Hierarchically nanostructured materials for sustainable environmental applications
Ren, Zheng; Guo, Yanbing; Liu, Cai-Hong; Gao, Pu-Xian
2013-01-01
This review presents a comprehensive overview of the hierarchical nanostructured materials with either geometry or composition complexity in environmental applications. The hierarchical nanostructures offer advantages of high surface area, synergistic interactions, and multiple functionalities toward water remediation, biosensing, environmental gas sensing and monitoring as well as catalytic gas treatment. Recent advances in synthetic strategies for various hierarchical morphologies such as hollow spheres and urchin-shaped architectures have been reviewed. In addition to the chemical synthesis, the physical mechanisms associated with the materials design and device fabrication have been discussed for each specific application. The development and application of hierarchical complex perovskite oxide nanostructures have also been introduced in photocatalytic water remediation, gas sensing, and catalytic converter. Hierarchical nanostructures will open up many possibilities for materials design and device fabrication in environmental chemistry and technology. PMID:24790946
Hierarchically Nanostructured Materials for Sustainable Environmental Applications
NASA Astrophysics Data System (ADS)
Ren, Zheng; Guo, Yanbing; Liu, Cai-Hong; Gao, Pu-Xian
2013-11-01
This article presents a comprehensive overview of the hierarchical nanostructured materials with either geometry or composition complexity in environmental applications. The hierarchical nanostructures offer advantages of high surface area, synergistic interactions and multiple functionalities towards water remediation, environmental gas sensing and monitoring as well as catalytic gas treatment. Recent advances in synthetic strategies for various hierarchical morphologies such as hollow spheres and urchin-shaped architectures have been reviewed. In addition to the chemical synthesis, the physical mechanisms associated with the materials design and device fabrication have been discussed for each specific application. The development and application of hierarchical complex perovskite oxide nanostructures have also been introduced in photocatalytic water remediation, gas sensing and catalytic converter. Hierarchical nanostructures will open up many possibilities for materials design and device fabrication in environmental chemistry and technology.
"Green" electronics: biodegradable and biocompatible materials and devices for sustainable future.
Irimia-Vladu, Mihai
2014-01-21
"Green" electronics represents not only a novel scientific term but also an emerging area of research aimed at identifying compounds of natural origin and establishing economically efficient routes for the production of synthetic materials that have applicability in environmentally safe (biodegradable) and/or biocompatible devices. The ultimate goal of this research is to create paths for the production of human- and environmentally friendly electronics in general and the integration of such electronic circuits with living tissue in particular. Researching into the emerging class of "green" electronics may help fulfill not only the original promise of organic electronics that is to deliver low-cost and energy efficient materials and devices but also achieve unimaginable functionalities for electronics, for example benign integration into life and environment. This Review will highlight recent research advancements in this emerging group of materials and their integration in unconventional organic electronic devices.
Environmental Impacts from Photovoltaic Solar Cells Made with Single Walled Carbon Nanotubes.
Celik, Ilke; Mason, Brooke E; Phillips, Adam B; Heben, Michael J; Apul, Defne
2017-04-18
An ex-ante life cycle inventory was developed for single walled carbon nanotube (SWCNT) PV cells, including a laboratory-made 1% efficient device and an aspirational 28% efficient four-cell tandem device. The environmental impact of unit energy generation from the mono-Si PV technology was used as a reference point. Compared to monocrystalline Si (mono-Si), the environmental impacts from 1% SWCNT was ∼18 times higher due mainly to the short lifetime of three years. However, even with the same short lifetime, the 28% cell had lower environmental impacts than mono-Si. The effects of lifetime and efficiency on the environmental impacts were further examined. This analysis showed that if the SWCNT device efficiency had the same value as the best efficiency of the material under comparison, to match the total normalized impacts of the mono- and poly-Si, CIGS, CdTe, and a-Si devices, the SWCNT devices would need a lifetime of 2.8, 3.5, 5.3, 5.1, and 10.8 years, respectively. It was also found that if the SWCNT PV has an efficiency of 4.5% or higher, its energy payback time would be lower than other existing and emerging PV technologies. The major impacts of SWCNT PV came from the cell's materials synthesis.
29 CFR 1960.26 - Conduct of inspections.
Code of Federal Regulations, 2013 CFR
2013-07-01
... pertinent conditions, structures, machines, apparatus, devices, equipment, and materials therein, and to... environments, the inspector may request employees to wear reasonable and necessary personal monitoring devices... employer shall encourage employees to wear the personal environmental monitoring devices during an...
29 CFR 1960.26 - Conduct of inspections.
Code of Federal Regulations, 2014 CFR
2014-07-01
... pertinent conditions, structures, machines, apparatus, devices, equipment, and materials therein, and to... environments, the inspector may request employees to wear reasonable and necessary personal monitoring devices... employer shall encourage employees to wear the personal environmental monitoring devices during an...
29 CFR 1960.26 - Conduct of inspections.
Code of Federal Regulations, 2012 CFR
2012-07-01
... pertinent conditions, structures, machines, apparatus, devices, equipment, and materials therein, and to... environments, the inspector may request employees to wear reasonable and necessary personal monitoring devices... employer shall encourage employees to wear the personal environmental monitoring devices during an...
29 CFR 1960.26 - Conduct of inspections.
Code of Federal Regulations, 2011 CFR
2011-07-01
... pertinent conditions, structures, machines, apparatus, devices, equipment, and materials therein, and to... environments, the inspector may request employees to wear reasonable and necessary personal monitoring devices... employer shall encourage employees to wear the personal environmental monitoring devices during an...
Energy harvesting: an integrated view of materials, devices and applications.
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.
Environmentally benign semiconductor processing for dielectric etch
NASA Astrophysics Data System (ADS)
Liao, Marci Yi-Ting
Semiconductor processing requires intensive usage of chemicals, electricity, and water. Such intensive resource usage leaves a large impact on the environment. For instance, in Silicon Valley, the semiconductor industry is responsible for 80% of the hazardous waste sites contaminated enough to require government assistance. Research on environmentally benign semiconductor processing is needed to reduce the environmental impact of the semiconductor industry. The focus of this dissertation is on the environmental impact of one aspect of semiconductor processing: patterning of dielectric materials. Plasma etching of silicon dioxide emits perfluorocarbons (PFCs) gases, like C2F6 and CF4, into the atmosphere. These gases are super global warming/greenhouse gases because of their extremely long atmospheric lifetimes and excellent infrared absorption properties. We developed the first inductively coupled plasma (ICP) abatement device for destroying PFCs downstream of a plasma etcher. Destruction efficiencies of 99% and 94% can be obtained for the above mentioned PFCs, by using O 2 as an additive gas. Our results have lead to extensive modeling in academia as well as commercialization of the ICP abatement system. Dielectric patterning of hi-k materials for future device technology brings different environment challenges. The uncertainty of the hi-k material selection and the patterning method need to be addressed. We have evaluated the environmental impact of three different dielectric patterning methods (plasma etch, wet etch and chemical-mechanical polishing), as well as, the transistor device performances associated with the patterning methods. Plasma etching was found to be the most environmentally benign patterning method, which also gives the best device performance. However, the environmental concern for plasma etching is the possibility of cross-contamination from low volatility etch by-products. Therefore, mass transfer in a plasma etcher for a promising hi-k dielectric material, ZrO2, was studied. A novel cross-contamination sampling technique was developed, along with a mass transfer model.
ERIC Educational Resources Information Center
Consumer Dynamics Inc., Rockville, MD.
This module, one of 25 on vocational education training for careers in environmental health occupations, contains self-instructional materials on calibrating a respirable dust sampling device. Following guidelines for students and instructors and an introduction that explains what the student will learn, are three lessons: (1) naming each part of…
2007-06-13
MTOP APS LOS-KE TBX Ceramic Barrel Novel Energetic Materials for the Future Force Multimode HPM and Laser Induced Plasma Channel Technology T Force...in one item • Enhanced incendiary device • Replacement of environmentally unfriendly materials • Insensitive munitions compliance 12 Pyrotechnics...simulators • Pocket sized hand held signals • Replacement of environmentally unfriendly materials • Improve pyrotechnic characteristics with nanotechnologies
NASA Astrophysics Data System (ADS)
Uke, Santosh J.; Akhare, Vijay P.; Bambole, Devidas R.; Bodade, Anjali B.; Chaudhari, Gajanan N.
2017-08-01
In this smart edge, there is an intense demand of portable electronic devices such as mobile phones, laptops, smart watches etc. That demands the use of such components which has light weight, flexible, cheap and environmental friendly. So that needs an evolution in technology. Supercapacitors are energy storage devices emerging as one of the promising energy storage devices in the future energy technology. Electrode material is the important part of supercapacitor. There is much new advancement in types of electrode materials as for supercapacitor. In this review, we focused on the recent advancements in the cobalt oxides, manganese oxides and their composites as an electrodes material for supercapacitor.
Mechanically flexible organic electroluminescent device with directional light emission
Duggal, Anil Raj; Shiang, Joseph John; Schaepkens, Marc
2005-05-10
A mechanically flexible and environmentally stable organic electroluminescent ("EL") device with directional light emission comprises an organic EL member disposed on a flexible substrate, a surface of which is coated with a multilayer barrier coating which includes at least one sublayer of a substantially transparent organic polymer and at least one sublayer of a substantially transparent inorganic material. The device includes a reflective metal layer disposed on the organic EL member opposite to the substrate. The reflective metal layer provides an increased external quantum efficiency of the device. The reflective metal layer and the multilayer barrier coating form a seal around the organic EL member to reduce the degradation of the device due to environmental elements.
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.
Code of Federal Regulations, 2010 CFR
2010-07-01
.... (c) Control device means the air pollution control equipment used to remove particulate matter... air pollution control device. (e) Charge means the addition of iron and steel scrap or other materials... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF...
Code of Federal Regulations, 2014 CFR
2014-07-01
.... (c) Control device means the air pollution control equipment used to remove particulate matter... air pollution control device. (e) Charge means the addition of iron and steel scrap or other materials... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF...
Code of Federal Regulations, 2012 CFR
2012-07-01
.... (c) Control device means the air pollution control equipment used to remove particulate matter... air pollution control device. (e) Charge means the addition of iron and steel scrap or other materials... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF...
Code of Federal Regulations, 2011 CFR
2011-07-01
.... (c) Control device means the air pollution control equipment used to remove particulate matter... air pollution control device. (e) Charge means the addition of iron and steel scrap or other materials... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF...
Code of Federal Regulations, 2013 CFR
2013-07-01
.... (c) Control device means the air pollution control equipment used to remove particulate matter... air pollution control device. (e) Charge means the addition of iron and steel scrap or other materials... Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS (CONTINUED) STANDARDS OF...
1999-11-10
Space Vacuum Epitaxy Center works with industry and government laboratories to develop advanced thin film materials and devices by utilizing the most abundant free resource in orbit: the vacuum of space. SVEC, along with its affiliates, is developing semiconductor mid-IR lasers for environmental sensing and defense applications, high efficiency solar cells for space satellite applications, oxide thin films for computer memory applications, and ultra-hard thin film coatings for wear resistance in micro devices. Performance of these vacuum deposited thin film materials and devices can be enhanced by using the ultra-vacuum of space for which SVEC has developed the Wake Shield Facility---a free flying research platform dedicated to thin film materials development in space.
2000-11-10
Space Vacuum Epitaxy Center works with industry and government laboratories to develop advanced thin film materials and devices by utilizing the most abundant free resource in orbit: the vacuum of space. SVEC, along with its affiliates, is developing semiconductor mid-IR lasers for environmental sensing and defense applications, high efficiency solar cells for space satellite applications, oxide thin films for computer memory applications, and ultra-hard thin film coatings for wear resistance in micro devices. Performance of these vacuum deposited thin film materials and devices can be enhanced by using the ultra-vacuum of space for which SVEC has developed the Wake Shield Facility---a free flying research platform dedicated to thin film materials development in space.
Materials, Processes, and Facile Manufacturing for Bioresorbable Electronics: A Review.
Yu, Xiaowei; Shou, Wan; Mahajan, Bikram K; Huang, Xian; Pan, Heng
2018-05-07
Bioresorbable electronics refer to a new class of advanced electronics that can completely dissolve or disintegrate with environmentally and biologically benign byproducts in water and biofluids. They have provided a solution to the growing electronic waste problem with applications in temporary usage of electronics such as implantable devices and environmental sensors. Bioresorbable materials such as biodegradable polymers, dissolvable conductors, semiconductors, and dielectrics are extensively studied, enabling massive progress of bioresorbable electronic devices. Processing and patterning of these materials are predominantly relying on vacuum-based fabrication methods so far. However, for the purpose of commercialization, nonvacuum, low-cost, and facile manufacturing/printing approaches are the need of the hour. Bioresorbable electronic materials are generally more chemically reactive than conventional electronic materials, which require particular attention in developing the low-cost manufacturing processes in ambient environment. This review focuses on material reactivity, ink availability, printability, and process compatibility for facile manufacturing of bioresorbable electronics. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Advanced Layered Composite Polylaminate Electroactive Actuator and Sensor
NASA Technical Reports Server (NTRS)
Fox, Robert L. (Inventor); Hellbaum, Richard F. (Inventor); Copeland, Benjamin M., Jr. (Inventor); Bryant, Robert G. (Inventor)
2000-01-01
The present invention relates to the mounting of pre-stressed electroactive material in such a manner that large displacement actuators or sensors result. The invention comprises mounting the pre-stressed electroactive material to a support layer. This combination of a pre-stressed electroactive material and support layer may in turn be attached to a mounting surface. The pre-stressed electroactive material may be a ferroelectric, pyroelectric, piezoelectric, or magnetostrictive material. The size, stiffness, mass, and material of the support layer is selected to result in the electroactive device having dynamic response properties, environmental capability characteristics, and the required resilience optimized for a given application. The capacity to connect the support layer to a surface expands the arenas in which the prestressed electroactive device may be used. Application for which the invention may be used include actuators, sensors, or as a component in a pumps, switches, relays, pressure transducers and acoustic devices.
Wu, Yue; Zou, Yan; Yang, Hang; Li, Yaowen; Li, Hongkun; Cui, Chaohua; Li, Yongfang
2017-10-25
Nowadays, most of the solution-processed high-efficiency polymer solar cell (PSC) devices are fabricated by halogenated solvents (such as chlorobenzene, 1,2-dichlorobenzene, chloroform, etc.) which are harmful to people and the environment. Therefore, it is essential to develop high-efficiency PSC devices processed by environmentally friendly solvent processing for their industrialization. In this regard, we report a new alkylthio chain-based conjugated polymer PBDB-TS as donor material for environmentally friendly solvent-processed PSCs. PBDB-TS possesses a low-lying HOMO energy level at -5.42 eV and a good solubility in toluene and o-xylene. By using o-xylene and 1% N-methylpyrrolidone as processing solvent, following by the thermal annealing treatment for PBDB-TS:ITIC blend films, well-developed morphological features, and balanced charge transport properties are observed, leading to a high power conversion efficiency (PCE) of 9.85%, higher than that of the device cast from halogenated solvent (PCE = 9.65%). The results suggest that PBDB-TS is an attractive donor material for nonhalogen solvents-processing PSCs.
Hughes, Gareth; Westmacott, Kelly; Honeychurch, Kevin C.; Crew, Adrian; Pemberton, Roy M.; Hart, John P.
2016-01-01
This review describes recent advances in the fabrication of electrochemical (bio)sensors based on screen-printing technology involving carbon materials and their application in biomedical, agri-food and environmental analyses. It will focus on the various strategies employed in the fabrication of screen-printed (bio)sensors, together with their performance characteristics; the application of these devices for the measurement of selected naturally occurring biomolecules, environmental pollutants and toxins will be discussed. PMID:27690118
NASA Astrophysics Data System (ADS)
Gray, Bonnie L.
2012-04-01
Microfluidics is revolutionizing laboratory methods and biomedical devices, offering new capabilities and instrumentation in multiple areas such as DNA analysis, proteomics, enzymatic analysis, single cell analysis, immunology, point-of-care medicine, personalized medicine, drug delivery, and environmental toxin and pathogen detection. For many applications (e.g., wearable and implantable health monitors, drug delivery devices, and prosthetics) mechanically flexible polymer devices and systems that can conform to the body offer benefits that cannot be achieved using systems based on conventional rigid substrate materials. However, difficulties in implementing active devices and reliable packaging technologies have limited the success of flexible microfluidics. Employing highly compliant materials such as PDMS that are typically employed for prototyping, we review mechanically flexible polymer microfluidic technologies based on free-standing polymer substrates and novel electronic and microfluidic interconnection schemes. Central to these new technologies are hybrid microfabrication methods employing novel nanocomposite polymer materials and devices. We review microfabrication methods using these materials, along with demonstrations of example devices and packaging schemes that employ them. We review these recent developments and place them in the context of the fields of flexible microfluidics and conformable systems, and discuss cross-over applications to conventional rigid-substrate microfluidics.
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...
Electrochromic material and electro-optical device using same
Cogan, Stuart F.; Rauh, R. David
1992-01-01
An oxidatively coloring electrochromic layer of composition M.sub.y CrO.sub.2+x (0.33.ltoreq.y.ltoreq.2.0 and x.ltoreq.2) where M=Li, Na or K with improved transmittance modulation, improved thermal and environmental stability, and improved resistance to degradation in organic liquid and polymeric electrolytes. The M.sub.y CrO.sub.2+x provides complementary optical modulation to cathodically coloring materials in thin-film electrochromic glazings and electrochromic devices employing polymeric Li.sup.+ ion conductors.
Electrochromic material and electro-optical device using same
Cogan, S.F.; Rauh, R.D.
1992-01-14
An oxidatively coloring electrochromic layer of composition M[sub y]CrO[sub 2+x] (0.33[le]y[le]2.0 and x[le]2) where M=Li, Na or K with improved transmittance modulation, improved thermal and environmental stability, and improved resistance to degradation in organic liquid and polymeric electrolytes. The M[sub y]CrO[sub 2+x] provides complementary optical modulation to cathodically coloring materials in thin-film electrochromic glazings and electrochromic devices employing polymeric Li[sup +] ion conductors. 12 figs.
Ali Tahir, Asif; Ullah, Habib; Sudhagar, Pitchaimuthu; Asri Mat Teridi, Mohd; Devadoss, Anitha; Sundaram, Senthilarasu
2016-06-01
Graphene (GR) and its derivatives are promising materials on the horizon of nanotechnology and material science and have attracted a tremendous amount of research interest in recent years. The unique atom-thick 2D structure with sp(2) hybridization and large specific surface area, high thermal conductivity, superior electron mobility, and chemical stability have made GR and its derivatives extremely attractive components for composite materials for solar energy conversion, energy storage, environmental purification, and biosensor applications. This review gives a brief introduction of GR's unique structure, band structure engineering, physical and chemical properties, and recent energy-related progress of GR-based materials in the fields of energy conversion (e.g., photocatalysis, photoelectrochemical water splitting, CO2 reduction, dye-sensitized and organic solar cells, and photosensitizers in photovoltaic devices) and energy storage (batteries, fuel cells, and supercapacitors). The vast coverage of advancements in environmental applications of GR-based materials for photocatalytic degradation of organic pollutants, gas sensing, and removal of heavy-metal ions is presented. Additionally, the use of graphene composites in the biosensing field is discussed. We conclude the review with remarks on the challenges, prospects, and further development of GR-based materials in the exciting fields of energy, environment, and bioscience. © 2016 The Chemical Society of Japan & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Wood-derived materials for green electronics, biological Devices, and energy applications
Hongli Zhu; Wei Luo; Peter N. Ciesielski; Zhiqiang Fang; Junyong Zhu; Gunnar Henriksson; Michael E. Himmel; Liangbing Hu
2016-01-01
With the arising of global climate change and resource shortage, in recent years, increased attention has been paid to environmentally friendly materials. Trees are sustainable and renewable materials, which give us shelter and oxygen and remove carbon dioxide from the atmosphere. Trees are a primary resource that human society depends upon every day, for example,...
Research Progress in MnO2 -Carbon Based Supercapacitor Electrode Materials.
Zhang, Qun-Zheng; Zhang, Dian; Miao, Zong-Cheng; Zhang, Xun-Li; Chou, Shu-Lei
2018-04-30
With the serious impact of fossil fuels on the environment and the rapid development of the global economy, the development of clean and usable energy storage devices has become one of the most important themes of sustainable development in the world today. Supercapacitors are a new type of green energy storage device, with high power density, long cycle life, wide temperature range, and both economic and environmental advantages. In many industries, they have enormous application prospects. Electrode materials are an important factor affecting the performance of supercapacitors. MnO 2 -based materials are widely investigated for supercapacitors because of their high theoretical capacitance, good chemical stability, low cost, and environmental friendliness. To achieve high specific capacitance and high rate capability, the current best solution is to use MnO 2 and carbon composite materials. Herein, MnO 2 -carbon composite as supercapacitor electrode materials is reviewed including the synthesis method and research status in recent years. Finally, the challenges and future development directions of an MnO 2 -carbon based supercapacitor are summarized. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Hansen, O Grøndahl
2008-10-01
Some hospitals in Europe still recommend medical devices that are not made from poly(vinyl chloride) (PVC) mainly because of environmental concerns. Yet, a brand new life cycle analysis that compares a medical device made from PVC with two devices made from alternative plastic materials shows that deselection of PVC is not advisable. This article reports on the latest scientific opinion on the possible risks related to the use of di(2-ethylhexyl) phthalate in medical devices and addresses some of the conclusions of the life cycle analysis.
Wilks, Beth; Morgan, Ruth M; Rose, Neil L
2017-09-01
The use of geoforensic analysis in criminal investigations is continuing to develop, with the diversification of analytical techniques, many of which are semi-automated, facilitating prompt analysis of large sample sets at a relatively low cost. Whilst micro-scale geoforensic analysis has been shown to assist criminal investigations including homicide (Concheri et al., 2011 [1]), wildlife crime (Morgan et al., 2006 [2]), illicit drug distribution (Stanley, 1992 [3]), and burglary (Mildenhall, 2006 [4]), its application to the pressing international security threat posed by Improvised Explosive Devices (IEDs) is yet to be considered. This experimental study simulated an IED supply chain from the sourcing of raw materials through to device emplacement. Mineralogy, quartz grain surface texture analysis (QGSTA) and particle size analysis (PSA) were used to assess whether environmental materials were transferred and subsequently persisted on the different components of three pressure plate IEDs. The research also addressed whether these samples were comprised of material from single or multiple geographical provenances that represented supply chain activity nodes. The simulation demonstrated that material derived from multiple activity nodes, was transferred and persisted on device components. The results from the mineralogy and QGSTA illustrated the value these techniques offer for the analysis of mixed provenance samples. The results from the PSA, which produces a bulk signature of the sample, failed to distinguish multiple provenances. The study also considered how the environmental material recovered could be used to generate information regarding the geographical locations the device had been in contact with, in an intelligence style investigation, and demonstrated that geoforensic analysis has the potential to be of value to international counter-IED efforts. It is a tool that may be used to prevent the distribution of large quantities of devices, by aiding the identification of the geographical location of key activity nodes. Copyright © 2017 The Authors. Published by Elsevier B.V. All rights reserved.
Graphene based 2D-materials for supercapacitors
NASA Astrophysics Data System (ADS)
Palaniselvam, Thangavelu; Baek, Jong-Beom
2015-09-01
Ever-increasing energy demands and the depletion of fossil fuels are compelling humanity toward the development of suitable electrochemical energy conversion and storage devices to attain a more sustainable society with adequate renewable energy and zero environmental pollution. In this regard, supercapacitors are being contemplated as potential energy storage devices to afford cleaner, environmentally friendly energy. Recently, a great deal of attention has been paid to two-dimensional (2D) nanomaterials, including 2D graphene and its inorganic analogues (transition metal double layer hydroxides, chalcogenides, etc), as potential electrodes for the development of supercapacitors with high electrochemical performance. This review provides an overview of the recent progress in using these graphene-based 2D materials as potential electrodes for supercapacitors. In addition, future research trends including notable challenges and opportunities are also discussed.
40 CFR 63.11151 - What definitions apply to this subpart?
Code of Federal Regulations, 2011 CFR
2011-07-01
... the vessel. Control device means air pollution control equipment used to remove PM from a gas stream... of air to reduce the moisture content of the material. Supplemental copper-bearing feed materials and...? 63.11151 Section 63.11151 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR...
40 CFR 63.11151 - What definitions apply to this subpart?
Code of Federal Regulations, 2012 CFR
2012-07-01
... the vessel. Control device means air pollution control equipment used to remove PM from a gas stream... of air to reduce the moisture content of the material. Supplemental copper-bearing feed materials and...? 63.11151 Section 63.11151 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR...
40 CFR 63.11151 - What definitions apply to this subpart?
Code of Federal Regulations, 2013 CFR
2013-07-01
... the vessel. Control device means air pollution control equipment used to remove PM from a gas stream... of air to reduce the moisture content of the material. Supplemental copper-bearing feed materials and...? 63.11151 Section 63.11151 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR...
40 CFR 63.11151 - What definitions apply to this subpart?
Code of Federal Regulations, 2014 CFR
2014-07-01
... the vessel. Control device means air pollution control equipment used to remove PM from a gas stream... of air to reduce the moisture content of the material. Supplemental copper-bearing feed materials and...? 63.11151 Section 63.11151 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR...
40 CFR 63.11151 - What definitions apply to this subpart?
Code of Federal Regulations, 2010 CFR
2010-07-01
... the vessel. Control device means air pollution control equipment used to remove PM from a gas stream... of air to reduce the moisture content of the material. Supplemental copper-bearing feed materials and...? 63.11151 Section 63.11151 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR...
Improved performance of organic solar cells with solution processed hole transport layer
NASA Astrophysics Data System (ADS)
Bhargav, Ranoo; Gairola, S. P.; Patra, Asit; Naqvi, Samya; Dhawan, S. K.
2018-06-01
This work is based on Cobalt Oxide as solution processed, inexpensive and effective hole transport layer (HTL) for efficient organic photovoltaic applications (OPVs). In Organic solar cell (OSC) devices ITO coated glass substrate used as a transparent anode electrode for light incident, HTL material Co3O4 dissolve in DMF solvent deposited on anode electrode, after that active layer material (donor/acceptor) deposited on to HTL and finally Al were deposited by thermal evaporation used as cathode electrode. These devices were fabricated with PCDTBT well known low band gap donor material in OSCs and blended with PC71BM as an acceptor material using simplest device structure ITO/Co3O4/active layer/Al at ambient conditions. The power conversion efficiencies (PCEs) based on Co3O4 and PEDOT:PSS have been achieved to up to 3.21% and 1.47% with PCDTBT respectively. In this study we reported that the devices fabricated with Co3O4 showed better performance as compare to the devices fabricated with well known and most studied solution processed HTL material PEDOT:PSS under identical environmental conditions. The surface morphology of the HTL film was characterized by (AFM). Lastly, we have provided Co3O4 as an efficient hole transport material HTL for solution processed organic photovoltaic applications.
Experimental study of a flexible and environmentally stable electroadhesive device
NASA Astrophysics Data System (ADS)
Guo, J.; Bamber, T.; Singh, J.; Manby, D.; Bingham, P. A.; Justham, L.; Petzing, J.; Penders, J.; Jackson, M.
2017-12-01
Electroadhesion is a promising adhesion mechanism for robotics and material handling applications due to several distinctive advantages it has over existing technologies. These advantages include enhanced adaptability, gentle/flexible handling, reduced complexity, and ultra-low energy consumption. Unstable electroadhesive forces, however, can arise in ambient environments. Electroadhesive devices that can produce stable forces in changing environments are thus desirable. In this study, a flexible and environmentally stable electroadhesive device was designed and manufactured by conformally coating a layer of barium titanate dielectric on a chemically etched thin copper laminate. The results, obtained from an advanced electroadhesive "normal force" testing platform, show that only a relative difference of 5.94% in the normal force direction was observed. This was achieved when the relative humidity changed from 25% to 53%, temperature from 13.7 °C to 32.8 °C, and atmospheric pressure from 999 hPa to 1016.9 hPa. This environmentally stable electroadhesive device may promote the application of the electroadhesion technology.
ERIC Educational Resources Information Center
Consumer Dynamics Inc., Rockville, MD.
This module, one of 25 on vocational education training for careers in environmental health occupations, contains self-instructional materials on calibrating personal air monitoring devices. Following guidelines for students and instructors and an introduction that explains what the student will learn are three lessons: (1) naming each part of the…
A Look Inside Argonne's Center for Nanoscale Materials
Divan, Ralu; Rosenthal, Dan; Rose, Volker; Wai Hla
2018-05-23
At a very small, or "nano" scale, materials behave differently. The study of nanomaterials is much more than miniaturization - scientists are discovering how changes in size change a material's properties. From sunscreen to computer memory, the applications of nanoscale materials research are all around us. Researchers at Argonne's Center for Nanoscale Materials are creating new materials, methods and technologies to address some of the world's greatest challenges in energy security, lightweight but durable materials, high-efficiency lighting, information storage, environmental stewardship and advanced medical devices.
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.
Lee, Gwan-Hyoung; Cui, Xu; Kim, Young Duck; Arefe, Ghidewon; Zhang, Xian; Lee, Chul-Ho; Ye, Fan; Watanabe, Kenji; Taniguchi, Takashi; Kim, Philip; Hone, James
2015-07-28
Emerging two-dimensional (2D) semiconductors such as molybdenum disulfide (MoS2) have been intensively studied because of their novel properties for advanced electronics and optoelectronics. However, 2D materials are by nature sensitive to environmental influences, such as temperature, humidity, adsorbates, and trapped charges in neighboring dielectrics. Therefore, it is crucial to develop device architectures that provide both high performance and long-term stability. Here we report high performance of dual-gated van der Waals (vdW) heterostructure devices in which MoS2 layers are fully encapsulated by hexagonal boron nitride (hBN) and contacts are formed using graphene. The hBN-encapsulation provides excellent protection from environmental factors, resulting in highly stable device performance, even at elevated temperatures. Our measurements also reveal high-quality electrical contacts and reduced hysteresis, leading to high two-terminal carrier mobility (33-151 cm(2) V(-1) s(-1)) and low subthreshold swing (80 mV/dec) at room temperature. Furthermore, adjustment of graphene Fermi level and use of dual gates enable us to separately control contact resistance and threshold voltage. This novel vdW heterostructure device opens up a new way toward fabrication of stable, high-performance devices based on 2D materials.
Mercury-Containing Devices and Demolition
Some items inside residential buildings contain mercury, which poses a persistent and toxic human health and environmental threat. These materials should be carefully salvaged for proper recycling to prevent mercury contamination prior to demolition.
Environmental barrier material for organic light emitting device and method of making
Graff, Gordon L [West Richland, WA; Gross, Mark E [Pasco, WA; Affinito, John D [Kennewick, WA; Shi, Ming-Kun [Richland, WA; Hall, Michael [West Richland, WA; Mast, Eric [Richland, WA
2003-02-18
An encapsulated organic light emitting device. The device includes a first barrier stack comprising at least one first barrier layer and at least one first polymer layer. There is an organic light emitting layer stack adjacent to the first barrier stack. A second barrier stack is adjacent to the organic light emitting layer stack. The second barrier stack has at least one second barrier layer and at least one second polymer layer. A method of making the encapsulated organic light emitting device is also provided.
Environmentally Benign Stab Detonators
DOE Office of Scientific and Technical Information (OSTI.GOV)
Gash, A
2005-12-21
Many energetic systems can be activated via mechanical means. Percussion primers in small caliber ammunition and stab detonators used in medium caliber ammunition are just two examples. Current medium caliber (20-60mm) munitions are detonated through the use of impact sensitive stab detonators. Stab detonators are very sensitive and must be small, as to meet weight and size limitations. A mix of energetic powders, sensitive to mechanical stimulus, is typically used to ignite such devices. Stab detonators are mechanically activated by forcing a firing pin through the closure disc of the device and into the stab initiating mix. Rapid heating causedmore » by mechanically driven compression and friction of the mixture results in its ignition. The rapid decomposition of these materials generates a pressure/temperature pulse that is sufficient to initiate a transfer charge, which has enough output energy to detonate the main charge. This general type of ignition mix is used in a large variety of primers, igniters, and detonators.[1] Common primer mixes, such as NOL-130, are made up of lead styphnate (basic) 40%, lead azide (dextrinated) 20%, barium nitrate 20%, antimony sulfide 15%, and tetrazene 5%.[1] These materials pose acute and chronic toxicity hazards during mixing of the composition and later in the item life cycle after the item has been field functioned. There is an established need to replace these mixes on toxicity, health, and environmental hazard grounds. This effort attempts to demonstrate that environmentally acceptable energetic solgel coated flash metal multilayer nanocomposites can be used to replace current impact initiated devices (IIDs), which have hazardous and toxic components. Successful completion of this project will result in IIDs that include innocuous compounds, have sufficient output energy for initiation, meet current military specifications, are small, cost competitive, and perform as well as or better than current devices. We expect flash metal multilayer and sol-gel to be generic technologies applicable to a wide range of devices, especially in small caliber ammunition and sub-munitions. We will replace the NOL-130 mixture with a nanocomposite that consists of a mechanically robust energetic multilayer foil that has been coated with a sol-gel energetic material. The exothermic reactions are activated in this nanocomposite are the transformation of the multilayer material to its respective intermetallic alloy and the thermite reaction, which is characterized by very high temperatures, a small pressure pulse, and hot particle ejection. The proposed materials and their reaction products consist of, but are not limited to aluminum, nickel, iron, aluminum oxide, titanium, iron oxide and boron. These materials have much more desirable environmental and health characteristics than the NOL-130 composition.« less
Compact high reliability fiber coupled laser diodes for avionics and related applications
NASA Astrophysics Data System (ADS)
Daniel, David R.; Richards, Gordon S.; Janssen, Adrian P.; Turley, Stephen E. H.; Stockton, Thomas E.
1993-04-01
This paper describes a newly developed compact high reliability fiber coupled laser diode which is capable of providing enhanced performance under extreme environmental conditions including a very wide operating temperature range. Careful choice of package materials to minimize thermal and mechanical stress, used with proven manufacturing methods, has resulted in highly stable coupling of the optical fiber pigtail to a high performance MOCVD-grown Multi-Quantum Well laser chip. Electro-optical characteristics over temperature are described together with a demonstration of device stability over a range of environmental conditions. Real time device lifetime data is also presented.
Biodegradable Polymeric Materials in Degradable Electronic Devices
2018-01-01
Biodegradable electronics have great potential to reduce the environmental footprint of devices and enable advanced health monitoring and therapeutic technologies. Complex biodegradable electronics require biodegradable substrates, insulators, conductors, and semiconductors, all of which comprise the fundamental building blocks of devices. This review will survey recent trends in the strategies used to fabricate biodegradable forms of each of these components. Polymers that can disintegrate without full chemical breakdown (type I), as well as those that can be recycled into monomeric and oligomeric building blocks (type II), will be discussed. Type I degradation is typically achieved with engineering and material science based strategies, whereas type II degradation often requires deliberate synthetic approaches. Notably, unconventional degradable linkages capable of maintaining long-range conjugation have been relatively unexplored, yet may enable fully biodegradable conductors and semiconductors with uncompromised electrical properties. While substantial progress has been made in developing degradable device components, the electrical and mechanical properties of these materials must be improved before fully degradable complex electronics can be realized. PMID:29632879
Organic n-type materials for charge transport and charge storage applications.
Stolar, Monika; Baumgartner, Thomas
2013-06-21
Conjugated materials have attracted much attention toward applications in organic electronics in recent years. These organic species offer many advantages as potential replacement for conventional materials (i.e., silicon and metals) in terms of cheap fabrication and environmentally benign devices. While p-type (electron-donating or hole-conducting) materials have been extensively reviewed and researched, their counterpart n-type (electron-accepting or electron-conducting) materials have seen much less popularity despite the greater need for improvement. In addition to developing efficient charge transport materials, it is equally important to provide a means of charge storage, where energy can be used on an on-demand basis. This perspective is focused on discussing a selection of representative n-type materials and the efforts toward improving their charge-transport efficiencies. Additionally, this perspective will also highlight recent organic materials for battery components and the efforts that have been made to improve their environmental appeal.
High-performance green semiconductor devices: materials, designs, and fabrication
NASA Astrophysics Data System (ADS)
Jung, Yei Hwan; Zhang, Huilong; Gong, Shaoqin; Ma, Zhenqiang
2017-06-01
From large industrial computers to non-portable home appliances and finally to light-weight portable gadgets, the rapid evolution of electronics has facilitated our daily pursuits and increased our life comforts. However, these rapid advances have led to a significant decrease in the lifetime of consumer electronics. The serious environmental threat that comes from electronic waste not only involves materials like plastics and heavy metals, but also includes toxic materials like mercury, cadmium, arsenic, and lead, which can leak into the ground and contaminate the water we drink, the food we eat, and the animals that live around us. Furthermore, most electronics are comprised of non-renewable, non-biodegradable, and potentially toxic materials. Difficulties in recycling the increasing amount of electronic waste could eventually lead to permanent environmental pollution. As such, discarded electronics that can naturally degrade over time would reduce recycling challenges and minimize their threat to the environment. This review provides a snapshot of the current developments and challenges of green electronics at the semiconductor device level. It looks at the developments that have been made in an effort to help reduce the accumulation of electronic waste by utilizing unconventional, biodegradable materials as components. While many semiconductors are classified as non-biodegradable, a few biodegradable semiconducting materials exist and are used as electrical components. This review begins with a discussion of biodegradable materials for electronics, followed by designs and processes for the manufacturing of green electronics using different techniques and designs. In the later sections of the review, various examples of biodegradable electrical components, such as sensors, circuits, and batteries, that together can form a functional electronic device, are discussed and new applications using green electronics are reviewed.
A new submarine oil-water separation system
NASA Astrophysics Data System (ADS)
Cai, Wen-Bin; Liu, Bo-Hong
2017-12-01
In order to solve the oil field losses of environmental problems and economic benefit caused by the separation of lifting production liquid to offshore platforms in the current offshore oil production, from the most basic separation principle, a new oil-water separation system has been processed of adsorption and desorption on related materials, achieving high efficiency and separation of oil and water phases. And the submarine oil-water separation device has been designed. The main structure of the device consists of gas-solid phase separation device, period separating device and adsorption device that completed high efficiency separation of oil, gas and water under the adsorption and desorption principle, and the processing capacity of the device is calculated.
Synthesis of nanostructured marcasite FeS2 for energy storage applications
NASA Astrophysics Data System (ADS)
Kaur, Gurpreet; Sharma, Pooja D.; Thakur, Anup; Kumar, Manjeet; Bala, Rajni; Kumar, Akshay
2018-05-01
The synthesis of marcasite FeS2 is of great interest as this area is seldom studied due to its sophisticated synthesis methods. In fulfillment of growing energy demands, there is need of cost effective alternates for energy storage devices. Nanostructured marcasite iron disulfide (FeS2) is a promising candidate as anode material for energy storage devices. FeS2 exist in many phases out of which marcasite and pyrite are best suitable for energy storage applications. Purity of the phase is a big challenge for its application oriented use. Pure marcasite (FeS2) has been synthesized by low cost, environmentally friendly hydrothermal route. The synthesized material has been characterized by X-ray Diffraction (XRD). Cyclic voltammetry results show the significant electrochemical performance of marcasite. This work purposes a vision to develop marcasite based electrode material for energy storage devices.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhao, Wei; Rovore, Thomas; Weerawarne, Darshana
2015-06-02
While conformal and wearable devices have become one of the most desired formats for printable electronics, it is challenging to establish a scalable process that produces stable conductive patterns but also uses substrates compatible with widely available wearable materials. Here, we describe findings of an investigation of a nanoalloy ink printed and pulsed laser sintered conductive patterns as flexible functional devices with enhanced stability and materials compatibility. While nanoparticle inks are desired for printable electronics, almost all existing nanoparticle inks are based on single-metal component, which, as an electronic element, is limited by its inherent stabilities of the metal suchmore » as propensity of metal oxidation and mobility of metal ions, especially in sintering processes. The work here has demonstrated the first example in exploiting plasmonic coupling of nanoalloys and pulsed-laser energy with controllable thermal penetration. The experimental and theoretical results have revealed clear correlation between the pulsed laser parameters and the nanoalloy structural characteristics. The superior performance of the resulting flexible sensor device, upon imparting nanostructured sensing materials, for detecting volatile organic compounds has significant implications to developing stable and wearable sensors for monitoring environmental pollutants and breath biomarkers. This simple “nanoalloy printing 'laser sintering' nanostructure printing” process is entirely general to many different sensor devices and nanostructured sensing materials, enabling the ability to easily construct sophisticated sensor array.« less
Zhao, Wei; Rovere, Thomas; Weerawarne, Darshana; Osterhoudt, Gavin; Kang, Ning; Joseph, Pharrah; Luo, Jin; Shim, Bonggu; Poliks, Mark; Zhong, Chuan-Jian
2015-06-23
While conformal and wearable devices have become one of the most desired formats for printable electronics, it is challenging to establish a scalable process that produces stable conductive patterns but also uses substrates compatible with widely available wearable materials. Here, we describe findings of an investigation of a nanoalloy ink printed and pulsed-laser sintered conductive patterns as flexible functional devices with enhanced stability and materials compatibility. While nanoparticle inks are desired for printable electronics, almost all existing nanoparticle inks are based on single-metal component, which, as an electronic element, is limited by its inherent stabilities of the metal such as propensity of metal oxidation and mobility of metal ions, especially in sintering processes. The work here has demonstrated the first example in exploiting plasmonic coupling of nanoalloys and pulsed-laser energy with controllable thermal penetration. The experimental and theoretical results have revealed clear correlation between the pulsed laser parameters and the nanoalloy structural characteristics. The superior performance of the resulting flexible sensor device, upon imparting nanostructured sensing materials, for detecting volatile organic compounds has significant implications to developing stable and wearable sensors for monitoring environmental pollutants and breath biomarkers. This simple "nanoalloy printing-laser sintering-nanostructure printing" process is entirely general to many different sensor devices and nanostructured sensing materials, enabling the ability to easily construct sophisticated sensor array.
PECASE: Nanostructure Hybrid Organic/Inorganic Materials for Active Opto-Electronic Devices
2011-01-03
FWHM= 30 nm), green-emitting core–shell material ( 4 nm in diameter) suitable for QD- LED display applications (Figure 1b). An alloyed material for...electroluminescence (EL) that can be of use in fields as diverse as optical communications, spectroscopy, and environmental and industrial sensing. The RC structure...variety of QD size distributions (of Gaussian size profile). Such QD monoalyers have already been utilized in a number of thin-film applications , QD
Fixture for environmental exposure of structural materials under compression load
NASA Technical Reports Server (NTRS)
Clark, R. K.; Lisagor, W. B. (Inventor)
1983-01-01
A device for stressing a deformable material specimen consists of top plate and a bottom plate sandwiching a guide cylinder. The specimen is positioned on the bottom plate and attached to a load piston. Force is applied through the top plate into the guide cylinder. Once the specimen is loaded, the stress is maintained by tightening tie bolt nuts.
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
Micro- and nanofluidic systems in devices for biological, medical and environmental research
NASA Astrophysics Data System (ADS)
Evstrapov, A. A.
2017-11-01
The use of micro- and nanofluidic systems in modern analytical instruments allow you to implement a number of unique opportunities and achieve ultra-high measurement sensitivity. The possibility of manipulation of the individual biological objects (cells, bacteria, viruses, proteins, nucleic acids) in a liquid medium caused the development of devices on microchip platform for methods: chromatographic and electrophoretic analyzes; polymerase chain reaction; sequencing of nucleic acids; immunoassay; cytometric studies. Development of micro and nano fabrication technologies, materials science, surface chemistry, analytical chemistry, cell engineering have led to the creation of a unique systems such as “lab-on-a-chip”, “human-on-a-chip” and other. This article discusses common in microfluidics materials and methods of making functional structures. Examples of integration of nanoscale structures in microfluidic devices for the implementation of new features and improve the technical characteristics of devices and systems are shown.
An overview of self-switching diode rectifiers using green materials
NASA Astrophysics Data System (ADS)
Kasjoo, Shahrir Rizal; Zailan, Zarimawaty; Zakaria, Nor Farhani; Isa, Muammar Mohamad; Arshad, Mohd Khairuddin Md; Taking, Sanna
2017-09-01
A unipolar two-terminal nanodevice, known as the self-switching diode (SSD), has recently been demonstrated as a room-temperature rectifier at microwave and terahertz frequencies due to its nonlinear current-voltage characteristic. The planar architecture of SSD not only makes the fabrication process of the device faster, simpler and at a lower cost when compared with other rectifying diodes, but also allows the use of various materials to realize and fabricate SSDs. This includes the utilization of `green' materials such as organic and graphene thin films for environmental sustainability. This paper reviews the properties of current `green' SSD rectifiers with respect to their operating frequencies and rectifying performances, including responsivity and noise-equivalent power of the devices, along with the applications.
Microfibrous metallic cloth for acoustic isolation of a MEMS gyroscope
NASA Astrophysics Data System (ADS)
Dean, Robert; Burch, Nesha; Black, Meagan; Beal, Aubrey; Flowers, George
2011-04-01
The response of a MEMS device that is exposed to a harsh environment may range from an increased noise floor to a completely erroneous output to temporary or even permanent device failure. One such harsh environment is high power acoustic energy possessing high frequency components. This type of environment sometimes occurs in small aerospace vehicles. In this type of operating environment, high frequency acoustic energy can be transferred to a MEMS gyroscope die through the device packaging. If the acoustic noise possesses a sufficiently strong component at the resonant frequency of the gyroscope, it will overexcite the motion of the proof mass, resulting in the deleterious effect of corrupted angular rate measurement. Therefore if the device or system packaging can be improved to sufficiently isolate the gyroscope die from environmental acoustic energy, the sensor may find new applications in this type of harsh environment. This research effort explored the use of microfibrous metallic cloth for isolating the gyroscope die from environmental acoustic excitation. Microfibrous cloth is a composite of fused, intermingled metal fibers and has a variety of typical uses involving chemical processing applications and filtering. Specifically, this research consisted of experimental evaluations of multiple layers of packed microfibrous cloth composed of sintered nickel material. The packed cloth was used to provide acoustic isolation for a test MEMS gyroscope, the Analog Devices ADXRS300. The results of this investigation revealed that the intermingling of the various fibers of the metallic cloth provided a significant contact area between the fiber strands and voids, which enhanced the acoustic damping of the material. As a result, the nickel cloth was discovered to be an effective acoustic isolation material for this particular MEMS gyroscope.
Dye Wastewater Cleanup by Graphene Composite Paper for Tailorable Supercapacitors.
Yu, Dandan; Wang, Hua; Yang, Jie; Niu, Zhiqiang; Lu, Huiting; Yang, Yun; Cheng, Liwei; Guo, Lin
2017-06-28
Currently, the energy crisis and environmental pollution are two critical challenges confronted by humans. The development of smart strategies to address the above-mentioned issues simultaneously is significant. As the main accomplices for water pollution, several kinds of organic dyes with intrinsic redox functional groups such as phenothiazines derivatives, anthraquinone, and indigoid dyes are potential candidates for the replacement of the conventional pseudocapacitive materials. In this work, three typical organic dyes can be efficiently removed by a facile adsorption procedure using reduced graphene oxide coated cellulose fiber (rGO@CF) paper. Flexible supercapacitors based on dye/rGO@CF electrodes exhibit excellent electrochemical performances that are superior to or comparable with those of conventional pseudocapacitive materials based devices, presenting a new type of promising electrode materials. Moreover, benefiting from the high flexibility and considerable mechanical strength of the graphene composite paper, the operating potential and capacitance of the devices can be easily adjusted by tailoring the hybrid electrodes into different specific shapes followed by rational integrating. The smart design of these dye/rGO@CF paper based electrodes shows that energy storage and environmental remediation can be achieved simultaneously.
Sensor devices comprising field-structured composites
Martin, James E.; Hughes, Robert C.; Anderson, Robert A.
2001-02-27
A new class of sensor devices comprising field-structured conducting composites comprising a textured distribution of conducting magnetic particles is disclosed. The conducting properties of such field-structured materials can be precisely controlled during fabrication so as to exhibit a large change in electrical conductivity when subject to any environmental influence which changes the relative volume fraction. Influences which can be so detected include stress, strain, shear, temperature change, humidity, magnetic field, electromagnetic radiation, and the presence or absence of certain chemicals. This behavior can be made the basis for a wide variety of sensor devices.
Development of an elution device for ViroCap virus filters.
Fagnant, Christine Susan; Toles, Matthew; Zhou, Nicolette Angela; Powell, Jacob; Adolphsen, John; Guan, Yifei; Ockerman, Byron; Shirai, Jeffry Hiroshi; Boyle, David S; Novosselov, Igor; Meschke, John Scott
2017-10-19
Environmental surveillance of waterborne pathogens is vital for monitoring the spread of diseases, and electropositive filters are frequently used for sampling wastewater and wastewater-impacted surface water. Viruses adsorbed to electropositive filters require elution prior to detection or quantification. Elution is typically facilitated by a peristaltic pump, although this requires a significant startup cost and does not include biosafety or cross-contamination considerations. These factors may pose a barrier for low-resource laboratories that aim to conduct environmental surveillance of viruses. The objective of this study was to develop a biologically enclosed, manually powered, low-cost device for effectively eluting from electropositive ViroCap™ virus filters. The elution device described here utilizes a non-electric bilge pump, instead of an electric peristaltic pump or a positive pressure vessel. The elution device also fully encloses liquids and aerosols that could contain biological organisms, thereby increasing biosafety. Moreover, all elution device components that are used in the biosafety cabinet are autoclavable, reducing cross-contamination potential. This device reduces costs of materials while maintaining convenience in terms of size and weight. With this new device, there is little sample volume loss due to device inefficiency, similar virus yields were demonstrated during seeded studies with poliovirus type 1, and the time to elute filters is similar to that required with the peristaltic pump. The efforts described here resulted in a novel, low-cost, manually powered elution device that can facilitate environmental surveillance of pathogens through effective virus recovery from ViroCap filters while maintaining the potential for adaptability to other cartridge filters.
High-performance green flexible electronics based on biodegradable cellulose nanofibril paper
Jung, Yei Hwan; Chang, Tzu-Hsuan; Zhang, Huilong; Yao, Chunhua; Zheng, Qifeng; Yang, Vina W.; Mi, Hongyi; Kim, Munho; Cho, Sang June; Park, Dong-Wook; Jiang, Hao; Lee, Juhwan; Qiu, Yijie; Zhou, Weidong; Cai, Zhiyong; Gong, Shaoqin; Ma, Zhenqiang
2015-01-01
Today's consumer electronics, such as cell phones, tablets and other portable electronic devices, are typically made of non-renewable, non-biodegradable, and sometimes potentially toxic (for example, gallium arsenide) materials. These consumer electronics are frequently upgraded or discarded, leading to serious environmental contamination. Thus, electronic systems consisting of renewable and biodegradable materials and minimal amount of potentially toxic materials are desirable. Here we report high-performance flexible microwave and digital electronics that consume the smallest amount of potentially toxic materials on biobased, biodegradable and flexible cellulose nanofibril papers. Furthermore, we demonstrate gallium arsenide microwave devices, the consumer wireless workhorse, in a transferrable thin-film form. Successful fabrication of key electrical components on the flexible cellulose nanofibril paper with comparable performance to their rigid counterparts and clear demonstration of fungal biodegradation of the cellulose-nanofibril-based electronics suggest that it is feasible to fabricate high-performance flexible electronics using ecofriendly materials. PMID:26006731
High-performance green flexible electronics based on biodegradable cellulose nanofibril paper.
Jung, Yei Hwan; Chang, Tzu-Hsuan; Zhang, Huilong; Yao, Chunhua; Zheng, Qifeng; Yang, Vina W; Mi, Hongyi; Kim, Munho; Cho, Sang June; Park, Dong-Wook; Jiang, Hao; Lee, Juhwan; Qiu, Yijie; Zhou, Weidong; Cai, Zhiyong; Gong, Shaoqin; Ma, Zhenqiang
2015-05-26
Today's consumer electronics, such as cell phones, tablets and other portable electronic devices, are typically made of non-renewable, non-biodegradable, and sometimes potentially toxic (for example, gallium arsenide) materials. These consumer electronics are frequently upgraded or discarded, leading to serious environmental contamination. Thus, electronic systems consisting of renewable and biodegradable materials and minimal amount of potentially toxic materials are desirable. Here we report high-performance flexible microwave and digital electronics that consume the smallest amount of potentially toxic materials on biobased, biodegradable and flexible cellulose nanofibril papers. Furthermore, we demonstrate gallium arsenide microwave devices, the consumer wireless workhorse, in a transferrable thin-film form. Successful fabrication of key electrical components on the flexible cellulose nanofibril paper with comparable performance to their rigid counterparts and clear demonstration of fungal biodegradation of the cellulose-nanofibril-based electronics suggest that it is feasible to fabricate high-performance flexible electronics using ecofriendly materials.
High-performance green flexible electronics based on biodegradable cellulose nanofibril paper
NASA Astrophysics Data System (ADS)
Jung, Yei Hwan; Chang, Tzu-Hsuan; Zhang, Huilong; Yao, Chunhua; Zheng, Qifeng; Yang, Vina W.; Mi, Hongyi; Kim, Munho; Cho, Sang June; Park, Dong-Wook; Jiang, Hao; Lee, Juhwan; Qiu, Yijie; Zhou, Weidong; Cai, Zhiyong; Gong, Shaoqin; Ma, Zhenqiang
2015-05-01
Today's consumer electronics, such as cell phones, tablets and other portable electronic devices, are typically made of non-renewable, non-biodegradable, and sometimes potentially toxic (for example, gallium arsenide) materials. These consumer electronics are frequently upgraded or discarded, leading to serious environmental contamination. Thus, electronic systems consisting of renewable and biodegradable materials and minimal amount of potentially toxic materials are desirable. Here we report high-performance flexible microwave and digital electronics that consume the smallest amount of potentially toxic materials on biobased, biodegradable and flexible cellulose nanofibril papers. Furthermore, we demonstrate gallium arsenide microwave devices, the consumer wireless workhorse, in a transferrable thin-film form. Successful fabrication of key electrical components on the flexible cellulose nanofibril paper with comparable performance to their rigid counterparts and clear demonstration of fungal biodegradation of the cellulose-nanofibril-based electronics suggest that it is feasible to fabricate high-performance flexible electronics using ecofriendly materials.
Minimizing material damage using low temperature irradiation
NASA Astrophysics Data System (ADS)
Craven, E.; Hasanain, F.; Winters, M.
2012-08-01
Scientific advancements in healthcare driven both by technological breakthroughs and an aging and increasingly obese population have lead to a changing medical device market. Complex products and devices are being developed to meet the demands of leading edge medical procedures. Specialized materials in these medical devices, including pharmaceuticals and biologics as well as exotic polymers present a challenge for radiation sterilization as many of these components cannot withstand conventional irradiation methods. The irradiation of materials at dry ice temperatures has emerged as a technique that can be used to decrease the radiation sensitivity of materials. The purpose of this study is to examine the effect of low temperature irradiation on a variety of polymer materials, and over a range of temperatures from 0 °C down to -80 °C. The effectiveness of microbial kill is also investigated under each of these conditions. The results of the study show that the effect of low temperature irradiation is material dependent and can alter the balance between crosslinking and chain scission of the polymer. Low temperatures also increase the dose required to achieve an equivalent microbiological kill, therefore dose setting exercises must be performed under the environmental conditions of use.
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...
Printed environmentally friendly supercapacitors with ionic liquid electrolytes on paper
NASA Astrophysics Data System (ADS)
Pettersson, F.; Keskinen, J.; Remonen, T.; von Hertzen, L.; Jansson, E.; Tappura, K.; Zhang, Y.; Wilén, C.-E.; Österbacka, R.
2014-12-01
Environmentally friendly supercapacitors are fabricated using commercial grade aluminum coated paper as a substrate and symmetrical activated carbon electrodes as large area electrodes. Different choline chloride-based eutectic solvents are used as electrolyte. These are inexpensive, environmentally friendly and have a larger operating window compared to that of water electrolytes. As the entire device is printed and the materials used are inexpensive, both small- and large-area power sources can be fabricated to be used in cheap, disposable and recyclable devices. Supercapacitors with different eutectic solvents are measured using cyclic charge-discharge and impedance spectroscopy measurements and compared to one widely used and one "green" imidazolium ionic liquid; EMIM:TFSI and EcoEng 212™, respectively. A mixture of ethylene glycol and choline chloride, Glyceline™, show the highest capacitance and power densities of the electrolytes being tested, including the imidazolium alternatives.
A hybrid life cycle inventory of nano-scale semiconductor manufacturing.
Krishnan, Nikhil; Boyd, Sarah; Somani, Ajay; Raoux, Sebastien; Clark, Daniel; Dornfeld, David
2008-04-15
The manufacturing of modern semiconductor devices involves a complex set of nanoscale fabrication processes that are energy and resource intensive, and generate significant waste. It is important to understand and reduce the environmental impacts of semiconductor manufacturing because these devices are ubiquitous components in electronics. Furthermore, the fabrication processes used in the semiconductor industry are finding increasing application in other products, such as microelectromechanical systems (MEMS), flat panel displays, and photovoltaics. In this work we develop a library of typical gate-to-gate materials and energy requirements, as well as emissions associated with a complete set of fabrication process models used in manufacturing a modern microprocessor. In addition, we evaluate upstream energy requirements associated with chemicals and materials using both existing process life cycle assessment (LCA) databases and an economic input-output (EIO) model. The result is a comprehensive data set and methodology that may be used to estimate and improve the environmental performance of a broad range of electronics and other emerging applications that involve nano and micro fabrication.
Thermoelectricity for future sustainable energy technologies
NASA Astrophysics Data System (ADS)
Weidenkaff, Anke
2017-07-01
Thermoelectricity is a general term for a number of effects describing the direct interconversion of heat and electricity. Thermoelectric devices are therefore promising, environmental-friendly alternatives to conventional power generators or cooling units. Since the mid-90s, research on thermoelectric properties and their applications has steadily increased. In the course of years, the development of high-temperature resistant TE materials and devices has emerged as one of the main areas of interest focusing both on basic research and practical applications. A wide range of innovative and cost-efficient material classes has been studied and their properties improved. This has also led to advances in synthesis and metrology. The paper starts out with thermoelectric history, basic effects underlying thermoelectric conversion and selected examples of application. The main part focuses on thermoelectric materials including an outline of the design rules, a review on the most common materials and the feasibility of improved future high-temperature thermoelectric converters.
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.
NASA Astrophysics Data System (ADS)
List-Kratochvil, Emil J. W.
2016-09-01
Comfortable, wearable sensors and computers will enhance every person's awareness of his or her health condition, environment, chemical pollutants, potential hazards, and information of interest. In agriculture and in the food industry there is a need for a constant control of the condition and needs of plants, animals, and farm products. Yet many of these applications depend upon the development of novel, cheap devices and sensors that are easy to implement and to integrate. Organic semiconductors as well as several inorganic materials and hybrid material systems have proven to combine a number of intriguing optical and electronic properties with simple processing methods. As it will be reviewed in this contribution, these materials are believed to find their application in printed electronic devices allowing for the development of smart disposable devices in food-, health-, and environmental monitoring, diagnostics and control, possibly integrated into arrays of sensor elements for multi-parameter detection. In this contribution we review past and recent achievements in the field. Followed by a brief introduction, we will focus on two topics being on the agenda recently: a) the use of electrolyte-gated organic field-effect transistor (EGOFET) and ion-selective membrane based sensors for in-situ sensing of ions and biological substances and b) the development of hybrid material based resistive switches and their integration into fully functional, printed hybrid crossbar sensor array structures.
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.
Arduini, Fabiana; Cinti, Stefano; Scognamiglio, Viviana; Moscone, Danila; Palleschi, Giuseppe
2017-03-22
Through the years, scientists have developed cutting-edge technologies to make (bio)sensors more convenient for environmental analytical purposes. Technological advancements in the fields of material science, rational design, microfluidics, and sensor printing, have radically shaped biosensor technology, which is even more evident in the continuous development of sensing systems for the monitoring of hazardous chemicals. These efforts will be crucial in solving some of the problems constraining biosensors to reach real environmental applications, such as continuous analyses in field by means of multi-analyte portable devices. This review (with 203 refs.) covers the progress between 2010 and 2015 in the field of technologies enabling biosensor applications in environmental analysis, including i) printing technology, ii) nanomaterial technology, iii) nanomotors, iv) biomimetic design, and (v) microfluidics. Next section describes futuristic cutting-edge technologies that are gaining momentum in recent years, which furnish highly innovative aspects to biosensing devices. Copyright © 2016 Elsevier B.V. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Rohlman, Diana; Syron, Laura; Hobbie, Kevin
In west Eugene (Oregon), community research indicates residents are disproportionately exposed to industrial air pollution and exhibit increased asthma incidence. In Carroll County (Ohio), recent increases in unconventional natural gas drilling sparked air quality concerns. These community concerns led to the development of a prototype mobile device to measure personal chemical exposure, location, and respiratory function. Working directly with the environmental justice (EJ) communities, the prototype was developed to (1) meet the needs of the community and; (2) evaluate the use in EJ communities. The prototype was evaluated in 3 community focus groups (n=25) to obtain feedback on the prototypemore » and feasibility study design to evaluate the efficacy of the device to address community concerns. Focus groups were recorded and qualitatively analyzed with discrete feedback tabulated for further refinement. The prototype was improved by community feedback resulting in 8 alterations/additions to software and instructional materials. Overall, focus group participants were supportive of the device and believed it would be a useful environmental health tool. The use of focus groups ensured that community members were engaged in the research design and development of a novel environmental health tool. We found that community-based research strategies resulted in a refined device as well as relevant research questions, specific to the EJ community needs and concerns.« less
Rohlman, Diana; Syron, Laura; Hobbie, Kevin; ...
2015-08-15
In west Eugene (Oregon), community research indicates residents are disproportionately exposed to industrial air pollution and exhibit increased asthma incidence. In Carroll County (Ohio), recent increases in unconventional natural gas drilling sparked air quality concerns. These community concerns led to the development of a prototype mobile device to measure personal chemical exposure, location, and respiratory function. Working directly with the environmental justice (EJ) communities, the prototype was developed to (1) meet the needs of the community and; (2) evaluate the use in EJ communities. The prototype was evaluated in 3 community focus groups (n=25) to obtain feedback on the prototypemore » and feasibility study design to evaluate the efficacy of the device to address community concerns. Focus groups were recorded and qualitatively analyzed with discrete feedback tabulated for further refinement. The prototype was improved by community feedback resulting in 8 alterations/additions to software and instructional materials. Overall, focus group participants were supportive of the device and believed it would be a useful environmental health tool. The use of focus groups ensured that community members were engaged in the research design and development of a novel environmental health tool. We found that community-based research strategies resulted in a refined device as well as relevant research questions, specific to the EJ community needs and concerns.« less
Nanostructured mesoporous materials for lithium-ion battery applications
NASA Astrophysics Data System (ADS)
Balaya, P.; Saravanan, K.; Hariharan, S.; Ramar, V.; Lee, H. S.; Kuezma, M.; Devaraj, S.; Nagaraju, D. H.; Ananthanarayanan, K.; Mason, C. W.
2011-06-01
The Energy crisis happens to be one of the greatest challenges we are facing today. In this view, much effort has been made in developing new, cost effective, environmentally friendly energy conversion and storage devices. The performance of such devices is fundamentally related to material properties. Hence, innovative materials engineering is important in solving the energy crisis problem. One such innovation in materials engineering is porous materials for energy storage. Porous electrode materials for lithium-ion batteries (LIBs) offer a high degree of electrolyte-electrode wettability, thus enhancing the electrochemical activity within the material. Among the porous materials, mesoporous materials draw special attention, owing to shorter diffusion lengths for Li+ and electronic movement. Nanostructured mesoporous materials also offer better packing density compared to their nanostructured counterparts such as nanopowders, nanowires, nanotubes etc., thus opening a window for developing electrode materials with high volumetric energy densities. This would directly translate into a scenario of building batteries which are much lighter than today's commercial LIBs. In this article, the authors present a simple, soft template approach for preparing both cathode and anode materials with high packing density for LIBs. The impact of porosity on the electrochemical storage performance is highlighted.
40 CFR 63.1042 - Standards-Separator fixed roof.
Code of Federal Regulations, 2010 CFR
2010-07-01
... 40 Protection of Environment 10 2010-07-01 2010-07-01 false Standards-Separator fixed roof. 63.1042 Section 63.1042 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) AIR PROGRAMS..., ignitable, explosive, reactive, or hazardous materials. (3) Opening of a safety device, as defined in § 63...
Toward Environmentally Robust Organic Electronics: Approaches and Applications.
Lee, Eun Kwang; Lee, Moo Yeol; Park, Cheol Hee; Lee, Hae Rang; Oh, Joon Hak
2017-11-01
Recent interest in flexible electronics has led to a paradigm shift in consumer electronics, and the emergent development of stretchable and wearable electronics is opening a new spectrum of ubiquitous applications for electronics. Organic electronic materials, such as π-conjugated small molecules and polymers, are highly suitable for use in low-cost wearable electronic devices, and their charge-carrier mobilities have now exceeded that of amorphous silicon. However, their commercialization is minimal, mainly because of weaknesses in terms of operational stability, long-term stability under ambient conditions, and chemical stability related to fabrication processes. Recently, however, many attempts have been made to overcome such instabilities of organic electronic materials. Here, an overview is provided of the strategies developed for environmentally robust organic electronics to overcome the detrimental effects of various critical factors such as oxygen, water, chemicals, heat, and light. Additionally, molecular design approaches to π-conjugated small molecules and polymers that are highly stable under ambient and harsh conditions are explored; such materials will circumvent the need for encapsulation and provide a greater degree of freedom using simple solution-based device-fabrication techniques. Applications that are made possible through these strategies are highlighted. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
NASA Astrophysics Data System (ADS)
Almuslem, A. S.; Hanna, A. N.; Yapici, T.; Wehbe, N.; Diallo, E. M.; Kutbee, A. T.; Bahabry, R. R.; Hussain, M. M.
2017-02-01
In the recent past, with the advent of transient electronics for mostly implantable and secured electronic applications, the whole field effect transistor structure has been dissolved in a variety of chemicals. Here, we show simple water soluble nano-scale (sub-10 nm) germanium oxide (GeO2) as the dissolvable component to remove the functional structures of metal oxide semiconductor devices and then reuse the expensive germanium substrate again for functional device fabrication. This way, in addition to transiency, we also show an environmentally friendly manufacturing process for a complementary metal oxide semiconductor (CMOS) technology. Every year, trillions of complementary metal oxide semiconductor (CMOS) electronics are manufactured and billions are disposed, which extend the harmful impact to our environment. Therefore, this is a key study to show a pragmatic approach for water soluble high performance electronics for environmentally friendly manufacturing and bioresorbable electronic applications.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Crowther, M.A.; Moskowitz, P.D.
1981-07-01
Sample analyses and detailed documentation are presented for a Reference Material System (RMS) to estimate health and environmental risks of different material cycles and energy systems. Data inputs described include: end-use material demands, efficiency coefficients, environmental emission coefficients, fuel demand coefficients, labor productivity estimates, and occupational health and safety coefficients. Application of this model permits analysts to estimate fuel use (e.g., Btu), occupational risk (e.g., fatalities), and environmental emissions (e.g., sulfur oxide) for specific material trajectories or complete energy systems. Model uncertainty is quantitatively defined by presenting a range of estimates for each data input. Systematic uncertainty not quantified relatesmore » to the boundaries chosen for analysis and reference system specification. Although the RMS can be used to analyze material system impacts for many different energy technologies, it was specifically used to examine the health and environmental risks of producing the following four types of photovoltaic devices: silicon n/p single-crystal cells produced by a Czochralski process; silicon metal/insulator/semiconductor (MIS) cells produced by a ribbon-growing process; cadmium sulfide/copper sulfide backwall cells produced by a spray deposition process; and gallium arsenide cells with 500X concentrator produced by a modified Czochralski process. Emission coefficients for particulates, sulfur dioxide and nitrogen dioxide; solid waste; total suspended solids in water; and, where applicable, air and solid waste residuals for arsenic, cadmium, gallium, and silicon are examined and presented. Where data are available the coefficients for particulates, sulfur oxides, and nitrogen oxides include both process and on-site fuel-burning emissions.« less
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.
Advances in microfluidic devices made from thermoplastics used in cell biology and analyses.
Gencturk, Elif; Mutlu, Senol; Ulgen, Kutlu O
2017-09-01
Silicon and glass were the main fabrication materials of microfluidic devices, however, plastics are on the rise in the past few years. Thermoplastic materials have recently been used to fabricate microfluidic platforms to perform experiments on cellular studies or environmental monitoring, with low cost disposable devices. This review describes the present state of the development and applications of microfluidic systems used in cell biology and analyses since the year 2000. Cultivation, separation/isolation, detection and analysis, and reaction studies are extensively discussed, considering only microorganisms (bacteria, yeast, fungi, zebra fish, etc.) and mammalian cell related studies in the microfluidic platforms. The advantages/disadvantages, fabrication methods, dimensions, and the purpose of creating the desired system are explained in detail. An important conclusion of this review is that these microfluidic platforms are still open for research and development, and solutions need to be found for each case separately.
Qi, Ruijie; Nie, Jinhui; Liu, Mingyang; Xia, Mengyang; Lu, Xianmao
2018-04-26
Stretchable energy storage devices are of great importance for the viable applications of wearable/stretchable electronics. Studies on stretchable energy storage devices, especially supercapacitors (SCs), have shown encouraging progress. However, challenges still remain in the pursuit of high specific capacitances and facile fabrication methods. Herein, we report a modular materials fabrication and assembly process for stretchable SCs. With a V2O5/PEDOT composite as the active material, the resulting stretchable SCs exhibited high areal specific capacitances up to 240 mF cm-2 and good capacitance retention at a strain of 50%. To demonstrate the facile assembly process, a stretchable wristband was fabricated by simply assembling SC cells in series to deliver a voltage higher than 2 V. Charging the wristband with a triboelectric nanogenerator (TENG) to light an LED was further demonstrated, indicating the potential to integrate our SCs with environmental energy harvesters for self-powered stretchable devices.
NASA Astrophysics Data System (ADS)
Magnacca, Giuliana; Guerretta, Federico; Vizintin, Alen; Benzi, Paola; Valsania, Maria C.; Nisticò, Roberto
2018-01-01
Chitin (a biopolymer obtained from shellfish industry) was used as precursor for the production of biochars obtained via pyrolysis treatments performed at mild conditions (in the 290-540 °C range). Biochars were physicochemical characterized in order to evaluate the pyrolysis-induced effects in terms of both functional groups and material structure. Moreover, such carbonaceous materials were tested as adsorbent substrates for the removal of target molecules from aqueous environment as well as in solid-gas experiments, to measure the adsorption capacities and selectivity toward CO2. Lastly, biochars were also investigated as possible cathode materials in sustainable and low-cost electrochemical energy storage devices, such as lithium-sulphur (Li-S) batteries. Interestingly, experimental results evidenced that such chitin-derived biochars obtained via pyrolysis at mild conditions are sustainable, low-cost and easy scalable alternative materials suitable for both environmental and energetic applications.
Biopolymer-based strategies in the design of smart medical devices and artificial organs.
Altomare, Lina; Bonetti, Lorenzo; Campiglio, Chiara E; De Nardo, Luigi; Draghi, Lorenza; Tana, Francesca; Farè, Silvia
2018-06-01
Advances in regenerative medicine and in modern biomedical therapies are fast evolving and set goals causing an upheaval in the field of materials science. This review discusses recent developments involving the use of biopolymers as smart materials, in terms of material properties and stimulus-responsive behavior, in the presence of environmental physico-chemical changes. An overview on the transformations that can be triggered in natural-based polymeric systems (sol-gel transition, polymer relaxation, cross-linking, and swelling) is presented, with specific focus on the benefits these materials can provide in biomedical applications.
Nanostructured manganese oxide thin films as electrode material for supercapacitors
NASA Astrophysics Data System (ADS)
Xia, Hui; Lai, Man On; Lu, Li
2011-01-01
Electrochemical capacitors, also called supercapacitors, are alternative energy storage devices, particularly for applications requiring high power densities. Recently, manganese oxides have been extensively evaluated as electrode materials for supercapacitors due to their low cost, environmental benignity, and promising supercapacitive performance. In order to maximize the utilization of manganese oxides as the electrode material for the supercapacitors and improve their supercapacitive performance, the nanostructured manganese oxides have therefore been developed. This paper reviews the synthesis of the nanostructured manganese oxide thin films by different methods and the supercapacitive performance of different nanostructures.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Demuth, Scott F.; Trahan, Alexis Chanel
2017-06-26
DIV of facility layout, material flows, and other information provided in the DIQ. Material accountancy through an annual PIV and a number of interim inventory verifications, including UF6 cylinder identification and counting, NDA of cylinders, and DA on a sample collection of UF6. Application of C/S technologies utilizing seals and tamper-indicating devices (TIDs) on cylinders, containers, storage rooms, and IAEA instrumentation to provide continuity of knowledge between inspection. Verification of the absence of undeclared material and operations, especially HEU production, through SNRIs, LFUA of cascade halls, and environmental swipe sampling
Crockett, Michael P.; Evans, Austin M.; Worthington, Max J. H.; Albuquerque, Inês S.; Slattery, Ashley D.; Gibson, Christopher T.; Campbell, Jonathan A.; Lewis, David A.; Bernardes, Gonçalo J. L.
2015-01-01
Abstract A polysulfide material was synthesized by the direct reaction of sulfur and d‐limonene, by‐products of the petroleum and citrus industries, respectively. The resulting material was processed into functional coatings or molded into solid devices for the removal of palladium and mercury salts from water and soil. The binding of mercury(II) to the sulfur‐limonene polysulfide resulted in a color change. These properties motivate application in next‐generation environmental remediation and mercury sensing. PMID:26481099
Materials for Photovoltaic Applications
NASA Astrophysics Data System (ADS)
Dimova-Malinovska, Doriana
Energy priorities are changing nowadays. As mankind will probably have to face energy crisis, factors such as energy independence, energy security, stability of energy supply and the variety of energy sources become much more vital these days. Photovoltaics is exceptional compared to other renewable sources of energy due to its wide opportunity to gain energetic and environmental benefits. An overview of the present state of knowledge of the materials aspects of photovoltaic cells will be given, and new semiconductor materials, including nanomaterials, with potential for application in photovoltaic devices will be identified.
Recent Advancements in Functionalized Paper-Based Electronics.
Lin, Yang; Gritsenko, Dmitry; Liu, Qian; Lu, Xiaonan; Xu, Jie
2016-08-17
Building electronic devices on ubiquitous paper substrates has recently drawn extensive attention due to its light weight, low cost, environmental friendliness, and ease of fabrication. Recently, a myriad of advancements have been made to improve the performance of paper electronics for various applications, such as basic electronic components, energy storage devices, generators, antennas, and electronic circuits. This review aims to summarize this progress and discuss different perspectives of paper electronics as well as the remaining challenges yet to be overcome in this field. Other aspects included in this review are the fundamental characteristics of paper, modification of paper with functional materials, and various methods for device fabrication.
Degradability of Polymers for Implantable Biomedical Devices
Lyu, SuPing; Untereker, Darrel
2009-01-01
Many key components of implantable medical devices are made from polymeric materials. The functions of these materials include structural support, electrical insulation, protection of other materials from the environment of the body, and biocompatibility, as well as other things such as delivery of a therapeutic drug. In such roles, the stability and integrity of the polymer, over what can be a very long period of time, is very important. For most of these functions, stability over time is desired, but in other cases, the opposite–the degradation and disappearance of the polymer over time is required. In either case, it is important to understand both the chemistry that can lead to the degradation of polymers as well as the kinetics that controls these reactions. Hydrolysis and oxidation are the two classes of reactions that lead to the breaking down of polymers. Both are discussed in detail in the context of the environmental factors that impact the utility of various polymers for medical device applications. Understanding the chemistry and kinetics allows prediction of stability as well as explanations for observations such as porosity and the unexpected behavior of polymeric composite materials in some situations. In the last part, physical degradation such interfacial delamination in composites is discussed. PMID:19865531
Optical Analysis of Transparent Polymeric Material Exposed to Simulated Space Environment
NASA Technical Reports Server (NTRS)
Edwards, David L.; Finckenor, Miria M.
1999-01-01
Transparent polymeric materials are being designed and utilized as solar concentrating lenses for spacecraft power and propulsion systems. These polymeric lenses concentrate solar energy onto energy conversion devices such as solar cells and thermal energy systems. The conversion efficiency is directly related to the transmissivity of the polymeric lens. The Environmental Effects Group of the Marshall Space Flight Center's Materials, Processes, and Manufacturing Department exposed a variety of materials to a simulated space environment and evaluated them for an, change in optical transmission. These materials include Lexan(TM), polyethylene terephthalate (PET). several formulations of Tefzel(TM). and Teflon(TM), and silicone DC 93-500. Samples were exposed to a minimum of 1000 Equivalent Sun Hours (ESH) of near-UV radiation (250 - 400 nm wavelength). Data will be presented on materials exposed to charged particle radiation equivalent to a five-year dose in geosynchronous orbit. These exposures were performed in MSFC's Combined Environmental Effects Test Chamber, a unique facility with the capability to expose materials simultaneously or sequentially to protons, low-energy electrons, high-energy electrons, near UV radiation and vacuum UV radiation.Prolonged exposure to the space environment will decrease the polymer film's transmission and thus reduce the conversion efficiency. A method was developed to normalize the transmission loss and thus rank the materials according to their tolerance to space environmental exposure. Spectral results and the material ranking according to transmission loss are presented.
Examination system utilizing ionizing radiation and a flexible, miniature radiation detector probe
Majewski, S.; Kross, B.J.; Zorn, C.J.; Majewski, L.A.
1996-10-22
An optimized examination system and method based on the Reverse Geometry X-Ray{trademark} (RGX{trademark}) radiography technique are presented. The examination system comprises a radiation source, at least one flexible, miniature radiation detector probe positioned in appropriate proximity to the object to be examined and to the radiation source with the object located between the source and the probe, a photodetector device attachable to an end of the miniature radiation probe, and a control unit integrated with a display device connected to the photodetector device. The miniature radiation detector probe comprises a scintillation element, a flexible light guide having a first end optically coupled to the scintillation element and having a second end attachable to the photodetector device, and an opaque, environmentally-resistant sheath surrounding the flexible light guide. The probe may be portable and insertable, or may be fixed in place within the object to be examined. An enclosed, flexible, liquid light guide is also presented, which comprises a thin-walled flexible tube, a liquid, preferably mineral oil, contained within the tube, a scintillation element located at a first end of the tube, closures located at both ends of the tube, and an opaque, environmentally-resistant sheath surrounding the flexible tube. The examination system and method have applications in non-destructive material testing for voids, cracks, and corrosion, and may be used in areas containing hazardous materials. In addition, the system and method have applications for medical and dental imaging. 5 figs.
Examination system utilizing ionizing radiation and a flexible, miniature radiation detector probe
Majewski, Stanislaw; Kross, Brian J.; Zorn, Carl J.; Majewski, Lukasz A.
1996-01-01
An optimized examination system and method based on the Reverse Geometry X-Ray.RTM. (RGX.RTM.) radiography technique are presented. The examination system comprises a radiation source, at least one flexible, miniature radiation detector probe positioned in appropriate proximity to the object to be examined and to the radiation source with the object located between the source and the probe, a photodetector device attachable to an end of the miniature radiation probe, and a control unit integrated with a display device connected to the photodetector device. The miniature radiation detector probe comprises a scintillation element, a flexible light guide having a first end optically coupled to the scintillation element and having a second end attachable to the photodetector device, and an opaque, environmentally-resistant sheath surrounding the flexible light guide. The probe may be portable and insertable, or may be fixed in place within the object to be examined. An enclosed, flexible, liquid light guide is also presented, which comprises a thin-walled flexible tube, a liquid, preferably mineral oil, contained within the tube, a scintillation element located at a first end of the tube, closures located at both ends of the tube, and an opaque, environmentally-resistant sheath surrounding the flexible tube. The examination system and method have applications in non-destructive material testing for voids, cracks, and corrosion, and may be used in areas containing hazardous materials. In addition, the system and method have applications for medical and dental imaging.
Liu, Yun; Hao, Wei; Yao, Huiying; Li, Shuzhou; Wu, Yuchen; Zhu, Jia; Jiang, Lei
2018-01-01
Semiconducting polymers with π-conjugated electronic structures have potential application in the large-scale printable fabrication of high-performance electronic and optoelectronic devices. However, owing to their poor environmental stability and high-cost synthesis, polymer semiconductors possess limited device implementation. Here, an approach for constructing a π-conjugated polymer/graphene composite material to circumvent these limitations is provided, and then this material is patterned into 1D arrays. Driven by the π-π interaction, several-layer polymers can be adsorbed onto the graphene planes. The low consumption of the high-cost semiconductor polymers and the mass production of graphene contribute to the low-cost fabrication of the π-conjugated polymer/graphene composite materials. Based on the π-conjugated system, a reduced π-π stacking distance between graphene and the polymer can be achieved, yielding enhanced charge-transport properties. Owing to the incorporation of graphene, the composite material shows improved thermal stability. More generally, it is believed that the construction of the π-conjugated composite shows clear possibility of integrating organic molecules and 2D materials into microstructure arrays for property-by-design fabrication of functional devices with large area, low cost, and high efficiency. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Flexible Transparent Electronic Gas Sensors.
Wang, Ting; Guo, Yunlong; Wan, Pengbo; Zhang, Han; Chen, Xiaodong; Sun, Xiaoming
2016-07-01
Flexible and transparent electronic gas sensors capable of real-time, sensitive, and selective analysis at room-temperature, have gained immense popularity in recent years for their potential to be integrated into various smart wearable electronics and display devices. Here, recent advances in flexible transparent sensors constructed from semiconducting oxides, carbon materials, conducting polymers, and their nanocomposites are presented. The sensing material selection, sensor device construction, and sensing mechanism of flexible transparent sensors are discussed in detail. The critical challenges and future development associated with flexible and transparent electronic gas sensors are presented. Smart wearable gas sensors are believed to have great potential in environmental monitoring and noninvasive health monitoring based on disease biomarkers in exhaled gas. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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.
High-performance green flexible electronics based on biodegradable cellulose nanofibril paper
Yei Hwan Jung; Tzu-Hsuan Chang; Huilong Zhang; Chunhua Yao; Qifeng Zheng; Vina W. Yang; Hongyi Mi; Munho Kim; Sang June Cho; Dong-Wook Park; Hao Jiang; Juhwan Lee; Yijie Qiu; Weidong Zhou; Zhiyong Cai; Shaoqin Gong; Zhenqiang Ma
2015-01-01
Todayâs consumer electronics, such as cell phones, tablets and other portable electronic devices, are typically made of non-renewable, non-biodegradable, and sometimes potentially toxic (for example, gallium arsenide) materials. These consumer electronics are frequently upgraded or discarded, leading to serious environmental contamination. Thus, electronic systems...
Wang, Sibo; Ren, Zheng; Guo, Yanbing; ...
2016-03-21
We report the scalable three-dimensional (3-D) integration of functional nanostructures into applicable platforms represents a promising technology to meet the ever-increasing demands of fabricating high performance devices featuring cost-effectiveness, structural sophistication and multi-functional enabling. Such an integration process generally involves a diverse array of nanostructural entities (nano-entities) consisting of dissimilar nanoscale building blocks such as nanoparticles, nanowires, and nanofilms made of metals, ceramics, or polymers. Various synthetic strategies and integration methods have enabled the successful assembly of both structurally and functionally tailored nano-arrays into a unique class of monolithic devices. The performance of nano-array based monolithic devices is dictated bymore » a few important factors such as materials substrate selection, nanostructure composition and nano-architecture geometry. Therefore, the rational material selection and nano-entity manipulation during the nano-array integration process, aiming to exploit the advantageous characteristics of nanostructures and their ensembles, are critical steps towards bridging the design of nanostructure integrated monolithic devices with various practical applications. In this article, we highlight the latest research progress of the two-dimensional (2-D) and 3-D metal and metal oxide based nanostructural integrations into prototype devices applicable with ultrahigh efficiency, good robustness and improved functionality. Lastly, selective examples of nano-array integration, scalable nanomanufacturing and representative monolithic devices such as catalytic converters, sensors and batteries will be utilized as the connecting dots to display a roadmap from hierarchical nanostructural assembly to practical nanotechnology implications ranging from energy, environmental, to chemical and biotechnology areas.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wang, Sibo; Ren, Zheng; Guo, Yanbing
We report the scalable three-dimensional (3-D) integration of functional nanostructures into applicable platforms represents a promising technology to meet the ever-increasing demands of fabricating high performance devices featuring cost-effectiveness, structural sophistication and multi-functional enabling. Such an integration process generally involves a diverse array of nanostructural entities (nano-entities) consisting of dissimilar nanoscale building blocks such as nanoparticles, nanowires, and nanofilms made of metals, ceramics, or polymers. Various synthetic strategies and integration methods have enabled the successful assembly of both structurally and functionally tailored nano-arrays into a unique class of monolithic devices. The performance of nano-array based monolithic devices is dictated bymore » a few important factors such as materials substrate selection, nanostructure composition and nano-architecture geometry. Therefore, the rational material selection and nano-entity manipulation during the nano-array integration process, aiming to exploit the advantageous characteristics of nanostructures and their ensembles, are critical steps towards bridging the design of nanostructure integrated monolithic devices with various practical applications. In this article, we highlight the latest research progress of the two-dimensional (2-D) and 3-D metal and metal oxide based nanostructural integrations into prototype devices applicable with ultrahigh efficiency, good robustness and improved functionality. Lastly, selective examples of nano-array integration, scalable nanomanufacturing and representative monolithic devices such as catalytic converters, sensors and batteries will be utilized as the connecting dots to display a roadmap from hierarchical nanostructural assembly to practical nanotechnology implications ranging from energy, environmental, to chemical and biotechnology areas.« less
NASA Astrophysics Data System (ADS)
Muqeet Rehman, Muhammad; Uddin Siddiqui, Ghayas; Kim, Sowon; Choi, Kyung Hyun
2017-08-01
Pursuit of the most appropriate materials and fabrication methods is essential for developing a reliable, rewritable and flexible memory device. In this study, we have proposed an advanced 2D nanocomposite of white graphene (hBN) flakes embedded with graphene quantum dots (GQDs) as the functional layer of a flexible memory device owing to their unique electrical, chemical and mechanical properties. Unlike the typical sandwich type structure of a memory device, we developed a cost effective planar structure, to simplify device fabrication and prevent sneak current. The entire device fabrication was carried out using printing technology followed by encapsulation in an atomically thin layer of aluminum oxide (Al2O3) for protection against environmental humidity. The proposed memory device exhibited attractive bipolar switching characteristics of high switching ratio, large electrical endurance and enhanced lifetime, without any crosstalk between adjacent memory cells. The as-fabricated device showed excellent durability for several bending cycles at various bending diameters without any degradation in bistable resistive states. The memory mechanism was deduced to be conductive filamentary; this was validated by illustrating the temperature dependence of bistable resistive states. Our obtained results pave the way for the execution of promising 2D material based next generation flexible and non-volatile memory (NVM) applications.
Stark, Peter C [Los Alamos, NM; Zurek, Eduardo [Barranquilla, CO; Wheat, Jeffrey V [Fort Walton Beach, FL; Dunbar, John M [Santa Fe, NM; Olivares, Jose A [Los Alamos, NM; Garcia-Rubio, Luis H [Temple Terrace, FL; Ward, Michael D [Los Alamos, NM
2011-07-26
There is provided a method and device for remote sampling, preparation and optical interrogation of a sample using light scattering and light absorption methods. The portable device is a filtration-based device that removes interfering background particle material from the sample matrix by segregating or filtering the chosen analyte from the sample solution or matrix while allowing the interfering background particles to be pumped out of the device. The segregated analyte is then suspended in a diluent for analysis. The device is capable of calculating an initial concentration of the analyte, as well as diluting the analyte such that reliable optical measurements can be made. Suitable analytes include cells, microorganisms, bioparticles, pathogens and diseases. Sample matrixes include biological fluids such as blood and urine, as well as environmental samples including waste water.
Paper-polymer composite devices with minimal fluorescence background.
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.
Electronic waste (e-waste): material flows and management practices in Nigeria.
Nnorom, Innocent Chidi; Osibanjo, Oladele
2008-01-01
The growth in electrical and electronic equipment (EEE) production and consumption has been exponential in the last two decades. This has been as a result of the rapid changes in equipment features and capabilities, decrease in prices, and the growth in internet use. This creates a large volume of waste stream of obsolete electrical and electronic devices (e-waste) in developed countries. There is high level of trans-boundary movement of these devices as secondhand electronic equipment into developing countries in an attempt to bridge the 'digital divide'. The past decade has witnessed a phenomenal advancement in information and communication technology (ICT) in Nigeria, most of which rely on imported secondhand devices. This paper attempts to review the material flow of secondhand/scrap electronic devices into Nigeria, the current management practices for e-waste and the environmental and health implications of such low-end management practices. Establishment of formal recycling facilities, introduction of legislation dealing specifically with e-waste and the confirmation of the functionality of secondhand EEE prior to importation are some of the options available to the government in dealing with this difficult issue.
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.
Prospects of Nanotechnology in Clinical Immunodiagnostics
Ansari, Anees A.; Alhoshan, Mansour; Alsalhi, Mohamad S.; Aldwayyan, Abdullah S.
2010-01-01
Nanostructured materials are promising compounds that offer new opportunities as sensing platforms for the detection of biomolecules. Having micrometer-scale length and nanometer-scale diameters, nanomaterials can be manipulated with current nanofabrication methods, as well as self-assembly techniques, to fabricate nanoscale bio-sensing devices. Nanostructured materials possess extraordinary physical, mechanical, electrical, thermal and multifunctional properties. Such unique properties advocate their use as biomimetic membranes to immobilize and modify biomolecules on the surface of nanoparticles. Alignment, uniform dispersion, selective growth and diameter control are general parameters which play critical roles in the successful integration of nanostructures for the fabrication of bioelectronic sensing devices. In this review, we focus on different types and aspects of nanomaterials, including their synthesis, properties, conjugation with biomolecules and their application in the construction of immunosensing devices. Some key results from each cited article are summarized by relating the concept and mechanism behind each sensor, experimental conditions and the behavior of the sensor under different conditions, etc. The variety of nanomaterial-based bioelectronic devices exhibiting novel functions proves the unique properties of nanomaterials in such sensing devices, which will surely continue to expand in the future. Such nanomaterial based devices are expected to have a major impact in clinical immunodiagnostics, environmental monitoring, security surveillance and for ensuring food safety. PMID:22163566
Ionic electroactive polymer artificial muscles in space applications.
Punning, Andres; Kim, Kwang J; Palmre, Viljar; Vidal, Frédéric; Plesse, Cédric; Festin, Nicolas; Maziz, Ali; Asaka, Kinji; Sugino, Takushi; Alici, Gursel; Spinks, Geoff; Wallace, Gordon; Must, Indrek; Põldsalu, Inga; Vunder, Veiko; Temmer, Rauno; Kruusamäe, Karl; Torop, Janno; Kaasik, Friedrich; Rinne, Pille; Johanson, Urmas; Peikolainen, Anna-Liisa; Tamm, Tarmo; Aabloo, Alvo
2014-11-05
A large-scale effort was carried out to test the performance of seven types of ionic electroactive polymer (IEAP) actuators in space-hazardous environmental factors in laboratory conditions. The results substantiate that the IEAP materials are tolerant to long-term freezing and vacuum environments as well as ionizing Gamma-, X-ray, and UV radiation at the levels corresponding to low Earth orbit (LEO) conditions. The main aim of this material behaviour investigation is to understand and predict device service time for prolonged exposure to space environment.
Improving the Performance of Semiconductor Sensor Devices Using Surface Functionalization
NASA Astrophysics Data System (ADS)
Rohrbaugh, Nathaniel W.
As production and understanding of III-nitride growth has progressed, this class of material has been used for its semiconducting properties in the fields of computer processing, microelectronics, and LEDs. As understanding of materials properties has advanced, devices were fabricated to be sensitive to environmental surroundings such as pH, gas, or ionic concentration. Simultaneously the world of pharmaceuticals and environmental science has come to the age where the use of wearable devices and active environmental sensing can not only help us learn more about our surroundings, but help save lives. At the crossroads of these two fields work has been done in marrying the high stability and electrical properties of the III-nitrides with the needs of a growing sensor field for various environments and stimuli. Device architecture can only get one so far, and thus the need for well understood surface functionalization techniques has arisen in the field of III-nitride environmental sensing. Many existing schemes for functionalization involve chemistries that may be unfriendly to a biological environment, unstable in solution, or expensive to produce. One possible solution to these issues is the work presented here, which highlights a surface modification scheme utilizing phosphonic acid based chemistry and biomolecular attachment. This dissertation presents a set of studies and experiments quantifying and analyzing the response behaviors of AlGaN/GaN field effect transistor (FET) devices via their interfacial electronic properties. Additional investigation was done on the modification of these surfaces, effects of stressful environmental conditions, and the utility of the phosphonic acid surface treatments. Signals of AlGaN/GaN FETs were measured as IDrain values and in the earliest study an average signal increase of 96.43% was observed when surfaces were incubated in a solution of a known recognition peptide sequence (SVSVGMKPSPRP). This work showed that even without a form of surface modification the devices were capable of generating a response in the presence of a charged biomolecule. Solution exposure tests done devices showed that incubating peptides on the device surfaces produced a weak interaction and following 24 hrs of soaking no signs of peptide remained via XPS analysis. Subsequent testing was done to incorporate the phosphonic acid functionalization techniques shown previously by other members of this lab to the AlGaN/GaN surfaces as a remedy to this solution instability. In this second study FETs were modified using a heated phosphoric acid:ethephon etch followed by an incubation in TAT-C peptide. Resulting IV measurements done on the samples showed a shift in threshold voltage of the FETs following the etching procedure followed by a recovery of this shift from prolonged solution exposure. In total samples were given 168 hours of soaking and showed persistent peptide presence through the N 1s peak from XPS scans. FETs modified with this phosphonic acid derivative were examined in a third study under a simulated pollutant sensing scenario by measuring varied concentrations of Hg via a phytochelatin peptide bound to FET surfaces. HNO3 used in the Hg stock solution led to degradation of the FET signal but did not remove the phytochelatin layer. This led to a compensation effect in sensing the highest levels of Hg, lower concentrations however were successfully tested and showed varied responses from the FETs relative to the Hg content. In a concluding study on devices work was done to understand broader effects on the AlGaN/GaN FETs relative to a simulated biological sensing environment. Here an effect was noted from the addition of a biological fouling solution to the FETs and an increase in this effect when the biofouling was done to a phosphonic modified FET surface. Additionally devices were modified and soaked for 5 weeks and showed no shift or degradation in signal. Lastly in controlling for gate width of the FET it was found that the shorter 50 im gates were more susceptible to environmental interference than the 100 and 150 im gated devices. Thus this work has shown that modifying AlGaN/GaN devices with phosphonic acid derivatives is a viable functionalization method that is both adaptable and stable in solution over time. In moving forward, opportunities are available for testing a larger variety of analytes in both the medical and environmental fields. The final goal for this technology would be the fabrication and design of a multi-device sensing unit leading to eventual production of these sensors on an industrial scale for the use in future personal medical devices or environmental monitoring systems.
Life cycle assessment of Mexican polymer and high-durability cotton paper banknotes.
Luján-Ornelas, Cristina; Mancebo Del C Sternenfels, Uriel; Güereca, Leonor Patricia
2018-07-15
This study compares the environmental performance of Mexican banknotes printed on high-durability cotton paper (HD paper) and thermoplastic polymer (polymer) through a life cycle assessment to appraise the environmental impacts from the extraction of raw materials to the final disposal of the banknotes. The functional unit was defined considering the next parameters: 1) lifespan of the banknotes, stablished in 31.5 and 54months for HD paper and polymer, respectively; 2) denomination, selecting $200 pesos banknotes; 3) a 5year time frame and 4) a defined amount of money, in this case stablished as the monthly cash supply of an average Mexican household, equaling $12,708 pesos. Accordingly, 121 pieces for the HD paper and 71 pieces for the polymer banknotes were analyzed. The results favor the banknotes printed on polymer substrate primarily because of the longer lifespan of this type of material; however, there is a considerable environmental impact in the stages of distribution, followed by the extraction of the raw materials (crude oil) during manufacturing. Regarding the HD cotton paper, the major impact corresponds to extraction of the raw materials, followed by the distribution of the banknotes. The inclusion of the automatic teller machines (ATMs) in the life cycle assessment of banknotes shows that the electricity required by these devices became the largest contributor to the environmental impacts. Additionally, the sensitivity analysis that the average lifetime of the banknotes is a determining factor for the environmental impacts associated with the whole life cycle of this product. The life cycle stages that refer to the extraction of the raw materials, combined with the average lifetime of the banknotes and the electricity required during the usage stage, are determining factors in the total environmental impact associated with Mexican banknotes. Copyright © 2018 Elsevier B.V. All rights reserved.
ERIC Educational Resources Information Center
Smith, Merry K.; Martin-Peralta, Daphnie G.; Pivak, Polina A.; Mirica, Katherine A.
2017-01-01
Carbon nanomaterials have promising utility in chemical sensing including applications in preserving occupational safety, monitoring of environmental pollution, and human health. While recent advances in device fabrication and molecular design of functional materials have enabled rapid fabrication of chemical sensors from carbon nanomaterials,…
Quantifying Risk for Decentralized Offensive Cyber Operations
2017-06-01
information. Additionally, radio communications equipment were reevaluated in order to provide longer ranges, last longer on battery power, and be...every other device monitoring that radio frequency . Additionally, wireless signals are limited by distance, the construction materials in walls... communications , socio-psychological, and personality factors in the maintenance of crew coordination. Aviation, Space, and Environmental Medicine, 53( 11
Miniature personal UV solar dosimeter
NASA Technical Reports Server (NTRS)
Adams, R. R.; Macconochie, I. O.; Poole, B. D., Jr.
1981-01-01
Small light-powered meter measures accumulated radiation in ultraviolet or other selected regions. Practical advantages are device's low cost, small size, accuracy, and adaptability to specific wave-band measurements. Medical applications include detection of skin cancer, vitamin D production, and jaundice. Dosimeter also measures sunlight for solar energy designs, agriculture and meteorology, and monitors stability of materials and environmental and occupational lighting.
Ceramic Integration Technologies for Energy and Aerospace Applications
NASA Technical Reports Server (NTRS)
Singh, Mrityunjay; Asthana, Ralph N.
2007-01-01
Robust and affordable integration technologies for advanced ceramics are required to improve the performance, reliability, efficiency, and durability of components, devices, and systems based on them in a wide variety of energy, aerospace, and environmental applications. Many thermochemical and thermomechanical factors including joint design, analysis, and optimization must be considered in integration of similar and dissimilar material systems.
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.
All-inkjet-printed flexible ZnO micro photodetector for a wearable UV monitoring device.
Tran, Van-Thai; Wei, Yuefan; Yang, Hongyi; Zhan, Zhaoyao; Du, Hejun
2017-03-03
Fabrication of small-sized patterns of inorganic semiconductor onto flexible substrates is a major concern when manufacturing wearable devices for measuring either biometric or environmental parameters. In this study, micro-sized flexible ZnO UV photodetectors have been thoroughly prepared by a facile inkjet printing technology and followed with heat treatments. A simple ink recipe of zinc acetate precursor solution was investigated. It is found that the substrate temperature during zinc precursor ink depositing has significant effects on ZnO pattern shape, film morphology, and crystallization. The device fabricated from the additive manufacturing approach has good bendability, Ohmic contact, short response time as low as 0.3 s, and high on/off ratio of 3525. We observed the sensor's dependence of response/decay time by the illuminating UV light intensity. The whole process is based on additive manufacturing which has many benefits such as rapid prototyping, saving material, being environmentally friendly, and being capable of creating high-resolution patterns. In addition, this method can be applied to flexible substrates, which makes the device more applicable for applications requiring flexibility such as wearable devices. The proposed all-inkjet-printing approach for a micro-sized ZnO UV photodetector would significantly simplify the fabrication process of micro-sized inorganic semiconductor-based devices. A potential application is real-time monitoring of UV light exposure to warn users about unsafe direct sunlight to implement suitable avoidance solutions.
Low-cost, solution processable carbon nanotube supercapacitors and their characterization
NASA Astrophysics Data System (ADS)
Lehtimäki, Suvi; Tuukkanen, Sampo; Pörhönen, Juho; Moilanen, Pasi; Virtanen, Jorma; Honkanen, Mari; Lupo, Donald
2014-06-01
We report ecological and low-cost carbon nanotube (CNT) supercapacitors fabricated using a simple, scalable solution processing method, where the use of a highly porous and electrically conductive active material eliminates the need for a current collector. Electrodes were fabricated on a poly(ethylene terephthalate) substrate from a printable multi-wall CNT ink, where the CNTs are solubilized in water using xylan as a dispersion agent. The dispersion method facilitates a very high concentration of CNTs in the ink. Supercapacitors were assembled using a paper separator and an aqueous NaCl electrolyte and the devices were characterized with a galvanostatic discharge method defined by an industrial standard. The capacitance of the 2 cm^2 devices was 6 mF/cm^2 (2.3 F/g) and equivalent series resistance 80 Ω . Low-cost supercapacitors fabricated from safe and environmentally friendly materials have potential applications as energy storage devices in ubiquitous and autonomous intelligence as well as in disposable low-end products.
Hydrogel nanoparticle based immunoassay
Liotta, Lance A; Luchini, Alessandra; Petricoin, Emanuel F; Espina, Virginia
2015-04-21
An immunoassay device incorporating porous polymeric capture nanoparticles within either the sample collection vessel or pre-impregnated into a porous substratum within fluid flow path of the analytical device is presented. This incorporation of capture particles within the immunoassay device improves sensitivity while removing the requirement for pre-processing of samples prior to loading the immunoassay device. A preferred embodiment is coreshell bait containing capture nanoparticles which perform three functions in one step, in solution: a) molecular size sieving, b) target analyte sequestration and concentration, and c) protection from degradation. The polymeric matrix of the capture particles may be made of co-polymeric materials having a structural monomer and an affinity monomer, the affinity monomer having properties that attract the analyte to the capture particle. This device is useful for point of care diagnostic assays for biomedical applications and as field deployable assays for environmental, pathogen and chemical or biological threat identification.
Novel Photovoltaic Devices Using Ferroelectric Material and Colloidal Quantum Dots
NASA Astrophysics Data System (ADS)
Paik, Young Hun
As the global concern for the financial and environmental costs of traditional energy resources increases, research on renewable energy, most notably solar energy, has taken center stage. Many alternative photovoltaic (PV) technologies for 'the next generation solar cell' have been extensively studied to overcome the Shockley-Queisser 31% efficiency limit as well as tackle the efficiency vs. cost issues. This dissertation focuses on the novel photovoltaic mechanism for the next generation solar cells using two inorganic nanomaterials, nanocrystal quantum dots and ferroelectric nanoparticles. Lead zirconate titanate (PZT) materials are widely studied and easy to synthesize using solution based chemistry. One of the fascinating properties of the PZT material is a Bulk Photovoltaic effect (BPVE). This property has been spotlighted because it can produce very high open circuit voltage regardless of the electrical bandgap of the materials. However, the poor optical absorption of the PZT materials and the required high temperature to form the ferroelectric crystalline structure have been obstacles to fabricate efficient photovoltaic devices. Colloidal quantum dots also have fascinating optical and electrical properties such as tailored absorption spectrum, capability of the bandgap engineering due to the wide range of material selection and quantum confinement, and very efficient carrier dynamics called multiple exciton generations. In order to utilize these properties, many researchers have put numerous efforts in colloidal quantum dot photovoltaic research and there has been remarkable progress in the past decade. However, several drawbacks are still remaining to achieve highly efficient photovoltaic device. Traps created on the large surface area, low carrier mobility, and lower open circuit voltage while increasing the absorption of the solar spectrum is main issues of the nanocrystal based photovoltaic effect. To address these issues and to take the advantages of the two materials, this dissertation focused on material synthesis for low cost solution process for both materials, fabrication of various device structures and electrical/optical characterization to understand the underlying physics. We successfully demonstrated lead sulfide quantum dots (PbS QDs) and lead zirconate titanate nanoparticles (PZT NPs) in an aqueous solution and fabricated a photosensitive device. Solution based low-temperature process was used to fabricate a PbS QD and a PZT NP device. We exhibited a superior photoresponse and ferroelectric photovoltaic properties with the novel PZT NP device and studied the physics on domain wall effect and internal polarity effect. PZT NP was mainly investigated because PZT NP device is the first report as a photosensitive device with a successful property demonstration, as we know of. PZT's crystalline structure and the size of the nanocrystals were studied using X-ray diffraction and TEM (Transmission electron microscopy) respectively. We observed < 100 nm of PZT NPs and this result matched with DLS (dynamic light scattering) measurement. We fabricated ferroelectric devices using the PZT NPs for the various optical and electrical characterizations and verified ferroelectric properties including ferroelectric hysteresis loop. We also observed a typical ferroelectric photovoltaic effect from a PZT NP based device which was fabricated on an ITO substrate. We synthesized colloidal quantum dots (CQD) with the inexpensive soluble process. Fabricated PbS QD was used for the hybrid device with PZT thin films. J-V measured and the result shows superior open circuit voltage characteristics compared to conventional PbS QD PV devices, and resulting the improvement of the solar cell efficiency. This Ferroelectrics and Quantum Dots (FE-QDs) device also the first trial and the success as we know of.
Abatement of waste gases and water during the processes of semiconductor fabrication.
Wen, Rui-mei; Liang, Jun-wu
2002-10-01
The purpose of this article is to examine the methods and equipment for abating waste gases and water produced during the manufacture of semiconductor materials and devices. Three separating methods and equipment are used to control three different groups of electronic wastes. The first group includes arsine and phosphine emitted during the processes of semiconductor materials manufacture. The abatement procedure for this group of pollutants consists of adding iodates, cupric and manganese salts to a multiple shower tower (MST) structure. The second group includes pollutants containing arsenic, phosphorus, HF, HCl, NO2, and SO3 emitted during the manufacture of semiconductor materials and devices. The abatement procedure involves mixing oxidants and bases in an oval column with a separator in the middle. The third group consists of the ions of As, P and heavy metals contained in the waste water. The abatement procedure includes adding CaCO3 and ferric salts in a flocculation-sedimentation compact device equipment. Test results showed that all waste gases and water after the abatement procedures presented in this article passed the discharge standards set by the State Environmental Protection Administration of China.
Space Environmental Effects on the Optical Properties of Selected Transparent Polymers
NASA Technical Reports Server (NTRS)
Edwards, David L.; Willowby, Douglas J.; Hubbs, Whitney C.; Piszczor, Michael F., Jr.; Bowden, Mary L.
1997-01-01
Transparent polymer films are currently considered for use as solar concentrating lenses for spacecraft power and propulsion systems. These polymer films concentrate solar energy onto energy conversion devices such as solar cells and thermal energy systems. Conversion efficiency is directly related to the polymer transmission. Space environmental effects will decrease the transmission and thus reduce the conversion efficiency. This investigation focuses on the effects of ultraviolet and charged particle radiation on the transmission of selected transparent polymers. Multiple candidate polymer samples were exposed to near ultraviolet (NUV) radiation to screen the materials and select optimum materials for further study. All materials experienced transmission degradation of varying degree. A method was developed to normalize the transmission loss and thus rank the materials according to their tolerance of NUV. Teflon(Tm) FEP and Teflon(Tm) PFA were selected for further study. These materials were subjected to a combined charged particle dose equivalent to 5 years in a typical geosynchronous Earth orbit (GEO). Results from these NUV screening tests and the 5 year GEO equivalent dose are presented.
Functional Scanning Probe Imaging of Nanostructured Solar Energy Materials.
Giridharagopal, Rajiv; Cox, Phillip A; Ginger, David S
2016-09-20
From hybrid perovskites to semiconducting polymer/fullerene blends for organic photovoltaics, many new materials being explored for energy harvesting and storage exhibit performance characteristics that depend sensitively on their nanoscale morphology. At the same time, rapid advances in the capability and accessibility of scanning probe microscopy methods over the past decade have made it possible to study processing/structure/function relationships ranging from photocurrent collection to photocarrier lifetimes with resolutions on the scale of tens of nanometers or better. Importantly, such scanning probe methods offer the potential to combine measurements of local structure with local function, and they can be implemented to study materials in situ or devices in operando to better understand how materials evolve in time in response to an external stimulus or environmental perturbation. This Account highlights recent advances in the development and application of scanning probe microscopy methods that can help address such questions while filling key gaps between the capabilities of conventional electron microscopy and newer super-resolution optical methods. Focusing on semiconductor materials for solar energy applications, we highlight a range of electrical and optoelectronic scanning probe microscopy methods that exploit the local dynamics of an atomic force microscope tip to probe key properties of the solar cell material or device structure. We discuss how it is possible to extract relevant device properties using noncontact scanning probe methods as well as how these properties guide materials development. Specifically, we discuss intensity-modulated scanning Kelvin probe microscopy (IM-SKPM), time-resolved electrostatic force microscopy (trEFM), frequency-modulated electrostatic force microscopy (FM-EFM), and cantilever ringdown imaging. We explain these developments in the context of classic atomic force microscopy (AFM) methods that exploit the physics of cantilever motion and photocarrier generation to provide robust, nanoscale measurements of materials physics that are correlated with device operation. We predict that the multidimensional data sets made possible by these types of methods will become increasingly important as advances in data science expand capabilities and opportunities for image correlation and discovery.
Organic electronics with polymer dielectrics on plastic substrates fabricated via transfer printing
NASA Astrophysics Data System (ADS)
Hines, Daniel R.
Printing methods are fast becoming important processing techniques for the fabrication of flexible electronics. Some goals for flexible electronics are to produce cheap, lightweight, disposable radio frequency identification (RFID) tags, very large flexible displays that can be produced in a roll-to-roll process and wearable electronics for both the clothing and medical industries. Such applications will require fabrication processes for the assembly of dissimilar materials onto a common substrate in ways that are compatible with organic and polymeric materials as well as traditional solid-state electronic materials. A transfer printing method has been developed with these goals and application in mind. This printing method relies primarily on differential adhesion where no chemical processing is performed on the device substrate. It is compatible with a wide variety of materials with each component printed in exactly the same way, thus avoiding any mixed processing steps on the device substrate. The adhesion requirements of one material printed onto a second are studied by measuring the surface energy of both materials and by surface treatments such as plasma exposure or the application of self-assembled monolayers (SAM). Transfer printing has been developed within the context of fabricating organic electronics onto plastic substrates because these materials introduce unique opportunities associated with processing conditions not typically required for traditional semiconducting materials. Compared to silicon, organic semiconductors are soft materials that require low temperature processing and are extremely sensitive to chemical processing and environmental contamination. The transfer printing process has been developed for the important and commonly used organic semiconducting materials, pentacene (Pn) and poly(3-hexylthiophene) (P3HT). A three-step printing process has been developed by which these materials are printed onto an electrode subassembly consisting of previously printed electrodes separated by a polymer dielectric layer all on a plastic substrate. These bottom contact, flexible organic thin-film transistors (OTFT) have been compared to unprinted (reference) devices consisting of top contact electrodes and a silicon dioxide dielectric layer on a silicon substrate. Printed Pn and P3HT TFTs have been shown to out-perform the reference devices. This enhancement has been attributed to an annealing under pressure of the organic semiconducting material.
NASA Technical Reports Server (NTRS)
Wise, Stephanie A.; Buckley, John D.; Randolf, Henry W.; Verbelyi, Darren; Haertling, Gene H.; Hooker, Matthew W.; Selim, Raouf; Caton, Randall
1992-01-01
Thick films of superconductive material on low thermal conductivity substrates (e.g., yttria-stabilized zirconia and fused silica) are considered as a replacement for the existing electrical connections between the detector array and data acquisition and storage electronics in the cryogenic detector systems being developed by NASA. The paper describes some of the design constraints on the superconducting device and presents results of a preliminary analysis of the effects of vibration, gamma irradiation, and long-term exposure to high vacuum and liquid nitrogen encountered in operating such a device in space.
NASA Astrophysics Data System (ADS)
Wu, Guodong; Feng, Ping; Wan, Xiang; Zhu, Liqiang; Shi, Yi; Wan, Qing
2016-03-01
Recent progress in using biomaterials to fabricate functional electronics has got growing attention for the new generation of environmentally friendly and biocompatible electronic devices. As a kind of biological material with rich source, proteins are essential natural component of all organisms. At the same time, artificial synaptic devices are of great significance for neuromorphic systems because they can emulate the signal process and memory behaviors of biological synapses. In this report, natural chicken albumen with high proton conductivity was used as the coupling electrolyte film for organic/inorganic hybrid synaptic devices fabrication. Some important synaptic functions including paired-pulse facilitation, dynamic filtering, short-term to long-term memory transition and spatial summation and shunting inhibition were successfully mimicked. Our results are very interesting for biological friendly artificial neuron networks and neuromorphic systems.
Germanium detector passivated with hydrogenated amorphous germanium
Hansen, William L.; Haller, Eugene E.
1986-01-01
Passivation of predominantly crystalline semiconductor devices (12) is provided for by a surface coating (21) of sputtered hydrogenated amorphous semiconductor material. Passivation of a radiation detector germanium diode, for example, is realized by sputtering a coating (21) of amorphous germanium onto the etched and quenched diode surface (11) in a low pressure atmosphere of hydrogen and argon. Unlike prior germanium diode semiconductor devices (12), which must be maintained in vacuum at cryogenic temperatures to avoid deterioration, a diode processed in the described manner may be stored in air at room temperature or otherwise exposed to a variety of environmental conditions. The coating (21) compensates for pre-existing undesirable surface states as well as protecting the semiconductor device (12) against future impregnation with impurities.
Semiconductor with protective surface coating and method of manufacture thereof. [Patent application
Hansen, W.L.; Haller, E.E.
1980-09-19
Passivation of predominantly crystalline semiconductor devices is provided for by a surface coating of sputtered hydrogenated amorphous semiconductor material. Passivation of a radiation detector germanium diode, for example, is realized by sputtering a coating of amorphous germanium onto the etched and quenched diode surface in a low pressure atmosphere of hydrogen and argon. Unlike prior germanium diode semiconductor devices, which must be maintained in vacuum at cryogenic temperatures to avoid deterioration, a diode processed in the described manner may be stored in air at room temperature or otherwise exposed to a variety of environmental conditions. The coating compensates for pre-existing undesirable surface states as well as protecting the semiconductor device against future impregnation with impurities.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Liguori, R.; Aprano, S.; Rubino, A.
In this study we analyzed one of the environmental factors that could affect organic materials. Pentacene thin film samples were fabricated and the degradation of their electrical characteristics was measured when the devices were exposed to ultraviolet light irradiation. The results have been reported in terms of a trap density model, which provides a description of the dynamics of light induced electrically active defects in an organic semiconductor.
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.
NASA Astrophysics Data System (ADS)
Woo, Ju Yeon; Lee, Jongsoo; Han, Chang-Soo
2013-12-01
The long-term stability of quantum dot (QD)-based devices under harsh environmental conditions has been a critical bottleneck to be resolved for commercial use. Here, we demonstrate an extremely stable QD/alumina/polymer hybrid structure by combining internal atomic layer deposition (ALD) infilling with polymer encapsulation. ALD infilling and polymer encapsulation of QDs synergistically prohibit the degradation of QDs in terms of optical, thermal and humid attacks. Our hybrid QD/alumina/polymer film structure showed no noticeable reduction in photoluminescence even in a commercial grade test (85% humidity at 85 ° C) over 28 days. In addition, we successfully fabricated a QD-based light-emitting device with excellent long-term stability by incorporating hybrid QD/alumina/polymer film as a color conversion material on light-emitting diode chips.
Metal-Halide Perovskite Transistors for Printed Electronics: Challenges and Opportunities.
Lin, Yen-Hung; Pattanasattayavong, Pichaya; Anthopoulos, Thomas D
2017-12-01
Following the unprecedented rise in photovoltaic power conversion efficiencies during the past five years, metal-halide perovskites (MHPs) have emerged as a new and highly promising class of solar-energy materials. Their extraordinary electrical and optical properties combined with the abundance of the raw materials, the simplicity of synthetic routes, and processing versatility make MHPs ideal for cost-efficient, large-volume manufacturing of a plethora of optoelectronic devices that span far beyond photovoltaics. Herein looks beyond current applications in the field of energy, to the area of large-area electronics using MHPs as the semiconductor material. A comprehensive overview of the relevant fundamental material properties of MHPs, including crystal structure, electronic states, and charge transport, is provided first. Thereafter, recent demonstrations of MHP-based thin-film transistors and their application in logic circuits, as well as bi-functional devices such as light-sensing and light-emitting transistors, are discussed. Finally, the challenges and opportunities in the area of MHPs-based electronics, with particular emphasis on manufacturing, stability, and health and environmental concerns, are highlighted. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Noble metals: a toxicological appraisal of potential new environmental contaminants.
Brubaker, P E; Moran, J P; Bridbord, K; Hueter, F G
1975-01-01
The public health benefits expected by reducing known hazardous emissions from mobile sources should not be compromised by increasing levels of other potentially hazardous unregulated emissions. Catalytic converters are going to be used to meet the statutory requirements on carbon monoxide and hydrocarbon emissions from light duty motor vehicles. Platinum and palladium metals are the catalytic materials to be used in these emission control devices. Preliminary experimental evidence and analysis of the impact of these control devices on the future use and demand for platinum indicates that this metal may appear at detectable levels in the environment by the end of this decade. At the present time, platinum and palladium are not present in the public environment and represent potentially new environmental contaminants as a consequence of use of this new abatement control technology. There is relatively little information available to adequately assess the potential health hazards that may be associated with exposure to these metals and their compounds. Analysis of the environmental problems and concerns associated with possible new environmental contaminants are discussed. Limited estimates are made on community exposure by use of a meteorological dispersion model. Biodegradation potential and attention is also given to the limited toxicological information available. PMID:50939
NASA Technical Reports Server (NTRS)
Park, Brian V. (Inventor); Smith, Jr., Malcolm C. (Inventor); McGrath, Ralph D. (Inventor); Gilley, Michael D. (Inventor); Criscuolo, Lance (Inventor); Nelson, John L. (Inventor)
1996-01-01
A refrigerator is provided which combines the benefits of superinsulation materials with thermoelectric devices and phase change materials to provide an environmentally benign system that is energy efficient and can maintain relatively uniform temperatures for extended periods of time with relatively low electrical power requirements. The refrigerator includes a thermoelectric assembly having a thermoelectric device with a hot sink and a cold sink. The superinsulation materials include a plurality of vacuum panels. The refrigerator is formed from an enclosed structure having a door. The vacuum panels may be contained within the walls of the enclosed structure and the door. By mounting the thermoelectric assembly on the door, the manufacturer of the enclosed structure is simplified and the overall R rating of the refrigerator increased. Also an electrical motor and propellers may be mounted on the door to assist in the circulation of air to improve the efficiency of the cold sink and the hot sink. A propeller and/or impeller is preferably mounted within the refrigerator to assist in establishing the desired air circulation flow path.
Ionic electroactive polymer artificial muscles in space applications
Punning, Andres; Kim, Kwang J.; Palmre, Viljar; Vidal, Frédéric; Plesse, Cédric; Festin, Nicolas; Maziz, Ali; Asaka, Kinji; Sugino, Takushi; Alici, Gursel; Spinks, Geoff; Wallace, Gordon; Must, Indrek; Põldsalu, Inga; Vunder, Veiko; Temmer, Rauno; Kruusamäe, Karl; Torop, Janno; Kaasik, Friedrich; Rinne, Pille; Johanson, Urmas; Peikolainen, Anna-Liisa; Tamm, Tarmo; Aabloo, Alvo
2014-01-01
A large-scale effort was carried out to test the performance of seven types of ionic electroactive polymer (IEAP) actuators in space-hazardous environmental factors in laboratory conditions. The results substantiate that the IEAP materials are tolerant to long-term freezing and vacuum environments as well as ionizing Gamma-, X-ray, and UV radiation at the levels corresponding to low Earth orbit (LEO) conditions. The main aim of this material behaviour investigation is to understand and predict device service time for prolonged exposure to space environment. PMID:25372857
Electronic waste (e-waste): Material flows and management practices in Nigeria
DOE Office of Scientific and Technical Information (OSTI.GOV)
Nnorom, Innocent Chidi; Osibanjo, Oladele
The growth in electrical and electronic equipment (EEE) production and consumption has been exponential in the last two decades. This has been as a result of the rapid changes in equipment features and capabilities, decrease in prices, and the growth in internet use. This creates a large volume of waste stream of obsolete electrical and electronic devices (e-waste) in developed countries. There is high level of trans-boundary movement of these devices as secondhand electronic equipment into developing countries in an attempt to bridge the 'digital divide'. The past decade has witnessed a phenomenal advancement in information and communication technology (ICT)more » in Nigeria, most of which rely on imported secondhand devices. This paper attempts to review the material flow of secondhand/scrap electronic devices into Nigeria, the current management practices for e-waste and the environmental and health implications of such low-end management practices. Establishment of formal recycling facilities, introduction of legislation dealing specifically with e-waste and the confirmation of the functionality of secondhand EEE prior to importation are some of the options available to the government in dealing with this difficult issue.« less
An overview of carbon materials for flexible electrochemical capacitors.
He, Yongmin; Chen, Wanjun; Gao, Caitian; Zhou, Jinyuan; Li, Xiaodong; Xie, Erqing
2013-10-07
Under the background of the quick development of lightweight, flexible, and wearable electronic devices in our society, a flexible and highly efficient energy management strategy is needed for their counterpart energy-storage systems. Among them, flexible electrochemical capacitors (ECs) have been considered as one of the most promising candidates because of their significant advantages in power and energy densities, and unique properties of being flexible, lightweight, low-cost, and environmentally friendly compared with current energy storage devices. In a common EC, carbon materials play an irreplaceable and principal role in its energy-storage performance. Up till now, most progress towards flexible ECs technologies has mostly benefited from the continuous development of carbon materials. As a result, in view of the dual remarkable highlights of ECs and carbon materials, a summary of recent research progress on carbon-based flexible EC electrode materials is presented in this review, including carbon fiber (CF, consisting of carbon microfiber-CMF and carbon nanofiber-CNF) networks, carbon nanotube (CNT) and graphene coatings, CNT and/or graphene papers (or films), and freestanding three-dimensional (3D) flexible carbon-based macroscopic architectures. Furthermore, some promising carbon materials for great potential applications in flexible ECs are introduced. Finally, the trends and challenges in the development of carbon-based electrode materials for flexible ECs and their smart applications are analyzed.
Wang, Hou; Yuan, Xingzhong; Zeng, Guangming; Wu, Yan; Liu, Yang; Jiang, Qian; Gu, Shansi
2015-07-01
With superior electrical/thermal conductivities and mechanical properties, two dimensional (2D) graphene has become one of the most intensively explored carbon allotropes in materials science. To exploit the inherent properties fully, 2D graphene sheets are often fabricated or assembled into functional architectures (e.g. hydrogels, aerogels) with desired three dimensional (3D) interconnected porous microstructures. The 3D graphene based materials show many excellent characteristics including increased active material per projected area, accessible mass transport or storage, electro/thermo conductivity, chemical/electrochemical stability and flexibility. It has paved the way for practical requirements in electronics, adsorption as well as catalysis related system. This review shows an extensive overview of the main principles and the recent synthetic technologies about fabricating various innovative 3D graphene based materials. Subsequently, recent progresses in electrochemical energy devices (lithium/lithium ion batteries, supercapacitors, fuel cells and solar cells) and hydrogen energy generation/storage are explicitly discussed. The up to date advances for pollutants detection and environmental remediation are also reviewed. Finally, challenges and outlooks in materials development for energy and environment are suggested. Copyright © 2015 Elsevier B.V. All rights reserved.
All-inkjet-printed flexible ZnO micro photodetector for a wearable UV monitoring device
NASA Astrophysics Data System (ADS)
Tran, Van-Thai; Wei, Yuefan; Yang, Hongyi; Zhan, Zhaoyao; Du, Hejun
2017-03-01
Fabrication of small-sized patterns of inorganic semiconductor onto flexible substrates is a major concern when manufacturing wearable devices for measuring either biometric or environmental parameters. In this study, micro-sized flexible ZnO UV photodetectors have been thoroughly prepared by a facile inkjet printing technology and followed with heat treatments. A simple ink recipe of zinc acetate precursor solution was investigated. It is found that the substrate temperature during zinc precursor ink depositing has significant effects on ZnO pattern shape, film morphology, and crystallization. The device fabricated from the additive manufacturing approach has good bendability, Ohmic contact, short response time as low as 0.3 s, and high on/off ratio of 3525. We observed the sensor’s dependence of response/decay time by the illuminating UV light intensity. The whole process is based on additive manufacturing which has many benefits such as rapid prototyping, saving material, being environmentally friendly, and being capable of creating high-resolution patterns. In addition, this method can be applied to flexible substrates, which makes the device more applicable for applications requiring flexibility such as wearable devices. The proposed all-inkjet-printing approach for a micro-sized ZnO UV photodetector would significantly simplify the fabrication process of micro-sized inorganic semiconductor-based devices. A potential application is real-time monitoring of UV light exposure to warn users about unsafe direct sunlight to implement suitable avoidance solutions.
NASA Astrophysics Data System (ADS)
Farrell, Mikella E.; Holthoff, Ellen L.; Pellegrino, Paul M.
2015-05-01
The requirement to detect hazardous materials (i.e., chemical, biological, and explosive) on a host of materials has led to the development of hazard detection systems. These new technologies and their capabilities could have immediate uses for the US military, national security agencies, and environmental response teams in efforts to keep people secure and safe. In particular, due to the increasing use by terrorists, the detection of common explosives and improvised explosive device (IED) materials have motivated research efforts toward detecting trace (i.e., particle level) quantities on multiple commonly encountered surfaces (e.g., textiles, metals, plastics, natural products, and even people). Non-destructive detection techniques can detect trace quantities of explosive materials; however, it can be challenging in the presence of a complex chemical background. One spectroscopic technique gaining increased attention for detection is Raman. One popular explosive precursor material is ammonium nitrate (AN). The material AN has many agricultural applications, however it can also be used in the fabrication of IEDs or homemade explosives (HMEs). In this paper, known amounts of AN will be deposited using an inkjet printer into several different common material surfaces (e.g., wood, human hair, textiles, metals, plastics). The materials are characterized with microscope images and by collecting Raman spectral data. In this report the detection and identification of AN will be demonstrated.
MISSE-X: An ISS External Platform for Space Environmental Studies in the Post-Shuttle Era
NASA Technical Reports Server (NTRS)
Thibeault, Sheila A.; Cooke, Stuart A.; Ashe, Melissa P.; Saucillo, Rudolph J.; Murphy, Douglas G.; deGroh, Kim K.; Jaworske, Donald A.; Nguyen, Quang-Viet
2011-01-01
Materials International Space Station Experiment-X (MISSE-X) is a proposed International Space Station (ISS) external platform for space environmental studies designed to advance the technology readiness of materials and devices critical for future space exploration. The MISSE-X platform will expand ISS utilization by providing experimenters with unprecedented low-cost space access and return on investment (ROI). As a follow-on to the highly successful MISSE series of ISS experiments, MISSE-X will provide advances over the original MISSE configurations including incorporation of plug-and-play experiments that will minimize return mass requirements in the post-Shuttle era, improved active sensing and monitoring of the ISS external environment for better characterization of environmental effects, and expansion of the MISSE-X user community through incorporation of new, customer-desired capabilities. MISSE-X will also foster interest in science, technology, engineering, and math (STEM) in primary and secondary schools through student collaboration and participation.1,2
Manufacturing considerations for AMLCD cockpit displays
NASA Astrophysics Data System (ADS)
Luo, Fang-Chen
1995-06-01
AMLCD cockpit displays need to meet more stringent requirements compared with AMLCD commercial displays in areas such as environmental conditions, optical performance and device reliability. Special considerations are required for the manufacturing of AMLCD cockpit displays in each process step to address these issues. Some examples are: UV stable polarizers, wide-temperature LC material, strong LC glue seal, ESS test system, gray scale voltage EEPROM, etc.
Progress in the development and integration of fluid flow control tools in paper microfluidics.
Fu, Elain; Downs, Corey
2017-02-14
Paper microfluidics is a rapidly growing subfield of microfluidics in which paper-like porous materials are used to create analytical devices. There is a need for higher performance field-use tests for many application domains including human disease diagnosis, environmental monitoring, and veterinary medicine. A key factor in creating high performance paper-based devices is the ability to manipulate fluid flow within the devices. This critical review is focused on the progress that has been made in (i) the development of fluid flow control tools and (ii) the integration of those tools into paper microfluidic devices. Further, we strive to be comprehensive in our presentation and provide historical context through discussion and performance comparisons, when possible, of both relevant earlier work and recent work. Finally, we discuss the major areas of focus for fluid flow methods development to advance the potential of paper microfluidics for high-performance field applications.
An aptamer-based paper microfluidic device for the colorimetric determination of cocaine.
Wang, Ling; Musile, Giacomo; McCord, Bruce R
2018-02-01
A method utilizing paper microfluidics coupled with gold nanoparticles and two anticocaine aptamers has been developed to detect seized cocaine samples. The ready-to-use format involves the use of a paper strip that produces a color change resulting from the salt-induced aggregation of gold nanoparticles producing a visible color change indicating the presence of the drug. This format is specific for the detection of cocaine. The visual LOD for the method was 2.5 μg and the camera based LOD was 2.36 μg. The operation of the device is easy and rapid, and does not require extensive training or instrumentation. All of the materials utilized in the device are safe and environmental friendly. This device should prove a useful tool for the screening of forensic samples. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Zhou, Nanjia; Kim, Myung-Gil; Loser, Stephen; Smith, Jeremy; Yoshida, Hiroyuki; Guo, Xugang; Song, Charles; Jin, Hosub; Chen, Zhihua; Yoon, Seok Min; Freeman, Arthur J.; Chang, Robert P. H.; Facchetti, Antonio; Marks, Tobin J.
2015-01-01
In diverse classes of organic optoelectronic devices, controlling charge injection, extraction, and blocking across organic semiconductor–inorganic electrode interfaces is crucial for enhancing quantum efficiency and output voltage. To this end, the strategy of inserting engineered interfacial layers (IFLs) between electrical contacts and organic semiconductors has significantly advanced organic light-emitting diode and organic thin film transistor performance. For organic photovoltaic (OPV) devices, an electronically flexible IFL design strategy to incrementally tune energy level matching between the inorganic electrode system and the organic photoactive components without varying the surface chemistry would permit OPV cells to adapt to ever-changing generations of photoactive materials. Here we report the implementation of chemically/environmentally robust, low-temperature solution-processed amorphous transparent semiconducting oxide alloys, In-Ga-O and Ga-Zn-Sn-O, as IFLs for inverted OPVs. Continuous variation of the IFL compositions tunes the conduction band minima over a broad range, affording optimized OPV power conversion efficiencies for multiple classes of organic active layer materials and establishing clear correlations between IFL/photoactive layer energetics and device performance. PMID:26080437
Zhou, Nanjia; Kim, Myung -Gil; Loser, Stephen; ...
2015-06-15
In diverse classes of organic optoelectronic devices, controlling charge injection, extraction, and blocking across organic semiconductor– inorganic electrode interfaces is crucial for enhancing quantum efficiency and output voltage. To this end, the strategy of inserting engineered interfacial layers (IFLs) between electrical contacts and organic semiconductors has significantly advanced organic light-emitting diode and organic thin film transistor performance. For organic photovoltaic (OPV) devices, an electronically flexible IFL design strategy to incrementally tune energy level matching between the inorganic electrode system and the organic photoactive components without varying the surface chemistry would permit OPV cells to adapt to ever-changing generations of photoactivemore » materials. Here we report the implementation of chemically/environmentally robust, low-temperature solution-processed amorphous transparent semiconducting oxide alloys, In-Ga-O and Ga-Zn-Sn-O, as IFLs for inverted OPVs. Lastly, continuous variation of the IFL compositions tunes the conduction band minima over a broad range, affording optimized OPV power conversion efficiencies for multiple classes of organic active layer materials and establishing clear correlations between IFL/photoactive layer energetics and device performance.« less
Zhou, Nanjia; Kim, Myung-Gil; Loser, Stephen; Smith, Jeremy; Yoshida, Hiroyuki; Guo, Xugang; Song, Charles; Jin, Hosub; Chen, Zhihua; Yoon, Seok Min; Freeman, Arthur J; Chang, Robert P H; Facchetti, Antonio; Marks, Tobin J
2015-06-30
In diverse classes of organic optoelectronic devices, controlling charge injection, extraction, and blocking across organic semiconductor-inorganic electrode interfaces is crucial for enhancing quantum efficiency and output voltage. To this end, the strategy of inserting engineered interfacial layers (IFLs) between electrical contacts and organic semiconductors has significantly advanced organic light-emitting diode and organic thin film transistor performance. For organic photovoltaic (OPV) devices, an electronically flexible IFL design strategy to incrementally tune energy level matching between the inorganic electrode system and the organic photoactive components without varying the surface chemistry would permit OPV cells to adapt to ever-changing generations of photoactive materials. Here we report the implementation of chemically/environmentally robust, low-temperature solution-processed amorphous transparent semiconducting oxide alloys, In-Ga-O and Ga-Zn-Sn-O, as IFLs for inverted OPVs. Continuous variation of the IFL compositions tunes the conduction band minima over a broad range, affording optimized OPV power conversion efficiencies for multiple classes of organic active layer materials and establishing clear correlations between IFL/photoactive layer energetics and device performance.
DIY Weights and Measures: Developing Your Own Calibration Methods Using Available Materials
NASA Astrophysics Data System (ADS)
Marchetto, P.
2017-12-01
In most cases, when a custom device is built, when an instrument arrives from the manufacturer, or when a piece of equipment is picked up from the store, it is assumed that it will just work, and that data from it will be completely reliable. This fundamental expectation by many scientists is completely unfounded. Between shipping, variable environmental conditions, and many other factors, sensing systems and instruments will be out of tolerance when used. In order to get them back in tolerance, or to at least find out what their uncertainties are, characterization is necessary. If adjustment to the device is possible, this is carried out and called a calibration. In this work, several ways of generating characterization and adjustment methods are discussed, with acoustic, hydraulic, and meteorological devices as examples.
NASA Astrophysics Data System (ADS)
Hu, Zhaoying; Tulevski, George S.; Hannon, James B.; Afzali, Ali; Liehr, Michael; Park, Hongsik
2015-06-01
Carbon nanotubes (CNTs) have been widely studied as a channel material of scaled transistors for high-speed and low-power logic applications. In order to have sufficient drive current, it is widely assumed that CNT-based logic devices will have multiple CNTs in each channel. Understanding the effects of the number of CNTs on device performance can aid in the design of CNT field-effect transistors (CNTFETs). We have fabricated multi-CNT-channel CNTFETs with an 80-nm channel length using precise self-assembly methods. We describe compact statistical models and Monte Carlo simulations to analyze failure probability and the variability of the on-state current and threshold voltage. The results show that multichannel CNTFETs are more resilient to process variation and random environmental fluctuations than single-CNT devices.
NASA Astrophysics Data System (ADS)
Hicks, S. D.; Aufdenkampe, A. K.; Horsburgh, J. S.; Arscott, D. B.; Muenz, T.; Bressler, D. W.
2016-12-01
The explosion in DIY open-source hardware and software has resulted in the development of affordable and accessible technologies, like drones and weather stations, that can greatly assist the general public in monitoring environmental health and its degradation. It is widely recognized that education and support of audiences in pursuit of STEM literacy and the application of emerging technologies is a challenge for the future of citizen science and for preparing high school graduates to be actively engaged in environmental stewardship. It is also clear that detecting environmental change/degradation over time and space will be greatly enhanced with expanded use of networked, remote monitoring technologies by watershed organizations and citizen scientists if data collection and reporting are properly carried out and curated. However, there are few focused efforts to link citizen scientists and school programs with these emerging tools. We have started a multi-year program to develop hardware and teaching materials for training students and citizen scientists about the use of open source hardware in environmental monitoring. Scientists and educators around the world have started building their own dataloggers and devices using a variety of boards based on open source electronics. This new hardware is now providing researchers with an inexpensive alternative to commercial data logging and transmission hardware. We will present a variety of hardware solutions using the Arduino-compatible EnviroDIY Mayfly board (http://envirodiy.org/mayfly) that can be used to build and deploy a rugged environmental monitoring station using a wide variety of sensors and options, giving the users a fully customizable device for making measurements almost anywhere. A database and visualization system is being developed that will allow the users to view and manage the data their devices are collecting. We will also present our plan for developing curricula and leading workshops to various school programs and citizen scientist groups to teach them how to build, deploy, and maintain their own environmental monitoring stations.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Moberg, Asa, E-mail: asa.moberg@infra.kth.s; STFI-Packforsk, PO Box 5604, SE 114 86 Stockholm; KTH, Royal Institute of Technology, Centre for Sustainable Communications, SE 100 44 Stockholm
2010-04-15
Viable alternatives to conventional newspapers, such as electronic papers, e-papers or e-readers, are intended to have many of the qualities of paper, such as reading using reflective light, high resolution, 180 deg. viewing angle. It has been suggested that the environmental impact of e-paper can be lower than for printed and internet-based newspapers. However, in order to find the facts of the matter, a thorough life cycle perspective covering raw material acquisition, production, use and disposal should preferably be used to study the environmental performance of the different products. A screening life cycle assessment was performed to describe the potentialmore » environmental impacts of two product systems; printed on paper and tablet e-paper newspapers. Results show that the most significant phase of the life cycle for both product systems was the production of substrate or platform. Accordingly, key aspects that may affect the resulting environmental performance of newspaper product systems were for the printed newspaper number of readers per copy and number of pages per issue and for the tablet e-paper newspaper lifetime and multi-use of the device. The printed newspaper in general had a higher energy use, higher emissions of gases contributing to climate change and several other impact categories than the tablet e-paper newspaper. It was concluded that tablet e-paper has the potential to decrease the environmental impact of newspaper consumption. However, further studies regarding the environmental impact of production and waste management of electronic devices and internet use, as well as more comprehensive assessment of toxicological impacts are needed. As the data on the electronic devices becomes more comprehensive this may prove to be a major limitation of electronic newspaper systems. Developers are suggested to strive towards minimisation of toxic and rare substances in production.« less
Electrospinning of Nanofibers for Energy Applications
Sun, Guiru; Sun, Liqun; Xie, Haiming; Liu, Jia
2016-01-01
With global concerns about the shortage of fossil fuels and environmental issues, the development of efficient and clean energy storage devices has been drastically accelerated. Nanofibers are used widely for energy storage devices due to their high surface areas and porosities. Electrospinning is a versatile and efficient fabrication method for nanofibers. In this review, we mainly focus on the application of electrospun nanofibers on energy storage, such as lithium batteries, fuel cells, dye-sensitized solar cells and supercapacitors. The structure and properties of nanofibers are also summarized systematically. The special morphology of nanofibers prepared by electrospinning is significant to the functional materials for energy storage. PMID:28335256
Optical silicones for use in harsh operating environments
NASA Astrophysics Data System (ADS)
Riegler, Bill; Bruner, Stephen J.; Elgin, Randall
2004-12-01
The optics industry widely uses silcones for various fiber optic cable potting applications and light emitting diode protection. Optics manufacturers know traditional silicone elastomers, gels, thixotropic gels, and fluids not only perform extremely well in high temperature applications, but also offer refractive index matching so that silicones can transmit light with admirable efficiency. However, because environmental conditions may affect a material's performance over time, one must also consider the conditions the device operates in to ensure long-term reliability. External environments may include exposure to a combination of UV light and temperature, while other environments may expose devices to hydrocarbon based fuels. This paper will delve into the chemistry of silicones and functional groups that lend themselves to properties such as temperature, fuel, and radiation resistance to show shy silicone is the material of choice for optic applications under normally harmful forms of exposure. Data will be presented to examine silicone's performance in these environment.
Impact of Environmental Enrichment Devices on NTP In Vivo Studies
Churchill, Sheba R.; Morgan, Daniel L.; Kissling, Grace E.; Travlos, Gregory S.; King-Herbert, Angela P.
2015-01-01
The goal of this study was to determine whether the use of nesting material or polycarbonate shelters, as enrichment devices would have an impact on endpoints commonly measured during the conduct of the National Toxicology Program (NTP) 13-week studies. The study design was consistent with the NTP 13-week toxicity studies. Harlan Sprague Dawley (HSD) rats and their offspring, and B6C3F1/N mice were assigned to control (unenriched) and enriched experimental groups. Body weight, food and water consumption, behavioral observations, fecal content, clinical pathology, gross pathology, organ weights, and histopathology were evaluated. Enriched male mice and male and female rats exhibited decreased feed intake without a subsequent decrease in body weight; this may have been the result of the nesting material reducing the effect of cold stress thereby allowing for more efficient use of feed. There were statistical differences in some hematological parameters, however these were not considered physiologically relevant since all values were within the normal range. Gross pathology and histopathological findings were background changes and were not considered enrichment-related. Nesting material and shelters were used frequently and consistently and allowed animals to display species typical behavior. There was no significant impact on commonly measured endpoints in HSD rats and B6C3F1/N mice given enrichment devices. PMID:26873679
Black phosphorus ink formulation for inkjet printing of optoelectronics and photonics.
Hu, Guohua; Albrow-Owen, Tom; Jin, Xinxin; Ali, Ayaz; Hu, Yuwei; Howe, Richard C T; Shehzad, Khurram; Yang, Zongyin; Zhu, Xuekun; Woodward, Robert I; Wu, Tien-Chun; Jussila, Henri; Wu, Jiang-Bin; Peng, Peng; Tan, Ping-Heng; Sun, Zhipei; Kelleher, Edmund J R; Zhang, Meng; Xu, Yang; Hasan, Tawfique
2017-08-17
Black phosphorus is a two-dimensional material of great interest, in part because of its high carrier mobility and thickness dependent direct bandgap. However, its instability under ambient conditions limits material deposition options for device fabrication. Here we show a black phosphorus ink that can be reliably inkjet printed, enabling scalable development of optoelectronic and photonic devices. Our binder-free ink suppresses coffee ring formation through induced recirculating Marangoni flow, and supports excellent consistency (< 2% variation) and spatial uniformity (< 3.4% variation), without substrate pre-treatment. Due to rapid ink drying (< 10 s at < 60 °C), printing causes minimal oxidation. Following encapsulation, the printed black phosphorus is stable against long-term (> 30 days) oxidation. We demonstrate printed black phosphorus as a passive switch for ultrafast lasers, stable against intense irradiation, and as a visible to near-infrared photodetector with high responsivities. Our work highlights the promise of this material as a functional ink platform for printed devices.Atomically thin black phosphorus shows promise for optoelectronics and photonics, yet its instability under environmental conditions and the lack of well-established large-area synthesis protocols hinder its applications. Here, the authors demonstrate a stable black phosphorus ink suitable for printed ultrafast lasers and photodetectors.
Factors affecting microbial adhesion to stainless steel and other materials used in medical devices.
Verran, J; Whitehead, K
2005-11-01
The role of biofilm in medical device associated infections is well documented. Biofilms are more resistant to antibiotics than planktonic cells, these are extremely difficult to treat. Prevention strategies include efforts to insert implants under stringent aseptic conditions, and also encompass the development of novel materials which interfere with the initial attachment of microorganisms to the surface of the device. Microbial cells also attach onto hygienic surfaces in the hospital setting, and thereby pose a cross-infection problem. In this case, vigorous cleaning and sanitizing regimes may be employed in addition to any surface modifications. Many factors affect the initial attachment of organisms to inert substrata, and their subsequent retention or removal/detachment, including the physical and chemical nature and location of the substratum, the type of organic material and microorganisms potentially fouling the surface, and the nature of the interface (solid-liquid in the body; solid-air on environmental surfaces). Focusing on one factor, surface topography, it is apparent that many further variables need to be defined in order to fully understand the interactions occurring between the cell and surface. It is therefore important when modifying one substratum surface property in order to reduce adhesion, to also consider other potentially confounding factors.
Environment, health and safety issues for sources used in MOVPE growth of compound semiconductors
NASA Astrophysics Data System (ADS)
Shenai-Khatkhate, Deodatta V.; Goyette, Randall J.; DiCarlo, Ronald L., Jr.; Dripps, Gregory
2004-12-01
As metalorganic vapor-phase epitaxy (MOVPE) is becoming well-established production technology, there are equally growing concerns associated with its bearing on personnel and community safety, environmental impact and maximum quantities of hazardous materials permissible in the device fabrication operations. Safety as well as responsible environmental care has always been of paramount importance in the MOVPE-based crystal growth of compound semiconductors. In this paper, we present the findings from workplace exposure monitoring studies on conventional MOVPE sources such as trimethylgallium, triethylgallium, trimethylantimony and diethylzinc. Also reviewed are the environmental, health and safety hazard aspects for metalorganic sources of routine elements, and the means to minimize the risks (i.e., engineering controls) involved while using these MOVPE sources.
Recent Progress in Biosensors for Environmental Monitoring: A Review
2017-01-01
The environmental monitoring has been one of the priorities at the European and global scale due to the close relationship between the environmental pollution and the human health/socioeconomic development. In this field, the biosensors have been widely employed as cost-effective, fast, in situ, and real-time analytical techniques. The need of portable, rapid, and smart biosensing devices explains the recent development of biosensors with new transduction materials, obtained from nanotechnology, and for multiplexed pollutant detection, involving multidisciplinary experts. This review article provides an update on recent progress in biosensors for the monitoring of air, water, and soil pollutants in real conditions such as pesticides, potentially toxic elements, and small organic molecules including toxins and endocrine disrupting chemicals. PMID:29244756
Recent Progress in Biosensors for Environmental Monitoring: A Review.
Justino, Celine I L; Duarte, Armando C; Rocha-Santos, Teresa A P
2017-12-15
The environmental monitoring has been one of the priorities at the European and global scale due to the close relationship between the environmental pollution and the human health/socioeconomic development. In this field, the biosensors have been widely employed as cost-effective, fast, in situ, and real-time analytical techniques. The need of portable, rapid, and smart biosensing devices explains the recent development of biosensors with new transduction materials, obtained from nanotechnology, and for multiplexed pollutant detection, involving multidisciplinary experts. This review article provides an update on recent progress in biosensors for the monitoring of air, water, and soil pollutants in real conditions such as pesticides, potentially toxic elements, and small organic molecules including toxins and endocrine disrupting chemicals.
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.
Exploration of microfluidic devices based on multi-filament threads and textiles: A review
Nilghaz, A.; Ballerini, D. R.; Shen, W.
2013-01-01
In this paper, we review the recent progress in the development of low-cost microfluidic devices based on multifilament threads and textiles for semi-quantitative diagnostic and environmental assays. Hydrophilic multifilament threads are capable of transporting aqueous and non-aqueous fluids via capillary action and possess desirable properties for building fluid transport pathways in microfluidic devices. Thread can be sewn onto various support materials to form fluid transport channels without the need for the patterned hydrophobic barriers essential for paper-based microfluidic devices. Thread can also be used to manufacture fabrics which can be patterned to achieve suitable hydrophilic-hydrophobic contrast, creating hydrophilic channels which allow the control of fluids flow. Furthermore, well established textile patterning methods and combination of hydrophilic and hydrophobic threads can be applied to fabricate low-cost microfluidic devices that meet the low-cost and low-volume requirements. In this paper, we review the current limitations and shortcomings of multifilament thread and textile-based microfluidics, and the research efforts to date on the development of fluid flow control concepts and fabrication methods. We also present a summary of different methods for modelling the fluid capillary flow in microfluidic thread and textile-based systems. Finally, we summarized the published works of thread surface treatment methods and the potential of combining multifilament thread with other materials to construct devices with greater functionality. We believe these will be important research focuses of thread- and textile-based microfluidics in future. PMID:24086179
Hess, Allison E.; Potter, Kelsey A.; Tyler, Dustin J.; Zorman, Christian A.; Capadona, Jeffrey R.
2013-01-01
Implantable microdevices are gaining significant attention for several biomedical applications1-4. Such devices have been made from a range of materials, each offering its own advantages and shortcomings5,6. Most prominently, due to the microscale device dimensions, a high modulus is required to facilitate implantation into living tissue. Conversely, the stiffness of the device should match the surrounding tissue to minimize induced local strain7-9. Therefore, we recently developed a new class of bio-inspired materials to meet these requirements by responding to environmental stimuli with a change in mechanical properties10-14. Specifically, our poly(vinyl acetate)-based nanocomposite (PVAc-NC) displays a reduction in stiffness when exposed to water and elevated temperatures (e.g. body temperature). Unfortunately, few methods exist to quantify the stiffness of materials in vivo15, and mechanical testing outside of the physiological environment often requires large samples inappropriate for implantation. Further, stimuli-responsive materials may quickly recover their initial stiffness after explantation. Therefore, we have developed a method by which the mechanical properties of implanted microsamples can be measured ex vivo, with simulated physiological conditions maintained using moisture and temperature control13,16,17. To this end, a custom microtensile tester was designed to accommodate microscale samples13,17 with widely-varying Young's moduli (range of 10 MPa to 5 GPa). As our interests are in the application of PVAc-NC as a biologically-adaptable neural probe substrate, a tool capable of mechanical characterization of samples at the microscale was necessary. This tool was adapted to provide humidity and temperature control, which minimized sample drying and cooling17. As a result, the mechanical characteristics of the explanted sample closely reflect those of the sample just prior to explantation. The overall goal of this method is to quantitatively assess the in vivo mechanical properties, specifically the Young's modulus, of stimuli-responsive, mechanically-adaptive polymer-based materials. This is accomplished by first establishing the environmental conditions that will minimize a change in sample mechanical properties after explantation without contributing to a reduction in stiffness independent of that resulting from implantation. Samples are then prepared for implantation, handling, and testing (Figure 1A). Each sample is implanted into the cerebral cortex of rats, which is represented here as an explanted rat brain, for a specified duration (Figure 1B). At this point, the sample is explanted and immediately loaded into the microtensile tester, and then subjected to tensile testing (Figure 1C). Subsequent data analysis provides insight into the mechanical behavior of these innovative materials in the environment of the cerebral cortex. PMID:23995288
Electronic waste management approaches: An overview
DOE Office of Scientific and Technical Information (OSTI.GOV)
Kiddee, Peeranart; Cooperative Research Centre for Contamination Assessment and Remediation of the Environment, Mawson Lakes Campus, Adelaide, SA 5095; Naidu, Ravi, E-mail: ravi.naidu@crccare.com
2013-05-15
Highlights: ► Human toxicity of hazardous substances in e-waste. ► Environmental impacts of e-waste from disposal processes. ► Life Cycle Assessment (LCA), Material Flow Analysis (MFA), Multi Criteria Analysis (MCA) and Extended Producer Responsibility (EPR) to and solve e-waste problems. ► Key issues relating to tools managing e-waste for sustainable e-waste management. - Abstract: Electronic waste (e-waste) is one of the fastest-growing pollution problems worldwide given the presence if a variety of toxic substances which can contaminate the environment and threaten human health, if disposal protocols are not meticulously managed. This paper presents an overview of toxic substances present inmore » e-waste, their potential environmental and human health impacts together with management strategies currently being used in certain countries. Several tools including Life Cycle Assessment (LCA), Material Flow Analysis (MFA), Multi Criteria Analysis (MCA) and Extended Producer Responsibility (EPR) have been developed to manage e-wastes especially in developed countries. The key to success in terms of e-waste management is to develop eco-design devices, properly collect e-waste, recover and recycle material by safe methods, dispose of e-waste by suitable techniques, forbid the transfer of used electronic devices to developing countries, and raise awareness of the impact of e-waste. No single tool is adequate but together they can complement each other to solve this issue. A national scheme such as EPR is a good policy in solving the growing e-waste problems.« less
Bimodal benefits on objective and subjective outcomes for adult cochlear implant users.
Heo, Ji-Hye; Lee, Jae-Hee; Lee, Won-Sang
2013-09-01
Given that only a few studies have focused on the bimodal benefits on objective and subjective outcomes and emphasized the importance of individual data, the present study aimed to measure the bimodal benefits on the objective and subjective outcomes for adults with cochlear implant. Fourteen listeners with bimodal devices were tested on the localization and recognition abilities using environmental sounds, 1-talker, and 2-talker speech materials. The localization ability was measured through an 8-loudspeaker array. For the recognition measures, listeners were asked to repeat the sentences or say the environmental sounds the listeners heard. As a subjective questionnaire, three domains of Korean-version of Speech, Spatial, Qualities of Hearing scale (K-SSQ) were used to explore any relationships between objective and subjective outcomes. Based on the group-mean data, the bimodal hearing enhanced both localization and recognition regardless of test material. However, the inter- and intra-subject variability appeared to be large across test materials for both localization and recognition abilities. Correlation analyses revealed that the relationships were not always consistent between the objective outcomes and the subjective self-reports with bimodal devices. Overall, this study supports significant bimodal advantages on localization and recognition measures, yet the large individual variability in bimodal benefits should be considered carefully for the clinical assessment as well as counseling. The discrepant relations between objective and subjective results suggest that the bimodal benefits in traditional localization or recognition measures might not necessarily correspond to the self-reported subjective advantages in everyday listening environments.
Wearable Intrinsically Soft, Stretchable, Flexible Devices for Memories and Computing.
Rajan, Krishna; Garofalo, Erik; Chiolerio, Alessandro
2018-01-27
A recent trend in the development of high mass consumption electron devices is towards electronic textiles (e-textiles), smart wearable devices, smart clothes, and flexible or printable electronics. Intrinsically soft, stretchable, flexible, Wearable Memories and Computing devices (WMCs) bring us closer to sci-fi scenarios, where future electronic systems are totally integrated in our everyday outfits and help us in achieving a higher comfort level, interacting for us with other digital devices such as smartphones and domotics, or with analog devices, such as our brain/peripheral nervous system. WMC will enable each of us to contribute to open and big data systems as individual nodes, providing real-time information about physical and environmental parameters (including air pollution monitoring, sound and light pollution, chemical or radioactive fallout alert, network availability, and so on). Furthermore, WMC could be directly connected to human brain and enable extremely fast operation and unprecedented interface complexity, directly mapping the continuous states available to biological systems. This review focuses on recent advances in nanotechnology and materials science and pays particular attention to any result and promising technology to enable intrinsically soft, stretchable, flexible WMC.
Wearable Intrinsically Soft, Stretchable, Flexible Devices for Memories and Computing
Rajan, Krishna; Garofalo, Erik
2018-01-01
A recent trend in the development of high mass consumption electron devices is towards electronic textiles (e-textiles), smart wearable devices, smart clothes, and flexible or printable electronics. Intrinsically soft, stretchable, flexible, Wearable Memories and Computing devices (WMCs) bring us closer to sci-fi scenarios, where future electronic systems are totally integrated in our everyday outfits and help us in achieving a higher comfort level, interacting for us with other digital devices such as smartphones and domotics, or with analog devices, such as our brain/peripheral nervous system. WMC will enable each of us to contribute to open and big data systems as individual nodes, providing real-time information about physical and environmental parameters (including air pollution monitoring, sound and light pollution, chemical or radioactive fallout alert, network availability, and so on). Furthermore, WMC could be directly connected to human brain and enable extremely fast operation and unprecedented interface complexity, directly mapping the continuous states available to biological systems. This review focuses on recent advances in nanotechnology and materials science and pays particular attention to any result and promising technology to enable intrinsically soft, stretchable, flexible WMC. PMID:29382050
Functional Scanning Probe Imaging of Nanostructured Solar Energy Materials
DOE Office of Scientific and Technical Information (OSTI.GOV)
Giridharagopal, Rajiv; Cox, Phillip A.; Ginger, David S.
From hybrid perovskites to semiconducting polymer/fullerene blends for organic photovoltaics, many new materials being explored for energy harvesting and storage exhibit performance characteristics that depend sensitively on their nanoscale morphology. At the same time, rapid advances in the capability and accessibility of scanning probe microscopy methods over the past decade have made it possible to study processing/structure/function relationships ranging from photocurrent collection to photocarrier lifetimes with resolutions on the scale of tens of nanometers or better. Importantly, such scanning probe methods offer the potential to combine measurements of local structure with local function, and they can be implemented to studymore » materials in situ or devices in operando to better understand how materials evolve in time in response to an external stimulus or environmental perturbation. This Account highlights recent advances in the development and application of scanning probe microscopy methods that can help address such questions while filling key gaps between the capabilities of conventional electron microscopy and newer super-resolution optical methods. Focusing on semiconductor materials for solar energy applications, we highlight a range of electrical and optoelectronic scanning probe microscopy methods that exploit the local dynamics of an atomic force microscope tip to probe key properties of the solar cell material or device structure. We discuss how it is possible to extract relevant device properties using noncontact scanning probe methods as well as how these properties guide materials development. Specifically, we discuss intensity-modulated scanning Kelvin probe microscopy (IM-SKPM), time-resolved electrostatic force microscopy (trEFM), frequency-modulated electrostatic force microscopy (FM-EFM), and cantilever ringdown imaging. We explain these developments in the context of classic atomic force microscopy (AFM) methods that exploit the physics of cantilever motion and photocarrier generation to provide robust, nanoscale measurements of materials physics that are correlated with device operation. We predict that the multidimensional data sets made possible by these types of methods will become increasingly important as advances in data science expand capabilities and opportunities for image correlation and discovery.« less
Functional Scanning Probe Imaging of Nanostructured Solar Energy Materials
Giridharagopal, Rajiv; Cox, Phillip A.; Ginger, David S.
2016-08-30
From hybrid perovskites to semiconducting polymer/fullerene blends for organic photovoltaics, many new materials being explored for energy harvesting and storage exhibit performance characteristics that depend sensitively on their nanoscale morphology. At the same time, rapid advances in the capability and accessibility of scanning probe microscopy methods over the past decade have made it possible to study processing/structure/function relationships ranging from photocurrent collection to photocarrier lifetimes with resolutions on the scale of tens of nanometers or better. Importantly, such scanning probe methods offer the potential to combine measurements of local structure with local function, and they can be implemented to studymore » materials in situ or devices in operando to better understand how materials evolve in time in response to an external stimulus or environmental perturbation. This Account highlights recent advances in the development and application of scanning probe microscopy methods that can help address such questions while filling key gaps between the capabilities of conventional electron microscopy and newer super-resolution optical methods. Focusing on semiconductor materials for solar energy applications, we highlight a range of electrical and optoelectronic scanning probe microscopy methods that exploit the local dynamics of an atomic force microscope tip to probe key properties of the solar cell material or device structure. We discuss how it is possible to extract relevant device properties using noncontact scanning probe methods as well as how these properties guide materials development. Specifically, we discuss intensity-modulated scanning Kelvin probe microscopy (IM-SKPM), time-resolved electrostatic force microscopy (trEFM), frequency-modulated electrostatic force microscopy (FM-EFM), and cantilever ringdown imaging. We explain these developments in the context of classic atomic force microscopy (AFM) methods that exploit the physics of cantilever motion and photocarrier generation to provide robust, nanoscale measurements of materials physics that are correlated with device operation. We predict that the multidimensional data sets made possible by these types of methods will become increasingly important as advances in data science expand capabilities and opportunities for image correlation and discovery.« less
FDTD analysis of Aluminum/a-Si:H surface plasmon waveguides
NASA Astrophysics Data System (ADS)
Lourenço, Paulo; Fantoni, Alessandro; Fernandes, Miguel; Vygranenko, Yuri; Vieira, Manuela
2018-02-01
The large majority of surface plasmon resonance based devices use noble metals, namely gold or silver, in their manufacturing process. These metals present low resistivity, which leads to low optical losses in the visible and near infrared spectrum ranges. Gold shows high environmental stability, which is essential for long-term operation, and silver's lower stability can be overcome through the deposition of an alumina layer, for instance. However, their high cost is a limiting factor if the intended target is large scale manufacturing. In this work, it is considered a cost-effective approach through the selection of aluminum as the plasmonic material and hydrogenated amorphous silicon instead of its crystalline counterpart. This surface plasmon resonance device relies on Fano resonance to improve its response to refractive index deviations of the surrounding environment. Fano resonance is highly sensitive to slight changes of the medium, hence the reason we incorporated this interference phenomenon in the proposed device. We report the results obtained when conducting Finite-Difference Time Domain algorithm based simulations on this metal-dielectric-metal structure when the active metal is aluminum, gold and silver. Then, we evaluate their sensitivity, detection accuracy and resolution, and the obtained results for our proposed device show good linearity and similar parameter performance as the ones obtained when using gold or silver as plasmonic materials.
Eisenberg, Daniel A; Yu, Mengjing; Lam, Carl W; Ogunseitan, Oladele A; Schoenung, Julie M
2013-09-15
Copper-indium-gallium-selenium-sulfide (CIGS) thin film photovoltaics are increasingly penetrating the market supply for consumer solar panels. Although CIGS is attractive for producing less greenhouse gas emissions than fossil-fuel based energy sources, CIGS manufacturing processes and solar cell devices use hazardous materials that should be carefully considered in evaluating and comparing net environmental benefits of energy products. Through this research, we present a case study on the toxicity hazards associated with alternative materials selection for CIGS manufacturing. We applied two numeric models, The Green Screen for Safer Chemicals and the Toxic Potential Indicator. To improve the sensitivity of the model outputs, we developed a novel, life cycle thinking based hazard assessment method that facilitates the projection of hazards throughout material life cycles. Our results show that the least hazardous CIGS solar cell device and manufacturing protocol consist of a titanium substrate, molybdenum metal back electrode, CuInS₂ p-type absorber deposited by spray pyrolysis, ZnS buffer deposited by spray ion layer gas reduction, ZnO:Ga transparent conducting oxide (TCO) deposited by sputtering, and the encapsulant polydimethylsiloxane. Copyright © 2013 Elsevier B.V. All rights reserved.
Skin-Inspired Electronics: An Emerging Paradigm.
Wang, Sihong; Oh, Jin Young; Xu, Jie; Tran, Helen; Bao, Zhenan
2018-05-15
Future electronics will take on more important roles in people's lives. They need to allow more intimate contact with human beings to enable advanced health monitoring, disease detection, medical therapies, and human-machine interfacing. However, current electronics are rigid, nondegradable and cannot self-repair, while the human body is soft, dynamic, stretchable, biodegradable, and self-healing. Therefore, it is critical to develop a new class of electronic materials that incorporate skinlike properties, including stretchability for conformable integration, minimal discomfort and suppressed invasive reactions; self-healing for long-term durability under harsh mechanical conditions; and biodegradability for reducing environmental impact and obviating the need for secondary device removal for medical implants. These demands have fueled the development of a new generation of electronic materials, primarily composed of polymers and polymer composites with both high electrical performance and skinlike properties, and consequently led to a new paradigm of electronics, termed "skin-inspired electronics". This Account covers recent important advances in skin-inspired electronics, from basic material developments to device components and proof-of-concept demonstrations for integrated bioelectronics applications. To date, stretchability has been the most prominent focus in this field. In contrast to strain-engineering approaches that extrinsically impart stretchability into inorganic electronics, intrinsically stretchable materials provide a direct route to achieve higher mechanical robustness, higher device density, and scalable fabrication. The key is the introduction of strain-dissipation mechanisms into the material design, which has been realized through molecular engineering (e.g., soft molecular segments, dynamic bonds) and physical engineering (e.g., nanoconfinement effect, geometric design). The material design concepts have led to the successful demonstrations of stretchable conductors, semiconductors, and dielectrics without sacrificing their electrical performance. Employing such materials, innovative device design coupled with fabrication method development has enabled stretchable sensors and displays as input/output components and large-scale transistor arrays for circuits and active matrixes. Strategies to incorporate self-healing into electronic materials are the second focus of this Account. To date, dynamic intermolecular interactions have been the most effective approach for imparting self-healing properties onto polymeric electronic materials, which have been utilized to fabricate self-healing sensors and actuators. Moreover, biodegradability has emerged as an important feature in skin-inspired electronics. The incorporation of degradable moieties along the polymer backbone allows for degradable conducting polymers and the use of bioderived materials has led to the demonstration of biodegradable functional devices, such as sensors and transistors. Finally, we highlight examples of skin-inspired electronics for three major applications: prosthetic e-skins, wearable electronics, and implantable electronics.
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...
Lee, Yoon Kyeung; Kim, Jeonghyun; Kim, Yerim; Kwak, Jean Won; Yoon, Younghee; Rogers, John A
2017-10-01
This study describes a conductive ink formulation that exploits electrochemical sintering of Zn microparticles in aqueous solutions at room temperature. This material system has relevance to emerging classes of biologically and environmentally degradable electronic devices. The sintering process involves dissolution of a surface passivation layer of zinc oxide in CH 3 COOH/H 2 O and subsequent self-exchange of Zn and Zn 2+ at the Zn/H 2 O interface. The chemical specificity associated with the Zn metal and the CH 3 COOH/H 2 O solution is critically important, as revealed by studies of other material combinations. The resulting electrochemistry establishes the basis for a remarkably simple procedure for printing highly conductive (3 × 10 5 S m -1 ) features in degradable materials at ambient conditions over large areas, with key advantages over strategies based on liquid phase (fusion) sintering that requires both oxide-free metal surfaces and high temperature conditions. Demonstrations include printed magnetic loop antennas for near-field communication devices. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Bio-inspired materials for electrochemical devices
NASA Astrophysics Data System (ADS)
Pawlicka, A.; Firmino, A.; Sentanin, F.; Sabadini, R. C.; Jimenez, D. E. Q.; Jayme, C. C.; Mindroiu, M.; Zgarian, R. G.; Tihan, G. T.; Rau, I.; Silva, M. M.; Nogueira, A. F.; Kanicki, J.; Kajzar, F.
2015-10-01
Natural macromolecules are very promising row materials to be used in modern technology including security and defense. They are abundant in nature, easy to extract and possess biocompatibility and biodegradability properties. These materials can be modified throughout chemical or physical processes, and can be doped with lithium and rare earth salts, ionic liquids, organic and inorganic acids. In this communication samples of DNA and modified DNA were doped with Prussian Blue (PB), poly(ethylene dioxythiophene) (PEDOT), europium and erbium triflate and organic dyes such as Nile Blue (NB), Disperse Red 1 (DR1) and Disperse Orange 3 (DO3). The colored or colorless membranes were characterized by electrochemical and spectroscopic measurements, and they were applied in electrochromic devices (ECDs) and dye sensitized solar cells (DSSC). ECDs change the color under applied potential, so they can modulate the intensity of transmitted light of 15 to 35%. As the electrochromic materials, WO3 or Prussian blue (PB), are usually blue colored, the color change is from transparent to blue. DNA, and the complexes: DNA-CTMA, DNA-DODA and DNAPEDOT: PSS were also investigated as either hole carrier material (HTM) or polymer electrolyte in dye-sensitized solar cells (DSSC). The DNA-based samples as HTM in small DSSCs revealed a solar energy conversion efficiency of 0.56%. Polymer electrolytes of DNA-CTMA and DNA-DODA, both with 10 wt% of LiI/I2, applied in small DSSC, exhibited the efficiencies of 0.18 and 0.66%, respectively. The obtained results show that natural macromolecules-based membranes are not only environmentally friendly but are also promising materials to be investigated for several electrochemical devices. However, to obtain better performances more research is still needed.
Extreme-ultraviolet and electron beam lithography processing using water developable resist material
NASA Astrophysics Data System (ADS)
Takei, Satoshi
2017-08-01
In order to achieve the use of pure water in the developable process of extreme-ultraviolet and electron beam lithography, instead of conventionally used tetramethylammonium hydroxide and organic solvents, a water developable resist material was designed and developed. The water-developable resist material was derived from woody biomass with beta-linked disaccharide unit for environmental affair, safety, easiness of handling, and health of the working people. 80 nm dense line patterning images with exposure dose of 22 μC/cm2 and CF4 etching selectivity of 1.8 with hardmask layer were provided by specific process conditions. The approach of our water-developable resist material will be one of the most promising technologies ready to be investigated into production of medical device applications.
NASA Astrophysics Data System (ADS)
Patra, Tarak; Yang, Junhong; Cheng, Yiz; Simmons, David
Polymeric ionic liquids (PILs) are very promising materials to enable more environmentally stable high density energy storage devices. Realization of PILs providing high environmental and mechanical stability while maximizing ion conductivity would be accelerated by an improved molecular level understanding of their structure and dynamics. Extensive evidence suggests that both mechanical properties and ion conductivity in anhydrous PILs are intimately related to the PIL's glass formation behavior. This represents a major challenge to the rational design of these materials, given that the basic nature of glass formation and its connection to molecular properties remains a substantial open question in polymer and condensed matter physics. Here we describe coarse-grained and atomistic molecular dynamics simulations probing the relationship between PIL architecture and interactions, glass formation behavior, and ion transport characteristics. These studies provide guidance towards the design of PILs with improved stability and ion conductivity for future energy applications.
NASA Technical Reports Server (NTRS)
Herz, Richard K.
1990-01-01
Oxidation of CO to CO2 is an important reaction technologically and environmentally and a complex and interesting reaction scientifically. In most cases, the reaction is carried out in order to remove CO as an environmental hazard. A major application of heterogeneous catalysts is catalytic oxidation of CO in the exhaust of combustion devices. The reaction over catalysts in exhaust gas is fast and often mass-transfer-limited since exhaust gases are hot and O2/CO ratios are high. The main challenges to catalyst designers are to control thermal sintering and chemical poisoning of the active materials. The effect of the noble metal on the oxide is discussed, followed by the effect of the oxide on the noble metal, the interaction of the noble metal and oxide to form unique catalytic sites, and the possible ways in which the CO oxidation reaction is catalyzed by the NMRO materials.
Hybrid Integrated Label-Free Chemical and Biological Sensors
Mehrabani, Simin; Maker, Ashley J.; Armani, Andrea M.
2014-01-01
Label-free sensors based on electrical, mechanical and optical transduction methods have potential applications in numerous areas of society, ranging from healthcare to environmental monitoring. Initial research in the field focused on the development and optimization of various sensor platforms fabricated from a single material system, such as fiber-based optical sensors and silicon nanowire-based electrical sensors. However, more recent research efforts have explored designing sensors fabricated from multiple materials. For example, synthetic materials and/or biomaterials can also be added to the sensor to improve its response toward analytes of interest. By leveraging the properties of the different material systems, these hybrid sensing devices can have significantly improved performance over their single-material counterparts (better sensitivity, specificity, signal to noise, and/or detection limits). This review will briefly discuss some of the methods for creating these multi-material sensor platforms and the advances enabled by this design approach. PMID:24675757
Lignin Based Carbon Materials for Energy Storage Applications
DOE Office of Scientific and Technical Information (OSTI.GOV)
Chatterjee, Sabornie; Saito, Tomonori; Rios, Orlando
The implementation of Li-ion battery technology into electric and hybrid electric vehicles and portable electronic devices such as smart phones, laptops and tablets, creates a demand for efficient, economic and sustainable materials for energy storage. However, the high cost and long processing time associated with manufacturing battery-grade anode and cathode materials are two big constraints for lowering the total cost of batteries and environmentally friendly electric vehicles. Lignin, a byproduct of the pulp and paper industry and biorefinery, is one of the most abundant and inexpensive natural biopolymers. It can be efficiently converted to low cost carbon fibers with optimalmore » properties for use as anode materials. Recent developments in the preparation of lignin precursors and conversion to carbon fiber-based anode materials have created a new class of anode materials with excellent electrochemical characteristics suitable for immediate use in existing Li- or Na-ion battery technologies.« less
Hybrid integrated label-free chemical and biological sensors.
Mehrabani, Simin; Maker, Ashley J; Armani, Andrea M
2014-03-26
Label-free sensors based on electrical, mechanical and optical transduction methods have potential applications in numerous areas of society, ranging from healthcare to environmental monitoring. Initial research in the field focused on the development and optimization of various sensor platforms fabricated from a single material system, such as fiber-based optical sensors and silicon nanowire-based electrical sensors. However, more recent research efforts have explored designing sensors fabricated from multiple materials. For example, synthetic materials and/or biomaterials can also be added to the sensor to improve its response toward analytes of interest. By leveraging the properties of the different material systems, these hybrid sensing devices can have significantly improved performance over their single-material counterparts (better sensitivity, specificity, signal to noise, and/or detection limits). This review will briefly discuss some of the methods for creating these multi-material sensor platforms and the advances enabled by this design approach.
Yeo, Eudora S Y; Mathys, Gary I; Brack, Narelle; Thostenson, Erik T; Rider, Andrew N
2017-05-30
Functionalization of carbon nanomaterials is often a critical step that facilitates their integration into larger material systems and devices. In the as-received form, carbon nanomaterials, such as carbon nanotubes (CNTs) or graphene nanoplatelets (GNPs), may contain large agglomerates. Both agglomerates and impurities will diminish the benefits of the unique electrical and mechanical properties offered when CNTs or GNPs are incorporated into polymers or composite material systems. Whilst a variety of methods exist to functionalize carbon nanomaterials and to create stable dispersions, many the processes use harsh chemicals, organic solvents, or surfactants, which are environmentally unfriendly and may increase the processing burden when isolating the nanomaterials for subsequent use. The current research details the use of an alternative, environmentally friendly technique for functionalizing CNTs and GNPs. It produces stable, aqueous dispersions free of harmful chemicals. Both CNTs and GNPs can be added to water at concentrations up to 5 g/L and can be recirculated through a high-powered ultrasonic cell. The simultaneous injection of ozone into the cell progressively oxidizes the carbon nanomaterials, and the combined ultrasonication breaks down agglomerates and immediately exposes fresh material for functionalization. The prepared dispersions are ideally suited for the deposition of thin films onto solid substrates using electrophoretic deposition (EPD). CNTs and GNPs from the aqueous dispersions can be readily used to coat carbon- and glass-reinforcing fibers using EPD for the preparation of hierarchical composite materials.
Fabrication and Performance of Large Format Transition Edge Sensor Microcalorimeter Arrays
NASA Technical Reports Server (NTRS)
Chervenak, James A.; Adams, James S.; Bandler, Simon R.; Busch, Sara E.; Eckart, M. E.; Ewin, A. E.; Finkbeiner, F. M.; Kilbourne, C. A.; Kelley, R. L.; Porst, Jan-Patrick;
2012-01-01
We have produced a variety of superconducting transition edge sensor array designs for microcalorimetric detection of x-rays. Designs include kilopixel scale arrays of relatively small sensors (75 micron pitch) atop a thick metal heatsinking layer as well as arrays of membrane-isolated devices on 250 micron pitch and smaller arrays of devices up to 600 micron pitch. We discuss the fabrication techniques used for each type of array focusing on unique aspects where processes vary to achieve the particular designs and required device parameters. For example, we evaluate various material combinations in the production of the thick metal heatsinking, including superconducting and normal metal adhesion layers. We also evaluate the impact of added heatsinking on the membrane isolated devices as it relates to basic device parameters. Arrays can be characterized with a time division SQUID multiplexer such that greater than 10 devices from an array can be measured in the same cooldown. Device parameters can be measured simultaneously so that environmental events such as thermal drifts or changes in magnetic fields can be controlled. For some designs, we will evaluate the uniformity of parameters impacting the intrinsic performance of the microcalorimeters under bias in these arrays and assess the level of thermal crosstalk.
Cao, Xiehong; Tan, Chaoliang; Zhang, Xiao; Zhao, Wei; Zhang, Hua
2016-08-01
The development of renewable energy storage and conversion devices is one of the most promising ways to address the current energy crisis, along with the global environmental concern. The exploration of suitable active materials is the key factor for the construction of highly efficient, highly stable, low-cost and environmentally friendly energy storage and conversion devices. The ability to prepare two-dimensional (2D) metal dichalcogenide (MDC) nanosheets and their functional composites in high yield and large scale via various solution-based methods in recent years has inspired great research interests in their utilization for renewable energy storage and conversion applications. Here, we will summarize the recent advances of solution-processed 2D MDCs and their hybrid nanomaterials for energy storage and conversion applications, including rechargeable batteries, supercapacitors, electrocatalytic hydrogen generation and solar cells. Moreover, based on the current progress, we will also give some personal insights on the existing challenges and future research directions in this promising field. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
The effects of radiation on the outer planets grand tour
NASA Technical Reports Server (NTRS)
1971-01-01
A handbook is presented which was designed to accompany an oral presentation on the effects of radiation on the outer planets grand tour (OPGT). A summary of OPGT radiation environments expected from natural sources and the radioisotope thermoelectric generators and basic radiation effects and processes are reviewed, and ionization and displacement effects are examined. The presentation summarizes the effects of radiation on miscellaneous spacecraft materials and devices. The annealing and hardening of electronics are described. Special emphasis is placed on microcircuits. Mathematical modeling of circuits affected by radiation and radiation environmental testing are discussed. A review of means of evaluating the performance and correcting failures of irradiated devices is also presented.
An Overview of the Development of Flexible Sensors.
Han, Su-Ting; Peng, Haiyan; Sun, Qijun; Venkatesh, Shishir; Chung, Kam-Sing; Lau, Siu Chuen; Zhou, Ye; Roy, V A L
2017-09-01
Flexible sensors that efficiently detect various stimuli relevant to specific environmental or biological species have been extensively studied due to their great potential for the Internet of Things and wearable electronics applications. The application of flexible and stretchable electronics to device-engineering technologies has enabled the fabrication of slender, lightweight, stretchable, and foldable sensors. Here, recent studies on flexible sensors for biological analytes, ions, light, and pH are outlined. In addition, contemporary studies on device structure, materials, and fabrication methods for flexible sensors are discussed, and a market overview is provided. The conclusion presents challenges and perspectives in this field. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Cellulose-Based Smart Fluids under Applied Electric Fields
Choi, Kisuk; Gao, Chun Yan; Nam, Jae Do
2017-01-01
Cellulose particles, their derivatives and composites have special environmentally benign features and are abundant in nature with their various applications. This review paper introduces the essential properties of several types of cellulose and their derivatives obtained from various source materials, and their use in electro-responsive electrorheological (ER) suspensions, which are smart fluid systems that are actively responsive under applied electric fields, while, at zero electric field, ER fluids retain a liquid-like state. Given the actively controllable characteristics of cellulose-based smart ER fluids under an applied electric field regarding their rheological and dielectric properties, they can potentially be applied for various industrial devices including dampers and haptic devices. PMID:28891966
Henry, Heather F; Suk, William A
2017-03-01
Innovative devices and tools for exposure assessment and remediation play an integral role in preventing exposure to hazardous substances. New solutions for detecting and remediating organic, inorganic, and mixtures of contaminants can improve public health as a means of primary prevention. Using a public health prevention model, detection and remediation technologies contribute to primary prevention as tools to identify areas of high risk (e.g. contamination hotspots), to recognize hazards (bioassay tests), and to prevent exposure through contaminant cleanups. Primary prevention success is ultimately governed by the widespread acceptance of the prevention tool. And, in like fashion, detection and remediation technologies must convey technical and sustainability advantages to be adopted for use. Hence, sustainability - economic, environmental, and societal - drives innovation in detection and remediation technology. The National Institute of Health (NIH) National Institute of Environmental Health Sciences (NIEHS) Superfund Research Program (SRP) is mandated to advance innovative detection, remediation, and toxicity screening technology development through grants to universities and small businesses. SRP recognizes the importance of fast, accurate, robust, and advanced detection technologies that allow for portable real-time, on-site characterization, monitoring, and assessment of contaminant concentration and/or toxicity. Advances in non-targeted screening, biological-based assays, passive sampling devices (PSDs), sophisticated modeling approaches, and precision-based analytical tools are making it easier to quickly identify hazardous "hotspots" and, therefore, prevent exposures. Innovation in sustainable remediation uses a variety of approaches: in situ remediation; harnessing the natural catalytic properties of biological processes (such as bioremediation and phytotechnologies); and application of novel materials science (such as nanotechnology, advanced membranes, new carbon materials, and materials reuse). Collectively, the investment in new technologies shows promise to reduce the amount and toxicity of hazardous substances in the environment. This manuscript highlights SRP funded innovative devices and tools for exposure assessment and remediation of organic, inorganic, and mixtures of contaminants with a particular focus on sustainable technologies.
How The Army Can Be An Environmental Paragon Through Energy
2005-04-01
with recycled energy efficient material . Installing solar heating and solar energy devices on all new buildings will allow water to be heated ...ground heat exchanger , heat pump, and ductwork to deliver the air. The heat exchanger consists of pipes (a loop) buried under the ground close to a...building. Water or water plus antifreeze flows through the heat exchanger pipes absorbing heat (in the winter) and giving up heat (in the summer
Hooper, Bethany; Verdonck, Michele; Amsters, Delena; Myburg, Michelle; Allan, Emily
2017-09-06
Environmental control systems (ECS) are devices that enable people with severe physical limitations to independently control household appliances. Recent advancements in the area of environmental control technology have led to the development of ECS that can be controlled through mainstream smart-devices. There is limited research on ECS within Australia and no known research addressing smart-device ECS. The current study sought to explore users' experiences with smart-device ECS within Australia. The study followed a single embedded case study method. Participants (n = 5) were existing ECS users with a cervical spinal cord injury. Data were collected through semi-structured interviews with participants, reflexive journals and field notes. An inductive approach was used to analyze the data thematically. The experience of using a smart-device ECS presented both opportunities and costs to users. The opportunities included: independent control, choice, peace of mind, connection, effective resource use, and control over smart-phone functions and applications. The associated costs included: financial, time, frustration, and technical limitations. While findings are similar to previous research into traditional ECS this study indicates that smart-device ECS also offered a new opportunity for users to access mainstream smart-device functions and applications. Future research should investigate methods and resources that practitioners could utilize to better support new users of smart-device ECS. Implications for Rehabilitation As with traditional environmental control systems, users of smart environmental control systems report increased independence, choice and control. Smart-device environmental control systems provide users with access to mainstream smart-device functions and applications, which facilitate connection to family and the outside world. The costs to the user of smart-device environmental control systems include monetary and time investment, dealing with technical limitations and resulting frustration. Prescribers and installers must consider ways to mitigate these costs experienced by users.
Waste to energy--key element for sustainable waste management.
Brunner, Paul H; Rechberger, Helmut
2015-03-01
Human activities inevitably result in wastes. The higher the material turnover, and the more complex and divers the materials produced, the more challenging it is for waste management to reach the goals of "protection of men and environment" and "resource conservation". Waste incineration, introduced originally for volume reduction and hygienic reasons, went through a long and intense development. Together with prevention and recycling measures, waste to energy (WTE) facilities contribute significantly to reaching the goals of waste management. Sophisticated air pollution control (APC) devices ensure that emissions are environmentally safe. Incinerators are crucial and unique for the complete destruction of hazardous organic materials, to reduce risks due to pathogenic microorganisms and viruses, and for concentrating valuable as well as toxic metals in certain fractions. Bottom ash and APC residues have become new sources of secondary metals, hence incineration has become a materials recycling facility, too. WTE plants are supporting decisions about waste and environmental management: They can routinely and cost effectively supply information about chemical waste composition as well as about the ratio of biogenic to fossil carbon in MSW and off-gas. Copyright © 2014 Elsevier Ltd. All rights reserved.
A molecular nematic liquid crystalline material for high-performance organic photovoltaics
Sun, Kuan; Xiao, Zeyun; Lu, Shirong; Zajaczkowski, Wojciech; Pisula, Wojciech; Hanssen, Eric; White, Jonathan M.; Williamson, Rachel M.; Subbiah, Jegadesan; Ouyang, Jianyong; Holmes, Andrew B.; Wong, Wallace W.H.; Jones, David J.
2015-01-01
Solution-processed organic photovoltaic cells (OPVs) hold great promise to enable roll-to-roll printing of environmentally friendly, mechanically flexible and cost-effective photovoltaic devices. Nevertheless, many high-performing systems show best power conversion efficiencies (PCEs) with a thin active layer (thickness is ~100 nm) that is difficult to translate to roll-to-roll processing with high reproducibility. Here we report a new molecular donor, benzodithiophene terthiophene rhodanine (BTR), which exhibits good processability, nematic liquid crystalline behaviour and excellent optoelectronic properties. A maximum PCE of 9.3% is achieved under AM 1.5G solar irradiation, with fill factor reaching 77%, rarely achieved in solution-processed OPVs. Particularly promising is the fact that BTR-based devices with active layer thicknesses up to 400 nm can still afford high fill factor of ~70% and high PCE of ~8%. Together, the results suggest, with better device architectures for longer device lifetime, BTR is an ideal candidate for mass production of OPVs. PMID:25586307
Thin film electronic devices with conductive and transparent gas and moisture permeation barriers
Simpson, Lin Jay
2013-12-17
A thin film stack (100, 200) is provided for use in electronic devices such as photovoltaic devices. The stack (100, 200) may be integrated with a substrate (110) such as a light transmitting/transmissive layer. A electrical conductor layer (120, 220) is formed on a surface of the substrate (110) or device layer such as a transparent conducting (TC) material layer (120,220) with pin holes or defects (224) caused by manufacturing. The stack (100) includes a thin film (130, 230) of metal that acts as a barrier for environmental contaminants (226, 228). The metal thin film (130,230) is deposited on the conductor layer (120, 220) and formed from a self-healing metal such as a metal that forms self-terminating oxides. A permeation plug or block (236) is formed in or adjacent to the thin film (130, 230) of metal at or proximate to the pin holes (224) to block further permeation of contaminants through the pin holes (224).
Transient Resistive Switching Devices Made from Egg Albumen Dielectrics and Dissolvable Electrodes.
He, Xingli; Zhang, Jian; Wang, Wenbo; Xuan, Weipeng; Wang, Xiaozhi; Zhang, Qilong; Smith, Charles G; Luo, Jikui
2016-05-04
Egg albumen as the dielectric, and dissolvable Mg and W as the top and bottom electrodes are used to fabricate water-soluble memristors. 4 × 4 cross-bar configuration memristor devices show a bipolar resistive switching behavior with a high to low resistance ratio in the range of 1 × 10(2) to 1 × 10(4), higher than most other biomaterial-based memristors, and a retention time over 10(4) s without any sign of deterioration, demonstrating its high stability and reliability. Metal filaments accompanied by hopping conduction are believed to be responsible for the switching behavior of the memory devices. The Mg and W electrodes, and albumen film all can be dissolved in water within 72 h, showing their transient characteristics. This work demonstrates a new way to fabricate biocompatible and dissolvable electronic devices by using cheap, abundant, and 100% natural materials for the forthcoming bioelectronics era as well as for environmental sensors when the Internet of things takes off.
NDE of polymeric composite material bridge components
NASA Astrophysics Data System (ADS)
Duke, John C., Jr.; Horne, Michael R.
1998-03-01
Rapid advancements with respect to utilization of polymeric composite materials for bridge components is occurring. This situation is driven primarily by the potential improvements offered by these materials with respect to long term durability. However, because of the developmental nature of these materials much of the materials characterization has involved short term testing without the synergistic effects of environmental exposure. Efforts to develop nondestructive evaluation procedures, essential for any wide spread use in critical structural applications, have been consequently limited. This paper discuses the effort to develop NDE methods for field inspection of hybrid glass and carbon fiber reinforced vinyl ester pultruded 'double box' I beams that are installed in a small bridge over Tom's Creek, in Blacksburg, Virginia. Integrated structural element sensors, dormant infrared devices, as well as acousto-ultrasonic methods are under development for detecting and monitoring the occurrence and progression of life limiting deterioration mechanisms.
Metal-free supercapacitor with aqueous electrolyte and low-cost carbon materials
NASA Astrophysics Data System (ADS)
Blomquist, Nicklas; Wells, Thomas; Andres, Britta; Bäckström, Joakim; Forsberg, Sven; Olin, Håkan
2017-01-01
Electric double-layer capacitors (EDLCs) or supercapacitors (SCs) are fast energy storage devices with high pulse efficiency and superior cyclability, which makes them useful in various applications including electronics, vehicles and grids. Aqueous SCs are considered to be more environmentally friendly than those based on organic electrolytes. Because of the corrosive nature of the aqueous environment, however, expensive electrochemically stable materials are needed for the current collectors and electrodes in aqueous SCs. This results in high costs for a given energy-storage capacity. To address this, we developed a novel low-cost aqueous SC using graphite foil as the current collector and a mix of graphene, nanographite, simple water-purification carbons and nanocellulose as electrodes. The electrodes were coated directly onto the graphite foil by using casting frames and the SCs were assembled in a pouch cell design. With this approach, we achieved a material cost reduction of greater than 90% while maintaining approximately one-half of the specific capacitance of a commercial unit, thus demonstrating that the proposed SC can be an environmentally friendly, low-cost alternative to conventional SCs.
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...
Bimodal Benefits on Objective and Subjective Outcomes for Adult Cochlear Implant Users
Heo, Ji-Hye; Lee, Won-Sang
2013-01-01
Background and Objectives Given that only a few studies have focused on the bimodal benefits on objective and subjective outcomes and emphasized the importance of individual data, the present study aimed to measure the bimodal benefits on the objective and subjective outcomes for adults with cochlear implant. Subjects and Methods Fourteen listeners with bimodal devices were tested on the localization and recognition abilities using environmental sounds, 1-talker, and 2-talker speech materials. The localization ability was measured through an 8-loudspeaker array. For the recognition measures, listeners were asked to repeat the sentences or say the environmental sounds the listeners heard. As a subjective questionnaire, three domains of Korean-version of Speech, Spatial, Qualities of Hearing scale (K-SSQ) were used to explore any relationships between objective and subjective outcomes. Results Based on the group-mean data, the bimodal hearing enhanced both localization and recognition regardless of test material. However, the inter- and intra-subject variability appeared to be large across test materials for both localization and recognition abilities. Correlation analyses revealed that the relationships were not always consistent between the objective outcomes and the subjective self-reports with bimodal devices. Conclusions Overall, this study supports significant bimodal advantages on localization and recognition measures, yet the large individual variability in bimodal benefits should be considered carefully for the clinical assessment as well as counseling. The discrepant relations between objective and subjective results suggest that the bimodal benefits in traditional localization or recognition measures might not necessarily correspond to the self-reported subjective advantages in everyday listening environments. PMID:24653909
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...
PROCESS DEVELOPMENT FOR THE RECOVERY OF CRITICAL MATERIALS FROM ELECTRONIC WASTE
DOE Office of Scientific and Technical Information (OSTI.GOV)
Lister, T. E.; Diaz, L. A.; Clark, G. G.
As electronic technology continues to evolve there is a growing need to develop processes which recover valuable material from antiquated technology. This need follows from the environmental challenges associated with the availability of raw materials and fast growing generation of electronic waste. Although just present in small quantities in electronic devices, the availability of raw materials, such as rare earths and precious metals, becomes critical for the production of high tech electronic devices and the development of green technologies (i.e. wind turbines, electric motors, and solar panels). Therefore, the proper recycling and processing of increasing volumes of electronic waste presentmore » an opportunity to stabilize the market of critical materials, reducing the demand of mined products, and providing a proper disposal and treatment of a hazardous waste stream. This paper will describe development and techno-economic assessment of a comprehensive process for the recovery of value and critical materials from electronic waste. This hydrometallurgical scheme aims to selectively recover different value segments in the materials streams (base metals, precious metals, and rare earths). The economic feasibility for the recovery of rare earths from electronic waste is mostly driven by the efficient recovery of precious metals, such as Au and Pd (ca. 80 % of the total recoverable value). Rare earth elements contained in magnets (speakers, vibrators and hard disk storage) can be recovered as a mixture of rare earths oxides which can later be reduced to the production of new magnets.« less
Cadmium-free quantum dot light emitting devices: energy-transfer realizing pure blue emission.
Ji, Wenyu; Jing, Pengtao; Fan, Yi; Zhao, Jialong; Wang, Yunjun; Kong, Xianggui
2013-01-01
In this study, deep blue, pure electroluminescence (EL) at 441.5 nm from a ZnSe/ZnS quantum dot light-emitting device (QD-LED) is obtained by using poly (4-butylphenyl-diphenyl-amine) (poly-TPD) as the hole-transport layer (HTL) to open up the channel for energy transfer from poly-TPD to QDs. The emission originating from HTL is observed in the QD-LED with N,N'-bis (tolyl)-N,N'-diphenyl-1,1'-biphenyl-4,4'-diamine functionalized with two styryl groups (2-TPD) as the HTL due to inefficient energy-transfer from 2-TPD to QDs. The poly-TPD based device exhibits color-saturated blue emission with a narrow spectral bandwidth of full width at half maximum (~17.2 nm). These results explore the operating mechanism of the QD EL and signify a remarkable progress in deep blue QD-LEDs based on environmental-friendly QD materials.
Electrochemical sensors and devices for heavy metals assay in water: the French groups' contribution
Pujol, Luca; Evrard, David; Groenen-Serrano, Karine; Freyssinier, Mathilde; Ruffien-Cizsak, Audrey; Gros, Pierre
2014-01-01
A great challenge in the area of heavy metal trace detection is the development of electrochemical techniques and devices which are user-friendly, robust, selective, with low detection limits and allowing fast analyses. This review presents the major contribution of the French scientific academic community in the field of electrochemical sensors and electroanalytical methods within the last 20 years. From the well-known polarography to the up-to-date generation of functionalized interfaces, the different strategies dedicated to analytical performances improvement are exposed: stripping voltammetry, solid mercury-free electrode, ion selective sensor, carbon based materials, chemically modified electrodes, nano-structured surfaces. The paper particularly emphasizes their advantages and limits face to the last Water Frame Directive devoted to the Environmental Quality Standards for heavy metals. Recent trends on trace metal speciation as well as on automatic “on line” monitoring devices are also evoked. PMID:24818124
Particulate Removal Using a CO2 Composite Spray Cleaning System
NASA Technical Reports Server (NTRS)
Chen, Nicole; Lin, Ying; Jackson, David; Chung, Shirley
2016-01-01
The Planetary Protection surface cleanliness requirements for potential Mars Sample Return hardware that would come in contact with Martian samples may be stricter than previous missions. The Jet Propulsion Laboratory has developed a new technology that will enable us to remove sub-micron size particles from critical hardware surfaces. A hand-held CO2 composite cleaning system was tested to verify its cleaning capabilities. This convenient, portable device can be used in cleanrooms for cleaning after rework or during spacecraft integration and assembly. It is environmentally safe and easy to use. This cleaning concept has the potential to be further developed into a robotic cleaning device on a Mars Lander to be used to clean sample acquisition or sample handling devices in situ. Contaminants of known sizes and concentrations, such as fluorescent microspheres and spores were deposited on common spacecraft material surfaces. The cleaning efficiency results will be presented and discussed.
International Outdoor Experiments and Models for Outdoor Radiological Dispersal Devices
Blumenthal, Daniel J.; Musolino, Stephen V.
2016-05-01
With the advent of nuclear reactors and the technology to produce radioactive materials in large quantities, concern arose about the use of radioactivity as a poison in warfare, and hence, consideration was given to defensive measures (Smyth 1945). Approximately forty years later, the interest in the environmental- and health effects caused by a deliberate dispersal was renewed, but this time, from the perspective of a malevolent act of radiological terrorism in an urban area. For many years there has been international collaboration in scientific research to understand the range of effects that might result from a device that could bemore » constructed by a sub-national group. In this paper, scientists from government laboratories in Australia, Canada, the United Kingdom, and the United States collectively have conducted a myriad of experiments to understand and detail the phenomenology of an explosive radiological dispersal device.« less
Non-Toxic Gold Nanoclusters for Solution-Processed White Light-Emitting Diodes.
Chao, Yu-Chiang; Cheng, Kai-Ping; Lin, Ching-Yi; Chang, Yu-Li; Ko, Yi-Yun; Hou, Tzu-Yin; Huang, Cheng-Yi; Chang, Walter H; Lin, Cheng-An J
2018-06-11
Solution-processed optoelectronic devices are attractive because of the potential low-cost fabrication and the compatibility with flexible substrate. However, the utilization of toxic elements such as lead and cadmium in current optoelectronic devices on the basis of colloidal quantum dots raises environmental concerns. Here we demonstrate that white-light-emitting diodes can be achieved by utilizing non-toxic and environment-friendly gold nanoclusters. Yellow-light-emitting gold nanoclusters were synthesized and capped with trioctylphosphine. These gold nanoclusters were then blended with the blue-light-emitting organic host materials to form the emissive layer. A current efficiency of 0.13 cd/A was achieved. The Commission Internationale de l'Eclairage chromaticity coordinates of (0.27, 0.33) were obtained from our experimental analysis, which is quite close to the ideal pure white emission coordinates (0.33, 0.33). Potential applications include innovative lighting devices and monitor backlight.
Graphene Based Ultra-Capacitors for Safer, More Efficient Energy Storage
NASA Technical Reports Server (NTRS)
Roberson, Luke B.; Mackey, Paul J.; Zide, Carson J.
2016-01-01
Current power storage methods must be continuously improved in order to keep up with the increasingly competitive electronics industry. This technological advancement is also essential for the continuation of deep space exploration. Today's energy storage industry relies heavily on the use of dangerous and corrosive chemicals such as lithium and phosphoric acid. These chemicals can prove hazardous to the user if the device is ruptured. Similarly they can damage the environment if they are disposed of improperly. A safer, more efficient alternative is needed across a wide range of NASA missions. One solution would a solid-state carbon based energy storage device. Carbon is a safer, less environmentally hazardous alternative to current energy storage materials. Using the amorphous carbon nanostructure, graphene, this idea of a safer portable energy is possible. Graphene was electrochemically produced in the lab and several coin cell devices were built this summer to create a working prototype of a solid-state graphene battery.
Nanocomposites Based on Thermoplastic Polymers and Functional Nanofiller for Sensor Applications
Coiai, Serena; Passaglia, Elisa; Pucci, Andrea; Ruggeri, Giacomo
2015-01-01
Thermoplastic polymers like polyolefins, polyesters, polyamide, and styrene polymers are the most representative commodity plastics thanks to their cost-efficient manufacturing processes, excellent thermomechanical properties and their good environmental compatibility, including easy recycling. In the last few decades much effort has been devoted worldwide to extend the applications of such materials by conferring on them new properties through mixing and blending with different additives. In this latter context, nanocomposites have recently offered new exciting possibilities. This review discusses the successful use of nanostructured dispersed substrates in designing new stimuli-responsive nanocomposites; in particular, it provides an updated description of the synthetic routes to prepare nanostructured systems having the typical properties of thermoplastic polymers (continuous matrix), but showing enhanced optical, conductive, and thermal features dependent on the dispersion topology. The controlled nanodispersion of functional labeled clays, noble metal nanoparticles and carbon nanotubes is here evidenced to play a key role in producing hybrid thermoplastic materials that have been used in the design of devices, such as NLO devices, chemiresistors, temperature and deformation sensors.
Energy conversion device with support member having pore channels
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
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
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.
GOES data-collection system instrumentation, installation, and maintenance manual
Blee, J.W.; Herlong, H.E.; Kaufmann, C.D.; Hardee, J.H.; Field, M.L.; Middelburg, R.F.
1986-01-01
The purpose of the manual is to describe the installation, operation, and maintenance of Geostationary Operational Environmental Satellite (GOES) data collection platforms (DCP's) and associated equipment. This manual is not a substitute for DCP manufacturers ' manuals but is additional material that describes the application of data-collection platforms in the Water Resources Division. Power supplies, encoders, antennas, Mini Monitors, voltage analog devices, and the installation of these at streamflow-gaging stations are discussed in detail. (USGS)
DOE Office of Scientific and Technical Information (OSTI.GOV)
Agrawal, Rakesh
2014-09-28
The development of renewable, affordable, and environmentally conscious means of generating energy on a global scale represents a grand challenge of our time. Due to the “permanence” of radiation from the sun, solar energy promises to remain a viable and sustainable power source far into the future. Established single-junction photovoltaic technologies achieve high power conversion efficiencies (pce) near 20% but require complicated manufacturing processes that prohibit the marriage of large-scale throughput (e.g. on the GW scale), profitability, and quality control. Our approach to this problem begins with the synthesis of nanocrystals of semiconductor materials comprising earth abundant elements and characterizedmore » by material and optoelectronic properties ideal for photovoltaic applications, namely Cu2ZnSn(S,Se)4 (CZTSSe). Once synthesized, such nanocrystals are formulated into an ink, coated onto substrates, and processed into completed solar cells in such a way that enables scale-up to high throughput, roll-to-roll manufacturing processes. This project aimed to address the major limitation to CZTSSe solar cell pce’s – the low open-circuit voltage (Voc) reported throughout literature for devices comprised of this material. Throughout the project significant advancements have been made in fundamental understanding of the CZTSSe material and device limitations associated with this material system. Additionally, notable improvements have been made to our nanocrystal based processing technique to alleviate performance limitations due to the identified device limitations. Notably, (1) significant improvements have been made in reducing intra- and inter-nanoparticle heterogeneity, (2) improvements in device performance have been realized with novel cation substitution in Ge-alloyed CZTGeSSe absorbers, (3) systematic analysis of absorber sintering has been conducted to optimize the selenization process for large grain CZTSSe absorbers, (4) novel electrical characterization analysis techniques have been developed to identify significant limitations to traditional electrical characterization of CZTSSe devices, and (5) the developed electrical analysis techniques have been used to identify the role that band gap and electrostatic potential fluctuations have in limiting device performance for this material system. The device modeling and characterization of CZTSSe undertaken with this project have significant implications for the CZTSSe research community, as the identified limitations due to potential fluctuations are expected to be a performance limitation to high-efficiency CZTSSe devices fabricated from all current processing techniques. Additionally, improvements realized through enhanced absorber processing conditions to minimize nanoparticle and large-grain absorber heterogeneity are suggested to be beneficial processing improvements which should be applied to CZTSSe devices fabricated from all processing techniques. Ultimately, our research has indicated that improved performance for CZTSSe will be achieved through novel absorber processing which minimizes defect formation, elemental losses, secondary phase formation, and compositional uniformity in CZTSSe absorbers; we believe this novel absorber processing can be achieved through nanocrystal based processing of CZTSSe which is an active area of research at the conclusion of this award. While significant fundamental understanding of CZTSSe and the performance limitations associated with this material system, as well as notable improvements in the processing of nanocrystal based CZTSSe absorbers, have been achieved under this project, the limitation of two years of research funding towards our goals prevents further significant advancements directly identified through pce. improvements relative to those reported herein. As the characterization and modeling subtask of this project has been the main driving force for understanding device limitations, the conclusions of this analysis have just recently been applied to the processing of nanocrystal based CZTSSe absorbers -- with notable success. We expect the notable fundamental understanding of device limitations and absorber sintering achieved under this project will lead to significant improvements in device performance for CZTSSe devices in the near future for devices fabricated from a variety of processing techniques« less
Kaushal, Rajendra Kumar; Nema, Arvind K
2012-11-01
Electronic communication devices such as mobile phones pose significant environmental risks when disposed of after the end of their useful life. Mobile communication devices are one of the fastest growing contributors to the electronic waste (e-waste) stream. Recent legislative pressure and increasing awareness about the environmental risk associated with the hazardous components of the electronic products warrants the manufacturers to reduce or replace the hazardous materials with alternatives. The present study analyses the economic consequences of reducing or replacing these hazardous materials and the possible response of the consumers. A strategic game theory model has been applied in this paper for manufacturer and consumers considering the cost difference between hazardous substances free (HSF) and hazardous substance (HS) mobile. Results suggest that the HSF mobiles can be a preferred choice of the manufacturers as well as consumers if the cost of disposal of HS mobiles can be internalized and a marginal incentive (e.g. 0.9% for a cost difference to 5%, and 5.3% for a cost difference to 10%) is given. The study further highlights the need for realizing the fact that passing on the incentives to the consumers in order to promote schemes for return back to manufacturer at its end of life for effective reuse and recycling gives higher returns.
Nano-based sensor for assessment of weaponry structural degradation
NASA Astrophysics Data System (ADS)
Brantley, Christina L.; Edwards, Eugene; Ruffin, Paul B.; Kranz, Michael
2016-04-01
Missiles and weaponry-based systems are composed of metal structures that can degrade after prolonged exposure to environmental elements. A particular concern is accumulation of corrosion that generally results from prolonged environmental exposure. Corrosion, defined as the unintended destruction or deterioration of a material due to its interaction with the environment, can negatively affect both equipment and infrastructure. System readiness and safety can be reduced if corrosion is not detected, prevented and managed. The current corrosion recognition methods (Visual, Radiography, Ultrasonics, Eddy Current, and Thermography) are expensive and potentially unreliable. Visual perception is the most commonly used method for determining corrosion in metal. Utilization of an inductance-based sensor system is being proposed as part of the authors' research. Results from this research will provide a more efficient, economical, and non-destructive sensing approach. Preliminary results demonstrate a highly linear degradation within a corrosive environment due to the increased surface area available on the sensor coupon. The inductance of the devices, which represents a volume property of the coupon, demonstrated sensitivity to corrosion levels. The proposed approach allows a direct mass-loss measurement based on the change in the inductance of the coupon when placed in an alternating magnetic field. Prototype devices have demonstrated highly predictable corrosion rates that are easily measured using low-power small electronic circuits and energy harvesting methods to interrogate the sensor. Preliminary testing demonstrates that the device concept is acceptable and future opportunities for use in low power embedded applications are achievable. Key results in this paper include the assessment of typical Army corrosion cost, degradation patterns of varying metal materials, and application of wireless sensors elements.
High Sensitivity, Low Power Nano Sensors and Devices for Chemical Sensing
NASA Technical Reports Server (NTRS)
Li, Jing; Powell, Dan; Getty, Stephanie; Lu, Yi-Jiang
2004-01-01
The chemical sensor market has been projected to grow to better than $40 billion dollars worldwide within the next 10 years. Some of the primary motivations to develop nanostructured chemical sensors are monitoring and control of environmental pollution; improved diagnostics for consumption; improvement in measurement precision and accuracy; and improved detection limits for Homeland security, battlefield environments, and process and quality control of industrial applications. In each of these applications, there is demand for sensitivity, selectivity and stability of environmental and biohazard detection and capture beyond what is currently commercially available. Nanotechnology offers the ability to work at the molecular level, atom by atom, to create large structures with fundamentally new molecular organization. It is essentially concerned with materials, devices, and systems whose structures and components exhibit novel and significantly improved physical, chemical and biological properties, phenomena, and process control due to their nanoscale size. One such nanotechnology-enabled chemical sensor has been developed at NASA Ames leveraging nanostructures, such as single walled carbon nanotubes (SWNTs) and metal oxide nanobelts or nanowires, as a sensing medium bridging a pair of interdigitated electrodes (IDE) realized through a silicon-based microfabrication and micromachining technique. The DE fingers are fabricated on a silicon substrate using standard photolithography and thin film metallization techniques. It is noteworthy that the fabrication techniques employed are not confined to the silicon substrate. Through spin casting and careful substrate selection (i.e. clothing, glass, polymer, etc.), additional degrees of freedom can be exploited to enhance sensitivity or to conform to unique applications. Both in-situ growth of nanostructured materials and casting of nanostructured dispersions were used to produce analogous chemical sensing devices.
NASA Astrophysics Data System (ADS)
Wei, Ying; Yao, Kai; Wang, Xiaofeng; Jiang, Yihua; Liu, Xueyuan; Zhou, Naigen; Li, Fan
2018-01-01
In this paper, we demonstrate the high-performance inverted planar heterojunction perovskite solar cells (PeSCs) based on the novel inorganic hole-transporting layer (HTL) of silver (Ag)-doped NiOx (Ag:NiOx). Density-functional theory (DFT) calculation reveals that Ag prefers to occupy the substitutional Ni site (AgNi) and behaves as an acceptor in NiO lattice. Compared with the pristine NiOx films, appropriate Ag doping can increase the optical transparency, work function, electrical conductivity and hole mobility of NiOx films. Moreover, the CH3NH3PbI3 perovskite films grown on Ag:NiOx exhibit better crystallinity, higher coverage and smoother surface with densely packed larger grains than those grown on the pristine NiOx film. Consequently, the Ag:NiOx HTL boosts the efficiency of the inverted planar heterojunction PeSCs from 13.46% (for the pristine NiOx-based device) to 16.86% (for the 2 at.% Ag:NiOx-based device). Furthermore, the environmental stability of PeSCs based on Ag:NiOx HTL is dramatically improved compared to devices based on organic HTLs and pristine NiOx HTLs. This work provides a simple and effective HTL material system for high-efficient and stable PeSCs.
Strategies to Reduce Greenhouse Gas Emissions from Laparoscopic Surgery.
Thiel, Cassandra L; Woods, Noe C; Bilec, Melissa M
2018-04-01
To determine the carbon footprint of various sustainability interventions used for laparoscopic hysterectomy. We designed interventions for laparoscopic hysterectomy from approaches that sustainable health care organizations advocate. We used a hybrid environmental life cycle assessment framework to estimate greenhouse gas emissions from the proposed interventions. We conducted the study from September 2015 to December 2016 at the University of Pittsburgh (Pittsburgh, Pennsylvania). The largest carbon footprint savings came from selecting specific anesthetic gases and minimizing the materials used in surgery. Energy-related interventions resulted in a 10% reduction in carbon footprint per case but would result in larger savings for the whole facility. Commonly implemented approaches, such as recycling surgical waste, resulted in less than a 5% reduction in greenhouse gases. To reduce the environmental emissions of surgeries, health care providers need to implement a combination of approaches, including minimizing materials, moving away from certain heat-trapping anesthetic gases, maximizing instrument reuse or single-use device reprocessing, and reducing off-hour energy use in the operating room. These strategies can reduce the carbon footprint of an average laparoscopic hysterectomy by up to 80%. Recycling alone does very little to reduce environmental footprint. Public Health Implications. Health care services are a major source of environmental emissions and reducing their carbon footprint would improve environmental and human health. Facilities seeking to reduce environmental footprint should take a comprehensive systems approach to find safe and effective interventions and should identify and address policy barriers to implementing more sustainable practices.
Strategies to Reduce Greenhouse Gas Emissions from Laparoscopic Surgery
Thiel, Cassandra L.; Woods, Noe C.
2018-01-01
Objectives. To determine the carbon footprint of various sustainability interventions used for laparoscopic hysterectomy. Methods. We designed interventions for laparoscopic hysterectomy from approaches that sustainable health care organizations advocate. We used a hybrid environmental life cycle assessment framework to estimate greenhouse gas emissions from the proposed interventions. We conducted the study from September 2015 to December 2016 at the University of Pittsburgh (Pittsburgh, Pennsylvania). Results. The largest carbon footprint savings came from selecting specific anesthetic gases and minimizing the materials used in surgery. Energy-related interventions resulted in a 10% reduction in carbon footprint per case but would result in larger savings for the whole facility. Commonly implemented approaches, such as recycling surgical waste, resulted in less than a 5% reduction in greenhouse gases. Conclusions. To reduce the environmental emissions of surgeries, health care providers need to implement a combination of approaches, including minimizing materials, moving away from certain heat-trapping anesthetic gases, maximizing instrument reuse or single-use device reprocessing, and reducing off-hour energy use in the operating room. These strategies can reduce the carbon footprint of an average laparoscopic hysterectomy by up to 80%. Recycling alone does very little to reduce environmental footprint. Public Health Implications. Health care services are a major source of environmental emissions and reducing their carbon footprint would improve environmental and human health. Facilities seeking to reduce environmental footprint should take a comprehensive systems approach to find safe and effective interventions and should identify and address policy barriers to implementing more sustainable practices. PMID:29698098
Volatile organic compound sensing devices
Lancaster, G.D.; Moore, G.A.; Stone, M.L.; Reagen, W.K.
1995-08-29
Apparatus employing vapochromic materials in the form of inorganic double complex salts which change color reversibly when exposed to volatile organic compound (VOC) vapors is adapted for VOC vapor detection, VOC aqueous matrix detection, and selective VOC vapor detection. The basic VOC vapochromic sensor is incorporated in various devices such as a ground probe sensor, a wristband sensor, a periodic sampling monitor, a soil/water penetrometer, an evaporative purge sensor, and various vacuum-based sensors which are particularly adapted for reversible/reusable detection, remote detection, continuous monitoring, or rapid screening of environmental remediation and waste management sites. The vapochromic sensor is used in combination with various fiber optic arrangements to provide a calibrated qualitative and/or quantitative indication of the presence of VOCs. 15 figs.
Volatile organic compound sensing devices
Lancaster, Gregory D.; Moore, Glenn A.; Stone, Mark L.; Reagen, William K.
1995-01-01
Apparatus employing vapochromic materials in the form of inorganic double complex salts which change color reversibly when exposed to volatile organic compound (VOC) vapors is adapted for VOC vapor detection, VOC aqueous matrix detection, and selective VOC vapor detection. The basic VOC vapochromic sensor is incorporated in various devices such as a ground probe sensor, a wristband sensor, a periodic sampling monitor, a soil/water penetrometer, an evaporative purge sensor, and various vacuum-based sensors which are particularly adapted for reversible/reusable detection, remote detection, continuous monitoring, or rapid screening of environmental remediation and waste management sites. The vapochromic sensor is used in combination with various fiber optic arrangements to provide a calibrated qualitative and/or quantitative indication of the presence of VOCs.
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.
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.
Shin, Donghyeop; Zhu, Tong; Huang, Xuan; Gunawan, Oki; Blum, Volker; Mitzi, David B
2017-06-01
In recent years, Cu 2 ZnSn(S,Se) 4 (CZTSSe) materials have enabled important progress in associated thin-film photovoltaic (PV) technology, while avoiding scarce and/or toxic metals; however, cationic disorder and associated band tailing fundamentally limit device performance. Cu 2 BaSnS 4 (CBTS) has recently been proposed as a prospective alternative large bandgap (~2 eV), environmentally friendly PV material, with ~2% power conversion efficiency (PCE) already demonstrated in corresponding devices. In this study, a two-step process (i.e., precursor sputter deposition followed by successive sulfurization/selenization) yields high-quality nominally pinhole-free films with large (>1 µm) grains of selenium-incorporated (x = 3) Cu 2 BaSnS 4- x Se x (CBTSSe) for high-efficiency PV devices. By incorporating Se in the sulfide film, absorber layers with 1.55 eV bandgap, ideal for single-junction PV, have been achieved within the CBTSSe trigonal structural family. The abrupt transition in quantum efficiency data for wavelengths above the absorption edge, coupled with a strong sharp photoluminescence feature, confirms the relative absence of band tailing in CBTSSe compared to CZTSSe. For the first time, by combining bandgap tuning with an air-annealing step, a CBTSSe-based PV device with 5.2% PCE (total area 0.425 cm 2 ) is reported, >2.5× better than the previous champion pure sulfide device. These results suggest substantial promise for the emerging Se-rich Cu 2 BaSnS 4- x Se x family for high-efficiency and earth-abundant PV. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Multi-Directional Environmental Sensors
NASA Technical Reports Server (NTRS)
Manohara, Harish (Inventor); Del Castillo, Linda Y. (Inventor); Mojarradi, Mohammed M. (Inventor)
2016-01-01
Systems and methods in accordance with embodiments of the invention implement multi-directional environmental sensors. In one embodiment, a multi-directional environmental sensor includes: an inner conductive element that is substantially symmetrical about three orthogonal planes; an outer conductive element that is substantially symmetrical about three orthogonal planes; and a device that measures the electrical characteristics of the multi-directional environmental sensor, the device having a first terminal and a second terminal; where the inner conductive element is substantially enclosed within the outer conductive element; where the inner conductive element is electrically coupled to the first terminal of the device; and where the outer conductive element is electrically coupled to the second terminal of the device.
Lead-Free MA2CuCl(x)Br(4-x) Hybrid Perovskites.
Cortecchia, Daniele; Dewi, Herlina Arianita; Yin, Jun; Bruno, Annalisa; Chen, Shi; Baikie, Tom; Boix, Pablo P; Grätzel, Michael; Mhaisalkar, Subodh; Soci, Cesare; Mathews, Nripan
2016-02-01
Despite their extremely good performance in solar cells with efficiencies approaching 20% and the emerging application for light-emitting devices, organic-inorganic lead halide perovskites suffer from high content of toxic, polluting, and bioaccumulative Pb, which may eventually hamper their commercialization. Here, we present the synthesis of two-dimensional (2D) Cu-based hybrid perovskites and study their optoelectronic properties to investigate their potential application in solar cells and light-emitting devices, providing a new environmental-friendly alternative to Pb. The series (CH3NH3)2CuCl(x)Br(4-x) was studied in detail, with the role of Cl found to be essential for stabilization. By exploiting the additional Cu d-d transitions and appropriately tuning the Br/Cl ratio, which affects ligand-to-metal charge transfer transitions, the optical absorption in this series of compounds can be extended to the near-infrared for optimal spectral overlap with the solar irradiance. In situ formation of Cu(+) ions was found to be responsible for the green photoluminescence of this material set. Processing conditions for integrating Cu-based perovskites into photovoltaic device architectures, as well as the factors currently limiting photovoltaic performance, are discussed: among them, we identified the combination of low absorption coefficient and heavy mass of the holes as main limitations for the solar cell efficiency. To the best of our knowledge, this is the first demonstration of the potential of 2D copper perovskite as light harvesters and lays the foundation for further development of perovskite based on transition metals as alternative lead-free materials. Appropriate molecular design will be necessary to improve the material's properties and solar cell performance filling the gap with the state-of-the-art Pb-based perovskite devices.
Using SDI-12 with ST microelectronics MCU's
DOE Office of Scientific and Technical Information (OSTI.GOV)
Saari, Alexandra; Hinzey, Shawn Adrian; Frigo, Janette Rose
2015-09-03
ST Microelectronics microcontrollers and processors are readily available, capable and economical processors. Unfortunately they lack a broad user base like similar offerings from Texas Instrument, Atmel, or Microchip. All of these devices could be useful in economical devices for remote sensing applications used with environmental sensing. With the increased need for environmental studies, and limited budgets, flexibility in hardware is very important. To that end, and in an effort to increase open support of ST devices, I am sharing my teams' experience in interfacing a common environmental sensor communication protocol (SDI-12) with ST devices.
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.
Ionization-induced annealing of pre-existing defects in silicon carbide
Zhang, Yanwen; Sachan, Ritesh; Pakarinen, Olli H.; ...
2015-08-12
A long-standing objective in materials research is to find innovative ways to remove preexisting damage and heal fabrication defects or environmentally induced defects in materials. Silicon carbide (SiC) is a fascinating wide-band gap semiconductor for high-temperature, high-power, high-frequency applications. Its high corrosion and radiation resistance makes it a key refractory/structural material with great potential for extremely harsh radiation environments. Here we show that the energy transferred to the electron system of SiC by energetic ions via inelastic ionization processes results in a highly localized thermal spike that can effectively heal preexisting defects and restore the structural order. This work revealsmore » an innovative self-healing process using highly ionizing ions, and it describes a critical aspect to be considered in modeling SiC performance as either a functional or a structural material for device applications or high-radiation environments.« less
Radiation protection using Martian surface materials in human exploration of Mars
NASA Technical Reports Server (NTRS)
Kim, M. H.; Thibeault, S. A.; Wilson, J. W.; Heilbronn, L.; Kiefer, R. L.; Weakley, J. A.; Dueber, J. L.; Fogarty, T.; Wilkins, R.
2001-01-01
To develop materials for shielding astronauts from the hazards of GCR, natural Martian surface materials are considered for their potential as radiation shielding for manned Mars missions. The modified radiation fluences behind various kinds of Martian rocks and regolith are determined by solving the Boltzmann equation using NASA Langley's HZETRN code along with the 1977 Solar Minimum galactic cosmic ray environmental model. To develop structural shielding composite materials for Martian surface habitats, theoretical predictions of the shielding properties of Martian regolith/polyimide composites has been computed to assess their shielding effectiveness. Adding high-performance polymer binders to Martian regolith to enhance structural properties also enhances the shielding properties of these composites because of the added hydrogenous constituents. Heavy ion beam testing of regolith simulant/polyimide composites is planned to validate this prediction. Characterization and proton beam tests are performed to measure structural properties and to compare the shielding effects on microelectronic devices, respectively.
Understanding Fundamentals and Reaction Mechanisms of Electrode Materials for Na-Ion Batteries.
Yu, Linghui; Wang, Luyuan Paul; Liao, Hanbin; Wang, Jingxian; Feng, Zhenxing; Lev, Ovadia; Loo, Joachim S C; Sougrati, Moulay Tahar; Xu, Zhichuan J
2018-04-01
Development of efficient, affordable, and sustainable energy storage technologies has become an area of interest due to the worsening environmental issues and rising technological dependence on Li-ion batteries. Na-ion batteries (NIBs) have been receiving intensive research efforts during the last few years. Owing to their potentially low cost and relatively high energy density, NIBs are promising energy storage devices, especially for stationary applications. A fundamental understanding of electrode properties during electrochemical reactions is important for the development of low cost, high-energy density, and long shelf life NIBs. This Review aims to summarize and discuss reaction mechanisms of the major types of NIB electrode materials reported. By appreciating how the material works and the fundamental flaws it possesses, it is hoped that this Review will assist readers in coming up with innovative solutions for designing better materials for NIBs. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
2007-03-01
similar in structure to HMX. HMX is used to implode fissionable material in nuclear devices to achieve critical mass and as a component of plastic...extent of DTRA activities on WSMR and reduce the Department of Defense capability to control and eliminate weapons of mass destruction. The Final...safeguarding the United States and its allies from weapons of mass destruction (WMD). DTRA maintains a number of test beds and target types at White Sands
Towards sustainable and renewable systems for electrochemical energy storage.
Tarascon, Jean-Marie
2008-01-01
Renewable energy sources and electric automotive transportation are popular topics in our belated energy-conscious society, placing electrochemical energy management as one of the major technological developments for this new century. Besides efficiency, any new storage technologies will have to provide advantages in terms of cost and environmental footprint and thus rely on sustainable materials that can be processed at low temperature. To meet such challenges future devices will require inspiration from living organisms and rely on either bio-inspired or biomimetic approaches.
Polymer Dispersed Liquid Crystal Displays
NASA Astrophysics Data System (ADS)
Doane, J. William
The following sections are included: * INTRODUCTION AND HISTORICAL DEVELOPMENT * PDLC MATERIALS PREPARATION * Polymerization induced phase separation (PIPS) * Thermally induced phase separation (TIPS) * Solvent induced phase separation (SIPS) * Encapsulation (NCAP) * RESPONSE VOLTAGE * Dielectric and resistive effects * Radial configuration * Bipolar configuration * Other director configurations * RESPONSE TIME * DISPLAY CONTRAST * Light scattering and index matching * Incorporation of dyes * Contrast measurements * PDLC DISPLAY DEVICES AND INNOVATIONS * Reflective direct view displays * Large-scale, flexible displays * Switchable windows * Projection displays * High definition spatial light modulator * Haze-free PDLC shutters: wide angle view displays * ENVIRONMENTAL STABILITY * ACKNOWLEDGEMENTS * REFERENCES
Environmental fate and effect of biodegradable electro-spun scaffolds (biomaterial)-a case study.
Irizar, A; Amorim, M J B; Fuller, K P; Zeugolis, D I; Scott-Fordsmand, J J
2018-04-30
Poly-ε-caprolactone (PCL) based medical devices are increasingly produced and thus, their presence in the environment is likely to increase. The present study analysed the biodegradation of PCL electro-spun scaffolds (alone) and PCL electro-spun scaffolds coated with human recombinant (hR) collagen and Bovine Achilles tendon (BAT) collagen in sewage sludge and in soil. Additionally, an eco-toxicological test with the model organism Enchytraeus crypticus was performed to assess environmental hazard of the produced materials in soils. The electro-spun scaffolds were exposed to activated sludge and three different soils for various time periods (0-7-14-21-28-56-180 days); subsequently the degradation was determined by weight loss and microscopical analysis. Although no toxicity occurred in terms of Enchytraeus crypticus reproduction, our data indicate that biodegradation was dependent on the coating of the material and exposure condition. Further, only partial PCL decomposition was possible in sewage treatment plants. Collectively, these data indicate that electro-spun PCL scaffolds are transferred to amended soils.
The effects of maintaining temperature in annealing heat treatment for an FSWed 6061-T6 Al alloy.
Lee, Seung-Jun; Han, Min-Su; Kim, Seong-Jong
2013-08-01
The technological development of all kinds of lightweight transportation devices including vehicles, aircraft, ships, etc. has progressed markedly with the demand for energy saving and environmental protection. Aluminum alloy is in the spotlight as it is a suitable environmentally friendly material. However, deformation is a major problem during the welding process because aluminum alloy has a large thermal expansion coefficient. In addition, it is known that its corrosion resistance is excellent; nevertheless, in practice, considerable corrosion is generated and this is a major problem. To solve this problem, the friction stir welding (FSW) technology is applied extensively at various industrial fields as a new welding technique. This method involves a process in which materials are joined by frictional heat and physical force. Therefore, we evaluated improvements in mechanical properties and corrosion resistance through annealing heat treatment after FSW. The electrochemical experiment did not show a significant difference. However, the microstructure observation showed defectless, fine crystal particles, indicating excellent properties at 200-225°C.
High temperature electrical energy storage: advances, challenges, and frontiers.
Lin, Xinrong; Salari, Maryam; Arava, Leela Mohana Reddy; Ajayan, Pulickel M; Grinstaff, Mark W
2016-10-24
With the ongoing global effort to reduce greenhouse gas emission and dependence on oil, electrical energy storage (EES) devices such as Li-ion batteries and supercapacitors have become ubiquitous. Today, EES devices are entering the broader energy use arena and playing key roles in energy storage, transfer, and delivery within, for example, electric vehicles, large-scale grid storage, and sensors located in harsh environmental conditions, where performance at temperatures greater than 25 °C are required. The safety and high temperature durability are as critical or more so than other essential characteristics (e.g., capacity, energy and power density) for safe power output and long lifespan. Consequently, significant efforts are underway to design, fabricate, and evaluate EES devices along with characterization of device performance limitations such as thermal runaway and aging. Energy storage under extreme conditions is limited by the material properties of electrolytes, electrodes, and their synergetic interactions, and thus significant opportunities exist for chemical advancements and technological improvements. In this review, we present a comprehensive analysis of different applications associated with high temperature use (40-200 °C), recent advances in the development of reformulated or novel materials (including ionic liquids, solid polymer electrolytes, ceramics, and Si, LiFePO 4 , and LiMn 2 O 4 electrodes) with high thermal stability, and their demonstrative use in EES devices. Finally, we present a critical overview of the limitations of current high temperature systems and evaluate the future outlook of high temperature batteries with well-controlled safety, high energy/power density, and operation over a wide temperature range.
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.
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.
A single-layer permeation barrier for organic light-emitting displays
NASA Astrophysics Data System (ADS)
Mandlik, Prashant; Gartside, Jonathan; Han, Lin; Cheng, I.-Chun; Wagner, Sigurd; Silvernail, Jeff A.; Ma, Rui-Qing; Hack, Michael; Brown, Julie J.
2008-03-01
Films of a hybrid material with part-SiO2 part-silicone character are deposited as environmental barriers on bottom-emitting and on transparent organic light-emitting diodes. Devices coated with this barrier have lifetimes of up to ˜7500h when stored at 65°C and 85% relative humidity, by far exceeding the industrial requirement of 1000h. The intensity of the Si-O-Si absorption at the wavenumber of 1075cm-1, the wetting angle by water, and the indentation hardness support the interpretation of a homogeneous material with the properties of a SiO2-silicone hybrid. The films remain intact over 58600cycles of bending to ˜0.2% tensile strain.
A wall-free climate unit for acoustic levitators.
Schlegel, M C; Wenzel, K-J; Sarfraz, A; Panne, U; Emmerling, F
2012-05-01
Acoustic levitation represents the physical background of trapping a sample in a standing acoustic wave with no contact to the wave generating device. For the last three decades, sample holders based on this effect have been commonly used for contact free handling of samples coupled with a number of analytical techniques. In this study, a wall-free climate unit is presented, which allows the control of the environmental conditions of suspended samples. The insulation is based on a continuous cold/hot gas flow around the sample and thus does not require any additional isolation material. This provides a direct access to the levitated sample and circumvents any influence of the climate unit material to the running analyses.
Nanomaterials for renewable energy
Chen, Shimou; Li, Liang; Sun, Hanwen; ...
2015-05-19
With demand for sustainable energy, resource, and environment protection, new material technologies are constantly expanding during the last few couple of decades. An intensive attention has been given by the scientific communities. In particular, nanomaterials are increasingly playing an active role either by increasing the efficiency of the energy storage and conversion processes or by improving the device design and performance. This special issue presents recent research advances in various aspects of energy storage technologies, advanced batteries, fuel cells, solar cell, biofuels, and so on. Design and synthesis of novel materials have demonstrated great impact on the utilization of themore » sustainable energy, which need to solve the increasing shortage of resource and the issues of environmental pollution.« less
A wall-free climate unit for acoustic levitators
NASA Astrophysics Data System (ADS)
Schlegel, M. C.; Wenzel, K.-J.; Sarfraz, A.; Panne, U.; Emmerling, F.
2012-05-01
Acoustic levitation represents the physical background of trapping a sample in a standing acoustic wave with no contact to the wave generating device. For the last three decades, sample holders based on this effect have been commonly used for contact free handling of samples coupled with a number of analytical techniques. In this study, a wall-free climate unit is presented, which allows the control of the environmental conditions of suspended samples. The insulation is based on a continuous cold/hot gas flow around the sample and thus does not require any additional isolation material. This provides a direct access to the levitated sample and circumvents any influence of the climate unit material to the running analyses.
Nature-Inspired Structural Materials for Flexible Electronic Devices.
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.
Rapid determination of actinides in asphalt samples
Maxwell, Sherrod L.; Culligan, Brian K.; Hutchison, Jay B.
2014-01-12
A new rapid method for the determination of actinides in asphalt samples has been developed that can be used in emergency response situations or for routine analysis If a radiological dispersive device (RDD), Improvised Nuclear Device (IND) or a nuclear accident such as the accident at the Fukushima Nuclear Power Plant in March, 2011 occurs, there will be an urgent need for rapid analyses of many different environmental matrices, including asphalt materials, to support dose mitigation and environmental clean up. The new method for the determination of actinides in asphalt utilizes a rapid furnace step to destroy bitumen and organicsmore » present in the asphalt and sodium hydroxide fusion to digest the remaining sample. Sample preconcentration steps are used to collect the actinides and a new stacked TRU Resin + DGA Resin column method is employed to separate the actinide isotopes in the asphalt samples. The TRU Resin plus DGA Resin separation approach, which allows sequential separation of plutonium, uranium, americium and curium isotopes in asphalt samples, can be applied to soil samples as well.« less
Current status and future prospects of power generators using dielectric elastomers
NASA Astrophysics Data System (ADS)
Chiba, Seiki; Waki, Mikio; Kornbluh, Roy; Pelrine, Ron
2011-12-01
Electroactive polymer artificial muscle (EPAM), known collectively as dielectric elastomers in the literature, has been shown to offer unique capabilities as an actuator and is now being developed for a wide variety of generator applications. EPAM has several characteristics that make it potentially well suited for wave, water current, wind, human motion, and other environmental energy harvesting systems including a high energy density allowing for minimal EPAM material quantities, high energy conversion efficiency independent of frequency of operation and non-toxic and low-cost materials not susceptible to corrosion. Experiments have been performed on push-button and heel-mounted generator devices powered by human motion, ocean wave power harvesters mounted on buoys and water turbines. While the power output levels of such demonstration devices is small, the performance of these devices has supported the potential benefits of EPAM. For example, an electrical energy conversion efficiency of over 70% was achieved with small wave heights. The ability of EPAM to produce hydrogen fuel for energy storage was also demonstrated. Because the energy conversion principle of EPAM is capacitive in nature, the performance is largely independent of size and it should eventually be possible to scale up EPAM generators to the megawatt level to address a variety of electrical power needs.
Fei, Ruixiang; Faghaninia, Alireza; Soklaski, Ryan; Yan, Jia-An; Lo, Cynthia; Yang, Li
2014-11-12
Thermoelectric devices that utilize the Seebeck effect convert heat flow into electrical energy and are highly desirable for the development of portable, solid state, passively powered electronic systems. The conversion efficiencies of such devices are quantified by the dimensionless thermoelectric figure of merit (ZT), which is proportional to the ratio of a device's electrical conductance to its thermal conductance. In this paper, a recently fabricated two-dimensional (2D) semiconductor called phosphorene (monolayer black phosphorus) is assessed for its thermoelectric capabilities. First-principles and model calculations reveal not only that phosphorene possesses a spatially anisotropic electrical conductance, but that its lattice thermal conductance exhibits a pronounced spatial-anisotropy as well. The prominent electrical and thermal conducting directions are orthogonal to one another, enhancing the ratio of these conductances. As a result, ZT may reach the criterion for commercial deployment along the armchair direction of phosphorene at T = 500 K and is close to 1 even at room temperature given moderate doping (∼2 × 10(16) m(-2) or 2 × 10(12) cm(-2)). Ultimately, phosphorene hopefully stands out as an environmentally sound thermoelectric material with unprecedented qualities. Intrinsically, it is a mechanically flexible material that converts heat energy with high efficiency at low temperatures (∼300 K), one whose performance does not require any sophisticated engineering techniques.
NASA Astrophysics Data System (ADS)
Paul, Sujata
In the course of my PhD I have worked on a broad range of problems using simulations from first principles: from catalysis and chemical reactions at surfaces and on nanostructures, characterization of carbon-based systems and devices, and surface and interface physics. My research activities focused on the application of ab-initio electronic structure techniques to the theoretical study of important aspects of the physics and chemistry of materials for energy and environmental applications and nano-electronic devices. A common theme of my research is the computational study of chemical reactions of environmentally important molecules (CO, CO2) using high performance simulations. In particular, my principal aim was to design novel nano-structured functional catalytic surfaces and interfaces for environmentally relevant remediation and recycling reactions, with particular attention to the management of carbon dioxide. We have studied the carbon-mediated partial sequestration and selective oxidation of carbon monoxide (CO), both in the presence and absence of hydrogen, on graphitic edges. Using first-principles calculations we have studied several reactions of CO with carbon nanostructures, where the active sites can be regenerated by the deposition of carbon decomposed from the reactant (CO) to make the reactions self-sustained. Using statistical mechanics, we have also studied the conditions under which the conversion of CO to graphene and carbon dioxide is thermodynamically favorable, both in the presence and in the absence of hydrogen. These results are a first step toward the development of processes for the carbon-mediated partial sequestration and selective oxidation of CO in a hydrogen atmosphere. We have elucidated the atomic scale mechanisms of activation and reduction of carbon dioxide on specifically designed catalytic surfaces via the rational manipulation of the surface properties that can be achieved by combining transition metal thin films on oxide substrates. We have analyzed the mechanisms of the molecular reactions on the class of catalytic surfaces so designed in an effort to optimize materials parameters in the search of optimal catalytic materials. All these studies are likely to bring new perspectives and substantial advancement in the field of high-performance simulations in catalysis and the characterization of nanostructures for energy and environmental applications. Moving to novel materials for electronics applications, I have studied the structural and vibrational properties of mono and bi-layer graphene. I have characterized the lattice thermal conductivity of ideal monolayer and bi-layer graphene, demonstrating that their behavior is similar to that observed in graphite and indicating that the intra-layer coupling does not affect significantly the thermal conductance. I have also calculated the electron-phonon interaction in monolayer graphene and obtained electron scattering rates associated with all phonon modes and the intrinsic resistivity/mobility of monolayer graphene is estimated as a function of temperature. On another project, I have worked on ab initio molecular dynamic studies of novel Phase Change Materials (PCM) for memory and 3D-integration. We characterized high-temperature, sodium | nickel chloride, rechargeable batteries. These batteries are under consideration for hybrid drive systems in transportation applications. As part of our activities to improve performance and reliability of these batteries, we developed an engineering transport model of the component electrochemical cell. To support that model, we have proposed a reaction kinetics expression for the REDOX (reduction-oxidation) reaction at the porous positive electrode. We validate the kinetics expression with electrochemical measurements. A methodology based on the transistor body effect is used to estimate inversion oxide thicknesses (Tinv) in high-kappa/metal gate, undoped, ultra-thin body SOI FINFETs. The extracted Tinvs are compared to independent capacitance voltage (CV) measurements.
Materials International Space Station Experiment (MISSE): Overview, Accomplishments and Future Needs
NASA Technical Reports Server (NTRS)
deGroh, Kim K.; Jaworske, Donald A.; Pippin, Gary; Jenkins, Philip P.; Walters, Robert J.; Thibeault, Sheila A.; Palusinski, Iwona; Lorentzen, Justin R.
2014-01-01
Materials and devices used on the exterior of spacecraft in low Earth orbit (LEO) are subjected to environmental threats that can cause degradation in material properties, possibly threatening spacecraft mission success. These threats include: atomic oxygen (AO), ultraviolet and x-ray radiation, charged particle radiation, temperature extremes and thermal cycling, micrometeoroid and debris impacts, and contamination. Space environmental threats vary greatly based on spacecraft materials, thicknesses and stress levels, and the mission environment and duration. For more than a decade the Materials International Space Station Experiment (MISSE) has enabled the study of the long duration environmental durability of spacecraft materials in the LEO environment. The overall objective of MISSE is to test the stability and durability of materials and devices in the space environment in order to gain valuable knowledge on the performance of materials in space, as well as to enable lifetime predictions of new materials that may be used in future space flight. MISSE is a series of materials flight experiments, which are attached to the exterior of the International Space Station (ISS). Individual experiments were loaded onto suitcase-like trays, called Passive Experiment Containers (PECs). The PECs were transported to the ISS in the Space Shuttle cargo bay and attached to, and removed from, the ISS during extravehicular activities (EVAs). The PECs were retrieved after one or more years of space exposure and returned to Earth enabling post-flight experiment evaluation. MISSE is a multi-organization project with participants from the National Aeronautics and Space Administration (NASA), the Department of Defense (DoD), industry and academia. MISSE has provided a platform for environmental durability studies for thousands of samples and numerous devices, and it has produced many tangible impacts. Ten PECs (and one smaller tray) have been flown, representing MISSE 1 through MISSE 8, yielding long-duration space environmental performance and durability data that enable material validation, processing recertification and space qualification; improved predictions of materials and component lifetimes in space; model verification and development; and correlation factors between space-exposure and ground-facilities enabling more accurate in-space performance predictions based on ground-laboratory testing. A few of the many experiment results and observations, and their impacts, are provided. Those highlighted include examples on improved understanding of atomic oxygen scattering mechanisms, LEO coating durability results, and polymer erosion yields and their impacts on spacecraft design. The MISSE 2 Atomic Oxygen Scattering Chamber Experiment discovered that the peak flux of scattered AO was determined to be 45 deg from normal incidence, not the model predicted cosine dependence. In addition, the erosion yield (E(sub y)) of Kapton H for AO scattered off oxidized-Al is 22% of the E(sub y) of direct AO impingement. These results were used to help determine the degradation mechanism of a cesium iodide detector within the Hubble Space Telescope Cosmic Origins Spectrograph Experiment. The MISSE 6 Indium Tin Oxide (ITO) Degradation Experiment measured surface electrical resistance of ram and wake ITO coated samples. The data confirmed that ITO is a stable AO protective coating, and the results validated the durability of ITO conductive coatings for solar arrays for the Atmosphere-Space Transition 2 Explorer program. The MISSE 2, 6 and 7 Polymer Experiments have provided LEO AO Ey data on over 120 polymer and composites samples. The flight E(sub y) values were found to range from 3.05 x 10(exp -26) cu cm/atom for the AO resistant polymer CORIN to 9.14 x 10(exp -26) cu cm/atom for polyoxymethylene (POM). In addition, flying the same polymers on different missions has advanced the understanding of the AO E(sub y) dependency on solar exposure for polymers containing fluorine. The MISSE polymer results are highly requested and have impacted spacecraft design for WorldView-2 & -3, the Global Precipitation Measurement-Microwave Imager, and other spacecraft. The flight data has enabled the development of an Atomic Oxygen Erosion Predictive Tool that allows the erosion prediction of new and non-flown polymers. The data has also been used to develop a new NASA Technical Standards Handbook "Spacecraft Polymers Atomic Oxygen Durability Handbook." Many intangible benefits have also been derived from MISSE. For example, over 40 students have collaborated on Glenn's MISSE experiments, which have resulted in greater than $80K in student scholarships and awards in national and international science fairs. Students have also given presentations and won poster competition awards at international space conferences.
Dielectrophoretic separation of Bacillus subtilis spores from environmental diesel particles.
Fatoyinbo, Henry O; Hughes, Michael P; Martin, Stacey P; Pashby, Paul; Labeed, Fatima H
2007-01-01
Isolation of pathogenic bacteria from non-biological material of similar size is a vital sample preparation step in the identification of such organisms, particularly in the context of detecting bio-terrorist attacks. However, many detection methods are impeded by particulate contamination from the environment such as those from engine exhausts. In this paper we use dielectrophoresis--the induced motion of particles in non-uniform fields--to successfully remove over 99% of diesel particulates acquired from environmental samples, whilst letting bacterial spores of B. subtilis pass through the chamber largely unimpeded. We believe that such a device has tremendous potential as a precursor to a range of detection methods, improving the signal-to-noise ratio and ultimately improving detection rates.
Removal of Organic Pollutants from Water Using Superwetting Materials.
Li, Lingxiao; Zhang, Junping; Wang, Aiqin
2018-02-01
The frequent occurrence of water pollution accidents and the leakage of organic pollutants have caused severe environmental and ecological crisis. It is thus highly imperative to find efficient materials to solve the problem. Inspired by the lotus leaf, superwetting materials are receiving increasing attention in the field of removal of organic pollutants from water. Various superwetting materials have been successfully generated and integrated into devices for removal of organic pollutants from water. On the basis of our previous work in the field, we summarized in this account the progress of removal of (1) floating and underwater insoluble, (2) emulsified insoluble, and (3) both insoluble and soluble organic pollutants from water using superwetting materials including superhydrophobic & superoleophilic materials, superhydrophilic & underwater superoleophobic materials, and materials with controllable wettability. The superwetting materials are in the forms of 2D porous materials, 3D porous materials and particles, etc. Finally, the current state and future challenges in this field are discussed. We hope this account could shed light on the design of novel superwetting materials for efficient removal of organic pollutants from water. © 2018 The Chemical Society of Japan & Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
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...
A next-generation in-situ nanoprobe beamline for the Advanced Photon Source
NASA Astrophysics Data System (ADS)
Maser, Jörg; Lai, Barry; Buonassisi, Tonio; Cai, Zhonghou; Chen, Si; Finney, Lydia; Gleber, Sophie-Charlotte; Harder, Ross; Jacobsen, Chris; Liu, Wenjun; Murray, Conal; Preissner, Curt; Roehrig, Chris; Rose, Volker; Shu, Deming; Vine, David; Vogt, Stefan
2013-09-01
The Advanced Photon Source is currently developing a suite of new hard x-ray beamlines, aimed primarily at the study of materials and devices under real conditions. One of the flagship beamlines of the APS Upgrade is the In-Situ Nanoprobe beamline (ISN beamline), which will provide in-situ and operando characterization of advanced energy materials and devices under change of temperature and gases, under applied fields, in 3D. The ISN beamline is designed to deliver spatially coherent x-rays with photon energies between 4 keV and 30 keV to the ISN instrument. As an x-ray source, a revolver-type undulator with two interchangeable magnetic structures, optimized to provide high brilliance throughout the range of photon energies of 4 keV - 30 keV, will be used. The ISN instrument will provide a smallest hard x-ray spot of 20 nm using diffractive optics, with sensitivity to sub-10 nm sample structures using coherent diffraction. Using nanofocusing mirrors in Kirkpatrick-Baez geometry, the ISN will also provide a focus of 50 nm with a flux of 8·1011 Photons/s at a photon energy of 10 keV, several orders of magnitude larger than what is currently available. This will allow imaging of trace amounts of most elements in the periodic table, with a sensitivity to well below 100 atoms for most metals in thin samples. It will also enable nanospectroscopic studies of the chemical state of most materials relevant to energy science. The ISN beamline will be primarily used to study inorganic and organic photovoltaic systems, advanced batteries and fuel cells, nanoelectronics devices, and materials and systems diesigned to reduce the environmental impact of combustion.
Dragone, Roberto; Grasso, Gerardo; Muccini, Michele; Toffanin, Stefano
2017-01-01
This mini-review covers the newly developed biosensoristic and chemosensoristic devices described in recent literature for detection of contaminants in both environmental and food real matrices. Current needs in environmental and food surveillance of contaminants require new simplified, sensitive systems, which are portable and allow for rapid and on-site monitoring and diagnostics. Here, we focus on optical and electrochemical bio/chemosensoristic devices as promising tools with interesting analytical features that can be potentially exploited for innovative on-site and real-time applications for diagnostics and monitoring of environmental and food matrices (e.g., agricultural waters and milk). In near future, suitably developed and implemented bio/chemosensoristic devices will be a new and modern technological solution for the identification of new quality and safety marker indexes as well as for a more proper and complete characterization of abovementioned environmental and food matrices. Integrated bio/chemosensoristic devices can also allow an “holistic approach” that may prove to be more suitable for diagnostics of environmental and food real matrices, where the copresence of more bioactive substances is frequent. Therefore, this approach can be focused on the determination of net effect (mixture effect) of bioactive substances present in real matrices. PMID:28529937
Dragone, Roberto; Grasso, Gerardo; Muccini, Michele; Toffanin, Stefano
2017-01-01
This mini-review covers the newly developed biosensoristic and chemosensoristic devices described in recent literature for detection of contaminants in both environmental and food real matrices. Current needs in environmental and food surveillance of contaminants require new simplified, sensitive systems, which are portable and allow for rapid and on-site monitoring and diagnostics. Here, we focus on optical and electrochemical bio/chemosensoristic devices as promising tools with interesting analytical features that can be potentially exploited for innovative on-site and real-time applications for diagnostics and monitoring of environmental and food matrices (e.g., agricultural waters and milk). In near future, suitably developed and implemented bio/chemosensoristic devices will be a new and modern technological solution for the identification of new quality and safety marker indexes as well as for a more proper and complete characterization of abovementioned environmental and food matrices. Integrated bio/chemosensoristic devices can also allow an "holistic approach" that may prove to be more suitable for diagnostics of environmental and food real matrices, where the copresence of more bioactive substances is frequent. Therefore, this approach can be focused on the determination of net effect (mixture effect) of bioactive substances present in real matrices.
NASA Astrophysics Data System (ADS)
Zhang, Xuetao; Zhou, Jinyuan; Dou, Wei; Wang, Junya; Mu, Xuemei; Zhang, Yue; Abas, Asim; Su, Qing; Lan, Wei; Xie, Erqing; Zhang, Chuanfang (John)
2018-04-01
The fast growing of portable electronics has greatly stimulated the development of energy storage materials, such as transition metal oxides (TMOs). However, TMOs usually involve harsh synthesis conditions, such as high temperature. Here we take advantage of the metastable nature of Cu(OH)2 and grow CuO nanoblades (NBs) on Cu foam under the electric field at room temperature. The electrochemical polarization accelerates the dissolution of Cu(OH)2 nanorods, guides the deposition of the as-dissolved Cu(OH)42- species and eventually leads to the phase transformation of CuO NBs. The unique materials architecture render the vertically-aligned CuO NBs with enhanced electronic and ionic diffusion kinetics, high charge storage (∼779 mC cm-2 at 1 mA cm-2), excellent rate capability and long-term cycling performances. Further matching with activated carbon electrode results in high-performance hybrid device, which displays a wide voltage window (1.7 V) in aqueous electrolyte, high energy density (0.17 mWh cm-2) and power density (34 mW cm-2) coupled with long lifetime, surpassing the best CuO based device known. The hybrid device can be randomly connected and power several light-emitting diodes. Importantly, such an electrochemical restructuring approach is cost-effective, environmentally green and universal, and can be extended to synthesize other metastable hydroxides to in-situ grow corresponding oxides.
Film bulk acoustic resonators (FBARs) as biosensors: A review.
Zhang, Yi; Luo, Jikui; Flewitt, Andrew J; Cai, Zhiqiang; Zhao, Xiubo
2018-09-30
Biosensors play important roles in different applications such as medical diagnostics, environmental monitoring, food safety, and the study of biomolecular interactions. Highly sensitive, label-free and disposable biosensors are particularly desired for many clinical applications. In the past decade, film bulk acoustic resonators (FBARs) have been developed as biosensors because of their high resonant frequency and small base mass (hence greater sensitivity), lower cost, label-free capability and small size. This paper reviews the piezoelectric materials used for FBARs, the optimisation of device structures, and their applications as biosensors in a wide range of biological applications such as the detection of antigens, DNAs and small biomolecules. Their integration with microfluidic devices and high-throughput detection are also discussed. Copyright © 2018 Elsevier B.V. All rights reserved.
Encapsulation methods for organic electrical devices
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.
ERIC Educational Resources Information Center
Schneiderman, Helen, Ed.
1994-01-01
Environmental control units, or ECUs, are devices or systems which allow for alternate access to electronic or electrical devices and those objects, like draperies and doors, which may be adapted for use with electricity. Such devices offer the person with a mobility limitation the opportunity to control his or her environment, thus enhancing the…
21 CFR 890.3725 - Powered environmental control system.
Code of Federal Regulations, 2014 CFR
2014-04-01
... 21 Food and Drugs 8 2014-04-01 2014-04-01 false Powered environmental control system. 890.3725 Section 890.3725 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3725 Powered...
21 CFR 890.3725 - Powered environmental control system.
Code of Federal Regulations, 2010 CFR
2010-04-01
... 21 Food and Drugs 8 2010-04-01 2010-04-01 false Powered environmental control system. 890.3725 Section 890.3725 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3725 Powered...
21 CFR 890.3725 - Powered environmental control system.
Code of Federal Regulations, 2011 CFR
2011-04-01
... 21 Food and Drugs 8 2011-04-01 2011-04-01 false Powered environmental control system. 890.3725 Section 890.3725 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3725 Powered...
21 CFR 890.3725 - Powered environmental control system.
Code of Federal Regulations, 2013 CFR
2013-04-01
... 21 Food and Drugs 8 2013-04-01 2013-04-01 false Powered environmental control system. 890.3725 Section 890.3725 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3725 Powered...
21 CFR 890.3725 - Powered environmental control system.
Code of Federal Regulations, 2012 CFR
2012-04-01
... 21 Food and Drugs 8 2012-04-01 2012-04-01 false Powered environmental control system. 890.3725 Section 890.3725 Food and Drugs FOOD AND DRUG ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES PHYSICAL MEDICINE DEVICES Physical Medicine Prosthetic Devices § 890.3725 Powered...
Morera, Serni; Corominas, Lluís; Rigola, Miquel; Poch, Manel; Comas, Joaquim
2017-10-01
The aim of this work is to quantify the relative contribution to the overall environmental impact of the construction phase compared to the operational phase for a large conventional activated sludge wastewater treatment plant (WWTP). To estimate these environmental impacts, a systematic procedure was designed to obtain the detailed Life Cycle Inventories (LCI) for civil works and equipment, taking as starting point the construction project budget and the list of equipment installed at the Girona WWTP, which are the most reliable information sources of materials and resources used during the construction phase. A detailed inventory is conducted by including 45 materials for civil works and 1,240 devices for the equipment. For most of the impact categories and different life spans of the WWTP, the contribution of the construction phase to the overall burden is higher than 5% and, especially for metal depletion, the impact of construction reaches 63%. When comparing to the WWTP inventories available in Ecoinvent the share of construction obtained in this work is about 3 times smaller for climate change and twice higher for metal depletion. Concrete and reinforcing steel are the materials with the highest contribution to the civil works phase and motors, pumps and mobile and transport equipment are also key equipment to consider during life cycle inventories of WWTPs. Additional robust inventories for similar WWTP can leverage this work by applying the factors (kg of materials and energy per m 3 of treated water) and guidance provided. Copyright © 2017 Elsevier Ltd. 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.
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.
NASA Astrophysics Data System (ADS)
Huang, Chieh-Szu; Chang, Ming-Chuan; Huang, Cheng-Liang; Lin, Shih-kang
2016-12-01
Thin-film electroluminescent devices are promising solid-state lighting devices. Red light-emitting phosphor is the key component to be integrated with the well-established blue light-emitting diode chips for stimulating natural sunlight. However, environmentally hazardous rare-earth (RE) dopants, e.g. Eu2+ and Ce2+, are commonly used for red-emitting phosphors. Mg2TiO4 inverse spinel has been reported as a promising matrix material for "RE-free" red light luminescent material. In this paper, Mg2TiO4 inverse spinel is investigated using both experimental and theoretical approaches. The Mg2TiO4 thin films were deposited on Si (100) substrates using either spin-coating with the sol-gel process, or radio frequency sputtering, and annealed at various temperatures ranging from 600°C to 900°C. The crystallinity, microstructures, and photoluminescent properties of the Mg2TiO4 thin films were characterized. In addition, the atomistic model of the Mg2TiO4 inverse spinel was constructed, and the electronic band structure of Mg2TiO4 was calculated based on density functional theory. Essential physical and optoelectronic properties of the Mg2TiO4 luminance material as well as its optimal thin-film processing conditions were comprehensively reported.
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.
Non- contacting capacitive diagnostic device
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.
Photonics and optoelectronics of two-dimensional materials beyond graphene.
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.
Koschinsky, Andrea; Heinrich, Luise; Boehnke, Klaus; Cohrs, J Christopher; Markus, Till; Shani, Maor; Singh, Pradeep; Stegen, Karen Smith; Werner, Welf
2018-06-19
Deep-sea mining refers to the retrieval of marine mineral resources such as manganese nodules, ferromanganese crusts and seafloor massive sulfide deposits, which contain a variety of metals that serve as crucial raw materials for a range of applications, from electronic devices to renewable energy technologies to construction materials. With the intent of decreasing dependence on imports, supporting the economy and potentially even overcoming the environmental problems related to conventional terrestrial mining, a number of public and private institutions have re-discovered their interest in exploring the prospects of deep-sea mining, which had been deemed economically and technically unfeasible in the early 1980 s. To date, many national and international research projects are grappling to understand the economic environmental, social and legal implications of potential commercial deep-sea mining operations: a challenging endeavor due to the complexity of direct impacts and spill-over effects. In this paper, we present a comprehensive overview of the current state of knowledge in the aforementioned fields as well as a comparison of the impacts associated with conventional terrestrial mining. Furthermore, we identify knowledge gaps that should be urgently addressed to ensure that the world at large benefits from safe, efficient and environmentally-sound mining procedures. We conclude by highlighting the need for interdisciplinary research and international cooperation. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.
Sample processing approach for detection of ricin in surface samples.
Kane, Staci; Shah, Sanjiv; Erler, Anne Marie; Alfaro, Teneile
2017-12-01
With several ricin contamination incidents reported over the past decade, rapid and accurate methods are needed for environmental sample analysis, especially after decontamination. A sample processing method was developed for common surface sampling devices to improve the limit of detection and avoid false negative/positive results for ricin analysis. Potential assay interferents from the sample matrix (bleach residue, sample material, wetting buffer), including reference dust, were tested using a Time-Resolved Fluorescence (TRF) immunoassay. Test results suggested that the sample matrix did not cause the elevated background fluorescence sometimes observed when analyzing post-bleach decontamination samples from ricin incidents. Furthermore, sample particulates (80mg/mL Arizona Test Dust) did not enhance background fluorescence or interfere with ricin detection by TRF. These results suggested that high background fluorescence in this immunoassay could be due to labeled antibody quality and/or quantity issues. Centrifugal ultrafiltration devices were evaluated for ricin concentration as a part of sample processing. Up to 30-fold concentration of ricin was observed by the devices, which serve to remove soluble interferents and could function as the front-end sample processing step to other ricin analytical methods. The procedure has the potential to be used with a broader range of environmental sample types and with other potential interferences and to be followed by other ricin analytical methods, although additional verification studies would be required. Published by Elsevier B.V.
Hollow-Fiber Membrane Chamber as a Device for In Situ Environmental Cultivation▿
Aoi, Yoshiteru; Kinoshita, Tomoyuki; Hata, Toru; Ohta, Hiroaki; Obokata, Haruko; Tsuneda, Satoshi
2009-01-01
A hollow-fiber membrane chamber (HFMC) was developed as an in situ cultivation device for environmental microorganisms. The HFMC system consists of 48 to 96 pieces of porous hollow-fiber membrane connected with injectors. The system allows rapid exchange of chemical compounds, thereby simulating a natural environment. Comparative analysis through the cultivation of three types of environmental samples was performed using this newly designed device and a conventional agar-based petri dish. The results show that the ratios of novel phylotypes in isolates, species-level diversities, and cultivabilities in HFMC-based cultivation are higher than those in an agar-based petri dish for all three samples, suggesting that the new in situ cultivation device is effective for cultivation of various environmental microorganisms. PMID:19329655
Sandetskaya, Natalia; Allelein, Susann; Kuhlmeier, Dirk
2013-12-01
A combination of Micro-Electro-Mechanical Systems and nanoscale structures allows for the creation of novel miniaturized devices, which broaden the boundaries of the diagnostic approaches. Some materials possess unique properties at the nanolevel, which are different from those in bulk materials. In the last few years these properties became a focus of interest for many researchers, as well as methods of production, design and operation of the nanoobjects. Intensive research and development work resulted in numerous inventions exploiting nanotechnology in miniaturized systems. Modern technical and laboratory equipment allows for the precise control of such devices, making them suitable for sensitive and accurate detection of the analytes. The current review highlights recent patents in the field of nanotechnology in microdevices, applicable for medical, environmental or food analysis. The paper covers the structural and functional basis of such systems and describes specific embodiments in three principal branches: application of nanoparticles, nanofluidics, and nanosensors in the miniaturized systems for advanced analytics and diagnostics. This overview is an update of an earlier review article.
Yang, Bin; Dyck, Ondrej K.; Univ. of Tennessee, Knoxville, TN; ...
2016-11-04
The chemical stability of organometallic halide perovskites is a major barrier facing their application in the fast rising field of next generation photovoltaics. These materials were shown to undergo degradation due to the influence of heat or moisture, significantly limiting the lifetime of associated devices. To overcome this stability issue, a fundamental understanding of degradation mechanisms is of foremost importance. Here, high resolution in situ transmission electron microscopy and electron energy loss spectroscopy elemental mapping were applied to probe morphological and structural changes in perovskite films during controlled environmental exposure treatments. Both moisture and oxygen in ambient air are revealedmore » to facilitate degradation in CH 3NH 3PbI 3 perovskites through decomposition and oxidation pathways, respectively. In addition, even in moisture- and oxygen-free environment evident degradation could be induced by heating at the solar cell s real-field operating temperature and the degradation was found to originate from defect sites. These findings provide fundamental insight to prevent degradation of perovskite materials and associated devices for realistic applications.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Yang, Bin; Dyck, Ondrej K.; Univ. of Tennessee, Knoxville, TN
The chemical stability of organometallic halide perovskites is a major barrier facing their application in the fast rising field of next generation photovoltaics. These materials were shown to undergo degradation due to the influence of heat or moisture, significantly limiting the lifetime of associated devices. To overcome this stability issue, a fundamental understanding of degradation mechanisms is of foremost importance. Here, high resolution in situ transmission electron microscopy and electron energy loss spectroscopy elemental mapping were applied to probe morphological and structural changes in perovskite films during controlled environmental exposure treatments. Both moisture and oxygen in ambient air are revealedmore » to facilitate degradation in CH 3NH 3PbI 3 perovskites through decomposition and oxidation pathways, respectively. In addition, even in moisture- and oxygen-free environment evident degradation could be induced by heating at the solar cell s real-field operating temperature and the degradation was found to originate from defect sites. These findings provide fundamental insight to prevent degradation of perovskite materials and associated devices for realistic applications.« less
Power SEMICONDUCTORS—STATE of Art and Future Trends
NASA Astrophysics Data System (ADS)
Benda, Vitezslav
2011-06-01
The importance of effective energy conversion control, including power generation from renewable and environmentally clean energy sources, increases due to rising energy demand. Power electronic systems for controlling and converting electrical energy have become the workhorse of modern society in many applications, both in industry and at home. Power electronics plays a very important role in traction and can be considered as brawns of robotics and automated manufacturing systems. Power semiconductor devices are the key electronic components used in power electronic systems. Advances in power semiconductor technology have improved the efficiency, size, weight and cost of power electronic systems. At present, IGCTs, IGBTs, and MOSFETs represent modern switching devices. Power integrated circuits (PIC) have been developed for the use of power converters for portable, automotive and aerospace applications. For advanced applications, new materials (SiC and GaN) have been introduced. This paper reviews the state of these devices and elaborates on their potentials in terms of higher voltages, higher power density, and better switching performance.
Kanemitsu, Keiji; Imasaka, Takayuki; Ishikawa, Shiho; Kunishima, Hiroyuki; Harigae, Hideo; Ueno, Kumi; Takemura, Hiromu; Hirayama, Yoshihiro; Kaku, Mitsuo
2005-05-01
To compare the efficacies of ethylene oxide gas (EOG), hydrogen peroxide gas plasma (PLASMA), and low-temperature steam formaldehyde (LTSF) sterilization methods. The efficacies of EOG, PLASMA, and LTSF sterilization were tested using metal and plastic plates, common medical instruments, and three process challenge devices with narrow lumens. All items were contaminated with Bacillus stearothermophilus spores or used a standard biological indicator. EOG and LTSF demonstrated effective killing of B. stearothermophilus spores, with or without serum, on plates, on instruments, and in process challenge devices. PLASMA failed to adequately sterilize materials on multiple trials in several experiments, including two of three plates, two of three instruments, and all process challenge devices. Our results suggest that PLASMA sterilization may be unsuccessful under certain conditions, particularly when used for items with complex shapes and narrow lumens. Alternatively, LTSF sterilization demonstrates excellent efficacy and is comparable to EOG sterilization. LTSF could potentially act as a substitute if EOG becomes unavailable due to environmental concerns.
Quantitative electrochemical metalloimmunoassay for TFF3 in urine using a paper analytical device.
DeGregory, Paul R; Tsai, Yi-Ju; Scida, Karen; Richards, Ian; Crooks, Richard M
2016-03-07
We report a paper-based assay platform for the detection of the kidney disease marker Trefoil Factor 3 (TFF3) in human urine. The sensor is based on a quantitative metalloimmunoassay that can determine TFF3 concentrations via electrochemical detection of environmentally stable silver nanoparticle (AgNP) labels attached to magnetic microbeads via a TFF3 immunosandwich. The paper electroanalytical device incorporates two preconcentration steps that make it possible to detect concentrations of TFF3 in human urine at the low end of the target TFF3 concentration range (0.03-7.0 μg mL(-1)). Importantly, the paper device provides a level of accuracy for TFF3 determination in human urine equivalent to that of a commercial kit. The paper sensor has a dynamic range of ∼2.5 orders of magnitude, only requires a simple, one-step incubation protocol, and is fast, requiring only 10 min to complete. The cost of the materials at the prototypic laboratory scale, excluding reagents, is just US$0.42.
Organic electrophosphorescence device having interfacial layers
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.
NASA Astrophysics Data System (ADS)
Onogaki, Hitoshi; Yokoyama, Shuichi
The temperature control of the environmental examination device has loss of the energy consumption to cool it while warming it. This paper proposed a tempareture control system method with energy saving for the enviromental examination device without using cooling in consideration of temperature characteristics.
Science and Emerging Technology of 2D Atomic Layered Materials and Devices
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
Encapsulation methods and dielectric layers for organic electrical devices
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.
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
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.
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...
Nanostructured conjugated polymers in chemical sensors: synthesis, properties and applications.
Correa, D S; Medeiros, E S; Oliveira, J E; Paterno, L G; Mattoso, Luiz C
2014-09-01
Conjugated polymers are organic materials endowed with a π-electron conjugation along the polymer backbone that present appealing electrical and optical properties for technological applications. By using conjugated polymeric materials in the nanoscale, such properties can be further enhanced. In addition, the use of nanostructured materials makes possible miniaturize devices at the micro/nano scale. The applications of conjugated nanostructured polymers include sensors, actuators, flexible displays, discrete electronic devices, and smart fabric, to name a few. In particular, the use of conjugated polymers in chemical and biological sensors is made feasible owning to their sensitivity to the physicochemical conditions of its surrounding environment, such as chemical composition, pH, dielectric constant, humidity or even temperature. Subtle changes in these conditions bring about variations on the electrical (resistivity and capacitance), optical (absorptivity, luminescence, etc.), and mechanical properties of the conjugated polymer, which can be precisely measured by different experimental methods and ultimately associated with a specific analyte and its concentration. The present review article highlights the main features of conjugated polymers that make them suitable for chemical sensors. An especial emphasis is given to nanostructured sensors systems, which present high sensitivity and selectivity, and find application in beverage and food quality control, pharmaceutical industries, medical diagnosis, environmental monitoring, and homeland security, and other applications as discussed throughout this review.
NASA Astrophysics Data System (ADS)
Valero Conzuelo, Laura Luz
Over the past decade scientific research has been looking for new biomimetic materials able to imitate human organs behaviour, in such a way that is possible to apply them on different technologies: low cost ones, scalable ones, low energy consumption ones and on those with high potentialities in areas such as health, robotics, artificial nerves and muscles, among others. Most of the studied materials mimic the extracellular matrix (ECM) of living cells and its physical functions. Now, and for the first time, conducting polymers, and other electroactive materials exchange ions and water through electrochemical reactions: the material becomes a dense electroactive gel. The content of mentioned gel and the reactions happening in it mimic, by the first time in the history of science, the composition (in its simplest expression) and reactions taking place in the reactive intracellular matrix of the functional cells of living beings. During the chemical reactions (oxidation or reduction) the gel relative composition (polymer-ion-water) shifts, in a reversible way, by several orders of magnitude. Along with it several composition-dependent properties of the material change simultaneously. The reversible variation of the material volume driven by the reactions mimics the natural muscles behaviour: artificial polymeric muscles, or polymeric electrochemical actuators, based on this property are being developed. With the material composition the consumed energy change as a function thermal, chemical or mechanical conditions. This fact is used for the development of sensors and biosensors. The material volume and the material potential shift, simultaneously, during the reaction. Here the possibility to develop dual sensing-actuators is explored: two elements working concurrently in the same, physically uniform, device mimicking haptic muscles. In this thesis the electrochemical synthesis of thick polypyrrole/DBS films is described. The electrochemical behaviour of the polymer film, used as a self-supported electrode, is characterized assuming the exchange of cations during its oxidation/reduction. For the electrochemical characterization of biomimetic films of polypyrrole/DBS, different electrochemical techniques are used and under different experimental conditions with the view to understanding the sensing potentialities of the material reactions. The study and electrochemical characterization of the motion of pPy/DBS//tape bilayer bending actuators corroborates that the reaction is driven by the expulsion of cations from the conducting polymer to the electrolyte during oxidation and its entrance during reduction, in the full potential range studied. The actuator is a faradaic device controlled by the electrochemical reaction driving the movement: the rate of the angular movement is a linear function (easy control of the velocity) of the applied current and the described angle by the displacement is a linear function of the consumed charge (it also provides another easy control of the displacement). The evolution of the muscle potential and that of the consumed electrical energy during the reaction senses the energetic working conditions: chemical energy (electrolyte concentration), thermal energy (working temperature) or electric energy (applied current). The polymeric motor senses, while working, environmental conditions. The sensing calibration curves were attained for the different sensors. They have been constructed and characterized triple-layer artificial muscles pPy/DBS//Tape//pPy/DBS, corroborating again the exchange of cations during the reaction, the faradic nature of the device and the ability of the device to sense, while moving, its environmental working conditions mimicking natural haptic muscles. The actuator (current and charge) and sensing (muscle potential and involved energy) signals are simultaneously present in only two connecting wires, mimicking brain-muscle intercommunication. The study of polymeric materials with cationic and/or ionic exchange opens the possibility of working in a future, using also anion-exchange materials, to develop new soft, wet, biomimetic and multifunctional tools and robots. Ionic, chemical, thermal and mechanical signals can be transformed into electrical ones and the involved information is transported using just two wires, simplifying in that way their connection to computers: the design of devices and robots having them heralds a more efficient technology.
NASA Astrophysics Data System (ADS)
Lam, Carl
Due to technology proliferation, the environmental burden attributed to the production, use, and disposal of hazardous materials in electronics have become a worldwide concern. The major theme of this dissertation is to develop and apply hazardous materials assessment tools to systematically guide pollution prevention opportunities in the context of electronic product design, manufacturing and end-of-life waste management. To this extent, a comprehensive review is first provided on describing hazard traits and current assessment methods to evaluate hazardous materials. As a case study at the manufacturing level, life cycle impact assessment (LCIA)-based and risk-based screening methods are used to quantify chemical and geographic environmental impacts in the U.S. printed wiring board (PWB) industry. Results from this industrial assessment clarify priority waste streams and States to most effectively mitigate impact. With further knowledge of PWB manufacturing processes, select alternative chemical processes (e.g., spent copper etchant recovery) and material options (e.g., lead-free etch resist) are discussed. In addition, an investigation on technology transition effects for computers and televisions in the U.S. market is performed by linking dynamic materials flow and environmental assessment models. The analysis forecasts quantities of waste units generated and maps shifts in environmental impact potentials associated with metal composition changes due to product substitutions. This insight is important to understand the timing and waste quantities expected and the emerging toxic elements needed to be addressed as a consequence of technology transition. At the product level, electronic utility meter devices are evaluated to eliminate hazardous materials within product components. Development and application of a component Toxic Potential Indicator (TPI) assessment methodology highlights priority components requiring material alternatives. Alternative recommendations are provided and substitute materials such as aluminum alloys for stainless steel and high-density polyethylene for polyvinyl chloride and acrylonitrile-based polymers show promise to meet toxicity reduction, cost, and material functionality requirements. Furthermore, the TPI method, an European Union focused screening tool, is customized to reflect regulated U.S. toxicity parameters. Results show that, although it is possible to adopt U.S. parameters into the TPI method, harmonization of toxicity regulation and standards in various nations and regions is necessary to eliminate inconsistencies during hazard screening of substances used globally. As a whole, the present work helps to assimilate material hazard assessment methods into the larger framework of design for environment strategies so toxics use reduction could be achieved for the development and management of electronics and other consumer goods.
Device for detection and identification of carbon- and nitrogen-containing materials
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.
Simultaneous measurement of triboelectrification and triboluminescence of crystalline materials
NASA Astrophysics Data System (ADS)
Collins, Adam L.; Camara, Carlos G.; Van Cleve, Eli; Putterman, Seth J.
2018-01-01
Triboelectrification has been studied for over 2500 years, yet there is still a lack of fundamental understanding as to its origin. Given its utility in areas such as xerography, powder spray painting, and energy harvesting, many devices have been made to investigate triboelectrification at many length-scales, though few seek to additionally make use of triboluminescence: the emission of electromagnetic radiation immediately following a charge separation event. As devices for measuring triboelectrification became smaller and smaller, now measuring down to the atomic scale with atomic force microscope based designs, an appreciation for the collective and multi-scale nature of triboelectrification has perhaps abated. Consider that the energy required to move a unit charge is very large compared to a van der Waals interaction, yet peeling Scotch tape (whose adhesion is derived from van der Waals forces) can provide strong enough energy-focusing to generate X-ray emission. This paper presents a device to press approximately cm-sized materials together in a vacuum, with in situ alignment. Residual surface charge, force, and position and X-ray, visible light, and RF emission are measured for single crystal samples. Charge is therefore tracked throughout the charging and discharging processes, resulting in a more complete picture of triboelectrification, with controllable and measurable environmental influence. Macroscale charging is directly measured, whilst triboluminescence, originating in atomic-scale processes, probes the microscale. The apparatus was built with the goal of obtaining an ab initio-level explanation of triboelectrification for well-defined materials, at the micro- and macro-scale, which has eluded scientists for millennia.
Processes for multi-layer devices utilizing layer transfer
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.
Industrial waste materials and by-products as thermal energy storage (TES) materials: A review
NASA Astrophysics Data System (ADS)
Gutierrez, Andrea; Miró, Laia; Gil, Antoni; Rodríguez-Aseguinolaza, Javier; Barreneche, Camila; Calvet, Nicolas; Py, Xavier; Fernández, A. Inés; Grágeda, Mario; Ushak, Svetlana; Cabeza, Luisa F.
2016-05-01
A wide variety of potential materials for thermal energy storage (TES) have been identify depending on the implemented TES method, Sensible, latent or thermochemical. In order to improve the efficiency of TES systems more alternatives are continuously being sought. In this regard, this paper presents the review of low cost heat storage materials focused mainly in two objectives: on the one hand, the implementation of improved heat storage devices based on new appropriate materials and, on the other hand, the valorisation of waste industrial materials will have strong environmental, economic and societal benefits such as reducing the landfilled waste amounts, reducing the greenhouse emissions and others. Different industrial and municipal waste materials and by products have been considered as potential TES materials and have been characterized as such. Asbestos containing wastes, fly ashes, by-products from the salt industry and from the metal industry, wastes from recycling steel process and from copper refining process and dross from the aluminium industry, and municipal wastes (glass and nylon) have been considered. This work shows a great revalorization of wastes and by-product opportunity as TES materials, although more studies are needed to achieve industrial deployment of the idea.
Sound and heat revolutions in phononics
NASA Astrophysics Data System (ADS)
Maldovan, Martin
2013-11-01
The phonon is the physical particle representing mechanical vibration and is responsible for the transmission of everyday sound and heat. Understanding and controlling the phononic properties of materials provides opportunities to thermally insulate buildings, reduce environmental noise, transform waste heat into electricity and develop earthquake protection. Here I review recent progress and the development of new ideas and devices that make use of phononic properties to control both sound and heat. Advances in sonic and thermal diodes, optomechanical crystals, acoustic and thermal cloaking, hypersonic phononic crystals, thermoelectrics, and thermocrystals herald the next technological revolution in phononics.
Superconductive imaging surface magnetometer
Overton, Jr., William C.; van Hulsteyn, David B.; Flynn, Edward R.
1991-01-01
An improved pick-up coil system for use with Superconducting Quantum Interference Device gradiometers and magnetometers involving the use of superconducting plates near conventional pick-up coil arrangements to provide imaging of nearby dipole sources and to deflect environmental magnetic noise away from the pick-up coils. This allows the practice of gradiometry and magnetometry in magnetically unshielded environments. One embodiment uses a hemispherically shaped superconducting plate with interior pick-up coils, allowing brain wave measurements to be made on human patients. another embodiment using flat superconducting plates could be used in non-destructive evaluation of materials.
Material selection for climbing hardware using the example of a belay device
NASA Astrophysics Data System (ADS)
Semenov, E.; Schwanitz, S.; Odenwald, S.
2017-03-01
The aim of the research project was to design a novel climbing belay device. The present article describes the details of the therefor performed material selection. Literature research on the materials used in commercially available belay devices revealed a lack of definite information. Thus, a pilot x-ray fluorescence (XRF) test was performed on a small sample of common aluminium belay devices. It revealed the use of a variety of different alloy systems. The selection process continued by compiling a thorough list of constraints and objectives for this safety related piece of sports equipment. Different material options including non-aluminium-materials were discussed. The final material choice was a high strength aluminium alloy with a T6 thermal treatment. The device was designed and calculated by use of CAD and FEM software respectively, aiming to reduce weight. After manufacturing the strength, usability and friction properties of the device have been successfully tested.
Application of phase-change materials in memory taxonomy.
Wang, Lei; Tu, Liang; Wen, Jing
2017-01-01
Phase-change materials are suitable for data storage because they exhibit reversible transitions between crystalline and amorphous states that have distinguishable electrical and optical properties. Consequently, these materials find applications in diverse memory devices ranging from conventional optical discs to emerging nanophotonic devices. Current research efforts are mostly devoted to phase-change random access memory, whereas the applications of phase-change materials in other types of memory devices are rarely reported. Here we review the physical principles of phase-change materials and devices aiming to help researchers understand the concept of phase-change memory. We classify phase-change memory devices into phase-change optical disc, phase-change scanning probe memory, phase-change random access memory, and phase-change nanophotonic device, according to their locations in memory hierarchy. For each device type we discuss the physical principles in conjunction with merits and weakness for data storage applications. We also outline state-of-the-art technologies and future prospects.
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.
Environmental test program for superconducting materials and devices
NASA Technical Reports Server (NTRS)
Haertling, Gene; Randolph, Henry; Hsi, Chi-Shiung; Verbelyi, Darren
1991-01-01
This report is divided into two parts. The first dealing with work involved with Clemson University and the second with the results from Westinghouse/Savannah River. Both areas of work involved low noise, low thermal conductivity superconducting grounding links used in the NASA-sponsored Spectroscopy of the Atmosphere using Far Infrared Emission (SAFIRE) Project. Clemson prepared the links from YBa2Cu3O(7-x) superconductor tape that was mounted on a printed circuit board and encapsulated with epoxy resin. The Clemson program includes temperature vs. resistance, liquid nitrogen immersion, water immersion, thermal cycling, humidity, and radiation testing. The evaluation of the links under a long term environmental test program is described. The Savannah River program includes gamma irradiation, vibration, and long-term evaluation. The progress made in these evaluations is discussed.
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.
Microfluidic device and method for focusing, segmenting, and dispensing of a fluid stream
Jacobson, Stephen C [Knoxville, TN; Ramsey, J Michael [Knoxville, TN
2008-09-09
A microfluidic device and method for forming and dispensing minute volume segments of a material are described. In accordance with the present invention, a microfluidic device and method are provided for spatially confining the material in a focusing element. The device is also adapted for segmenting the confined material into minute volume segments, and dispensing a volume segment to a waste or collection channel. The device further includes means for driving the respective streams of sample and focusing fluids through respective channels into a chamber, such that the focusing fluid streams spatially confine the sample material. The device may also include additional means for driving a minute volume segment of the spatially confined sample material into a collection channel in fluid communication with the waste reservoir.
Microfluidic device and method for focusing, segmenting, and dispensing of a fluid stream
Jacobson, Stephen C.; Ramsey, J. Michael
2004-09-14
A microfluidic device for forming and/or dispensing minute volume segments of a material is described. In accordance with one aspect of the present invention, a microfluidic device and method is provided for spatially confining the material in a focusing element. The device is also capable of segmenting the confined material into minute volume segments, and dispensing a volume segment to a waste or collection channel. The device further includes means for driving the respective streams of sample and focusing fluids through respective channels into a chamber, such that the focusing fluid streams spatially confine the sample material. The device may also include additional means for driving a minute volume segment of the spatially confined sample material into a collection channel in fluid communication with the waste reservoir.
Magnetoelectric Energy Harvesting
2014-11-20
materials to rotating or moving machinery , make it difficult to locate piezoelectric material devices in contact with the mechanical stress generator which...mechanical energy harvesting device and more particularly relates to such a device that has a magnetostrictive and piezoelectric component. (2...makes them a candidate as the active material in energy harvesting devices. By utilizing the direct piezoelectric (or pyroelectric) effect when
NASA Technical Reports Server (NTRS)
Spring, S. E.; Clifford, J. O.; Tomko, D. L.
1997-01-01
Squirrel monkeys display an interest in novel places, habituate to new situations, and spend most of their daily activity in the wild in large groups engaging in feeding behaviors over a broad area. Captivity limits these behaviors and consequently may disrupt normal social organizations. In captivity, squirrel monkeys may exhibit stereotypical behaviors that are believed to indicate decreased psychologic well-being. When a monkey's behavior can be made to approach that seen in the wild, and stereotypical behaviors are minimal, it is assumed that psychologic well-being is adequate. Environmental enrichment devices have been used to address the Animal Welfare Act requirement that psychologic well-being of captive nonhuman primates be considered. The purpose of the study reported here was to examine whether various environmental enrichment devices improve the psychologic well-being of captive squirrel monkeys. In the study, we used behavioral observation to quantify the effectiveness of several environmental enrichment devices for reducing stereotypical behaviors in squirrel monkeys housed alone or in groups. Analysis of our results revealed that the environmental enrichment devices did not affect the expression of normal or stereotypical behaviors, but that the type of housing did.
Overview of Advanced Space Propulsion Activities in the Space Environmental Effects Team at MSFC
NASA Technical Reports Server (NTRS)
Edwards, David; Carruth, Ralph; Vaughn, Jason; Schneider, Todd; Kamenetzky, Rachel; Gray, Perry
2000-01-01
Exploration of our solar system, and beyond, requires spacecraft velocities beyond our current technological level. Technologies addressing this limitation are numerous. The Space Environmental Effects (SEE) Team at the Marshall Space Flight Center (MSFC) is focused on three discipline areas of advanced propulsion; Tethers, Beamed Energy, and Plasma. This presentation will give an overview of advanced propulsion related activities in the Space Environmental Effects Team at MSFC. Advancements in the application of tethers for spacecraft propulsion were made while developing the Propulsive Small Expendable Deployer System (ProSEDS). New tether materials were developed to meet the specifications of the ProSEDS mission and new techniques had to be developed to test and characterize these tethers. Plasma contactors were developed, tested and modified to meet new requirements. Follow-on activities in tether propulsion include the Air-SEDS activity. Beamed energy activities initiated with an experimental investigation to quantify the momentum transfer subsequent to high power, 5J, ablative laser interaction with materials. The next step with this experimental investigation is to quantify non-ablative photon momentum transfer. This step was started last year and will be used to characterize the efficiency of solar sail materials before and after exposure to Space Environmental Effects (SEE). Our focus with plasma, for propulsion, concentrates on optimizing energy deposition into a magnetically confined plasma and integration of measurement techniques for determining plasma parameters. Plasma confinement is accomplished with the Marshall Magnetic Mirror (M3) device. Initial energy coupling experiments will consist of injecting a 50 amp electron beam into a target plasma. Measurements of plasma temperature and density will be used to determine the effect of changes in magnetic field structure, beam current, and gas species. Experimental observations will be compared to predictions from computer modeling.
Wafer bonded virtual substrate and method for forming the same
Atwater, Jr., Harry A.; Zahler, James M [Pasadena, CA; Morral, Anna Fontcuberta i [Paris, FR
2007-07-03
A method of forming a virtual substrate comprised of an optoelectronic device substrate and handle substrate comprises the steps of initiating bonding of the device substrate to the handle substrate, improving or increasing the mechanical strength of the device and handle substrates, and thinning the device substrate to leave a single-crystal film on the virtual substrate such as by exfoliation of a device film from the device substrate. The handle substrate is typically Si or other inexpensive common substrate material, while the optoelectronic device substrate is formed of more expensive and specialized electro-optic material. Using the methodology of the invention a wide variety of thin film electro-optic materials of high quality can be bonded to inexpensive substrates which serve as the mechanical support for an optoelectronic device layer fabricated in the thin film electro-optic material.
Wafer bonded virtual substrate and method for forming the same
NASA Technical Reports Server (NTRS)
Atwater, Jr., Harry A. (Inventor); Zahler, James M. (Inventor); Morral, Anna Fontcuberta i (Inventor)
2007-01-01
A method of forming a virtual substrate comprised of an optoelectronic device substrate and handle substrate comprises the steps of initiating bonding of the device substrate to the handle substrate, improving or increasing the mechanical strength of the device and handle substrates, and thinning the device substrate to leave a single-crystal film on the virtual substrate such as by exfoliation of a device film from the device substrate. The handle substrate is typically Si or other inexpensive common substrate material, while the optoelectronic device substrate is formed of more expensive and specialized electro-optic material. Using the methodology of the invention a wide variety of thin film electro-optic materials of high quality can be bonded to inexpensive substrates which serve as the mechanical support for an optoelectronic device layer fabricated in the thin film electro-optic material.
NASA Astrophysics Data System (ADS)
Savina, Irina N.; Ingavle, Ganesh C.; Cundy, Andrew B.; Mikhalovsky, Sergey V.
2016-02-01
The development of bulk, three-dimensional (3D), macroporous polymers with high permeability, large surface area and large volume is highly desirable for a range of applications in the biomedical, biotechnological and environmental areas. The experimental techniques currently used are limited to the production of small size and volume cryogel material. In this work we propose a novel, versatile, simple and reproducible method for the synthesis of large volume porous polymer hydrogels by cryogelation. By controlling the freezing process of the reagent/polymer solution, large-scale 3D macroporous gels with wide interconnected pores (up to 200 μm in diameter) and large accessible surface area have been synthesized. For the first time, macroporous gels (of up to 400 ml bulk volume) with controlled porous structure were manufactured, with potential for scale up to much larger gel dimensions. This method can be used for production of novel 3D multi-component macroporous composite materials with a uniform distribution of embedded particles. The proposed method provides better control of freezing conditions and thus overcomes existing drawbacks limiting production of large gel-based devices and matrices. The proposed method could serve as a new design concept for functional 3D macroporous gels and composites preparation for biomedical, biotechnological and environmental applications.
Waste to energy – key element for sustainable waste management
DOE Office of Scientific and Technical Information (OSTI.GOV)
Brunner, Paul H., E-mail: paul.h.brunner@tuwien.ac.at; Rechberger, Helmut
2015-03-15
Highlights: • First paper on the importance of incineration from a urban metabolism point of view. • Proves that incineration is necessary for sustainable waste management. • Historical and technical overview of 100 years development of MSW incineration. - Abstract: Human activities inevitably result in wastes. The higher the material turnover, and the more complex and divers the materials produced, the more challenging it is for waste management to reach the goals of “protection of men and environment” and “resource conservation”. Waste incineration, introduced originally for volume reduction and hygienic reasons, went through a long and intense development. Together withmore » prevention and recycling measures, waste to energy (WTE) facilities contribute significantly to reaching the goals of waste management. Sophisticated air pollution control (APC) devices ensure that emissions are environmentally safe. Incinerators are crucial and unique for the complete destruction of hazardous organic materials, to reduce risks due to pathogenic microorganisms and viruses, and for concentrating valuable as well as toxic metals in certain fractions. Bottom ash and APC residues have become new sources of secondary metals, hence incineration has become a materials recycling facility, too. WTE plants are supporting decisions about waste and environmental management: They can routinely and cost effectively supply information about chemical waste composition as well as about the ratio of biogenic to fossil carbon in MSW and off-gas.« less
Strain-induced bi-thermoelectricity in tapered carbon nanotubes
NASA Astrophysics Data System (ADS)
Algharagholy, L. A. A.; Pope, T.; Lambert, C. J.
2018-03-01
We show that carbon-based nanostructured materials are a novel testbed for controlling thermoelectricity and have the potential to underpin the development of new cost-effective environmentally-friendly thermoelectric materials. In single-molecule junctions, it is known that transport resonances associated with the discrete molecular levels play a key role in the thermoelectric performance, but such resonances have not been exploited in carbon nanotubes (CNTs). Here we study junctions formed from tapered CNTs and demonstrate that such structures possess transport resonances near the Fermi level, whose energetic location can be varied by applying strain, resulting in an ability to tune the sign of their Seebeck coefficient. These results reveal that tapered CNTs form a new class of bi-thermoelectric materials, exhibiting both positive and negative thermopower. This ability to change the sign of the Seebeck coefficient allows the thermovoltage in carbon-based thermoelectric devices to be boosted by placing CNTs with alternating-sign Seebeck coefficients in tandem.
2D materials for renewable energy storage devices: Outlook and challenges.
Sahoo, Ramkrishna; Pal, Anjali; Pal, Tarasankar
2016-11-15
Scientists are looking for cost-effective, clean and durable alternative energy devices. Superior charge storage devices can easily meet the demands of our daily needs. In this respect, a material with suitable dimensions for charge storage devices has been considered to be very important. Improved performance of charge storage devices has been derived from whole-body participation and the best are from 2D materials, which provide a viable and acceptable solution.
Wood-Derived Materials for Green Electronics, Biological Devices, and Energy Applications.
Zhu, Hongli; Luo, Wei; Ciesielski, Peter N; Fang, Zhiqiang; Zhu, J Y; Henriksson, Gunnar; Himmel, Michael E; Hu, Liangbing
2016-08-24
With the arising of global climate change and resource shortage, in recent years, increased attention has been paid to environmentally friendly materials. Trees are sustainable and renewable materials, which give us shelter and oxygen and remove carbon dioxide from the atmosphere. Trees are a primary resource that human society depends upon every day, for example, homes, heating, furniture, and aircraft. Wood from trees gives us paper, cardboard, and medical supplies, thus impacting our homes, school, work, and play. All of the above-mentioned applications have been well developed over the past thousands of years. However, trees and wood have much more to offer us as advanced materials, impacting emerging high-tech fields, such as bioengineering, flexible electronics, and clean energy. Wood naturally has a hierarchical structure, composed of well-oriented microfibers and tracheids for water, ion, and oxygen transportation during metabolism. At higher magnification, the walls of fiber cells have an interesting morphology-a distinctly mesoporous structure. Moreover, the walls of fiber cells are composed of thousands of fibers (or macrofibrils) oriented in a similar angle. Nanofibrils and nanocrystals can be further liberated from macrofibrils by mechanical, chemical, and enzymatic methods. The obtained nanocellulose has unique optical, mechanical, and barrier properties and is an excellent candidate for chemical modification and reconfiguration. Wood is naturally a composite material, comprised of cellulose, hemicellulose, and lignin. Wood is sustainable, earth abundant, strong, biodegradable, biocompatible, and chemically accessible for modification; more importantly, multiscale natural fibers from wood have unique optical properties applicable to different kinds of optoelectronics and photonic devices. Today, the materials derived from wood are ready to be explored for applications in new technology areas, such as electronics, biomedical devices, and energy. The goal of this study is to review the fundamental structures and chemistries of wood and wood-derived materials, which are essential for a wide range of existing and new enabling technologies. The scope of the review covers multiscale materials and assemblies of cellulose, hemicellulose, and lignin as well as other biomaterials derived from wood, in regard to their major emerging applications. Structure-properties-application relationships will be investigated in detail. Understanding the fundamental properties of these structures is crucial for designing and manufacturing products for emerging applications. Today, a more holistic understanding of the interplay between the structure, chemistry, and performance of wood and wood-derived materials is advancing historical applications of these materials. This new level of understanding also enables a myriad of new and exciting applications, which motivate this review. There are excellent reviews already on the classical topic of woody materials, and some recent reviews also cover new understanding of these materials as well as potential applications. This review will focus on the uniqueness of woody materials for three critical applications: green electronics, biological devices, and energy storage and bioenergy.
Wood-Derived Materials for Green Electronics, Biological Devices, and Energy Applications
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zhu, Hongli; Luo, Wei; Ciesielski, Peter N.
With the arising of global climate change and resource shortage, in recent years, increased attention has been paid to environmentally friendly materials. Trees are sustainable and renewable materials, which give us shelter and oxygen and remove carbon dioxide from the atmosphere. Trees are a primary resource that human society depends upon every day, for example, homes, heating, furniture, and aircraft. Wood from trees gives us paper, cardboard, and medical supplies, thus impacting our homes, school, work, and play. All of the above-mentioned applications have been well developed over the past thousands of years. However, trees and wood have much moremore » to offer us as advanced materials, impacting emerging high-tech fields, such as bioengineering, flexible electronics, and clean energy. Wood naturally has a hierarchical structure, composed of well-oriented microfibers and tracheids for water, ion, and oxygen transportation during metabolism. At higher magnification, the walls of fiber cells have an interesting morphology--a distinctly mesoporous structure. Moreover, the walls of fiber cells are composed of thousands of fibers (or macrofibrils) oriented in a similar angle. Nanofibrils and nanocrystals can be further liberated from macrofibrils by mechanical, chemical, and enzymatic methods. The obtained nanocellulose has unique optical, mechanical, and barrier properties and is an excellent candidate for chemical modification and reconfiguration. Wood is naturally a composite material, comprised of cellulose, hemicellulose, and lignin. Wood is sustainable, earth abundant, strong, biodegradable, biocompatible, and chemically accessible for modification; more importantly, multiscale natural fibers from wood have unique optical properties applicable to different kinds of optoelectronics and photonic devices. Today, the materials derived from wood are ready to be explored for applications in new technology areas, such as electronics, biomedical devices, and energy. The goal of this study is to review the fundamental structures and chemistries of wood and wood-derived materials, which are essential for a wide range of existing and new enabling technologies. The scope of the review covers multiscale materials and assemblies of cellulose, hemicellulose, and lignin as well as other biomaterials derived from wood, in regard to their major emerging applications. Structure-properties-application relationships will be investigated in detail. Understanding the fundamental properties of these structures is crucial for designing and manufacturing products for emerging applications. Today, a more holistic understanding of the interplay between the structure, chemistry, and performance of wood and wood-derived materials is advancing historical applications of these materials. This new level of understanding also enables a myriad of new and exciting applications, which motivate this review. There are excellent reviews already on the classical topic of woody materials, and some recent reviews also cover new understanding of these materials as well as potential applications. This review will focus on the uniqueness of woody materials for three critical applications: green electronics, biological devices, and energy storage and bioenergy.« less
Global demand for rare earth resources and strategies for green mining
DOE Office of Scientific and Technical Information (OSTI.GOV)
Dutta, Tanushree
Rare earth elements (REEs) are essential raw materials for emerging renewable energy resources and ‘smart’ electronic devices. Global REE demand is slated to grow at an annual rate of 5% by 2020. This high growth rate will require a steady supply base of REEs in the long run. At present, China is responsible for 85% of global rare earth oxide (REO) production. To overcome this monopolistic supply situation, new strategies and investments are necessary to satisfy domestic supply demands. Concurrently, environmental, economic, and social problems arising from REE mining must be addressed. There is an urgent need to develop efficientmore » REE recycling techniques from end-of-life products, technologies to minimize the amount of REEs required per unit device, and methods to recover them from fly ash or fossil fuel-burning wastes.« less
Global demand for rare earth resources and strategies for green mining.
Dutta, Tanushree; Kim, Ki-Hyun; Uchimiya, Minori; Kwon, Eilhann E; Jeon, Byong-Hun; Deep, Akash; Yun, Seong-Taek
2016-10-01
Rare earth elements (REEs) are essential raw materials for emerging renewable energy resources and 'smart' electronic devices. Global REE demand is slated to grow at an annual rate of 5% by 2020. This high growth rate will require a steady supply base of REEs in the long run. At present, China is responsible for 85% of global rare earth oxide (REO) production. To overcome this monopolistic supply situation, new strategies and investments are necessary to satisfy domestic supply demands. Concurrently, environmental, economic, and social problems arising from REE mining must be addressed. There is an urgent need to develop efficient REE recycling techniques from end-of-life products, technologies to minimize the amount of REEs required per unit device, and methods to recover them from fly ash or fossil fuel-burning wastes. Copyright © 2016 Elsevier Inc. All rights reserved.
Field Effect Transistor Behavior in Electrospun Polyaniline/Polyethylene Oxide Nanofibers
NASA Technical Reports Server (NTRS)
Miranda, Felix A.; Theofylaktos, Noulie; Mueller, Carl H.; Pinto, Nicholas J.
2004-01-01
Novel transistors and logic devices based on nanotechnology concepts are under intense development. The potential for ultra-low-power circuitry makes nanotechnology attractive for applications such as digital electronics and sensors. For NASA applications, nanotechnology offers tremendous opportunities for increased onboard data processing, and thus autonomous decision-making ability, and novel sensors that detect and respond to environmental stimuli with little oversight requirements. Polyaniline (PANi) is an intriguing material because its electrical conductivity can be changed from insulating to metallic by varying the doping levels and conformations of the polymer chain, and when combined with polyethylene oxide (PEO), can be formed into nanofibers with diameters ranging from approximately 50 to 500 nm (depending on the deposition conditions). The initial goal of this work was to demonstrate transistor behavior in these nanofibers, thus creating a foundation for future logic devices.
Test device for measuring permeability of a barrier material
Reese, Matthew; Dameron, Arrelaine; Kempe, Michael
2014-03-04
A test device for measuring permeability of a barrier material. An exemplary device comprises a test card having a thin-film conductor-pattern formed thereon and an edge seal which seals the test card to the barrier material. Another exemplary embodiment is an electrical calcium test device comprising: a test card an impermeable spacer, an edge seal which seals the test card to the spacer and an edge seal which seals the spacer to the barrier material.
Hybrid membrane-microfluidic components using a novel ceramic MEMS technology
NASA Astrophysics Data System (ADS)
Lutz, Brent J.; Polyakov, Oleg; Rinaldo, Chris
2012-03-01
A novel hybrid nano/microfabrication technology has been employed to produce unique MEMS and microfluidic components that integrate nanoporous membranes. The components are made by micromachining a self-organized nanostructured ceramic material that is biocompatible and amenable to surface chemistry modification. Microfluidic structures, such as channels and wells, can be made with a precision of <2 microns. Thin-film membranes can be integrated into the bottom of these structures, featuring a wide range of possible thicknesses, from 100 micron to <50 nm. Additionally, these membranes may be non-porous or porous (with controllable pore sizes from 200 nm to <5 nm), for sophisticated size-based separations. With previous and current support from the NIH SBIR program, we have built several unique devices, and demonstrated improved separations, cell culturing, and imaging (optical and electron microscopy) versus standard products. Being ceramic, the material is much more robust to demanding environments (e.g. high and low temperatures and organic solvents), compared to polymer-based devices. Additionally, we have applied multiple surface modification techniques, including atomic layer deposition, to manipulate properties such as electrical conductivity. This microfabrication technology is highly scaleable, and thus can yield low-cost, reliable, disposable microcomponents and devices. Specific applications that can benefit from this technology includes cell culturing and assays, imaging by cryo-electron tomography, environmental sample processing, as well as many others.
Organic anodes and sulfur/selenium cathodes for advanced Li and Na batteries
NASA Astrophysics Data System (ADS)
Luo, Chao
To address energy crisis and environmental pollution induced by fossil fuels, there is an urgent demand to develop sustainable, renewable, environmental benign, low cost and high capacity energy storage devices to power electric vehicles and enhance clean energy approaches such as solar energy, wind energy and hydroenergy. However, the commercial Li-ion batteries cannot satisfy the critical requirements for next generation rechargeable batteries. The commercial electrode materials (graphite anode and LiCoO 2 cathode) are unsustainable, unrenewable and environmental harmful. Organic materials derived from biomasses are promising candidates for next generation rechargeable battery anodes due to their sustainability, renewability, environmental benignity and low cost. Driven by the high potential of organic materials for next generation batteries, I initiated a new research direction on exploring advanced organic compounds for Li-ion and Na-ion battery anodes. In my work, I employed croconic acid disodium salt and 2,5-Dihydroxy-1,4-benzoquinone disodium salt as models to investigate the effects of size and carbon coating on electrochemical performance for Li-ion and Na-ion batteries. The results demonstrate that the minimization of organic particle size into nano-scale and wrapping organic materials with graphene oxide can remarkably enhance the rate capability and cycling stability of organic anodes in both Li-ion and Na-ion batteries. To match with organic anodes, high capacity sulfur and selenium cathodes were also investigated. However, sulfur and selenium cathodes suffer from low electrical conductivity and shuttle reaction, which result in capacity fading and poor lifetime. To circumvent the drawbacks of sulfur and selenium, carbon matrixes such as mesoporous carbon, carbonized polyacrylonitrile and carbonized perylene-3, 4, 9, 10-tetracarboxylic dianhydride are employed to encapsulate sulfur, selenium and selenium sulfide. The resulting composites exhibit exceptional electrochemical performance owing to the high conductivity of carbon and effective restriction of polysulfides and polyselenides in carbon matrix, which avoids shuttle reaction.
NASA Astrophysics Data System (ADS)
Liu, Jingyuan; Li, Hongpeng; Zhang, Hongsen; Liu, Qi; Li, Rumin; Li, Bin; Wang, Jun
2018-01-01
The urgent need for sustainable development of human society has forced material scientists to explore novel materials starting from cheap natural precursors for next-generation energy storage devices by using environmentally friendly strategies. In this work, heteroatom-functionalized porous carbonaceous materials with 3D hierarchical and interconnected honeycomb-like structure have been successfully synthesized by using waste biomass pomelo peel as raw material through the combination of hydrothermal carbonization and followed KOH activation procedure. Benefiting from the unique honeycomb-like structure and high specific surface area, the as-obtained carbon material exhibits satisfactory capacitive behavior: 374 F/g at 0.1 A/g; excellent cycling stability of 92.5% capacitance retention over continuous 5000 cycles. More importantly, the as-assembled symmetric supercapacitors based on as-prepared electrode material can deliver high gravimetric and volumetric energy density of 20 W h/kg and 18.7 W h/L in 6 M KOH, respectively, as well as outstanding cycling stability. The obtained results demonstrate the possibility for taking full advantage of sustainable and large scale advanced carbon materials by choosing waste biomass, particularly the pomelo peel as a raw material.
NASA Astrophysics Data System (ADS)
Onoda, Mitsuyoshi; Malhotra, Bansi D.
2012-04-01
The 'India-Japan Workshop on Biomolecular Electronics & Organic Nanotechnology for Environment Preservation' (IJWBME 2011) will be held on 7-10 December 2011 at EGRET Himeji, Himeji, Hyogo, Japan. This workshop was held for the first time on 17-19 December 2009 at NPL, New Delhi. Keeping in mind the importance of organic nanotechnology and biomolecular electronics for environmental preservation and their anticipated impact on the economics of both the developing and the developed world, IJWBME 2009 was jointly organized by the Department of Biological Functions, Graduate School of Life Sciences and Systems Engineering, the Kyushu Institute of Technology (KIT), Kitakyushu, Japan, and the Department of Science & Technology Centre on Biomolecular Electronics (DSTCBE), National Physical Laboratory (NPL). Much progress in the field of biomolecular electronics and organic nanotechnology for environmental preservation is expected for the 21st Century. Organic optoelectronic devices, such as organic electroluminescent devices, organic thin-film transistors, organic sensors, biological systems and so on have especially attracted much attention. The main purpose of this workshop is to provide an opportunity for researchers interested in biomolecular electronics and organic nanotechnology for environmental preservation, to come together in an informal and friendly atmosphere and exchange technical knowledge and experience. We are sure that this workshop will be very useful and fruitful for all participants in summarizing the recent progress in biomolecular electronics and organic nanotechnology for environmental preservation and preparing new ground for the next generation. Many papers have been submitted from India and Japan and more than 30 papers have been accepted for presentation. The main topics of interest are as follows: Bioelectronics Biomolecular Electronics Fabrication Techniques Self-assembled Monolayers Nano-sensors Environmental Monitoring Organic Devices Organic Functional Materials We would like to express our sincere thanks to the organizing committee members of this workshop and the many organizations such as the Japan Society for the Promotion of Science (JSPS), Japan, the Department of Science & Technology (DST), India, the Society of Organic Nanometric Interfacial Controlled Electronic (NICE) Devices, the Japan Society of Applied Physics, Himeji City, Himeji Convention & Visitors Bureau, Delhi Technological University, Delhi, India and the University of Hyogo for their financial support. Thanks are also given to The Japan Society of Applied Physics, Division of Molecular Electronics and Bioelectronics, The Japan Society of Applied Physics (M & BE), the Technical Committee on Dielectric and Electrical Insulation Materials of the Institute of Electrical Engineering in Japan (IEEJ), the Technical Group on Organic Molecular Electronics, Electronics Society of the Institute of Electronics, Information and Communication Engineers (IEICE), and the IEEE Dielectrics and Electrical Insulation Society, Japan Chapter, for their cooperation. Finally, we hope that the many young and active researchers who are participating will enjoy stimulating discussions and exchange ideas with each other at IJWBME 2011, Himeji, Japan. 7 April 2011 IJWBME 2011 Chairs Mitsuyoshi Onoda Graduate School of Engineering, University of Hyogo, Himeji, Japan Bansi D Malhotra Department of Biotechnology, Delhi Technological University, Delhi, India Conference photograph Participants of the India-Japan Workshop on Biomolecular Electronics & Organic Nanotechnology for Environment Preservation 2011, December 7-10 2011, EGRET Himeji, Japan The PDF also contains a list of sponsors.
NASA Astrophysics Data System (ADS)
Lee, El-Hang; Lee, S. G.; O, B. H.; Park, S. G.; Noh, H. S.; Kim, K. H.; Song, S. H.
2006-09-01
A collective overview and review is presented on the original work conducted on the theory, design, fabrication, and in-tegration of micro/nano-scale optical wires and photonic devices for applications in a newly-conceived photonic systems called "optical printed circuit board" (O-PCBs) and "VLSI photonic integrated circuits" (VLSI-PIC). These are aimed for compact, high-speed, multi-functional, intelligent, light-weight, low-energy and environmentally friendly, low-cost, and high-volume applications to complement or surpass the capabilities of electrical PCBs (E-PCBs) and/or VLSI electronic integrated circuit (VLSI-IC) systems. These consist of 2-dimensional or 3-dimensional planar arrays of micro/nano-optical wires and circuits to perform the functions of all-optical sensing, storing, transporting, processing, switching, routing and distributing optical signals on flat modular boards or substrates. The integrated optical devices include micro/nano-scale waveguides, lasers, detectors, switches, sensors, directional couplers, multi-mode interference devices, ring-resonators, photonic crystal devices, plasmonic devices, and quantum devices, made of polymer, silicon and other semiconductor materials. For VLSI photonic integration, photonic crystals and plasmonic structures have been used. Scientific and technological issues concerning the processes of miniaturization, interconnection and integration of these systems as applicable to board-to-board, chip-to-chip, and intra-chip integration, are discussed along with applications for future computers, telecommunications, and sensor-systems. Visions and challenges toward these goals are also discussed.
Van der Waals Epitaxy of Functional Oxide Heterostructures
NASA Astrophysics Data System (ADS)
Chu, Ying-Hao
In the diligent pursuit of low-power consumption, multifunctional, and environmentally friendly electronics, more sophisticated requirements on functional materials are on demand. Recently, the discovery of 2D layered materials has created a revolution to this field. Pioneered by graphene, these new 2D materials exhibit abundant unusual physical phenomena that is undiscovered in bulk forms. These materials are characterized with their layer form and almost pure 2D electronic behavior. The confinement of charge and heat transport at such ultrathin planes offers possibilities to overcome the bottleneck of present device development in thickness limitation, and thus push the technologies into next generation. Van der Waals epitaxy, an epitaxial growth method to combine 2D and 3D materials, is one of current reliable manufacturing processes to fabricate 2D materials by growing these 2D materials epitaxially on 3D materials. Then, transferring the 2D materials to the substrates for practical applications. In the mean time, van der Waals epitaxy has also been used to create free-standing 3D materials by growing 3D materials on 2D materials and then removing them from 2D materials since the interfacial boding between 2D and 3D materials should be weak van der Waals bonds. In this study, we intend to take the same concept, but to integrate a family of functional materials in order to open new avenue to flexible electronics. Due to the interplay of lattice, charge, orbital, and spin degrees of freedom, correlated electrons in oxides generate a rich spectrum of competing phases and physical properties. Recently, lots of studies have suggested that oxide heterostructures provide a powerful route to create and manipulate the degrees of freedom and offer new possibilities for next generation devices, thus create a new playground for researchers to investigate novel physics and the emergence of fascinating states of condensed matter. In this talk, we use a 2D layered material as the substrate. And we take several oxides as examples to demonstrate a pathway to integrate 3D functional oxides on 2D layered materials.
Advanced Materials for Health Monitoring with Skin-Based Wearable Devices.
Jin, Han; Abu-Raya, Yasmin Shibli; Haick, Hossam
2017-06-01
Skin-based wearable devices have a great potential that could result in a revolutionary approach to health monitoring and diagnosing disease. With continued innovation and intensive attention to the materials and fabrication technologies, development of these healthcare devices is progressively encouraged. This article gives a concise, although admittedly non-exhaustive, didactic review of some of the main concepts and approaches related to recent advances and developments in the scope of skin-based wearable devices (e.g. temperature, strain, biomarker-analysis werable devices, etc.), with an emphasis on emerging materials and fabrication techniques in the relevant fields. To give a comprehensive statement, part of the review presents and discusses different aspects of these advanced materials, such as the sensitivity, biocompatibility and durability as well as the major approaches proposed for enhancing their chemical and physical properties. A complementary section of the review linking these advanced materials with wearable device technologies is particularly specified. Some of the strong and weak points in development of each wearable material/device are highlighted and criticized. Several ideas regarding further improvement of skin-based wearable devices are also discussed. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
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.
Compact and portable digitally controlled device for testing footwear materials: technical note.
Foto, James G
2008-01-01
Little or no practical decision-making data are available to the foot-care provider regarding the selection of orthotic materials used in therapeutic footwear. A device for simulating in-shoe forefoot conditions for the testing of orthosis materials is described. Materials are tested for their effectiveness by evaluating and comparing stress-strain and dynamic compression fatigue characteristics. The device, called the Cyclical Compression Tester (CCT), has been optimized for size, simplicity of construction, and cost. Application of the device ranges from the clinician deciding the useful life of single- and multidensity orthosis materials to the researcher characterizing materials for finite-element analysis modeling. This real-time CCT device and custom user interface combine to make an evaluation tool useful for testing how the pressure distribution of in-shoe materials changes over time in therapeutic footwear for those with peripheral neuropathy at risk for foot injury.
Are Wave and Tidal Energy Plants New Green Technologies?
Douziech, Mélanie; Hellweg, Stefanie; Verones, Francesca
2016-07-19
Wave and tidal energy plants are upcoming, potentially green technologies. This study aims at quantifying their various potential environmental impacts. Three tidal stream devices, one tidal range plant and one wave energy harnessing device are analyzed over their entire life cycles, using the ReCiPe 2008 methodology at midpoint level. The impacts of the tidal range plant were on average 1.6 times higher than the ones of hydro-power plants (without considering natural land transformation). A similar ratio was found when comparing the results of the three tidal stream devices to offshore wind power plants (without considering water depletion). The wave energy harnessing device had on average 3.5 times higher impacts than offshore wind power. On the contrary, the considered plants have on average 8 (wave energy) to 20 (tidal stream), or even 115 times (tidal range) lower impact than electricity generated from coal power. Further, testing the sensitivity of the results highlighted the advantage of long lifetimes and small material requirements. Overall, this study supports the potential of wave and tidal energy plants as alternative green technologies. However, potential unknown effects, such as the impact of turbulence or noise on marine ecosystems, should be further explored in future research.
Battery‐Supercapacitor Hybrid Devices: Recent Progress and Future Prospects
Zuo, Wenhua; Li, Ruizhi; Zhou, Cheng; Xia, Jianlong
2017-01-01
Design and fabrication of electrochemical energy storage systems with both high energy and power densities as well as long cycling life is of great importance. As one of these systems, Battery‐supercapacitor hybrid device (BSH) is typically constructed with a high‐capacity battery‐type electrode and a high‐rate capacitive electrode, which has attracted enormous attention due to its potential applications in future electric vehicles, smart electric grids, and even miniaturized electronic/optoelectronic devices, etc. With proper design, BSH will provide unique advantages such as high performance, cheapness, safety, and environmental friendliness. This review first addresses the fundamental scientific principle, structure, and possible classification of BSHs, and then reviews the recent advances on various existing and emerging BSHs such as Li‐/Na‐ion BSHs, acidic/alkaline BSHs, BSH with redox electrolytes, and BSH with pseudocapacitive electrode, with the focus on materials and electrochemical performances. Furthermore, recent progresses in BSH devices with specific functionalities of flexibility and transparency, etc. will be highlighted. Finally, the future developing trends and directions as well as the challenges will also be discussed; especially, two conceptual BSHs with aqueous high voltage window and integrated 3D electrode/electrolyte architecture will be proposed. PMID:28725528
Metal oxide charge transport material doped with organic molecules
Forrest, Stephen R.; Lassiter, Brian E.
2016-08-30
Doping metal oxide charge transport material with an organic molecule lowers electrical resistance while maintaining transparency and thus is optimal for use as charge transport materials in various organic optoelectronic devices such as organic photovoltaic devices and organic light emitting devices.
Organic photosensitive devices using subphthalocyanine compounds
Rand, Barry [Princeton, NJ; Forrest, Stephen R [Ann Arbor, MI; Mutolo, Kristin L [Hollywood, CA; Mayo, Elizabeth [Alhambra, CA; Thompson, Mark E [Anaheim Hills, CA
2011-07-05
An organic photosensitive optoelectronic device, having a donor-acceptor heterojunction of a donor-like material and an acceptor-like material and methods of making such devices is provided. At least one of the donor-like material and the acceptor-like material includes a subphthalocyanine, a subporphyrin, and/or a subporphyrazine compound; and/or the device optionally has at least one of a blocking layer or a charge transport layer, where the blocking layer and/or the charge transport layer includes a subphthalocyanine, a subporphyrin, and/or a subporphyrazine compound.
Compliant Interfacial Layers in Thermoelectric Devices
NASA Technical Reports Server (NTRS)
Firdosy, Samad A. (Inventor); Li, Billy Chun-Yip (Inventor); Ravi, Vilupanur A. (Inventor); Fleurial, Jean-Pierre (Inventor); Caillat, Thierry (Inventor); Anjunyan, Harut (Inventor)
2017-01-01
A thermoelectric power generation device is disclosed using one or more mechanically compliant and thermally and electrically conductive layers at the thermoelectric material interfaces to accommodate high temperature differentials and stresses induced thereby. The compliant material may be metal foam or metal graphite composite (e.g. using nickel) and is particularly beneficial in high temperature thermoelectric generators employing Zintl thermoelectric materials. The compliant material may be disposed between the thermoelectric segments of the device or between a thermoelectric segment and the hot or cold side interconnect of the device.
Probing material conductivity in two-terminal devices by resistance difference
NASA Astrophysics Data System (ADS)
Lu, Yang; Chen, I.-Wei
2017-08-01
It is generally impossible in two-terminal devices to separate the resistance of the device material from the parasitic resistance of terminals, interfaces, and serial loads, yet such information is needed to understand device physics. Here, we present an exact resistance-difference analysis, for a library of similarly configured two-terminal devices with self-similar material responses to external perturbations (electric current, temperature, and magnetic field), to obtain the relative conductivity change Δσ/σ in the device material using device-resistance data only. An outstanding example is nanometallic Mo/Si3N4:Pt/Pt resistance memory, in which electrons in Si3N4:Pt—the device material—display entirely different physics from those in the Pt and Mo electrodes. Our method unraveled their individual Δσ/σ, which for Si3N4:Pt exhibits self-similarity over different resistance states and film thicknesses.
Lee, Sangik; Yoon, Chansoo; Lee, Ji Hye; Kim, Yeon Soo; Lee, Mi Jung; Kim, Wondong; Baik, Jaeyoon; Jia, Quanxi; Park, Bae Ho
2018-06-06
Two-dimensional (2D)-layered semiconducting materials with considerable band gaps are emerging as a new class of materials applicable to next-generation devices. Particularly, black phosphorus (BP) is considered to be very promising for next-generation 2D electrical and optical devices because of its high carrier mobility of 200-1000 cm 2 V -1 s -1 and large on/off ratio of 10 4 to 10 5 in field-effect transistors (FETs). However, its environmental instability in air requires fabrication processes in a glovebox filled with nitrogen or argon gas followed by encapsulation, passivation, and chemical functionalization of BP. Here, we report a new method for reduction of BP-channel devices fabricated without the use of a glovebox by galvanic corrosion of an Al overlayer. The reduction of BP induced by an anodic oxidation of Al overlayer is demonstrated through surface characterization of BP using atomic force microscopy, Raman spectroscopy, and X-ray photoemission spectroscopy along with electrical measurement of a BP-channel FET. After the deposition of an Al overlayer, the FET device shows a significantly enhanced performance, including restoration of ambipolar transport, high carrier mobility of 220 cm 2 V -1 s -1 , low subthreshold swing of 0.73 V/decade, and low interface trap density of 7.8 × 10 11 cm -2 eV -1 . These improvements are attributed to both the reduction of the BP channel and the formation of an Al 2 O 3 interfacial layer resulting in a high- k screening effect. Moreover, ambipolar behavior of our BP-channel FET device combined with charge-trap behavior can be utilized for implementing reconfigurable memory and neuromorphic computing applications. Our study offers a simple device fabrication process for BP-channel FETs with high performance using galvanic oxidation of Al overlayers.
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
Polymeric Smart Skin Materials: Concepts, Materials, and Devices
2006-03-31
nanotube actuators for both sensing and active control of surfaces. State-of-the-art OLED and photovoltaic materials have been developed for display...format. 14. SUBJECT TERMS Multi-sensor paints; carbon nanotube materials and devices; OLED , 15. NUMBER OF PAGES nhntovnlthir ndni elp.trAn-nntjc ’vicn...Significant advances in organic light emitting device ( OLED ) materials has also been achieved as is evident from the publications and invention
Electronics materials research
NASA Technical Reports Server (NTRS)
1982-01-01
The electronic materials and is aimed at the establishment of quantitative relationships underlying crystal growth parameters, materials properties, electronic characteristics and device applications. The overall program evolves about the following main thrust areas: (1) crystal growth novel approaches to engineering of semiconductor materials; (2) investigation of materials properties and electronic characteristics on a macro and microscale; (3) surface properties and surface interactions with the bulk and ambients; (4) electronic properties controlling device applications and device performance.
NASA Astrophysics Data System (ADS)
Yuan, Yingchun
This dissertation develops an effective and economical system approach to reduce the environmental impact of manufacturing. The system approach is developed by using a process-based holistic method for upstream analysis and source reduction of the environmental impact of manufacturing. The system approach developed consists of three components of a manufacturing system: technology, energy and material, and is useful for sustainable manufacturing as it establishes a clear link between manufacturing system components and its overall sustainability performance, and provides a framework for environmental impact reductions. In this dissertation, the system approach developed is applied for environmental impact reduction of a semiconductor nano-scale manufacturing system, with three case scenarios analyzed in depth on manufacturing process improvement, clean energy supply, and toxic chemical material selection. The analysis on manufacturing process improvement is conducted on Atomic Layer Deposition of Al2O3 dielectric gate on semiconductor microelectronics devices. Sustainability performance and scale-up impact of the ALD technology in terms of environmental emissions, energy consumption, nano-waste generation and manufacturing productivity are systematically investigated and the ways to improve the sustainability of the ALD technology are successfully developed. The clean energy supply is studied using solar photovoltaic, wind, and fuel cells systems for electricity generation. Environmental savings from each clean energy supply over grid power are quantitatively analyzed, and costs for greenhouse gas reductions on each clean energy supply are comparatively studied. For toxic chemical material selection, an innovative schematic method is developed as a visual decision tool for characterizing and benchmarking the human health impact of toxic chemicals, with a case study conducted on six chemicals commonly used as solvents in semiconductor manufacturing. Reliability of the schematic method is validated by comparing its benchmark results on 104 chemicals with that from the conventional Human Toxicity Potential (HTP) method. This dissertation concludes with discussions on environmental impact assessment of nanotechnologies and sustainability management of nano-particles. As nano-manufacturing is emerging for wide industrial applications, improvement and expansion of the system approach would be valuable for use in the environmental management of nano-manufacturing and in the risk control of nano-particles in the interests of public health and the environment.
Self-organized porphyrin nanomaterials for solar energy harvesting
NASA Astrophysics Data System (ADS)
Radivojevic, Ivana
New concepts in the design and function of organic dyes as sensitizers for solar energy harvesting are needed. Commercial viability constrains these designs: (a) cost effective synthesis, (b) long-term stability, and (c) an important goal is to reduce the environmental impact of the product at the end of its life cycle. Simple porphyrinoid dyes meet these constraints, but new modes of incorporation into devices are needed to increase the efficiency of charge separation that drives any photonic device designed to harvest light. In this thesis, we will show how complex material architectures on surfaces need not to be the result of complex molecular structures or strong intermolecular forces that form in solution and deposit intact onto surfaces. Varying environmental conditions we can dictate morphology of self-organized structures on surfaces. These studies provide further insights into the design principles, processing, and extent of electron and energy transfer in supramolecular porphyrin materials. We are also developing a new strategy to couple porphyrinoid dyes to oxide surfaces using hafnium and zirconium metalloporphyrins and metallophthalocyanines.The mode of dye attachment to oxide surfaces is a key parameter for the construction of efficient dye sensitized solar cells. Porphyrinoid dyes containing oxophylic group (IV) metal ions that protrude from on face of the macrocycle allow connections directly to oxide surfaces, wherein the metal ion serves as the conduit. Since the charge transport efficiency is mediated by appropriate matching of molecular HOMO-LUMO gaps to semiconductor band gaps, we will show characterized solution phase ground and excited redox potentials of these dyes, and also photophysical properties of dye excited state using transient absorbance spectroscopy.
Localized electrical fine tuning of passive microwave and radio frequency devices
Findikoglu, Alp T.
2001-04-10
A method and apparatus for the localized electrical fine tuning of passive multiple element microwave or RF devices in which a nonlinear dielectric material is deposited onto predetermined areas of a substrate containing the device. An appropriate electrically conductive material is deposited over predetermined areas of the nonlinear dielectric and the signal line of the device for providing electrical contact with the nonlinear dielectric. Individual, adjustable bias voltages are applied to the electrically conductive material allowing localized electrical fine tuning of the devices. The method of the present invention can be applied to manufactured devices, or can be incorporated into the design of the devices so that it is applied at the time the devices are manufactured. The invention can be configured to provide localized fine tuning for devices including but not limited to coplanar waveguides, slotline devices, stripline devices, and microstrip devices.
NASA Technical Reports Server (NTRS)
Besser, P. J.
1976-01-01
Bubble domain materials and devices are discussed. One of the materials development goals was a materials system suitable for operation of 16 micrometer period bubble domain devices at 150 kHz over the temperature range -10 C to +60 C. Several material compositions and hard bubble suppression techniques were characterized and the most promising candidates were evaluated in device structures. The technique of pulsed laser stroboscopic microscopy was used to characterize bubble dynamic properties and device performance at 150 kHz. Techniques for large area LPE film growth were developed as a separate task. Device studies included detector optimization, passive replicator design and test and on-chip bridge evaluation. As a technology demonstration an 8 chip memory cell was designed, tested and delivered. The memory elements used in the cell were 10 kilobit serial registers.
NASA Astrophysics Data System (ADS)
Savant, Gajendra D.; Jannson, Joanna L.
1991-07-01
The increased emphasis on speed of operation, wavelength selectivity, compactness, and ruggedization has focused a great deal of attention on the solutions offered by all-optic devices and by hybrid electro-optic systems. In fact, many photonic devices are being considered for use as partial replacements for electronic systems. Optical components, which include modulators, switches, 3-D memory storage devices, wavelength division multiplexers, holographic optical elements, and others, are examples of such devices. The success or failure of these modern optical devices depends, to a great extent, on the performance and survivability of the optical materials used. This is particularly true for volume holographic filters, organic memory media, second- and third-order nonlinear material-based processors and neural networks. Due to the critical importance of these materials and their lack of availability, Physical Optics Corporation (POC) undertook a global advanced optical materials program which has enabled it to introduce several optical devices, based on the new and improved materials which will be described in this article.
A study of the suitability of ferrite for use in low-field insertion devices
DOE Office of Scientific and Technical Information (OSTI.GOV)
Johnson, K.; Hassenzahl, W.V.
1995-02-01
Most insertion devices built to date use rare-earth permanent-magnet materials, which have a high remanent field and are more expensive than many other permanent-magnet materials. Low-field insertion devices could use less-expensive, lower performance magnetic materials if they had suitable magnetic characteristics. These materials must be resistant to demagnetization during construction and operation of the insertion device, have uniform magnetization, possess low minor-axis magnetic moments, and have small minor field components on the surfaces. This paper describes an investigation to determine if ferrite possesses magnetic qualities suitable for insertion device applications. The type of ferrite investigated, MMPA Ceramic 8 from Stackpolemore » Inc., was found to be acceptable for insertion device applications.« less
Kumar, S; Dhar, A
2016-07-20
Organometal halide perovskite materials are presently some of the pacesetters for light harvesting in hybrid photovoltaic devices because of their excellent inherent electrical and optical properties. However, long-term durability of such perovskite materials remains a major bottleneck for their commercialization especially in countries with hot and humid climatic conditions, thus violating the international standards for photovoltaic technology. Albeit, TiO2 as an electron-transport layer has been well investigated for perovskite solar cells; the high-temperature processing makes it unsuitable for low-cost and large-scale roll-to-roll production of flexible photovoltaic devices. Herein, we have chosen low-temperature (<150 °C)-processable nanostructured ZnO as the electron-selective layer and used a two-step method for sensitizing ZnO nanorods with methylammonium lead iodide (MAPbI3) perovskite, which is viable for flexible photovoltaic devices. We have also elaborately addressed the effect of the annealing duration on the conversion of a precursor solution into the required perovskite phase on ZnO nanostructures. The investigations show that the presence of ZnO nanostructures accelerates the rate of degradation of MAPbI3 films under ambient annealing and thus requires proper optimization. The role of ZnO in enhancing the degradation kinetics of the perovskite layer has been investigated by X-ray photoelectron spectroscopy and a buffer layer passivation technique. The effect of the annealing duration of the MAPbI3 perovskite on the optical, morphological, and compositional behavior has been closely studied and correlated with the photovoltaic efficiency. The study captures the degradation behavior of the commercially interesting MAPbI3 perovskite on a ZnO electron-transport layer and thus can provide insight for developing alternative families of perovskite material with better thermal and environmental stability for application in low-cost flexible photovoltaic technology.
Application of phase-change materials in memory taxonomy
Wang, Lei; Tu, Liang; Wen, Jing
2017-01-01
Abstract Phase-change materials are suitable for data storage because they exhibit reversible transitions between crystalline and amorphous states that have distinguishable electrical and optical properties. Consequently, these materials find applications in diverse memory devices ranging from conventional optical discs to emerging nanophotonic devices. Current research efforts are mostly devoted to phase-change random access memory, whereas the applications of phase-change materials in other types of memory devices are rarely reported. Here we review the physical principles of phase-change materials and devices aiming to help researchers understand the concept of phase-change memory. We classify phase-change memory devices into phase-change optical disc, phase-change scanning probe memory, phase-change random access memory, and phase-change nanophotonic device, according to their locations in memory hierarchy. For each device type we discuss the physical principles in conjunction with merits and weakness for data storage applications. We also outline state-of-the-art technologies and future prospects. PMID:28740557
Passive safety device and internal short tested method for energy storage cells and systems
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.
High efficiency photovoltaic device
Guha, Subhendu; Yang, Chi C.; Xu, Xi Xiang
1999-11-02
An N-I-P type photovoltaic device includes a multi-layered body of N-doped semiconductor material which has an amorphous, N doped layer in contact with the amorphous body of intrinsic semiconductor material, and a microcrystalline, N doped layer overlying the amorphous, N doped material. A tandem device comprising stacked N-I-P cells may further include a second amorphous, N doped layer interposed between the microcrystalline, N doped layer and a microcrystalline P doped layer. Photovoltaic devices thus configured manifest improved performance, particularly when configured as tandem devices.
Methods of forming semiconductor devices and devices formed using such methods
Fox, Robert V; Rodriguez, Rene G; Pak, Joshua
2013-05-21
Single source precursors are subjected to carbon dioxide to form particles of material. The carbon dioxide may be in a supercritical state. Single source precursors also may be subjected to supercritical fluids other than supercritical carbon dioxide to form particles of material. The methods may be used to form nanoparticles. In some embodiments, the methods are used to form chalcopyrite materials. Devices such as, for example, semiconductor devices may be fabricated that include such particles. Methods of forming semiconductor devices include subjecting single source precursors to carbon dioxide to form particles of semiconductor material, and establishing electrical contact between the particles and an electrode.
Germanium Based Field-Effect Transistors: Challenges and Opportunities
Goley, Patrick S.; Hudait, Mantu K.
2014-01-01
The performance of strained silicon (Si) as the channel material for today’s metal-oxide-semiconductor field-effect transistors may be reaching a plateau. New channel materials with high carrier mobility are being investigated as alternatives and have the potential to unlock an era of ultra-low-power and high-speed microelectronic devices. Chief among these new materials is germanium (Ge). This work reviews the two major remaining challenges that Ge based devices must overcome if they are to replace Si as the channel material, namely, heterogeneous integration of Ge on Si substrates, and developing a suitable gate stack. Next, Ge is compared to compound III-V materials in terms of p-channel device performance to review how it became the first choice for PMOS devices. Different Ge device architectures, including surface channel and quantum well configurations, are reviewed. Finally, state-of-the-art Ge device results and future prospects are also discussed. PMID:28788569
Full space device optimization for solar cells.
Baloch, Ahmer A B; Aly, Shahzada P; Hossain, Mohammad I; El-Mellouhi, Fedwa; Tabet, Nouar; Alharbi, Fahhad H
2017-09-20
Advances in computational materials have paved a way to design efficient solar cells by identifying the optimal properties of the device layers. Conventionally, the device optimization has been governed by single or double descriptors for an individual layer; mostly the absorbing layer. However, the performance of the device depends collectively on all the properties of the material and the geometry of each layer in the cell. To address this issue of multi-property optimization and to avoid the paradigm of reoccurring materials in the solar cell field, a full space material-independent optimization approach is developed and presented in this paper. The method is employed to obtain an optimized material data set for maximum efficiency and for targeted functionality for each layer. To ensure the robustness of the method, two cases are studied; namely perovskite solar cells device optimization and cadmium-free CIGS solar cell. The implementation determines the desirable optoelectronic properties of transport mediums and contacts that can maximize the efficiency for both cases. The resulted data sets of material properties can be matched with those in materials databases or by further microscopic material design. Moreover, the presented multi-property optimization framework can be extended to design any solid-state device.
Zou, Nan; Yuan, Chunhao; Liu, Shaowen; Han, Yongtao; Li, Yanjie; Zhang, Jialei; Xu, Xiang; Li, Xuesheng; Pan, Canping
2016-07-29
An analytical method based on stir bar sorptive extraction (SBSE) coupled with pulse glow discharge-ion mobility spectrometry (PGD-IMS) was developed for analysis of three triazine pesticide residues in water and soil samples. An injection port with sealing device and stir bars hold device were designed and constructed to directly position the SBSE fiber including the extracted samples into the heating device, making desorption and detection of analytes proceeded simultaneously. The extraction conditions such as SBSE solid phase material, extraction time, extraction temperature, pH value and salt concentration were optimized. Mixture of MWCNTs-COOH and PDMS were shown to be effective in enriching the triazines. The LODs and LOQs of three triazines were found to be 0.006-0.015μgkg(-1) and 0.02-0.05μgkg(-1), and the linear range was 0.05-10μgL(-1) with determination coefficients from 0.9987 to 0.9993. The SBSE-PGD-IMS method was environmentally friendly without organic solvent consumption in the entire experimental procedures, and it was demonstrated to be a commendable rapid analysis technique for analysis of triazine pesticide residues in environmental samples on site. The proposed method was applied for the analysis of real ground water, surface water and soil samples. Copyright © 2016 Elsevier B.V. All rights reserved.
White, C C; Tan, K T; O'Brien, E P; Hunston, D L; Chin, J W; Williams, R S
2011-02-01
The paper describes the development, implementation, and testing of two thermally driven outdoor exposure instruments. These devices are unique in their ability to impose field generated thermally induced strain on sealant specimens while monitoring their resulting load and displacement. The instruments combine a fixed wood and steel supporting frame with a moving polyvinyl chloride frame, and employ differences in the coefficients of thermal expansion between the supporting frame and moving frame to induce strain on the sealant specimens. Two different kinds of instruments have been fabricated, "winter/tension" and "winter/compression" designs. In the winter/tension design, the thermally induced dimensional change is directly transferred to the specimens; while in the winter/compression design, the samples are loaded in an opposite direction with the dimensional change. Both designs are instrumented to monitor load and displacement and are built so that the strain on the specimen does not exceed ±25% over the range of temperatures expected in Gaithersburg, MD. Additionally, a weather station is colocated with the device to record environmental conditions in 1 min intervals. This combination of weather information with mechanical property data enables a direct link between environmental conditions and the corresponding sealant response. The reliability and effectiveness of these instruments are demonstrated with a typical sealant material. The results show that the instruments work according to the design criteria and provide a meaningful quantitative platform to monitor the mechanical response of sealant exposed to outdoor weathering.
Wang, Hua; Feng, Hongbin; Li, Jinghong
2014-06-12
Being confronted with the energy crisis and environmental problems, the exploration of clean and renewable energy materials as well as their devices are urgently demanded. Two-dimensional (2D) atomically-thick materials, graphene and grpahene-like layered transition metal dichalcogenides (TMDs), have showed vast potential as novel energy materials due to their unique physicochemical properties. In this Review, we outline the typical application of graphene and grpahene-like TMDs in energy conversion and storage fields, and hope to promote the development of 2D TMDs in this field through the analysis and comparisons with the relatively natural graphene. First, a brief introduction of electronic structures and basic properties of graphene and TMDs are presented. Then, we summarize the exciting progress of these materials made in both energy conversion and storage field including solar cells, electrocatalysis, supercapacitors and lithium ions batteries. Finally, the prospects and further developments in these exciting fields of graphene and graphene-like TMDs materials are also suggested. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
EDITORIAL: Design and function of molecular and bioelectronics devices
NASA Astrophysics Data System (ADS)
Krstic, Predrag; Forzani, Erica; Tao, Nongjian; Korkin, Anatoli
2007-10-01
Further rapid progress of electronics, in particular the increase of computer power and breakthroughs in sensor technology for industrial, medical diagnostics and environmental applications, strongly depends on the scaling of electronic devices, ultimately to the size of molecules. Design of controllable molecular-scale devices may resolve the problem of energy dissipation at the nanoscale and take advantage of molecular self-assembly in the so-called bottom-up approach. This special issue of Nanotechnology is devoted to a better understanding of the function and design of molecular-scale devices that are relevant to future electronics and sensor technology. Papers contained in this special issue are selected from the symposium Nano and Giga Challenges in Electronics and Photonics: From Atoms to Materials to Devices to System Architecture (12-16 March, 2007, Phoenix, Arizona, USA), as well as from original and novel scientific contributions of invited world-renown researchers. It addresses both theoretical and experimental achievements in the fields of molecular and bioelectronics, chemical and biosensors at the molecular level, including carbon nanotubes, novel nanostructures, as well as related research areas and industrial applications. The conference series Nano and Giga Challenges in Electronics and Photonics was launched as a truly interdisciplinary forum to bridge scientists and engineers to work across boundaries in the design of future information technologies, from atoms to materials to devices to system architecture. Following the first two successful meetings in Moscow, Russia (NGCM2002) and Krakow, Poland (NGCM2004), the third Nano and Giga Forum (NGC2007) was held in 2007 hosted by Arizona State University. Besides this special issue of Nanotechnology, two other collections (in the journal Solid State Electronics and the tutorial book in the series Nanostructure Science and Technology Springer) have published additional selected and invited papers from NGC2007. The NGC2007 meeting, which included two days of tutorials (Spring School) and a three day symposium, attracted approximately 400 participants from academic, industrial and governmental research institutions from 41 countries, and covered recent developments in the fabrication and functionality of nano-scale materials, devices and system architecture from advanced CMOS to molecular electronics, photonics, optoelectronics and magnetic materials and devices. The success of the conference would not have been possible without generous support from many sponsors and research institutions, especially from Arizona State University (conference host and co-organizer), International Science and Technology Center (ISTC), National Science Foundation (NSFT), Defense Advanced Research Agency (DARPA), Office of Naval Research, Army Research Office, Computational Chemistry List (CCL), Springer Publisher, City of Tempe, STMicroelectronics, Quarles & Brady LLP, Oak Ridge National Laboratory, Canadian Consulate in Phoenix, Salt River Project (SRP) and many other local, national and international and individual supporters. We would like to acknowledge the shared responsibility for this special issue of Nanotechnology on molecular and bioelectronics, and the highly professional support from Dr Nina Couzin, Dr Alex Wotherspoon and the Nanotechnology team from the IOP Publishing. We also acknowledge the exception made in allowing the publication of some material that is outside the normal scope of Nanotechnology.
Design and function of molecular and bioelectronics devices.
Krstic, Predrag; Forzani, Erica; Tao, Nongjian; Korkin, Anatoli
2007-10-24
Further rapid progress of electronics, in particular the increase of computer power and breakthroughs in sensor technology for industrial, medical diagnostics and environmental applications, strongly depends on the scaling of electronic devices, ultimately to the size of molecules. Design of controllable molecular-scale devices may resolve the problem of energy dissipation at the nanoscale and take advantage of molecular self-assembly in the so-called bottom-up approach. This special issue of Nanotechnology is devoted to a better understanding of the function and design of molecular-scale devices that are relevant to future electronics and sensor technology. Papers contained in this special issue are selected from the symposium Nano and Giga Challenges in Electronics and Photonics: From Atoms to Materials to Devices to System Architecture (12-16 March, 2007, Phoenix, Arizona, USA), as well as from original and novel scientific contributions of invited world-renown researchers. It addresses both theoretical and experimental achievements in the fields of molecular and bioelectronics, chemical and biosensors at the molecular level, including carbon nanotubes, novel nanostructures, as well as related research areas and industrial applications. The conference series Nano and Giga Challenges in Electronics and Photonics was launched as a truly interdisciplinary forum to bridge scientists and engineers to work across boundaries in the design of future information technologies, from atoms to materials to devices to system architecture. Following the first two successful meetings in Moscow, Russia (NGCM2002) and Krakow, Poland (NGCM2004), the third Nano and Giga Forum (NGC2007) was held in 2007 hosted by Arizona State University. Besides this special issue of Nanotechnology, two other collections (in the journal Solid State Electronics and the tutorial book in the series Nanostructure Science and Technology Springer) have published additional selected and invited papers from NGC2007. The NGC2007 meeting, which included two days of tutorials (Spring School) and a three day symposium, attracted approximately 400 participants from academic, industrial and governmental research institutions from 41 countries, and covered recent developments in the fabrication and functionality of nano-scale materials, devices and system architecture from advanced CMOS to molecular electronics, photonics, optoelectronics and magnetic materials and devices. The success of the conference would not have been possible without generous support from many sponsors and research institutions, especially from Arizona State University (conference host and co-organizer), International Science and Technology Center (ISTC), National Science Foundation (NSFT), Defense Advanced Research Agency (DARPA), Office of Naval Research, Army Research Office, Computational Chemistry List (CCL), Springer Publisher, City of Tempe, STMicroelectronics, Quarles & Brady LLP, Oak Ridge National Laboratory, Canadian Consulate in Phoenix, Salt River Project (SRP) and many other local, national and international and individual supporters. We would like to acknowledge the shared responsibility for this special issue of Nanotechnology on molecular and bioelectronics, and the highly professional support from Dr Nina Couzin, Dr Alex Wotherspoon and the Nanotechnology team from the IOP Publishing. We also acknowledge the exception made in allowing the publication of some material that is outside the normal scope of Nanotechnology.
Code of Federal Regulations, 2013 CFR
2013-01-01
... accidents; (iv) For devices containing byproduct material, the radiation profile of a prototype device; (v... source or device pertinent to an evaluation of its radiation safety, including: (i) The byproduct...) Instructions for handling and storing the source or device from the radiation safety standpoint; these...
Code of Federal Regulations, 2014 CFR
2014-01-01
... accidents; (iv) For devices containing byproduct material, the radiation profile of a prototype device; (v... source or device pertinent to an evaluation of its radiation safety, including: (i) The byproduct...) Instructions for handling and storing the source or device from the radiation safety standpoint; these...
CMOS compatible electrode materials selection in oxide-based memory devices
NASA Astrophysics Data System (ADS)
Zhuo, V. Y.-Q.; Li, M.; Guo, Y.; Wang, W.; Yang, Y.; Jiang, Y.; Robertson, J.
2016-07-01
Electrode materials selection guidelines for oxide-based memory devices are constructed from the combined knowledge of observed device operation characteristics, ab-initio calculations, and nano-material characterization. It is demonstrated that changing the top electrode material from Ge to Cr to Ta in the Ta2O5-based memory devices resulted in a reduction of the operation voltages and current. Energy Dispersed X-ray (EDX) Spectrometer analysis clearly shows that the different top electrode materials scavenge oxygen ions from the Ta2O5 memory layer at various degrees, leading to different oxygen vacancy concentrations within the Ta2O5, thus the observed trends in the device performance. Replacing the Pt bottom electrode material with CMOS compatible materials (Ru and Ir) further reduces the power consumption and can be attributed to the modification of the Schottky barrier height and oxygen vacancy concentration at the electrode/oxide interface. Both trends in the device performance and EDX results are corroborated by the ab-initio calculations which reveal that the electrode material tunes the oxygen vacancy concentration via the oxygen chemical potential and defect formation energy. This experimental-theoretical approach strongly suggests that the proper selection of CMOS compatible electrode materials will create the critical oxygen vacancy concentration to attain low power memory performance.
Micro-opto-mechanical devices and systems using epitaxial lift off
NASA Technical Reports Server (NTRS)
Camperi-Ginestet, C.; Kim, Young W.; Wilkinson, S.; Allen, M.; Jokerst, N. M.
1993-01-01
The integration of high quality, single crystal thin film gallium arsenide (GaAs) and indium phosphide (InP) based photonic and electronic materials and devices with host microstructures fabricated from materials such as silicon (Si), glass, and polymers will enable the fabrication of the next generation of micro-opto-mechanical systems (MOMS) and optoelectronic integrated circuits. Thin film semiconductor devices deposited onto arbitrary host substrates and structures create hybrid (more than one material) near-monolithic integrated systems which can be interconnected electrically using standard inexpensive microfabrication techniques such as vacuum metallization and photolithography. These integrated systems take advantage of the optical and electronic properties of compound semiconductor devices while still using host substrate materials such as silicon, polysilicon, glass and polymers in the microstructures. This type of materials optimization for specific tasks creates higher performance systems than those systems which must use trade-offs in device performance to integrate all of the function in a single material system. The low weight of these thin film devices also makes them attractive for integration with micromechanical devices which may have difficulty supporting and translating the full weight of a standard device. These thin film devices and integrated systems will be attractive for applications, however, only when the development of low cost, high yield fabrication and integration techniques makes their use economically feasible. In this paper, we discuss methods for alignment, selective deposition, and interconnection of thin film epitaxial GaAs and InP based devices onto host substrates and host microstructures.
Non-binary Colour Modulation for Display Device Based on Phase Change Materials.
Ji, Hong-Kai; Tong, Hao; Qian, Hang; Hui, Ya-Juan; Liu, Nian; Yan, Peng; Miao, Xiang-Shui
2016-12-19
A reflective-type display device based on phase change materials is attractive because of its ultrafast response time and high resolution compared with a conventional display device. This paper proposes and demonstrates a unique display device in which multicolour changing can be achieved on a single device by the selective crystallization of double layer phase change materials. The optical contrast is optimized by the availability of a variety of film thicknesses of two phase change layers. The device exhibits a low sensitivity to the angle of incidence, which is important for display and colour consistency. The non-binary colour rendering on a single device is demonstrated for the first time using optical excitation. The device shows the potential for ultrafast display applications.
NASA Astrophysics Data System (ADS)
Marshall, Kenneth L.; Adlesberger, Kathleen; Kolodzie, Benjamin; Myhre, Graham; Griffin, DeVon W.
2005-08-01
By design, point-diffraction interferometers are much less sensitive to environmental disturbances than dual-path interferometers, but, until very recently, have not been capable of phase shifting. The liquid crystal point-diffraction interferometer (LCPDI) utilizes a dye-doped, liquid crystal (LC) electro-optical device that functions as both the point-diffraction source and the phase-shifting element, yielding a phase-shifting diagnostic device that is significantly more compact and robust while using fewer optical elements than conventional dual-path interferometers. These attributes make the LCPDI of special interest for diagnostic applications in the scientific, commercial, military, and industrial sectors, where vibration insensitivity, power requirements, size, weight, and cost are critical issues. Until very recently, LCPDI devices have used a plastic microsphere embedded in the LC fluid layer as the point-diffraction source. The process for fabricating microsphere-based LCPDI devices is low-yield, labor-intensive, and very "hands-on" great care and skill are required to produce devices with adequate interference fringe contrast for diagnostic measurements. With the goal of evolving the LCPDI beyond the level of a laboratory prototype in mind, we have developed "second-generation" LCPDI devices in which the reference-diffracting elements are an integral part of the substrates by depositing a suitable optical material (vapor-deposited thin films or photoresist) directly onto the substrate surface. These "structured" substrates eliminate many of the assembly difficulties and performance limitations of current LCPDI devices as well as open the possibility of mass-producing LCPDI devices at low cost by the same processes used to manufacture commercial LC displays.
10 CFR 32.31 - Certain industrial devices containing byproduct material: Safety criteria.
Code of Federal Regulations, 2014 CFR
2014-01-01
... Certain industrial devices containing byproduct material: Safety criteria. (a) An applicant for a license... 10 Energy 1 2014-01-01 2014-01-01 false Certain industrial devices containing byproduct material: Safety criteria. 32.31 Section 32.31 Energy NUCLEAR REGULATORY COMMISSION SPECIFIC DOMESTIC LICENSES TO...
10 CFR 32.31 - Certain industrial devices containing byproduct material: Safety criteria.
Code of Federal Regulations, 2013 CFR
2013-01-01
... Certain industrial devices containing byproduct material: Safety criteria. (a) An applicant for a license... 10 Energy 1 2013-01-01 2013-01-01 false Certain industrial devices containing byproduct material: Safety criteria. 32.31 Section 32.31 Energy NUCLEAR REGULATORY COMMISSION SPECIFIC DOMESTIC LICENSES TO...
Thermoelectric materials and devices
NASA Technical Reports Server (NTRS)
Park, Yeonjoon (Inventor); Choi, Sang H. (Inventor); King, Glen C. (Inventor); Elliott, James R. (Inventor); Talcott, Noel A. (Inventor)
2011-01-01
New thermoelectric materials comprise highly [111]-oriented twinned group IV alloys on the basal plane of trigonal substrates, which exhibit a high thermoelectric figure of merit and good material performance, and devices made with these materials.
Superdetonation devices and methods for making and using the same
DOE Office of Scientific and Technical Information (OSTI.GOV)
McGrane, Shawn D.
Disclosed herein are embodiments of devices comprising energetic materials capable of superdetonation and methods of making and using such devices. The devices disclosed herein comprise components, dimensions, and configurations optimized to utilize superdetonation velocities produced by the energetic materials disclosed herein.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Zschech, Ehrenfried; Sinclair, Robert; Kempen, Paul Joseph
2014-04-30
Here, this article describes the establishment, over a period of 10 years or so, of a multi-user, institution-wide facility for the characterization of materials and devices at the nanoscale. Emphasis is placed on the type of equipment that we have found to be most useful for our users, and the business strategy that maintains its operations. A central component of our facility is an aberration-corrected environmental transmission electron microscope and its application is summarized in the studies of plasmon energies of silver nanoparticles, the band gap of PbS quantum dots, atomic site occupancy near grain boundaries in yttria stabilized zirconia,more » the lithiation of silicon nanoparticles, in situ observations on carbon nanotube oxidation and the electron tomography of varicella zoster virus nucleocapsids.« less
Photochromic, electrochromic, photoelectrochromic and photovoltaic devices
Kostecki, Robert; McLarnon, Frank R.
2000-01-01
A light activated photoelectrochromic device is formed of a two-component system formed of a photoactive charge carrier generating material and electrochromic material (plus an elecrolyte). Light interacts with a semiconductive material to generate hole-electron charge carriers which cause a redox reaction in the electrochromic material. One device is formed of hydrated nickel oxide as the electrochromic layer and polycrystalline titanium dioxide as the charge generating material. The materials may be formed as discrete layers or mixed together. Because of the direct charge transfer between the layers, a circuit to apply a voltage to drive the electrochromic reaction is not required, although one can be used to enhance the reaction. The hydrated nickel oxide-titanium dioxide materials can also be used to form a photovoltaic device for generating electricity.
Transfer having a coupling coefficient higher than its active material
NASA Technical Reports Server (NTRS)
Lesieutre, George A. (Inventor); Davis, Christopher L. (Inventor)
2001-01-01
A coupling coefficient is a measure of the effectiveness with which a shape-changing material (or a device employing such a material) converts the energy in an imposed signal to useful mechanical energy. Device coupling coefficients are properties of the device and, although related to the material coupling coefficients, are generally different from them. This invention describes a class of devices wherein the apparent coupling coefficient can, in principle, approach 1.0, corresponding to perfect electromechanical energy conversion. The key feature of this class of devices is the use of destabilizing mechanical pre-loads to counter inherent stiffness. The approach is illustrated for piezoelectric and thermoelectrically actuated devices. The invention provides a way to simultaneously increase both displacement and force, distinguishing it from alternatives such as motion amplification, and allows transducer designers to achieve substantial performance gains for actuator and sensor devices.
Environmental considerations for application of high Tc superconductors in space
NASA Technical Reports Server (NTRS)
Carlberg, I. A.; Kelliher, W. C.; Wise, S. A.; Hooker, M. W.; Buckley, J. D.
1993-01-01
The impact of the environmental factors on the performance of the superconductive devices during spaceflight missions is reviewed. Specific factors typical of spaceflight are addressed to evaluate superconductive devices for space-based applications including preflight storage, radiation, vibration, and thermal cycling.
Heavy Metal-Free Tannin from Bark for Sustainable Energy Storage.
Mukhopadhyay, Alolika; Jiao, Yucong; Katahira, Rui; Ciesielski, Peter N; Himmel, Michael; Zhu, Hongli
2017-12-13
A novel renewable cathode made from earth abundant, low-cost materials can contribute to the intermittent storage needs of renewable energy-based society. In this work, we report for the first-time tannin from Nature as a cathode material. Our approach exploits the charge storage mechanism of the redox active quinone moiety. Tannins extracted from tree bark using environmental friendly aqueous solvents have the highest phenol content (5.56 mol g -1 ) among all the natural phenolic biopolymers, 5000 times higher than lignin. Tannins coupled with a conductive polymer polypyrrole acquire high specific capacitance values of 370 F g -1 at 0.5 A g -1 as well as excellent rate performance of 196 F g -1 at 25 A g -1 . Additionally, we employed carbonized wood as an electrode substrate to produce a sustainable electrochemical device with dramatically improved performance compared to conventional devices. The high surface area provided by the well-aligned, cellular porosity of wood-derived substrate combined with the high mobility of ions and electrons in the carbonized cell walls and deposited tannin can achieve an areal capacitance of 4.6 F cm -2 at 1 mA cm -2 , which is 1.5 times higher than activated wood carbon.
On the need for a biomimetic breast device
NASA Astrophysics Data System (ADS)
Danos, Nicole; German, Rebecca
2016-11-01
The function of the mammary gland, a key anatomical innovation that led to the rise of mammals, is governed by solid-fluid mechanics. There is strong evidence that these mechanical interactions regulate the production of milk and the transport of milk through the lactiferous ducts and into the infant's mouth. Solid-fluid mechanics determine the rate of milk flow and therefore may affect the safe coordination of sucking, swallowing and breathing in the infant. Additionally, links between breastfeeding, the material properties of the gland and breast cancer have been shown repeatedly. However, there is to date no direct way of characterizing breast mechanics during the physiological function for which it has evolved: infant feeding. We are developing an engineered biomimetic breast in which we can experimentally manipulate both structural and material properties of the gland. The device will be tested with an animal model of infant feeding, the pig, to measure the direct effect of gland mechanics on infant feeding. Data from these studies may lead to better designed feeding bottles for infants, milk pumps for both humans and agricultural mammals, and will provide the control mechanical environmental for studies of breast cancer mechanobiology.
Symmetric Electrodes for Electrochemical Energy-Storage Devices.
Zhang, Lei; Dou, Shi Xue; Liu, Hua Kun; Huang, Yunhui; Hu, Xianluo
2016-12-01
Increasing environmental problems and energy challenges have so far attracted urgent demand for developing green and efficient energy-storage systems. Among various energy-storage technologies, sodium-ion batteries (SIBs), electrochemical capacitors (ECs) and especially the already commercialized lithium-ion batteries (LIBs) are playing very important roles in the portable electronic devices or the next-generation electric vehicles. Therefore, the research for finding new electrode materials with reduced cost, improved safety, and high-energy density in these energy storage systems has been an important way to satisfy the ever-growing demands. Symmetric electrodes have recently become a research focus because they employ the same active materials as both the cathode and anode in the same energy-storage system, leading to the reduced manufacturing cost and simplified fabrication process. Most importantly, this feature also endows the symmetric energy-storage system with improved safety, longer lifetime, and ability of charging in both directions. In this Progress Report, we provide the comprehensive summary and comment on different symmetric electrodes and focus on the research about the applications of symmetric electrodes in different energy-storage systems, such as the above mentioned SIBs, ECs and LIBs. Further considerations on the possibility of mass production have also been presented.
Electronic waste management approaches: an overview.
Kiddee, Peeranart; Naidu, Ravi; Wong, Ming H
2013-05-01
Electronic waste (e-waste) is one of the fastest-growing pollution problems worldwide given the presence if a variety of toxic substances which can contaminate the environment and threaten human health, if disposal protocols are not meticulously managed. This paper presents an overview of toxic substances present in e-waste, their potential environmental and human health impacts together with management strategies currently being used in certain countries. Several tools including life cycle assessment (LCA), material flow analysis (MFA), multi criteria analysis (MCA) and extended producer responsibility (EPR) have been developed to manage e-wastes especially in developed countries. The key to success in terms of e-waste management is to develop eco-design devices, properly collect e-waste, recover and recycle material by safe methods, dispose of e-waste by suitable techniques, forbid the transfer of used electronic devices to developing countries, and raise awareness of the impact of e-waste. No single tool is adequate but together they can complement each other to solve this issue. A national scheme such as EPR is a good policy in solving the growing e-waste problems. Crown Copyright © 2013. Published by Elsevier Ltd. All rights reserved.
Biofilms in Infections of the Eye
Bispo, Paulo J. M.; Haas, Wolfgang; Gilmore, Michael S.
2015-01-01
The ability to form biofilms in a variety of environments is a common trait of bacteria, and may represent one of the earliest defenses against predation. Biofilms are multicellular communities usually held together by a polymeric matrix, ranging from capsular material to cell lysate. In a structure that imposes diffusion limits, environmental microgradients arise to which individual bacteria adapt their physiologies, resulting in the gamut of physiological diversity. Additionally, the proximity of cells within the biofilm creates the opportunity for coordinated behaviors through cell–cell communication using diffusible signals, the most well documented being quorum sensing. Biofilms form on abiotic or biotic surfaces, and because of that are associated with a large proportion of human infections. Biofilm formation imposes a limitation on the uses and design of ocular devices, such as intraocular lenses, posterior contact lenses, scleral buckles, conjunctival plugs, lacrimal intubation devices and orbital implants. In the absence of abiotic materials, biofilms have been observed on the capsule, and in the corneal stroma. As the evidence for the involvement of microbial biofilms in many ocular infections has become compelling, developing new strategies to prevent their formation or to eradicate them at the site of infection, has become a priority. PMID:25806622
Fast photoresponse and high detectivity in copper indium selenide (CuIn7Se11) phototransistors
NASA Astrophysics Data System (ADS)
Ghosh, Sujoy; Patil, Prasanna D.; Wasala, Milinda; Lei, Sidong; Nolander, Andrew; Sivakumar, Pooplasingam; Vajtai, Robert; Ajayan, Pulickel; Talapatra, Saikat
2018-03-01
The fast and sensitive detection of light can lead to a variety of optoelectronics and/or photonic-based applications in fields ranging from fast optical switching devices to health and environmental monitoring systems. Although several systems based on organic and inorganic materials show high sensitivity to visible light, in general they suffer from slow response times. Here we show that phototransistors fabricated using multilayers of CuIn7Se11 exhibit response times of ~ tens of µs with responsivity (R) values > 10 AW-1 and with external quantum efficiencies reaching beyond 103 % when excited with a 658 nm wavelength laser. These devices also show high specific detectivity (D *) values of ~1012 Jones. The responsivity and detectivity exhibited by these phototransistors are at least an order of magnitude better than commercially available conventional Si-based photodetectors, coupled with response times that are orders of magnitude better than several other families of layered materials investigated so far. The properties of the CuIn7Se11 phototransistor can be further tuned and enhanced by applying a back-gate voltage. Our investigations indicate that such layered ternary compounds can potentially be used as components in opto-electronics-related applications.
AUDIS wear: a smartwatch based assistive device for ubiquitous awareness of environmental sounds.
Mielke, Matthias; Bruck, Rainer
2016-08-01
A multitude of assistive devices is available for deaf people (i.e. deaf, deafened, and hard of hearing). Besides hearing and communication aids, devices to access environmental sounds are available commercially. But the devices have two major drawbacks: 1. they are targeted at indoor environments (e.g. home or work), and 2. only specific events are supported (e.g. the doorbell or telephone). Recent research shows that important sounds can occur in all contexts and that the interests in sounds are diverse. These drawbacks can be tackled by using modern information and communication technology that enables the development of new and improved assistive devices. The smartwatch, a new computing platform in the form of a wristwatch, offers new potential for assistive technology. Its design promises a perfect integration into various different social contexts and thus blends perfectly into the user's life. Based on a smartwatch and algorithms from pattern recognition, a prototype for awareness of environmental sounds is presented here. It observes the acoustic environment of the user and detects environmental sounds. A vibration is triggered when a sound is detected and the type of sound is shown on the display. The design of the prototype was discussed with deaf people in semi-structured interviews, leading to a set of implications for the design of such a device.
Electro-optic device with gap-coupled electrode
Deri, Robert J.; Rhodes, Mark A.; Bayramian, Andrew J.; Caird, John A.; Henesian, Mark A.; Ebbers, Christopher A.
2013-08-20
An electro-optic device includes an electro-optic crystal having a predetermined thickness, a first face and a second face. The electro-optic device also includes a first electrode substrate disposed opposing the first face. The first electrode substrate includes a first substrate material having a first thickness and a first electrode coating coupled to the first substrate material. The electro-optic device further includes a second electrode substrate disposed opposing the second face. The second electrode substrate includes a second substrate material having a second thickness and a second electrode coating coupled to the second substrate material. The electro-optic device additionally includes a voltage source electrically coupled to the first electrode coating and the second electrode coating.
Solid state photosensitive devices which employ isolated photosynthetic complexes
Peumans, Peter; Forrest, Stephen R.
2009-09-22
Solid state photosensitive devices including photovoltaic devices are provided which comprise a first electrode and a second electrode in superposed relation; and at least one isolated Light Harvesting Complex (LHC) between the electrodes. Preferred photosensitive devices comprise an electron transport layer formed of a first photoconductive organic semiconductor material, adjacent to the LHC, disposed between the first electrode and the LHC; and a hole transport layer formed of a second photoconductive organic semiconductor material, adjacent to the LHC, disposed between the second electrode and the LHC. Solid state photosensitive devices of the present invention may comprise at least one additional layer of photoconductive organic semiconductor material disposed between the first electrode and the electron transport layer; and at least one additional layer of photoconductive organic semiconductor material, disposed between the second electrode and the hole transport layer. Methods of generating photocurrent are provided which comprise exposing a photovoltaic device of the present invention to light. Electronic devices are provided which comprise a solid state photosensitive device of the present invention.
International survey on neuroradiological interventional and therapeutic devices and materials.
van den Berg, René; Mayer, Thomas E
2015-12-01
A web-based survey was performed among the members of the World Federation of Interventional and Therapeutic Neuroradiology to determine the differences in availability, pricing, and performance of endovascular devices with special focus on coils, intra-arterial stroke devices, detachable balloons, and liquid embolic materials. The results of this survey show that the quality of the majority of interventional neuroradiology devices is good and compatibility issues are limited. Individual action towards suppliers is recommended to discuss the availability and pricing of devices and embolization materials. © The Author(s) 2015.
2017-07-27
The Food and Drug Administration (FDA, Agency, or we) is classifying the assayed quality control material for clinical microbiology assays into class II (special controls). The special controls that will apply to the device are identified in this order and will be part of the codified language for the assayed quality control material for clinical microbiology assays' classification. The Agency is classifying the device into class II (special controls) to provide a reasonable assurance of safety and effectiveness of the device.
Materials requirements for optical processing and computing devices
NASA Technical Reports Server (NTRS)
Tanguay, A. R., Jr.
1985-01-01
Devices for optical processing and computing systems are discussed, with emphasis on the materials requirements imposed by functional constraints. Generalized optical processing and computing systems are described in order to identify principal categories of requisite components for complete system implementation. Three principal device categories are selected for analysis in some detail: spatial light modulators, volume holographic optical elements, and bistable optical devices. The implications for optical processing and computing systems of the materials requirements identified for these device categories are described, and directions for future research are proposed.
NASA Astrophysics Data System (ADS)
Bruzzi, Mara; Pace, Emanuele; Talamonti, Cinzia
2013-12-01
The 9th edition of the International Conference on Radiation Effects on Semiconductor Materials, Detectors and Devices (RESMDD), held in Florence, at Dipartimento di Fisica ed Astronomia on October 9-12, 2012, was aimed at discussing frontier research activities in several application fields as in nuclear and particle physics, astrophysics, medical and solid-state physics. Main topics discussed in this conference are tracking performance of heavily irradiated silicon detectors, developments required for the luminosity upgrade of the Large Hadron Collider (HL-LHC), radiation effects on semiconductor materials for medical (radiotherapy dosimeters, imaging devices), astrophysics (UV, X- and γ-ray detectors) and environmental applications, microscopic defect analysis of irradiated semiconductor materials and related radiation hardening technologies. On the first day the conference hosted a short course intended to introduce fundamentals in the development of semiconductor detectors for medical applications to graduate and PhD students, post-docs and young researchers, both engineers and physicists. Directors of the School were Prof. Marta Bucciolini of the University of Florence and INFN, Italy and Dr. Carlo Civinini, INFN Firenze, Italy. Emphasis was placed on the underlying physical principles, instrument design, factors affecting performance, and applications in both the clinical and preclinical applications. The School was attended by nearly 40 students/ young researchers. We warmly thank the Directors for organizing this interesting event and the professors and researchers who gave lessons, for sharing their experience and knowledge with the students.
NASA Astrophysics Data System (ADS)
Thangavel, Ranjith; Kannan, Aravindaraj G.; Ponraj, Rubha; Thangavel, Vigneysh; Kim, Dong-Won; Lee, Yun-Sung
2018-04-01
Development of supercapacitors with high energy density and long cycle life using sustainable materials for next-generation applications is of paramount importance. The ongoing challenge is to elevate the energy density of supercapacitors on par with batteries, while upholding the power and cyclability. In addition, attaining such superior performance with green and sustainable bio-mass derived compounds is very crucial to address the rising environmental concerns. Herein, we demonstrate the use of watermelon rind, a bio-waste from watermelons, towards high energy, and ultra-stable high temperature green supercapacitors with a high-voltage ionic liquid electrolyte. Supercapacitors assembled with ultra-high surface area, hierarchically porous carbon exhibits a remarkable performance both at room temperature and at high temperature (60 °C) with maximum energy densities of ∼174 Wh kg-1 (25 °C), and 177 Wh kg-1 (60 °C) - based on active mass of both electrodes. Furthermore, an ultra-high specific power of ∼20 kW kg-1 along with an ultra-stable cycling performance with 90% retention over 150,000 cycles has been achieved even at 60 °C, outperforming supercapacitors assembled with other carbon based materials. These results demonstrate the potential to develop high-performing, green energy storage devices using eco-friendly materials for next generation electric vehicles and other advanced energy storage systems.
Prospects of e-beam evaporated molybdenum oxide as a hole transport layer for perovskite solar cells
NASA Astrophysics Data System (ADS)
Ali, F.; Khoshsirat, N.; Duffin, J. L.; Wang, H.; Ostrikov, K.; Bell, J. M.; Tesfamichael, T.
2017-09-01
Perovskite solar cells have emerged as one of the most efficient and low cost technologies for delivering of solar electricity due to their exceptional optical and electrical properties. Commercialization of the perovskite solar cells is, however, limited because of the higher cost and environmentally sensitive organic hole transport materials such as spiro-OMETAD and PEDOT:PSS. In this study, an empirical simulation was performed using the Solar Cell Capacitance Simulator software to explore the MoOx thin film as an alternative hole transport material for perovskite solar cells. In the simulation, properties of MoOx thin films deposited by the electron beam evaporation technique from high purity (99.99%) MoO3 pellets at different substrate temperatures (room temperature, 100 °C and 200 °C) were used as input parameters. The films were highly transparent (>80%) and have low surface roughness (≤2 nm) with bandgap energy ranging between 3.75 eV and 3.45 eV. Device simulation has shown that the MoOx deposited at room temperature can work in both the regular and inverted structures of the perovskite solar cell with a promising efficiency of 18.25%. Manufacturing of the full device is planned in order to utilize the MoOx as an alternative hole transport material for improved performance, good stability, and low cost of the perovskite solar cell.
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.
Homoepitaxial graphene tunnel barriers for spin transport
NASA Astrophysics Data System (ADS)
Friedman, Adam L.; van't Erve, Olaf M. J.; Robinson, Jeremy T.; Whitener, Keith E.; Jonker, Berend T.
2016-05-01
Tunnel barriers are key elements for both charge-and spin-based electronics, offering devices with reduced power consumption and new paradigms for information processing. Such devices require mating dissimilar materials, raising issues of heteroepitaxy, interface stability, and electronic states that severely complicate fabrication and compromise performance. Graphene is the perfect tunnel barrier. It is an insulator out-of-plane, possesses a defect-free, linear habit, and is impervious to interdiffusion. Nonetheless, true tunneling between two stacked graphene layers is not possible in environmental conditions usable for electronics applications. However, two stacked graphene layers can be decoupled using chemical functionalization. Here, we demonstrate that hydrogenation or fluorination of graphene can be used to create a tunnel barrier. We demonstrate successful tunneling by measuring non-linear IV curves and a weakly temperature dependent zero-bias resistance. We demonstrate lateral transport of spin currents in non-local spin-valve structures, and determine spin lifetimes with the non-local Hanle effect. We compare the results for hydrogenated and fluorinated tunnel and we discuss the possibility that ferromagnetic moments in the hydrogenated graphene tunnel barrier affect the spin transport of our devices.
Nar, Ilgın; Atsay, Armağan; Altındal, Ahmet; Hamuryudan, Esin; Koçak, Makbule B; Gül, Ahmet
2018-05-11
Bulk heterojunction (BHJ) solar cells might one day play a vital role in realizing low-cost and environmentally benign photovoltaic devices. In this work, a BHJ solar cell was designed, based on a hexadeca-substituted phthalocyanine (FcPc) with ferrocenyl linked to the phthalocyanine ring. Next, we sought to obtain more quantitative information about the usability of this newly synthesized compound as a donor material in BHJ solar cells. Thus, BHJs with the structure of indium tin oxide/poly(3,4-ethylenedioxythiophene):poly(styrenesulfonate)/FcPc:[6,6]-phenyl-C61-butyric acid methyl ester (PCBM) blend/LiF/Al were fabricated and characterized. The effect of blend ratio (0.5-2.0) on the BHJ solar cell parameters was also investigated. Interesting results were obtained in FcPc and the PCBM blend-based BHJ solar cell under optimized conditions. Our results presented here demonstrate that BHJ devices employing FcPc as a donor has great potential for the development of highly efficient non-poly(3-hexylthiophen-2,5-diyl) photovoltaic devices. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.
Integration of Nanostructures into Microsensor Devices on Whole Wafers
NASA Technical Reports Server (NTRS)
Biaggi-Labiosa, Azlin M.; Evans, Laura J.; Berger, Gordon M.; Hunter, Gary W.
2015-01-01
Chemical sensors are used in a wide variety of applications, such as environmental monitoring, fire detection, emission monitoring, and health monitoring. The fabrication of chemical sensors involving nanostructured materials holds the potential for the development of sensor systems with unique properties and improved performance. However, the fabrication and processing of nanostructures for sensor applications currently are limited in the ability to control their location on the sensor, which in turn hinders the progress for batch fabrication. This report discusses the advantages of using nanomaterials in sensor designs, some of the challenges encountered with the integration of nanostructures into microsensor / devices, and then briefly describes different methods attempted by other groups to address this issue. Finally, this report will describe how our approach for the controlled alignment of nanostructures onto a sensor platform was applied to demonstrate an approach for the mass production of sensors with nanostructures.
Fusion energy division annual progress report, period ending December 31, 1980
DOE Office of Scientific and Technical Information (OSTI.GOV)
Not Available
1981-11-01
The ORNL Program encompasses most aspects of magnetic fusion research including research on two magnetic confinement programs (tokamaks and ELMO bumpy tori); the development of the essential technologies for plasma heating, fueling, superconducting magnets, and materials; the development of diagnostics; the development of atomic physics and radiation effect data bases; the assessment of the environmental impact of magnetic fusion; the physics and engineering of present-generation devices; and the design of future devices. The integration of all of these activities into one program is a major factor in the success of each activity. An excellent example of this integration is themore » extremely successful application of neutral injection heating systems developed at ORNL to tokamaks both in the Fusion Energy Division and at Princeton Plasma Physics Laboratory (PPPL). The goal of the ORNL Fusion Program is to maintain this balance between plasma confinement, technology, and engineering activities.« less
Flexible devices: from materials, architectures to applications
NASA Astrophysics Data System (ADS)
Zou, Mingzhi; Ma, Yue; Yuan, Xin; Hu, Yi; Liu, Jie; Jin, Zhong
2018-01-01
Flexible devices, such as flexible electronic devices and flexible energy storage devices, have attracted a significant amount of attention in recent years for their potential applications in modern human lives. The development of flexible devices is moving forward rapidly, as the innovation of methods and manufacturing processes has greatly encouraged the research of flexible devices. This review focuses on advanced materials, architecture designs and abundant applications of flexible devices, and discusses the problems and challenges in current situations of flexible devices. We summarize the discovery of novel materials and the design of new architectures for improving the performance of flexible devices. Finally, we introduce the applications of flexible devices as key components in real life. Project supported by the National Key R&D Program of China (Nos. 2017YFA0208200, 2016YFB0700600, 2015CB659300), the National Natural Science Foundation of China (Nos. 21403105, 21573108), and the Fundamental Research Funds for the Central Universities (No. 020514380107).
Advanced refractory metals and composites for extraterrestrial power systems
NASA Technical Reports Server (NTRS)
Titran, R. H.; Grobstein, Toni L.
1990-01-01
Concepts for future space power systems include nuclear and focused solar heat sources coupled to static and dynamic power-conversion devices; such systems must be designed for service lives as long as 30 years, despite service temperatures of the order of 1600 K. Materials are a critical technology-development factor in such aspects of these systems as reactor fuel containment, environmental protection, power management, and thermal management. Attention is given to the prospective performance of such refractory metals as Nb, W, and Mo alloys, W fiber-reinforced Nb-matrix composites, and HfC precipitate-strengthened W-Re alloys.
Ergonomic material-handling device
Barsnick, Lance E.; Zalk, David M.; Perry, Catherine M.; Biggs, Terry; Tageson, Robert E.
2004-08-24
A hand-held ergonomic material-handling device capable of moving heavy objects, such as large waste containers and other large objects requiring mechanical assistance. The ergonomic material-handling device can be used with neutral postures of the back, shoulders, wrists and knees, thereby reducing potential injury to the user. The device involves two key features: 1) gives the user the ability to adjust the height of the handles of the device to ergonomically fit the needs of the user's back, wrists and shoulders; and 2) has a rounded handlebar shape, as well as the size and configuration of the handles which keep the user's wrists in a neutral posture during manipulation of the device.
Wehrman, Matthew D; Milstrey, Melissa J; Lindberg, Seth; Schultz, Kelly M
2018-04-19
The microstructure of soft matter directly impacts macroscopic rheological properties and can be changed by factors including colloidal rearrangement during previous phase changes and applied shear. To determine the extent of these changes, we have developed a microfluidic device that enables repeated phase transitions induced by exchange of the surrounding fluid and microrheological characterization while limiting shear on the sample. This technique is µ 2 rheology, the combination of microfluidics and microrheology. The microfluidic device is a two-layer design with symmetric inlet streams entering a sample chamber that traps the gel sample in place during fluid exchange. Suction can be applied far away from the sample chamber to pull fluids into the sample chamber. Material rheological properties are characterized using multiple particle tracking microrheology (MPT). In MPT, fluorescent probe particles are embedded into the material and the Brownian motion of the probes is recorded using video microscopy. The movement of the particles is tracked and the mean-squared displacement (MSD) is calculated. The MSD is related to macroscopic rheological properties, using the Generalized Stokes-Einstein Relation. The phase of the material is identified by comparison to the critical relaxation exponent, determined using time-cure superposition. Measurements of a fibrous colloidal gel illustrate the utility of the technique. This gel has a delicate structure that can be irreversibly changed when shear is applied. µ 2 rheology data shows that the material repeatedly equilibrates to the same rheological properties after each phase transition, indicating that phase transitions do not play a role in microstructural changes. To determine the role of shear, samples can be sheared prior to injection into our microfluidic device. µ 2 rheology is a widely applicable technique for the characterization of soft matter enabling the determination of rheological properties of delicate microstructures in a single sample during phase transitions in response to repeated changes in the surrounding environmental conditions.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 10 Energy 1 2010-01-01 2010-01-01 false Manufacture and distribution of sources or devices... SPECIFIC DOMESTIC LICENSES TO MANUFACTURE OR TRANSFER CERTAIN ITEMS CONTAINING BYPRODUCT MATERIAL Generally Licensed Items § 32.74 Manufacture and distribution of sources or devices containing byproduct material for...
UV-Assisted Reduction in BBL/Graphene Nanocomposite for Micropatterning
2014-05-27
properties has motivated the development of new composite materials for nanoelectronics, supercapacitors , batteries, photovoltaics, and related devices. The...for nanoelectronics, supercapacitors , batteries, photovoltaics, and related devices. The conjugated ladder polymer poly(benzimidazobenzo-phenanthroline...materials, is motivated by the development of new composite materials for nanoelectronics, supercapacitors , batteries, photovoltaics, and related devices
49 CFR 392.33 - Obscured lamps or reflective devices/material.
Code of Federal Regulations, 2013 CFR
2013-10-01
... 49 Transportation 5 2013-10-01 2013-10-01 false Obscured lamps or reflective devices/material. 392... REGULATIONS DRIVING OF COMMERCIAL MOTOR VEHICLES Use of Lighted Lamps and Reflectors § 392.33 Obscured lamps or reflective devices/material. (a) No commercial motor vehicle shall be driven when any of the lamps...
49 CFR 392.33 - Obscured lamps or reflective devices/material.
Code of Federal Regulations, 2012 CFR
2012-10-01
... 49 Transportation 5 2012-10-01 2012-10-01 false Obscured lamps or reflective devices/material. 392... REGULATIONS DRIVING OF COMMERCIAL MOTOR VEHICLES Use of Lighted Lamps and Reflectors § 392.33 Obscured lamps or reflective devices/material. (a) No commercial motor vehicle shall be driven when any of the lamps...
49 CFR 392.33 - Obscured lamps or reflective devices/material.
Code of Federal Regulations, 2014 CFR
2014-10-01
... 49 Transportation 5 2014-10-01 2014-10-01 false Obscured lamps or reflective devices/material. 392... REGULATIONS DRIVING OF COMMERCIAL MOTOR VEHICLES Use of Lighted Lamps and Reflectors § 392.33 Obscured lamps or reflective devices/material. (a) No commercial motor vehicle shall be driven when any of the lamps...
49 CFR 392.33 - Obscured lamps or reflective devices/material.
Code of Federal Regulations, 2011 CFR
2011-10-01
... 49 Transportation 5 2011-10-01 2011-10-01 false Obscured lamps or reflective devices/material. 392... REGULATIONS DRIVING OF COMMERCIAL MOTOR VEHICLES Use of Lighted Lamps and Reflectors § 392.33 Obscured lamps or reflective devices/material. (a) No commercial motor vehicle shall be driven when any of the lamps...
Sterilization and reprocessing of materials and medical devices--reusability.
Jayabalan, M
1995-07-01
Problems associated with reprocessing of disposable medical devices such as hemodialysers with resterilization for reuse and changes in material properties with resterilization of polymeric (PVC, polypropylene, polyester, polycarbonate) materials intended for development of disposable devices are reviewed. Reprocessing of hospital supplies, polystyrene microtiter plate and angiographic catheter for reuse is also discussed.
Code of Federal Regulations, 2012 CFR
2012-01-01
... pertinent to an evaluation of its radiation safety, including: (i) The byproduct material contained, its... maintain its integrity under stresses likely to be encountered in normal use and accidents; (iv) For devices containing byproduct material, the radiation profile of a prototype device; (v) Details of quality...
Code of Federal Regulations, 2011 CFR
2011-01-01
... pertinent to an evaluation of its radiation safety, including: (i) The byproduct material contained, its... maintain its integrity under stresses likely to be encountered in normal use and accidents; (iv) For devices containing byproduct material, the radiation profile of a prototype device; (v) Details of quality...
Borton, Lindsey K; Coleman, Kelly P
2018-06-14
Pyrogenicity presents a challenge to clinicians, medical device manufactures, and regulators. A febrile response may be caused by endotoxin contamination, microbial components other than endotoxin, or chemical agents that generate a material-mediated pyrogenic response. While test methods for the assessment of endotoxin contamination and some microbial components other than endotoxin are well-established, material-mediated pyrogens remain elusively undefined. This review presents the findings of literature searches conducted to identify material-mediated pyrogens associated with medical devices. The in vivo rabbit pyrogen test (RPT) is considered to be the "gold standard" for medical device pyrogenicity testing, despite the fact that few medical device-derived material-mediated pyrogens are known. In line with global efforts to reduce the use of research animals, an in vitro monocyte activation test (MAT) has the potential to replace the RPT. The MAT is used to detect substances that activate human monocytes to release cytokines. This review will also describe the potential opportunities and challenges associated with MAT adoption for the detection of material-mediated pyrogens in medical device testing.
3D printing functional materials and devices (Conference Presentation)
NASA Astrophysics Data System (ADS)
McAlpine, Michael C.
2017-05-01
The development of methods for interfacing high performance functional devices with biology could impact regenerative medicine, smart prosthetics, and human-machine interfaces. Indeed, the ability to three-dimensionally interweave biological and functional materials could enable the creation of devices possessing unique geometries, properties, and functionalities. Yet, most high quality functional materials are two dimensional, hard and brittle, and require high crystallization temperatures for maximal performance. These properties render the corresponding devices incompatible with biology, which is three-dimensional, soft, stretchable, and temperature sensitive. We overcome these dichotomies by: 1) using 3D printing and scanning for customized, interwoven, anatomically accurate device architectures; 2) employing nanotechnology as an enabling route for overcoming mechanical discrepancies while retaining high performance; and 3) 3D printing a range of soft and nanoscale materials to enable the integration of a diverse palette of high quality functional nanomaterials with biology. 3D printing is a multi-scale platform, allowing for the incorporation of functional nanoscale inks, the printing of microscale features, and ultimately the creation of macroscale devices. This three-dimensional blending of functional materials and `living' platforms may enable next-generation 3D printed devices.
Electrostatic testing of thin plastic materials
NASA Technical Reports Server (NTRS)
Skinner, S. Ballou
1988-01-01
Ten thin plastic materials (Velostat, RCAS 1200, Llumalloy, Herculite 80, RCAS 2400, Wrightlon 7000, PVC, Aclar 22A, Mylar, and Polyethylene) were tested for electrostatic properties by four different devices: (1) The static decay meter, (2) the manual triboelectric testing device, (3) the robotic triboelectric testing device, and (4) the resistivity measurement adapter device. The static decay meter measured the electrostatic decay rates in accordance with the Federal Test Method Standard 101B, Method 4046. The manual and the robotic triboelectric devices measured the triboelectric generated peak voltages and the five-second decay voltages in accordance with the criteria for acceptance standards at Kennedy Space Center. The resistivity measurement adapter measured the surface resistivity of each material. An analysis was made to correlate the data among the four testing devices. For the material tested the pass/fail results were compared for the 4046 method and the triboelectric testing devices. For the limited number of materials tested, the relationship between decay rate and surface resistivity was investigated as well as the relationship between triboelectric peak voltage and surface resistivity.
75 FR 43979 - Massachusetts Marine Sanitation Device Standard-Notice of Determination
Federal Register 2010, 2011, 2012, 2013, 2014
2010-07-27
... England Region, Office of Ecosystem Protection, Oceans and Coastal Protection Unit, Five Post Office... ENVIRONMENTAL PROTECTION AGENCY [EPA-R01-OW-2010-0318, FRL-9180-3] Massachusetts Marine Sanitation Device Standard--Notice of Determination AGENCY: Environmental Protection Agency (EPA). ACTION: Notice of...
76 FR 39395 - Massachusetts Marine Sanitation Device Standard-Notice of Determination
Federal Register 2010, 2011, 2012, 2013, 2014
2011-07-06
... England Region, Office of Ecosystem Protection, Oceans and Coastal Protection Unit, Five Post Office... ENVIRONMENTAL PROTECTION AGENCY [EPA-R01-OW-2011-0364, FRL-9430-1] Massachusetts Marine Sanitation Device Standard--Notice of Determination AGENCY: Environmental Protection Agency (EPA). ACTION: Notice of...
75 FR 38516 - Massachusetts Marine Sanitation Device Standard-Notice of Determination
Federal Register 2010, 2011, 2012, 2013, 2014
2010-07-02
... England Region, Office of Ecosystem Protection, Oceans and Coastal Protection Unit, Five Post Office... ENVIRONMENTAL PROTECTION AGENCY [EPA-R01-OW-2010-0316, FRL-9170-4] Massachusetts Marine Sanitation Device Standard--Notice of Determination AGENCY: Environmental Protection Agency (EPA). ACTION: Notice of...
75 FR 4379 - Maine Marine Sanitation Device Standard-Notice of Determination
Federal Register 2010, 2011, 2012, 2013, 2014
2010-01-27
... Protection Agency--New England Region, Office of Ecosystem Protection, Coastal and Oceans Protection Unit... ENVIRONMENTAL PROTECTION AGENCY [EPA-R01-OW-2009-0304, FRL-9106-3] Maine Marine Sanitation Device Standard--Notice of Determination AGENCY: Environmental Protection Agency (EPA). ACTION: Notice of...
Paper-based analytical devices for environmental analysis.
Meredith, Nathan A; Quinn, Casey; Cate, David M; Reilly, Thomas H; Volckens, John; Henry, Charles S
2016-03-21
The field of paper-based microfluidics has experienced rapid growth over the past decade. Microfluidic paper-based analytical devices (μPADs), originally developed for point-of-care medical diagnostics in resource-limited settings, are now being applied in new areas, such as environmental analyses. Low-cost paper sensors show great promise for on-site environmental analysis; the theme of ongoing research complements existing instrumental techniques by providing high spatial and temporal resolution for environmental monitoring. This review highlights recent applications of μPADs for environmental analysis along with technical advances that may enable μPADs to be more widely implemented in field testing.
Liu, Ming; Zhang, Xiang
2018-01-23
This disclosure provides systems, methods, and apparatus related to catalytic devices. In one aspect, a device includes a substrate, an electrically insulating layer disposed on the substrate, a layer of material disposed on the electrically insulating layer, and a catalyst disposed on the layer of material. The substrate comprises an electrically conductive material. The substrate and the layer of material are electrically coupled to one another and configured to have a voltage applied across them.
Goldfuss, G.T.
1975-09-16
This invention relates to a device for sensing the level of a liquid while preventing the deposition and accumulation of materials on the exterior surfaces thereof. Two dissimilar metal wires are enclosed within an electrical insulating material, the wires being joined together at one end to form a thermocouple junction outside the insulating material. Heating means is disposed within the electrical insulating material and maintains the device at a temperature substantially greater than that of the environment surrounding the device, the heating means being electrically insulated from the two dissimilar thermocouple wires. In addition, a metal sheath surrounds and contacts both the electrical insulating material and the thermocouple junction. Electrical connections are provided for connecting the heating means with a power source and for connecting the thermocouple wires with a device for sensing the electrical potential across the thermocouple junction. (auth)
The 2016 oxide electronic materials and oxide interfaces roadmap
NASA Astrophysics Data System (ADS)
Lorenz, M.; Ramachandra Rao, M. S.; Venkatesan, T.; Fortunato, E.; Barquinha, P.; Branquinho, R.; Salgueiro, D.; Martins, R.; Carlos, E.; Liu, A.; Shan, F. K.; Grundmann, M.; Boschker, H.; Mukherjee, J.; Priyadarshini, M.; DasGupta, N.; Rogers, D. J.; Teherani, F. H.; Sandana, E. V.; Bove, P.; Rietwyk, K.; Zaban, A.; Veziridis, A.; Weidenkaff, A.; Muralidhar, M.; Murakami, M.; Abel, S.; Fompeyrine, J.; Zuniga-Perez, J.; Ramesh, R.; Spaldin, N. A.; Ostanin, S.; Borisov, V.; Mertig, I.; Lazenka, V.; Srinivasan, G.; Prellier, W.; Uchida, M.; Kawasaki, M.; Pentcheva, R.; Gegenwart, P.; Miletto Granozio, F.; Fontcuberta, J.; Pryds, N.
2016-11-01
Oxide electronic materials provide a plethora of possible applications and offer ample opportunity for scientists to probe into some of the exciting and intriguing phenomena exhibited by oxide systems and oxide interfaces. In addition to the already diverse spectrum of properties, the nanoscale form of oxides provides a new dimension of hitherto unknown phenomena due to the increased surface-to-volume ratio. Oxide electronic materials are becoming increasingly important in a wide range of applications including transparent electronics, optoelectronics, magnetoelectronics, photonics, spintronics, thermoelectrics, piezoelectrics, power harvesting, hydrogen storage and environmental waste management. Synthesis and fabrication of these materials, as well as processing into particular device structures to suit a specific application is still a challenge. Further, characterization of these materials to understand the tunability of their properties and the novel properties that evolve due to their nanostructured nature is another facet of the challenge. The research related to the oxide electronic field is at an impressionable stage, and this has motivated us to contribute with a roadmap on ‘oxide electronic materials and oxide interfaces’. This roadmap envisages the potential applications of oxide materials in cutting edge technologies and focuses on the necessary advances required to implement these materials, including both conventional and novel techniques for the synthesis, characterization, processing and fabrication of nanostructured oxides and oxide-based devices. The contents of this roadmap will highlight the functional and correlated properties of oxides in bulk, nano, thin film, multilayer and heterostructure forms, as well as the theoretical considerations behind both present and future applications in many technologically important areas as pointed out by Venkatesan. The contributions in this roadmap span several thematic groups which are represented by the following authors: novel field effect transistors and bipolar devices by Fortunato, Grundmann, Boschker, Rao, and Rogers; energy conversion and saving by Zaban, Weidenkaff, and Murakami; new opportunities of photonics by Fompeyrine, and Zuniga-Perez; multiferroic materials including novel phenomena by Ramesh, Spaldin, Mertig, Lorenz, Srinivasan, and Prellier; and concepts for topological oxide electronics by Kawasaki, Pentcheva, and Gegenwart. Finally, Miletto Granozio presents the European action ‘towards oxide-based electronics’ which develops an oxide electronics roadmap with emphasis on future nonvolatile memories and the required technologies. In summary, we do hope that this oxide roadmap appears as an interesting up-to-date snapshot on one of the most exciting and active areas of solid state physics, materials science, and chemistry, which even after many years of very successful development shows in short intervals novel insights and achievements. Guest editors: M S Ramachandra Rao and Michael Lorenz
DOE Office of Scientific and Technical Information (OSTI.GOV)
Aguiar, Jeffery A.; Wozny, Sarah; Alkurd, Nooraldeen R.
Perovskite-based solar cells are one of the emerging candidates for radically lower cost photovoltaics. Herein, we report on the synthesis and crystallization of organic-inorganic formamidinium lead triiodide perovskite films under controlled atmospheric and environmental conditions. Using in situ (scanning) transmission electron microscopy, we make observations of the crystallization process of these materials in nitrogen and oxygen gas with and without the presence of water vapor. Complementary planar samples were also fabricated in the presence of water vapor and characterized by in situ X-ray diffraction. Direct observations of the material structure and final morphology indicate that the exposure to water vapormore » results in a porous film that is metastable, regardless of the presence of argon, nitrogen, or oxygen. However, the optimal crystallization temperature of 175 degrees C is unperturbed across conditions. Rapid modulation about the annealing temperature of 175 degrees C in +/-25 degrees C steps (150-200 degrees C) promotes crystallization and significantly improves the film morphology by overcoming the presence of impregnated water trapped in the material. Following this processing protocol, we demonstrate substantial growth to micron-size grains via observation inside of an environmentally controlled transmission electron microscope. Adapting this insight from our in situ microscopy, we are able to provide an informed materials protocol to control the structure and morphology of these organic-inorganic semiconductors, which is readily applicable to benchtop device growth strategies.« less
DOE Office of Scientific and Technical Information (OSTI.GOV)
Aguiar, Jeffery A.; Wozny, Sarah; Alkurd, Nooraldeen R.
Perovskite-based solar cells are one of the emerging candidates for radically lower cost photovoltaics. Herein, we report on the synthesis and crystallization of organic-inorganic formamidinium lead triiodide perovskite films under controlled atmospheric and environmental conditions. Using in situ (scanning) transmission electron microscopy, we make observations of the crystallization process of these materials in nitrogen and oxygen gas with and without the presence of water vapor. Complementary planar samples were also fabricated in the presence of water vapor and characterized by in situ X-ray diffraction. Direct observations of the material structure and final morphology indicate that the exposure to water vapormore » results in a porous film that is metastable, regardless of the presence of argon, nitrogen, or oxygen. However, the optimal crystallization temperature of 175 °C is unperturbed across conditions. Rapid modulation about the annealing temperature of 175 °C in ±25 °C steps (150-200 °C) promotes crystallization and significantly improves the film morphology by overcoming the presence of impregnated water trapped in the material. Following this processing protocol, we demonstrate substantial growth to micron-size grains via observation inside of an environmentally controlled transmission electron microscope. Adapting this insight from our in situ microscopy, we are able to provide an informed materials protocol to control the structure and morphology of these organic-inorganic semiconductors, which is readily applicable to benchtop device growth strategies.« less
HBCU/MI: 3D Formable RF Materials and Devices
2016-08-01
SECURITY CLASSIFICATION OF: The aim of this project was to explore 3D printing for RF/microwave circuits and devices. The research produced several... 3D printed microwave filters, a 3D wifi radio circuit, and new materials for 3D printed electromagnetic devices. The research demonstrates that 3D ...journals: Final Report: HBCU/MI: 3D Formable RF Materials and Devices Report Title The aim of this project was to explore 3D printing for RF/microwave
Reading disc-based bioassays with standard computer drives.
Yu, Hua-Zhong; Li, Yunchao; Ou, Lily M-L
2013-02-19
Traditional methods of disease diagnosis are both time-consuming and labor-intensive, and many tests require expensive instrumentation and trained professionals, which restricts their use to biomedical laboratories. Because patients can wait several days (even weeks) for the results, the consequences of delayed treatment could be disastrous. Therefore, affordable and simple point-of-care (POC) biosensor devices could fill a diagnostic niche in the clinic or even at home, as personal glucose meters do for diabetics. These devices would allow patients to check their own health conditions and enable physicians to make prompt treatment decisions, which could improve the chances for rapid recovery and cure. Compact discs (CDs) provide inexpensive substrate materials for the preparation of microarray biochips, and conventional computer drives/disc players can be adapted as precise optical reading devices for signal processing. Researchers can employ the polycarbonate (PC) base of a CD as an alternative substrate to glass slides or silicon wafers for the preparation of microanalytical devices. Using the characteristic optical phenomena occurring on the metal layer of a CD, researchers can develop biosensors based on advanced spectroscopic readout (interferometry or surface plasmon resonance). If researchers integrate microfluidic functions with CD mechanics, they can control fluid transfer through the spinning motion of the disc, leading to "lab-on-a-CD" devices. Over the last decade, our laboratory has focused on the construction of POC biosensor devices from off-the-shelf CDs or DVDs and standard computer drives. Besides the initial studies of the suitability of CDs for surface and materials chemistry research (fabrication of self-assembled monolayers and oxide nanostructures), we have demonstrated that an ordinary optical drive, without modification of either the hardware or the software driver, can function as the signal transducing element for reading disc-based bioassays quantitatively. In this Account, we first provide a brief introduction to CD-related materials chemistry and microfluidics research. Then we describe the mild chemistry developed in our laboratory for the preparation of computer-readable biomolecular screening assays: photochemical activation of the polycarbonate (PC) disc surface and immobilization and delivery of probe and target biomolecules. We thoroughly discuss the analysis of the molecular recognition events: researchers can "read" these devices quantitatively with an unmodified optical drive of any personal computer. Finally, and critically, we illustrate our digitized molecular diagnosis approach with three trial systems: DNA hybridization, antibody-antigen binding, and ultrasensitive lead detection with a DNAzyme assay. These examples demonstrate the broad potential of this new analytical/diagnostic tool for medical screening, on-site food/water safety testing, and remote environmental monitoring.
LUMOS--A Sensitive and Reliable Optode System for Measuring Dissolved Oxygen in the Nanomolar Range.
Lehner, Philipp; Larndorfer, Christoph; Garcia-Robledo, Emilio; Larsen, Morten; Borisov, Sergey M; Revsbech, Niels-Peter; Glud, Ronnie N; Canfield, Donald E; Klimant, Ingo
2015-01-01
Most commercially available optical oxygen sensors target the measuring range of 300 to 2 μmol L-1. However these are not suitable for investigating the nanomolar range which is relevant for many important environmental situations. We therefore developed a miniaturized phase fluorimeter based measurement system called the LUMOS (Luminescence Measuring Oxygen Sensor). It consists of a readout device and specialized "sensing chemistry" that relies on commercially available components. The sensor material is based on palladium(II)-5,10,15,20-tetrakis-(2,3,4,5,6-pentafluorphenyl)-porphyrin embedded in a Hyflon AD 60 polymer matrix and has a KSV of 6.25 x 10-3 ppmv-1. The applicable measurement range is from 1000 nM down to a detection limit of 0.5 nM. A second sensor material based on the platinum(II) analogue of the porphyrin is spectrally compatible with the readout device and has a measurement range of 20 μM down to 10 nM. The LUMOS device is a dedicated system optimized for a high signal to noise ratio, but in principle any phase flourimeter can be adapted to act as a readout device for the highly sensitive and robust sensing chemistry. Vise versa, the LUMOS fluorimeter can be used for read out of less sensitive optical oxygen sensors based on the same or similar indicator dyes, for example for monitoring oxygen at physiological conditions. The presented sensor system exhibits lower noise, higher resolution and higher sensitivity than the electrochemical STOX sensor previously used to measure nanomolar oxygen concentrations. Oxygen contamination in common sample containers has been investigated and microbial or enzymatic oxygen consumption at nanomolar concentrations is presented.
NASA Astrophysics Data System (ADS)
Penmetcha, Anirudh Raju
Significant efficiency increases are being made for bulk heterojunction organic photovoltaic prototype devices with world records at 11%. However the chlorinated solvents most frequently used in prototype manufacture would cause local health and safety concerns or large scale environmental pollution upon expansion of these techniques for commercialization. Moreover, research to bridge prototype and large-scale production of these solar cells is still in its infancy. Most prototype devices are made in inert glove box environments using spin-coating. There is a need to develop a non-toxic ink and incorporate it into a material deposition system that can be used in mass production. In this thesis, P3HT:PCBM organic photovoltaic devices were fabricated with the help of inkjet printing. P3HT:PCBM blends were dissolved in organic solvent systems, and this solution was used as the ink for the printer. The "coffee-ring effect" as well as the effect of inkjet printing parameters on film formation were highlighted - thus the inkjet printing method was validated as a stepping stone between lab-scale production of OPVs and large-scale roll-to-roll manufacturing. To address the need of a non-toxic ink, P3HT:PCBM blends were then dispersed in water, using the miniemulsion method. The nanoparticles were characterized for their size, as well as the blending between the P3HT and PCBM within the nanoparticle. These dispersions were then converted into inks. Finally, these nanoparticle inks were inkjet-printed to fabricate OPV devices. Based on the results obtained here, tentative "next steps" have been outlined in order to improve upon this research work, in the future.
LUMOS - A Sensitive and Reliable Optode System for Measuring Dissolved Oxygen in the Nanomolar Range
Lehner, Philipp; Larndorfer, Christoph; Garcia-Robledo, Emilio; Larsen, Morten; Borisov, Sergey M.; Revsbech, Niels-Peter; Glud, Ronnie N.; Canfield, Donald E.; Klimant, Ingo
2015-01-01
Most commercially available optical oxygen sensors target the measuring range of 300 to 2 μmol L-1. However these are not suitable for investigating the nanomolar range which is relevant for many important environmental situations. We therefore developed a miniaturized phase fluorimeter based measurement system called the LUMOS (Luminescence Measuring Oxygen Sensor). It consists of a readout device and specialized “sensing chemistry” that relies on commercially available components. The sensor material is based on palladium(II)-5,10,15,20-tetrakis-(2,3,4,5,6-pentafluorphenyl)-porphyrin embedded in a Hyflon AD 60 polymer matrix and has a KSV of 6.25 x 10-3 ppmv-1. The applicable measurement range is from 1000 nM down to a detection limit of 0.5 nM. A second sensor material based on the platinum(II) analogue of the porphyrin is spectrally compatible with the readout device and has a measurement range of 20 μM down to 10 nM. The LUMOS device is a dedicated system optimized for a high signal to noise ratio, but in principle any phase flourimeter can be adapted to act as a readout device for the highly sensitive and robust sensing chemistry. Vise versa, the LUMOS fluorimeter can be used for read out of less sensitive optical oxygen sensors based on the same or similar indicator dyes, for example for monitoring oxygen at physiological conditions. The presented sensor system exhibits lower noise, higher resolution and higher sensitivity than the electrochemical STOX sensor previously used to measure nanomolar oxygen concentrations. Oxygen contamination in common sample containers has been investigated and microbial or enzymatic oxygen consumption at nanomolar concentrations is presented. PMID:26029920
Crosslinked polymeric dielectric materials and electronic devices incorporating same
NASA Technical Reports Server (NTRS)
Facchetti, Antonio (Inventor); Suh, legal representative, Nae-Jeong (Inventor); Marks, Tobin J. (Inventor); Choi, Hyuk-Jin (Inventor); Wang, Zhiming (Inventor)
2012-01-01
Solution-processable dielectric materials are provided, along with precursor compositions and processes for preparing the same. Composites and electronic devices including the dielectric materials also are provided.
Electrodes mitigating effects of defects in organic electronic devices
Heller, Christian Maria Anton [Albany, NY
2008-05-06
A compound electrode for organic electronic devices comprises a thin first layer of a first electrically conducting material and a second electrically conducting material disposed on the first layer. In one embodiment, the second electrically conducting material is formed into a plurality of elongated members. In another embodiment, the second material is formed into a second layer. The elongated members or the second layer has a thickness greater than that of the first layer. The second layer is separated from the first layer by a conducting material having conductivity less than at least the material of the first layer. The compound electrode is capable of mitigating adverse effects of defects, such as short circuits, in the construction of the organic electronic devices, and can be included in light-emitting or photovoltaic devices.
Savina, Irina N.; Ingavle, Ganesh C.; Cundy, Andrew B.; Mikhalovsky, Sergey V.
2016-01-01
The development of bulk, three-dimensional (3D), macroporous polymers with high permeability, large surface area and large volume is highly desirable for a range of applications in the biomedical, biotechnological and environmental areas. The experimental techniques currently used are limited to the production of small size and volume cryogel material. In this work we propose a novel, versatile, simple and reproducible method for the synthesis of large volume porous polymer hydrogels by cryogelation. By controlling the freezing process of the reagent/polymer solution, large-scale 3D macroporous gels with wide interconnected pores (up to 200 μm in diameter) and large accessible surface area have been synthesized. For the first time, macroporous gels (of up to 400 ml bulk volume) with controlled porous structure were manufactured, with potential for scale up to much larger gel dimensions. This method can be used for production of novel 3D multi-component macroporous composite materials with a uniform distribution of embedded particles. The proposed method provides better control of freezing conditions and thus overcomes existing drawbacks limiting production of large gel-based devices and matrices. The proposed method could serve as a new design concept for functional 3D macroporous gels and composites preparation for biomedical, biotechnological and environmental applications. PMID:26883390
Investigation on micromachining technologies for the realization of LTCC devices and systems
NASA Astrophysics Data System (ADS)
Haas, T.; Zeilmann, C.; Bittner, A.; Schmid, U.
2011-06-01
Low temperature co-fired ceramics (LTCC) has established as a widespread platform for advanced functional ceramic devices in different applications, such as in the space and aviation sector, for micro machined sensors as well as in micro fluidics. This is due to high reliability, excellent physical properties, especially in the high frequency range, and the possibility to integrate passive components in the monolithic LTCC body, offering the potential for a high degree of miniaturisation. However, for further improvement of this technology and for an ongoing increase of the integration level, the realization of miniaturized structures is of utmost importance. Therefore, novel techniques for micro-machining are required providing channel structures and cavities inside the glass-ceramic body, enabling for further application scenarios. Those techniques are punching, laser cutting and embossing. One of the most limitations of LTCC is the poor thermal conductivity. Hence, the possibility to integrate channels enables innovative active cooling approaches using fluidic media for heat critical devices. Doing so, a by far better cooling effect can be achieved than by passive devices as heat spreaders or heat sinks. Furthermore, the realization of mechanic devices as integrated pressure sensors for operation under harsh environmental conditions can be realized by integrating the membrane directly into the ceramic body. Finally, for high power devices substantial improvement can be provided by filling those channel structures with electrical conductive material, so that the resistivity can be decreased drastically without affecting the topography of the ceramics.
Research Spotlight: The next big thing is actually small.
Garcia, Carlos D
2012-07-01
Recent developments in materials, surface modifications, separation schemes, detection systems and associated instrumentation have allowed significant advances in the performance of lab-on-a-chip devices. These devices, also referred to as micro total analysis systems (µTAS), offer great versatility, high throughput, short analysis time, low cost and, more importantly, performance that is comparable to standard bench-top instrumentation. To date, µTAS have demonstrated advantages in a significant number of fields including biochemical, pharmaceutical, military and environmental. Perhaps most importantly, µTAS represent excellent platforms to introduce students to microfabrication and nanotechnology, bridging chemistry with other fields, such as engineering and biology, enabling the integration of various skills and curricular concepts. Considering the advantages of the technology and the potential impact to society, our research program aims to address the need for simpler, more affordable, faster and portable devices to measure biologically active compounds. Specifically, the program is focused on the development and characterization of a series of novel strategies towards the realization of integrated microanalytical devices. One key aspect of our research projects is that the developed analytical strategies must be compatible with each other; therefore, enabling their use in integrated devices. The program combines spectroscopy, surface chemistry, capillary electrophoresis, electrochemical detection and nanomaterials. This article discusses some of the most recent results obtained in two main areas of emphasis: capillary electrophoresis, microchip-capillary electrophoresis, electrochemical detection and interaction of proteins with nanomaterials.
Wäger, P A; Hischier, R; Eugster, M
2011-04-15
While Waste Electrical and Electronic Equipment (WEEE) collection and recovery have significantly gained in importance all over Europe in the last 15years, comprehensive studies assessing the environmental loads and benefits of these systems still are not common. In this paper we present the results of a combined material flow analysis and life cycle assessment study, which aimed to calculate the overall environmental impacts of collection, pre-processing and end-processing for the existing Swiss WEEE collection and recovery systems, as well as of incineration and landfilling scenarios, in which the same amount of WEEE is either incinerated in a an MSWI plant or landfilled. According to the calculations based on the material flow data for the year 2009 and a new version of the ecoinvent life cycle inventory database (ecoinvent v2.01), collection, recovery and disposal result in significantly lower environmental impacts per t of WEEE for midpoint indicators such as global warming or ozone depletion and the endpoint indicator Eco-Indicator '99 points. A comparison between the environmental impacts of the WEEE recovery scenarios 2009 and 2004, both calculated with ecoinvent v2.01 data, shows that the impacts per t of WEEE in 2009 were slightly lower. This appears to be mainly due to the changes in the treatment of plastics (more recycling, less incineration). Compared to the overall environmental impacts of the recovery scenario 2004 obtained with an old version of ecoinvent (ecoinvent v1.1), the calculation with ecoinvent v2.01 results in an increase of the impacts by about 20%, which is primarily the consequence of a more adequate modeling of several WEEE fractions (e.g. metals, cables or CRT devices). In view of a further increase of the environmental benefits associated with the Swiss WEEE collection and recovery systems, the recovery of geochemically scarce metals should be further investigated, in particular. Copyright © 2011 Elsevier B.V. All rights reserved.
Micro-Devices Using Resistance Change Materials (MODERN Materials)
2014-03-07
subcontractors/co-PIs on this program Taskl; subtaskl Design of micro-devices based on resistance change materials Taskl; subtask2 Fabrication and process...currently valid OMB control number. PLEASE DO NOT RETURN YOUR FORM TO THE ABOVE ADDRESS. 1. REPORT DATE ( DD -MM-YYYY) 07/03/2014 2. REPORT TYPE Final...Technical Report 3. DATES COVERED (From Jan 2013-May 2014 To) 4. TITLE AND SUBTITLE Micro Devices based on Resistance Change Materials 5a
Ternary Au/ZnO/rGO nanocomposites electrodes for high performance electrochemical storage devices
NASA Astrophysics Data System (ADS)
Chaudhary, Manchal; Doong, Ruey-an; Kumar, Nagesh; Tseng, Tseung Yuen
2017-10-01
The combination of metal and metal oxide nanoparticles with reduced graphene oxides (rGO) is an active electrode material for electrochemical storage devices. Herein, we have, for the first time, reported the fabrication of ternary Au/ZnO/rGO nanocomposites by using a rapid and environmentally friendly microwave-assisted hydrothermal method for high performance supercapacitor applications. The ZnO/rGO provides excellent electrical conductivity and good macro/mesopore structures, which can facilitate the rapid electrons and ions transport. The Au nanoparticles with particle sizes of 7-12 nm are homogeneously distributed onto the ZnO/rGO surface to enhance the electrochemical performance by retaining the capacitance at high current density. The Au/ZnO/rGO nanocomposites, prepared with the optimized rGO amount of 100 mg exhibit a high specific capacitance of 875 and 424 F g-1 at current densities of 1 and 20 A g-1, respectively, in 2 M KOH. In addition, the energy and power densities of ternary Au/ZnO/rGO can be up to 17.6-36.5 Wh kg-1 and 0.27-5.42 kW kg-1, respectively. Results obtained in this study clearly demonstrate the excellence of ternary Au/ZnO/rGO nanocomposites as the active electrode materials for electrochemical pseudocapacitor performance and can open an avenue to fabricate metal/metal oxide/rGO nanocomposites for electrochemical storage devices with both high energy and power densities.
Method of producing strained-layer semiconductor devices via subsurface-patterning
Dodson, Brian W.
1993-01-01
A method is described for patterning subsurface features in a semiconductor device, wherein the semiconductor device includes an internal strained layer. The method comprises creating a pattern of semiconductor material over the semiconductor device, the semiconductor material having a predetermined thickness which stabilizes areas of the strained semiconductor layer that lie beneath the pattern. Subsequently, a heating step is applied to the semiconductor device to cause a relaxation in areas of the strained layer which do not lie beneath the semiconductor material pattern, whereby dislocations result in the relaxed areas and impair electrical transport therethrough.
Unger, Scott R; Hottle, Troy A; Hobbs, Shakira R; Thiel, Cassandra L; Campion, Nicole; Bilec, Melissa M; Landis, Amy E
2017-01-01
Background While petroleum-based plastics are extensively used in health care, recent developments in biopolymer manufacturing have created new opportunities for increased integration of biopolymers into medical products, devices and services. This study compared the environmental impacts of single-use disposable devices with increased biopolymer content versus typically manufactured devices in hysterectomy. Methods A comparative life cycle assessment of single-use disposable medical products containing plastic(s) versus the same single-use medical devices with biopolymers substituted for plastic(s) at Magee-Women's Hospital (Magee) in Pittsburgh, PA and the products used in four types of hysterectomies that contained plastics potentially suitable for biopolymer substitution. Magee is a 360-bed teaching hospital, which performs approximately 1400 hysterectomies annually. Results There are life cycle environmental impact tradeoffs when substituting biopolymers for petroplastics in procedures such as hysterectomies. The substitution of biopolymers for petroleum-based plastics increased smog-related impacts by approximately 900% for laparoscopic and robotic hysterectomies, and increased ozone depletion-related impacts by approximately 125% for laparoscopic and robotic hysterectomies. Conversely, biopolymers reduced life cycle human health impacts, acidification and cumulative energy demand for the four hysterectomy procedures. The integration of biopolymers into medical products is correlated with reductions in carcinogenic impacts, non-carcinogenic impacts and respiratory effects. However, the significant agricultural inputs associated with manufacturing biopolymers exacerbate environmental impacts of products and devices made using biopolymers. Conclusions The integration of biopolymers into medical products is correlated with reductions in carcinogenic impacts, non-carcinogenic impacts and respiratory effects; however, the significant agricultural inputs associated with manufacturing biopolymers exacerbate environmental impacts.
Schmalz, Gottfried; Galler, Kerstin M
2017-04-01
Biocompatibility of dental materials has gained increasing interest during recent decades. Meanwhile, legal regulations and standard test procedures are available to evaluate biocompatibility. Herein, these developments will be exemplarily outlined and some considerations for the development of novel materials will be provided. Different aspects including test selection, release of substances, barriers, tissue healing, antibacterial substances, nanoparticles and environmental aspects will be covered. The provided information is mainly based on a review of the relevant literature in international peer reviewed journals, on regulatory documents and on ISO standards. Today, a structured and systematic approach for demonstrating biocompatibility from both a scientific and regulatory point of view is based on a clinical risk assessment in an early stage of material development. This includes the analysis of eluted substances and relevant barriers like dentin or epithelium. ISO standards 14971, 10993, and 7405 specify the modes for clinical risk assessment, test selection and test performance. In contact with breached tissues, materials must not impair the healing process. Antibacterial effects should be based on timely controllable substances or on repellant surfaces. Nanoparticles are produced by intraoral grinding irrespective of the content of nanoparticles in the material, but apparently at low concentrations. Concerns regarding environmental aspects of mercury from amalgam can be met by amalgam separating devices. The status for other materials (e.g. bisphenol-A in resin composites) needs to be evaluated. Finally, the public interest for biocompatibility issues calls for a suitable strategy of risk communication. A wise use of the new tools, especially the clinical risk assessment should aim at preventing the patients, professionals and the environment from harm but should not block the development of novel materials. However, biocompatibility must always be weighed against the beneficial effects of materials in curing/preventing oral diseases. Copyright © 2017. Published by Elsevier Ltd.
Phosphorylation of fibrous materials as a "green" method of their functional diversification =
NASA Astrophysics Data System (ADS)
Volkov, Vadim
The need for the material diversification is typically demanded in research and industry, and it stems from the particular applications of the given material. The current work describes three successful applications of in vitro enzymatic modification of fibrous materials. The chosen materials are silk fibroin (SF) from Bombyx mori (domesticated silkworm) and human hair keratin; the modification is phosphorylation with an ATP as a source of exogenous phosphate group. Protein kinase A from bovine source was the enzyme of choice. Natural fibrous materials are known for their outstanding mechanical properties, environmental stability, biocompatibility and shape control. In the last decades, the knowledge on both SF and keratin has considerably increased, regarding their fine structure and molecular biology, similarly to their practical applications in the field of biotechnology. Produced through sustainable, relatively simple and cheap processes, the natural fibrous materials are one of the main raw sources for biomaterial production. Unlike many biologically derived proteins, both silk and keratin are inherently stable to environmental changes and are mechanically robust. Silk and keratin contain several functional groups on the backbone and side chains of their constituting proteins, therefore exerting an ideal components for production of different protein-derived biomaterials. Therefore, it was of our interest to explore the possibility of "green" treatment of SF and keratin for biomedical (SF) and cosmetic (keratin) applications. The piece of evidence, presented in this thesis, strongly support the idea of enzymatically-mediated in vitro modification of both materials. Although high enzymatic specificity, accompanied by steric hindrance, resulted in somewhat low levels of phosphorylation, it was sufficient to cause considerable structural (SF) and chemical (SF and keratin) changes. The obtained results indicate that kinases can be potentially used to diversify both fibrous material types for a wide range of applications. This is particularly important in the fields of biocompatible devices, or any implementations, designed towards a contact with living tissue. None
Pietrzyńska, Monika; Czerwiński, Michał; Voelkel, Adam
2017-07-15
Polymer-ceramic materials based on poly(vinyl alcohol) (PVA) and hydroxyapatite were applied as sorption material in Monolithic In-Needle Extraction (MINE) device. The presented device provides new possibilities for the examination of bisphosphonates affinity for bone and will be a helpful tool in evaluation of potential antiresorptive drugs suitability. A ceramic part of monoliths was prepared by incorporation of hydroxyapatite (HA) into the reaction mixture or by using a soaking method (mineralization of HA on the PVA). The parameters of synthesis conditions were optimized to achieve a monolithic material having the appropriate dimensions after the soaking process enabling placing of the monolithic material inside the needle. Furthermore, the material must have had optimal dimensions after the re-soaking process to fit perfectly to the needle. Among the sixteen monolithic materials, eight of them were selected for further study, and then four of them were selected as a sorbent material for the MINE device. The material properties were examined on the basis of several parameters: swelling ratio, initial mass reversion and initial diameter reversion, mass growth due to the HA formation, and antiresorptive drug sorption. The MINE device might be then used as a tool for examination of interactions between bisphosphonate and bone. The simulated body fluid containing sodium risedronate (RSD) as a standard compound was passed through the MINE device. The obtained device allowed for sorption about 0.38mg of RSD. The desorption process was carried out in five steps allowing insightful analysis. The MINE device turned out to be a helpful tool for determination of the bisphosphonates affinity to the ceramic part of sorbent (hydroxyapatite) and to assess the usefulness of them as antiresorptive drugs in the future. Copyright © 2017 Elsevier B.V. All rights reserved.
DOE Office of Scientific and Technical Information (OSTI.GOV)
Bauer, Stephen J.; Glover, Steven F.; Pfeifle, Tom
A device for electrofracturing a material sample and analyzing the material sample is disclosed. The device simulates an in situ electrofracturing environment so as to obtain electrofractured material characteristics representative of field applications while allowing permeability testing of the fractured sample under in situ conditions.
Hydrogen generation systems utilizing sodium silicide and sodium silica gel materials
DOE Office of Scientific and Technical Information (OSTI.GOV)
Wallace, Andrew P.; Melack, John M.; Lefenfeld, Michael
Systems, devices, and methods combine reactant materials and aqueous solutions to generate hydrogen. The reactant materials can sodium silicide or sodium silica gel. The hydrogen generation devices are used in fuels cells and other industrial applications. One system combines cooling, pumping, water storage, and other devices to sense and control reactions between reactant materials and aqueous solutions to generate hydrogen. Multiple inlets of varied placement geometries deliver aqueous solution to the reaction. The reactant materials and aqueous solution are churned to control the state of the reaction. The aqueous solution can be recycled and returned to the reaction. One systemmore » operates over a range of temperatures and pressures and includes a hydrogen separator, a heat removal mechanism, and state of reaction control devices. The systems, devices, and methods of generating hydrogen provide thermally stable solids, near-instant reaction with the aqueous solutions, and a non-toxic liquid by-product.« less
Welch, James D.
2000-01-01
Disclosed are semiconductor systems, such as integrated circuits utilizing Schotky barrier and/or diffused junction technology, which semiconductor systems incorporate material(s) that form rectifying junctions in both metallurgically and/or field induced N and P-type doping regions, and methods of their use. Disclosed are Schottky barrier based inverting and non-inverting gate voltage channel induced semiconductor single devices with operating characteristics similar to multiple device CMOS systems and which can be operated as modulators, N and P-channel MOSFETS and CMOS formed therefrom, and (MOS) gate voltage controlled rectification direction and gate voltage controlled switching devices, and use of such material(s) to block parasitic current flow pathways. Simple demonstrative five mask fabrication procedures for inverting and non-inverting gate voltage channel induced semiconductor single devices with operating characteristics similar to multiple device CMOS systems are also presented.
Hydrogen generation systems utilizing sodium silicide and sodium silica gel materials
Wallace, Andrew P.; Melack, John M.; Lefenfeld, Michael
2015-07-14
Systems, devices, and methods combine reactant materials and aqueous solutions to generate hydrogen. The reactant materials can sodium silicide or sodium silica gel. The hydrogen generation devices are used in fuels cells and other industrial applications. One system combines cooling, pumping, water storage, and other devices to sense and control reactions between reactant materials and aqueous solutions to generate hydrogen. Multiple inlets of varied placement geometries deliver aqueous solution to the reaction. The reactant materials and aqueous solution are churned to control the state of the reaction. The aqueous solution can be recycled and returned to the reaction. One system operates over a range of temperatures and pressures and includes a hydrogen separator, a heat removal mechanism, and state of reaction control devices. The systems, devices, and methods of generating hydrogen provide thermally stable solids, near-instant reaction with the aqueous solutions, and a non-toxic liquid by-product.
77 FR 38797 - Massachusetts Marine Sanitation Device Standard-Notice of Determination
Federal Register 2010, 2011, 2012, 2013, 2014
2012-06-29
... Coastal Protection Unit, Five Post Office Square, Suite 100, OEP06-1, Boston, MA 02109-3912. Telephone... ENVIRONMENTAL PROTECTION AGENCY [EPA-R01-OW-2012-0201, FRL-9695-8] Massachusetts Marine Sanitation Device Standard--Notice of Determination AGENCY: Environmental Protection Agency (EPA). ACTION: Notice of...
77 FR 36533 - Massachusetts Marine Sanitation Device Standard-Notice of Determination
Federal Register 2010, 2011, 2012, 2013, 2014
2012-06-19
... Protection, Oceans and Coastal Protection Unit, Five Post Office Square, Suite 100, OEP06-1, Boston, MA 02109... ENVIRONMENTAL PROTECTION AGENCY [EPA-R01-OW-2012-0201, FRL-9688-9] Massachusetts Marine Sanitation Device Standard--Notice of Determination AGENCY: Environmental Protection Agency (EPA). ACTION: Notice of...
Smart material platforms for miniaturized devices: implications in disease models and diagnostics.
Verma, Ritika; Adhikary, Rishi Rajat; Banerjee, Rinti
2016-05-24
Smart materials are responsive to multiple stimuli like light, temperature, pH and redox reactions with specific changes in state. Various functionalities in miniaturised devices can be achieved through the application of "smart materials" that respond to changes in their surroundings. The change in state of the materials in the presence of a stimulus may be used for on demand alteration of flow patterns in devices, acting as microvalves, as scaffolds for cellular aggregation or as modalities for signal amplification. In this review, we discuss the concepts of smart trigger responsive materials and their applications in miniaturized devices both for organ-on-a-chip disease models and for point-of-care diagnostics. The emphasis is on leveraging the smartness of these materials for example, to allow on demand sample actuation, ion dependent spheroid models for cancer or light dependent contractility of muscle films for organ-on-a-chip applications. The review throws light on the current status, scope for technological enhancements, challenges for translation and future prospects of increased incorporation of smart materials as integral parts of miniaturized devices.
Material selection indices for design of surgical instruments with long tubular shafts.
Nelson, Carl A
2013-02-01
In any medical device design process, material selection plays an important role. For devices which sustain mechanical loading, strength and stiffness requirements can be significant drivers of the design. This paper examines the specific case of minimally invasive surgical instruments, including robotic instruments, having long, tubular shafts. Material properties-based selection indices are derived for achieving high performance of these devices in terms of strength and stiffness, and the use of these indices for informing the medical device design problem is illustrated.
Volatile chemical reagent detector
Chen, Liaohai; McBranch, Duncan; Wang, Rong; Whitten, David
2004-08-24
A device for detecting volatile chemical reagents based on fluorescence quenching analysis that is capable of detecting neutral electron acceptor molecules. The device includes a fluorescent material, a contact region, a light source, and an optical detector. The fluorescent material includes at least one polymer-surfactant complex. The polymer-surfactant complex is formed by combining a fluorescent ionic conjugated polymer with an oppositely charged surfactant. The polymer-surfactant complex may be formed in a polar solvent and included in the fluorescent material as a solution. Alternatively, the complex may be included in the fluorescent material as a thin film. The use of a polymer-surfactant complex in the fluorescent material allows the device to detect both neutral and ionic acceptor molecules. The use of a polymer-surfactant complex film allows the device and the fluorescent material to be reusable after exposing the fluorescent material to a vacuum for limited time.
NASA Astrophysics Data System (ADS)
Svimonishvili, Tengiz; Zameroski, Nathan; Gilmore, Mark; Schamiloglu, Edl; Gaudet, John; Yan, Lincan
2004-11-01
Secondary Electron Emission (SEE) results from bombarding materials with electrons, atoms, or ions. The amount of secondary emission depends on factors such as bulk and surface properties of materials, energy of incident particles, and their angle of incidence. Total secondary electron emission yield, defined as the number of secondary electrons ejected per primary electron, is an important material parameter. Materials with high yield find use, for instance, in photomultiplier tubes, whereas materials with low yield, such as graphite, are used for SEE suppression in high-power microwave devices. The lower the SEE yield, the better the performance of high-power microwave devices (for example, gyrotrons). Employing a low-energy electron gun (energy range from 5 eV to 2000 eV), our work aims at characterizing and eventually identifying novel materials (with the lowest possible SEE yield) that will enhance operation and efficiency of high-power microwave devices.
Allemand, Pierre M.; Grimes, Randall F.; Ingle, Andrew R.; Cronin, John P.; Kennedy, Steve R.; Agrawal, Anoop; Boulton, Jonathan M.
2001-01-01
An electrochromic device is disclosed having a selective ion transport layer which separates an electrochemically active material from an electrolyte containing a redox active material. The devices are particularly useful as large area architectural and automotive glazings due to there reduced back reaction.
High energy density redox flow device
Chiang, Yet-Ming; Carter, W. Craig; Ho, Bryan Y; Duduta, Mihai; Limthongkul, Pimpa
2014-05-13
Redox flow devices are described in which at least one of the positive electrode or negative electrode-active materials is a semi-solid or is a condensed ion-storing electroactive material, and in which at least one of the electrode-active materials is transported to and from an assembly at which the electrochemical reaction occurs, producing electrical energy. The electronic conductivity of the semi-solid is increased by the addition of conductive particles to suspensions and/or via the surface modification of the solid in semi-solids (e.g., by coating the solid with a more electron conductive coating material to increase the power of the device). High energy density and high power redox flow devices are disclosed. The redox flow devices described herein can also include one or more inventive design features. In addition, inventive chemistries for use in redox flow devices are also described.
NASA Astrophysics Data System (ADS)
Baur, Cary Allen
In this work, novel approaches to the design of highly piezoelectric and flexible polymer composites were explored. Diverging from past work focused on the addition of piezoelectric particles into polymer matrices, this research explores the ability to increase the piezoelectric performance of a host polymer through the incorporation of charge via polarizable, organic particles. The ability to insert charge into polymers, known as electrets, is well documented but widely considered impractical because of the low lifetime and temperature resistance of the inserted charge. Through the addition of particles that are polarizable, charge can be inserted into a system in a stable manner that results in highly charged materials with long lifetimes. Here, carbon structures, such as Buckminsterfullerenes (C60) and single-walled nanotubes (SWNTs), were composited into poly(vinylidene difluoride) at very low loading levels (0.05-0.25 wt%), resulting in the ability to insert stable charge into the system. We show that these highly charged systems can result in a doubling of the piezoelectric response of the host polymer when optimized. The low amount of nanoparticle filler required to improve these materials allows for the advantageous properties of the polymer matrix such as flexibility and compliance to be preserved, enabling highly piezoelectric and flexible system. This dissertation outlines research efforts towards the design and fabrication of 1) polymer composites with high piezoelectric response, 2) piezoelectric composites with increased operating temperatures, 3) motion control devices that incorporate piezoelectric materials and shape memory polymers, and 4) artificial muscles with piezoelectric polymers. The piezoelectric polymer composites developed in this work have potential to be utilized as highly efficient, flexible energy harvesters that can be used to capture ambient energy from environmental vibrations and motion from the human body. As actuators, these materials may find use as rapid-response muscle replacements in legs, arms, fingers, or toes. As sensors, such devices may provide electrical impulses capable of sensing small vibrations due to structural damage or movements. There is a wide range of applications for flexible piezoelectric materials that will continue to expand as technologies in monitoring, energy harvesting, and motion control continue to develop.
Compliant Electrode and Composite Material for Piezoelectric Wind and Mechanical Energy Conversions
NASA Technical Reports Server (NTRS)
Chen, Bin (Inventor)
2015-01-01
A thin film device for harvesting energy from wind. The thin film device includes one or more layers of a compliant piezoelectric material formed from a composite of a polymer and an inorganic material, such as a ceramic. Electrodes are disposed on a first side and a second side of the piezoelectric material. The electrodes are formed from a compliant material, such as carbon nanotubes or graphene. The thin film device exhibits improved resistance to structural fatigue upon application of large strains and repeated cyclic loadings.
Electrochromic-photovoltaic film for light-sensitive control of optical transmittance
Branz, Howard M.; Crandall, Richard S.; Tracy, C. Edwin
1994-01-01
A variable transmittance optical component includes an electrochromic material and a photovoltaic device-type thin film solar cell deposited in a tandem type, monolithic single coating over the component. A bleed resistor of a predetermined value is connected in series across the electrochromic material and photovoltaic device controlling the activation and deactivation of the electrochromic material. The electrical conductivity between the electrochromic material and the photovoltaic device is enhanced by interposing a transparent electrically conductive layer.
PREFACE: Nanoscale Devices and System Integration Conference (NDSI-2004)
NASA Astrophysics Data System (ADS)
Khizroev, Sakhrat; Litvinov, Dmitri
2004-10-01
The inaugural conference on Nanoscale Devices and System Integration (NDSI-2004) was held in Miami, Florida, 15-19 February, 2004. The focus of the conference was `real-life' devices and systems that have recently emerged as a result of various nanotechnology initiatives in chemistry and chemical engineering, physics, electrical engineering, materials science and engineering, biomedical engineering, computer science, robotics, and environmental science. The conference had a single session all-invited speaker format, with the presenters making the `Who's Who in Nanotechnology' list. Contributed work was showcased at a special poster session. The conference, sponsored by the Institute of Electrical and Electronics Engineers (IEEE) and the US Air Force, and endorsed by Materials Research Society (MRS), drew more than 160 participants from fourteen countries. To strengthen the connection between fundamental research and `real-life' applications, the conference featured a large number of presenters from both academia and industry. Among the participating companies were NEC, IBM, Toshiba, AMD, Samsung, Seagate, and Veeco. Nanotechnology has triggered a new wave of research collaborations between researchers from academia and industry with a broad range of specializations. Such a global approach has resulted in a number of breakthrough accomplishments. One of the main goals of this conference was to identify these accomplishments and put the novel technology initiatives and the emerging research teams on the map. Among the key nanotechnology applications demonstrated at NDSI-2004 were carbon-nanotube-based transistors, quantum computing systems, nanophotonic devices, single-molecule electronic devices and biological magnetic sources. Due to the unprecedented success of the conference, the organizing committee of NDSI has unanimously chosen to turn NDSI into an annual international nanotechnology event. The next NDSI is scheduled for 4-6 April, 2005, in Houston, Texas. Details can be found on the conference web site at http://www.nanointernational.org. This special issue of Nanotechnology features selected papers from NDSI-2004.
Fabrication, characterization, and modeling of a biodegradable battery for transient electronics
NASA Astrophysics Data System (ADS)
Edupuganti, Vineet; Solanki, Raj
2016-12-01
Traditionally, emphasis has been placed on durable, long-lasting electronics. However, electronics that are meant to intentionally degrade over time can actually have significant practical applications. Biodegradable, or transient, electronics would open up opportunities in the field of medical implants, where the need for surgical removal of devices could be eliminated. Environmental sensors and, eventually, consumer electronics would also greatly benefit from this technology. An essential component of transient electronics is the battery, which serves as a biodegradable power source. This work involves the fabrication, characterization, and modeling of a magnesium-based biodegradable battery. Galvanostatic discharge tests show that an anode material of magnesium alloy AZ31 extends battery lifetime by over six times, as compared to pure magnesium. With AZ31, the maximum power and capacity of the fabricated device are 67 μW and 5.2 mAh, respectively, though the anode area is just 0.8 cm2. The development of an equivalent circuit model provided insight into the battery's behavior by extracting fitting parameters from experimental data. The model can accurately simulate device behavior, taking into account its intentional degradation. The size of the device and the power it produces are in accordance with typical levels for low-power transient systems.
Comparison of Six Different Silicones In Vitro for Application as Glaucoma Drainage Device
Windhövel, Claudia; Harder, Lisa; Bach, Jan-Peter; Teske, Michael; Grabow, Niels; Eickner, Thomas; Chichkov, Boris; Nolte, Ingo
2018-01-01
Silicones are widely used in medical applications. In ophthalmology, glaucoma drainage devices are utilized if conservative therapies are not applicable or have failed. Long-term success of these devices is limited by failure to control intraocular pressure due to fibrous encapsulation. Therefore, different medical approved silicones were tested in vitro for cell adhesion, cell proliferation and viability of human Sclera (hSF) and human Tenon fibroblasts (hTF). The silicones were analysed also depending on the sample preparation according to the manufacturer’s instructions. The surface quality was characterized with environmental scanning electron microscope (ESEM) and water contact angle measurements. All silicones showed homogeneous smooth and hydrophobic surfaces. Cell adhesion was significantly reduced on all silicones compared to the negative control. Proliferation index and cell viability were not influenced much. For development of a new glaucoma drainage device, the silicones Silbione LSR 4330 and Silbione LSR 4350, in this study, with low cell counts for hTF and low proliferation indices for hSF, and silicone Silastic MDX4-4210, with low cell counts for hSF and low proliferation indices for hTF, have shown the best results in vitro. Due to the high cell adhesion shown on Silicone LSR 40, 40,026, this material is unsuitable. PMID:29495462
Performative building envelope design correlated to solar radiation and cooling energy consumption
NASA Astrophysics Data System (ADS)
Jacky, Thiodore; Santoni
2017-11-01
Climate change as an ongoing anthropogenic environmental challenge is predominantly caused by an amplification in the amount of greenhouse gases (GHGs), notably carbon dioxide (CO2) in building sector. Global CO2 emissions are emitted from HVAC (Heating, Ventilation, and Air Conditioning) occupation to provide thermal comfort in building. In fact, the amount of energy used for cooling or heating building is implication of building envelope design. Building envelope acts as interface layer of heat transfer between outdoor environment and the interior of a building. It appears as wall, window, roof and external shading device. This paper examines performance of various design strategy on building envelope to limit solar radiation and reduce cooling loads in tropical climate. The design strategies are considering orientation, window to wall ratio, material properties, and external shading device. This research applied simulation method using Autodesk Ecotect to investigate simultaneously between variations of wall and window ratio, shading device composition and the implication to the amount of solar radiation, cooling energy consumption. Comparative analysis on the data will determine logical variation between opening and shading device composition and cooling energy consumption. Optimizing the building envelope design is crucial strategy for reducing CO2 emissions and long-term energy reduction in building sector. Simulation technology as feedback loop will lead to better performative building envelope.
Electronic materials testing in commercial aircraft engines
NASA Astrophysics Data System (ADS)
Brand, Dieter
A device for the electronic testing of materials used in commercial aircraft engines is described. The instrument can be used for ferromagnetic, ferrimagnetic, and nonferromagnetic metallic materials, and it functions either optically or acoustically. The design of the device is described and technical data are given. The device operates under the principle of controlled self-inductivity. Its mode of operation is described.
Ivanov, Ilia N.; Simpson, John T.
2013-06-11
An electronic device comprises a drawn glass tube having opposing ends, a semiconductive material disposed inside of the drawn glass tube, and a first electrode and a second electrode disposed at the opposing ends of the drawn glass tube. A method of making an electrical device comprises disposing a semiconductive material inside of a glass tube, and drawing the glass tube with the semiconductive material disposed therein to form a drawn glass tube. The method of making an electrical device also comprises disposing a first electrode and a second electrode on the opposing ends of the drawn glass tube to form an electric device.
Functionalized hexagonal boron nitride nano-coatings for protection of transparent plastics
NASA Astrophysics Data System (ADS)
Van Tran, Thu; Usta, Aybala; Asmatulu, Ramazan
2016-04-01
Nanocoating is the result of a coating application of nanomaterials to build a consistent network of molecules in a paint to protect the surfaces of various materials and devices. Hexagonal Boron Nitride (h-BN) is in two dimensional form with excellent thermal, mechanical and chemical properties. These BN nanocoatings are also a thermally insulating material for heat management. After adding functionalized h-BNs into paints or other coatings, they will absorb the harmful UV part of sunlight and prevent coating against the environmental degradations. The impacts of the environmental factors on the coatings can be substantially eliminated. In the present study, h-BNs were modified with [2-(2-Aminoethylamino) propyl] trimethoxysilane and uniformly dispersed into the polyurethane coatings with different amounts, such as 0.1, 0.2, 0.4, and 0.8wt% to increase hardness and water resistance, and decrease the UV degradation level of coatings and transparent plastics. The prepared samples were characterized by using Fourier Transform Infrared Spectroscopy (FTIR), UV-Vis Spectroscopy, Scanning Electron Microscope (SEM), Water Contact Angle, and Differential Scanning Calorimeter (DSC). The test results showed that the nanocoatings with functionalized h-BN provided excellent physical and chemical behaviors against the UV and other physical degradations on the substrates.
Inorganic Photovoltaics Materials and Devices: Past, Present, and Future
NASA Technical Reports Server (NTRS)
Hepp, Aloysius F.; Bailey, Sheila G.; Rafaelle, Ryne P.
2005-01-01
This report describes recent aspects of advanced inorganic materials for photovoltaics or solar cell applications. Specific materials examined will be high-efficiency silicon, gallium arsenide and related materials, and thin-film materials, particularly amorphous silicon and (polycrystalline) copper indium selenide. Some of the advanced concepts discussed include multi-junction III-V (and thin-film) devices, utilization of nanotechnology, specifically quantum dots, low-temperature chemical processing, polymer substrates for lightweight and low-cost solar arrays, concentrator cells, and integrated power devices. While many of these technologies will eventually be used for utility and consumer applications, their genesis can be traced back to challenging problems related to power generation for aerospace and defense. Because this overview of inorganic materials is included in a monogram focused on organic photovoltaics, fundamental issues and metrics common to all solar cell devices (and arrays) will be addressed.
Evaluation of Environmental Effects of Wave Energy Convertor Arrays
NASA Astrophysics Data System (ADS)
Jones, C. A.
2015-12-01
Stakeholders and regulators in the U.S. are generally uncertain as to the potential environmental impacts posed by deployments of marine and hydrokinetic (MHK) devices, and in particular wave energy conversion (WEC) devices, in coastal waters. The first pilot-scale WEC deployments in the U.S. have had to absorb unsustainable costs and delays associated with permitting to get devices in the water. As such, there is an urgent industry need to streamline the technical activities and processes used to assess potential environmental impacts. To enable regulators and stakeholders to become more comfortable and confident with developing effective MHK environmental assessments, a better understanding of the potential environmental effects induced by arrays of WEC devices is needed. A key challenge in developing this understanding is that the assessment of the WEC effects must come prior to deployment. A typical approach in similar environmental assessments is to use numerical models to simulate the WEC devices and array layouts so that the appropriate environmental stressors and receptors can be identified and assessed. Sandia National Laboratories (SNL) and the U.S. Department of Energy are fulfilling the industry-wide need to develop "WEC-friendly" open-source numerical modeling tools capable of assessing potential changes to the physical environment caused by the operation of WEC arrays. Studies using these tools will advance the nation's general knowledge of the interrelationships among the number, size, efficiency, and configuration of MHK arrays and the subsequent effects these relationships may have on the deployment environment. By better understanding these relationships, industry, stakeholders, and regulators will be able to work together to optimize WEC deployments such that environmental impacts are minimized while power output is maximized. The present work outlines the initial effort in coupling the SNL WEC-friendly tools with the environmental assessment process. The development of the initial phases of a WEC case study in the offshore waters of Newport, Oregon will be presented. Examples of the quantitative evaluation of changes to important parameters that mau constitute an environmental stressors will be presented.
10 CFR 51.80 - Draft environmental impact statement-materials license.
Code of Federal Regulations, 2013 CFR
2013-01-01
... 10 Energy 2 2013-01-01 2013-01-01 false Draft environmental impact statement-materials license. 51...-Regulations Implementing Section 102(2) Draft Environmental Impact Statements-Materials Licenses § 51.80 Draft environmental impact statement—materials license. (a) The NRC staff will either prepare a draft environmental...
10 CFR 51.80 - Draft environmental impact statement-materials license.
Code of Federal Regulations, 2012 CFR
2012-01-01
... 10 Energy 2 2012-01-01 2012-01-01 false Draft environmental impact statement-materials license. 51...-Regulations Implementing Section 102(2) Draft Environmental Impact Statements-Materials Licenses § 51.80 Draft environmental impact statement—materials license. (a) The NRC staff will either prepare a draft environmental...
10 CFR 51.80 - Draft environmental impact statement-materials license.
Code of Federal Regulations, 2011 CFR
2011-01-01
... 10 Energy 2 2011-01-01 2011-01-01 false Draft environmental impact statement-materials license. 51...-Regulations Implementing Section 102(2) Draft Environmental Impact Statements-Materials Licenses § 51.80 Draft environmental impact statement—materials license. (a) The NRC staff will either prepare a draft environmental...
10 CFR 51.80 - Draft environmental impact statement-materials license.
Code of Federal Regulations, 2014 CFR
2014-01-01
... 10 Energy 2 2014-01-01 2014-01-01 false Draft environmental impact statement-materials license. 51...-Regulations Implementing Section 102(2) Draft Environmental Impact Statements-Materials Licenses § 51.80 Draft environmental impact statement—materials license. (a) The NRC staff will either prepare a draft environmental...
10 CFR 51.80 - Draft environmental impact statement-materials license.
Code of Federal Regulations, 2010 CFR
2010-01-01
... 10 Energy 2 2010-01-01 2010-01-01 false Draft environmental impact statement-materials license. 51...-Regulations Implementing Section 102(2) Draft Environmental Impact Statements-Materials Licenses § 51.80 Draft environmental impact statement—materials license. (a) The NRC staff will either prepare a draft environmental...
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.
Kim, Sung-Kon; Kim, Yun Ki; Lee, Hyunjoo; Lee, Sang Bok; Park, Ho Seok
2014-04-01
Strong demand for high-performance energy-storage devices has currently motivated the development of emerging capacitive materials that can resolve their critical challenge (i.e., low energy density) and that are renewable and inexpensive energy-storage materials from both environmental and economic viewpoints. Herein, the pseudocapacitive behavior of lignin nanocrystals confined on reduced graphene oxides (RGOs) used for renewable energy-storage materials is demonstrated. The excellent capacitive characteristics of the renewable hybrid electrodes were achieved by synergizing the fast and reversible redox charge transfer of surface-confined quinone and the interplay with electron-conducting RGOs. Accordingly, pseudocapacitors with remarkable rate and cyclic performances (~96 % retention after 3000 cycles) showed a maximum capacitance of 432 F g(-1), which was close to the theoretical capacitance of 482 F g(-1) and sixfold higher than that of RGO (93 F g(-1)). The chemical strategy delineated herein paves the way to develop advanced renewable electrodes for energy-storage applications and understand the redox chemistry of electroactive biomaterials. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.
Analysis of an operator-differential model for magnetostrictive energy harvesting
NASA Astrophysics Data System (ADS)
Davino, D.; Krejčí, P.; Pimenov, A.; Rachinskii, D.; Visone, C.
2016-10-01
We present a model of, and analysis of an optimization problem for, a magnetostrictive harvesting device which converts mechanical energy of the repetitive process such as vibrations of the smart material to electrical energy that is then supplied to an electric load. The model combines a lumped differential equation for a simple electronic circuit with an operator model for the complex constitutive law of the magnetostrictive material. The operator based on the formalism of the phenomenological Preisach model describes nonlinear saturation effects and hysteresis losses typical of magnetostrictive materials in a thermodynamically consistent fashion. We prove well-posedness of the full operator-differential system and establish global asymptotic stability of the periodic regime under periodic mechanical forcing that represents mechanical vibrations due to varying environmental conditions. Then we show the existence of an optimal solution for the problem of maximization of the output power with respect to a set of controllable parameters (for the periodically forced system). Analytical results are illustrated with numerical examples of an optimal solution.
Emerging technologies for high performance infrared detectors
NASA Astrophysics Data System (ADS)
Tan, Chee Leong; Mohseni, Hooman
2018-01-01
Infrared photodetectors (IRPDs) have become important devices in various applications such as night vision, military missile tracking, medical imaging, industry defect imaging, environmental sensing, and exoplanet exploration. Mature semiconductor technologies such as mercury cadmium telluride and III-V material-based photodetectors have been dominating the industry. However, in the last few decades, significant funding and research has been focused to improve the performance of IRPDs such as lowering the fabrication cost, simplifying the fabrication processes, increasing the production yield, and increasing the operating temperature by making use of advances in nanofabrication and nanotechnology. We will first review the nanomaterial with suitable electronic and mechanical properties, such as two-dimensional material, graphene, transition metal dichalcogenides, and metal oxides. We compare these with more traditional low-dimensional material such as quantum well, quantum dot, quantum dot in well, semiconductor superlattice, nanowires, nanotube, and colloid quantum dot. We will also review the nanostructures used for enhanced light-matter interaction to boost the IRPD sensitivity. These include nanostructured antireflection coatings, optical antennas, plasmonic, and metamaterials.
Reducing the nucleation barrier in magnetocaloric Heusler alloys by nanoindentation
NASA Astrophysics Data System (ADS)
Niemann, R.; Hahn, S.; Diestel, A.; Backen, A.; Schultz, L.; Nielsch, K.; Wagner, M. F.-X.; Fähler, S.
2016-06-01
Magnetocaloric materials are promising as solid state refrigerants for more efficient and environmentally friendly cooling devices. The highest effects have been observed in materials that exhibit a first-order phase transition. These transformations proceed by nucleation and growth which lead to a hysteresis. Such irreversible processes are undesired since they heat up the material and reduce the efficiency of any cooling application. In this article, we demonstrate an approach to decrease the hysteresis by locally changing the nucleation barrier. We created artificial nucleation sites and analyzed the nucleation and growth processes in their proximity. We use Ni-Mn-Ga, a shape memory alloy that exhibits a martensitic transformation. Epitaxial films serve as a model system, but their high surface-to-volume ratio also allows for a fast heat transfer which is beneficial for a magnetocaloric regenerator geometry. Nanoindentation is used to create a well-defined defect. We quantify the austenite phase fraction in its proximity as a function of temperature which allows us to determine the influence of the defect on the transformation.
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.
Materials, processes, and environmental engineering network
NASA Technical Reports Server (NTRS)
White, Margo M.
1993-01-01
The Materials, Processes, and Environmental Engineering Network (MPEEN) was developed as a central holding facility for materials testing information generated by the Materials and Processes Laboratory. It contains information from other NASA centers and outside agencies, and also includes the NASA Environmental Information System (NEIS) and Failure Analysis Information System (FAIS) data. Environmental replacement materials information is a newly developed focus of MPEEN. This database is the NASA Environmental Information System, NEIS, which is accessible through MPEEN. Environmental concerns are addressed regarding materials identified by the NASA Operational Environment Team, NOET, to be hazardous to the environment. An environmental replacement technology database is contained within NEIS. Environmental concerns about materials are identified by NOET, and control or replacement strategies are formed. This database also contains the usage and performance characteristics of these hazardous materials. In addition to addressing environmental concerns, MPEEN contains one of the largest materials databases in the world. Over 600 users access this network on a daily basis. There is information available on failure analysis, metals and nonmetals testing, materials properties, standard and commercial parts, foreign alloy cross-reference, Long Duration Exposure Facility (LDEF) data, and Materials and Processes Selection List data.
Life Cycle Analysis for the Feasibility of Photovoltaic System Application in Indonesia
NASA Astrophysics Data System (ADS)
Yudha, H. M.; Dewi, T.; Risma, P.; Oktarina, Y.
2018-03-01
Electricity has become the basic need for everyone, from industry to domestic. Today electricity source still depends heavily on fossil fuels that soon will be diminished from the earth in around 50 years. This condition demands us to find the renewable energy to support our everyday life. One of the famous renewable energy sources is from solar, harnessed by energy conversion device named solar cells. Countries like Indonesia are gifted with an abundance of sunlight all the yearlong. The application of solar cells with its photovoltaic (PV) technology harnesses the sunlight and converts it into electricity. Although this technology is emerging very fast, it still has some limitation due to the current PV technology, economic feasibility, and its environmental impacts. Life cycle assessment is the method to analyze and evaluate the sustainability of PV system and its environmental impact. This paper presents literature study of PV system from the cradle to grave, it begins with the material choices (from the first generation and the possibility of the fourth generation), manufacturing process, implementation, and ends it with the after-life effect of PV modules. The result of this study will be the insights look of the PV system application in Indonesia, from the best option of material choice, the best method of application, the energy payback time, and finally the possible after life recycle of PV materials.
Nano-Enabled Approaches to Chemical Imaging in Biosystems
Retterer, Scott T.; Morrell-Falvey, Jennifer L.; Doktycz, Mitchel John
2018-02-28
Understanding and predicting how biosystems function require knowledge about the dynamic physicochemical environments with which they interact and alter by their presence. Yet, identifying specific components, tracking the dynamics of the system, and monitoring local environmental conditions without disrupting biosystem function present significant challenges for analytical measurements. Nanomaterials, by their very size and nature, can act as probes and interfaces to biosystems and offer solutions to some of these challenges. At the nanoscale, material properties emerge that can be exploited for localizing biomolecules and making chemical measurements at cellular and subcellular scales. Here, we review advances in chemical imaging enabledmore » by nanoscale structures, in the use of nanoparticles as chemical and environmental probes, and in the development of micro- and nanoscale fluidic devices to define and manipulate local environments and facilitate chemical measurements of complex biosystems. As a result, integration of these nano-enabled methods will lead to an unprecedented understanding of biosystem function.« less
Conducting Polymers in the Fields of Energy, Environmental Remediation, and Chemical-Chiral Sensors.
Ibanez, Jorge G; Rincón, Marina E; Gutierrez-Granados, Silvia; Chahma, M'hamed; Jaramillo-Quintero, Oscar A; Frontana-Uribe, Bernardo A
2018-05-09
Conducting polymers (CPs), thanks to their unique properties, structures made on-demand, new composite mixtures, and possibility of deposit on a surface by chemical, physical, or electrochemical methodologies, have shown in the last years a renaissance and have been widely used in important fields of chemistry and materials science. Due to the extent of the literature on CPs, this review, after a concise introduction about the interrelationship between electrochemistry and conducting polymers, is focused exclusively on the following applications: energy (energy storage devices and solar cells), use in environmental remediation (anion and cation trapping, electrocatalytic reduction/oxidation of pollutants on CP based electrodes, and adsorption of pollutants) and finally electroanalysis as chemical sensors in solution, gas phase, and chiral molecules. This review is expected to be comprehensive, authoritative, and useful to the chemical community interested in CPs and their applications.
Nano-Enabled Approaches to Chemical Imaging in Biosystems
DOE Office of Scientific and Technical Information (OSTI.GOV)
Retterer, Scott T.; Morrell-Falvey, Jennifer L.; Doktycz, Mitchel John
Understanding and predicting how biosystems function require knowledge about the dynamic physicochemical environments with which they interact and alter by their presence. Yet, identifying specific components, tracking the dynamics of the system, and monitoring local environmental conditions without disrupting biosystem function present significant challenges for analytical measurements. Nanomaterials, by their very size and nature, can act as probes and interfaces to biosystems and offer solutions to some of these challenges. At the nanoscale, material properties emerge that can be exploited for localizing biomolecules and making chemical measurements at cellular and subcellular scales. Here, we review advances in chemical imaging enabledmore » by nanoscale structures, in the use of nanoparticles as chemical and environmental probes, and in the development of micro- and nanoscale fluidic devices to define and manipulate local environments and facilitate chemical measurements of complex biosystems. As a result, integration of these nano-enabled methods will lead to an unprecedented understanding of biosystem function.« less
Highly sensitive nanostructure SnO2 based gas sensor for environmental pollutants
NASA Astrophysics Data System (ADS)
Korgaokar, Sushil; Moradiya, Meet; Prajapati, Om; Thakkar, Pranav; Pala, Jay; Savaliya, Chirag; Parikh, Sachin; Markna, J. H.
2017-05-01
A major quantity of pollutants are produced from industries and vehicles in the form of gas. New approaches are needed to solve well-known environmental pollutants like CO, CO2, NO2, SOx. Therefore detection with effective gas sensors is a vital part of pollution prevention efforts. There is a need to develop fast, rapid, cost-effective, highly sensitive, low power, and non-intrusive rugged sensors that can be easily installed. In the present study, nanostructured SnO2 used as a sensitive material in the devices and synthesized using hydrothermal process. The detailed development of the fabrication of SnO2 nanostructures gas sensor is described, which shows the remarkable change in the sensing properties with varying particle size. Additionally, we have used X-ray diffraction, scanning electron microscopy (SEM) for characterization and carefully examined the relative parameters like response magnitude (sensitivity) and selectivity of SnO2 nano structures with different particle size.
Nuclear Thermal Rocket Element Environmental Simulator (NTREES) Upgrade Activities
NASA Technical Reports Server (NTRS)
Emrich, William J. Jr.; Moran, Robert P.; Pearson, J. Boise
2012-01-01
To support the on-going nuclear thermal propulsion effort, a state-of-the-art non nuclear experimental test setup has been constructed to evaluate the performance characteristics of candidate fuel element materials and geometries in representative environments. The facility to perform this testing is referred to as the Nuclear Thermal Rocket Element Environment Simulator (NTREES). This device can simulate the environmental conditions (minus the radiation) to which nuclear rocket fuel components will be subjected during reactor operation. Test articles mounted in the simulator are inductively heated in such a manner so as to accurately reproduce the temperatures and heat fluxes which would normally occur as a result of nuclear fission and would be exposed to flowing hydrogen. Initial testing of a somewhat prototypical fuel element has been successfully performed in NTREES and the facility has now been shutdown to allow for an extensive reconfiguration of the facility which will result in a significant upgrade in its capabilities
Decontamination systems information and research program. Quarterly report, April--June 1996
DOE Office of Scientific and Technical Information (OSTI.GOV)
NONE
This report contains separate reports on the following subtasks: analysis of the Vortec cyclone melting system for remediation of PCB contaminated soils using CFD; drain enhanced soil flushing using prefabricated vertical drains; performance and characteristics evaluation of acrylates as grout barriers; development of standard test protocol barrier design models for desiccation barriers, and for in-situ formed barriers; in-situ bioremediation of chlorinated solvents at Portsmouth Gaseous Diffusion Plant; development of a decision support system and a prototype database for management of the EM50 technology development program; GIS-based infrastructure for site characterization and remediation; treatment of mixed wastes via fluidized bed steammore » reforming; use of centrifugal membrane technology to treat hazardous/radioactive waste; environmental pollution control devices based on novel forms of carbon; development of instrumental methods for analysis of nuclear wastes and environmental materials; production and testing of biosorbents and cleaning solutions for D and D; use of SpinTek centrifugal membrane and sorbents/cleaning solutions for D and D; West Virginia High Tech Consortium Foundation--Environmental support program; small business interaction opportunities; and approach for assessing potential voluntary environmental protection.« less
Nano-Bio Quantum Technology for Device-Specific Materials
NASA Technical Reports Server (NTRS)
Choi, Sang H.
2009-01-01
The areas discussed are still under development: I. Nano structured materials for TE applications a) SiGe and Be.Te; b) Nano particles and nanoshells. II. Quantum technology for optical devices: a) Quantum apertures; b) Smart optical materials; c) Micro spectrometer. III. Bio-template oriented materials: a) Bionanobattery; b) Bio-fuel cells; c) Energetic materials.
21 CFR 878.3500 - Polytetrafluoroethylene with carbon fibers composite implant material.
Code of Federal Regulations, 2010 CFR
2010-04-01
... composite implant material. 878.3500 Section 878.3500 Food and Drugs FOOD AND DRUG ADMINISTRATION... Prosthetic Devices § 878.3500 Polytetrafluoroethylene with carbon fibers composite implant material. (a) Identification. A polytetrafluoroethylene with carbon fibers composite implant material is a porous device...
2015-01-01
The healthcare sector is a driver of economic growth in the U.S., with spending on healthcare in 2012 reaching $2.8 trillion, or 17% of the U.S. gross domestic product, but it is also a significant source of emissions that adversely impact environmental and public health. The current state of the healthcare industry offers significant opportunities for environmental efficiency improvements, potentially leading to reductions in costs, resource use, and waste without compromising patient care. However, limited research exists that can provide quantitative, sustainable solutions. The operating room is the most resource-intensive area of a hospital, and surgery is therefore an important focal point to understand healthcare-related emissions. Hybrid life cycle assessment (LCA) was used to quantify environmental emissions from four different surgical approaches (abdominal, vaginal, laparoscopic, and robotic) used in the second most common major procedure for women in the U.S., the hysterectomy. Data were collected from 62 cases of hysterectomy. Life cycle assessment results show that major sources of environmental emissions include the production of disposable materials and single-use surgical devices, energy used for heating, ventilation, and air conditioning, and anesthetic gases. By scientifically evaluating emissions, the healthcare industry can strategically optimize its transition to a more sustainable system. PMID:25517602
Oligomer Molecules for Efficient Organic Photovoltaics.
Lin, Yuze; Zhan, Xiaowei
2016-02-16
Solar cells, a renewable, clean energy technology that efficiently converts sunlight into electricity, are a promising long-term solution for energy and environmental problems caused by a mass of production and the use of fossil fuels. Solution-processed organic solar cells (OSCs) have attracted much attention in the past few years because of several advantages, including easy fabrication, low cost, lightweight, and flexibility. Now, OSCs exhibit power conversion efficiencies (PCEs) of over 10%. In the early stage of OSCs, vapor-deposited organic dye materials were first used in bilayer heterojunction devices in the 1980s, and then, solution-processed polymers were introduced in bulk heterojunction (BHJ) devices. Relative to polymers, vapor-deposited small molecules offer potential advantages, such as a defined molecular structure, definite molecular weight, easy purification, mass-scale production, and good batch-to-batch reproducibility. However, the limited solubility and high crystallinity of vapor-deposited small molecules are unfavorable for use in solution-processed BHJ OSCs. Conversely, polymers have good solution-processing and film-forming properties and are easily processed into flexible devices, whereas their polydispersity of molecular weights and difficulty in purification results in batch to batch variation, which may hamper performance reproducibility and commercialization. Oligomer molecules (OMs) are monodisperse big molecules with intermediate molecular weights (generally in the thousands), and their sizes are between those of small molecules (generally with molecular weights <1000) and polymers (generally with molecular weights >10000). OMs not only overcome shortcomings of both vapor-deposited small molecules and solution-processed polymers, but also combine their advantages, such as defined molecular structure, definite molecular weight, easy purification, mass-scale production, good batch-to-batch reproducibility, good solution processability, and film-forming properties. Therefore, OMs are a good choice for solution-processed reproducible OSCs toward scalable commercialized applications. Considerable efforts have been dedicated to developing new OM electron donors and electron acceptors for OSCs. So far, the highest PCEs of solution-processed OSCs based on OM donors and acceptors are 9-10% and 6-7%, respectively. OM materials have become promising alternatives to polymer and/or fullerene materials for efficient and stable OSCs. In this Account, we present a brief survey of the recent developments in solution-processable OM electron donors and acceptors and their application in OSCs. Rational design of OMs with star- and linear-shaped structures based on triphenylamine, benzodithiophene, and indacenodithiophene units and their impacts on device performance are discussed. Structure-property relationships are also proposed. Furthermore, the remaining challenges and the key research directions in the near future are also addressed. In the next years, an interdisciplinary approach involving novel OM materials, especially electron acceptor materials, accurate morphology optimization, and advanced device technologies will probably bring high-efficiency and stable OSCs to final commercialization.
Code of Federal Regulations, 2011 CFR
2011-04-01
... ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES MEDICAL DEVICE REPORTING User... device; (10) Event problem codes—patient code and device code (refer to the “MEDWATCH Medical Device... device was involved, nature of the problem, patient followup or required treatment, and any environmental...
Code of Federal Regulations, 2010 CFR
2010-04-01
... ADMINISTRATION, DEPARTMENT OF HEALTH AND HUMAN SERVICES (CONTINUED) MEDICAL DEVICES MEDICAL DEVICE REPORTING User... device; (10) Event problem codes—patient code and device code (refer to the “MEDWATCH Medical Device... device was involved, nature of the problem, patient followup or required treatment, and any environmental...
NASA Astrophysics Data System (ADS)
Alomairy, Sultan
Organic photovoltaic (OPV) devices have been developed extensively and optimised due to the use of nanomaterials in their construction. More recently, the demand for such devices to be flexible and mechanically robust has been a major area of research. Presently, Indium Tin Oxide (ITO) is the material that is used almost exclusively for transparent electrode. However, it has several drawbacks such as brittleness, high refractive index and high processing temperature. Furthermore, the price of ITO has been highly volatile due to scarcity of indium resources and the increased consumption of the material. Therefore, cheap, flexible and solution-processed transparent conductors are required for emerging optoelectronic devices with flexible construction which can be promising for wearable or environmentally adaptable devices purposes such as flexible solar cells and displays. Therefore, over the past decade an alternative material has been sought intensively, particularly in the need for producing large area flexible transparent electrodes. Many materials have been investigated but most investigations have focused on carbon nanotube (CNT), graphene flakes and metallic nanowires. Silver nanowires (Ag NWs) networks have been proven to show a high electrical conductivity with high optical transmittance. This special characteristic is desirable in transparent conductive electrodes in optoelectronic applications such as solar cells, light emitting diodes, and touch screen. On the other hand, Polymeric substrates that act as a non-brittle scaffold as well as protective packaging of the OPV are an essential element for such an “All-plastic” device. However, for such applications where the coating should be relatively hard a bottleneck to fabricating large area homogeneous films is associated with the formation of cracks as a result of local mismatches in mechanical properties during film formation. In this work, the fabrication and characterization of flexible transparent electrodes of Ag NWs on flexible substrates by spray deposition technique have been described. Furthermore, a way to enhance the electrical and mechanical properties of the Ag NWs transparent electrodes by incorporating a low density ensemble of graphene on top of the metal electrode networks using the Langmuir-Schafer has been achieved. Interestingly, the electrical conductivity in these hybrid electrodes is stable over relatively large strains during mechanical agitation indicating that such electrodes may have important application in future applications. Finally, producing crack-free monolayer latex over large area has been fabricated and characterised. Therefore, the polymer latex thin film has promising applications as purposes of hard coatings.
Kinematic control model for light weighting mechanism of excavator attached to rotary working device
NASA Astrophysics Data System (ADS)
Lee, Choongho; Lee, Sangsik; Cho, Youngtae; Im, Kwanghee
2007-07-01
An excavator attached to a rotary working device is used principally in industrial work. In particular, they are used in the building industry and public works. This research concerns the rotary automatic control of an excavator attached to a rotary working device. The drilling excavator is used in the crushed stone industry and the dragline excavation system is employed in the construction industry. Cases of the excavator's use in agriculture have been the subject of a relatively few studies. However, several modified excavator designs have been released in recent years. Applied excavator products are primarily utilized under relatively severe environmental conditions. In this study, we focus on the uses of an excavator in agricultural work. The readjustment of arable land and the reduction of weeds in agricultural applications both require skilled hand-operation of the machines. As such workers have been shown to develop problems with regard to working posture and proper positioning while laboring, a more appropriate excavator design may prove useful in such applications. Therefore, this pilot study is focused primarily on the rotary automatic control of an excavator attached to a rotary working device, and will adapt smart materials to the excavator applications for developing redesigned excavator having a light weight. The excavator is attached to a rotary working device on a normal excavator's platform, and the position and orientation of the mechanism between the joints and the rotary working device was determined. Simulations were also conducted of the excavator attached to the rotary working device. With an eye toward the use of this mechanism in agricultural work, we also conducted a set of kinematic analyses. The rotary working device was assumed to have 3 DOF, and was comprised of 5 links. Computer simulations were also conducted using the developed excavator model. In order to adequately evaluate the possible performance of such a system, kinetic analysis, simulation with a soil model, FEM analysis with structural strength analysis, and changes to the smart materials with high rigidity will be required in the future. In addition, experiment and analysis of a prototype, durability experiments, and analyses utilizing S-N curves will be necessary, as well further research into the overall reliability of such a product.