Method and system for automated on-chip material and structural certification of MEMS devices

DOEpatents

Sinclair, Michael B.; DeBoer, Maarten P.; Smith, Norman F.; Jensen, Brian D.; Miller, Samuel L.

2003-05-20

A new approach toward MEMS quality control and materials characterization is provided by a combined test structure measurement and mechanical response modeling approach. Simple test structures are cofabricated with the MEMS devices being produced. These test structures are designed to isolate certain types of physical response, so that measurement of their behavior under applied stress can be easily interpreted as quality control and material properties information.

Active Control Technology at NASA Langley Research Center

NASA Technical Reports Server (NTRS)

Antcliff, Richard R.; McGowan, Anna-Marie R.

2000-01-01

NASA Langley has a long history of attacking important technical Opportunities from a broad base of supporting disciplines. The research and development at Langley in this subject area range from the test tube to the test flight, The information covered here will range from the development of innovative new materials, sensors and actuators, to the incorporation of smart sensors and actuators in practical devices, to the optimization of the location of these devices, to, finally, a wide variety of applications of these devices utilizing Langley's facilities and expertise. Advanced materials are being developed for sensors and actuators, as well as polymers for integrating smart devices into composite structures. Contributions reside in three key areas: computational materials; advanced piezoelectric materials; and integrated composite structures.

Future opportunities for advancing glucose test device electronics.

PubMed

Young, Brian R; Young, Teresa L; Joyce, Margaret K; Kennedy, Spencer I; Atashbar, Massood Z

2011-09-01

Advancements in the field of printed electronics can be applied to the field of diabetes testing. A brief history and some new developments in printed electronics components applicable to personal test devices, including circuitry, batteries, transmission devices, displays, and sensors, are presented. Low-cost, thin, and lightweight materials containing printed circuits with energy storage or harvest capability and reactive/display centers, made using new printing/imaging technologies, are ideal for incorporation into personal-use medical devices such as glucose test meters. Semicontinuous rotogravure printing, which utilizes flexible substrates and polymeric, metallic, and/or nano "ink" composite materials to effect rapidly produced, lower-cost printed electronics, is showing promise. Continuing research advancing substrate, "ink," and continuous processing development presents the opportunity for research collaboration with medical device designers. © 2011 Diabetes Technology Society.

Investigation of Basic Mechanisms of Radiation Effects in Carbon-Based Electronic Materials

DTIC Science & Technology

2017-06-01

materials characterization, and carbon nanotube diodes, FET, and PZT-memory test device structures for electrical measurements. Pre - and post -irradiation...definition (Radiation exposure) Task 2) The grantee shall perform testing to include: - Radiation testing . May be multiple types. - Pre and post -rad...technologies for electronic devices. Experiential radiation testing has included exposure to 10 keV X-rays, 4 MeV protons, heavy ions, and Ultra

Dentin barrier test with transfected bovine pulp-derived cells.

PubMed

Schmalz, G; Schuster, U; Thonemann, B; Barth, M; Esterbauer, S

2001-02-01

Growth kinetics of SV40 large T-antigen-transfected bovine pulp-derived cells on dentin were investigated. These cells were used in a dentin barrier test device, and the system was evaluated by testing a set of dental filling materials. Cells (120 cells/mm2) were seeded on dentin slices and incubated for up to 21 days. Cell proliferation was recorded using MTT assay. For cytotoxicity tests 3500 cells/mm2 were seeded on dentin discs, which were then incorporated into the dentin barrier test device. After 72 h preincubation test materials were applied. After a 24 h exposure with or without perfusion of the pulpal part of the test device, cell survival was evaluated using MTT assay. The cells revealed similar growth kinetics on dentin slices and on tissue culture plates. In cytotoxicity tests the cells were more sensitive toward the test materials than previously used three-dimensional cultures of human foreskin fibroblasts and as anticipated from clinical experience. Further improvement is expected by using three-dimensional cultures of pulp-derived cells.

21 CFR 862.3280 - Clinical toxicology control material.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Clinical toxicology control material. 862.3280... (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Toxicology Test Systems § 862.3280 Clinical toxicology control material. (a) Identification. A clinical toxicology control...

21 CFR 862.3280 - Clinical toxicology control material.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Clinical toxicology control material. 862.3280... (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Toxicology Test Systems § 862.3280 Clinical toxicology control material. (a) Identification. A clinical toxicology control...

21 CFR 862.3280 - Clinical toxicology control material.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Clinical toxicology control material. 862.3280... (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Toxicology Test Systems § 862.3280 Clinical toxicology control material. (a) Identification. A clinical toxicology control...

21 CFR 862.3280 - Clinical toxicology control material.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Clinical toxicology control material. 862.3280... (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Toxicology Test Systems § 862.3280 Clinical toxicology control material. (a) Identification. A clinical toxicology control...

21 CFR 862.3280 - Clinical toxicology control material.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Clinical toxicology control material. 862.3280... (CONTINUED) MEDICAL DEVICES CLINICAL CHEMISTRY AND CLINICAL TOXICOLOGY DEVICES Clinical Toxicology Test Systems § 862.3280 Clinical toxicology control material. (a) Identification. A clinical toxicology control...

Long term thermoelectric module testing system.

PubMed

D'Angelo, Jonathan; Hogan, Timothy

2009-10-01

Thermoelectric generators can be used for converting waste heat into electric power. Significant interest in developing new materials in recent years has led to the discovery of several promising thermoelectrics, however, there can be considerable challenges in developing the materials into working devices. Testing and feedback is needed at each step to gain valuable information for identification of difficulties, quality of the materials and modules, repeatability in fabrication, and longevity of the devices. This paper describes a long-term module testing system for monitoring the output power of a module over extended testing times. To evaluate the system, we have tested commercially available thermoelectric modules over a one month time period.

Biological Evaluation of the Copper/Low-density Polyethylene Nanocomposite Intrauterine Device

PubMed Central

Wang, Hong; Li, Jun; Xie, Changsheng; Duan, Zhuo; Sun, Li-Kui; Wang, Xin; Zhu, Changhong

2013-01-01

Devices and materials intended for clinical applications as medical and implant devices should be evaluated to determine their biocompatibility in physiological systems. This article presents results from cytotoxicity assay of L929 mouse fibroblasts culture, tests for skin irritation, intracutaneous reactivity and sensitization, and material implantation tests for the novel copper/low-density polyethylene nanocomposite intrauterine device (nano-Cu/LDPE IUD) with potential for future clinical utilization. Cytotoxicity test in vitro was conducted to evaluate the change in morphology, growth and proliferation of cultured L929 mouse fibroblasts, which in vivo examination for skin irritation (n = 6) and intracutaneous reactivity (n = 6) were carried out to explore the irritant behavior in New Zealand White rabbits. Skin sensitization was implemented to evaluate the potential skin sensitizing in Hartley guinea pigs (n = 35). The materials were implanted into the spinal muscle of rabbits (n = 9). The cytotoxicity grade of the nano-Cu/LDPE IUD was 0–1, suggested that the composite was nontoxic or mildly cytotoxic; no irritation reaction and skin sensitization were identified in any animals of specific extracts prepared from the material under test; similarly to the control sides, the inflammatory reaction was observed in the rabbits living tissue of the implanted material in intramuscular implantation assay. They indicated that the novel composite intrauterine device presented potential for this type of application because they meet the requirements of the standard practices recommended for evaluating the biological reactivity. The nano-Cu/LDPE IUD has good biocompatibility, which is biologically safe for the clinical research as a novel contraceptive device. PMID:24058521

Biological evaluation of the copper/low-density polyethylene nanocomposite intrauterine device.

PubMed

Hu, Li-Xia; He, Jing; Hou, Li; Wang, Hong; Li, Jun; Xie, Changsheng; Duan, Zhuo; Sun, Li-Kui; Wang, Xin; Zhu, Changhong

2013-01-01

Devices and materials intended for clinical applications as medical and implant devices should be evaluated to determine their biocompatibility in physiological systems. This article presents results from cytotoxicity assay of L929 mouse fibroblasts culture, tests for skin irritation, intracutaneous reactivity and sensitization, and material implantation tests for the novel copper/low-density polyethylene nanocomposite intrauterine device (nano-Cu/LDPE IUD) with potential for future clinical utilization. Cytotoxicity test in vitro was conducted to evaluate the change in morphology, growth and proliferation of cultured L929 mouse fibroblasts, which in vivo examination for skin irritation (n = 6) and intracutaneous reactivity (n = 6) were carried out to explore the irritant behavior in New Zealand White rabbits. Skin sensitization was implemented to evaluate the potential skin sensitizing in Hartley guinea pigs (n = 35). The materials were implanted into the spinal muscle of rabbits (n = 9). The cytotoxicity grade of the nano-Cu/LDPE IUD was 0-1, suggested that the composite was nontoxic or mildly cytotoxic; no irritation reaction and skin sensitization were identified in any animals of specific extracts prepared from the material under test; similarly to the control sides, the inflammatory reaction was observed in the rabbits living tissue of the implanted material in intramuscular implantation assay. They indicated that the novel composite intrauterine device presented potential for this type of application because they meet the requirements of the standard practices recommended for evaluating the biological reactivity. The nano-Cu/LDPE IUD has good biocompatibility, which is biologically safe for the clinical research as a novel contraceptive device.

Dynamic MEMS devices for multi-axial fatigue and elastic modulus measurement

NASA Astrophysics Data System (ADS)

White, Carolyn D.; Xu, Rui; Sun, Xiaotian; Komvopoulos, Kyriakos

2003-01-01

For reliable MEMS device fabrication and operation, there is a continued demand for precise characterization of materials at the micron scale. This paper presents a novel material characterization device for fatigue lifetime testing. The fatigue specimen is subjected to multi-axial loading, which is typical of most MEMS devices. Polycrystalline silicon (polysilicon) fatigue devices were fabricated using the MUMPS process with a three layer mask process ground plane, anchor, and structural layer of polysilicon. A fatigue device consists of two or three beams, attached to a rotating ring and anchored to the substrate on each end. In order to generate a sufficiently large stress, the fatigue devices were tested in resonance to produce a von Mises equivalent stress as high as 1 GPa, which is in the fracture strength range reported for polysilicon. A further increase of the stress in the beam specimens was obtained by introducing a notch with a focused ion beam. The notch resulted into a stress concentration factor of about 3.8, thereby producing maximum von Mises equivalent stress in the range of 1 through 4 GPa. This study provides insight into multi-axial fatigue testing under typical MEMS conditions and additional information about micron-scale polysilicon mechanical behavior, which is the current basic building material for MEMS devices.

Finger-attachment device for the feedback of gripping and pulling force in a manipulating system for brain tumor resection.

PubMed

Chinbe, Hiroyuki; Yoneyama, Takeshi; Watanabe, Tetsuyou; Miyashita, Katsuyoshi; Nakada, Mitsutoshi

2018-01-01

Development and evaluation of an effective attachment device for a bilateral brain tumor resection robotic surgery system based on the sensory performance of the human index finger in order to precisely detect gripping- and pulling-force feedback. First, a basic test was conducted to investigate the performance of the human index finger in the gripping- and pulling-force feedback system. Based on the test result, a new finger-attachment device was designed and constructed. Then, discrimination tests were conducted to assess the pulling force and the feedback on the hardness of the gripped material. The results of the basic test show the application of pulling force on the side surface of the finger has an advantage to distinguish the pulling force when the gripping force is applied on the finger-touching surface. Based on this result, a finger-attachment device that applies a gripping force on the finger surface and pulling force on the side surface of the finger was developed. By conducting a discrimination test to assess the hardness of the gripped material, an operator can distinguish whether the gripped material is harder or softer than a normal brain tissue. This will help in confirming whether the gripped material is a tumor. By conducting a discrimination test to assess the pulling force, an operator can distinguish the pulling-force resistance when attempting to pull off the soft material. Pulling-force feedback may help avoid the breaking of blood pipes when they are trapped in the gripper or attached to the gripped tissue. The finger-attachment device that was developed for detecting gripping- and pulling-force feedback may play an important role in the development of future neurosurgery robotic systems for precise and safe resection of brain tumors.

Characterization of deformable materials in the THOR dummy

DOT National Transportation Integrated Search

2000-01-01

Methodologies used to characterize the mechanical behavior of various materials used in the construction of the crash test dummy called THOR (Test device for Human Occupant Restraint) are described. These materials include polyurethane, neoprene, and...

A novel in situ device based on a bionic piezoelectric actuator to study tensile and fatigue properties of bulk materials.

PubMed

Wang, Shupeng; Zhang, Zhihui; Ren, Luquan; Zhao, Hongwei; Liang, Yunhong; Zhu, Bing

2014-06-01

In this work, a miniaturized device based on a bionic piezoelectric actuator was developed to investigate the static tensile and dynamic fatigue properties of bulk materials. The device mainly consists of a bionic stepping piezoelectric actuator based on wedge block clamping, a pair of grippers, and a set of precise signal test system. Tensile and fatigue examinations share a set of driving system and a set of signal test system. In situ tensile and fatigue examinations under scanning electron microscope or metallographic microscope could be carried out due to the miniaturized dimensions of the device. The structure and working principle of the device were discussed and the effects of output difference between two piezoelectric stacks on the device were theoretically analyzed. The tensile and fatigue examinations on ordinary copper were carried out using this device and its feasibility was verified through the comparison tests with a commercial tensile examination instrument.

A novel in situ device based on a bionic piezoelectric actuator to study tensile and fatigue properties of bulk materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Shupeng; Zhang, Zhihui, E-mail: zhzh@jlu.edu.cn; Ren, Luquan

2014-06-15

In this work, a miniaturized device based on a bionic piezoelectric actuator was developed to investigate the static tensile and dynamic fatigue properties of bulk materials. The device mainly consists of a bionic stepping piezoelectric actuator based on wedge block clamping, a pair of grippers, and a set of precise signal test system. Tensile and fatigue examinations share a set of driving system and a set of signal test system. In situ tensile and fatigue examinations under scanning electron microscope or metallographic microscope could be carried out due to the miniaturized dimensions of the device. The structure and working principlemore » of the device were discussed and the effects of output difference between two piezoelectric stacks on the device were theoretically analyzed. The tensile and fatigue examinations on ordinary copper were carried out using this device and its feasibility was verified through the comparison tests with a commercial tensile examination instrument.« less

Implementation of Testing Equipment for Asphalt Materials : Tech Summary

DOT National Transportation Integrated Search

2009-05-01

Three new automated methods for related asphalt material and mixture testing were evaluated under this study. Each of these devices is designed to reduce testing time considerably and reduce operator error by automating the testing process. The Thery...

Implementation of testing equipment for asphalt materials : tech summary.

DOT National Transportation Integrated Search

2009-05-01

Three new automated methods for related asphalt material and mixture testing were evaluated : under this study. Each of these devices is designed to reduce testing time considerably and reduce : operator error by automating the testing process. The T...

40 CFR 65.158 - Performance test procedures for control devices.

Code of Federal Regulations, 2010 CFR

2010-07-01

... regulated material or as TOC (minus methane and ethane) according to the procedures specified. (1) Method 1... material or TOC, sampling sites shall be located at the inlet of the control device as specified in the... sampling sites shall ensure the measurement of total regulated material or TOC (minus methane and ethane...

OHMSETT (Oil and Hazardous Materials Simulated Environmental Test Tank) test series 77: Global Oil Recovery Skimmer, Veegarm Skimming Arm, Kebab 600, Wylie Skimmer and the Skim-Pak Cluster. Final report Jan 80-Jun 81

DOE Office of Scientific and Technical Information (OSTI.GOV)

Borst, M.

1984-03-01

This report covers the performance testing of five oil spill recovery devices at the Oil and Hazardous Materials Simulated Environmental Test Tank in Leonardo, New Jersey. The GOR Skimmer was tow tested in harbor chops, regular waves, and calm water at tow speeds through 2 knots to determine the effectiveness of modifications made to the device since it was last tested. The performance was consistently lower after the modifications in all conditions. The Hydrovac Veegarm was the most exhaustively tested skimmer in this program.

Active Control Technology at NASA Langley Research Center

NASA Technical Reports Server (NTRS)

Antcliff, Richard R.; McGowan, Anna-Marie R.

2000-01-01

NASA Langley has a long history of attacking important technical opportunities from a broad base of supporting disciplines. The research and development at Langley in this subject area range from the test tube to the test flight. The information covered here will range from the development of innovative new materials, sensors and actuators, to the incorporation of smart sensors and actuators in practical devices, to the optimization of the location of these devices, to, finally, a wide variety of applications of these devices utilizing Langley's facilities and expertise. Advanced materials are being developed for sensors and actuators, as well as polymers for integrating smart devices into composite structures. Contributions reside in three key areas: computational materials; advanced piezoelectric materials; and integrated composite structures. The computational materials effort is focused on developing predictive tools for the efficient design of new materials with the appropriate combination of properties for next generation smart airframe systems. Research in the area of advanced piezoelectrics includes optimizing the efficiency, force output, use temperature, and energy transfer between the structure and device for both ceramic and polymeric materials. For structural health monitoring, advanced non-destructive techniques including fiber optics are being developed for detection of delaminations, cracks and environmental deterioration in aircraft structures. The computational materials effort is focused on developing predictive tools for the efficient design of new materials with the appropriate combination of properties for next generation smart airframe system. Innovative fabrication techniques processing structural composites with sensor and actuator integration are being developed.

A sampling device with a capped body and detachable handle

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jezek, Gerd-Rainer

1997-12-01

The present invention relates to a device for sampling radioactive waste and more particularly to a device for sampling radioactive waste which prevents contamination of a sampled material and the environment surrounding the sampled material. During vitrification of nuclear wastes, it is necessary to remove contamination from the surfaces of canisters filled with radioactive glass. After removal of contamination, a sampling device is used to test the surface of the canister. The one piece sampling device currently in use creates a potential for spreading contamination during vitrification operations. During operations, the one piece sampling device is transferred into and outmore » of the vitrification cell through a transfer drawer. Inside the cell, a remote control device handles the sampling device to wipe the surface of the canister. A one piece sampling device can be contaminated by the remote control device prior to use. Further, the sample device can also contaminate the transfer drawer producing false readings for radioactive material. The present invention overcomes this problem by enclosing the sampling pad in a cap. The removable handle is reused which reduces the amount of waste material.« less

Postirradiation thermocyclic loading of ferritic-martensitic structural materials

NASA Astrophysics Data System (ADS)

Belyaeva, L.; Orychtchenko, A.; Petersen, C.; Rybin, V.

Thermonuclear fusion reactors of the Tokamak-type will be unique power engineering plants to operate in thermocyclic mode only. Ferritic-martensitic stainless steels are prime candidate structural materials for test blankets of the ITER fusion reactor. Beyond the radiation damage, thermomechanical cyclic loading is considered as the most detrimental lifetime limiting phenomenon for the above structure. With a Russian and a German facility for thermal fatigue testing of neutron irradiated materials a cooperation has been undertaken. Ampule devices to irradiate specimens for postirradiation thermal fatigue tests have been developed by the Russian partner. The irradiation of these ampule devices loaded with specimens of ferritic-martensitic steels, like the European MANET-II, the Russian 05K12N2M and the Japanese Low Activation Material F82H-mod, in a WWR-M-type reactor just started. A description of the irradiation facility, the qualification of the ampule device and the modification of the German thermal fatigue facility will be presented.

Passive safety device and internal short tested method for energy storage cells and systems

DOEpatents

Keyser, Matthew; Darcy, Eric; Long, Dirk; Pesaran, Ahmad

2015-09-22

A passive safety device for an energy storage cell for positioning between two electrically conductive layers of the energy storage cell. The safety device also comprising a separator and a non-conductive layer. A first electrically conductive material is provided on the non-conductive layer. A first opening is formed through the separator between the first electrically conductive material and one of the electrically conductive layers of the energy storage device. A second electrically conductive material is provided adjacent the first electrically conductive material on the non-conductive layer, wherein a space is formed on the non-conductive layer between the first and second electrically conductive materials. A second opening is formed through the non-conductive layer between the second electrically conductive material and another of the electrically conductive layers of the energy storage device. The first and second electrically conductive materials combine and exit at least partially through the first and second openings to connect the two electrically conductive layers of the energy storage device at a predetermined temperature.

Apparatus for gas sorption measurement with integrated gas composition measurement device and gas mixing

DOEpatents

Micklash. II, Kenneth James; Dutton, Justin James; Kaye, Steven

2014-06-03

An apparatus for testing of multiple material samples includes a gas delivery control system operatively connectable to the multiple material samples and configured to provide gas to the multiple material samples. Both a gas composition measurement device and pressure measurement devices are included in the apparatus. The apparatus includes multiple selectively openable and closable valves and a series of conduits configured to selectively connect the multiple material samples individually to the gas composition device and the pressure measurement devices by operation of the valves. A mixing system is selectively connectable to the series of conduits and is operable to cause forced mixing of the gas within the series of conduits to achieve a predetermined uniformity of gas composition within the series of conduits and passages.

A Mechanomodulatory Device to Minimize Incisional Scar Formation

PubMed Central

Wong, Victor W.; Beasley, Bill; Zepeda, John; Dauskardt, Reinhold H.; Yock, Paul G.; Longaker, Michael T.; Gurtner, Geoffrey C.

2013-01-01

Objective To mechanically control the wound environment and prevent cutaneous scar formation. Approach We subjected various material substrates to biomechanical testing to investigate their ability to modulate skin behavior. Combinations of elastomeric materials, adhesives, and strain applicators were evaluated to develop topical stress-shielding devices. Noninvasive imaging modalities were utilized to characterize anatomic site-specific differences in skin biomechanical properties in humans. The devices were tested in a validated large animal model of hypertrophic scarring. Phase I within-patient controlled clinical trials were conducted to confirm their safety and efficacy in scar reduction in patients undergoing abdominoplasty surgery. Results Among the tested materials and device applicators, a polymer device was developed that effectively off-loaded high tension wounds and blocked pro-fibrotic pathways and excess scar formation in red Duroc swine. In humans, different anatomic sites exhibit unique biomechanical properties that may correlate with the propensity to form scars. In the clinical trial, utilization of this device significantly reduced incisional scar formation and improved scar appearance for up to 12 months compared with control incisions that underwent routine postoperative care. Innovation This is the first device that is able to precisely control the mechanical environment of incisional wounds and has been demonstrated in multiple clinical trials to significantly reduce scar formation after surgery. Conclusion Mechanomodulatory strategies to control the incisional wound environment can significantly reduce pathologic scarring and fibrosis after surgery. PMID:24527342

Development and mechanical properties of construction materials from lunar simulants

NASA Technical Reports Server (NTRS)

Desai, Chandra S.

1990-01-01

The development of construction materials such as concrete from lunar soils without the use of water requires a different methodology than that used for conventional terrestrial concrete. Currently, this research involves two aspects: (1) liquefaction of lunar simulants with various additives in a furnace so as to produce a construction material like an intermediate ceramic; and (2) cyclic loading of simulant with different initial vacuums and densities with respect to the theoretical maximum densities (TMD). In both cases, bending, triaxial compression, extension, and hydrostatic tests will be performed to define the stress-strain strength response of the resulting materials. In the case of the intermediate ceramic, bending and available multiaxial test devices will be used, while for the compacted case, tests will be performed directly in the new device. The tests will be performed by simulating in situ confining conditions. A preliminary review of high-purity metal is also conducted.

Defense Threat Reduction Agency Radiochemical Needs

NASA Astrophysics Data System (ADS)

Walsh, Michael A. R.; Velazquez, Daniel L.

2009-08-01

The United States Government (USG) first developed nuclear forensics-related capabilities to analyze radiological and nuclear materials, including underground nuclear test debris and interdicted materials. Nuclear forensics is not a new mission for Department of Defense (DoD). The department's existing nuclear forensics capability is the result of programs that span six (6) decades and includes activities to assess foreign nuclear weapons testing activities, monitor and verify nuclear arms control treaties, and to support intelligence and law enforcement activities. Today, nuclear forensics must support not only weapons programs and nuclear smuggling incidents, but also the scientific analysis and subsequent attribution of terrorists' use of radiological or nuclear materials/devices. Nuclear forensics can help divulge the source of origin of nuclear materials, the type of design for an interdicted or detonated device, as well as the pathway of the materials or device to the incident. To accomplish this mission, the USG will need trained radiochemists and nuclear scientists to fill new positions and replace the retiring staff.

The high frequency light load fatigue testing machine based on giant magnetostrictive material and stroke multiplier

NASA Astrophysics Data System (ADS)

Wang, M. D.; Li, D. S.; Huang, Y.; Zhang, C.; Zhong, K. M.; Sun, L. N.

2013-08-01

In the notebook and clamshell mobile phone, data communication wire often requires repeated bending. Generally, communication wire with the actual application conditions, the test data cannot assess bending resistance performance of data communication wire is tested conventionally using wires with weights of 90 degree to test bending number, this test method and device is not fully reflect the fatigue performance in high frequency and light load application condition, at the same time it has a large difference between the test data of the long-term reliability of high frequency and low load conditions. In this paper, high frequency light load fatigue testing machine based on the giant magnetostrictive material and stroke multiplier is put forward, in which internal reflux stroke multiplier is driven by giant magnetostrictive material to realize the rapid movement of light load. This fatigue testing device has the following advantages: (1) When the load is far less than the friction, reducing friction is very effective to improve the device performance. Because the body is symmetrical, the friction loss of radial does not exist in theory, so the stress situation of mechanism is good with high transmission efficiency and long service life. (2) The installation position of the output hydraulic cylinder, can be arranged conveniently as ordinary cylinder. (3) Reciprocating frequency, displacement and speed of high frequency movement can be programmed easily to change with higher position precision. (4)Hydraulic oil in this device is closed to transmit, which does not produce any environment pollution. The device has no hydraulic pump and tank, and less energy conversion processes, so it is with the trend of green manufacturing.

Ignitability test method

NASA Technical Reports Server (NTRS)

Bement, Laurence J.; Schimmel, Morry L.

1989-01-01

To overcome serious weaknesses in determining the performance of initiating devices, a novel 'ignitability test method', representing actual design interfaces and ignition materials, has been developed. Ignition device output consists of heat, light, gas an burning particles. Past research methods have evaluated these parameters individually. This paper describes the development and demonstration of an ignitability test method combining all these parameters, and the quantitative assessment of the ignition performance of two widely used percussion primers, the M42C1-PA101 and the M42C2-793. The ignition materials used for this evaluation were several powder, granule and pellet sizes of black powder and boron-potassium nitrate. This test method should be useful for performance evaluation of all initiator types, quality assurance, evaluation of ignition interfaces, and service life studies of initiators and ignition materials.

Universal approach to analysis of cavitation and liquid-impingement erosion data

NASA Technical Reports Server (NTRS)

Rao, P. V.; Young, S. G.

1982-01-01

Cavitation erosion experimental data was analyzed by using normalization and curve-fitting techniques. Data were taken from experiments on several materials tested in both a rotating disk device and a magnetostriction apparatus. Cumulative average volume loss rate and time data were normalized relative to the peak erosion rate and the time to peak erosion rate, respectively. From this process a universal approach was derived that can include data on specific materials from different test devices for liquid impingement and cavitation erosion studies.

Characterizing fretting damage in different test media for cardiovascular device durability testing.

PubMed

Weaver, J D; Ramirez, L; Sivan, S; Di Prima, M

2018-06-01

In vitro durability tests of cardiovascular devices are often used to evaluate the potential for fretting damage during clinical use. Evaluation of fretting damage is important because severe fretting can concentrate stress and lead to the loss of structural integrity. Most international standards call for the use of phosphate buffered saline (PBS) for such tests although there has been little evidence to date that the use of PBS is appropriate in terms of predicting the amount of fretting damage that would occur in vivo. In order to determine an appropriate test media for in vitro durability tests where fretting damage is being evaluated, we utilized an in vitro test that is relevant to cardiovascular devices both in terms of dimensions and materials (nitinol, cobalt-chromium, and stainless steel) to characterize fretting damage in PBS, deionized water (DIW), and heparinized porcine blood. Overall, tests conducted in blood were found to have increased levels of fretting damage over tests in DIW or PBS, although the magnitude of this difference was smaller than the variability for each test media. Tests conducted in DIW and PBS led to mostly similar amounts of fretting damage with the exception of one material combination where DIW had greatly reduced damage compared to PBS and blood. Differences in fretting damage among materials were also observed with nitinol having less fretting damage than stainless steel or cobalt-chromium. In general, evaluating fretting damage in PBS or DIW may be appropriate although caution should be used when selecting test media and interpreting results given some of the differences observed across different materials. Published by Elsevier Ltd.

[Analysis of bactericidal material generated by electrical devices advertising bactericidal ability against bacteria on the agar gel plates].

PubMed

Nishimura, Hidekazu

2012-11-01

Several Japanese companies sell electrical devices advertised as effective in inactivating viruses and killing bacteria by releasing special materials, e.g., Plasmacluster ions, Nanoe particle and minus ions, into the air. These companies claim that their devices killed bacteria on plates in their own experiments. We tested device effectiveness using the same experiments from the Plasmacluster ioniser SHARP Co., Japan, the Nanoe generator Panasonic Co., Japan, and the Vion KING JIM Co., Japan, to test their advertising claims. Bactericidal ability on agar plate was tested, using Staphylococcus aureus, Pseudomonas aeruginosa, Bacillus cereus, and Enterococcus faecalis as follows: the medium containing a certain amount of each bacterium was put onto an agar plate and smeared. Plates were kept in a closed chamber (inner volume 14.4 m3) or a glove box (inner volume 0.2 m), with one of the devices run for 2 hours. Plates not exposed to any device were used as controls. Each plate was retrieved and put in an incubator to count the number of bacterial colonies formed on the plate. There was no significant difference in the number of colonies on plates exposed to devices compared to control, in the number for all devices, or in all bacteria tested in experiments in the 14.4 m3 chamber. These results strongly suggest that these devices have almost no bactericidal effect, at least in space exceeding this volume. Colony formation was suppressed in the glove box in all devices and in all bacteria tested except P. aeruginosa, although the degree of suppression differed among experiments. The colony formation suppression mechanism was analyzed, and indicated that:colony formation did not change even after the removal of Plasmacluster ions, Nanoe particles, or negative ions from the air, while colony formation was decreased drastically by the removal of ozone from space, which was revealed to be generated inevitably during device operation. These results strongly suggest that the bactericidal effect seen only on the agar plate in narrow space was explained by ozone released in space as a by-product, not by special materials as advertising claimed. It is thus important to analyze the effect of special materials such as those done in this study and to suggest the involvement of ozone as the true cause, as have been done in this study, in evaluating bactericidal effect or viral inactivation as advertised by these companies.

TID Effects of High-Z Material Spot Shields on FPGA Using MPTB Data

NASA Technical Reports Server (NTRS)

Hardage, Donna (Technical Monitor); Crain, S. H.; Mazur, J. E.; Looper, M. D.

2003-01-01

An experiment on the Microelectronics and Photonics Test Bed (MPTB) was testing lield programmable gate arrays using spot shields to extend the life of some of the devices being tested. It was expected that the unshielded parts would fail from a total ionizing dose (TID) and yet the opposite occurred. The data show that the devices failing from the TID effects are those with the spot shields attached. This effort is to determine the mechanism by which the environment is interacting with the high-Z material to enhance the TID in these field programmable gate arrays.

Electrode holder useful in a corrosion testing device

DOEpatents

Murphy, R.J. Jr.; Jamison, D.E.

1986-08-19

The present invention is directed to an apparatus and method for holding one or more test electrodes of precisely known exposed surface area. The present invention is particularly useful in a device for determining the corrosion properties of the materials from which the test electrodes have been formed. The present invention relates to a device and method for holding the described electrodes wherein the exposed surface area of the electrodes is only infinitesimally decreased. Further, in the present invention the exposed, electrically conductive surface area of the contact devices is small relative to the test electrode surface area. The holder of the present invention conveniently comprises a device for contacting and engaging each test electrode at two point contacts infinitesimally small in relation to the exposed surface area of the electrodes. 4 figs.

Electrode holder useful in a corrosion testing device

DOEpatents

Murphy, Jr., Robert J.; Jamison, Dale E.

1986-01-01

The present invention is directed to an apparatus and method for holding one or more test electrodes of precisely known exposed surface area. The present invention is particularly useful in a device for determining the corrosion properties of the materials from which the test electrodes have been formed. The present invention relates to a device and method for holding the described electrodes wherein the exposed surface area of the electrodes is only infinitesimally decreased. Further, in the present invention the exposed, electrically conductive surface area of the contact devices is small relative to the test electrode surface area. The holder of the present invention conveniently comprises a device for contacting and engaging each test electrode at two point contacts infinitesimally small in relation to the exposed surface area of the electrodes.

Efficiency of filtering materials used in respiratory protective devices against nanoparticles.

PubMed

Brochocka, Agnieszka; Makowski, Krzysztof; Majchrzycka, Katarzyna; Grzybowski, Piotr

2013-01-01

The basic aim of this research was to establish the efficiency of filtering materials widely used in respiratory protection devices with particular interest in their porosity, degree of electric and changeable process parameters, such as the flow rate of the test nanoaerosol and the size range of nanoparticles. Tests were carried out with an NaCl solid aerosol of 3.2 × 105 particles/cm3 for the range of particle size of 7-270 nm, at aerosol flow rate of 1800, 2700, 3600, 4500 and 5400 L/h. The tests showed that electrospun nonwovens were the most effective filtering materials for nanoparticles over 20 nm. Melt-blown electret nonwovens with lower porosity than electrospun nonwovens had higher values of penetration of 1%-4%. Those materials provided very efficient protection against nanoparticles of certain sizes only.

NASA SBIR product catalog, 1991

NASA Technical Reports Server (NTRS)

1991-01-01

This catalog is a partial list of products of NASA SBIR (Small Business Innovation Research) projects that have advanced to some degree into Phase 3. While most of the products evolved from work conducted during SBIR Phase 1 and 2, a few advanced to commercial status solely from Phase 1 activities. The catalog presents information provided to NASA by SBIR contractors who wished to have their products exhibited at Technology 2001, a NASA-sponsored technology transfer conference held in San Jose, California, on December 4, 5, and 6, 1991. The catalog presents the product information in the following technology areas: computer and communication systems; information processing and AI; robotics and automation; signal and image processing; microelectronics; electronic devices and equipment; microwave electronic devices; optical devices and lasers; advanced materials; materials processing; materials testing and NDE; materials instrumentation; aerodynamics and aircraft; fluid mechanics and measurement; heat transfer devices; refrigeration and cryogenics; energy conversion devices; oceanographic instruments; atmosphere monitoring devices; water management; life science instruments; and spacecraft electromechanical systems.

Preface to the special issue of Solid State Electronics EUROSOI/ULIS 2017

NASA Astrophysics Data System (ADS)

Nassiopoulou, Androula G.

2018-05-01

This special issue is devoted to selected papers presented at the EuroSOI-ULIS2017 international conference, held in Athens on 3-5 April 2017. EuroSOI-ULIS2017 Conference was mainly devoted to Si devices, which constitute the basic building blocks of any microelectronic circuit. It included papers on advanced Si technologies, novel nanoscale devices, advanced electronic materials and device architectures, mechanisms involved, test structures, substrate materials and technologies, modeling/simulation and characterization. Both CMOS and beyond CMOS devices were presented, covering the More Moore domain, as well as new functionalities in silicon-compatible nanostructures and innovative devices, representing the More than Moore domain (on-chip sensors, biosensors, energy harvesting devices, RF passives, etc.).

Nonlinear optical thin films

NASA Technical Reports Server (NTRS)

Leslie, Thomas M.

1993-01-01

A focused approach to development and evaluation of organic polymer films for use in optoelectronics is presented. The issues and challenges that are addressed include: (1) material synthesis, purification, and the tailoring of the material properties; (2) deposition of uniform thin films by a variety of methods; (3) characterization of material physical properties (thermal, electrical, optical, and electro-optical); and (4) device fabrication and testing. Photonic materials, devices, and systems were identified as critical technology areas by the Department of Commerce and the Department of Defense. This approach offers strong integration of basic material issues through engineering applications by the development of materials that can be exploited as the active unit in a variety of polymeric thin film devices. Improved materials were developed with unprecedented purity and stability. The absorptive properties can be tailored and controlled to provide significant improvement in propagation losses and nonlinear performance. Furthermore, the materials were incorporated into polymers that are highly compatible with fabrication and patterning processes for integrated optical devices and circuits. By simultaneously addressing the issues of materials development and characterization, keeping device design and fabrication in mind, many obstacles were overcome for implementation of these polymeric materials and devices into systems. We intend to considerably improve the upper use temperature, poling stability, and compatibility with silicon based devices. The principal device application that was targeted is a linear electro-optic modulation etalon. Organic polymers need to be properly designed and coupled with existing integrated circuit technology to create new photonic devices for optical communication, image processing, other laser applications such as harmonic generation, and eventually optical computing. The progression from microscopic sample to a suitable film-forming material in a working device is a complex, multifaceted endeavor. It requires close attention to maintaining the optical properties of the electro-optic active portion of the polymer while manipulating the polymer structure to obtain the desired secondary polymer properties.

Devices for SRF material characterization

DOE PAGES

Goudket, Philippe; Xiao, B.; Junginger, T.

2016-10-07

The surface resistance Rs of superconducting materials can be obtained by measuring the quality factor of an elliptical cavity excited in a transverse magnetic mode (TM010). The value obtained has however to be taken as averaged over the whole surface. A more convenient way to obtain Rs, especially of materials which are not yet technologically ready for cavity production, is to measure small samples instead. These can be easily man ufactured at low cost, duplicated and placed in film deposition and surface analytical tools. A commonly used design for a device to measure Rs consists of a cylindrical cavity excitedmore » in a transverse electric (TE110) mode with the sample under test serving as one replaceable endplate. Such a cavity has two drawbacks. For reasonably small samples the resonant frequency will be larger than frequencies of interest concerning SRF application and it requires a reference sample of known Rs. In this article we review several devices which have been designed to overcome these limitations, reaching sub - nΩ resolution in some cases. Some of these devices also comprise a parameter space in frequency and temperature which is inaccessible to standard cavity tests, making them ideal tools to test theoretical surface resistance models.« less

Devices for SRF material characterization

DOE Office of Scientific and Technical Information (OSTI.GOV)

Goudket, Philippe; Xiao, B.; Junginger, T.

The surface resistance Rs of superconducting materials can be obtained by measuring the quality factor of an elliptical cavity excited in a transverse magnetic mode (TM010). The value obtained has however to be taken as averaged over the whole surface. A more convenient way to obtain Rs, especially of materials which are not yet technologically ready for cavity production, is to measure small samples instead. These can be easily man ufactured at low cost, duplicated and placed in film deposition and surface analytical tools. A commonly used design for a device to measure Rs consists of a cylindrical cavity excitedmore » in a transverse electric (TE110) mode with the sample under test serving as one replaceable endplate. Such a cavity has two drawbacks. For reasonably small samples the resonant frequency will be larger than frequencies of interest concerning SRF application and it requires a reference sample of known Rs. In this article we review several devices which have been designed to overcome these limitations, reaching sub - nΩ resolution in some cases. Some of these devices also comprise a parameter space in frequency and temperature which is inaccessible to standard cavity tests, making them ideal tools to test theoretical surface resistance models.« less

Addressing Research and Development Gaps for Plasma-Material Interactions with Linear Plasma Devices

DOE Office of Scientific and Technical Information (OSTI.GOV)

Rapp, Juergen

Plasma-material interactions in future fusion reactors have been identified as a knowledge gap to be dealt with before any next step device past ITER can be built. The challenges are manifold. They are related to power dissipation so that the heat fluxes to the plasma-facing components can be kept at technologically feasible levels; maximization of the lifetime of divertor plasma-facing components that allow for steadystate operation in a reactor to reach the neutron fluence required; the tritium inventory (storage) in the plasma-facing components, which can lead to potential safety concerns and reduction in the fuel efficiency; and it is relatedmore » to the technology of the plasma-facing components itself, which should demonstrate structural integrity under the high temperatures and high neutron fluence. While the dissipation of power exhaust can and should be addressed in high power toroidal devices, the interaction of the plasma with the materials can be best addressed in dedicated linear devices due to their cost effectiveness and ability to address urgent research and development gaps more timely. However, new linear plasma devices are needed to investigate the PMI under fusion reactor conditions and test novel plasma-facing components. Existing linear devices are limited either in their flux, their reactor-relevant plasma transport regimes in front of the target, their fluence, or their ability to test material samples a priori exposed to high neutron fluence. The proposed Material Plasma Exposure eXperiment (MPEX) is meant to address those deficiencies and will be designed to fulfill the fusion reactor-relevant plasma parameters as well as the ability to expose a priori neutron activated materials to plasmas.« less

New Technology for Microfabrication and Testing of a Thermoelectric Device for Generating Mobile Electrical Power

NASA Technical Reports Server (NTRS)

Prasad, Narashimha S.; Taylor, Patrick J.; Trivedi, Sudhir B.; Kutcher, Susan

2010-01-01

We report the results of fabrication and testing of a thermoelectric power generation module. The module was fabricated using a new "flip-chip" module assembly technique that is scalable and modular. This technique results in a low value of contact resistivity ( < or = 10(exp 5) Ohms-sq cm). It can be used to leverage new advances in thin-film and nanostructured materials for the fabrication of new miniature thermoelectric devices. It may also enable monolithic integration of large devices or tandem arrays of devices on flexible or curved surfaces. Under mild testing, a power of 22 mW/sq cm was obtained from small (<100 K) temperature differences. At higher, more realistic temperature differences, approx.500 K, where the efficiency of these materials greatly improves, this power density would scale to between 0.5 and 1 Watt/cm2. These results highlight the excellent potential for the generation and scavenging of electrical power of practical and usable magnitude for remote applications using thermoelectric power generation technologies.

Testing methods and techniques: Strength of materials and components. A compilation

NASA Technical Reports Server (NTRS)

1971-01-01

The methods, techniques, and devices used in testing the mechanical properties of various materials are presented. Although metals and metal alloys are featured prominently, some of the items describe tests on a variety of other materials, from concrete to plastics. Many of the tests described are modifications of standard testing procedures, intended either to adapt them to different materials and conditions, or to make them more rapid and accurate. In either case, the approaches presented can result in considerable cost savings and improved quality control. The compilation is presented in two sections. The first deals specifically with material strength testing; the second treats the special category of fracture and fatigue testing.

Smart Materials for Electromagnetic and Optical Applications

NASA Astrophysics Data System (ADS)

Ramesh, Prashanth

The research presented in this dissertation focuses on the development of solid-state materials that have the ability to sense, act, think and communicate. Two broad classes of materials, namely ferroelectrics and wideband gap semiconductors were investigated for this purpose. Ferroelectrics possess coupled electromechanical behavior which makes them sensitive to mechanical strains and fluctuations in ambient temperature. Use of ferroelectrics in antenna structures, especially those subject to mechanical and thermal loads, requires knowledge of the phenomenological relationship between the ferroelectric properties of interest (especially dielectric permittivity) and the external physical variables, viz. electric field(s), mechanical strains and temperature. To this end, a phenomenological model of ferroelectric materials based on the Devonshire thermodynamic theory was developed. This model was then used to obtain a relationship expressing the dependence of the dielectric permittivity on the mechanical strain, applied electric field and ambient temperature. The relationship is shown to compare well with published experimental data and other related models in literature. A model relating ferroelectric loss tangent to the applied electric field and temperature is also discussed. Subsequently, relationships expressing the dependence of antenna operating frequency and radiation efficiency on those external physical quantities are described. These relationships demonstrate the tunability of load-bearing antenna structures that integrate ferroelectrics when they are subjected to mechanical and thermal loads. In order to address the inability of ferroelectrics to integrate microelectronic devices, a feature needed in a material capable of sensing, acting, thinking and communicating, the material Gallium Nitride (GaN) is pursued next. There is an increasing utilization of GaN in the area of microelectronics due to the advantages it offers over other semiconductors. This dissertation demonstrates GaN as a candidate material well suited for novel microelectromechanical systems. The potential of GaN for MEMS is demonstrated via the design, analysis, fabrication, testing and characterization of an optical microswitch device actuated by piezoelectric and electrostrictive means. The piezoelectric and electrostrictive properties of GaN and its differences from common piezoelectrics are discussed before elaborating on the device configuration used to implement the microswitch device. Next, the development of two recent fabrication technologies, Photoelectrochemical etch and Bias-enabled Dark Electrochemical etch, used to realize the 3-dimensional device structure in GaN are described in detail. Finally, an ultra-low-cost, laser-based, non-contact approach to test and characterize the microswitch device is described, followed by the device testing results.

49 CFR 572.180 - Incorporated materials.

Code of Federal Regulations, 2012 CFR

2012-10-01

... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST DEVICES 2re Side Impact Crash Test... 50th Percentile Adult Male Side Impact Crash Test Dummy, February 2008,” incorporated by reference in...

Exploring the Electronic Landscape at Interfaces and Junctions in Semiconductor Nanowire Devices with Subsurface Local Probing of Carrier Dynamics

NASA Astrophysics Data System (ADS)

McGuckin, Terrence

The solid state devices that are pervasive in our society, are based on building blocks composed of interfaces between materials and junctions that manipulate how charge carriers behave in a device. As the dimensions of these devices are reduced to the nanoscale, surfaces and interfaces play a larger role in the behavior of carriers in devices and must be thoroughly investigated to understand not only the material properties but how these materials interact. Separating the effects of these different building blocks is a challenge, as most testing methods measure the performance of the whole device. Semiconductor nanowires represent an excellent test system to explore the limits of size and novel device structures. The behavior of charge carriers in semiconductor nanowire devices under operational conditions is investigated using local probing technique electron beam induced current (EBIC). The behavior of locally excited carriers are driven by the forces of drift, from electric fields within a device at junctions, surfaces, contacts and, applied voltage bias, and diffusion. This thesis presents the results of directly measuring these effects spatially with nanometer resolution, using EBIC in Ge, Si, and complex heterostructure GaAs/AlGaAs nanowire devices. Advancements to the EBIC technique, have pushed the resolution from tens of nanometers down to 1 to 2 nanometers. Depth profiling and tuning of the interaction volume allows for the separating the signal originating from the surface and the interior of the nanowire. Radial junctions and variations in bands can now be analyzed including core/shell hetero-structures. This local carrier probing reveals a number of surprising behaviors; Most notably, directly imaging the evolution of surface traps filling with electrons causing bandbending at the surface of Ge nanowires that leads to an enhancement in the charge separation of electrons and holes, and extracting different characteristic lengths from GaAs and AlGaAs in core/shell nanowires. For new and emerging solid state materials, understanding charge carrier dynamics is crucial to designing functional devices. Presented here are examples of the wide application of EBIC, and its variants, through imaging domains in ferroelectric materials, local electric fields and defects in 2D semiconductor material MoS2, and gradients in doping profiles of solar cells. Measuring the local behavior of carrier dynamics, EBIC has the potential to be a key metrology technique in correlative microscopy, enabling a deeper understanding of materials and how they interact within devices.

Advanced development of double-injection, deep-impurity semiconductor switches

NASA Technical Reports Server (NTRS)

Hanes, M. H.

1987-01-01

Deep-impurity, double-injection devices, commonly refered to as (DI) squared devices, represent a class of semiconductor switches possessing a very high degree of tolerance to electron and neutron irradiation and to elevated temperature operation. These properties have caused them to be considered as attractive candidates for space power applications. The design, fabrication, and testing of several varieties of (DI) squared devices intended for power switching are described. All of these designs were based upon gold-doped silicon material. Test results, along with results of computer simulations of device operation, other calculations based upon the assumed mode of operation of (DI) squared devices, and empirical information regarding power semiconductor device operation and limitations, have led to the conculsion that these devices are not well suited to high-power applications. When operated in power circuitry configurations, they exhibit high-power losses in both the off-state and on-state modes. These losses are caused by phenomena inherent to the physics and material of the devices and cannot be much reduced by device design optimizations. The (DI) squared technology may, however, find application in low-power functions such as sensing, logic, and memory, when tolerance to radiation and temperature are desirable (especially is device performance is improved by incorporation of deep-level impurities other than gold.

21 CFR 866.6050 - Ovarian adnexal mass assessment score test system.

Code of Federal Regulations, 2012 CFR

2012-04-01

... ovarian/adnexal mass assessment test system is a device that measures one or more proteins in serum or... § 866.1(e). (c) Black box warning. Under section 520(e) of the Federal Food, Drug, and Cosmetic Act... box and must appear in all advertising, labeling, and promotional material for these devices. That...

21 CFR 866.6050 - Ovarian adnexal mass assessment score test system.

Code of Federal Regulations, 2014 CFR

2014-04-01

... ovarian/adnexal mass assessment test system is a device that measures one or more proteins in serum or... § 866.1(e). (c) Black box warning. Under section 520(e) of the Federal Food, Drug, and Cosmetic Act... box and must appear in all advertising, labeling, and promotional material for these devices. That...

In vitro wear of various orthotic device materials.

PubMed

Casey, Jeffery; Dunn, William J; Wright, Edward

2003-11-01

Orthotic devices are advocated to decrease occlusal attrition caused by bruxism but tend to wear with time. This study investigated the wear rate of various materials used to fabricate orthotic devices. Five experimental groups (n=8) were studied: Splint Biocryl autopolymerized (SBA), Splint Biocryl autopolymerized plus additional heat and pressure (SBHP), Forestacryl autopolymerized (FA), Forestacryl autopolymerized plus additional heat and pressure (FHP), and Quick Splint 15-minute (QS), light-polymerized composite. Specimens were mounted to the base of a universal testing machine. A wear device using steatite balls and a load of 9.1 kg was positioned against the specimens, submerged in a 37 degrees C water bath and subjected to 2500 reciprocal cycles. Wear, in micrometers, was calculated as the maximum peak to valley measurement (Ry) using profilometry. Data were subjected to analysis of variance (ANOVA) and Tukey's HSD (alpha=.05). Mean acrylic wear in micrometers was as follows: FA 6.8 +/-3.0; FHP 7.1 +/- 1.8; SBA 20.4 +/- 5.6; SBHP 23.7 +/- 7.8; and QS 23.8 +/- 6.9. One-way ANOVA detected significant differences between groups (P<.001); the Tukey honestly significant difference test determined that FA and FHP specimens were significantly more resistant to wear than all other specimens (P=.007). Differences in in vitro wear resistance among various orthotic device materials exist. The in vitro wear resistance among other autopolymerizing materials appears to be related to proprietary differences.

Semiconductor Materials for High Frequency Solid State Sources.

DTIC Science & Technology

1985-01-18

saturation on near and submicron-scale device performance. The motivation for this is as follows: Presently, individual semiconductors are accepted or...basis of all FET scaling procedures; and is a major motivating factor for going to submicron structures. This scaling was tested with the 4 following...performance. The motivation for this is as follows: Presently, individual semiconductors are accepted or rejected as candidate device materials based, in

Design principles of descent vehicles with an inflatable braking device

NASA Astrophysics Data System (ADS)

Alexashkin, S. N.; Pichkhadze, K. M.; Finchenko, V. S.

2013-12-01

A new type of descent vehicle (DVs) is described: a descent vehicle with an inflatable braking device (IBD DV). IBD development issues, as well as materials needed for the design, manufacturing, and testing of an IBD and its thermal protection, are discussed. A list is given of Russian integrated test facilities intended for testing IBD DVs. Progress is described in the development of IBD DVs in Russia and abroad.

Smart Materials Meet Multifunctional Biomedical Devices: Current and Prospective Implications for Nanomedicine.

PubMed

Genchi, Giada Graziana; Marino, Attilio; Tapeinos, Christos; Ciofani, Gianni

2017-01-01

With the increasing advances in the fabrication and in monitoring approaches of nanotechnology devices, novel materials are being synthesized and tested for the interaction with biological environments. Among them, smart materials in particular provide versatile and dynamically tunable platforms for the investigation and manipulation of several biological activities with very low invasiveness in hardly accessible anatomical districts. In the following, we will briefly recall recent examples of nanotechnology-based materials that can be remotely activated and controlled through different sources of energy, such as electromagnetic fields or ultrasounds, for their relevance to both basic science investigations and translational nanomedicine. Moreover, we will introduce some examples of hybrid materials showing mutually beneficial components for the development of multifunctional devices, able to simultaneously perform duties like imaging, tissue targeting, drug delivery, and redox state control. Finally, we will highlight challenging perspectives for the development of theranostic agents (merging diagnostic and therapeutic functionalities), underlining open questions for these smart nanotechnology-based devices to be made readily available to the patients in need.

Use of patient specific 3D printed (3DP) neurovascular phantoms for mechanical assessment of devices used in image guided minimally invasive procedures

NASA Astrophysics Data System (ADS)

Tabaczynski, Janelle R.; Stoll, Thomas; Shepard, Lauren; Siddiqui, Mohamed I. G.; Karkhanis, Nitant V.; Sommer, Kelsey; Siddiqui, Adnan H.; Ionita, Ciprian N.

2018-03-01

Patient-specific 3D printed phantoms (3DP) can reproduce accurate patient geometry and provide precise tools for Endovascular Image Guided Interventions (EIGI) simulations. We propose to build and test 3DP phantoms which mimic the arterial wall elasticity and surface properties and demonstrate their utility in comprehensive EIGI simulations. 3DP idealized and patient specific vascular phantoms were manufactured using Stratasys Objet 500 Connex 3. The idealized phantoms were created using a sine wave shape, patient specific phantoms were based on CT- angiography volumes. The phantoms were coated with a hydrophilic material to mimic vascular surface properties. We tested various endovascular procedures using an Interventional Device Testing Equipment (IDTE) 2000 and measured push/pull force used to actuate endovascular devices during EIGIs. The force needed to advance devices in neurovascular phantoms varied based on tortuosity, material and coating, ranging from -3 to 21 grams-force. Hydrophilic coating reduced maximum force from 21 to 4.8 grams-force in the same model. IDTE 2000 results of neurovascular models were compared to hand manipulation of guidewire access using a six-axis force sensor with forces ranging from -50 to 440 grams. The clot retriever tested in carotid models experienced most friction around tortuous bends ranging from -65 to -90 grams-force, with increasing rigidity of materials creating increased friction. Sine wave model forces varied from -2 to 105 grams. 3DP allows manufacturing of vascular phantoms with precise mechanical and surface properties which can be used for EIGI simulations for imaging protocol optimization and device behavior assessment.

US Navy superconductivity program

NASA Technical Reports Server (NTRS)

Gubser, Donald U.

1991-01-01

Both the new high temperature superconductors (HTS) and the low temperature superconductors (LTS) are important components of the Navy's total plan to integrate superconductivity into field operational systems. Fundamental research is an important component of the total Navy program and focuses on the HTS materials. Power applications (ship propulsion) use LTS materials while space applications (millimeter wave electronics) use HTS materials. The Space Experiment to be conducted at NRL will involve space flight testing of HTS devices built by industry and will demonstrate the ability to engineer and space qualify these devices for systems use. Another important component of the Navy's effort is the development of Superconducting Quantum Interference Device (SQUID) magnetometers. This program will use LTS materials initially, but plans to implement HTS materials as soon as possible. Hybrid HTS/LTS systems are probable in many applications. A review of the status of the Navy's HTS materials research is given as well as an update on the Navy's development efforts in superconductivity.

Two-year performance study of porous, thermoset, shape memory polyurethanes intended for vascular medical devices

NASA Astrophysics Data System (ADS)

Weems, Andrew C.; Boyle, Anthony J.; Maitland, Duncan J.

2017-03-01

The long-term shape-recovery behavior of shape memory polymers has often been shown to be dependent on the length of time the material has been stored in the secondary shape. Typically, recovery performance and shape fixity will decrease with increased time in the secondary shape. In medical materials, a shelf-life is crucial to establish as it sets the upper threshold for device performance in a clinical setting, and a reduction in shape recovery would limit the development of SMP medical devices. Here, we present a two-year study of strain recovery, strain fixity, and shape recovery kinetics for passively and actively actuated SMPs intended for vascular devices. While kinetic experiments using immersion DMA indicate slight material relaxation and a decrease in the time to recovery, these changes are not found for bulk recovery experiments. The results indicate that a two-year shelf-life for these SMPs is very reasonable, as there is no change in the recovery kinetics, strain recovery, or strain fixity associated with this aging time. Further, a thermal accelerated aging test is presented for more rapid testing of the shape memory behavior of these SMPs and is compared with the real time aging results, indicating that this test is a reasonable indicator of the two-year behavior.

Design of a Helmet Liner for Improved Low Velocity Impact Protection

DTIC Science & Technology

2013-05-01

FIGURE 14. MONORAIL DROP TEST WITH DOT-SIZE C HEADFORM AND HEMISPHERICAL ANVIL ........................... 14  FIGURE 15. ACH PAD CONFIGURATION. LEFT...materials. In this project, the monorail drop test device, used for the helmeted headform drop test, was modified for material testing as shown in Figure...a guided free fall drop test using a monorail drop test apparatus as shown in Figure 14. All helmets tested in this study were ACH-Size Large and

Design, Fabrication, and In Vitro Testing of an Anti-biofouling Glaucoma Micro-shunt.

PubMed

Harake, Ryan S; Ding, Yuzhe; Brown, J David; Pan, Tingrui

2015-10-01

Glaucoma, one of the leading causes of irreversible blindness, is a progressive neurodegenerative disease. Chronic elevated intraocular pressure (IOP), a prime risk factor for glaucoma, can be treated by aqueous shunts, implantable devices, which reduce IOP in glaucoma patients by providing alternative aqueous outflow pathways. Although initially effective at delaying glaucoma progression, contemporary aqueous shunts often lead to numerous complications and only 50% of implanted devices remain functional after 5 years. In this work, we introduce a novel micro-device which provides an innovative platform for IOP reduction in glaucoma patients. The device design features an array of parallel micro-channels to provide precision aqueous outflow resistance control. Additionally, the device's microfluidic channels are composed of a unique combination of polyethylene glycol materials in order to provide enhanced biocompatibility and resistance to problematic channel clogging from biofouling of aqueous proteins. The microfabrication process employed to produce the devices results in additional advantages such as enhanced device uniformity and increased manufacturing throughput. Surface characterization experimental results show the device's surfaces exhibit significantly less non-specific protein adsorption compared to traditional implant materials. Results of in vitro flow experiments verify the device's ability to provide aqueous resistance control, continuous long-term stability through 10-day protein flow testing, and safety from risk of infection due to bacterial ingression.

29 CFR 1919.90 - Documentation.

Code of Federal Regulations, 2011 CFR

2011-07-01

...(f) Test Supervision .10(b) Annual Examinations: (see Examinations). Assistant Secretary .2(d) Blocks...). Cargo Gear: Braking Devices .22 Chains .25 Damaged Components .20 Definition .2(b) Derrick Attachment...: (see Gear Certification). Shore-Based Materials Handling Devices .70(a) Chains, Limitations .25...

29 CFR 1919.90 - Documentation.

Code of Federal Regulations, 2012 CFR

2012-07-01

...(f) Test Supervision .10(b) Annual Examinations: (see Examinations). Assistant Secretary .2(d) Blocks...). Cargo Gear: Braking Devices .22 Chains .25 Damaged Components .20 Definition .2(b) Derrick Attachment...: (see Gear Certification). Shore-Based Materials Handling Devices .70(a) Chains, Limitations .25...

Cytocompatibility testing of cell culture modules fabricated from specific candidate biomaterials using injection molding.

PubMed

Hiebl, Bernhard; Lützow, Karola; Lange, Maik; Jung, Friedrich; Seifert, Barbara; Klein, Frank; Weigel, Thomas; Kratz, Karl; Lendlein, Andreas

2010-07-01

Most polymers used in clinical applications today are materials that have been developed originally for application areas other than biomedicine. Testing the cell- and tissue-compatibility of novel materials in vitro and in vivo is of key importance for the approval of medical devices and is regulated according to the Council Directive 93/42/EEC of the European communities concerning medical devices. In the standardized testing methods the testing sample is placed in commercially available cell culture plates, which are often made from polystyrene. Thus not only the testing sample itself influences cell behavior but also the culture vessel material. In order to exclude this influence, a new system for cell testing will be presented allowing a more precise and systematic investigation by preparing tailored inserts which are made of the testing material. Inserts prepared from polystyrene, polycarbonate and poly(ether imide) were tested for their cytotoxity and cell adherence. Furthermore a proof of principle concerning the preparation of inserts with a membrane-like surface structure and its surface modification was established. Physicochemical investigations revealed a similar morphology and showed to be very similar to the findings to analogous preparations and modifications of flat-sheet membranes. Copyright (c) 2010 Elsevier B.V. All rights reserved.

Determination of elastomeric foam parameters for simulations of complex loading.

PubMed

Petre, M T; Erdemir, A; Cavanagh, P R

2006-08-01

Finite element (FE) analysis has shown promise for the evaluation of elastomeric foam personal protection devices. Although appropriate representation of foam materials is necessary in order to obtain realistic simulation results, material definitions used in the literature vary widely and often fail to account for the multi-mode loading experienced by these devices. This study aims to provide a library of elastomeric foam material parameters that can be used in FE simulations of complex loading scenarios. Twelve foam materials used in footwear were tested in uni-axial compression, simple shear and volumetric compression. For each material, parameters for a common compressible hyperelastic material model used in FE analysis were determined using: (a) compression; (b) compression and shear data; and (c) data from all three tests. Material parameters and Drucker stability limits for the best fits are provided with their associated errors. The material model was able to reproduce deformation modes for which data was provided during parameter determination but was unable to predict behavior in other deformation modes. Simulation results were found to be highly dependent on the extent of the test data used to determine the parameters in the material definition. This finding calls into question the many published results of simulations of complex loading that use foam material parameters obtained from a single mode of testing. The library of foam parameters developed here presents associated errors in three deformation modes that should provide for a more informed selection of material parameters.

49 CFR 572.80 - Incorporated materials.

Code of Federal Regulations, 2010 CFR

2010-10-01

... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST DEVICES 9-Month Old Child § 572.80 Incorporated materials. The drawings and specifications referred to in § 572.81(a) that are not set forth in...

Development of a device to simulate tooth mobility.

PubMed

Erdelt, Kurt-Jürgen; Lamper, Timea

2010-10-01

The testing of new materials under simulation of oral conditions is essential in medicine. For simulation of fracture strength different simulation devices are used for test set-up. The results of these in vitro tests differ because there is no standardization of tooth mobility in simulation devices. The aim of this study is to develop a simulation device that depicts the tooth mobility curve as accurately as possible and creates reproducible and scalable mobility curves. With the aid of published literature and with the help of dentists, average forms of tooth classes were generated. Based on these tooth data, different abutment tooth shapes and different simulation devices were designed with a CAD system and were generated with a Rapid Prototyping system. Then, for all simulation devices the displacement curves were created with a universal testing machine and compared with the tooth mobility curve. With this new information, an improved adapted simulation device was constructed. A simulations device that is able to simulate the mobility curve of natural teeth with high accuracy and where mobility is reproducible and scalable was developed.

Microassembly of Heterogeneous Materials using Transfer Printing and Thermal Processing

PubMed Central

Keum, Hohyun; Yang, Zining; Han, Kewen; Handler, Drew E.; Nguyen, Thong Nhu; Schutt-Aine, Jose; Bahl, Gaurav; Kim, Seok

2016-01-01

Enabling unique architectures and functionalities of microsystems for numerous applications in electronics, photonics and other areas often requires microassembly of separately prepared heterogeneous materials instead of monolithic microfabrication. However, microassembly of dissimilar materials while ensuring high structural integrity has been challenging in the context of deterministic transferring and joining of materials at the microscale where surface adhesion is far more dominant than body weight. Here we present an approach to assembling microsystems with microscale building blocks of four disparate classes of device-grade materials including semiconductors, metals, dielectrics, and polymers. This approach uniquely utilizes reversible adhesion-based transfer printing for material transferring and thermal processing for material joining at the microscale. The interfacial joining characteristics between materials assembled by this approach are systematically investigated upon different joining mechanisms using blister tests. The device level capabilities of this approach are further demonstrated through assembling and testing of a microtoroid resonator and a radio frequency (RF) microelectromechanical systems (MEMS) switch that involve optical and electrical functionalities with mechanical motion. This work opens up a unique route towards 3D heterogeneous material integration to fabricate microsystems. PMID:27427243

A Two-Step Absorber Deposition Approach To Overcome Shunt Losses in Thin-Film Solar Cells: Using Tin Sulfide as a Proof-of-Concept Material System

DOE Office of Scientific and Technical Information (OSTI.GOV)

Steinmann, Vera; Chakraborty, Rupak; Rekemeyer, Paul H.

2016-08-31

As novel absorber materials are developed and screened for their photovoltaic (PV) properties, the challenge remains to reproducibly test promising candidates for high-performing PV devices. Many early-stage devices are prone to device shunting due to pinholes in the absorber layer, producing 'false-negative' results. Here, we demonstrate a device engineering solution toward a robust device architecture, using a two-step absorber deposition approach. We use tin sulfide (SnS) as a test absorber material. The SnS bulk is processed at high temperature (400 degrees C) to stimulate grain growth, followed by a much thinner, low-temperature (200 degrees C) absorber deposition. At a lowermore » process temperature, the thin absorber overlayer contains significantly smaller, densely packed grains, which are likely to provide a continuous coating and fill pinholes in the underlying absorber bulk. We compare this two-step approach to the more standard approach of using a semi-insulating buffer layer directly on top of the annealed absorber bulk, and we demonstrate a more than 3.5x superior shunt resistance Rsh with smaller standard error ..sigma..Rsh. Electron-beam-induced current (EBIC) measurements indicate a lower density of pinholes in the SnS absorber bulk when using the two-step absorber deposition approach. We correlate those findings to improvements in the device performance and device performance reproducibility.« less

DEVELOPMENT OF EXPERIMENTAL AUDIOVISUAL DEVICES AND MATERIALS FOR BEGINNING READERS.

ERIC Educational Resources Information Center

GIBSON, CHRISTINE M.; RICHARDS, I.A.

THIS STUDY TESTED THE ARRANGEMENT OF AN INTERRELATED PROGRAM OF PROCEDURES THAT CAN MUTUALLY GENERATE AND NURTURE THE LEARNING PROCESS FOR BEGINNING READING. CLOSE, SYSTEMATIC OBSERVATIONS OF PEOPLE OF VARYING AGES WERE MADE. THE MATERIALS HAD BEEN DESIGNED, FIELD TESTED, AND REFINED BY A LANGUAGE RESEARCH GROUP AT THE HARVARD GRADUATE SCHOOL OF…

Detail design of the surface tension propellant management device for the Intelsat VII communication satellite

NASA Astrophysics Data System (ADS)

Giacalone, Philip L.

1993-06-01

The design of the Intelsat VII surface tension propellant management device (PMD) (an all-welded assembly consisting of about 100 individual components) was developed using a modular design approach that allowed the complex PMD assembly to be divided into smaller modules. The modular approach reduces manufacturing-related technical and schedule risks and allows many components and assemblies to be processed in parallel, while also facilitating the incorporation of quality assurance tests at all critical PMD subassembly levels. The baseline PMD assembly is made from titanium and stainless steel materials. In order to obtain a 100 percent titanium PMD, a new, state-of-the-art fine mesh titanium screen material was developed, tested, and qualified for use as an alternaltive to the stainless steel screen material. The Ti based screen material demonstrated a high level of bubble point performance. It was integrated into a PMD assembly and was successfully qualification tested at the tank assembly level.

Post-Flight Test Results of Acousto-Optic Modulator Devices Subjected to Space Exposure

NASA Technical Reports Server (NTRS)

Prasad, Narasimha S.; Trivedi, Sudhir; Rosemeier, Jolanta; Diestler, Mark

2014-01-01

The objective of the Materials International Space Station Experiment (MISSE) is to study the performance of novel materials when subjected to the synergistic effects of the harsh space environment for several months. MISSE missions provide an opportunity for developing space qualifiable materials. Several laser and lidar components were sent by NASA Langley Research Center (LaRC) as a part of the MISSE 7 mission. The MISSE 7 module was transported to the international space station (ISS) via STS 129 mission that was launched on Nov 16, 2009. Later, the MISSE 7 module was brought back to the earth via the STS 134 that landed on June 1, 2011. The MISSE 7 module that was subjected to exposure in a space environment for more than one and a half years included fiber laser, solid-state laser gain materials, detectors, and semiconductor laser diode. Performance testing of these components is now progressing. In this paper, the results of performance testing of a laser diode module sent by NASA Langley Research Center on MISSE 7 mission will be discussed. This paper will present the comparison of pre-flight and post-flight performance of two different COTS acousto-optic modulator (AOM) devices. Post-flight measurements indicate that these two devices did not undergo any significant performance degradation.

Post-flight test results of acousto-optic modulator devices subjected to space exposure

NASA Astrophysics Data System (ADS)

Prasad, Narasimha S.; Trivedi, Sudhir; Rosemeier, Jolanta; Diestler, Mark

2014-09-01

The objective of the Materials International Space Station Experiment (MISSE) is to study the performance of novel materials when subjected to the synergistic effects of the harsh space environment for several months. MISSE missions provide an opportunity for developing space qualifiable materials. Several laser and lidar components were sent by NASA Langley Research Center (LaRC) as a part of the MISSE 7 mission. The MISSE 7 module was transported to the international space station (ISS) via STS 129 mission that was launched on Nov 16, 2009. Later, the MISSE 7 modulewas brought back to the earth via the STS 134 that landed on June 1, 2011. The MISSE 7 module that was subjected to exposure in space environment for more than one and a half year included fiber laser, solid-state laser gain materials, detectors, and semiconductor laser diode. Performance testing of these components is now progressing. In this paper, the results of performance testing of a laser diode module sent by NASA Langley Research Center on MISSE 7 mission will be discussed. This paper will present the comparison of pre-flight and post-flight performance of two different COTS acousto-optic modulator devices. Post-flight measurements indicate that these two devices did not undergo any significant performance degradation.

Nondestructive evaluation of warm mix asphalt through resonant column testing.

DOT National Transportation Integrated Search

2014-02-01

Non-destructive testing has been used for decades to characterize engineering properties of hot-mix asphalt. Among such tests is the resonant column (RC) test, which is commonly used to characterize soil materials. The resonant column device at Penn ...

Testing Composites

NASA Technical Reports Server (NTRS)

1981-01-01

A device for testing composites for strength characteristics has been developed by Acoustic Emission Technology Corporation. Called the Model 206AU, the system is lightweight and portable. It is comprised of three sections. The "pulser" section injects ultrasonic waves into the material under test. A receiver picks up the simulated stress waves as they pass through the material and relays the signals to the acoustic emission section, where they are electronically analyzed.

Ballast degradation characterized through triaxial test : research results.

DOT National Transportation Integrated Search

2016-06-01

Transportation Technology Center, Inc. (TTCI) : has supported the development of a large-scale : triaxial test device (Figure 1) for testing ballast : size aggregate materials at the University of : Illinois at Urbana-Champaign (UIUC). This new : tes...

Space Qualification Issues in Acousto-optic and Electro-optic Devices

NASA Technical Reports Server (NTRS)

Prasad, Narasimha S.; Taylor, Edward W.; Trivedi, Sudhir; Kutcher, Sue; Soos, Jolanta

2007-01-01

Satellite and space-based applications of photonic devices and systems require operational reliability in the harsh environment of space for extended periods of time. This in turn requires every component of the systems and their packaging to meet space qualifications. Acousto- and electro-optical devices form the major components of many current space based optical systems, which is the focus of this paper. The major space qualification issues are related to: mechanical stability, thermal effects and operation of the devices in the naturally occurring space radiation environment. This paper will discuss acousto- and electro-optic materials and devices with respect to their stability against mechanical vibrations, thermal cycling in operating and non-operating conditions and device responses to space ionizing and displacement radiation effects. Selection of suitable materials and packaging to meet space qualification criteria will also be discussed. Finally, a general roadmap for production and testing of acousto- and electro-optic devices will be discussed.

In-situ photopolymerization and monitoring device for controlled shaping of tissue fillers, replacements, or implants

NASA Astrophysics Data System (ADS)

Schmocker, Andreas M.; Khoushabi, Azadeh; Bourban, Pierre-Etienne; Schizas, Constantin; Pioletti, Dominique; Moser, Christophe

2015-03-01

Photopolymerization is a common tool to harden materials initially in a liquid state. A surgeon can directly trigger the solidification of a dental implant or a bone or tissue filler simply by illumination. Traditionally, photopolymerization has been used mainly in dentistry. Over the last decade advances in material development including a wide range of biocompatible gel- and cement-systems open up a new avenue for in-situ photopolymerization. However, at the device level, surgical endoscopic probes are required. We present a miniaturized light probe where a photoactive material can be 1) mixed, pressurized and injected 2) photopolymerized or photoactivated and 3) monitored during the chemical reaction. The device enables surgeries to be conducted through a hole smaller than 1 mm in diameter. Beside basic injection mechanics, the tool consists of an optical fiber guiding the light required for photopolymerization and for chemical analysis. Combining photorheology and fluorescence spectroscopy, the current state of the photopolymerization is inferred and monitored in real time. Biocompatible and highly tuneable Poly-Ethylene-Glycol (PEG) hydrogels were used as the injection material. The device was tested on a model for intervertebral disc replacement. Gels were successfully implanted into a bovine caudal model and mechanically tested in-vitro during two weeks. The photopolymerized gel was evaluated at the tissue level (adherence and mechanical properties of the implant), at the cellular level (biocompatibility and cytotoxicity) and ergonomic level (sterilization procedure and feasibility study). This paper covers the monitoring aspect of the device.

49 CFR 572.190 - Incorporated materials.

Code of Federal Regulations, 2012 CFR

2012-10-01

... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST DEVICES IIsD Side Impact Crash Test... procedures manual entitled, “Procedures for Assembly, Disassembly, and Inspection (PADI) of the SID-IIsD Side...

49 CFR 572.180 - Incorporated materials.

Code of Federal Regulations, 2013 CFR

2013-10-01

... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST DEVICES ES-2re Side Impact Crash... 50th Percentile Adult Male Side Impact Crash Test Dummy, February 2008,” incorporated by reference in...

49 CFR 572.180 - Incorporated materials.

Code of Federal Regulations, 2014 CFR

2014-10-01

... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST DEVICES ES-2re Side Impact Crash... 50th Percentile Adult Male Side Impact Crash Test Dummy, February 2008,” incorporated by reference in...

40 CFR 63.997 - Performance test and compliance assessment requirements for control devices.

Code of Federal Regulations, 2012 CFR

2012-07-01

... regulated materials are loaded, and samples shall be collected using integrated sampling or grab samples... material concentration and percent reduction may be measured as either total organic regulated material or... regulated material or TOC, sampling sites shall be located as specified in paragraphs (e)(2)(i)(A)(1) and (e...

40 CFR 63.997 - Performance test and compliance assessment requirements for control devices.

Code of Federal Regulations, 2013 CFR

2013-07-01

... regulated materials are loaded, and samples shall be collected using integrated sampling or grab samples... material concentration and percent reduction may be measured as either total organic regulated material or... regulated material or TOC, sampling sites shall be located as specified in paragraphs (e)(2)(i)(A)(1) and (e...

40 CFR 63.997 - Performance test and compliance assessment requirements for control devices.

Code of Federal Regulations, 2014 CFR

2014-07-01

... regulated materials are loaded, and samples shall be collected using integrated sampling or grab samples... material concentration and percent reduction may be measured as either total organic regulated material or... regulated material or TOC, sampling sites shall be located as specified in paragraphs (e)(2)(i)(A)(1) and (e...

Integrated detector array technology for infrared astronomy

NASA Technical Reports Server (NTRS)

Mccreight, c. R.; Goebel, J. H.; Mckelvey, M. E.; Stafford, P. S.; Lee, J. H.

1984-01-01

The status of laboratory and telescope tests of integrated infrared detector array technology for astronomical applications is described. The devices tested represent a number of extrinsic and intrinsic detector materials and various multiplexer designs. Infrared arrays have now been used in successful astronomical applications. These have shown that device sensitivities can be comparable to those of discrete detector systems and excellent astronomical imagery can be produced.

Method and Apparatus for the Portable Identification Of Material Thickness And Defects Along Uneven Surfaces Using Spatially Controlled Heat Application

NASA Technical Reports Server (NTRS)

Reilly, Thomas L. (Inventor); Jacobstein, A. Ronald (Inventor); Cramer, K. Elliott (Inventor)

2006-01-01

A method and apparatus for testing a material such as the water-wall tubes in boilers includes the use of a portable thermal line heater having radiation shields to control the amount of thermal radiation that reaches a thermal imager. A procedure corrects for variations in the initial temperature of the material being inspected. A method of calibrating the testing device to determine an equation relating thickness of the material to temperatures created by the thermal line heater uses empirical data derived from tests performed on test specimens for each material type, geometry, density, specific heat, speed at which the line heater is moved across the material and heat intensity.

Evaluation of Georgia asphalt mixture properties using a Hamburg wheel-tracking device.

DOT National Transportation Integrated Search

2017-05-01

This study used a Hamburg Wheel-Tracking Device (HWTD) to evaluate the resistance of Georgia asphalt mixtures to rutting and stripping. It aimed to develop an HWTD test procedure and criteria aligned with GDOTs asphalt materials and mixture design...

40 CFR 65.158 - Performance test procedures for control devices.

Code of Federal Regulations, 2012 CFR

2012-07-01

... loading period during which regulated materials are loaded, and samples shall be collected using... applicable. The regulated material concentration and percent reduction may be measured as either total regulated material or as TOC (minus methane and ethane) according to the procedures specified. (1) Method 1...

40 CFR 65.158 - Performance test procedures for control devices.

Code of Federal Regulations, 2013 CFR

2013-07-01

... loading period during which regulated materials are loaded, and samples shall be collected using... applicable. The regulated material concentration and percent reduction may be measured as either total regulated material or as TOC (minus methane and ethane) according to the procedures specified. (1) Method 1...

40 CFR 65.158 - Performance test procedures for control devices.

Code of Federal Regulations, 2014 CFR

2014-07-01

... loading period during which regulated materials are loaded, and samples shall be collected using... applicable. The regulated material concentration and percent reduction may be measured as either total regulated material or as TOC (minus methane and ethane) according to the procedures specified. (1) Method 1...

Synthesis and Evaluation of Single Layer, Bilayer, and Multilayer Thermoelectric Thin Films

DOE R&D Accomplishments Database

Farmer, J. C.; Barbee, T. W. Jr.; Chapline, G. C. Jr.; Olsen, M. L.; Foreman, R. J.; Summers, L. J.; Dresselhaus, M. S.; Hicks, L. D.

1995-01-20

The relative efficiency of a thermoelectric material is measured in terms of a dimensionless figure of merit, ZT. Though all known thermoelectric materials are believed to have ZT{le}1, recent theoretical results predict that thermoelectric devices fabricated as two-dimensional quantum wells (2D QWs) or one-dimensional (ID) quantum wires could have ZT{ge}3. Multilayers with the dimensions of 2D QWs have been synthesized by alternately sputtering thermoelectric and barrier materials onto a moving single-crystal sapphire substrate from dual magnetrons. These materials have been used to test the thermoelectric quantum well concept and gain insight into relevant transport mechanisms. If successful, research could lead to thermoelectric devices that have efficiencies close to that of an ideal Carnot engine. Ultimately, such devices could be used to replace conventional heat engines and mechanical refrigeration systems.

Material quality frontiers of MOVPE grown AlGaAs for minority carrier devices

NASA Astrophysics Data System (ADS)

Heckelmann, S.; Lackner, D.; Dimroth, F.; Bett, A. W.

2017-04-01

In this study, secondary ion mass spectroscopy of oxygen, deep level transient spectroscopy and power dependent relative photoluminescence are compared regarding their ability to resolve differences in AlxGa1-xAs material quality. AlxGa1-xAs samples grown with two different trimethylaluminum sources showing low and high levels of oxygen contamination are compared. As tested in the growth of minority carrier devices, i.e. AlxGa1-xAs solar cells, the two precursors clearly lead to different device characteristics. It is shown that secondary ion mass spectroscopy could not resolve the difference in oxygen concentration, whereas deep level transient spectroscopy and photoluminescence based measurements indicate the influence of the precursor oxygen level on the material quality.

Fracture Tests of Etched Components Using a Focused Ion Beam Machine

NASA Technical Reports Server (NTRS)

Kuhn, Jonathan, L.; Fettig, Rainer K.; Moseley, S. Harvey; Kutyrev, Alexander S.; Orloff, Jon; Powers, Edward I. (Technical Monitor)

2000-01-01

Many optical MEMS device designs involve large arrays of thin (0.5 to 1 micron components subjected to high stresses due to cyclic loading. These devices are fabricated from a variety of materials, and the properties strongly depend on size and processing. Our objective is to develop standard and convenient test methods that can be used to measure the properties of large numbers of witness samples, for every device we build. In this work we explore a variety of fracture test configurations for 0.5 micron thick silicon nitride membranes machined using the Reactive Ion Etching (RIE) process. Testing was completed using an FEI 620 dual focused ion beam milling machine. Static loads were applied using a probe. and dynamic loads were applied through a piezo-electric stack mounted at the base of the probe. Results from the tests are presented and compared, and application for predicting fracture probability of large arrays of devices are considered.

Implementation of testing equipment for asphalt materials.

DOT National Transportation Integrated Search

2009-05-01

Three new automated methods for related asphalt testing were evaluated under this study in an effort to save time and reduce variability in testing. The Therymolyne SSDetect, Instrotek CoreLok and Instrotek CoreDry devices were evaluated throughout t...

Implementation of Testing Equipment for Asphalt Materials

DOT National Transportation Integrated Search

2009-05-01

Three new automated methods for related asphalt testing were evaluated under this study in an effort to save time and reduce variability in testing. The Therymolyne SSDetect, Instrotek CoreLok and Instrotek CoreDry devices were evaluated throughout t...

Study of materials for space processing

NASA Technical Reports Server (NTRS)

Lal, R. B.

1975-01-01

Materials were selected for device applications and their commercial use. Experimental arrangements were also made for electrical characterization of single crystals using electrical resistivity and Hall effect measurements. The experimental set-up was tested with some standard samples.

Biodetection grinder

NASA Technical Reports Server (NTRS)

Beyerle, F. J.

1973-01-01

A biodetection grinder for sampling aerospace materials for microorganisms without killing them was constructed. The device employs a shearing action to generate controllable sized particles with a minimum of energy input. Tests were conducted on materials ranging from soft plastics to hard rocks.

Soft x ray window encapsulant for HgI2 detectors

NASA Technical Reports Server (NTRS)

Entine, G.; Shah, K.; Squillante, M.

1987-01-01

HgI2 is an excellent semiconductor material for a low energy, room temperature x-ray spectrometer. The high values of the atomic numbers for its constituent elements gives high x-ray and gamma ray stopping power. The band gap of HgI2 is significantly higher than other commonly used semiconductors. Owing to the large value band gap, the leakage current for HgI2 devices is smaller, thus allowing low noise performance. Devices fabricated from HgI2 crystals have demonstrated energy resolution sufficient to distinguish the x-ray emission from the neighboring elements on the periodic table. Also the power requirements of HgI2 are very low. These characteristics make a HgI2 spectrometer an ideal component in a satellite based detection system. Unfortunately, HgI2 crystals tend to deteriorate with time, even if protected by standard semiconductor encapsulants. This degradation ruins the performance of the device in terms of its energy resolution and pulse amplitude. The degrading mechanism is believed to be material loss occurring from below the electrodes, due to high vapor pressure of HgI2 at room temperature. To address this major obstacle to rapid expansion of HgI2 technology, a research program aimed at improving device stability by encapsulation with inert polymeric materials was carried out. The program focused specifically on optimizing the encapsulant materials and their deposition techniques. The principal objectives for this program were device encapsulation, device testing, and accelerated testing to ensure very long term stability of these high resolution sensors. A variety of encapsulants were investigated with the selection criteria based on their chemical diffusion barrier properties, mechanical stability, reactivity, and morphology of encapsulant films. The investigation covered different classes of encapsulants including solvent based encapsulants, vapor deposited encapsulants, and plasma polymerized encapsulants. A variety of characterization techniques were employed to examine their effectiveness in stabilizing HgI2 devices; these included permeability evaluation, vacuum and heat testing, scanning electron microscopy (SEM) as well as studying the detector performance of coated detectors. The plasma polymerized films appear to have entirely solved the HgI2 degradation problem. Another achievement of this program was the development of an accelerated testing technique which correlates extremely well with long term tesing.

Ultrasonic monitoring of the setting of silicone elastomeric impression materials.

PubMed

Kanazawa, Tomoe; Murayama, Ryosuke; Furuichi, Tetsuya; Imai, Arisa; Suda, Shunichi; Kurokawa, Hiroyasu; Takamizawa, Toshiki; Miyazaki, Masashi

2017-01-31

This study used an ultrasonic measurement device to monitor the setting behavior of silicone elastomeric impression materials, and the influence of temperature on setting behavior was determined. The ultrasonic device consisted of a pulser-receiver, transducers, and an oscilloscope. The two-way transit time through the mixing material was divided by two to account for the down-and-back travel path; then it was multiplied by the sonic velocity. Analysis of variance and the Tukey honest significant difference test were used. In the early stages of the setting process, most of the ultrasonic energy was absorbed by the elastomers and the second echoes were relatively weak. As the elastomers hardened, the sonic velocities increased until they plateaued. The changes in sonic velocities varied among the elastomers tested, and were affected by temperature conditions. The ultrasonic method used in this study has considerable potential for determining the setting processes of elastomeric impression materials.

Type of motion and lubricant in wear simulation of polyethylene acetabular cup.

PubMed

Saikko, V; Ahlroos, T

1999-01-01

The wear of ultra-high molecular weight polyethylene, the most commonly used bearing material in prosthetic joints, is often substantial, posing a significant clinical problem. For a long time, there has been a need for simple but still realistic wear test devices for prosthetic joint materials. The wear factors produced by earlier reciprocating and unidirectionally rotating wear test devices for polyethylene are typically two orders of magnitude too low, both in water and in serum lubrication. Wear is negligible even under multidirectional motion in water. A twelve-station, circularly translating pin-on-disc (CTPOD) device and a modification of the established biaxial rocking motion hip joint simulator were built. With these simple and inexpensive devices, and with the established three-axis hip joint simulator, realistic wear simulation was achieved. This was due to serum lubrication and to the fact that the direction of sliding constantly changed relative to the polyethylene specimen. The type and magnitude of load was found to be less important. The CTPOD tests showed that the subsurface brittle region, which results from gamma irradiation sterilization of polyethylene in air, has poor wear resistance. Phospholipid and soy protein lubrication resulted in unrealistic wear. The introduction of devices like CTPOD may boost wear studies, rendering them feasible without heavy investment.

The use of polyurethane materials in the surgery of the spine: a review.

PubMed

St John, Kenneth R

2014-12-01

The spine contains intervertebral discs and the interspinous and longitudinal ligaments. These structures are elastomeric or viscoelastic in their mechanical properties and serve to allow and control the movement of the bony elements of the spine. The use of metallic or hard polymeric devices to replace the intervertebral discs and the creation of fusion masses to replace discs and/or vertebral bodies changes the load transfer characteristics of the spine and the range of motion of segments of the spine. The purpose of the study was to survey the literature, regulatory information available on the Web, and industry-reported device development found on the Web to ascertain the usage and outcomes of the use of polyurethane polymers in the design and clinical use of devices for spine surgery. A systematic review of the available information from all sources concerning the subject materials' usage in spinal devices was conducted. A search of the peer-reviewed literature combining spinal surgery with polyurethane or specific types and trade names of medical polyurethanes was performed. Additionally, information available on the Food and Drug Administration Web site and for corporate Web sites was reviewed in an attempt to identify pertinent information. The review captured devices that are in testing or have entered clinical practice that use elastomeric polyurethane polymers as disc replacements, dynamic stabilization of spinal movement, or motion limitation to relieve nerve root compression and pain and as complete a listing as possible of such devices that have been designed or tested but appear to no longer be pursued. This review summarizes the available information about the uses to which polyurethanes have been tested or are being used in spinal surgery. The use of polyurethanes in medicine has expanded as modifications to the stability of the polymers in the physiological environment have been improved. The potential for the use of elastomeric materials to more closely match the mechanical properties of the structures being replaced and to maintain motion between spinal segments appears to hold promise. The published results from the use of the devices that are discussed show early success with these applications of elastomeric materials. Copyright © 2014 Elsevier Inc. All rights reserved.

40 CFR 63.694 - Testing methods and procedures.

Code of Federal Regulations, 2010 CFR

2010-07-01

... material stream shall be collected from the container, pipeline, or other device used to deliver the off... off-site material streams at the point-of-delivery for compliance with standards specified § 63.683 of... determine the average VOHAP concentration for treated off-site material streams at the point-of-treatment...

78 FR 25723 - National Assessment Governing Board; Meeting

Federal Register 2010, 2011, 2012, 2013, 2014

2013-05-02

..., assistive listening devices, materials in alternative format) should notify Munira Mwalimu at 202- 357-6938.... to review secure NAEP test materials for Science Interactive Computer Tasks (ICTs) at grades 4, 8... provided with secure items and materials which are not yet available for release to the general public...

End of FY2014 Report - Filter Measurement System for Nuclear Material Storage Canisters (Including Altitude Correction for Filter Pressure Drop)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Moore, Murray E.; Reeves, Kirk Patrick

2015-02-24

Two LANL FTS (Filter Test System ) devices for nuclear material storage canisters are fully operational. One is located in PF-4 ( i.e. the TA-55 FTS) while the other is located at the Radiation Protection Division’s Aerosol Engineering Facility ( i.e. the TA-3 FTS). The systems are functionally equivalent , with the TA-3 FTS being the test-bed for new additions and for resolving any issues found in the TA-55 FTS. There is currently one unresolved issue regarding the TA-55 FTS device. The canister lid clamp does not give a leak tight seal when testing the 1 QT (quart) or 2more » QT SAVY lids. An adapter plate is being developed that will ensure a correct test configuration when the 1 or 2 QT SAVY lid s are being tested .« less

Materials sciences research. [research facilities, research projects, and technical reports of materials tests

NASA Technical Reports Server (NTRS)

1973-01-01

Research projects involving materials research conducted by various international test facilities are reported. Much of the materials research is classified in the following areas: (1) acousto-optic, acousto-electric, and ultrasonic research, (2) research for elucidating transport phenomena in well characterized oxides, (3) research in semiconductor materials and semiconductor devices, (4) the study of interfaces and interfacial phenomena, and (5) materials research relevant to natural resources. Descriptions of the individual research programs are listed alphabetically by the name of the author and show all personnel involved, resulting publications, and associated meeting speeches.

49 CFR 572.40 - Incorporated materials.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 7 2013-10-01 2013-10-01 false Incorporated materials. 572.40 Section 572.40 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST DEVICES Side Impact Dummy 50th...

49 CFR 572.110 - Materials incorporated by reference.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 7 2014-10-01 2014-10-01 false Materials incorporated by reference. 572.110 Section 572.110 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST DEVICES Side...

49 CFR 572.40 - Incorporated materials.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 49 Transportation 7 2014-10-01 2014-10-01 false Incorporated materials. 572.40 Section 572.40 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST DEVICES Side Impact Dummy 50th...

49 CFR 572.110 - Materials incorporated by reference.

Code of Federal Regulations, 2013 CFR

2013-10-01

... 49 Transportation 7 2013-10-01 2013-10-01 false Materials incorporated by reference. 572.110 Section 572.110 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST DEVICES Side...

49 CFR 572.40 - Incorporated materials.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 7 2012-10-01 2012-10-01 false Incorporated materials. 572.40 Section 572.40 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST DEVICES Side Impact Dummy 50th...

49 CFR 572.110 - Materials incorporated by reference.

Code of Federal Regulations, 2012 CFR

2012-10-01

... 49 Transportation 7 2012-10-01 2012-10-01 false Materials incorporated by reference. 572.110 Section 572.110 Transportation Other Regulations Relating to Transportation (Continued) NATIONAL HIGHWAY TRAFFIC SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST DEVICES Side...

Medical devices; ovarian adnexal mass assessment score test system; labeling; black box restrictions. Final rule.

PubMed

2011-12-30

The Food and Drug Administration (FDA) is amending the regulation classifying ovarian adnexal mass assessment score test systems to restrict these devices so that a prescribed warning statement that addresses a risk identified in the special controls guidance document must be in a black box and must appear in all labeling, advertising, and promotional material. The black box warning mitigates the risk to health associated with off-label use as a screening test, stand-alone diagnostic test, or as a test to determine whether or not to proceed with surgery.

MBE HgCdTe for HDVIP Devices: Horizontal Integration in the US HgCdTe FPA Industry

NASA Astrophysics Data System (ADS)

Aqariden, F.; Elsworth, J.; Zhao, J.; Grein, C. H.; Sivananthan, S.

2012-10-01

Molecular beam epitaxy (MBE) growth of HgCdTe offers the possibility of fabricating multilayer device structures with an almost unlimited choice of infrared sensor designs for focal-plane array (FPA) fabrication. HgCdTe offers two major advantages that explain its dominance in the infrared photon detector marketplace. The thermal generation rate per unit volume of the material is lower and the quantum efficiency for photon absorption in the infrared is higher in HgCdTe than in any competing material—it yields devices with quantum efficiencies as high as 0.99. Recently, EPIR Technologies and DRS Infrared Technologies agreed to collaborate and examine: (i) the feasibility of employing MBE HgCdTe in the fabrication of high-density vertically interconnected photodiodes (HDVIPs), which are usually fabricated with liquid-phase epitaxy material, and (ii) the potential benefits of horizontal integration, with EPIR supplying the MBE materials to DRS for device and array fabrication. The team designed and developed passivation-absorber-passivation structures that are heavily used by DRS. This paper provides an overview of the characteristics of HDVIP devices and arrays fabricated from MBE HgCdTe and the anticipated advantages of horizontal integration in the industry. Material growth, device fabrication, and test results are presented.

Ultrafast Spectroscopic Noninvasive Probe of Vertical Carrier Transport in Heterostructure Devices (Second year of three year progress report)

DTIC Science & Technology

2014-10-01

properties in Army-relevant semiconductor materials and optoelectronic ( OE ) devices by developing and applying ultrafast optical spectroscopy techniques...met our Q6 through Q8 goals of incorporating electrical testing capabilities into our system, investigating OE devices under operating conditions...extending the capabilities of our system into the IR range, and investigating new OE devices. We have made significant progress towards our Q5 goal of

Viscoelastic coupling of nanoelectromechanical resonators.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Simonson, Robert Joseph; Staton, Alan W.

2009-09-01

This report summarizes work to date on a new collaboration between Sandia National Laboratories and the California Institute of Technology (Caltech) to utilize nanoelectromechanical resonators designed at Caltech as platforms to measure the mechanical properties of polymeric materials at length scales on the order of 10-50 nm. Caltech has succeeded in reproducibly building cantilever resonators having major dimensions on the order of 2-5 microns. These devices are fabricated in pairs, with free ends separated by reproducible gaps having dimensions on the order of 10-50 nm. By controlled placement of materials that bridge the very small gap between resonators, the mechanicalmore » devices become coupled through the test material, and the transmission of energy between the devices can be monitored. This should allow for measurements of viscoelastic properties of polymeric materials at high frequency over short distances. Our work to date has been directed toward establishing this measurement capability at Sandia.« less

A new prosthesis for the metacarpophalangeal joint. Study of materials and biomechanics.

PubMed

Petrolati, M; Abbiati, G; Delaria, G; Soffiatti, R; Robotti, P; Guerriero, C

1999-02-01

This report discusses the Daphne prosthesis for the metacarpophalangeal joint on the basis of the mechanical, chemical and biological performance of the materials employed. The Daphne prosthesis is a mobile device. The main body is made of a new generation polymethylmetacrylate, while the hinge is made of AISI 316 L stainless steel. Biocompatibility tests were performed on the materials employed. Systemic toxicity, cytotoxicity and contact tests have given favourable results. Mechanical engineering tests have been used to investigate the performances and reliability of the selected materials. The polymethylmetacrylate used in Daphne behaves in a ductile fashion. No mechanical failures were encountered in fatigue tests after 10 million cycles.

Characterization of Vertical Impact Device Acceleration Pulses Using Parametric Assessment: Phase IV Dual Impact Pulses

DTIC Science & Technology

2017-01-04

response, including the time for reviewing instructions, searching existing data sources, searching existing data sources, gathering and maintaining...configurations with a restrained manikin, was evaluated in four different test series . Test Series 1 was conducted to determine the materials and...5 ms TTP. Test Series 2 was conducted to determine the materials and drop heights required for energy attenuation of the seat pan to generate a 4 m

Investigating Dielectric and Metamaterial Effects in a Terahertz Traveling-Wave Tube Amplifier

NASA Technical Reports Server (NTRS)

Starinshak, David P.; Wilson, Jeffrey D.

2008-01-01

Adding material enhancements to a terahertz traveling-wave tube amplifier is investigated. Isotropic dielectrics, negative-index metamaterials, and anisotropic crystals are simulated, and plans to increase the efficiency of the device are discussed. Early results indicate that adding dielectric to the curved sections of the serpentine-shaped slow-wave circuit produce optimal changes in the cold-test characteristics of the device and a minimal drop in operating frequency. Additional results suggest that materials with simultaneously small relative permittivities and electrical conductivities are best suited for increasing the efficiency of the device. More research is required on the subject, and recommendations are given to determine the direction.

Laser-machined piezoelectric cantilevers for mechanical energy harvesting.

PubMed

Kim, HyunUk; Bedekar, Vishwas; Islam, Rashed Adnan; Lee, Woo-Ho; Leo, Don; Priya, Shashank

2008-09-01

In this study, we report results on a piezoelectric- material-based mechanical energy-harvesting device that was fabricated by combining laser machining with microelectronics packaging technology. It was found that the laser-machining process did not have significant effect on the electrical properties of piezoelectric material. The fabricated device was tested in the low-frequency regime of 50 to 1000 Hz at constant force of 8 g (where g = 9.8 m/s(2)). The device was found to generate continuous power of 1.13 microW at 870 Hz across a 288.5 kOmega load with a power density of 301.3 microW/cm(3).

21 CFR 882.1925 - Ultrasonic scanner calibration test block.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Ultrasonic scanner calibration test block. 882... Ultrasonic scanner calibration test block. (a) Identification. An ultrasonic scanner calibration test block is a block of material with known properties used to calibrate ultrasonic scanning devices (e.g., the...

Testing methods and techniques: Environmental testing: A compilation

NASA Technical Reports Server (NTRS)

1971-01-01

Various devices and techniques are described for testing hardware and components in four special environments: low temperature, high temperature, high pressure, and vibration. Items ranging from an automatic calibrator for pressure transducers to a fixture for testing the susceptibility of materials to ignition by electric spark are included.

Handbook for Driving Knowledge Testing.

ERIC Educational Resources Information Center

Pollock, William T.; McDole, Thomas L.

Materials intended for driving knowledge test development for use by operational licensing and education agencies are presented. A pool of 1,313 multiple choice test items is included, consisting of sets of specially developed and tested items covering principles of safe driving, legal regulations, and traffic control device knowledge pertinent to…

49 CFR Appendix D to Part 178 - Thermal Resistance Test

Code of Federal Regulations, 2013 CFR

2013-10-01

... large enough in size to fully house the test outer package without clearance problems. The test oven....3Instrumentation. A calibrated recording device or a computerized data acquisition system with an appropriate range... Configuration. Each outer package material type and design must be tested, including any features such as...

49 CFR Appendix D to Part 178 - Thermal Resistance Test

Code of Federal Regulations, 2014 CFR

2014-10-01

... large enough in size to fully house the test outer package without clearance problems. The test oven....3Instrumentation. A calibrated recording device or a computerized data acquisition system with an appropriate range... Configuration. Each outer package material type and design must be tested, including any features such as...

49 CFR Appendix D to Part 178 - Thermal Resistance Test

Code of Federal Regulations, 2011 CFR

2011-10-01

... large enough in size to fully house the test outer package without clearance problems. The test oven....3Instrumentation. A calibrated recording device or a computerized data acquisition system with an appropriate range... Configuration. Each outer package material type and design must be tested, including any features such as...

49 CFR Appendix D to Part 178 - Thermal Resistance Test

Code of Federal Regulations, 2012 CFR

2012-10-01

... large enough in size to fully house the test outer package without clearance problems. The test oven....3Instrumentation. A calibrated recording device or a computerized data acquisition system with an appropriate range... Configuration. Each outer package material type and design must be tested, including any features such as...

Fused Deposition Modeling 3D Printing for (Bio)analytical Device Fabrication: Procedures, Materials, and Applications

PubMed Central

2017-01-01

In this work, the use of fused deposition modeling (FDM) in a (bio)analytical/lab-on-a-chip research laboratory is described. First, the specifications of this 3D printing method that are important for the fabrication of (micro)devices were characterized for a benchtop FDM 3D printer. These include resolution, surface roughness, leakage, transparency, material deformation, and the possibilities for integration of other materials. Next, the autofluorescence, solvent compatibility, and biocompatibility of 12 representative FDM materials were tested and evaluated. Finally, we demonstrate the feasibility of FDM in a number of important applications. In particular, we consider the fabrication of fluidic channels, masters for polymer replication, and tools for the production of paper microfluidic devices. This work thus provides a guideline for (i) the use of FDM technology by addressing its possibilities and current limitations, (ii) material selection for FDM, based on solvent compatibility and biocompatibility, and (iii) application of FDM technology to (bio)analytical research by demonstrating a broad range of illustrative examples. PMID:28628294

Evaluation of the biocompatibility of a coating material for an implantable bladder volume sensor.

PubMed

Kim, Su-Jin; Lee, Dong-Sup; Kim, In-Gul; Sohn, Dong-Wan; Park, Jung-Yul; Choi, Bum-Kyoo; Kim, Sae-Woong

2012-03-01

As the applications for implantable medical devices have increased, the need for biocompatible packaging materials has become important. Recently, we reported an implantable sensor for real-time monitoring of the changes in bladder volume, which necessitated finding a safe coating material for use in bladder tissue. At present, materials like polyethylene glycol (PEG), polydimethylsiloxane (PDMS) and parylene-C are used in biomedical devices or as coating materials, owing to their excellent safety in various medical fields. However, few studies have assessed their safety in bladder tissue, therefore, we evaluated the biocompatibility of PEG, PDMS and parylene-C in the bladder. All three materials turned out to be safe in in vitro tests of live/dead staining and cell viability. In vivo tests with hematoxylin and eosin and immunofluorescence staining with MAC387 showed no persistent inflammation. Therefore, we consider that the three materials are biocompatible in bladder tissue. Despite this safety, however, PEG has biodegradable characteristics and thus is not suitable for use as packaging. We suggest that PDMS and parylene-C can be used as safe coating materials for the implantable bladder volume sensor reported previously. Copyright © 2012. Published by Elsevier B.V.

Vibration reduction on automotive shafts using piezoceramics

NASA Astrophysics Data System (ADS)

Kunze, Holger; Riedel, Mathias; Schmidt, Knut; Bianchini, Emanuele

2003-08-01

This paper reports an experimental study on active vibration reduction for automotive shafts with the use of piezoelectric material. The work focuses on an axle of an Audi A2. The demand in the automobile sector for higher comfort in the vehicle is of a great importance alongside the requirements of lighter weight and low fuel consumption. These requirements are typically in conflict with each other. One solution is the use of intelligent materials instead of viscoelastic materials and proof mass absorbers. These solutions are quite heavy especially at low frequencies. Active vibration control and piezoelectric devices are advantageous in this application due to their low mass to performance ratio. Our research study explores the use of such piezoelectric devices for an axle. In conjunction with electronics it will reduce vibrations in the first natural bending mode of the axle. Laboratory tests simulated the condition present in the road. At first a stationary set up was used, then a simulated disturbance was input at the attachment points of the shaft. Finally, a test with rotating shaft was performed. Piezoelectric devices (custom QuickPacks from ACX, a Division of Cymer) were used as sensors and as actuators to properly control the axle during the different operating conditions. The power consumption of each actuator pair was less than 20W. The work described here details the test setup, the control strategy, the hardware implementation as well as the test results obtained.

46 CFR 164.023-11 - Acceptance tests.

Code of Federal Regulations, 2014 CFR

2014-10-01

... 46 Shipping 6 2014-10-01 2014-10-01 false Acceptance tests. 164.023-11 Section 164.023-11 Shipping...: SPECIFICATIONS AND APPROVAL MATERIALS Thread for Personal Flotation Devices § 164.023-11 Acceptance tests. (a) Performance testing. Manufacturers shall ensure that the performance tests described in § 164.023-7 (a) or (b...

Electromagnetic radiation screening of microcircuits for long life applications

NASA Technical Reports Server (NTRS)

Brammer, W. G.; Erickson, J. J.; Levy, M. E.

1974-01-01

The utility of X-rays as a stimulus for screening high reliability semiconductor microcircuits was studied. The theory of the interaction of X-rays with semiconductor materials and devices was considered. Experimental measurements of photovoltages, photocurrents, and effects on specified parameters were made on discrete devices and on microcircuits. The test specimens included discrete devices with certain types of identified flaws and symptoms of flaws, and microcircuits exhibiting deviant electrical behavior. With a necessarily limited sample of test specimens, no useful correlation could be found between the X-ray-induced electrical response and the known or suspected presence of flaws.

The FDA role in contact lens development and safety.

PubMed

Lippman, R E

1990-01-01

The Food and Drug Administration (FDA) exercises a multifaceted role in fulfilling its mission of enforcing the Federal Food, Drug and Cosmetic Act (Act), functioning not only as industry regulator and consumer protector, but also as scientific advisor and consumer educator regarding medical devices, drugs, foods, cosmetics, and veterinary medicine. Medical devices are regulated within the Center for Devices and Radiological Health. Contact lenses are regulated under the authority of the medical device amendments. The Center is responsible for promulgating regulations, publishing guidelines, and developing written guidance in enforcing the Act, and also for guiding manufacturers of medical devices in safe and effective product development. Other components deal with the compliance of manufacturers with the marketing of medical devices within the meaning of the Act, and through labeling requirements of the Act and consumer education and informational activities. As for contact lenses, the process of updating product development regulations and guidelines is an ongoing activity. The most recent version of the Contact Lens Guideline Document, issued in April 1988, contains two major revisions involving preclinical and clinical testing. The first redefines plastics into one materials category, thus reducing testing requirements with respect to animal toxicology studies and other preclinical areas. The second revision restricts clinical testing requirements to allow confirmatory trials in applications for new daily wear lenses. The intention was to maintain the ability of studies to detect major material or design flaws in lenses, thus boosting confidence in their performance while eliminating unnecessary trials.(ABSTRACT TRUNCATED AT 250 WORDS)

LEO Flight Testing of GaAs on Si Solar Cells Aboard MISSES

NASA Technical Reports Server (NTRS)

Wilt, David M.; Clark, Eric B.; Ringel, Steven A.; Andre, Carrie L.; Smith, Mark A.; Scheiman, David A.; Jenkins, Phillip P.; Maurer, William F.; Fitzgerald, Eugene A.; Walters, R. J.

2004-01-01

Previous research efforts have demonstrated small area (0.04 cm) GaAs on Si (GaAs/Si) solar cells with AM0 efficiencies in excess of 17%. These results were achieved on Si substrates coated with a step graded buffer of Si(x),Ge(1-x) alloys graded to 100% Ge. Recently, a 100-fold increase in device area was accomplished for these devices in preparation for on-orbit testing of this technology aboard Materials International Space Station Experiment number 5 (MISSE5). The GaAs/Si MISSE5 experiment contains five (5) GaAs/Si test devices with areas of lcm(exp 2) and 4cm(exp 4) as well as two (2) GaAs on GaAs control devices. Electrical performance data, measured on-orbit for three (3) of the test devices and one (1) of the control devices, will be telemetered to ground stations daily. After approximately one year on orbit, the MISSE5 payload will be returned to Earth for post flight evaluation. This paper will discuss the development of the GaAs/Si devices for the MISSE5 flight experiment and will present recent ground and on-orbit performance data.

a Brief Survey on Basic Properties of Thin Films for Device Application

NASA Astrophysics Data System (ADS)

Rao, M. C.; Shekhawat, M. S.

Thin film materials are the key elements of continued technological advances made in the fields of optoelectronic, photonic and magnetic devices. Thin film studies have directly or indirectly advanced many new areas of research in solid state physics and chemistry which are based on phenomena uniquely characteristic of the thickness, geometry and structure of the film. The processing of materials into thin films allows easy integration into various types of devices. Thin films are extremely thermally stable and reasonably hard, but they are fragile. On the other hand organic materials have reasonable thermal stability and are tough, but are soft. Thin film mechanical properties can be measured by tensile testing of freestanding films and by the micro beam cantilever deflection technique, but the easiest way is by means of nanoindentation. Optical experiments provide a good way of examining the properties of semiconductors. Particularly measuring the absorption coefficient for various energies gives information about the band gaps of the material. Thin film materials have been used in semiconductor devices, wireless communications, telecommunications, integrated circuits, rectifiers, transistors, solar cells, light-emitting diodes, photoconductors and light crystal displays, lithography, micro- electromechanical systems (MEMS) and multifunctional emerging coatings, as well as other emerging cutting technologies.

Influence of copper composition on mechanical properties of biodegradable material Mg-Zn-Cu for orthopedic application

NASA Astrophysics Data System (ADS)

Purniawan, A.; Maulidiah, H. M.; Purwaningsih, H.

2018-04-01

Implant is usually used as a treatment of bone fracture. At the moment, non-biodegradable implants is still widely employed in this application. Non-biodegradable implant requires re-surgery to retrieve implants that are installed in the body. It increase the cost and it is painful for the patient itself. In order to solve the problem, Mg-based biodegradable metals is developing so that the material will be compatible with body and gradually degrade in patient's body. However, magnesium has several disadvantages such as high degradation rates and low mechanical properties when compared to the mechanical properties of natural bone. Therefore, it is necessary to add elements into the magnesium alloy. In this research, copper (Cu) was alloyed in Mg alloy based biodegradable material. In addition, Cu is not only strengthening the structure but also for supporting element for the immune system, antibacterial and antifungal. The purpose of this research is to improve mechanical properties of Mg-based biodegradable material using Cu alloying. Powder metallurgy method was used to fabricate the device. The variation used in this research is the composition of Cu (0.5, 1, and 1.5% Cu). The porosity test was performed using apparent porosity test, compressive test and hardness test to know the mechanical properties of the alloy, and the weightless test to find out the material degradation rate. Based on the results can be conclude that Mg-Zn-Cu alloy material with 1% Cu composition is the most suitable specimen to be applied as a candidate for orthopedic devices material with hardness value is 393.6 MPa. Also obtained the value of the compressive test is 153 MPa.

Characterising the material properties at the interface between skin and a skin vaccination microprojection device.

PubMed

Crichton, Michael L; Archer-Jones, Cameron; Meliga, Stefano; Edwards, Grant; Martin, Darren; Huang, Han; Kendall, Mark A F

2016-05-01

The rapid emergence of micro-devices for biomedical applications over the past two decades has introduced new challenges for the materials used in the devices. Devices like microneedles and the Nanopatch, require sufficient strength to puncture skin often with sharp-slender micro-scale profiles, while maintaining mechanical integrity. For these technologies we sought to address two important questions: 1) On the scale at which the device operates, what forces are required to puncture the skin? And 2) What loads can the projections/microneedles withstand prior to failure. First, we used custom fabricated nanoindentation micro-probes to puncture skin at the micrometre scale, and show that puncture forces are ∼0.25-1.75mN for fresh mouse skin, in agreement with finite element simulations for our device. Then, we used two methods to perform strength tests of Nanopatch projections with varied aspect ratios. The first method used a nanoindenter to apply a force directly on the top or on the side of individual silicon projections (110μm in length, 10μm base radius), to measure the force of fracture. Our second method used an Instron to fracture full rows of projections and characterise a range of projection designs (with the method verified against previous nanoindentation experiments). Finally, we used Cryo-Scanning Electron Microscopy to visualise projections in situ in the skin to confirm the behaviour we quantified, qualitatively. Micro-device development has proliferated in the past decade, including devices that interact with tissues for biomedical outcomes. The field of microneedles for vaccine delivery to skin has opened new material challenges both in understanding tissue material properties and device material. In this work we characterise both the biomaterial properties of skin and the material properties of our microprojection vaccine delivery device. This study directly measures the micro-scale puncture properties of skin, whilst demonstrating clearly how these relate to device design. This will be of strong interest to those in the field of biomedical microdevices. This includes work in the field of wearable and semi-implantable devices, which will require clear understanding of tissue behaviour and material characterisation. Copyright © 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Design optimization of beta- and photovoltaic conversion devices

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wichner, R.; Blum, A.; Fischer-Colbrie, E.

1976-01-08

This report presents the theoretical and experimental results of an LLL Electronics Engineering research program aimed at optimizing the design and electronic-material parameters of beta- and photovoltaic p-n junction conversion devices. To meet this objective, a comprehensive computer code has been developed that can handle a broad range of practical conditions. The physical model upon which the code is based is described first. Then, an example is given of a set of optimization calculations along with the resulting optimized efficiencies for silicon (Si) and gallium-arsenide (GaAs) devices. The model we have developed, however, is not limited to these materials. Itmore » can handle any appropriate material--single or polycrystalline-- provided energy absorption and electron-transport data are available. To check code validity, the performance of experimental silicon p-n junction devices (produced in-house) were measured under various light intensities and spectra as well as under tritium beta irradiation. The results of these tests were then compared with predicted results based on the known or best estimated device parameters. The comparison showed very good agreement between the calculated and the measured results.« less

Methods of Measurement for Semiconductor Materials, Process Control, and Devices

NASA Technical Reports Server (NTRS)

Bullis, W. M. (Editor)

1973-01-01

The development of methods of measurement for semiconductor materials, process control, and devices is reported. Significant accomplishments include: (1) Completion of an initial identification of the more important problems in process control for integrated circuit fabrication and assembly; (2) preparations for making silicon bulk resistivity wafer standards available to the industry; and (3) establishment of the relationship between carrier mobility and impurity density in silicon. Work is continuing on measurement of resistivity of semiconductor crystals; characterization of generation-recombination-trapping centers, including gold, in silicon; evaluation of wire bonds and die attachment; study of scanning electron microscopy for wafer inspection and test; measurement of thermal properties of semiconductor devices; determination of S-parameters and delay time in junction devices; and characterization of noise and conversion loss of microwave detector diodes.

46 CFR 160.064-6 - Examinations, tests and inspections.

Code of Federal Regulations, 2010 CFR

2010-10-01

... labeled water safety buoyant devices shall maintain quality control of the materials used, manufacturing... available to the recognized laboratory inspector or to the Coast Guard marine inspector, or both, for review upon request. (b) Laboratory inspections and tests. Such examinations, inspections and tests as are...

10 CFR 71.125 - Control of measuring and test equipment.

Code of Federal Regulations, 2010 CFR

2010-01-01

... MATERIAL Quality Assurance § 71.125 Control of measuring and test equipment. The licensee, certificate holder, and applicant for a CoC shall establish measures to assure that tools, gauges, instruments, and other measuring and testing devices used in activities affecting quality are properly controlled...

Compression testing of flammable liquids

NASA Technical Reports Server (NTRS)

Briles, O. M.; Hollenbaugh, R. P.

1979-01-01

Small cylindrical test chamber determines catalytic effect of given container material on fuel that might contribute to accidental deflagration or detonation below expected temperature under adiabatic compression. Device is useful to producers and users of flammable liquids and to safety specialists.

Single crystal metal wedges for surface acoustic wave propagation

DOEpatents

Fisher, E.S.

1980-05-09

An ultrasonic testing device has been developed to evaluate flaws and inhomogeneities in the near-surface region of a test material. A metal single crystal wedge is used to generate high frequency Rayleigh surface waves in the test material surface by conversion of a slow velocity, bulk acoustic mode in the wedge into a Rayleigh wave at the metal-wedge test material interface. Particular classes of metals have been found to provide the bulk acoustic modes necessary for production of a surface wave with extremely high frequency and angular collimation. The high frequency allows flaws and inhomogeneities to be examined with greater resolution. The high degree of angular collimation for the outgoing ultrasonic beam permits precision angular location of flaws and inhomogeneities in the test material surface.

Single crystal metal wedges for surface acoustic wave propagation

DOEpatents

Fisher, Edward S.

1982-01-01

An ultrasonic testing device has been developed to evaluate flaws and inhomogeneities in the near-surface region of a test material. A metal single crystal wedge is used to generate high frequency Rayleigh surface waves in the test material surface by conversion of a slow velocity, bulk acoustic mode in the wedge into a Rayleigh wave at the metal-wedge test material interface. Particular classes of metals have been found to provide the bulk acoustic modes necessary for production of a surface wave with extremely high frequency and angular collimation. The high frequency allows flaws and inhomogeneities to be examined with greater resolution. The high degree of angular collimation for the outgoing ultrasonic beam permits precision angular location of flaws and inhomogeneities in the test material surface.

Decontaminating materials used in ground water sampling devices: Organic contaminants

DOE Office of Scientific and Technical Information (OSTI.GOV)

Parker, L.V.; Ranney, T.A.

2000-12-31

In these studies, the efficiency of various decontamination protocols was tested on small pieces of materials commonly used in ground water sampling devices. Three materials, which ranged in ability to sorb organic solutes, were tested: stainless steel (SS), rigid polyvinyl chloride (PVC), and polytetrafluoroethylene (PTFE). The test pieces were exposed to two aqueous test solutions: One contained three volatile organic compounds (VOCs) and one nitroaromatic compound, and the other contained four pesticides. Also, three types of polymetic tubing were exposed to pesticide solutions. Generally, the contact times were 10 minutes and 24 hours for sorption and desorption. The contaminants weremore » removed from the nonpermeable SS and the less-sorptive rigid PVC test pieces simply by washing with a hot detergent solution and rinsing with hot water. Additional treatment was required for the PTFE test pieces exposed to the VOCs and for the low-density polyethylene (LDPE) tubing exposed to the pesticide test solution. Solvent rinsing did not improve removal of the three VOCs form the PTFE and only marginally improved removal of the residual pesticides from the LDPE. However, a hot water and detergent wash and rinse followed by oven drying at approximately 105 C was effective for removing the VOCs from the PTFE and substantially reduced pesticide contamination from the LDPE.« less

Identification of targets at remote distances with Raman spectroscopy

NASA Astrophysics Data System (ADS)

Cox, Rick; Williams, Brad; Harpster, Mark H.

2012-06-01

In the past few years, there has arisen an intense demand for new generation technologies which provide for the rapid and sensitive stand-off detection of explosive compounds and hazardous chemicals. This has been fueled, in large part, by the escalation of threats to homeland security and the debilitating effects of IED devices in both civilian and war zones. In this paper, we describe two portable stand-off Raman spectrometers which have been developed by DeltaNu and are intended for use in different test environments. The first, the DeltaNu ObserveR™, is a handheld785 nm laser device suited for the close range detection of explosive materials during nighttime operations, or indoors under restricted light conditions. The second device, the ObserveR LR, is a tripod-mounted, solar blind system that enables detection at longer distances (ca. <30 m) with reduced fluorescence interference. A condensed summary is presented of different tests that have been conducted using these devices, and results are discussed within the context of technological improvements that will be required to adequately meet the challenge of robust explosive material detection.

Finite element simulation of structural performance on flexible pavements with stabilized base/treated subbase materials under accelerated loading.

DOT National Transportation Integrated Search

2011-12-01

Accelerated pavement testing (APT) has been increasingly used by state highway agencies in recent years for evaluating pavement structures and/or materials. However, running an APT experiment is expensive. It requires costly accelerated loading devic...

Standards for dielectric elastomer transducers

NASA Astrophysics Data System (ADS)

Carpi, Federico; Anderson, Iain; Bauer, Siegfried; Frediani, Gabriele; Gallone, Giuseppe; Gei, Massimiliano; Graaf, Christian; Jean-Mistral, Claire; Kaal, William; Kofod, Guggi; Kollosche, Matthias; Kornbluh, Roy; Lassen, Benny; Matysek, Marc; Michel, Silvain; Nowak, Stephan; O'Brien, Benjamin; Pei, Qibing; Pelrine, Ron; Rechenbach, Björn; Rosset, Samuel; Shea, Herbert

2015-10-01

Dielectric elastomer transducers consist of thin electrically insulating elastomeric membranes coated on both sides with compliant electrodes. They are a promising electromechanically active polymer technology that may be used for actuators, strain sensors, and electrical generators that harvest mechanical energy. The rapid development of this field calls for the first standards, collecting guidelines on how to assess and compare the performance of materials and devices. This paper addresses this need, presenting standardized methods for material characterisation, device testing and performance measurement. These proposed standards are intended to have a general scope and a broad applicability to different material types and device configurations. Nevertheless, they also intentionally exclude some aspects where knowledge and/or consensus in the literature were deemed to be insufficient. This is a sign of a young and vital field, whose research development is expected to benefit from this effort towards standardisation.

Solid-phase extraction microfluidic devices for matrix removal in trace element assay of actinide materials

DOE PAGES

Gao, Jun; Manard, Benjamin Thomas; Castro, Alonso; ...

2017-02-02

Advances in sample nebulization and injection technology have significantly reduced the volume of solution required for trace impurity analysis in plutonium and uranium materials. Correspondingly, we have designed and tested a novel chip-based microfluidic platform, containing a 100-µL or 20-µL solid-phase microextraction column, packed by centrifugation, which supports nuclear material mass and solution volume reductions of 90% or more compared to standard methods. Quantitative recovery of 28 trace elements in uranium was demonstrated using a UTEVA chromatographic resin column, and trace element recovery from thorium (a surrogate for plutonium) was similarly demonstrated using anion exchange resin AG MP-1. Of ninemore » materials tested, compatibility of polyvinyl chloride (PVC), polypropylene (PP), and polytetrafluoroethylene (PTFE) chips with the strong nitric acid media was highest. Finally, the microcolumns can be incorporated into a variety of devices and systems, and can be loaded with other solid-phase resins for trace element assay in high-purity metals.« less

Solid-phase extraction microfluidic devices for matrix removal in trace element assay of actinide materials

DOE Office of Scientific and Technical Information (OSTI.GOV)

Gao, Jun; Manard, Benjamin Thomas; Castro, Alonso

Advances in sample nebulization and injection technology have significantly reduced the volume of solution required for trace impurity analysis in plutonium and uranium materials. Correspondingly, we have designed and tested a novel chip-based microfluidic platform, containing a 100-µL or 20-µL solid-phase microextraction column, packed by centrifugation, which supports nuclear material mass and solution volume reductions of 90% or more compared to standard methods. Quantitative recovery of 28 trace elements in uranium was demonstrated using a UTEVA chromatographic resin column, and trace element recovery from thorium (a surrogate for plutonium) was similarly demonstrated using anion exchange resin AG MP-1. Of ninemore » materials tested, compatibility of polyvinyl chloride (PVC), polypropylene (PP), and polytetrafluoroethylene (PTFE) chips with the strong nitric acid media was highest. Finally, the microcolumns can be incorporated into a variety of devices and systems, and can be loaded with other solid-phase resins for trace element assay in high-purity metals.« less

49 CFR Appendix D to Part 178 - Thermal Resistance Test

Code of Federal Regulations, 2010 CFR

2010-10-01

... must be large enough in size to fully house the test outer package without clearance problems. The test....3Instrumentation. A calibrated recording device or a computerized data acquisition system with an appropriate range... Configuration. Each outer package material type and design must be tested, including any features such as...

Electromagnetic field tapering using all-dielectric gradient index materials.

PubMed

Yi, Jianjia; Piau, Gérard-Pascal; de Lustrac, André; Burokur, Shah Nawaz

2016-07-28

The concept of transformation optics (TO) is applied to control the flow of electromagnetic fields between two sections of different dimensions through a tapering device. The broadband performance of the field taper is numerically and experimentally validated. The taper device presents a graded permittivity profile and is fabricated through three-dimensional (3D) polyjet printing technology using low-cost all-dielectric materials. Calculated and measured near-field mappings are presented in order to validate the proposed taper. A good qualitative agreement is obtained between full-wave simulations and experimental tests. Such all-dielectric taper paves the way to novel types of microwave devices that can be easily fabricated through low-cost additive manufacturing processes.

Induction simulation of gas core nuclear engine

NASA Technical Reports Server (NTRS)

Poole, J. W.; Vogel, C. E.

1973-01-01

The design, construction and operation of an induction heated plasma device known as a combined principles simulator is discussed. This device incorporates the major design features of the gas core nuclear rocket engine such as solid feed, propellant seeding, propellant injection through the walls, and a transpiration cooled, choked flow nozzle. Both argon and nitrogen were used as propellant simulating material, and sodium was used for fuel simulating material. In addition, a number of experiments were conducted utilizing depleted uranium as the fuel. The test program revealed that satisfactory operation of this device can be accomplished over a range of operating conditions and provided additional data to confirm the validity of the gas core concept.

Advances in photonic MOEMS-MEMS device thinning and polishing

NASA Astrophysics Data System (ADS)

McAneny, James J.; Kennedy, Mark; McGroggan, Tom

2010-02-01

As devices continue to increase in density and complexity, ever more stringent specifications are placed on the wafer scale equipment manufacturers to produce higher quality and higher output. This results in greater investment and more resource being diverted into producing tools and processes which can meet the latest demanding criteria. Substrate materials employed in the fabrication process range from Silicon through InP and include GaAs, InSb and other optical networking or waveguide materials. With this diversity of substrate materials presented, controlling the geometries and surfaces grows progressively more challenging. This article highlights the key parameters which require close monitoring and control in order to produce highly precise wafers as part of the fabrication process. Several as cut and commercially available standard polished wafer materials were used in empirical trials to test tooling options in generating high levels of geometric control over the dimensions while producing high quality surface finishes. Specific attention was given to the measurement and control of: flatness; parallelism/TTV; surface roughness and final target thickness as common specifications required by the industry. By combining the process variables of: plate speed, download pressure, slurry flow rate and concentration, pad type and wafer travel path across the polish pad, the effect of altering these variables was recorded and analysed to realize the optimum process conditions for the materials under test. The results being then used to design improved methods and tooling for the thinning and polishing of photonic materials applied to MOEMS-MEMS device fabrication.

Experimental study of shear rate dependence in perpetually sheared granular matter

NASA Astrophysics Data System (ADS)

Liu, Sophie Yang; Guillard, François; Marks, Benjy; Rognon, Pierre; Einav, Itai

2017-06-01

We study the shear behaviour of various granular materials by conducting novel perpetual simple shear experiments over four orders of magnitude of relatively low shear rates. The newly developed experimental apparatus employed is called "3D Stadium Shear Device" which is an extended version of the 2D Stadium Shear Device [1]. This device is able to provide a non-radial dependent perpetual shear flow and a nearly linear velocity profile between two oppositely moving shear walls. Using this device, we are able to test a large variety of granular materials. Here, we demonstrate the applicability of the device on glass beads (diameter 1 mm, 3 mm, and 14 mm) and rice. We particularly focus on studying these materials at very low inertial number I ranging from 10-6 to 10-2. We find that, within this range of I, the friction coefficient μ of glass beads has no shear rate dependence. A particularly appealing observation comes from testing rice, where the attainment of critical state develops under much longer duration than in other materials. Initially during shear we find a value of μ similar to that found for glass beads, but with time this value decreases gradually towards the asymptotic critical state value. The reason, we believe, lies in the fact that rice grains are strongly elongated; hence the time to achieve the stable μ is primarily controlled by the time for particles to align themselves with respect to the shear walls. Furthermore, the initial packing conditions of samples also plays a role in the evolution of μ when the shear strain is small, but that impact will eventually be erased after sufficient shear strain.

Flowability of granular materials with industrial applications - An experimental approach

NASA Astrophysics Data System (ADS)

Torres-Serra, Joel; Romero, Enrique; Rodríguez-Ferran, Antonio; Caba, Joan; Arderiu, Xavier; Padullés, Josep-Manel; González, Juanjo

2017-06-01

Designing bulk material handling equipment requires a thorough understanding of the mechanical behaviour of powders and grains. Experimental characterization of granular materials is introduced focusing on flowability. A new prototype is presented which performs granular column collapse tests. The device consists of a channel whose design accounts for test inspection using visualization techniques and load measurements. A reservoir is attached where packing state of the granular material can be adjusted before run-off to simulate actual handling conditions by fluidisation and deaeration of the pile. Bulk materials on the market, with a wide range of particle sizes, can be tested with the prototype and the results used for classification in terms of flowability to improve industrial equipment selection processes.

Development of a new magnetocaloric material used in a magnetic refrigeration device

NASA Astrophysics Data System (ADS)

Guillou, F.; Legait, U.; Kedous-Lebouc, A.; Hardy, V.

2012-06-01

Testing directly a magnetocaloric material in a magnetic refrigeration (MR) system is the best way to judge of its applicative potentialities. In this spirit, an oxide expected to show promising magnetocaloric properties around room temperature (Pr0.65Sr0.35MnO3) was produced in large scale and shaped in order to build a regenerator. Magnetization, heat capacity, resistivity, thermal conductivity and a direct test in a MR device were carried out on this manganite. The results were compared to those observed in the reference material which is Gadolinium. The two main conclusions of these preliminary results are: (i) the Pr0.65Sr0.35MnO3 actually displays not only a significant magnetocaloric effect but also a real refrigeration capability at room temperature; (ii) the temperature spans reached in these first experiments are even found to well compare with those obtained with Gd.

High Curie temperature drive layer materials for ion-implanted magnetic bubble devices

NASA Technical Reports Server (NTRS)

Fratello, V. J.; Wolfe, R.; Blank, S. L.; Nelson, T. J.

1984-01-01

Ion implantation of bubble garnets can lower the Curie temperature by 70 C or more, thus limiting high temperature operation of devices with ion-implanted propagation patterns. Therefore, double-layer materials were made with a conventional 2-micron bubble storage layer capped by an ion-implantable drive layer of high Curie temperature, high magnetostriction material. Contiguous disk test patterns were implanted with varying doses of a typical triple implant. Quality of propagation was judged by quasistatic tests on 8-micron period major and minor loops. Variations of magnetization, uniaxial anisotropy, implant dose, and magnetostriction were investigated to ensure optimum flux matching, good charged wall coupling, and wide operating margins. The most successful drive layer compositions were in the systems (SmDyLuCa)3(FeSi)5O12 and (BiGdTmCa)3(FeSi)5O12 and had Curie temperatures 25-44 C higher than the storage layers.

Laser-based irradiation apparatus and methods for monitoring the dose-rate response of semiconductor devices

DOEpatents

Horn, Kevin M [Albuquerque, NM

2006-03-28

A scanned, pulsed, focused laser irradiation apparatus can measure and image the photocurrent collection resulting from a dose-rate equivalent exposure to infrared laser light across an entire silicon die. Comparisons of dose-rate response images or time-delay images from before, during, and after accelerated aging of a device, or from periodic sampling of devices from fielded operational systems allows precise identification of those specific age-affected circuit structures within a device that merit further quantitative analysis with targeted materials or electrical testing techniques. Another embodiment of the invention comprises a broad-beam, dose rate-equivalent exposure apparatus. The broad-beam laser irradiation apparatus can determine if aging has affected the device's overall functionality. This embodiment can be combined with the synchronized introduction of external electrical transients into a device under test to simulate the electrical effects of the surrounding circuitry's response to a radiation exposure.

Physics-based process modeling, reliability prediction, and design guidelines for flip-chip devices

NASA Astrophysics Data System (ADS)

Michaelides, Stylianos

Flip Chip on Board (FCOB) and Chip-Scale Packages (CSPs) are relatively new technologies that are being increasingly used in the electronic packaging industry. Compared to the more widely used face-up wirebonding and TAB technologies, flip-chips and most CSPs provide the shortest possible leads, lower inductance, higher frequency, better noise control, higher density, greater input/output (I/O), smaller device footprint and lower profile. However, due to the short history and due to the introduction of several new electronic materials, designs, and processing conditions, very limited work has been done to understand the role of material, geometry, and processing parameters on the reliability of flip-chip devices. Also, with the ever-increasing complexity of semiconductor packages and with the continued reduction in time to market, it is too costly to wait until the later stages of design and testing to discover that the reliability is not satisfactory. The objective of the research is to develop integrated process-reliability models that will take into consideration the mechanics of assembly processes to be able to determine the reliability of face-down devices under thermal cycling and long-term temperature dwelling. The models incorporate the time and temperature-dependent constitutive behavior of various materials in the assembly to be able to predict failure modes such as die cracking and solder cracking. In addition, the models account for process-induced defects and macro-micro features of the assembly. Creep-fatigue and continuum-damage mechanics models for the solder interconnects and fracture-mechanics models for the die have been used to determine the reliability of the devices. The results predicted by the models have been successfully validated against experimental data. The validated models have been used to develop qualification and test procedures for implantable medical devices. In addition, the research has helped develop innovative face-down devices without the underfill, based on the thorough understanding of the failure modes. Also, practical design guidelines for material, geometry and process parameters for reliable flip-chip devices have been developed.

GaN-on-diamond electronic device reliability: Mechanical and thermo-mechanical integrity

NASA Astrophysics Data System (ADS)

Liu, Dong; Sun, Huarui; Pomeroy, James W.; Francis, Daniel; Faili, Firooz; Twitchen, Daniel J.; Kuball, Martin

2015-12-01

The mechanical and thermo-mechanical integrity of GaN-on-diamond wafers used for ultra-high power microwave electronic devices was studied using a micro-pillar based in situ mechanical testing approach combined with an optical investigation of the stress and heat transfer across interfaces. We find the GaN/diamond interface to be thermo-mechanically stable, illustrating the potential for this material for reliable GaN electronic devices.

Proof of concept testing of a positive reference material for in vivo and in vitro skin irritation testing.

PubMed

Nomura, Yusuke; Lee, Michelle; Fukui, Chie; Watanabe, Kayo; Olsen, Daniel; Turley, Audrey; Morishita, Yuki; Kawakami, Tsuyoshi; Yuba, Toshiyasu; Fujimaki, Hideo; Inoue, Kaoru; Yoshida, Midori; Ogawa, Kumiko; Haishima, Yuji

2017-12-11

In vivo and in vitro irritation testing is important for evaluating the biological safety of medical devices. Here, the performance of positive reference materials for skin irritation testing was evaluated. Four reference standards, referred to as Y-series materials, were analyzed: a polyvinyl chloride (PVC) sheet spiked with 0 (Y-1), 1.0 (Y-2), 1.5 (Y-3), or 10 (Y-4) parts of Genapol X-080 per 100 parts of PVC by weight. Y-1, Y-2, and Y-3 did not induce skin irritation responses in an in vitro reconstructed human epidermis (RhE) tissue model, as measured by tissue viability or interleukin-1α release, or in an in vivo intracutaneous response test using rabbits. In contrast, Y-4 extracts prepared with saline or sesame oil at 37°C and 50°C clearly elicited positive irritation responses, including reduced viability (< 50%) and significantly higher interleukin-1α release compared with the solvent alone group, in the RhE tissue model and an intracutaneous response test, where substantial necrosis was observed by histopathology. The positive skin irritation responses induced in vitro under various extraction conditions, as well as those elicited in vivo, indicate that Y-4 is an effective extractable positive control material for in vivo and in vitro skin irritation tests of medical devices. © 2017 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 2017. © 2017 Wiley Periodicals, Inc.

Vacuum stability testing of Apollo 15 Scientific Instrument Module (SIM) non-metallic materials and reversion of silicone rubber in a motor switch

NASA Technical Reports Server (NTRS)

Clancy, H. M.

1972-01-01

Vacuum stability screening tests were performed on the Apollo 15 Scientific Instrument Module (SIM) bay nonmetallic materials in accordance with the NASA document SP-R-0022. The testing was necessary to support the evaluation to determine the effect material outgassing contamination would have on the SIM bay optical lenses and sensing devices. The Apollo 15 SIM experiments were highly successful, therefore, it is assumed that contamination due to the outgassing of nonmetallic materials did not affect equipment operation. A related problem, the reversion of a silicone rubber grommet which affected an electrical motor switch operation is also reported.

Use of loading-unloading compression curves in medical device design

NASA Astrophysics Data System (ADS)

Ciornei, M. C.; Alaci, S.; Ciornei, F. C.; Romanu, I. C.

2017-08-01

The paper presents a method and experimental results regarding mechanical testing of soft materials. In order to characterize the mechanical behaviour of technological materials used in prosthesis, a large number of material constants are required, as well as the comparison to the original. The present paper proposes as methodology the comparison between compression loading-unloading curves corresponding to a soft biological tissue and to a synthetic material. To this purpose, a device was designed based on the principle of the dynamic harness test. A moving load is considered and the force upon the indenter is controlled for loading-unloading phases. The load and specimen deformation are simultaneously recorded. A significant contribution of this paper is the interpolation of experimental data by power law functions, a difficult task because of the instability of the system of equations to be optimized. Finding the interpolation function was simplified, from solving a system of transcendental equations to solving a unique equation. The characteristic parameters of the experimentally curves must be compared to the ones corresponding to actual tissue. The tests were performed for two cases: first, using a spherical punch, and second, for a flat-ended cylindrical punch.

Scientific Ground of a New Optical Device for Contactless Measurement of the Small Spatial Displacements of Control Object Surfaces

NASA Astrophysics Data System (ADS)

Miroshnichenko, I. P.; Parinov, I. A.

2017-06-01

It is proposed the computational-experimental ground of newly developed optical device for contactless measurement of small spatial displacements of control object surfaces based on the use of new methods of laser interferometry. The proposed device allows one to register linear and angular components of the small displacements of control object surfaces during the diagnosis of the condition of structural materials for forced elements of goods under exploring by using acoustic non-destructive testing methods. The described results are the most suitable for application in the process of high-precision measurements of small linear and angular displacements of control object surfaces during experimental research, the evaluation and diagnosis of the state of construction materials for forced elements of goods, the study of fast wave propagation in layered constructions of complex shape, manufactured of anisotropic composite materials, the study of damage processes in modern construction materials in mechanical engineering, shipbuilding, aviation, instrumentation, power engineering, etc.

Cadmium telluride leaching behavior: Discussion of Zeng et al. (2015).

PubMed

Sinha, Parikhit

2015-11-01

Zeng et al. (2015) evaluate the leaching behavior and surface chemistry of II-VI semiconductor materials, CdTe and CdSe, in response to pH and O2. Under agitation in acidic and aerobic conditions, the authors found approximately 3.6%-6.4% (w/w) solubility of Cd content in CdTe in the Toxicity Characteristic Leaching Procedure (TCLP), Waste Extraction Test (WET), and dissolution test, with lower solubility (0.56-0.58%) under agitation in acidic and anoxic conditions. This range is comparable with prior long-term transformation and dissolution testing and bio-elution testing of CdTe (2.3%-4.1% w/w solubility of Cd content in CdTe). The implications for potential leaching behavior of CdTe-containing devices require further data. Since CdTe PV modules contain approximately 0.05% Cd content by mass, the starting Cd content in the evaluation of CdTe-containing devices would be lower by three orders of magnitude than the starting Cd content in the authors' study, and leaching potential would be further limited by the monolithic glass-adhesive laminate-glass structure of the device that encapsulates the semiconductor material. Experimental evaluation of leaching potential of CdTe PV modules crushed by landfill compactor has been conducted, with results of TCLP and WET tests on the crushed material below regulatory limits for Cd. CdTe PV recycling technology has been in commercial operation since 2005 with high yields for semiconductor (95%) and glass (90%) recovery. Copyright © 2015 Elsevier Ltd. All rights reserved.

Contribution a la caracterisation des betons endommages par des methodes de l'acoustique non lineaire. Application a la reaction alcalis-silice

NASA Astrophysics Data System (ADS)

Kodjo, Apedovi

The aim of this thesis is to contribute to the non-destructive characterization of concrete materials damaged by alkali-silica reaction (ASR). For this purpose, some nonlinear characterization techniques have been developed, as well as a nonlinear resonance test device. In order to optimize the sensitivity of the test device, the excitation module and signal processing have been improved. The nonlinear tests were conducted on seven samples of concrete damaged by ASR, three samples of concrete damaged by heat, three concrete samples damaged mechanically and three sound concrete samples. Since, nonlinear behaviour of the material is often attribute to its micro-defects hysteretic behaviour, it was shown at first that concrete damaged by ASR exhibits an hysteresis behaviour. To conduct this study, an acoustoelastic test was set, and then nonlinear resonance test device was used for characterizing sound concrete and concrete damaged by ASR. It was shown that the nonlinear technique can be used for characterizing the material without knowing its initial state, and also for detecting early damage in the reactive material. Studies were also carried out on the effect of moisture regarding the nonlinear parameters; they allowed understanding the low values of nonlinear parameters measured on concrete samples that were kept in high moisture conditions. In order to find a specific characteristic of damage caused by ASR, the viscosity of ASR gel was used. An approach, based on static creep analysis, performed on the material, while applying the nonlinear resonance technique. The spring-damping model of Maxwell was used for the interpretation of the results. Then, the creep time was analysed on samples damaged by ASR. It appears that the ASR gel increases the creep time. Finally, the limitations of the nonlinear resonance technique for in situ application have been explained and a new applicable nonlinear technique was initiated. This technique use an external source such as a mass for making non-linearity behaviour in the material, while an ultrasound wave is investigating the medium. Keywords. Concrete, Alkali-silica reaction, Nonlinear acoustics, Nonlinearity, Hysteresis, Damage diagnostics.

Examination of a Wear-Reducing Muzzle Device

DTIC Science & Technology

2013-08-01

resistant material attached to the muzzle end of the gun tube. The bore diameter of the device is slightly less than the bore diameter of the gun. The...3  Figure 3. Weapon and universal bearing slide used for firings ...small caliber round of ammunition. ..........21  v List of Tables Table 1. Firing test matrix for phase 1

In-flight friction and wear mechanism

NASA Technical Reports Server (NTRS)

Devine, E. J.; Evans, H. E.

1975-01-01

A unique mechanism developed for conducting friction and wear experiments in orbit is described. The device is capable of testing twelve material samples simultaneously. Parameters considered critical include: power, weight, volume, mounting, cleanliness, and thermal designs. The device performed flawlessly in orbit over an eighteen month period and demonstrated the usefulness of this design for future unmanned spacecraft or shuttle applications.

A field-emission based vacuum device for the generation of THz waves

NASA Astrophysics Data System (ADS)

Lin, Ming-Chieh

2005-03-01

Terahertz waves have been used to characterize the electronic, vibrational and compositional properties of solid, liquid and gas phase materials during the past decade. More and more applications in imaging science and technology call for the well development of THz wave sources. Amplification and generation of a high frequency electromagnetic wave are a common interest of field emission based devices. In the present work, we propose a vacuum electronic device based on field emission mechanism for the generation of THz waves. To verify our thinking and designs, the cold tests and the hot tests have been studied via the simulation tools, SUPERFISH and MAGIC. In the hot tests, two types of electron emission mechanisms are considered. One is the field emission and the other is the explosive emission. The preliminary design of the device is carried out and tested by the numerical simulations. The simulation results show that an electronic efficiency up to 4% can be achieved without employing any magnetic circuits.

Critical shear stress measurement of cohesive soils in streams: identifying device-dependent variability using an in-situ jet test device and conduit flume

NASA Astrophysics Data System (ADS)

Mahalder, B.; Schwartz, J. S.; Palomino, A.; Papanicolaou, T.

2016-12-01

Cohesive soil erodibility and threshold shear stress for stream bed and bank are dependent on both soil physical and geochemical properties in association with the channel vegetative conditions. These properties can be spatially variable therefore making critical shear stress measurement in cohesive soil challenging and leads to a need for a more comprehensive understanding of the erosional processes in streams. Several in-situ and flume-type test devices for estimating critical shear stress have been introduced by different researchers; however reported shear stress estimates per device vary widely in orders of magnitude. Advantages and disadvantages exist between these devices. Development of in-situ test devices leave the bed and/or bank material relatively undisturbed and can capture the variable nature of field soil conditions. However, laboratory flumes provide a means to control environmental conditions that can be quantify and tested. This study was conducted to observe differences in critical shear stress using jet tester and a well-controlled conduit flume. Soil samples were collected from the jet test locations and tested in a pressurized flume following standard operational procedure to calculate the critical shear stress. The results were compared using statistical data analysis (mean-separation ANOVA procedure) to identify possible differences. In addition to the device comparison, the mini jet device was used to measure critical shear stress across geologically diverse regions of Tennessee, USA. Statistical correlation between critical shear stress and the soil physical, and geochemical properties were completed identifying that geological origin plays a significant role in critical shear stress prediction for cohesive soils. Finally, the critical shear stress prediction equations using the jet test data were examined with possible suggestions to modify based on the flume test results.

Bilaminar Device of Poly(Lactic-co-Glycolic Acid)/Collagen Cultured With Adipose-Derived Stem Cells for Dermal Regeneration.

PubMed

Domingues, Juliana A; Cherutti, Giselle; Motta, Adriana C; Hausen, Moema A; Oliveira, Rômulo T D; Silva-Zacarin, Elaine C M; Barbo, Maria Lourdes P; Duek, Eliana A R

2016-10-01

Several materials are commercially available as substitutes for skin. However, new strategies are needed to improve the treatment of skin wounds. In this study, we developed and characterized a new device consisting of poly(lactic-co-glycolic acid) (PLGA) and collagen associated with mesenchymal stem cells derived from human adipose tissue. To develop the bilaminar device, we initially obtained a membrane of PLGA by dissolving the copolymer in chloroform and then produced a collagen type I scaffold by freeze-drying. The materials were characterized physically by gel permeation chromatography, scanning electron microscopy, and mass loss. Biological activity was assessed by cell proliferation assay. A preliminary study in vivo was performed with a pig model in which tissue regeneration was assessed macroscopically and histologically, the commercial device Integra being used as a control. The PLGA/collagen bilaminar material was porous, hydrolytically degradable, and compatible with skin growth. The polymer complex allowed cell adhesion and proliferation, making it a potentially useful cell carrier. In addition, the transparency of the material allowed monitoring of the lesion when the dressings were changed. Xenogeneic mesenchymal cells cultured on the device (PLGA/collagen/ASC) showed a reduced granulomatous reaction to bovine collagen, down-regulation of α-SMA, enhancement in the number of neoformed blood vessels, and collagen organization as compared with normal skin; the device was superior to other materials tested (PLGA/collagen and Integra) in its ability to stimulate the formation of new cutaneous tissue. Copyright © 2016 International Center for Artificial Organs and Transplantation and Wiley Periodicals, Inc.

Stretchable carbon nanotube charge-trap floating-gate memory and logic devices for wearable electronics.

PubMed

Son, Donghee; Koo, Ja Hoon; Song, Jun-Kyul; Kim, Jaemin; Lee, Mincheol; Shim, Hyung Joon; Park, Minjoon; Lee, Minbaek; Kim, Ji Hoon; Kim, Dae-Hyeong

2015-05-26

Electronics for wearable applications require soft, flexible, and stretchable materials and designs to overcome the mechanical mismatch between the human body and devices. A key requirement for such wearable electronics is reliable operation with high performance and robustness during various deformations induced by motions. Here, we present materials and device design strategies for the core elements of wearable electronics, such as transistors, charge-trap floating-gate memory units, and various logic gates, with stretchable form factors. The use of semiconducting carbon nanotube networks designed for integration with charge traps and ultrathin dielectric layers meets the performance requirements as well as reliability, proven by detailed material and electrical characterizations using statistics. Serpentine interconnections and neutral mechanical plane layouts further enhance the deformability required for skin-based systems. Repetitive stretching tests and studies in mechanics corroborate the validity of the current approaches.

Guided bone augmentation using ceramic space-maintaining devices: the impact of chemistry

PubMed Central

Anderud, Jonas; Abrahamsson, Peter; Jimbo, Ryo; Isaksson, Sten; Adolfsson, Erik; Malmström, Johan; Naito, Yoshihito; Wennerberg, Ann

2015-01-01

The purpose of the study was to evaluate histologically, whether vertical bone augmentation can be achieved using a hollow ceramic space maintaining device in a rabbit calvaria model. Furthermore, the chemistry of microporous hydroxyapatite and zirconia were tested to determine which of these two ceramics are most suitable for guided bone generation. 24 hollow domes in two different ceramic materials were placed subperiosteal on rabbit skull bone. The rabbits were sacrificed after 12 weeks and the histology results were analyzed regarding bone-to-material contact and volume of newly formed bone. The results suggest that the effect of the microporous structure of hydroxyapatite seems to facilitate for the bone cells to adhere to the material and that zirconia enhance a slightly larger volume of newly formed bone. In conclusion, the results of the current study demonstrated that ceramic space maintaining devices permits new bone formation and osteoconduction within the dome. PMID:25792855

Fabrication of a bioadhesive transdermal device from chitosan and hyaluronic acid for the controlled release of lidocaine.

PubMed

Anirudhan, T S; Nair, Syam S; Nair, Anoop S

2016-11-05

A novel efficient transdermal (TD) lidocaine (LD) delivery device based on chitosan (CS) and hyaluronic acid (HA) was successfully developed in the present investigation. CS was grafted with glycidyl methacrylate (GMA) and butyl methacrylate (BMA) to fabricate a versatile material with improved adhesion and mechanical properties. HA was hydrophobically modified by covalently conjugating 3-(dimethylamino)-1-propylamine (DMPA) to encapsulate poorly water soluble LD and was uniformly dispersed in modified CS matrix. The prepared materials were characterized through FTIR, NMR, XRD, SEM, TEM and tensile assay. The dispersion of amine functionalized HA (AHA) on modified CS matrix offered strong matrix - filler interaction, which improved the mechanical properties and drug retention behavior of the device. In vitro skin permeation study of LD was performed with modified Franz diffusion cell using rat skin and exhibited controlled release. The influence of storage time on release profile was investigated and demonstrated that after the initial burst, LD release profile of the device after 30 and 60days storage was identical to that of a device which was not stored. In vivo skin adhesion test and skin irritation assay in human subjects, water vapor permeability and environmental fitness test was performed to judge its application in biomedical field. All results displayed that the fabricated device is a potential candidate for TD LD administration to the systemic circulation. Copyright © 2016 Elsevier Ltd. All rights reserved.

Collecting Ground Samples for Balloon-Borne Instruments

NASA Technical Reports Server (NTRS)

Jones, Jack; Zimmerman, Wayne; Wu, Jiunn Jenq

2009-01-01

A proposed system in a gondola containing scientific instruments suspended by a balloon over the surface of the Saturn moon Titan would quickly acquire samples of rock or ice from the ground below. Prototypes of a sample-collecting device that would be a major part of the system have been tested under cryogenic and non-cryogenic conditions on Earth. Systems like this one could also be used in non-cryogenic environments on Earth to collect samples of rock, soil, ice, mud, or other ground material from such inaccessible or hazardous locations as sites of suspected chemical spills or biological contamination. The sample-collecting device would be a harpoonlike device that would be connected to the balloon-borne gondola by a tether long enough to reach the ground. The device would be dropped from the gondola to acquire a sample, then would be reeled back up to the gondola, where the sample would be analyzed by the onboard instruments. Each prototype of the sample-collecting device has a sharp front (lower) end, a hollow core for retaining a sample, a spring for holding the sample in the hollow core, and a rear (upper) annular cavity for retaining liquid sample material. Aerodynamic fins at the rear help to keep the front end pointed downward. In tests, these prototype devices were dropped from various heights and used to gather samples of dry sand, moist sand, cryogenic water ice, and warmer water ice.

Superconductivity devices: Commercial use of space

NASA Technical Reports Server (NTRS)

Haertling, Gene; Furman, Eugene; Hsi, Chi-Shiung; Li, Guang

1993-01-01

The processing and screen printing of the superconducting BSCCO and 123 YBCO materials on substrates is described. The resulting superconducting properties and the use of these materials as possible electrode materials for ferroelectrics at 77 K are evaluated. Also, work performed in the development of solid-state electromechanical actuators is reported. Specific details include the fabrication and processing of high strain PBZT and PLZT electrostrictive materials, the development of PSZT and PMN-based ceramics, and the testing and evaluation of these electrostrictive materials. Finally, the results of studies on a new processing technology for preparing piezoelectric and electrostrictive ceramic materials are summarized. The process involves a high temperature chemical reduction which leads to an internal pre-stressing of the oxide wafer. These reduced and internally biased oxide wafers (RAINBOW) can produce bending-mode actuator devices which possess a factor of ten more displacement and load bearing capacity than present-day benders.

49 CFR Appendix A to Part 223 - Certification of Glazing Materials

Code of Federal Regulations, 2010 CFR

2010-10-01

...-ups, test measuring devices, and test procedures were performed by qualified personnel using... following tests: (i) Ballistic Impact in which a standard 22 caliber long rifle lead bullet of 40 grains in... Impact in which a standard 22 caliber long rifle lead bullet of 40 grains in weight impacts at a minimum...

Modeling, design, packing and experimental analysis of liquid-phase shear-horizontal surface acoustic wave sensors

NASA Astrophysics Data System (ADS)

Pollard, Thomas B

Recent advances in microbiology, computational capabilities, and microelectromechanical-system fabrication techniques permit modeling, design, and fabrication of low-cost, miniature, sensitive and selective liquid-phase sensors and lab-on-a-chip systems. Such devices are expected to replace expensive, time-consuming, and bulky laboratory-based testing equipment. Potential applications for devices include: fluid characterization for material science and industry; chemical analysis in medicine and pharmacology; study of biological processes; food analysis; chemical kinetics analysis; and environmental monitoring. When combined with liquid-phase packaging, sensors based on surface-acoustic-wave (SAW) technology are considered strong candidates. For this reason such devices are focused on in this work; emphasis placed on device modeling and packaging for liquid-phase operation. Regarding modeling, topics considered include mode excitation efficiency of transducers; mode sensitivity based on guiding structure materials/geometries; and use of new piezoelectric materials. On packaging, topics considered include package interfacing with SAW devices, and minimization of packaging effects on device performance. In this work novel numerical models are theoretically developed and implemented to study propagation and transduction characteristics of sensor designs using wave/constitutive equations, Green's functions, and boundary/finite element methods. Using developed simulation tools that consider finite-thickness of all device electrodes, transduction efficiency for SAW transducers with neighboring uniform or periodic guiding electrodes is reported for the first time. Results indicate finite electrode thickness strongly affects efficiency. Using dense electrodes, efficiency is shown to approach 92% and 100% for uniform and periodic electrode guiding, respectively; yielding improved sensor detection limits. A numerical sensitivity analysis is presented targeting viscosity using uniform-electrode and shear-horizontal mode configurations on potassium-niobate, langasite, and quartz substrates. Optimum configurations are determined yielding maximum sensitivity. Results show mode propagation-loss and sensitivity to viscosity are correlated by a factor independent of substrate material. The analysis is useful for designing devices meeting sensitivity and signal level requirements. A novel, rapid and precise microfluidic chamber alignment/bonding method was developed for SAW platforms. The package is shown to have little effect on device performance and permits simple macrofluidic interfacing. Lastly, prototypes were designed, fabricated, and tested for viscosity and biosensor applications; results show ability to detect as low as 1% glycerol in water and surface-bound DNA crosslinking.

Air Pollution Tests Using the "DEMA"

ERIC Educational Resources Information Center

Wilt, L. M.

1970-01-01

Describes the making and calibrating of a DEMA (DEvice for Measuring Air) from readily available, inexpensive materials. Procedures for measuring atmospheric particulates, acids, and carbon monoxide are described. (PR)

Combustion Device Failures During Space Shuttle Main Engine Development

NASA Technical Reports Server (NTRS)

Goetz, Otto K.; Monk, Jan C.

2005-01-01

Major Causes: Limited Initial Materials Properties. Limited Structural Models - especially fatigue. Limited Thermal Models. Limited Aerodynamic Models. Human Errors. Limited Component Test. High Pressure. Complicated Control.

Capacitance probe for detection of anomalies in non-metallic plastic pipe

DOEpatents

Mathur, Mahendra P.; Spenik, James L.; Condon, Christopher M.; Anderson, Rodney; Driscoll, Daniel J.; Fincham, Jr., William L.; Monazam, Esmail R.

2010-11-23

The disclosure relates to analysis of materials using a capacitive sensor to detect anomalies through comparison of measured capacitances. The capacitive sensor is used in conjunction with a capacitance measurement device, a location device, and a processor in order to generate a capacitance versus location output which may be inspected for the detection and localization of anomalies within the material under test. The components may be carried as payload on an inspection vehicle which may traverse through a pipe interior, allowing evaluation of nonmetallic or plastic pipes when the piping exterior is not accessible. In an embodiment, supporting components are solid-state devices powered by a low voltage on-board power supply, providing for use in environments where voltage levels may be restricted.

Towards High-Throughput, Simultaneous Characterization of Thermal and Thermoelectric Properties

NASA Astrophysics Data System (ADS)

Miers, Collier Stephen

The extension of thermoelectric generators to more general markets requires that the devices be affordable and practical (low $/Watt) to implement. A key challenge in this pursuit is the quick and accurate characterization of thermoelectric materials, which will allow researchers to tune and modify the material properties quickly. The goal of this thesis is to design and fabricate a high-throughput characterization system for the simultaneous characterization of thermal, electrical, and thermoelectric properties for device scale material samples. The measurement methodology presented in this thesis combines a custom designed measurement system created specifically for high-throughput testing with a novel device structure that permits simultaneous characterization of the material properties. The measurement system is based upon the 3o method for thermal conductivity measurements, with the addition of electrodes and voltage probes to measure the electrical conductivity and Seebeck coefficient. A device designed and optimized to permit the rapid characterization of thermoelectric materials is also presented. This structure is optimized to ensure 1D heat transfer within the sample, thus permitting rapid data analysis and fitting using a MATLAB script. Verification of the thermal portion of the system is presented using fused silica and sapphire materials for benchmarking. The fused silica samples yielded a thermal conductivity of 1.21 W/(m K), while a thermal conductivity of 31.2 W/(m K) was measured for the sapphire samples. The device and measurement system designed and developed in this thesis provide insight and serve as a foundation for the development of high throughput, simultaneous measurement platforms.

Electrical Arc Ignition Testing for Constellation Program

NASA Technical Reports Server (NTRS)

Sparks, Kyle; Gallus, Timothy; Smith, Sarah

2009-01-01

NASA Johnson Space Center (JSC) Materials and Processes Branch requested that NASA JSC White Sands Test Facility (WSTF) perform testing for the Constellation Program to evaluate the hazard of electrical arc ignition of materials that could be in close proximity to batteries. Specifically, WSTF was requested to perform wire-break electrical arc tests to determine the current threshold for ignition of generic cotton woven fabric samples with a fixed voltage of 3.7 V, a common voltage for hand-held electrical devices. The wire-break test was developed during a previous test program to evaluate the hazard of electrical arc ignition inside the Extravehicular Mobility Unit [1].

Design and development of data acquisition system for the Louisiana accelerated loading device : final report.

DOT National Transportation Integrated Search

1992-09-01

The Louisiana Transportation Research Center has established a Pavement Research Facility (PRF). The core of the PRF is a testing machine that is capable of conducting full-scale simulated and accelerated load testing of pavement materials, construct...

49 CFR 572.141 - General description.

Code of Federal Regulations, 2010 CFR

2010-10-01

... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST DEVICES 3-year-Old Child Crash Test Dummy, Alpha Version § 572.141 General description. (a) The Hybrid III 3-year-old child dummy is described by the following materials: (1) Technical drawings and specifications package 210-0000 (refer to...

In vitro dentin barrier cytotoxicity testing of some dental restorative materials.

PubMed

Jiang, R D; Lin, H; Zheng, G; Zhang, X M; Du, Q; Yang, M

2017-03-01

To investigate the cytotoxicity of four dental restorative materials in three-dimensional (3D) L929 cell cultures using a dentin barrier test. The cytotoxicities of light-cured glass ionomer cement (Vitrebond), total-etching adhesive (GLUMA Bond5), and two self-etching adhesives (GLUMA Self Etch and Single Bond Universal) were evaluated. The permeabilities of human dentin disks with thicknesses of 300, 500, and 1000μm were standardized using a hydraulic device. Test materials and controls were applied to the occlusal side of human dentin disks. The 3D-cell scaffolds were placed beneath the dentin disks. After a 24-h contact with the dentin barrier test device, cell viabilities were measured by performing MTT assays. Statistical analysis was performed using the Mann-Whitney U test. The mean (SD) permeabilities of the 300-μm, 500-μm, and 1000-μm dentin disks were 0.626 (0.214), 0.219 (0.0387) and 0.089 (0.028) μlmin -1 cm -2 cm H 2 O -1 . Vitrebond was severely cytotoxic, reducing the cell viability to 10% (300-μm disk), 17% (500μm), and 18% (1000μm). GLUMA Bond5 reduced the cell viability to 40% (300μm), 83% (500μm), and 86% (1000μm), showing moderate cytotoxicity (300-μm) and non-cytotoxicity (500-μm and 1000-μm). Single Bond Universal and GLUMA Self Etch did not significantly reduce cell viability, regardless of the dentin thicknesses, which characterized them as non-cytotoxic. Cytotoxicity varied with the materials tested and the thicknesses of the dentin disks. The tested cytotoxicity of materials applied on 300-, 500-, and 1000-μm dentin disks indicates that the clinical use of the test materials (excepting self-etching adhesives) in deep cavities poses a potential risk of damage to the pulp tissues to an extent, depending on the thickness of the remaining dentin. Copyright © 2017 Elsevier Ltd. All rights reserved.

An overview of thin film nitinol endovascular devices.

PubMed

Shayan, Mahdis; Chun, Youngjae

2015-07-01

Thin film nitinol has unique mechanical properties (e.g., superelasticity), excellent biocompatibility, and ultra-smooth surface, as well as shape memory behavior. All these features along with its low-profile physical dimension (i.e., a few micrometers thick) make this material an ideal candidate in developing low-profile medical devices (e.g., endovascular devices). Thin film nitinol-based devices can be collapsed and inserted in remarkably smaller diameter catheters for a wide range of catheter-based procedures; therefore, it can be easily delivered through highly tortuous or narrow vascular system. A high-quality thin film nitinol can be fabricated by vacuum sputter deposition technique. Micromachining techniques were used to create micro patterns on the thin film nitinol to provide fenestrations for nutrition and oxygen transport and to increase the device's flexibility for the devices used as thin film nitinol covered stent. In addition, a new surface treatment method has been developed for improving the hemocompatibility of thin film nitinol when it is used as a graft material in endovascular devices. Both in vitro and in vivo test data demonstrated a superior hemocompatibility of the thin film nitinol when compared with commercially available endovascular graft materials such as ePTFE or Dacron polyester. Promising features like these have motivated the development of thin film nitinol as a novel biomaterial for creating endovascular devices such as stent grafts, neurovascular flow diverters, and heart valves. This review focuses on thin film nitinol fabrication processes, mechanical and biological properties of the material, as well as current and potential thin film nitinol medical applications. Copyright © 2015 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

Evaluation of an Automated Reader and Color Interpretation-Based Immunoassays for Multiplexed Drug-of-Abuse Testing in Urine.

PubMed

Kim, Seon Young; Kim, Hyunjin; Park, Yeongchun; Lim, Jinsook; Kim, Jimyung; Koo, Sun Hoe; Kwon, Gye Cheol

2017-06-01

On-site drugs of abuse testing devices have undergone continuous improvement. We evaluated three devices with different designs: an automated reader, the Multi-Drug Screen Test Device with DxLINK (DxLINK; Innovacon, Alere, San Diego, USA) and two colorimetric immunoassays, the One Step Multi-Line Screen Panel with Integrated E-Z Split Key Cup II (E-Z Cup; Innovacon, Alere) and the One Step Multi-Drug Screen Panel card (Multi4 card; Alere, Abon Biopharm, Hangzhou, China). Eleven drugs [amphetamine, secobarbital, oxazepam, buprenorphine, benzoylecgonine, methylenedioxymethamphetamine (MDMA), 11-nor-9-carboxy-Δ9-tetrahydrocannabinol (THC), methamphetamine, methadone, morphine and nortriptyline] were tested using the DxLINK and E-Z Cup. Four drugs (benzoylecgonine, THC, methamphetamine and morphine) were tested using the Multi4 card using control materials (Detectabuse Stat-Skreen; Biochemical Diagnostics, Edgewood, NY, USA). The concentrations (-50%, -25%, +25%, +50% and 3× cut-off values) of the control materials were confirmed by mass spectrometry. Concordance rates were calculated around cut-offs. All devices showed high overall agreement rates of >90% with a few exceptions: the DxLINK exhibited lower sensitivity for benzoylecgonine, methadone and nortriptyline (60% and 30%, 92% and 40%, and 96% and 60% sensitivity at +50% and +25% cut-off levels, respectively). The E-Z Cup exhibited lower sensitivity for oxazepam and nortriptyline (97% and 50%, and 97% and 40% sensitivity at +50% and +25% cut-off levels, respectively). We additionally evaluated test-band color by visual inspection using a standard color-scale card. When detailed color criteria for determination of positivity were applied for the E-Z Cup, using slightly less stringent criteria, oxazepam, buprenorphine, MDMA and nortriptyline showed increases in sensitivity from 70-80% to 90-100%, all with a specificity above 98%. Overall, all devices exhibited satisfactory performance at ±50% cut-off levels for commonly used drugs, with the exception of lower sensitivity for cocaine testing for DxLINK. Careful evaluation of devices and elaborate calibration of visual interpretation for determining positivity may help improve the performance of these devices. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Rapid prototyping compliant arterial phantoms for in-vitro studies and device testing

PubMed Central

2013-01-01

Background Compliant vascular phantoms are desirable for in-vitro patient-specific experiments and device testing. TangoPlus FullCure 930® is a commercially available rubber-like material that can be used for PolyJet rapid prototyping. This work aims to gather preliminary data on the distensibility of this material, in order to assess the feasibility of its use in the context of experimental cardiovascular modelling. Methods The descending aorta anatomy of a volunteer was modelled in 3D from cardiovascular magnetic resonance (CMR) images and rapid prototyped using TangoPlus. The model was printed with a range of increasing wall thicknesses (0.6, 0.7, 0.8, 1.0 and 1.5 mm), keeping the lumen of the vessel constant. Models were also printed in both vertical and horizontal orientations, thus resulting in a total of ten specimens. Compliance tests were performed by monitoring pressure variations while gradually increasing and decreasing internal volume. Knowledge of distensibility was thus derived and then implemented with CMR data to test two applications. Firstly, a patient-specific compliant model of hypoplastic aorta suitable for connection in a mock circulatory loop for in-vitro tests was manufactured. Secondly, the right ventricular outflow tract (RVOT) of a patient necessitating pulmonary valve replacement was printed in order to physically test device insertion and assess patient’s suitability for percutaneous pulmonary valve intervention. Results The distensibility of the material was identified in a range from 6.5 × 10-3 mmHg-1 for the 0.6 mm case, to 3.0 × 10-3 mmHg-1 for the 1.5 mm case. The models printed in the vertical orientation were always more compliant than their horizontal counterpart. Rapid prototyping of a compliant hypoplastic aorta and of a RVOT anatomical model were both feasible. Device insertion in the RVOT model was successful. Conclusion Values of distensibility, compared with literature data, show that TangoPlus is suitable for manufacturing arterial phantoms, with the added benefit of being compatible with PolyJet printing, thus guaranteeing representative anatomical finishing, and quick and inexpensive fabrication. The appealing possibility of printing models of non-uniform wall thickness, resembling more closely certain physiological scenarios, can also be explored. However, this material appears to be too stiff for modelling the more compliant systemic venous system. PMID:23324211

Rapid prototyping compliant arterial phantoms for in-vitro studies and device testing.

PubMed

Biglino, Giovanni; Verschueren, Peter; Zegels, Raf; Taylor, Andrew M; Schievano, Silvia

2013-01-16

Compliant vascular phantoms are desirable for in-vitro patient-specific experiments and device testing. TangoPlus FullCure 930 is a commercially available rubber-like material that can be used for PolyJet rapid prototyping. This work aims to gather preliminary data on the distensibility of this material, in order to assess the feasibility of its use in the context of experimental cardiovascular modelling. The descending aorta anatomy of a volunteer was modelled in 3D from cardiovascular magnetic resonance (CMR) images and rapid prototyped using TangoPlus. The model was printed with a range of increasing wall thicknesses (0.6, 0.7, 0.8, 1.0 and 1.5 mm), keeping the lumen of the vessel constant. Models were also printed in both vertical and horizontal orientations, thus resulting in a total of ten specimens. Compliance tests were performed by monitoring pressure variations while gradually increasing and decreasing internal volume. Knowledge of distensibility was thus derived and then implemented with CMR data to test two applications. Firstly, a patient-specific compliant model of hypoplastic aorta suitable for connection in a mock circulatory loop for in-vitro tests was manufactured. Secondly, the right ventricular outflow tract (RVOT) of a patient necessitating pulmonary valve replacement was printed in order to physically test device insertion and assess patient's suitability for percutaneous pulmonary valve intervention. The distensibility of the material was identified in a range from 6.5 × 10(-3) mmHg(-1) for the 0.6 mm case, to 3.0 × 10(-3) mmHg(-1) for the 1.5 mm case. The models printed in the vertical orientation were always more compliant than their horizontal counterpart. Rapid prototyping of a compliant hypoplastic aorta and of a RVOT anatomical model were both feasible. Device insertion in the RVOT model was successful. Values of distensibility, compared with literature data, show that TangoPlus is suitable for manufacturing arterial phantoms, with the added benefit of being compatible with PolyJet printing, thus guaranteeing representative anatomical finishing, and quick and inexpensive fabrication. The appealing possibility of printing models of non-uniform wall thickness, resembling more closely certain physiological scenarios, can also be explored. However, this material appears to be too stiff for modelling the more compliant systemic venous system.

Measuring the triaxial load-deformation response of orthotropic materials subjected to large and small strain regimes

Treesearch

Edmond P. Saliklis; Steven M. Cramer; John C. Hermanson

1998-01-01

A new method for obtaining triaxial stress versus strain data is presented. The method tests cubic specimens and can provide constitutive data along three mutually perpendicular axes. Issues of removing the effects of boundary conditions in the proposed device are discussed. Two devices were constructed and used to obtain triaxial stress versus strain data on...

Flexible top-emitting OLEDs for lighting: bending limits

NASA Astrophysics Data System (ADS)

Schwamb, Philipp; Reusch, Thilo C.; Brabec, Christoph J.

2013-09-01

Flexible OLED light sources have great appeal due to new design options, being unbreakable and their low weight. Top-emitting OLED device architectures offer the broadest choice of substrate materials including metals which are robust, impermeable to humidity, and good thermal conductors making them promising candidates for flexible OLED device substrates. In this study, we investigate the bending limits of flexible top-emitting OLED lighting devices with transparent metal electrode and thin film encapsulation on a variety of both metal and plastic foils. The samples were subjected to concave and convex bending and inspected by different testing methods for the onset of breakdown for example visible defects and encapsulation failures. The critical failure modes were identified as rupture of the transparent thin metal top electrode and encapsulation for convex bending and buckling of the transparent metal top electrode for concave bending. We investigated influences from substrate material and thickness and top coating thickness. The substrate thickness is found to dominate bending limits as expected by neutral layer modeling. Coating shows strong improvements for all substrates. Bending radii <15mm are achieved for both convex and concave testing without damage to devices including their encapsulation.

NASA Tech Briefs, June 2009

NASA Technical Reports Server (NTRS)

2009-01-01

Topics covered include: Device for Measuring Low Flow Speed in a Duct, Measuring Thermal Conductivity of a Small Insulation Sample, Alignment Jig for the Precise Measurement of THz Radiation, Autoignition Chamber for Remote Testing of Pyrotechnic Devices, Microwave Power Combiners for Signals of Arbitrary Amplitude, Synthetic Foveal Imaging Technology, Airborne Antenna System for Minimum-Cycle-Slip GPS Reception, Improved Starting Materials for Back-Illuminated Imagers, Multi-Modulator for Bandwidth-Efficient Communication, Some Improvements in Utilization of Flash Memory Devices, GPS/MEMS IMU/Microprocessor Board for Navigation, T/R Multi-Chip MMIC Modules for 150 GHz, Pneumatic Haptic Interfaces, Device Acquires and Retains Rock or Ice Samples, Cryogenic Feedthrough Test Rig, Improved Assembly for Gas Shielding During Welding or Brazing, Two-Step Plasma Process for Cleaning Indium Bonding Bumps, Tool for Crimping Flexible Circuit Leads, Yb14MnSb11 as a High-Efficiency Thermoelectric Material, Polyimide-Foam/Aerogel Composites for Thermal Insulation, Converting CSV Files to RKSML Files, Service Management Database for DSN Equipment, Chemochromic Hydrogen Leak Detectors, Compatibility of Segments of Thermoelectric Generators, Complementary Barrier Infrared Detector, JPL Greenland Moulin Exploration Probe, Ultra-Lightweight Self-Deployable Nanocomposite Structure for Habitat Applications, and Room-Temperature Ionic Liquids for Electrochemical Capacitors.

Evaluation of SAGE Electrochromic Devices: Cooperative Research and Development Final Report, CRADA Number CRD-15-579

DOE Office of Scientific and Technical Information (OSTI.GOV)

Tenent, Robert C.

2017-12-06

NREL will conduct durability testing of Sage Electrochromics dynamic windows products using American Society for Testing and Materials (ASTM) standard methods and drive parameters as defined by Sage. Window units will be tested and standard analysis performed. Data will be summarized and reported back to Sage at the end of the testing period.

Room temperature triplet state spectroscopy of organic semiconductors.

PubMed

Reineke, Sebastian; Baldo, Marc A

2014-01-21

Organic light-emitting devices and solar cells are devices that create, manipulate, and convert excited states in organic semiconductors. It is crucial to characterize these excited states, or excitons, to optimize device performance in applications like displays and solar energy harvesting. This is complicated if the excited state is a triplet because the electronic transition is 'dark' with a vanishing oscillator strength. As a consequence, triplet state spectroscopy must usually be performed at cryogenic temperatures to reduce competition from non-radiative rates. Here, we control non-radiative rates by engineering a solid-state host matrix containing the target molecule, allowing the observation of phosphorescence at room temperature and alleviating constraints of cryogenic experiments. We test these techniques on a wide range of materials with functionalities spanning multi-exciton generation (singlet exciton fission), organic light emitting device host materials, and thermally activated delayed fluorescence type emitters. Control of non-radiative modes in the matrix surrounding a target molecule may also have broader applications in light-emitting and photovoltaic devices.

Modeling the effects of biological tissue on RF propagation from a wrist-worn device.

PubMed

Wilson, Jared D; Blanco, Justin A; Mazar, Scott; Bly, Mark

2014-01-01

Many wireless devices in common use today are worn either on or in close proximity to the body. Among them are a growing number of wrist-mounted devices designed for applications such as activity or vital-signs monitoring, typically using Bluetooth technology to communicate with external devices. Here, we use a tissue-mimicking phantom material in conjunction with anechoic chamber and network analyzer testing to investigate how antenna propagation patterns in one such device are influenced by the electrical properties of the human wrist. A microstrip antenna module is mounted onto phantom material of various geometries, and the resulting voltage standing wave ratio (VSWR), input impedance, and azimuth radiation pattern are recorded in both free space and real-world environments. The results of this study demonstrate how the high permittivity values of human tissue (ε(r) ≈ 16) affect the design parameters of microstrip antennas. A simulation environment using Sonnet EM software was used to further analyze the high dielectric effects of biological tissue on RF propagation.

Development of the laboratory prototype "CavyPool" for assessing treatments and materials for swimming pools.

PubMed

Valeriani, F; Gianfranceschi, G; Vitali, M; Protano, C; Romano Spica, V

2017-01-01

Hygiene and surveillance in swimming pools are established by WHO Guidelines and national laws. Progress in water management and pool construction is revolutionizing the field, introducing new materials, systems, disinfection procedures or monitoring markers. Innovation advances challenge the upgrading of safety and quality in pools and the appropriate implementation of guidelines. In order to provide a device for laboratory test, a prototype was realized and applied to study and compare swimming pool materials and treatments. A pool scale-model was engineered and evaluated by computational fluid dynamics algorithms. An automated real time monitoring assured steady state. Critical control points along the water circuit were made accessible to allow the placing of different biocides or water sampling. Simulations were safely performed in a standard hood. Materials for pool surfaces and pipelines were evaluated for biofilm formation under different disinfection conditions. Adherent microorganisms were assayed by mfDNA analysis using real time PCR. The prototype reached the steady state within 5-25 hours under different conditions, showing chemical, physical and fluid-dynamic stability. A method was optimized for testing materials showing their different response to biofilm induction. Several innovative PVC samples displayed highest resistance to bacterial adhesion. A device and method was developed for testing swimming pool hygienic parameters in laboratory. It allowed to test materials for pools hygiene and maintenance, including biofilm formation. It can be applied to simulate contaminations under different water treatments or disinfection strategies. It may support technical decisions and help policymakers in acquiring evidences for comparing or validating innovative solutions.

Defect-induced instability mechanisms of sputtered amorphous indium tin zinc oxide thin-film transistors

NASA Astrophysics Data System (ADS)

Park, Jinhee; Rim, You Seung; Li, Chao; Wu, Jiechen; Goorsky, Mark; Streit, Dwight

2018-04-01

We report the device performance and stability of sputtered amorphous indium-tin-zinc-oxide (ITZO) thin-film transistors as a function of oxygen ratio [O2/(Ar + O2)] during growth. Increasing the oxygen ratio enhanced the incorporation of oxygen during ITZO film growth and reduced the concentration of deep-level defects associated with oxygen vacancies. Under illumination with no bias stress, device stability and persistent photocurrent were improved with increased oxygen ratio. Bias stress tests of the devices were also performed with and without illumination. While high oxygen ratio growth conditions resulted in decreased deep-level oxygen vacancies in the ITZO material, the same conditions resulted in degradation of the interfacial layer between the ITZO channel and dielectric due to the migration of energetic oxygen ions to the interface. Therefore, when bias stress was applied, increased carrier trap density at the interface led to a decrease in device stability that offsets any improvement in the material itself. In order to take advantage of the improved ITZO material growth at a high oxygen ratio, the interface-related problems must be solved.

Threshold switching in SiGeAsTeN chalcogenide glass prepared by As ion implantation into sputtered SiGeTeN film

NASA Astrophysics Data System (ADS)

Liu, Guangyu; Wu, Liangcai; Song, Zhitang; Liu, Yan; Li, Tao; Zhang, Sifan; Song, Sannian; Feng, Songlin

2017-12-01

A memory cell composed of a selector device and a storage device is the basic unit of phase change memory. The threshold switching effect, main principle of selectors, is a universal phenomenon in chalcogenide glasses. In this work, we put forward a safe and controllable method to prepare a SiGeAsTeN chalcogenide film by implanting As ions into sputtered SiGeTeN films. For the SiGeAsTeN material, the phase structure maintains the amorphous state, even at high temperature, indicating that no phase transition occurs for this chalcogenide-based material. The electrical test results show that the SiGeAsTeN-based devices exhibit good threshold switching characteristics and the switching voltage decreases with the increasing As content. The decrease in valence alternation pairs, reducing trap state density, may be the physical mechanism for lower switch-on voltage, which makes the SiGeAsTeN material more applicable in selector devices through component optimization.

Material Testing Device

NASA Technical Reports Server (NTRS)

1993-01-01

Small Business Innovation Research (SBIR) contracts led to two commercial instruments and a new subsidiary for Physical Sciences, Inc. (PSI). The FAST system, originally developed for testing the effect of space environment on materials, is now sold commercially for use in aging certification of materials intended for orbital operation. The Optical Temperature Monitor was designed for precise measurement of high temperatures on certain materials to be manufactured in space. The original research was extended to the development of a commercial instrument that measures and controls fuel gas temperatures in industrial boilers. PSI created PSI Environmental Instruments to market the system. The company also offers an Aerospace Measurement Service that has evolved from other SBIR contracts.

Characterization of pi-Conjugated Polymers for Transistor and Photovoltaic Applications

NASA Astrophysics Data System (ADS)

Paulsen, Bryan D.

pi-Conjugated polymers represent a unique class of optoelectronic materials. Being polymers, they are solution processable and inherently "soft" materials. This makes them attractive candidates for the production of roll-to-roll printed electronic devices on flexible substrates. The optical and electronic properties of pi-conjugated polymers are synthetically tunable allowing material sets to be tailored to specific applications. Two of the most heavily researched applications are the thin film transistor, the building block of electronic circuits, and the bulk heterojunction solar cell, which holds great potential as a renewable energy source. Key to developing commercially feasible pi-conjugated polymer devices is a thorough understanding of the electronic structure and charge transport behavior of these materials in relationship with polymer structure. Here this structure property relationship has been investigated through electrical and electrochemical means in concert with a variety of other characterization techniques and device test beds. The tunability of polymer optical band gap and frontier molecular orbital energy level was investigated in systems of vinyl incorporating statistical copolymers. Energy levels and band gaps are crucial parameters in developing efficient photovoltaic devices, with control of these parameters being highly desirable. Additionally, charge transport and density of electronic states were investigated in pi-conjugated polymers at extremely high electrochemically induced charge density. Finally, the effects of molecular weight on pi-conjugated polymer optical properties, energy levels, charge transport, morphology, and photovoltaic device performance was examined.

Frequency Rectification Applied to Piezoelectric Energy Harvesting and Improving Available Power of Piezoelectric Motors

NASA Astrophysics Data System (ADS)

Kuroda, Kazuaki; LCGT Collaboration

Piezoelectric materials are just now, within the last decade, coming into their own as a commercial material. Capable of converting energy from the mechanical domain to the electrical domain; piezos are ideal sensors, vibration dampers, energy harvesters, and actuators. Frequency rectification, or the conversion of small, high frequency piezoelectric vibrations into useful low frequency actuation, is required to obtain widespread industrial use of piezoelectric devices. This work examines three manifestations of piezoelectric frequency rectification: energy harvesting, a hydraulic motor, and friction based commercial-off-the-shelf motors. An energy harvesting device is developed, manufactured, and tested in this work, resulting in the development of a high Energy Density (J/m 3), high Power Density (W/m3) energy harvester. The device is shown to have an Energy Density nearly twice that of a similar conventional energy harvesting device. The result of this work is the development of an energy harvesting system that generates more energy in a given volume of piezoelectric material, opening the possibility of miniaturization of energy harvesting devices. Also presented is an effort to integrate a high frequency, high flow rate micromachined valve array into a PiezoHydraulic Pump (PHP), enabling resonant operation of the PHP. Currently, the device is limited by the resonant frequency of the proprietary passive check valves. The PHP is fully characterized, and the microvalve array is tested to determine its resonant frequency in a fluid medium. The valve testing resulted in a resonant frequency of 6.9 kHz, slightly lower than the target operating frequency of 10 kHz. Finally, the results of an examination of frequency rectification as applied to COTS piezoelectric motors are presented. Currently, motors are almost universally characterized based upon their available mechanical power. A better comparison is one based upon the actual Energy Density of the piezoelectric material utilized in the motor compared to the theoretical maximum Energy Density under the motor operating conditions (i.e., frequency, applied electric field). The result of this work is a more descriptive metric to evaluate piezoelectric motors that provides information on the effectiveness of the motor drive train; that is, how effectively the motion of the piezoelectric is transferred to the outside world.

40 CFR 65.160 - Performance test and TRE index value determination records.

Code of Federal Regulations, 2010 CFR

2010-07-01

... concentration of TOC or regulated material is determined. (1) Nonflare combustion device. Where an owner or... TOC achieved by the incinerator determined as specified in § 65.158(b)(4), as applicable, or the concentration of regulated material or TOC (parts per million by volume, by compound) determined as specified in...

40 CFR 63.997 - Performance test and compliance assessment requirements for control devices.

Code of Federal Regulations, 2010 CFR

2010-07-01

... as TOC minus methane and ethane according to the procedures specified. (i) Selection of sampling... regulated material or TOC, sampling sites shall be located as specified in paragraphs (e)(2)(i)(A)(1) and (e... shall ensure the measurement of total organic regulated material or TOC (minus methane and ethane...

49 CFR 572.190 - Incorporated materials.

Code of Federal Regulations, 2014 CFR

2014-10-01

... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST DEVICES SID-IIsD Side Impact Crash... procedures manual entitled, “Procedures for Assembly, Disassembly, and Inspection (PADI) of the SID-IIsD Side...

49 CFR 572.190 - Incorporated materials.

Code of Federal Regulations, 2013 CFR

2013-10-01

... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST DEVICES SID-IIsD Side Impact Crash... procedures manual entitled, “Procedures for Assembly, Disassembly, and Inspection (PADI) of the SID-IIsD Side...

42 CFR 85a.3 - Authority for investigations of places of employment.

Code of Federal Regulations, 2010 CFR

2010-10-01

..., conditions, structures, machines, apparatus, devices, equipment, and materials within the place of employment; and to conduct medical examinations, anthropometric measurements and functional tests of employees...

Degradable phosphate glass fiber reinforced polymer matrices: mechanical properties and cell response.

PubMed

Brauer, Delia S; Rüssel, Christian; Vogt, Sebastian; Weisser, Jürgen; Schnabelrauch, Matthias

2008-01-01

The development of biodegradable materials for internal fracture fixation is of great interest, as they would both eliminate the problem of stress shielding and obviate the need for a second operation to remove fixation devices. Preliminary investigations for the production of degradable fiber reinforced polymer composite materials are detailed. Composites were produced of phosphate invert glass fibers of the glass system P(2)O(5)-CaO-MgO-Na(2)O-TiO(2), which showed a low solubility in previous work. The fibers were embedded into a matrix of a degradable organic polymer network based on methacrylate-modified oligolactide. Fracture behavior, bending strength and elastic modulus were evaluated during 3-point bending tests and the fracture surface of the composites was investigated using a scanning electron microscope. Short-term biocompatibility was tested in an FDA/EtBr viability assay using MC3T3-E1 murine pre-osteoblast cells and showed a good cell compatibility of the composite materials. Results suggested that these composite materials are biocompatible and show mechanical properties which are of interest for the production of degradable bone fixation devices.

An assessment of surface emissivity variation effects on plasma uniformity analysis using IR cameras

NASA Astrophysics Data System (ADS)

Greenhalgh, Abigail; Showers, Melissa; Biewer, Theodore

2017-10-01

The Prototype-Material Plasma Exposure eXperiment (Proto-MPEX) is a linear plasma device operating at Oak Ridge National Laboratory (ORNL). Its purpose is to test plasma source and heating concepts for the planned Material Plasma Exposure eXperiment (MPEX), which has the mission to test the plasma-material interactions under fusion reactor conditions. In this device material targets will be exposed to high heat fluxes (>10 MW/m2). To characterize the heat fluxes to the target a IR thermography system is used taking up to 432 frames per second videos. The data is analyzed to determine the surface temperature on the target in specific regions of interest. The IR analysis has indicated a low level of plasma uniformity; the plasma often deposits more heat to the edge of the plate than the center. An essential parameter for IR temperature calculation is the surface emissivity of the plate (stainless steel). A study has been performed to characterize the variation in the surface emissivity of the plate as its temperature changes and its surface finish is modified by plasma exposure.

30 CFR 18.20 - Quality of material, workmanship, and design.

Code of Federal Regulations, 2011 CFR

2011-07-01

... TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES... facilitate inspection and maintenance. (b) MSHA will test only electrical equipment that in the opinion of... shall be accessible for field inspection, where practicable. (e) An audible warning device shall be...

30 CFR 18.20 - Quality of material, workmanship, and design.

Code of Federal Regulations, 2010 CFR

2010-07-01

... TESTING, EVALUATION, AND APPROVAL OF MINING PRODUCTS ELECTRIC MOTOR-DRIVEN MINE EQUIPMENT AND ACCESSORIES... facilitate inspection and maintenance. (b) MSHA will test only electrical equipment that in the opinion of... shall be accessible for field inspection, where practicable. (e) An audible warning device shall be...

A Holographic Prism Based on Photo-Thermo-Refractive Glass: Requirements and Possibilities

NASA Astrophysics Data System (ADS)

Angervaks, A. E.; Gorokhovskii, K. S.; Granovskii, V. A.; Van Bac, Doan; Ivanov, S. A.; Okun', R. A.; Nikonorov, N. V.; Ryskin, A. I.

2017-12-01

A technology for multivalued holographic measurement of a plane angle—a holographic prism, which serves as the basis for a device for calibrating the testing tools for navigational equipment under rolling— has been developed. The holographic prism is a miniature sample of photosensitive material, which contains a system of superimposed holographic gratings, and a laser the radiation of which passes through gratings to form a fan of diffracted beams. The fan in a prism based on a calcium fluoride (fluorite) crystal with color centers contained six out-of-plane beams radiating from a region with a hard-to-localize center. This fact hindered calibration of the measure and its application in the testing device. The use of photothermo-refractive glass as a material for preparing a sample and recording a system of holograms in it makes it possible to eliminate the drawbacks of fluorite-based prism. The number of holograms rises up to 21, the fan becomes in-plane, and its center is localized in a small region, with a size of several tenths of the sample thickness (1-2 mm). The fan beams are energetically homogeneous, and each can be identified when using the fan in a testing device.

The design and development of a high-throughput magneto-mechanostimulation device for cartilage tissue engineering.

PubMed

Brady, Mariea A; Vaze, Reva; Amin, Harsh D; Overby, Darryl R; Ethier, C Ross

2014-02-01

To recapitulate the in vivo environment and create neo-organoids that replace lost or damaged tissue requires the engineering of devices, which provide appropriate biophysical cues. To date, bioreactors for cartilage tissue engineering have focused primarily on biomechanical stimulation. There is a significant need for improved devices for articular cartilage tissue engineering capable of simultaneously applying multiple biophysical (electrokinetic and mechanical) stimuli. We have developed a novel high-throughput magneto-mechanostimulation bioreactor, capable of applying static and time-varying magnetic fields, as well as multiple and independently adjustable mechanical loading regimens. The device consists of an array of 18 individual stations, each of which uses contactless magnetic actuation and has an integrated Hall Effect sensing system, enabling the real-time measurements of applied field, force, and construct thickness, and hence, the indirect measurement of construct mechanical properties. Validation tests showed precise measurements of thickness, within 14 μm of gold standard calliper measurements; further, applied force was measured to be within 0.04 N of desired force over a half hour dynamic loading, which was repeatable over a 3-week test period. Finally, construct material properties measured using the bioreactor were not significantly different (p=0.97) from those measured using a standard materials testing machine. We present a new method for articular cartilage-specific bioreactor design, integrating combinatorial magneto-mechanostimulation, which is very attractive from functional and cost viewpoints.

Some metal oxides and their applications for creation of Microsystems (MEMS) and Energy Harvesting Devices (EHD)

NASA Astrophysics Data System (ADS)

Denishev, K.

2016-10-01

This is a review of a part of the work of the Technological Design Group at Technical University of Sofia, Faculty of Electronic Engineering and Technologies, Department of Microelectronics. It is dealing with piezoelectric polymer materials and their application in different microsystems (MEMS) and Energy Harvesting Devices (EHD), some organic materials and their applications in organic (OLED) displays, some transparent conductive materials etc. The metal oxides Lead Zirconium Titanate (PZT) and Zinc Oxide (ZnO) are used as piezoelectric layers - driving part of different sensors, actuators and EHD. These materials are studied in term of their performance in dependence on the deposition conditions and parameters. They were deposited as thin films by using RF Sputtering System. As technological substrates, glass plates and Polyethylenetherephtalate (PET) foils were used. For characterization of the materials, a test structure, based on Surface Acoustic Waves (SAW), was designed and prepared. The layers were characterized by Fourier Transform Infrared spectroscopy (FTIR). The piezoelectric response was tested at variety of mechanical loads (tensile strain, stress) in static and dynamic (multiple bending) mode. The single-layered and double-layered structures were prepared for piezoelectric efficiency increase. A structure of piezoelectric energy transformer is proposed and investigated.

Development and mechanical properties of structural materials from lunar simulant

NASA Technical Reports Server (NTRS)

Desai, Chandra S.

1991-01-01

Development of versatile engineering materials from locally available materials in space is an important step toward establishment of outposts such as on the moon and Mars. Here development of the technologies for manufacture of structural and construction materials on the moon, utilizing local lunar soil (regolith), without the use of water, is an important element for habitats and explorations in space. It is also vital that the mechanical behavior such as strength and flexural properties, fracture toughness, ductility, and deformation characteristics are defined toward establishment of the ranges of engineering applications of the materials developed. The objectives include two areas: (1) thermal liquefaction of lunar simulant (at about 1100 C) with different additives (fibers, powders, etc.); and (2) development and use of a traxial test device in which lunar simulants are first compacted under cycles of loading, and then tested with different vacuums and initial confining or insitu stress. The second area was described in previous progress reports and publications; since the presently available device allows vacuum levels up to only 10(exp -4) torr, it is recommended that a vacuum pump that can allow higher levels of vacuum is acquired.

Comparison of hardness of three temporary filling materials cured by two light-curing devices.

PubMed

Bodrumlu, E; Koçak, M M; Hazar Bodrumlu, E; Ozcan, S; Koçak, S

2014-01-01

Polymerization ability of light-curing devices can affect the light-cured material hardness. The purpose of the present study was to evaluate and compare the hardness of three temporary filling materials that had been light-cured by either a light emitting diode (LED) or a halogen light-curing unit. The temporary filling materials, First Fill, Voco Clip and Bioplic, were placed in wells in a Teflon plate. The 24 specimens of each material were divided into two groups (N.=12/group) for photo-activation by either of the two light-curing units. The LED or halogen device was applied for 40s to the top surface of each specimen. A Knoop hardness test was performed on the top and bottom surface of each specimen, with five measurements per specimen. The highest hardness values for both the LED and halogen treated groups were observed for First Fill and the lowest values were for Voco Clip in top and bottom surfaces. The hardness obtained for the three materials with the halogen unit were significantly higher than the values obtained with the LED unit in both surfaces (P<0.05). First Fill light-cured temporary material exhibited the highest hardness values on the top and bottom surfaces than Voco Clip and Bioplic temporary materials. The hardness of light-cured temporary filling materials can be affected by the type of light-curing unit.

Proton Testing: Opportunities, Pitfalls and Puzzles

NASA Technical Reports Server (NTRS)

Ladbury, Raymond

2017-01-01

Although proton SEE testing can place constraints on some heavy-ion SEE susceptibilities, it is important to quantify residual risk that protons may not reveal all SEE susceptibilities in a system. We examine the relative strengths and limitations of proton and heavy-ion SEE testing and how these may be affected by technology scaling and high-Z materials in the device.

46 CFR 160.047-5 - Inspections and tests. 1

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 6 2010-10-01 2010-10-01 false Inspections and tests. 1 160.047-5 Section 160.047-5... and Child § 160.047-5 Inspections and tests. 1 1 The manufacturer of a personal flotation device must... labeled buoyant vests shall— (1) Maintain quality control of the materials used, the manufacturing methods...

46 CFR 160.047-5 - Inspections and tests. 1

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 6 2011-10-01 2011-10-01 false Inspections and tests. 1 160.047-5 Section 160.047-5... and Child § 160.047-5 Inspections and tests. 1 1 The manufacturer of a personal flotation device must... labeled buoyant vests shall— (1) Maintain quality control of the materials used, the manufacturing methods...

High temperature aqueous stress corrosion testing device

DOEpatents

Bornstein, A.N.; Indig, M.E.

1975-12-01

A description is given of a device for stressing tensile samples contained within a high temperature, high pressure aqueous environment, thereby permitting determination of stress corrosion susceptibility of materials in a simple way. The stressing device couples an external piston to an internal tensile sample via a pull rod, with stresses being applied to the sample by pressurizing the piston. The device contains a fitting/seal arrangement including Teflon and weld seals which allow sealing of the internal system pressure and the external piston pressure. The fitting/seal arrangement allows free movement of the pull rod and the piston.

Plasma facing materials and components for future fusion devices—development, characterization and performance under fusion specific loading conditions

NASA Astrophysics Data System (ADS)

Linke, J.

2006-04-01

The plasma exposed components in existing and future fusion devices are strongly affected by the plasma material interaction processes. These mechanisms have a strong influence on the plasma performance; in addition they have major impact on the lifetime of the plasma facing armour and the joining interface between the plasma facing material (PFM) and the heat sink. Besides physical and chemical sputtering processes, high heat quasi-stationary fluxes during normal and intense thermal transients are of serious concern for the engineers who develop reliable wall components. In addition, the material and component degradation due to intense fluxes of energetic neutrons is another critical issue in D-T-burning fusion devices which requires extensive R&D. This paper presents an overview on the materials development and joining, the testing of PFMs and components, and the analysis of the neutron irradiation induced degradation.

21 CFR 872.3660 - Impression material.

Code of Federal Regulations, 2011 CFR

2011-04-01

...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3660 Impression material. (a) Identification. Impression material is a device composed of materials such as alginate or polysulfide intended to be placed... device is intended to provide models for study and for production of restorative prosthetic devices, such...

21 CFR 872.3660 - Impression material.

Code of Federal Regulations, 2010 CFR

2010-04-01

...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3660 Impression material. (a) Identification. Impression material is a device composed of materials such as alginate or polysulfide intended to be placed... device is intended to provide models for study and for production of restorative prosthetic devices, such...

New Applications of the Human Whole Blood Pyrogen Assay (PyroCheck).

PubMed

Fennrich; Wendel; Hartung

1999-01-01

The absence of pyrogens in injectable drugs is an indispensable safety control because contaminants causing fever pose a life-threatening risk to the patient resulting in the worst case in death by shock. When fever- inducing agents, i.e.pyrogens, come into contact with the immunocompetent cells in blood, these cells release mediators which transmit the fever signal to the thermoregulatory centre of the brain. The Phamocopoeia lists currently two test systems for pyrogenicity: 1. The in vivo rabbit pyrogen test which measures the fever reaction following injection of the sample to the animals. 2. The in vitro Limulus Amebocyte Lysate assay (LAL) which measures the coagulation in a lysate prepared from the blood of the horseshoe crab specifically initiated by endotoxins, i.e. cell wall components from Gram-negative bacteria. The new test presented here (PyroCheck) exploits the reaction of monocytes/macrophages for the detection of pyrogens: human whole blood taken from healthy volunteers is incubated in the presence of the test sample in any form, be it a solution, a powder or even solid material. Pyrogenic contaminations initiate the release of the "endogenous pyrogen" Interleukin-1beta determined by ELISA after a fixed incubation time. The technology presently listed in the Pharmacopoeia is limited to parenteralia (rabbit test: biologicals and pharmaceuticals, LAL: predominantly pharmaceuticals). In the EU Medical Devices Directive from 1995 the rabbit pyrogen test for medical products is in some cases requested. (in some cases LAL of an eluate from the device). However, pyrogen-testing needs to cover also innovative high-tech products such as medical devices (implants, medical plastic materials, dialysis machines), cellular therapies and species-specific agents (e.g. recombinant proteins). Here we report that the human blood test PyroCheck is suitable for testing filters in air quality control as well as for assessing medical devices and biocompatibility (dialysate fluid), i.e. that it can be extended to a wide spectrum of applications.

Development and mechanical properties of construction materials from lunar simulant

NASA Technical Reports Server (NTRS)

Desai, Chandra S.

1992-01-01

Development of versatile engineering materials from locally available materials in space is an important step toward the establishment of outposts on the Moon and Mars. Development of the technologies for manufacture of structural and construction materials on the Moon, utilizing local lunar soil (regolith), without the use of water, is an important element for habitats and explorations in space. It is also vital that the mechanical behavior such as strength and tensile, flexural properties, fracture toughness, ductility, and deformation characteristics are defined toward establishment of the ranges of engineering applications of the materials developed. The objectives include two areas: (1) thermal 'liquefaction' of lunar simulant (at about 1100 C) with different additives (fibers, powders, etc.), and (2) development and use of a new triaxial test device in which lunar simulants are first compacted under cycles of loading, and then tested with different vacuums and initial confining or in situ stress. Details of the development of intermediate ceramic composites (ICC) and testing for their flexural and compression characteristics were described in various reports and papers. The subject of behavior of compacted simulant under vacuum was described in previous progress reports and publications; since the presently available device allows vacuum levels up to only 10(exp -4) torr, it is recommended that a vacuum pump that can allow higher levels of vacuum be utilized for further investigation.

Newly Elaborated Multipurpose Polymer Electrolyte Encompassing RTILs for Smart Energy-Efficient Devices.

PubMed

Nair, Jijeesh R; Porcarelli, Luca; Bella, Federico; Gerbaldi, Claudio

2015-06-17

Profoundly ion-conducting, self-standing, and tack-free ethylene oxide-based polymer electrolytes encompassing a room-temperature ionic liquid (RTIL) with specific amounts of lithium salt are successfully prepared via a rapid and easily upscalable process including a UV irradiation step. All prepared materials are thoroughly characterized in terms of their physical, chemical, and morphological properties and eventually galvanostatically cycled in lab-scale lithium batteries (LIBs) exploiting a novel direct polymerization procedure to get intimate electrode/electrolyte interfacial characteristics. The promising multipurpose characteristics of the newly elaborated materials are demonstrated by testing them in dye-sensitized solar cells (DSSCs), where the introduction of the iodine/iodide-based redox mediator in the polymer matrix assured the functioning of a lab-scale test cell with conversion efficiency exceeding 6% at 1 sun. The reported results enlighten the promising prospects of the material to be successfully implemented as stable, durable, and efficient electrolyte in next-generation energy conversion and storage devices.

Evacuation of coal from hoppers/silos with low pressure pneumatic blasting systems

NASA Technical Reports Server (NTRS)

Fischer, J. S.

1977-01-01

The need for an efficient, economical, effective and quiet device for moving coal and other difficult bulk solids was recognized. Thus came the advent of the low pressure pneumatic blasting system - a very efficient means of using a small amount of plant air (up to 125 PSI) to eliminate the most troublesome material hang-ups in storage containers. This simple device has one moving part and uses approximately 3% of the air consumed by a pneumatic vibrator on the same job. The principle of operation is very simple: air stored in the unit's reservoir is expelled directly into the material via a patented quick release valve. The number, size, and placement of the blaster units on the storage vessel is determined by a series of tests to ascertain flowability of the problem material. These tests in conjunction with the hopper or silo configuration determine specification of a low pressure pneumatic blasting system. This concept has often proven effective in solving flow problems when all other means have failed.

Neutron-diffraction measurement of residual stresses in Al-Cu cold-cut welding

NASA Astrophysics Data System (ADS)

Fiori, F.; Marcantoni, M.

Usually, when it is necessary to join different materials with a large difference in their melting points, welding should be avoided. To overcome this problem we designed and built a device to obtain cold-cut welding, which is able to strongly decrease oxidation problems of the surfaces to be welded. Thanks to this device it is possible to achieve good joining between different pairs of materials (Al-Ti, Cu-Al, Cu-Al alloys) without reaching the material melting point. The mechanical and microstructural characterisation of the joining and the validation of its quality were obtained using several experimental methods. In particular, in this work neutron-diffraction experiments for the evaluation of residual stresses in Cu-Al junctions are described, carried out at the G5.2 diffractometer of LLB, Saclay. Neutron-diffraction results are presented and related to other experimental tests such as microstructural characterisation (through optical and scanning electron microscopy) and mechanical characterisation (tensile-strength tests) of the welded interface.

Experimental Thermal Performance Testing of Cryogenic Tank Systems and Materials

NASA Technical Reports Server (NTRS)

Myers, Wesley C.; Fesmire, J. E.

2018-01-01

A comparative study was conducted to collect and analyze thermal conductivity data on a wide variety of low density materials, as well as thermal performance data on a number of vacuum-jacketed cryogenic tank systems. Although a vast number of these types of materials and cryogenic tank systems exist, the thermal conductivity of insulation materials and the thermal performance of cryogenic tank systems is often difficult to compare because many industrial methods and experimental conditions are available and utilized. The availability of a new thermal conductivity measurement device, the Macroflash Cup Cryostat, which is applicable for assessing a variety of materials, is accessible at NASA's Cryogenic Test Laboratory (CTL) at the Kennedy Space Center (KSC). The convenience of this device has resulted in the ability to rapidly measure the thermal conductivity properties of these materials by using a flat-plate liquid nitrogen (LN2) boiloff technique that employs a guarded heat flow test methodology in order to determine the effective thermal conductivity (ke) of a test specimen. As the thermal conductivities are measured at cryogenic temperatures, materials suitable for both future space missions and cryogenic tank systems can be identified and experimentally analyzed. Also recognizable are materials which may help increase energy efficiency by limiting the thermal losses encountered under various environmental conditions. The overall focus of this work consisted of two parts. One part, was to produce and analyze thermal conductivity data on a wide variety of materials with suitable properties conducive to those needed to aid in the production of a calibration curve for the "low end" of the Macroflash instrument. (Low end meaning materials with a thermal conductivity rating below 100 milliwatts per meter-Kelvin). The second part was to collect and analyze heat transfer data for a variety of small vacuum-jacketed vessels (cryogenic tank systems) in order to compare the thermal performance between them.

Automatic robotic arm operations and sampling in near zero gravity environment - functional tests results from Phobos-Grunt mission

NASA Astrophysics Data System (ADS)

Kozlova, Tatiana; Karol Seweryn, D..; Grygorczuk, Jerzy; Kozlov, Oleg

The sample return missions have made a very significant progress to understanding of geology, the extra-terrestrial materials, processes occurring on surface and subsurface level, as well as of interactions between such materials and mechanisms operating there. The various sample return missions in the past (e.g. Apollo missions, Luna missions, Hayabusa mission) have provided scientists with samples of extra-terrestrial materials allowing to discover answers to critical scientific questions concerning the origin and evolution of the Solar System. Several new missions are currently planned: sample return missions, e.g Russian Luna-28, ESA Phootprint and MarcoPolo-R as well as both robotic and manned exploration missions to the Moon and Mars. One of the key challenges in such missions is the reliable sampling process which can be achieved by using many different techniques, e.g. static excavating technique (scoop), core drilling, sampling using dynamic mechanisms (penetrators), brushes and pneumatic systems. The effectiveness of any sampling strategy depends on many factors, including the required sample size, the mechanical and chemical soil properties (cohesive, hard or porous regolith, stones), the environment conditions (gravity, temperature, pressure, radiation). Many sampling mechanism have been studied, designed and built in the past, two techniques to collect regolith samples were chosen for the Phobos-Grunt mission. The proposed system consisted of a robotic arm with a 1,2m reach beyond the lander (IKI RAN); a tubular sampling device designed for collecting both regolith and small rock fragments (IKI RAN); the CHOMIK device (CBK PAN) - the low velocity penetrator with a single-sample container for collecting samples from the rocky surface. The functional tests were essential step in robotic arm, sampling device and CHOMIK device development process in the frame of Phobos-Grunt mission. Three major results were achieved: (i) operation scenario for autonomous sampling; (ii) technical characteristics of both devices, i.e. progress cycles of CHOMIK device in different materials and torque in the manipulator joints during sampling operations; (iii) confirmation of applicability of both devices to perform such type of tasks. The phases in operational scenario were prepared to meet mission and system requirements mainly connected with: (i) environment (near zero gravity, vacuum, dust), (ii) safety and (iii) to avoid common operation of both devices at the same time.

Study of silicone-based materials for the packaging of optoelectronic devices

NASA Astrophysics Data System (ADS)

Lin, Yeong-Her

The first part of this work is to evaluate the main materials used for the packaging of high power light-emitting diodes (LEDs), i.e., the die attach materials, the encapsulant materials, and high color rendering index(CRI) sol-gel composite materials. All of these materials had been discussed the performance, reliability, and issues in high power LED packages. High power white LEDs are created either from blue or near-ultraviolet chips encapsulated with a yellow phosphor, or from red-green-blue LED light mixing systems. The phosphor excited by blue LED chip was mostly used in experiment of this dissertation. The die attach materials contains filler particles possessing a maximum particle size less than 1.5 mum in diameter blended with epoxy polymer matrix. Such compositions enable thin bond line thickness, which decreases thermal resistance that exists between thermal interface materials and the corresponding mating surfaces. The thermal conductivity of nano silver die attach materials is relatively low, the thermal resistance from the junction to board is just 1.6 KW-1 in the bond line thickness of 5.3 mum, which is much lower than the thermal resistance using conventional die attach materials. The silicone die attach adhesive made in the lab cures through the free radical reaction of epoxy-functional organopolysiloxane and through the hydrosilylation reaction between alkenyl-functional organopolysiloxane and silicone-boned hydrogen-functional organopolysiloxane. By the combination of the free radical reaction and the hydrosilylation reaction, the low-molecular-weight silicone oil will not be out-migrated and not contaminate wire bondability to the LED chip and lead frame. Hence, the silicone die attach adhesive made in the lab can pass all reliability tests, such as operating life test JEDEC 85°C/85RH and room temperature operating life test. For LED encapsulating materials, most of commercial silicone encapsulants still suffer thermal/radiation induced degradations, and thus cause reliability issues and shorten the lifetime. A new high performance silicone has been developed and its performance has been compared with other commercial silicone products in the packaging of high power white LEDs. The high performance silicone also has better results than commercial high refractive index silicone and optical grade epoxy under JEDEC reliability standard for moisture sensitivity test. In synthesis of red dye-doped particles by sol-gel method, it is a novel method to get high color rendering index (CRI) LEDs. These red dye-doped particles, with average diameter of 5 mum, can be mixed with liquid encapsulants to form a uniform distribution in polymer matrix. The red dye-doped particles can be excited by phosphor-emitted yellow light instead of blue light from LED chip. Therefore, warm white LEDs with high CRI can be gotten at high lumen efficiency. The second part of this work is silicone elastomer for biomedical applications, especially in making urological implantable devices. A cross-linked, heat curable, addition-reaction silicone material is prepared. The material may be molded or formed into one or more medical devices. One such medical device could be a catheter used in urological applications. The material is a long term indwelling material that resists encrustation like a metal stent, but is more comfortable because it is silicone-based. The material can be made relatively cheaply compared to metal stents. Furthermore, the material is biocompatible with bladder epithelial cells.

Impact of radiations on the electromechanical properties of materials and on the piezoresistive and capacitive transduction mechanisms used in microsystems

NASA Astrophysics Data System (ADS)

Francis, Laurent A.; Gkotsis, Petros; Kilchytska, Valeriya; Tang, Xiaohui; Druart, Sylvain; Raskin, Jean-Pierre; Flandre, Denis

2013-03-01

The impact of different types of radiation on the electromechanical properties of materials used in microfabrication and on the capacitive and piezoresistive transduction mechanisms of MEMS is investigated. MEMS technologies could revolutionize avionics, satellite and space applications provided that the stress conditions which can compromise the reliability of microsystems in these environments are well understood. Initial tests with MEMS revealed a vulnerability of some types of devices to radiation induced dielectric charging, a physical mechanism which also affects microelectronics, however integration of novel functional materials in microfabrication and the current trend to substitute SiO2 with high-k dielectrics in ICs pose new questions regarding reliability in radiation environments. The performance of MEMS devices with moving parts could also degrade due to radiation induced changes in the mechanical properties of the materials. It is thus necessary to investigate the effects of radiation on the properties of thin films used in microfabrication and here we report on tests with γ, high energy protons and fast neutrons radiation. Prototype SOI based MEMS magnetometers which were developed in UCL are also used as test vehicles to investigate radiation effects on the reliability of magnetically actuated and capacitively coupled MEMS.

OFF-SITE ENVIRONMENTAL MONITORING REPORT: RADIATION MONITORING AROUND UNITED STATES NUCLEAR TEST AREAS, CALENDAR YEAR 1986

EPA Science Inventory

The principal activity at the NTS is testing of nuclear devices, though other related projects are also conducted. The principal activities of the Off-Site Radiological Safety Program are routine environmental monitoring for radioactive materials in various media and for radiatio...

Assessment of in situ test technology for construction control of base courses and embankments.

DOT National Transportation Integrated Search

2008-04-01

The main objective of this research is to assess the use of three nondestructive testing devices, the GeoGauge, the LFWD, and the DCP, in order to evaluate the in situ elastic modulus of highway materials for application in the quality assurance/qual...

KENNEDY SPACE CENTER, FLA. - Dr. Paul Hintze (left) explains to Center Director Jim Kennedy a project he is working at the KSC Beach Corrosion Test Site. Hitze is doing post-graduate work for the National Research Council. The test facility site was established in the 1960s and has provided more than 30 years of historical information on the long-term performance of many materials in use at KSC and other locations around the world. Located 100 feet from the Atlantic Ocean approximately 1 mile south of the Space Shuttle launch sites, the test facility includes an atmospheric exposure site, a flowing seawater exposure site, and an on-site electrochemistry laboratory and monitoring station. The beach laboratory is used to conduct real-time corrosion experiments and provides for the remote monitoring of surrounding weather conditions. The newly added flowing seawater immersion facility provides for the immersion testing of materials and devices under controlled conditions.

NASA Image and Video Library

2003-08-21

KENNEDY SPACE CENTER, FLA. - Dr. Paul Hintze (left) explains to Center Director Jim Kennedy a project he is working at the KSC Beach Corrosion Test Site. Hitze is doing post-graduate work for the National Research Council. The test facility site was established in the 1960s and has provided more than 30 years of historical information on the long-term performance of many materials in use at KSC and other locations around the world. Located 100 feet from the Atlantic Ocean approximately 1 mile south of the Space Shuttle launch sites, the test facility includes an atmospheric exposure site, a flowing seawater exposure site, and an on-site electrochemistry laboratory and monitoring station. The beach laboratory is used to conduct real-time corrosion experiments and provides for the remote monitoring of surrounding weather conditions. The newly added flowing seawater immersion facility provides for the immersion testing of materials and devices under controlled conditions.

Optical isolators for 2-micron fibre lasers

NASA Astrophysics Data System (ADS)

Stevens, Gary; Legg, Thomas H.; Shardlow, Peter

2015-02-01

We report on the development and testing of optical isolators for use in 2-micron fiber laser systems. A variety of potential Faraday rotator materials were characterised to identify the most suitable materials for use in the 1700-2100nm wavelength range. Isolators based on the three best performing materials were then developed and packaged as fiber-in, fiber-out and fiber-in, beam-out devices. The isolators were then tested in CW, pulsed and ultrafast laser systems. The three different designs produced different performance characteristics, but all designs demonstrated isolation >25dB and insertion losses of <1.2 dB.

27 CFR 24.36 - Instruments and measuring devices.

Code of Federal Regulations, 2013 CFR

2013-04-01

... to be furnished by the proprietor for the purpose of testing and measuring wine, spirits, volatile fruit-flavor concentrate, and materials will be maintained by the proprietor in accurate and readily...

27 CFR 24.36 - Instruments and measuring devices.

Code of Federal Regulations, 2012 CFR

2012-04-01

... to be furnished by the proprietor for the purpose of testing and measuring wine, spirits, volatile fruit-flavor concentrate, and materials will be maintained by the proprietor in accurate and readily...

27 CFR 24.36 - Instruments and measuring devices.

Code of Federal Regulations, 2011 CFR

2011-04-01

... to be furnished by the proprietor for the purpose of testing and measuring wine, spirits, volatile fruit-flavor concentrate, and materials will be maintained by the proprietor in accurate and readily...

27 CFR 24.36 - Instruments and measuring devices.

Code of Federal Regulations, 2010 CFR

2010-04-01

... to be furnished by the proprietor for the purpose of testing and measuring wine, spirits, volatile fruit-flavor concentrate, and materials will be maintained by the proprietor in accurate and readily...

27 CFR 24.36 - Instruments and measuring devices.

Code of Federal Regulations, 2014 CFR

2014-04-01

... to be furnished by the proprietor for the purpose of testing and measuring wine, spirits, volatile fruit-flavor concentrate, and materials will be maintained by the proprietor in accurate and readily...

Rapid and low-cost hot-embossing of polycaprolactone microfluidic devices

NASA Astrophysics Data System (ADS)

Fan, Yiqiang; Liu, Shicheng; He, Jianyun; Gao, Kexin; Zhang, Yajun

2018-01-01

Polycaprolactone (PCL) is a low-cost biocompatible and biodegradable material which is highly suitable for the short-live applications like microfluidics in the biological and medical field. In this study, a rapid and low-cost microfabrication technique for PCL-based microfluidic devices is proposed, the SU-8 mold fabricated on the silicon substrate was used for the hot-embossing of microstructures on PCL. Since PCL after the molding process is optically non-transparent, to improve the visibility of the fluid in the microfluidic device and enclosing the microchannel, a transparency adhesive film which originally used for the sealing of PCR well-plate is used for the sealing of the microchannels embossed on PCL substrate. The profile of the fabricated microchannels was carefully characterized, the bonding strength is tested and several PCL-based microfluidic devices were also fabricated and tested for demonstration.

Design, Manufacturing and Characterization of Functionally Graded Flextensional Piezoelectric Actuators

NASA Astrophysics Data System (ADS)

Amigo, R. C. R.; Vatanabe, S. L.; Silva, E. C. N.

2013-03-01

Previous works have been shown several advantages in using Functionally Graded Materials (FGMs) for the performance of flextensional devices, such as reduction of stress concentrations and gains in reliability. In this work, the FGM concept is explored in the design of graded devices by using the Topology Optimization Method (TOM), in order to determine optimal topologies and gradations of the coupled structures of piezoactuators. The graded pieces are manufactured by using the Spark Plasma Sintering (SPS) technique and are bonded to piezoelectric ceramics. The graded actuators are then tested by using a modular vibrometer system for measuring output displacements, in order to validate the numerical simulations. The technological path developed here represents the initial step toward the manufacturing of an integral piezoelectric device, constituted by piezoelectric and non-piezoelectric materials without bonding layers.

InSb charge coupled infrared imaging device: The 20 element linear imager

NASA Technical Reports Server (NTRS)

Thom, R. D.; Koch, T. L.; Parrish, W. J.; Langan, J. D.; Chase, S. C.

1980-01-01

The design and fabrication of the 8585 InSb charge coupled infrared imaging device (CCIRID) chip are reported. The InSb material characteristics are described along with mask and process modifications. Test results for the 2- and 20-element CCIRID's are discussed, including gate oxide characteristics, charge transfer efficiency, optical mode of operation, and development of the surface potential diagram.

Design Evaluation of High Reliability Lithium Batteries

NASA Technical Reports Server (NTRS)

Buchman, R. C.; Helgeson, W. D.; Istephanous, N. S.

1985-01-01

Within one year, a lithium battery design can be qualified for device use through the application of accelerated discharge testing, calorimetry measurements, real time tests and other supplemental testing. Materials and corrosion testing verify that the battery components remain functional during expected battery life. By combining these various methods, a high reliability lithium battery can be manufactured for applications which require zero defect battery performance.

Re-entry simulation chamber for thermo-mechanical characterisation of space materials

NASA Astrophysics Data System (ADS)

Liedtke, Volker

2003-09-01

During re-entry, materials and components are subject to very high thermal and mechanical loads. Any failure may cause loss of mission. Therefore, materials and components have to be tested under most rigid conditions to verify the suitability of the material and to verify the design of the components. The Re-Entry Simulation Chamber (RESiC) at ARC Seibersdorf research (ARCS) allows simulating the high thermal loads as well as complex mechanical load profiles that may occur during a re-entry; additionally, the influence of chemical reactions of materials with gaseous components of the atmosphere can be studied. The high vacuum chamber (better than 1×10-6 mbar) has a diameter of 650 mm and allows a sample height of 500 mm, or 1000 mm with extension flange. The gas dosing system is designed to emulate the increasing atmospheric pressure during the re-entry trajectory of a vehicle. Heating is performed by a 30 kW induction generator that allows a sufficiently rapid heating of larger components; electrically conductive materials such as metals or carbon fibre reinforced ceramics are directly heated, while for electrical insulators, susceptor plates or tubes will be employed. The uniaxial servo-hydraulic testing machine has a maximum load of 70 kN, either static or with a frequency of up to 70 Hz, with any given load profile (sinus, rectangular, triangular, ...). Strain measurements will be done by non-contacting laser speckle system for maximum flexibility and minimum instrumentation time effort (currently under application testing), or by strain gauges. All relevant process parameters are controlled and recorded by microcomputer. The highly sophisticated control software allows a convenient and reliable multi-channel data acquisition, e.g. temperatures at various positions of the test piece, pressure, loads, strains, and any other test data according to customer specifications; the data format is suitable for any further data processing. During the set-up and operation testing, the device has successfully been employed for thermal shock testing, thermal cycling and gas cycling tests, thermomechanical tests and combinations thereof, e.g. sintering or hot-pressing. During the current final test series, the device will be completed, further optimised and shall be fully operational in summer 2003.

Radiation Characterization of Commercial GaN Devices

NASA Technical Reports Server (NTRS)

Harris, Richard D.; Scheick, Leif Z.; Hoffman, James P.; Thrivikraman, Tushar; Jenabi, Masud; Gim, Yonggyu; Miyahira, Tetsuo

2011-01-01

Radiative feedback from primordial protostars and final mass of the first star Commercially available devices fabricated from GaN are beginning to appear from a number of different suppliers. Based on previous materials and prototype device studies, it is expected that these commercial devices will be quite tolerant to the types of radiation encountered in space. This expectation needs to be verified and the study described herein was undertaken for that purpose. All of the parts discussed in this report are readily available commercially. The parts chosen for study are all targeted for RF applications. Three different studies were performed: 1) a preliminary DDD/TID test of a variety of part types was performed by irradiating with 50 MeV protons, 2) a detailed DDD/TID study of one particular part type was performed by irradiating with 50 MeV protons, and 3) a SEB/SEGR test was performed on a variety of part types by irradiating with heavy ions. No significant degradation was observed in the tests performed in this study.

Foldable and Cytocompatible Sol-gel TiO2 Photonics

NASA Astrophysics Data System (ADS)

Li, Lan; Zhang, Ping; Wang, Wei-Ming; Lin, Hongtao; Zerdoum, Aidan B.; Geiger, Sarah J.; Liu, Yangchen; Xiao, Nicholas; Zou, Yi; Ogbuu, Okechukwu; Du, Qingyang; Jia, Xinqiao; Li, Jingjing; Hu, Juejun

2015-09-01

Integrated photonics provides a miniaturized and potentially implantable platform to manipulate and enhance the interactions between light and biological molecules or tissues in in-vitro and in-vivo settings, and is thus being increasingly adopted in a wide cross-section of biomedical applications ranging from disease diagnosis to optogenetic neuromodulation. However, the mechanical rigidity of substrates traditionally used for photonic integration is fundamentally incompatible with soft biological tissues. Cytotoxicity of materials and chemicals used in photonic device processing imposes another constraint towards these biophotonic applications. Here we present thin film TiO2 as a viable material for biocompatible and flexible integrated photonics. Amorphous TiO2 films were deposited using a low temperature (<250 °C) sol-gel process fully compatible with monolithic integration on plastic substrates. High-index-contrast flexible optical waveguides and resonators were fabricated using the sol-gel TiO2 material, and resonator quality factors up to 20,000 were measured. Following a multi-neutral-axis mechanical design, these devices exhibit remarkable mechanical flexibility, and can sustain repeated folding without compromising their optical performance. Finally, we validated the low cytotoxicity of the sol-gel TiO2 devices through in-vitro cell culture tests. These results demonstrate the potential of sol-gel TiO2 as a promising material platform for novel biophotonic devices.

Electrical Characterization of Semiconductor Materials and Devices

NASA Astrophysics Data System (ADS)

Deen, M.; Pascal, Fabien

Semiconductor materials and devices continue to occupy a preeminent technological position due to their importance when building integrated electronic systems used in a wide range of applications from computers, cell-phones, personal digital assistants, digital cameras and electronic entertainment systems, to electronic instrumentation for medical diagnositics and environmental monitoring. Key ingredients of this technological dominance have been the rapid advances made in the quality and processing of materials - semiconductors, conductors and dielectrics - which have given metal oxide semiconductor device technology its important characteristics of negligible standby power dissipation, good input-output isolation, surface potential control and reliable operation. However, when assessing material quality and device reliability, it is important to have fast, nondestructive, accurate and easy-to-use electrical characterization techniques available, so that important parameters such as carrier doping density, type and mobility of carriers, interface quality, oxide trap density, semiconductor bulk defect density, contact and other parasitic resistances and oxide electrical integrity can be determined. This chapter describes some of the more widely employed and popular techniques that are used to determine these important parameters. The techniques presented in this chapter range in both complexity and test structure requirements from simple current-voltage measurements to more sophisticated low-frequency noise, charge pumping and deep-level transient spectroscopy techniques.

Foldable and Cytocompatible Sol-gel TiO2 Photonics

PubMed Central

Li, Lan; Zhang, Ping; Wang, Wei-Ming; Lin, Hongtao; Zerdoum, Aidan B.; Geiger, Sarah J.; Liu, Yangchen; Xiao, Nicholas; Zou, Yi; Ogbuu, Okechukwu; Du, Qingyang; Jia, Xinqiao; Li, Jingjing; Hu, Juejun

2015-01-01

Integrated photonics provides a miniaturized and potentially implantable platform to manipulate and enhance the interactions between light and biological molecules or tissues in in-vitro and in-vivo settings, and is thus being increasingly adopted in a wide cross-section of biomedical applications ranging from disease diagnosis to optogenetic neuromodulation. However, the mechanical rigidity of substrates traditionally used for photonic integration is fundamentally incompatible with soft biological tissues. Cytotoxicity of materials and chemicals used in photonic device processing imposes another constraint towards these biophotonic applications. Here we present thin film TiO2 as a viable material for biocompatible and flexible integrated photonics. Amorphous TiO2 films were deposited using a low temperature (<250 °C) sol-gel process fully compatible with monolithic integration on plastic substrates. High-index-contrast flexible optical waveguides and resonators were fabricated using the sol-gel TiO2 material, and resonator quality factors up to 20,000 were measured. Following a multi-neutral-axis mechanical design, these devices exhibit remarkable mechanical flexibility, and can sustain repeated folding without compromising their optical performance. Finally, we validated the low cytotoxicity of the sol-gel TiO2 devices through in-vitro cell culture tests. These results demonstrate the potential of sol-gel TiO2 as a promising material platform for novel biophotonic devices. PMID:26344823

Foldable and Cytocompatible Sol-gel TiO2 Photonics.

PubMed

Li, Lan; Zhang, Ping; Wang, Wei-Ming; Lin, Hongtao; Zerdoum, Aidan B; Geiger, Sarah J; Liu, Yangchen; Xiao, Nicholas; Zou, Yi; Ogbuu, Okechukwu; Du, Qingyang; Jia, Xinqiao; Li, Jingjing; Hu, Juejun

2015-09-07

Integrated photonics provides a miniaturized and potentially implantable platform to manipulate and enhance the interactions between light and biological molecules or tissues in in-vitro and in-vivo settings, and is thus being increasingly adopted in a wide cross-section of biomedical applications ranging from disease diagnosis to optogenetic neuromodulation. However, the mechanical rigidity of substrates traditionally used for photonic integration is fundamentally incompatible with soft biological tissues. Cytotoxicity of materials and chemicals used in photonic device processing imposes another constraint towards these biophotonic applications. Here we present thin film TiO2 as a viable material for biocompatible and flexible integrated photonics. Amorphous TiO2 films were deposited using a low temperature (<250 °C) sol-gel process fully compatible with monolithic integration on plastic substrates. High-index-contrast flexible optical waveguides and resonators were fabricated using the sol-gel TiO2 material, and resonator quality factors up to 20,000 were measured. Following a multi-neutral-axis mechanical design, these devices exhibit remarkable mechanical flexibility, and can sustain repeated folding without compromising their optical performance. Finally, we validated the low cytotoxicity of the sol-gel TiO2 devices through in-vitro cell culture tests. These results demonstrate the potential of sol-gel TiO2 as a promising material platform for novel biophotonic devices.

Revealing Optical Components

NASA Technical Reports Server (NTRS)

2002-01-01

The Optical Vector Analyzer (OVA) 1550 significantly reduces the time and cost of testing sophisticated optical components. The technology grew from the research Luna Technologies' Dr. Mark Froggatt conducted on optical fiber strain measurement while working at Langley Research Center. Dr. Froggatt originally developed the technology for non- destructive evaluation testing at Langley. The new technique can provide 10,000 independent strain measurements while adding less than 10 grams to the weight of the vehicle. The OVA is capable of complete linear characterization of single-mode optical components used in high- bit-rate applications. The device can test most components over their full range in less than 30 seconds, compared to the more than 20 minutes required by other testing methods. The dramatically shortened measurement time results in increased efficiency in final acceptance tests of optical devices, and the comprehensive data produced by the instrument adds considerable value for component consumers. The device eliminates manufacturing bottlenecks, while reducing labor costs and wasted materials during production.

76 FR 72983 - Agency Information Collection Activities: Proposed Collection; Comment Request

Federal Register 2010, 2011, 2012, 2013, 2014

2011-11-28

... byproduct material in certain devices. General licensees are required to keep testing records and submit... use of automated collection techniques or other forms of information technology? The public may...

10 CFR 36.1 - Purpose and scope.

Code of Federal Regulations, 2010 CFR

2010-01-01

... area subject to irradiation are contained within a device and are not accessible by personnel), medical radiology or teletherapy, radiography (the irradiation of materials for nondestructive testing purposes), gauging, or open-field (agricultural) irradiations. ...

10 CFR 36.1 - Purpose and scope.

Code of Federal Regulations, 2012 CFR

2012-01-01

... area subject to irradiation are contained within a device and are not accessible by personnel), medical radiology or teletherapy, radiography (the irradiation of materials for nondestructive testing purposes), gauging, or open-field (agricultural) irradiations. ...

10 CFR 36.1 - Purpose and scope.

Code of Federal Regulations, 2013 CFR

2013-01-01

... area subject to irradiation are contained within a device and are not accessible by personnel), medical radiology or teletherapy, radiography (the irradiation of materials for nondestructive testing purposes), gauging, or open-field (agricultural) irradiations. ...

10 CFR 36.1 - Purpose and scope.

Code of Federal Regulations, 2011 CFR

2011-01-01

... area subject to irradiation are contained within a device and are not accessible by personnel), medical radiology or teletherapy, radiography (the irradiation of materials for nondestructive testing purposes), gauging, or open-field (agricultural) irradiations. ...

Heat storage capability of a rolling cylinder using Glauber's salt

NASA Technical Reports Server (NTRS)

Herrick, C. S.; Zarnoch, K. P.

1980-01-01

The rolling cylinder phase change heat storage concept was developed to the point where a prototype design is completed and a cost analysis is prepared. A series of experimental and analytical tasks are defined to establish the thermal, mechanical, and materials behavior of rolling cylinder devices. These tasks include: analyses of internal and external heat transfer; performance and lifetime testing of the phase change materials; corrosion evaluation; development of a mathematical model; and design of a prototype and associated test equipment.

A high throughput mechanical screening device for cartilage tissue engineering.

PubMed

Mohanraj, Bhavana; Hou, Chieh; Meloni, Gregory R; Cosgrove, Brian D; Dodge, George R; Mauck, Robert L

2014-06-27

Articular cartilage enables efficient and near-frictionless load transmission, but suffers from poor inherent healing capacity. As such, cartilage tissue engineering strategies have focused on mimicking both compositional and mechanical properties of native tissue in order to provide effective repair materials for the treatment of damaged or degenerated joint surfaces. However, given the large number design parameters available (e.g. cell sources, scaffold designs, and growth factors), it is difficult to conduct combinatorial experiments of engineered cartilage. This is particularly exacerbated when mechanical properties are a primary outcome, given the long time required for testing of individual samples. High throughput screening is utilized widely in the pharmaceutical industry to rapidly and cost-effectively assess the effects of thousands of compounds for therapeutic discovery. Here we adapted this approach to develop a high throughput mechanical screening (HTMS) system capable of measuring the mechanical properties of up to 48 materials simultaneously. The HTMS device was validated by testing various biomaterials and engineered cartilage constructs and by comparing the HTMS results to those derived from conventional single sample compression tests. Further evaluation showed that the HTMS system was capable of distinguishing and identifying 'hits', or factors that influence the degree of tissue maturation. Future iterations of this device will focus on reducing data variability, increasing force sensitivity and range, as well as scaling-up to even larger (96-well) formats. This HTMS device provides a novel tool for cartilage tissue engineering, freeing experimental design from the limitations of mechanical testing throughput. © 2013 Published by Elsevier Ltd.

Discuss the testing problems of ultraviolet irradiance meters

NASA Astrophysics Data System (ADS)

Ye, Jun'an; Lin, Fangsheng

2014-09-01

Ultraviolet irradiance meters are widely used in many areas such as medical treatment, epidemic prevention, energy conservation and environment protection, computers, manufacture, electronics, ageing of material and photo-electric effect, for testing ultraviolet irradiance intensity. So the accuracy of value directly affects the sterile control in hospital, treatment, the prevention level of CDC and the control accuracy of curing and aging in manufacturing industry etc. Because the display of ultraviolet irradiance meters is easy to change, in order to ensure the accuracy, it needs to be recalibrated after being used period of time. By the comparison with the standard ultraviolet irradiance meters, which are traceable to national benchmarks, we can acquire the correction factor to ensure that the instruments working under accurate status and giving the accurate measured data. This leads to an important question: what kind of testing device is more accurate and reliable? This article introduces the testing method and problems of the current testing device for ultraviolet irradiance meters. In order to solve these problems, we have developed a new three-dimensional automatic testing device. We introduce structure and working principle of this system and compare the advantages and disadvantages of two devices. In addition, we analyses the errors in the testing of ultraviolet irradiance meters.

Noninvasive ultrasonic examination technology in support of counter-terrorism and drug interdiction activities: the acoustic inspection device (AID)

NASA Astrophysics Data System (ADS)

Diaz, Aaron A.; Burghard, Brion J.; Skorpik, James R.; Shepard, Chester L.; Samuel, Todd J.; Pappas, Richard A.

2003-07-01

The Pacific Northwest National Laboratory (PNNL) has developed a portable, battery-operated, handheld ultrasonic device that provides non-invasive container interrogation and material identification capabilities. The technique governing how the acoustic inspection device (AID) functions, involves measurements of ultrasonic pulses (0.1 to 5 MHz) that are launched into a container or material. The return echoes from these pulses are analyzed in terms of time-of-flight and frequency content to extract physical property measurements (the acoustic velocity and attenuation coefficient) of the material under test. The AID performs an automated analysis of the return echoes to identify the material, and detect contraband in the form of submerged packages and concealed compartments in liquid filled containers and solid-form commodities. An inspector can quickly interrogate outwardly innocuous commodity items such as shipping barrels, tanker trucks, and metal ingots. The AID can interrogate container sizes ranging from approximately 6 inches in diameter to over 96 inches in diameter and allows the inspector to sort liquid and material types into groups of like and unlike; a powerful method for discovering corrupted materials or miss-marked containers co-mingled in large shipments. This manuscript describes the functionality, capabilities and measurement methodology of the technology as it relates to homeland security applications.

Erosion tests of materials by energetic particle beams

DOE Office of Scientific and Technical Information (OSTI.GOV)

Schechter, D.E.; Tsai, C.C.; Sluss, F.

1985-01-01

The internal components of magnetic fusion devices must withstand erosion from and high heat flux of energetic plasma particles. The selection of materials for the construction of these components is important to minimize contamination of the plasma. In order to study various materials' comparative resistance to erosion by energetic particles and their ability to withstand high heat flux, water-cooled copper swirl tubes coated or armored with various materials were subjected to bombardment by hydrogen and helium particle beams. Materials tested were graphite, titanium carbide (TiC), chromium, nickel, copper, silver, gold, and aluminum. Details of the experimental arrangement and methods ofmore » application or attachment of the materials to the copper swirl tubes are presented. Results including survivability and mass losses are discussed.« less

Additive-Free Transparent Triarylamine-Based Polymeric Hole-Transport Materials for Stable Perovskite Solar Cells.

PubMed

Matsui, Taisuke; Petrikyte, Ieva; Malinauskas, Tadas; Domanski, Konrad; Daskeviciene, Maryte; Steponaitis, Matas; Gratia, Paul; Tress, Wolfgang; Correa-Baena, Juan-Pablo; Abate, Antonio; Hagfeldt, Anders; Grätzel, Michael; Nazeeruddin, Mohammad Khaja; Getautis, Vytautas; Saliba, Michael

2016-09-22

Triarylamine-based polymers with different functional groups were synthetized as hole-transport materials (HTMs) for perovskite solar cells (PSCs). The novel materials enabled efficient PSCs without the use of chemical doping (or additives) to enhance charge transport. Devices employing poly(triarylamine) with methylphenylethenyl functional groups (V873) showed a power conversion efficiency of 12.3 %, whereas widely used additive-free poly[bis(4-phenyl)(2,4,6-trimethylphenyl)amine] (PTAA) demonstrated 10.8 %. Notably, devices with V873 enabled stable PSCs under 1 sun illumination at maximum power point tracking for approximately 40 h at room temperature, and in the dark under elevated temperature (85 °C) for more than 140 h. This is in stark contrast to additive-containing devices, which degrade significantly within the same time frame. The results present remarkable progress towards stable PSC under real working conditions and industrial stress tests. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Long-life mission reliability for outer planet atmospheric entry probes

NASA Technical Reports Server (NTRS)

Mccall, M. T.; Rouch, L.; Maycock, J. N.

1976-01-01

The results of a literature analysis on the effects of prolonged exposure to deep space environment on the properties of outer planet atmospheric entry probe components are presented. Materials considered included elastomers and plastics, pyrotechnic devices, thermal control components, metal springs and electronic components. The rates of degradation of each component were determined and extrapolation techniques were used to predict the effects of exposure for up to eight years to deep space. Pyrotechnic devices were aged under accelerated conditions to an equivalent of eight years in space and functionally tested. Results of the literature analysis of the selected components and testing of the devices indicated that no severe degradation should be expected during an eight year space mission.

FAST BUS Test Box (LAIKA) (Engineering Materials)

DOE Office of Scientific and Technical Information (OSTI.GOV)

Not Available

1983-01-01

The assembly drawing AD 135-518-00-RO, and the drawings referenced thereon, provide the data and specifications for constructing the LAIKA Test Box. Some drawings are not available, although they are listed on the material lists included. The assembly is a manual tester for FAST BUS modules, both masters and slaves. FAST BUS signals are generated by means of switches or push buttons and provide the state of the bus lines by lighting LED's. The box acts as either a master or slave - depending upon the module under test. It also acts as an ATC to test the arbitration logic ofmore » a master or ATC device.« less

Determination of Thermoelectric Module Efficiency A Survey

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, Hsin; McCarty, Robin; Salvador, James R.

2014-01-01

The development of thermoelectrics (TE) for energy conversion is in the transition phase from laboratory research to device development. There is an increasing demand to accurately determine the module efficiency, especially for the power generation mode. For many thermoelectrics, the figure of merit, ZT, of the material sometimes cannot be fully realized at the device level. Reliable efficiency testing of thermoelectric modules is important to assess the device ZT and provide the end-users with realistic values on how much power can be generated under specific conditions. We conducted a general survey of efficiency testing devices and their performance. The resultsmore » indicated the lack of industry standards and test procedures. This study included a commercial test system and several laboratory systems. Most systems are based on the heat flow meter method and some are based on the Harman method. They are usually reproducible in evaluating thermoelectric modules. However, cross-checking among different systems often showed large errors that are likely caused by unaccounted heat loss and thermal resistance. Efficiency testing is an important area for the thermoelectric community to focus on. A follow-up international standardization effort is planned.« less

A comparative evaluation of polymerization stress data obtained with four different mechanical testing systems.

PubMed

Gonçalves, Flávia; Boaro, Leticia C; Ferracane, Jack L; Braga, Roberto R

2012-06-01

The null hypothesis was that mechanical testing systems used to determine polymerization stress (σ(pol)) would rank a series of composites similarly. Two series of composites were tested in the following systems: universal testing machine (UTM) using glass rods as bonding substrate, UTM/acrylic rods, "low compliance device", and single cantilever device ("Bioman"). One series had five experimental composites containing BisGMA:TEGDMA in equimolar concentrations and 60, 65, 70, 75 or 80 wt% of filler. The other series had five commercial composites: Filtek Z250 (3M ESPE), Filtek A110 (3M ESPE), Tetric Ceram (Ivoclar), Heliomolar (Ivoclar) and Point 4 (Kerr). Specimen geometry, dimensions and curing conditions were similar in all systems. σ(pol) was monitored for 10 min. Volumetric shrinkage (VS) was measured in a mercury dilatometer and elastic modulus (E) was determined by three-point bending. Shrinkage rate was used as a measure of reaction kinetics. ANOVA/Tukey test was performed for each variable, separately for each series. For the experimental composites, σ(pol) decreased with filler content in all systems, following the variation in VS. For commercial materials, σ(pol) did not vary in the UTM/acrylic system and showed very few similarities in rankings in the others tests system. Also, no clear relationships were observed between σ(pol) and VS or E. The testing systems showed a good agreement for the experimental composites, but very few similarities for the commercial composites. Therefore, comparison of polymerization stress results from different devices must be done carefully. Copyright © 2012 Academy of Dental Materials. Published by Elsevier Ltd. All rights reserved.

Testing fireproof materials in a combustion chamber

NASA Astrophysics Data System (ADS)

Kulhavy, Petr; Martinec, Tomas; Novak, Ondrej; Petru, Michal; Srb, Pavel

This article deals with a prototype concept, real experiment and numerical simulation of a combustion chamber, designed for testing fire resistance some new insulating composite materials. This concept of a device used for testing various materials, providing possibility of monitoring temperatures during controlled gas combustion. As a fuel for the combustion process propane butane mixture has been used and also several kinds of burners with various conditions of inlet air (forced, free) and fuel flows were tested. The tested samples were layered sandwich materials based on various materials or foams, used as fillers in fire shutters. The temperature distribution was measured by using thermocouples. A simulation of whole concept of experimental chamber has been carried out as the non-premixed combustion process in the commercial final volume sw Pyrosim. The result was to design chamber with a construction suitable, according to the international standards, achieve the required values (temperature in time). Model of the combustion based on a stoichiometric defined mixture of gas and the tested layered samples showed good conformity with experimental results - i.e. thermal distribution inside and heat release rate that has gone through the sample.

Interfacial characterization of flexible hybrid electronics

NASA Astrophysics Data System (ADS)

Najafian, Sara; Amirkhizi, Alireza V.; Stapleton, Scott

2018-03-01

Flexible Hybrid Electronics (FHEs) are the new generation of electronics combining flexible plastic film substrates with electronic devices. Besides the electrical features, design improvements of FHEs depend on the prediction of their mechanical and failure behavior. Debonding of electronic components from the flexible substrate is one of the most common and critical failures of these devices, therefore, the experimental determination of material and interface properties is of great importance in the prediction of failure mechanisms. Traditional interface characterization involves isolated shear and normal mode tests such as the double cantilever beam (DCB) and end notch flexure (ENF) tests. However, due to the thin, flexible nature of the materials and manufacturing restrictions, tests mirroring traditional interface characterization experiments may not always be possible. The ideal goal of this research is to design experiments such that each mode of fracture is isolated. However, due to the complex nonlinear nature of the response and small geometries of FHEs, design of the proper tests to characterize the interface properties can be significantly time and cost consuming. Hence numerical modeling has been implemented to design these novel characterization experiments. This research involves loading case and specimen geometry parametric studies using numerical modeling to design future experiments where either shear or normal fracture modes are dominant. These virtual experiments will provide a foundation for designing similar tests for many different types of flexible electronics and predicting the failure mechanism independent of the specific FHE materials.

21 CFR 862.1055 - Newborn screening test system for amino acids, free carnitine, and acylcarnitines using tandem...

Code of Federal Regulations, 2012 CFR

2012-04-01

... mass spectrometry is a device that consists of stable isotope internal standards, control materials..., free carnitine, and acylcarnitines using tandem mass spectrometry. 862.1055 Section 862.1055 Food and... screening test system for amino acids, free carnitine, and acylcarnitines using tandem mass spectrometry. (a...

21 CFR 862.1055 - Newborn screening test system for amino acids, free carnitine, and acylcarnitines using tandem...

Code of Federal Regulations, 2014 CFR

2014-04-01

... mass spectrometry is a device that consists of stable isotope internal standards, control materials..., free carnitine, and acylcarnitines using tandem mass spectrometry. 862.1055 Section 862.1055 Food and... screening test system for amino acids, free carnitine, and acylcarnitines using tandem mass spectrometry. (a...

21 CFR 872.3670 - Resin impression tray material.

Code of Federal Regulations, 2010 CFR

2010-04-01

... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3670 Resin impression tray material. (a) Identification. Resin impression tray material is a device intended for use in a two-step dental mold fabricating process. The device consists of a resin material, such as methyl methacrylate, and is used to form a...

21 CFR 872.3670 - Resin impression tray material.

Code of Federal Regulations, 2011 CFR

2011-04-01

... (CONTINUED) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3670 Resin impression tray material. (a) Identification. Resin impression tray material is a device intended for use in a two-step dental mold fabricating process. The device consists of a resin material, such as methyl methacrylate, and is used to form a...

Endotoxin Detection in Pharmaceuticals and Medical Devices with Kinetic-QCL, a Kinetic-Quantitative Chromogenic Limulus Amebocyte Lysate Assay.

PubMed

Berzofsky, Ronald N.

1995-01-01

The observation that endotoxin caused gelation in extracts of Limulus amebocytes has been expanded to the development of an in vitro kinetic, quantitative chromogenic LAL assay (Kinetic-QCL) for the detection of endotoxin in aqueous fluids. Within the last 15 years, the use of Limulus amebocyte lysate to detect and control the presence of pyrogenic substances in pharmaceuticals and medical devices has gained wide international acceptance. Both the United States and European Pharmacopoeias contain descriptions of and requirements for the LAL Bacterial Endotoxin Test. Both pharmacopoeias have begun to remove the rabbit pyrogen test requirement in a majority of drug monographs and have substituted endotoxin limits to be determined by LAL. The use of LAL has proved invaluable in controlling the level of endotoxin in finished product. The endotoxin contribution of raw materials and packaging material can be monitored as well. In-process testing at critical production steps can identify additional sources of endotoxin contamination, and depyrogenation processes can be validated by quantitating the degradation of endotoxin challenges. The speed, reproducibility, sensitivity, and economics of the Kinetic-QCL assay, in conjunction with the ppropriate equipment and software, over both the in vivo rabbit pyrogen test and the more traditional LAL gel-clot assay allow a more in-depth approach to the control of endotoxin in pharmaceuticals and medical devices.

Environmental test program for superconducting materials and devices

NASA Technical Reports Server (NTRS)

Haertling, Gene; Randolph, Henry; Hsi, Chi-Shiung; Verbelyi, Darren

1992-01-01

A systematic approach to obtaining real time, superconducting YBa2Cu30(7-x) materials is presented. The work was carried out under the overall direction of Clemson University with tasks being performed at both Clemson and Westinghouse (Aiken, SC). Clemson prepared the tapecast superconducting 123 material and fabricated in into substrate-supported, environmentally-protected conducting links. Following this, all of the elements were individually tested for resistance vs. temperature and Tc; and then a portion of them were kept at Clemson for further testing while a randomly selected group was delivered to Westinghouse for specialized testing and evaluation in their low temperature/high vacuum and radiation facilities. In addition, a number of control samples (12 ea.) were put on the shelf at Clemson for further reference at the end of the testing period. The specific tests conducted at Clemson and Westinghouse/SRC are presented with a summary of the results.

Comparison of mechanical properties of multi-walled carbon nanotube and graphene nanosheet/polyethylene oxide composites plasticized with lithium triflate

NASA Astrophysics Data System (ADS)

Jurkane, A.; Gaidukov, S.

2017-10-01

A strong engineering interest in nanostructured conducting polymers and its composite materials have been widely used to build various sensor devices, electronic interconnect devices, fuel cells and batteries. Preparation of polymeric nano-composites with finely controlled structure, especially, at nano-scale, is still one of the most perspective modification ways of the properties of polymeric composites. Multi-walled carbon nanotube (MWCNT)/polyethylene oxide (PEO) and graphene nanosheets (GR)/PEO composites and composite of MWCNT/GR/PEO were prepared by solution casting and hot-pressing method. Composites were plasticized by 5% of Lithium triflate (LiTrifl), which play role of additional ion source in conducting polymer composite. Mechanical tensile tests were performed to evaluate nanoparticles influence on the mechanical strength of the conductive polymer composite materials. Difference of tensile tests of prepared composition can be seen from tensile tests data curves. The results of tensile tests indicated that the nanoparticles can provide PEO/5%LiTrifl composite with stiffening effects at rather low filler content (at least 0.05% by volume).

Laboratory and field evaluation of hot mix asphalt with high contents of reclaimed asphalt pavement

NASA Astrophysics Data System (ADS)

Van Winkle, Clinton Isaac

Currently in Iowa, the amount of RAP materials allowed for the surface layer is limited to 15% by weight. The objective of this project was to develop quality standards for inclusion of RAP content higher than 15% in asphalt mixtures. To meet Superpave mix design requirements, it was necessary to fractionate the RAP materials. Based on the extensive sieve-by-sieve analysis of RAP materials, the optimum sieve size to fractionate RAP materials was identified. To determine if the higher percentage of RAP materials than 15% can be used in Iowa's state highway, three test sections with 30.0%, 35.5% and 39.2% of RAP materials were constructed on Highway 6 in Iowa City. The construction of the field test sections was monitored and the cores were obtained to measure field densities of test sections. Field mixtures collected from test sections were compacted in the laboratory in order to test the moisture sensitivity using a Hamburg Wheel Tracking Device. The binder was extracted from the field mixtures with varying amounts of RAP materials and tested to determine the effects of RAP materials on the PG grade of a virgin binder. Field cores were taken from the various mix designs to determine the percent density of each test section. A condition survey of the test sections was then performed to evaluate the short-term performance.

A flexible pressure responsive device based on the interaction between silver nanoparticles and an aluminum reflector

NASA Astrophysics Data System (ADS)

Rankin, Alasdair; McGarry, Steven

2018-01-01

The unique and tunable optical properties of metal nanoparticles have attracted intense and sustained academic attention in recent years. In tandem with the demand for low-cost responsive materials, one particular topic of interest is the development of mechanically responsive device structures. This work describes the design, fabrication, and testing of a mechanically responsive plasmonic device structure that has been integrated onto a standard commercial plastic substrate. With a low actuation force and a visually perceivable color shift, this device would be attractive for applications requiring responsive features that can be activated by the human hand.

Combustion products generating and metering device

NASA Technical Reports Server (NTRS)

Wiberg, R. E.; Klisch, J. A. (Inventor)

1971-01-01

An apparatus for generating combustion products at a predetermined fixed rate, mixing the combustion products with air to achieve a given concentration, and distributing the resultant mixture to an area or device to be tested is described. The apparatus is comprised of blowers, a holder for the combustion product generating materials (which burn at a predictable and controlled rate), a mixing plenum chamber, and a means for distributing the air combustion product mixture.

Chlorhexidine salt-loaded polyurethane orthodontic chains: in vitro release and antibacterial activity studies.

PubMed

Padois, Karine; Bertholle, Valérie; Pirot, Fabrice; Hyunh, Truc Thanh Ngoc; Rossi, Alessandra; Colombo, Paolo; Falson, Françoise; Sonvico, Fabio

2012-12-01

The widespread use of indwelling medical devices has enormously increased the interest in materials incorporating antibiotics and antimicrobial agents as a means to prevent dangerous device-related infections. Recently, chlorhexidine-loaded polyurethane has been proposed as a material suitable for the production of devices which are able to resist microbial contamination. The aim of the present study was to characterize the in vitro release of chlorhexidine from new polymeric orthodontic chains realized with polyurethane loaded with two different chlorhexidine salts: chlorhexidine diacetate or chlorhexidine digluconate. The orthodontic chains constituted of three layers: a middle polyurethane layer loaded with chlorhexidine salt inserted between two layers of unloaded polymer. In vitro release of chlorhexidine diacetate and digluconate from orthodontic chains loaded with 10% or 20% (w/w) chlorhexidine salt was sustained for 42 days and followed Fickian diffusion. The drug diffusion through the polyurethane was found to be dependent not only on chlorhexidine loading, but also on the type of chlorhexidine salt. The antibacterial activity of 0.2% (w/w) chlorhexidine diacetate-loaded orthodontic chain was successfully tested towards clinically isolated biofilm forming ica-positive Staphylococcus epidermidis via agar diffusion test. In conclusion, the chlorhexidine salt-loaded chains could provide an innovative approach in the prevention of oral infections related to the use of orthodontic devices.

21 CFR 872.3660 - Impression material.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Impression material. 872.3660 Section 872.3660...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3660 Impression material. (a) Identification. Impression material is a device composed of materials such as alginate or polysulfide intended to be placed...

21 CFR 872.3660 - Impression material.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Impression material. 872.3660 Section 872.3660...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3660 Impression material. (a) Identification. Impression material is a device composed of materials such as alginate or polysulfide intended to be placed...

Transit Reconfigurable Exerciser - Intern Exit Abstract

NASA Technical Reports Server (NTRS)

Gebara, Christine A.

2014-01-01

The Transit Resistive Exerciser (TREX) was developed during a 16 week period in which a clutch device filled with smart material was built and began the testing phase. The clutch serves as a passive method of creating resistance. When paired with a series of springs, the device creates a rowing machine also capable of resistive exercise configurations. The device has loading profiles similar to the exercise devices used on the International Space Station today. The prototype created was designed in a modular fashion to support parallel development on various aspects of the project. Hardware and software are currently in development and make use of commercially available parts. Similar technologies have been used in the automotive industry but have never been explored in the context of countermeasure systems for space flight. If the work done leads to successful testing and further development, this technology has the potential to cut the size and weight of exercise devices by an order of magnitude or more.

On-Demand Cell Internal Short Circuit Device

NASA Technical Reports Server (NTRS)

Darcy, Eric; Keyser, Matthew

2014-01-01

A device implantable in Li-ion cells that can generate a hard internal short circuit on-demand by exposing the cell to 60?C has been demonstrated to be valuable for expanding our understanding of cell responses. The device provides a negligible impact to cell performance and enables the instigation of the 4 general categories of cell internal shorts to determine relative severity and cell design susceptibility. Tests with a 18650 cell design indicates that the anode active material short to the aluminum cathode current collector tends to be more catastrophic than the 3 other types of internal shorts. Advanced safety features (such as shutdown separators) to prevent or mitigate the severity of cell internal shorts can be verified with this device. The hard short success rate achieved to date in 18650 cells is about 80%, which is sufficient for using these cells in battery assemblies for field-failure-relevant, cell-cell thermal runaway propagation verification tests

Engineering the switching dynamics of TiOx-based RRAM with Al doping

NASA Astrophysics Data System (ADS)

Trapatseli, Maria; Khiat, Ali; Cortese, Simone; Serb, Alexantrou; Carta, Daniela; Prodromakis, Themistoklis

2016-07-01

Titanium oxide (TiOx) has attracted a lot of attention as an active material for resistive random access memory (RRAM), due to its versatility and variety of possible crystal phases. Although existing RRAM materials have demonstrated impressive characteristics, like ultra-fast switching and high cycling endurance, this technology still encounters challenges like low yields, large variability of switching characteristics, and ultimately device failure. Electroforming has been often considered responsible for introducing irreversible damage to devices, with high switching voltages contributing to device degradation. In this paper, we have employed Al doping for tuning the resistive switching characteristics of titanium oxide RRAM. The resistive switching threshold voltages of undoped and Al-doped TiOx thin films were first assessed by conductive atomic force microscopy. The thin films were then transferred in RRAM devices and tested with voltage pulse sweeping, demonstrating that the Al-doped devices could on average form at lower potentials compared to the undoped ones and could support both analog and binary switching at potentials as low as 0.9 V. This work demonstrates a potential pathway for implementing low-power RRAM systems.

Standards in capstone design courses and the engineering curriculum.

PubMed

Goldberg, Jay

2012-01-01

In 1990, I was the group leader of Research and Development for Surgitek, a urological device manufacturer in Racine, Wisconsin, which was the market leader in ureteral stents. I recognized the need for an industry standard for ureteral stents, felt that taking a leadership role in the development of a new standard would be a good professional development activity, and volunteered to serve as the chair of the American Society for Testing and Materials (ASTM, now known as ASTM International) Task Group on Ureteral Stents. After several years, the standard was approved, and I continue to serve as the chair of the ASTM Subcommittee on Urological Materials and Devices. This experience helped me understand the value of industry standards, expanded my professional network and visibility within the medical device industry, and helped develop my leadership skills.

Testing of New Materials and Computer Aided Optimization of Process Parameters and Clamping Device During Predevelopment of Laser Welding Processes

NASA Astrophysics Data System (ADS)

Weidinger, Peter; Günther, Kay; Fitzel, Martin; Logvinov, Ruslan; Ilin, Alexander; Ploshikhin, Vasily; Hugger, Florian; Mann, Vincent; Roth, Stephan; Schmidt, Michael

The necessity for weight reduction in motor vehicles in order to save fuel consumption pushes automotive suppliers to use materials of higher strength. Due to their excellent crash behavior high strength steels are increasingly applied in various structures. In this paper some predevelopment steps for a material change from a micro alloyed to dual phase and complex phase steels of a T-joint assembly are displayed. Initially the general weldability of the materials regarding pore formation, hardening in the heat affected zone and hot cracking susceptibility is discussed. After this basic investigation, the computer aided design optimization of a clamping device is shown, in which influences of the clamping jaw, the welding position and the clamping forces upon weld quality are presented. Finally experimental results of the welding process are displayed, which validate the numerical simulation.

Development of devices for self-injection: using tribological analysis to optimize injection force

PubMed Central

Lange, Jakob; Urbanek, Leos; Burren, Stefan

2016-01-01

This article describes the use of analytical models and physical measurements to characterize and optimize the tribological behavior of pen injectors for self-administration of biopharmaceuticals. One of the main performance attributes of this kind of device is its efficiency in transmitting the external force applied by the user on to the cartridge inside the pen in order to effectuate an injection. This injection force characteristic is heavily influenced by the frictional properties of the polymeric materials employed in the mechanism. Standard friction tests are available for characterizing candidate materials, but they use geometries and conditions far removed from the actual situation inside a pen injector and thus do not always generate relevant data. A new test procedure, allowing the direct measurement of the coefficient of friction between two key parts of a pen injector mechanism using real parts under simulated use conditions, is presented. In addition to the absolute level of friction, the test method provides information on expected evolution of friction over lifetime as well as on expected consistency between individual devices. Paired with an analytical model of the pen mechanism, the frictional data allow the expected overall injection system force efficiency to be estimated. The test method and analytical model are applied to a range of polymer combinations with different kinds of lubrication. It is found that material combinations used without lubrication generally have unsatisfactory performance, that the use of silicone-based internal lubricating additives improves performance, and that the best results can be achieved with external silicone-based lubricants. Polytetrafluoroethylene-based internal lubrication and external lubrication are also evaluated but found to provide only limited benefits unless used in combination with silicone. PMID:27274319

77 FR 71717 - Federal Motor Vehicle Safety Standards; Lamps, Reflective Devices, and Associated Equipment

Federal Register 2010, 2011, 2012, 2013, 2014

2012-12-04

... that the agency clarify that polymers and additives would not have to be retested to the three year... state that materials and additives used in plastics could be changed without outdoor exposure testing if.... Paragraph S14.4.2.2.2 currently states that materials and additives used in plastics can be changed without...

The development of radioactive sample surrogates for training and exercises

DOE Office of Scientific and Technical Information (OSTI.GOV)

Martha Finck; Bevin Brush; Dick Jansen

2012-03-01

The development of radioactive sample surrogates for training and exercises Source term information is required for to reconstruct a device used in a dispersed radiological dispersal device. Simulating a radioactive environment to train and exercise sampling and sample characterization methods with suitable sample materials is a continued challenge. The Idaho National Laboratory has developed and permitted a Radioactive Response Training Range (RRTR), an 800 acre test range that is approved for open air dispersal of activated KBr, for training first responders in the entry and exit from radioactively contaminated areas, and testing protocols for environmental sampling and field characterization. Membersmore » from the Department of Defense, Law Enforcement, and the Department of Energy participated in the first contamination exercise that was conducted at the RRTR in the July 2011. The range was contaminated using a short lived radioactive Br-82 isotope (activated KBr). Soil samples contaminated with KBr (dispersed as a solution) and glass particles containing activated potassium bromide that emulated dispersed radioactive materials (such as ceramic-based sealed source materials) were collected to assess environmental sampling and characterization techniques. This presentation summarizes the performance of a radioactive materials surrogate for use as a training aide for nuclear forensics.« less

Energy conversion device with support member having pore channels

DOEpatents

Routkevitch, Dmitri [Longmont, CO; Wind, Rikard A [Johnstown, CO

2014-01-07

Energy devices such as energy conversion devices and energy storage devices and methods for the manufacture of such devices. The devices include a support member having an array of pore channels having a small average pore channel diameter and having a pore channel length. Material layers that may include energy conversion materials and conductive materials are coaxially disposed within the pore channels to form material rods having a relatively small cross-section and a relatively long length. By varying the structure of the materials in the pore channels, various energy devices can be fabricated, such as photovoltaic (PV) devices, radiation detectors, capacitors, batteries and the like.

Radiation sensitive devices and systems for detection of radioactive materials and related methods

DOEpatents

Kotter, Dale K

2014-12-02

Radiation sensitive devices include a substrate comprising a radiation sensitive material and a plurality of resonance elements coupled to the substrate. Each resonance element is configured to resonate responsive to non-ionizing incident radiation. Systems for detecting radiation from a special nuclear material include a radiation sensitive device and a sensor located remotely from the radiation sensitive device and configured to measure an output signal from the radiation sensitive device. In such systems, the radiation sensitive device includes a radiation sensitive material and a plurality of resonance elements positioned on the radiation sensitive material. Methods for detecting a presence of a special nuclear material include positioning a radiation sensitive device in a location where special nuclear materials are to be detected and remotely interrogating the radiation sensitive device with a sensor.

Materials for electrochemical device safety

DOEpatents

Vissers, Daniel R.; Amine, Khalil; Thackeray, Michael M.; Kahaian, Arthur J.; Johnson, Christopher S.

2015-04-07

An electrochemical device includes a thermally-triggered intumescent material or a gas-triggered intumescent material. Such devices prevent or minimize short circuits in a device that could lead to thermal run-away. Such devices may include batteries or supercapacitors.

Bending strength measurements at different materials used for IR-cut filters in mobile camera devices

NASA Astrophysics Data System (ADS)

Dietrich, Volker; Hartmann, Peter; Kerz, Franca

2015-03-01

Digital cameras are present everywhere in our daily life. Science, business or private life cannot be imagined without digital images. The quality of an image is often rated by its color rendering. In order to obtain a correct color recognition, a near infrared cut (IRC-) filter must be used to alter the sensitivity of imaging sensor. Increasing requirements related to color balance and larger angle of incidence (AOI) enforced the use of new materials as the e.g. BG6X series which substitutes interference coated filters on D263 thin glass. Although the optical properties are the major design criteria, devices have to withstand numerous environmental conditions during use and manufacturing - as e.g. temperature change, humidity, and mechanical shock, as wells as mechanical stress. The new materials show different behavior with respect to all these aspects. They are usually more sensitive against these requirements to a larger or smaller extent. Mechanical strength is especially different. Reliable strength data are of major interest for mobile phone camera applications. As bending strength of a glass component depends not only upon the material itself, but mainly on the surface treatment and test conditions, a single number for the strength might be misleading if the conditions of the test and the samples are not described precisely,. Therefore, Schott started investigations upon the bending strength data of various IRC-filter materials. Different test methods were used to obtain statistical relevant data.

New developments in CVD diamond for detector applications

NASA Astrophysics Data System (ADS)

Adam, W.; Berdermann, E.; Bergonzo, P.; de Boer, W.; Bogani, F.; Borchi, E.; Brambilla, A.; Bruzzi, M.; Colledani, C.; Conway, J.; D'Angelo, P.; Dabrowski, W.; Delpierre, P.; Dulinski, W.; Doroshenko, J.; van Eijk, B.; Fallou, A.; Fischer, P.; Fizzotti, F.; Furetta, C.; Gan, K. K.; Ghodbane, N.; Grigoriev, E.; Hallewell, G.; Han, S.; Hartjes, F.; Hrubec, J.; Husson, D.; Kagan, H.; Kaplon, J.; Kass, R.; Keil, M.; Knoepfle, K. T.; Koeth, T.; Krammer, M.; Logiudice, A.; Lu, R.; Mac Lynne, L.; Manfredotti, C.; Meier, D.; Menichelli, D.; Meuser, S.; Mishina, M.; Moroni, L.; Noomen, J.; Oh, A.; Pernicka, M.; Perera, L.; Potenza, R.; Riester, J. L.; Roe, S.; Rudge, A.; Sala, S.; Sampietro, M.; Schnetzer, S.; Sciortino, S.; Stelzer, H.; Stone, R.; Sutera, C.; Trischuk, W.; Tromson, D.; Tuve, C.; Vincenzo, B.; Weilhammer, P.; Wermes, N.; Wetstein, M.; Zeuner, W.; Zoeller, M.

Chemical Vapor Deposition (CVD) diamond has been discussed extensively as an alternative sensor material for use very close to the interaction region of the LHC and other machines where extreme radiation conditions exist. During the last seven years the RD42 collaboration has developed diamond detectors and tested them with LHC electronics towards the end of creating a device usable by experiments. The most recent results of this work are presented. Recently, a new form of CVD diamond has been developed: single crystal CVD diamond which resolves many of the issues associated with poly-crystalline CVD material. The first tests of this material are also presented.

Micro-optical elements produced using an photo-embossing technique in photopolymers

NASA Astrophysics Data System (ADS)

O'Neill, Feidhlim T.; Rowsome, Ita C.; Carr, Alun J.; Daniels, Stephen M.; Gleeson, Michael R.; Kelly, John V.; Close, Ciara; Lawrence, Justin R.; Sheridan, John T.

2005-09-01

Micro-optical devices are very important in current high-tech consumer items. The development of future products depends on both the evolution of fabrication techniques and on the development of new low cost mass production methods. Polymers offer ease of fabrication and low cost and are therefore excellent materials for the development of micro-optical devices. Polymer optical devices include passive optical elements, such as microlens arrays and waveguides, as well as active devices such as polymer based lasers. One of the most important areas of micro-optics is that of microlens design, manufacture and testing. The wide diversity of fabrication methods used for the production of these elements indicates their importance. One of these fabrication techniques is photo-embossing. The use of the photo-embossing technique and a photopolymer holographic recording material will be examined in this paper. A discussion of current attempts to model the fabrication process and a review of the experimental method will be given.

Methods of measurement for semiconductor materials, process control, and devices

NASA Technical Reports Server (NTRS)

Bullis, W. M. (Editor)

1973-01-01

This progress report describes NBS activities directed toward the development of methods of measurement for semiconductor materials, process control, and devices. Significant accomplishments during this reporting period include design of a plan to provide standard silicon wafers for four-probe resistivity measurements for the industry, publication of a summary report on the photoconductive decay method for measuring carrier lifetime, publication of a comprehensive review of the field of wire bond fabrication and testing, and successful completion of organizational activity leading to the establishment of a new group on quality and hardness assurance in ASTM Committee F-1 on Electronics. Work is continuing on measurement of resistivity of semiconductor crystals; characterization of generation-recombination-trapping centers in silicon; study of gold-doped silicon; development of the infrared response technique; evaluation of wire bonds and die attachment; and measurement of thermal properties of semiconductor devices, delay time and related carrier transport properties in junction devices, and noise properties of microwave diodes.

Shuttle filter study. Volume 2: Contaminant generation and sensitivity studies

NASA Technical Reports Server (NTRS)

1974-01-01

Contaminant generation studies were conducted at the component level using two different methods, radioactive tracer technique and gravimetric analysis test procedure. Both of these were reduced to practice during this program. In the first of these methods, radioactively tagged components typical of those used in spacecraft were studied to determine their contaminant generation characteristics under simulated operating conditions. Because the purpose of the work was: (1) to determine the types and quantities of contaminants generated; and (2) to evaluate improved monitoring and detection schemes, no attempt was made to evaluate or qualify specific components. The components used in this test program were therefore not flight hardware items. Some of them had been used in previous tests; some were obsolete; one was an experimental device. In addition to the component tests, various materials of interest to contaminant and filtration studies were irradiated and evaluated for use as autotracer materials. These included test dusts, plastics, valve seat materials, and bearing cage materials.

Deformable image registration with content mismatch: a demons variant to account for added material and surgical devices in the target image

NASA Astrophysics Data System (ADS)

Nithiananthan, S.; Uneri, A.; Schafer, S.; Mirota, D.; Otake, Y.; Stayman, J. W.; Zbijewski, W.; Khanna, A. J.; Reh, D. D.; Gallia, G. L.; Siewerdsen, J. H.

2013-03-01

Fast, accurate, deformable image registration is an important aspect of image-guided interventions. Among the factors that can confound registration is the presence of additional material in the intraoperative image - e.g., contrast bolus or a surgical implant - that was not present in the prior image. Existing deformable registration methods generally fail to account for tissue excised between image acquisitions and typically simply "move" voxels within the images with no ability to account for tissue that is removed or introduced between scans. We present a variant of the Demons algorithm to accommodate such content mismatch. The approach combines segmentation of mismatched content with deformable registration featuring an extra pseudo-spatial dimension representing a reservoir from which material can be drawn into the registered image. Previous work tested the registration method in the presence of tissue excision ("missing tissue"). The current paper tests the method in the presence of additional material in the target image and presents a general method by which either missing or additional material can be accommodated. The method was tested in phantom studies, simulations, and cadaver models in the context of intraoperative cone-beam CT with three examples of content mismatch: a variable-diameter bolus (contrast injection); surgical device (rod), and additional material (bone cement). Registration accuracy was assessed in terms of difference images and normalized cross correlation (NCC). We identify the difficulties that traditional registration algorithms encounter when faced with content mismatch and evaluate the ability of the proposed method to overcome these challenges.

Liquid salt environment stress-rupture testing

DOEpatents

Ren, Weiju; Holcomb, David E.; Muralidharan, Govindarajan; Wilson, Dane F.

2016-03-22

Disclosed herein are systems, devices and methods for stress-rupture testing selected materials within a high-temperature liquid salt environment. Exemplary testing systems include a load train for holding a test specimen within a heated inert gas vessel. A thermal break included in the load train can thermally insulate a load cell positioned along the load train within the inert gas vessel. The test specimen can include a cylindrical gage portion having an internal void filled with a molten salt during stress-rupture testing. The gage portion can have an inner surface area to volume ratio of greater than 20 to maximize the corrosive effect of the molten salt on the specimen material during testing. Also disclosed are methods of making a salt ingot for placement within the test specimen.

Effect of ELMs on deuterium-loaded-tungsten plasma facing components

NASA Astrophysics Data System (ADS)

Umstadter, K. R.; Rudakov, D. L.; Wampler, W.; Watkins, J. G.; Wong, C. P. C.

2011-08-01

Prior heat pulse testing of plasma facing components (PFCs) has been completed in vacuum environments without the presence of background plasma. Edge localized modes (ELMs) will not be this kind of isolated event and one should know the effect of a plasma background during these transients. Heat-pulse experiments have been conducted in the PISCES-A device utilizing laser heating in a divertor-like plasma background. Initial results indicate that the erosion of PFCs is enhanced as compared to heat pulse or plasma only tests. To determine if the enhanced erosion effect is a phenomena only witnessed in the laboratory PISCES device, tungsten and graphite samples were exposed to plasmas in the lower divertor of the DIII-D tokamak using the Divertor Material Evaluation System (DiMES). Mass loss analysis indicates that materials that contain significant deuterium prior to experiencing a transient heating event will erode faster than those that have no or little retained deuterium.

Manufacturing of embedded multimode waveguides by reactive lamination of cyclic olefin polymer and polymethylmethacrylate

NASA Astrophysics Data System (ADS)

Kelb, Christian; Rother, Raimund; Schuler, Anne-Katrin; Hinkelmann, Moritz; Rahlves, Maik; Prucker, Oswald; Müller, Claas; Rühe, Jürgen; Reithmeier, Eduard; Roth, Bernhard

2016-03-01

We demonstrate the manufacturing of embedded multimode optical waveguides through linking of polymethylmethacrylate (PMMA) foils and cyclic olefin polymer (COP) filaments based on a lamination process. Since the two polymeric materials cannot be fused together through interdiffusion of polymer chains, we utilize a reactive lamination agent based on PMMA copolymers containing photoreactive 2-acryloyloxyanthraquinone units, which allows the creation of monolithic PMMA-COP substrates through C-H insertion reactions across the interface between the two materials. We elucidate the lamination process and evaluate the chemical link between filament and foils by carrying out extraction tests with a custom-built tensile testing machine. We also show attenuation measurements of the manufactured waveguides for different manufacturing parameters. The lamination process is in particular suited for large-scale and low-cost fabrication of board-level devices with optical waveguides or other micro-optical structures, e.g., optofluidic devices.

An Anisotropic Model for Magnetostriction and Magnetization Computing for Noise Generation in Electric Devices.

PubMed

Mbengue, Serigne Saliou; Buiron, Nicolas; Lanfranchi, Vincent

2016-04-16

During the manufacturing process and use of ferromagnetic sheets, operations such as rolling, cutting, and tightening induce anisotropy that changes the material's behavior. Consequently for more accuracy in magnetization and magnetostriction calculations in electric devices such as transformers, anisotropic effects should be considered. In the following sections, we give an overview of a macroscopic model which takes into account the magnetic and magnetoelastic anisotropy of the material for both magnetization and magnetostriction computing. Firstly, a comparison between the model results and measurements from a Single Sheet Tester (SST) and values will be shown. Secondly, the model is integrated in a finite elements code to predict magnetostrictive deformation of an in-house test bench which is a stack of 40 sheets glued together by the Vacuum-Pressure Impregnation (VPI) method. Measurements on the test bench and Finite Elements results are presented.

A low-ignition energy, SCB, thermite igniter

DOE Office of Scientific and Technical Information (OSTI.GOV)

Bickes, R.W. Jr.; Grubelich, M.C.; Wackerbarth, D.E.

1996-06-01

The authors describe threshold ignition studies for semiconductor bridge, SCB, ignition of aluminum/copper oxide (Al/CuO) thermite as a function of the capacitor discharge unit (CDU) firing set discharge capacitance, the charge holder material and the morphology of the CuO. All of the tests were carried out with the devices cooled to 0 F ({minus}18 C). They compared ignition thresholds using a brass charge holder and a G10 charge holder; G10 is a non-conducting, fiber-glass-epoxy composite material. They determined that at 50 V on the discharge capacitor, the thresholds were 30.1 {micro}F and 2.0 {micro}F respectively. The tests revealed that differentmore » CuO morphologies affected the function time (interval between start of the firing set current and the output of the thermite device) but did not significantly affect the threshold sensitivity.« less

KENNEDY SPACE CENTER, FLA. - Louis MacDowell (right), Testbed manager, explains to Center Director Jim Kennedy the use of astmospheric calibration specimens. Placed at various locations, they can rank the corrosivity of the given environment. The KSC Beach Corrosion Test Site was established in the 1960s and has provided more than 30 years of historical information on the long-term performance of many materials in use at KSC and other locations around the world. Located 100 feet from the Atlantic Ocean approximately 1 mile south of the Space Shuttle launch sites, the test facility includes an atmospheric exposure site, a flowing seawater exposure site, and an on-site electrochemistry laboratory and monitoring station. The beach laboratory is used to conduct real-time corrosion experiments and provides for the remote monitoring of surrounding weather conditions. The newly added flowing seawater immersion facility provides for the immersion testing of materials and devices under controlled conditions.

NASA Image and Video Library

2003-08-21

KENNEDY SPACE CENTER, FLA. - Louis MacDowell (right), Testbed manager, explains to Center Director Jim Kennedy the use of astmospheric calibration specimens. Placed at various locations, they can rank the corrosivity of the given environment. The KSC Beach Corrosion Test Site was established in the 1960s and has provided more than 30 years of historical information on the long-term performance of many materials in use at KSC and other locations around the world. Located 100 feet from the Atlantic Ocean approximately 1 mile south of the Space Shuttle launch sites, the test facility includes an atmospheric exposure site, a flowing seawater exposure site, and an on-site electrochemistry laboratory and monitoring station. The beach laboratory is used to conduct real-time corrosion experiments and provides for the remote monitoring of surrounding weather conditions. The newly added flowing seawater immersion facility provides for the immersion testing of materials and devices under controlled conditions.

Field Demonstration and Validation of a New Device for Measuring Water and Solute Fluxes at CFB Borden

DTIC Science & Technology

2006-11-01

All Quality Control Reference Materials are acquired only from authorized vendors or sources commonly used by U.S. EPA Regional Laboratories...Institue of Standards and Testing (NITS) Standard Reference Materials (SRM) or to the U.S. EPA Reference Standards. Working Standards The commercial...contaminants from clothing or equipment by blowing, shaking or any other means that may disperse material into the air is prohibited. 7.1.3. All disposable

Interactive Physics and Characteristics of Photons and Photoelectrons in Hyperbranched Zinc Oxide Nanostructures

NASA Astrophysics Data System (ADS)

Torix, Garrett

As is commonly known, the world is full of technological wonders, where a multitude of electronic devices and instruments continuously help push the boundaries of scientific knowledge and discovery. These new devices and instruments of science must be utilized at peak efficiency in order to benefit humanity with the most advanced scientific knowledge. In order to attain this level of efficiency, the materials which make up these electronics, or possibly more important, the fundamental characteristics of these materials, must be fully understood. The following research attempted to uncover the properties and characteristics of a selected family of materials. Herein, zinc oxide (ZnO) nanomaterials were investigated and subjected to various, systematical tests, with the aim of discovering new and useful properties. The various nanostructures were grown on a quartz substrate, between a pair of gold electrodes, and subjected to an electrical bias which produced a measurable photocurrent under sufficient lighting conditions. This design formed a novel photodetector device, which, when combined with a simple solar cell and a methodical set of experimental trials, allowed several unique phenomena to be studied. Under various conditions, the device photocurrent as a function of applied voltage, as well as transmitted light, were measured and compared between devices of different ZnO morphologies. Zinc oxide is an absorber of ultraviolet (UV) light. UV absorbing materials and devices have uses in solar cells, long range communications, and astronomical observational equipment, hence, a better understanding of zinc oxide nanostructures and their properties can lead to more efficient utilization of UV light, improved solar cell technology, and a better understanding of the basic science in photon-to-electricity conversion.

Facilities to Support Beamed Energy Launch Testing at the Laser Hardened Materials Evaluation Laboratory (LHMEL)

NASA Astrophysics Data System (ADS)

Lander, Michael L.

2003-05-01

The Laser Hardened Materials Evaluation Laboratory (LHMEL) has been characterizing material responses to laser energy in support of national defense programs and the aerospace industry for the past 26 years. This paper reviews the overall resources available at LHMEL to support fundamental materials testing relating to impulse coupling measurement and to explore beamed energy launch concepts. Located at Wright-Patterson Air Force Base, Ohio, LHMEL is managed by the Air Force Research Laboratory Materials Directorate AFRL/MLPJ and operated by Anteon Corporation. The facility's advanced hardware is centered around carbon dioxide lasers producing output power up to 135kW and neodymium glass lasers producing up to 10 kilojoules of repetitively pulsed output. The specific capabilities of each laser device and related optical systems are discussed. Materials testing capabilities coupled with the laser systems are also described including laser output and test specimen response diagnostics. Environmental simulation capabilities including wind tunnels and large-volume vacuum chambers relevant to beamed energy propulsion are also discussed. This paper concludes with a summary of the procedures and methods by which the facility can be accessed.

Plasma source development for fusion-relevant material testing

DOE PAGES

Caughman, John B. O.; Goulding, Richard H.; Biewer, Theodore M.; ...

2017-05-01

Plasma facing materials in the divertor of a magnetic fusion reactor will have to tolerate steady-state plasma heat fluxes in the range of 10 MW/m2 for ~107 sec, in addition to fusion neutron fluences, which can damage the plasma facing materials to high displacements per atom (dpa) of ~50 dpa . Material solutions needed for the plasma facing components are yet to be developed and tested. The Materials Plasma Exposure eXperiment (MPEX) is a newly proposed steady state linear plasma device that is designed to deliver the necessary plasma heat flux to a target for this material testing, including themore » capability to expose a-priori neutron damaged material samples to those plasmas. The requirements of the plasma source needed to deliver this plasma heat flux are being developed on the Proto-MPEX device, which is a linear high-intensity radio frequency (RF) plasma source that combines a high-density helicon plasma generator with electron and ion heating sections. It is being used to study the physics of heating over-dense plasmas in a linear configuration. The helicon plasma is operated at 13.56 MHz with RF power levels up to 120 kW. Microwaves at 28 GHz (~30 kW) are coupled to the electrons in the over-dense helicon plasma via Electron Bernstein Waves (EBW), and ion cyclotron heating at 7-9 MHz (~30 kW) is via a magnetic beach approach. High plasma densities >6x1019/m3 have been produced in deuterium, with electron temperatures that can range from 2 to >10 eV. Operation with on-axis magnetic field strengths between 0.6 and 1.4 T is typical. The plasma heat flux delivered to a target can be > 10 MW/m2, depending on the operating conditions.« less

Plasma source development for fusion-relevant material testing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Caughman, John B. O.; Goulding, Richard H.; Biewer, Theodore M.

Plasma facing materials in the divertor of a magnetic fusion reactor will have to tolerate steady-state plasma heat fluxes in the range of 10 MW/m2 for ~107 sec, in addition to fusion neutron fluences, which can damage the plasma facing materials to high displacements per atom (dpa) of ~50 dpa . Material solutions needed for the plasma facing components are yet to be developed and tested. The Materials Plasma Exposure eXperiment (MPEX) is a newly proposed steady state linear plasma device that is designed to deliver the necessary plasma heat flux to a target for this material testing, including themore » capability to expose a-priori neutron damaged material samples to those plasmas. The requirements of the plasma source needed to deliver this plasma heat flux are being developed on the Proto-MPEX device, which is a linear high-intensity radio frequency (RF) plasma source that combines a high-density helicon plasma generator with electron and ion heating sections. It is being used to study the physics of heating over-dense plasmas in a linear configuration. The helicon plasma is operated at 13.56 MHz with RF power levels up to 120 kW. Microwaves at 28 GHz (~30 kW) are coupled to the electrons in the over-dense helicon plasma via Electron Bernstein Waves (EBW), and ion cyclotron heating at 7-9 MHz (~30 kW) is via a magnetic beach approach. High plasma densities >6x1019/m3 have been produced in deuterium, with electron temperatures that can range from 2 to >10 eV. Operation with on-axis magnetic field strengths between 0.6 and 1.4 T is typical. The plasma heat flux delivered to a target can be > 10 MW/m2, depending on the operating conditions.« less

Passive thermal management using phase change materials

NASA Astrophysics Data System (ADS)

Ganatra, Yash Yogesh

The trend of enhanced functionality and reducing thickness of mobile devices has. led to a rapid increase in power density and a potential thermal bottleneck since. thermal limits of components remain unchanged. Active cooling mechanisms are not. feasible due to size, weight and cost constraints. This work explores the feasibility. of a passive cooling system based on Phase Change Materials (PCMs) for thermal. management of mobile devices. PCMs stabilize temperatures due to the latent heat. of phase change thus increasing the operating time of the device before threshold. temperatures are exceeded. The primary contribution of this work is the identification. of key parameters which influence the design of a PCM based thermal management. system from both the experiments and the numerical models. This work first identifies strategies for integrating PCMs in an electronic device. A. detailed review of past research, including experimental techniques and computational. models, yields key material properties and metrics to evaluate the performance of. PCMs. Subsequently, a miniaturized version of a conventional thermal conductivity. measurement technique is developed to characterize thermal resistance of PCMs. Further, latent heat and transition temperatures are also characterized for a wide. range of PCMs. In-situ measurements with PCMs placed on the processor indicate that some. PCMs can extend the operating time of the device by as much as a factor of 2.48. relative to baseline tests (with no PCMs). This increase in operating time is investigated. by computational thermal models that explore various integration locations, both at the package and device level.

Installation and Characterization of Charged Particle Sources for Space Environmental Effects Testing

NASA Technical Reports Server (NTRS)

Skevington, Jennifer L.

2010-01-01

Charged particle sources are integral devices used by Marshall Space Flight Center s Environmental Effects Branch (EM50) in order to simulate space environments for accurate testing of materials and systems. By using these sources inside custom vacuum systems, materials can be tested to determine charging and discharging properties as well as resistance to sputter damage. This knowledge can enable scientists and engineers to choose proper materials that will not fail in harsh space environments. This paper combines the steps utilized to build a low energy electron gun (The "Skevington 3000") as well as the methods used to characterize the output of both the Skevington 3000 and a manufactured Xenon ion source. Such characterizations include beam flux, beam uniformity, and beam energy. Both sources were deemed suitable for simulating environments in future testing.

Helicon plasma ion temperature measurements and observed ion cyclotron heating in proto-MPEX

NASA Astrophysics Data System (ADS)

Beers, C. J.; Goulding, R. H.; Isler, R. C.; Martin, E. H.; Biewer, T. M.; Caneses, J. F.; Caughman, J. B. O.; Kafle, N.; Rapp, J.

2018-01-01

The Prototype-Material Plasma Exposure eXperiment (Proto-MPEX) linear plasma device is a test bed for exploring and developing plasma source concepts to be employed in the future steady-state linear device Material Plasma Exposure eXperiment (MPEX) that will study plasma-material interactions for the nuclear fusion program. The concept foresees using a helicon plasma source supplemented with electron and ion heating systems to reach necessary plasma conditions. In this paper, we discuss ion temperature measurements obtained from Doppler broadening of spectral lines from argon ion test particles. Plasmas produced with helicon heating alone have average ion temperatures downstream of the Helicon antenna in the range of 3 ± 1 eV; ion temperature increases to 10 ± 3 eV are observed with the addition of ion cyclotron heating (ICH). The temperatures are higher at the edge than the center of the plasma either with or without ICH. This type of profile is observed with electrons as well. A one-dimensional RF antenna model is used to show where heating of the plasma is expected.

Material growth and characterization directed toward improving III-V heterojunction solar cells

NASA Technical Reports Server (NTRS)

Stefanakos, E. K.; Alexander, W. E.; Collis, W.; Abul-Fadl, A.

1979-01-01

In addition to the existing materials growth laboratory, the photolithographic facility and the device testing facility were completed. The majority of equipment for data acquisition, solar cell testing, materials growth and device characterization were received and are being put into operation. In the research part of the program, GaAs and GaA1As layers were grown reproducibly on GaAs substrates. These grown layers were characterized as to surface morphology, thickness and thickness uniformity. The liquid phase epitaxial growth process was used to fabricate p-n junctions in Ga(1-x)A1(x)As. Sequential deposition of two alloy layers was accomplished and detailed analysis of the effect of substrate quality and dopant on the GaA1As layer quality is presented. Finally, solar cell structures were formed by growing a thin p-GaA1As layer upon an epitaxial n-GaA1As layer. The energy gap corresponding to the long wavelength cutoff of the spectral response characteristic was 1.51-1.63 eV. Theoretical calculations of the spectral response were matched to the measured response.

Theoretical and material studies on thin-film electroluminescent devices

NASA Technical Reports Server (NTRS)

Summers, C. J.; Brennan, K. F.

1986-01-01

Electroluminescent materials and device technology were assessed. The evaluation strongly suggests the need for a comprehensive theoretical and experimental study of both materials and device structures, particularly in the following areas: carrier generation and multiplication; radiative and nonradiative processes of luminescent centers; device modeling; new device concepts; and single crystal materials growth and characterization. Modeling of transport properties of hot electrons in ZnSe and the generation of device concepts were initiated.

Design, fabrication, and characterization of 4H-silicon carbide rectifiers for power switching applications

NASA Astrophysics Data System (ADS)

Sheridan, David Charles

Silicon Carbide has received a substantial increase in research interest over the past few years as a base material system for high-frequency and high-power semiconductor devices. Of the over 1200 polytypes, 4H-SiC is the most attractive polytype for power devices due to its wide band gap (3.2eV), excellent thermal conductivity (4.9 W/cm·K), and high critical field strength (˜2 x 106 V/cm). Important for power devices, the 10x increase in critical field strength of SiC allows high voltage blocking layers to be fabricated significantly thinner than for comparable Si devices. For power rectifiers, this reduces device on-resistance, while maintaining the same high voltage blocking capability. In this work, 4H-SiC Schottky, pn, and junction barrier Schottky (JBS) rectifiers for use in high voltage switching applications have been designed, fabricated, and extensively characterized. First, a detailed review of 4H-SiC material parameters was performed and SiC models were implemented into a standard Si drift-diffusion numerical simulator. Using these models, a SiC simulation methodology was developed in order to enable predictive SiC device design. A wide variety of rectifier and edge termination designs were investigated and optimized with respect to breakdown efficiency, area consumption, resistance to interface charge, and fabrication practicality. Simulated termination methods include: field plates, floating guard rings, and a variety of junction termination extensions (JTE). Using the device simulation results, both Schottky and JBS rectifiers were fabricated with a novel self-aligned edge termination design, and fabricated with process elements developed at the Alabama Microelectronics Science and Technology Center facility. These rectifiers exhibited near-ideal forward characteristics and had blocking voltages in excess of 2.5kV. The SiC diodes were subjected to inductive switching tests, and were found to have superior reverse recovery characteristics compared to a similar Si diode. Finally, the performance of these SiC rectifiers were tested in inductive switching circuits and in high dose gamma radiation environments. In both cases, these devices were shown to be superior to their silicon counterparts. The details of this work was presented and published in the proceedings of the 45th International Meeting of the American Vacuum Society [1], the 1999 International Conference on Silicon Carbide and Related Materials [2, 3] and the 2000 European Conference on Silicon Carbide and Related Materials [4]. The expanded conference papers were published in the international journal. Solid-State Electronics [5, 6].

A Novel Solid State Ultracapacitor

NASA Technical Reports Server (NTRS)

Cortes-Pena, A. Y.; Rolin, T. D.; Hill, C. W.

2017-01-01

Novel dielectric materials were researched to develop an internal barrier layer capacitor that is fully solid state. These materials included reduced nanoparticles of barium titanate that were coated with various atomic layer deposited oxides. The nanoparticle powders were then densified into pellets and characterized using a dielectric test fixture over a frequency range of 20 Hz to 2 MHz. Densification and sintering were evaluated using scanning electron microscopic techniques. Ultimately, the samples showing the most promising electrical characteristics of permittivity, dissipation factor and equivalent series resistance were chosen to manufacture devices for subsequent testing.

46 CFR 160.060-7 - Inspections and tests-standard and nonstandard vests. 1

Code of Federal Regulations, 2010 CFR

2010-10-01

... 46 Shipping 6 2010-10-01 2010-10-01 false Inspections and tests-standard and nonstandard vests. 1... and nonstandard vests. 1 1 The manufacturer of a personal flotation device must meet 33 CFR 181.701... shall— (1) Maintain quality control of the materials used, the manufacturing methods, and the finished...

46 CFR 160.060-7 - Inspections and tests-standard and nonstandard vests. 1

Code of Federal Regulations, 2011 CFR

2011-10-01

... 46 Shipping 6 2011-10-01 2011-10-01 false Inspections and tests-standard and nonstandard vests. 1... and nonstandard vests. 1 1 The manufacturer of a personal flotation device must meet 33 CFR 181.701... shall— (1) Maintain quality control of the materials used, the manufacturing methods, and the finished...

A novel three-dimensional printed guiding device for electrode implantation of sacral neuromodulation.

PubMed

Cui, Z; Wang, Z; Ye, G; Zhang, C; Wu, G; Lv, J

2018-01-01

The aim was to test the feasibility of a novel three-dimensional (3D) printed guiding device for electrode implantation of sacral neuromodulation (SNM). A 3D printed guiding device for electrode implantation was customized to patients' anatomy of the sacral region. Liquid photopolymer was selected as the printing material. The details of the device designation and prototype building are described. The guiding device was used in two patients who underwent SNM for intractable constipation. Details of the procedure and the outcomes are given. With the help of the device, the test needle for stimulation was placed in the target sacral foramen successfully at the first attempt of puncture in both patients. The time to implant a tined SNM electrode was less than 20 min and no complications were observed. At the end of the screening phase, symptoms of constipation were relieved by more than 50% in both patients and permanent stimulation was established. The customized 3D printed guiding device for implantation of SNM is a promising instrument that facilitates a precise and quick implantation of the electrode into the target sacral foramen. Colorectal Disease © 2017 The Association of Coloproctology of Great Britain and Ireland.

Functionalized graphene and other two-dimensional materials for photovoltaic devices: device design and processing.

PubMed

Liu, Zhike; Lau, Shu Ping; Yan, Feng

2015-08-07

Graphene is the thinnest two-dimensional (2D) carbon material and has many advantages including high carrier mobilities and conductivity, high optical transparency, excellent mechanical flexibility and chemical stability, which make graphene an ideal material for various optoelectronic devices. The major applications of graphene in photovoltaic devices are for transparent electrodes and charge transport layers. Several other 2D materials have also shown advantages in charge transport and light absorption over traditional semiconductor materials used in photovoltaic devices. Great achievements in the applications of 2D materials in photovoltaic devices have been reported, yet numerous challenges still remain. For practical applications, the device performance should be further improved by optimizing the 2D material synthesis, film transfer, surface functionalization and chemical/physical doping processes. In this review, we will focus on the recent advances in the applications of graphene and other 2D materials in various photovoltaic devices, including organic solar cells, Schottky junction solar cells, dye-sensitized solar cells, quantum dot-sensitized solar cells, other inorganic solar cells, and perovskite solar cells, in terms of the functionalization techniques of the materials, the device design and the device performance. Finally, conclusions and an outlook for the future development of this field will be addressed.

Device for Automated Cutting and Transfer of Plant Shoots

NASA Technical Reports Server (NTRS)

Cipra, Raymond; Das, Hari; Ali, Khaled; Hong, Dennis

2003-01-01

A device that enables the automated cutting and transfer of plant shoots is undergoing development for use in the propagation of plants in a nursery or laboratory. At present, it is standard practice for a human technician to use a knife and forceps to cut, separate, and grasp a plant shoot. The great advantage offered by the present device is that its design and operation are simpler than would be those of a device based on the manual cutting/separation/grasping procedure. [The present device should not be confused with a prior device developed for partly the same purpose and described in Compliant Gripper for a Robotic Manipulator (NPO-21104), NASA Tech Briefs, Vol. 27, No. 3 (March 2003), page 59.]. The device (see figure) includes a circular tube sharpened at its open (lower) end and mounted on a robotic manipulator at its closed (upper) end. The robotic manipulator simply pushes the sharpened open end of the tube down onto a bed of plants and rotates a few degrees clockwise then counterclockwise about the vertical axis, causing the tube to cut a cylindrical plug of plant material. Exploiting the natural friction between the tube and plug, the tube retains the plug, without need for a gripping mechanism and control. The robotic manipulator then retracts the tube, translates it to a new location over a plant-growth tray, and inserts the tube part way into the growth medium at this location in the tray. A short burst of compressed air is admitted to the upper end of the tube to eject the plug of plant material and drive it into the growth medium. A prototype has been tested and verified to function substantially as intended. It is projected that in the fully developed robotic plant-propagation system, the robot control system would include a machine- vision subsystem that would automatically guide the robotic manipulator in choosing the positions from which to cut plugs of plant material. Planned further development efforts also include more testing and refinement of the design and operation described above.

Early Career. Harnessing nanotechnology for fusion plasma-material interface research in an in-situ particle-surface interaction facility

DOE Office of Scientific and Technical Information (OSTI.GOV)

Allain, Jean Paul

2014-08-08

This project consisted of fundamental and applied research of advanced in-situ particle-beam interactions with surfaces/interfaces to discover novel materials able to tolerate intense conditions at the plasma-material interface (PMI) in future fusion burning plasma devices. The project established a novel facility that is capable of not only characterizing new fusion nanomaterials but, more importantly probing and manipulating materials at the nanoscale while performing subsequent single-effect in-situ testing of their performance under simulated environments in fusion PMI.

Biological materials: a materials science approach.

PubMed

Meyers, Marc A; Chen, Po-Yu; Lopez, Maria I; Seki, Yasuaki; Lin, Albert Y M

2011-07-01

The approach used by Materials Science and Engineering is revealing new aspects in the structure and properties of biological materials. The integration of advanced characterization, mechanical testing, and modeling methods can rationalize heretofore unexplained aspects of these structures. As an illustration of the power of this methodology, we apply it to biomineralized shells, avian beaks and feathers, and fish scales. We also present a few selected bioinspired applications: Velcro, an Al2O3-PMMA composite inspired by the abalone shell, and synthetic attachment devices inspired by gecko. Copyright © 2010 Elsevier Ltd. All rights reserved.

A mechanical system for tensile testing of supported films at the nanoscale.

PubMed

Pantano, Maria F; Speranza, G; Galiotis, Costas; Pugno, Nicola M

2018-06-27

Standard tensile tests of materials are usually performed on freestanding specimens. However, such requirement is difficult to implement when the materials of interest are of nanoscopic dimensions due to problems related to their handling and manipulation. In the present paper, a new device is presented for tensile testing of thin nanomaterials, which allows tests to be carried out on specimens initially deposited onto a macroscopic pre-notched substrate. On loading, however, no substrate effects are introduced, allowing the films to be freely stretched. The results obtained from a variety of thin metal or polymeric films are very promising for the further development of this technique as a standard method for nanomaterial mechanical testing. © 2018 IOP Publishing Ltd.

Non-Destructive Techniques Based on Eddy Current Testing

PubMed Central

García-Martín, Javier; Gómez-Gil, Jaime; Vázquez-Sánchez, Ernesto

2011-01-01

Non-destructive techniques are used widely in the metal industry in order to control the quality of materials. Eddy current testing is one of the most extensively used non-destructive techniques for inspecting electrically conductive materials at very high speeds that does not require any contact between the test piece and the sensor. This paper includes an overview of the fundamentals and main variables of eddy current testing. It also describes the state-of-the-art sensors and modern techniques such as multi-frequency and pulsed systems. Recent advances in complex models towards solving crack-sensor interaction, developments in instrumentation due to advances in electronic devices, and the evolution of data processing suggest that eddy current testing systems will be increasingly used in the future. PMID:22163754

Non-destructive techniques based on eddy current testing.

PubMed

García-Martín, Javier; Gómez-Gil, Jaime; Vázquez-Sánchez, Ernesto

2011-01-01

Non-destructive techniques are used widely in the metal industry in order to control the quality of materials. Eddy current testing is one of the most extensively used non-destructive techniques for inspecting electrically conductive materials at very high speeds that does not require any contact between the test piece and the sensor. This paper includes an overview of the fundamentals and main variables of eddy current testing. It also describes the state-of-the-art sensors and modern techniques such as multi-frequency and pulsed systems. Recent advances in complex models towards solving crack-sensor interaction, developments in instrumentation due to advances in electronic devices, and the evolution of data processing suggest that eddy current testing systems will be increasingly used in the future.

Enhanced affordable methods for assessment of material characteristics and consolidation effects on stone and mortar

NASA Astrophysics Data System (ADS)

Drdacky, M.; Slizkova, Z.

2012-04-01

In situ considerate testing of surface cohesion of historic stone and mortar materials suffers from a lack of suitable affordable non-destructive methods. The problem is mainly important for assessment of surface degradation characteristics and/or evaluation of effectiveness of consolidation treatment of degraded historic materials. The paper presents two innovations of simple testing methods which provide reliable data on material cohesion and water uptake. The so called "Scotch Tape Test" or peeling test has been introduced into the field of conservation for testing the cohesion qualities of historic materials mainly stone and renders in sixties without any standards or reliably verified recommendations for the above mentioned application in the conservation practice. Licentious use without adequate knowledge and sufficient understanding leads to non-comparable and non-reproducible as well as in many cases incorrect and severely biased results and assessments. Therefore, the authors after a research and comparative testing have established limits for its application, reliable procedures and a "standard" protocol for testing of cohesion characteristics of brittle and quasi brittle materials mainly mortars and stones. This article presents a detailed analysis of the peeling test procedures, and suggests recommendations for performing peeling tests and for evaluating the obtained results. Also in situ testing of material water uptake is a very basic and indispensable technique in conservation practice and it correlates significantly with some other material characteristics. The capillary properties of porous materials can be measured in situ using a Karsten tube and modified tools or methods which are quite cumbersome, and cannot be performed on inclined surfaces, e.g. vaults or ceilings. There are other difficulties with Karsten tube measurements, e.g. problems with fixing a heavy glass tube on vertical surfaces, a need for two operators, and soiling of the surface by the sealing putty. An innovative method has therefore been developed and tested at ITAM AS CR for measuring water absorption under low pressure. It enables continuous or manually controlled electronic measurements of water infusion into the surface and recording the acquired data. This measurement procedure reduces the number of operators, and it is more precise, more effective and faster. Two prototypes will be presented: one for continuous laboratory measurements and a portable device for in situ applications. The portable device has been tested in laboratory conditions and also in situ for its basic performance on various types of stone and plaster surfaces, including treated and untreated historic materials. The acquired data was evaluated using software specially written for this purpose in MatLab, and the results were compared with standard capillary water uptake measurements on prismatic columns. Working with the innovated tubes, measurements can be made on complex stone or plaster surfaces, e.g. sculptures in a dense network. This feature is especially appreciated by restorers making interventions on materials that have been treated previously.

High Pressure Hydrogen Pressure Relief Devices: Accelerated Life Testing and Application Best Practices

DOE Office of Scientific and Technical Information (OSTI.GOV)

Burgess, Robert M.; Post, Matthew B.; Buttner, William J.

Pressure relief devices (PRDs ) are used to protect high pressure systems from burst failure caused by overpressurization. Codes and standards require the use of PRDs for the safe design of many pressurized systems. These systems require high reliability due to the risks associated with a burst failure. Hydrogen service can increase the risk of PRD failure due to material property degradation caused by hydrogen attack. The National Renewable Energy Laboratory (NREL) has conducted an accelerated life test on a conventional spring loaded PRD. Based on previous failures in the field, the nozzles specific to these PRDs are of particularmore » interest. A nozzle in a PRD is a small part that directs the flow of fluid toward the sealing surface to maintain the open state of the valve once the spring force is overcome. The nozzle in this specific PRD is subjected to the full tensile force of the fluid pressure. These nozzles are made from 440C material, which is a type of hardened steel that is commonly chosen for high pressure applications because of its high strength properties. In a hydrogen environment, however, 440C is considered a worst case material since hydrogen attack results in a loss of almost all ductility and thus 440C is prone to fatigue and material failure. Accordingly, 440C is not recommended for hydrogen service. Conducting an accelerated life test on a PRD with 440C material provides information on necessary and sufficient conditions required to produce crack initiation and failure. The accelerated life test also provides information on other PRD failure modes that are somewhat statistically random in nature.« less

Development of computer informational system of diagnostics integrated optical materials, elements, and devices

NASA Astrophysics Data System (ADS)

Volosovitch, Anatoly E.; Konopaltseva, Lyudmila I.

1995-11-01

Well-known methods of optical diagnostics, database for their storage, as well as expert system (ES) for their development are analyzed. A computer informational system is developed, which is based on a hybrid ES built on modern DBMS. As an example, the structural and constructive circuits of the hybrid integrated-optical devices based on laser diodes, diffusion waveguides, geodetic lenses, package-free linear photodiode arrays, etc. are presented. The features of methods and test results as well as the advanced directions of works related to the hybrid integrated-optical devices in the field of metrology are discussed.

Materials challenges for repeatable RF wireless device reconfiguration with microfluidic channels

NASA Astrophysics Data System (ADS)

Griffin, Anthony S.; Sottos, Nancy R.; White, Scott R.

2018-03-01

Recently, adaptive wireless devices have utilized displacement of EGaIn within microchannels as an electrical switching mechanism to enable reconfigurable electronics. Device reconfiguration using EGaIn in microchannels overcomes many challenges encountered by more traditional reconfiguration mechanisms such as diodes and microelectromechanical systems (MEMS). Reconfiguration using EGaIn is severely limited by undesired permanent shorting due to retention of the liquid in microchannels caused by wetting and rapid oxide skin formation. Here, we investigate the conditions which prevent repeatable electrical switching using EGaIn in microchannels. Initial contact angle tests of EGaIn on epoxy surfaces demonstrate the wettability of EGaIn on flat surfaces. SEM cross-sections of microchannels reveal adhesion of EGaIn residue to channel walls. Micro-computed tomography (microCT) scans of provide volumetric measurements of EGaIn remaining inside channels after flow cycling. Non-wetting coatings are proposed as materials based strategy to overcome these issues in future work.

Reconstruction of the domain orientation distribution function of polycrystalline PZT ceramics using vector piezoresponse force microscopy.

PubMed

Kratzer, Markus; Lasnik, Michael; Röhrig, Sören; Teichert, Christian; Deluca, Marco

2018-01-11

Lead zirconate titanate (PZT) is one of the prominent materials used in polycrystalline piezoelectric devices. Since the ferroelectric domain orientation is the most important parameter affecting the electromechanical performance, analyzing the domain orientation distribution is of great importance for the development and understanding of improved piezoceramic devices. Here, vector piezoresponse force microscopy (vector-PFM) has been applied in order to reconstruct the ferroelectric domain orientation distribution function of polished sections of device-ready polycrystalline lead zirconate titanate (PZT) material. A measurement procedure and a computer program based on the software Mathematica have been developed to automatically evaluate the vector-PFM data for reconstructing the domain orientation function. The method is tested on differently in-plane and out-of-plane poled PZT samples, and the results reveal the expected domain patterns and allow determination of the polarization orientation distribution function at high accuracy.

Materials, devices, techniques, and applications for Z-plane focal plane array technology II; Proceedings of the Meeting, San Diego, CA, July 12, 13, 1990

NASA Astrophysics Data System (ADS)

Carson, John C.

1990-11-01

Various papers on materials, devices, techniques, and applications for X-plane focal plane array technology are presented. Individual topics addressed include: application of Z-plane technology to the remote sensing of the earth from GEO, applications of smart neuromorphic focal planes, image-processing of Z-plane technology, neural network Z-plane implementation with very high interconnection rates, using a small IR surveillance satellite for tactical applications, establishing requirements for homing applications, Z-plane technology. Also discussed are: on-array spike suppression signal processing, algorithms for on-focal-plane gamma circumvention and time-delay integration, current HYMOSS Z-technology, packaging of electrons for on- and off-FPA signal processing, space/performance qualification of tape automated bonded devices, automation in tape automated bonding, high-speed/high-volume radiometric testing of Z-technology focal planes, 128-layer HYMOSS-module fabrication issues, automation of IRFPA production processes.

Development of Si/SiGe heterostructures

NASA Astrophysics Data System (ADS)

Hauenstein, R. J.; Veteran, J. L.; Young, M. H.

1991-01-01

New molecular beam epitaxy (MBE) materials growth and doping processes were developed for the fabrication of Si/SiGe heterostructure devices. These new materials processes are applied to the demonstration of cryogenic n-p-n Si/Si 1-x Gex/Si heterojunction bipolar transistors (HBT). This application has special significance as an enabling DoD technology for fast low noise, high performance readout and signal processing circuits for IR focal systems. Reliable, versatile methods were developed to grow very high quality Si/SiGe strained layer heterostructures and multilayers. In connection with this program methods were developed to dope the Si and SiGe with B, Sb and Ga. B and Sb were found to be the preferred dopants for p and n regions respectively, of the HBT devices. The test devices clearly displayed gain enhancement due to the heterojunction and provided useful gains from room temperature down to 10 K.

Plasma torch testing for thermostructural evaluation of rocket motor nozzle materials

NASA Technical Reports Server (NTRS)

Prince, Andrew S.; Bunker, Robert C.; Lawrence, Tim

1989-01-01

This paper presents data from the thermostructural testing of tape-wrapped carbon phenolic. This work has been performed with the use of a plasma torch and loading device in an effort to study the anomalous erosion characteristicfs of that seen in the Space Shuttle Solid Rocket Motor Nozzle STS-8A. Testing is conducted in an effort to determine conditions or parameters involved in this mode of failure.

Illusion thermal device based on material with constant anisotropic thermal conductivity for location camouflage

NASA Astrophysics Data System (ADS)

Hou, Quanwen; Zhao, Xiaopeng; Meng, Tong; Liu, Cunliang

2016-09-01

Thermal metamaterials and devices based on transformation thermodynamics often require materials with anisotropic and inhomogeneous thermal conductivities. In this study, still based on the concept of transformation thermodynamics, we designed a planar illusion thermal device, which can delocalize a heat source in the device such that the temperature profile outside the device appears to be produced by a virtual source at another position. This device can be constructed by only one kind of material with constant anisotropic thermal conductivity. The condition which should be satisfied by the device is provided, and the required anisotropic thermal conductivity is then deduced theoretically. This study may be useful for the designs of metamaterials or devices since materials with constant anisotropic parameters have great facility in fabrication. A prototype device has been fabricated based on a composite composed by two naturally occurring materials. The experimental results validate the effectiveness of the device.

Field Demonstration and Validation of a New Device for Measuring Water and Solute Fluxes at Naval Base Ventura County (NBVC), Port Hueneme, CA

DTIC Science & Technology

2006-07-01

All Quality Control Reference Materials are acquired only from authorized vendors or sources commonly used by U.S. EPA Regional Laboratories...are traceable to the National Institue of Standards and Testing (NITS) Standard Reference Materials (SRM) or to the U.S. EPA Reference Standards... clothing or equipment by blowing, shaking or any other means that may disperse material into the air is prohibited. 7.1.3. All disposable personal

Synthetic microfluidic paper: high surface area and high porosity polymer micropillar arrays.

PubMed

Hansson, Jonas; Yasuga, Hiroki; Haraldsson, Tommy; van der Wijngaart, Wouter

2016-01-21

We introduce Synthetic Microfluidic Paper, a novel porous material for microfluidic applications that consists of an OSTE polymer that is photostructured in a well-controlled geometry of slanted and interlocked micropillars. We demonstrate the distinct benefits of Synthetic Microfluidic Paper over other porous microfluidic materials, such as nitrocellulose, traditional paper and straight micropillar arrays: in contrast to straight micropillar arrays, the geometry of Synthetic Microfluidic Paper was miniaturized without suffering capillary collapse during manufacturing and fluidic operation, resulting in a six-fold increased internal surface area and a three-fold increased porous fraction. Compared to commercial nitrocellulose materials for capillary assays, Synthetic Microfluidic Paper shows a wider range of capillary pumping speed and four times lower device-to-device variation. Compared to the surfaces of the other porous microfluidic materials that are modified by adsorption, Synthetic Microfluidic Paper contains free thiol groups and has been shown to be suitable for covalent surface chemistry, demonstrated here for increasing the material hydrophilicity. These results illustrate the potential of Synthetic Microfluidic Paper as a porous microfluidic material with improved performance characteristics, especially for bioassay applications such as diagnostic tests.

Fabrication of 1-dimension nano-material-based device and its electrical characteristics

NASA Astrophysics Data System (ADS)

Yang, Xing; Zhou, Zhaoying; Zheng, Fuzhong; Zhang, Min

2008-12-01

In recent years, many kinds of 1-dimension nano-materials (Carbon nanotube, ZnO nanobelt and nanowire etc.) continue to emerge which exhibit distinct and unique electromechanical, piezoelectric, photoelectrical properties. In this paper, a 1-dimension nano-materials-based device was proposed. The bottom-up and top-down combined process were used for constructing CNT-array-based device and ZnO nanowire device. The electrical characteristics of the 1D nano-materials-based devices were also investigated. The measurement results of electrical characteristics demonstrate that it is ohm electrical contact behavior between the nano-material and micro-electrodes in the proposed device which also have the field effect. The proposed 1D nano-material-based device shows the application potential in the sensing fields.

Cooling device featuring thermoelectric and diamond materials for temperature control of heat-dissipating devices

NASA Technical Reports Server (NTRS)

Vandersande, Ian W. (Inventor); Ewell, Richard (Inventor); Fleurial, Jean-Pierre (Inventor); Lyon, Hylan B. (Inventor)

1998-01-01

A cooling device for lowering the temperature of a heat-dissipating device. The cooling device includes a heat-conducting substrate (composed, e.g., of diamond or another high thermal conductivity material) disposed in thermal contact with the heat-dissipating device. During operation, heat flows from the heat-dissipating device into the heat-conducting substrate, where it is spread out over a relatively large area. A thermoelectric cooling material (e.g., a Bi.sub.2 Te.sub.3 -based film or other thermoelectric material) is placed in thermal contact with the heat-conducting substrate. Application of electrical power to the thermoelectric material drives the thermoelectric material to pump heat into a second heat-conducting substrate which, in turn, is attached to a heat sink.

Adjustable Focus Optical Correction Lens (AFOCL)

NASA Technical Reports Server (NTRS)

Peters, Bruce R.

2001-01-01

This report describes the activities and accomplishments along with the status of the characterization of a PLZT-based Adjustable Focus Optical Correction Lens (AFOCL) test device. The activities described in this report were undertaken by members of the Center for Applied Optics (CAO) at the University of Alabama in Huntsville (UAH) under NASA Contract NAS8-00188. The effort was led by Dr. Bruce Peters as the Principal Investigator and supported by Dr. Patrick Reardon, Ms. Deborah Bailey, and graduate student Mr. Jeremy Wong. The activities outlined for the first year of the contract were to identify vendors and procure a test device along with performing the initial optical characterization of the test device. This activity has been successfully executed and test results are available and preliminary information was published at the SPIE Photonics West Conference in San Jose, January 2001. The paper, "Preliminary investigation of an active PLZT lens," was well received and generated response with several questions from the audience. A PLZT test device has been commercially procured from an outside vendor: The University of California in San Diego (UCSD) in partnership with New Interconnect Packaging Technologies (NIPT) Inc. The device has been subjected to several tests to characterize the optical performance of the device at wavelengths of interest. The goal was to evaluate the AFOCL similar to a conventional lens and measure any optical aberrations present due to the PLZT material as a deviation in the size of the diffraction limited spot (blur), the presence of diffracted energy into higher orders surrounding the focused spot (a variation in Strehl), and/or a variation or spread in the location of the focused energy away from the optical axis (a bias towards optical wedge, spherical, comma, or other higher order aberrations). While data has been collected indicative of the imaging quality of the AFOCL test device, it was not possible to fully characterize the optical performance of the AFOCL alone because there were significant optical distortions due to fabrication related issues.

Innovative Anti Crash Absorber for a Crashworthy Landing Gear

NASA Astrophysics Data System (ADS)

Guida, Michele; Marulo, Francesco; Montesarchio, Bruno; Bruno, Massimiliano

2014-06-01

This paper defines an innovative concept to anti-crash absorber in composite material to be integrated on the landing gear as an energy-absorbing device in crash conditions to absorb the impact energy. A composite cylinder tube in carbon fiber material is installed coaxially to the shock absorber cylinder and, in an emergency landing gear condition, collapses in order to enhance the energy absorption performance of the landing system. This mechanism has been developed as an alternative solution to a high-pressure chamber installed on the Agusta A129 CBT helicopter, which can be considered dangerous when the helicopter operates in hard and/or crash landing. The characteristics of the anti-crash device are presented and the structural layout of a crashworthy landing gear adopting the developed additional energy absorbing stage is outlined. Experimental and numerical results relevant to the material characterization and the force peaks evaluation of the system development are reported. The anti-crash prototype was designed, analysed, optimized, made and finally the potential performances of a landing gear with the additional anti-crash absorber system are tested by drop test and then correlated with a similar test without the anti-crash system, showing that appreciable energy absorbing capabilities and efficiencies can be obtained in crash conditions.

Nature-Inspired Structural Materials for Flexible Electronic Devices.

PubMed

Liu, Yaqing; He, Ke; Chen, Geng; Leow, Wan Ru; Chen, Xiaodong

2017-10-25

Exciting advancements have been made in the field of flexible electronic devices in the last two decades and will certainly lead to a revolution in peoples' lives in the future. However, because of the poor sustainability of the active materials in complex stress environments, new requirements have been adopted for the construction of flexible devices. Thus, hierarchical architectures in natural materials, which have developed various environment-adapted structures and materials through natural selection, can serve as guides to solve the limitations of materials and engineering techniques. This review covers the smart designs of structural materials inspired by natural materials and their utility in the construction of flexible devices. First, we summarize structural materials that accommodate mechanical deformations, which is the fundamental requirement for flexible devices to work properly in complex environments. Second, we discuss the functionalities of flexible devices induced by nature-inspired structural materials, including mechanical sensing, energy harvesting, physically interacting, and so on. Finally, we provide a perspective on newly developed structural materials and their potential applications in future flexible devices, as well as frontier strategies for biomimetic functions. These analyses and summaries are valuable for a systematic understanding of structural materials in electronic devices and will serve as inspirations for smart designs in flexible electronics.

Examinations for leak tightness of actively cooled components in ITER and fusion devices

NASA Astrophysics Data System (ADS)

Hirai, T.; Barabash, V.; Carrat, R.; Chappuis, Ph; Durocher, A.; Escourbiac, F.; Merola, M.; Raffray, R.; Worth, L.; Boscary, J.; Chantant, M.; Chuilon, B.; Guilhem, D.; Hatchressian, J.-C.; Hong, S. H.; Kim, K. M.; Masuzaki, S.; Mogaki, K.; Nicolai, D.; Wilson, D.; Yao, D.

2017-12-01

Any leak in one of the ITER actively cooled components would cause significant consequences for machine operations; therefore, the risk of leak must be minimized as much as possible. In this paper, the strategy of examination to ensure leak tightness of the ITER internal components (i.e. examination of base materials, vacuum boundary joints and final components) and the hydraulic parameters for ITER internal components are summarized. The experiences of component tests, especially hot helium leak tests in recent fusion devices, were reviewed and the parameters were discussed. Through these experiences, it was confirmed that the hot He leak test was effective to detect small leak paths which were not always possible to detect by volumetric examination due to limited spatial resolution.

Chemical speciation of U, Fe, and Pu in melt glass from nuclear weapons testing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pacold, J. I.; Lukens, W. W.; Booth, C. H.

Nuclear weapons testing generates large volumes of glassy materials that influence the transport of dispersed actinides in the environment and may carry information on the composition of the detonated device. We determine the oxidation state of U and Fe (which is known to buffer the oxidation state of actinide elements and to affect the redox state of groundwater) in samples of melt glass collected from three U.S. nuclear weapons tests. For selected samples, we also determine the coordination geometry of U and Fe, and we report the oxidation state of Pu from one melt glass sample. We find significant variationsmore » among the melt glass samples and, in particular, find a clear deviation in one sample from the expected buffering effect of Fe(II)/Fe(III) on the oxidation state of uranium. In the first direct measurement of Pu oxidation state in a nuclear test melt glass, we obtain a result consistent with existing literature that proposes Pu is primarily present as Pu(IV) in post-detonation material. In addition, our measurements imply that highly mobile U(VI) may be produced in significant quantities when melt glass is quenched rapidly following a nuclear detonation, though these products may remain immobile in the vitrified matrices. The observed differences in chemical state among the three samples show that redox conditions can vary dramatically across different nuclear test conditions. The local soil composition, associated device materials, and the rate of quenching are all likely to affect the final redox state of the glass. The resulting variations in glass chemistry are significant for understanding and interpreting debris chemistry and the later environmental mobility of dispersed material.« less

Chemical speciation of U, Fe, and Pu in melt glass from nuclear weapons testing

DOE Office of Scientific and Technical Information (OSTI.GOV)

Pacold, J. I.; Lukens, W. W.; Booth, C. H.

We report that nuclear weapons testing generates large volumes of glassy materials that influence the transport of dispersed actinides in the environment and may carry information on the composition of the detonated device. We determine the oxidation state of U and Fe (which is known to buffer the oxidation state of actinide elements and to affect the redox state of groundwater) in samples of melt glass collected from three U.S. nuclear weapons tests. For selected samples, we also determine the coordination geometry of U and Fe, and we report the oxidation state of Pu from one melt glass sample. Wemore » find significant variations among the melt glass samples and, in particular, find a clear deviation in one sample from the expected buffering effect of Fe(II)/Fe(III) on the oxidation state of uranium. In the first direct measurement of Pu oxidation state in a nuclear test melt glass, we obtain a result consistent with existing literature that proposes Pu is primarily present as Pu(IV) in post-detonation material. In addition, our measurements imply that highly mobile U(VI) may be produced in significant quantities when melt glass is quenched rapidly following a nuclear detonation, though these products may remain immobile in the vitrified matrices. The observed differences in chemical state among the three samples show that redox conditions can vary dramatically across different nuclear test conditions. The local soil composition, associated device materials, and the rate of quenching are all likely to affect the final redox state of the glass. Lastly, the resulting variations in glass chemistry are significant for understanding and interpreting debris chemistry and the later environmental mobility of dispersed material.« less

Chemical speciation of U, Fe, and Pu in melt glass from nuclear weapons testing

DOE PAGES

Pacold, J. I.; Lukens, W. W.; Booth, C. H.; ...

2016-05-18

We report that nuclear weapons testing generates large volumes of glassy materials that influence the transport of dispersed actinides in the environment and may carry information on the composition of the detonated device. We determine the oxidation state of U and Fe (which is known to buffer the oxidation state of actinide elements and to affect the redox state of groundwater) in samples of melt glass collected from three U.S. nuclear weapons tests. For selected samples, we also determine the coordination geometry of U and Fe, and we report the oxidation state of Pu from one melt glass sample. Wemore » find significant variations among the melt glass samples and, in particular, find a clear deviation in one sample from the expected buffering effect of Fe(II)/Fe(III) on the oxidation state of uranium. In the first direct measurement of Pu oxidation state in a nuclear test melt glass, we obtain a result consistent with existing literature that proposes Pu is primarily present as Pu(IV) in post-detonation material. In addition, our measurements imply that highly mobile U(VI) may be produced in significant quantities when melt glass is quenched rapidly following a nuclear detonation, though these products may remain immobile in the vitrified matrices. The observed differences in chemical state among the three samples show that redox conditions can vary dramatically across different nuclear test conditions. The local soil composition, associated device materials, and the rate of quenching are all likely to affect the final redox state of the glass. Lastly, the resulting variations in glass chemistry are significant for understanding and interpreting debris chemistry and the later environmental mobility of dispersed material.« less

Chemical speciation of U, Fe, and Pu in melt glass from nuclear weapons testing

NASA Astrophysics Data System (ADS)

Pacold, J. I.; Lukens, W. W.; Booth, C. H.; Shuh, D. K.; Knight, K. B.; Eppich, G. R.; Holliday, K. S.

2016-05-01

Nuclear weapons testing generates large volumes of glassy materials that influence the transport of dispersed actinides in the environment and may carry information on the composition of the detonated device. We determine the oxidation state of U and Fe (which is known to buffer the oxidation state of actinide elements and to affect the redox state of groundwater) in samples of melt glass collected from three U.S. nuclear weapons tests. For selected samples, we also determine the coordination geometry of U and Fe, and we report the oxidation state of Pu from one melt glass sample. We find significant variations among the melt glass samples and, in particular, find a clear deviation in one sample from the expected buffering effect of Fe(II)/Fe(III) on the oxidation state of uranium. In the first direct measurement of Pu oxidation state in a nuclear test melt glass, we obtain a result consistent with existing literature that proposes Pu is primarily present as Pu(IV) in post-detonation material. In addition, our measurements imply that highly mobile U(VI) may be produced in significant quantities when melt glass is quenched rapidly following a nuclear detonation, though these products may remain immobile in the vitrified matrices. The observed differences in chemical state among the three samples show that redox conditions can vary dramatically across different nuclear test conditions. The local soil composition, associated device materials, and the rate of quenching are all likely to affect the final redox state of the glass. The resulting variations in glass chemistry are significant for understanding and interpreting debris chemistry and the later environmental mobility of dispersed material.

High mobility high efficiency organic films based on pure organic materials

DOEpatents

Salzman, Rhonda F [Ann Arbor, MI; Forrest, Stephen R [Ann Arbor, MI

2009-01-27

A method of purifying small molecule organic material, performed as a series of operations beginning with a first sample of the organic small molecule material. The first step is to purify the organic small molecule material by thermal gradient sublimation. The second step is to test the purity of at least one sample from the purified organic small molecule material by spectroscopy. The third step is to repeat the first through third steps on the purified small molecule material if the spectroscopic testing reveals any peaks exceeding a threshold percentage of a magnitude of a characteristic peak of a target organic small molecule. The steps are performed at least twice. The threshold percentage is at most 10%. Preferably the threshold percentage is 5% and more preferably 2%. The threshold percentage may be selected based on the spectra of past samples that achieved target performance characteristics in finished devices.

MISSE 6-Testing Materials in Space

NASA Technical Reports Server (NTRS)

Prasad, Narasimha S; Kinard, William H.

2008-01-01

The objective of the Materials International Space Station Experiment (MISSE) is to study the performance of novel materials when subjected to the synergistic effects of the harsh space environment by placing them in space environment for several months. In this paper, a few materials and components from NASA Langley Research Center (LaRC) that have been flown on MISSE 6 mission will be discussed. These include laser and optical elements for photonic devices. The pre-characterized MISSE 6 materials were packed inside a ruggedized Passive Experiment Container (PEC) that resembles a suitcase. The PEC was tested for survivability due to launch conditions. Subsequently, the MISSE 6 PEC was transported by the STS-123 mission to International Space Station (ISS) on March 11, 2008. The astronauts successfully attached the PEC to external handrails and opened the PEC for long term exposure to the space environment.

Sublimation measurements and analysis of high temperature thermoelectric materials and devices

NASA Technical Reports Server (NTRS)

Shields, V.; Noon, L.

1983-01-01

High temperature thermoelectric device sublimation effects are compared for rare earth sulfides, selenides, and state-of-the-art Si-Ge alloys. Although rare earth calcogenides can potentially exhibit superior sublimation characteristics, the state-of-the-art Si-Ge alloy with silicon nitride sublimation-inhibitive coating has been tested to 1000 C. Attention is given to the ceramic electrolyte cells, forming within electrical and thermal insulation, which affect leakage conductance measurements in Si-Ge thermoelectric generators.

Damping in Materials for Spintronic Applications

NASA Astrophysics Data System (ADS)

Mewes, Claudia

The next generation of spintronic devices relies strongly on the development of new materials with high spin polarization, optimized intrinsic damping and tunable magnetic anisotropy. Therefore, technological progress in this area depends heavily on the successful search for new materials as well as on a deeper understanding of the fundamental mechanisms of the spin polarization, the damping and the magnetic anisotropy. This talk will focus on different aspects of materials with a low intrinsic relaxation rate. Our results are based on first principles calculations in combination with a non-orthogonal tight-binding model to predict those material properties for complex materials which can be used for example in new spin based memory devices or logic devices. However, the intrinsic damping parameter predicted from first principle calculations does not take into account adjacent layers that are present in the final device. Spin pumping is a well-known contribution that has to be taken into account for practical applications using multilayer structures. More recently a strong unidirectional contribution to the relaxation in exchange bias systems has been observed experimentally. To describe this phenomenon theoretically we use the formalism of an anisotropic Gilbert damping tensor that takes the place of the (scalar) Gilbert damping parameter in the Landau-Lifshitz-Gilbert equation of motion. While for single crystals this anisotropy is expected to be small, making experimental confirmation difficult, the broken symmetry in exchange bias systems provides an excellent testing ground to study the modified magnetization dynamics under the influence of unidirectional damping. C.K.A. Mewes would like to thank her colleague T. Mewes and her students J.B. Mohammadi, A.E. Farrar. We acknowledge support by the NSF-CAREER Award No. 1452670, and NSF-CAREER Award No. 0952929.

Novel folding device for manufacturing aerospace composite structures

NASA Astrophysics Data System (ADS)

Tewfic, Tarik; Sarhadi, M.

2000-10-01

A new manufacturing methodology, termed shape-inclusive lay-up has been applied that allows the generation of three-dimensional preforms for the resin transfer molding (RTM) process. A flexible novel folding device for forming dry fabrics including non-crimp fabric (NCF) preform is designed and integrated with a Material Delivery System (MDS) into a robotic cell for manufacturing dry fiber composite aerospace components. The paper describes detailed design, implementation and operational performance of a prototype device. The proposed folding device has been implemented and tested by manufacturing a range of reinforcement structure preforms (C,T,J and I reinforcement preforms), normally used in aerostructure applications. A key advantage of the proposed device is its flexibility. The system is capable of manufacturing a wide range of components of various sizes without the need for reconfiguration.

A catalogue of devices applicable to the measurement of boundary layers and wakes on flight vehicles

NASA Technical Reports Server (NTRS)

Miley, S. J.

1972-01-01

A literature search was conducted to assemble a catalog of devices and techniques which have possible application to boundary layer and wake measurements on flight vehicles. The indices used in the search were NACA, NASA STAR, IAA, USGRDR and Applied Science and Technology Index. The period covered was 1950 through 1970. The devices contained in the catalog were restricted to those that provided essentially direct measurement of velocities, pressures and shear stresses. Pertinent material was included in the catalog if it contained either an adequate description of a device and associated performance data or a presentation of applicable information on a particular measurement theory and/or technique. When available, illustrations showing the configuration of the device and test condition data were also included.

Changes in the Mg profile and in dislocations induced by high temperature annealing of blue LEDs

NASA Astrophysics Data System (ADS)

Meneghini, M.; Trivellin, N.; Berti, M.; Cesca, T.; Gasparotto, A.; Vinattieri, A.; Bogani, F.; Zhu, D.; Humphreys, C. J.; Meneghesso, G.; Zanoni, E.

2013-03-01

The efficiency of the injection and recombination processes in InGaN/GaN LEDs is governed by the properties of the active region of the devices, which strongly depend on the conditions used for the growth of the epitaxial material. To improve device quality, it is very important to understand how the high temperatures used during the growth process can modify the quality of the epitaxial material. With this paper we present a study of the modifications in the properties of InGaN/GaN LED structures induced by high temperature annealing: thermal stress tests were carried out at 900 °C, in nitrogen atmosphere, on selected samples. The efficiency and the recombination dynamics were evaluated by photoluminescence measurements (both integrated and time-resolved), while the properties of the epitaxial material were studied by Secondary Ion Mass Spectroscopy (SIMS) and Rutherford Backscattering (RBS) channeling measurements. Results indicate that exposure to high temperatures may lead to: (i) a significant increase in the photoluminescence efficiency of the devices; (ii) a decrease in the parasitic emission bands located between 380 nm and 400 nm; (iii) an increase in carrier lifetime, as detected by time-resolved photoluminescence measurements. The increase in device efficiency is tentatively ascribed to an improvement in the crystallographic quality of the samples.

Development of a MEMS device for acoustic emission testing

NASA Astrophysics Data System (ADS)

Ozevin, Didem; Pessiki, Stephen P.; Jain, Akash; Greve, David W.; Oppenheim, Irving J.

2003-08-01

Acoustic emission testing is an important technology for evaluating structural materials, and especially for detecting damage in structural members. Significant new capabilities may be gained by developing MEMS transducers for acoustic emission testing, including permanent bonding or embedment for superior coupling, greater density of transducer placement, and a bundle of transducers on each device tuned to different frequencies. Additional advantages include capabilities for maintenance of signal histories and coordination between multiple transducers. We designed a MEMS device for acoustic emission testing that features two different mechanical types, a hexagonal plate design and a spring-mass design, with multiple detectors of each type at ten different frequencies in the range of 100 kHz to 1 MHz. The devices were fabricated in the multi-user polysilicon surface micromachining (MUMPs) process and we have conducted electrical characterization experiments and initial experiments on acoustic emission detection. We first report on C(V) measurements and perform a comparison between predicted (design) and measured response. We next report on admittance measurements conducted at pressures varying from vacuum to atmospheric, identifying the resonant frequencies and again providing a comparison with predicted performance. We then describe initial calibration experiments that compare the performance of the detectors to other acoustic emission transducers, and we discuss the overall performance of the device as a sensor suite, as contrasted to the single-channel performance of most commercial transducers.

Development of advanced test methods for the improvement of production standards for ceramic powders used in solid oxide fuel cells

NASA Astrophysics Data System (ADS)

Ward, Brian

Solid oxide fuel cells (SOFCs) are energy conversion devices that use ceramic powders as a precursor material for their electrodes. Presently, powder manufacturers are encountering complications producing consistent precursor powders. Through various thermal, chemical and physical tests, such as DSC and XRD, a preliminary production standard will be developed.

Testing Devices Garner Data on Insulation Performance

NASA Technical Reports Server (NTRS)

2014-01-01

To develop a test instrument that could garner measurements of the thermal performance of insulation under extreme conditions, researchers at Kennedy Space Center devised the Cryostat 1 and then Cryostat 2. McLean, Virginia-based QinetiQ North America licensed the technology and plans to market it to organizations developing materials for things like piping and storage tank insulation, refrigeration, appliances, and consumer goods.

The wear properties of CFR-PEEK-OPTIMA articulating against ceramic assessed on a multidirectional pin-on-plate machine.

PubMed

Scholes, S C; Unsworth, A

2007-04-01

In an attempt to prolong the lives of rubbing implantable devices, several 'new' materials have been examined to determine their suitability as joint couplings. Tests were performed on a multidirectional pin-on-plate machine to determine the wear of both pitch and PAN (polyacrylonitrile)-based carbon fibre reinforced-polyetheretherketone (CFR-PEEK-OPTIMA) pins articulating against both BioLox Delta and BioLox Forte plates (ceramic materials). Both reciprocation and rotational motion were applied to the samples. The tests were conducted using 24.5 per cent bovine serum as the lubricant (protein concentration 15 g/l). Although all four material combinations gave similar low wear with no statistically significant difference (p > 0.25), the lowest average total wear of these pin-on-plate tests was provided by CFR-PEEK-OPTIMA pitch pins versus BioLox Forte plates. This was much lower than the wear produced by conventional joint materials (metal-on-polyethylene) and metal-on-metal combinations when tested on the pin-on-plate machine. This therefore indicates optimism that these PEEK-OPTIMA-based material combinations may perform well in joint applications.

Transparent conductors based on microscale/nanoscale materials for high performance devices

NASA Astrophysics Data System (ADS)

Gao, Tongchuan

Transparent conductors are important as the top electrode for a variety of optoelectronic devices, including solar cells, light-emitting diodes (LEDs), at panel displays, and touch screens. Doped indium tin oxide (ITO) thin films are the predominant transparent conductor material. However, ITO thin films are brittle, making them unsuitable for the emerging flexible devices, and suffer from high material and processing cost. In my thesis, we developed a variety of transparent conductors toward a performance comparable with or superior to ITO thin films, with lower cost and potential for scalable manufacturing. Metal nanomesh (NM), hierarchical graphene/metal microgrid (MG), and hierarchical metal NM/MG materials were investigated. Simulation methods were used as a powerful tool to predict the transparency and sheet resistance of the transparent conductors by solving Maxwell's equations and Poisson's equation. Affordable and scalable fabrication processes were developed thereafter. Transparent conductors with over 90% transparency and less than 10 O/square sheet resistance were successfully fabricated on both rigid and flexible substrates. Durability tests, such as bending, heating and tape tests, were carried out to evaluate the robustness of the samples. Haze factor, which characterizes how blurry a transparent conductor appears, was also studied in-depth using analytical calculation and numerical simulation. We demonstrated a tunable haze factor for metal NM transparent conductors and analyzed the principle for tuning the haze factor. Plasmonic effects, excited by some transparent conductors, can lead to enhanced performance in photovoltaic devices. We systematically studied the effect of incorporating metal NM into ultrathin film silicon solar cells using numerical simulation, with the aid of optimization algorithms to reduce the optimization time. Mechanisms contributing to the enhanced performance were then identified and analyzed. Over 72% enhancement in short-circuit current-density was demonstrated by the optimal solar cell compared with 300-nm-thick Si solar cell with antireflection coating and silver back reflector.

Current and Perspective Applications of Dense Plasma Focus Devices

NASA Astrophysics Data System (ADS)

Gribkov, V. A.

2008-04-01

Dense Plasma Focus (DPF) devices' applications, which are intended to support the main-stream large-scale nuclear fusion programs (NFP) from one side (both in fundamental problems of Dense Magnetized Plasma physics and in its engineering issues) as well as elaborated for an immediate use in a number of fields from the other one, are described. In the first direction such problems as self-generated magnetic fields, implosion stability of plasma shells having a high aspect ratio, etc. are important for the Inertial Confinement Fusion (ICF) programs (e.g. as NIF), whereas different problems of current disruption phenomenon, plasma turbulence, mechanisms of generation of fast particles and neutrons in magnetized plasmas are of great interest for the large devices of the Magnetic Plasma Confinement—MPC (e.g. as ITER). In a sphere of the engineering problems of NFP it is shown that in particular the radiation material sciences have DPF as a very efficient tool for radiation tests of prospect materials and for improvement of their characteristics. In the field of broad-band current applications some results obtained in the fields of radiation material sciences, radiobiology, nuclear medicine, express Neutron Activation Analysis (including a single-shot interrogation of hidden illegal objects), dynamic non-destructive quality control, X-Ray microlithography and micromachining, and micro-radiography are presented. As the examples of the potential future applications it is proposed to use DPF as a powerful high-flux neutron source to generate very powerful pulses of neutrons in the nanosecond (ns) range of its duration for innovative experiments in nuclear physics, for the goals of radiation treatment of malignant tumors, for neutron tests of materials of the first wall, blankets and NFP device's constructions (with fluences up to 1 dpa per a year term), and ns pulses of fast electrons, neutrons and hard X-Rays for brachytherapy.

High-speed droplet actuation on single-plate electrode arrays.

PubMed

Banerjee, Arghya Narayan; Qian, Shizhi; Joo, Sang Woo

2011-10-15

This paper reports a droplet-based microfluidic device composed of patterned co-planar electrodes in an all-in-a-single-plate arrangement and coated with dielectric layers for electrowetting-on-dielectric (EWOD) actuation of discrete droplets. The co-planar arrangement is preferred over conventional two-plate electrowetting devices because it provides simpler manufacturing process, reduced viscous drag, and easier liquid-handling procedures. These advantages lead to more versatile and efficient microfluidic devices capable of generating higher droplet speed and can incorporate various other droplet manipulation functions into the system for biological, sensing, and other microfluidic applications. We have designed, fabricated, and tested the devices using an insulating layer with materials having relatively high dielectric constant (SiO(2)) and compared the results with polymer coatings (Cytop) with low dielectric constant. Results show that the device with high dielectric layer generates more reproducible droplet transfer over a longer distance with a 25% reduction in the actuation voltage with respect to the polymer coatings, leading to more energy efficient microfluidic applications. We can generate droplet speeds as high as 26 cm/s using materials with high dielectric constant such as SiO(2). Copyright © 2011. Published by Elsevier Inc.

Atmospheric simulation using a liquid crystal wavefront-controlling device

NASA Astrophysics Data System (ADS)

Brooks, Matthew R.; Goda, Matthew E.

2004-10-01

Test and evaluation of laser warning devices is important due to the increased use of laser devices in aerial applications. This research consists of an atmospheric aberrating system to enable in-lab testing of various detectors and sensors. This system employs laser light at 632.8nm from a Helium-Neon source and a spatial light modulator (SLM) to cause phase changes using a birefringent liquid crystal material. Measuring outgoing radiation from the SLM using a CCD targetboard and Shack-Hartmann wavefront sensor reveals an acceptable resemblance of system output to expected atmospheric theory. Over three turbulence scenarios, an error analysis reveals that turbulence data matches theory. A wave optics computer simulation is created analogous to the lab-bench design. Phase data, intensity data, and a computer simulation affirm lab-bench results so that the aberrating SLM system can be operated confidently.

Component Selection, Accelerated Testing, and Improved Modeling of AMTEC Systems for Space Power (abstract)

NASA Technical Reports Server (NTRS)

Williams, R. M.; Jeffries-Nakamura, B.; Ryan, M. A.; Underwood, M. L.; Suitor, J.; O'Connor, D.

1993-01-01

Alkali metal thermal to electric converter (AMTEC) designs for space power are numerous, but selection of materials for construction of long-lived AMTEC devices has been limited to electrodes, current collectors, and the solid electrolyte. AMTEC devices with lifetimes greater than 5 years require careful selection and life testing of all hot-side components. The likely selection of a remote condensed design for initial flight test and probable use with a GPHS in AMTEC powered outer planet probes requires the device to be constructed to tolerate T greater than 1150K, as well as exposure to Na(sub (g)), and Na(sub (liq)) on the high pressure side. The temperatures involved make critical high strength and chemical resistance to Na containing Na(sub 2)O. Selection among materials which can be worked should not be driven by ease of fabricability, as high temperature stability is the critical issue. These concepts drive the selection of Mo alloys for Na(sub (liq)) containment in AMTEC cells for T to 1150K operation, as they are significantly stronger than comparable NB or Ta alloys, are less soluble in Na(sub (liq)) containing dissolved Na(sub 2)O, are workable compared to W alloys (which might be used for certain components), and are ductile at the T greater than 500K of proposed AMTEC modules in space applications.

Modeling the impact of thermal effects on luminous flux maintenance for SSL luminaires

DOE Office of Scientific and Technical Information (OSTI.GOV)

Davis, Lynn; Mills, Karmann; Lamvik, Michael

Meeting the longevity requirements of solid-state lighting (SSL) devices places extreme demands on the materials and designs that are used in SSL luminaires. Therefore, understanding the aging characteristics of lens, reflectors, and other materials is essential to projecting the long-term performance of LED-based lighting systems. Overlooking these factors at either the design or product specification stage can result in premature failure of the device due to poor luminous flux maintenance and/or excessive chromaticity shifts. This paper describes a methodology for performing accelerated stress testing (AST) on materials intended for use in SSL luminaires. This test methodology, which consists of elevatedmore » temperature and humidity conditions, produces accelerated aging data that can be correlated to expected performance under normal luminaire operating conditions. The correlations can then be leveraged to produce models of the changes in the optical properties of key materials including transmittance versus wavelength of lenses and reflectance versus wavelength for housings and other reflectors. This information has been collected into a lumen maintenance decision support tool (LM-DST) and together with user supplied inputs (e.g., expected operation conditions) can provide guidance on lifetime expectations of SSL luminaires. This approach has been applied to a variety of materials commonly found in SSL luminaires including acrylics, polycarbonates, and silicones used for lenses and paints, coatings, films, and composites used for reflectors.« less

Solution Based Functionalization of Nanostructured Oxides with Organic Molecules

NASA Astrophysics Data System (ADS)

Pearce, Brady Lawrence

The surface modification of wide bandgap semiconductors with organic molecules provides novel functionalities to the composite material. These functionalities can include tuning of the optical properties, providing solution stability of the inorganic material, as well as many others. The use of an in-situ functionalization method for surface attachment of phosphonic group containing molecules to the surface of gallium nitride (GaN) has shown promise. This technique is particularly advantageous due to the etching and functionalization steps occurring at the same time, in the same beaker, as well as not being reliant on organic solvents or high temperatures. In this functionalization process, surface hydroxide groups are preferentially grown on the surface of GaN, which serve as attachment sites for phosphonic groups on organic moieties. Molecules with these hydroxyl groups available natively on their surface, such as AlOOH and GaOOH, provide a unique advantage. The requirement for an etching step is removed, and the functionalization process could be performed in a simple one-step modification. The work in this dissertation seeks to address the possibility of using these materials as the inorganic component in organic/inorganic composite material in devices. Of particular importance in solar cell and bioelectronic devices is the ability to withstand varying pH environments, and to avoid the leaching of toxic ionic species. Lysine has shown to reduce the leaching of ionic species, when particles of inorganic molecules are cross-linking agents for the amino acid. In this work, the aqueous stability of both AlOOH and GaOOH in a lysine environment will be explored. The optical and size characteristics observed in nanostructured forms of the mixed composition AlxGa1-xOOH material system is of interest, due optical tunability providing a distinct advantage in optoelectronic devices containing these organic/inorganic hybrids. Immobilizing phosphonic group containing organic dyes on the surface of GaN, GaOOH, AlOOH and mixed compositions of AlGaOOH using surface bonding sites, and possible covalent attachments mechanisms, seeks to provide an improvement in the long term stability of the inorganic/organic interface for devices. Future work in this area will test device efficiency using these hybrids, explore additional mixed oxyhydroxide composition systems and continue the advancement of the understanding of the important role of phosphonic groups in organic/inorganic devices. The nature of chemical and surface species in these materials will be characterized with Fourier Transformed-Infrared Spectroscopy (FT-IR) and X-Ray Photoelectric Spectroscopy (XPS). The optical properties of the materials were tested with photoluminescence (PL) spectroscopy, and the stability was examined with fluorescence spectroscopy. The crystallographic nature of the nanostructured inorganic materials before and after functionalization was determined with X-Ray Diffraction (XRD). Images of the nanostructures were obtained with mainly Scanning Electron Microscopy (SEM) as well as Transmission Electron Microscopy (TEM). The work in this dissertation seeks to address the improvement of the development of nanostructured inorganic/organic hybrid materials, the investigation of novel composites for these applications and the improvement of the long term stability in aqueous medium as well as of the organic/inorganic interface itself.

KENNEDY SPACE CENTER, FLA. - On a tour of the KSC Beach Corrosion Test Site, Testbed Manager Louis MacDowell (right) explains to Center Director Jim Kennedy about the test blocks being used to test a newly developed coating to protect steel inside concrete. Between MacDowell and Kennedy are Dr. Paul Hintze and Lead Scientist Dr. Luz Marina Calle. The KSC Beach Corrosion Test Site was established in the 1960s and has provided more than 30 years of historical information on the long-term performance of many materials in use at KSC and other locations around the world. Located 100 feet from the Atlantic Ocean approximately 1 mile south of the Space Shuttle launch sites, the test facility includes an atmospheric exposure site, a flowing seawater exposure site, and an on-site electrochemistry laboratory and monitoring station. The beach laboratory is used to conduct real-time corrosion experiments and provides for the remote monitoring of surrounding weather conditions. The newly added flowing seawater immersion facility provides for the immersion testing of materials and devices under controlled conditions.

NASA Image and Video Library

2003-08-21

KENNEDY SPACE CENTER, FLA. - On a tour of the KSC Beach Corrosion Test Site, Testbed Manager Louis MacDowell (right) explains to Center Director Jim Kennedy about the test blocks being used to test a newly developed coating to protect steel inside concrete. Between MacDowell and Kennedy are Dr. Paul Hintze and Lead Scientist Dr. Luz Marina Calle. The KSC Beach Corrosion Test Site was established in the 1960s and has provided more than 30 years of historical information on the long-term performance of many materials in use at KSC and other locations around the world. Located 100 feet from the Atlantic Ocean approximately 1 mile south of the Space Shuttle launch sites, the test facility includes an atmospheric exposure site, a flowing seawater exposure site, and an on-site electrochemistry laboratory and monitoring station. The beach laboratory is used to conduct real-time corrosion experiments and provides for the remote monitoring of surrounding weather conditions. The newly added flowing seawater immersion facility provides for the immersion testing of materials and devices under controlled conditions.

21 CFR 872.3930 - Bone grafting material.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Bone grafting material. 872.3930 Section 872.3930...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3930 Bone grafting material. (a) Identification. Bone grafting material is a material such as hydroxyapatite, tricalcium phosphate, polylactic and...

21 CFR 872.3930 - Bone grafting material.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Bone grafting material. 872.3930 Section 872.3930...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3930 Bone grafting material. (a) Identification. Bone grafting material is a material such as hydroxyapatite, tricalcium phosphate, polylactic and...

21 CFR 872.3930 - Bone grafting material.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Bone grafting material. 872.3930 Section 872.3930...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3930 Bone grafting material. (a) Identification. Bone grafting material is a material such as hydroxyapatite, tricalcium phosphate, polylactic and...

21 CFR 872.3930 - Bone grafting material.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Bone grafting material. 872.3930 Section 872.3930...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3930 Bone grafting material. (a) Identification. Bone grafting material is a material such as hydroxyapatite, tricalcium phosphate, polylactic and...

21 CFR 872.3930 - Bone grafting material.

Code of Federal Regulations, 2010 CFR

2010-04-01

... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Bone grafting material. 872.3930 Section 872.3930...) MEDICAL DEVICES DENTAL DEVICES Prosthetic Devices § 872.3930 Bone grafting material. (a) Identification. Bone grafting material is a material such as hydroxyapatite, tricalcium phosphate, polylactic and...

Field-Effect Flow Control for 2-D and 3-D Microfluidics

DTIC Science & Technology

2006-02-13

goal of achieving 75% transfer efficiency. The test devices with 3-D channels were fabricated in PDMS polymer (Figure la & lb) and the pumping...properties of a variety of polymer substrate materials were investigated to determine the material that was most amenable to the laser-induced...fluorescence detection employed in this project. Different polymer samples were obtained from different companies and are listed in Table 1 below. Field

Torsional Shear Device for Testing the Dynamic Properties of Recycled Material

NASA Astrophysics Data System (ADS)

Gabryś, Katarzyna; Sas, Wojciech; Soból, Emil; Głuchowski, Andrzej

2016-12-01

From the viewpoint of environmental preservation and effective utilization of resources, it is beneficial and necessary to reuse wastes, for example, concrete, as the recycled aggregates for new materials. In this work, the dynamic behavior of such aggregates under low frequency torsional loading is studied. Results show that the properties of such artificial soils match with those reported in the literature for specific natural soils.

An experimental investigation of using carbon foam-PCM-MWCNTs composite materials for thermal management of electronic devices under pulsed power modes

NASA Astrophysics Data System (ADS)

Alshaer, W. G.; Rady, M. A.; Nada, S. A.; Palomo Del Barrio, Elena; Sommier, Alain

2017-02-01

The present article reports on a detailed experimental investigation of using carbon foam-PCM-MWCNTs composite materials for thermal management (TM) of electronic devices subjected to pulsed power. The TM module was fabricated by infiltrating paraffin wax (RT65) as a phase change material (PCM) and multi walled carbon nanotubes (MWCNTs) as a thermal conductivity enhancer in a carbon foam as a base structure. Two carbon foam materials of low and high values of thermal conductivities, CF20 and KL1-250 (3.1 and 40 W/m K), were tested as a base structure for the TM modules. Tests were conducted at different power intensities and power cycling/loading modes. Results showed that for all power varying modes and all carbon foams, the infiltration of RT65 into carbon foam reduces the temperature of TM module and results in damping the temperature spikes height. Infiltration of MWCNTS into RT65 further improves the effectiveness of TM module. Temperature damping was more pronounced in stand-alone pulsed power cycles as compared to pulsed power spikes modes. The effectiveness of inclusion of RT65 and RT65/MWCNTs in damping the temperature spikes height is remarkable in TM modules based on KL1-250 as compared to CF-20.

A laboratory evaluation of four quality control devices for radiographic processing.

PubMed

Rushton, V E; Horner, K

1994-08-01

Quality assurance programmes for radiographic processing traditionally employ expensive sensitometric and densitometric techniques. However cheap and simple devices for monitoring radiographic processing are available. The aim of this study was to make a comparison of four such devices in terms of their ability to detect variations in radiographic density of clinical significance. Three of the devices are commercially available while the fourth is easily manufactured from waste materials. Ideal bitewing exposure times were selected for four different kilovoltage/film speed combinations. Phantom bitewing radiographs, exposed using these exposure times, were processed using a variety of times and developer temperatures to simulate variations in radiographic quality due to inadequate processing conditions. Test films, produced using the four monitoring devices, were exposed and processed under identical conditions. The phantom bitewings were judged to have 'acceptable' quality when the optical density of that part of the film not showing calcified structures was within +/- 0.5 of that of the film processed under optimal conditions. The efficacy of the monitoring devices in indicating the adequacy of processing was assessed by a comparison of their readings with those made from the phantom bitewings. None of the monitoring devices was ideal for all the kilovoltage/film speed combinations tested, but the homemade device proved to be the most generally effective. We conclude that guidelines to dentists on radiographic quality assurance should include reference to and details of this simple device.

A new device to test cutting efficiency of mechanical endodontic instruments

PubMed Central

Rubini, Alessio Giansiracusa; Plotino, Gianluca; Al-Sudani, Dina; Grande, Nicola M.; Putorti, Ermanno; Sonnino, GianPaolo; Cotti, Elisabetta; Testarelli, Luca; Gambarini, Gianluca

2014-01-01

Background The purpose of the present study was to introduce a new device specifically designed to evaluate the cutting efficiency of mechanically driven endodontic instruments. Material/Methods Twenty new Reciproc R25 (VDW, Munich, Germany) files were used to be investigated in the new device developed to test the cutting ability of endodontic instruments. The device consists of a main frame to which a mobile plastic support for the hand-piece is connected and a stainless-steel block containing a Plexiglas block against which the cutting efficiency of the instruments was tested. The length of the block cut in 1 minute was measured in a computerized program with a precision of 0.1mm. The instruments were activated by using a torque-controlled motor (Silver Reciproc; VDW, Munich, Germany) in a reciprocating movement by the “Reciproc ALL” program (Group 1) and in counter-clockwise rotation at 300 rpm (Group 2). Mean and standard deviations of each group were calculated and data were statistically analyzed with a one-way ANOVA test (P<0.05). Results Reciproc in reciprocation (Group 1) mean cut in the Plexiglas block was 8.6 mm (SD=0.6 mm), while Reciproc in rotation mean cut was 8.9 mm (SD=0.7 mm). There was no statistically significant difference between the 2 groups investigated (P>0.05). Conclusions The cutting testing device evaluated in the present study was reliable and easy to use and may be effectively used to test cutting efficiency of both rotary and reciprocating mechanical endodontic instruments. PMID:24603777

Development of laboratory oxidative aging procedures for asphalt cements and asphalt mixtures.

DOT National Transportation Integrated Search

1986-12-01

An evaluation of an oxidative aging procedure for asphalt materials is described. Test results and the effectiveness of the aging device used are presented. The study was performed by Oregon State University and the Oregon Department of Transportatio...

10 CFR 32.210 - Registration of product information.

Code of Federal Regulations, 2010 CFR

2010-01-01

... sent to the Office of Federal and State Materials and Environmental Management Programs, by an... device must include sufficient information about the design, manufacture, prototype testing, quality... the evaluation, the Commission issues a certificate of registration to the person making the request...

49 CFR 572.71 - General description.

Code of Federal Regulations, 2010 CFR

2010-10-01

... ADMINISTRATION, DEPARTMENT OF TRANSPORTATION (CONTINUED) ANTHROPOMORPHIC TEST DEVICES 6-Year-Old Child § 572.71 General description. (a) The representative 6-year-old dummy consists of a drawings and specifications package that contains the following materials: (1) Technical drawings, specifications, and the parts list...

A Field-Based Cleaning Protocol for Sampling Devices Used in Life-Detection Studies

NASA Astrophysics Data System (ADS)

Eigenbrode, Jennifer; Benning, Liane G.; Maule, Jake; Wainwright, Norm; Steele, Andrew; Amundsen, Hans E. F.

2009-06-01

Analytical approaches to extant and extinct life detection involve molecular detection often at trace levels. Thus, removal of biological materials and other organic molecules from the surfaces of devices used for sampling is essential for ascertaining meaningful results. Organic decontamination to levels consistent with null values on life-detection instruments is particularly challenging at remote field locations where Mars analog field investigations are carried out. Here, we present a seven-step, multi-reagent decontamination method that can be applied to sampling devices while in the field. In situ lipopolysaccharide detection via low-level endotoxin assays and molecular detection via gas chromatography-mass spectrometry were used to test the effectiveness of the decontamination protocol for sampling of glacial ice with a coring device and for sampling of sediments with a rover scoop during deployment at Arctic Mars-analog sites in Svalbard, Norway. Our results indicate that the protocols and detection technique sufficiently remove and detect low levels of molecular constituents necessary for life-detection tests.

A field-based cleaning protocol for sampling devices used in life-detection studies.

PubMed

Eigenbrode, Jennifer; Benning, Liane G; Maule, Jake; Wainwright, Norm; Steele, Andrew; Amundsen, Hans E F

2009-06-01

Analytical approaches to extant and extinct life detection involve molecular detection often at trace levels. Thus, removal of biological materials and other organic molecules from the surfaces of devices used for sampling is essential for ascertaining meaningful results. Organic decontamination to levels consistent with null values on life-detection instruments is particularly challenging at remote field locations where Mars analog field investigations are carried out. Here, we present a seven-step, multi-reagent decontamination method that can be applied to sampling devices while in the field. In situ lipopolysaccharide detection via low-level endotoxin assays and molecular detection via gas chromatography-mass spectrometry were used to test the effectiveness of the decontamination protocol for sampling of glacial ice with a coring device and for sampling of sediments with a rover scoop during deployment at Arctic Mars-analog sites in Svalbard, Norway. Our results indicate that the protocols and detection technique sufficiently remove and detect low levels of molecular constituents necessary for life-detection tests.

Boron carbide coating deposition on tungsten and testing of tungsten layers and coating under intense plasma load

DOE Office of Scientific and Technical Information (OSTI.GOV)

Airapetov, A. A.; Begrambekov, L. B., E-mail: lbb@plasma.mephi.ru; Buzhinskiy, O. I.

2015-12-15

A device intended for boron carbide coating deposition and material testing under high heat loads is presented. A boron carbide coating 5 μm thick was deposited on the tungsten substrate. These samples were subjected to thermocycling loads in the temperature range of 400–1500°C. Tungsten layers deposited on tungsten substrates were tested in similar conditions. Results of the surface analysis are presented.

Combination of Universal Mechanical Testing Machine with Atomic Force Microscope for Materials Research

PubMed Central

Zhong, Jian; He, Dannong

2015-01-01

Surface deformation and fracture processes of materials under external force are important for understanding and developing materials. Here, a combined horizontal universal mechanical testing machine (HUMTM)-atomic force microscope (AFM) system is developed by modifying UMTM to combine with AFM and designing a height-adjustable stabilizing apparatus. Then the combined HUMTM-AFM system is evaluated. Finally, as initial demonstrations, it is applied to analyze the relationship among macroscopic mechanical properties, surface nanomorphological changes under external force, and fracture processes of two kinds of representative large scale thin film materials: polymer material with high strain rate (Parafilm) and metal material with low strain rate (aluminum foil). All the results demonstrate the combined HUMTM-AFM system overcomes several disadvantages of current AFM-combined tensile/compression devices including small load force, incapability for large scale specimens, disability for materials with high strain rate, and etc. Therefore, the combined HUMTM-AFM system is a promising tool for materials research in the future. PMID:26265357

Combination of Universal Mechanical Testing Machine with Atomic Force Microscope for Materials Research.

PubMed

Zhong, Jian; He, Dannong

2015-08-12

Surface deformation and fracture processes of materials under external force are important for understanding and developing materials. Here, a combined horizontal universal mechanical testing machine (HUMTM)-atomic force microscope (AFM) system is developed by modifying UMTM to combine with AFM and designing a height-adjustable stabilizing apparatus. Then the combined HUMTM-AFM system is evaluated. Finally, as initial demonstrations, it is applied to analyze the relationship among macroscopic mechanical properties, surface nanomorphological changes under external force, and fracture processes of two kinds of representative large scale thin film materials: polymer material with high strain rate (Parafilm) and metal material with low strain rate (aluminum foil). All the results demonstrate the combined HUMTM-AFM system overcomes several disadvantages of current AFM-combined tensile/compression devices including small load force, incapability for large scale specimens, disability for materials with high strain rate, and etc. Therefore, the combined HUMTM-AFM system is a promising tool for materials research in the future.

Advanced Modeling of Micromirror Devices

NASA Technical Reports Server (NTRS)

Michalicek, M. Adrian; Sene, Darren E.; Bright, Victor M.

1995-01-01

The flexure-beam micromirror device (FBMD) is a phase only piston style spatial light modulator demonstrating properties which can be used for phase adaptive corrective optics. This paper presents a complete study of a square FBMD, from advanced model development through final device testing and model verification. The model relates the electrical and mechanical properties of the device by equating the electrostatic force of a parallel-plate capacitor with the counter-acting spring force of the device's support flexures. The capacitor solution is derived via the Schwartz-Christoffel transformation such that the final solution accounts for non-ideal electric fields. The complete model describes the behavior of any piston-style device, given its design geometry and material properties. It includes operational parameters such as drive frequency and temperature, as well as fringing effects, mirror surface deformations, and cross-talk from neighboring devices. The steps taken to develop this model can be applied to other micromirrors, such as the cantilever and torsion-beam designs, to produce an advanced model for any given device. The micromirror devices studied in this paper were commercially fabricated in a surface micromachining process. A microscope-based laser interferometer is used to test the device in which a beam reflected from the device modulates a fixed reference beam. The mirror displacement is determined from the relative phase which generates a continuous set of data for each selected position on the mirror surface. Plots of this data describe the localized deflection as a function of drive voltage.

Piezoelectric Bolt Breakers and Bolt Fatigue Testers

NASA Technical Reports Server (NTRS)

Sherrit, Stewart; Badescu, Mircea; Bar-Cohen, Yoseph; Barengoltz, Jack; Heckman, Vanessa

2008-01-01

A proposed family of devices for inducing fatigue in bolts in order to break the bolts would incorporate piezoelectric actuators into resonant fixtures as in ultrasonic/ sonic drills/corers and similar devices described in numerous prior NASA Tech Briefs articles. These devices were originally intended primarily for use as safer, more-reliable, more-versatile alternatives to explosive bolts heretofore used to fasten spacecraft structures that must subsequently be separated from each other quickly on command during flight. On Earth, these devices could be used for accelerated fatigue testing of bolts. Fatigue theory suggests that a bolt subjected to both a constant-amplitude dynamic (that is, oscillatory) stress and a static tensile stress below the ultimate strength of the bolt material will fail faster than will a bolt subjected to only the dynamic stress. This suggestion would be applied in a device of the proposed type. The device would be designed so that the device and the bolt to be fatigue-tested or broken would be integral parts of an assembly (see figure). The static tension in the tightened bolt would apply not only the clamping force to hold the joined structures (if any) together but also the compression necessary for proper operation of the piezoelectric actuators as parts of a resonant structural assembly. The constant-amplitude dynamic stress would be applied to the bolt by driving the piezoelectric actuators with a sinusoidal voltage at the resonance frequency of longitudinal vibration of the assembly. The amplitude of the excitation would be made large enough so that the vibration would induce fatigue in the bolt within an acceptably short time. In the spacecraft applications or in similar terrestrial structural-separation applications, devices of the proposed type would offer several advantages over explosive bolts: Unlike explosive bolts, the proposed devices would be reusable, could be tested before final use, and would not be subject to catastrophic misfire. In fatigue-testing applications, devices of the proposed type would offer advantages of compactness and low cost, relative to conventional fatigue- testing apparatuses. In both structural- separation and fatigue-testing applications, bolts to be broken or tested could be instrumented with additional ultrasonic transducers for monitoring of pertinent physical properties and of fatigue failure processes.

How to qualify and validate wear simulation devices and methods.

PubMed

Heintze, S D

2006-08-01

The clinical significance of increased wear can mainly be attributed to impaired aesthetic appearance and/or functional restrictions. Little is known about the systemic effects of swallowed or inhaled worn particles that derive from restorations. As wear measurements in vivo are complicated and time-consuming, wear simulation devices and methods had been developed without, however, systematically looking at the factors that influence important wear parameters. Wear simulation devices shall simulate processes that occur in the oral cavity during mastication, namely force, force profile, contact time, sliding movement, clearance of worn material, etc. Different devices that use different force actuator principles are available. Those with the highest citation frequency in the literature are - in descending order - the Alabama, ACTA, OHSU, Zurich and MTS wear simulators. When following the FDA guidelines on good laboratory practice (GLP) only the expensive MTS wear simulator is a qualified machine to test wear in vitro; the force exerted by the hydraulic actuator is controlled and regulated during all movements of the stylus. All the other simulators lack control and regulation of force development during dynamic loading of the flat specimens. This may be an explanation for the high coefficient of variation of the results in some wear simulators (28-40%) and the poor reproducibility of wear results if dental databases are searched for wear results of specific dental materials (difference of 22-72% for the same material). As most of the machines are not qualifiable, wear methods applying the machine may have a sound concept but cannot be validated. Only with the MTS method have wear parameters and influencing factors been documented and verified. A good compromise with regard to costs, practicability and robustness is the Willytec chewing simulator, which uses weights as force actuator and step motors for vertical and lateral movements. The Ivoclar wear method run on the Willytec machine shows a mean coefficient of variation in vertical wear of 12%. Force measurements have revealed that in the beginning of the stylus/specimen contact phase the force impulse is 3-4 times higher during dynamic loading than during static loading. When correlating material properties to the wear results of 23 composite resins subjected to the Ivoclar method, some parameters could be identified and incorporated into a wear formula to predict wear with the Ivoclar method. A round robin test evaluating the wear of ten dental materials with five wear simulation methods showed that the results were not comparable, as all methods follow different wear testing concepts. All wear methods lack the evidence of their clinical relevance because prospective studies correlating in vitro with long-term in vivo results with identical materials are not available. For direct restorative materials, amalgam seems to be a realistic reference material. For indirect, namely crown and bridge materials, low strength ceramic is appropriate.

In situ thermomechanical testing methods for micro/nano-scale materials.

PubMed

Kang, Wonmo; Merrill, Marriner; Wheeler, Jeffrey M

2017-02-23

The advance of micro/nanotechnology in energy-harvesting, micropower, electronic devices, and transducers for automobile and aerospace applications has led to the need for accurate thermomechanical characterization of micro/nano-scale materials to ensure their reliability and performance. This persistent need has driven various efforts to develop innovative experimental techniques that overcome the critical challenges associated with precise mechanical and thermal control of micro/nano-scale specimens during material characterization. Here we review recent progress in the development of thermomechanical testing methods from miniaturized versions of conventional macroscopic test systems to the current state of the art of in situ uniaxial testing capabilities in electron microscopes utilizing either indentation-based microcompression or integrated microsystems. We discuss the major advantages/disadvantages of these methods with respect to specimen size, range of temperature control, ease of experimentation and resolution of the measurements. We also identify key challenges in each method. Finally, we summarize some of the important discoveries that have been made using in situ thermomechanical testing and the exciting research opportunities still to come in micro/nano-scale materials.

Design, fabrication and test of prototype furnace for continuous growth of wide silicon ribbon

NASA Technical Reports Server (NTRS)

Duncan, C. S.; Seidensticker, R. G.

1976-01-01

A program having the overall objective of growing wide, thin silicon dendritic web crystals quasi-continuously from a semi-automated facility is discussed. The design considerations and fabrication of the facility as well as the test and operation phase are covered; detailed engineering drawings are included as an appendix. During the test and operation phase of the program, more than eighty growth runs and numerous thermal test runs were performed. At the conclusion of the program, 2.4 cm wide web was being grown at thicknesses of 100 to 300 micrometers. As expected, the thickness and growth rate are closely related. Solar cells made from this material were tested at NASA-Lewis and found to have conversion efficiencies comparable to devices fabricated from Czochralski material.

Thermic sealing in femoral catheterisation: First experience with the Secure Device.

PubMed

Sacherer, Michael; Kolesnik, Ewald; von Lewinski, Friederike; Verheyen, Nicolas; Brandner, Karin; Wallner, Markus; Eaton, Deborah M; Luha, Olev; Zweiker, Robert; von Lewinski, Dirk

2018-04-03

Devices currently used to achieve hemostasis of the femoral artery following percutaneous cardiac catheterization are associated with vascular complications and remnants of artificial materials are retained at the puncture site. The SECURE arterial closure device induces hemostasis by utilizing thermal energy, which causes collagen shrinking and swelling. In comparison to established devices, it has the advantage of leaving no foreign material in the body following closing. This study was designed to evaluate the efficacy and safety of the SECURE device to close the puncture site following percutaneous cardiac catheterization. The SECURE device was evaluated in a prospective non-randomized single-centre trial with patients undergoing 6 F invasive cardiac procedures. A total of 67 patients were enrolled and the device was utilized in 63 patients. 50 diagnostic and 13 interventional cases were evaluated. Femoral artery puncture closure was performed immediately after completion of the procedure. Time to hemostasis (TTH), time to ambulation (TTA) and data regarding short-term and 30-day clinical follow-up were recorded. Mean TTH was 4:30 ± 2:15 min in the overall observational group. A subpopulation of patients receiving anticoagulants had a TTH of 4:53 ± 1:43 min. There were two access site complications (hematoma > 5 cm). No major adverse events were identified during hospitalization or at the 30 day follow-up. The new SECURE device demonstrates that it is feasible in diagnostic and interventional cardiac catheterization. With respect to safety, the SECURE device was non-inferior to other closure devices as tested in the ISAR closure trial.

Design and development of a bio-inspired, under-actuated soft gripper.

PubMed

Hassan, Taimoor; Manti, Mariangela; Passetti, Giovanni; d'Elia, Nicolò; Cianchetti, Matteo; Laschi, Cecilia

2015-08-01

The development of robotic devices able to perform manipulation tasks mimicking the human hand has been assessed on large scale. This work stands in the challenging scenario where soft materials are combined with bio-inspired design in order to develop soft grippers with improved grasping and holding capabilities. We are going to show a low-cost, under-actuated and adaptable soft gripper, highlighting the design and the manufacturing process. In particular, a critical analysis is made among three versions of the gripper with same design and actuation mechanism, but based on different materials. A novel actuation principle has been implemented in both cases, in order to reduce the encumbrance of the entire system and improve its aesthetics. Grasping and holding capabilities have been tested for each device, with target objects varying in shape, size and material. Results highlight synergy between the geometry and the intrinsic properties of the soft material, showing the way to novel design principles for soft grippers.

Anomalous acoustic dispersion in architected microlattice metamaterials

NASA Astrophysics Data System (ADS)

KröDel, Sebastian; Palermo, Antonio; Daraio, Chiara

The ability to control dispersion in acoustic metamaterials is crucial to realize acoustic filtering and rectification devices as well as perfect imaging using negative refractive index materials. Architected microlattice metamaterials immersed in fluid constitute a versatile platform for achieving such control. We investigate architected microlattice materials able to exploit locally resonant modes of their fundamental building blocks that couple with propagating acoustic waves. Using analytical, numerical and experimental methods we find that such lattice materials show a hybrid dispersion behavior governed by Biot's theory for long wavelengths and multiple scattering theory when wave frequency is close to the resonances of the building block. We identify the relevant geometric parameters to alter and control the group and phase velocities in this class of acoustic metamaterials. Furthermore, we fabricate small-scale acoustic metamaterial samples using high precision SLA additive manufacturing and test the resulting materials experimentally using a customized ultrasonic setup. This work paves the way for new acoustic devices based on microlattice metamaterials.

Encapsulation methods for organic electrical devices

DOEpatents

Blum, Yigal D.; Chu, William Siu-Keung; MacQueen, David Brent; Shi, Yijian

2013-06-18

The disclosure provides methods and materials suitable for use as encapsulation barriers in electronic devices. In one embodiment, for example, there is provided an electroluminescent device or other electronic device encapsulated by alternating layers of a silicon-containing bonding material and a ceramic material. The encapsulation methods provide, for example, electronic devices with increased stability and shelf-life. The invention is useful, for example, in the field of microelectronic devices.

Material Damping Experiments at Cryogenic Temperatures

NASA Technical Reports Server (NTRS)

Levine, Marie; White, Christopher

2003-01-01

A unique experimental facility has been designed to measure damping of materials at cryogenic temperatures. The test facility pays special attention to removing other sources of damping in the measurement by avoiding frictional interfaces, decoupling the test specimen from the support system, and by using a non-contacting measurement device; Damping data is obtained for materials (AI, GrEp, Be, Fused Quartz), strain amplitudes (less than 10-6 ppm), frequencies (20Hz-330Hz) and temperatures (20K-293K) relevant to future precision optical space missions. The test data shows a significant decrease in viscous damping at cryogenic temperatures and can be as low as 10-4%, but the amount of the damping decrease is a function of frequency and material. Contrary to the other materials whose damping monotonically decreased with temperature, damping of Fused Quartz increased substantially at cryo, after reaching a minimum at around l50 K. The damping is also shown to be insensitive to strain for low strain levels. At room temperatures, the test data correlates well to the analytical predictions of the Zener damping model. Discrepancies at cryogenic temperatures between the model predictions and the test data are observed.

An Assessment of the Current Day Impact of Various Materials Associated with the U.S. Nuclear Test Program in the Marshall Island

DOE Office of Scientific and Technical Information (OSTI.GOV)

Robison, W L; Noshkin, V E; Hamilton, T F

2001-05-01

Different stable elements, and some natural and man-made radionuclides, were used as tracers or associated in other ways with nuclear devices that were detonated at Bikini and Enewetak Atolls as part of the U.S. nuclear testing program from 1946 through 1958. The question has been raised whether any of these materials dispersed by the explosions could be of sufficient concentration in either the marine environment or on the coral islands to be of a health concern to people living, or planning to live, on the atolls. This report addresses that concern. An inventory of the materials involved during the testmore » period was prepared and provided to us by the Office of Defense Programs (DP) of the United States Department of Energy (DOE). The materials that the DOE and the Republic of the Marshall Islands (RMI) ask to be evaluated are--sulfur, arsenic, yttrium, tantalum, gold, rhodium, indium, tungsten, thallium, thorium-230,232 ({sup 230,232}Th), uranium-233,238 ({sup 233,238}U), polonium-210 ({sup 210}Po), curium-232 ({sup 232}Cu), and americium-241 ({sup 241}Am). The stable elements were used primarily as tracers for determining neutron energy and flux, and for other diagnostic purposes in the larger yield, multistage devices. It is reasonable to assume that these materials would be distributed in a similar manner as the fission products subsequent to detonation. A large inventory of fission product and uranium data was available for assessment. Detailed calculations show only a very small fraction of the fission products produced during the entire test series remain at the test site atolls. Consequently, based on the information provided, we conclude that the concentration of these materials in the atoll environment pose no adverse health effects to humans.« less

Detection of vehicle-based improvised explosives using ultra-trace detection equipment

NASA Astrophysics Data System (ADS)

Fisher, Mark; Sikes, John; Prather, Mark; Wichert, Clint

2005-05-01

Vehicle-borne improvised explosive devices (VBIEDs) have become the weapon of choice for insurgents in Iraq. At the same time, these devices are becoming increasingly sophisticated and effective. VBIEDs can be difficult to detect during visual inspection of vehicles. This is especially true when explosives have been hidden behind a vehicle"s panels, inside seat cushions, under floorboards, or behind cargo. Even though the explosive may not be visible, vapors of explosive emanating from the device are often present in the vehicle, but the current generation of trace detection equipment has not been sensitive enough to detect these low concentrations of vapor. This paper presents initial test results using the Nomadics Fido sensor for detection of VBIEDs. The sensor is a small, explosives detector with unprecedented levels of sensitivity for detection of nitroaromatic explosives. Fido utilizes fluorescence quenching of novel polymer materials to detect traces of explosive vapor emanating from targets containing explosives. These materials, developed by collaborators at the Massachusetts Institute of Technology (MIT), amplify the quenching response that occurs when molecules of explosive bind to films of the polymer. These materials have enabled development of sensors with performance approaching that of canines trained to detect explosives. The ability of the sensor to detect explosives in vehicles and on persons who have recently been in close proximity to explosives has recently been demonstrated. In these tests, simulated targets were quickly and easily detected using a Fido sensor in conjunction with both direct vapor and swipe sampling methods. The results of these tests suggest that chemical vapor sensing has utility as a means of screening vehicles for explosives at checkpoints and on patrols.

Empirical study of alginate impression materials by customized proportioning system

PubMed Central

2016-01-01

PURPOSE Alginate mixers available in the market do not have the automatic proportioning unit. In this study, an automatic proportioning unit for the alginate mixer and controller software were designed and produced for a new automatic proportioning unit. With this device, it was ensured that proportioning operation could arrange weight-based alginate impression materials. MATERIALS AND METHODS The variation of coefficient in the tested groups was compared with the manual proportioning. Compression tension and tear tests were conducted to determine the mechanical properties of alginate impression materials. The experimental data were statistically analyzed using one way ANOVA and Tukey test at the 0.05 level of significance. RESULTS No statistically significant differences in modulus of elastisity (P>0.3), tensional/compresional strength (P>0.3), resilience (P>0.2), strain in failure (P>0.4), and tear energy (P>0.7) of alginate impression materials were seen. However, a decrease in the standard deviation of tested groups was observed when the customized machine was used. To verify the efficiency of the system, powder and powder/water mixing were weighed and significant decrease was observed. CONCLUSION It was possible to obtain more mechanically stable alginate impression materials by using the custom-made proportioning unit. PMID:27826387

Microfluidic devices for stem-cell cultivation, differentiation and toxicity testing

NASA Astrophysics Data System (ADS)

Becker, Holger; Hansen-Hagge, Thomas; Kurtz, Andreas; Mrowka, Ralf; Wölfl, Stefan; Gärtner, Claudia

2017-02-01

The development of new drugs is time-consuming, extremely expensive and often promising drug candidates fail in late stages of the development process due to the lack of suitable tools to either predict toxicological effects or to test drug candidates in physiologically relevant environments prior to clinical tests. We therefore try to develop diagnostic multiorgan microfluidic chips based on patient specific induced pluripotent stem cell (iPS) technology to explore liver dependent toxic effects of drugs on individual human tissues such as liver or kidney cells. Based initially on standardized microfluidic modules for cell culture, we have developed integrated microfluidic devices which contain different chambers for cell/tissue cultivation. The devices are manufactured using injection molding of thermoplastic polymers such as polystyrene or cyclo-olefin polymer. In the project, suitable surface modification methods of the used materials had to be explored. We have been able to successfully demonstrate the seeding, cultivation and further differentiation of modified iPS, as shown by the use of differentiation markers, thus providing a suitable platform for toxicity testing and potential tissue-tissue interactions.

Robust broad spectral photodetection (UV-NIR) and ultra high responsivity investigated in nanosheets and nanowires of Bi2Te3 under harsh nano-milling conditions.

PubMed

Sharma, Alka; Srivastava, A K; Senguttuvan, T D; Husale, Sudhir

2017-12-20

Due to miniaturization of device dimensions, the next generation's photodetector based devices are expected to be fabricated from robust nanostructured materials. Hence there is an utmost requirement of investigating exotic optoelectronic properties of nanodevices fabricated from new novel materials and testing their performances at harsh conditions. The recent advances on 2D layered materials indicate exciting progress on broad spectral photodetection (BSP) but still there is a great demand for fabricating ultra-high performance photodetectors made from single material sensing broad electromagnetic spectrum since the detection range 325 nm-1550 nm is not covered by the conventional Si or InGaAs photodetectors. Alternatively, Bi 2 Te 3 is a layered material, possesses exciting optoelectronic, thermoelectric, plasmonics properties. Here we report robust photoconductivity measurements on Bi 2 Te 3 nanosheets and nanowires demonstrating BSP from UV to NIR. The nanosheets of Bi 2 Te 3 show the best ultra-high photoresponsivity (~74 A/W at 1550 nm). Further these nanosheets when transform into nanowires using harsh FIB milling conditions exhibit about one order enhancement in the photoresponsivity without affecting the performance of the device even after 4 months of storage at ambient conditions. An ultra-high photoresponsivity and BSP indicate exciting robust nature of topological insulator based nanodevices for optoelectronic applications.

Paper-polymer composite devices with minimal fluorescence background.

PubMed

Wang, Chang-Ming; Chen, Chong-You; Liao, Wei-Ssu

2017-04-22

Polymer film incorporated paper-based devices show advantages in simplicity and rugged backing. However, their applications are restricted by the high fluorescence background interference of conventional laminating pouches. Herein, we report a straightforward approach for minimal fluorescence background device fabrication, in which filter paper was shaped and laminated in between two biaxially oriented polypropylene (OPP) and polyvinyl butyral (PVB) composite films. This composite film provides mechanical strength for enhanced device durability, protection from environmental contamination, and prevents reagent degradation. This approach was tested by the determination of copper ions with a fluorescent probe, while the detection of glucose was used to illustrate the improved device durability. Our results show that lamination by the polymer composite lengthens device lifetime, while allowing for fluorescence detection methods combination with greatly reduced fluorescent background widely present in commercially available lamination pouches. By the combination of rapid device prototyping with low cost materials, we believe that this composite design would further expand the potential of paper-based devices. Copyright © 2017 Elsevier B.V. All rights reserved.

1-dimension nano-material-based flexible device

NASA Astrophysics Data System (ADS)

Yang, Xing; Zhou, Zhaoying; Zheng, Fuzhong

2009-11-01

1D nano-material-based flexible devices has attracted considerable attention owing to the growing need of the high-sensitivity flexible sensor, portable consumer electronics etc.. In this paper, the 1D nano-materials-based flexible device on polyimide substrate was proposed. The bottom-up and top-down combined process were used for constructing the ZnO nanowire and the CNT-based flexible devices. Their electrical characteristics were also investigated. The measurement results demonstrate that the flexible device covered with a layer of Al2O3 has good ohm electrical contact behavior between the nano-material and micro-electrodes. The proposed 1D nano-material-based flexible device shows the application potential in the sensing fields.

Novel hole transport materials for organic light emitting devices

NASA Astrophysics Data System (ADS)

Shi, Jianmin; Forsythe, Eric; Morton, David

2008-08-01

Organic electronic devices generally have a layered structure with organic materials sandwiched between an anode and a cathode, such organic electronic devices of organic light-emitting diode (OLED), organic photovoltaic (OPV), organic thin-film transistor (OTFT). There are many advantages of these organic electronic devices as compared to silicon-based devices. However, one of key challenge for an organic electronic device is to minimize the charge injection barrier from electrodes to organic materials and improve the charge transport mobility. In order to overcome these circumstances, there are many approaches including, designing organic materials with minimum energy barriers and improving charge transport mobility. Ideally organic materials or complex with Ohmic contact will be the most desired.

Synthesis of graphene and related two-dimensional materials for bioelectronics devices.

PubMed

Zhang, Tao; Liu, Jilun; Wang, Cheng; Leng, Xuanye; Xiao, Yao; Fu, Lei

2017-03-15

In recent years, graphene and related two-dimensional (2D) materials have emerged as exotic materials in nearly every fields of fundamental science and applied engineering. The latest progress has shown that these 2D materials could have a profound impact on bioelectronics devices. For the construction of these bioelectronics devices, these 2D materials were generally synthesized by the processes of exfoliation and chemical vapor deposition. In particular, the macrostructures of these 2D materials have also been realized by these two processes, which have shown great potentials in the self-supported and special-purpose biosensors. Due to the high specific surface area, subtle electron properties, abundant surface atoms of these 2D materials, the as-constructed bioelectronics devices have exhibited enhanced performance in the sensing of small biomolecules, heavy metals, pH, protein and DNA. The aim of this review article is to provide a comprehensive scientific progress in the synthesis of 2D materials for the construction of five typical bioelectronics devices (electrochemical biosensors, FET-based biosensors, piezoelectric devices, electrochemiluminescence devices and supercapacitors) and to overview the present status and future perspective of the applications of these bioelectronics devices based on 2D materials. Copyright © 2016 Elsevier B.V. All rights reserved.

Energy harvesting: an integrated view of materials, devices and applications.

PubMed

Radousky, H B; Liang, H

2012-12-21

Energy harvesting refers to the set of processes by which useful energy is captured from waste, environmental, or mechanical sources and is converted into a usable form. The discipline of energy harvesting is a broad topic that includes established methods and materials such as photovoltaics and thermoelectrics, as well as more recent technologies that convert mechanical energy, magnetic energy and waste heat to electricity. This article will review various state-of-the-art materials and devices for direct energy conversion and in particular will include multistep energy conversion approaches. The article will highlight the nano-materials science underlying energy harvesting principles and devices, but also include more traditional bulk processes and devices as appropriate and synergistic. Emphasis is placed on device-design innovations that lead to higher efficiency energy harvesting or conversion technologies ranging from the cm/mm-scale down to MEMS/NEMS (micro- and nano-electromechanical systems) devices. Theoretical studies are reviewed, which address transport properties, crystal chemistry, thermodynamic analysis, energy transfer, system efficiency and device operation. New developments in experimental methods; device design and fabrication; nanostructured materials fabrication; materials properties; and device performance measurement techniques are discussed.

Energy harvesting: an integrated view of materials, devices and applications

NASA Astrophysics Data System (ADS)

Radousky, H. B.; Liang, H.

2012-12-01

Energy harvesting refers to the set of processes by which useful energy is captured from waste, environmental, or mechanical sources and is converted into a usable form. The discipline of energy harvesting is a broad topic that includes established methods and materials such as photovoltaics and thermoelectrics, as well as more recent technologies that convert mechanical energy, magnetic energy and waste heat to electricity. This article will review various state-of-the-art materials and devices for direct energy conversion and in particular will include multistep energy conversion approaches. The article will highlight the nano-materials science underlying energy harvesting principles and devices, but also include more traditional bulk processes and devices as appropriate and synergistic. Emphasis is placed on device-design innovations that lead to higher efficiency energy harvesting or conversion technologies ranging from the cm/mm-scale down to MEMS/NEMS (micro- and nano-electromechanical systems) devices. Theoretical studies are reviewed, which address transport properties, crystal chemistry, thermodynamic analysis, energy transfer, system efficiency and device operation. New developments in experimental methods; device design and fabrication; nanostructured materials fabrication; materials properties; and device performance measurement techniques are discussed.

Heat flux sensor research and development: The cool film calorimeter

NASA Technical Reports Server (NTRS)

Abtahi, A.; Dean, P.

1990-01-01

The goal was to meet the measurement requirement of the NASP program for a gauge capable of measuring heat flux into a 'typical' structure in a 'typical' hypersonic flight environment. A device is conceptually described that has fast response times and is small enough to fit in leading edge or cowl lip structures. The device relies heavily on thin film technology. The main conclusion is the description of the limitations of thin film technology both in the art of fabrication and in the assumption that thin films have the same material properties as the original bulk material. Three gauges were designed and fabricated. Thin film deposition processes were evaluated. The effect of different thin film materials on the performance and fabrication of the gauge was studied. The gauges were tested in an arcjet facility. Survivability and accuracy were determined under various hostile environment conditions.

DOE Office of Scientific and Technical Information (OSTI.GOV)

Kuharik, J.; Madrak, R.; Makarov, A.

A second harmonic tunable RF cavity is being devel-oped for the Fermilab Booster. This device, which prom-ises reduction of the particle beam loss at the injection, transition, and extraction stages, employs perpendicularly biased garnet material for frequency tuning. The required range of the tuning is significantly wider than in previously built and tested tunable RF devices. As a result, the mag-netic field in the garnet comes fairly close to the gyromag-netic resonance line at the lower end of the frequency range. The chosen design concept of a tuner for the cavity cannot ensure uniform magnetic field in the garnet mate-rial;more » thus, it is important to know the static magnetic prop-erties of the material to avoid significant increase in the lo-cal RF loss power density. This report summarizes studies performed at Fermilab to understand variations in the mag-netic properties of the AL800 garnet material used to build the tuner of the cavity.« less

Synthesis Methods, Microscopy Characterization and Device Integration of Nanoscale Metal Oxide Semiconductors for Gas Sensing

PubMed Central

Vander Wal, Randy L.; Berger, Gordon M.; Kulis, Michael J.; Hunter, Gary W.; Xu, Jennifer C.; Evans, Laura

2009-01-01

A comparison is made between SnO2, ZnO, and TiO2 single-crystal nanowires and SnO2 polycrystalline nanofibers for gas sensing. Both nanostructures possess a one-dimensional morphology. Different synthesis methods are used to produce these materials: thermal evaporation-condensation (TEC), controlled oxidation, and electrospinning. Advantages and limitations of each technique are listed. Practical issues associated with harvesting, purification, and integration of these materials into sensing devices are detailed. For comparison to the nascent form, these sensing materials are surface coated with Pd and Pt nanoparticles. Gas sensing tests, with respect to H2, are conducted at ambient and elevated temperatures. Comparative normalized responses and time constants for the catalyst and noncatalyst systems provide a basis for identification of the superior metal-oxide nanostructure and catalyst combination. With temperature-dependent data, Arrhenius analyses are made to determine activation energies for the catalyst-assisted systems. PMID:22408484

Fabrication of flexible, multimodal light-emitting devices for wireless optogenetics

PubMed Central

Huang, Xian; Jung, Yei Hwan; Al-Hasani, Ream; Omenetto, Fiorenzo G.

2014-01-01

Summary The rise of optogenetics provides unique opportunities to advance materials and biomedical engineering as well as fundamental understanding in neuroscience. This protocol describes the fabrication of optoelectronic devices for studying intact neural systems. Unlike optogenetic approaches that rely on rigid fiber optics tethered to external light sources, these novel devices utilize flexible substrates to carry wirelessly powered microscale, inorganic light-emitting diodes (μ-ILEDs) and multimodal sensors inside the brain. We describe the technical procedures for construction of these devices, their corresponding radiofrequency power scavengers, and their implementation in vivo for experimental application. In total, the timeline of the procedure, including device fabrication, implantation, and preparation to begin in vivo experimentation, can be completed in approximately 3–8 weeks. Implementation of these devices allows for chronic (tested up to six months), wireless optogenetic manipulation of neural circuitry in animals experiencing behaviors such as social interaction, home cage, and other complex natural environments. PMID:24202555

Non- contacting capacitive diagnostic device

DOEpatents

Ellison, Timothy

2005-07-12

A non-contacting capacitive diagnostic device includes a pulsed light source for producing an electric field in a semiconductor or photovoltaic device or material to be evaluated and a circuit responsive to the electric field. The circuit is not in physical contact with the device or material being evaluated and produces an electrical signal characteristic of the electric field produced in the device or material. The diagnostic device permits quality control and evaluation of semiconductor or photovoltaic device properties in continuous manufacturing processes.

Grips for testing of electrical characteristics of a specimen under a mechanical load

DOE Office of Scientific and Technical Information (OSTI.GOV)

Briggs, Timothy; Loyola, Bryan

Various technologies to facilitate coupled electrical and mechanical measurement of conductive materials are disclosed herein. A gripping device simultaneously holds a specimen in place and causes contact to be made between the specimen and a plurality of electrodes connected to an electrical measuring device. An electrical characteristic of the specimen is then measured while a mechanical load is applied to the specimen, and a relationship between the mechanical load and changes in the electrical characteristic can be identified.

Nonlinear Properties in Langasite Isomorphs for Advanced Frequency Control Devices and Clocks

DTIC Science & Technology

2006-11-01

or LGN), and langatate (La3Ga5.5Ta0.5O14 or LGT), have emerged as new materials to replace quartz in advanced frequency control devices and clocks...application and of angle Ψ. Fig. 1. Langatate boule (photo courtesy of the Univ. Central Florida) and typical resonators for testing. Table 1...langanite and y-cut langatate ,” IEEE Tr. Ultrason. Ferroelec. Freq. Contr., pp. 1678-1682, 2003. Kim, Y., “Amplitude-frequency effect of Y-cut langanite

Custom fabrication of biomass containment devices using 3-D printing enables bacterial growth analyses with complex insoluble substrates

DOE Office of Scientific and Technical Information (OSTI.GOV)

Nelson, Cassandra E.; Beri, Nina R.; Gardner, Jeffrey G.

Physiological studies of recalcitrant polysaccharide degradation are challenging for several reasons, one of which is the difficulty in obtaining a reproducibly accurate real-time measurement of bacterial growth using insoluble substrates. Current methods suffer from several problems including (i) high background noise due to the insoluble material interspersed with cells, (ii) high consumable and reagent cost and (iii) significant time delay between sampling and data acquisition. A customizable substrate and cell separation device would provide an option to study bacterial growth using optical density measurements. To test this hypothesis we used 3-D printing to create biomass containment devices that allow interactionmore » between insoluble substrates and microbial cells but do not interfere with spectrophotometer measurements. Evaluation of materials available for 3-D printing indicated that UV-cured acrylic plastic was the best material, being superior to nylon or stainless steel when examined for heat tolerance, reactivity, and ability to be sterilized. Cost analysis of the 3-D printed devices indicated they are a competitive way to quantitate bacterial growth compared to viable cell counting or protein measurements, and experimental conditions were scalable over a 100-fold range. The presence of the devices did not alter growth phenotypes when using either soluble substrates or insoluble substrates. Furthermore, we applied biomass containment to characterize growth of Cellvibrio japonicus on authentic lignocellulose (non-pretreated corn stover), and found physiological evidence that xylan is a significant nutritional source despite an abundance of cellulose present.« less

Custom fabrication of biomass containment devices using 3-D printing enables bacterial growth analyses with complex insoluble substrates

DOE PAGES

Nelson, Cassandra E.; Beri, Nina R.; Gardner, Jeffrey G.

2016-09-21

Physiological studies of recalcitrant polysaccharide degradation are challenging for several reasons, one of which is the difficulty in obtaining a reproducibly accurate real-time measurement of bacterial growth using insoluble substrates. Current methods suffer from several problems including (i) high background noise due to the insoluble material interspersed with cells, (ii) high consumable and reagent cost and (iii) significant time delay between sampling and data acquisition. A customizable substrate and cell separation device would provide an option to study bacterial growth using optical density measurements. To test this hypothesis we used 3-D printing to create biomass containment devices that allow interactionmore » between insoluble substrates and microbial cells but do not interfere with spectrophotometer measurements. Evaluation of materials available for 3-D printing indicated that UV-cured acrylic plastic was the best material, being superior to nylon or stainless steel when examined for heat tolerance, reactivity, and ability to be sterilized. Cost analysis of the 3-D printed devices indicated they are a competitive way to quantitate bacterial growth compared to viable cell counting or protein measurements, and experimental conditions were scalable over a 100-fold range. The presence of the devices did not alter growth phenotypes when using either soluble substrates or insoluble substrates. Furthermore, we applied biomass containment to characterize growth of Cellvibrio japonicus on authentic lignocellulose (non-pretreated corn stover), and found physiological evidence that xylan is a significant nutritional source despite an abundance of cellulose present.« less

Vapor Annealing Controlled Crystal Growth and Photovoltaic Performance of Bismuth Triiodide Embedded in Mesostructured Configurations.

PubMed

Kulkarni, Ashish; Singh, Trilok; Jena, Ajay K; Pinpithak, Peerathat; Ikegami, Masashi; Miyasaka, Tsutomu

2018-03-21

Low stability of organic-inorganic lead halide perovskite and toxicity of lead (Pb) still remain a concern. Therefore, there is a constant quest for alternative nontoxic and stable light-absorbing materials with promising optoelectronic properties. Herein, we report about nontoxic bismuth triiodide (BiI 3 ) photovoltaic device prepared using TiO 2 mesoporous film and spiro-OMeTAD as electron- and hole-transporting materials, respectively. Effect of annealing methods (e.g., thermal annealing (TA), solvent vapor annealing (SVA), and Petri dish covered recycled vapor annealing (PR-VA)) and different annealing temperatures (90, 120, 150, and 180 °C for PR-VA) on BiI 3 film morphology have been investigated. As found in the study, grain size increased and film uniformity improved as temperature was raised from 90 to 150 °C. The photovoltaic devices based on BiI 3 films processed at 150 °C with PR-VA treatment showed power conversion efficiency (PCE) of 0.5% with high reproducibility, which is, so far, the best PCE reported for BiI 3 photovoltaic device employing organic hole-transporting material (HTM), owing to the increase in grain size and uniform morphology of BiI 3 film. These devices showed stable performance even after 30 days of exposure to 50% relative humidity, and after 100 °C heat stress and 20 min light soaking test. More importantly, the study reveals many challenges and room (discussed in the details) for further development of the BiI 3 photovoltaic devices.

Polymer materials and component evaluation in acidic-radiation environments

NASA Astrophysics Data System (ADS)

Celina, M.; Gillen, K. T.; Malone, G. M.; Clough, R. L.; Nelson, W. H.

2001-07-01

Polymeric materials used for cable/wire insulation, electrical connectors, O-rings, seals, and in critical components such as motors, level switches and resistive thermo-devices were evaluated under accelerated degradation conditions in combined radiation-oxidative elevated-temperature acidic-vapor (nitric/oxalic) environments relevant to conditions in isotope processing facilities. Experiments included the assessment of individual materials such as PEEK, polyimides, polyolefin based cable insulation, EPDM rubbers, various epoxy systems, commercial caulking materials as well as some functional testing of components. We discuss how to conduct laboratory experiments to simulate such complex hostile environments, describe some degradation effects encountered, and evaluate the impact on appropriate material and component selection.

Program for the development of high temperature electrical materials and components

NASA Technical Reports Server (NTRS)

Neff, W. S.; Lowry, L. R.

1972-01-01

Evaluation of high temperature, space-vacuum performance of selected electrical materials and components, high temperature capacitor development, and evaluation, construction, and endurance testing of compression sealed pyrolytic boron nitride slot insulation are described. The first subject above covered the aging evaluation of electrical devices constructed from selected electrical materials. Individual materials performances were also evaluated and reported. The second subject included study of methods of improving electrical performance of pyrolytic boron nitride capacitors. The third portion was conducted to evaluate the thermal and electrical performance of pyrolytic boron nitride as stator slot liner material under varied temperature and compressive loading. Conclusions and recommendations are presented.

A new device for performing reference point indentation without a reference probe

NASA Astrophysics Data System (ADS)

Bridges, Daniel; Randall, Connor; Hansma, Paul K.

2012-04-01

Here we describe a novel, hand-held reference point indentation (RPI), instrument that is designed for clinical measurements of bone material properties in living patients. This instrument differs from previous RPI instruments in that it requires neither a reference probe nor removal of the periosteum that covers the bone, thus significantly simplifying its use in patient testing. After describing the instrument, we discuss five guidelines for optimal and reproducible results. These are: (1) the angle between the normal to the surface and the axis of the instrument should be less than 10°, (2) the compression of the main spring to trigger the device must be performed slowly (>1 s), (3) the probe tip should be sharper than 10 μm; however, a normalized parameter with a calibration phantom can correct for dull tips up to a 100 μm radius, (4) the ambient room temperature should be between 4 °C and 37 °C, and (5) the effective mass of the bone or material under test must exceed 1 kg, or if under 1 kg, the specimen should be securely anchored in a fixation device with sufficient mass (which is not a requirement of previous RPI instruments). Our experience is that a person can be trained with these guidelines in about 5 min and thereafter obtain accurate and reproducible results. The portability, ease of use, and minimal training make this instrument suitable to measure bone material properties in a clinical setting.

Micro-field evoked potentials recorded from the porcine sub-dural cortical surface utilizing a microelectrode array.

PubMed

Kitzmiller, Joseph P; Hansford, Derek J; Fortin, Linda D; Obrietan, Karl H; Bergdall, Valerie K; Beversdorf, David Q

2007-05-15

A sub-dural surface microelectrode array designed to detect micro-field evoked potentials has been developed. The device is comprised of an array of 350-microm square gold contacts, with bidirectional spacing of 150 microm, contained within a polyimide Kapton material. Cytotoxicity testing suggests that the device is suitable for use with animal and human patients. Implementation of the device in animal studies revealed that reliable evoked potentials could be acquired. Further work will be needed to determine how these micro-field potentials, which demonstrate selectivity for one eye, relate to the distribution of the ocular dominance columns of the occipital cortex.

Micro-Field Evoked Potentials Recorded from the Porcine Sub-Dural Cortical Surface Utilizing a Microelectrode Array

PubMed Central

Kitzmiller, Joseph P.; Hansford, Derek J.; Fortin, Linda D.; Obrietan, Karl H.; Bergdall, Valerie K.

2007-01-01

A sub-dural surface microelectrode array designed to detect microfield evoked potentials has been developed. The device is comprised of an array of 350-micron square gold contacts, with bi-directional spacing of 150 microns, contained within a polyimide Kapton material. Cytotoxicity testing suggests that the device is suitable for use with animal and human patients. Implementation of the device in animal studies revealed that reliable evoked potentials could be acquired. Further work will be needed to determine how these microfield potentials, which demonstrate selectivity for one eye, relate to the distribution of the ocular dominance columns of the occipital cortex. PMID:17298849

Threat detection in desert environment with passive millimeter-wave sensor

NASA Astrophysics Data System (ADS)

Wilson, John P.; Schuetz, Christopher A.; Martin, Richard D.; Dillon, Thomas E.; Murakowski, Maciej; Prather, Dennis W.

2011-06-01

A new technique for improvised explosive device (IED) creation uses an explosive device buried in foam and covered in a layer of dirt. These devices are difficult to detect visually, however, their material characteristics make them detectable by passive millimeter-wave (pmmW) sensors. Results are presented from a test using a mock IED and an outdoor set-up consisting of two mock IEDs on a dirt background. The results show that the mock IEDs produces a millimeter-wave signature which is distinguishable from the background surrounding the mock IEDs. Simulations based on the measured data are presented and a design for a future vehicle mounted sensor is shown.

Photonics and optoelectronics of two-dimensional materials beyond graphene.

PubMed

Ponraj, Joice Sophia; Xu, Zai-Quan; Dhanabalan, Sathish Chander; Mu, Haoran; Wang, Yusheng; Yuan, Jian; Li, Pengfei; Thakur, Siddharatha; Ashrafi, Mursal; Mccoubrey, Kenneth; Zhang, Yupeng; Li, Shaojuan; Zhang, Han; Bao, Qiaoliang

2016-11-18

Apart from conventional materials, the study of two-dimensional (2D) materials has emerged as a significant field of study for a variety of applications. Graphene-like 2D materials are important elements of potential optoelectronics applications due to their exceptional electronic and optical properties. The processing of these materials towards the realization of devices has been one of the main motivations for the recent development of photonics and optoelectronics. The recent progress in photonic devices based on graphene-like 2D materials, especially topological insulators (TIs) and transition metal dichalcogenides (TMDs) with the methodology level discussions from the viewpoint of state-of-the-art designs in device geometry and materials are detailed in this review. We have started the article with an overview of the electronic properties and continued by highlighting their linear and nonlinear optical properties. The production of TIs and TMDs by different methods is detailed. The following main applications focused towards device fabrication are elaborated: (1) photodetectors, (2) photovoltaic devices, (3) light-emitting devices, (4) flexible devices and (5) laser applications. The possibility of employing these 2D materials in different fields is also suggested based on their properties in the prospective part. This review will not only greatly complement the detailed knowledge of the device physics of these materials, but also provide contemporary perception for the researchers who wish to consider these materials for various applications by following the path of graphene.

Photonics and optoelectronics of two-dimensional materials beyond graphene

NASA Astrophysics Data System (ADS)

Ponraj, Joice Sophia; Xu, Zai-Quan; Chander Dhanabalan, Sathish; Mu, Haoran; Wang, Yusheng; Yuan, Jian; Li, Pengfei; Thakur, Siddharatha; Ashrafi, Mursal; Mccoubrey, Kenneth; Zhang, Yupeng; Li, Shaojuan; Zhang, Han; Bao, Qiaoliang

2016-11-01

Apart from conventional materials, the study of two-dimensional (2D) materials has emerged as a significant field of study for a variety of applications. Graphene-like 2D materials are important elements of potential optoelectronics applications due to their exceptional electronic and optical properties. The processing of these materials towards the realization of devices has been one of the main motivations for the recent development of photonics and optoelectronics. The recent progress in photonic devices based on graphene-like 2D materials, especially topological insulators (TIs) and transition metal dichalcogenides (TMDs) with the methodology level discussions from the viewpoint of state-of-the-art designs in device geometry and materials are detailed in this review. We have started the article with an overview of the electronic properties and continued by highlighting their linear and nonlinear optical properties. The production of TIs and TMDs by different methods is detailed. The following main applications focused towards device fabrication are elaborated: (1) photodetectors, (2) photovoltaic devices, (3) light-emitting devices, (4) flexible devices and (5) laser applications. The possibility of employing these 2D materials in different fields is also suggested based on their properties in the prospective part. This review will not only greatly complement the detailed knowledge of the device physics of these materials, but also provide contemporary perception for the researchers who wish to consider these materials for various applications by following the path of graphene.

Methods and Devices for Micro-Isolation, Extraction, and/or Analysis of Microscale Components

NASA Technical Reports Server (NTRS)

Wade, Lawrence A. (Inventor); Kartalov, Emil P. (Inventor); Taylor, Clive (Inventor); Shibata, Darryl (Inventor)

2014-01-01

Provided herein are devices and methods for the micro-isolation of biological cellular material. A micro-isolation apparatus described can comprise a photomask that protects regions of interest against DNA-destroying illumination. The micro-isolation apparatus can further comprise photosensitive material defining access wells following illumination and subsequent developing of the photosensitive material. The micro-isolation apparatus can further comprise a chambered microfluidic device comprising channels providing access to wells defined in photosensitive material. The micro-isolation apparatus can comprise a chambered microfluidic device without access wells defined in photosensitive material where valves control the flow of gases or liquids through the channels of the microfluidic device. Also included are methods for selectively isolating cellular material using the apparatuses described herein, as are methods for biochemical analysis of individual regions of interest of cellular material using the devices described herein. Further included are methods of making masking arrays useful for the methods described herein.

Design, fabrication and testing of porous tungsten vaporizers for mercury ion thrusters

NASA Technical Reports Server (NTRS)

Zavesky, R.; Kroeger, E.; Kami, S.

1983-01-01

The dispersions in the characteristics, performance and reliability of vaporizers for early model 30-cm thrusters were investigated. The purpose of the paper is to explore the findings and to discuss the approaches that were taken to reduce the observed dispersion and present the results of a program which validated those approaches. The information that is presented includes porous tungsten materials specifications, a discussion of assembly procedures, and a description of a test program which screens both material and fabrication processes. There are five appendices providing additional detail in the areas of vaporizer contamination, nitrogen flow testing, bubble testing, porosimeter testing, and mercury purity. Four neutralizers, seven cathodes and five main vaporizers were successfully fabricated, tested, and operated on thrusters. Performance data from those devices is presented and indicates extremely repeatable results from using the design and fabrication procedures.

32 CFR 22.105 - Definitions.

Code of Federal Regulations, 2010 CFR

2010-07-01

... applying existing technology to new products and processes in a general way. Advanced research is most... Category 6.3A) programs within Research, Development, Test and Evaluation (RDT&E). Applied research... technology such as new materials, devices, methods and processes. It typically is funded in Applied Research...

Active Member Design, Modeling, and Verification

NASA Technical Reports Server (NTRS)

Umland, Jeffrey W.; Webster, Mark; John, Bruce

1993-01-01

The design and development of active members intended for use in structural control applications is presented. The use of three different solid state actuation materials, namely, piezoelectric, electrostictive, and magnetostrictive, is discussed. Test data is given in order to illustrate the actuator and device characteristics and performance.

Printed Circuit Board Quality Assurance

NASA Technical Reports Server (NTRS)

Sood, Bhanu

2016-01-01

PCB Assurance Summary: PCB assurance actives are informed by risk in context of the Project. Lessons are being applied across Projects for continuous improvements. Newer component technologies, smaller/high pitch devices: tighter and more demanding PCB designs: Identifying new research areas. New materials, designs, structures and test methods.

10 CFR 36.1 - Purpose and scope.

Code of Federal Regulations, 2014 CFR

2014-01-01

... area subject to irradiation are contained within a device and are not accessible by personnel), medical radiology or teletherapy, radiography (the irradiation of materials for nondestructive testing purposes), gauging, or open-field (agricultural) irradiations. [58 FR 7728, Feb. 9, 1993, as amended at 78 FR 17007...

Pressure Effects on the Self-Extinguishment Limits of Aerospace Materials

NASA Technical Reports Server (NTRS)

Hirsch, David B.; Williams, James H.; Haas, Jon P.; Beeson, Harold D.; Ruff, Gary A.; Pedley, Michael D.

2009-01-01

The Orion Crew Exploration Vehicle Module (CM) is being designed to operate in an atmosphere of up to 30% oxygen at a pressure of 10.2 psia for lunar missions. Spacecraft materials selection is based on an upward flammability test conducted in a closed chamber under the worst expected conditions of pressure and oxygen concentration. Material flammability depends on both oxygen concentration and pressure but, since oxygen concentration is the primary driver, all materials are certified in the 30% oxygen, 10.2 psia environment. Extensive data exist from the Shuttle Program at this condition which used relatively the same test methodology as currently used in the Constellation Program. When the CM returns to Earth, a snorkel device will be activated after splashdown to provide outside air to the crew; however, for operational reasons, it is desirable to maximize the time the crew is able to breathe cabin air before the snorkel device is activated. To maximize this time, it has been proposed to raise the partial pressure of oxygen in the CM immediately before reentry while maintaining the total cabin pressure at 14.7 psia. In addition, it has been proposed to leak-test the Orion CM with ambient air at a maximum pressure of 17.3 psia. No data exist to assess how high the cabin oxygen concentration can be at 14.7 psia or 17.3 psia. One is to re-test a large number of materials at these pressures at a significant cost. However, since the maximum oxygen concentration (MOC) at which a material will self-extinguish has been determined for a variety of spacecraft materials as a function of pressure, a second alternative is to use existing data to estimate the MOC at 14.7 psia and 17.3 psia. This data will be examined in this paper and an analysis presented to determine the oxygen concentrations at the increased pressures that will result in self-extinguishment of a material. This analysis showed that the oxygen concentration for the Orion CM at 14.7 psia cannot be set higher than 25.6% without potentially invalidating the materials flammability certification in 30% oxygen at 10.2 psia for some materials. Materials certified under these conditions would still be self-extinguishing in ambient air at 17.3 psia. alternative

14 MeV Neutron Irradiation Effect on Superconducting Magnet Materials for Fusion Device

NASA Astrophysics Data System (ADS)

Nishimura, A.; Hishinuma, Y.; Seo, K.; Tanaka, T.; Muroga, T.; Nishijima, S.; Katagiri, K.; Takeuchi, T.; Shindo, Y.; Ochiai, K.; Nishitani, T.; Okuno, K.

2006-03-01

As a large-scale plasma experimental device is planned and designed, the importance of investigations on irradiation effect of 14 MeV neutron increases and an experimental database is desired to be piled up. Recently, intense streaming of fast neutron from ports are reported and degradation of superconducting magnet performance is anticipated. To investigate the pure neutron effect on superconducting magnet materials, a cryogenic target system was newly developed and installed at Fusion Neutronics Source in Japan Atomic Energy Research Institute. Although production rate of 14 MeV neutron is not large, only 14 MeV neutron can be supplied to irradiation test without gamma ray. Copper wires, superconducting wires, glass fiber reinforced composites are irradiated and the irradiation effects are characterized. At the same time, sensors for measuring temperature and magnetic field are irradiated and their performance was investigated after irradiation. This paper presents outline of the cryogenic target system and some irradiation test results.

49 CFR 571.139 - Standard No. 139; New pneumatic radial tires for light vehicles.

Code of Federal Regulations, 2014 CFR

2014-10-01

... part of the tire that is made of steel wires, wrapped or reinforced by ply cords and that is shaped to... mechanical device made of rubber, chemicals, fabric and steel or other materials, that, when mounted on an....Test sample. For the tests specified in S6, use: (a) One tire for high speed; (b) Another tire for...

49 CFR 571.139 - Standard No. 139; New pneumatic radial tires for light vehicles.

Code of Federal Regulations, 2013 CFR

2013-10-01

... part of the tire that is made of steel wires, wrapped or reinforced by ply cords and that is shaped to... mechanical device made of rubber, chemicals, fabric and steel or other materials, that, when mounted on an....Test sample. For the tests specified in S6, use: (a) One tire for high speed; (b) Another tire for...

49 CFR 571.139 - Standard No. 139; New pneumatic radial tires for light vehicles.

Code of Federal Regulations, 2012 CFR

2012-10-01

... part of the tire that is made of steel wires, wrapped or reinforced by ply cords and that is shaped to... mechanical device made of rubber, chemicals, fabric and steel or other materials, that, when mounted on an....Test sample. For the tests specified in S6, use: (a) One tire for high speed; (b) Another tire for...

Mechanical Properties of Polymers Used for Anatomical Components in the Warrior Injury Assessment Manikin (WIAMan) Technology Demonstrator

DTIC Science & Technology

2016-07-01

14. ABSTRACT The Warrior Injury Assessment Manikin was developed to provide an instrumented anthropomorphic test device (ATD) specifically...underbody blasts . To achieve that goal, the ATD used numerous polymeric materials for component parts that simulate human tissue and enable compliance in...strain rate, underbody blast , mechanical testing, tension, compression 16. SECURITY CLASSIFICATION OF: 17. LIMITATION OF ABSTRACT

Passive and Active Control of Space Structures (PACOSS)

NASA Astrophysics Data System (ADS)

Morosow, G.; Harcrow, H.; Rogers, L.

1985-04-01

Passive and Active Control of Space Structures (PACOSS) is a five-year program designed to investigate highly damped structures in conjunction with active control systems, and in particular to develop technology that integrates passive damping and active control to achieve precise pointing control. Major areas of research include metal matrix composites; viscoelastic materials; damping devices; dynamic test article design, fabrication and testing; and active damping.

Organic electrophosphorescence device having interfacial layers

DOEpatents

Choulis, Stelios A.; Mathai, Mathew; Choong, Vi-En; So, Franky

2010-08-10

Techniques are described for forming an organic light emitting diode device with improved device efficiency. Materials having at least one energy level that is similar to those of a phosphorescent light emitting material in the diode are incorporated into the device to directly inject holes or electrons to the light emitting material.

Laser Processing of Multilayered Thermal Spray Coatings: Optimal Processing Parameters

NASA Astrophysics Data System (ADS)

Tewolde, Mahder; Zhang, Tao; Lee, Hwasoo; Sampath, Sanjay; Hwang, David; Longtin, Jon

2017-12-01

Laser processing offers an innovative approach for the fabrication and transformation of a wide range of materials. As a rapid, non-contact, and precision material removal technology, lasers are natural tools to process thermal spray coatings. Recently, a thermoelectric generator (TEG) was fabricated using thermal spray and laser processing. The TEG device represents a multilayer, multimaterial functional thermal spray structure, with laser processing serving an essential role in its fabrication. Several unique challenges are presented when processing such multilayer coatings, and the focus of this work is on the selection of laser processing parameters for optimal feature quality and device performance. A parametric study is carried out using three short-pulse lasers, where laser power, repetition rate and processing speed are varied to determine the laser parameters that result in high-quality features. The resulting laser patterns are characterized using optical and scanning electron microscopy, energy-dispersive x-ray spectroscopy, and electrical isolation tests between patterned regions. The underlying laser interaction and material removal mechanisms that affect the feature quality are discussed. Feature quality was found to improve both by using a multiscanning approach and an optional assist gas of air or nitrogen. Electrically isolated regions were also patterned in a cylindrical test specimen.

High strength fused silica flexures manufactured by femtosecond laser

NASA Astrophysics Data System (ADS)

Bellouard, Yves; Said, Ali A.; Dugan, Mark; Bado, Philippe

2009-02-01

Flexures are mechanical elements used in micro- and precision-engineering to precisely guide the motion of micro-parts. They consist of slender bodies that deform elastically upon the application of a force. Although counter-intuitive at first, fused silica is an attractive material for flexure. Pending that the machining process does not introduce surface flaws that would lead to catastrophic failure, the material has a theoretically high ultimate tensile strength of several GPa. We report on high-aspect ratio fused silica flexures manufactured by femtosecond laser combined with chemical etching. Notch-hinges with thickness as small as twenty microns and aspect ratios comparable to aspect ratios obtained by Deep- Reactive-Ion-Etching (DRIE) were fabricated and tested under different loading conditions. Multiple fracture tests were performed for various loading conditions and the cracks morphologies were analyzed using Scanning Electron Microscopy. The manufactured elements show outstanding mechanical properties with flexural strengths largely exceeding those obtained with other technologies and materials. Fused silica flexures offer a mean to combine integrated optics with micro-mechanics in a single monolithic substrate. Waveguides and mechanical elements can be combined in a monolithic devices opening new opportunities for integrated opto-mechatronics devices.

Static and dynamic fatigue behavior of topology designed and conventional 3D printed bioresorbable PCL cervical interbody fusion devices.

PubMed

Knutsen, Ashleen R; Borkowski, Sean L; Ebramzadeh, Edward; Flanagan, Colleen L; Hollister, Scott J; Sangiorgio, Sophia N

2015-09-01

Recently, as an alternative to metal spinal fusion cages, 3D printed bioresorbable materials have been explored; however, the static and fatigue properties of these novel cages are not well known. Unfortunately, current ASTM testing standards used to determine these properties were designed prior to the advent of bioresorbable materials for cages. Therefore, the applicability of these standards for bioresorbable materials is unknown. In this study, an image-based topology and a conventional 3D printed bioresorbable poly(ε)-caprolactone (PCL) cervical cage design were tested in compression, compression-shear, and torsion, to establish their static and fatigue properties. Difficulties were in fact identified in establishing failure criteria and in particular determining compressive failure load. Given these limitations, under static loads, both designs withstood loads of over 650 N in compression, 395 N in compression-shear, and 0.25 Nm in torsion, prior to yielding. Under dynamic testing, both designs withstood 5 million (5M) cycles of compression at 125% of their respective yield forces. Geometry significantly affected both the static and fatigue properties of the cages. The measured compressive yield loads fall within the reported physiological ranges; consequently, these PCL bioresorbable cages would likely require supplemental fixation. Most importantly, supplemental testing methods may be necessary beyond the current ASTM standards, to provide more accurate and reliable results, ultimately improving preclinical evaluation of these devices. Copyright © 2015 Elsevier Ltd. All rights reserved.

Forced Ion Migration for Chalcogenide Phase Change Memory Device

NASA Technical Reports Server (NTRS)

Campbell, Kristy A (Inventor)

2013-01-01

Non-volatile memory devices with two stacked layers of chalcogenide materials comprising the active memory device have been investigated for their potential as phase-change memories. The devices tested included GeTe/SnTe, Ge2Se3/SnTe, and Ge2Se3/SnSe stacks. All devices exhibited resistance switching behavior. The polarity of the applied voltage with respect to the SnTe or SnSe layer was critical to the memory switching properties, due to the electric field induced movement of either Sn or Te into the Ge-chalcogenide layer. One embodiment of the invention is a device comprising a stack of chalcogenide-containing layers which exhibit phase-change switching only after a reverse polarity voltage potential is applied across the stack causing ion movement into an adjacent layer and thus "activating" the device to act as a phase-change random access memory device or a reconfigurable electronics device when the applied voltage potential is returned to the normal polarity. Another embodiment of the invention is a device that is capable of exhibiting more than two data states.

Forced ion migration for chalcogenide phase change memory device

NASA Technical Reports Server (NTRS)

Campbell, Kristy A. (Inventor)

2011-01-01

Non-volatile memory devices with two stacked layers of chalcogenide materials comprising the active memory device have been investigated for their potential as phase change memories. The devices tested included GeTe/SnTe, Ge.sub.2Se.sub.3/SnTe, and Ge.sub.2Se.sub.3/SnSe stacks. All devices exhibited resistance switching behavior. The polarity of the applied voltage with respect to the SnTe or SnSe layer was critical to the memory switching properties, due to the electric field induced movement of either Sn or Te into the Ge-chalcogenide layer. One embodiment of the invention is a device comprising a stack of chalcogenide-containing layers which exhibit phase change switching only after a reverse polarity voltage potential is applied across the stack causing ion movement into an adjacent layer and thus "activating" the device to act as a phase change random access memory device or a reconfigurable electronics device when the applied voltage potential is returned to the normal polarity. Another embodiment of the invention is a device that is capable of exhibiting more that two data states.

Forced ion migration for chalcogenide phase change memory device

NASA Technical Reports Server (NTRS)

Campbell, Kristy A. (Inventor)

2012-01-01

Non-volatile memory devices with two stacked layers of chalcogenide materials comprising the active memory device have been investigated for their potential as phase-change memories. The devices tested included GeTe/SnTe, Ge.sub.2Se.sub.3/SnTe, and Ge.sub.2Se.sub.3/SnSe stacks. All devices exhibited resistance switching behavior. The polarity of the applied voltage with respect to the SnTe or SnSe layer was critical to the memory switching properties, due to the electric field induced movement of either Sn or Te into the Ge-chalcogenide layer. One embodiment of the invention is a device comprising a stack of chalcogenide-containing layers which exhibit phase-change switching only after a reverse polarity voltage potential is applied across the stack causing ion movement into an adjacent layer and thus "activating" the device to act as a phase-change random access memory device or a reconfigurable electronics device when the applied voltage potential is returned to the normal polarity. Another embodiment of the invention is a device that is capable of exhibiting more than two data states.

The role of mechanical properties in cavitation erosion resistance. [parameters affecting metal fatigue under cavitation flow conditions

NASA Technical Reports Server (NTRS)

Gould, G. C.

1974-01-01

Methods for determining the correlations of erosion resistance and mechanical properties of materials are discussed. The most common method of testing cavitation erosion resistance of materials is the vibratory cavitation probe. The instrument and its operation are described. The use of the whirling arm device is considered as a second method. Metallographic investigations of the earliest stages of cavitation erosion damage of metallic materials was conducted. The materials show plastic deformation occurring during the incubation period and increasing until cracks form and metal fragments are lost. The parameters of the work done to cause material fractures are identified. The reactions obtained with specific materials are reported.

A tensile machine with a novel optical load cell for soft biological tissues application.

PubMed

Faturechi, Rahim; Hashemi, Ata; Abolfathi, Nabiollah

2014-11-01

The uniaxial tensile testing machine is the most common device used to measure the mechanical properties of industrial and biological materials. The need for a low-cost uniaxial tension testing device for small research centers has always been the subject of research. To address this need, a novel uniaxial tensile testing machine was designed and fabricated to measure the mechanical properties of soft biological tissues. The device is equipped with a new low-cost load cell which works based on the linear displacement/force relationship of beams. The deflection of the beam load cell is measured optically by a digital microscope with an accuracy of 1 µm. The stiffness of the designed load cell was experimentally and theoretically determined at 100 N mm(-1). The stiffness of the load cell can be easily adjusted according to the tissue's strength. The force-time behaviour of soft tissue specimens was obtained by an in-house image processing program. To demonstrate the efficiency of the fabricated device, the mechanical properties of amnion tissue was measured and compared with available data. The obtained results indicate a strong agreement with that of previous studies.

Vape Factor Fast Find-Adult (VF3-A): a prototype survey method for recording brand-specific vaping factors in adult populations.

PubMed

Ross, Craig S; Zhang, Tancy C; DeJong, William; Siegel, Michael

2018-03-23

In population studies, vaping is often treated as a dichotomous exposure (present/absent) without consideration of specific vaping devices and materials being used. A survey instrument is needed to record specific vaping devices and materials. We developed a database of 613 vaping device models and 3196 vaping liquid products, indexed by device brand, device type, liquid brand, liquid name and liquid flavour type. We developed a survey instrument to allow participants to report their vaping device and liquid from the indexed lists. The survey was pilot tested with a convenience sample of 208 adults (≥age 21). We validated the vaping device and liquid responses with a recontact survey. We report the proportion of respondents finding their products, characteristics of people finding their products and survey response times. Devices used most frequently in the past 30 days were electronic cigarettes (33% of respondents), vaping pens (28%) and vaping mods (16%). Fifty-seven per cent used liquids containing nicotine most frequently in the past 30 days, followed by liquids without nicotine (20%) and marijuana or hashish (10%). Most (85%) participants found their vaping device successfully (median 19.7 s) and 74% found their vaping liquid (median 19.8 s). Females and older adults were less likely to find their devices and liquids. Responses were validated for 91% and 76% of devices and e-liquids, respectively. This study demonstrated the feasibility of an internet-based survey instrument to record specific vaping factors for use in studies of vaping and health. © Article author(s) (or their employer(s) unless otherwise stated in the text of the article) 2018. All rights reserved. No commercial use is permitted unless otherwise expressly granted.

Science and Emerging Technology of 2D Atomic Layered Materials and Devices

DTIC Science & Technology

2017-09-09

AFRL-AFOSR-JP-TR-2017-0067 Science & Emerging Technology of 2D Atomic Layered Materials and Devices Angel Rubio UNIVERSIDAD DEL PAIS VASCO - EUSKAL...Emerging Technology of 2D Atomic Layered Materials and Devices 5a.  CONTRACT NUMBER 5b.  GRANT NUMBER FA2386-15-1-0006 5c.  PROGRAM ELEMENT NUMBER...reporting documents for AOARD project 144088, “2D Materials and Devices Beyond Graphene Science & Emerging Technology of 2D Atomic Layered Materials and

Mid-Infrared Optoelectronics: Materials and Devices. MIOMD-XII

DTIC Science & Technology

2014-10-01

current. An enhancement of the QEPAS signal can be achieved when two metallic tubes acting as a micro‐ resonator (mR) are added to the QTF sensor ...spectrophone configuration using a 5.8 mm long micro‐ resonator with an inner diameter of 0.80 mm [3]. In order to test and validate the developed QEPAS sensor ...materials, photodetectors, sensors and applications have been discussed in other sessions. The papers were submitted by researchers representing 107

Organo-metallic elements for associative information processing

NASA Astrophysics Data System (ADS)

Potember, Richard S.; Poehler, Theodore O.

1989-01-01

In the three years of the program we have: (1) built and tested a 4 bit element matrix device for possible use in high density content-addressable memories systems; (2) established a test and evaluation laboratory to examine optical materials for nonlinear effects, saturable absorption, harmonic generation and photochromism; (3) successfully designed, constructed and operated a codeposition processing system that enables organic materials to be deposited on a variety of substrates to produce optical grade coatings and films. This system is also compatible with other traditional microelectronic techniques; (4) used the sol-gel process with colloidal AgTCNQ to fabricate high speed photochromic switches; (5) develop and applied for patent coverage to make VO2 optical switching materials via the sol-gel processing using vanadium (IV) alkoxide compounds.

Functionalization of carbon fiber tows with ZnO nanorods for stress sensor integration in smart composite materials.

PubMed

Calestani, D; Culiolo, M; Villani, M; Delmonte, D; Solzi, M; Kim, Tae-Yun; Kim, Sang-Woo; Marchini, L; Zappettini, A

2018-08-17

The physical and operating principle of a stress sensor, based on two crossing carbon fibers functionalized with ZnO nanorod-shaped nanostructures, was recently demonstrated. The functionalization process has been here extended to tows made of one thousand fibers, like those commonly used in industrial processing, to prove the idea that the same working principle can be exploited in the creation of smart sensing carbon fiber composites. A stress-sensing device made of two functionalized tows, fixed with epoxy resin and crossing like in a typical carbon fiber texture, was successfully tested. Piezoelectric properties of single nanorods, as well as those of the test device, were measured and discussed.

Encapsulation methods and dielectric layers for organic electrical devices

DOEpatents

Blum, Yigal D; Chu, William Siu-Keung; MacQueen, David Brent; Shi, Yijan

2013-07-02

The disclosure provides methods and materials suitable for use as encapsulation barriers and dielectric layers in electronic devices. In one embodiment, for example, there is provided an electroluminescent device or other electronic device with a dielectric layer comprising alternating layers of a silicon-containing bonding material and a ceramic material. The methods provide, for example, electronic devices with increased stability and shelf-life. The invention is useful, for example, in the field of microelectronic devices.

An instrument for spatial conductivity measurements of high Tc superconducting (HTSC) materials

NASA Technical Reports Server (NTRS)

Vansant, T.

1991-01-01

High T(sub c) Superconducting (HTSC) thin films are suggested for use in a number of aerospace applications such as an IR bolometer and as electromagnetic shielding. As part of its flight assurance role, the Materials Branch of the Goddard Space Flight Center has initiated development of an instrument capable of measuring variations in conductivity for flat samples using an eddy current testing device and an X-Y positioning table. This instrument was used to examine bulk HTSC samples. System changes that would enable characterization of thin film materials are discussed.

Methods of producing free-standing semiconductors using sacrificial buffer layers and recyclable substrates

DOEpatents

Ptak, Aaron Joseph; Lin, Yong; Norman, Andrew; Alberi, Kirstin

2015-05-26

A method of producing semiconductor materials and devices that incorporate the semiconductor materials are provided. In particular, a method is provided of producing a semiconductor material, such as a III-V semiconductor, on a spinel substrate using a sacrificial buffer layer, and devices such as photovoltaic cells that incorporate the semiconductor materials. The sacrificial buffer material and semiconductor materials may be deposited using lattice-matching epitaxy or coincident site lattice-matching epitaxy, resulting in a close degree of lattice matching between the substrate material and deposited material for a wide variety of material compositions. The sacrificial buffer layer may be dissolved using an epitaxial liftoff technique in order to separate the semiconductor device from the spinel substrate, and the spinel substrate may be reused in the subsequent fabrication of other semiconductor devices. The low-defect density semiconductor materials produced using this method result in the enhanced performance of the semiconductor devices that incorporate the semiconductor materials.

Use of silicon oxynitride as a sacrificial material for microelectromechanical devices

DOEpatents

Habermehl, Scott D.; Sniegowski, Jeffry J.

2001-01-01

The use of silicon oxynitride (SiO.sub.x N.sub.y) as a sacrificial material for forming a microelectromechanical (MEM) device is disclosed. Whereas conventional sacrificial materials such as silicon dioxide and silicate glasses are compressively strained, the composition of silicon oxynitride can be selected to be either tensile-strained or substantially-stress-free. Thus, silicon oxynitride can be used in combination with conventional sacrificial materials to limit an accumulation of compressive stress in a MEM device; or alternately the MEM device can be formed entirely with silicon oxynitride. Advantages to be gained from the use of silicon oxynitride as a sacrificial material for a MEM device include the formation of polysilicon members that are substantially free from residual stress, thereby improving the reliability of the MEM device; an ability to form the MEM device with a higher degree of complexity and more layers of structural polysilicon than would be possible using conventional compressively-strained sacrificial materials; and improved manufacturability resulting from the elimination of wafer distortion that can arise from an excess of accumulated stress in conventional sacrificial materials. The present invention is useful for forming many different types of MEM devices including accelerometers, sensors, motors, switches, coded locks, and flow-control devices, with or without integrated electronic circuitry.

ORNL Trusted Corridors Project: Watts Bar Dam Inland Waterway Project

DOE Office of Scientific and Technical Information (OSTI.GOV)

Walker, Randy M; Gross, Ian G; Smith, Cyrus M

2011-11-01

Radiation has existed everywhere in the environment since the Earth's formation - in rocks, soil, water, and plants. The mining and processing of naturally occurring radioactive materials for use in medicine, power generation, consumer products, and industry inevitably generate emissions and waste. Radiological measuring devices have been used by industry for years to measure for radiation in undesired locations or simply identify radioactive materials. Since the terrorist attacks on the United States on 9-11-01 these radiation measuring devices have proliferated in many places in our nation's commerce system. DOE, TVA, the Army Corps and ORNL collaborated to test the usefulnessmore » of these devices in our nation's waterway system on this project. The purpose of the Watts Bar Dam ORNL Trusted Corridors project was to investigate the security, safety and enforcement needs of local, state and federal government entities for state-of-the-art sensor monitoring in regards to illegal cargo including utilization of the existing infrastructure. TVA's inland waterways lock system is a recognized and accepted infrastructure by the commercial carrier industry. Safety Monitoring activities included tow boat operators, commercial barges and vessels, recreational watercraft and their cargo, identification of unsafe vessels and carriers, and, monitoring of domestic and foreign commercial vessels and cargo identification. Safety Enforcement activities included cargo safety, tracking, identification of hazardous materials, waterway safety regulations, and hazardous materials regulations. Homeland Security and Law Enforcement Applications included Radiological Dispersive Devices (RDD) identification, identification of unsafe or illicit transport of hazardous materials including chemicals and radiological materials, and screening for shipments of illicit drugs. In the Fall of 2005 the SensorNet funding for the project expired. After several unsuccessful attempts to find a Federal sponsor to continue with the project, the Watts Bar Dam Project was canceled and the Exploranium radiation monitors were removed from the doors of Watts Bar Dam in early 2006. The DHS Domestic Nuclear Detection Office decided to proceed with a Pilot building on the ORNL work performed at the TN and SC weigh stations in the highway sector of the Trusted Corridors project and eventually expanded it to other southern states under the name of Southeastern Corridor Pilot Project (SETCP). Many of the Phase I goals were achieved however real-world test data of private watercraft and barges was never obtained.« less

Mass Transport of Condensed Species in Aerodynamic Fallout Glass from a Near-Surface Nuclear Test

NASA Astrophysics Data System (ADS)

Weisz, David Gabriel

In a near-surface nuclear explosion, vaporized device materials are incorporated into molten soil and other carrier materials, forming glassy fallout upon quenching. Mechanisms by which device materials mix with carrier materials have been proposed, however, the specific mechanisms and physical conditions by which soil and other carrier materials interact in the fireball, as well as the subsequent incorporation of device materials with carrier materials, are not well constrained. A surface deposition layer was observed preserved at interfaces where two aerodynamic fallout glasses agglomerated and fused. Eleven such boundaries were studied using spatially resolved analyses to better understand the vaporization and condensation behavior of species in the fireball. Using nano-scale secondary ion mass spectrometry (NanoSIMS), we identified higher concentrations of uranium from the device in 7 of the interface layers, as well as isotopic enrichment (>75% 235U) in 9 of the interface layers. Major element analysis of the interfaces revealed the deposition layer to be chemically enriched in Fe-, Ca- and Na-bearing species and depleted in Ti- and Al-bearing species. The concentration profiles of the enriched species at the interface are characteristic of diffusion. Three of the uranium concentration profiles were fit with a modified Gaussian function, representative of 1-D diffusion from a planar source, to determine time and temperature parameters of mass transport. By using a historical model of fireball temperature to simulate the cooling rate at the interface, the temperature of deposition was estimated to be 2200 K, with 1? uncertainties in excess of 140 K. The presence of Na-species in the layers at this estimated temperature of deposition is indicative of an oxygen rich fireball. The notable depletion of Al-species, a refractory oxide that is highly abundant in the soil, together with the enrichment of Ca-, Fe-, and 235U-species, suggests an anthropogenic source of the enriched species, together with a continuous chemical fractionation process as these species condensed.

21 CFR 870.3710 - Pacemaker repair or replacement material.

Code of Federal Regulations, 2012 CFR

2012-04-01

... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Pacemaker repair or replacement material. 870.3710... (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices § 870.3710 Pacemaker repair or replacement material. (a) Identification. A pacemaker repair or replacement material is an...

21 CFR 870.3710 - Pacemaker repair or replacement material.

Code of Federal Regulations, 2011 CFR

2011-04-01

... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Pacemaker repair or replacement material. 870.3710... (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices § 870.3710 Pacemaker repair or replacement material. (a) Identification. A pacemaker repair or replacement material is an...

21 CFR 870.3710 - Pacemaker repair or replacement material.

Code of Federal Regulations, 2014 CFR

2014-04-01

... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Pacemaker repair or replacement material. 870.3710... (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices § 870.3710 Pacemaker repair or replacement material. (a) Identification. A pacemaker repair or replacement material is an...

21 CFR 870.3710 - Pacemaker repair or replacement material.

Code of Federal Regulations, 2013 CFR

2013-04-01

... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Pacemaker repair or replacement material. 870.3710... (CONTINUED) MEDICAL DEVICES CARDIOVASCULAR DEVICES Cardiovascular Prosthetic Devices § 870.3710 Pacemaker repair or replacement material. (a) Identification. A pacemaker repair or replacement material is an...

An in vitro analysis of a carotid artery stent with a protective porous membrane.

PubMed

Müller-Hülsbeck, Stefan; Hüsler, Erhard J; Schaffner, Silvio R; Jahnke, Thomas; Glass, Christoph; Wenke, Rüdiger; Heller, Martin

2004-11-01

To prove the effectiveness of a new stent concept with integrated protection (MembraX [MX]) by comparing it with five cerebral protection devices designed for carotid angioplasty in an in vitro model. Two simulation series of embolization from carotid angioplasty have been performed. In the first series, polyvinyl-alcohol particles (150-250 microm [small], 355-500 microm [medium], 710-1000 microm [large]; 5 mg each) were injected into a silicone flow model simulating the aortic arch with a carotid bifurcation. The particles were injected proximally to the partially deployed MX stent or one of the following protection devices: Angioguard (AG), FilterWire EX (EX), Trap, Neuroshield (NS), or GuardWire Plus (GW). Particles evading the protection device were caught in a filter at the end of the flow model and weighed. In the second series, human plaque material (8-12 particles; total weight 6.09 +/- 0.01 mg; 500-1500 microm) was injected into the model with the respective devices. MX was compared with the AG, EX, Trap, and NS devices. MX had the most effective overall filtration performance for polyvinyl alcohol particles in the effluent of the internal carotid artery (ICA; 0.43 mg, 2.9%), compared with NS (0.53 mg, 3.5%), GW (1.10 mg, 7.0%), EX and AG (1.18 and 1.21 mg, respectively; 7.8% and 8.0%), and Trap (1.24 mg, 8.2%). MX performed best for the small particles (2.0% passed particles into ICA; P < .05 compared with all). Human plaque material was retained best in the in vitro model by MX (0.0%), followed by NS (0.8%), EX (1.3%), Trap (2.6%), and AG (4.4%). In vitro, none of the tested devices had the ability to prevent embolization completely. Comparing current designs, the MX device captured the highest percentage of the three different particle groups. Tested with human plaque emboli, MX performed effectively in filtering the particles in the ICA.

Examination of a size-change test for photovoltaic encapsulation materials

NASA Astrophysics Data System (ADS)

Miller, David C.; Gu, Xiaohong; Ji, Liang; Kelly, George; Nickel, Nichole; Norum, Paul; Shioda, Tsuyoshi; Tamizhmani, Govindasamy; Wohlgemuth, John H.

2012-10-01

We examine a proposed test standard that can be used to evaluate the maximum representative change in linear dimensions of sheet encapsulation products for photovoltaic modules (resulting from their thermal processing). The proposed protocol is part of a series of material-level tests being developed within Working Group 2 of the Technical Committee 82 of the International Electrotechnical Commission. The characterization tests are being developed to aid module design (by identifying the essential characteristics that should be communicated on a datasheet), quality control (via internal material acceptance and process control), and failure analysis. Discovery and interlaboratory experiments were used to select particular parameters for the size-change test. The choice of a sand substrate and aluminum carrier is explored relative to other options. The temperature uniformity of +/-5°C for the substrate was confirmed using thermography. Considerations related to the heating device (hot-plate or oven) are explored. The time duration of 5 minutes was identified from the time-series photographic characterization of material specimens (EVA, ionomer, PVB, TPO, and TPU). The test procedure was revised to account for observed effects of size and edges. The interlaboratory study identified typical size-change characteristics, and also verified the absolute reproducibility of +/-5% between laboratories.

Micro-channel-based high specific power lithium target

NASA Astrophysics Data System (ADS)

Mastinu, P.; Martın-Hernández, G.; Praena, J.; Gramegna, F.; Prete, G.; Agostini, P.; Aiello, A.; Phoenix, B.

2016-11-01

A micro-channel-based heat sink has been produced and tested. The device has been developed to be used as a Lithium target for the LENOS (Legnaro Neutron Source) facility and for the production of radioisotope. Nevertheless, applications of such device can span on many areas: cooling of electronic devices, diode laser array, automotive applications etc. The target has been tested using a proton beam of 2.8MeV energy and delivering total power shots from 100W to 1500W with beam spots varying from 5mm2 to 19mm2. Since the target has been designed to be used with a thin deposit of lithium and since lithium is a low-melting-point material, we have measured that, for such application, a specific power of about 3kW/cm2 can be delivered to the target, keeping the maximum surface temperature not exceeding 150° C.

Energy Dissipating Devices in Falling Rock Protection Barriers

NASA Astrophysics Data System (ADS)

Castanon-Jano, L.; Blanco-Fernandez, E.; Castro-Fresno, D.; Ballester-Muñoz, F.

2017-03-01

Rockfall is a phenomenon which, when uncontrolled, may cause extensive material damage and personal injury. One of the structures used to avoid accidents caused by debris flows or rockfalls is flexible barriers. The energy dissipating devices which absorb the energy generated by rock impact and reduce the mechanical stresses in the rest of the elements of the structure are an essential part of these kinds of structures. This document proposes an overview of the performance of energy dissipating devices, as well as of the role that they fulfil in the barrier. Furthermore, a compilation and a description of the dissipating elements found in the literature are proposed. Additionally, an analysis has been performed of the aspects taken into account in the design, such as experimental (quasi-static and dynamic) tests observing the variation of the behaviour curve depending on the test speed and numerical simulations by means of several finite element software packages.

Sterilization validation for medical compresses at IRASM multipurpose irradiation facility

NASA Astrophysics Data System (ADS)

Alexandru, Mioara; Ene, Mihaela

2007-08-01

In Romania, IRASM Radiation Processing Center is the unique supplier of radiation sterilization services—industrial scale (ISO 9001:2000 and ISO 13485:2003 certified). Its Laboratory of Microbiological Testing is the sole third party competent laboratory (GLPractice License, ISO 17025 certification in progress) for pharmaceutics and medical devices as well. We here refer to medical compresses as a distinct category of sterile products, made from different kind of hydrophilic materials (cotton, non-woven, polyurethane foam) with or without an impregnated ointment base (paraffin, plant extracts). These products are included in the class of medical devices, but for the sterilization validation, from microbiological point of view, there are important differences in testing method compared to the common medical devices (syringes, catheters, etc). In this paper, we present some results and practical solutions chosen to perform a sterilization validation, compliant with ISO 11137: 2006.

Thermal modeling of phase change solidification in thermal control devices including natural convection effects

NASA Technical Reports Server (NTRS)

Ukanwa, A. O.; Stermole, F. J.; Golden, J. O.

1972-01-01

Natural convection effects in phase change thermal control devices were studied. A mathematical model was developed to evaluate natural convection effects in a phase change test cell undergoing solidification. Although natural convection effects are minimized in flight spacecraft, all phase change devices are ground tested. The mathematical approach to the problem was to first develop a transient two-dimensional conduction heat transfer model for the solidification of a normal paraffin of finite geometry. Next, a transient two-dimensional model was developed for the solidification of the same paraffin by a combined conduction-natural-convection heat transfer model. Throughout the study, n-hexadecane (n-C16H34) was used as the phase-change material in both the theoretical and the experimental work. The models were based on the transient two-dimensional finite difference solutions of the energy, continuity, and momentum equations.

Addition of tracers into the polypropylene in view of automatic sorting of plastic wastes using X-ray fluorescence spectrometry.

PubMed

Bezati, F; Froelich, D; Massardier, V; Maris, E

2010-04-01

This study focused on the detection of rare earth oxides, used as tracers for the identification of polymer materials, using XRF (X-ray fluorescence) spectrometry. The tests were carried out in a test system device which allows the collection of static measurements of the samples' spectrum through the use of energy dispersive X-ray fluorescence technology. A sorting process based on tracers added into the polymer matrix is proposed in order to increase sorting selectivity of polypropylene during end-of-life recycling. Tracers consist of systems formed by one or by several substances dispersed into a material, to add a selective property to it, with the aim of improving the efficiency of sorting and high speed identification. Several samples containing rare earth oxides (Y(2)O(3), CeO(2), Nd(2)O(3), Gd(2)O(3), Dy(2)O(3), Er(2)O(3) and Yb(2)O(3)) in different concentrations were prepared in order to analyse some of the parameters which can influence the detection, such as the concentration of tracers, the acquisition time and the possible overlapping among the tracers. This work shows that by using the XRF test system device, it was possible to detect 5 of the 7 tracers tested for 1min exposure time and at a concentration level of 1000ppm. These two parameters will play an important role in the development of an industrial device, which indicates the necessity of further works that needs to be conducted in order to reduce them. Copyright 2009 Elsevier Ltd. All rights reserved.

Concentrated Solar Thermoelectric Power

DOE Office of Scientific and Technical Information (OSTI.GOV)

Chen, Gang; Ren, Zhifeng

2015-07-09

The goal of this project is to demonstrate in the lab that solar thermoelectric generators (STEGs) can exceed 10% solar-to-electricity efficiency, and STEGs can be integrated with phase-change materials (PCM) for thermal storage, providing operation beyond daylight hours. This project achieved significant progress in many tasks necessary to achieving the overall project goals. An accurate Themoelectric Generator (TEG) model was developed, which included realistic treatment of contact materials, contact resistances and radiative losses. In terms of fabricating physical TEGs, high performance contact materials for skutterudite TE segments were developed, along with brazing and soldering methods to assemble segmented TEGs. Accuratemore » measurement systems for determining device performance (in addition to just TE material performance) were built for this project and used to characterize our TEGs. From the optical components’ side, a spectrally selective cermet surface was developed with high solar absorptance and low thermal emittance, with thermal stability at high temperature. A measurement technique was also developed to determine absorptance and total hemispherical emittance at high temperature, and was used to characterize the fabricated spectrally selective surfaces. In addition, a novel reflective cavity was designed to reduce radiative absorber losses and achieve high receiver efficiency at low concentration ratios. A prototype cavity demonstrated that large reductions in radiative losses were possible through this technique. For the overall concentrating STEG system, a number of devices were fabricated and tested in a custom built test platform to characterize their efficiency performance. Additionally, testing was performed with integration of PCM thermal storage, and the storage time of the lab scale system was evaluated. Our latest testing results showed a STEG efficiency of 9.6%, indicating promising potential for high performance concentrated STEGs.« less

Tunable Dielectric Materials and Devices for Broadband Wireless Communications

NASA Technical Reports Server (NTRS)

Mueller, Carl H.; Miranda, Felix A.; Dayton, James A. (Technical Monitor)

1998-01-01

Wireless and satellite communications are a rapidly growing industries which are slated for explosive growth into emerging countries as well as countries with advanced economies. The dominant trend in wireless communication systems is towards broadband applications such as multimedia file transfer, video transmission and Internet access. These applications require much higher data transmission rates than those currently used for voice transmission applications. To achieve these higher data rates, substantially larger bandwidths and higher carrier frequencies are required. A key roadblock to implementing these systems at K-band (18-26.5 GHz) and Ka-band (26.5-40 GHz) is the need to develop hardware which meets the requirements for high data rate transmission in a cost effective manner. In this chapter, we report on the status of tunable dielectric thin films for devices, such as resonators, filters, phased array antennas, and tunable oscillators, which utilize nonlinear tuning in the control elements. Paraelectric materials such as Barium Strontium Titanate ((Ba, Sr)TiO3) have dielectric constants which can be tuned by varying the magnitude of the electric field across the material. Therefore, these materials can be used to control the frequency and/or phase response of various devices such as electronically steerable phased array antennas, oscillators, and filters. Currently, tunable dielectric devices are being developed for applications which require high tunability, low loss, and good RF power-handling capabilities at microwave and millimeter-wave frequencies. These properties are strongly impacted by film microstructure and device design, and considerable developmental work is still required. However, in the last several years enormous progress has occurred in this field, validating the potential of tunable dielectric technology for broadband wireless communication applications. In this chapter we summarize how film processing techniques, microwave test configurations, and prototype devices have combined to drive the field to its current stage of development.

Accumulation of organic compounds leached from plastic materials used in biopharmaceutical process containers.

PubMed

Jenke, Dennis R; Zietlow, David; Garber, Mary Jo; Sadain, Salma; Reiber, Duane; Terbush, William

2007-01-01

Plastic materials are widely used in medical items, such as solution containers, transfusion sets, transfer tubing, and devices. An emerging trend in the biotechnology industry is the utilization of plastic containers to prepare, transport, and store an assortment of solutions including buffers, media, and in-process and finished product. The direct contact of such containers with the product at one or more points in its lifetime raises the possibility that container leachables may accumulate in the finished product. The interaction between several commercially available container materials and numerous model test solutions (representative of buffers and media used in biopharmaceutical applications) was investigated. This paper summarizes the identification of leachables associated with the container materials and documents the levels to which targeted leachables accumulate in the test solutions under defined storage conditions.

Device for detection and identification of carbon- and nitrogen-containing materials

DOEpatents

Karev, Alexander Ivanovich; Raevsky, Valery Georgievich; Dzhilavyan, Leonid Zavenovich; Laptev, Valery Dmitrievich; Pakhomov, Nikolay Ivanovich; Shvedunov, Vasily Ivanovich; Rykalin, Vladimir Ivanovich; Brothers, Louis Joseph; Wilhide, Larry K

2014-03-25

A device for detection and identification of carbon- and nitrogen-containing materials is described. In particular, the device performs the detection and identification of carbon- and nitrogen-containing materials by photo-nuclear detection. The device may comprise a race-track microtron, a breaking target, and a water-filled Cherenkov radiation counter.

Bio-inspired Design Approached Antifouling Strategies

NASA Astrophysics Data System (ADS)

Fitzsimons, L.; Chapman, J.; Lawlor, A.; Regan, F.

2012-04-01

Biofouling exists as the undesirable accumulation of flora and fauna on a given substrate when immersed into an aquatic media. Its presence causes a range of deleterious effects for anyone faced in tackling the problem, which is more than often financially testing. Generally, the initial biofouling stage is stochastic and the attachment of microorganisms held fast in biofilm matrices is irreversible. Stability of the biofilm occurs when exopolymeric substances (EPS) are produced forming a protective surrounding, allowing the cohered microorganisms to colonise and thrive upon the surface. Therefore, if this initial stage of biofilm development can be prevented then it could be possible to prevent subsequent macro events that ensue. Environmental monitoring is one area that faces this challenge and forms the impetus of the work presented herein. In order to improve a monitoring device's lifetime, surface coatings with biocidal agents are applied to counteract these steps. This work shows the development of a range of novel materials, which demonstrate the ability to counteract and inhibit the initial stages of biofouling for monitoring devices. Natural bio-inspired surfaces have been developed using nano-functionalised coatings. All materials are tested in the field and positive results in reducing the biofouling challenge are demonstrated. The results from the deployment of antifouling materials, together with real-time, long-term water quality data from the test site are also shown.

Thick SS316 materials TIG welding development activities towards advanced fusion reactor vacuum vessel applications

NASA Astrophysics Data System (ADS)

Kumar, B. Ramesh; Gangradey, R.

2012-11-01

Advanced fusion reactors like ITER and up coming Indian DEMO devices are having challenges in terms of their materials design and fabrication procedures. The operation of these devices is having various loads like structural, thermo-mechanical and neutron irradiation effects on major systems like vacuum vessel, divertor, magnets and blanket modules. The concept of double wall vacuum vessel (VV) is proposed in view of protecting of major reactor subsystems like super conducting magnets, diagnostic systems and other critical components from high energy 14 MeV neutrons generated from fusion plasma produced by D-T reactions. The double walled vacuum vessel is used in combination with pressurized water circulation and some special grade borated steel blocks to shield these high energy neutrons effectively. The fabrication of sub components in VV are mainly used with high thickness SS materials in range of 20 mm- 60 mm of various grades based on the required protocols. The structural components of double wall vacuum vessel uses various parts like shields, ribs, shells and diagnostic vacuum ports. These components are to be developed with various welding techniques like TIG welding, Narrow gap TIG welding, Laser welding, Hybrid TIG laser welding, Electron beam welding based on requirement. In the present paper the samples of 20 mm and 40 mm thick SS 316 materials are developed with TIG welding process and their mechanical properties characterization with Tensile, Bend tests and Impact tests are carried out. In addition Vickers hardness tests and microstructural properties of Base metal, Heat Affected Zone (HAZ) and Weld Zone are done. TIG welding application with high thick SS materials in connection with vacuum vessel requirements and involved criticalities towards welding process are highlighted.

Processes for multi-layer devices utilizing layer transfer

DOEpatents

Nielson, Gregory N; Sanchez, Carlos Anthony; Tauke-Pedretti, Anna; Kim, Bongsang; Cederberg, Jeffrey; Okandan, Murat; Cruz-Campa, Jose Luis; Resnick, Paul J

2015-02-03

A method includes forming a release layer over a donor substrate. A plurality of devices made of a first semiconductor material are formed over the release layer. A first dielectric layer is formed over the plurality of devices such that all exposed surfaces of the plurality of devices are covered by the first dielectric layer. The plurality of devices are chemically attached to a receiving device made of a second semiconductor material different than the first semiconductor material, the receiving device having a receiving substrate attached to a surface of the receiving device opposite the plurality of devices. The release layer is etched to release the donor substrate from the plurality of devices. A second dielectric layer is applied over the plurality of devices and the receiving device to mechanically attach the plurality of devices to the receiving device.

Design of affordable and ruggedized biomedical devices using virtual instrumentation.

PubMed

Mathern, Ryan Michael; Schopman, Sarah; Kalchthaler, Kyle; Mehta, Khanjan; Butler, Peter

2013-05-01

Abstract This paper presents the designs of four low-cost and ruggedized biomedical devices, including a blood pressure monitor, thermometer, weighing scale and spirometer, designed for the East African context. The design constraints included a mass-production price point of $10, accuracy and precision comparable to commercial devices and ruggedness to function effectively in the harsh environment of East Africa. The blood pressure device, thermometer and weighing scale were field-tested in Kenya and each recorded data within 6% error of the measurements from commercial devices and withstood the adverse climate and rough handling. The spirometer functioned according to specifications, but a re-design is needed to improve operability and usability by patients. This article demonstrates the feasibility of designing and commercializing virtual instrumentation-based biomedical devices in resource-constrained environments through context-driven design. The next steps for the devices include designing them such that they can be more easily manufactured, use standardized materials, are easily calibrated in the field and have more user-friendly software programs that can be updated remotely.

Hybrid Integrated Silicon Microfluidic Platform for Fluorescence Based Biodetection.

PubMed

Chandrasekaran, Arvind; Acharya, Ashwin; You, Jian Liang; Soo, Kim Young; Packirisamy, Muthukumaran; Stiharu, Ion; Darveau, André

2007-09-11

The desideratum to develop a fully integrated Lab-on-a-chip device capable ofrapid specimen detection for high throughput in-situ biomedical diagnoses and Point-of-Care testing applications has called for the integration of some of the novel technologiessuch as the microfluidics, microphotonics, immunoproteomics and Micro ElectroMechanical Systems (MEMS). In the present work, a silicon based microfluidic device hasbeen developed for carrying out fluorescence based immunoassay. By hybrid attachment ofthe microfluidic device with a Spectrometer-on-chip, the feasibility of synthesizing anintegrated Lab-on-a-chip type device for fluorescence based biosensing has beendemonstrated. Biodetection using the microfluidic device has been carried out usingantigen sheep IgG and Alexafluor-647 tagged antibody particles and the experimentalresults prove that silicon is a compatible material for the present application given thevarious advantages it offers such as cost-effectiveness, ease of bulk microfabrication,superior surface affinity to biomolecules, ease of disposability of the device etc., and is thussuitable for fabricating Lab-on-a-chip type devices.

A modified split Hopkinson pressure bar for toughness tests

NASA Astrophysics Data System (ADS)

Granier, N.; Grunenwald, T.

2006-08-01

In order to characterize material toughness or to study crack arrest under dynamic loading conditions, a new testing device has been developed at CEA/Valduc. A new Split Hopkinson Pressure Bar (SHPB) has been modified: it is now composed of a single incident bar and a double transmitter bar. With this facility, a notched specimen can be loaded under three points bending conditions. Qualification tests with titanium and steel notched samples are presented. Data treatment software has been adapted to estimate the sample deflection as a function of time and treat the energy balance. These results are compared with classical Charpy experiments. Effect of various contact areas between specimen and bars are studied to point out their influence on obtained measurements. The advantage of a “knife” contact compared to a plane one is then clearly demonstrated. All results obtained with this new testing device are in good agreement and show a reduced scattering.

Mass production compatible fabrication techniques of single-crystalline silver metamaterials and plasmonics devices

NASA Astrophysics Data System (ADS)

Rodionov, Ilya A.; Baburin, Alexander S.; Zverev, Alexander V.; Philippov, Ivan A.; Gabidulin, Aidar R.; Dobronosova, Alina A.; Ryzhova, Elena V.; Vinogradov, Alexey P.; Ivanov, Anton I.; Maklakov, Sergey S.; Baryshev, Alexander V.; Trofimov, Igor V.; Merzlikin, Alexander M.; Orlikovsky, Nikolay A.; Rizhikov, Ilya A.

2017-08-01

During last 20 years, great results in metamaterials and plasmonic nanostructures fabrication were obtained. However, large ohmic losses in metals and mass production compatibility still represent the most serious challenge that obstruct progress in the fields of metamaterials and plasmonics. Many recent research are primarily focused on developing low-loss alternative materials, such as nitrides, II-VI semiconductor oxides, high-doped semiconductors, or two-dimensional materials. In this work, we demonstrate that our perfectly fabricated silver films can be an effective low-loss material system, as theoretically well-known. We present a fabrication technology of plasmonic and metamaterial nanodevices on transparent (quartz, mica) and non-transparent (silicon) substrates by means of e-beam lithography and ICP dry etch instead of a commonly-used focused ion beam (FIB) technology. We eliminate negative influence of litho-etch steps on silver films quality and fabricate square millimeter area devices with different topologies and perfect sub-100 nm dimensions reproducibility. Our silver non-damage fabrication scheme is tested on trial manufacture of spasers, plasmonic sensors and waveguides, metasurfaces, etc. These results can be used as a flexible device manufacture platform for a broad range of practical applications in optoelectronics, communications, photovoltaics and biotechnology.