Materials & Coatings

Straight-Pore Microfilter With Efficient Regeneration

A novel, high-efficiency gas particulate filter has precise particle size screening, low pressure drop, and a simple and fast regeneration process. The regeneration process, which requires minimal material and energy consumption, can be completely automated, and the filtration performance can be restored within a very short period of time.

Posted in: Briefs, TSP, Materials, Maintenance, Repair and Service Operations, Maintenance, repair, and service operations, Particulate filters

Determining Shear Stress Distribution in a Laminate

The simplified shear solution does not require solution of a particular boundary value problem.

A “simplified shear solution” method approximates the through-thickness shear stress distribution within a composite laminate based on an extension of laminated beam theory. The method does not consider the solution of a particular boundary value problem; rather, it requires only knowledge of the global shear loading, geometry, and material properties of the laminate or panel. It is thus analogous to lamination theory in that ply-level stresses can be efficiently determined from global load resultants at a given location in a structure and used to evaluate the margin of safety on a ply-by-ply basis. The simplified shear solution stress distribution is zero at free surfaces, continuous at ply boundaries, and integrates to the applied shear load. The method has been incorporated within the HyperSizer® commercial structural sizing software to improve its predictive capability for designing composite structures.

Posted in: Briefs, TSP, Materials, Composite materials, Materials properties, Durability, Durability, Test procedures

InGaP Heterojunction Barrier Solar Cells

Nanostructured cells could enhance the performance of terrestrial high-efficiency solar cells.

A new solar-cell structure utilizes a single, ultra-wide well of either gallium arsenide (GaAs) or indium-galliumphosphide (InGaP) in the depletion region of a wide bandgap matrix, instead of the usual multiple quantum well layers. These InGaP barrier layers are effective at reducing diode dark current, and photogenerated carrier escape is maximized by the proper design of the electric field and barrier profile. With the new material, open-circuit voltage enhancements of 40 and 100 mV (versus PIN control systems) are possible without any degradation in short-circuit current.

Posted in: Briefs, TSP, Materials, Solar energy, Alloys, Materials properties

Low-Outgassing Adhesives

Applications include solar panels, LEDs, and medical devices.

Products and manufacturing processes can be sensitive to outgassed chemical compounds, resulting in the use of adhesives, encapsulants, and sealants that have been specially formulated for low-outgassing performance. The most stringent outgassing requirements are best met by products formulated to pass an industry-standard outgassing test known as ASTM E595-07. Low-outgassing adhesives don’t typically require any sacrifice in other mechanical or physical properties. What sets low-outgassing products apart from their generic counterparts is that the low-outgassing grades have passed the ASTM test.

Posted in: Briefs, Materials, Adhesives and sealants, Chemicals, Gases, Materials properties

Functionalization of Single-Wall Carbon Nanotubes by Photo-Oxidation

A new technique for carbon nanotube oxidation was developed based upon the photo-oxidation of organic compounds. The resulting method is more benign than conventional oxidation approaches and produces single-wall carbon nanotubes (SWCNTs) with higher levels of oxidation.

Posted in: Briefs, TSP, Materials, Chemicals, Nanotechnology, Oxygen

Ultra-High-Molecular-Weight Polyethylene Technology for Minimally Invasive Devices

Ultra-thin film and fiber are suitable for implantable cardiovascular devices.

Ultra-high-molecular-weight polyethylene (UHMWPE) has been used for decades as a biomaterial in joint replacements. Recently, this technology was refined to serve the needs of minimally invasive surgical applications, particularly cardiovascular implants. UHMWPE fiber can be shaped into a range of textile constructions, including braids and woven tubes, while the film can be used as a very thin barrier or cover. As such, the medical-grade UHMWPE film and fiber are suitable for enhancing the design of various implantable cardiovascular devices, including stent grafts and covered stents.

Posted in: Briefs, MDB, Briefs, Coatings & Adhesives, Materials, Bio-Medical, Implants & Prosthetics, Medical, Cardiovascular system, Prostheses and implants, Fibers, Polymers

Modifying Polyethylene Oxide for Melt-Processability

Water-soluble packaging, disposable articles, and transdermal patches are possible applications for products made using water-soluble PEO.

Generally, high-molecular-weight polyethylene oxide (PEO) can present processing challenges due to its high melt viscosity and poor melt drawability; it can be difficult to form into fine-gauge film or small-diameter fibers. There is the alternative technology of solution casting, which has occasionally been utilized to cast thin films; however, solution casting may not always be practical for large-scale, economically viable film production.

Posted in: Briefs, MDB, Briefs, Coatings & Adhesives, Materials, Bio-Medical, Medical, Casting, Materials properties, Resins

Topical Compositions and Glove for Protection and Shielding Against Radiation Exposure

These technologies have applications in military, nuclear energy, and emergency preparedness.

Over the past several decades, there has been a proliferation of medical diagnostic and treatment devices that involve the use of X-rays, beta rays, gamma rays, and radioactive isotopes. In addition, there has been recent concern regarding possible radiation exposure from nuclear weapons and terrorist attacks on nuclear facilities. Thus, there is a need for devices that can protect areas of the body that may be exposed to damaging radiation without hindering the user’s dexterity or loss of touch sensation.

Posted in: Briefs, MDB, Briefs, Coatings & Adhesives, Materials, Bio-Medical, Medical, Patient Monitoring, Medical equipment and supplies, Protective clothing, Radiation protection

Digital Microfluidics Sample Analyzer

Combined innovations enable portable analyzers for medical diagnostics, bioterrorism pathogen detection, and food supply analysis.

Three innovations address the needs of the medical world with regard to microfluidic manipulation and testing of physiological samples in ways that can benefit point-of-care needs for patients such as premature infants, for which drawing of blood for continuous tests can be life-threatening in their own right, and for expedited results. A chip with sample injection elements, reservoirs (and waste), droplet formation structures, fluidic pathways, mixing areas, and optical detection sites, was fabricated to test the various components of the microfluidic platform, both individually and in integrated fashion. The droplet control system permits a user to control droplet microactuator system functions, such as droplet operations and detector operations. Also, the programming system allows a user to develop software routines for controlling droplet microactuator system functions, such as droplet operations and detector operations.

Posted in: Briefs, MDB, Briefs, Coatings & Adhesives, Materials, Bio-Medical, Diagnostics, Medical, Patient Monitoring, Software, Microelectricmechanical device, Microelectromechanical devices, Sensors and actuators, Microelectricmechanical device, Microelectromechanical devices, Sensors and actuators, Diagnosis, Medical equipment and supplies, Product development, Test equipment and instrumentation

Magnesium Diboride Current Leads

The superconductor can be applied to cryogenic wiring.

A recently discovered superconductor, magnesium diboride (MgB2), can be used to fabricate conducting leads used in cryogenic applications. Discovered to be superconducting in 2001, MgB2 has the advantage of remaining superconducting at higher temperatures than the previously used material, NbTi. The purpose of these leads is to provide 2 A of electricity to motors located in a 1.3 K environment. The providing environment is a relatively warm 17 K. Requirements for these leads are to survive temperature fluctuations in the 5 K and 11 K heat sinks, and not conduct excessive heat into the 1.3 K environment. Test data showed that each lead in the assembly could conduct 5 A at 4 K, which, when scaled to 17 K, still provided more than the required 2 A.

Posted in: Briefs, Materials, Electric cables, Electric cables, Thermal management, Thermal management, Fabrication, Conductivity, Magnesium, Electric motors

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