube (MWCNT) arrays up to ∼6 mm high with an array density of 0.06 g cm−3 have been grown by chemical vapor deposition. Thermal conductivities (κ) and electrical conductivities (σ) were determined from 5 K to 390 K. The range for κ at 300 K is 0.5–1.2 W m−1 K−1 along the tube growth direction, with the shortest array having the highest κ, and an order of magnitude lower in the direction perpendicular to the tubes. The same trends also were evident for electrical conductivity, i.e., decreasing values with increasing array height and conductivity an order of magnitude lower in the perpendicular direction. Values of σ ranged from 7 to 14 S cm−1 along the array at 300 K. The Seebeck coefficient is ∼20 μV K−1 at 300 K. The effective Lorentz number indicates that thermal conductivity in the carbon nanotube arrays is phonon dominated over the full temperature range.

Laminated composite materials can reach high mechanical properties at low weight. Composite materials, however, are susceptible to damage due to their low interlaminar mechanical properties and poor heat and charge transport in the transverse direction to the laminate. Moreover, methods to inspect and ensure the reliability of composites are expensive and labor intensive. Recently carbon nanotube forests were spun into thread that is tough and electrically conductive. The thread was integrated into composite materials and used for the first time as a sensor to monitor strains and detect damage including delamination in the material. These self-sensing composites were found to be very sensitive to damage and will help to revolutionize the maintenance of composite structures, which will now be based on their condition and not their amount of use.

Individual nanotubes made of carbon, boron nitride, iron, silicon, or other materials have properties such as high strength, toughness, electrical and thermal conductivity, and light weight that cannot be matched by conventional materials. Nanotubes also change their properties in response to external fields and change one type of energy into another, which are useful for design. This article explores three main steps in exploiting responsive materials based on nanotubes: nanotube synthesis, macroscale material fabrication, and incorporation into device structures for novel applications. Nanotubes are always synthesized as individual particles in the form of powders, smoke particles, or aligned forests. To be industrially important, nanotubes generally must be processed to form derivative materials such as functionalized/coated powders and forests and macroscale intermediate materials such as sheets, ribbon, and yarn. The processed nanotubes are then used to develop responsive materials and devices that are able to resist, react to, or generate energy from their environment. This article provides background information and ideas on how to develop nanotube responsive materials for everyday use.