Browse Topic: Carbon nanotubes

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Optical Black Coatings On Carbon Fiber Reinforced Composite Sandwich Structure With Aluminum Honeycomb Core For Satellites Applications.2022-26-114105/26/2022
The composite sandwich structure has been in use in space applications as a result of its high strength to weight ratio coupled with excellent compressibility strength. In particular, there has been tremendous demand for honeycomb sandwich structures for satellite application in recent years. Currently, a major problem needs to be addressed concerning reflections from satellite structures which leads to capturing in-accurate data of celestial bodies by ground-based astronomy. In the light of the above, this paper focuses on the development of novel optical black coatings on Carbon fiber reinforced composite sandwich structures with aluminum honeycomb core. A thin layer of Multi-Walled Carbon Nanotubes black coatings was developed on the surfaces of Carbon fiber reinforced composite laminate of the sandwich structure using Chemical Vapour Deposition technique, to provide low scattering and low reflective surface. Three-point bending test are performed for evaluating the Youngs modulus
CS PhD, Ramesh, J, Sudharshan, Chaurasia, P Harsh
Numerical analysis of flame temperature and Intermediate Product Concentration in micro-scale coaxial diffusion combustion of methanol2022-01-085403/29/2022
As an excellent nanoscale material, carbon nanotubes play a very important role in improving the batteries of new energy vehicles. The micro-scale combustion flame synthesis method is a promising method for preparing carbon nanotubes. In order to explore the optimal growth condition of carbon nanotubes under micro-scale combustion, the detailed mechanism of methanol C3 (114 species, 1999 reactions) was reduced based on whole-species sensitivity analysis, then a suitable model of methanol combustion was established by using Fluent software coupling with simplified mechanism (16 species, 65 reactions) of methanol. The model was used for the numerical simulation of micro-scale coaxial diffusion combustion of methanol, and then it was verified by the experimental results of micro-scale combustion of methanol. They were analyzed that the flame temperature field and important intermediate product concentration (CO, OH and HCO) under different methanol flow and air flow. The results show that
zhang, peng, Ni, Jimin, Shi, Xiuyong
Interlaminar Properties Improvement of Nanocomposites Using Coiled Nanomaterials2021-01-002703/02/2021
In this research helical Carbon Nanotubes (CNTs) with various weight percentages as an additional reinforcement were used. The objective was to investigate the effectiveness of helical geometries of the CNTs to form interlocking mechanisms with the resin and the traditional microfiber reinforcements to improve the overall performance of the composite structures and assemblies. In this study, ASTM D2344/2344M-16 is used to study the short beam strength of the laminated nanocomposites and evaluate the benefit of the mechanically interlocked helical CNTs reinforcement. Overall, three sets of composite laminates (i.e., with neat epoxy, and with two different wt% of Helical CNTs reinforced epoxy) were fabricated per ASTM standard D2344/2344M-16. Adequate test specimens were prepared and then they were tested per ASTM standard. The test results were analyzed and evaluated to determine the effects of helical CNTs on short beam strength of the laminated nanocomposites.
Sritharan, Ramanan, Askari, Davood
New Materials Boost Efficiency and Stability of Optical RectennasTBMG-3848602/01/2021
Rectennas convert electromagnetic fields at optical frequencies directly to electrical current. Optical rectennas operate by coupling light’s electromagnetic field to an antenna. The electromagnetic field creates an oscillation in the antenna, producing an alternating flow of electrons. When the electron flow reaches a peak at one end of the antenna, the diode closes, trapping the electrons, then re-opens to capture the next oscillation, creating a current flow. This switching must occur at terahertz frequencies to match the light. The junction between the antenna and diode must provide minimal resistance to electrons flowing through it while open, yet prevent leakage while closed.
Platform Monitors Gut MicrobiomeTBMG-3855302/01/2021
Scientists are developing a platform that can monitor and model the real-time processing of gut microbiome serotonin activity. Their goal is to one day package the platform into an ingestible capsule capable of detecting, treating, and monitoring GBA diseases. The platform provides access to the specific site of serotonin production, important because serotonin is secreted from the bottoms of cells. An innovative porous membrane with an integrated serotonin sensor on which a model of the gut lining can be grown allowed researchers to access both top and bottom sides of the cell culture.
Radiation Effects on Electronics in Aligned Carbon Nanotube Technology (RadCNT)21AERP02_0702/01/2021
Characterizing the fundamental mechanisms and charge transport phenomena governing the interactions between ionizing and non-ionizing radiation with carbon-based (nanotube and graphene) field-effect transistors (FETs) devices and integrated circuits (ICs). Defense Threat Reduction Agency, Fort Belvoir, Virginia The main objective of the RadCNT program was the characterization of fundamental mechanisms and charge transport phenomena governing the interactions between ionizing and nonionizing radiation with carbon-based (nanotube and graphene) field-effect transistors (FETs) devices and integrated circuits (ICs). This effort was supported through the fabrication of aligned single-walled carbon nanotubes (SWCNT) FETs at the University of Southern California's (USC) Nanotechnology Research Laboratory and through a collaboration with the Naval Research Laboratories (NRL) for radiation testing and expertise in radiation effects characterization. The RadCNT program concentrated on
A Near-Perfect Blackbody Calibration TargetTBMG-3849702/01/2021
Researchers at NASA’s Jet Propulsion Laboratory have developed a robust alternative to the blackbody targets typically used to calibrate optical/thermal imaging systems. Typically, blackbody targets are formed via additive processes (e.g., high-emissivity paint, carbon nano tubes). JPL’s innovation utilizes highly doped black silicon formed via inductively coupled plasma (ICP) etching at cryogenic temperatures (i.e., a subtractive process), providing an ultrahigh-emissivity surface.
Composite Material Increases Electrical Current Capacity of Copper WiresTBMG-3797111/01/2020
Researchers have created a composite material that increases the electrical current capacity of copper wires. The research is aimed at reducing barriers to wider electric vehicle adoption including cutting the cost of ownership and improving the performance and life of components such as electric motors and power electronics. The material can be deployed in any component that uses copper including more efficient bus bars and smaller connectors for electric vehicle traction inverters, as well as for applications such as wireless and wired charging systems.
E-Tongue Nanosensor ArrayTBMG-3799511/01/2020
E-Tongue, a patent-pending technology, is comprised of a silicon-based interdigitated electrode (IDE) array with nanostructured materials that can detect biomolecules and chemical compounds in a liquid sample.
Using Silicon for Battery AnodesTBMG-3779110/01/2020
The same material used in pencils (graphite) has long been a key component in today's lithium-ion batteries. As reliance on these batteries increases, however, graphite-based electrodes are due for an upgrade.
E-Skin Powered by Sweat Can Monitor HealthTBMG-3713006/01/2020
A researcher has developed an electronic skin that is applied directly on top of real skin. The e-skin, made from soft, flexible rubber, can be embedded with sensors that monitor information like heart rate, body temperature, levels of blood sugar, and metabolic byproducts that are indicators of health, and even the nerve signals that control muscles. It does so without the need for a battery, as it runs solely on bio-fuel cells powered by one of the body’s own waste products.
3-Dimensional Numerical Simulation on CuO Nanofluids as Heat Transfer Medium for Diesel Engine Cooling System2020-01-110904/14/2020
CuO-water nanofluids was utilized as heat transfer medium in the cooling system of the diesel engine. By using CFD-Fluent software, for 0.5%, 1%, 3% and 5% mass concentration of nanofluids, 3-dimensional numerical simulation about flow and heat transfer process in the cooling system of engine was actualized. According to stochastic particle tracking in turbulent flow, for solid-liquid two phase flow discrete phase, the moving track of nanoparticles was traced. By this way, for CuO nanoparticles of different mass concentration nanofliuds in the cooling jacket of diesel engine, the results of the concentration distribution, velocity distribution, internal energy variation, resident time, total heat transfer and variation of total pressure reduction between inlet and outlet were ascertained. It is proved by simulation results that nanofluids as heat transfer medium can evidently enhance diesel engine heat transfer capability, when the concentration of nanoparticles increases, the
Yang, Shuai, Yang, Xiaolin, Liu, Haifeng, Li, Xiuyuan
High Thermally Conductive Polymeric CompositesTBMG-3639504/01/2020
There has been much interest in developing polymeric nanocomposites with ultra-high thermal conductivities such as with exfoliated graphite or carbon nanotubes. These materials exhibit thermal conductivity of 3,000 W/mK measured experimentally and up to 6,600 W/mK predicted from theoretical calculations. But when added to polymers, the expected thermal conductivity enhancement is not realized due to poor interfacial thermal transfer.
Effects of Helical Carbon Nanotubes on Mechanical Performance of Laminated Composites and Bonded Joints2020-01-002903/10/2020
Most composite assemblies and structures generally fail due to weak interlaminar properties and poor performance of their bonded joints that are assembled together with an adhesive layer. Adhesive failure and cohesive failure are among the most commonly observed failure modes in composite bonded joint assemblies. These failure modes occur due to the lack of reinforcement within the adhesive layer in transverse direction. In addition, the laminated composites fail due to the same reason that is the lack of reinforcement through the thickness direction between the laminae. The overall performance of any composite structures and assemblies largely depends on the interlaminar properties and the performance of its bonded joints. Various techniques and processes were developed in recent years to improve mechanical performance of the composite structures and assemblies, one of which includes the use of nanoscale reinforcements in between the laminae and within the adhesive layer. However
Sritharan, Ramanan, Askari, Davood
Conductive Polymer/Carbon Nanotube Structural MaterialsTBMG-3617203/01/2020
Carbon nanotubes (CNTs) show promise for multifunctional materials for a range of applications due to their outstanding combination of mechanical, electrical, and thermal properties. These promising mechanical properties, however, have not translated well to CNT nanocomposites fabricated by conventional methods due to the weak load transfer between tubes or tube bundles.
Breathalyzer Detects MarijuanaTBMG-3597102/01/2020
As recreational marijuana legalization becomes more widespread in the U.S., so has concern about what that means for enforcing driving-under-the-influence (DUI) laws. Unlike a breathalyzer used to detect alcohol, police do not have a device that can be used in the field to determine if a driver is under the influence of marijuana.
Liquid-Metal Wearable Pressure Sensor Created for Health Monitoring ApplicationsTBMG-3600902/01/2020
KAIST Daejeon, Republic of Korea
Process Synthesizes Carbon Nanotubes Using Carbon DioxideTBMG-3596102/01/2020
Carbon nanotubes are supermaterials that can be stronger than steel and more conductive than copper. The reason they're not in every application from batteries to tires is that these properties only show up in the tiniest nanotubes, which are extremely expensive. A new process was developed that can make these materials from carbon dioxide drawn from the air, in a way that is much less expensive than other methods. These materials could impact how emissions can be used in future technology.
Method Makes Transistors and Electronic Devices from ThreadTBMG-3546711/01/2019
A transistor has been made from linen thread, enabling the creation of electronic devices made entirely of thin threads that could be woven into fabric, worn on the skin, or implanted surgically for diagnostic monitoring. The flexible electronic devices could enable a range of applications that conform to different shapes and allow free movement without compromising function.
Printed Electronics for Electrified Tattoos and Personalized BiosensorsTBMG-3545811/01/2019
A fully print-in-place technique for electronics could enable technologies such as high-adhesion, embedded electronic tattoos and bandages with patient-specific biosensors.
Investigation of Machinability Characteristics on Turning of Nimonic 90A Using Al 2 O 3 and CNT Nanoparticle in Groundnut Oil2019-28-007210/11/2019
Nimonic 90A alloy is a nickel-chromium-cobalt alloy and found as a potential material for turbine blades, discs, forgings, a ring section, and hot-working tools. This paper presents the effect of concentration along with cutting speed and feed rate on Fz: cutting force, Ra: surface roughness and Vba: tool wear with the application of two different nanofluids (NFS) on turning of Nimonic 90A by TiAlN PVD carbide cutting inserts. The nanoparticles suspended in oil taken for present investigation are nAl2O3, nCNT, and groundnut oil. The Taguchi L9 orthogonal array and derringer’s desirability response surface has been employed for parameter design and optimal search. 3D surface plots, factor effect plots, Taguchi S/N, and variance tests are used to study the effect of concentration on the machining performance of Nimonic 90A. The statistical analysis revealed % concentration for nCNT and cutting speed for nAl2O3 are found as an influenced parameter on performance characteristics. From the
Kannan, Venkatesan, Sundararajan, Devendiran
A Study and Mathematical Analysis of Thermionic Energy Conversion Materials Based on Their Solid State Emission Properties2019-28-008410/11/2019
The physical mechanism of direct energy conversion technology for space applications is well known for over a century. Whereas thermionic energy conversion is now being explored for automotive regeneration applications considering its high conversion efficiency. The thermionic emission used in space applications has operating temperatures >20000C which is much higher than available temperature at terrestrial automotive applications. Hence the key research interests are focused towards effective utilization of thermionic energy conversion for automotive waste heat recovery at considerably lower temperatures i.e. <10000C. This strongly needs a selection of suitable materials in thermionic convertor. This work shows a comprehensive study on materials and their work function for thermionic emission at relatively lower temperature. The selection of different emitter materials is based on simulation applying Richardson Dushman equation and child’s law at operating temperature ranges. The
Kodihal, Kantaprasad, Sagar, Ankur
Textile Cools or Insulates AutomaticallyTBMG-3491508/01/2019
Researchers have created a fabric that automatically regulates the amount of heat that passes through, depending on conditions; for example, when conditions are warm and moist — such as those of a sweating body on a summer day — the fabric allows infrared radiation (radiant heat) to pass through. When conditions become cooler and drier, the fabric reduces the heat that escapes. Infrared radiation is a primary way the body releases heat and is the focus of this new technology.
Imaging System Helps Surgeons Remove Tiny Ovarian TumorsTBMG-3456906/01/2019
Ovarian cancer is usually diagnosed only after it has reached an advanced stage, with many tumors spread throughout the abdomen. Most patients undergo surgery to remove as many of these tumors as possible, but because some are so small and widespread, it is difficult to eradicate all of them.
Stretchable, Rubbery SemiconductorsTBMG-3463406/01/2019
Researchers have created stretchable, rubbery semiconductors including rubbery integrated electronics, logic circuits, and arrayed sensory skins fully based on rubber materials. The semiconductors have instilled mechanical stretchability, much like a rubber band.
Q&A: Dr. Mahmooda Sultana, Multifunctional Sensor Researcher/Engineer at NASA GoddardTBMG-3440505/01/2019
Dr. Sultana won funding to advance a nanomaterial-based detector platform that can sense environmental parameters from minute concentrations of target gases and vapors, to atmospheric pressure and temperature, and then transmit that data via a wireless antenna — all from the same 3 × 5’’ self-contained platform.
Individual Quantum Dots Imaged in 3-D for the First TimeTBMG-3389603/01/2019
Researchers have developed an imaging technique that uses a tiny, super sharp needle to nudge a single nanoparticle into different orientations and capture 2-D images to help reconstruct a 3-D picture. The method demonstrates imaging of individual nanoparticles at different orientations while in a laser-induced excited state.
Film Blocks Electromagnetic InterferenceTBMG-3370002/01/2019
Electromagnetic interference (EMI) can harm smartphones, tablets, chips, drones, wearables, aircraft, and human health. EMI is increasing with the explosive proliferation of devices that generate it. A technique was developed to produce relatively low-cost EMI-blocking composite films.
Control of the Diameter and Chiral Angle Distributions During Production of Single-Wall Carbon NanotubesTBMG-3360101/01/2019
Pulsed laser vaporization (PLV) production of single-wall carbon nanotubes (SWNTs) on traditional Co/Ni catalyst was explored with respect to variations in the production temperature. The Rh/Pd results were also reproduced for comparison. The nanotube-type populations were measured via photoluminescence (PL), UV-Vis-NIR (ultraviolet-visible-near-infrared) absorption, and Raman spectroscopy. A small reduction in the average nanotube diameter at lowered production temperature has long been known to occur; however, temperature effect on nanotube population (and not just for diameters) has never been explored.
Thermochromic Windows Convert Sunlight into ElectricityTBMG-3341512/01/2018
Relying on advanced materials such as perovskites and single-walled carbon nano-tubes, a window technology was developed that responds to heat by transforming from transparent to tinted. As the window darkens, it generates electricity. The color change is driven by molecules (methylamine) that are reversibly absorbed into the device. When solar energy heats up the device, the molecules are driven out, and the device is darkened. When the Sun is not shining, the device is cooled back down, and the molecules re-absorb into the window device, which then appears transparent.
One-Dimensional Material with High Current DensityTBMG-3323511/01/2018
Current density is the amount of electrical current per cross-sectional area at a given point. As transistors in integrated circuits become smaller and smaller, they need higher and higher current densities to perform at the desired level. Most conventional electrical conductors, such as copper, tend to break due to overheating or other factors at high current densities, presenting a barrier to creating increasingly small components.
Technique Creates Adaptive MaterialsTBMG-3309710/01/2018
A technique that enables on-demand control of composite behavior could enable a variety of new capabilities for future rotorcraft design, performance, and maintenance. The focus of the research was on controlling how molecules interact with each other; specifically, having them interact in such a way that changes at a small size, or nanoscale, could lead to observed changes at a larger size, or macroscale.
Electric double layer capacitors prepared with polyvinyl alcohol and multi-walled carbon nanotubes2018-36-031309/03/2018
Portable electronics, wearables, electric vehicles and solar cells are sectors in increasingly development which include innovation and miniaturization of the devices. In this scenario, the development of smaller and lightweight energy storage devices, which store more energy, is required. Besides, it is desirable for these devices to be environmentally friendly to minimize pollution. In an attempt to meet these requirements, this work purposes the development and the characterization of nanofibers-based electrode composed of Polyvinyl alcohol (PVA) and multi-walled carbon nanotubes (MWCNT) for electric double layer capacitors (ELCDs) devices with aqueous electrolyte. This composite has been prepared by electrospinning technique and consolidate an electrical conductive and high-surface material electrode. After that, the PVA/MWCNT electrode was assembled in coin cell device with Sodium Sulfate (Na2SO4) electrolyte for electrochemical characterization. The characterization results
Real, Carla Giselle Martins, Vicentini, Rafael, Nunes, Willian Gonçalves, Boas, Otávio Vilas, Costa, Lenon Henrique, Soares, Davi Marcelo, Zanin, Hudson
Faster, More Efficient Information ProcessingTBMG-3286009/01/2018
For decades, computer chips have been shrinking thanks to a steady stream of technological improvements in processing density. Experts have, however, been warning that we'll soon reach the end of the trend known as Moore's Law, in which the number of transistors per square inch on integrated circuits doubles every year. In order to continue improving chip performance, either the material the transistors are made of — from silicon, to carbon nanotubes or graphene — or how current materials store and process information would need to change.
An Analytical Study of Buckling Behavior of Nanocomposite Beams2018-28-005007/09/2018
The structural members like beams are often subjected a mode of sudden failure due to high compressive load which is characterised as buckling. The buckling behaviour is one of the most important parameters needs to be considered while designing the structural members like beams. The polymer composites are the one of the most emerging materials used in air craft structural applications. This paper studies the buckling behaviour of Carbon Nanotube (CNT) reinforced polymer composite beams by using Classical Laminate Plate Theory (CLPT) approach. The elastic constants obtained for the CNT reinforced polymer composite by applying Mori-Tanaka method are further used to analyse the effect of stacking sequence, CNT Volume fraction in the composite, and CNT radii on the critical buckling loads of an eight layered nanocomposite beam. The Numerical results are also presented and compared for various boundary conditions of beams like clamped-clamped and hinged-hinged. The main intention behind
Peyyala, Pramod Kumar, Baddepudi, Malathi, Subba Rao, V. Venkata
Nano-Fiber Filters for Automotive Applications2018-28-004107/09/2018
Engines have well lubricated metallic moving parts protected by oil films. Microscopic airborne particles can easily break down the oil film and change the tight working tolerances of operating components of an engine. In addition to the above requirement, a modern diesel engine requires a highly precise injection system to meet stringent emission norms and it requires an average of 15,000 L of air per unit fuel consumed. Meticulous filtration is key to ensure purity of air and fuel available to engine. A Polyacrylonitrile based nanofiber synthesized using electro-spinning process is an alternative to conventional cellulose media filters. A Scanning Electron Microscope image is analyzed to obtain the fiber diameter and a 2-D modeling is done using this image data. The trend of developing miniaturized model in filtration application and analysis using computational fluid dynamics has limited research till now. The objectives of the paper are to analyze variation of pressure drop and
Malviya, Rajat Malviya
Theoretical Analysis of High Thermal Conductivity Polymer Composite Fin Based Automotive Radiator under Forced Convection2018-28-009907/09/2018
Though high thermal conductivity polymer composites are prepared based on the thermal requirements, the effectiveness and overall heat transfer performance of the radiators have to be addressed comprehensively to validate the concerned efforts taken to prepare the high thermal conductivity polymer composites. In this article, theoretical analysis on the thermal performance of the cross flow type heat exchanger under convection is performed only by concentrating on the term thermal conductivity of the material. Micro channel based geometry is extracted from the given heat exchanger problem to reduce the complexities of simulation. The term cooling system performance index (CSPI) is used to achieve the expected targets in the present investigation. For shorter fins, the effect of thermal conductivity on the cooling system performance index under lower Reynolds number is insignificant. Further discussions on effect of thermal conductivity on various cases are presented with brief
Vadivelu, M A, Ramesh Kumar, C, Naiju, C D
Carbon Fiber/Epoxy Mold with Embedded Carbon Fiber Resistor Heater - Case Study05-11-02-001104/07/2018
The article presents a complete description of the design and manufacturing of a Carbon Fiber/epoxy mold with an embedded Carbon Fiber resistor heater, and the mold performances in terms of its surface temperature distribution and thermal deformations resulting from the heating. The mold was designed for manufacturing aileron skins from Vacuum Bag Only prepreg cured at 135°C. The glass transition temperature of the used resin-hardener system was about 175°C. To ensure homogenous temperature of the mold working surface in the course of curing, the Carbon Fiber heater was embedded in a layer of a highly heat-conductive cristobalite/epoxy composite, forming the core of the mold shell. Because the cristobalite/epoxy composite displayed much higher thermal expansion than CF/epoxy did, thermal stresses could arise due to this discrepancy in the course of heating. Therefore, to lower these stresses, the Carbon Fiber/epoxy faces were separated from the cristobalite/epoxy core containing the
Czarnocki, Piotr, Boczkowska, Anna, Frączek, Wojciech, Chabera, Paulina, Kubis, Michał, Marjanowski, Jędrzej
Biosensor Could Monitor Glucose Levels in Tears and SweatTBMG-2852203/01/2018
Constantly tracking a person's glucose levels through their tears or sweat could be one step closer to providing people with diabetes an improved monitoring tool. Researchers report in the journal ACS Nano the development of an ultra-thin, flexible sensor that could be incorporated into contact lenses or on the backs of watches for real-time glucose tracking.
Advanced Carbon Aerogels for Energy ApplicationsTBMG-2830202/01/2018
Carbon aerogels (CAs) are nano-porous carbons comprising a particularly significant class of carbon nano-materials for a variety of sustainable energy applications. Carbon aerogels are specifically promising in that they possess a tunable, three-dimensional, hierarchical morphology with ultrafine cell size and an electrically conductive framework. They are available as macroscopic, centimeter-sized monolithic materials. Carbon aerogels hold great technological promise for a variety of sustainable energy applications including hydrogen and electrical energy storage, desalination, and electrocatalysis.
Optical Ultrasound Needle for Heart SurgeryTBMG-2816101/01/2018
Doctors currently rely on external ultrasound probes, combined with pre-operative imaging scans, to visualize soft tissue and organs during minimally invasive procedures, as the miniature surgical instruments used do not support internal ultrasound imaging.
Bulk Preparation of Holey Graphene via Controlled Catalytic OxidationTBMG-2817301/01/2018
Researchers at NASA have developed new methods to manufacture carbon materials (e.g., nanotubes, graphene) with holes through the graphitic surface of the particles. The methods generate materials with increased accessible surface area, increased functional groups at damage sites, and improved through-surface molecular transport properties. The materials generated using these techniques are anticipated to be applicable to a variety of industries, especially energy storage (e.g. supercapacitors and batteries) and separation membranes (e.g. for gas, ions, organics, proteins, etc.).
Products of Tomorrow: January 2018TBMG-2818201/01/2018
This column presents technologies that have applications in commercial areas, possibly creating the products of tomorrow. To learn more about each technology, see the contact information provided for that innovation.
High Temperature Graphene-Peek AdhesiveTBMG-2795312/01/2017
Joining of composites can be a challenging issue. If adhesives are used, the joints are permanent and cannot be undone. If they need to be undone, inserts are often used and these inserts increase cost and weight. Additionally, fibers can be cut in the process leading to a part with weakened mechanical properties.
Soft Robotic Gripper Manipulates Objects Without TrainingTBMG-2794412/01/2017
An engineering team at the University of California San Diego has designed and built a gripper that can pick up and manipulate objects without needing to see them and without being trained. The gripper is unique because it brings together three different capabilities; it can twist objects, it can sense objects, and it can build models of the objects it’s manipulating. This allows the gripper to operate in low light and low-visibility conditions, for example.
High Temperature Graphene-Peek Adhesive17AERP12_0912/01/2017
Compounding graphene into polymers has the potential to improve various material properties, even at very low concentrations. Armament Research, Development and Engineering Center, Watervliet, New York Joining of composites can be a challenging issue. If adhesives are used, the joints are permanent and cannot be undone. If they need to be undone, inserts are often used and these inserts increase cost and weight. Additionally, fibers can be cut in the process leading to a part with weakened mechanical properties. Even with these drawbacks, most components that need to be joined are threaded together, allowing for removal of the parts at a later time. However, threaded connections are costly to design and manufacture, and are often the location of fatigue failures due to their inherent stress concentrations. From an environmental and cost standpoint, there is a large waste associated with the removal of material to form the threads, even more so in sectored threads, where up to half of
Stronger Silk Offers Biomedical ApplicationsTBMG-2790711/15/2017
Engineers have found they can make a material that is more than twice as stiff as its natural counterpart and can be shaped into complex structures such as meshes and lattices.
Effects of Reflux Temperature and Molarity of Acidic Solution on Chemical Functionalization of Helical Carbon Nanotubes05-11-01-000409/19/2017
The use of nanomaterials and nanostructures have been revolutionizing the advancements of science and technology in various engineering and medical fields. As an example, Carbon Nanotubes (CNTs) have been extensively used for the improvement of mechanical, thermal, electrical, magnetic, and deteriorative properties of traditional composite materials for applications in high-performance structures. The exceptional materials properties of CNTs (i.e., mechanical, magnetic, thermal, and electrical) have introduced them as promising candidates for reinforcement of traditional composites. Most structural configurations of CNTs provide superior material properties; however, their geometrical shapes can deliver different features and characteristics. As one of the unique geometrical configurations, helical CNTs have a great potential for improvement of mechanical, thermal, and electrical properties of polymeric resin composites. The coil spring shape of these CNTs give them the capability to
Taklimi, Sean, Ghazinezami, Ali, Cluff PhD, Kim, Askari, Davood
3D Chip Combines Computing and Data StorageTBMG-2754709/01/2017
Fields ranging from autonomous driving to personalized medicine are generating huge amounts of data. But just as the flood of data is reaching massive proportions, the ability of computer chips to process it into useful information is stalling.
Resistive Heating-Assisted Infiltration and Cure (RHAIC) for Polymer/Carbon Nanotube Structural CompositesTBMG-2754609/01/2017
NASA’s Langley Research Center scientists have developed a process for fabricating carbon nanotube (CNT) structural nanocomposites that brings CNT-based composites closer to realizing their potential for structural applications. Conventional methods fail to properly wet CNTs within the epoxy matrix due to high resin viscosity, resulting in poor infiltration and reduced load transfer between the CNTs and matrix. The NASA process — resistive heating-assisted epoxy infiltration (RHAEI) — uses the CNTs’ electrical resistance to generate heat, which reduces epoxy resin viscosity for greater CNT wetting and adhesion. Mechanical properties are significantly improved compared to conventional methods. NASA’s process has been demonstrated to offer 50% improvement in strength and elastic modulus, with mechanical properties competitive with structural carbon fiber composites.
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