Tech Briefs

Self-Protected, Low-Temperature Nanosolder

The nanosolder is inexpensive and easy to use in an assembly process.

Nanosolders allow for increased capabilities in the formation of soldered interconnections for heat-sensitive electronic packages. The desired characteristic of nanosolder is to have a low process temperature that does not damage base materials or components, while also having a high service temperature that allows the product to operate in harsh environments.

Posted in: Briefs, Materials, Electronic equipment, Microelectricmechanical device, Microelectromechanical devices, Electronic equipment, Microelectricmechanical device, Microelectromechanical devices, Copper alloys, Materials properties, Nanomaterials

Resistive Heating-Assisted Infiltration and Cure (RHAIC) for Polymer/Carbon Nanotube Structural Composites

This process can be used for airframe components, lightweight construction structures, thermal management, and electromagnetic shielding for cars.

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.

Posted in: Briefs, Materials, Composite materials, Nanomaterials, Polymers, Resins

3D Chip Combines Computing and Data Storage

Memory cells and carbon nanotubes are built vertically over one another, making a 3D computer architecture with interleaving layers of logic and memory.

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.

Posted in: Briefs, Electronics & Computers, Architecture, Computer software / hardware, Computer software and hardware, Integrated circuits, Architecture, Computer software / hardware, Computer software and hardware, Integrated circuits, Data management, Product development

Rotary Piston Engine

There are many applications where a high power-to-weight engine is either necessary or helpful. Uses for this type of engine range from handheld power equipment, to motorcycles and aircraft — uses multiply when fuel efficiency, compactness, and versatility are added. Currently, there are few viable options available to fulfill these applications, and those that are available are very inefficient when high power is no longer desired. When the application warrants it, the engine type of choice has been the turbine engine.

Posted in: Briefs, Propulsion, Technical reference, Technical review, Engine efficiency, Pistons, Rotary engines

Green Liquid Monopropellant Thruster for In-Space Propulsion

Hydrazine has been the standard baseline liquid monopropellant for space propulsion over many decades since replacing hydrogen peroxide. Hydrazine was preferred over peroxide due to its easier storability and higher performance. Like peroxide, hydrazine can be readily decomposed by passing it over a catalyst. For these advantages, hydrazine has a significant drawback: it is toxic (carcinogen and mutagen), and its handling and refurbishment requires special procedures. Accidental spill is a concern, and strict and expensive mitigation procedures are required. In recent years, a need has arisen to find green or reduced toxicity hydrazine substitutes with equal or greater propulsive performance than hydrazine.

Posted in: Briefs, Propulsion, Alternative fuels, Hydrazines, Liquid propellants, Research and development, Fuel injection, Spacecraft

Shaper Design in CMOS for High Dynamic Range

This circuit design has uses in industrial automation, medical signal processing, and radiation detection for medical and security applications.

Front-end electronics for capacitive sensors typically include a preamplifier followed by a filter. The preamplifier provides low-noise amplification of the signals induced in the sensor electrodes. The filter, by properly limiting the signal bandwidth, maximizes the Signal-to-Noise (S/N) ratio. Additionally, the filter limits the duration of the output signal associated with the measured event and, for those sensors where the induced signal is relatively slow, it maximizes the signal amplitude.

Posted in: Briefs, Electronics & Computers, Design processes, Amplifiers, Electronic equipment, Sensors and actuators, Amplifiers, Electronic equipment, Sensors and actuators, Noise, Noise

Tamper-Indicating Bolt

This system detects whether tampering has occurred in a container or compartment during storage or transport.

In storage and/or transport of certain items, the ability to detect tampering with a container or compartment for such items can be necessary and valuable. In the transport of hazardous substances or nuclear materials (including fuels and/or radioactive waste), there are particularly stringent requirements to ensure integrity as well as safe transport and storage of materials. A retailer shipping inventory may need to know whether tampering with the container has occurred during transport to determine if shipment is original and complete.

Posted in: Briefs, Mechanical Components, Logistics, Containers, Packaging, Fasteners, Quality control, Quality control, Safety testing and procedures

NetEgg: Automated Code Generation for Software-Defined Networks

This software enables fast and easy network configuration.

Software-Defined Networking (SDN) usually requires network administrators to be skilled in programming languages such as C++, Python, or Ruby. Many IT operators tasked with installing routers or other network components may lack the skills to program SDN equipment. Due to a shortage of trained staff, implementing SDN across an entire enterprise can become very time-consuming and costly.

Posted in: Briefs, Software, Computer software / hardware, Computer software and hardware, Computer software / hardware, Computer software and hardware, Human factors, Education, Education and training, Automation, Productivity

Robust Method for Data Protection and Change Detection

Methods exist for processing an original data sequence in order to generate information about the data for the purposes of integrity measurement, ownership demonstration, and authentication. The first category is digital watermarking, the second is data hashing, and the third is error detection coding. In the present context, watermarking is often used for ownership demonstration and authentication purposes; data hashing is often used for integrity measurement purposes; and as with data hashing, error detection coding is used to measure data integrity. However, the latter is normally done as part of data transmission protocol, and therefore addresses transmission errors rather than tampering.

Posted in: Briefs, Software, Finite element analysis, Computer software / hardware, Computer software and hardware, Cyber security, Computer software / hardware, Computer software and hardware, Cyber security, Data management, Identification

X-Ray Scattering Constructs 3D Images of Nanoparticle Grains

Scientists at Argonne National Laboratory have developed a new X-ray technique to see inside continuously packed nanoparticles, also known as grains, to examine deformations and dislocations that affect their properties.

Posted in: Briefs, Photonics

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